liu.seSearch for publications in DiVA
Change search
Refine search result
12 1 - 50 of 57
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Andersson, Christoffer R.
    et al.
    Örebro University, Sweden.
    Bergquist, Jonas
    Uppsala University, 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.
    Ström, Jakob
    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. Örebro University, Sweden.
    Comparisons between commercial salivary testosterone enzyme-linked immunosorbent assay kits2017In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 77, no 8, p. 582-586Article in journal (Refereed)
    Abstract [en]

    Introduction: Measuring testosterone concentrations is of interest both in clinical situations and for research, the latter expanding rapidly during recent years. An increased demand for convenient methods has prompted a number of companies to develop enzyme-linked immunosorbent assay (ELISA) kits to measure testosterone concentrations in saliva. However, the inter-comparability of kits from different manufacturers have yet to be determined. Aim of study: The aim of this study was to compare commercially available ELISA kits from four different manufacturers (Salimetrics, IBL, DRG and Demeditec). Methods: Saliva was collected from 50 participants (25 men and 25 women). Each sample was analysed by the four ELISA kits. Results: The correlations between the ELISA kits from Demeditec, DRG and Salimetrics were moderate to high with r-values amp;gt;.77; however, proportional errors between the methods calls for caution. The ELISA kit from IBL malfunctioned and no results from this kit was obtained. Conclusions: Results from studies using the ELISA kits from Demeditec, DRG and Salimetrics are generally comparable; however, translation using the formulae presented in the current study could increase the accuracy of these comparisons.

  • 2.
    Aspevall, O
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of health and environment.
    Forsum, Urban
    Linköping University, Faculty of Health Sciences. Linköping University, Department of health and environment. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Microbiology.
    Kjerstadius, T
    Hallander, H
    Evaluation of two methods for improving quality of diagnosis of bacteriuria by culture in primary healthcare.2000In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 60, p. 387-394Article in journal (Refereed)
  • 3.
    Aspevall, O
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of health and environment.
    Kjerstadius, T
    Lindberg, L
    Hallander, H
    Performance of Uricult TrioR assessed by a comparison method and external control panels in primary healthcare.2000In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 60, p. 381-386Article in journal (Refereed)
  • 4.
    Bengtsson, Torbjörn
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology.
    Frydén, A
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology.
    Zalavary, S
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology.
    Whiss, Per A
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Pharmacology.
    Orselius, Kristina
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology.
    Grenegård, Magnus
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Pharmacology.
    Platelets enhence neutrophil locomotion: evidence for a role of P-selectin1999In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 59, p. 439-450Article in journal (Refereed)
  • 5.
    Bengtsson, Torbjörn
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology.
    Grenegård, Magnus
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Pharmacology.
    Grenegård, M
    Leucocyte activation by collagen-stimulated platelets in whole blood2002In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 62, no 6, p. 451-462Article in journal (Refereed)
    Abstract [en]

    Interaction between vascular cells plays an important role in the initial phases of the inflammatory process, but the mechanisms responsible for cell-cell communication are not fully understood. In this study, activation of leucocytes and platelets in heparinized whole blood was assessed using lumi-aggregometry. This technique enables simultaneous measurement of aggregation and oxygen radical production by monitoring impedance and luminol-amplified chemiluminescence (CL), respectively. Collagen induced aggregation and CL, depending on dose, and markedly enhanced subsequent aggregation and CL-response triggered by the chemotactic peptide formyl-methionyl-leucyl-phenylalanine (fMet-Leu-Phe). Collagen stimulation of whole blood down- and upregulated the expression of L-selectin and CD11b, respectively. Monoclonal antibodies against sialyl LewisX and P-selectin caused a pronounced inhibition of the oxidative burst, triggered by collagen itself or by a combination of collagen and fMet-Leu-Phe. Furthermore, the Arg-Gly-Asp-Ser(RGDS)-peptide effectively inhibited collagentriggered aggregation and CL, and the subsequent enhancement of the fMet-Leu-Phe-induced responses. This suggests that fibrinogen plays a part in linking platelet GpIIb/IIIa with CD11b on the leucocyte surface. However, neither anti-CD11b nor the PI-peptide (containing the ?-chain motif in fibrinogen that interacts with CD11b) counteracted the stimulatory effects of activated platelets on leucocyte functions. The selectin- and integrin-antagonizing substances were ineffective on the CL-responses induced by fMet-Leu-Phe itself. This study suggests that, through selectin- and integrin-dependent interaction, activated platelets potentiate leucocyte aggregation and oxygen radical production, which might be important for the outcome of inflammatory reactions.

  • 6.
    Berg, Sören
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Anaesthesiology. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Engman, A
    Stockholm.
    Holmgren, Susanna
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Obstetrics and gynecology. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Lundahl, T
    Västervik.
    Laurent, T
    Uppsala.
    Increased plasma hyaluronan in severe pre-eclampsia and eclampsia2001In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 61, no 2, p. 131-138Article in journal (Refereed)
    Abstract [en]

    Pre-eclampsia is a serious multi-system disorder with general endothelial disease, often with a component of hepatic dysfunction. The pathogenesis of pre-eclampsia is not fully understood, and no specific diagnostic tests are available for early and reliable diagnosis, or for monitoring of the disease process. Hyaluronan is an extracellular matrix polysaccharide present at low concentrations in plasma. Normally, it is rapidly eliminated from the blood by the liver. Increased concentrations of circulating hyaluronan are seen in conditions with impaired hepatic function such as liver cirrhosis, and hyaluronan concentrations have previously been used to evaluate hepatic function in other diseases. In the present study, 11 pregnant women admitted to the intensive care unit with severe pre-eclampsia or eclampsia were studied. As control 31 healthy pregnant women, 18 undergoing vaginal delivery and 13 caesarean section, were included. Plasma hyaluronan was measured before and after delivery. Increased concentrations of plasma hyaluronan were found in the pre-eclampsia group both before (171 (75-586) ╡g/L (p < 0.01) and after delivery (215 (124-768) ╡g/L (p < 0.001) (median and inter-quartile range), as compared to both caesarean section (13 (7-28) ╡g/L before and 28 (18-48) ╡g/L after delivery) and vaginal delivery healthy controls (12 (8-24) ╡g/L before and 30 (13-63) ╡g/L after delivery). In the control groups, a small increase in plasma hyaluronan was seen after delivery, after both caesarean section (p < 0.05) and vaginal delivery (p < 0.01). In conclusion, plasma hyaluronan is increased in severe pre-eclampsia and eclampsia. The cause of the increase is unknown.

  • 7.
    Bjerner, Johan
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Biernat, Donata
    Oslo Univ Hosp, Dept Med Chem, Radium Hosp, Oslo, Norway.
    D. Fossa, Sophie
    Oslo Univ Hosp, Dept Oncol, Radium Hosp, Oslo, Norway.
    Bjoro, Trine
    Oslo Univ Hosp, Dept Med Chem, Radium Hosp, Oslo, Norway.
    Reference intervals for serum testosterone, SHBG, LH and FSH in males from the NORIP project2009In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 69, no 8, p. 873-879Article in journal (Refereed)
    Abstract [en]

    Reference intervals were calculated for male testosterone, SHBG, FSH and LH in serum from 599 individuals in the NORIP study. At 30 years of age, reference limits were calculated to 10.4-32.6 nmol/L testosterone, 13.5-57.4 nmol/L SHBG, 1.93-9.7 IU/L LH and 1.5-10.3 IU/L FSH, at 50 years, 9.3-31.3 nmol/L (testosterone), 18.4-75.6 nmol/L (SHBG), 2.01-10.4 IU/L (LH) and 2.04-12.4 IU/L (FSH), and at 70 years 8.6 to 30.7 nmol/L (testosterone), 27.8-101 nmol/L (SHBG), 2.22-11.2 IU/L (LH) and 2.71-14.2 IU/L (FSH). All age-+related changes were statistically significant. Reference intervals were also calculated for indices derived from testosterone, SHBG and albumin. Free androgen index, simply the ratio between testosterone and SHBG, returned results differing from the other elaborate indices, and the study thus favors use of a more elaborate index such as calculated free testosterone (CFT).

  • 8. Blomgren, J
    et al.
    Ekman, Bertil
    Andersson, P-O
    Arnqvist, Hans
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of cell biology. Östergötlands Läns Landsting, Centre for Medicine, Department of Endocrinology and Gastroenterology UHL.
    Non-physiological levels of circulating cortisol in growth hormone-treated hypopituitary adults after conventional cortisone substitution2004In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 64, no 2, p. 132-139Article in journal (Refereed)
    Abstract [en]

    Objective: To assess the usefulness of measuring plasma cortisol profiles in growth hormone-treated hypopituitary adults and to compare these with cortisol levels in healthy controls. Methods: Eleven ACTH-deficient adult patients received 12.5 mg cortisone-acetate orally at 16.00 h and 25 mg at 07.00 h. The patients arrived in the ward at 12.00 h. After tablet intake at 16.00 h, samples for serum cortisol were taken at hourly intervals for the next 24 h, except between 07.00 and 12.00 h when samples were drawn every half hour, 24-h urinary free cortisol (24-h-UFC) excretion was collected simultaneously. For comparison, 8 healthy controls were investigated. Results: The patients had circulating cortisol levels with very low plasma cortisol at 07.00 h before their morning dose of cortisone acetate. At the same time period, controls had their highest plasma cortisol levels. After tablet intake the patients had a rapid initial absorption of cortisol, but a marked variability in the morning peak levels (Cmax), and the Cmax was in general higher and occurred 90 min later than the Cmax in the controls. The 24-h-UFC excretion and 24-h area under the curve (24-h-AUC) did not differ between patients and controls. The female patients had higher 24-h-AUC for plasma cortisol (p=0.032) and tended to have higher plasma cortisol peaks in the morning, but had levels of 24-h-UFC similar to those of the male patients. Conclusions: Conventional cortisone substitution with a twice-daily replacement regimen in hypopituitary adults results in abnormal circulating cortisol profiles with low or non-measurable morning values and variable individual peaks. This suggests that the present dosing schemes have to be improved and that cortisone substitution should be individualized.

