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Sociological poll of inhabitants of Chelyabinsk concerning a balanced diet was conducted. Every second chelyabinets needs change of the food, but thus has for this purpose no sufficient money resources. Deficiency in a food of animal protein, the majority of vitamins, macro- and microelements and saturation of a diet by carbohydrates and fats was shown. It was established that the products of mass consumption: bakery, dairy, meat,fat-and-oil products and sweets can be considered as potential products for enrichment, oriented for low-and middle-income countries primarily.

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The article deals with 6 -year experience of the Centre of Oncoangiosurgery of the Chelyabinsk Regional Oncological Dispensary in treatment of patients with concomitant malignant neoplasms and atherosclerotic lesions to the aorta and arteries. The authors analyze therapeutic outcomes in a total of 158 patients. Of these, 81 patients were subjected to surgical correction of the blood flow. The presence of a clinically significant atherosclerotic lesion of the aorta and peripheral arteries in a patient should not be interpreted as an absolute or relative contraindication to contraindication combined treatment of the tumour concerned. In the majority of cases, atherosclerotic occlusion of femoral and tibial arteries was treated conservatively, using <>. In manifestation of an atherosclerotic lesion to the carotid arteries, aorta and iliac arteries, surgical correction of the blood flow was used more often. Usually, vascular reconstruction was carried out first. Simultaneous interventions were performed in 16 patients; three patients died. The technique of operations on the aorta and arteries was traditional, while for revascularization in peripheral lesions to the arteries of the limbs more frequently compromising methods were used (sympathectomy, profundoplasty, local endarterectomy) on the background of prostaglandin E1 infusions.

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The results are presented of 5-year experience with therapy of concurrent neoplasia and atherosclerotic lesions of the aorta and peripheral arteries gained at the Center for Oncosurgery, Regional Oncological Dispensary, Chelyabinsk. The analysis was concerned with the treatment received by 118 patients, irrespective of tumor stage or localization: surgical correction of blood flow was carried out in 60. Clinically significant atherosclerotic lesions of the aorta and peripheral arteries in a cancer patient should not be regarded as absolute or relative contraindication for combined treatment. Atherosclerotic occlusion of the femoral or shin arteries was managed conservatively in most cases (p<0.05). In cases of similar lesions of the carotid arteries and aortal aneurysm, surgical correction of blood flow was mostly used.

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The paper summarizes the results of examination of 100 patients with malignant tumors of the lung. The results of X-ray study, linear tomography, and computed tomography (CT) used in the examination of patients with lung cancer were compared by using as an indicator the following parameters: to make diagnosis of lung cancer, to reveal mediastinal intergrowths, to detect enlarged lymph nodes, pulmonary metastases, and pleural lesions, to obtain information on tumor spread into the chest, to reveal growths into the vascular walls. To evaluate the efficiency of the techniques in solving the above diagnostic tasks, a statistical analysis including the estimation of their accuracy, specificity, and sensitivity was made. Recommendations for examination of patients with lung cancer were drawn up for therapeutic institutions of different types.

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Within the period from 1989 to 1993, the impact of heavy metals and acid oxides on lakes, more than 100 km distant from the nearest source of pollution (enterprises of the copper-nickel industry), has been investigated. On the basis of complex investigations (chemical composition of snowpack and lake sediments, state of fish organisms and populations), it was discovered that there is intensive precipitation of heavy metals and acid oxides within the catchment of the lake Kochejavr. The catchment is characterized by a natural buffer capacity to neutralize acid precipitation. Active accumulation of heavy metals is observed in lake sediments. Metal accumulation causes subtoxic effects on the lake fish. The levels of precipitation of nickel and copper of 0.9 mg/m2 per year over long periods was found to be dangerous for biological systems of freshwater catchments.

