A De Novo Dominant Negative Mutation in DNM1L Causes Sudden Onset Status Epilepticus with Subsequent Epileptic Encephalopathy.

Mitochondrial dynamics such as fission and fusion play a vital role in normal brain development and neuronal activity. DNM1L encodes a dynamin-related protein 1 (Drp1), which is a GTPase essential for proper mitochondrial fission. The clinical phenotype of DNM1L mutations depends on the degree of mitochondrial fission deficiency, ranging from severe encephalopathy and death shortly after birth to initially normal development and then sudden onset of refractory status epilepticus with very poor neurologic outcome. We describe a case of a previously healthy 3-year-old boy with a mild delay in speech development until the acute onset of a refractory status epilepticus with subsequent epileptic encephalopathy and very poor neurologic outcome. The de novo missense mutation in DNM1L (c.1207C > T, p.R403C), which we identified in this case, seems to determine a unique clinical course, strikingly similar to four previously described patients in literature with the identical de novo heterozygous missense mutation in DNM1L.

Correction to: Advanced Robotic Therapy Integrated Centers (ARTIC): an international collaboration facilitating the application of rehabilitation technologies.

The original article [1] contains a small mistake concerning the ARTIC Team members mentioned in the Acknowledgements. The team member, Rocco Salvatore Calabrò had their name presented incorrectly. This has now been corrected in the original article.

Intrathecal Baclofen therapy in Germany: Proceedings of the IAB-Interdisciplinary Working Group for Movement Disorders Consensus Meeting.

Continuous intrathecal Baclofen application (ITB) through an intracorporeal pump system is widely used in adults and children with spasticity of spinal and supraspinal origin. Currently, about 1200 new ITB pump systems are implanted in Germany each year. ITB is based on an interdisciplinary approach with neurologists, rehabilitation specialists, paediatricians and neurosurgeons. We are presenting the proceedings of a consensus meeting organised by IAB-Interdisciplinary Working Group for Movement Disorders. The ITB pump system consists of the implantable pump with its drug reservoir, the refill port, an additional side port and a flexible catheter. Non-programmable pumps drive the Baclofen flow by the reservoir pressure. Programmable pumps additionally contain a radiofrequency control unit, an electrical pump and a battery. They have major advantages during the dose-finding phase. ITB doses vary widely between 10 and 2000 µg/day. For spinal spasticity, they are typically in the order of 100-300 µg/day. Hereditary spastic paraplegia seems to require particularly low doses, while dystonia and brain injury require particularly high ones. Best effects are documented for tonic paraspasticity of spinal origin and the least effects for phasic muscle hyperactivity disorders of supraspinal origin. Oral antispastics are mainly effective in mild spasticity. Botulinum toxin is most effective in focal spasticity. Myotomies and denervation operations are restricted to selected cases of focal spasticity. Due to its wide-spread distribution within the cerebrospinal fluid, ITB can tackle wide-spread and severe spasticity.

Ten-year follow-up in a case series of integrative botulinum toxin intervention in adolescents with chronic daily headache and associated muscle pain.

INTRODUCTION: A total of 83% of children report headache during a 6-month period. The estimated 1-year prevalence of chronic daily headache (CDH) in children is at least 1 to 2%. Muscle pain is associated with headache severity and chronicity. Muscle pain can be associated with active muscular trigger points, a functional concept still remaining a controversy. An integrated approach including bio-behavioral management is accepted as standard treatment but does not provide sufficient pain relief in all patients. OBJECTIVE: We report the individual clinical course of five adolescents with treatment-refractory CDH associated with focal muscle pain. We describe a concept of short-term integrative intervention including botulinum toxin (StiBo) in a personalized "follow the referred pain pattern" injection regimen with the focus on long-term follow-up. RESULTS: StiBo showed short-term efficacy on headache frequency and severity. In the long-term follow-up, CDH was not existent in any of the patients. CONCLUSION: The treatment may have enabled the patients to draw attention away from a repeated circle of muscle-triggered pain and withdrawal of daily activities toward self-driven activities, thereby potentially preventing the development of further chronification. To prove this hypothesis, a prospective, placebo-controlled study in young adolescents with CDH should be initiated including objective outcome parameters on muscular level.