  • 9.
    Blomqvist, Henrik
    et al.
    Linköping University, Department of Medicine and Care, Internal Medicine. Linköping University, Faculty of Health Sciences.
    Olsson, Anders
    Linköping University, Department of Medicine and Care, Internal Medicine. Linköping University, Faculty of Health Sciences.
    Monocyte chemoattractant protein‐1 and CC‐chemokine receptor‐2 in severe hypercholesterolaemia2003In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 63, no 7-8, p. 513-519Article in journal (Refereed)
    Abstract [en]

    Objectives: To investigate whether plasma concentrations of monocyte chemoattractant protein‐1 (MCP‐1) and the gene expression of its receptor on the monocyte cell surface CCR‐2 were elevated above normal in subjects with asymptomatic, isolated hypercholesterolaemia and if statin treatment could influence this cytokine.

    Methods: The investigation was designed as a cross sectional study followed by a single, blind, treatment study of patients receiving pravastatin 80 mg/day for 8 weeks. The study included 23 patients with severe hypercholesterolaemia (LDL>5.2 mmol/L) and 39 normocholesterolaemic controls. Blood samples were obtained from patients and controls at baseline and from patients at end of the study and analysed for lipoproteins and inflammatory mediators: MCP‐1, high‐sensitivity C‐reactive protein (HS‐CRP). Isolated peripheral mononuclear cells were analysed for CCR‐2 gene expression.

    Results: Mean plasma LDL‐C was significantly higher in patients than in controls. No difference in plasma MCP‐1 levels or CCR‐2 gene expression was seen between the groups at baseline, nor were there any differences in plasma concentrations of CRP. After treatment with pravastatin, LDL‐C decreased by 31%. Treatment did not significantly affect the levels of MCP‐1 or CCR‐2 gene expression, nor was CRP affected by treatment with pravastatin.

    Conclusions: Our study does not support the view that MCP‐1 plasma levels and CCR‐2 gene expression in circulating monocytes are directly responsible for the monocyte recruitment into the arterial intima in patients with severe asymptomatic hypercholesterolaemia. In addition, the inflammatory response of a high concentration of LDL‐C in isolated asymptomatic hypercholesterolaemia is minute.

  • 10. Bolinder, J
    et al.
    Fernlund, P
    Borg, H
    Arnqvist, Hans
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of cell biology. Östergötlands Läns Landsting, Centre for Medicine, Department of Endocrinology and Gastroenterology UHL.
    Björk, E
    Blohmé, G
    Eriksson, JW
    Nyström, L
    Östman, J
    Sundkvist, G
    Hyperproinsulinemia segregates young adult patients with newly diagnosed autoimmune (type 1) and non-autoimmune (type 2) diabetes2005In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 65, no 7, p. 585-594Article in journal (Refereed)
    Abstract [en]

    Objective. To investigate whether measurements of proinsulin and/or intermediate proinsulin degradation products could be used to differentiate between autoimmune (type 1) and non-autoimmune (type 2) diabetes in young adults. Material and methods. Total proinsulin, intact proinsulin and 32,33 split proinsulin concentrations were measured in 25 patients aged 15-34 years with type 1 diabetes, as defined by the presence of at least two positive islet autoantibodies, and in 23 antibody-negative patients of similar age with type 2 diabetes, at the time of clinical onset of diabetes and at 3-4 months thereafter. Comparisons were made with data from 25 healthy subjects matched for gender and age. Results. Plasma levels of total proinsulin, intact proinsulin and 32,33 split proinsulin were significantly increased 2-3-fold in the patients with newly diagnosed type 2 diabetes as compared with the controls, both in absolute terms (p<0.0001) and when related to circulating insulin (p<0.01-0.0002). In contrast, absolute proinsulin and 32,33 split proinsulin concentrations were significantly lower in patients with onset of type 1 diabetes than in controls. When proinsulin and split proinsulin release were related to plasma insulin, however, similar ratios were found in the type 1 diabetes patients and in controls. Using the 90th percentile for total proinsulin in the control group as the cut-off, the sensitivity and specificity for differentiation between autoimmune and non-autoimmune diabetes were 87% and 92%, respectively. At 3-4 months after clinical onset of diabetes, proinsulin secretion was still 2-3 times higher in type 2 than in type 1 diabetes patients (p<0.001). Conclusions. Young adult patients with newly diagnosed type 2 diabetes display disproportionate hyperproinsulinemia, whereas proinsulin secretion appears to be normal in patients with clinical onset of type 1 diabetes. Evaluation of proinsulin and 32,33 split proinsulin concentrations may be useful as a diagnostic tool in differentiating between autoimmune and non-autoimmune diabetes in young adults, particularly in those lacking islet autoantibodies at diagnosis. © 2005 Taylor & Francis.

  • 11.
    Bukmann Larsen, Pia
    et al.
    Slagelse Hospital, Denmark.
    Storjord, Elin
    Nordland Hospital, Norway; UiT, Norway.
    Bakke, Asne
    Stavanger University Hospital, Norway.
    Bukve, Tone
    Akershus University Hospital, Norway.
    Christensen, Mikael
    Aarhus University Hospital, Denmark.
    Eikeland, Joakim
    Oslo University Hospital, Norway.
    Engeland Haugen, Vegar
    Haukeland Hospital, Norway.
    Husby, Kristin
    Akershus University Hospital, Norway.
    McGrail, Rie
    Aarhus University Hospital, Denmark.
    Meier Mikaelsen, Solveig
    Sykehuset Innlandet, Norway.
    Monsen, Grete
    Noklus, Norway.
    Fogh Moller, Mette
    Herning Hospital, Denmark.
    Nybo, Jan
    Aalborg University Hospital, Denmark.
    Revsholm, Jesper
    Randers Regional Hospital, Denmark.
    Johanne Risoy, Aslaug
    Noklus, Norway; University of Bergen, Norway.
    Skalsvik, Unni Marie
    Nordland Hospital, Norway.
    Strand, Heidi
    Akershus University Hospital, Norway.
    Serrano Teruel, Reyes
    Noklus, Norway.
    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.
    The microINR portable coagulometer: analytical quality and user-friendliness of a PT (INR) point-of-care instrument2017In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 77, no 2, p. 115-121Article in journal (Refereed)
    Abstract [en]

    Regular measurement of prothrombin time as an international normalized ratio PT (INR) is mandatory for optimal and safe use of warfarin. Scandinavian evaluation of laboratory equipment for primary health care (SKUP) evaluated the microINR portable coagulometer (microINR((R))) (iLine Microsystems S.L., Spain) for measurement of PT (INR). Analytical quality and user-friendliness were evaluated under optimal conditions at an accredited hospital laboratory and at two primary health care centres (PHCCs). Patients were recruited at the outpatient clinic of the Laboratory of Medical Biochemistry, St Olavs University Hospital, Trondheim, Norway (n=98) and from two PHCCs (n=88). Venous blood samples were analyzed under optimal conditions on the STA-R((R))Evolution with STA-SPA+reagent (Stago, France) (Owren method), and the results were compared to capillary measurements on the microINR((R)). The imprecision of the microINR((R)) was 6% (90% CI: 5.3-7.0%) and 6.3% (90% CI: 5.1-8.3) in the outpatient clinic and PHCC2, respectively for INR 2.5. The microINR((R)) did not meet the SKUP quality requirement for imprecision 5.0%. For INR amp;lt;2.5 at PHCC2 and at both levels in PHCC1, CV% was 5.0. The accuracy fulfilled the SKUP quality goal in both outpatient clinic and PHCCs. User-friendliness of the operation manual was rated as intermediate, defined by SKUP as neutral ratings assessed as neither good nor bad. Operation facilities was rated unsatisfactory, and time factors satisfactory. In conclusion, quality requirements for imprecision were not met. The SKUP criteria for accuracy was fulfilled both at the hospital and at the PHCCs. The user-friendliness was rated intermediate.

  • 12.
    Chaireti, Roza
    et al.
    Karolinska Institute, Sweden.
    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.
    Bystrom, Birgitta
    Karolinska Institute, Sweden.
    Bremme, Katarina
    Karolinska Institute, Sweden.
    Larsson, Anders
    Uppsala University, Sweden.
    Inflammatory and endothelial markers during the menstrual cycle2016In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 76, no 3, p. 190-194Article in journal (Refereed)
    Abstract [en]

    Background The menstrual cycle exhibits a pattern of repeated inflammatory activity. The present study aims to evaluate inflammatory and endothelial markers during the two phases of a menstrual cycle. Methods The study cohort consisted of 102 women with regular menstrual cycles. Inflammatory and endothelial markers (interleukin-6 [IL-6], pentraxin-3 [PTX-3], hs-C reactive protein [hs-CRP], sE-selectin, sP-selectin, intracellular and vascular cell adhesion molecules [ICAM-1 and VCAM-1] and cathepsins L, B and S) were measured during the early follicular and the late luteal phase of a normal menstrual cycle. Results Pentraxin-3 (PTX-3) and hs-CRP were significantly higher during the follicular phase compared to the luteal phase (p &lt; 0.001 respectively p = 0.025). The other inflammatory and endothelial markers, with the exception of cathepsin B, were higher, albeit not significantly, during the follicular phase. Conclusions Inflammatory activity, expressed mainly by members of the pentraxin family, is higher during the early follicular compared to the luteal phase. This could be associated to menstruation but the exact mechanisms behind this pattern are unclear and might involve the ovarian hormones or an effect on hepatocytes.

  • 13.
    Coble, Britt-Inger
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of dermatology and venereology. Östergötlands Läns Landsting, Centre for Medicine, Department of Dermatology and Venerology in Östergötland.
    Nordahl-Åkesson, E
    Vinnerberg, Å
    Kihlström, Erik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Clinical Microbiology. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Microbiology.
    Urine-based testing for Chlamydia trachomatis using polymerase chain reaction, leucocyte esterase and urethral and cervical smears2006In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 66, no 4, p. 269-278Article in journal (Refereed)
    Abstract [en]

    The performance of Roche polymerase chain reaction (PCR) Amplicor to detect Chlamydia trachomatis in first-voided urine specimens from 422 males and 456 females attending two clinics for sexually transmitted infections was evaluated in comparison with cultures of urethral and cervical specimens. At the same time, the ability of leucocyte esterase (LE) in first-voided urine and the presence of leucocytes in urethral and cervical smears to identify C. trachomatis -infected individuals based on PCR and culture was determined. The prevalence of C. trachomatis infection was 10.9 % in men and 7.7 % in women. Sensitivity, specificity, positive predictive value and negative predictive value of Amplicor was 93.5 %, 99.7 %, 97.7 % and 99.2 % in males and 91.4 %, 99.5 %, 94.1 % and 99.3 % in females. All Chlamydia-infected men were identified by means of a combination of urethritis (≥4 leucocytes in the urethral smear) and/or a positive LE test in urine, although the specificity was only 42.2 %. In women, the combination of urethritis and/or cervicitis and/or a positive LE test identified 85.7 % of Chlamydia-infected patients with a specificity of 38.2 %. It is concluded that a combination of urethral and/or cervical smears and LE testing of urine can be used as a screening test to select patients, especially males, for specific C. trachomatis testing.

