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Zirl, Austria

Stetkarova I.,Charles University | Kofler M.,Hochzirl Hospital
Clinical Neurophysiology | Year: 2013

Objective: The cutaneous silent period (SP) is a spinal inhibitory reflex, which suppresses activity in spinal motor nuclei. Transcranial magnetic stimulation (TMS) elicits a cortical SP, which represents GABAB receptor-mediated inhibition of cortical excitability. Baclofen as a strong GABAB agonist effectively reduces muscle hypertonia, however, it is not known whether intrathecal baclofen (ITB) may modulate spinal inhibitory circuits. Methods: We evaluated clinical and neurophysiological effects of ITB in ten patients with severe spasticity due to spinal cord injury (n=9) and chronic progressive multiple sclerosis (n=1). Neurophysiological assessment included H reflex and cutaneous and cortical SPs, before and 15, 30, 60, 90, 120, and 180. min after ITB bolus administration. Results: ITB suppressed soleus H reflex as early as 15. min after lumbar bolus injection; MAS scores declined after 1. h. Cortical SP end latency and duration increased progressively with a significant maximum 3. h following ITB bolus, whereas cutaneous SP latency and duration did not change significantly. Conclusion: The present findings suggest that baclofen does not affect the cutaneous SP, but prolongs the cortical SP. Significance: The spinal inhibitory circuitry of the cutaneous SP is not modulated by GABAB receptor-mediated activity, in contrast to the cortical inhibitory circuitry of the cortical SP, which is subject to powerful GABAB control. © 2012 International Federation of Clinical Neurophysiology. Source

Biedermann F.,Innsbruck Medical University | Fleischhacker W.W.,Innsbruck Medical University | Kemmler G.,Innsbruck Medical University | Ebenbichler C.F.,Innsbruck Medical University | And 2 more authors.
International Clinical Psychopharmacology | Year: 2014

Weight gain represents a frequent side effect of antipsychotic drug treatment. The current trial investigated the effect of add-on treatment with sibutramine in schizophrenia outpatients who had gained more than 7% of weight during the course of treatment. This 24-week placebo-controlled study evaluated the effects of sibutramine added to ongoing antipsychotic treatment. Weight, waist-hip ratio, BMI, blood pressure/pulse and ECG were monitored regularly. In addition, several laboratory tests were performed. Psychopathological symptoms and side effects were assessed frequently. Fifteen patients were assigned randomly to add-on treatment with sibutramine 10 mg or placebo. The two groups did not differ in weight, sociodemographic, or clinical data. Eleven patients were considered for statistical analysis. Significant weight loss was observed in the sibutramine group (mean=-6.1 kg), whereas patients on placebo experienced a mean weight gain of 1.9 kg. A reduction in HbA1c was apparent in the sibutramine but not in the placebo group. No significant between-group differences were found in changes in psychopathology or drug safety. This pilot trial suggests that adjunctive treatment with sibutramine may be safe and effective in schizophrenic patients with antipsychotic-induced weight gain. © 2014 Wolters Kluwer Health. Source

Kumru H.,Autonomous University of Barcelona | Kofler M.,Hochzirl Hospital
Clinical Neurophysiology | Year: 2012

Reorganization of neural circuits within the central nervous system following injury appears to be a means of compensatory mechanism for loss of function. Reorganization following spinal cord injury is known to evoke changes at the cortical and spinal cord levels. Recent studies, however, provide evidence of enhanced brainstem reflexes and alterations in excitatory and inhibitory interneuronal brainstem circuits, suggesting that reorganization following spinal cord injury occurs also at the brainstem level. Reversal of these changes by continuous intrathecal baclofen infusion to normal levels or beyond indicates strong GABAergic involvement. Rapid changes in the blink reflex and its prepulse inhibition following intrathecal baclofen bolus application that parallel clinical changes in muscle hypertonia suggest a muscle tone regulating effect of baclofen at the brainstem level. Enhanced brainstem reflexes in spinal cord injury patients may be the consequence of decreased GABA-mediated inhibition and/or strengthening of facilitatory connections due to either direct or indirect plastic changes occurring at the brainstem level. Modulation of brainstem reflexes by baclofen may foster the understanding of pathophysiological mechanisms underlying diseases with increased brainstem activity. Rehabilitation after central nervous system injury will always be a challenge, but understanding the mechanisms of reorganization of undamaged neural pathways may help to develop better strategies for enhancing neuronal plasticity and for implementing neuronal reorganization into carefully planned therapy. © 2011 International Federation of Clinical Neurophysiology. Source

