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Concept: Neurological disorders

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Hereditary sensory and autonomic neuropathies (HSANs) encompass a group of genetically inherited disorders characterized by sensory and autonomic dysfunctions. Familial dysautonomia (FD), also known as HSAN type III, is an autosomal recessive disorder that affects 1/3600 live births in the Ashkenazi Jewish population. The disease is caused by abnormal development and progressive degeneration of the sensory and autonomic nervous systems and is inevitably fatal, with only 50% of patients reaching the age of 40. FD is caused by a mutation in intron 20 of the Ikbkap gene that results in severe reduction in the expression of its encoded protein, inhibitor of kappaB kinase complex-associated protein (IKAP). Although the mutation that causes FD was identified in 2001, so far there is no appropriate animal model that recapitulates the disorder. Here, we report the generation and characterization of the first mouse models for FD that recapitulate the molecular and pathological features of the disease. Important for therapeutic interventions is also our finding that a slight increase in IKAP levels is enough to ameliorate the phenotype and increase the life span. Understanding the mechanisms underlying FD will provide insights for potential new therapeutic interventions not only for FD, but also for other peripheral neuropathies.

Concepts: Nervous system, DNA, Gene, Genetics, Gregor Mendel, Neurological disorders, Familial dysautonomia, Hereditary sensory and autonomic neuropathy

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Abstract There has been only one reported case of neuromuscular scoliosis following chronic inflammatory demyelinating polyneuropathy (CIDP). However, no cases of scoliosis that were treated with surgery secondary to CIDP have been previously described. A 16-year-old boy with CIDP was consultant due to the progression of scoliosis with the coronal curve of 86° from T8 to T12. Posterior correction and fusion with segmental pedicle screws were performed under intraoperative spinal cord monitoring with transcranial electric motor-evoked potentials. Although the latency period was prolonged and amplitude was low, the potential remained stable. Coronal curve was corrected from 86° to 34° without neurological complications. We here describe scoliosis associated with CIDP, which was successfully treated with surgery under intraoperative spinal cord monitoring.

Concepts: Medicine, Surgery, Report, Myelin, Case, Potential, Neurological disorders, Chronic inflammatory demyelinating polyneuropathy

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The prevalence of autism spectrum disorders (ASDs) has increased 20-fold over the past 50 years to >1% of US children. Although twin studies attest to a high degree of heritability, the genetic risk factors are still poorly understood. We analyzed data from two independent populations using u-statistics for genetically structured wide-locus data and added data from unrelated controls to explore epistasis. To account for systematic, but disease-unrelated differences in (non-randomized) genome-wide association studies (GWAS), a correlation between P-values and minor allele frequency with low granularity data and for conducting multiple tests in overlapping genetic regions, we present a novel study-specific criterion for ‘genome-wide significance’. From recent results in a comorbid disease, childhood absence epilepsy, we had hypothesized that axonal guidance and calcium signaling are involved in autism as well. Enrichment of the results in both studies with related genes confirms this hypothesis. Additional ASD-specific variations identified in this study suggest protracted growth factor signaling as causing more severe forms of ASD. Another cluster of related genes suggests chloride and potassium ion channels as additional ASD-specific drug targets. The involvement of growth factors suggests the time of accelerated neuronal growth and pruning at 9-24 months of age as the period during which treatment with ion channel modulators would be most effective in preventing progression to more severe forms of autism. By extension, the same computational biostatistics approach could yield profound insights into the etiology of many common diseases from the genetic data collected over the last decade.

Concepts: Gene, Genetics, Signal transduction, Action potential, Epilepsy, Absence seizure, Potassium channel, Neurological disorders

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Transthyretin-related familial amyloid polyneuropathy (TTR-FAP) typically arises as an autonomic neuropathy primarily affecting small fibres and it occurs in adult patients in their second or third decades of life. It progresses rapidly and can lead to death in approximately 10 years. Other phenotypes have been described in non-endemic areas.

Concepts: Evolution, Life, Amyloid, Amyloidosis, Area, Neurological disorders, Familial amyloid polyneuropathy, Transthyretin

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Dystonic storm is a frightening hyperkinetic movement disorder emergency. Marked, rapid exacerbation of dystonia requires prompt intervention and admission to the intensive care unit. Clinical features of dystonic storm include fever, tachycardia, tachypnea, hypertension, sweating and autonomic instability, often progressing to bulbar dysfunction with dysarthria, dysphagia and respiratory failure. It is critical to recognize early and differentiate dystonic storm from other hyperkinetic movement disorder emergencies. Dystonic storm usually occurs in patients with known dystonia, such as DYT1 dystonia, Wilson’s disease and dystonic cerebral palsy. Triggers such as infection or medication adjustment are present in about one-third of all events. Due to the significant morbidity and mortality of this disorder, we propose a management algorithm that divides decision making into two periods: the first 24 h, and the next 2-4 weeks. During the first 24 h, supportive therapy should be initiated, and appropriate patients should be identified early as candidates for pallidal deep brain stimulation or intrathecal baclofen. Management in the next 2-4 weeks aims at symptomatic dystonia control and supportive therapies.

