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  • 1.
    Ahn, Song-Ee
    et al.
    Linköping University, Department of Behavioural Sciences and Learning, Education and Adult Learning. Linköping University, Faculty of Educational Sciences.
    Rimpiläinen, Sanna
    University of Gothenburg.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Fenwick, Tara
    University of Stirling.
    Abrandt Dahlgren, Madeleine
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Learning in Technology-Enhanced Medical Simulation:Locations and Knowings2015In: Professions & Professionalism, ISSN 1893-1049, E-ISSN 1893-1049, Vol. 5, no 2, p. 1-12Article in journal (Refereed)
    Abstract [en]

    This qualitative study focuses on how knowings and learning take place in full-scale simulation training of medical and nursing students, by drawing upon actor-network theory (ANT). ANT situates materiality as a part of the social practic-es. Knowing and learning, according to ANT, are not simply cognitive or social phenomena, but are seen as emerging as effects of the relation between material assemblages and human actors being performed into being in particular locations. Data consists of observations of simulations performed by ten groups of students. The analysis focuses on the emerging knowings in the socio-material—arrangements of three locations involved in the simulation—the simulation room, the observation room and the reflection room. The findings indicate that medical knowing, affective knowing and communicative knowing are produced in different ways in the different locations and material arrangements of the simulation cycle.

  • 2.
    Bobinski, L
    et al.
    Neurokirurgisk klinik Rekonstruktionscentrum.
    Boström, Sverre
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Hillman, Jan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Theodorsson, Annette
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Postoperative pseudoaneurysm of the superficial temporal artery (S.T.A.) treated with Thrombostat® (thrombin glue) injection2004In: Acta Neurochirurgica, ISSN 0001-6268, E-ISSN 0942-0940, Vol. 146, no 9, p. 1039-1041Article in journal (Refereed)
    Abstract [en]

    Background. Pseudo-aneurysm is a rare complication of craniotomy. Blunt injury to the temporal artery region is the usual cause, but still a rare complication. Clinical presentation. A patient with subarachnoid hemorrhage was successfully treated by aneurysm clipping. The patient developed hydrocephalus, and was admitted for a shunt operation seventeen days later. The craniotomy had healed normally, but a palpable temporal lump was present in the skin incision. Intervention. The pulsating mass proved to be a postoperative aneurysm of the superficial temporal artery (S.T.A.) and was successfully occluded with 500 units Thrombostat® (thrombin glue) which was injected into the aneurysm sac using a 22-gauge needle guided by ultrasound. The permanency of the obliteration was verified by ultrasound examination.

  • 3. Bobinski, L
    et al.
    Boström, Sverre
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Zsigmond, Peter
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Theodorsson, Annette
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Leptomeningeal cyst due to vacuum extraction delivery in a twin infant2007In: Acta Neurochirurgica, ISSN 0001-6268, E-ISSN 0942-0940, Vol. 149, no 3, p. 319-323Article in journal (Refereed)
    Abstract [en]

    A rare case of a leptomeningeal cyst is reported in a twin male neonate delivered using a vacuum extractor, who presented a huge, non-pulsating, oedematous mass overlying the frontal fontanelle after birth. The mass was initially diagnosed as a cephalo haematoma. Ultrasonography indicated intracranial bleeding and a subsequent CT scan revealed an intraparenchymal bleeding above the left frontal horn, combined with a thin, left-sided, subdural haematoma and subarachnoid haemorrhage in the left Sylvian fissure. Apart from a bulging soft and round formation (2 × 2 × 3 cm) next to the anterior fontanel growing since birth, the neurological development of the infant was normal. MRI examination at the age of 7 months revealed that it consisted of a cystic mass (leptomeningeal cyst) connected to the left frontal horn, stretching right through the brain and also penetrating the dura mater. No signs of the perinatal haematomas were observed at this time. Surgical treatment, with fenestration of the cyst into the frontal horn and a watertight duraplasty with a periosteal flap and thrombin glue covered by small bone chips, was performed at 9 months of age. Due to a residual skull bone defect a second cranioplasty with autologous skull bone was performed three and half years later. During a follow-up period of 12 years the neurological and psychological development of the boy has been indistinguishable to that of his twin brother, indicating the satisfactory outcome of the treatment. © 2007 Springer-Verlag.

  • 4.
    Boström, Sverre
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Neurosurgery . Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Bobinski, L
    Zsigmond, Peter
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Neurosurgery . Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Theodorsson, Annette
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Improved brain protection at decompressive craniectomy - a new method using Palacoso (R) R-40 (methylmethacrylate)2005In: Acta Neurochirurgica, ISSN 0001-6268, E-ISSN 0942-0940, Vol. 147, no 3, p. 279-281Article in journal (Refereed)
    Abstract [en]

    A new method is described for protecting the brain after decompressive craniectomy in which a temporary methylmethacrylate flap is formed, somewhat larger than the original bone flap, thus gaining "extra" volume for the oedematous brain in which to expand. The present procedure was developed as a pan of ordinary clinical practice particularly in response to demands from the NICU staff and our colleagues at other clinics who were responsible for the care of the patient in the post NICU period. They made us keenly aware that these patients frequently lack optimal co-ordination and balance and therefore run an increased risk of trauma to the unprotected brain when failing. This prompted us to develop a method for brain protection after decompressive craniectomy aiding in the care and rehabilitation until the final installation of the patient's own bone flap can be performed.

  • 5.
    Boström, Sverre
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Bobinski, Lukas
    Zsigmond, Peter
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Nilsson, Inge
    Theodorsson, Annette
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    A new scaled microgauge for use in neurosurgery2005In: Acta Neurochirurgica, ISSN 0001-6268, E-ISSN 0942-0940, Vol. 147, no 12, p. 1281-1282Article in journal (Refereed)
    Abstract [en]

    A new scaled microgauge is described for measuring anatomical structures during microsurgery. The instrument has a tip marked in millimetres, which can be positioned in any desired angle enabling measurement in confined areas. © Springer-Verlag 2005.

  • 6.
    Boström, Sverre
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Neurosurgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Sinnescentrum, Department of Neurosurgery UHL.
    Milos, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Neurosurgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Sinnescentrum, Department of Neurosurgery UHL.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Sinnescentrum, Department of Neurosurgery UHL.
    Bobinski, Lukas
    Department of Neurosurgery, Umeå University Hospital, Umeå.
    A new microsurgical instrument - a suction tube combined with a microdissector2011In: BRITISH JOURNAL OF NEUROSURGERY, ISSN 0268-8697, Vol. 25, no 3, p. 320-321Article in journal (Refereed)
    Abstract [en]

    A microsurgical suction tube with an attached ball probe has been developed. It functions as a microdissector when the ball probe is in its extended position, creating a larger working field than an ordinary sucker. When the ball probe is in the repose position, it does not interfere with the suction capacity, and the suction tube serves as a regular sucker. By adding the properties of the microdissector to the suction tube, dissection of exquisitely fine and subtle structures, including arachnoidal membranes, is facilitated. The ball probe is easily dismantled from the suction tube and the whole instrument conveniently cleaned.

  • 7.
    Dock, Hua
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    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.
    DNA Methylation Inhibitor Zebularine Confers Stroke Protection in Ischemic Rats2015In: TRANSLATIONAL STROKE RESEARCH, ISSN 1868-4483, Vol. 6, no 4, p. 296-300Article in journal (Refereed)
    Abstract [en]

    5-Aza-deoxycytidine (5-aza-dC) confers neuroprotection in ischemic mice by inhibiting DNA methylation. Zebularine is another DNA methylation inhibitor, less toxic and more stable in aqueous solutions and, therefore more biologically suitable. We investigated Zebularines effects on brain ischemia in a rat middle cerebral artery occlusion (MCAo) model in order to elucidate its therapeutic potential. Male Wistar wild-type (WT) rats were randomly allocated to three treatment groups, vehicle, Zebularine 100 mu g, and Zebularine 500 mu g. Saline (10 mu L) or Zebularine (10 mu L) was administered intracerebroventricularly 20 min before 45-min occlusion of the middle cerebral artery. Reperfusion was allowed after 45-min occlusion, and the rats were sacrificed at 24-h reperfusion. The brains were removed, sliced, and stained with 2 % 2,3,5-triphenyltetrazolium chloride (TTC) before measuring infarct size. Zebularine (500 mu g) reduced infarct volumes significantly (p less than 0.05) by 61 % from 20.7 +/- 4.2 % in the vehicle treated to 8.1 +/- 1.6 % in the Zebularine treated. Zebularine (100 mu g) also reduced infarct volumes dramatically by 55 to 9.4 +/- 1.2 %. The mechanisms behind this neuroprotection is not yet known, but the results agree with previous studies and support the notion that Zebularine-induced inhibition of DNA methyltransferase ameliorates ischemic brain injury in rats.

  • 8.
    Gunnarsson, Thorsteinn
    et al.
    Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Linköping University, Faculty of Health Sciences.
    Theodorsson, Annette
    Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Linköping University, Faculty of Health Sciences.
    Karlsson, Per
    Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Linköping University, Faculty of Health Sciences.
    Fridriksson, Steen
    Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Linköping University, Faculty of Health Sciences.
    Boström, Sverre
    Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Linköping University, Faculty of Health Sciences.
    Persliden, Jan
    Linköping University, Department of Medicine and Care, Radio Physics. Linköping University, Faculty of Health Sciences.
    Johansson, Ingegerd
    Hillman, Jan
    Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Linköping University, Faculty of Health Sciences.
    Mobile computerized tomography scanning in the neurosurgery intensive care unit: increase in patient safety and reduction of staff workload2000In: Journal of Neurosurgery, ISSN 0022-3085, E-ISSN 1933-0693, Vol. 93, no 3, p. 432-436Article in journal (Refereed)
    Abstract [en]

    Object. Transportation of unstable neurosurgical patients involves risks that may lead to further deterioration and secondary brain injury from perturbations in physiological parameters. Mobile computerized tomography (CT) head scanning in the neurosurgery intensive care (NICU) is a new technique that minimizes the need to transport unstable patients. The authors have been using this device since June 1997 and have developed their own method of scanning such patients.