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The contents of Cd, Cu, Cr, Hg, Ni and Zn in muscle, liver and gills were studied in whitefish, perch, pike, brown trout, burbot and vendace from three lake localities in a watercourse in the border region between Norway and Russia, in the vicinity of mining activity and several metallurgic smelters. The contents of Cd and Ni in fish tissue increased with increasing proximity to the smelters, whereas the other elements showed similar concentrations at the three localities. The recorded heavy metal concentrations appeared to be within the ranges reported for fish from other metal-contaminated lakes, and higher than comparable observations from unpolluted systems. The heavy metal concentrations were usually lowest in muscle and highest in the liver or the gills. Significant differences in metal concentration levels were found between different fish species, but Hg was the only metal where these species differences were possibly related to biomagnification. For the other elements, the concentrations generally appeared to be inversely related to the trophic level of the fish species.

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The modern status of the biological role of peptide antibiotics in vital activity of bacilli is discussed. The published data and the original findings of the author and his coworkers are analyzed from the viewpoint of two hypothesis: regulator and protective. It is shown that at present there is no solid basis for considering antibiotics as positive regulators of sporulation in organisms producing them. Synthesis of antibiotics is thought to be a manifestation of a certain stage in ontogenetic development of bacilli and is associated with production of extracellular enzymes. The enzymes are conjectured to perform in nature hydrolysis of exogenic substrates and thus create nutrient medium for vegetative cell division of antibiotic-producing organisms. The author suggests that the main biological function of peptide antibiotics produced by bacilli is protection of their environment from other microorganisms.

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Sporulation and synthesis of bacitracin, a peptide antibiotic and serine exoproteases and endoproteases were studied in 6 strains of Bacillus licheniformis at various periods of cultivation in sporulation media. Thermostable spores in all the strains were shown to form in the absence of both the exogenic and endogenic antibiotic and proteases. It was suggested that bacitracin and the serine proteases were not specific regulators of sporogenesis in B. licheniformis and their biological function under the natural conditions included, respectively, the antibiotic action and hydrolysis of proteins and peptides of the environment and cells.

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The vegetative cells of B. licheniformis, producing bacitracin, a feed grade peptide antibiotic were exposed to nitroso guanidine and six mutants with lowered activity of serine exoprotease in the culture fluid were isolated. It was found that synthesis of bacitracin and sporulation of the mutants were impaired. The cause of the impairment is not known. The results are discussed from two viewpoints: serine exoprotease is responsible for positive regulation of bacitracin biosynthesis and sporulation at the account of forming an amino acid pool in the medium, simultaneous changing of the three features in the mutants may be due either to a single pleiotropic mutation or to multiple mutations independently induced by nitroso guanidine.

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The aim of the present paper was to study the specific character of interaction of peptide antibiotic bacitracin with DNA and to estimate the interaction constant. The influence of bacitracin on bacteriophage DNA restriction by HindIII and SmaI endonucleases was studied. The possibility of arranging the polynucleotide template by small ligands was shown.

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Sporulation in different strains of Bacillus licheniformis, 10716 and 1001 in connection with changes in synthesis of bacitracin was studied. It was shown that the sporulation efficiency did not depend on the synthesis of the antibiotic: in some strains with low potency for the antibiotic production, the sporulation level was lowered, while in the others, it was not lowered. Moreover, normal sporulation was also observed, when the synthesis of bacitracin was inhibited. Therefore, it is suggested that there is no correlation between the sporulation and antibiotic production.

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The literature data and the results of the experiments performed by the authors on possible participation of peptide antibiotics in regulation of cell differentiation in bacteria were analysed. It was shown that the available experimental data were in conformity with the regulatory hypothesis. According to this hypothesis the biological role of peptide antibiotics lies in participation in the control of sporulation and germination of the spores rather than in protection upon competition of different microorganisms in nature.