  • 14.
    Dabrosin, Charlotta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Obstetrics and gynecology.
    Technical aspects of microdialysis of human breast2001In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 61, no 4, p. 269-272Article in journal (Refereed)
    Abstract [en]

    In this study a technique for insertion of microdialysis catheters and the influence of the position of the catheters within normal human breast tissue were evaluated by measuring amino acids. Moreover, to assess variability over time, the levels of amino acids were measured during a period of 3 h. In nine healthy women two parallel microdialysis catheters were implanted, guided by a catheter for intravenous use, into the breast tissue. All insertions were successful and there were no complications. The levels of amino acids were equal in the two parallel catheters and varied less than 10% over a period of 3 h. Insertion of the microdialysis catheter via an intravenous catheter is suitable for the dense breast tissue. The position of the microdialysis catheter within the same breast seems to be of minor importance for measurements of amino acids. Thus, the described technique is a safe and reproducible way of investigating the human breast in vivo.

  • 15.
    Edvardsson, Maria
    et al.
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Local Health Care Services in Finspång.
    Sund-Levander, Märtha
    Linköping University, Department of Medical and Health Sciences, Division of Nursing Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Milberg, Anna
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Local Health Care Services in East Östergötland, Department of Advanced Home Care in Norrköping.
    Ernerudh, Jan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Immunology and Transfusion Medicine.
    Grodzinsky, Ewa
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Local Health Care Services in West Östergötland, Research & Development Unit in Local Health Care.
    Elevated levels of CRP and IL-8 are related to reduce survival time: 1-year follow-up measurements of different analytes in frail elderly nursing home residents2019In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 79, no 5, p. 288-292Article in journal (Refereed)
    Abstract [en]

    There are only few studies with specific focus on predictors of survival in nursing home residents (NHRs). The aim was to study whether 1-year changes in complete blood count (including hemoglobin, red blood cells, erythrocyte volume fraction, mean corpuscular volume, mean corpuscular hemoglobin concentration, white blood cells count and platelet count), C-reactive protein and interleukin-1 beta (IL-1 beta), IL-1Ra, IL-6, IL-8 and IL-10, are associated with 8-year survival in elderly NHRs, aged amp;gt;= 80 years. Complete blood count, C-reactive protein and interleukins were measured at baseline, after 6 and 12 months from 167 NHRs aged 80-101 years, mean age 88 +/- 4.5 years, 75% of whom were women. Dates of death were collected from the National Death Register 8 years after baseline. Levels of hemoglobin, red blood cells and mean corpuscular hemoglobin concentration were lower after 1-year, but higher for mean corpuscular volume and IL-1 beta, compared to baseline or 6 month follow-up. In the Cox regression model with a time-dependent covariate, raised levels of C-reactive protein and IL-8 were associated with reduced survival time. Elevated levels of C-reactive protein and IL-8 during 1-year follow-up were related to reduce lengths of survival in elderly NHRs.

  • 16. Enström, Camilla
    et al.
    Osman, Abdimajid
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Lindahl, Tomas
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    A genotyping method for VKORC1 1173C>T by Pyrosequencing® technology2008In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 68, no 5, p. 427-430Article in journal (Refereed)
    Abstract [en]

    Vitamin K epoxide reductase complex subunit 1 (VKORC1) is the site of inhibition by warfarin and other anti-vitamin K drugs during oral anticoagulant therapy. The SNP rs9934438 in intron 1 of VKORC1 (c.173+1000C>T or 1173C>T) discriminating the VKORC1*2 haplotype is associated with low warfarin dose requirement and unstable prothrombin time - international normalized ratio. To genotype this SNP, we have developed a rapid method using Pyrosequencing® technology. The proposed method takes a post-PCR sample preparation of less than 1 h and a DNA sequencing time of less than 15 min to genotype 96 samples. The current method was compared with a dHPLC method that we reported previously. Genotype frequencies at VKORC1 1173C>T for our Swedish population were 38 % wild-type, 40 % heterozygote and 22 % homozygote. The frequency of the T-allele was 0.42, which exactly matches the frequency previously reported for Germans. The current method can be used to determine whether patients initiating warfarin therapy are carriers of SNP 1173 C>T that is strongly associated with low warfarin dose requirement. © 2008 Informa UK Ltd (Informa Healthcare, Taylor & Francis AS).

  • 17.
    Garvin, Peter
    et al.
    Linköping University, Department of Department of Health and Society, Division of Preventive and Social Medicine and Public Health Science. Linköping University, Faculty of Health Sciences.
    Carstensen, John
    Linköping University, Department of Medical and Health Sciences, Health and Society. Linköping University, Faculty of Arts and Sciences.
    Kristenson, Margareta
    Linköping University, Department of Department of Health and Society, Division of Preventive and Social Medicine and Public Health Science. Linköping University, Faculty of Health Sciences.
    Pooling ambulatory saliva cortisol samples over consecutive days – as reliable as arithmetic means2008In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 68, no 6, p. 508-512Article in journal (Refereed)
    Abstract [en]

    Objective: When cortisol measurements are to be studied in large populations, cost-effective analyses are needed. This study aimed at testing whether one pooled cortisol value over three consecutive days is as reliable as using the arithmetic mean of the samples from the same measure points.

    Material and methods: Thirty participants aged between 45 and 69 collected saliva in salivettes immediately after awakening (t1), 30 min after awakening (t2) and in the evening (t3) during 3 consecutive days. A fixed volume from each of the samples (t1, t2 and t3) was pooled prior to laboratory analysis. Mean levels over 3 days for t1, t2 and t3 were compared to corresponding levels of pooled vials. Cortisol levels were analysed using a radio immunoassay.

    Results: All measures tested had high correlations between mean values and pooled samples, exemplified with diurnal deviation rdif t2–t350.974 (CI 0.946;0.987), and awakening response rdif t2–t150.982 (CI 0.963;0.991). There were no statistical differences between the pooled values and the arithmetic means.

    Conclusion: Pooling samples gave as reliable results as arithmetic means did. Pooling samples prior to laboratory analysis is a cost-effective method for measuring general diurnal cortisol variation in field research projects.

  • 18.
    Ghafouri, Bijar
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences.
    Larsson, Britt
    Linköping University, Department of Clinical and Experimental Medicine, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences.
    Sjörs, Anna
    Linköping University, Department of Clinical and Experimental Medicine, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences.
    Leandersson, Per
    Linköping University, Department of Clinical and Experimental Medicine, Occupational and Environmental Medicine. Östergötlands Läns Landsting, Heart and Medicine Centre, Occupational and Environmental Medicine Centre. Linköping University, Faculty of Health Sciences.
    Gerdle, Björn
    Linköping University, Department of Clinical and Experimental Medicine, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Sinnescentrum, Pain and Rehabilitation Centre.
    Interstitial concentration of serotonin is increased in myalgic human trapezius muscle during rest, repetitive work and mental stress - an in vivo microdialysis study2010In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 70, no 7, p. 478-486Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: The pathophysiology of trapezius myalgia is not fully elucidated. Serotonin (5-HT) is involved in modulation of nociception and hyperalgesia. Our aim was to compare the interstitial 5-HT levels of the trapezius muscle in women with chronic trapezius myalgia and in pain-free controls.

    MATERIALS AND METHODS: Microdialysate of the trapezius muscle collected every 20 minutes during rest, work (100 min) and stress (20 min) was used to study the dynamics of 5-HT in women with chronic trapezius myalgia (MYA; n=18) and in pain-free controls (CON; n=30).

    RESULTS: MYA had higher levels of 5-HT than CON at baseline, during repetitive work, during mental stress and during recovery. There were no significant time effects on 5-HT levels.

    CONCLUSION: 5-HT has the potential of a biomarker of chronic myalgia. Elevated levels of 5-HT may be involved in maintenance of habitual chronic pain and might contribute to increased pain during exercise by facilitating the effect of released algesic substances linked to such muscle demands.

  • 19.
    Grodzinsky, Ewa
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Department of Health and Society, General Practice. Östergötlands Läns Landsting, Local Health Care Services in the West of Östergötland, Unit of Research and Development in Local Health Care, County of Östergötland.
    Wiréhn, Ann-Britt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Department of Health and Society, General Practice. Östergötlands Läns Landsting, Local Health Care Services in the West of Östergötland, Unit of Research and Development in Local Health Care, County of Östergötland.
    Fremner, Eva
    Haglund, S
    Larsson, Lasse
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Persson, L-G
    Borgquist, Lars
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Department of Health and Society, General Practice. Östergötlands Läns Landsting, Local Health Care Services in the West of Östergötland, Unit of Research and Development in Local Health Care, County of Östergötland.
    Point-of-care testing has a limited effect on time to clinical decision in primary health care2004In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 64, no 6, p. 547-551Article in journal (Refereed)
    Abstract [en]

    Objective: To investigate the clinical logistics of laboratory routines at primary health care centres (PHCs). Design and methods: Prospective registration was carried out for each PHC using questionnaires during 2-week intervals between the end of November 2001 and mid-January 2002. The study included 9 PHCs in the county of Östergötland and 4 in the county of Jönköping, Sweden, with different numbers of blood tests analysed using point-of-care testing (POCT). Data for B-glucose, HbA1c, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), thyroid-stimulating hormone (TSH), T4, cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides were collected. Main outcome measures were median time from sampling to available test result (TATa) and median time from sampling to clinical decision (TATd), and the proportion of patients informed of the outcome of the blood test in question during the sampling occasion. Results: A total of 3542 samples were collected. The median TATa showed that B-glucose, ESR and CRP were immediately analysed at all 13 PHCs. For the other tests, TATa varied from immediately to about two days. The median TATd varied from immediately to about a week. When POCT was used, 30% of the patients were informed about the outcome of the test during the sampling occasion. Conclusion: POCT has a limited effect on the clinical logistics in PHCs.

