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Biomedical subjects

B Zhong

Publications and source records attributed to B Zhong.

23 records · Page 2Linked to original sources

Details of the arrangement of the outer capsid of rice dwarf phytoreovirus, as visualized by two-dimensional crystallography.

Two-dimensional crystals were obtained from purified P8, an outer capsid protein of rice dwarf phytoreovirus. A filtered image of the two-dimensional crystal, in combination with the results of biochemical analysis, revealed the unit formation of the capsid protein, a capsomere structure, which appeared to be an approximately equilateral triangle with sides of approximately 6 nm and which was composed of a trimer of P8 protein. Details of the arrangements of the outer capsid of the virus are described.

Capsid↗

Direct continuous fluorometric assay for monoamine oxidase B.

The first direct and continuous fluorometric assay for monoamine oxidase B (MAO B) has been developed. E-2,5-Dimethoxycinnamylamine hydrochloride was designed and synthesized and was found to be an excellent substrate for MAO B (Km = 218 microM, Kcat = 435 min-1). This compound has an intense purple fluorescence when irradiated at lambda ex = 343 nm (lambda em = 393 nm) in Tris buffer, pH 9.0, or sodium phosphate buffer, pH 7.2, but under the same conditions, the corresponding aldehyde, the product of the MAO-catalyzed oxidation of E-,5-dimethoxycinnamylamine hydrochloride, does not fluoresce. The activity of MAO B, therefore, can be determined efficiently and rapidly by continuously following the decrease in fluorescence at 393 nm at enzyme concentrations as low as 100 nM. The change in fluorescence is linear up to a substrate concentration of 500 microM.

Animals↗

[Effect of concentrated xuefu zhuyu pill on proliferation of vascular smooth muscle cells in experimental atheriosclerosis rabbits observed by serologic pharmacological test].

Two in vitro experiments were performed for comparative study to evaluate the effect of concentrated Xuefu Zhuyu pill (CXZP), a Chinese traditional herbal medicinal mixture, on the proliferation of vascular smooth muscle cells (SMCs) of experimental atherosclerosis rabbits by serologic pharmacological test. The first experiment approach adopted the addition of the rabbit's serum to the culture medium while in the second experiment the CXZP was added to the medium directly. Results showed that both the serum with CXZP and the CXZP extract itself could inhibit the proliferation of SMC significantly and dose-dependently, and the inhibitory action of the latter was more potent than the former one. It suggested that CXZP could inhibit the proliferation of SMC both in vivo and in vitro, the decrease of effectiveness in vivo might be due to the non-absorption of some active ingredient of CXZP or due to metabolic inactivation.

Animals↗

Diltiazem concentrations in plasma vs PR intervals on electrocardiogram in 8 men.

AIM: To develop an acute tolerant model in describing relationship between diltiazem (Dil) concentrations in plasma and PR intervals on ECG in men. METHOD: Both plasma concentrations of Dil and changes of ECG were simultaneously determined after po Dil 90 mg in 8 men. RESULTS: A two-compartmental pharmacokinetic model with first-order input gave a good fitting for the plasma concentration of Dil. Corresponding pharmacokinetic parameters were estimated: t1/2 beta, 5.9 +/- 1.0 h; MRT, 15.9 +/- 1.0 h; t0, 0.38 +/- 0.07 h; tmax, 2.7 +/- 0.4 h, and Cmax, 161 +/- 60 micrograms.L-1. The good fittings for plasma concentration-effect data were obtained with tolerant model E = S x C/(1 + T/T50). The pharmacodynamic parameters were given as follows: S, 829 +/- 293 s.g-1.L; Kt0, 0.037 +/- 0.024 h-1 and T50, 10 +/- 4 micrograms.L-1. CONCLUSION: Relationship between Dil concentrations in plasma and PR interval changes in men after po 90 mg was described using an acute tolerant model.

Adult↗

[Mutagenicity study of eight diesel emission samples].

Mutagenicity of eight diesel emission samples were examined by the Microsuspension test. The results showed that four samples were positive, and the others were negative. We also compared the method with the standard Ames test. The data showed that the microsuspension test is sensitive and economical. The microsuspension test method is useful for determining mutagenicity of environmental mutagens.

Air Pollutants↗