Hip lateralisation in children with bilateral spastic cerebral palsy treated with botulinum toxin type A: a 2-year follow-up.

We investigated the effect of BoNT/A injection on hip lateralisation in children with bilateral spastic cerebral palsy and bilateral adductor spasticity. Pelvic radiographs using Reimers' migration index (MI) were evaluated from 27 children (n=9 females, n=18 males; mean age 5.2 ± 1.96 years; range: 2-10 years; initial MI <50%) with bilateral spastic cerebral palsy over a time period of 2 years. All received injections of BoNT/A (Dysport) every 12 weeks with a dose of 30 Units per kilogram body weight into adductor and medial hamstring muscles on both sides. The MI was calculated before treatment and after 1 and 2 years. The mean MI increased from 25.5% (range: 0-48) to 26.7% (+1.2%, range: 0-79) on the right side and from 28.0% (range: 0-40) to 30.6% (+2.6%, range: 3-84) on the left side over 2 years, respectively. Hips of one patient dislocated bilaterally. The mean MI remained stable over 2 years. Although a specific BoNT/A effect cannot be proven because of the open design of this study, we provide strong evidence that the MI can be kept stable for a time period of 2 years under non-surgical management including therapy with BoNT/A even in CP patients with a high risk for hip dislocation.

Botulinum toxin assessment, intervention and follow-up for paediatric upper limb hypertonicity: international consensus statement.

The primary objective of this paper was to evaluate the published evidence of efficacy and safety of botulinum neurotoxin (BoNT) injections in paediatric upper limb hypertonia (PULH). Secondary objectives included the provision of clinical context, based on evidence and expert opinion, in the areas of assessment, child and muscle selection, dosing, and adjunctive treatment. A multidisciplinary panel of authors systematically reviewed, abstracted, and classified relevant literature. Recommendations were based on the American Academy of Neurology (AAN) evidence classification. Following a literature search, 186 potential articles were screened for inclusion, and 15 of these met the criteria and were reviewed. Grade A evidence was found to support the use of BoNT to reach individualized therapeutic goals for PULH. There is grade B evidence (probably effective) for tone reduction following BoNT injections and grade U evidence (inconclusive) for improvement in upper limb (UL) activity and function. BoNT injections were generally found to be safe and well tolerated with the most common side effect identified as a transient decrease in grip strength.

Do patients with congenital hemiparesis and ipsilateral corticospinal projections respond differently to constraint-induced movement therapy?

This study investigates whether the type of corticospinal reorganization (identified by transcranial magnetic stimulation) influences the efficacy of constraint-induced movement therapy (CIMT). Nine patients (five males, four females; mean age 16y [SD 6y 5mo], range 11-30y) controlling their paretic hand via ipsilateral corticospinal projections from the contralesional hemisphere and seven patients (three males, four females; mean age 17y [SD 7y], range 10-30y) with preserved crossed corticospinal projections from the affected hemisphere to the paretic hand underwent 12 consecutive days of CIMT. A Wolf motor function test applied before and after CIMT revealed a significant improvement in the quality of upper extremity movements in both groups. Only in patients with preserved crossed projections, however, was this amelioration accompanied by a significant gain in speed, whereas patients with ipsilateral projections tended to show speed reduction. These data, although preliminary, suggest that patients with congenital hemiparesis and ipsilateral corticospinal projections respond differently to CIMT.

Botulinum toxin treatment of children with cerebral palsy - a short review of different injection techniques.

The intramuscular application of botulinum toxin type A (BoNT/A) has emerged to be an established treatment option to reduce muscular hyperactivity due to spasticity in children with cerebral palsy. Accurate injection is a prerequisite for efficient and safe treatment with BoNT/A. So far, treatment procedures have not been standardized. This paper is a short review of different injection techniques, i.e., manual needle placement as well as guidance by electromyography, electrical stimulation, and ultrasound. Advantages and disadvantages of the different injection techniques are discussed with a focus on needle positioning within the targeted muscle, injection close to the neuromuscular junction and diffusion of BoNT/A within the target muscles and through fascia. The additional information gained by each injection technique is weighed in terms of the clinical impact for children with cerebral palsy.

Effect of elevated glucose concentration on membrane voltage regulation in retinal capillary pericytes.