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Ribosomal mutants of Bacillus subtilis IG2 and IG7 resistant to 100 mkg/ml of streptomycin have been isolated. The strA80 and strA88 mutations reduce the level of sporulation as well as antibiotic and proteolytic activity of bacteria. RNA polymerase mutations rfm20 and rfm146 transferred by transformation into ribosomal mutants suppress strA80 and strA88 mutations. As a result, sporulation was restored. Both mutations were cotransformed with cysA gene and mapped within the cluster of ribosomal and RNA polymerase genes. It is proposed that the ribosomal strA80 and strA88 mutations influence transcription of gene (s) which regulate initiation of sporulation and that the RNA polymerase rfm20 and rfm146 mutations can restore sporulation. The results suggest that ribosomes are most likely to be not able to play a specific role in sporulation and secondary metabolism of Bac. subtilis.

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There are about 20 copies of pPL7065 plasmid in cells of Bacillus pumilus ATCC7065 with molecular weight of 4.7 X 10(6) daltons. A spontaneous purine dependent mutant LK1 was isolated which contained no autonomous plasmid. However, the presence of the plasmid in LK1 cells was proved by DNA - DNA hybridization. To accomplish this, hybrid plasmid p1G1 was constructed by cloning pPL7065 on a vector pBR322 and multiplying it in Escherichia coli C600. The plasmid then was hybridized with chromosomal DNA of Bac. pumilus LK1. A pur+ revertant has been obtained from LK1 containing autonomous plasmid pPL7065, similar to the parental strain ATCC7065. These results are indicative of pPL7065 integrated into the chromosome of LK1. Bacteria having the autonomous plasmid are oligosporogeneous and produce specific antibiotics. Integration of the plasmid into bacteria causes pur phenotype, normal sporulation and a change in antibiotic synthesis and resistance. LK3 strain which lost pPL7065, sporulates normally and produces the antibiotic that inhibits growth of Bac. pumilus ATCC7065.

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The synthesis of the antibiotic bacitracin in lysogenic and nonlysogenic strains of Bacillus licheniformis 1001 and ATCC10716 has been studied. The antibiotic activity was shown to be about 20% less in lysogens, as compared to nonlysogens. However, the level of bacitracin production was completely restored when temperate bacteriophages BL20 and LP52 were reintroduced into the nonlysogenic strains by virtue of genetic transformation with DNA from lysogenic strains or by transduction with LP52. This may indicate that both phages take part in control of the synthesis of bacitracin. For the time being, the mechanism of regulation is not known. It is likely to be either direct (provided that prophage DNA contains "bacitracin" genes), or indirect.

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The aim of the present paper was to study the action of one of the peptide antibiotics, bacitracin, as the regulator of gene activity at the transcription level. Therefore the commercial bacitracin has been fractionated into two main parts by paper chromotography. These two fractions have been identified as bacitracin A (biologically active) and bacitracin F (biologically inactive). The binding of both fractions to DNA has been studied. It has been shown that bacitracin A stabilizes DNA to a lesser degree than bacitracin F does. DNA-bacitracin complexes are formed in the major groove of the DNA helix by hydrogen bonds. The analysis of the the obtained experimental data allows us to suppose that bacitracin binding to DNA has a very specific character and that this antibiotic may act as the regulator of gene activity.

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The role of plasmid pPL 7065 in the control of the antibiotic production and sensitivity in Bac. pumilus was studied with the use a plasmid-free strain and strains containing the plasmid in the cells in a free or chromosome-integrated state. It was found that all the strains had antibiotic activity only with respect to a limited number of gram-positive bacteria. Still, the antibiotics produced by them differed in the antibacterial spectrum. The antibiotic produced by the plasmid-free strain had a broader spectrum. It was shown that the bacteria with the plasmid in th free state were sensitive to the antibiotics produced by the plasmid-free strain for the strain or the strain with the chromosome-integrated plasmid. It was suggested that plasmid pPL 7065 played the role of a modifier of the antibiotic activity and sensitivity in Bac. pumilus and carried no genetic information for the control of the antibiotic synthesis. Their formation is determined by the chromosome genes.

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