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  • 201.
    Günaydın, Gökçe
    et al.
    Division of Clinical Immunology, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, Sweden.
    Nordgren, Johan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine.
    Svensson, Lennart
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine.
    Hammarström, Lennart
    Division of Clinical Immunology, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, Sweden.
    TLR3-dependent antibody response against rotavirus in individuals with immunoglobulin A deficiency2013In: Journal of Infectious Diseases, ISSN 0022-1899, E-ISSN 1537-6613Article in journal (Refereed)
  • 202. Order onlineBuy this publication >>
    Haarhaus, Mathias
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry.
    Bone alkaline phosphatase isoforms in chronic kidney disease: mineral and bone disorder2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Chronic kidney disease (CKD) is associated with increased mortality and cardiovascular complications. Disturbances in mineral metabolism occur early <luring the course of CKD and several components of the CKD-mineral and bone disorder (CKD-MBD) are independent predictors of mortality. Alkaline phosphatase (ALP) is necessary for skeletal mineralization and is also involved in the process of vascular calcification. In recent years, ALP has evolved as a strong predictor of mortality in the CKD population. The significant role of ALP in the mineralization process renders it a putative target for the treatment and prevention of vascular calcification. Three circulating isoforms of bone ALP (BALP) have been identified (B/I, B 1, and B2). A fourth isoform, Blx, has been identified exclusively in serum from patients with CKD. The aim of the present thesis was to further elucidate the role ofthe BALP isoforms in CKD with respect to bone abnormalities and vascular calcification.

    In study I we identified the novel BALP isoform Blx in 20% of patients with mild to moderate CKD. Blx was associated with lower glomerular filtration rate and higher serum phosphate and calcium x phosphate product, which are risk factors for cardiovascular mortality in CKD. We also identified the BALP isoforms B/I, Bl and B2 as predictors of total hip bone mineral density.

    Study II was an experimental study, investigating the role of the BALP isoforms in phosphate induced calcification of human aortic smooth muscle cells (HASMCs). We found that the ALP expressed in HASMCs is exclusively BALP. Phosphate induced calcification of HASMCs was associated with increased BALP isoforms B/I, Blx, and B2 activities, which implies functional differences between the BALP isoforms in HASMC calcification.

    In study III we investigated the association of BALP isoforms in serum and histomorphometric parameters of bone in patients on chronic hemodialysis. W e identified the BALP isoform Blx as a novel marker for reduced osteoblastic activity.

    Study IV was a prospective cohort study of the association of serum BALP isoforms with aortic calcification and vascular stiffness in prevalent chronic dialysis patients. Blx was associated with baseline and time varying vascular stiffness, determined by pulse wave velocity, but not with calcification of the abdominal aorta. We also found an association of Blx with better event-free survival.

    In conclusion, these studies demonstrate that the BALP isoforms, especially isoform Blx, are involved in different aspects of CKD-MBD. This opens up for further research to identify the BALP isoforms as diagnostic markers and possible treatment targets in CKD-MBD.

    List of papers
    1. Clinical significance of bone alkaline phosphatase isoforms, including the novel B1x isoform, in mild to moderate chronic kidney disease
    Open this publication in new window or tab >>Clinical significance of bone alkaline phosphatase isoforms, including the novel B1x isoform, in mild to moderate chronic kidney disease
    2009 (English)In: NEPHROLOGY DIALYSIS TRANSPLANTATION, ISSN 0931-0509, Vol. 24, no 11, p. 3382-3389Article in journal (Refereed) Published
    Abstract [en]

    Background. Mineral bone disorder (MBD) is a common complication of chronic kidney disease (CKD) even during the early stages. Bone alkaline phosphatase (BALP) is a marker of bone fort-nation and plays a pivotal role in the mineralization process. Three BALP isoforms (B/I, B1 and B2) have been identified in healthy individuals and a fourth isoform (B1x) has been discovered in serum from dialysis patients. We investigated these BALP isoforms, type I procollagen intact amino-terminal propeptide (PINP), carboxy-terminal telopeptide of type I collagen (CTX) and tartrate-resistant acid phosphatase isoform 5b (TRACP5b), as well as bone mineral density (BMD) in predialysis CKD patients. Methods. PINP, CTX, TRACP5b and BALP isoforms were analysed in serum from 46 patients within CKD stages 3-5. BMD was determined by dual-energy x-ray absorptiometry. Results. PINP, TRACP5b and the BALP isoforms, B/I, B1 and B2, were independent predictors of total hip BMD in all patients. Furthermore, B/I predicted osteopaenia in the hip and in the distal 1/3 of the radius in CKD stage 3. The B1x isoform was detected in nine patients (20%), who had lower GFR, higher phosphate and calcium x phosphate product. Conclusion. We found an association of BALP isoforms and other markers of bone turnover with total hip BMD, which predominantly comprises trabecular bone. The association of the new BALP isoform B1x with risk factors for vascular calcification leads us to hypothesize a possible role for B1x in this process. The significance of the BALP isoforms in CKD remains to be further explored in experimental and clinical settings in conjunction with bone histomorphometry.

    Keywords
    alkaline phosphatase, bone mineral density, bone turnover, mineral bone disorder, predialysis
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-52373 (URN)10.1093/ndt/gfp300 (DOI)
    Available from: 2009-12-18 Created: 2009-12-18 Last updated: 2014-11-06
    2. Calcifying Human Aortic Smooth Muscle Cells Express Different Bone Alkaline Phosphatase Isoforms, Including the Novel B1x Isoform
    Open this publication in new window or tab >>Calcifying Human Aortic Smooth Muscle Cells Express Different Bone Alkaline Phosphatase Isoforms, Including the Novel B1x Isoform
    2013 (English)In: Journal of Vascular Research, ISSN 1018-1172, E-ISSN 1423-0135, Vol. 50, no 2, p. 167-174Article in journal (Refereed) Published
    Abstract [en]

    Background: Vascular calcification, causing cardiovascular morbidity and mortality, is associated with hyperphosphatemia in chronic kidney disease (CKD). In vitro, phosphate induces transdifferentiation of vascular smooth muscle cells to osteoblast-like cells that express alkaline phosphatase (ALP). In vivo, raised serum ALP activities are associated with increased mortality. A new bone ALP isoform (B1x) has been identified in serum from CKD patients. The present study investigated the different ALP isoforms in calcifying human aortic smooth muscle cells (HAoSMCs). Methods: HAoSMCs were cultured for 30 days in medium containing 5 or 10 mmol/l beta-glycerophosphate in the presence or absence of the ALP-specific inhibitor tetramisole. Results: All known bone-specific ALP (BALP) isoforms (B/I, B1x, B1 and B2) were identified in HAoSMCs. beta-Glycerophosphate stimulated calcification of HAoSMCs, which was associated with increased BALP isoforms B/I, B1x and B2. Tetramisole inhibited the beta-glycerophosphate-induced HAoSMC calcification, which was paralleled by the inhibition of the B1x and B/I, but not the other isoforms. Conclusions: HAoSMCs express the four known BALP isoforms. B/I, B1x and B2 could be essential for soft tissue calcification. B/I and B1x were more affected by tetramisole than the other isoforms, which suggests different biological functions during calcification of HAoSMCs.

    Place, publisher, year, edition, pages
    S. Karger, 2013
    Keywords
    Bone-specific alkaline phosphatase, Chronic kidney disease, Human aortic smooth muscle cells, Isoforms, Phosphate, Vascular calcification
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-90089 (URN)10.1159/000346161 (DOI)000314995500008 ()
    Note

    Funding Agencies|Ingrid Asps Foundation for Nephrology Research at Linkoping University||County Council of Ostergotland||Swedish Association for Kidney Patients||

    Available from: 2013-03-21 Created: 2013-03-19 Last updated: 2017-12-06
    3. Bone alkaline phosphatase isoforms in CKD patients on hemodialysis with low and high bone turnover
    Open this publication in new window or tab >>Bone alkaline phosphatase isoforms in CKD patients on hemodialysis with low and high bone turnover
    2014 (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Background: Renal osteodystrophy encompasses the bone histologic abnormalities seen in patients with chronic kidney disease (CKD). The bone-specific alkaline phosphatase (BALP) isoform B1x is exclusively found in serum of some CKD patients.

    Study Design: The aim of this cross-sectional diagnostic test study was to examine the relationship between serum BALP isoform activities and histomorphometric parameters of bone in patients with CKD on chronic hemodialysis.

    Setting & Participants: Anterior iliac crest bone biopsy samples from 40 CKD patients were selected on the basis of bone turnover for histomorphometric analysis. There were samples from 20 patients with low and 20 with non-low bone turnover.

    Index Test: In serum, BALP, BALP isoforms (B/I, B1x, B1 and B2), and parathyroid hormone (PTH) were measured.

    Reference Test or Outcome: Indices of osteoblastic activity and number.

    Other Measurements: Parathyroid hormone

    Results: B1x was found in 21 patients (53%) who had lower median levels of BALP, 18.6 versus 46.9 U/L; B/I, 0.10 versus 0.22 μkat/L; B1, 0.40 versus 0.88 μkat/L; B2, 1.21 versus 2.66 μkat/L; and PTH, 49 versus 287 pg/mL, compared to patients without B1x (p<0.001). B1x correlated inversely with osteoblast number and activity. ROC curves showed that B1x (AUC 0.83) can be used for diagnosis of low osteoblastic activity, while BALP (AUC 0.78) and PTH (AUC 0.77) are useful for diagnosis of high osteoblast number seen with high bone turnover.

    Limitations: Small number of study participants.

    Conclusions: The presence of B1x in serum may be a sign of perturbed osteoblast activity and it may be useful as a diagnostic parameter for low bone turnover rate.

    Keywords
    Bone-specific alkaline phosphatase; isoforms; renal osteodystrophy; osteoblast activity; low bone turnover
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-111868 (URN)
    Available from: 2014-11-06 Created: 2014-11-06 Last updated: 2015-03-31Bibliographically approved
    4. A multicenter prospective study of bone alkaline phosphatase isoforms and arterial calcification in chronic kidney disease patients on dialysis
    Open this publication in new window or tab >>A multicenter prospective study of bone alkaline phosphatase isoforms and arterial calcification in chronic kidney disease patients on dialysis
    2014 (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Chronic kidney disease – mineral and bone disorder (CKD-MBD) is associated with high morbidity and mortality due to frequent cardiovascular (CV) complications. Accelerated arterial stiffening and calcification are associated with serum alkaline phosphatase (ALP) in advanced CKD. We have previously described three bone ALP (BALP) isoforms in healthy individuals and detected a novel isoform, B1x, exclusively in serum from some CKD patients, in bone and in calcifying vascular smooth muscle cells. We investigated the association of these BALP isoforms, abdominal aortic calcification (AAC) score and carotid – femoral pulse wave velocity (PWV), with outcome in a 2-year prospective multicenter study of 68 prevalent dialysis patients participating in the Calcification Outcome in Renal Disease (CORD) study. Twenty-one patients experienced a combined event of all-cause mortality or a first nonfatal CV event during follow-up. PWV (hazard ratio 1.067, P = 0.03) was independently associated with the combined event. B1x was detected in 53 patients and was associated with baseline PWV (Kendall's tau 0.23, P = 0.007) and with variation of PWV over time (estimate 14.14, P = 0.03). Patients with B1x had lower levels of PTH and total ALP, indicating a possible association with low bone turnover. We found no association of BALP isoforms with AAC score. Cox regression revealed B1x as a positive predictor of event free survival (hazard ratio 0.98, P = 0.01). In conclusion, B1x is associated with vascular stiffness in CKD 5D. This finding is contrasted by the ability of B1x to predict longer event free survival in the current study.

    Keywords
    Chronic kidney disease – mineral and bone disorder, dialysis, bone alkaline phosphatase, mortality, cardiovascular disease
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-111869 (URN)
    Available from: 2014-11-06 Created: 2014-11-06 Last updated: 2015-03-31Bibliographically approved
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  • 203.
    Haarhaus, Mathias
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry. Karolinska Institute, Sweden.
    Brandenburg, Vincent
    RWTH University Hospital Aachen, Germany.
    Kalantar-Zadeh, Kamyar
    University of Calif Irvine, CA 92868 USA; University of Calif Los Angeles, CA 90502 USA.
    Stenvinkel, Peter
    Karolinska Institute, Sweden.
    Magnusson, Per
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Alkaline phosphatase: a novel treatment target for cardiovascular disease in CKD2017In: Nature Reviews Nephrology, ISSN 1759-5061, E-ISSN 1759-507X, Vol. 13, no 7, p. 429-442Article, review/survey (Refereed)
    Abstract [en]

    Cardiovascular disease is the main cause of early death in the settings of chronic kidney disease (CKD), type 2 diabetes mellitus (T2DM), and ageing. Cardiovascular events can be caused by an imbalance between promoters and inhibitors of mineralization, which leads to vascular calcification. This process is akin to skeletal mineralization, which is carefully regulated and in which isozymes of alkaline phosphatase (ALP) have a crucial role. Four genes encode ALP isozymes in humans. Intestinal, placental and germ cell ALPs are tissue-specific, whereas the tissue-nonspecific isozyme of ALP (TNALP) is present in several tissues, including bone, liver and kidney. TNALP has a pivotal role in bone calcification. Experimental overexpression of TNALP in the vasculature is sufficient to induce vascular calcification, cardiac hypertrophy and premature death, mimicking the cardiovascular phenotype often found in CKD and T2DM. Intestinal ALP contributes to the gut mucosal defence and intestinal and liver ALPs might contribute to the acute inflammatory response to endogenous or pathogenic stimuli. Here we review novel mechanisms that link ALP to vascular calcification, inflammation, and endothelial dysfunction in kidney and cardiovascular diseases. We also discuss new drugs that target ALP, which have the potential to improve cardiovascular outcomes without inhibiting skeletal mineralization.

  • 204.
    Haarhaus, Mathias
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Nephrology. Department of Nephrology, Karolinska University Hospital, Stockholm, Sweden.
    Fernström, Anders
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Nephrology. Division of Nephrology, Bone and Mineral Metabolism, University of Kentucky, Albert B. Chandler Medical Center, USA.
    Magnusson, Per
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry. Division of Nephrology, Bone and Mineral Metabolism, University of Kentucky, Albert B. Chandler Medical Center, USA.
    A multicenter prospective study of bone alkaline phosphatase isoforms and arterial calcification in chronic kidney disease patients on dialysis2014Manuscript (preprint) (Other academic)
    Abstract [en]

    Chronic kidney disease – mineral and bone disorder (CKD-MBD) is associated with high morbidity and mortality due to frequent cardiovascular (CV) complications. Accelerated arterial stiffening and calcification are associated with serum alkaline phosphatase (ALP) in advanced CKD. We have previously described three bone ALP (BALP) isoforms in healthy individuals and detected a novel isoform, B1x, exclusively in serum from some CKD patients, in bone and in calcifying vascular smooth muscle cells. We investigated the association of these BALP isoforms, abdominal aortic calcification (AAC) score and carotid – femoral pulse wave velocity (PWV), with outcome in a 2-year prospective multicenter study of 68 prevalent dialysis patients participating in the Calcification Outcome in Renal Disease (CORD) study. Twenty-one patients experienced a combined event of all-cause mortality or a first nonfatal CV event during follow-up. PWV (hazard ratio 1.067, P = 0.03) was independently associated with the combined event. B1x was detected in 53 patients and was associated with baseline PWV (Kendall's tau 0.23, P = 0.007) and with variation of PWV over time (estimate 14.14, P = 0.03). Patients with B1x had lower levels of PTH and total ALP, indicating a possible association with low bone turnover. We found no association of BALP isoforms with AAC score. Cox regression revealed B1x as a positive predictor of event free survival (hazard ratio 0.98, P = 0.01). In conclusion, B1x is associated with vascular stiffness in CKD 5D. This finding is contrasted by the ability of B1x to predict longer event free survival in the current study.

