Search PubMed⌕ Search

Biomedical subjects

B Toth

Publications and source records attributed to B Toth.

At least 73 records · Page 4Linked to original sources
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↗
PubMed1980

Actual new cancer-causing hydrazines, hydrazides, and hydrazones.

Twenty actual new cancer-causing hydrazines, hydrazides, and hydrazones of synthetic or natural origin are described. These compounds induce tumors in various target tissues in mice, hamsters and rats. To nine of these compounds the human population is exposed in the form of drugs, agricultural herbicides, and naturally occurring ingredients of edible mushrooms. Yet, with one exception, none of the hydrazines described here were investigated for cancer-inducing abilities in man. The human population should be warned against the use of this hazardous class of chemicals, the total number of which is now 40.

Animals↗
PubMed1980

Tumorigenesis by N-n-propyl-N-formylhydrazine in mice.

Continuous administration of 0.04% N-n-propyl-N-formylhydrazine (PFH) for life in drinking water to 6-week-old randomly bred Swiss mice induced tumours of the lungs, preputial glands, liver and gallbladder. The tumour incidences in these 4 tissues were 91, 22, 8 and 6%, whereas in the untreated controls they were 25, 0, 0.5 and 0.5%, respectively. The higher dose of 0.08% PFH, given under identical conditions, induced only tumours of the lungs, liver and gall bladder in low incidences, since the compound was too toxic for the mice. Histopathologically, the tumours were classified as adenomas and adenocarcinomas of the lungs, squamous-cell papillomas, and carcinomas and fibrosarcoma of preputial glands, benign hepatomas and liver-cell carcinoma, as well as adenomas and adenocarcinoma of the gall bladder. The investigation is part of our structure/activity relationship inquiry aimed at revealing the mechanism of action of the N-alkyl-N-formylhydrazine series of chemicals.

Animals↗
PubMed1980

Carcinogenesis by a single dose of N-methyl-N-formylhydrazine.

Single sc injections of N-methyl-N-formylhydrazine were given to randomly bred Swiss mice. The females received 180 micrograms per gram of body weight, while two groups of males were treated with either 120 or 100 micrograms per gram of body weight. The treatment resulted in induction of tumors of lungs with an incidence of 40% in the females. In males treated with the higher and lower doses, the incidences of preputial gland tumors were 12 and 12%, respectively. Histopathologically, the tumors were classified as adenomas and adenocarcinomas of lungs, squamous cell papillomas, and carcinomas of preputial glands. N-Methyl-N-formylhydrazine is a constituent of the edible wild false morel mushroom Gyromitra esculenta, to which the human population is exposed in measurable quantities, sometimes at a single meal.

Adenocarcinoma↗
PubMed1980

Tumorigenic action of N-n-butyl-N-formylhydrazine in mice.

Continuous administration of 0.04% N-n-butyl-N-formylhydrazine (BFH) in drinking water to 6-week-old randomly bred Swiss mice for life produced tumors of the lungs, preputial and clitoral glands. The tumor incidences in these three tissues of the treated animals were 87, 66, and 10%, whereas in the untreated controls they were 25, 0, and 0%, respectively. Histopathologically, the tumors were classified as adenomas and adenocarcinomas of the lungs, squamous cell papillomas and carcinomas, angio-, fibro-, and myxo- sarcomas of preputial glands and squamous cell papillomas and carcinomas of clitoral glands. N-n-Butyl-N-formylhydrazine is a structural homologue of the carcinogenic N-methyl-N-formylhydrazine and N-ethyl-N-formylhydrazine. These studies are integral parts of structure activity relationship inquiries.

Animals↗
PubMed1980

Tumorigenesis by benzo(a)pyrene administered intracolonically.

Benzo(a)pyrene (BP) was administered to Swiss mice in 1 and 10 weekly intracolonic instillations at 200 microgram/g body weight. The single administration of BP induced a statistically significant incidence of malignant lymphomas and tumors of the forestomach, while its repeated instillation, evoked, in addition to these two tumor types, neoplasms in the esophagus, anus and skin. BP failed to elicit intestinal tumors, which was the main objective of the present investigation. We discuss, in light of the obtained results, the various experimental conditions under which studies were conducted of this most versatile and widely occurring carcinogen, to which a large segment of the human population is exposed.

