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Hui-zhen Wang

Publications and source records attributed to Hui-zhen Wang.

4 recordsLinked to original sources

Identification of a DNA methyltransferase gene carried on a pathogenicity island-like element (VPAI) in Vibrio parahaemolyticus and its prevalence among clinical and environmental isolates.

In this study we identified a putative virulence-associated DNA methyltransferase (MTase) gene carried on a novel 22.79-kb pathogenicity island-like element (VPAI) in V. parahaemolyticus. The V. parahaemolyticus MTase gene was shown by PCR to be prevalent (>98%) in pandemic thermostable direct hemolysin gene-positive isolates, which suggests that VPAI may confer unique virulence traits to pandemic strains of V. parahaemolyticus.

Amino Acid Sequence↗

M3-R/IK(M3)--a new target of antiarrhythmic agents.

AIM: To investigate the relationship between M3-R/IK(M3) and arrhythmia in order to find a new target for antiarrhythmic agents. METHODS: Using the acute ischemic model of rats and patch-clamp techniques, the effects of the M3 receptor on the occurrence of arrhythmias and its possible mechanisms were studied. RESULTS: In acute ischemic model of rats, the M3 receptor antagonist 4-diphenylacetoxy-N-methylpiperidine-methiodide (4DAMP) increased the occurrence of arrhythmias, and the M3 receptor agonist choline suppressed the onset and the development of arrhythmias (P < 0. 01). No change was observed after treatment with other receptor antagonists (M1, M2, and M4). With patch-clamp techniques, it was found that choline induced K+ current could be inhibited by 4DAMP. Antagonists toward M1, M2, and M4 receptors all failed to alter the current. CONCLUSION: Choline modulates the cellular electrical properties of the heart, probably by activating a K+ current via stimulation of the M3 receptor. M3-R/IK(M3) may act as a new target for antiarrhythmic agents.

Animals↗

Inactivation gating determines drug potency: a common mechanism for drug blockade of HERG channels.

AIM: To determine the mechanisms of interactions between different drugs and HERG channels. METHODS: Various antiarrhythmic (dofetilide, quinidine, azimilide, RP58866) and non-antiarrhythmic (terfenadine, nicotine) agents were used on HERG channels expressed in Xenopus oocyte. Whole-cell voltage-clamp techniques were used. RESULTS: All drugs produced concentration-dependent block of HERG current. The inhibition was markedly facilitated with voltage protocols favoring channel inactivation (eg, less negative holding potentials). Maneuvers that weakened channel inactivation (eg, elevation of external K+), relieved HERG blockade by all drugs. Moreover, the inhibitory potency was reduced by at least 20-300 fold with varying compounds when rapid C-type inactivation was removed by a mutation located between the transmembrane domains 5 and 6 (S631A). CONCLUSION: The inactivation gating of HERG channels determines the blocking potency of drugs. This mechanism might be common to drugs of various classes.

Animals↗