  • 205.
    Haarhaus, Mathias
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Nephrology. Department of Nephrology, Karolinska University Hospital, Stockholm, Sweden.
    Monier-Faugere, Marie-Claude
    Division of Nephrology, Bone and Mineral Metabolism, University of Kentucky, Albert B. Chandler Medical Center, USA.
    Magnusson, Per
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry. Division of Nephrology, Bone and Mineral Metabolism, University of Kentucky, Albert B. Chandler Medical Center, USA.
    Malluche, Hartmut H.
    Bone alkaline phosphatase isoforms in CKD patients on hemodialysis with low and high bone turnover2014Manuscript (preprint) (Other academic)
    Abstract [en]

    Background: Renal osteodystrophy encompasses the bone histologic abnormalities seen in patients with chronic kidney disease (CKD). The bone-specific alkaline phosphatase (BALP) isoform B1x is exclusively found in serum of some CKD patients.

    Study Design: The aim of this cross-sectional diagnostic test study was to examine the relationship between serum BALP isoform activities and histomorphometric parameters of bone in patients with CKD on chronic hemodialysis.

    Setting & Participants: Anterior iliac crest bone biopsy samples from 40 CKD patients were selected on the basis of bone turnover for histomorphometric analysis. There were samples from 20 patients with low and 20 with non-low bone turnover.

    Index Test: In serum, BALP, BALP isoforms (B/I, B1x, B1 and B2), and parathyroid hormone (PTH) were measured.

    Reference Test or Outcome: Indices of osteoblastic activity and number.

    Other Measurements: Parathyroid hormone

    Results: B1x was found in 21 patients (53%) who had lower median levels of BALP, 18.6 versus 46.9 U/L; B/I, 0.10 versus 0.22 μkat/L; B1, 0.40 versus 0.88 μkat/L; B2, 1.21 versus 2.66 μkat/L; and PTH, 49 versus 287 pg/mL, compared to patients without B1x (p<0.001). B1x correlated inversely with osteoblast number and activity. ROC curves showed that B1x (AUC 0.83) can be used for diagnosis of low osteoblastic activity, while BALP (AUC 0.78) and PTH (AUC 0.77) are useful for diagnosis of high osteoblast number seen with high bone turnover.

    Limitations: Small number of study participants.

    Conclusions: The presence of B1x in serum may be a sign of perturbed osteoblast activity and it may be useful as a diagnostic parameter for low bone turnover rate.

  • 206.
    Haarhaus, Mathias
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Nephrology. Karolinska University Hospital, Sweden.
    Monier-Faugere, Marie-Claude
    University of Kentucky, KY 40536 USA.
    Magnusson, Per
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Malluche, Hartmut H.
    University of Kentucky, KY 40536 USA.
    Bone Alkaline Phosphatase Isoforms in Hemodialysis Patients With Low Versus Non-Low Bone Turnover: A Diagnostic Test Study2015In: American Journal of Kidney Diseases, ISSN 0272-6386, E-ISSN 1523-6838, Vol. 66, no 1, p. 99-105Article in journal (Refereed)
    Abstract [en]

    Background: Renal osteodystrophy encompasses the bone histologic abnormalities seen in patients with chronic kidney disease (CKD). The bone-specific alkaline phosphatase (bALP) isoform B1x is exclusively found in serum of some patients with CKD. Study Design: The aim of this cross-sectional diagnostic test study was to examine the relationship between serum bALP isoform activity and histomorphometric parameters of bone in patients with CKD receiving maintenance hemodialysis. Settings and Participants: Anterior iliac crest bone biopsy samples from 40 patients with CKD were selected on the basis of bone turnover for histomorphometric analysis. There were samples from 20 patients with low and 20 with non-low bone turnover. Index Test: In serum, bALP, bALP isoforms (B/I, B1x, B1, and B2), and parathyroid hormone (PTH) were measured. Reference Test: Low bone turnover was defined by mineral apposition rate, 0.36 mu m/d. Non-low bone turnover was defined by mineral apposition rate greater than= 0.36 mu m/d. Other Measurements: PTH. Results: B1x was found in 21 patients (53%) who had lower median levels of bALP, 18.6 versus 46.9 U/L; B/I, 0.10 versus 0.22 mu kat/L; B1, 0.40 versus 0.88 mu kat/L; B2, 1.21 versus 2.66 mu kat/L; and PTH, 49 versus 287 pg/mL, compared with patients without B1x (P less than 0.001). 13 patients (65%) with low bone turnover and 8 patients (40%) with non-low bone turnover (P less than 0.2) had detectable B1x. B1x correlated inversely with histomorphometric parameters of bone turnover. Receiver operating characteristic curves showed that B1x can be used for the diagnosis of low bone turnover (area under the curve [AUC], 0.83), whereas bALP (AUC, 0.89) and PTH (AUC, 0.85) are useful for the diagnosis of non-low bone turnover. Limitations: Small number of study participants. Requirement of high-performance liquid chromatography methods for measurement of B1x. Conclusions: B1x, PTH, and bALP have similar diagnostic accuracy in distinguishing low from non-low bone turnover. The presence of B1x is diagnostic of low bone turnover, whereas elevated bALP and PTH levels are useful for the diagnosis of non-low bone turnover.

  • 207. Order onlineBuy this publication >>
    Hagbom, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Rotavirus Disease Mechanisms Diarrhea, Vomiting and Inflammation: How and Why2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Rotavirus infections cause diarrhea and vomiting that can lead to severe dehydration. Despite extensive tissue damage and cell death, the inflammatory response is very limited. The focus of this thesis was to study pathophysiological mechanisms behind diarrhea and vomiting during rotavirus infection and also to investigate the mechanism behind the limited inflammatory response.

    An important discovery in this thesis was that rotavirus infection and the rotavirus toxin NSP4 stimulate release of the neurotransmitter serotonin from intestinal sensory enterochromaffin cells, in vitro and ex vivo. Interestingly, serotonin is known to be a mediator of both diarrhea and vomiting. Moreover, mice pups infected with rotavirus responded with central nervous system (CNS) activation in brain structures associated with vomiting, thus indicating a cross-talk between the gut and brain in rotavirus disease.

    Our finding that rotavirus infection activates the CNS led us to address the hypothesis that rotavirus infection not only activates the vagus nerve to stimulate vomiting, but also suppresses the inflammatory response via the cholinergic anti-inflammatory pathway, both of which are mediated by activated vagal afferent nerve signals into the brain stem. We found that mice lacking an intact vagus nerve, and mice lacking the α7 nicotine acetylcholine receptor (nAChR), being involved in cytokine suppression from macrophages, responded with a higher inflammatory response.

    Moreover, stimulated cytokine release from macrophages, by the rotavirus toxin NSP4, could be attenuated by nicotine, an agonist of the α7 nAChR. Thus, it seems most reasonable that the cholinergic anti-inflammatory pathway contributes to the limited inflammatory response during rotavirus infection. Moreover, rotavirus-infected mice displayed increased intestinal motility at the onset of diarrhea, which was not associated with increased intestinal permeability. The increased motility and diarrhea in infant mice could be attenuated by drugs acting on the enteric nervous system, indicating the importance and contribution of nerves in the rotavirus mediated disease.

    In conclusion, this thesis provides further insight into the pathophysiology of diarrhea and describe for the first time how rotavirus and host cross-talk to induce the vomiting reflex and limit inflammation. Results from these studies strongly support our hypothesis that serotonin and activation of the enteric nervous system and CNS contributes to diarrhea, vomiting and suppression of the inflammatory response in rotavirus disease.

    List of papers
    1. Rotavirus Stimulates Release of Serotonin (5-HT) from Human Enterochromaffin Cells and Activates Brain Structures Involved in Nausea and Vomiting
    Open this publication in new window or tab >>Rotavirus Stimulates Release of Serotonin (5-HT) from Human Enterochromaffin Cells and Activates Brain Structures Involved in Nausea and Vomiting
    Show others...
    2011 (English)In: PLOS PATHOGENS, ISSN 1553-7366, Vol. 7, no 7Article in journal (Refereed) Published
    Abstract [en]

    otavirus (RV) is the major cause of severe gastroenteritis in young children. A virus-encoded enterotoxin, NSP4 is proposed to play a major role in causing RV diarrhoea but how RV can induce emesis, a hallmark of the illness, remains unresolved. In this study we have addressed the hypothesis that RV-induced secretion of serotonin (5-hydroxytryptamine, 5-HT) by enterochromaffin (EC) cells plays a key role in the emetic reflex during RV infection resulting in activation of vagal afferent nerves connected to nucleus of the solitary tract (NTS) and area postrema in the brain stem, structures associated with nausea and vomiting. Our experiments revealed that RV can infect and replicate in human EC tumor cells ex vivo and in vitro and are localized to both EC cells and infected enterocytes in the close vicinity of EC cells in the jejunum of infected mice. Purified NSP4, but not purified virus particles, evoked release of 5-HT within 60 minutes and increased the intracellular Ca(2+) concentration in a human midgut carcinoid EC cell line (GOT1) and ex vivo in human primary carcinoid EC cells concomitant with the release of 5-HT. Furthermore, NSP4 stimulated a modest production of inositol 1,4,5-triphosphate (IP(3)), but not of cAMP. RV infection in mice induced Fos expression in the NTS, as seen in animals which vomit after administration of chemotherapeutic drugs. The demonstration that RV can stimulate EC cells leads us to propose that RV disease includes participation of 5-HT, EC cells, the enteric nervous system and activation of vagal afferent nerves to brain structures associated with nausea and vomiting. This hypothesis is supported by treating vomiting in children with acute gastroenteritis with 5-HT(3) receptor antagonists.

    Place, publisher, year, edition, pages
    Public Library of Science (PLoS), 2011
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-69989 (URN)10.1371/journal.ppat.1002115 (DOI)000293339300012 ()
    Note
    Original Publication: Marie Hagbom, Claudia Istrate, David Engblom, Thommie Karlsson, Jesus Rodriguez-Diaz, Javier Buesa, John A Taylor, Vesa Loitto, Karl-Eric Magnusson, Hakan Ahlman, Ove Lundgren and Lennart Svensson, Rotavirus Stimulates Release of Serotonin (5-HT) from Human Enterochromaffin Cells and Activates Brain Structures Involved in Nausea and Vomiting, 2011, PLOS PATHOGENS, (7), 7, . http://dx.doi.org/10.1371/journal.ppat.1002115 Licensee: Public Library of Science (PLoS) http://www.plos.org/Available from: 2011-08-12 Created: 2011-08-12 Last updated: 2015-05-13
    2. Rotavirus Infection Increases Intestinal Motility but Not Permeability at the Onset of Diarrhea
    Open this publication in new window or tab >>Rotavirus Infection Increases Intestinal Motility but Not Permeability at the Onset of Diarrhea
    Show others...
    2014 (English)In: Journal of Virology, ISSN 0022-538X, E-ISSN 1098-5514, Vol. 88, no 6, p. 3161-3169Article in journal (Refereed) Published
    Abstract [en]

    The disease mechanisms associated with onset and secondary effects of rotavirus (RV) diarrhea remain to be determined and may not be identical. In this study, we investigated whether onset of RV diarrhea is associated with increased intestinal permeability and/or motility. To study the transit time, fluorescent fluorescein isothiocyanate (FITC)-dextran was given to RV-infected adult and infant mice. Intestinal motility was also studied with an opioid receptor agonist (loperamide) and a muscarinic receptor antagonist (atropine). To investigate whether RV increases permeability at the onset of diarrhea, fluorescent 4- and 10-kDa dextran doses were given to infected and noninfected mice, and fluorescence intensity was measured subsequently in serum. RV increased transit time in infant mice. Increased motility was detected at 24 h postinfection (h p.i.) and persisted up to 72 h p.i in pups. Both loperamide and atropine decreased intestinal motility and attenuated diarrhea. Analysis of passage of fluorescent dextran from the intestine into serum indicated unaffected intestinal permeability at the onset of diarrhea (24 to 48 h p.i.). We show that RV-induced diarrhea is associated with increased intestinal motility via an activation of the myenteric nerve plexus, which in turn stimulates muscarinic receptors on intestinal smooth muscles.

    Place, publisher, year, edition, pages
    American Society for Microbiology, 2014
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-105750 (URN)10.1128/JVI.02927-13 (DOI)000332126000010 ()
    Available from: 2014-04-07 Created: 2014-04-04 Last updated: 2017-12-05
    3. The Cholinergic Anti-Inflammatory Pathway Contributes to the Limited Inflammatory Response following Rotavirus Infection
    Open this publication in new window or tab >>The Cholinergic Anti-Inflammatory Pathway Contributes to the Limited Inflammatory Response following Rotavirus Infection
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    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Rotavirus causes acute gastroenteritis in young children and is characterized by severe diarrhoea and vomiting. Surprisingly, although rotavirus infection results in significant intestinal pathology, the inflammatory response is limited. We tested the novel hypothesis that rotavirus infection stimulates the cholinergic anti-inflammatory pathway to suppress gut inflammation. The role of the vagus nerve and the α7 nicotinic acetylcholine receptor (α7 nAChR) in rotavirus infection were explored in α7 nAChR gene-deficient mice, vagotomized mice and wild-type mice treated with the α7 nAChR antagonist mecamylamine. TNF-α, IL-1β and IL-6 were measured in serum, spleen, duodenum, jejunum and ileum at 48 hours post infection. To determine if modulation of the inflammatory response affects virus shedding, α7 nAChRs was blocked and virus quantified in faeces. To investigate if stimulation of α7 nAChRs could attenuate rotavirus toxin NSP4-induced cytokine release, mouse peritoneal- and human blood-macrophages were treated with nicotine before NSP4 stimulation.

    Our results shows that stimulation of the vagus nerve and α7 nAChRs attenuated the pro- inflammatory response during rotavirus infection and blockade of the α7 nAChR reduced virus shedding from infected mice. IL-6 was increased in duodenum (p<0.05) and serum (p<0.05) of vagotomized mice and in jejunum (p<0.05) and spleen (p<0.05) of α7 nAChR gene-deficient mice. Furthermore, IL-6 mRNA (p<0.01) and TNF-α mRNA (p<0.05) were increased in duodenum of vagotomized animals. Similarly, nicotine attenuated the release of TNF-α (p<0.05) and IL-6 (p<0.05) from macrophages stimulated by NSP4 in vitro, all suggesting that the cholinergic anti- inflammatory pathway contributes to attenuate inflammation during rotavirus infection.

    National Category
    Microbiology Cell and Molecular Biology
    Identifiers
    urn:nbn:se:liu:diva-117892 (URN)
    Available from: 2015-05-13 Created: 2015-05-13 Last updated: 2018-01-11Bibliographically approved
    4. Intracellularly expressed rotavirus NSP4 stimulates release of serotonin (5-HT) from human enterochromaffin cells
    Open this publication in new window or tab >>Intracellularly expressed rotavirus NSP4 stimulates release of serotonin (5-HT) from human enterochromaffin cells
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    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Rotavirus (RV) is associated with diarrhoea and vomiting, but the mechanisms behind these symptoms remain unresolved. While RV have been shown to infect and stimulate secretion of serotonin (5-hydroxytryptamine; 5-HT) from human enterochromaffin (EC) cells and to infect EC cells in the small intestine of mice, it remains to identify which intracellularly expressed viral protein (VP) being responsible for this novel property.

