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Biomedical subjects

B Toth

Publications and source records attributed to B Toth.

At least 55 records · Page 3Linked to original sources
PubMed1983

Enhancing effect of vitamin E on murine intestinal tumorigenesis by 1,2-dimethylhydrazine dihydrochloride.

The effect of the antioxidant vitamin E on the tumor-inducing ability of 1,2-dimethylhydrazine dihydrochloride (1,2-DMH) was investigated in randomly bred Swiss mice. Three groups of mice that were 6 weeks of age at the beginning of the experiment received the following treatments: a) vitamin E acetate [DL-alpha-tocopheryl acetate (TA)] at a 4% dose level in a powdered diet for life; b) 1,2-DMH, 10 weekly sc injections at 20 micrograms/g body weight; c) combination of a and b treatments. The administration of TA enhanced the tumorigenicity of 1,2-DMH, as evidenced by statistically significant incidences of tumors in the duodenum, cecum, colon, rectum, and anus. The present finding apparently is in contrast with the reported inhibitory effect of TA on colon carcinogenesis by 1,2-DMH.

1,2-Dimethylhydrazine↗
PubMed1983

Tumorigenic action of repeated subcutaneous administration of N-methyl-N-formylhydrazine in mice.

N-Methyl-N-formylhydrazine (MFH), an ingredient of the edible false morel mushroom, was administered to Swiss mice as 40 weekly subcutaneous injections at 20 micrograms/g body weight for females and 10 micrograms/g body weight for males. The treatments gave rise to statistically significant incidences of lung tumors: 56% in females and 40% in males. The administration of the chemical resulted in no detectable carcinogenic effect in other organs. The findings are discussed in light of the results from earlier studies with this compound.

Animals↗
PubMed1982

Tumorigenicity of minute dose levels of N-methyl-N-formylhydrazine of Gyromitra esculenta.

Separate administrations of 0.0005 to 0.00025% N-methyl-N-formylhydrazine in drinking water to 6-week-old randomly bred Swiss mice for the remainder of their lifetime induced lung neoplasms. At the high dose level, 64% of the females and 48% of the males developed lung tumors, while the corresponding tumor incidences at the lower dose level were 62% in the females and 54% in the males. In untreated controls, the lung tumor incidences were 29% in the females and 19% in the males. Histopathologically, the lesions were classified as adenomas and adenocarcinomas of the lungs. N-methyl-N-formylhydrazine is a stable constituent of the edible false morel mushroom Gyromitra esculenta. The environmental significance is discussed, in view of the carcinogenicity of minute doses of this chemical.

Adenocarcinoma↗
PubMed1982

Microbial mutagenicity of selected hydrazines.

Selected hydrazines and related compounds were examined for their mutagenic activity in S. typhimurium strains TA1535 and TA1537. These in vitro assays were conducted with and without metabolic activation by Aroclor-induced rat-liver enzymes. Relatively high levels of mutagenicity were observed with phenylhydrazine X HCl, methylhydrazine, N'-acetyl-4-(hydroxymethyl)phenylhydrazine, and 4-(hydroxymethyl)benzenediazonium tetrafluoroborate, the stabilized salt of a carcinogenic metabolite of agaritine; only low levels of mutagenicity were observed with other compounds, although most are strong carcinogens. Several of the compounds were highly toxic to the bacteria, and detection of mutagenicity was enhanced by calculating the increase in mutagenic activity on the basis of the surviving fractions of bacteria.

Animals↗
PubMed1982

Occurrence, stability and decomposition of beta-N [gamma-L(+)-glutamyl]-4-hydroxymethylphenylhydrazine (agaritine) from the mushroom Agaricus bisporus.

A chromatographic technique was developed that could clearly separate beta-N [gamma-L(+)-glutamyl]-4-hydroxymethylphenylhydrazine (agaritine) from all other components in 10-500-microliters samples of mushroom extracts. Locally purchased mushrooms were found to contain mean levels of 0.4 - 0.7 mg agaritine g. The agaritine content of the mushrooms had decreased by 2-47% after 1 wk of storage in a domestic refrigerator and by 36-76% after 2 wk of such storage. Canned mushroom soup and canned mushrooms did not contain detectable agaritine; a sample of frozen mushrooms contained a mean level of 0.33 mg/g and a batch of fresh mushrooms lost about 32% of their agaritine content on cooking. In mice given 3 mg agaritine by gavage, agaritine was detected in all parts of the gastro-intestinal tract 15 min after dosing, but none was detectable in the gut after 3 hr. The enzyme gamma-glutamyltranspeptidase derived from pig's kidney was found to be capable of decomposing agaritine to glutamic acid and 4-(hydroxymethyl)phenylhydrazine, and to have nine times such activity as an enzyme isolated from mushrooms.

Agaricales↗
PubMed1982

Gastric tumorigenesis by a single dose of 4-(hydroxymethyl)benzenediazonium ion of Agaricus bisporus.

