[The effect of elevated amounts of ascorbic acid on the status of the vitamin and lung disorders in guinea pigs inhaling styrene]. / Vliianie na povisheni kolichestva askorbinova kiselina vurkhu statusa na vitamina i narusheniiata v beliia drob pri inkhalirani sus stirol morski svincheta.

An inhalation intoxication with styrene is performed on guinea pigs--600 mg.m-3, 5 hrs daily, 5 days weekly for a period of 4 weeks. The animals are put on regime lacking vitamin C. Ascorbic acid is introduced orally on 3 levels: 20 mg.kg-1 body mass (control) and with increased quantities 60 mg.kg-1 and 240 mg.kg-1 body mass. On the third day the content of ascorbic acid in some biochemical parameters of the lung is determined. Histochemical examinations of the lung tissue are made. The styrene causes decrease in the ascorbic acid content in the lung, considerable increase of the studied enzymes (lactate- and glucose-6-phosphate-dehydrogenase, alkaline and acidic phosphatase) and the concentration of the total protein in the lung. There are inflammatory, dystrophic and obturation changes. The raised intake of ascorbic acid 60 mg.kg-1 body mass doesn't effect the negative influence of styrene. The high dose (240 mg.kg-1 body mass) provokes increased activity of the examined enzymes. At inhalation with styrene this dose of ascorbic acid increases the styrene effect on the enzyme activity, especially of LDH and glucose-6-phosphate-dehydrogenase, without invigorating the pathomorphological disturbances in the lung.

Changes in the activities of jejunal glucosidases in experimental intestinal tumorigenesis induced by 1,2 dimethylhydrazine in rats fed different diets.

The purpose of the present study was to establish the effect of the carcinogen 1,2 dimethylhydrazine on the activities of the jejunal glucosidases and to assess the possible modifying effect of different diets. Two control groups of Wistar albino rats were used - fed standard pellet diet and fed the same diet + 1,2 dimethylhydrazine treatment. Six experimental groups treated with 1,2 dimethylhydrazine were provided. One of them was fed standard diet, containing 30% of wheaten bran and the other 5 groups received high-lipid diets, containing 30% of different fats. The rats were injected subcutaneously once a week for 12 weeks with 20 mg 1,2 dimethylhydrazine/kg b.m. and left for 12 weeks in order to develop a tumor growth. The activities of 5 glucosidases (lactase, maltase, sucrase, palatinase and cellobiase) were determined in homogenates from jejunal mucosa taken near by the tumors and in homogenates from the tumors themselves. An expressed decrease of the jejunal glucosidase activities near the tumors and in the tumors was established. The animals fed 30% wheaten bran diet did not develop tumorigenesis and showed comparatively slight decrease of the enzyme activities. In general, the high-fat regimens did not exert such a preventive effect.

[Experimental research on the toxicity of pharmapentoxifylline (I)]. / Eksperimentalni prouchvaniia vurkhu toksichnostta na farmapentoksifilin (I suobshtenie).

Results from the study on acute, subacute and chronic toxicity of the therapeutic preparation pharmapentoxiphyline (PP), produced by Pharmachem, are described. The experiments were carried out on 312 male and female white rats. According to the limiting index of LD50 with, Oral dose of (1220 mg/kg of body mass for male rats and 1050 mg/kg for female rats) and intraperitoneal PP dose of PP (230 mg/kg for female rats and 235 mg/kg for female rats) it was included into IV class of slightly toxic compounds. Doses of 100, 300 and 600 mg/kg/oral administration) and 30, 75 and 150 mg/kg (intraperitoneal administration) were used in subacute and chronic experiments. Integral, hematological and biochemical methods and parameters were applied for evaluation of the toxic effect. There was no hemato-, hepato- and nephrotoxicity after oral and intraperitoneal administration of PP in doses of 10 and 30 mg/kg for a period of 3 months. Some recommendations, which should be taken into consideration during continuous treatment with PP, are given on the basis of a complex evaluation of the results from the hematological parameters.

[Experimental research on the toxicity of pharmapentoxifylline (II)]. / Eksperimentalni prouchvaniia vurkhu toksichnostta na farmapentoksifilin (II suobshtenie).

The results from morphological studies on liver, lung, heart, spleen, intestine, brain, skin, testes (ovaries), obtained in the end of the first and third month of animals, treated with pharmapentoxiphyline (PP), are described. The experiments were carried out on 312 white rats (male and female), divided into 2 series: I series--oral usage of the preparation in doses of 100, 300 and 6 mg/kg, II series--intraperitoneal administration in doses of 30, 75 and 150 mg/kg. It was established that PP, administered for a period of 3 months orally in a dose of 100 mg/kg and intraperitoneally in a dose of 30 mg/kg did not induced changes in the structure of all examined organs. Slight dystrophic changes in liver, lung and spleen occurred in the end of the third month under the influence of an oral dose of 300 mg/kg and an intraperitoneal dose of 75 mg/kg. The obtained results are discussed in connection with the pharmacological action of drug-peripheral vasodilatator.

[Effects of preliminary fasting on the development of D-galactosamine-induced acute lesion of the liver in rats]. / Vliianie predvaritel'nogo golodaniia na razvitie ostrogo povrezhdeniiapecheni D-galaktozaminom u krys.

The effect of 48-hour preliminary fasting on the development of acute hepatitis in 24 h after the use of 1,855 mmol D-galactosamine per 1 kg bw has been studied on rats. Both intensification of dystrophic and necrotic processes in the liver and aggravation of ultrastructural changes and disorders have been observed. Concentrations of reduced glutathione in the liver and D-glucaric acid in the urine are not changed under the effect of intoxication.