    Methods. The scanning procedure and radiation safety measures are described. The complications that occurred in 89 patients during transportation and conventional head CT scanning at the Department of Radiology were studied prospectively. These complications were compared with the ones that occurred during mobile CT scanning in 50 patients in the NICU. The duration of the procedures was recorded, and an estimation of the staff workload was made. Two patient groups, defined as high- and medium-risk cases, were studied. Medical and/or technical complications occurred during conventional CT scanning in 25% and 20% of the patients in the high- and medium-risk groups, respectively. During mobile CT scanning complications occurred in 4.3% of the high-risk group and 0% of the medium-risk group. Mobile CT scanning also took significantly less time, and the estimated personnel cost was reduced.

    Conclusions. Mobile CT scanning in the NICU is safe. It minimizes the risk of physiological deterioration and technical mishaps linked to intrahospital transport, which may aggravate secondary brain injury. The time that patients have to remain outside the controlled environment of the NICU is minimized, and the staff's workload is decreased.

  • 9.
    Hilke, Susanne
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Theodorsson, Anette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Fetissov, Serguei
    Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden .
    Åman, Katarina
    Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden .
    Holm, Lovisa
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Hökfelt, Tomas
    Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden .
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Estrogen induces a rapid increase in galanin levels in female rat hippocampal formation: possibly a nongenomic/indirect effect2005In: European Journal of Neuroscience, ISSN 0953-816X, E-ISSN 1460-9568, Vol. 21, no 8, p. 2089-2099Article in journal (Refereed)
    Abstract [en]

    Administration of 17β-estradiol to ovariectomized rats increased the concentrations of galanin-like immunoreactivity (LI) in the hippocampal formation by 215% (P < 0.001) within 1 h. An increase of 125% (P < 0.05) was observed in the same brain region in the proestrous phase of a normal estrous cycle. Tamoxifen® did not block the 17β-estradiol-induced increase in the concentration of galanin-LI but resulted in a 62% decrease in the hypothalamus within 1 h. In vivo microdialysis in the dorsal hippocampal formation showed a decrease of extracellular galanin-LI (P < 0.001) 1−2 h after treatment with 17β-estradiol, indicating a decreased release of galanin. For comparision, we studied the concentrations of neuropeptide Y, which were not influenced significantly in any of the regions studied. Taken together our results suggest that 17β-estradiol inhibits galanin release, presumably from noradrenergic nerve terminals, and primarily via a nongenomic/indirect action, not necessarily involving the classical nuclear receptors ER-α or ER-β. These rapid estrogen-induced changes in galanin release could influence transmitter signalling and plasticity in the hippocampal formation.

  • 10.
    Hilke, Susanne
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Theodorsson, Anette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Rugarn, Olof
    Hökfelt, Tomas
    Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Galanin in the hippocampal formation of female rats: effects of 17beta estradiol2005In: Neuropeptides, ISSN 0143-4179, Vol. 39, no 3, p. 253-257Article in journal (Refereed)
    Abstract [en]

    17β-Estradiol induced an increase in tissue concentrations of galanin in the hippocampal formation of ovariectomized rats. This increase was dose- and time dependent, and occurred already 60 min after steroid administration and was not blocked by Tamoxifen®. There was also an increase in galanin in the pro-estrous phase in regularly cycling rats. The estrogen-induced rapid increase may at least in part be due to decreased release of galanin as demonstrated by in vivo microdialysis studies. Thus, sex steroid hormones may influence signalling molecules in brain areas of importance for cognitive functions.

  • 11.
    Holm, Lovisa
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Hilke, Susanne
    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.
    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.
    Hokfelt, Tomas
    Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    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.
    Changes in galanin and GalR1 gene expression in discrete brain regions after transient occlusion of the middle cerebral artery in female rats2012In: Neuropeptides, ISSN 0143-4179, E-ISSN 1532-2785, Vol. 46, no 1, p. 19-27Article in journal (Refereed)
    Abstract [en]

    Injury to neurons results in upregulation of galanin in some central and peripheral systems, and it has been suggested that this neuropeptide may play a protective and trophic role, primarily mediated by galanin receptor 2 (GalR2). The objective of the present study was to investigate galanin, GalR1, GalR2 and GalR3 gene expression in the female rat brain seven days after a 60-min unilateral occlusion of the middle cerebral artery followed by reperfusion. Quantitative real-time PCR was employed in punch-biopsies from the locus coeruleus, somatosensory cortex and dorsal hippocampal formation including sham-operated rats as controls. Galanin gene expression showed a ~2.5-fold increase and GalR1 a ~1.5-fold increase in the locus coeruleus of the ischemic hemisphere compared to the control side. Furthermore, the GalR1 mRNA levels decreased by 35% in the cortex of the ischemic hemisphere. The present results indicate that a stroke-induced forebrain lesion upregulates synthesis of galanin and GalR1 in the locus coeruleus, a noradrenergic cell group projecting to many forebrain areas, including cortex and the hippocampal formation. These results support the notion that galanin may play a role in the response of the central nervous system to injury and have trophic eff ects.

  • 12.
    Holm, Lovisa
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. 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.
    Hokfelt, Tomas
    Karolinska Institute.
    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.
    Effects of intracerebroventricular galanin or a galanin receptor 2/3 agonist on the lesion induced by transient occlusion of the middle cerebral artery in female rats2011In: Neuropeptides, ISSN 0143-4179, E-ISSN 1532-2785, Vol. 45, no 1, p. 17-23Article in journal (Refereed)
    Abstract [en]

    Several studies have shown that injury to the central and peripheral nervous system can increase expression of galanin, a 29 amino acid neuropeptide. Moreover, there is evidence that galanin, especially through its galanin receptor 2 (GalR2) receptor, plays a neuroprotective role in different injury models. However, direct studies of a possible neuroprotective effect of galanin in experimental stroke models are lacking. Galanin, a GalR2/3 agonist or artificial CSF was continuously infused intracerebroventricularly (i.c.v.) in naive female rats after a 60 min transient and focal occlusion of the middle cerebral artery. The animals were sacrificed, and the ischemic lesion was visualized using 2,3,5-triphenyltetrazolium hydrochloride (TTC) staining. The lesion was 98% larger after i.c.v, administration of the GalR2/3 agonist (2.4 nmol/day) seven days after occlusion compared to artificial CSF (p = 0.023). No statistically significant differences were found after seven days in the groups treated with galanin in three different concentrations (0.24, 2.4 and 24 nmol/day; p = 0.939, 0.715 and 0.977, respectively). There was no difference in the size of the ischemic lesions measured after three days in the galanin-treated group (2.4 nmol/d) compared to artificial CSF (p = 0.925). The present results show, surprisingly, that a GalR2/3 agonist doubled the size of the ischemic lesion. Whether this effect primarily reflects the properties of the current model, species, gender and/or the mode of galanin administration, e.g. causing desensitization, or whether galanin indeed lacks neuroprotective effect of its own, remains to be corroborated.

  • 13.
    Ingberg, Edvin
    et al.
    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 Chemistry.
    Dock, Hua
    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.
    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.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Ström, Jakob O
    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. Vårdvetenskapligt Forskningscentrum/Centre for Health Sciences, Örebro University Hospital, Region Örebro Län, Örebro, Sweden / School of Health and Medical Sciences, Örebro University, Örebro, Sweden..
    Method parameters’ impact on mortality and variability in mouse stroke experiments: a meta-analysis2016In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6Article in journal (Refereed)
    Abstract [en]

    Although hundreds of promising substances have been tested in clinical trials, thrombolysis currently remains the only specifi c pharmacological treatment for ischemic stroke. Poor quality, e.g. low statistical power, in the preclinical studies has been suggested to play an important role in these failures. Therefore, it would be attractive to use animal models optimized to minimize unnecessary mortality and outcome variability, or at least to be able to power studies more exactly by predicting variability and mortality given a certain experimental setup. The possible combinations of methodological parameters are innumerous, and an experimental comparison of them all is therefore not feasible. As an alternative approach, we extracted data from 334 experimental mouse stroke articles and, using a hypothesis-driven meta-analysis, investigated the method parameters’ impact on infarct size variability and mortality. The use of Swiss and C57BL6 mice as well as permanent occlusion of the middle cerebral artery rendered the lowest variability of the infarct size while the emboli methods increased variability. The use of Swiss mice increased mortality. Our study offers guidance for researchers striving to optimize mouse stroke models.

  • 14.
    Ingberg, Edvin
    et al.
    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.
    Gudjonsdottir, Johanna
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    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.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Ström, Jakob
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. County Council Örebro, Sweden; University of Örebro, Sweden.
    Elevated body swing test after focal cerebral ischemia in rodents: methodological considerations2015In: BMC neuroscience (Online), ISSN 1471-2202, E-ISSN 1471-2202, Vol. 16, no 50Article in journal (Refereed)
    Abstract [en]

    Background: The elevated body swing test (EBST) is a behavioral test used to evaluate experimental stroke in rodents. The basic idea is that when the animal is suspended vertically by the tail, it will swing its head laterally to the left or right depending on lesion side. In a previous study from our lab using the EBST after middle cerebral artery occlusion (MCAo), rats swung contralateral to the infarct day 1 post-MCAo, but ipsilateral day 3 post-MCAo. This shift was unexpected and prompted us to perform the present study. First, the literature was systematically reviewed to elucidate whether a similar shift had been noticed before, and if consensus existed regarding swing direction. Secondly, an experiment was conducted to systematically investigate the suggested behavior. Eighty-three adult male and female Sprague-Dawley rats were subjected to MCAo or sham surgery and the EBST was performed up to 7 days after the lesion. Results: Both experimentally and through systematic literature review, the present study shows that the direction of biased swing activity in the EBST for rodents after cerebral ischemia can differ and even shift over time in some situations. The EBST curve for females was significantly different from that of males after the same occlusion time (p = 0.023). Conclusions: This study highlights the importance of adequate reporting of behavioral tests for lateralization and it is concluded that the EBST cannot be recommended as a test for motor asymmetry after MCAo in rats.