4-(Hydroxymethyl-benzenediazonium tetrafluoroborate was administered as a single intragastric instillation at 400 micrograms/g to Swiss albino mice. The treatment gave rise to glandular stomach tumours in incidences of 30% in females and 32% in males. Histopathologically, the tumours were classified as polypoid adenomas and adenocarcinomas. This diazonium ion is an ingredient of the cultivated mushroom of commerce, Agaricus bisporus. The implications are self-evident.

Adenocarcinoma↗
PubMed1982

1,2-diallylhydrazine dihydrochloride carcinogenesis in mice.

Continuous administration of 0.0625% 1,2-diallylhydrazine dihydrochloride in drinking water for life to 6-week-old randomly bred to Swiss mice induced lung tumors. In comparison with the untreated controls, the lung tumor incidence rose from 25 to 80% in the females and from 26 to 80% in the males. The treatment had no apparent effect on the development of other tumor types. Histopathologically, the lesions were classified as adenomas and adenocarcinomas of the lungs. The work is a continuation of our structure activity inquiry concerning the relative carcinogenic potencies of the dialkyl versus the monoalkyl series of hydrazine analogues.

Adenocarcinoma↗
PubMed1981

Carcinogenicity of the environmental pollutants cyclopenteno-[cd]pyrene and cyclopentano[cd]pyrene in mouse skin.

Cyclopenteno[cd]pyrene (CPEP) is a widespread environmental pollutant. This hydrocarbon and its 3,4-dihydro derivative, cyclopentano[cd]pyrene (CPAP), were tested on skin in a two-stage initiation-promotion experiment in CD-1 mice and by repeated application in Swiss mice. The biological effect of CPEP and CPAP was compared to that of benzo[a]-pyrene (BP). Nine-week-old female CD-1 mice in groups of 30 were treated every other day over a 20-day period at mini-dose levels of 0.18, 0.06 and 0.02 mumol of CPEP or CPAP in acetone. One group was treated with BP at the low mini-dose level. Initiation was followed by twice weekly application of tetradecanoyl phorbol acetate for 40 weeks. In the second experiments, nine-week-old female Swiss mice in groups of 30 were treated at dose levels of 1.8, 0.6 and 0.2 mumol CPEP or CPAP in acetone twice weekly for 30 weeks. One group was treated with BP at the low dose. CPAP was virtually inactive in both studies. In the initiation-promotion experiment CPEP was inactive at the low dose level, whereas BP exhibited significant tumorigenicity. At the medium and high doses CPEP showed weak, but statistically insignificant, tumorigenic activity. Repeated application of CPEP at the high, medium and low doses resulted in tumor incidences of 23, 37 and 57%, respectively. This reverse dose-response may be due to the relatively high cytotoxicity of CPEP, BP, which was compared to CPEP at the low dose, elicited tumors in 100% of the mice. Most of the CPEP-induced neoplasms were malignant and some metastasized to lungs and lymph nodes. The inactivity of CPAP suggests the carcinogenicity of CPEP is probably due to formation of the ultimate metabolite CPEP 3,4-oxide. In view of the abundance of CPEP in environmental and occupational pollutants, its moderately potent carcinogenicity may represent a potential health hazard.

Animals↗
PubMed1981

Carcinogenic effects of 1,1-di-n-butylhydrazine in mice.

Lifetime administration of 0.03125% 1,1-di-n-butylhydrazine in drinking water to Swiss mice, from 6 weeks of age, induced tumors of the lungs, forestomach and liver. The tumor incidences in these tissues in untreated controls were 25, 2 and 0.5%, whereas in the treated groups the corresponding tumor incidences increased to 68, 39 and 5%, respectively. Histopathologically these lesions were classified as adenomas and adenocarcinomas of the lungs, squamous cell papillomas and carcinomas of the forestomach, and benign hepatomas and liver cell carcinomas. The work is part of a structure activity inquiry and its specific aim is to disclose whether the dialkyl derivatives of hydrazine are more active carcinogens than the monoalkyl analogues.

Animals↗
PubMed1981

Nicotinic acid hydrazide carcinogenesis in mice.

Nicotinic acid hydrazide was administered as a 0.125% solution in drinking water continuously for life from 6 weeks of age to randomly bred Swiss albino mice. As a result of treatment, the lung tumor incidence rose from 25 to 76% in females and from 26 to 42% in males. The treatment had no statistically significant effect on the development of other types of tumors. Histopathologically the tumors were classified as adenomas and adenocarcinomas of the lungs. The study thus demonstrates the tumorigenicity of this compound which is a structural homologue of the tuberculostatic and carcinogenic isonicotinic acid hydrazide.

Adenocarcinoma↗
PubMed1981

Cancer induction in mice with acetaldehyde methylformylhydrazone of the false morel mushroom.

