Biomedical subjects

J Hui

Publications and source records attributed to J Hui.

58 records · Page 4Linked to original sources

PubMed1979

Myocardial positron tomography with manganese-52m.

The biodistribution of radiomanganese (54Mn) was studied in mice, rats, and dogs. Disappearance of radioactivity from the blood was extremely rapid, with a half-time of approximately 0.8 minutes. This resulted in very favorable myocardium-to-blood ratios, even at early times after administration. The myocardial uptake in dogs was greater than 3% at three and 15 minutes, with myocardium-to-blood ratios of about 40:1 at 15 minutes. Positron tomograms obtained with 52mMn clearly demonstrated regional myocardial perfusion. There was good correlation (r = 0.89) of microsphere-to-radiomanganese distribution in the infarcted dog heart.

Animals↗

PubMed1978

The pleiotropic effect of spontaneous single-step variant production in Mycobacterium intracellulare.

A strain of M. intracellulare, AT 13786, derived from human sputum, gave rise to transparent and opaque colony forms which were cloned and investigated. From the results the conclusion was drawn that the opaque form was a mutant of the transparent type and possessed alterations in the cell envelope which were responsible for enhanced permeability. The opaque form was more susceptible to a number of antibiotics; it grew faster in standard medium, and was not dependent on tween for dextrose utilization. Tween enhanced the antibiotic susceptibility of the opaque form more than that of the transparent. The avirulent opaque colony form of the pathogenic strain serotype Boone also revealed a loss of tween dependence for dextrose utilization. The significance of the overall change has been discussed with respect to the question of virulence.

Anti-Bacterial Agents↗

PubMed1977

Permeability barrier to rifampin in mycobacteria.

A strain of Mycobacterium intracellulare that exhibited natural resistance to rifampin was isolated. The ribonucleic acid polymerase was found to be susceptible to rifampin. Studies with Tween 80 suggested that a permeability barrier against rifampin was present in the intact organism. A type strain of Mycobacterium smegmatis, ATCC 607, considered resistant to rifampin also demonstrated a permeability barrier. The possibility that rifampin resistance in naturally occurring strains of mycobacteria and variable levels of resistance in strains of certain species of this organism are due to permeability barriers is discussed.

DNA-Directed RNA Polymerases↗

PubMedDate not supplied

Disposition of tablet and capsule formulations of digoxin in the elderly.

STUDY OBJECTIVE: To compare digoxin tablets and liquid-filled capsules with respect to excretion of the drug and its metabolites in urine and feces at steady state. DESIGN: A randomized, crossover trial, each period lasting 3 weeks, with no washout period. SETTING: A university hospital. PATIENTS: Six patients, five of whom were elderly, with histories of gastrointestinal disorders, such as hypochlorhydria, intestinal bacterial overgrowth, and inflammatory bowel disease. INTERVENTIONS: The patients received digoxin once/day in either tablet or capsule form for 3 weeks, and then were switched to the other formulation. Total urinary and fecal excretion from the last 3 days of each regimen were analyzed for the drug and metabolites. MEASUREMENTS AND MAIN RESULTS: No statistically significant differences were found between tablets and capsules in recovery of digoxin or its metabolites in urine or feces (p = 0.05). One subject had a 4-fold increase in urinary drug excretion and 50% decrease in fecal excretion after taking the capsules compared with tablets. Intersubject variability in extent and type of metabolite excretion was greater than intrasubject variability. CONCLUSIONS: Fecal analyses may be an accurate way to classify patients as formers of digoxin reduction products.

Aged↗