  • 15.
    Ingberg, Edvin
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Department of Clinical and Experimental Medicine, Neurosurgery. 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 O
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Methods for long-term 17β-estradiol administration to mice2012In: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, Vol. 175, no 1, p. 188-193Article in journal (Refereed)
    Abstract [en]

    Rodent models constitute a cornerstone in the elucidation of the effects and biological mechanisms of 17β-estradiol. However, a thorough assessment of the methods for long-term administration of 17β-estradiol to mice is lacking. The fact that 17β-estradiol has been demonstrated to exert different effects depending on dose emphasizes the need for validated administration regimens. Therefore, 169 female C57BL/6 mice were ovariectomized and administered 17β-estradiol using one of the two commonly used subcutaneous methods; slow-release pellets (0.18 mg, 60-day release pellets; 0.72 mg, 90-day release pellets) and silastic capsules (with/without convalescence period, silastic laboratory tubing, inner/outer diameter: 1.575/3.175 mm, filled with a 14 mm column of 36 μg 17β-estradiol/mL sesame oil), or a novel peroral method (56 μg 17β-estradiol/day/kg body weight in the hazelnut cream Nutella). Forty animals were used as ovariectomized and intact controls. Serum samples were obtained weekly for five weeks and 17β-estradiol concentrations were measured using radioimmunoassay. The peroral method resulted in steady concentrations within – except on one occasion – the physiological range and the silastic capsules produced predominantly physiological concentrations, although exceeding the range by maximum a factor three during the first three weeks. The 0.18 mg pellet yielded initial concentrations an order of magnitude higher than the physiological range, which then decreased drastically, and the 0.72 mg pellet produced between 18 and 40 times higher concentrations than the physiological range during the entire experiment. The peroral method and silastic capsules described in this article constitute reliable modes of administration of 17β-estradiol, superior to the widely used commercial pellets.

  • 16.
    Ingberg, Edvin
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry.
    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.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery. Östergötlands Läns Landsting, 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. veÖrebro University Hospital, Sweden; Unirsity of Örebro, Sweden.
    Effects of high and low 17 beta-estradiol doses on focal cerebral ischemia in rats2016In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, no 20228Article in journal (Refereed)
    Abstract [en]

    The majority of the numerous animal studies of the effects of estrogens on cerebral ischemia have reported neuroprotective results, but a few have shown increased damage. Differences in hormone administration methods, resulting in highly different 17 beta-estradiol levels, may explain the discrepancies in previously reported effects. The objective of the present study was to test the hypothesis that it is the delivered dose per se, and not the route and method of administration, that determines the effect, and that high doses are damaging while lower doses are protective. One hundred and twenty ovariectomized female Wistar rats (n = 40 per group) were randomized into three groups, subcutaneously administered different doses of 17 beta-estradiol and subjected to transient middle cerebral artery occlusion. The modified sticky tape test was performed after 24 h and the rats were subsequently sacrificed for infarct size measurements. In contrast to our hypothesis, a significant negative correlation between 17 beta-estradiol dose and infarct size was found (p = 0.018). Thus, no support was found for the hypothesis that 17 beta-estradiol can be both neuroprotective and neurotoxic merely depending on dose. In fact, on the contrary, the findings indicate that the higher the dose of 17 beta-estradiol, the smaller the infarct.

  • 17.
    Ingberg, Edvin
    et al.
    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 Chemistry.
    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.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Ström, Jakob O
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Vårdvetenskapligt Forskningscentrum/Centre for Health Sciences, Örebro University Hospital, Region Örebro Län, Örebro, Sweden / School of Health and Medical Sciences, Örebro University, Örebro, Sweden..
    Effects of high and low 17β-estradiol doses on focal cerebral ischemia in rats2016Manuscript (preprint) (Other academic)
    Abstract [en]

    The majority of the numerous animal studies of the effects of estrogens on cerebral ischemia have reported neuroprotective results, but a few have shown increased damage. Differences in hormone administration methods, resulting in highly different 17β-estradiol levels, may explain the discrepancies in previously reported effects. The objective of the present study was to test the hypothesis that it is the delivered dose per se, and not the route and method of administration, that determines the effect, and that high doses are damaging while lower doses are protective. One hundred and twenty ovariectomized female Wistar rats (n=40 per group) were randomized into three groups, subcutaneously administered different doses of 17β-estradiol and subjected to transient middle cerebral artery occlusion. The modifi ed sticky tape test was performed after 24 h and the rats were subsequently sacrifi ced for infarct size measurements. In contrast to our hypothesis, a signifi cant negative correlation between 17β-estradiol dose and infarct size was found (p=0.018). Thus, no support was found for the hypothesis that 17β-estradiol can be both neuroprotective and neurotoxic merely depending on dose. In fact, on the contrary, the fi ndings indicate that the higher the dose of 17β-estradiol, the smaller the infarct.

  • 18.
    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.

  • 19.
    Ivars, Katrin
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Nelson Follin, Nina
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, Department of Paediatrics in Linköping. Gothenburg University, Sweden.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    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.
    Mörelius, Evalotte
    Linköping University, Department of Social and Welfare Studies, Division of Nursing Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, Department of Gynaecology and Obstetrics in Linköping.
    Correction: Development of Salivary Cortisol Circadian Rhythm and Reference Intervals in Full-Term Infants2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 3, article id e0151888Article in journal (Other academic)
    Abstract [en]

    BACKGROUND:

    Cortisol concentrations in plasma display a circadian rhythm in adults and children older than one year. Earlier studies report divergent results regarding when cortisol circadian rhythm is established. The present study aims to investigate at what age infants develop a circadian rhythm, as well as the possible influences of behavioral regularity and daily life trauma on when the rhythm is established. Furthermore, we determine age-related reference intervals for cortisol concentrations in saliva during the first year of life.

    METHODS:

    130 healthy full-term infants were included in a prospective, longitudinal study with saliva sampling on two consecutive days, in the morning (07:30-09:30), noon (10:00-12:00) and evening (19:30-21:30), each month from birth until the infant was twelve months old. Information about development of behavioral regularity and potential exposure to trauma was obtained from the parents through the Baby Behavior Questionnaire and the Life Incidence of Traumatic Events checklist.

    RESULTS:

    A significant group-level circadian rhythm of salivary cortisol secretion was established at one month, and remained throughout the first year of life, although there was considerable individual variability. No correlation was found between development of cortisol circadian rhythm and the results from either the Baby Behavior Questionnaire or the Life Incidence of Traumatic Events checklist. The study presents salivary cortisol reference intervals for infants during the first twelve months of life.

    CONCLUSIONS:

    Cortisol circadian rhythm in infants is already established by one month of age, earlier than previous studies have shown. The current study also provides first year age-related reference intervals for salivary cortisol levels in healthy, full-term infants.

  • 20.
    Ivars, Katrin
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Nelson Follin, Nina
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, Department of Paediatrics in Linköping. Gothenburg University, Sweden.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    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.
    Mörelius, Evalotte
    Linköping University, Department of Social and Welfare Studies, Division of Health, Activity and Care. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, Department of Paediatrics in Linköping.
    Development of Salivary Cortisol Circadian Rhythm and Reference Intervals in Full-Term Infants2015In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, no 6, article id e0129502Article in journal (Refereed)
    Abstract [en]

    Background Cortisol concentrations in plasma display a circadian rhythm in adults and children older than one year. Earlier studies report divergent results regarding when cortisol circadian rhythm is established. The present study aims to investigate at what age infants develop a circadian rhythm, as well as the possible influences of behavioral regularity and daily life trauma on when the rhythm is established. Furthermore, we determine age-related reference intervals for cortisol concentrations in saliva during the first year of life. Methods 130 healthy full-term infants were included in a prospective, longitudinal study with saliva sampling on two consecutive days, in the morning (07:30-09:30), noon (10:00-12:00) and evening (19:30-21:30), each month from birth until the infant was twelve months old. Information about development of behavioral regularity and potential exposure to trauma was obtained from the parents through the Baby Behavior Questionnaire and the Life Incidence of Traumatic Events checklist. Results A significant group-level circadian rhythm of salivary cortisol secretion was established at one month, and remained throughout the first year of life, although there was considerable individual variability. No correlation was found between development of cortisol circadian rhythm and the results from either the Baby Behavior Questionnaire or the Life Incidence of Traumatic Events checklist. The study presents salivary cortisol reference intervals for infants during the first twelve months of life. Conclusions Cortisol circadian rhythm in infants is already established by one month of age, earlier than previous studies have shown. The current study also provides first year age-related reference intervals for salivary cortisol levels in healthy, full-term infants.

  • 21.
    Neselius, Sanna
    et al.
    Sahlgrens University Hospital, Sweden University of Gothenburg, Sweden .
    Brisby, Helena
    Sahlgrens University Hospital, Sweden University of Gothenburg, Sweden .
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Sinnescentrum, Department of Neurosurgery UHL.
    Blennow, Kaj
    Sahlgrens University Hospital, Sweden University of Gothenburg, Sweden .
    Zetterberg, Henrik
    Sahlgrens University Hospital, Sweden University of Gothenburg, Sweden .
    Marcusson, Jan
    Linköping University, Department of Clinical and Experimental Medicine, Geriatric. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Geriatric Medicine.
    CSF-Biomarkers in Olympic Boxing: Diagnosis and Effects of Repetitive Head Trauma2012In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, no 4Article in journal (Refereed)
    Abstract [en]

    Background: Sports-related head trauma is common but still there is no established laboratory test used in the diagnostics of minimal or mild traumatic brain injuries. Further the effects of recurrent head trauma on brain injury markers are unknown. The purpose of this study was to investigate the relationship between Olympic (amateur) boxing and cerebrospinal fluid (CSF) brain injury biomarkers. Methods: The study was designed as a prospective cohort study. Thirty Olympic boxers with a minimum of 45 bouts and 25 non-boxing matched controls were included in the study. CSF samples were collected by lumbar puncture 1-6 days after a bout and after a rest period for at least 14 days. The controls were tested once. Biomarkers for acute and chronic brain injury were analysed. Results: NFL (mean +/- SD, 5326 +/- 553 vs 135 +/- 51 ng/L p = 0.001), GFAP (496 +/- 238 vs 247 +/- 147 ng/L pless than0.001), T-tau (58 +/- 26 vs 49 +/- 21 ng/L pless than0.025) and S-100B (0.76 +/- 0.29 vs 0.60 +/- 0.23 ng/L p = 0.03) concentrations were significantly increased after boxing compared to controls. NFL (402 +/- 434 ng/L p = 0.004) and GFAP (369 +/- 113 ng/L p = 0.001) concentrations remained elevated after the rest period. Conclusion: Increased CSF levels of T-tau, NFL, GFAP, and S-100B in greater than80% of the boxers demonstrate that both the acute and the cumulative effect of head trauma in Olympic boxing may induce CSF biomarker changes that suggest minor central nervous injuries. The lack of normalization of NFL and GFAP after the rest period in a subgroup of boxers may indicate ongoing degeneration. The recurrent head trauma in boxing may be associated with increased risk of chronic traumatic brain injury.

  • 22.
    Paues, Jakob
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Infectious Diseases.
    Ström, Jakob
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Eriksson, Lars
    Linköping University, Department of Clinical and Experimental Medicine, Infectious Diseases. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Infectious Diseases.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Neurosurgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Tuberculous meningitis with positive cell-count in lumbar puncture CSF though negative cell-count from ventricular drainage CSF2011In: Journal of Infection, ISSN 0163-4453, E-ISSN 1532-2742, Vol. 62, no 5, p. 404-405Article in journal (Other academic)
  • 23.
    Rugarn, O
    et al.
    Fac Hlth Sci, Dept Obstet & Gynaecol, Linkoping, Sweden Fac Hlth Sci, Dept Neurosurg, Linkoping, Sweden.
    Theodorsson, Annette
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Hammar, Mats
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Obstetrics and gynecology . Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Department of Gynecology and Obstetrics in Linköping.
    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.
    Effects of estradiol on regional concentrations of galanin in the rat brain1999In: Brain Research, ISSN 0006-8993, E-ISSN 1872-6240, Vol. 848, no 1-2, p. P323-Conference paper (Other academic)
  • 24.
    Rugarn, Olof
    et al.
    Linköping University, Department of Molecular and Clinical Medicine, Obstetrics and gynecology. Linköping University, Faculty of Health Sciences.
    Hammar, Mats
    Linköping University, Department of Clinical and Experimental Medicine, Obstetrics and gynecology. Linköping University, Faculty of Health Sciences.
    Theodorsson, Annette
    Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Linköping University, Faculty of Health Sciences.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Stenfors, Carina
    Department of Laboratory Medicine, Karolinska Hospital, Stockholm, Sweden.
    Sex differences in neuropeptide distribution in the rat brain1999In: Peptides, ISSN 0196-9781, E-ISSN 1873-5169, Vol. 20, no 1, p. 81-86Article in journal (Refereed)
    Abstract [en]

    We have investigated possible sex differences in the regional concentrations of neuropeptides in the rat brain. Immunoreactive neurotensin (NT), neurokinin A (NKA), galanin (GAL), calcitonin gene-related peptide (CGRP), substance P (SP) and neuropeptide Y (NPY) were measured by radioimmunoassay in frontal cortex, occipital cortex, hippocampus, striatum, hypothalamus and pituitary in male and female pre- and postpubertal rats. Sex differences were found for NPY (p < 0.001), NT (p < 0.01) and GAL (p < 0.05), in particular in hippocampus, striatum, hypothalamus and pituitary, but not for CGRP, SP and NKA. Results from analysis of neuropeptides in one sex may not be entirely applicable to the other.

  • 25.
    Rugarn, Olof
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Obstetrics and gynecology. Linköping University, Faculty of Health Sciences.
    Theodorsson, Annette
    Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Linköping University, Faculty of Health Sciences.
    Hammar, Mats
    Linköping University, Department of Clinical and Experimental Medicine, Obstetrics and gynecology. Linköping University, Faculty of Health Sciences.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Effects of estradiol, progesterone, and norethisterone on regional concentrations of galanin in the rat brain1999In: Peptides, ISSN 0196-9781, E-ISSN 1873-5169, Vol. 20, no 6, p. 743-748Article in journal (Refereed)
    Abstract [en]

    Concentrations of immunoreactive galanin were compared in eight gross brain regions of ovariectomized female rats treated with either estradiol, estradiol + progesterone, estradiol + norethisterone, or placebo. Higher concentrations with estradiol treatment compared with placebo were found in the pituitary (357%), frontal cortex (162%), occipital cortex (174%), hippocampus (170%), and median eminence (202%). A more profound difference with addition of progesterone or norethisterone was seen in the pituitary (529% and 467%, respectively). Sex steroids, particularly estradiol, modulate galanin concentrations not only in reproductive, but also in nonreproductive, brain regions.

  • 26.
    Sinkvist, David
    et al.
    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 Central Östergötland, Primary Health Care in Central County.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Ledin, Torbjörn
    Linköping University, Department of Clinical and Experimental Medicine, Division of Speech language pathology, Audiology and Otorhinolaryngology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Otorhinolaryngology in Linköping.
    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.
    Five Year Data and Results of Continuous Quality Improvement Using SKURT2017In: Educational Research Applications, E-ISSN 2575-7032, Vol. 2017, no 05, article id ERCA-125Article in journal (Refereed)
    Abstract [en]

    Student rating of teaching isessentialfor attaining and maintaining higheducational quality.A quality improvement system, SKURT,based on digital online weekly combined quantitative, ten-graded scale, and qualitative, open-ended free text, group feedback from medical students was developed. Students rated all educational, non-clerkship, items throughout the entire medical program, spanning eleven terms. The results were semi-publicly available for students and faculty at a Swedish university. This study describes datafrom five-year use of the system,focusing on how the use of SKURT influenced educational items found to be in the most substantial need for improvements.

    Statistically but hardly practically significant improvement in average feedback grade was found during the observation period (average 7.07 in 2009 to 7.24 in 2013 (p<0.001)).The medical program was already in 2007recognized ascenter of excellent quality in higher education. When analyzing the 18 lectures with lowest outcome in the spring 2009 compared to the fall 2013, five were discontinued. The remaining 13 lectures improved significantly (p<0.001) 116% from 2.94 (SD 0.92) to 6.34 (SD 2.58). 

    A weekly group feedback system employing the principles used in SKURTis useful forimproving the quality of medical education particularlyby improvingthe items with the lowest ratings.

  • 27.
    Sinkvist, David
    et al.
    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 Central Östergötland, Primary Health Care in Central County.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Ledin, Torbjörn
    Linköping University, Department of Clinical and Experimental Medicine, Division of Speech language pathology, Audiology and Otorhinolaryngology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Otorhinolaryngology in Linköping.
    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.
    SKURT: Quality Improvement System with Comprehensive Weekly Digital Student Group Feedback2017In: Educational Research Applications, E-ISSN 2575-7032, Vol. 2017, no 5, article id RCA-124Article in journal (Refereed)
    Abstract [en]

    Students’ role in evaluation and rating of teachers and education has been extensively researched for nearly a century. Applied worldwide, students’ ratings account for the majority of the available data.We created a new quality improvement system, SKURT, using digital online weekly combined quantitative, ten-graded scale, and qualitative, open-ended free text, group feedback from medical students. Students rated all educational, non-clerkship, items throughout the entire medical program, spanning eleven terms. The rating process is since 2008 an integral part of a medical program at a Swedish university. The results are, after a screening process, semi-publicly available on-demand, for students and faculty, creating a feedback loop enabling continuous improvement of quality.A thorough literature search of students rating of teaching found no other corresponding weekly group rating system spanning all educational items. Quality improvement systems based on similar principles as SKURT can uncover problem areas that are difficult to find using other rating systems and has the potential to circumvent several biases, risks and shortcomings of traditional rating systems in current use.

  • 28.
    Ström, Jakob
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Boström, Sverre
    Linköping University, Department of Clinical and Experimental Medicine, Neurosurgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Bobinski, L.
    Umeå University, Sweden.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Department of Clinical and Experimental Medicine, Neurosurgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Low-grade infection complicating silastic dural substitute 32 years post-operatively2011In: Brain Injury, ISSN 0269-9052, E-ISSN 1362-301X, Vol. 25, no 2, p. 250-254Article in journal (Refereed)
    Abstract [en]

    Background: A complication of a silastic dural substitute is described, which appeared after 32 years-by far the longest latency period reported in the literature. Methods: Case report and literature review. Results: In 1971, a 20-year old woman suffered from an acute subdural haematoma and a temporal cerebral contusion due to a motorbike accident. She underwent an operation with evacuation of these and the dura was mended with a silastic duraplasty. Thirty-two years later she deteriorated with increased memory problems and dysphasia. CT revealed an expanding haemorrhagic mass around the previous duraplasty, which demanded surgery with removal of the silastic dural implant and evacuation of the haemorrhagic mass. Although the haemorrhagic mass enveloped the silastic implant, a contribution of the acrylate flap cannot be ruled out. Bacteriological cultures revealed Acinetobacter spp. in the CSF. Adequate post-operative antibiotic treatment was administered. The patient slowly improved, but the complication represented a major setback in her long-term cognitive and communicative functions. Conclusions: This case widens the previously reported time-frame of late complications by 60%, from 20 to 32 years, and will hopefully serve to increase the awareness of late infections and haemorrhages induced by silastic dural implants, thereby improving diagnosis and treatment in future cases.

  • 29.
    Ström, Jakob
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Ingberg, Edvin
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Department of Clinical and Experimental Medicine, Neurosurgery. 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.
    Method parameters’ impact on mortality and variability in rat stroke experiments: a meta-analysis2013In: BMC neuroscience (Online), ISSN 1471-2202, E-ISSN 1471-2202, Vol. 14, no 41Article in journal (Refereed)
    Abstract [en]

    Background

    Even though more than 600 stroke treatments have been shown effective in preclinical studies, clinically proven treatment alternatives for cerebral infarction remain scarce. Amongst the reasons for the discrepancy may be methodological shortcomings, such as high mortality and outcome variability, in the preclinical studies. A common approach in animal stroke experiments is that A) focal cerebral ischemia is inflicted, B) some type of treatment is administered and C) the infarct sizes are assessed. However, within this paradigm, the researcher has to make numerous methodological decisions, including choosing rat strain and type of surgical procedure. Even though a few studies have attempted to address the questions experimentally, a lack of consensus regarding the optimal methodology remains.

    Methods

    We therefore meta-analyzed data from 502 control groups described in 346 articles to find out how rat strain, procedure for causing focal cerebral ischemia and the type of filament coating affected mortality and infarct size variability.

    Results

    The Wistar strain and intraluminal filament procedure using a silicone coated filament was found optimal in lowering infarct size variability. The direct and endothelin methods rendered lower mortality rate, whereas the embolus method increased it compared to the filament method.

    Conclusions

    The current article provides means for researchers to adjust their middle cerebral artery occlusion (MCAo) protocols to minimize infarct size variability and mortality.

  • 30.
    Ström, Jakob
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Ingberg, Edvin
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuroscience. Linköping University, Faculty of Health Sciences.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuroscience. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Effects of high and low 17 beta-estradiol doses on focal cerebral ischemia: negative results2013In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 3Article in journal (Refereed)
    Abstract [en]

    The reasons why some animal studies indicate that estrogens increase focal cerebral ischemic damage while others show estrogen-induced neuroprotection has hitherto not been fully elucidated. Recent evidence indicates that discrepancies in hormone administration paradigms, resulting in highly different serum hormone concentrations, may account for the dichotomy. The current study aimed to test this hypothesis. Sixty ovariectomized female rats were randomized into three groups differing in 17 beta-estradiol regimens, and transient focal cerebral ischemia was subsequently induced. All animals were subjected to a small functional testing battery, and three days after MCAo they were sacrificed for infarct size assessment. Infarct sizes did not differ between groups, however clear discrepancies were seen in body weight and feeding behavior. In comparison to sham-operated animals, ovariectomized rats rapidly increased in body weight, whereas the opposite was seen in rats receiving 17beta-estradiol. The weight gain in the ovariectomized rats was paralleled by an increased food intake.

  • 31.
    Ström, Jakob
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Ingberg, Edvin
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. 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, Center for Diagnostics, 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, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Effects of high and low 17β-estradiol doses on cerebral ischemiaManuscript (preprint) (Other academic)
    Abstract [en]

    INTRODUCTION: Estrogens’ effects on cerebral ischemia have during the last two decades been the subject of intense research efforts. Notwithstanding this, the reasons that some studies indicate that estrogens are damaging while others show estrogen-induced neuroprotection has hitherto not been fully elucidated. Recent evidence indicates that discrepancies in hormone administration paradigms, resulting in highly different serum hormone concentrations, may account for this dichotomy. The current study was designed to test this  ypothesis.

    METHODS: Sixty ovariectomized female rats were randomized into three groups differing in subsequent 17β-estradiol regimen (vehicle, low dose and high dose respectively). Following two weeks of treatment, focal cerebral ischemia was induced via an intraluminal filament middle cerebral artery occlusion (MCAo) method. All animals were subjected to a small functional testing battery, and three days after MCAo they were sacrificed for infarct size assessment.

    RESULTS AND DISCUSSION: The hormone administration regimens significantly affected animal weights and feeding behavior, but infarct sizes did not differ between groups. Further, random intra-group variations in infarct size were too large to allow negative conclusions to be drawn. The large variation was possibly a consequence of too large occluding filament diameter in combination with that the animals were allowed to wake up during ongoing MCAo. After correcting the large variation, the hypothesis needs to be addressed anew.

  • 32.
    Ström, Jakob O
    et al.
    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.
    Ingberg, Edvin
    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.
    Druvefors, Emma
    Ryhov County Hospital, County Council of Jönköping, Sweden.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Department of Clinical and Experimental Medicine, Neurosurgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry. 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.
    The female menstrual cycle does not influence testosterone concentrations in male partners2012In: Journal of Negative Results in Biomedicine, ISSN 1477-5751, E-ISSN 1477-5751, Vol. 11, no 1Article in journal (Refereed)
    Abstract [en]

    Background

    The time of ovulation has since long been believed to be concealed to male heterosexual partners. Recent studies have, however, called for revision of this notion. For example, male testosterone concentrations have been shown to increase in response to olfactory ovulation cues, which could be biologically relevant by increasing sexual drive and aggressiveness. However, this phenomenon has not previously been investigated in real-life human settings. We therefore thought it of interest to test the hypothesis that males' salivary testosterone concentrations are influenced by phases of their female partners' menstrual cycle; expecting a testosterone peak at ovulation.

    Methods

    Thirty young, healthy, heterosexual couples were recruited. During the course of 30-40 days, the women registered menses and ovulation, while the men registered sexual activity, physical exercise, alcohol intake and illness (confounders), and obtained daily saliva samples for testosterone measurements. All data, including the registered confounders, were subjected to multiple regression analysis.

    Results

    In contrast to the hypothesis, the ovulation did not affect the testosterone levels, and the resulting testosterone profile during the menstrual cycle was on the average flat. The specific main hypothesis, that male testosterone levels on the day of ovulation would be higher than day 4 of the cycle, was clearly contradicted by a type II error(β)-analysis (< 14.3% difference in normalized testosterone concentration; β = 0.05).

    Conclusions

    Even though an ovulation-related salivary testosterone peak was observed in individual cases, no significant effect was found on a group level.

  • 33.
    Ström, Jakob O
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, 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.
    Ingberg, Edvin
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Isaksson, Ida-Maria
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. 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, Center for Diagnostics, Department of Clinical Chemistry.
    Ovariectomy and 17β-estradiol replacement in rats and mice: a visual demonstration2012In: Journal of Visualized Experiments, ISSN 1940-087X, E-ISSN 1940-087X, no 64, p. 4013-Article in journal (Refereed)
    Abstract [en]

    Estrogens are a family of female sexual hormones with an exceptionally wide spectrum of effects. When rats and mice are used in estrogen research they are commonly ovariectomized in order to ablate the rapidly cycling hormone production, replacing the 17β-estradiol exogenously. There is, however, lack of consensus regarding how the hormone should be administered to obtain physiological serum concentrations This is crucial since the 17β-estradiol level/administration method profoundly influences the experimental results1-3. We have in a series of studies characterized the different modes of 17β-estradiol administration, finding that subcutaneous silastic capsules and per-oral nut-cream Nutella are superior to commercially available slow-release pellets (produced by the company Innovative Research of America) and daily injections in terms of producing physiological serum concentrations of 17β-estradiol4-6. Amongst the advantages of the nut-cream method, that previously has been used for buprenorphine administration7, is that when used for estrogen administration it resembles peroral hormone replacement therapy and is non-invasive. The subcutaneous silastic capsules are convenient and produce the most stable serum concentrations. This video article contains step-by-step demonstrations of ovariectomy and 17β-estradiol hormone replacement by silastic capsules and peroral Nutella in rats and mice, followed by a discussion of important aspects of the administration procedures.

  • 34.
    Ström, Jakob O
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, 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, 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.
    Dose-related neuroprotective versus neurodamaging effects of estrogens in rat cerebral ischemia: a systematic analysis2009In: Journal of Cerebral Blood Flow and Metabolism, ISSN 0271-678X, E-ISSN 1559-7016, Vol. 29, no 8, p. 1359-1372Article, review/survey (Refereed)
    Abstract [en]

    Numerous studies of the effects of estrogens for stroke prevention have yielded conflicting results in human and animal studies alike. We present a systematical analysis of study design and methodological differences between 66 studies where estrogens impact on ischemic brain damage in rat models has been investigated, providing evidence that the differences in results may be explained by high estrogen doses produced by slow-release pellets. These pellets have been used in all studies showing increased neurologic damage because of estrogens. Our data indicate that the increased neurologic damage is related to the pellets plasma concentration profile with an early, prolonged, supraphysiological peak. Neither the method of inducing the ischemic brain lesions, the choice of variables for measuring outcome, the measured plasma concentrations of estrogens at the time of ischemia nor rat population attributes (sex, strain, age, and diseases) are factors contributing to the discrepancies in results. This suggests that the effects of estrogens for stroke prevention are concentration related with a complex dose-response curve, and underscores the importance of carefully validating the experimental methods used. Future studies of hormone-replacement therapy in women may have to take dosage and administration regimens into account.

  • 35.
    Ström, Jakob O
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Department of Clinical and Experimental Medicine, Neurosurgery. 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.
    Hormesis and Female Sex Hormones2011In: Pharmaceuticals, ISSN 1424-8247, E-ISSN 1424-8247, Vol. 4, p. 726-740Article in journal (Refereed)
    Abstract [en]

    Hormone replacement after menopause has in recent years been the subject of intense scientific debate and public interest and has sparked intense research efforts into the biological effects of estrogens and progestagens. However, there are reasons to believe that the doses used and plasma concentrations produced in a large number of studies casts doubt on important aspects of their validity. The concept of hormesis states that a substance can have diametrically different effects depending on the concentration. Even though estrogens and progestagens have proven prone to this kind of dose-response relation in a multitude of studies, the phenomenon remains clearly underappreciated as exemplified by the fact that it is common practice to only use one hormone dose in animal experiments. If care is not taken to adjust the concentrations of estrogens and progestagens to relevant biological conditions, the significance of the results may be questionable. Our aim is to review examples of female sexual steroids demonstrating bidirectional dose-response relations and to discuss this in the perspective of hormesis. Some examples are highlighted in detail, including the effects on cerebral ischemia, inflammation, cardiovascular diseases and anxiety. Hopefully, better understanding of the hormesis phenomenon may result in improved future designs of studies of female sexual steroids.

  • 36.
    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.

  • 37.
    Ström, Jakob O
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. 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.
    Holm, Lovisa
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Department of Clinical and Experimental Medicine, Neurosurgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Different methods for administering 17 beta-estradiol to ovariectomized rats result in opposite effects on ischemic brain damage2010In: BMC neuroscience (Online), ISSN 1471-2202, E-ISSN 1471-2202, Vol. 11, p. 39-Article in journal (Refereed)
    Abstract [en]

    Background: Numerous stroke studies have controversially shown estrogens to be either neuroprotective or neurodamaging. The discordant results observed in rat brain ischemia models may be a consequence of discrepancies in estrogen administration modes resulting in plasma concentration profiles far from those intended. To test this hypothesis we reproduced in detail and extended an earlier study from our lab using a different mode of 17 beta-estradiol administration; home-made silastic capsules instead of commercial slow-release 17 beta-estradiol pellets. Four groups of female rats (n = 12) were ovariectomized and administered 17 beta-estradiol or placebo via silastic capsules. All animals underwent MCAo fourteen days after ovariectomy and were sacrificed three days later.

    Results: In contrast to our earlier results using the commercial pellets, the group receiving 17 beta-estradiol during the entire experiment had significantly smaller lesions than the group receiving placebo (mean +/- SEM: 3.85 +/- 0.70% versus 7.15 +/- 0.27% of total slice area, respectively; p = 0.015). No significant neuroprotection was found when the 17 beta-estradiol was administered only during the two weeks before or the three days immediately after MCAo.

    Conclusions: The results indicate that different estrogen treatment regimens result in diametrically different effects on cerebral ischemia. Thus the effects of estrogens on ischemic damage seem to be concentration-related, with a biphasic, or even more complex, dose-response relation. These findings have implications for the design of animal experiments and also have a bearing on the estrogen doses used for peri-menopausal hormone replacement therapy.

  • 38.
    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.

  • 39.
    Ström, Jakob
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, 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, 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, Center for Diagnostics, Department of Clinical Chemistry.
    Mechanisms of estrogens' dose-dependent neuroprotective and neurodamaging effects in experimental models of cerebral ischemia2011In: International Journal of Molecular Sciences, ISSN 1422-0067, E-ISSN 1422-0067, Vol. 12, no 3, p. 1533-1562Article, review/survey (Refereed)
    Abstract [en]

    Ever since the hypothesis was put forward that estrogens could protect against cerebral ischemia, numerous studies have investigated the mechanisms of their effects. Despite initial studies showing ameliorating effects, later trials in both humans and animals have yielded contrasting results regarding the fundamental issue of whether estrogens are neuroprotective or neurodamaging. Therefore, investigations of the possible mechanisms of estrogen actions in brain ischemia have been difficult to assess. A recently published systematic review from our laboratory indicates that the dichotomy in experimental rat studies may be caused by the use of insufficiently validated estrogen administration methods resulting in serum hormone concentrations far from those intended, and that physiological estrogen concentrations are neuroprotective while supraphysiological concentrations augment the damage from cerebral ischemia. This evidence offers a new perspective on the mechanisms of estrogens actions in cerebral ischemia, and also has a direct bearing on the hormone replacement therapy debate. Estrogens affect their target organs by several different pathways and receptors, and the mechanisms proposed for their effects on stroke probably prevail in different concentration ranges. In the current article, previously suggested neuroprotective and neurodamaging mechanisms are reviewed in a hormone concentration perspective in an effort to provide a mechanistic framework for the dose-dependent paradoxical effects of estrogens in stroke. It is concluded that five protective mechanisms, namely decreased apoptosis, growth factor regulation, vascular modulation, indirect antioxidant properties and decreased inflammation, and the proposed damaging mechanism of increased inflammation, are currently supported by experiments performed in optimal biological settings.

  • 40.
    Ström, Jakob
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, 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, Sinnescentrum, 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 Diagnostics, Department of Clinical Chemistry.
    Research design and statistical power when publishing "negative findings"2011In: The Journal of Neuroscience, ISSN 0270-6474Article, book review (Other academic)
  • 41.
    Sturnegk, Patrik
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Mellergård, Pekka
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Yonas, H
    Theodorsson, Annette
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Hillman, Jan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Potential use of quantitative bedside CBF monitoring (Xe-CT) for decision making in neurosurgical intensive care2007In: British Journal of Neurosurgery, ISSN 0268-8697, E-ISSN 1360-046X, Vol. 21, no 4, p. 332-339Article in journal (Refereed)
    Abstract [en]

    During a 3-year period, mobile xenon-computerized tomography (Xe-CT) for bedside quantitative assessment of cerebral blood flow was used as an integrated tool for decision making during the care of complicated patients in our neurosurgical intensive care units (NSICU), in an attempt to make a preliminary evaluation regarding the usefulness of this method in routine work in the neurosurgical intensive care. With approximately 200 studies involving 75 patients, we identified six different categories where the use of bedside Xe-CT significantly influenced (or, with more experience, could have influenced) the decision making, or facilitated the handling of patients. These categories included identification of problems not apparent from other types of monitoring, avoidance of adverse effects from treatment, titration of standard treatments, evaluation of the vascular resistance reserve, assessment of adequate perfusion pressure and better utilization of resources from access to the bedside cerebral blood flow (CBF) technology. We conclude that quantitative bedside measurements of CBF could be an important addition to the diagnostic and monitoring arsenal of NSICU-tools. © The Neurosurgical Foundation.

  • 42.
    Szabó, Zoltán
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Harangi, Márta
    Nylander, Eva
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Ljungman, Anders
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Ahn, Henrik
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Davidsson, Bo
    Linköping University, Department of Behavioural Sciences and Learning.
    How students perceive problem-based learning (PBL) group tutorials at a Swedish Medical College2015In: Med Ed Publish, ISSN 2312-7996, Vol. 6, no 17Article in journal (Refereed)
    Abstract [en]

    Introduction: student perception of problem-based learning (PBL) group tutorials was investigated at a Swedish University Medical College 27 years after the introduction of PBL into the curriculum.

    Methods: a survey questionnaire comprising 43 questions answered on a Likert-type scale, together with one open question was used. The questionnaire was distributed to all 821 students taking part in the Linköping University medical program at the beginning of the Spring Term 2013. The results were subjected to explorative factor analysis, descriptive statistics and ANOVA. Responses to the open question where analyzed qualitatively by categorization.

    Results: 84 per cent of the 821 students completed the survey. Four factors describing student perception were identified: 1) PBL as a method of learning; 2) the tutor’s role; 3) PBL, stress and feelings of insecurity; and 4) traditional teaching methods within the PBL curriculum. The Cronbach´s alpha value was 0,788 overall. Two hundred and seventy-six students answered the open question declaring that they would appreciate more precise aims and objectives, smaller tutorial groups, and more formal lectures.

    Conclusions: the results of this study on PBL group tutorials, as seen from the student’s perspective, stress the importance of tutorial quality, tutor competence, tutorial group size and the quality and aims of the curriculum. Too much emphasis on the teacher’s research merits against the educational ones, and the inability to adapt to the needs and wishes of new generations of students seems a probable cause for the erosion of PBL.

  • 43.
    Szabó, Zoltán
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Harangi, Márta
    Linköping, Sweden.
    Nylander, Eva
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Davidson, Bo
    Linköping University, Department of Behavioural Sciences and Learning, Education and Sociology. Linköping University, Faculty of Arts and Sciences.
    Problem-based learning (PBL): tutor perception of group work and learning2014In: MedEdPublish, ISSN 2312-7996, Vol. 3, no 46, p. 1-11Article in journal (Refereed)
    Abstract [en]

    Introduction: This paper reports a survey on how PBL is perceived by tutors. A questionnaire including 45 questions answered on a Likert-type scale, and an open question was constructed. The aim was to identify factors that tutors believe promote or impede student learning. All faculty tutors (116) teaching five different student semester cohorts at our medical college during the Spring Term of 2013 were included. Seventy-four tutors responded (64%). Methods:Descriptive statistics, explorative factor analysis.Results:Factor analysis identified five factors which explained 52 % of the variation. These factors were: PBL as a pedagogic method; tutoring problem analysis in the group; barriers to student learning; the tutor ́s role in the group; and the relationship betweentheory and practice. The model as a whole showed high reliability (Chrombach ́s alpha = 0,81). When responding to the open question, the tutors suggested organizational changes, improvement in tutor competence, clear goals in the curriculum, and smaller tutorial groups/miscellaneous. Conclusions:The tutors’ approach adhered to classical PBL methodology, and they considered it to be a good instrument for student learning. The tutorial group was seen as promoting learning. Problems related to group dynamics and tutor competence were considered a hindrance to learning.

  • 44.
    Söderlind, Kristina
    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.
    Theodorsson, Annette
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of clinical chemistry. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Hälsoekonomi på liv och död2006In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 103, p. 901-901Article in journal (Other academic)
    Abstract [sv]

      

  • 45.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Estrogen-inducible neuropeptides in the rat brain: role in focal ischemic lesions2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Sex steroids in general and estrogens in particular – in addition to their effects on the reproductive organs – affect a large number of crucial bodily functions, including “higher” brain functions.

    Neuropeptides constitute the phylogenetically oldest neurotransmitter system and are currently thought to act mainly during stress, disease or injury. The concentration of galanin is i.a. up-regulated by injury to the nervous system and by estrogen.

    The main focus of the present thesis was to investigate whether the reported neuroprotective effect of 17β-estradiol in experimental animal stroke models is partially mediated through its effects on galanin and if galanin per se exerts neuroprotective effects in stroke.

    An exploratory study of the effects of sex steroid concentrations due to gender and pubertal development showed differences in concentrations of i.a. the neuropeptides galanin and neuropeptide Y also in brain regions of female rats important for higher brain functions, including hippocampus and cortex, brain regions not directly involved in reproduction. Puberty brings about changes in several hormonal mechanisms, and our studies showed that the major effect on the concentrations of galanin in various brain regions of ovariectomized (ovx) rats, was brought about by 17β-estradiol.

    The pathophysiological mechanisms involved in thrombolysis – the current treatment of choice in human stroke – attempts the re-establishment of perfusion (reperfusion) to the lesioned area of the brain. This prompted us to develop a reperfusion stroke model in rats designed to be mild, focal and transient, allowing long-term observation periods of animals thriving well postoperatively. Mortality and morbidity during and after the middle cerebral artery (MCA) occlusion are important confounding factors crucial for the results. Changing anaesthesia from intraperitoneally administered chloral hydrate to isofl urane inhalation anaesthesia using endotracheal intubation and controlled ventilation markedly reduced the mortality rate from 25% to 10.6%, which was even further reduced down to 2.7 % by successively improved surgical skills.

    Contrary to our initial hypothesis, long-term 17β-estradiol treatment resulted in larger ischemic lesions in our stroke model compared to control treatment. After 3 days the cerebral ischemic lesion area was doubled after 17β-estradiol treatment in rats subjected to 60 min microclip occlusion of the MCA followed by reperfusion. A similar, but not statistically signifi cant difference was found after 7 and 14 days. Three groups studying different types of experimental animal stroke and different doses of 17β-estradiol treatment have recently also demonstrated lack of neuroprotection by 17β-estradiol treatment. Furthermore, large epidemiological clinical studies have recently also reported an increased risk and poorer outcome in postmenopausal women subjected to hormone replacement therapy.

    The concentrations of galanin-like immunoreactivity in extracts of punch biopsies from the penumbra area after transient MCA occlusion were found unchanged, but were decreased (p=0.015) in the apparently undamaged ipsilateral hippocampus. Galanin administered by continuous intracerebroventricular infusion (2.4 nmol/day) resulted in a 30% larger ischemic lesion compared to controls, measured 7 days after the MCA occlusion. Taken together, these results indicate that galanin in the brain is primarily a factor reacting to ischemic injury rather than a neuroprotective factor in its own right.

    Very limited information is available about the steady state serum concentrations of 17β-estradiol in response to different modes of administration to rats for days and weeks. The need for this information has become especially apparent during recent years due to the observable dichotomy of estrogens effects – neuroprotective or not – in the various animal models of brain ischemia reported in the current scientific literature. The cause of this dichotomy is likely to be found in the experimental setup, including the mode of administration of 17β-estradiol. Delayed steady state of serum 17β-estradiol concentrations were found when comparing two common modes of exogenous administration of 17β-estradiol – slow-release osmotic pumps vs. daily subcutaneously injections of 17β-estradiol solved in sesame oil – to ovx rats during 2 times 6 weeks crossover treatment. Steady state was reached at week 4 in the daily injections group compared to at week 6 in the slow release osmotic pumps group. Once steady state was reached, the concentration was the same in both groups for the reminder of the experiment (in total 12 weeks).

    List of papers
    1. Sex differences in neuropeptide distribution in the rat brain
    Open this publication in new window or tab >>Sex differences in neuropeptide distribution in the rat brain
    Show others...
    1999 (English)In: Peptides, ISSN 0196-9781, E-ISSN 1873-5169, Vol. 20, no 1, p. 81-86Article in journal (Refereed) Published
    Abstract [en]

    We have investigated possible sex differences in the regional concentrations of neuropeptides in the rat brain. Immunoreactive neurotensin (NT), neurokinin A (NKA), galanin (GAL), calcitonin gene-related peptide (CGRP), substance P (SP) and neuropeptide Y (NPY) were measured by radioimmunoassay in frontal cortex, occipital cortex, hippocampus, striatum, hypothalamus and pituitary in male and female pre- and postpubertal rats. Sex differences were found for NPY (p < 0.001), NT (p < 0.01) and GAL (p < 0.05), in particular in hippocampus, striatum, hypothalamus and pituitary, but not for CGRP, SP and NKA. Results from analysis of neuropeptides in one sex may not be entirely applicable to the other.

    Keywords
    Sex differences, Neuropeptide Y, Neurotensin, Galanin, Hippocampus, Pituitary, Frontal cortex, Puberty
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-13441 (URN)10.1016/S0196-9781(98)00139-9 (DOI)
    Available from: 2005-11-11 Created: 2005-11-11 Last updated: 2017-12-13Bibliographically approved
    2. Effects of estradiol, progesterone, and norethisterone on regional concentrations of galanin in the rat brain
    Open this publication in new window or tab >>Effects of estradiol, progesterone, and norethisterone on regional concentrations of galanin in the rat brain
    1999 (English)In: Peptides, ISSN 0196-9781, E-ISSN 1873-5169, Vol. 20, no 6, p. 743-748Article in journal (Refereed) Published
    Abstract [en]

    Concentrations of immunoreactive galanin were compared in eight gross brain regions of ovariectomized female rats treated with either estradiol, estradiol + progesterone, estradiol + norethisterone, or placebo. Higher concentrations with estradiol treatment compared with placebo were found in the pituitary (357%), frontal cortex (162%), occipital cortex (174%), hippocampus (170%), and median eminence (202%). A more profound difference with addition of progesterone or norethisterone was seen in the pituitary (529% and 467%, respectively). Sex steroids, particularly estradiol, modulate galanin concentrations not only in reproductive, but also in nonreproductive, brain regions.

    Keywords
    Galanin, Estradiol, Progesterone, Norethisterone, Hippocampus, Pituitary, Frontal cortex
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-13442 (URN)10.1016/S0196-9781(99)00057-1 (DOI)
    Available from: 2005-11-11 Created: 2005-11-11 Last updated: 2017-12-13Bibliographically approved
    3. Modern anesthesia and peroperative monitoring methods reduce per- and postoperative mortality during transient occlusion of the middle cerebral artery in rats
    Open this publication in new window or tab >>Modern anesthesia and peroperative monitoring methods reduce per- and postoperative mortality during transient occlusion of the middle cerebral artery in rats
    2005 (English)In: Brain Research Protocols, ISSN 1385-299X, E-ISSN 1872-809X, Vol. 14, no 3, p. 181-190Article in journal (Refereed) Published
    Abstract [en]

    Mortality and morbidity during and after occlusion of the middle cerebral artery in rats are important confounding factors which may be minimized by improved anesthesia and peroperative monitoring techniques. We describe state of the art techniques for inducing anesthesia, endotracheal intubation, ventilation and monitoring peroperatively in this context.

    Introducing the subtemporal approach of Tamura et al. in our laboratory 5 years ago, we experienced 25% peroperative and 24 h postoperative rat mortality when performing temporary clipping of the middle cerebral artery. This prompted us to abandon intraperitoneal anesthesia by chloral hydrate and ventilation by tracheotomy in favor of endotracheal intubation and isoflurane anesthesia (1% isoflurane in 30%:70% O2/N2O). These anesthetic techniques in combination with improved surgical skills have reduced our initial 25% peroperative- and 24 h postoperative mortality to 2.7% (1.8% peroperatively and 0.9% 24 h postoperatively). Furthermore, the following 14 days postoperative mortality rate was 1.8%. A total number of 203 rats have been operated with this method in different studies where a focal reperfusion stroke model combined with extended periods of observations were the cornerstone.

    Keywords
    Cerebral ischemia; Focal; Middle cerebral artery occlusion; Anesthetic method; Isoflurane; Rat
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-13443 (URN)10.1016/j.brainresprot.2005.01.002 (DOI)
    Available from: 2005-11-11 Created: 2005-11-11 Last updated: 2017-12-13Bibliographically approved
    4. Serum concentrations of 17β-estradiol in ovariectomized rats during 2 times 6 weeks crossover treatment by daily injections in comparison with slow-release pellets
    Open this publication in new window or tab >>Serum concentrations of 17β-estradiol in ovariectomized rats during 2 times 6 weeks crossover treatment by daily injections in comparison with slow-release pellets
    Show others...
    2005 (English)In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 1502-7686 (electronic) 0036-5513 (paper), Vol. 65, no 8, p. 699-706Article in journal (Refereed) Published
    Abstract [en]

    Estrogens exert widespread biological functions that reach far beyond their well-known role in reproduction. Exogenous administration of 17β-estradiol to ovariectomized experimental animals is of the utmost importance in elucidating its mechanisms of action. In the present study, we compared two different modes of exogenous administration of 17β-estradiol to ovariectomized rats in relation to the serum 17β-estradiol concentrations over prolonged periods of time. 17β-estradiol was administered either by slow-release pellets (Innovative Research of America, Sarasota, Fl. 34236, USA, 90-day release, NHH-115, 1.5 mg) or by daily subcutaneous injections of 15 µg 17β-estradiol dissolved in sesame oil. After 6 weeks, the mode of administration of estradiol was changed to the opposite method and continued for a further 6 weeks. Blood samples for measurement of serum 17β-estradiol were taken every second week. After 2 weeks, the serum concentrations of 17β-estradiol in group A initially receiving the pellets were 73 % higher (p<0.001) compared to those of group B receiving daily injections. The difference was even more prominent, 580 % (p<0.001), after 4 weeks. Steady state was reached at week 6 in group A, but already by week 4 in group B. Once steady state was reached, the concentrations were the same in both groups for the remainder of the experiment (12 weeks in total). Our study indicates that steady-state concentrations of 17β-estradiol occur 5-6 weeks later than the 48 h the manufacturer of the slow-release pellets claims.

    Keywords
    Estrogen; 17β-estradiol; rat; slow-release pellet
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-13444 (URN)10.1080/00365510500375206 (DOI)
    Available from: 2005-11-11 Created: 2005-11-11 Last updated: 2018-01-26
    5. Estradiol increases brain lesions in the cortex and lateral striatum after transient occlusion of the middle cerebral artery in rats: No effect of ischemia on galanin in the stroke area but decreased levels in the hippocampus
    Open this publication in new window or tab >>Estradiol increases brain lesions in the cortex and lateral striatum after transient occlusion of the middle cerebral artery in rats: No effect of ischemia on galanin in the stroke area but decreased levels in the hippocampus
    2005 (English)In: Peptides, ISSN 0196-9781, Vol. 26, no 11, p. 2257-2264Article in journal (Refereed) Published
    Abstract [en]

    A distinctive feature of galanin expression is that it is extensively increased by neuronal injury, estrogens, Alzheimer's disease and during development. Since stroke is amongst the clinically most important causes of neuronal injury we studied the tissue concentrations of galanin in a rat stroke model and the possibility of modulating this effect with estrogen. Transient focal middle cerebral artery ischemia was induced in rats that 2 weeks earlier underwent ovariectomy and received 1.5 mg 17β-estradiol slow-release or placebo pellets. The concentrations of galanin and neuropeptide Y were measured after observation periods of 3, 7 and 14 days in extracts of punch biopsies from both the lesioned and the contra lateral control hemisphere. The galanin levels were not changed in any of the brain regions studied except in the hippocampus where they were lower in the ischemic hemisphere in both the estrogen- and placebo-treated animals compared to the corresponding contra lateral intact hemisphere (p = 0.015). Estrogen treatment up-regulated galanin concentrations in both the ventral and dorsal hippocampus (p = 0.003). The effects on the galanin concentrations were similar after all observation periods: 3, 7 and 14 days (p = 0.144). No significant changes were observed in the concentration of neuropeptide Y in response to the lesions. The ischemic lesions were markedly larger in the estrogen-treated animals observed after 3 days compared to the corresponding control group. In the estrogen group the lesion was largest at bregma and the slice 2 mm anterior to the bregma, 82% and 435% larger than in the control group (p < 0.001). A similar, but much less pronounced (not statistically significant) difference was seen in the groups observed after 7 and 14 days. Earlier studies of lesions in the peripheral and central nervous systems have generally shown an up-regulation of galanin markers in response to but at a distance from the injury. Our results indicate that galanin is not involved in the response of the ischemic penumbra itself to stroke, whereas it may participate in the reactions of the neural stem-cell rich hippocampus to stroke.

    Keywords
    Galanin; Neuropeptide Y; Neuropeptides; Stroke; Cerebral ischemia; Estrogen; Neuroprotection; Middle cerebral artery occlusion; Rat
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-13445 (URN)10.1016/j.peptides.2005.04.013 (DOI)
    Available from: 2005-11-11 Created: 2005-11-11 Last updated: 2009-06-05
    6. Galanin administered intracerebroventricularly increases ischemic lesions measured 7 days after focal and transient occlusion of the middle cerebral artery in female rats
    Open this publication in new window or tab >>Galanin administered intracerebroventricularly increases ischemic lesions measured 7 days after focal and transient occlusion of the middle cerebral artery in female rats
    2005 (English)Article in journal (Refereed) Submitted
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-13446 (URN)
    Available from: 2005-11-11 Created: 2005-11-11
  • 46.
    Theodorsson, Annette
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Gunnarsson, Thorsteinn
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Karlsson, Per
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Hillman, Jan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Neurosurgery. Östergötlands Läns Landsting, Reconstruction Centre, Department of Neurosurgery UHL.
    Mobile CT Scanner in the Neurosurgery Intensive Care Unit (NICU): Improving the Bedside Scanning Procedure2001In: Proceedings 12th World Congress of Neurosurgery :: Sydney, Australia September 16 - 20, 2001 World Federation of Neurosurgical SocietiesBook of Proceedings 12th World Congress of Neurosurgery / [ed] Peter Reilly; Glenn McCulloch, Linköping: Linköpings universitet , 2001, p. 400-403Chapter in book (Other academic)
  • 47.
    Theodorsson, Annette
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Hilke, Susanne
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Rugarn, Olof
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Linghammar, Dan
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Serum concentrations of 17β-estradiol in ovariectomized rats during 2 times 6 weeks crossover treatment by daily injections in comparison with slow-release pellets2005In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 1502-7686 (electronic) 0036-5513 (paper), Vol. 65, no 8, p. 699-706Article in journal (Refereed)
    Abstract [en]

    Estrogens exert widespread biological functions that reach far beyond their well-known role in reproduction. Exogenous administration of 17β-estradiol to ovariectomized experimental animals is of the utmost importance in elucidating its mechanisms of action. In the present study, we compared two different modes of exogenous administration of 17β-estradiol to ovariectomized rats in relation to the serum 17β-estradiol concentrations over prolonged periods of time. 17β-estradiol was administered either by slow-release pellets (Innovative Research of America, Sarasota, Fl. 34236, USA, 90-day release, NHH-115, 1.5 mg) or by daily subcutaneous injections of 15 µg 17β-estradiol dissolved in sesame oil. After 6 weeks, the mode of administration of estradiol was changed to the opposite method and continued for a further 6 weeks. Blood samples for measurement of serum 17β-estradiol were taken every second week. After 2 weeks, the serum concentrations of 17β-estradiol in group A initially receiving the pellets were 73 % higher (p<0.001) compared to those of group B receiving daily injections. The difference was even more prominent, 580 % (p<0.001), after 4 weeks. Steady state was reached at week 6 in group A, but already by week 4 in group B. Once steady state was reached, the concentrations were the same in both groups for the remainder of the experiment (12 weeks in total). Our study indicates that steady-state concentrations of 17β-estradiol occur 5-6 weeks later than the 48 h the manufacturer of the slow-release pellets claims.

  • 48.
    Theodorsson, Annette
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Holm, L.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Galanin administered intracerebroventricularly increases ischemic lesions measured 7 days after focal and transient occlusion of the middle cerebral artery in female rats2005Article in journal (Refereed)
  • 49.
    Theodorsson, Annette
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Sinnescentrum, Department of Neurosurgery UHL.
    Holm, Lovisa
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Theodorsson, Elvar
    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.
    Hypothermia-induced increase in galanin concentrations and ischemic neuroprotection in the rat brain2008In: Neuropeptides, ISSN 0143-4179, E-ISSN 1532-2785, Vol. 42, no 1, p. 79-87Article in journal (Refereed)
    Abstract [en]

    The effects of hypothermia on galanin concentrations and the relation between ischemic brain lesions, hypothermia and galanin concentrations in a transient and focal rat stroke model were investigated in order to elucidate whether hypothermia-induced alterations in galanin concentrations could constitute a part of the established neuroprotective effect of hypothermia. Female rats were allocated to normothermia (37 °C) or hypothermia (33 °C) treatments during a 60 min microclip middle cerebral artery occlusion. The ischemic lesions were visualized after observation periods of 2 or 7 days and the concentration of galanin measured by radioimmunoassay in extracts of punch biopsies from both the lesioned and the contralateral control hemisphere. Hypothermia-induced an overall increase in the concentrations of immunoreactive galanin (p < 0.001). The elevated galanin levels were predominantly found in the non-ischemic control hemisphere, in the hippocampus, thalamus and the posterior part of parietal cortex. The galanin concentrations were lower in the ischemic hemisphere in both the normo- and hypothermic animals compared to the corresponding contra lateral intact hemisphere (p = 0.049). The factor of time, 2 respectively 7 days, did not show any significant difference regarding the galanin concentrations (p = 0.844). Multivariate analyses of variance revealed significant effect of ischemia on the size of the ischemic brain lesions (p = 0.001) but no overall effect of temperature when data from both 2 and 7 days observation periods were analyzed together. The ischemic lesions were generally larger at 33 degrees after 2 days (p = 0.230). Prolonged observation time of 7 days resulted in a significant reduction of the ischemic brain lesion (p = 0.011) with smaller ischemic lesions in the hypothermic group. Our data support the notion that hypothermia-induced increase in the tissue concentrations of galanin in the brain are the result of changes from optimal homeostatic conditions - the hypothermia-induced stress - rather than the ischemia/re-perfusion lesion induced changes in galanin concentrations. Hypothermia-induced elevation in galanin concentration is therefore not likely to be amongst the major protective mechanisms of hypothermia. © 2007 Elsevier Ltd. All rights reserved.

  • 50.
    Theodorsson, Annette
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Holm, Lovisa
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Modern anesthesia and peroperative monitoring methods reduce per- and postoperative mortality during transient occlusion of the middle cerebral artery in rats2005In: Brain Research Protocols, ISSN 1385-299X, E-ISSN 1872-809X, Vol. 14, no 3, p. 181-190Article in journal (Refereed)
    Abstract [en]

    Mortality and morbidity during and after occlusion of the middle cerebral artery in rats are important confounding factors which may be minimized by improved anesthesia and peroperative monitoring techniques. We describe state of the art techniques for inducing anesthesia, endotracheal intubation, ventilation and monitoring peroperatively in this context.

    Introducing the subtemporal approach of Tamura et al. in our laboratory 5 years ago, we experienced 25% peroperative and 24 h postoperative rat mortality when performing temporary clipping of the middle cerebral artery. This prompted us to abandon intraperitoneal anesthesia by chloral hydrate and ventilation by tracheotomy in favor of endotracheal intubation and isoflurane anesthesia (1% isoflurane in 30%:70% O2/N2O). These anesthetic techniques in combination with improved surgical skills have reduced our initial 25% peroperative- and 24 h postoperative mortality to 2.7% (1.8% peroperatively and 0.9% 24 h postoperatively). Furthermore, the following 14 days postoperative mortality rate was 1.8%. A total number of 203 rats have been operated with this method in different studies where a focal reperfusion stroke model combined with extended periods of observations were the cornerstone.

12 1 - 50 of 52
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