  • 20.
    Hahn, Robert G.
    et al.
    Södertalje Sjukhus, Sweden.
    Jaarsma, Tiny
    Linköping University, Department of Social and Welfare Studies, Division of Nursing Science. Linköping University, Faculty of Medicine and Health Sciences.
    Waldréus, Nana
    Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Department of Social and Welfare Studies, Division of Nursing Science. Sodertalje Sjukhus, Sweden.
    Linssen, Gerard C. M.
    Hospital Grp Twente, Netherlands.
    Urine measurement indicates the plasma brain natriuretic peptide concentration during optimization of heart failure treatment2016In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 76, no 2, p. 112-117Article in journal (Refereed)
    Abstract [en]

    Aim: To assess the correlation between the amino-terminal pro-hormone brain natriuretic peptide (NT-proBNP) concentration in blood and urine during a period when actively adjusting the treatment of heart failure (HF). Methods: Plasma and urine analyses of NT-proBNP were compared in 51 patients on admission to and discharge from a nurse-led outpatient clinic where HF treatment was optimized. The median time between the two measurements was 42 days. Correlations were analyzed using linear regression, where R-2 is the degree of variability in the plasma NT-proBNP concentration that can be accounted for by the urinary NT-proBNP. Results: There was a statistically significant linear relationship between the urine and plasma concentrations of NT-proBNP on both occasions, but R-2 varied greatly depending on how the data were presented. The correlation between the raw data showed an R-2 of only 30%, and it almost doubled upon logarithm transformation, which shows that the variability (error) was concentration-dependent. Correction of the urinary NT-proBNP for urinary creatinine further increased R-2 for the logarithm-transformed correlation to 68% on admission and 76% on discharge. The highest R-2 (77%) was obtained when the relative changes in urinary NT-proBNP/creatinine between admission and discharge were compared with the corresponding relative changes in the plasma concentration. The sensitivity and specificity of the urine in indicating plasma concentration changes &gt; 10% were 82% and 86%, respectively. Conclusion: Relative changes in plasma NT-proBNP could be reliably estimated from urine samples during a period of optimization of HF treatment.

  • 21.
    Hambre, David
    et al.
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Vergara, Marta
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Lood, Yvonne
    Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Sweden.
    Bachrach-Lindström, Margareta
    Linköping University, Department of Medical and Health Sciences, Nursing Science. Linköping University, Faculty of Health Sciences.
    Lindström, Torbjörn
    Linköping University, Department of Medical and Health Sciences, Internal Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Endocrinology and Gastroenterology UHL.
    Nyström, Fredrik H
    Linköping University, Department of Medical and Health Sciences, Internal Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Endocrinology and Gastroenterology UHL.
    A randomized trial of protein supplementation compared with extra fast food on the effects of resistance training to increase metabolism2012In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 72, no 6, p. 471-478Article in journal (Refereed)
    Abstract [en]

    Objective. To prospectively evaluate the effects of resistance training combined with increased energy intake or protein-supplementation on lean body-mass, resting metabolic-rate (RMR) and cardiovascular risk factors. Methods. Twenty-four healthy males (aged 19-32 years) performed resistance exercise for 12 weeks aiming for at least 1 hour training-sessions 3 times a week. The participants were randomized to consume extra protein (33 g whey protein/day) or a meal of fast-food/day (1350 kcal, 41 g protein). Body-composition was measured with Dual-Energy X-ray Absorptiometry (DEXA) and RMR by indirect calorimetry. Fasting blood samples were drawn before and after the 3-month training period and after 12 months. Results. The body weight increased from 75.1 +/- 6.9 kg to 78.7 +/- 7.2 kg (p andlt; 0.0001), without differences between the groups. RMR increased from 1787 +/- 143 kcal/24 h to 1954 +/- 187 kcal/24 h (p andlt; 0.0001, N = 24), which was more than expected from the increase in lean body-mass (increase from 59.7 +/- 4.3 kg to 61.8 +/- 4.1 kg p = 0.004). Fasting serum-insulin levels increased in the fast-food group compared with the extra-protein group (p = 0.03). ApoB increased from 0.691 +/- 0.14 g/L to 0.768 +/- 0.17 g/L, p = 0.004, in the fast-food group only. Long-term follow up after 12 months showed that RMR, body weight, total fat and lean body-masses did not differ from baseline (n = 19). Conclusions. Resistance training for 12 weeks increased RMR and lean body-mass similarly when based on either an increased energy-intake or protein supplement. However, the increase in RMR was higher than expected from the increase in lean body-mass. Thus resistance training could potentially decrease the risk of obesity by induction of increased RMR.

  • 22. Herbertsson, H
    et al.
    Bengtsson, Torbjörn
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology.
    Role of platelets and the arachidonic acid pathway in the regulation of neutrophil oxidase activity2001In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 61, no 8, p. 641-649Article in journal (Refereed)
    Abstract [en]

    The intercellular mechanisms involved in platelet-mediated regulation of neutrophil function remain incompletely understood. This study investigated the role of the arachidonic acid pathway in the modulation of chemoattractant-induced production of oxygen metabolites, measured as luminol-amplified chemiluminescence (CL). We demonstrate that platelets dose-dependently inhibit the CL response in neutrophils stimulated with N-formyl-methionyl-leucyl-phenylalanine (fMLP). Incubation with eicosatetrayonic acid (ETYA), a combined cyclooxygenase and lipooxygenase inhibitor, dramatically decreased the fMLP-induced CL response in neutrophils, an effect that was further enhanced in the presence of platelets. The separate effects of eicosatriyonic acid (ETI) and indomethacin, specific inhibitors of lipoxygenase and cyclooxygenase, respectively, were significantly lower compared to the action of ETYA. On the contrary, impediment of arachidonic acid release with the phospholipase A2 inhibitor arachidonyl trifluoromethyl ketone (ATK) markedly increased the production of oxygen radicals triggered by fMLP. The addition of exogenous arachidonic acid clearly decreased the fMLP-induced CL response in neutrophils, which further strengthens a downregulating effect of arachidonic acid on oxidase activity. This inhibitory action of arachidonic acid, however, was reversed upon co-incubation with platelets. In conclusion, this study suggests that an accumulation of arachidonic acid, following chemotactic peptide stimulation, turns off neutrophil oxidase activity. Furthermore, platelets may support the synthesis of reactive arachidonic acid metabolites, which modulate oxygen radical production in neutrophils.

  • 23.
    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.

  • 24.
    Isaksson, Ida-Maria
    et al.
    Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry.
    Ström, Jakob
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Methods for 17 beta-oestradiol administration to rats2011In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 71, no 7, p. 583-592Article in journal (Refereed)
    Abstract [en]

    Several studies indicate that the beneficial or harmful effects of oestrogens in stroke are dose-dependent. Rats are amongst the most frequently used animals in these studies, which calls for thoroughly validated methods for administering 17 beta-oestradiol to rats. In an earlier study we characterised three different administration methods for 17 beta-oestradiol over 42 days. The present study assesses the concentrations in a short time perspective, with the addition of a novel peroral method. Female Sprague-Dawley rats were ovariectomised and administered 17 beta-oestradiol by subcutaneous injections, silastic capsules, pellets and orally (in the nut-cream Nutella (R)), respectively. One group received 17 beta-oestradiol by silastic capsules without previous washout time. Blood samples were obtained after 30 minutes, 1, 2, 4, 8, 12, 24, 48 and 168 hours and serum 17 beta-oestradiol (and oestrone sulphate in some samples) was subsequently analysed. For long-term characterisation, one group treated perorally was blood sampled after 2, 7, 14, 21, 28, 35 and 42 days. At sacrifice, uterine horns were weighed and subcutaneous tissue samples were taken for histological assessment. The pellets, silastic capsule and injection groups produced serum 17 beta-oestradiol concentrations that were initially several orders of magnitude higher than physiological levels, while the peroral groups had 17 beta-oestradiol levels that were within the physiological range during the entire experiment. The peroral method is a promising option for administering 17 beta-oestradiol if physiological levels or similarity to womens oral hormone therapy are desired. Uterine weights were found to be a very crude measure of oestrogen exposure.

  • 25.
    Jones, A Wayne
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry.
    Letter: Mode of classification of source material as citable items skews journal impact factor calculations2005In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 65, no 7, p. 623-625Article in journal (Other academic)
    Abstract [en]

    [No abstract available]

  • 26.
    Jones, A Wayne
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry.
    Hård, L
    How good are clinical chemistry laboratories at analysing ethylene glycol?2004In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 64, no 7, p. 629-634Article in journal (Refereed)
    Abstract [en]

    The results of an external proficiency test of clinical chemistry laboratories in Sweden when the target analyte was ethylene glycol (EG) are presented. Specimens of plasma were spiked with EG (10% w/v) to give assigned concentrations ranging from 5 to 50 mmol/L. Over a period of 6 years, two control specimens of plasma were sent for analysis on 21 occasions to between 14 and 20 participating laboratories as a declared proficiency trial. The analytical precision between and within laboratories was determined by spiking the plasma specimens with the same concentration of EG so that the results reported back could be considered a duplicate determination. On one occasion propylene glycol (PG) was substituted for EG without informing the participants. The standard deviation (SD) within laboratories expressed as the coefficient of variation (CV) was 4.5% compared with 11.4% between laboratories. Results reported by laboratories using gas chromatography (GC) were in good agreement with those when an enzymatic method was used. The between-laboratory SD increased with concentration of EG in the specimen and at a mean concentration of 18 mmol/L, the pooled SD was 4.11 mmol/L (CV = 23%). Four laboratories reported finding EG in plasma when PG was the diol present, three laboratories used an enzymatic method and one used GC. Clinical laboratories that provide a toxicology service should regularly participate in external quality assurance schemes that include low-molecular-weight alcohols such as EG. Efforts should be made to standardize the analytical methods used for toxicological analysis.