Animals↗
PubMed1980

The tumorigenic effect of low dose levels of N-methyl-N-formylhydrazine in mice.

Solutions of 0.002 and 0.001% N-methyl-N-formylhydrazine (MFH) were given separately daily in drinking water to 6-week-old randomly bred Swiss mice for life. The treatments resulted in induction of tumors of the lungs, blood vessels, liver and gall bladder. The 0.002% solution gave rise to tumors of the above tissues in incidences of 76, 27, 28 and 11%, respectively, while the 0.001% solution induced tumors in incidences of 75, 23, 7 and 6%. Histopathologically, the neoplasms were adenomas and adenocarcinomas of lungs, angiomas and angiosarcomas of blood vessells, benign hepatomas, liver cell carcinomas and adenomas and adenocarcinomas of the gall bladder. MFH is an ingredient of the edible mushroom, the false morel Gyromitra esculenta. The present study proves the carcinogenicity of MFH administered at low dose levels. The possible environmental significance of the findings to the human population is discussed.

Animals↗
PubMed1979

False morel mushroom Gyromitra esculenta toxin: N-methyl-N-formylhdrazine carcinogenesis in mice.

N-Methyl-N-formylhydrazine was administered in drinking water as a 0.0039% solution to randomly bred Swiss albino mice for life starting from 6 weeks of age. The compound induced tumors of lungs, livers, blood vessels, gall bladder and bile ducts. The tumor incidences in these five tissues were 77, 46, 21, 10 and 7% while in the untreated controls they were 18, 1, 6, 0 and 0% respectively. Histopathologically, the tumors were classified as adenomas and adenocarcinomas of lungs, benign hepatomas and liver cell carcinomas, angiomas and angiosarcomas of blood vessels, adenomas and adenocarcinomas of gall bladder and cholangiomas. The macroscopic and light microscopic involvement of the tissues with the tumors are described and some of them are illustrated. N-Methyl-N-formylhydrazine is an ingredient of the edible mushroom, the false morel Gyromitra esculenta. The findings are discussed from the viewpoint of a potential human health hazard.

Animals↗
PubMed1979

Carcinogenic effects in the Syrian golden hamster of N-methyl-N-formylhydrazine of the false morel mushroom Gyromitra esculenta.

N-Methyl-N-formylhydrazine (MFH) was administered in drinking water as a 0.0078% solution to randomly bred Syrian golden hamsters for life beginning at 6 weeks of age. The treatment gave rise to benign and malignant liver cell tumors, malignant histiocytomas and tumors of the gall bladder and bile ducts. The tumor incidence in these four treated tissues was 43, 34, 11,8%, while in untreated controls it was 0, 0, 0, 0%, respectively. Histopathologically, tumors were classified as benign hepatomas, liver cell carcinomas, malignant histiocytomas, adenomas and adenocarcinomas of the gall bladder, cholangiomas, and cholangiocarcinomas.

Animals↗
PubMed1978

Lung tumorigenesis by 1,2-diformylhydrazine in mice.

1,2-Diformylhydrazine was administered in drinking water as a 2% solution to randomly bred Swiss albino mice for life from 6 weeks of age. As a result of treatment, the lung tumor incidence rose from 15 to 96% in females and from 22 to 82% in males. The treatment had no statistically significant effect on the development of other types of tumors. Histopathologically, the neoplasms exhibited the characteristic appearance of adenomas and adenocarcinomas of the lungs. The work is part of a series of studies aimed at revealing the relative carcinogenic potency of mono- and dialkyl-hydrazines and also their possible environmental significance as cancer causative agents.

Adenocarcinoma↗
PubMed1978

Formylhydrazine carcinogenesis in mice.

Administration of 0.125% formylhydrazine in drinking water to 6-week-old randomly bred Swiss albino mice for life, induced lung tumours. Compared to untreated controls, the lung-tumour incidence rose from 15 to 94% in the females and from 22 to 100% in the males. The treatment had no detectable tumorigenic effect in other organs.

Adenocarcinoma↗
PubMed1978

Tumors induced in mice by N-methyl-N-formylhydrazine of the false morel Gyromitra esculenta.