Acetaldehyde methylformylhydrazone (AMFH), which occurs up to 0.3% in one of the edible false morel mushrooms, Gyromitra esculenta, was administered to noninbred Swiss mice in propylene glycol in 52 weekly intragastric instillations as 100 micrograms/g body weight. The treatment induced tumors of the lungs, preputial glands, forestomach, and clitoral glands. The tumor incidences in these four tissues in treated females were 70, 0, 16, and 12%, respectively, whereas in the treated males they were 40, 90, 0, and 0%. The corresponding tumor incidences in the solvent control females were 26, 0, 0, and 0%, whereas in the solvent control males they were 22, 0, 0, and 0%, respectively. Histopathologically, the neoplasms were classified as adenomas and adenocarcinomas of the lungs; squamous cell papillomas and carcinomas, adenocarcinomas, undifferentiated carcinomas, angiosarcomas, and fibrosarcomas of the preputial glands; squamous cell papillomas and carcinomas of the forestomach; and squamous cell papillomas and carcinomas and keratoacanthomas of the clitoral glands. The study thus proves for the first time the tumorigenicity of AMFH. In view of these and earlier findings, the human population should abstain from consumption of Gyromitra esculenta.

Acetaldehyde↗
PubMed1981

Carcinogenesis of 4-(hydroxymethyl)benzenediazonium ion (tetrafluoroborate) of Agaricus bisporus.

4-(Hydroxymethyl)benzenediazonium tetrafluoroborate was administered as 26 weekly s.c. injections of 50 microgram/g body weight to randomly bred Swiss mice. In addition, as a solvent control, sodium tetrafluoroborate was given as 26 weekly s.c. injections at 25 microgram/g body weight in 0.9% NaCl solution to another group of mice. The 4-(hydroxymethyl)benzenediazonium tetrofluoroborate treatment induced tumors in the subcutis and skin in incidence of 20 and 12%, respectively; while in the solvent sodium tetrafluoroborate-injected mice, the corresponding tumor incidence were 6 and 0%, respectively. Histopathologically, the tumors were classified as a fibroma, fibrosarcomas, rhabdomyosarcomas, and an angiosarcoma in the subcutis and also as squamous cell papillomas and carcinomas of the skin. 4-(Hydroxymethyl)benzenediazonium ion is an ingredient of the cultivated mushroom of commerce Agaricus bisporus.

Animals↗
PubMed1981

Gyromitrin as a tumor inducer.

Acetaldehyde methylformylhydrazone (gyromitrin) was administered in propylene glycol as 12 weekly subcutaneous injections of 50 micrograms/g weight to randomly bred Swiss mice. The treatment induced lung and preputial gland tumors in incidences of 51 and 0% in females and 46 and 28% in males, respectively. In the propylene glycol injected control groups, the corresponding tumor incidences were 28 and 0% in females and 32 and 0% in males. Histopathologically, the tumors were classified as adenomas and adenocarcinomas of the lungs and squamous cell papillomas and carcinomas and adenocarcinomas of preputial glands. Gyromitrin is an ingredient of the wild edible false morel mushroom Gyromitrin esculenta. The environmental significance of the findings is discussed.

Acetaldehyde↗
PubMed1981

Attempted tumor induction with agaritine in mice.

Agaritine, a constituent of the cultivated mushroom of commerce Agaricus bisporus, was administered at concentrations of 0.0625 and 0.03125% in drinking water daily for life to randomly bred Swiss mice. Consumption of the chemical resulted in no detectable carcinogenic action under the experimental conditions. During the course of the experiment, however, a substantial number of animals developed convulsive seizures.

Adenocarcinoma↗
PubMed1981

[Congenital heart diseases and pregnancy (author's transl)].

The maternal foetal prognosis was studied on the basis of data which had been recorded from 56 pregnancies or deliveries of 46 women with congenital cardiac defects. Functional changes of circulation, such as hypoxia, pressure and volume overload, and conduction disorders, were assessed, with reference being made to the classification of the American Heart Association (AHA). In that context, the patients were repeatedly examined during pregnancy and followed up further through two years after delivery. --Maternal prognosis in pregnancy and, consequently, oxidation were found to depend on the kind of congenital heart disease. Reference is made to the favourable role played by cardiac surgery in preventing cardiac complications. Premature birth and retarded foetal development have occurred repeatedly, depending on severity of a congenital heart disease. Enzymological-histological tests are likely to suggest that such consequences were primarily attributable to strongly impaired placental energy production on account of inadequate haemodynamic conditions of the mother. --Proper prognostication of pregnancy will depend for high standards on adequate supervision of delivery, prophylactic use of caesarean section, individual assessment of any single case, and efficient teamwork of obstetricians and cardiologists.

Adult↗
PubMed1981

Tumorigenesis with 1,1-diallylhydrazine in mice.

1,1-Diallylhydrazine was administered as a 0.03125% solution in drinking water for life to Swiss mice, from 6 weeks of age. Compared to untreated controls, in treated animals the lung tumor incidence rose from 25 to 76% in females and from 26 to 76% in males, whereas the incidence of forestomach tumors increased from 4 to 14% in females and from 0 to 34% in males. Histopathologically, the tumors were classified as adenomas and adenocarcinomas of the lungs and squamous cell papillomas and carcinomas of the forestomach. This work is part of our structure activity inquiry and demonstrates the relative carcinogenic potency of another disubstituted allylhydrazine.

Adenocarcinoma↗