The influence of elevated glucose concentration on resting membrane voltage, electrogenic Na(+)-K(+)-ATPase, and ATP-sensitive potassium channels (KATP channels) was studied in cultured bovine retinal capillary pericytes using conventional microelectrodes. The resting membrane voltage in cells grown in medium containing 5 mM glucose (control) averaged -27 +/- 1.2 mV (mean +/- SE, n = 26) and was not different from cells grown in medium containing 22.5 mM glucose (-26 1.2 mV, n = 26). Addition of ouabain (10(-4) M), a specific inhibitor of the Na(+)-K(+)-ATPase, depolarized the membrane potential by 3.6 +/- 0.4 mV (n = 10) in cells grown under control conditions and 0.7 +/- 0.2 mV (n = 6) in cells grown under elevated glucose conditions. Thus, electrogenic activity of the Na(+)-K(+)-ATPase was significantly (P < 0.0001) reduced to 19% compared with control conditions. Electrogenic Na(+)-K(+)-ATPase activity could be partially restored (ouabain-induced depolarization delta V = 2.0 +/- 0.2 mV, n = 6) in cells grown with high glucose in the presence of the aldose reductase inhibitor tolrestat (10(-5) M). The potassium channel opener Hoe 234 (10(-6) M) induced membrane potential hyperpolarization in control cells (delta V = 7.3 +/- 1.2 mV, n = 13), which could be completely inhibited by the KATP channel blocker glibenclamide (10(-7) M, n = 5). This indicates that pericytes possess KATP channels. The effect of KATP channels on membrane voltage was not significantly changed (P = 0.16) in cells cultured under high-glucose conditions (delta V = 9.6 +/- 2.0 mV, n = 6).(ABSTRACT TRUNCATED AT 250 WORDS)

Insulin-induced hyperpolarization in retinal capillary pericytes.

PURPOSE: This study investigated the mechanism of insulin-induced membrane voltage hyperpolarization in retinal capillary pericytes, which possess electrical membrane properties typical for smooth muscle cells and are supposed to regulate retinal microcirculation by a contractile mechanism. METHODS: The mechanism of insulin-induced hyperpolarization was studied in cultured bovine retinal capillary pericytes using conventional microelectrodes. RESULTS: Resting voltage averaged -28 +/- 0.9 mV (mean +/- SEM, n = 45). Insulin (10(-9) to 10(-7) mol/l) induced a slow hyperpolarization in a dose-dependent fashion. Voltage change (delta V) was -3.1 +/- 0.4 mV (n = 14, P < 0.0001, = control) with an insulin concentration of 10(-8) mol/l. Blockade of potassium channels with Ba2+ (5 mmol/l) completely abolished the hyperpolarizing effect of insulin (n = 5). Apamin (10(-9) mol/l), a blocker of low-conductance Ca(2+)-activated potassium channels, also completely inhibited the insulin-induced hyperpolarization (n = 4). Blocking ATP-sensitive potassium channels with glibenclamide (10(-7) mol/l) did not reduce the hyperpolarizing action of insulin (delta V = -2.2 +/- 0.4 mV, n = 5, P = 0.29). Equivalent hyperpolarizations were recorded when insulin was added in the presence of ouabain (10(-4) mol/l) to inhibit the electrogenic Na+/-/K+/-ATPase (delta V = -3.5 +/- 1.0 mV, n = 4, P = 0.68). When pericytes were grown for 3 days in culture medium with elevated glucose concentrations (22.5 mmol/l), the resting membrane voltage and the insulin-induced hyperpolarization were not significantly altered. CONCLUSION: Insulin hyperpolarizes the membrane voltage of retinal pericytes probably mediated by activation of apamin-sensitive Ca(2+)-activated potassium channels. Therefore, hormonal modulation of membrane voltage by insulin might be an important factor in the regulation of pericyte contractility and retinal microcirculation under physiological conditions and in diabetes mellitus.

Membrane potentials in retinal capillary pericytes: excitability and effect of vasoactive substances.

