Biomedical subjects

Hui-Ming Chen

Publications and source records attributed to Hui-Ming Chen.

4 recordsLinked to original sources

PubMed2004

Role of histamine and acid back-diffusion in modulation of gastric microvascular permeability and haemorrhagic ulcers in betel-quid-fed rats.

Evidence concerning the pathogenesis of gastric haemorrhagic ulcer produced by betel quid chewing (BQC) is lacking. This research first proposes that alterations of mast cell histamine release and gastric acid back-diffusion are important in modulating gastric microvascular permeability and mucosal haemorrhagic ulcer in BQC-fed rats. The effects of several histamine receptor antagonists on this ulcer model also were evaluated. Male Wistar rats were fed with BQC diet or normal pellet diet. After 1, 30 and 90 day(s), rat stomachs were irrigated for 3 h with either normal saline or simulated gastric juice. Gastric acid back-diffusion, mucosal histamine concentration, microvascular permeability, as well as luminal haemoglobin content and ulcer areas were determined. Severe gastric haemorrhage and mucosal ulcerations, particularly in acidic stomachs, were observed in BQC-fed rats. A high correlation was observed between histamine and gastric haemorrhage, as well as between acid back-diffusion and mucosal ulceration was found in rats fed with BQC. This haemorrhagic ulcer in BQC-fed rats was effectively ameliorated by intragastric ketotifen, ranitidine or their combination. In conclusion, enhancement of acid back-diffusion, mast cell histamine release and microvascular permeability is important in modulating gastric haemorrhage and ulcer in BQC-fed rats.

Animals↗

PubMed2004

[The structure and function of tmRNA].

tmRNA is a dual small RNA similar to a tRNA and a mRNA which plays an important role in an unusual mode of translation--trans translation. Recently, it was found that tmRNA had something to do with regulating gene expression and cell cycle. So the researchers have paid much attention on such area. Furthermore, it is an important part in RNomics era. This article reviews the progress about the structure and function of tmRNA in recent years.

Base Sequence↗

PubMed2003

Synergic and competitive inhibition effect between two kinds of arylamines in the formation of hemoglobin adduct in vitro.

This article presents our work with HPLC-UV to determine hemoglobin adducts produced by adduction reaction among 4-aminobiphenyl (4-ABP) or/and 2-naphthylamine (2-NA) and human hemoglobin in vitro. The results showed that HPLC-UV could efficiently be used to detect aromatic amine-hemoglobin adduct. Two kinds of optimized linear models modified from the traditional dose-response model were screened out. The models implied that synergic effect exists between the two kinds of arylamines adducted with hemoglobin and competitive inhibition effect occurs in the formation of hemoglobin adduct when the two kinds of arylamines are present in the blood synchronously. The results indicate that models for dose-response relationship should take the effects of the other toxicants into consideration in the mixed pollutant system.

2-Naphthylamine↗

PubMed2002

Effects of lead on 4-aminobiphenyl pharmacokinetics in liver, kidney, spleen, testes, heart, lung and hemoglobin adduct for rat model.

Lead affects almost every system in the body and 4-aminobiphenyl increases the incidence of bladder cancer among human exposed to aromatic amines, but little attention has been paid to the effects of lead (heavy metals) on the distribution and metabolic kinetics of 4-ABP (organic pollutants) in the organisms of the terrestrial ecosystems. In this study, male S.D. rats as model animals drinking tap water with and without lead with i.p. injection of 4-aminophenyl were used to study 4-aminobiphenyl pharmacokinetics with statistical analysis in three types of information systems: (1) hemoglobin adduct in the blood; (2) distribution concentrations in liver, kidney, spleen, testes, heart and lung; (3) relative weights of the six organs. Kinetic equations of 4-aminobiphenyl-hemoglobin adduct for two groups of rats drinking water with and without lead were all linear. Principal components were obtained based on three types of variants: (1) variants of distribution concentrations; (2) variants of relative weights; (3) variants of hemoglobin adduct, distribution concentrations and relative weights. Through a comparison of two groups of principal components, the result implied that lead changed 4-aminobiphenyl distribution kinetics in the six organs, had significant effects on the six organ relative weights, and had also significant effects on all thirteen variants as a whole. Correlation analysis of the principal components showed that lead could not significantly change the relation of hemoglobin adduct with time after dosing 4-aminobiphenyl. However, another result indicated that lead considerably improved the correlation between hemoglobin adduct and the thirteen variants as a whole. This implied that hemoglobin adduct could characterize all the thirteen variants as an index of 4-aminobiphenyl pharmacokinetics for the rats drinking water with lead, which conclusion was not suitable for the rats drinking water without lead. The research indicated that heavy metals existing in the organisms play an important role in the studies on pharmacotoxicology of organic pollutants. Frequently, various xenobiotics (heavy metals and organic pollutants) enter organisms simultaneously, therefore heavy metals should be considered comprehensively in the pharmacotoxicology of organic pollutants in animals in the terrestrial ecosystems theoretically and practically.

Aminobiphenyl Compounds↗