New hyperekplexia mutations provide insight into glycine receptor assembly, trafficking, and activation mechanisms

Background: Hyperekplexia mutations have provided much information about glycine receptor structure and function. Results: Weidentified and characterized nine new mutations. Dominant mutations resulted in spontaneous activation, whereas recessive mutations precluded surface expression. Conclusion: These data provide insight into glycine receptor activation mechanisms and surface expression determinants. Significance: The results enhance our understanding of hyperekplexia pathology and glycine receptor structure-function. © 2013 by The American Society for Biochemistry and Molecular Biology, Inc. Published in the U.S.A

Effects of Respiration on Left Ventricular Diastolic Function in Healthy Children

Pulsed Doppler echocardiographic indices of mitral valve filling were measured in 20 healthy children, between 3 and 125 years old, in order to evaluate the effects of spontaneous respiration on left ventricular diastolic filling patterns. There were significant respiratory variations in four parameters of left ventricular diastolic function: The peak early filling velocity, the ratio of early to late peak filling velocity, and the ratio of early to late diastolic velocity-time integral decreased significantly during inspiration (mean decrease 7%, P<0·05; 16%, P<0·01; and 12%, P<0·05, respectively). On the other hand there was a significant increase in late peak filling velocity with inspiration (10% increase, P<0·05). Other variables of left ventricular diastolic filling were unchanged with inspiration. These results suggest that assessment of left ventricular diastolic function in children should be standardized with regard to respiratory phases in any clinical application. (Eur Heart J 1996; 17: 453%456)Scopu

Monophasic demyelinating disease of the central nervous system associated with Hepatitis A infection

no abstract availabl

Novel mutations consolidate KCTD7 as a progressive myoclonus epilepsy gene

PubMed ID: 22693283Background The progressive myoclonus epilepsies (PMEs) comprise a group of clinically and genetically heterogeneous disorders characterised by myoclonus, epilepsy, and neurological deterioration. This study aimed to identify the underlying gene(s) in childhood onset PME patients with unknown molecular genetic background. Methods Homozygosity mapping was applied on genome-wide single nucleotide polymorphism data of 18 Turkish patients. The potassium channel tetramerisation domain-containing 7 (KCTD7) gene, previously associated with PME in a single inbred family, was screened for mutations. The spatiotemporal expression of KCTD7 was assessed in cellular cultures and mouse brain tissue. Results Overlapping homozygosity in 8/18 patients defined a 1.5 Mb segment on 7q11.21 as the major candidate locus. Screening of the positional candidate gene KCTD7 revealed homozygous missense mutations in two of the eight cases. Screening of KCTD7 in a further 132 PME patients revealed four additional mutations (two missense, one in-frame deletion, and one frameshift-causing) in five families. Eight patients presented with myoclonus and epilepsy and one with ataxia, the mean age of onset being 19 months. Within 2 years after onset, progressive loss of mental and motor skills ensued leading to severe dementia and motor handicap. KCTD7 showed cytosolic localisation and predominant neuronal expression, with widespread expression throughout the brain. None of three polypeptides carrying patient missense mutations affected the subcellular distribution of KCTD7. Discussion These data confirm the causality of KCTD7 defects in PME, and imply that KCTD7 mutation screening should be considered in PME patients with onset around 2 years of age followed by rapid mental and motor deterioration