Retinal capillary pericytes are believed to have a contractile function and to regulate retinal blood flow at the microvascular level. Membrane potential is an important control element for contractility in smooth muscle cells. In the present study, bovine retinal capillary pericytes have been grown in tissue culture and membrane potentials have been measured using glass microelectrodes. Resting potentials averaged -31 +/- 7 mV (n = 203). Relative K+ conductance was low, with a transference number for K+ of 0.16. Readdition of K+ to K(+)-depleted cells transiently hyperpolarized the membrane potential, probably by stimulating the electrogenic Na+/K+ transport. Repetitive spike-like depolarizations (action potentials) were induced by stimulating the Na+/K(+)-ATPase, by applying norepinephrine (10(-5) mol/l), and by adding 10 mmol/l Ba2+. These action potentials depended on the presence of extracellular Ca2+ and were inhibited by the Ca2+ antagonist nifedipine (10(-6) mol/l). Norepinephrine (10(-5) mol/l) depolarized the membrane by 7.4 +/- 3.5 mV (mean +/- SD, n = 49). This response was blocked by the alpha 1-antagonist prazosin (10(-5) mol/l). Histamine also led to a membrane depolarization of 8.6 +/- 2.8 mV (n = 49), which could be inhibited by the H1-antagonist diphenhydramine. Endothelin (10(-7) mol/l), vasopressin (10(-6) mol/l), and acetylcholine (10(-4) mol/l) had no major effects on membrane potential. The conclusion is that retinal capillary pericytes are excitable cells and react to several vasoactive substances.

Botulinum toxin treatment in cerebral palsy: evidence for a new treatment option.

Intramuscular injections of botulinum toxin type A (BTX-A) have increasingly been used to reduce spasticity in specific muscle groups in children with cerebral palsy. Targets of therapeutic efforts are improvement of gross motor function, alleviation of pain or facilitation of hygienic care. Placebo-controlled studies have shown the local and functional effectiveness of BTX-A for the treatment of dynamic pes equinus. Whether long-term treatment with BTX-A improves motor development and delays contractures is still under investigation.

Inhibitory conditioning stimulus in transcranial magnetic stimulation reduces the number of excited spinal motor neurons.

OBJECTIVE: To study the mechanisms of amplitude attenuation caused by a transcranial magnetic conditioning stimulus. Both conventional MEPs and the recently described triple stimulation technique (TST) were applied; the latter to improve the quantification of the response size decrease. METHODS: TST uses a peripheral collision method to eliminate the effects of desynchronization of the transcranial magnetic stimulation (TMS) induced spinal motor neuron discharges. The attenuation of motor evoked potentials (MEPs) and responses to TST was studied in 10 healthy volunteers using the conditioning-test paradigm with 2 ms interstimulus intervals. RESULTS: Conventional MEPs and responses to TST demonstrated a marked attenuation by the preceding conditioning stimulus in all subjects. The ratio of MEP to TST amplitudes was the same in conditioned and unconditioned responses. CONCLUSIONS: Our findings suggest that the transcranial conditioning stimulus does not change the degrees of desynchronization of spinal motor neuron discharges, but results in a reduced number of excited alpha motor neurons. This reduction can be estimated by both MEPs and TST.

How can hemodialysis-associated hypotension and dialysis-induced symptoms be explained and controlled--particularly in diabetic and arteriosclerotic patients?

Patients with diabetes and/or severe arteriosclerosis are often unable to tolerate volume removal during hemodialysis (HD) and develop hemodialysis-induced symptoms. These problems can be omitted by well-balanced correction of the acid/base status. We compared 20 high-risk patients which were either treated with standard HD (dialysate bicarbonate 33 mmol/l, treatment A) or treated with standard HD and additional administration of NaHCO3 (120-160 ml 8.4% NaHCO3 solution over the venous line during HD) to correct the metabolic acidosis to upper normal values (treatment B). The following parameters were compared: 1. Acid/base status; 2. EEG monitoring and clinical observation of dialysis-induced symptoms; 3. Invasive monitoring of circulation by Swan-Ganz thermodilution; 4. Ventilation, oxygen consumption and lactate production. Optimal correction of acid/base values resulted in symptom-free hemodialysis sessions with stable PaCO2 in the normal range, cardiovascular stability assessed by invasive monitoring, normal ventilation and higher oxygen consumption and decreased lactate production. Optimal correction of acid/base balance further led to the absence of EEG alterations and of dialysis-induced symptoms during treatment B as compared to treatment A. The baroreceptor response in these patients is usually disturbed due to sclerosis of the pressosensible vessels, especially the aortic arch and the pulmonary arteries impairing a compensatory increase of heart rate upon volume removal. However, chemoreceptors are able to increase sympathetic tone with preservation of blood pressure in this situation. In addition a decrease of PaO2 during volume removal can only be answered by an early increase of ventilation response due to stimulation of chemoreceptors provided that PaCO2 is maintained normal. Furthermore, normal cerebral blood flow also depends on a normal PaCO2. Based on these pathophysiological mechanisms the therapeutic strategy of additional bicarbonate administration to correct the acid/base status guarantees a stable normal PaCO2 and facilitates a symptom-free HD in high-risk patients.

