PubMed Health⌕ Search

Biomedical subjects

F Pott

Publications and source records attributed to F Pott.

At least 91 records · Page 5Linked to original sources
PubMed1976

Polycyclic aromatic hydrocarbons in human bronchial carcinoma.

A study was made to determine whether and to what extent polycyclic aromatic hydrocarbons (PAH) are present in human bronchial carcinoma. Twenty-four carcinomas, obtained from surgical operations and autopsies, were examined. The samples were tested for 12 PAH; these were determined by direct fluorescence analysis on thin-layer plates. Only 4 of the 12 PAH were detected in the cancerous tissue: benzo(a)pyrene, fluoranthene, benzo(ghi)perylene. Beno(a)pyrene was found in all carcinomas. The reasons for increased concentration of the detected PAH in cancerous tissue are discussed with respect to deposition and elimination of inhaled particles as well as the metabolism of these compounds.

Aged↗
PubMed1976

[Results of animal experiments concerning the carcinogenic effect of fibrous dusts and their interpretation with regard to the carcinogenesis in humans (author's transl)].

After reviewing the hypotheses about the pathogenesis of asbestos-induced malignant tumours we report about experimental data on animals. A high incidence of tumours (most of them mesotheliomas) was induced in rats by intraperitoneal injection of fibrous dusts (chrysotile, palygorscite, crocidolite, glass fibres, nemalite). Treatment with 8 types of granular dusts led though applicating a high dosage (50--100 mg) to neoplasms in only a small percentage of animals. After intraperitoneal application of 2 mg of chrysotile, crocidolite or glass fibres a tumour incidence in a range from 16% to 38% was observed and fibrous reaction was slight. 100 mg of milled chrysotile with relative short fibres (99.8% less than 5 mum, 99.5% less than 3 mum) caused no asbestosis, nevertheless tumours developed in 32% of the rats. Intraperitoneal injection of fibrous dusts also induced mesotheliomas in mice, however not in Syrian hamsters and guinea pigs. Our results point out that the fibrous shape of asbestos dust causes its carcinogenic effect and that furthermore other fibrous dusts can also lead to tumours. Prerequisites are an adequate measure of the fibres and their constancy in the tissue. For these two parameters no exact dates exist. It is estimated that a fibre with a diameter less than 1 mum and a length less than 3 mum exert a cancerogenic effect. Furthermore, a sequence of other factors has an importance for the dose-effect relationship of fibrous dusts. Material of the fibres plays a role in so far it defines the effect producing amount of fibres. The relevance of the results of animal experiments to man is discussed especially with regard to the cancerogenic effect of glass fibres.

Animals↗
PubMed1976

[An animal experimental study on the retention rate of polycyclic aromatic hydrocarbons in the lung and in the subcutaneous tissue (author's transl)].

The retention rate of five polyaromatic hydrocarbons (PAH) (benzo(a)pyrene, dibenz(ah)anthracene, chrysene, pyrene, benz(a) anthracene) was studied after intratracheal instillation into syrian hamsters and subcutanous injection into mice. For subcutanous injection the PAH were solved in 0.5 ml tricaprylin, for intratracheal instillation a suspension in NaCl was used. The results were the following: 1. With respect to the retention rate of the five PAH the largest difference was found comparing the application modes. The ratio of the averaged half-time-values for the intratracheal test to the subcutanous test is about 1:35. 2. The retention rates for each polycyclic hydrocarbon differs significantly. An interrelation of PAH after application of a PAH-mixture was not detectable. 3. The retention rates determined in the lung and in the subcutanous tissue do not give a constant ratio concerning each PAH. Thus DBahA is retained in the lung as well as in the subcutanous tissue definitely longer than BaP. Chrysene and benz(a)anthracene behave - respecting the retention rate - in the subcutanous test like BaP. In lung tissue, however, the different behaviour becomes obvious: while benz(a)anthracene is eliminated most rapidly, chrysene can be detected for a relative long time.

Animals↗
PubMed1974

Tumorigenic effect of fibrous dusts in experimental animals.

Fibrous dusts (chrysotile, glass fibers, nemalite, palygorscite, and gypsum) and granular dusts (actinolite, biotite, hematite, pectolite, sanidine, and talcum) were injected intraperitoneally into rats. The fibrous dusts (other than gypsum) resulted in a high incidence of mesothelioma (30 - 67%). Gypsum produced only 5% and granular dusts none at all. It is suggested that the fibrous shape leads to a high multiplication rate of cells and predisposes to tumor formation. Fibrosis, in the other hand, does not so predispose. Milled chrysotile with 99.8% fibers than 5 mum in length are carcinogenic in our experience. The carcinogenicity of glass fibers in our experiments may have significance for occupational situations.

Abdominal Neoplasms↗