    To address this issue, human EC cells were transfected with small interfering RNA (siRNA) targeting the structural (VP4, VP6 and VP7) and the non-structural protein 4 (NSP4) followed by infection with Rhesus rotavirus (RRV). siRNA specific to NSP4 (siRNANSP4) significantly attenuated secretion of 5-HT compared to siRNAVP4, siRNAVP6 , siRNAVP7 and non-targeting (Nt) siRNAnt. Intracellular calcium clamping with BABTA/AM showed that intracellularly expressed NSP4-stimulated secretion of 5-HT from EC cells was calcium-dependent. Furthermore RV down-regulated the 5-HT transporter (SERT) mRNA in ileum but not tryptophan hydroxylase 1 (TPH1) mRNA the rate-limiting enzyme for 5-HT synthesis. The unaffected expression of TPH1 mRNA in the intestinal segments suggests that release of 5- HT primarily originates from pre-made 5-HT rather than from newly synthesised 5-HT mRNA. Moreover, down-regulation of SERT mRNA in ileum presumably resulted in reduced re- uptake of 5-HT by SERT to EC cells and thus increased extracellular 5-HT in the small intestine. Moreover, 7/7 infant mice responded following intraperitoneal administration of 5-HT with rapid (<30 min) diarrhoea in dose-dependent manner. In the light of these results and the fact that both 5-HT and NSP4 can induce diarrhoea in mice, a disease mechanism to RV diarrhoea is proposed.

    National Category
    Microbiology Cell and Molecular Biology
    Identifiers
    urn:nbn:se:liu:diva-117893 (URN)
    Available from: 2015-05-13 Created: 2015-05-13 Last updated: 2018-01-11Bibliographically approved
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  • 208.
    Hagbom, Marie
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Ge, Ray
    School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand.
    Lundin, Samuel
    Department of Microbiology and Immunology, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden.
    Wigzell, Hans
    Microbiology & Tumor biology Center, Karolinska Institute, Stockholm, Sweden.
    Taylor, John A
    School of Biological Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Auckland, New Zealand.
    Andersson, Ulf
    Department of Women's and Children's Health, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    The Cholinergic Anti-Inflammatory Pathway Contributes to the Limited Inflammatory Response following Rotavirus InfectionManuscript (preprint) (Other academic)
    Abstract [en]

    Rotavirus causes acute gastroenteritis in young children and is characterized by severe diarrhoea and vomiting. Surprisingly, although rotavirus infection results in significant intestinal pathology, the inflammatory response is limited. We tested the novel hypothesis that rotavirus infection stimulates the cholinergic anti-inflammatory pathway to suppress gut inflammation. The role of the vagus nerve and the α7 nicotinic acetylcholine receptor (α7 nAChR) in rotavirus infection were explored in α7 nAChR gene-deficient mice, vagotomized mice and wild-type mice treated with the α7 nAChR antagonist mecamylamine. TNF-α, IL-1β and IL-6 were measured in serum, spleen, duodenum, jejunum and ileum at 48 hours post infection. To determine if modulation of the inflammatory response affects virus shedding, α7 nAChRs was blocked and virus quantified in faeces. To investigate if stimulation of α7 nAChRs could attenuate rotavirus toxin NSP4-induced cytokine release, mouse peritoneal- and human blood-macrophages were treated with nicotine before NSP4 stimulation.

    Our results shows that stimulation of the vagus nerve and α7 nAChRs attenuated the pro- inflammatory response during rotavirus infection and blockade of the α7 nAChR reduced virus shedding from infected mice. IL-6 was increased in duodenum (p<0.05) and serum (p<0.05) of vagotomized mice and in jejunum (p<0.05) and spleen (p<0.05) of α7 nAChR gene-deficient mice. Furthermore, IL-6 mRNA (p<0.01) and TNF-α mRNA (p<0.05) were increased in duodenum of vagotomized animals. Similarly, nicotine attenuated the release of TNF-α (p<0.05) and IL-6 (p<0.05) from macrophages stimulated by NSP4 in vitro, all suggesting that the cholinergic anti- inflammatory pathway contributes to attenuate inflammation during rotavirus infection.

  • 209.
    Hagbom, Marie
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Nybom, Rolf
    Karolinska Institute, Sweden.
    Hedlund, Kjell-Olof
    Swedish Institute Communicable Disease Control, Sweden.
    Wigzell, Hans
    Karolinska Institute, Sweden.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Ionizing air affects influenza virus infectivity and prevents airborne-transmission2015In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, no 11431Article in journal (Refereed)
    Abstract [en]

    By the use of a modified ionizer device we describe effective prevention of airborne transmitted influenza A (strain Panama 99) virus infection between animals and inactivation of virus (greater than 97%). Active ionizer prevented 100% (4/4) of guinea pigs from infection. Moreover, the device effectively captured airborne transmitted calicivirus, rotavirus and influenza virus, with recovery rates up to 21% after 40 min in a 19 m(3) room. The ionizer generates negative ions, rendering airborne particles/aerosol droplets negatively charged and electrostatically attracts them to a positively charged collector plate. Trapped viruses are then identified by reverse transcription quantitative real-time PCR. The device enables unique possibilities for rapid and simple removal of virus from air and offers possibilities to simultaneously identify and prevent airborne transmission of viruses.

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  • 210.
    Hagbom, Marie
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Novak, Daniel
    Sahlgrens University Hospital, Sweden.
    Ekstrom, Malin
    Sahlgrens University Hospital, Sweden.
    Khalid, Younis
    Sahlgrens University Hospital, Sweden.
    Andersson, Maria
    University of Gothenburg, Sweden.
    Lindh, Magnus
    University of Gothenburg, Sweden.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Institute, Sweden.
    Ondansetron treatment reduces rotavirus symptoms-A randomized double-blinded placebo-controlled trial2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 10, article id e0186824Article in journal (Refereed)
    Abstract [en]

    Background Rotavirus and norovirus cause acute gastroenteritis with severe diarrhoea and vomiting, symptoms that may lead to severe dehydration and death. The objective of this randomized double-blinded placebo-controlled study was to investigate whether ondansetron, a serotonin receptor antagonist could attenuate rotavirus-and norovirus-induced vomiting and diarrhoea, which would facilitate oral rehydration and possibly accelerate recovery and reduce need for hospitalization. Methods Children with acute gastroenteritis, aged 6 months to 16 years where enrolled (n = 104) and randomized to one single oral dose (0.15mg/kg) of ondansetron (n = 52) or placebo (n = 52). The number of diarrhoea and vomiting episodes during the 24 hours following treatment was reported as well as the number of days with symptoms. Pathogens in faeces were diagnosed by real-time PCR. Outcome parameters were analyzed for rotavirus-and noroviruspositive children. Results One dose of oral ondansetron reduced duration of rotavirus clinical symptoms (p = 0.014), with a median of two days. Furthermore, ondansetron reduced diarrhea episodes, most pronounced in children that had been sick for more than 3 days before treatment (p = 0.028). Conclusion Ondansetron may be a beneficial treatment for children with rotavirus gastroenteritis.

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  • 211. Order onlineBuy this publication >>
    Halling Linder, Cecilia
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Biochemical and functional properties of mammalian bone alkaline phosphatase isoforms during osteogenesis2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The human skeleton is a living and dynamic tissue that constantly is being renewed in a process called bone remodeling. Old bone is resorbed by osteoclasts and new bone is formed by osteoblasts. Bone is a composite material made up by mineral crystals in the form of hydroxyapatite (calcium and phosphate) that provides the hardness of bone, and collagen fibrils that provides elasticity and flexibility. Alkaline phosphatase (ALP) is a family of enzymes that is present in most species and catalyzes the hydrolysis of various phosphomonoesters at alkaline pH. Despite the generalized use of ALP as a biochemical marker of bone formation, the precise function of bone ALP (BALP) is only now becoming clear. Three circulating human BALP isoforms (B1, B2, and B/I) can be distinguished in healthy individuals and a fourth isoform (B1x) has been discovered in patients with chronic kidney disease and in bone tissue.

    Paper I. Three endogenous phosphocompounds, (i.e., inorganic pyrophosphate (PPi), pyridoxal 5′-phosphate (PLP) and phosphoethanolamine (PEA)), have been suggested to serve as  physiological substrates for BALP. The BALP isoforms display different catalytic properties towards PPi and PLP, which is attributed to their distinct N-linked glycosylation patterns. The catalytic activity, using PEA as substrate, was barely detectable for all BALP isoforms indicating that PEA is not a physiological substrate for BALP.

    Paper II. Mouse serum ALP is frequently measured and interpreted in mammalian bone research. However, little is known about the circulating ALPs in mice and their relation to human ALP. We characterized the circulating and tissue-derived mouse ALP isozymes and isoforms from mixed strains of wild-type and knockout mice. All four BALP isoforms (B/I, B1x, B1, and B2) were identified in mouse serum and bone tissues, in good correspondence with those found in human bones. All mouse tissues, except liver, contained significant ALP activities. This is a notable difference as human liver contains vast amounts of ALP.

    Paper III. The objective of this study was to investigate the binding properties of human collagen type I to human BALP, including the two BALP isoforms B1 and B2, together with ALP from human liver, human placenta and E. coli. A surface plasmon resonance-based analysis showed that BALP binds stronger to collagen type I in comparison with ALPs expressed in non-mineralizing tissues. The B2 isoform binds significantly stronger to collagen type I in comparison with the B1 isoform, indicating that glycosylation differences in human ALPs are of crucial importance for protein–protein interactions with collagen type I.

    Paper IV. Tartrate-resistant acid phosphatase (TRAP) is highly expressed in osteoclasts and frequently used as a marker of bone resorption. Intriguingly, recent studies show that TRAP is also expressed in osteoblasts and osteocytes. TRAP displays enzymatic activity towards the endogenous substrates for BALP, i.e., PPi and PLP. Both TRAP and BALP can alleviate the inhibitory effect of osteopontin on mineralization by dephosphorylation, which suggests a novel role for TRAP in skeletal mineralization.

    List of papers
    1. Glycosylation differences contribute to distinct catalytic properties among bone alkaline phosphatase isoforms.
    Open this publication in new window or tab >>Glycosylation differences contribute to distinct catalytic properties among bone alkaline phosphatase isoforms.
    2009 (English)In: Bone, ISSN 1873-2763, Vol. 45, no 5, p. 987-993Article in journal (Refereed) Published
    Abstract [en]

    Three circulating human bone alkaline phosphatase (BALP) isoforms (B1, B2, and B/I) can be distinguished in healthy individuals and a fourth isoform (B1x) has been discovered in patients with chronic kidney disease and in bone tissue. The present study was designed to correlate differing glycosylation patterns of each BALP isoform with their catalytic activity towards presumptive physiological substrates and to compare those properties with two recombinant isoforms of the tissue-nonspecific ALP (TNALP) isozyme, i.e., TNALP-flag, used extensively for mutation analysis of hypophosphatasia mutations and sALP-FcD(10), a chimeric enzyme recently used as therapeutic drug in a mouse model of infantile hypophosphatasia. The BALP isoforms were prepared from human osteosarcoma (SaOS-2) cells and the kinetic properties were evaluated using the synthetic substrate p-nitrophenylphosphate (pNPP) at pH 7.4 and 9.8, and the three suggested endogenous physiological substrates, i.e., inorganic pyrophosphate (PP(i)), pyridoxal 5'-phosphate (PLP), and phosphoethanolamine (PEA) at pH 7.4. Qualitative glycosylation differences were also assessed by lectin binding and precipitation. The k(cat)/K(M) was higher for B2 for all the investigated substrates. The catalytic activity towards PEA was essentially undetectable. The kinetic activity for TNALP-flag and sALP-FcD(10) was similar to the activity of the human BALP isoforms. The BALP isoforms differed in their lectin binding properties and dose-dependent lectin precipitation, which also demonstrated differences between native and denatured BALP isoforms. The observed differences in lectin specificity were attributed to N-linked carbohydrates. In conclusion, we demonstrate significantly different catalytic properties among the BALP isoforms due to structural differences in posttranslational glycosylation. Our data also suggests that PEA is not an endogenous substrate for the BALP isoforms or for the recombinant TNALP isoforms. The TNALP-flag and the sALP-FcD(10) isoforms faithfully mimic the biological properties of the human BALP isoforms in vivo validating the use of these recombinant enzymes in studies aimed at dissecting the pathophysiology and treating hypophosphatasia.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-21351 (URN)10.1016/j.bone.2009.07.009 (DOI)19631305 (PubMedID)
    Available from: 2009-10-01 Created: 2009-10-01 Last updated: 2016-04-14
    2. Isozyme profile and tissue-origin of alkaline phosphatases in mouse serum
    Open this publication in new window or tab >>Isozyme profile and tissue-origin of alkaline phosphatases in mouse serum
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    2013 (English)In: Bone, ISSN 8756-3282, E-ISSN 1873-2763, Vol. 53, no 2, p. 399-408Article in journal (Refereed) Published
    Abstract [en]

    Mouse serum alkaline phosphatase (ALP) is frequently measured and interpreted in mammalian bone research. However, little is known about the circulating ALPs in mice and their relation to human ALP isozymes and isoforms. Mouse ALP was extracted from liver, kidney, intestine, and bone from vertebra, femur and calvaria tissues. Serum from mixed strains of wild-type (WT) mice and from individual ALP knockout strains were investigated, i.e., Alpl(-/-) (a.k.a. Akp2 encoding tissue-nonspecific ALP or TNALP), Akp3(-/-) (encoding duodenum-specific intestinal ALP or dIALP), and Alpi(-/-) (a.k.a. Akp6 encoding global intestinal ALP or gIALP). The ALP isozymes and isoforms were identified by various techniques and quantified by high-performance liquid chromatography. Results from the WT and knockout mouse models revealed identical bone-specific ALP isoforms (B/I. B1, and B2) as found in human serum, but in addition mouse serum contains the B1x isoform only detected earlier in patients with chronic kidney disease and in human bone tissue. The two murine intestinal isozymes, dIALP and gIALP, were also identified in mouse serum. All four bone-specific ALP isoforms (B/I, B1x, B1, and B2) were identified in mouse bones, in good correspondence with those found in human bones. All mouse tissues, except liver and colon, contained significant ALP activities. This is a notable difference as human liver contains vast amounts of ALP. Histochemical staining, Northern and Western blot analyses confirmed undetectable ALP expression in liver tissue. ALP activity staining showed some positive staining in the bile canaliculi for BALB/c and FVB/N WT mice, but not in C57BI/6 and ICR mice. Taken together, while the main source of ALP in human serum originates from bone and liver, and a small fraction from intestine (andlt;5%), mouse serum consists mostly of bone ALP, including all four isoforms, B/I, B1x, B1, and B2, and two intestinal ALP isozymes dIALP and gIALR We suggest that the genetic nomenclature for the Alpl gene in mice (i.e., ALP liver) should be reconsidered since murine liver has undetectable amounts of ALP activity. These findings should pave the way for the development of user-friendly assays measuring circulating bone-specific ALP in mouse models used in bone and mineral research.