  • 27.
    Järemo, Petter
    et al.
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in the East of Östergötland, Department of Internal Medicine VHN.
    Milovanovic, Micha
    Linköping University, Department of Social and Welfare Studies, Health, Activity, Care. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in the East of Östergötland, Department of Internal Medicine VHN.
    Buller, Caroline
    Östergötlands Läns Landsting, Local Health Care Services in the East of Östergötland, Department of Internal Medicine VHN.
    Nilsson, Staffan
    Linköping University, Department of Medical and Health Sciences, General Practice. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in the East of Östergötland, East County Primary Health Care.
    Winblad, Bengt
    Karolinska Institute, Sweden .
    P-selectin paradox and dementia of the Alzheimer type: Circulating P-selectin is increased but platelet-bound P-selectin after agonist provocation is compromised2013In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 73, no 2, p. 170-174Article in journal (Refereed)
    Abstract [en]

    Objective. Knowledge concerning the neurobiological importance of platelets in Alzheimers disease (AD) is sparse. P-selectin, which is located together with beta-amyloid precursor proteins in platelet alpha-granules, is also found in endothelial cells. Upon activation, P-selectin is relocated to cell surfaces where it acts as a receptor. Subsequently, the protein is cleaved from the membrane, to then be circulated. We investigated P-selectin behavior in AD dementia. Methods. We recruited 23 persons diagnosed moderate AD and 17 healthy elders without obvious memory problems. Circulating P-selectin was analyzed using an ELISA technique and flow cytometry was used to measure surface-bound P-selectin. The latter measure was carried out without provocation (platelet activity) and after in vitro agonist stimulation (platelet reactivity). A thrombin-receptor activating peptide (TRAP-6) (74 mu mol/L)) was used as a platelet agonist. Results. Soluble P-selectin was augmented in AD (p = 0.019) but platelet membrane-attached P-selectin did not differ from controls. AD diagnosis was associated with less surface-bound P-selectin after provocation. Significant results were obtained when 74 mu mol/L TRAP-6 was used as a platelet agonist (p = 0.0008). Conclusion. This study describes apparently paradoxical P-selectin reactions in moderate AD. While soluble P-selectin was higher in the disease group, membrane-attached P-selectin without agonist stimulation was no different between the disease and control groups. In contrast, AD was linked to lower platelet reactivity. The current findings encourage further research into this P-selectin paradox and its relevance for AD and, perhaps, other types of dementia as well.

  • 28. Kaminskas, A
    et al.
    Ziedén, Bo
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Internal Medicine. Östergötlands Läns Landsting, MKC-2, GE: endomed.
    Elving, B
    Linköping University, Faculty of Health Sciences. Linköping University, Department of health and environment. Östergötlands Läns Landsting, FHVC - Folkhälsovetenskapligt centrum, Förebygg.med.
    Kristenson, Margareta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of health and environment. Östergötlands Läns Landsting, FHVC - Folkhälsovetenskapligt centrum, Förebygg.med.
    Abaravicius, A
    Bergdahl, Björn
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Olsson, Anders
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Internal Medicine. Östergötlands Läns Landsting, MKC-2, GE: endomed.
    Kucinskiene, Z
    Adipose tissue fatty acids in men from two populations with different cardiovascular risk - the LiVicordia study.1999In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 59, p. 227-232Article in journal (Refereed)
  • 29.
    Lindahl, Tomas
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Fagerberg, Inger
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Larsson, A
    A new flow cytometric method for measurement of von Willebrand factor activity2003In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 63, no 3, p. 217-224Article in journal (Refereed)
    Abstract [en]

    Background: Patients with von Willebrand's disease may have normal levels of von Willebrand factor (VWF) antigen. It is therefore important to measure not only the antigen concentration but also the VWF activity. The most widely used method for measurement of VWF activity is the ristocetin cofactor assay (VWF:RCo), which is still crucial for the laboratory diagnosis of von Willebrand's disease (VWD). However, VWF:RCo has low precision, poor inter-laboratory reproducibility and requires an aggregometer. Many routine laboratories are not equipped with aggregometers but have flow cytometers instead. Methods: In this study a simple, precise and rapid flow cytometric assay was developed for the determination of von Willebrand factor activity, utilizing formalin-fixed platelets, fluorescein isothiocyanate-conjugated chicken anti-VWF antibodies (Fab-fragments) and phycoerythrine-conjugated anti-GPIIb/IIIa antibodies. Results: In samples from healthy controls and from patients with von Willebrand disease type 1, the flow cytometry assay showed good correlation with the VWF:RCo assay (r2 = 0.69) and the VWF antigen assays (r2 = 0.83), which was better than the correlation between the VWF:RCo assay and VWF antigen assays (r2 = 0.72). The flow cytometry method had good within-assay and total precision, C.V. 4,2%, and C.V. 7.5%, at a mean concentration of 0.40 IU/mL, respectively. Results obtained with the flow cytometric method on samples from two patients with von Willebrand disease 2B were lower than those obtained with the antigen method in accordance with the diagnosis. Conclusion: The accuracy and precision of the von Willebrand activity assay may be improved if a flow cytometer is utilized for measurement of the impact of ristocetin on binding of VWF to formalin-fixed platelets instead of measuring agglutination utilizing an aggregometer. In addition, our flow cytometric method assay enables measurement of von Willebrand factor activity at many more hospitals than was previously possible with the traditional ristocetin cofactor platelet aggregometry assay, and this trend is likely to increase in the future when routine hematological instruments are equipped with built-in flow cytometers.

  • 30.
    Lindahl, Tomas
    et al.
    Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Lundahl, T. H.
    Östergötlands Läns Landsting. Västervik Hospital, Sweden.
    Ranby, M
    Östergötlands Läns Landsting.
    Fransson, Sven-Göran
    Östergötlands Läns Landsting, Heart Centre, Department of Cardiology Thoracic Radiology.
    Clinical evaluation of a diagnostic strategy for deep venous thrombosis with exclusion by low plasma levels of fibrin degradation product D-dimer1998In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 58, no 4, p. 307-316Article in journal (Refereed)
    Abstract [en]

    Clinical research studies have indicated the possibility of diagnostic strategies for deep venous thrombosis (DVT), strategies which include a step where the diagnosis is excluded by low or undetectable plasma levels of fibrin degradation product D-dimer. In collaboration with two local hospitals in Sweden, three implementations of such a strategy are evaluated in this study. Procedures 1, 2 and 3 differed in the method for D-dimer determination, i.e. latex agglutination, immunofiltration and both, respectively. The evaluated procedures were performed in parallel and compared with the current procedure in the different hospitals. At both hospitals, the current procedure stipulated mandatory phlebography and laboratory analysis of acute coagulation status and routine haematology with report-back time of 2 h. Within the 2 h the hospitals clinical chemistry laboratories also determined plasma D-dimer by the two methods. Of 180 patients enrolled in the study, phlebography was successful in 155 and unsuccessful in 25. The phlebographies revealed 47 proximal DVT, 13 distal DVT and 95 no DVT. With Procedure 1, 53 patients (29%) were excluded in the D-dimer step. For these patients, 47 successful phlebographies revealed one proximal DVT and two distal DVT. With Procedure 2, 71 patients (39%) were excluded. For these patients, 65 successful phlebographies revealed two proximal DVT and four distal DVT. With Procedure 3,44 patients (24%) were excluded. For these patients, 41 successful phlebographies revealed two distal DVT. The negative predictive values of the D-dimer exclusion step, with 95% confidence intervals given within parentheses, were 96% (88-100%), 91% (84-98%) and 95% (89-100%) for Procedures 1, 2 and 3, respectively. The evaluation demonstrated that the diagnostic potential of D-dimer revealed in research studies can be achieved in clinical practice. The study also indicated that the positive diagnostic value of high levels of D-dimer may be of use in finalizing the diagnosis in the 14% of patients for whom phlebography is unsuccessful.

  • 31.
    Lindström, Torbjörn
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Internal Medicine. Östergötlands Läns Landsting, MKC-2, GE: endomed.
    Olsson, P-O
    Arnqvist, Hans
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Internal Medicine. Östergötlands Läns Landsting, MKC-2, GE: endomed.
    The use of human ultralente is limited by great intraindividual variability in overnight plasma insulin profiles2000In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 60, no 5, p. 341-348Article in journal (Refereed)
    Abstract [en]

    Our objective was to investigate the usefulness of human ultralente insulin as basal substitution overnight in patients with Type 1 diabetes treated with multiple insulin injection therapy by evaluating the free insulin and glucose profiles, the day-to-day variability and the impact of the time of injection. Methods: Ten patients with Type 1 diabetes and with good metabolic control (mean HbAlc 6.0%), treated with regular human insulin before breakfast, lunch and dinner and human ultralente (Ultratard«) before dinner or at bedtime, were studied. Plasma profiles of blood glucose and free insulin were measured on three occasions from 16.00 h until noon the next day. On two of these occasions Ultratard« was injected before dinner and once it was injected at bedtime in randomized order. Results: Injection of regular insulin before dinner resulted in a high insulin peak during the evening but no insulin peak was found that could be attributed to ultralente. The plasma concentration of free insulin at 03.00 h was 11.0▒1.9 mU/L and it slowly decreased to 6.4▒1.4 at 12.00 h after administration of ultralente at 17.00 h. There were no differences in the mean plasma insulin profiles compared to the other occasion when insulin was given at 17.00 h or at 22.00 h. On the other hand, the intra-individual day-to-day variability of mean insulin concentration during the night was considerable, often exceeding 50%. No differences were noted in the mean blood glucose profiles between the three occasions. Conclusion: Human ultralente insulin gives an insulin profile suitable for overnight substitution, but the great day-to-day variability limits its usefulness. It can be injected before dinner or at bedtime without any change in the insulin profile during the night.