Cardiac mortality prevention in uremic patients. Therapeutic strategies with particular attention to complete correction of renal anemia.

BACKGROUND: Left ventricular hypertrophy represents the major risk factor for cardiac mortality and morbidity, with cardiac mortality being the most important determinant for survival in dialysis patients. The prevalence of left ventricular hypertrophy is already high at initiation of dialysis and increases with time. Anemia is considered as the most important factor for the development of left ventricular hypertrophy. Others already demonstrated that with partial correction of renal anemia by erythropoietin a partial regression of the left ventricular mass can be achieved. PATIENTS AND METHODS: We investigated the effect of complete correction of renal anemia to normal hemoglobin values of 14 g/dl (Hct 42%) on left ventricular hypertrophy by echocardiography. Eight Patients entered the study 4-8 weeks after initiation of chronic hemodialysis with a mean hemoglobin of 9.5 +/- 1.3 g/dl). RESULTS: Left ventricular mass index (LVMI) decreased from 155 +/- 45 g/m2 to 123 +/- 18g/m2 (p < 0.05) within the observation period of 12 +/- 5 months. The results showed, that either normal left ventricular dimensions could be preserved or, if left ventricular hypertrophy was already present, complete regression was possible. CONCLUSION: Therefore, we propose that complete correction of renal anemia should be introduced into the therapy of dialysis patients along with strict adherence to established measures for the control of left ventricular hypertrophy: control of fluid overload and arterial hypertension and the use of ACE-inhibitors and betablockers. In addition, optimal correction of metabolic acidosis, control of the calcium-phosphate product and hyperparathyreoidism must be attempted. Thus, it should be possible to reverse left ventricular hypertrophy and its deleterious consequences in the dialysis population in order to improve survival and quality of life.

Regression of left ventricular hypertrophy in hemodialysis patients is possible.

Regression of left ventricular hypertrophy in hemodialysis patients is possible. Left ventricular hypertrophy represents the major risk factor for cardiac morbidity and mortality. Therefore, their regression is mandatory. Since the causes of uremia-associated left ventricular hypertrophy are multifactorial, various therapeutic options can be considered: optimal control of arterial hypertension and volume status, optimal correction of metabolic acidosis, best possible correction of hypoalbuminemia and severe secondary hyperparathyroidism, modern pharmacotherapeutic strategy for the treatment of heart failure (use of angiotensin-converting enzyme inhibitors in combination with angiotensin II receptor blockers and beta-blockers) and total correction of renal anemia. Following the proposed therapeutic strategies we could, by using echocardiography, distinguish in 100 hemodialysis patients the following 3 groups (on the average after 1.5 years): 36 patients with initially normal left ventricular mass index (LVMI (g/m2), F < 110; M < 130) maintained normal (group 1); in 31 patients with moderately increased LVMI full regression resulted (group 2); 33 patients with severely increased LVMI (group 3) had to be further divided into 2 sub-groups: 22 patients with significant improvement of LVMI, 11 patients with no, regression. For the first time we were able to show that it is possible to maintain initially normal LVMI during long-term treatment and to achieve complete regression and significant improvement of LVMI in our patients. However, since LVMI requires a long time to develop, a similarly long time must be estimated for its regression. However, 11 patients remained therapeutically resistant. In this group, severe heart diseases were often combined and highly prevalent, including ischemic heart and valve diseases and end-stage dilatative cardiomyopathy. These patients had to be transferred to cardiac surgery. Anemia is considered to be one of the most important factors for the development of left ventricular hypertrophy. Therefore, total correction of renal anemia has to be strongly recommended in addition to other measures of our therapeutic strategy to maintain full or significant regression of left ventricular hypertrophy.

