[Organotropic carcinogenic effects of 65 various N-nitroso- compounds on BD rats].

Publisher Summary This chapter provides an overview of some of the relevant chemistry (general chemistry, preparation methods, and analytical methods) of the nitroso carcinogenic compounds and discusses the pathological lesions induced by these compounds and their mutagenic activity. Experimental studies on compounds like dimethylnitrosamine showed that they cause liver necrosis in rats, accompanied by hemorrhages into the liver and lungs and frequently an associated hemorrhagic ascites and blood in the lumen of the gut. Acute toxicity of other dialkyl and related nitrosamines cause liver damage, hemorrhagic lung lesions, convulsions, and coma. The neoplastic changes in the body organs (live, kidney, bladder, nose and nasal sinuses, lungs and bronchi, alimentary canal, nervous system, and skin) and the development of the malignant lesion caused by carcinogenic nitroso compounds are also illustrated in the chapter with the help of animal models. The variation in the response of different organs to the carcinogenic nitroso compounds is of interest in relation to the biochemical changes that may be essential for the initiation of a carcinogenic change. Many carcinogenic nitroso compounds are mutagenic. The nitroso mutagens act by the alkylation of the genetic material. The chapter also discusses the metabolism of nitroso carcinogens both in vivo and in vitro, along with their biochemical effects. The induction of cancers by single doses of rapidly eliminated nitroso carcinogens implies an interaction between the carcinogen and/or a product of its decomposition with some component or components of the cells, which must occur within a short time after administration. The nature of the proximate carcinogen and some of its possible interactions with cellular components and some serious carcinogenic hazards caused by the nitroso compounds are also discussed in the chapter.

Carcinogenic Nitroso Compounds

Guidelines for Canadian Drinking Water Quality

The term renal cell tumors (adenomas and carcinomas) subsumes the tumors deriving from the uriniferous tubule epithelium of the kidney. Precise analysis shows that the renal cell tumors display different cell types which build up the individual tumor alone or in combination with each other. Three categories of basic elements are distinguished in the characterization of renal cell tumors: Cytological elements = tumor cell types: Clear, chromophobe, chromophilic (basophilic, eosinophilic), oncocytic, spindle-shaped/pleomorphic. Histological elements = growth patterns: Compact, acinar (nest-like), tubulopapillary (tubular, papillary), cystic. Cytological grading of malignancy: G I, G II, G III; mainly based on the degrees of nuclear atypia. The cytological features are given priority compared to the histological growth forms for classification of renal cell tumors. However, the latter are not to be neglected in the overall evaluation of a tumor. A classification of renal cell tumors is suggested and the result of its application in 510 renal cell carcinomas and oncocytomas is presented. On this basis and in connection with the cytological grading, a more precise prognostic evaluation of the renal cell carcinomas is expected.

Histopathology and classification of renal cell tumors (adenomas, oncocytomas and carcinomas). The basic cytological and histopathological elements and their use for diagnostics

J. M. Barnes

Papers

Induction of kidney tumours in the rat with dimethylnitrosamine (N‐nitrosodimethylamine)

The experimental production of œdema in the central nervous system of the rat by triethyltin compounds

Experimental demyelination with organo-phosphorus compounds.

The biliary and hepatic lesion produced experimentally by dibutyltin salts.