40 research outputs found
Hereditary spastic paraplegia type 31: A novel splice site donor mutation and intra-familial phenotypic variability
No full textHereditary spastic paraplegia type 31: a novel splice site donor mutation and intra-familial phenotypic variability
No full textSpastic paraplegia type 31: A novel REEP1 splice site donor variant and expansion of the phenotype variability
No full textMutations in REEP1 have been identified in three types of neurological disorders, autosomal dominant form of Hereditary Spastic Paraplegia type 31 (SPG31), autosomal dominant distal hereditary motor neuronopathy type VB (HMN5B), and autosomal recessive form of congenital axonal neuropathy and diaphragmatic palsy. Previous studies demonstrated different molecular pathogenesis in SPG31, including loss-of-function, gain-of-function and haploinsufficiency. A four-generation family from Japan, including 12 members, was investigated clinically and genetically. Seven affected members displayed pure spastic paraplegia. Impression of genetic anticipation was observed in the family, including tendency of earlier age-at-onset and increasing severity in subsequent generations. Genetic analysis revealed a heterozygous intronic variant, c.303+2T > A, in REEP1, which segregated with disease, and was also identified in one unaffected member. The variant causes exon 4 skipping leading to frame shift and a truncated transcript identified by complementary DNA sequencing of reverse transcription polymerase chain reaction products. Measurement of REEP1 transcripts in lymphocytes demonstrated a reduction through nonsense mediated mRNA decay (NMD). Our study demonstrated further evidence of allelic heterogeneity in SPG31, mutant REEP1 mRNA dosage effects through NMD and intra-familial phenotype variability
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Enabling Cathode With High Active Material Ratio Through Dry Process
No full textAs demand for electric vehicles and other electronic devices advances in the realm of possibilities, the demand for better-performing batteries with higher energy densities, fast charging capability, longer lifetime, etc… rises. One solution out of the many is to increase the cathode active material(CAM) percentage of the electrode, reducing the inactive material of the electrode. This solution theoretically results in lower parasitic side reactions and increased volumetric energy density. However, with the widely used solvent-based slurry casting processes, it is difficult to achieve high CAM electrodes as electrodes become more prone to cracking. In this study, by utilizing a dry electrode coating process, we fabricate a variety of high NCM percentage electrodes, up to 99.5%, and demonstrate stable full cell cycling of 95%-NCM and 97%-NCM cell with capacity retention of 86.3% and 83% after 100 cycles, respectively. However, 99%-NCM showed lower cycling performance, indicating the existence of an active material to inactive material ratio threshold in the cathode composition. The phenomenon is studied through SEM, 4-point probe test, and EIS data. These results open up possibilities for increasing the active material ratio in electrode fabrication to achieve higher energy density, thus reducing the thickness of the layer and the battery
Differential respiratory effects of HCO3- and CO2 applied on ventral medullary surface of rats
No full text To estimate whether H+ is the unique stimulus of the medullary chemosensor, ventilatory effects of HCO3- and/or CO2 applied on the ventral medullary surface using an improved superfusion technique and of CO2 inhalation were compared in halothane-anesthetized spontaneously breathing rats. Superfusion with low [HCO3-]-acid mock cerebrospinal fluid (CSF) (normal Pco2) induced a significant increase in ventilation, with an accompanying reduction in endtidal Pco2 (PETco2). High [HCO3-]-alkaline CSF depressed ventilation. Changes in Pco2 of superfusing CSF, on the other hand, had no significant effect despite the similar changes in pH. Simultaneous decrease in [HCO3-] and Pco2 of mock CSF with normal pH also maintained stimulated respiration. CO2 inhalation during superfusion with various [HCO3-] solutions caused further increase in ventilation as PETco2 increased. The results suggest that the surface area of the rat ventral medulla contains HCO3- (or H+)-sensitive respiratory neural substrates which are, however, little affected by CO2 in the subarachnoid fluid. A CO2 (or CO2-induced H+)-sensitive chemosensor responsible for the increase in ventilation during CO2 inhalation may exist elsewhere functionally apart from the HCO3- (or H+)-sensitive sensor in the examined surface area. </jats:p