Continuous administration of 0.0078% N-methyl-N-formylhydrazine (MFH) in drinking water to 6-week-old outbred Swiss mice for life produced tumors of the liver, lung, gallbladder, and bile duct. The incidences of tumors in these four tissues were 33, 50, 9, and 7%, whereas in the untreated controls they were 1, 18, 0, and 0%, respectively. The higher dose (0.0156% MFH) given under identical conditions had no tumorigenic effect, since it proved too toxic for the animals. Histopathologically, the lesions were classified as benign hepatomas, liver cell carcinomas, adenomas and adenocarcinomas of the lungs, adenomas of the gallbladder, cholangiomas, and cholangiocarcinomas. Since the edible false morel Gyromitra esculenta contains a high amount of MFH, the human population should be dissuaded from consumption of this dangerous mushroom.

Animals↗
PubMed1978

Tumorigenic effect of 1-hydrazinophthalazine hydrochloride in mice.

A solution of 0.125% 1-hydrazinophthalazine hydrochloride, an antihypertensive drug widely used in humans, was given continuously in drinking water for the life-spans of randomly bred Swiss mice. Consumption of the chemical significantly increased the lung tumor incidence from 36 to 60% in females and from 26 to 46% in males, compared to controls. Histopathologically, the tumors were classified as adenomas and adenocarcinomas of the lungs.

Adenocarcinoma↗
PubMed1978

Tumor induction with the N'-acetyl derivative of 4-hydroxymethyl-phenylhydrazine, a metabolite of agaritine of Agaricus bisporus.

N'-Acetyl-4-(hydroxymethyl)phenylhydrazine was administered as a 0.0625% solution in drinking water continuously for the life span of Swiss mice, from 6 weeks of age. Compared to that in untreated controls, in treated animals the lung tumor incidence rose from 15 to 34% in females and 22 to 48% in males, whereas the incidence of blood vessel tumors increased from 8 to 32% in females and from 5 to 30% in males. Histopathologically, the tumors were classified as adenomas and adenocarcinomas of the lungs and angiomas and angiosarcomas of the blood vessels. The commonly eaten mushroom Agaricus bisporus contains beta-N-[gamma-L(+)-glutamyl]-4-hydroxymethylphenylhydrazine, which under certain conditions yields 4-hydroxymethylphenylhydrazine and L-glutamic acid. Since 4-hydroxymethylphenylhydrazine is relatively unstable, its acetyl derivative was synthesized for this study. The possible environmental significance of the findings is discussed.

Adenocarcinoma↗
PubMed1977

Tumorigenic effect of 4-methylphenylhydrazine hydrochloride in Swiss mice.

4-Methylphenylhydrazine hydrochloride was administered as 10 weekly subcutaneous injections of 140 microgram/g body weight and as 7 weekly intragastric instillations of 250 microgram/g body weight in physiological saline to randomly bred Swiss mice. Treatments given subcutaneously resulted in induction of lung tumors in incidences of 36% in females and 44% in males, while intragastric treatment caused a 40% incidence in females. In addition, it gave rise to blood vessel tumors by intragastric route in incidences of 32% in females and 18% in males. In the two physiological saline-treated control groups, the lung tumor incidence (combined) was 20% in females and 21% in males, while the blood vessel tumor incidence (combined) was 7% in females and 6% in males. Histopathologically, the lesions were classified as adenomas and adenocarcinomas of the lungs, and angiomas and angiosarcomas of blood vessels. 4-Methylphenylhydrazine was postulated to be a metabolite of 4-hydroxymethylphenylhydrazine, an ingredient of the commonly eaten mushroom Agaricus bisporus. The implications are discussed with respect to the tumorigenesis data.

Animals↗
PubMed1977

The large bowel carcinogenic effects of hydrazines and related compounds occurring in nature and in the environment.

Five substituted hydrazines that induce large bowel and other types of cancer in laboratory animals are described. Two of these compounds, which originate in nature, are 1,1-dimethylhydrazine, a tobacco ingredient, and methylhydrazine, formed from a chemical present in the edible wild mushroom Gyromitra esculenta. The human population is therefore exposed to them considerably. In addition, both compounds are manufactured and used in rocket fuel. The other three chemicals, 1,2-dimethylhydrazine dihydrochloride,1-methyl-2-butylhydrazine dihydrochloride and trimethylhydrazine hydrochloride, are manufactured synthetically only and apparently are not found in substantial quantities in the environment.

Adenocarcinoma↗