Stetkarova I.,Na Homolce Hospital | Stetkarova I.,Center for Neuroscience and Neurological Recovery | Yablon S.A.,Center for Neuroscience and Neurological Recovery | Yablon S.A.,Baylor Institute for Rehabilitation | And 2 more authors.
Neurorehabilitation and Neural Repair | Year: 2010

Background. Intrathecal baclofen (ITB) effectively reduces muscle hypertonia; however, associated complications influence its utility and acceptance. Objective. To systematically review the literature on procedure- and device-related complications associated with ITB infusion therapy for adult muscle hypertonia of spinal or cerebral origin. Methods. The authors searched the PubMed database for full-length articles published in English that reported ITB-associated complications in adults. Of 147 articles retrieved, 32 full-length manuscripts and 10 case reports were reviewed in detail. Results. Overall, 558 complications were reported after 1362 pump implants (0.41 per implant). Methods for characterizing complications varied greatly between studies, as did complication rates, ranging from 0 to 2.24 per implant. Of the 558 complications, 148 (27%) were related to surgical procedures, 39 (7%) to pump problems, and 369 (66%) to catheter malfunctions. The overall complication rate was higher for studies that followed patients for more than 18 months on average (mean 0.56/implant) versus studies with shorter follow-up (0.23/implant, P <.05). Although correlation between the number of implants and the number of complications was significant (r =.58), the goodness of linear fit was poor because of clusters with varied complication rates. Conclusions. Catheter problems are relatively common and more frequent than pump or surgical procedure complications after ITB pump implantation. Higher complication rates should be expected in centers that follow patients for a longer period of time. Standardized data collection and complication-reporting procedures along with appropriate training should be implemented in centers offering ITB treatment for management of muscle hypertonia. © The Author(s) 2010. Source

Kofler M.,Hochzirl Hospital | Kumru H.,Autonomous University of Barcelona | Schaller J.,Hochzirl Hospital | Saltuari L.,Hochzirl Hospital | Saltuari L.,Research Unit for Neurorehabilitation
Clinical Neurophysiology | Year: 2013

Objective: Age and sex affect various reflexes in healthy humans. Their respective influence on prepulse inhibition (PPI) of the trigeminofacial blink reflex (BR) and BR excitability recovery has not as yet been investigated in detail. Methods: We studied the trigeminofacial BR bilaterally in 62 healthy volunteers (31 males, age 41.0 ± 13.2. years, mean ± SD, 31 females, 39.2 ± 11.7. years) following right supraorbital nerve stimulation. Single sweeps were recorded either alone (n= 8) or conditioned by a prepulse applied 100. ms earlier to the dominant index finger though ring electrodes (n= 8). Latency and amplitude of the ipsilateral R1 component, as well as latency and area-under-the-curve of the ipsilateral R2 and contralateral R2c components were measured in single traces and then averaged per subject. BR excitability recovery was established bilaterally following right supraorbital nerve stimulation with paired pulses. Six responses were averaged on-line per interstimulus interval (ISI 160, 300, and 500. ms). Results: Unconditioned BR did not differ significantly between males and females, but R2 and R2c latencies increased with age. Prepulse stimulation caused significant facilitation of R1 (latency and amplitude), and inhibition of R2 and R2c (latency and area), irrespective of age. PPI of R2 and R2c area was significantly more pronounced in men. BR excitability recovery was significantly influenced by age, but not by sex. Multiple regression showed inverse correlation of age with conditioned R2 and R2c area at ISI 300. ms and 500. ms (P< 0.01 each), indicating reduced excitability recovery. No parameter showed significant interaction of age. ×. sex. Conclusion: These data indicate less pronounced PPI of the trigeminofacial BR in females, concurring with previous reports of sex differences in protective reflexes, but also suggesting less rigorous filtering of information flow to the brain in females. Reduced BR excitability to paired-pulse stimulation may counteract age-related disinhibition of brainstem interneuronal circuitry. Significance: The present findings allow new insight into human brainstem physiology. © 2012 International Federation of Clinical Neurophysiology. Source

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