    Place, publisher, year, edition, pages
    Elsevier, 2013
    Keywords
    Alkaline phosphatase, Bone, Glycosylation, Hypophosphatasia, Knockout mice, Mineralization
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-90744 (URN)10.1016/j.bone.2012.12.048 (DOI)000315763700010 ()
    Note

    Funding Agencies|County Council of Ostergotland in Sweden||National Institutes of Health, USA|DE012889|

    Available from: 2013-04-05 Created: 2013-04-05 Last updated: 2017-12-06
    3. Glycation Contributes to Interaction Between Human Bone Alkaline Phosphatase and Collagen Type I
    Open this publication in new window or tab >>Glycation Contributes to Interaction Between Human Bone Alkaline Phosphatase and Collagen Type I
    2016 (English)In: Calcified Tissue International, ISSN 0171-967X, E-ISSN 1432-0827, Vol. 98, no 3, p. 284-293Article in journal (Refereed) Published
    Abstract [en]

    Bone is a biological composite material comprised primarily of collagen type I and mineral crystals of calcium and phosphate in the form of hydroxyapatite (HA), which together provide its mechanical properties. Bone alkaline phosphatase (ALP), produced by osteoblasts, plays a pivotal role in the mineralization process. Affinity contacts between collagen, mainly type II, and the crown domain of various ALP isozymes were reported in a few in vitro studies in the 1980s and 1990s, but have not attracted much attention since, although such interactions may have important implications for the bone mineralization process. The objective of this study was to investigate the binding properties of human collagen type I to human bone ALP, including the two bone ALP isoforms B1 and B2. ALP from human liver, human placenta and E. coli were also studied. A surface plasmon resonance-based analysis, supported by electrophoresis and blotting, showed that bone ALP binds stronger to collagen type I in comparison with ALPs expressed in non-mineralizing tissues. Further, the B2 isoform binds significantly stronger to collagen type I in comparison with the B1 isoform. Human bone and liver ALP (with identical amino acid composition) displayed pronounced differences in binding, revealing that post-translational glycosylation properties govern these interactions to a large extent. In conclusion, this study presents the first evidence that glycosylation differences in human ALPs are of crucial importance for protein–protein interactions with collagen type I, although the presence of the ALP crown domain may also be necessary. Different binding affinities among the bone ALP isoforms may influence the mineral-collagen interface, mineralization kinetics, and degree of bone matrix mineralization, which are important factors determining the material properties of bone.

    Place, publisher, year, edition, pages
    Springer-Verlag New York, 2016
    Keywords
    Alkaline phosphatase; Bone; Collagen; Glycosylation; Mineralization; Surface plasmon resonance
    National Category
    Endocrinology and Diabetes Dentistry
    Identifiers
    urn:nbn:se:liu:diva-127099 (URN)10.1007/s00223-015-0088-0 (DOI)000373744700008 ()26645431 (PubMedID)
    Note

    Funding agencies:  Region Ostergotland, Sweden

    Available from: 2016-04-14 Created: 2016-04-14 Last updated: 2017-11-30Bibliographically approved
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  • 212.
    Halling Linder, Cecilia
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Ek-Rylander, Barbro
    Karolinska Institute, Sweden.
    Krumpel, Michael
    Karolinska Institute, Sweden.
    Norgard, Maria
    Karolinska Institute, Sweden.
    Narisawa, Sonoko
    Sanford Childrens Health Research Centre, CA 92037 USA.
    Luis Millan, Jose
    Sanford Childrens Health Research Centre, CA 92037 USA.
    Andersson, Göran
    Karolinska Institute, Sweden.
    Magnusson, Per
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Bone Alkaline Phosphatase and Tartrate-Resistant Acid Phosphatase: Potential Co-regulators of Bone Mineralization2017In: Calcified Tissue International, ISSN 0171-967X, E-ISSN 1432-0827, Vol. 101, no 1, p. 92-101Article in journal (Refereed)
    Abstract [en]

    Phosphorylated osteopontin (OPN) inhibits hydroxyapatite crystal formation and growth, and bone alkaline phosphatase (BALP) promotes extracellular mineralization via the release of inorganic phosphate from the mineralization inhibitor inorganic pyrophosphate (PPi). Tartrate-resistant acid phosphatase (TRAP), produced by osteoclasts, osteoblasts, and osteocytes, exhibits potent phosphatase activity towards OPN; however, its potential capacity as a regulator of mineralization has not previously been addressed. We compared the efficiency of BALP and TRAP towards the endogenous substrates for BALP, i.e., PPi and pyridoxal 5-phosphate (PLP), and their impact on mineralization in vitro via dephosphorylation of bovine milk OPN. TRAP showed higher phosphatase activity towards phosphorylated OPN and PPi compared to BALP, whereas the activity of TRAP and BALP towards PLP was comparable. Bovine milk OPN could be completely dephosphorylated by TRAP, liberating all its 28 phosphates, whereas BALP dephosphorylated at most 10 phosphates. OPN, dephosphorylated by either BALP or TRAP, showed a partially or completely attenuated phosphorylation-dependent inhibitory capacity, respectively, compared to native OPN on the formation of mineralized nodules. Thus, there are phosphorylations in OPN important for inhibition of mineralization that are removed by TRAP but not by BALP. In conclusion, our data indicate that both BALP and TRAP can alleviate the inhibitory effect of OPN on mineralization, suggesting a potential role for TRAP in skeletal mineralization. Further studies are warranted to explore the possible physiological relevance of TRAP in bone mineralization.

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  • 213.
    Halling Linder, Cecilia
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry.
    Enander, Karin
    Linköping University, Department of Physics, Chemistry and Biology, Molecular Physics. Linköping University, Faculty of Science & Engineering.
    Magnusson, Per
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Glycation Contributes to Interaction Between Human Bone Alkaline Phosphatase and Collagen Type I2016In: Calcified Tissue International, ISSN 0171-967X, E-ISSN 1432-0827, Vol. 98, no 3, p. 284-293Article in journal (Refereed)
    Abstract [en]

    Bone is a biological composite material comprised primarily of collagen type I and mineral crystals of calcium and phosphate in the form of hydroxyapatite (HA), which together provide its mechanical properties. Bone alkaline phosphatase (ALP), produced by osteoblasts, plays a pivotal role in the mineralization process. Affinity contacts between collagen, mainly type II, and the crown domain of various ALP isozymes were reported in a few in vitro studies in the 1980s and 1990s, but have not attracted much attention since, although such interactions may have important implications for the bone mineralization process. The objective of this study was to investigate the binding properties of human collagen type I to human bone ALP, including the two bone ALP isoforms B1 and B2. ALP from human liver, human placenta and E. coli were also studied. A surface plasmon resonance-based analysis, supported by electrophoresis and blotting, showed that bone ALP binds stronger to collagen type I in comparison with ALPs expressed in non-mineralizing tissues. Further, the B2 isoform binds significantly stronger to collagen type I in comparison with the B1 isoform. Human bone and liver ALP (with identical amino acid composition) displayed pronounced differences in binding, revealing that post-translational glycosylation properties govern these interactions to a large extent. In conclusion, this study presents the first evidence that glycosylation differences in human ALPs are of crucial importance for protein–protein interactions with collagen type I, although the presence of the ALP crown domain may also be necessary. Different binding affinities among the bone ALP isoforms may influence the mineral-collagen interface, mineralization kinetics, and degree of bone matrix mineralization, which are important factors determining the material properties of bone.

  • 214. Order onlineBuy this publication >>
    Halvarsson, Camilla
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Hypoxia inducible factor 1 alpha: dependent and independent regulation of hematopoietic stem cells and leukemia2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis has studied the role of low oxygen levels, or hypoxia, in hematopoietic stem cells (HSCs) and how, at the molecular level, it regulates stem cell maintenance and protects against oxidative stress induced by reactive oxygen species (ROS). HSCs reside within the bone marrow in specific niches created by a unique vascularized environment, which is suggested to be hypoxic and crucial for HSCs by maintaining a quiescent state of cell cycle and by redirecting metabolism away from the mitochondria to glycolysis. The niches are also believed to limit the production of ROS, which could damage DNA and disrupt the stem cell features. The hypoxia-responsive protein hypoxia-inducible factor 1 alpha (HIF-1α) is a major regulator of the hypoxic cell response in HSCs as well as in leukemic stem cells. Both these cells are thought to reside in the bone marrow where they are protected from stress and chemotherapy by niche cells and hypoxia.

    The thesis demonstrates that pyruvate dehydrogenase kinase 1 regulates a metabolic shift to glycolysis, and maintains the engraftment potential of both HSCs and multipotent progenitors upon transplantation. Furthermore, we wanted to determine whether HIF-1α or other signaling pathways are involved in protecting HSCs from ROS-induced cell death. Overexpression, silencing or a knockout mouse model of Hif-1α could not identify HIF-1α as important for protecting HSCs from oxidative stress-induced cell death through inhibition of synthesis of the antioxidant glutathione. Gene expression analysis instead identified the transcription factor nuclear factor kappa B (NF-κB) as induced by hypoxia. By studying NF- κB signaling we found increased NF-κB activity in cells cultured in hypoxia compared to normoxia. Suppression of inhibitor of kappa B indicated a putative role of NF-κB signaling in hypoxia-induced protection against oxidative stress. The findings show that hypoxia-induced protection to elevated levels of ROS upon glutathione depletion seems to be attributed to activation of the NF-κB signaling pathway independently of HIF-1α.

    To address the question whether hypoxic in vitro cultures support maintenance and promote HSC expansion we performed a limited dilution-transplantation assay. Our data indicate that hypoxic cultures maintain more long-term-reconstituting HSCs than normoxia, but this could not be confirmed statistically. Finally, we wanted to study the mechanisms by which hypoxia protect against chemotherapy. We could demonstrate that hypoxic culture protects leukemic cell lines against apoptosis induced by chemotherapy or inhibitors used for treatment of leukemia. This multidrug resistance seems to be mediated by ATP-binding cassette transporter genes, which are upregulated by hypoxia and whose inhibition has been shown to increase chemosensitivity. In addition, HIF-1α was upregulated in the leukemic cell lines in hypoxia and its inhibition increased the sensitivity to chemotherapy, indicating a role in inducing chemotherapy resistance.

    Conclusively, the results presented in this thesis stress the importance of hypoxia in regulating metabolism, oxidative-stress response and maintenance of both HSCs as well as leukemic cells, especially through the critical transcription factors HIF-1α and NF-κB and their target genes.  

    List of papers
    1. Pyruvate dehydrogenase kinase 1 is essential for transplantable mouse bone marrow hematopoietic stem cell and progenitor function
    Open this publication in new window or tab >>Pyruvate dehydrogenase kinase 1 is essential for transplantable mouse bone marrow hematopoietic stem cell and progenitor function
    2017 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 2, article id e0171714Article in journal (Refereed) Published
    Abstract [en]

    Background Accumulating evidence suggests that hypoxic areas in the bone marrow are crucial for maintenance of hematopoietic stem cells (HSCs) by supporting a quiescent state of cell cycle and regulating the transplantation capacity of long-term (LT)-HSCs. In addition, HSCs seem to express a metabolic profile of energy production away from mitochondrial oxidative phosphorylation in favor of glycolysis. At oxygen deprivation, hypoxia inducible factor 1 alpha (HIF-1 alpha) is known to induce glycolytic enzymes as well as suppressing mitochondrial energy production by inducing pyruvate dehydrogenase kinase 1 (Pdk1) in most cell types. It has not been established whether PDK1 is essential for HSC function and mediates hypoxia-adapting functions in HSCs. While the Pdk gene family contains four members (Pdk1-4), it was recently shown that Pdk2 and Pdk4 have an important role in regulating LT-HSCs. Principle findings Here we demonstrate that PDK1 activity is crucial for transplantable HSC function. Whereas Pdkl, Pdk2, and Pdk3 transcripts were expressed at higher levels in different subtypes of HSCs compared to differentiated cells, we could not detect any major differences in expression between LT-HSCs and more short-term HSCs and multipotent progenitors. When studying HIF-1 alpha-mediated regulation of Pdk activity in vitro, Pdk1 was the most robust target regulated by hypoxia, whereas Pdk2, Pdk3, and Pdk4 were not affected. Contrary, genetic ablation in a cre-inducible Hif-1 alpha knockout mouse did not support a link between HIF-1 alpha and Pdk1. Silencing of Pdk1 by shRNA lentiviral gene transfer partially impaired progenitor colony formation in vitro and had a strong negative effect on both long-term and short-term engraftment in mice. Conclusions Our study demonstrates that PDK1 has broad effects in hematopoiesis and is a critical factor for engraftment of both HSCs and multipotent progenitors upon transplantation to recipient mice. While Pdk1 was a robust hypoxia-inducible gene mediated by HIF-1 alpha in vitro, we could not find evidence of any in vivo links between Pdk1 and HIF-1 alpha.

    Place, publisher, year, edition, pages
    PUBLIC LIBRARY SCIENCE, 2017
    National Category
    Cell and Molecular Biology
    Identifiers
    urn:nbn:se:liu:diva-136062 (URN)10.1371/journal.pone.0171714 (DOI)000394231800095 ()28182733 (PubMedID)
    Note

    Funding Agencies|Swedish Research Council; Swedish Cancer Society; Swedish Childhood Cancer Foundation; County Council of Ostergotland; Faculty of Medicine at Linkoping University; Ollie and Elof Ericssons Foundation

    Available from: 2017-03-27 Created: 2017-03-27 Last updated: 2018-10-18
    2. Putative Role of Nuclear Factor-Kappa B But Not Hypoxia-Inducible Factor-1α in Hypoxia-Dependent Regulation of Oxidative Stress in Hematopoietic Stem and Progenitor Cells
    Open this publication in new window or tab >>Putative Role of Nuclear Factor-Kappa B But Not Hypoxia-Inducible Factor-1α in Hypoxia-Dependent Regulation of Oxidative Stress in Hematopoietic Stem and Progenitor Cells
    Show others...
    2019 (English)In: Antioxidants and Redox Signaling, ISSN 1523-0864, E-ISSN 1557-7716, Vol. 31, no 3, p. 211-226Article in journal (Refereed) Published
    Abstract [en]

    Aims: Adaptation to low oxygen of hematopoietic stem cells (HSCs) in the bone marrow has been demonstrated to depend on the activation of hypoxia-inducible factor (HIF)-1α as well as the limited production of reactive oxygen species (ROS). In this study, we aimed at determining whether HIF-1α is involved in protecting HSCs from ROS.

    Results: Oxidative stress was induced by DL-buthionine-(S,R)-sulfoximine (BSO)-treatment, which increases the mitochondrial ROS level. Hypoxia rescued Lineage-Sca-1+c-kit+ (LSK) cells from BSO-induced apoptosis, whereas cells succumbed to apoptosis in normoxia. Apoptosis in normoxia was inhibited with the antioxidant N-acetyl-L-cysteine or by overexpression of anti-apoptotic BCL-2. Moreover, stabilized expression of oxygen-insensitive HIFs could not protect LSK cells from oxidative stress-induced apoptosis at normoxia, neither could short hairpin RNA to Hif-1α inhibit the protective effects by hypoxia in LSK cells. Likewise, BSO treatment of LSK cells from Hif-1α knockout mice did not suppress the effects seen in hypoxia. Microarray analysis identified the nuclear factor-kappa B (NF-κB) pathway as a pathway induced by hypoxia. By using NF-κB lentiviral construct and DNA-binding assay, we found increased NF-κB activity in cells cultured in hypoxia compared with normoxia. Using an inhibitor against NF-κB activation, we could confirm the involvement of NF-κB signaling as BSO-mediated cell death was significantly increased in hypoxia after adding the inhibitor.

    Innovation: HIF-1α is not involved in protecting HSCs and progenitors to elevated levels of ROS on glutathione depletion during hypoxic conditions.

    Conclusion: The study proposes a putative role of NF-κB signaling as a hypoxia-induced regulator in early hematopoietic cells.