[Effect of prior starvation on the development of acute thioacetamide-induced liver damage in rats]. / Vliianie predvaritel'nogo golodaniia na razvitie ostrogo pechenochnogo povrezhdeniia tioatsetamidom u krys.

The effect of previous fasting on the liver morphological changes and microsomal cytochrome P-450 and b5 content was studied in thioacetamide-induced (100 mg/kg) rat liver necrosis. Starvation for 48 hours immediately before thioacetamide administration aggravates the dystrophic and necrotic processes, as revealed by histology, electron microscopic investigations and serum aminotransferase activity. The liver microsomal cytochrome P-450 concentration tended to decrease after thioacetamide challenge, with fasting resulting in a more significant loss of cytochrome P-450. Cytochrome b5 content, however, was found to increase in acute liver necrosis induced by thioacetamide.

[Biochemical and histological research on lung tissue in experimental carbon disulfide exposure]. / Biokhimichni i khistologichni izsledvaniia na belodrobnata tukan pri eksperimentalna ekspozitsiia na serovuglerod.

During an experiment on two species of test animals (guinea pigs and white male rats) is studied the effect of carbon sulfide on the biochemical and structural characteristic of the lung. Duration of the experiments 30 days with guinea pigs and 90 days-white male rats. A complex of biochemical and histological methods is applied. Disturbances in the metabolic processes of the lung are established: a) raised activity of the hydrolytic enzymes; b) increased activity of the glycolytic enzymes and c) stronger protein synthesis. The observed metabolic disturbances are based, most probably, on the circulation infringements, occurring in the lung tissue under the effect of carbon sulfide.

[Toxicological study of the long-term effects of the antioxidant dodecyl gallate on albino rats]. / Toksikologicheskoe izuchenie antiokislitelia dodetsilgallata v usloviiakh dlitel'nogo vozdeistviia na belykh krys.

Toxicity of the antioxidant dodecyl gallate was studied in 150-day experiments on male white rats. The antioxidant was administered intragastrically in doses of 250, 50 and 10 mg/kg bw. The general status and behavior of the animals, the survival rate, weight gain, peripheral blood, the amount of urea, total serum protein, soluble proteins of the liver and kidneys, and activity of enzymes (AST, ALT, LDH, SDH, glucose-6-phosphate dehydrogenase, alkaline and acid phosphatase of the serum, liver and kidneys, the weight of the internal organs) were studied over time, followed by morbid anatomy studies. Quantitative determination of serum lipids (total fats, total cholesterol, esterified cholesterol, free cholesterol, triglycerides, free fatty acids, triglycerides plus free fatty acids, and phospholipids) was made on the 150th day after the onset of experiments. When administered in a dose of 250 mg/kg, dodecyl gallate produced death of the animals and an increase in the content of triglycerides plus free fatty acids, a decrease in the weight of the spleen and morphological alterations in the liver, kidneys and spleen. The dose 50 mg/kg was also toxic. It brought about changes in the activity of serum and liver AST, an increase in the content of TF, TG, FFA, TG plus FFA and phospholipids, a reduction in the weight of the spleen and pathological changes in the liver, kidneys and spleen. The dose 10 mg/kg is regarded as liminal.

[Parallel morphological and functional research on chronic enterocolitis patients using the authors' own method for the simultaneous performance of perfusion and biopsy of the small intestine]. / Paralelni morfologichni i funktsionalni izsledvaniia pri bolni s khronichen enterokolit s pomoshtta na sobstven metod za ednovremenno izvurshvane na perfuziia i biopsiia na tunko chervo.

Thirty two patients were studied with chronic enterocolitis and 9 patients without any small intestinal diseases, with normal histomorphological picture of small intestinal mucosa--control group. The method of simultaneous performance of perfusion and biopsy of small intestine was used. Glucose resorption rate in small intestine was studied and histomorphological, electron--microscopic and enzymologic (disaccharidases) studies were carried out on jejunal mucosa. Data about chronic enterocolitis without atrophy were established in 17 patients, in 10--initial partial atrophy, in 5--advanced partial and subtotal atrophy of jejunal mucosa. Reduced glucose resorption rate was established in small intestine in the patients with chronic enterocolitis as compared with that of the control group. Glucose resorption rate correlates with the severity of the histomorphological changes in small intestinal mucosa. Disturbed resorption rate was established via jejuno--perfusion in patients with clinically not manifested syndrome of malresorption and absence of histomorphological changes in small intestinal mucosa, but with established ultrastructural changes in enterocytes.

[Histoautoradiographic analysis of the liver of albino rats treated with low doses of vinyl chloride]. / Khistoavtoradiografichni izsledvaniia na cherniia drob na beli plukhove, tretirani s malki dozi vinilkhlorid.

The authors examined experimental albino rats, treated with low vinyl chloride doses via electronmicroscopic autoradiography by marking with thymidine H3. It was established that no blastic processes developed in liver with the low vinyl chloride doses used. THe authors found a certain inhibition of the plastic functions of hepatocytes, manifested by the diminished marking of thymidine H3 in the nuclei of hepatocytes and Kupffer cells, being of essential importance for an eventual development of the blastic processes in liver.

Origin, structure and function of subcuticular cells of Fasciola hepatica.

In the present paper the ultrastructure of the subcuticulare zone of the tegument of Fasciola hepatica and the distribution of thimidine-H3 for establishing the localization of DNA-synthesis in the tegument was studied. There were two types of subcuticular cells: 1) non-differentiated cells with presence of incorporated labelled thimidine in nuclei presented by DNA non-stable macromolecules, and 2) differentiated or definitive subcuticular cells without aggregates of silver grains. The results showed a high level of DNA replication leading to mitotic activity of the non-differentiated cells and absence of mitotic activity in the definitive cells. There was a morphological similarity between non-differentiated cells and the cells from the medular zone, supposing a relationship in their origin.