  • 32.
    Lorr, David
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Lund, Anton
    University of Copenhagen, Denmark.
    Fredrikson, Mats
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Secher, Niels H.
    University of Copenhagen, Denmark.
    Tympanic membrane temperature decreases during head up tilt: relation to frontal lobe oxygenation and middle cerebral artery mean blood flow velocity2017In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 77, no 8, p. 587-591Article in journal (Refereed)
    Abstract [en]

    Introduction: Changes in blood flow influence temperature of surrounding tissues. Since the internal carotid artery (ICA) and internal jugular vein (IJV) neighbor the tympanic membrane, changes in their blood flow most likely determine changes in tympanic membrane temperature (TMT). We sought to evaluate the relationship between changes during a head-up tilt (HUT) induced reduction in cerebral blood flow (CBF) and TMT. Methods: Ten male subjects (age 19-28 years) underwent 50 degrees HUT until presyncope. A non-contact infrared sensor in the ear canal targeted the tympanic membrane. Changes in CBF were monitored by transcranial Doppler which determined the mean blood flow velocity in the middle cerebral artery (MCA V-mean) and by near infrared spectroscopy assessed frontal lobe oxygenation (ScO2), while skin blood flow (SkBF) was evaluated by laser Doppler flowmetry. Results: During HUT, TMT decreased by 0.6 degrees C (median; range 0.2 to 1.6 degrees C) related to a decrease in MCA V-mean (51.0 +/- 6.7 to 34.3 +/- 5.8 cm/sec (mean +/- SD); r=0.518, p=.002) and ScO2 (78.6 +/- 5.4% to 69.0 +/- 5.7%; r=0.352, p=.043), but not to SkBF (120 +/- 78 to 69 +/- 37 PU; r=0.245, p=.142). Conclusion: During an orthostatic challenge TMT decreases and the decrease is related to a reduction in CBF as indicated by MCA Vmean and ScO2, but not to SkBF. We consider TMT holds potential for non-invasive assessment of changes in cerebral perfusion.

  • 33.
    Magnusson, Bertil
    et al.
    SP Technical Research Institute Sweden.
    Ossowicki, Haakan
    Siemens.
    Rienitz, Olaf
    Phys Technical Bundesanstalt.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Clinical Chemistry.
    Routine internal- and external-quality control data in clinical laboratories for estimating measurement and diagnostic uncertainty using GUM principles2012In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 72, no 3, p. 212-220Article in journal (Refereed)
    Abstract [en]

    Healthcare laboratories are increasingly joining into larger laboratory organizations encompassing several physical laboratories. This caters for important new opportunities for re-defining the concept of a laboratory to encompass all laboratories and measurement methods measuring the same measurand for a population of patients. In order to make measurement results, comparable bias should be minimized or eliminated and measurement uncertainty properly evaluated for all methods used for a particular patient population. The measurement as well as diagnostic uncertainty can be evaluated from internal and external quality control results using GUM principles. In this paper the uncertainty evaluations are described in detail using only two main components, within-laboratory reproducibility and uncertainty of the bias component according to a Nordtest guideline. The evaluation is exemplified for the determination of creatinine in serum for a conglomerate of laboratories both expressed in absolute units (mu mol/L) and relative (%). An expanded measurement uncertainty of 12 mu mol/L associated with concentrations of creatinine below 120 mu mol/L and of 10% associated with concentrations above 120 mu mol/L was estimated. The diagnostic uncertainty encompasses both measurement uncertainty and biological variation, and can be estimated for a single value and for a difference. This diagnostic uncertainty for the difference for two samples from the same patient was determined to be 14 mu mol/L associated with concentrations of creatinine below 100 mu mol/L and 14 % associated with concentrations above 100 mu mol/L.

  • 34.
    Modell, B.
    et al.
    UCL Centre for Health Informatics and Multiprofessional Education (CHIME), UCL Centre of Health Informatics and Multiprofessional Education, Holborn Union Building, Whittington Campus, Highate Hill, London N19 5LW, United Kingdom.
    Darlison, M.
    UCL Centre for Health Informatics and Multiprofessional Education (CHIME).
    Birgens, H.
    Department of Haematology, Herlev Hospital, University of Copenhagen, Herlev, Denmark.
    Cario, H.
    Department of Pediatrics, University Hospital Ulm, Ulm, Germany.
    Faustino, P.
    Centro de Genetica Humana, Sector de Hemoglobinopatias, Instituto Nacional de Saude Dr. Ricardo Jorge, Lisbon, Portugal.
    Giordano, P.C.
    Hemoglobinopathies Laboratory, Department of Human and Clinical Genetics, Leiden University Medical Center, Leiden, Netherlands.
    Gulbis, B.
    Department of Clinical Chemistry, C.U.B. Hôpital Erasme, Brussels, Belgium.
    Hopmeier, P.
    Department of Laboratory Medicine and Blood Bank, Rudolfstiftung Hospital, Vienna, Austria.
    Lena-Russo, D.
    Faculte de Medecine de Marseille, Centre d'Enseignement et de Recherche en Genetique Medicale (CERGM), Marseille, France.
    Romao, L.
    Centro de Genetica Humana, Sector de Hemoglobinopatias, Instituto Nacional de Saude Dr. Ricardo Jorge, Lisbon, Portugal.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Epidemiology of haemoglobin disorders in Europe: An overview2007In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 67, no 1, p. 39-69Article, review/survey (Refereed)
    Abstract [en]

    Objective. As a result of global population movements, haemoglobin disorders (thalassaemias and sickle cell disorders) are increasingly common in the formerly non-indigenous countries of Northern and Western Europe and in the indigenous countries of Southern Europe. This article presents an overview of the changing picture and a method for assessing service needs. Method. Data on country of birth or ethnic origin of residents are adjusted to obtain the estimated proportions of residents and births in non-indigenous groups at risk for haemoglobin disorders in European countries. The results are combined with prevalence data in each country of origin to obtain country prevalence estimates. Service indicators (annual tests or other interventions required to ensure equitable delivery of treatment and prevention) are then derived by country. Results. Haemoglobin disorders now occur at comparable frequency throughout Northern, Western and Southern Europe. Annually, there are more affected conceptions in Northern and Western than in Southern Europe, and sickle cell disorders are more common than thalassaemias. There is growing need for health policy-makers to support motivated professionals working to develop optimal patient care, carrier diagnosis, genetic counselling and access to prenatal diagnosis throughout the Region. Conclusion. There is a strong case for pan-European collaboration on haemoglobin disorders to share policies, standards and the instruments required to support them. These include methods for needs assessment, service standards, education and information strategies and materials, and methods for evaluating service delivery. © 2007 Taylor & Francis.

  • 35.
    Mörelius, Evalotte
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Pediatrics . Linköping University, Faculty of Health Sciences.
    Nelson, Nina
    Linköping University, Department of Clinical and Experimental Medicine, Pediatrics . Linköping University, Faculty of Health Sciences.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Saliva collection using cotton buds with wooden sticks: a note of caution2006In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 66, no 1, p. 15-18Article in journal (Refereed)
    Abstract [en]

    The aims of the present study were to investigate whether the cotton-tipped applicators (cotton buds) used to collect saliva in infants can be stored un-centrifuged prior to cortisol analysis, and to test whether there is any difference in results between wooden and plastic-shafted sticks. Saliva was collected from 10 healthy adults using 6 cotton buds, i.e. 3 with wooden sticks and 3 with plastic sticks. The samples were then centrifuged at three different time-points: immediately after collection, after 24 h and after 48 h. Using cotton buds with wooden sticks, median salivary cortisol was significantly lower after 24 h (40 %) (p<0.001) and after 48 h (49 %) (p<0.001) of storage than it was of the samples centrifuged immediately. There was no significant difference between the samples centrifuged immediately and those centrifuged after 24 h and 48 h when saliva was collected using the cotton buds with plastic sticks. It is concluded that cotton buds with wooden sticks should not be used in studies of salivary cortisol unless it is possible to centrifuge the saliva immediately. Moreover, it is inadvisable to alternate between cotton buds with wooden and plastic sticks in the same study when collecting saliva for analysis of cortisol.

  • 36.
    Nayeri, Fariba
    et al.
    Linköping University, Department of Molecular and Clinical Medicine, Infectious Diseases. Linköping University, Faculty of Health Sciences.
    Nilsson, I.
    Laboratories of Clinical Chemistry, Kalmar County Hospital Hospital, Kalmar, Sweden.
    Brudin, L.
    Department of Physiology, County Hospital, Kalmar, Sweden.
    Almer, Sven
    Linköping University, Department of Molecular and Clinical Medicine, Gastroenterology and Hepatology. Linköping University, Faculty of Health Sciences.
    Stability of faecal hepatocyte growth factor determination2004In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 64, no 6, p. 589-597Article in journal (Refereed)
    Abstract [en]

    In order to evaluate the accuracy and reproducibility of determination of hepatocyte growth factor (HGF) levels in faeces, the stability of HGF in samples processed in different ways was investigated. An ELISA method was used for determination of HGF concentrations. Faeces samples from healthy controls and patients with infectious diarrhoea were studied. It was found that faeces HGF concentration remained stable irrespective of whether samples were freeze‐thawed several times, kept for 6, 12 or 24 h at room temperature or refrigerated for 6, 12, 24 or 36 h; the levels of HGF did not change significantly when samples were freeze‐dried. Adding protease inhibitor to the faeces samples did not affect the HGF levels. There were no significant differences between HGF levels using phosphate buffered saline (PBS) (pH 7.4) or NaCL as buffer, but it was observed that levels of HGF were significantly lower in the samples that were diluted in distilled water. Although both HGF and albumin through various mechanisms may increase in faeces during infectious diarrhoea, there was no significant correlation between faeces HGF levels and albumin levels, which might indicate local production of HGF in the bowel in response to infection. It is concluded that determination of faeces HGF levels is feasible with a high degree of stability. Increased HGF levels in faeces might represent a local production of HGF during bowel injury and might be of use as a diagnostic and monitoring assay.

  • 37.
    Nelson, Nina
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Pediatrics . Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Department of Paediatrics in Linköping.
    Arbring, Kerstin
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Internal Medicine .
    Theodorsson, Elvar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry.
    Neonatal salivary cortisol in response to heelstick: Method modifications enable analysis of low concentrations and small sample volumes2001In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 61, no 4, p. 287-291Article in journal (Refereed)
    Abstract [en]

    Measuring cortisol in saliva offers important advantages compared to measurement in plasma or serum. However, the sampling procedure and also the detection limit cause problems, especially in paediatric and neonatal care. We describe a simple and efficient sampling procedure, together with a modification of a radioimmunoassay, which enables analysis of low (down to 1 nmol/L) concentrations of salivary cortisol (10 times lower detection limit than in the original procedure). This setting was used in studying salivary cortisol concentrations before and after heelstick on healthy newborn infants. A significant rise (median 81%, p <0.01) in salivary cortisol as response to this invasive stressor was noted.

