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C B Wigley

Publications and source records attributed to C B Wigley.

25 records · Page 2Linked to original sources

Different tumours induced by benzo(a)pyrene and its 7,8-dihydrodiol injected into adult mouse salivary gland.

A comparison has been made between the carcinogenic activities of benzo(a)pyrene and the proposed proximate carcinogen, benzo(a)pyrene 7,8-dihydrodiol, in the adult C57BL mouse submandibular salivary gland. In preliminary studies using a range of doses, the dihydrodiol was slightly less active than the parent hydrocarbon in this system. There was a difference in the type of tumour induced by the 2 compounds. Benzo(a)pyrene induced tumours of the salivary glands at the site of injection, whereas the dihydrodiol induced malignant lymphosarcomas, particularly of the thymus, which were often metastatic to other orgnas. Possible reasons for the different sites of action of the 2 compounds are discussed.

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Cell-mediated mutagenesis in cultured Chinese hamster cells by carcinogenic polycyclic hydrocarbons: nature and extent of the associated hydrocarbon-DNA reaction.

A system of cell-mediated mutagenesis is described for the study of compounds which require metabolic activation to exert their cytotoxic and mutagenic effects. This system combines BHK21 cells for metabolism of the compounds and V79 cells as targets for mutagenesis. Using the two polycyclic hydrocarbon carcinogens benzo(a)pyrene and 7-methylbenz(a)anthracene we have shown that the hydrocarbon-DNA reaction which accompanies mutagenesis in the target cell is indistinguishable from that reported to occur in vivo and in primary cell cultures. Our results also support the view that a diol epoxide metabolite is responsible for the biological activity of benzo(a)pyrene. The application of cell-mediated mutagenesis to the routine testing of suspect environmental chemicals for biological activity is discussed.

Azaguanine↗

Salivary epithelial cells in primary culture: characterization of their growth and functional properties.

Mouse submandibular salivary gland cells were grown in primary explant culture. After an initial period of degeneration within the explant, surviving epithelial cells proliferated rapidly and duct-like structures recolonized the explant. Autoradiographic studies showed that a peak of DNA synthesis occurred after 4 days in vitro and that proliferation was enhanced by insulin and hydrocortisone. These cells retained specialized secretory function (protease activity) for at least 2 weeks in vitro. This enzyme is a differentiated product of granular tubule cells in vivo. Between 6 and 10 days, explants attached to the substrate. An outgrowth developed, consisting largely of ultrastructurally identifiable epithelial cells which formed pseudoglandular structures in the monolayer. Epithelium survived for over 6 months in primary culture but could not be serially transferred. Secondary cultures were rapidly overgrown by mesenchymal cells.

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