TTX-sensitive Na+ and nifedipine-sensitive Ca2+ channels in rat vas deferens smooth muscle cells

The inward currents in single smooth muscle cells (SMC) isolated from epididymal part of rat vas deferens have been studied using whole-cell patch-clamp method. Depolarising steps from holding potential -90 mV evoked inward current with fast and slow components. the component with slow activation possessed voltage-dependent and pharmacological properties characteristic for Ca2+ current carried through L-type calcium channels (I-Ca). the fast component of inward current was activated at around -40 mV, reached its peak at 0 mV, and disappeared upon removal of Na ions from bath solution. This current was blocked in dose-dependent manner by tetrodotoxin (TTX) with an apparent dissociation constant of 6.7 nM. On the basis of voltage-dependent characteristics, TTX sensitivity of fast component of inward current and its disappearance in Na-free solution it is suggested that this current is TTX-sensitive depolarisation activated sodium current (I-Na) Cell dialysis with a pipette solution containing no macroergic compounds resulted in significant inhibition of I-Ca (depression of peak I-Ca by about 81% was observed by 13 min of dialysis), while I-Na remained unaffected during 50 min of dialysis. These data draw first evidence for the existence of TTX-sensitive Na+ current in single SMC isolated from rat vas deferens. These Na+ channels do not appear to be regulated by a phosphorylation process under resting conditions. (C) 1999 Elsevier Science B.V. All rights reserved.Natl Acad Sci Ukraine, Bogomoletz Inst Physiol, Nerve Muscle Physiol Dept, UA-24 Kiev, UkraineUniversidade Federal de São Paulo, Escola Paulista Med, Dept Pharmacol, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Pharmacol, São Paulo, BrazilWeb of Scienc

Sustainability, Peak oil

none4openDe leo Federica, Pier paolo Miglietta, Stefania Massari, Marcello RubertiDE LEO, Federica; Miglietta, PIER PAOLO; Massari, Stefania; Ruberti, Marcell

An international effort towards developing standards for best practices in analysis, interpretation and reporting of clinical genome sequencing results in the CLARITY Challenge

There is tremendous potential for genome sequencing to improve clinical diagnosis and care once it becomes routinely accessible, but this will require formalizing research methods into clinical best practices in the areas of sequence data generation, analysis, interpretation and reporting. The CLARITY Challenge was designed to spur convergence in methods for diagnosing genetic disease starting from clinical case history and genome sequencing data. DNA samples were obtained from three families with heritable genetic disorders and genomic sequence data were donated by sequencing platform vendors. The challenge was to analyze and interpret these data with the goals of identifying disease-causing variants and reporting the findings in a clinically useful format. Participating contestant groups were solicited broadly, and an independent panel of judges evaluated their performance. RESULTS: A total of 30 international groups were engaged. The entries reveal a general convergence of practices on most elements of the analysis and interpretation process. However, even given this commonality of approach, only two groups identified the consensus candidate variants in all disease cases, demonstrating a need for consistent fine-tuning of the generally accepted methods. There was greater diversity of the final clinical report content and in the patient consenting process, demonstrating that these areas require additional exploration and standardization. CONCLUSIONS: The CLARITY Challenge provides a comprehensive assessment of current practices for using genome sequencing to diagnose and report genetic diseases. There is remarkable convergence in bioinformatic techniques, but medical interpretation and reporting are areas that require further development by many groups