Fast corticospinal system and motor performance in children: conduction proceeds skill.

Transcranial magnetic stimulation and motor performance tests were used to study the correlation between corticospinal maturation and actual motor performance in a group of young school children (n = 10, mean age = 7 years, age range = 6-9 years). The results were compared with normal adults (n = 10, mean age = 24 years, age range = 22-26 years). In children the central conduction time under the preinnervation condition of facilitation and the postexcitatory silent period was similar to that in adults. However, the central conduction time under relaxation, the latency jump (defined as the difference between the two preinnervation conditions), and the stimulus intensity were statistically different between children and adults (P < 0.01-0.001). Children did not reach the same level of performance as adults in any of the motor performance tasks (simple acoustic reaction time, tapping, ballistic movement, tracking, and diadochokinesis) (P < 0.05-0.01). The results indicate that at an early school age, children already possess mature fast corticospinal pathways able to access spinal motoneurons through the pyramidal tract. However, despite the partially adult-like level of neuronal maturation, young school children were not able to perform deliberate motor actions with the same proficiency as adults.

Endothelin-like immunoreactivity in the aqueous humour and in conditioned medium from cultured ciliary epithelial cells.

Endothelin-like immunoreactivity was detected in human (15.6 +/- 2.7 pg/ml) and bovine (11.1 +/- 0.98 pg/ml) aqueous humour of the eye. These concentrations are 2-3 times higher than the corresponding plasma levels. Cultured human nonpigmented ciliary epithelial cells released endothelin-like immunoreactivity with a maximum of 2.1 +/- 0.32 pg/(cm2* 48 h). The release was stimulated by fetal calf serum, thrombin, carbachol and phorbol ester and blocked by cycloheximide. Immunocytochemistry showed cytoplasmic staining of cultured human nonpigmented ciliary epithelial cells for endothelin-1. Endothelin-1 was shown to induce contractions in isolated human ciliary muscle by isometric force measurements. Endothelin in the aqueous humour may play a role in the regulation of intraocular pressure.

Prospective controlled cohort study to evaluate changes of function, activity and participation in patients with bilateral spastic cerebral palsy after Robot-enhanced repetitive treadmill therapy.

BACKGROUND: Robot-enhanced therapies are increasingly being used to improve gross motor performance in patients with cerebral palsy. AIM: To evaluate gross motor function, activity and participation in patients with bilateral spastic cerebral palsy (BS-CP) after Robot-enhanced repetitive treadmill therapy (ROBERT) in a prospective, controlled cohort study. METHODS: Participants trained for 30-60 min in each of 12 sessions within a three-week-period. Changes in Gross Motor Function Measure (GMFM 66) scores, standardized walking distance, self-selected and maximum walking speed (ICF domain "Activity"), and Canadian Occupational Performance Measure (COPM; "Participation") were measured. Outcome measures were assessed three weeks in advance (V1), the day before (V2) as well as the day after, and 8 weeks after ROBERT (V3 + V4). RESULTS: 18 patients with BS-CP participated; age 11.5 (mean, range: 5.0-21.8) years, body weight 36.4 (15.0-72.0) kg. GMFCS levels I-IV were: n = 4; 5; 8; 1. There was no significant difference comparing V1 and V2. GMFM 66 (total +2.5 points, Dimension D +3.8 and E +3.2) and COPM (Performance +2.1 points, Satisfaction +1.8 points) showed statistically significant improvements for V3 or V4 compared to V1 or V2 representing clinically meaningful effect sizes. Age, GMFCS level, and repeated ROBERT blocks correlated negatively with GMFM improvement, but not with COPM improvement. INTERPRETATION: Following ROBERT, this prospective controlled cohort study showed significant and clinically meaningful improvements of function in ICF domains of "activity" and "participation" in patients with BS-CP. Further assessment in a larger cohort is necessary to allow more specific definition of factors that influence responsiveness to ROBERT program.