Concepts: Intensive care medicine, Neurology, Parkinson's disease, Deep brain stimulation, Basal ganglia, Dystonia, Wilson's disease, Neurological disorders

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The recent spread of Zika virus (ZIKV) and its association with increased rates of Guillain Barre and other neurological disorders as well as congenital defects that include microcephaly has created an urgent need to develop animal models to examine the pathogenesis of the disease and explore the efficacy of potential therapeutics and vaccines. Recently developed infection models for ZIKV utilize mice defective in interferon responses. In this study we establish and characterize a new model of peripheral ZIKV infection using immunocompetent neonatal C57BL/6 mice and compare its clinical progression, virus distribution, immune response, and neuropathology with that of C57BL/6-IFNAR KO mice. We show that while ZIKV infected IFNAR KO mice develop bilateral hind limb paralysis and die 5-6 days post-infection (dpi), immunocompetent B6 WT mice develop signs of neurological disease including unsteady gait, kinetic tremors, severe ataxia and seizures by 13 dpi that subside gradually over 2 weeks. Immunohistochemistry show viral antigen predominantly in cerebellum at the peak of the disease in both models. However, whereas IFNAR KO mice showed infiltration by neutrophils and macrophages and higher expression of IL-1, IL-6 and Cox2, B6 WT mice show a cellular infiltration in the CNS composed predominantly of T cells, particularly CD8+ T cells, and increased mRNA expression levels of IFNg, GzmB and Prf1 at peak of disease. Lastly, the CNS of B6 WT mice shows evidence of neurodegeneration predominantly in the cerebellum that are less prominent in mice lacking the IFN response possibly due to the difference in cellular infiltrates and rapid progression of the disease in that model. The development of the B6 WT model of ZIKV infection will provide insight into the immunopathology of the virus and facilitate assessments of possible therapeutics and vaccines.

Concepts: Immune system, Medicine, Bacteria, Infection, Natural killer cell, Interferon, Neurology, Neurological disorders

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BackgroundHeadache associated with sexual activity is a well-known primary headache disorder. In contrast, some case reports in the literature suggest that sexual activity during a migraine or cluster headache attack might relieve the pain in at least some patients. We performed an observational study among patients of a tertiary headache clinic.MethodsA questionnaire was sent to 800 unselected migraine patients and 200 unselected cluster headache patients. We asked for experience with sexual activity during a headache attack and its impact on headache intensity. The survey was strictly and completely anonymous.ResultsIn total, 38% of the migraine patients and 48% of the patients with cluster headache responded. In migraine, 34% of the patients had experience with sexual activity during an attack; out of these patients, 60% reported an improvement of their migraine attack (70% of them reported moderate to complete relief) and 33% reported worsening. In cluster headache, 31% of the patients had experience with sexual activity during an attack; out of these patients, 37% reported an improvement of their cluster headache attack (91% of them reported moderate to complete relief) and 50% reported worsening. Some patients, in particular male migraine patients, even used sexual activity as a therapeutic tool.ConclusionsThe majority of patients with migraine or cluster headache do not have sexual activity during headache attacks. Our data suggest, however, that sexual activity can lead to partial or complete relief of headache in some migraine and a few cluster headache patients.

Concepts: Scientific method, Paracetamol, Attack, Headache, Headaches, Cluster headache, Neurological disorders, Hemicrania continua

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BACKGROUND: Migraine is one of the most common health problems for children and adolescents. If not successfully treated, it can impact patients and families with significant disability due to loss of school, work, and social function. When headaches become frequent, it is essential to try to prevent the headaches. For children and adolescents, this is guided by extrapolation from adult studies, a limited number of small studies in children and adolescents and practitioner preference. The aim of the Childhood and Adolescent Migraine Prevention (CHAMP) study is to determine the most effective preventive agent to use in children and adolescents. METHODS: CHAMP is a double-blinded, placebo-controlled, multicenter, comparative effectiveness study of amitriptyline and topiramate for the prevention of episodic and chronic migraine, designed to mirror real-world practice, sponsored by the US National Institute of Neurological Disorders and Stroke/National Institutes of Health (U01NS076788). The study will recruit 675 subjects between the ages of 8 and 17 years old, inclusive, who have migraine with or without aura or chronic migraine as defined by the International Classification of Headache Disorders, 2nd Edition, with at least 4 headaches in the 28 days prior to randomization. The subjects will be randomized in a 2:2:1 (amitriptyline: topiramate: placebo) ratio. Doses are weight based and will be slowly titrated over an 8-week period to a target dose of 1 mg/kg of amitriptyline and 2 mg/kg of topiramate. The primary outcome will be a 50% reduction in headache frequency between the 28-day baseline and the final 28 days of treatment (weeks 20-24). CONCLUSIONS: The goal of the CHAMP study is to obtain level 1 evidence for the effectiveness of amitriptyline and topiramate in the prevention of migraine in children and adolescents. If this study proves to be positive, it will provide information to the practicing physician as how to best prevent migraine in children and adolescents and subsequently improve the disability and outcomes.

Concepts: Non-steroidal anti-inflammatory drug, Paracetamol, Epilepsy, Acupuncture, Headache, Headaches, International Classification of Headache Disorders, Neurological disorders

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Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is a distinct epileptic syndrome with a broad range of severity even amongst affected members of the same pedigree, and the level of pharmacoresistance may reach 30%, close to that seen in sporadic focal epilepsies.

Concepts: Epilepsy, Frontal lobe, Postictal state, Temporal lobe epilepsy, Neurological disorders, Hippocampal sclerosis, Autosomal dominant nocturnal frontal lobe epilepsy, Frontal lobe epilepsy

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