    Place, publisher, year, edition, pages
    Mary Ann Liebert, 2019
    Keywords
    hematopoiesis, hypoxia, oxidative stress, glutathione, mitochondria, NF-κB
    National Category
    Cell and Molecular Biology Cell Biology Immunology
    Identifiers
    urn:nbn:se:liu:diva-156661 (URN)10.1089/ars.2018.7551 (DOI)000464553400001 ()30827134 (PubMedID)
    Note

    Funding agencies: Swedish Research Council; Swedish Cancer Foundation; Swedish Childrens Cancer Foundation; County Council of Ostergotland

    Available from: 2019-05-06 Created: 2019-05-06 Last updated: 2019-10-17Bibliographically approved
    3. Letter: Hypoxic and normoxic in vitro cultures maintain similar numbers of long-term reconstituting hematopoietic stem cells from mouse bone marrow
    Open this publication in new window or tab >>Letter: Hypoxic and normoxic in vitro cultures maintain similar numbers of long-term reconstituting hematopoietic stem cells from mouse bone marrow
    2012 (English)In: Experimental Hematology, ISSN 0301-472X, E-ISSN 1873-2399, Vol. 40, no 11, p. 879-881Article in journal, Letter (Other academic) Published
    Abstract [en]

    n/a

    Place, publisher, year, edition, pages
    Elsevier, 2012
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-85627 (URN)10.1016/j.exphem.2012.07.005 (DOI)000310182400001 ()
    Available from: 2012-11-26 Created: 2012-11-26 Last updated: 2018-10-18
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  • 215.
    Halvarsson, Camilla
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Eliasson, Pernilla M.
    Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology.
    Jönsson, Jan-Ingvar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Pyruvate dehydrogenase kinase 1 is essential for transplantable mouse bone marrow hematopoietic stem cell and progenitor function2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 2, article id e0171714Article in journal (Refereed)
    Abstract [en]

    Background Accumulating evidence suggests that hypoxic areas in the bone marrow are crucial for maintenance of hematopoietic stem cells (HSCs) by supporting a quiescent state of cell cycle and regulating the transplantation capacity of long-term (LT)-HSCs. In addition, HSCs seem to express a metabolic profile of energy production away from mitochondrial oxidative phosphorylation in favor of glycolysis. At oxygen deprivation, hypoxia inducible factor 1 alpha (HIF-1 alpha) is known to induce glycolytic enzymes as well as suppressing mitochondrial energy production by inducing pyruvate dehydrogenase kinase 1 (Pdk1) in most cell types. It has not been established whether PDK1 is essential for HSC function and mediates hypoxia-adapting functions in HSCs. While the Pdk gene family contains four members (Pdk1-4), it was recently shown that Pdk2 and Pdk4 have an important role in regulating LT-HSCs. Principle findings Here we demonstrate that PDK1 activity is crucial for transplantable HSC function. Whereas Pdkl, Pdk2, and Pdk3 transcripts were expressed at higher levels in different subtypes of HSCs compared to differentiated cells, we could not detect any major differences in expression between LT-HSCs and more short-term HSCs and multipotent progenitors. When studying HIF-1 alpha-mediated regulation of Pdk activity in vitro, Pdk1 was the most robust target regulated by hypoxia, whereas Pdk2, Pdk3, and Pdk4 were not affected. Contrary, genetic ablation in a cre-inducible Hif-1 alpha knockout mouse did not support a link between HIF-1 alpha and Pdk1. Silencing of Pdk1 by shRNA lentiviral gene transfer partially impaired progenitor colony formation in vitro and had a strong negative effect on both long-term and short-term engraftment in mice. Conclusions Our study demonstrates that PDK1 has broad effects in hematopoiesis and is a critical factor for engraftment of both HSCs and multipotent progenitors upon transplantation to recipient mice. While Pdk1 was a robust hypoxia-inducible gene mediated by HIF-1 alpha in vitro, we could not find evidence of any in vivo links between Pdk1 and HIF-1 alpha.

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    fulltext
  • 216.
    Hamad, Tarza
    et al.
    University of Örebro, Sweden.
    Hellmark, Bengt
    University of Örebro, Sweden.
    Nilsdotter-Augustinsson, Åsa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Infectious Diseases.
    Soderquist, Bo
    University of Örebro, Sweden.
    Antibiotic susceptibility among Staphylococcus epidermidis isolated from prosthetic joint infections, with focus on doxycycline2015In: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS), ISSN 0903-4641, E-ISSN 1600-0463, Vol. 123, no 12, p. 1055-1060Article in journal (Refereed)
    Abstract [en]

    In recent years, coagulase-negative staphylococci such as Staphylococcus epidermidis have gained importance as nosocomial pathogens, especially in immunocompromised patients and prosthetic joint infections (PJIs). These infections are often long lasting and difficult to treat due to the production of bacterial biofilm and the transformation of the bacteria into a stationary growth phase. Rifampicin is able to penetrate the biofilm, but to reduce the risk of development of rifampicin resistance it should be used in combination with an additional antibiotic. In this study we used Etest to investigate the antimicrobial susceptibility of 134 clinical isolates of S.epidermidis obtained from PJIs to six oral antibiotics: doxycycline, rifampicin, linezolid, fusidic acid, clindamycin, and ciprofloxacin. We also performed synergy testing on doxycycline in combination with each of the remaining antibiotics. Ninety-three (69%) of the 134 isolates were susceptible to doxycycline, 94/134 (70%) to rifampicin, 56/134 (42%) to clindamycin, 25/134 (19%) to ciprofloxacin, 81/134 (60%) to fusidic acid, and 100% to linezolid. Thirty-two (80%) of the 40 isolates not fully susceptible to rifampicin were susceptible to doxycycline. Doxycycline in combination with each of the other investigated antibiotics exerted an additive effect on nearly half of the isolates, with the exception of clindamycin, which displayed an even higher percentage of additive effect (69%). To conclude, as the majority of the S.epidermidis isolates were susceptible to doxycycline, this antimicrobial agent may provide a potential alternative for combination therapy together with rifampicin.

  • 217.
    Hammar, Mats
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Children's and Women's health. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, Department of Gynaecology and Obstetrics in Linköping.
    Larsson, Erika
    Linköping University, Department of Clinical and Experimental Medicine, Division of Children's and Women's health. Linköping University, Faculty of Medicine and Health Sciences.
    Bladh, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Children's and Women's health. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, Department of Gynaecology and Obstetrics in Linköping.
    Finnström, Orvar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Children's and Women's health. Linköping University, Faculty of Medicine and Health Sciences.
    Gäddlin, Per-Olof
    Linköping University, Department of Clinical and Experimental Medicine, Division of Children's and Women's health. Linköping University, Faculty of Medicine and Health Sciences.
    Leijon, Ingemar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Children's and Women's health. Linköping University, Faculty of Medicine and Health Sciences.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Sydsjö, Gunilla
    Linköping University, Department of Clinical and Experimental Medicine, Division of Children's and Women's health. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, Department of Gynaecology and Obstetrics in Linköping.
    A long-term follow-up study of men born with very low birth weight and their reproductive hormone profile2018In: Systems biology in reproductive medicine, ISSN 1939-6376, Vol. 64, no 3, p. 207-215Article in journal (Refereed)
    Abstract [en]

    Environmental factors during the fetal period may adversely affect reproductive functions in men being born with very low birth weight (VLBW, <1500 g). The objective of this prospective, controlled cohort study was to investigate if VLBW men have an altered reproductive hormone profile compared with men born at term. The study group initially consisted of all VLBW boys live-born between 1 February 1987 and 30 April 1988 in the south-east region of Sweden (n = 47). A control child was chosen born at term, at the same hospital, with the same parity, without malformations, and next in order after each VLBW child who survived the first four weeks (n = 45). The present follow-up was performed when the men were 26-28 years of age and included measurements of serum hormone levels, hair testosterone concentration, and anthropometric data. Also life-style questionnaires were collected from 26 VLBW men and 19 controls. The VLBW group (n = 26) had higher median levels of serum estradiol, 84.5 pmol/L than controls (n = 19), 57.5 pmol/L (p = 0.008). There was no significant correlation between serum estradiol and BMI (r = 0.06, p = 0.74). There were no differences in other hormone levels or the reproductive pattern between the groups. In conclusion, even though there was a statistically significant difference in estradiol levels between the groups, both groups had low normal mean levels of questionable clinical significance. The reproductive pattern was similar in the two groups and in this study being born VLBW does not seem to affect these measured aspects of reproduction.

    ABBREVIATIONS: ADHD: attention deficit hyperactive disorder; AGA: average for gestational age; BMI: body mass index; CP: cerebral palsy; DHT: dihydrotestosterone; FSH: follicle stimulating hormone; LBW: low birth weight; LH: luteinizing hormone; SAD: sagittal abdominal diameter; SGA: small for gestational age; SHBG: sex hormone binding globulin; TSH: thyroid stimulating hormone; T3: triiodothyronine; T4: thyroxin; VLBW: very low birth weight.

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  • 218.
    Hammarskjold, F
    et al.
    Ryhov County Hospital, Sweden .
    Mernelius, S
    Ryhov County Hospital, Sweden .
    Andersson, R. E.
    Ryhov County Hospital, Sweden .
    Berg, Sören
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Hanberger, Håkan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Infectious Diseases.
    Lofgren, S
    Ryhov County Hospital, Sweden .
    Malmvall, Bo-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Infectious Diseases. Linköping University, Faculty of Health Sciences.
    Petzold, M
    University of Gothenburg, Sweden .
    Matussek, A
    Ryhov County Hospital, Sweden .
    Possible transmission of Candida albicans on an intensive care unit: genotype and temporal cluster analyses2013In: Journal of Hospital Infection, ISSN 0195-6701, E-ISSN 1532-2939, Vol. 85, no 1, p. 60-65Article in journal (Refereed)
    Abstract [en]

    Background: Nosocomial transmission of Candida spp. has not been fully explored and previous studies have shown conflicting results. less thanbrgreater than less thanbrgreater thanAim: To evaluate the possible nosocomial transmission of Candida spp. on an intensive care unit (ICU). less thanbrgreater than less thanbrgreater thanMethods: A prospective study was conducted for a period of 19 months, including all patients on our ICU with growth of Candida spp. from surveillance and directed cultures. Molecular typing with repetitive sequence-based polymerase chain reaction was used to define genotype relationships between the Candida albicans and Candida glabrata isolates. Candida isolates obtained from blood cultures taken from patients in our county outside the ICU were used as a reference. Temporal cluster analysis was performed to evaluate genotype distribution over time. less thanbrgreater than less thanbrgreater thanFindings: Seventy-seven patients with 78 ICU stays, representing 12% of all ICU stays, were found to harbour 180 isolates of Candida spp. Molecular typing revealed 27 C. albicans genotypes and 10 of C. glabrata. Possible clustering, indicated by overlapping stays of patients with indistinguishable candida genotypes, was observed on seven occasions with C. albicans and on two occasions with C. glabrata. Two C. albicans genotypes were found significantly more often in the ICU group compared with the reference group. Moreover, C. albicans genotypes isolated from more than one patient were significantly more often found in the ICU group. Temporal cluster analysis revealed a significantly increased number of pairs with indistinguishable genotypes at a 21-day interval, indicating clustering. less thanbrgreater than less thanbrgreater thanConclusion: This study indicates possible transmission of C. albicans between ICU patients based on genotyping and temporal cluster analysis.

  • 219.
    Hammarskjöld, Fredrik
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Berg, Sören
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Hanberger, Håkan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Infectious Diseases.
    Taxbro, Knut
    Ryhov County Hospital, Sweden .
    Malmvall, Bo-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Jonkoping Cty Council, Futurum Acad Hlth Care, Jonkoping, Sweden.
    Sustained low incidence of central venous catheter-related infections over six years in a Swedish hospital with an active central venous catheter team2014In: American Journal of Infection Control, ISSN 0196-6553, E-ISSN 1527-3296, Vol. 42, no 2, p. 122-128Article in journal (Refereed)
    Abstract [en]

    Background: There are limited data on the long-term effects of implementing a central venous catheter (CVC) program for prevention of CVC infections. The aims of this study were to evaluate the incidence of CVC colonization, catheter-related infections (CRI), catheter-related bloodstream infections (CRBSI), and their risk factors over a 6-year period in a hospital with an active CVC team. Methods: We conducted a continuous prospective study aiming to include all CVCs used at our hospital during the years 2004 to 2009, evaluating colonization, CRI, CRBSI, and possible risk factors. Results: A total of 2,772 CVCs was used during the study period. Data on culture results and catheterization time were available for 2,045 CVCs used in 1,674 patients. The incidences of colonization, CRI, and CRBSI were 7.0, 2.2, and 0.6 per 1,000 CVC-days, respectively. Analysis of quarterly incidences revealed 1 occasion with increasing infection rates. Catheterization time was a risk factor for CRI but not for CRBSI. Other risk factors for CRI were hemodialysis and CVC use in the internal jugular vein compared with the subclavian vein. Hemodialysis was the only risk factor for CRBSI. Conclusion: We found that a CRI prevention program led by an active CVC team and adhered to by the entire staff at a county hospital is successful in keeping CVC infections at a low rate over a long period of time.

  • 220.
    Hammarsten, Ola
    et al.
    Avdelningen för Laboratoriemedicin vid Institutionen för biomedicin, Göteborgs universitet.
    Grankvist, Kjell
    Institutionen för medicinsk biovetenskap, Umeå universitet.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Tolkning av analysresultat2018In: Laurells klinisk kemi i praktisk medicin / [ed] Elvar Theodorsson, Maria Berggren Söderlund, Lund: Studentlitteratur AB, 2018, 10, p. 31-54Chapter in book (Other academic)
  • 221.
    Hammarsten, Ola
    et al.
    University of Gothenburg, Sweden.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Bjurman, Christian
    University of Gothenburg, Sweden.
    Petzold, Max
    University of Gothenburg, Sweden.
    Risk of myocardial infarction at specific troponin T levels using the parameter predictive value among lookalikes (PAL)2017In: Clinical Biochemistry, ISSN 0009-9120, E-ISSN 1873-2933, Vol. 50, no 1-2Article in journal (Refereed)
    Abstract [en]

    Background: Myocardial infarction is more likely if the heart damage biomarker cardiac troponin T (cTnT) is elevated in a blood sample, indicating that cardiac damage has occurred. No method allows the clinician to estimate the risk of myocardial infarction at a specific cTnT level in a given patient. Methods: Predictive value among lookalikes (PAL) uses pre-test prevalence, sensitivity and specificity at adjacent cTnT limits based on percentiles. PAL is the pre-test prevalence-adjusted probability of disease between two adjacent cTnT limits. If a chest pain patients cTnT level is between these limits, the risk of myocardial infarction can be estimated. Results: The PAL based on percentiles had an acceptable sampling error when using 100 bootstrapped data of 18 different biomarkers from 38,945 authentic lab measurements. A PAL analysis of an emergency room cohort (n = 11,020) revealed that the diagnostic precision of a high-sensitive cTnT assay was similar among chest pain patients at different ages. The higher incidence of false positive results due to non-specific increases in cTnT in the high-age group was counterbalanced by a higher pre-test prevalence of myocardial infarction among older patients, a finding that was missed when using a conventional ROC plot analysis. Conclusions: The PAL was able to calculate the risk of myocardial infarction at specific cTnT levels and could complement decision limits. 2016 The Authors. The Canadian Society of Clinical Chemists. Published by Elsevier Inc.