  • 38.
    Nielsen, Niels Erik
    et al.
    Linköping University, Department of Medicine and Care, Cardiology. Linköping University, Faculty of Health Sciences.
    Ahlner, Johan
    Linköping University, Department of Medicine and Care, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Malmstedt, J
    Linköping University, Department of Medicine and Care, Cardiology. Linköping University, Faculty of Health Sciences.
    Öhman, K. P.
    Linköping University, Department of Medical and Health Sciences, Endocrinology. Linköping University, Faculty of Health Sciences.
    Swahn, Eva
    Linköping University, Department of Medicine and Care, Cardiology. Linköping University, Faculty of Health Sciences.
    Plasma levels of cyclic GMP and endothelin in postmenopausal women with unstable coronary artery disease1999In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 59, no 5, p. 325-334Article in journal (Refereed)
    Abstract [en]

    Many women with typical anginal chest pain have normal coronary angiograms, which may be due to altered endothelial function. We evaluated the endothelial markers cyclic GMP (cGMP) and immunoreactive endothelin (ir-ET) regarding presence of coronary atherosclerosis in women with clinical signs of unstable coronary artery disease (CAD). Plasma levels of cGMP and ir-ET were determined in 118 patients and 84 controls. Ischaemia was evaluated at an exercise test. Of the patients 20% had normal vessels, 14% insignificant CAD and 66% significant stenosis at coronary angiography. Mean (95% CI) concentration of cGMP (nmol/l) was higher in patients than in controls (5.05 (4.53; 5.58) vs. 3.79 (3.34; 4.23)). Separating patients according to daily intake of nitroglycerin, only patients with this medication had significantly higher cGMP level (5.73 (4.88; 6.58)), whereas the difference between those without (4.35 (3.76; 4.94)) and controls disappeared. Patients with ischaemia at exercise test had higher cGMP level than those without (6.01 (5.13; 6.88) vs. 4.30 (3.66; 4.94)), even after adjusting for nitroglycerin treatment. ir-ET (pmol/l) was lower in patients with normal vessels than patients with coronary atherosclerosis (0.83 (0.78; 0.88) vs. 0.98 (0.92; 1.04)) and than the control group (0.91 (0.87; 0.94)). The difference between the control group and patients with atherosclerosis was also significant. Patients with unstable CAD and long-term nitroglycerin treatment have increased cGMP level. Patients with exercise-induced ischaemia have higher cGMP level than those without, irrespective of nitroglycerin treatment, which may reflect a general compensatory mechanism. Patients with normal vessels have low level of ir-ET, indicating different mechanisms for ischaemia/angina in these patients compared with patients with atherosclerosis.

  • 39.
    Nilsson, Caroline U.
    et al.
    Lund University, Sweden .
    Tynngård, Nahreen
    Linköping University, Department of Clinical and Experimental Medicine, Transfusion Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Immunology and Transfusion Medicine.
    Reinstrup, Peter
    Lund University, Sweden .
    Engstrom, Martin
    Lund University, Sweden .
    Monitoring fibrinolysis in whole blood by viscoelastic instruments: A comparison of ROTEM and ReoRox2013In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 73, no 6, p. 457-465Article in journal (Refereed)
    Abstract [en]

    Objective. Increased fibrinolysis with the risk of bleeding is a consequence of thrombolytic therapy and can also be seen in clinical situations such as acute trauma. Thrombelastography and thrombelastometry are viscoelastic coagulation instruments that can detect higher degrees of fibrinolysis; hyperfibrinolysis. A newer viscoelastic instrument is the ReoRox, which uses free oscillation rheometry to detect clot formation, strength and fibrinolysis. The ReoRox has a new test for detection of fibrinolysis, called ReoLyse. The aim of this study was to compare ReoRox with its new ReoLyse test with rotational thrombelastometry (ROTEM) in the monitoring of in vitro-induced fibrinolysis. Methods. Whole blood from 10 healthy volunteers was mixed with tissue plasminogen activator (t-PA) to obtain seven different plasma concentrations (0, 0.25, 0.5, 0.75, 1, 3 and 5 mu g/mL). Whole blood samples with the different t-PA plasma concentrations were analyzed with ROTEM EXTEM and FIBTEM tests, ReoRox standard test Fib1 (clot formation/strength) and ReoLyse (fibrinolysis) tests. Results. The fibrinolysis variables with the best dose-response effect were the ReoRox ReoLyse lysis variables and ROTEM EXTEM Time to complete lysis. However, these variables only detected high t-PA levels (andgt;1 mu g/mL). Conclusions. The new ReoRox ReoLyse test provides more information on fibrinolysis compared to the ReoRox Fib1 program. Neither ReoRox nor ROTEM could detect lower degrees of fibrinolysis. ReoRox is a valuable alternative to ROTEM to study high degrees of fibrinolysis and should be evaluated in clinical situations with increased fibrinolysis and during therapeutic thrombolysis.

  • 40.
    Olausson, Patrik
    et al.
    Linköping University, Department of Medical and Health Sciences, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences.
    Gerdle, Björn
    Linköping University, Department of Medical and Health Sciences, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthetics, Operations and Specialty Surgery Center, Pain and Rehabilitation Center.
    Ghafouri, Nazdar
    Linköping University, Department of Medical and Health Sciences, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthetics, Operations and Specialty Surgery Center, Pain and Rehabilitation Center.
    Karlsson, Linn
    Linköping University, Department of Medical and Health Sciences, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthetics, Operations and Specialty Surgery Center, Pain and Rehabilitation Center.
    Larsson, Britt
    Linköping University, Department of Medical and Health Sciences, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthetics, Operations and Specialty Surgery Center, Pain and Rehabilitation Center.
    Ghafouri, Bijar
    Linköping University, Department of Medical and Health Sciences, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthetics, Operations and Specialty Surgery Center, Pain and Rehabilitation Center. Östergötlands Läns Landsting, Heart and Medicine Center, Occupational and Environmental Medicine Center.
    Relative recovery over time – an in vivo microdialysisstudy of human skeletal muscle2013In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 73, no 1, p. 10-16Article in journal (Refereed)
    Abstract [en]

    BACKGROUND:

    The microdialysis technique is a method for sampling endogenous molecules from the interstitial compartments of varying tissues and relies on diffusion of molecules between the tissue and a perfusate via a membrane. Such samples do not allow determination of the true interstitial concentration but only a certain percentage. This gives rise to one of the most crucial parameter that needs to be considered for a dependable microdialysis; the relative recovery. Relative recovery states the efficiency of which an analyte is extracted from its external medium. Aim. To investigate the relative recovery of small molecules (< 20 kDa) such as lactate, fluid recovery and the reproducibility of the relative recovery at group and individual level of the microdialysis technique applied in muscle.

    MATERIALS AND METHODS:

    Using in vivo microdialysis of the trapezius muscle of 65 women from two separate occasions 4-6 months apart. Relative recovery of small molecules was measured from samples collected every 20 min during a period of 220 min.

    RESULTS:

    Good reproducibility at group level of catheters with cut-offs 100 and 20kDa were found. Furthermore, there was a high and steady relative recovery with an overall good fluid recovery. Poor reproducibility was found at the individual level for both catheters.

    CONCLUSIONS:

    This study demonstrates that when using microdialysis in skeletal muscle relative recovery is stable over time and is not affected by low-force exercise. Although there is a good reproducibility at group level this is not the case at the individual level. Thus in vivo, the relative recovery should be determined for each test subject and at each test occasion.

  • 41.
    Palmqvist, Elisabeth
    et al.
    Clinical Microbiology Laboratory University Hospital Linköping.
    Aspevall, Olle
    Clinical Microbiology Akademiska laboratorierna, Uppsala.
    Burman, Eva
    EQUALIS AB Uppsala.
    Nordin, Gunnar
    EQUALIS AB Uppsala.
    Svahn, Anita
    EQUALIS AB Uppsala.
    Forsum, Urban
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Clinical Microbiology . Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Microbiology.
    Difficulties for primary health care staff in interpreting bacterial findings on a device for simplified urinary culture2008In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 68, no 4, p. 312-316Article in journal (Refereed)
    Abstract [en]

    The reliability of interpretations of findings from dip-slide devices for culturing urine was investigated in a national Swedish external quality assessment (EQA) programme. Also investigated was the extent of improvement in the examination procedure achieved through personnel training programmes and information. According to Swedish national recommendations, dip-slide should only be used in primary health care (PHC) in cases of uncomplicated urinary tract infection (UTI) in females of childbearing age. The recommendations also define six possible outcomes of a dip-slide examination, outcomes that have formed the basis for the EQA programme since 2001. No improvement in ability to classify readings correctly into the six categories was noted for the period 2001 to 2006. Preparations containing 'mixed flora' presented participants with the greatest difficulty, with only 28% correct reports. The EQA programme, with educational components and voluntary participation, has not improved quality. The disappointing results might be a reflection of the limited effort and resources allocated by clinical microbiology laboratories for training and for sustaining proficiency in the evaluation of dip-slides. For these reasons, we cannot at present recommend the dip-slide technique for use in PHC settings. © 2008 Informa UK Ltd (Informa Healthcare, Taylor & Francis AS).

  • 42. Ronquist, G
    et al.
    Theodorsson, Elvar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Inherited, non-spherocytic haemolysis due to deficiency of glucose-6-phosphate dehydrogenase2007In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 67, no 1, p. 105-111Article in journal (Refereed)
    Abstract [en]

    The about 400 million individuals worldwide suffering from a hereditary deficiency of the enzyme glucose-6-phosphate dehydrogenase (G6PD) may experience different degrees of haemolytic anaemia. Haemoglobin is present in very high concentrations in the erythrocyte cytoplasm, at risk of falling out of solution if the internal environment or the haemoglobin itself is changed. G6PD is a crucial enzyme producing reduced glutathione in the erythrocyte cytoplasm for the purpose of protecting haemoglobin against oxidative damage. The presence of unopposed oxidizing agents leading to oxidation of the sulfhydryl bridges between parts of the haemoglobin molecule decrease the solubility of haemoglobin, leading to precipitations called Heinz bodies. The laboratory investigation of G6PD deficiency is commonly done by a quantitative spectrophotometric analysis or by a rapid fluorescent spot test detecting the generation of NADPH from NADP. Genetic tests based on polymerase chain reaction detect specific mutations and may be used for population screening, family studies, or prenatal diagnosis. © 2007 Taylor & Francis.

