[Photolysis of aflatoxin B1 in the presence of pyridine N-oxide]. / Fotoliz aflatoksina B1 v prisutstvii N-okisi piridina.

Aflatoxin B1 (AFB1) photolysis in presence of pyridine N-oxide was studied. It was established that AFB1 ethanol solution irradiated with UV-light lambda = 362 nm demonstrated an increase of the fluorescence as a result of appearance of AFB1 product which was formed by pyridine N-oxide oxygen binding to AFB1 molecules in position 2,3.

[Microsomal and photochemical oxidation of aflatoxin B1]. / Mikrosomal'noe i fotokhimicheskoe okislenie aflatoksina B1.

The UV irradiation (lambda = 362 nm) of aflatoxin B1 (AfB1) dissolved in water resulted in the formation of an oxidized product. The process was not inhibited by ionol, a routine inhibitor of the radical processes. The oxidized product was not found in the system where AfB1 was metabolized by the 3-methylcholanthrene-activated rat liver microsomes. It is suggested that the product is identical with 2,3-dihydrodiol of AfB1.

[Progression of new transplantable hepatomas in C3HA strain mice. I. 61EP hepatomas]. / Progessiia novykh perevivaemykh gepatom myshei linii C3HA. I. Gepatomy 61EP.

Three new morphologically different strains of stabilized transplantable hepatomas in C3HA mice were obtained using continuous transplantation of nitrosodiethylamine induced primary liver tumour by the method of parallel sublines. Morphology and development of biological properties of substrains of hepatomas are described. All differences between substrains arose gradually throughout a number of generations, with malignization of hepatomas occurring. If the development of hepatomas was accompanied with differentiation, as was the case in some substrains in our experiments, the rate of a successful transplantation diminished, and it was impossible to obtain stabilized strains of transplantable hepatomas.

[Progression of new transplantable hepatomas in C3HA strain mice. II. Hepatomas 1676]. / Progressiia novykh perevivaemykh ge patom myshei linii C3Ha. II Gepatomy 1676.

Seven new morphologically different strains of stabilized transplantable hepatomas were obtained, using a continuous subcutaneous transplantation of a highly differentiated orthoaminoazotoluol-induced primary hepatoma by the method of parallel sublines. Morphology and biological properties of all substrains are described. Differences between substrains of the highly differentiated primary hepatoma, according to their biological properties and morphology, were greater than those between substrains obtained by transplantation of a lowly differentiated primary hepatoma as a parent tumour. Some aspects of differentiation of hepatomas during their progression and stabilization are discussed.

[Changes in the endomembrane system and mitochondria of cultured chick fibroblasts upon application of colchicine and following its withdrawal]. / Izmenenie éndomembrannoi sistemy i mitokhondrii v kul'tiviruemykh kurinykh fibroblastakh pri deistvii kolkhitsina i posle ego udaleniia. Morfometricheskii analiz.

After the administration of colchicine (5 mcg/ml) into nutritive medium of primary tissue culture there is a remarkable decrease in the volume and number of fibroblast-membrane organoids during the first 3 hours. The removing of colchicine-damaged fibroblasts into the medium without colchicine leads to the renewal of the most of intracellular membranes during the following 24 hours. Probable reasons and mechanisms of colchicine-induced alterations are discussed.