  • 222.
    Hamzik, Namik
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences.
    Tang, Yan-juan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences.
    Eskilsson, Anna
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences.
    Örtegren Kugelberg, Unn
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences.
    Ruud, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences.
    Jönsson, Jan-Ingvar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Blomqvist, Anders
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences.
    Nilsberth, Camilla
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences.
    Interleukin-6 primarily produced by non-hematopoietic cells mediates the lipopolysaccharide-induced febrile response2013In: Brain, behavior, and immunity, ISSN 0889-1591, E-ISSN 1090-2139, Vol. 33, p. 123-130Article in journal (Refereed)
    Abstract [en]

    Interleukin-6 (IL-6) is critical for the lipopolysaccharide (LPS)-induced febrile response. However, the exact source(s) of IL-6 involved in regulating the LPS-elicited fever is still to be identified. One known source of IL-6 is hematopoietic cells, such as monocytes. To clarify the contribution of hematopoietically derived IL-6 to fever, we created chimeric mice expressing IL-6 selectively either in cells of hematopoietic or, conversely, in cells of non-hematopoietic origin. This was performed by extinguishing hematopoietic cells in wild-type (WT) or IL-6 knockout (IL-6 KO) mice by whole-body irradiation and transplanting them with new stem cells. Mice on a WT background but lacking IL-6 in hematopoietic cells displayed normal fever to LPS and were found to have similar levels of IL-6 protein in the cerebrospinal fluid (CSF) and in plasma and of IL-6 mRNA in the brain as WT mice. In contrast, mice on an IL-6 KO background, but with intact IL-6 production in cells of hematopoietic origin, only showed a minor elevation of the body temperature after peripheral LPS injection. While they displayed significantly elevated levels of IL-6 both in plasma and CSF compared with control mice, the increase was modest compared with that seen in LPS injected mice on a WT background, the latter being approximately 20 times larger in magnitude. These results suggest that IL-6 of non-hematopoietic origin is the main source of IL-6 in LPS-induced fever, and that IL-6 produced by hematopoietic cells only plays a minor role.

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  • 223.
    Hanberger, Håkan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Infectious Diseases.
    Sepsis på akuten & IVA: Diagnostik och Antibiotikaterapi2017Collection (editor) (Other academic)
    Abstract [sv]

    Tredje upplagan av ”Sepsis på akuten och IVA” baseras delvis på SK-kursen med samma namn. Bokens innehall har dock utökats for att kunna ge praktiska anvisningar for diagnostik och terapi vid sepsis hos barn och vuxna med olika infektionsfokus. Sepsisboken ger också en inblick i vilka mekanismer som gör att sepsis snabbt kan bli ett livshotande tillstånd och vilka åtgärder som det ar mest bråttom med under de första timmarna av septisk chock. Kort tid mellan upptäckt av septisk chock och ratt insatt behandling sparar både organfunktion och liv. Modern intensivvård med monitorering av vätsketillförsel, vasokativa droger, respirator, dialys etc ar liksom ratt antibiotika i ratt dos en förutsättning for att kunna radda en patient med septisk chock. For att kunna ge ratt antibiotika kravs kunskap om vilka bakterier som ar vanligast vid olika typer av infektioner och deras antibiotikakänslighet. Ett kapitel i denna bok agnas därför at resistensläget i blododlingar från svenska patienter.

    Patienter som har nedsatt njurfunktion löper större risk for felaktig dosering av antimikrobiella läkemedel och behandlingsmisslyckande varför boken innehåller flera tabeller med doseringsanvisningar vid nedsatt njurfunktion och dialys. Ett kapitel agnas at handläggning av allvarliga bakteriella infektioner hos barn eftersom barn reagerar något annorlunda an vuxna vid sepsis, S. aureus ar vanligare och barn har en delvis annorlunda behandlingsalgoritm. Barn med immunsuppression berörs också och det ar ett kapitel om allvarliga infektioner hos vuxna patienter med neutropeni. Ett separat kapitel agnas at de relativt ovanliga men livshotande hud och mjukdelsinfektionerna som kräver snabb kirurgisk intervention och bra samarbete mellan kirurger, intensivvårdsläkare och infektionsläkare. Svampsepsis har okat på IVA pga alltmer avancerad intensivvård och agnas ett eget kapitel da svampsepsis ofta ar svårdiagnosticerat. Empirisk behandling med nya antimykotika har därför blivit allt vanligare och det ar viktigt att ha kännedom om vilka preparat som har bast effekt och ar kostnadseffektiva. Samhällsförvärvade och sjukhusförvärvade intensivvårdskrävande pneumonier har båda hög dödlighet och en sammanfattning av behandlingsalgoritmer ar inkluderade i boken. Intensivvård innebar risk for sjukhusförvärvade infektioner och riktlinjer for hur man skall undvika, diagnosticera och behandla blodkateterassocierade infektioner agnas ett kapitel. For en optimal handläggning av septiska infektioner ar det viktigt att ta reda på förekomst av immunsuppression och komorbiditet, göra en korrekt bedömning av svårighetsgrad, stalla ratt preliminär diagnos inklusive infektionsfokus, sannolik etiologi och risk for antibiotikaresistens. Boken innehåller flera sammanfattningar och checklistor for snabb korrekt empirisk antimikrobiell behandling av intensivvårdskrävande infektioner både på akuten och IVA.

    Vi hoppas att boken skall bidra till att förbättra varden av patienter med sepsis och andra svara infektioner. Stort tack till alla medförfattare som bidragit med sin expertis och till Region Östergötland som bidragit ekonomiskt och möjliggjort utgivning av denna bok.

    Linköping i Januari 2017

    Hakan Hanberger

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  • 224.
    Hanberger, Håkan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Infectious Diseases.
    Sepsis på akuten & IVA: diagnostik och antibiotikaterapi2013Collection (editor) (Other academic)
    Abstract [sv]

    Sepsis på akuten och IVA baseras på SK-kursen med samma namn. Vi har i andra upplagan flera nya kapitel och hoppas att boken skall bidra till att förbättra vården av patienter med sepsis och andra svåra infektioner.

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  • 225.
    Hanberger, Håkan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Infectious Diseases.
    Antonelli, Massimo
    Policlinico University of A. Gemelli, Rome, Italy.
    Holmbom, Martin
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences.
    Lipman, Jeffrey
    University of Queensland, Herston, Australia.
    Pickkers, Peter
    Radboud University Medical Centre, Nijmegen, The Netherlands.
    Leone, Marc
    Aix Marseille University, France.
    Rello, Jordi
    University Autonoma of Barcelona, Spain.
    Sakr, Yasser
    Friedrich-Schiller University, Jena, Germany.
    Walther, Sten
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Vanhems, Philippe
    University of Lyon 1, France.
    Vincent, Jean-Louis
    University Libre Bruxelles, Belgium.
    Infections, antibiotic treatment and mortality in patients admitted to ICUs in countries considered to have high levels of antibiotic resistance compared to those with low levels2014In: BMC Infectious Diseases, ISSN 1471-2334, E-ISSN 1471-2334, Vol. 14, no 513Article in journal (Refereed)
    Abstract [en]

    Background: Antimicrobial resistance is an increasing concern in ICUs worldwide. Infection with an antibiotic resistant (ABR) strain of an organism is associated with greater mortality than infection with the non-resistant strain, but there are few data assessing whether being admitted to an intensive care unit (ICU) with high levels of antimicrobial resistance is associated with a worse outcome than being admitted to an ICU with low rates of resistance. The aim of this study was, therefore, to compare the characteristics of infections and antibiotic treatments and patient outcomes in patients admitted to ICUs in countries considered as having high levels of antibiotic resistance and those admitted to ICUs in countries considered as having low levels of antibiotic resistance. Methods: Data from the large, international EPIC II one-day point prevalence study on infections in patients hospitalized in ICUs were used. For the current study, we compared the data obtained from patients from two groups of countries: countries with reported MRSA rates of greater than= 25% (highABR: Greece, Israel, Italy, Malta, Portugal, Spain, and Turkey) and countries with MRSA rates of less than 5% (lowABR: Denmark, Finland, Netherlands, Norway, and Sweden). Results: On the study day, 1187/2204 (53.9%) patients in the HighABR ICUs were infected and 255/558 (45.7%) in the LowABR ICUs (P less than 0.01). Patients in the HighABR ICUs were more severely ill than those in the LowABR ICUs, as reflected by a higher SAPS II score (35.6 vs 32.7, P less than 0.05) and had longer median ICU (12 days vs 5 days) and hospital (24 days vs 16 days) lengths of stay. They also had higher crude ICU (20.0% vs 15.4%) and hospital (27.0% vs 21.5%) mortality rates (both P less than 0.05). However, after multivariable adjustment and matched pair analysis there were no differences in ICU or hospital mortality rates between High or LowABR ICU patients overall or among those with infections. Conclusions: Being hospitalized in an ICU in a region with high levels of antimicrobial resistance is not associated per se with a worse outcome.

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  • 226.
    Hanberger, Håkan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Infectious Diseases in Östergötland.
    Fredrikson, Mats
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Ternhag, Anders
    Swedish Institute Communicable Disease Control, Sweden .
    Giske, Christian G.
    Karolinska University Hospital, Sweden .
    Letter: Rational use of aminoglycosides - author response2013In: Scandinavian Journal of Infectious Diseases, ISSN 0036-5548, E-ISSN 1651-1980, Vol. 45, no 8, p. 655-656Article in journal (Other academic)
    Abstract [en]

    n/a

  • 227.
    Hanberger, Håkan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Nilsson, Lennart E
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Maller, Rolf
    Linköping University, Department of Molecular and Clinical Medicine, Infectious Diseases. Linköping University, Faculty of Health Sciences.
    Isaksson, Barbro
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Pharmacodynamics of daptomycin and vancomycin on Enterococcus faecalis and Staphylococcus aureus demonstrated by studies of initial killing and postantibiotic effect and influence of Ca2+ and albumin on these drugs.1991In: Antimicrobial Agents and Chemotherapy, ISSN 0066-4804, E-ISSN 1098-6596, Vol. 35, no 9, p. 1710-1716Article in journal (Refereed)
    Abstract [en]

    The pharmacodynamics of daptomycin and vancomycin on Enterococcus faecalis ATCC 29212 and Staphylococcus aureus ATCC 25923 were investigated by studying the postantibiotic effect (PAE) and initial killing. The influence of Ca2+ and albumin on these drugs was also evaluated. The PAE was studied by use of bioluminescence assay of bacterial ATP. Daptomycin at clinically achievable concentrations produced a dose-dependent PAE on E. faecalis (0.6 to 6.7 h) and S. aureus (1.0 to 6.3 h). The long PAE of daptomycin was seen simultaneously with a potent dose-dependent initial killing assayed by viable count determination. The initial change in bacterial ATP was not as extensive as the decrease in viability. Vancomycin at corresponding concentrations produced shorter PAEs on E. faecalis (0.5 to 1.0 h) and S. aureus (1.3 to 1.8 h). This coincides with a weak non-dose-dependent initial change in viability and intracellular ATP. The MICs of vancomycin were not influenced by different Ca2+ concentrations or by the addition of albumin to the broth. The MICs of daptomycin for both strains were lowered, and the PAEs were prolonged with increasing concentrations of Ca2+ in the broth. The PAE of daptomycin was Ca2+ dependent to the same extent as the MIC was. In the presence of physiological concentrations of albumin and free Ca2+, the PAEs of daptomycin on both strains were reduced and the MICs were increased in comparison with the results obtained in pure Mueller-Hinton broth with approximately the same free Ca2+ concentration. This decrease in daptomycin activity was considered to be due to the albumin binding of daptomycin. Despite the albumin binding of daptomycin, the PAE produced on E. faecalis and S. aureus in the presence of a physiological free Ca2+ concentration was still over 6 h at clinically achievable concentrations.

  • 228.
    Hanberger, Håkan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Infectious Diseases.
    Skoog, Gunilla
    Public Health Agency Sweden, Sweden .
    Ternhag, Anders
    Public Health Agency Sweden, Sweden Karolinska Institute, Sweden .
    Giske, Christian G.
    Karolinska University Hospital, Sweden .
    Antibiotic consumption and antibiotic stewardship in Swedish hospitals2014In: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 119, no 2, p. 154-161Article, review/survey (Refereed)
    Abstract [en]

    Background. The aim of this paper was to describe and analyze the effect of antibiotic policy changes on antibiotic consumption in Swedish hospitals and to review antibiotic stewardship in Swedish hospitals. Results. The main findings were: 1) Antibiotic consumption has significantly increased in Swedish hospitals over the last decade. The consumption of cephalosporins has decreased, whereas that of most other drugs including piperacillin-tazobactam, carbapenems, and penicillinase-sensitive and -resistant penicillins has increased and replaced cephalosporins. 2) Invasive infections caused by ESBL-producing Escherichia coli and Klebsiella pneumoniae have increased, but the proportion of pathogens resistant to third-generation cephalosporins causing invasive infections is still very low in a European and international perspective. Furthermore, the following gaps in knowledge were identified: 1) lack of national, regional, and local data on the incidence of antibiotic resistance among bacteria causing hospital-acquired infections e. g. bloodstream infections and hospital-acquired pneumonia-data on which standard treatment guidelines should be based; 2) lack of data on the incidence of Clostridium difficile infections and the effect of change of antibiotic policies on the incidence of C. difficile infections and infections caused by antibiotic-resistant pathogens; and 3) lack of prospective surveillance programs regarding appropriate antibiotic treatment, including selection of optimal antimicrobial drug regimens, dosage, duration of therapy, and adverse ecological effects such as increases in C. difficile infections and emergence of antibiotic-resistant pathogens. Conclusions. Evidence-based actions to improve antibiotic use and to slow down the problem of antibiotic resistance need to be strengthened. The effect of such actions should be analyzed, and standard treatment guidelines should be continuously updated at national, regional, and local levels.

  • 229.
    Hanna, Nada
    et al.
    Karolinska Inst, Sweden.
    Sun, Pan
    Shandong Univ, Peoples R China.
    Sun, Qiang
    Shandong Univ, Peoples R China.
    Li, Xuewen
    Shandong Univ, Peoples R China.
    Yang, Xiwei
    Shandong Univ, Peoples R China.
    Ji, Xiang
    Shandong Univ, Peoples R China.
    Zou, Huiyun
    Shandong Univ, Peoples R China.
    Ottoson, Jakob
    Natl Food Agcy, Sweden.
    Nilsson, Lennart E
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Berglund, Björn
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Dyar, Oliver James
    Karolinska Inst, Sweden.
    Tamhankar, Ashok J.
    Karolinska Inst, Sweden.
    Lundborg, Cecilia Stalsby
    Karolinska Inst, Sweden.
    Presence of antibiotic residues in various environmental compartments of Shandong province in eastern China: Its potential for resistance development and ecological and human risk2018In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 114, p. 131-142Article in journal (Refereed)
    Abstract [en]

    Objectives: To investigate the occurrence of antibiotic residues in different types of environmental samples including water samples in rural Shandong province, China. Further, to characterize the potential ecological risk for development of antibiotic resistance in the environment, and the potential direct human health risk of exposure to antibiotics via drinking water and vegetables. Methods: Environmental samples (n = 214) (river water, waste water, drinking water, sediments, manure, soil and edible parts of vegetables) were collected in twelve villages in Shandong province in eastern China. High performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was used to determine the concentration of antibiotic residues. The ratio of the measured environmental concentrations (MEC) to the predicted no-effect concentrations (PNEC) was used to evaluate the ecological risk (risk quotient, RQ) for development of antibiotic resistance. The potential risks to human health through exposure to antibiotics in drinking water were assessed by comparing measured environmental concentrations (MEC) and predicted no-effect concentration in drinking water (PNECDW), and in vegetables by comparing estimated daily intake (EDI) to ADI. Results: Sulfapyridine, sulfamethoxazole, ciprofloxacin, enrofloxacin, levofloxacin, norfloxacin, chloramphenicol, florfenicol, doxycycline, and metronidazole were detected at concentrations ranging between 0.3 and 3.9 ng/L in river water, 1.3 and 12.5 ng/L in waste water, 0.5 and 21.4 ng/L in drinking water, 0.31 and 1.21 mu g/kg in river sediment, 0.82 and 1.91 mu g/kg in pig manure, 0.1 and 11.68 mu g/kg in outlet sediment, 0.5 and 2.5 mu g/kg in soil, and 6.3 and 27.2 mu g/kg in vegetables. The RQs for resistance development were amp;gt; 1 for enrofloxacin, levofloxacin, and ranged between 0.1 and 1 for ciprofloxacin. MECs/PNECDW ratios were amp;lt; 1 from exposure to antibiotics through drinking water for both adults and children. EDI/ADI ratios were amp;lt; 0.1 from exposure to antibiotics by vegetable consumption. Conclusions: Antibiotic pollutants were ubiquitous in various environmental compartments of Shandong province of China. Risk estimates indicated a potential for the measured levels of enrofloxacin, levofloxacin and ciprofloxacin in waste water to pose an ecological risk for resistance selection, and further studies are needed to validate this finding. The investigated antibiotics did not appear to pose an appreciable direct human health risk from environmental exposure through drinking water or vegetables consumption. However, they might still pose a risk for resistance development.