  • 43.
    Rousseau, Andreas
    et al.
    Linköping University, Department of Medical and Health Sciences, Anesthesiology. Linköping University, Faculty of Health Sciences.
    Abdiu, Avni
    Linköping University, Department of Biomedicine and Surgery, Plastic Surgery, Hand Surgery and Burns. Linköping University, Faculty of Health Sciences.
    Sjöberg, Folke
    Linköping University, Department of Biomedicine and Surgery, Plastic Surgery, Hand Surgery and Burns. Linköping University, Faculty of Health Sciences.
    Hyperoxaemia does not change concentrations of serotonin and beta‐thromboglobulin in blood of healthy humans2004In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 64, no 2, p. 81-85Article in journal (Refereed)
    Abstract [en]

    Background: The mechanisms of oxygen‐induced effects on blood vessels (vasoconstriction in hyperoxaemia and vasodilatation during hypoxaemia) are uncertain. Many investigators have suggested that the vasoconstriction seen during hyperoxia/hyperoxaemia is mediated through the endothelium as a result of either increased release or activity of vasoconstrictors (oxygen radicals, endothelin, norepinephrine, angiotensin II, or serotonin (5‐HT)), or reduced activity of vasodilators (prostaglandin E2 and nitric oxide). Serotonin has been assumed to have a central role.

    Methods: Eight healthy volunteers were exposed to FiO2 of 1.0 for 20 min and serum concentrations of serotonin and activated platelets were measured (indicated by concentrations of β‐thromboglobulin (β‐TG)).

    Results. During hyperoxaemia in humans, serum concentrations of serotonin and β‐TG remained unchanged.

    Conclusion: If serotonin is involved in oxygen‐induced vasoconstriction, the mechanism is more likely to be either a potentiating effect of serotonin on other vasoconstrictors or increased activity of serotonin on its receptor.

  • 44.
    Rånby, Mats
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Ramström, Sofia
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Svensson, P-O
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Lindahl, Tomas
    Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Clotting time by free oscillation rheometry and visual inspection and a viscoelastic description of the clotting phenomenon2003In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 63, no 6, p. 397-406Article in journal (Refereed)
    Abstract [en]

    An automated procedure for determination of clotting time in whole blood was validated by direct comparison with the reference method, visual clotting time determination. The procedure was based on a 10 Hz free oscillation rheometer (FOR) of our design, the ReoRox®4. Recalcified citrated blood samples (n=30), clotting in the range 4 to 20 min, were used in the validation. Every 30 s of the analysis, as the change in stiffness (ΔG*) of the sample was monitored by FOR, the sample cup was shortly removed from the FOR and its contents inspected for first signs of clotting, i.e. visual clotting time determination. Various FOR clotting criteria were attempted. Best correlation to visual clotting time was found when ΔG* reached 0.01 Pa, which yielded linear regression slope, intercept and r2 of 0.98, 0.09 min and 0.98, respectively. For comparison, six plasma samples were analyzed in the same way and gave almost the same results. The accuracy of the FOR determinations was checked by also analyzing, in parallel, portions of the sample with a conventional oscillation rheometer, a Bohlin VOR. The rationale is given for preferring ΔG* over G* as a FOR monitoring function in coagulation tests and for including median filtration of the primary FOR data. An extension of the FOR theory to include ΔG* and evidence in support of inhomogeneous blood clotting are also given.

  • 45.
    Sjöstrand, F.
    et al.
    Söder Hospital, Sweden.
    Berndtson, D.
    Lund University Hospital, Sweden.
    Olsson, J.
    Regional Hospital, Hudiksvall, Sweden.
    Strandberg, P.
    Söder Hospital, Sweden.
    Hahn, Robert G.
    Söder Hospital, Sweden.
    The osmotic link between hypoglycaemia and hypovolaemia2008In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 68, no 2, p. 117-122Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: Hypoglycaemia is regularly accompanied by hypovolaemia. To suggest a mechanism for this phenomenon, we reviewed data from eight studies conducted by our group and examined the circumstances under which rebound hypoglycaemia develops after intravenous infusion of glucose solutions.

    MATERIAL AND METHODS: Forty healthy volunteers and 40 patients received a total of 122 infusions of glucose solutions at different rates, volumes and concentrations. Plasma glucose and the haemodilution were measured repeatedly during and for at least 2 h after the infusions ended. Glucose kinetics was calculated using a one-compartment turnover model and the plasma volume expansion was estimated from changes in Hb.

    RESULTS: A strong linear correlation was found between the glucose level and the plasma volume expansion in all series of experiments (p<0.001). After infusion, there was a risk of hypoglycaemia and hypovolaemia developing in healthy volunteers with a high glucose clearance and when infusing glucose solutions of higher concentrations than 2.5 %. Few and mild hypoglycaemic events occurred in patients with insulin resistance, such as in diabetics and in those undergoing surgery. The immediate linear relationship between hypoglycaemia and hypovolaemia suggests an osmotic link between the two parameters. More specifically, infused fluid accompanies glucose during uptake into the cells, while volume expansion by the same fluid has already elicited an effective diuretic response.

    CONCLUSION: Hypovolaemia is a consequence of hypoglycaemia after intravenous infusion of glucose solution and is caused by the osmotic translocation of fluid from the extracellular to the intracellular fluid space that occurs despite effective renal elimination.

  • 46.
    Ström, Jakob O.
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Substantial discrepancies in 17β-estradiol concentrations obtained with three different commercial direct radioimmunoassay kits in rat sera2008In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 68, no 8, p. 806-813Article in journal (Refereed)
    Abstract [en]

    The extensive use of estrogen for contraception and amelioration of post-menopausal symptoms has made it the subject of substantial recent research efforts. Ovariectomized (ovx) rats treated with exogenous ovarial hormones constitute important tools in the investigation of the effects and mechanisms of estrogen actions. The crucial need to control and to monitor plasma levels of 17β-estradiol calls for accurate, precise and robust assay methods. The performance of direct radioimmunoassays (RIAs) for measurement of 17β-estradiol has previously been reported for human samples, but – to our knowledge – not for rat samples. In the current study, 552 serum samples from ovx, native and hormone treated rats were used to compare the performance of three commercially manufactured direct RIAs from the companies DPC (Siemens Healthcare Diagnostics Inc., formerly Diagnostic Products Corporation), DSL (Diagnostic Systems Labs) and MPB (MP Biomedicals, formerly ICN Biomedicals). Substantial differences in results between the three assay methods were found when measuring serum 17β-estradiol concentrations. The following formulas, describing the relation between the different methods’ results, were obtained using weighted Deming’s orthogonal regression (all regression formulae in the abstract are based on pg/mL): DSL= 0.43*DPC+12.3, MPB= 2.1*DPC+84.7 and DSL= 4.8*MPB+22.2. Furthermore, a preceding diethyl ether extraction step of the serum appears to impair the RIAs’ performances in the present samples: DPCex= 0.39*DPCunex+0.76, DSLex= 0.32*DSLunex-1.7 and MPBex= 0.22*MPBunex+1.4.

  • 47.
    Ström, Jakob O.
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Order of magnitude differences between methods for maintaining physiological 17β-estradiol concentrations in ovariectomized rats2008In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 68, no 8, p. 814-822Article in journal (Refereed)
    Abstract [en]

    The use of animal, especially rat, models, is crucial for elucidating the biological effects and mechanisms of the widely used hormone 17β-estradiol. Unfortunately there is a lack of consensus on optimal means of obtaining and maintaining physiological 17β-estradiol concentrations in plasma. This may be the reason for varying results in several studies including the disagreement on whether 17β-estradiol is neuroprotective or not. Very few studies have been devoted to investigating the characteristics and biological relevance of different methods of 17β-estradiol administration. We therefore ovariectomized 75 Sprague-Dawley rats and, following a 2 weeks wash-out period, administered 17β-estradiol using three different methods; daily injections (10 µg 17β-estradiol/kg), slow-release pellets (0.25 mg 60 day-release pellets, 0.10 mg 90 day-release pellets) and silastic capsules (with/without wash-out periods) (silastic laboratory tubing, inner/outer diameter: 1.575/3.175 mm, filled with 20 mm columns of 180 µg 17β-estradiol/mL sesame oil). Further 45 animals were used as ovariectomized and native controls, studied in different parts of the estrous cycle. Silastic capsules produced concentrations of 17β-estradiol within the physiological range for 4-5 weeks independent of whether a prior wash-out period was included or not. The slow-release pellets, irrespective of dose or release period, resulted in initial concentrations which were an order of magnitude above physiological concentrations during the first two weeks followed by a substantial decrease. Daily injections resulted in increasing 17β-estradiol concentrations, however within physiological levels. Silastic capsules are conveniently manufactured and used, and are superior to pellets and injections in reliably producing long-term 17β-estradiol concentrations within the physiological range.

  • 48.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Advanced statistics and data analysis in laboratory medicine: steep learning curve but substantial rewards2008In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 68, no 6, p. 434-436Article in journal (Other academic)
    Abstract [en]

    None available

  • 49.
    Theodorsson, Elvar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Haemochromatosis, hepcidin and disorders of iron metabolism: Fields of substantial clinical relevance and current advances2006In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 66, no 2, p. 79-82Article in journal (Other academic)
    Abstract [en]

    [No abstract available]

  • 50.
    Theodorsson, Elvar
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Birgens, H
    Hagve, TA
    Haemoglobinopathies and glucose-6-phosphate dehydrogenase deficiency in a Scandinavian perspective2007In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 67, no 1Article in journal (Refereed)
    Abstract [en]

    Haemoglobinopathies (mainly thalassaemia and sickle-cell anaemia syndromes) and glucose-6-phosphate dehydrogenase deficiency (G6PD) are globally among the most prevalent single-genomic diseases. About 3 % of the world's population are heterozygotic for β-thalassaemia and about 1-2 % for sickle-cell anaemia, and it is estimated that more than 400 million people are affected by G6PD deficiency worldwide. The disorders are most prevalent in the Mediterranean area, in Asia and Africa. The Scandinavian countries, among others, have seen a boom in immigration during the past 20 years, and therefore migration makes haemoglobinopathies as well as G6PD deficiency increasingly more important from a differential diagnostic perspective in most countries. The purpose of the present special issue of the Journal is to summarize current epidemiological data and elucidate trends and practices in the laboratory diagnosis of these disorders. © 2007 Taylor & Francis.

12 1 - 50 of 57
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf