Semaphorin 6A Improves Functional Recovery in Conjunction with Motor Training after Cerebral Ischemia

Background: We have previously identified Semaphorin 6a (Sema6A) as an upregulated gene product in a gene expression screen in cortical ischemia [1]. Semaphorin 6a was regulated during the recovery phase following ischemia in the cortex. Semaphorin 6a is a member of the superfamily of semaphorins involved in axon guidance and other functions. We hypothesized that the upregulation indicates a crucial role of this molecule in post-stroke rewiring of the brain. Here we have tested this hypothesis by overexpressing semaphorin 6a in the cortex by microinjection of a modified AAV2-virus. A circumscribed cortical infarct was induced, and the recovery of rats monitored for up to 4 weeks using a well-established test battery (accelerated rotarod training paradigm, cylinder test, adhesive tape removal). We observed a significant improvement in post-ischemic recovery of animals injected with the semaphorin 6a virus versus animals treated with a control virus. We conclude that semaphorin 6a overexpressed in the cortex enhances recovery after cerebral ischemia

On the importance of long-term functional assessment after stroke to improve translation from bench to bedside

Despite extensive research efforts in the field of cerebral ischemia, numerous disappointments came from the translational step. Even if experimental studies showed a large number of promising drugs, most of them failed to be efficient in clinical trials. Based on these reports, factors that play a significant role in causing outcome differences between animal experiments and clinical trials have been identified; and latest works in the field have tried to discard them in order to improve the scope of the results. Nevertheless, efforts must be maintained, especially for long-term functional evaluations. As observed in clinical practice, animals display a large degree of spontaneous recovery after stroke. The neurological impairment, assessed by basic items, typically disappears during the firsts week following stroke in rodents. On the contrary, more demanding sensorimotor and cognitive tasks underline other deficits, which are usually long-lasting. Unfortunately, studies addressing such behavioral impairments are less abundant. Because the characterization of long-term functional recovery is critical for evaluating the efficacy of potential therapeutic agents in experimental strokes, behavioral tests that proved sensitive enough to detect long-term deficits are reported here. And since the ultimate goal of any stroke therapy is the restoration of normal function, an objective appraisal of the behavioral deficits should be done

Attenuation of N2 amplitude of laser-evoked potentials by theta burst stimulation of primary somatosensory cortex

Theta burst stimulation (TBS) is a special repetitive transcranial magnetic stimulation (rTMS) paradigm, where bursts of low-intensity stimuli are applied in the theta frequency. The aim of this study was to investigate the effect of neuronavigated TBS over primary somatosensory cortex (SI) on laser-evoked potentials (LEPs) and acute pain perception induced with Tm : YAG laser stimulation. The amplitude changes of the N1, N2, and P2 components of LEPs and related subjective pain rating scores of 12 healthy subjects were analyzed prior to and following continuous TBS (cTBS), intermittent TBS (iTBS), intermediate TBS (imTBS), and sham stimulation. Our results demonstrate that all active TBS paradigms significantly diminished the amplitude of the N2 component, when the hand contralateral to the site of TBS was laser-stimulated. Sham stimulation condition had no significant effect. The subjective pain perception also decreased during the experimental sessions, but did not differ significantly from the sham stimulation condition. The main finding of our study is that TBS over SI diminished the amplitude of the N2 component evoked from the contralateral side without any significant analgesic effects. Furthermore, imTBS produced responses similar to those observed by other forms of TBS induced excitability changes in the SI

Sodium-Dependent Vitamin C Transporter 2 (SVCT2) Expression and Activity in Brain Capillary Endothelial Cells after Transient Ischemia in Mice

Expression and transport activity of Sodium-dependent Vitamin C Transporter 2 (SVCT2) was shown in various tissues and organs. Vitamin C was shown to be cerebroprotective in several animal models of stroke. Data on expression, localization and transport activity of SVCT2 after cerebral ischemia, however, has been scarce so far. Thus, we studied the expression of SVCT2 after middle cerebral artery occlusion (MCAO) in mice by immunohistochemistry. We found an upregulation of SVCT2 after stroke. Co-stainings with Occludin, Von-Willebrand Factor and CD34 demonstrated localization of SVCT2 in brain capillary endothelial cells in the ischemic area after stroke. Time-course analyses of SVCT2 expression by immunohistochemistry and western blots showed upregulation in the subacute phase of 2–5 days. Radioactive uptake assays using 14C-labelled ascorbic acid showed a significant increase of ascorbic acid uptake into the brain after stroke. Taken together, these results provide evidence for the expression and transport activity of SVCT2 in brain capillary endothelial cells after transient ischemia in mice. These results may lead to the development of novel neuroprotective strategies in stroke therapy

Tumoröse Schwellung des Sehnerven – Malignom oder isolierte Neurosarkoidose?

Schilling M, Rogalewski A, Ringelstein EB, Nabavi DG. Tumoröse Schwellung des Sehnerven – Malignom oder isolierte Neurosarkoidose? In: 79. Kongress der Deutschen Gesellschaft für Neurologie (DGN) mit Fortbildungsakademie Mannheim, 20.–24. 9. 2006 . Aktuelle Neurologie. Vol 33. Georg Thieme ; 2006

Eine einfache Methode zur Markierung der Zielregion bei komplizierten Muskelbiopsien

Rogalewski A, Gregor N, Ringelstein EB, Schilling M. Eine einfache Methode zur Markierung der Zielregion bei komplizierten Muskelbiopsien. In: 79. Kongress der Deutschen Gesellschaft für Neurologie (DGN) mit Fortbildungsakademie Mannheim, 20.–24. 9. 2006 . Aktuelle Neurologie. Vol 33. Georg Thieme; 2006

Stroke Knowledge Among Stroke Support Group Members

Weltermann BM, Homann J, Rogalewski A, Brach S, Voss S, Ringelstein EB. Stroke Knowledge Among Stroke Support Group Members. Stroke. 2000;31(6):1230-1233.Background and Purpose—Community stroke education is needed to improve early stroke recognition and reduce delays in the referral of stroke patients. In some regions, stroke support groups are important promoters of regional stroke education. However, there are no data about the level of stroke knowledge among support group members that support this promotional role. Methods—We performed a cross-sectional questionnaire survey among 11 German stroke support groups. The questionnaire asked for stroke knowledge and sociodemographic and medical data. Stroke knowledge was excellent if a participant knew (1) at least 2 stroke symptoms (good symptom knowledge) and (2) at least 2 stroke risk factors (good risk factor knowledge), as well as knowing (3) that immediate hospital admission or an emergency call is necessary in case of stroke (good action knowledge). Results—A total of 133 members (96.2%) of 11 stroke support groups took part in the study. Mean age was 65.3 years (SD 11.2 years). Fifty-four percent of subjects were female, 72.8% were retired, and 69.8% were stroke patients. Of the participants, 80.3% had good symptom knowledge, 64.7% had good risk factor knowledge, and 79.7% had good action knowledge. Stroke knowledge was excellent in 44.0% of subjects. Logistic regression analysis showed that age Conclusions—Overall, members of stroke support groups are well informed about all aspects of modern stroke care. Because of their knowledge and personal experience, support groups should be viewed as important partners in community stroke education

Postvaccinöse, akut disseminierte Enzephalomyelitis mit Besserung nach Plasmapherese

Rogalewski A, Duning T, Ringelstein EB, Nabavi DG, Hasselblatt M, Schäbitz W-R. Postvaccinöse, akut disseminierte Enzephalomyelitis mit Besserung nach Plasmapherese

Stroke Knowledge Among Stroke Support Group Members

Weltermann BM, Homann J, Rogalewski A, Brach S, Voss S, Ringelstein EB. Stroke Knowledge Among Stroke Support Group Members. Stroke. 2000;31(6):1230-1233.Background and Purpose—Community stroke education is needed to improve early stroke recognition and reduce delays in the referral of stroke patients. In some regions, stroke support groups are important promoters of regional stroke education. However, there are no data about the level of stroke knowledge among support group members that support this promotional role. Methods—We performed a cross-sectional questionnaire survey among 11 German stroke support groups. The questionnaire asked for stroke knowledge and sociodemographic and medical data. Stroke knowledge was excellent if a participant knew (1) at least 2 stroke symptoms (good symptom knowledge) and (2) at least 2 stroke risk factors (good risk factor knowledge), as well as knowing (3) that immediate hospital admission or an emergency call is necessary in case of stroke (good action knowledge). Results—A total of 133 members (96.2%) of 11 stroke support groups took part in the study. Mean age was 65.3 years (SD 11.2 years). Fifty-four percent of subjects were female, 72.8% were retired, and 69.8% were stroke patients. Of the participants, 80.3% had good symptom knowledge, 64.7% had good risk factor knowledge, and 79.7% had good action knowledge. Stroke knowledge was excellent in 44.0% of subjects. Logistic regression analysis showed that age Conclusions—Overall, members of stroke support groups are well informed about all aspects of modern stroke care. Because of their knowledge and personal experience, support groups should be viewed as important partners in community stroke education