  • 230.
    Harris, L. F.
    et al.
    Dublin Institute Technology, Ireland.
    Rainey, P.
    Queens University of Belfast, North Ireland.
    Lindahl, Tomas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Killard, A. J.
    University of West England, England.
    A fully integrated microfluidic device for point of care monitoring of antithrombotics2016In: Analytical Methods, ISSN 1759-9660, E-ISSN 1759-9679, Vol. 8, no 35, p. 6500-6505Article in journal (Refereed)
    Abstract [en]

    The simplicity and efficiency of point of care diagnostics have revolutionised patient care. Current methods for measuring hypercoagulability often require trained technicians, large blood volumes, and result in long turnaround times. Standard testing for hypercoagulable disorders is performed in the central laboratory using automated coagulation analysers. However the trend is moving towards the development and implementation of point of care testing, as a result of the ever increasing number of patients on antithrombotic therapy. We present a novel microfluidic device and assay for monitoring the effect of two anticoagulants, unfractionated heparin (UFH) and low molecular weight heparin (LMWH). The assay is based on the anti-Xa assay principle but uses fluorescence detection. Our device is a disposable laminate microfluidic strip, fabricated from the cyclic polyolefin (COP), Zeonor (R), which is extremely suitable for application to fluorescent device platforms. We present data on the execution of the anti-Xa assay in this microfluidic format, demonstrating that the assay can be used to measure both UFH and LMWH in human plasma samples from 0 to 1 U mL(-1), with a rapid result obtained within 30-60 seconds.

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  • 231.
    Hedenstierna, M
    et al.
    Karolinska Universitetssjukhuset Huddinge, Stockholm.
    Weiland, O
    Karolinska Universitetssjukhuset Huddinge, Stockholm.
    Brass, A
    Karolinska Institutet, Stockholm .
    Bankwitz, D
    Twincore Centre for Experimental and Clinical Infection Research, Hannover, Germany.
    Behrendt, P
    Twincore Centre for Experimental and Clinical Infection Research, Hannover, Germany.
    Uhnoo, I
    Akademiska Universitetssjukhuset, Uppsala .
    Aleman, S
    Karolinska Universitetssjukhuset Huddinge och Solna, Stockholm.
    Cardell, Kristina
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Infectious Diseases.
    Frydén, Aril
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Infectious Diseases.
    Norkrans, G
    Sahlgrenska Universitetssjukhuset, Göteborg .
    Eilard, A
    Sahlgrenska Universitetssjukhuset, Göteborg .
    Glaumann, H
    Karolinska Universitetssjukhuset Huddinge .
    Pietschmann, T
    Twincore Centre for Experimental and Clinical Infection Research, Hannover, Germany.
    Sällberg, M
    Karolinska Institutet, Stockholm .
    Brenndörfer, E D
    Karolinska Institutet, Stockholm.
    Long-term follow-up of successful hepatitis C virus therapy: waning immune responses and disappearance of liver disease are consistent with cure.2015In: Alimentary Pharmacology and Therapeutics, ISSN 0269-2813, E-ISSN 1365-2036, Vol. 41, no 6, p. 532-543Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: A sustained viral response (SVR) after interferon-based therapy of chronic hepatitis C virus (HCV) infection is regarded to represent a cure. Previous studies have used different markers to clarify whether an SVR truly represents a cure, but no study has combined a clinical work-up with highly sensitive HCV RNA detection, and the determination of immune responses.

    AIM: To determine clinical, histological, virological and immunological markers 5-20 years after SVR.

    METHODS: In 54 patients, liver biochemistry, histology and elastography were evaluated. Liver biopsies, plasma and peripheral blood mononuclear cells (PBMCs) were tested for minute amounts of HCV RNA. HCV-specific T-cell responses were monitored by ELISpot and pentamer staining, and humoral responses by measuring HCV nonstructural (NS)3-specific antibodies and virus neutralisation.

    RESULTS: Liver disease regressed significantly in all patients, and 51 were HCV RNA-negative in all tissues tested. There was an inverse association between liver disease, HCV-specific T-cell responses and HCV antibody levels with time from SVR, supporting that the virus had been cleared. The three patients, who all lacked signs of liver disease, had HCV RNA in PBMCs 5-9 years after SVR. All three had HCV-specific T cells and NS3 antibodies, but no cross-neutralising antibodies.

    CONCLUSIONS: Our combined data confirm that a SVR corresponds to a long-term clinical cure. The waning immune responses support the disappearance of the antigenic stimulus. Transient HCV RNA traces may be detected in some patients up to 9 years after SVR, but no marker associates this with an increased risk for liver disease.

  • 232.
    Hedin, Christina
    et al.
    Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Sjödahl, Rune
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Surgery in Linköping.
    Aldman, Åke
    Västerviks sjukhus, Västervik, Sweden.
    Davidson, Thomas
    Linköping University, Department of Medical and Health Sciences, Division of Health Care Analysis. Linköping University, Faculty of Medicine and Health Sciences.
    Kammerlind, Ann-Sofie
    Region Jönköpings län, Jönköping, Sweden.
    Nodbrant, Per
    Onkologiska kliniken, Länssjukhuset Ryhov, Jönköping, Sweden.
    Agrup, Måns
    Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Oncology. Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Intraoperativ strålbehandling vid primar operation for bröstcancer: TARGIT-A-studien ej konklusiv2018In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 115, article id EWFFArticle, review/survey (Refereed)
    Abstract [sv]

    The TARGIT-A (TARGeted Intraoperative radioTherapy) multicentre study of early breast cancer compared intraoperative radiotherapy with external radiotherapy. While the intraoperative radiotherapy was standardised, the external postoperative comparison treatment followed established routines in the participating treatment centres resulting in substantial variations in dosages and treatment durations. The uncertainties in the interpretation of the study results created by the design of the TARGIT-A study constitute substantial obstacles to the possible introduction of intraoperative radiotherapy for early breast cancer.

  • 233.
    Hedin Skogman, Barbro
    et al.
    Center for Clinical Research, Falun, Sweden.
    Forsberg, Pia
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Infectious Diseases.
    Vene, Sirkka
    Smittskyddsinstutet .
    Åkerlind, Britt
    Östergötlands Läns Landsting, Center for Health and Developmental Care, Department of Infection Control.
    Are There Undiagnosed TBE-, Herpes- or Enteroviral Infections among Children Being Evaluated for Lyme Neuroborreliosis?2014In: Open Journal of Clinical Diagnostics, ISSN 2162-5816, E-ISSN 2162-5824, Vol. 4, no 3, p. 123-129Article in journal (Refereed)
    Abstract [en]

    Lyme neuroborreliosis (LNB) in children is a challenging diagnosis based on clinical manifestations and laboratory findings. The aim of this study was to investigate whether herpes simplex virus (HSV) 1 or 2, varicella zoster virus (VZV), enterovirus or tick-borne encephalitis virus (TBEV) could be identified in cerebrospinal fluid (CSF) or serum from children being evaluated for LNB, in order to elucidate whether such infectious diseases may be missed by the clinician. Methods: Ninety-nine pediatric patients (n = 99) were retrospectively included from a previous study on LNB in southeast of Sweden. They had been diagnosed as “Possible LNB” or “Not determined” due to negative Borrelia antibody index in CSF. Routine polymerase chain reaction (PCR) methods were used for detection of herpes viral RNA or enteroviral DNA in CSF. An ELISA assay was used for detection of anti-TBEV antibodies (IgM and IgG) in serum. Results: One patient showed elevated anti-TBEV IgM and IgG antibodies in serum, indicating a current TBE infection. No positive PCR reactions for HSV 1 or 2, VZV or enterovirus were detected in CSF from any of the patients. In conclusion, our results suggest that undiagnosed herpes- or enteroviral infections are unlikely to explain CNS symptoms in children being evaluated for LNB, whereas missed TBE infections may occur. TBEV serology should be included when evaluating children for LNB in TBE endemic areas.

  • 234.
    Heenkenda, Menikae K.
    et al.
    Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry. Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine.
    Lindahl, Tomas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Osman, Abdimajid
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Frequency of PAR4 Ala120Thr variant associated with platelet reactivity significantly varies across sub-Saharan African populations2018In: Blood, ISSN 0006-4971, E-ISSN 1528-0020, Vol. 132, no 19, p. 2103-2106Article in journal (Other academic)
    Abstract [en]

    n/a

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  • 235.
    Henningsson, A. J.
    et al.
    Regional Jönköping County, Sweden.
    Nilsson Bowers, A.
    Regional Jönköping County, Sweden.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Quttineh, M.
    Regional Jonköping County, Sweden.
    Matussek, A.
    Regional Jonköping County, Sweden; Karolinska University Hospital, Sweden; Karolinska Institute, Sweden.
    Haglund, S.
    Regional Jonköping County, Sweden.
    Rapid diagnosis of acute norovirus-associated gastroenteritis: evaluation of the Xpert Norovirus assay and its implementation as a 24/7 service in three hospitals in Jonkoping County, Sweden2017In: European Journal of Clinical Microbiology and Infectious Diseases, ISSN 0934-9723, E-ISSN 1435-4373, Vol. 36, no 10, p. 1867-1871Article in journal (Refereed)
    Abstract [en]

    Noroviruses are a leading cause of epidemic and sporadic cases of acute gastroenteritis worldwide. The rapid diagnosis of norovirus infection is important for prompt infection control measures and may reduce the need for additional diagnostic testing. Here we evaluated the performance of the rapid Xpert Norovirus assay, and assessed the turn-around time (TAT) before and after the implementation of the analysis as a 24/7 service at all the three hospitals in Jonkoping County, Sweden. We describe the implementation process which was performed in two steps during 2014. A total number of 276 clinical samples (stool and vomitus) from patients with symptoms of acute gastroenteritis were included in 2014-2015. The samples were analysed with the Xpert Norovirus assay and the already existing routine method: an in-house reverse transcription real-time PCR. Samples showing discrepant results with the two assays were further analysed by a third PCR method. The Xpert Norovirus assay performed well with a sensitivity of 100% and a specificity of 93% compared to the gold standard (defined as the result obtained by at least two of the three PCR methods). The median TAT decreased from 22 hours in 2013 to 2.4 hours in 2015 (p amp;lt; 0.001). We conclude that the performance of the Xpert Norovirus assay was excellent, and that the implementation of the analysis as a 24/7 service at all three hospitals in the county has greatly reduced the time to diagnosis which is beneficial for both patients and healthcare providers.

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  • 236.
    Henningsson, Anna
    et al.
    Regional Jonköping County, Sweden.
    Gyllemark, Paula
    Regional Jonköping County, Sweden.
    Lager, Malin
    Regional Jonköping County, Sweden.
    Hedin Skogman, Barbro
    Centre Clin Research Dalarna, Sweden.
    Tjernberg, Ivar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Kalmar County Council, Sweden.
    Evaluation of two assays for CXCL13 analysis in cerebrospinal fluid for laboratory diagnosis of Lyme neuroborreliosis2016In: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS), ISSN 0903-4641, E-ISSN 1600-0463, Vol. 124, no 11, p. 985-990Article in journal (Refereed)
    Abstract [en]

    We evaluated the diagnostic performance of two assays, one bead-based assay and one enzyme-linked immunosorbent assay (ELISA), for the determination of CXCL13 levels in cerebrospinal fluid (CSF) from patients with suspected Lyme neuroborreliosis (LNB). Patients investigated for LNB were retrospectively included (n = 132): 35 with definite LNB, 8 with possible LNB with CSF pleocytosis but normal antibody index (AI), 6 with possible LNB with elevated AI but no CSF pleocytosis and 83 non-LNB patients. CSF samples had been drawn before antibiotic treatment and were analysed for CXCL13 by Quantikine ELISA (Ramp;D Systems) and recomBead (Mikrogen). Receiver operating characteristic analyses based on the definite LNB and non-LNB groups revealed a best performance cut-off of 56 pg/mL for Quantikine and 158 pg/mL for recomBead (sensitivity and specificity 100% for both assays). When applying these cut-off levels on the study groups, the two assays performed equally well regarding sensitivity and specificity. In the group of patients with pleocytosis but negative AI, the majority of whom were children with short symptom duration, the CXCL13 analysis supported the LNB diagnosis in half of the cases. We consider CSF-CXCL13 analysis a useful diagnostic tool, in addition to Borrelia-specific AI, in laboratory diagnostics of LNB.

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  • 237.
    Henningsson, Anna
    et al.
    Regional Jonköping County, Sweden.
    Lindqvist, Richard
    Umeå University, Sweden.
    Norberg, Peter
    University of Gothenburg, Sweden.
    Lindblom, Pontus
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Roth, Anette
    University of Gothenburg, Sweden.
    Forsberg, Pia
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Infectious Diseases.
    Bergstrom, Tomas
    University of Gothenburg, Sweden.
    Overby, Anna K.
    Umeå University, Sweden.
    Lindgren, Per-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Regional Jonköping County, Sweden.
    Human Tick-Borne Encephalitis and Characterization of Virus from Biting Tick2016In: Emerging Infectious Diseases, ISSN 1080-6040, E-ISSN 1080-6059, Vol. 22, no 8, p. 1485-1487Article in journal (Refereed)
    Abstract [en]

    We report a case of human tick-borne encephalitis (TBE) in which the TBE virus was isolated from the biting tick. Viral growth and sequence were characterized and compared with those of a reference strain. Virus isolation from ticks from patients with TBE may offer a new approach for studies of epidemiology and pathogenicity.

