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J K Gu

Publications and source records attributed to J K Gu.

6 recordsLinked to original sources
PubMed1996

[Study on major metabolites of 3H-1,2-dihydro-2-(4-methylphenylamino)-methyl-1-pyrrolizinone in rabbits].

The metabolites of a 750 mg oral dose of Z-47 [3H-1, 2-dihydro-2-(4-methylphenylamino) methyl-1-pyrrolizinone], a new anti-inflammatory and analgesic agent, in rabbit urine were separated and detected with high performance liquid chromatographic method. On basis of the chromatographic behavior of Z-47 metabolites and biotransformation pathways of drugs with partial structure of Z-47, the carboxylic derivative of Z-47 [4-(3H-1, 2-dihydro-1-pyrrolizinone-2-methylamino) benzoic acid] was proposed as a potential metabolite so that the compound was synthesized. The authentic substance was then compared with one of the metabolites by the chromatographic retention time and the ratio of their UV-absorbances at two wavelengths. The enzyme-hydrolyzed product of another metabolite was also analysed. It was consequently confirmed that the carboxylic derivative of Z-47 and its acyl beta-D-glucuronide are major metabolits of Z-47 in rabbits.

Animals↗
PubMed1993

Anti-arrhythmic effects of captopril on coronary occlusion and reperfusion periods in pigs.

Anti-arrhythmic effects of captopril (Cap) were studied in the anesthetized pigs using a reversible balloon catheter. Results showed that Cap did not exert any influence on the weight percentage of ischemic area to the whole left ventricle, on the levels of serum creatine kinase (CK) and creatine kinase isozyme (CK-MB), nor on the incidence and duration of transient and persistent tachycardia, but reduced the incidence of ventricular fibrillation (2/12, 1/12 in high-dose group pigs treated with Cap 6 mg.kg-1 in the first 10 min, 25 micrograms.kg-1.min-1 in the later 90 min and 12/21, 11/21 in control group treated with normal saline through the occlusion and reperfusion periods, respectively, P < 0.05). It was suggested that Cap did not exhibit direct (or non-specific, if any) effects on anti-arrhythmias.

Animals↗
PubMed1989

[The adverse effect of catheter ablation on the AV junction in experimental dogs].

The purpose of this study was to assess the adverse effects of catheter electrical ablation. Eighteen anesthetized mongrel dogs received 10-400 J of DC countershocks one to five times in each of them near the region of AVJ. Complete AV block was established, no pacemaker was implanted. Electrical unstability was seen nearly in all. Among the date of observation (1-547 days), 16 dogs died spontaneously and the other two were killed. Gross and microscopic examination revealed that cardiac damage produced by DC shock was diffusely spread over the endocardium/valve, myocardium and epicardial layers. The prominent lesions of the acute stage were myocytolysis and/or necrosis of myocardium/endocardium. In chronic stage, diffuse fibrosis and other types of tissue degeneration were revealed, some dogs had both acute and chronic lesions at the same time. Two dogs with perforated aortic valve revealed an elevation of PAEDP, one of them developed marked right heart failure and ascites. We proposed that the acute submicroscopic injury induced by DC shock may progress to a diffuse and irreversible pathologic changes. Therefore, the chronic adverse effects of catheter ablation should be evaluated carefully.

Animals↗
PubMedDate not supplied

Isolation and determination of bile acids.

In this article, the methods of isolation and determination of bile acids are reviewed. Methods for separation of bile acids from cattle and pig bile are given in detail. Isolation of a mixture of cholic acid and deoxycholic acids from cattle bile and their subsequent purification are described. The isolation and purification of hyodeoxycholic acid and other components of pig bile are also included. Methods for the determination of bile acids in various biological samples are reviewed, including enzyme assays, radioimmunoassay, enzyme immunoassay and chromatographic methods. Among chromatographic methods, separation and determination of bile acids by thin-layer chromatography, gas chromatography and high performance liquid chromatography are reviewed. Particular attention is given to the use of high performance liquid chromatography since this has recently been the most commonly applied method for the separation and determination of bile acids.

Animals↗