[Agents for the aerosol disinfection of the air in meat freezers]. / Prouchvaniia vurkhu niakoi sredstva za aerozolna dezinfektsiia na vuzdukha v khladilnitsite na meso.

Studies were carried out on the use of aerosol disinfection with lactic acid and sorbic acid at rates of 15, 30, and 50 mg per 1 m3 air in chambers for the conservation of meat and meat products at temperatures within the range of 0 to 2 degrees C. Moulds of the Penicillium genus and psychrophile organisms (Pseudomonas, Alkaligenes, and Flavobacter) were used as test microbial species. It was found that the disinfection effect of lactic acid used in the form of aerosol was the same as that of sorbic acid when psychorophiles served as test bacteria, and was essentially better in the disinfection of the air in refrigerators and the surface of meat when Penicillium moulds were used. In concentrations of up to 50 mg/m3 both lactic acid and sorbic acid had no adverse effect on the organoleptic indices of meat during refrigerator storage.

Cytocaryometric characteristics of carcinomas of the human breast.

By means of a graduated microscope eyepiece-micrometer, karyometric investigations were carried out on cytological smears from 21 patients with breast cancer (adenocarcinoma--7, scirrhous--5, medullar--3, intraductal--3, and undifferentiated--3). In breast cancer, the number of the cell groups was high; the karyometric histograms were multi-peaked, without well expressed peaks, shifted to the right and the nuclear sizes were large. The mean nuclear area and volume were the largest in undifferentiated carcinoma and adenocarcinoma, and they were the smallest in scirrhous carcinoma (the mean area) and in intraductal carcinoma (the mean volume).

[Carcinogenic action of diarsenic trioxide]. / Vurkhu kantserogennoto deistvie na dvuarsenoviia triokis.

Biarsenic trioxide under the experimental conditions outlined in the paper causes mainly adenopapillomatous proliferations in the intestine and partly in the stomach, as well as adenomatous proliferations in the lungs, all of which may be considered as precancerous conditions. Having in mind that no cancerigenic actions of arsenic has been proved hitherto, the experimental data submitted assume a particular theoretical and practical interest.

Geographic correlation between the occurrence of endemic nephropathy and urinary tract tumours in vratza district, Bulgaria.

Data on the occurrence of endemic nephropathy (EN) and urinary tract and other cancers in an endemic region of Vratza district, Bulgaria, for the years 1965-1974, are presented. In endemic villages a high incidence of urinary tract tumours, affecting in particular the renal pelvis and ureter, closely correlated with the EN incidence and mortality rates. In the villages with high and moderate EN incidences urinary tract tumours are the most common neoplasms. They account for 25% of all tumour sites in males and 30% in females. In hyperendemic villages age-adjusted incidences in EN and urinary tract tumours were 506/10(5) and 104/10(5) in females, and 315/10(5) and 89/10(5) in males respectively. EN mortality in these villages accounted for over 40% of all deaths in females and about 30% in males. Both diseases displayed peculiar geographic clustering. Females and middle-aged persons were most often affected. Urinary tract neoplasms were often multiple and nearly 90% of them originated in the uro-epithelium. In endemic and non-endemic villages of the region studied, the frequency and pattern of non-urinary tract cancers were rather similar, with statistical values close to those of the rural population of Vratza District and Bulgaria as a whole.

Cancer mortality in a region with endemic nephropathy.

Cancer mortality in endemic and non-endemic villages from a region with endemic nephropathy (EN) of Vratza district, Bulgaria has been compared for the period 1965--1974. The total and for all cancer sites mortality rates in all studied villages were comparable to European and world standards except a very high mortality from tumors of urinary organs in the endemic villages. Age-adjusted to world population rates/10(5) population in hyperendemic villages have been estimated as 16.8 for males and 14.9 for females in case of kidney tumors and as 7.1 in males and 10.2 for females in case of urinary bladder tumors. On village group basis a very close correlation between mortality rates from urinary system tumors and EN incidence rates has been disclosed although endemic and non-endemic villages are neighbouring and are very similar in ecological and cultural terms.