  • 238.
    Henningsson, Anna
    et al.
    Ryhov County Hospital, Jönköping.
    Wilhelmsson, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Gyllemark, Paula
    Ryhov County Hospital, Jönköping.
    Kozak Ljunggren, Monika
    Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology.
    Matussek, Andreas
    Ryhov County Hospital, Jönköping.
    Nyman, Dag
    Ryhov County Hospital, Jönköping.
    Ekerfelt, Christina
    Bimelix Biomedical Laboratory, Mariehamn, Åland, Finland .
    Lindgren, Per-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Ryhov County Hospital, Jönköping.
    Forsberg, Pia
    Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Infectious Diseases. Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine.
    Low risk of seroconversion or clinical disease in humans after a bite by an Anaplasma phagocytophilum-infected tick2015In: Ticks and Tick-borne Diseases, ISSN 1877-959X, E-ISSN 1877-9603, Vol. 6, no 6, p. 787-792Article in journal (Refereed)
    Abstract [en]

    The risk of contracting human granulocytic anaplasmosis (HGA) after a tick bite is mainly unknown. In this study we investigated the clinical and serological response in 30 humans bitten by ticks positive for Anaplasma phagocytophilum (Group A), 30 humans bitten by Borrelia burgdorferi sensu lato (s.l.)-positive ticks (Group B), and 30 humans bitten by ticks negative for both A. phagocytophilum and B. burgdorferi s.l. (Group C). Ticks, blood samples and questionnaires were collected from tick-bitten humans at 34 primary healthcare centres in Sweden and in the Åland Islands, Finland, at the time of the tick bite and after three months. A total of 2553 ticks detached from humans in 2007-2009 were analyzed by polymerase chain reaction, and 31 (1.2%) were positive for A. phagocytophilum, 556 (21.8%) were positive for B. burgdorferi s.l., and eight (0.3%) were co-infected by A. phagocytophilum and B. burgdorferi s.l. The overall prevalence of Anaplasma IgG antibodies in the included participants (n=90) was 17%, and there was no significant difference between the groups A-C. Only one of the participants (in Group C) showed a four-fold increase of IgG antibodies against A. phagocytophilum at the three-month follow-up, but reported no symptoms. The frequency of reported symptoms did not differ between groups A-C, and was unrelated to the findings of A. phagocytophilum and B. burgdorferi s.l. in the detached ticks. We conclude that the risk for HGA or asymptomatic seroconversion after a tick bite in Sweden or in the Åland Islands is low, even if the tick is infected by A. phagocytophilum.

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  • 239.
    Heyckendorf, Jan
    et al.
    Res Ctr Borstel, Germany; German Ctr Infect Res DZIF, Germany; Univ Lubeck, Germany.
    Andres, Soenke
    Res Ctr Borstel, Germany.
    Koser, Claudio U.
    Univ Cambridge, England.
    Olaru, Ioana D.
    Res Ctr Borstel, Germany; German Ctr Infect Res DZIF, Germany.
    Schön, Thomas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Kalmar Cty Hosp, Sweden.
    Sturegard, Erik
    Lund Univ, Sweden.
    Beckert, Patrick
    German Ctr Infect Res DZIF, Germany; Karolinska Inst, Sweden.
    Schleusener, Viola
    Karolinska Inst, Sweden.
    Kohl, Thomas A.
    German Ctr Infect Res DZIF, Germany; Karolinska Inst, Sweden.
    Hillemann, Doris
    Res Ctr Borstel, Germany.
    Moradigaravand, Danesh
    Wellcome Trust Sanger Inst, England.
    Parkhill, Julian
    Wellcome Trust Sanger Inst, England.
    Peacock, Sharon J.
    Wellcome Trust Sanger Inst, England; London Sch Hyg and Trop Med, England.
    Niemann, Stefan
    German Ctr Infect Res DZIF, Germany; Univ Cambridge, England; Res Ctr Borstel, Germany.
    Lange, Christoph
    Res Ctr Borstel, Germany; German Ctr Infect Res DZIF, Germany; Univ Lubeck, Germany; Karolinska Inst, Sweden; Univ Namibia, Namibia.
    Merker, Matthias
    German Ctr Infect Res DZIF, Germany; Res Ctr Borstel, Germany.
    What Is Resistance? Impact of Phenotypic versus Molecular Drug Resistance Testing on Therapy for Multi-and Extensively Drug-Resistant Tuberculosis2018In: Antimicrobial Agents and Chemotherapy, ISSN 0066-4804, E-ISSN 1098-6596, Vol. 62, no 2, article id e01550-17Article in journal (Refereed)
    Abstract [en]

    Rapid and accurate drug susceptibility testing (DST) is essential for the treatment of multi-and extensively drug-resistant tuberculosis (M/XDR-TB). We compared the utility of genotypic DST assays with phenotypic DST (pDST) using Bactec 960 MGIT or Lowenstein-Jensen to construct M/XDR-TB treatment regimens for a cohort of 25 consecutive M/XDR-TB patients and 15 possible anti-TB drugs. Genotypic DST results from Cepheid GeneXpert MTB/RIF (Xpert) and line probe assays (LPAs; Hain GenoType MTBDRplus 2.0 and MTBDRsl 2.0) and whole-genome sequencing (WGS) were translated into individual algorithmderived treatment regimens for each patient. We further analyzed if discrepancies between the various methods were due to flaws in the genotypic or phenotypic test using MIC results. Compared with pDST, the average agreement in the number of drugs prescribed in genotypic regimens ranged from just 49% (95% confidence interval [ CI], 39 to 59%) for Xpert and 63% (95% CI, 56 to 70%) for LPAs to 93% (95% CI, 88 to 98%) for WGS. Only the WGS regimens did not contain any drugs to which pDST showed resistance. Importantly, MIC testing revealed that pDST likely underestimated the true rate of resistance for key drugs (rifampin, levofloxacin, moxifloxacin, and kanamycin) because critical concentrations (CCs) were too high. WGS can be used to rule in resistance even in M/XDR strains with complex resistance patterns, but pDST for some drugs is still needed to confirm susceptibility and construct the final regimens. Some CCs for pDST need to be reexamined to avoid systematic false-susceptible results in low-level resistant isolates.

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  • 240.
    Hillarp, A.
    et al.
    University and Regional Laboratories Region Skåne, Malmö, Sweden.
    Gustafsson, Kerstin
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Faxälv, Lars
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry.
    Strandberg, K.
    University and Regional Laboratories Region Skåne, Malmö, Sweden.
    Baghaei, F.
    Sahlgrenska University Hospital, Sweden; University of Gothenburg, Sweden.
    Fagerberg Blixter, I.
    Sahlgrenska University Hospital, Sweden; University of Gothenburg, Sweden.
    Berndtsson, M.
    Karolinska University Hospital, Stockholm, Sweden.
    Lindahl, Tomas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry.
    Effects of the oral, direct factor Xa inhibitor apixaban on routine coagulation assays and anti-FXa assays2014In: Journal of Thrombosis and Haemostasis, ISSN 1538-7933, E-ISSN 1538-7836, Vol. 12, no 9, p. 1545-1553Article in journal (Refereed)
    Abstract [en]

    INTRODUCTION:

    Apixaban is an oral direct factor Xa inhibitor developed for the prophylaxis and treatment of thromboembolic disorders. Laboratory monitoring is not necessary, but the effects on common coagulation reagents and assays constitute clinically valuable information.

    OBJECTIVES:

    To investigate the effects of apixaban on commonly used coagulation methods, and to evaluate anti-FXa assays for specific determination of the drug concentration.

    MATERIALS AND METHODS:

    Apixaban was added to plasma from healthy subjects in the concentration range 0-1000 μg L(-1) , and analyses were performed with different reagents for activated partial thromboplastin time (APTT), prothrombin time (PT), antithrombin, protein C, and protein S. A lupus anticoagulant assay and an APTT assay with varying phospholipid concentrations were used to study the phospholipid dependence.

    RESULTS:

    In general, apixaban showed fewer effects in vitro than have been shown for rivaroxaban, another direct FXa inhibitor. The concentration needed to double the APTT varied between 2200 and 4700 μg L(-1) , and the concentration needed to double the PT varied between 700 and 3900 μg L(-1) . The effects on antithrombin, protein C and protein S assays were dependent on the type of reagent. Apixaban did not cause false-positive lupus anticoagulant results. Chromogenic anti-FXa assays showed linear dose-response curves with apixaban.

    CONCLUSIONS:

    Therapeutic concentrations of apixaban variably affect different assay groups, and even different reagents within an assay group. The effects were much smaller than with rivaroxaban. The use of APTT and/or PT assays to screen the anticoagulant activity of apixaban cannot be recommended. A chromogenic anti-FXa assay can be used for reliable measurements of apixaban concentration.

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  • 241.
    Hillarp, Andreas
    et al.
    Halland Cty Hosp, Sweden.
    Strandberg, Karin
    Univ and Reg Labs Reg Skane, Sweden.
    Baghaei, Fariba
    Sahlgrens Univ Hosp, Sweden.
    Blixter, Inger Fagerberg
    Univ Gothenburg, Sweden.
    Gustafsson, Kerstin
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Lindahl, Tomas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Effects of the oral, direct factor Xa inhibitor edoxaban on routine coagulation assays, lupus anticoagulant and anti-Xa assays2018In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 78, no 7-8, p. 575-583Article in journal (Refereed)
    Abstract [en]

    Edoxaban is an oral direct factor Xa inhibitor for prophylaxis and treatment of thromboembolic disorders. The effects on common coagulation assays are clinically valuable information and in certain clinical situations a quick assessment of the anticoagulant is wanted. Our aim was to investigate the effect of edoxaban on routine coagulation methods and evaluate anti-Xa assays, commonly used for other direct factor Xa inhibitors, for estimation of the drug concentration. Edoxaban was spiked to plasma samples from healthy subjects in the concentration range 0-742 mu g/L and analyzed using different reagents for activated partial thromboplastin time (APTT) and prothrombin time (PT). Assays for antithrombin, activated protein C resistance, lupus anticoagulant (LA) and chromogenic anti-Xa assays were also included. Edoxaban displayed similar effects in vitro to other oral direct Xa inhibitors. The concentration needed to double the coagulation time varied between assays and reagents; 539-758 mu g/L for the APTT and between 329 and 2505 mu g/L for the PT. Edoxaban gave false high antithrombin activities in assays based on Xa-inhibition. Two integrated assays for LA, both based on activation with dilute Russells viper venom, displayed different results. Chromogenic anti-Xa assays displayed linear dose-response curves with edoxaban up to approximately 500 mu g/L. In conclusion, therapeutic concentrations of edoxaban variably affect different coagulation assays, and even different reagents within an assay group. In comparison with other oral Xa-inhibitors, the in vitro effects of edoxaban were more similar to rivaroxaban than apixaban. For measurement of edoxaban concentration in plasma, it is possible to use the chromogenic anti-Xa assays.

  • 242.
    Hinkula, Jorma
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Institute, Sweden.
    Devignot, Stephanie
    Philipps University of Marburg, Germany; Justus Liebig University, Germany.
    Åkerström, Sara
    National Vet Institute, Sweden.
    Karlberg, Helen
    Folkhälsomyndigheten, Sweden.
    Wattrang, Eva
    National Vet Institute, Sweden.
    Bereczky, Sandor
    Folkhalsomyndigheten, Sweden.
    Mousavi-Jazi, Mehrdad
    Folkhalsomyndigheten, Sweden.
    Risinger, Christian
    Department of Chemistry, University of Copenhagen, Frederiksberg, Denmark .
    Lindegren, Gunnel
    Folkhalsomyndigheten, Sweden.
    Vernersson, Caroline
    National Vet Institute, Sweden.
    Paweska, Janusz
    National Institute Communicable Disease, South Africa.
    Jansen van Vuren, Petrus
    National Institute Communicable Disease, South Africa.
    Blixt, Ola
    University of Copenhagen, Denmark.
    Brun, Alejandro
    Institute Nacl Invest and Tecnol Agriculture and Alimentaria, Spain.
    Weber, Friedemann
    Philipps University of Marburg, Germany; Justus Liebig University, Germany.
    Mirazimi, Ali
    Folkhälsomyndigheten, Sweden; National Vet Institute, Sweden; Karolinska Institute, Sweden.
    Immunization with DNA Plasmids Coding for Crimean-Congo Hemorrhagic Fever Virus Capsid and Envelope Proteins and/or Virus-Like Particles Induces Protection and Survival in Challenged Mice2017In: Journal of Virology, ISSN 0022-538X, E-ISSN 1098-5514, Vol. 91, no 10, article id UNSP e02076-16Article in journal (Refereed)
    Abstract [en]

    Crimean-Congo hemorrhagic fever virus (CCHFV) is a bunyavirus causing severe hemorrhagic fever disease in humans, with high mortality rates. The requirement of a high-containment laboratory and the lack of an animal model hampered the study of the immune response and protection of vaccine candidates. Using the recently developed interferon alpha receptor knockout (IFNAR(- / -)) mouse model, which replicates human disease, we investigated the immunogenicity and protection of two novel CCHFV vaccine candidates: a DNA vaccine encoding a ubiquitin-linked version of CCHFV Gc, Gn, and N and one using transcriptionally competent virus-like particles (tc-VLPs). In contrast to most studies that focus on neutralizing antibodies, we measured both humoral and cellular immune responses. We demonstrated a clear and 100% efficient preventive immunity against lethal CCHFV challenge with the DNA vaccine. Interestingly, there was no correlation with the neutralizing antibody titers alone, which were higher in the tc-VLP-vaccinated mice. However, the animals with a lower neutralizing titer, but a dominant cell-mediated Th1 response and a balanced Th2 response, resisted the CCHFV challenge. Moreover, we found that in challenged mice with a Th1 response (immunized by DNA/DNA and boosted by tc-VLPs), the immune response changed to Th2 at day 9 postchallenge. In addition, we were able to identify new linear B-cell epitope regions that are highly conserved between CCHFV strains. Altogether, our results suggest that a predominantly Th1-type immune response provides the most efficient protective immunity against CCHFV challenge. However, we cannot exclude the importance of the neutralizing antibodies as the surviving immunized mice exhibited substantial amounts of them. IMPORTANCE Crimean-Congo hemorrhagic fever virus (CCHFV) is responsible for hemorrhagic diseases in humans, with a high mortality rate. There is no FDAapproved vaccine, and there are still gaps in our knowledge of the immune responses to infection. The recently developed mouse models mimic human CCHF disease and are useful to study the immunogenicity and the protection by vaccine candidates. Our study shows that mice vaccinated with a specific DNA vaccine were fully protected. Importantly, we show that neutralizing antibodies are not sufficient for protection against CCHFV challenge but that an extra Th1-specific cellular response is required. Moreover, we describe the identification of five conserved B-cell epitopes, of which only one was previously known, that could be of great importance for the development of diagnostics tools and the improvement of vaccine candidates.

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  • 243.
    Hinkula, Jorma
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Petkov, S
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Ljungberg, K
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Hallengärd, D
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Bråve, A
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Isaguliants, M
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Falkeborn, Tina
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Sharma, Sumit
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Liakina, V
    Faculty of Medicine, Vilnius University 2, 08661 Vilnius, Lithuania.
    Robb, M
    U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, 20892 MD, USA / Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, 20892 MD, USA.
    Eller, M
    U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, 20892 MD, USA / Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, 20892 MD, USA.
    Moss, B
    Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892 MD, USA.
    Biberfeld, G
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Sandström, E
    Department of South Hospital, Karolinska Institutet, 11883 Stockholm, Sweden.
    Nilsson, C
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Markland, K
    Clinical Research Center and Vecura, Karolinska University Hospital, 17176 Stockholm, Sweden.
    Blomberg, P
    Clinical Research Center and Vecura, Karolinska University Hospital, 17176 Stockholm, Sweden.
    Wahren, B
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    HIVIS-DNA or HIVISopt-DNA priming followed by CMDR vaccinia-based boosts induce both humoral and cellular murine immune responses to HIV.2017In: Heliyon, ISSN 2405-8440, Vol. 3, no 6, article id e00339Article in journal (Refereed)