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Biomedical subjects

J Reinhardt

Publications and source records attributed to J Reinhardt.

At least 55 records · Page 3Linked to original sources
PubMed1990

Influenza.

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Aged↗
PubMed1989

Effect of enzyme inducers on the metabolism of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) in the rat.

The effect of enzyme inducers 3-methylcholanthrene (3-MC) and Aroclor 1254 (A-1254) on the metabolic fate of the dietary mutagen and carcinogen 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) in male F344 rats was studied in relation to single dose corn oil and untreated controls. The latter two groups were similar as regards metabolism of IQ. However, the ratio of total metabolites excreted in urine compared with those in feces was higher in A-1254 pretreated rats. In fact, this distinct excretory pattern stemmed from a lower level of IQ-N-sulfamate, and a considerably higher level of 5-OH-IQ sulfate ester, a major metabolite in urine of A-1254-injected rats. Interestingly, 5-OH-IQ glucuronide urinary levels were unaffected by the treatment. Thus, the direct 5-hydroxylation of IQ appears to be considerably increased by 3-MC and more so by A-1254, and under those conditions the resulting 5-OH-IQ is preferentially converted to the sulfate ester, in turn readily excreted in urine.

Animals↗
PubMed1987

Transfer of the tobacco-specific carcinogens N'-nitrosonornicotine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone and benzo[a]pyrene into the milk of lactating rats.

The extent to which some of the more prevalent and potent carcinogens in cigarette smoke could be transferred from circulating blood into the milk of lactating rats was determined. One hour after i.v. administration of benzo[a]pyrene (BaP), N'-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) to the dams, the levels of these carcinogens were determined in both blood and milk specimens. The average amount of radioactivity detected 1 h after administration of 14C-labeled BaP was 0.21% of the administered dose per ml of milk as compared with 0.17% per ml of blood. The amount of NNN in milk ranged from 0.20 to 0.36% of the administered dose per ml which closely paralleled the levels detected in blood. NNK is readily converted in vivo to 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL). The sum of NNK and NNAL was similar in the blood and milk of treated dams. There was, however, a major difference in the ratio of NNAL/NNK as detected in milk and blood. The ratio of NNAL/NNK in blood ranged from 1.3:1 to 1.9:1 while the ratio in milk ranged from 2.4:1 to 3.3:1. In a comparative study of the levels of NNN in the blood and milk of lactating rats at less than 1.0, 20, 60, 120 and 240 min after administration, it was confirmed that similar concentrations of NNN are present in blood and milk 1 h after administration. These data indicate that these carcinogens, which are present in both cigarette smoke and tobacco, can be transferred into the milk of lactating rats.

Animals↗
PubMed1987

Bowel flora changes in humans receiving cefixime (CL 284,635) or cefaclor.

Twelve healthy young male subjects received either cefixime, a new oral cephalosporin (CL 284,635), or cefaclor (six subjects on each drug) orally for 2 weeks. In the case of cefixime, single daily doses of 400 mg were taken; with cefaclor, the dosage was 250 mg three times daily. Modest changes in the fecal flora were noted in both drug groups, but the changes were of different types. In the case of cefixime, there was more of an impact on the indigenous flora, and in the case of cefaclor, there was more ingrowth of new flora. With cefixime, Enterobacteriaceae were usually decreased (the decrease in Escherichia coli count was statistically significant), as were counts of clostridia and sometimes Bifidobacterium spp.; the Bacteroides fragilis group was eliminated in one subject. Coincident with these decreases, four subjects had increases in counts of group D streptococci of 3 logs or more. There was new appearance of Clostridium difficile in four subjects and of Staphylococcus aureus in one; four new strains of Enterobacteriaceae appeared. With cefaclor, there was no decrease of E. coli counts; two subjects had elimination of Bifidobacterium spp. There was little change in counts of group D streptococci. On the other hand, there were 13 new strains of Enterobacteriaceae, two of S. aureus, and three of C. difficile.

Bacteria↗
PubMed1986

Toxicity studies on clove cigarette smoke and constituents of clove: determination of the LD50 of eugenol by intratracheal instillation in rats and hamsters.

Eugenol, eugenol acetate, beta-caryophyllene, and alpha-humulene are constituents of clove and clove cigarette smoke. The toxicity of these compounds was evaluated by intratracheal instillation in male F-344 rats. Eugenol was most toxic in this assay. The LD50 of eugenol was 11 mg/kg in male F-344 rats and 17 mg/kg in male Syrian golden hamsters. Congestion of the lung with interstitial hemorrhages, acute emphysema, and acute pulmonary edema were among the macroscopic and histologic findings observed in the animals after intratracheal administration of eugenol. Similar effects were not observed with male Syrian golden hamsters exposed to clove cigarette smoke. The estimated daily intake of eugenol for those hamsters exposed to clove cigarette smoke was below 2 mg/kg.

Animals↗