Changes in the topological state of DNA duringEscherichia coli adaptation to oxidative stress under glucose starvation and after the transition to growth

Changes in the topological state of DNA occur in a starvingEscherichia coli culture under oxidative stress caused by the addition of hydrogen peroxide. The addition of a carbon and energy source to this culture results in a second stress reaction. This supports previous data indicating that different mechanisms are responsible for the cell defense against oxidative stress in exponential and starvingE. coli cultures. Polyamine synthesis is involved in the cell adaptation to the stress. Putrescine binding to DNA and its dissociation seem to modulate the DNA topological state, which regulates the expression of the adaptive genes. An increase in the activity of the polyamine-synthesizing system in response to oxidative stress leads to a putrescine flux across the cytoplasmic membrane, due to which the antioxidant activity of putrescine protects the membrane phospholipids and contributes to the restoration of the cell energy-generating function     

Character of arterial pressure changes under combined action of pressor and depressor agents

It is shown in acute experiments in cats that byphasic arterial pressure changes occurred due to action of two heterodirectional and equivalent humoral stimuli. Magnitudes of both initial depressor and following pressor phases were authentically less than the ones due to separate action of those stimuli. It is noticed that the character of sum reaction depends neither on action mechanisms of vasoactive agents in the blood circulation system nor differences in the latent period of the effect of those drugs, but connected with intensiveness of stimuli. Predominance of depressor phase magnitude was shown to observe due to a rise of stimuli intensiveness down to complete disappearance of pressor reaction.     

Hantaviruses in small wild living mammals in Czechoslovakia. Results of a 1983-1989 study

During a 7- year period were hunted small wild living mammals and examined by ELISA and RIA techniques for the presence of hantavirus antigen and/or antibodies by MFA. In total 3,050 animals of 16 species caught in 9 out of 10 regions of Czechoslovakia, were examined. The proportion of positive animals was 4.4%. To the positive ones with the serotype 2 (Western type) belonged the following: M. arvalis, C. glareolus, P. subterraneus, A. sylvaticus, A. flavicollis. To the Eastern serotype: A. agrarius in eastern Slovakia, A. flavicollis in North of Bohemia and A. sylvaticus in South of Moravia. The repeatedly examined localities were found to be either repeatedly positive or repeatedly negative. The antigen titres in the lungs of M. arvalis were constant irrespective of sex and season of capture. They were, however, much higher in young animals, whereas the proportion of positivities was higher in adults ones. The titres of antigen in the lungs of C. glareolus never exceeded those of M. arvalis.     

Pulmonary circulation in experimental pulmonary edema during diverse artificial respiration regimes

In acute experiments on cats with closed chest by ultrasonic method the authors studied the blood flow in low-lobar pulmonary artery and the vein, the blood pressure in pulmonary artery, lung vessels resistance in experimental pulmonary edema caused by intravenous infusion of mixture fatty acids at artificial ventilation of increased frequencies or volumes, at was shown, that artificial ventilation of increased frequencies in pulmonary edema reduces the pressure increase in pulmonary artery, lung vessels resistance and increases the blood flow in pulmonary artery and vein. Artificial ventilation of increased volumes produces more intense pressure increase in pulmonary artery and lung vessels resistance than in initial ventilation but the blood flow was slightly changed. The authors assume that artificial ventilation of increased frequencies or volumes in pulmonary edema due to pulmonary circulation change reduces the pulmonary edema intensity at the beginning.     

The capacitive function of the spleen during electrical stimulation of the structures of the ventral section of the medulla oblongata

In acute experiments on cats under perfusion with constant blood expenditure of hemodynamically isolated spleen the authors studied the reactions of its vessels in the electrical stimulation of ventral brainstem. It was shown that the stimulation of the rostral zone of these structures increased vein outflow from the spleen. It was shown the deterioration of the parametres which characterize a capacitance function of the spleen by stimulation of a causal depressor zone of the brainstem by means of the current of threshold size and its increase by irritation of the brain structures with a 2 threshold current size. There have been made a supposition has been made about the participation of the pointed structures of the brain in the regulation of a vasomotion tonus of the spleen vessels.     

Specific features of feeding of the Amur tiger Panthera tigris altaica (Carnivora, Felidae) in a densely populated locality (with reference to Bol’shekhekhtsirskii Reserve and its environs)

Specific features of feeding of the Amur tiger (Panthera tigris altaica) in the Bol??shekhekhtsirskii Reserve located in a densely populated locality (15 km to the north of the city of Khabarovsk) have been investigated. For a long time (1992?C2000) the diet of tigers consisted 100% of wild animals, although the accessibility of domestic animals, dogs, in particular, was high. From 2000 to 2007, in their feeding, the proportion of dogs increased (up to 47%), and the proportion of wild animals decreased (50.8%). Tigers attacking dogs were physically weakened (broken fangs, wounds, inflicted by humans, diseases). It was shown that even in a densely populated locality, the tiger??s diet includes domestic animals only at exposure to different negative factors.     

Outbreaks of pseudotuberculosis and intestinal yersiniosis among Soviet specialists and members of their families in the Mongolian People's Republic

In summer and winter of 1986 two outbreaks of alimentary enteric diseases occurred among Soviet specialists and members of their families in Ulan Bator. These diseases were identified as Yersinia infections registered in Mongolia for the first time. In July 114 children in a kindergarten fell ill after being fed with salad prepared from vegetables and spring onions supplied from a nearby state farm. 20 Y. pseudotuberculosis cultures, serovar 1, were isolated, and in 25 persons antibodies to the isolated microorganisms were detected; altogether 32% of cases were confirmed by laboratory methods. During the December outbreak 187 persons were affected, among them 90% of children, through the consumption of imported oranges and tangerines, simultaneous infection with Y. enterocolitica, serovars 05.27 and 09, and hepatitis A virus being observed. The fact of associated infection was registered after the simultaneous detection of the markers of viral hepatitis A and Yersinia infection in 61 patients. In the kindergarten the disease produced a typical clinical picture of Far Eastern scarlatiniform fever, and in winter the abdominal forms of the disease prevailed. In cases of combined Yersinia and viral infection a specific variant of acute hepatitis developed; as regards this variant, the authors present heretofore unknown information on its epidemiology, clinical features and outcome.     

Pollution-related changes in oxidative stress and antioxidant defense profile in the blood of white stork Ciconia ciconia chicks from different regions of Poland

Changes in the lipid peroxidation and oxidatively modified protein levels as well as the antioxidant defense system in the blood of white stork (Ciconia ciconia) chicks were analyzed during their development in nests in polluted and control environments. The control, relatively pure, environment was the village of K?opot, with no industrial plants within a radius of 150 km. Blood samples were also collected in two polluted areas, including (1) the suburban village of Czarnowo, located 20 km from the city of Zielona Góra (southwestern Poland) and (2) an area near the town of G?ogów, where a large copper smelter is situated. The effects of various ecological threats from different environments tended to initiate oxidative stress and decrease total antioxidant capacity. The initiation of lipid peroxidation and increases in the levels of carbonyl derivatives of oxidative amino acids were observed in the plasma of chicks from polluted areas. Plasma catalase and the selenium-dependent glutathione peroxidase activities of erythrocytes were significantly higher in chicks from polluted areas than in those from control areas. Oxidative stress and components of the antioxidant defense system, especially glutathione peroxidase activity, can be used as indicators of oxidative stress, which was found to be greater in the polluted areas (near the G?ogów copper smelter). Research into oxidative stress biomarkers can aid assessments of the conditions of birds, and points to a positive association with miscellaneous environmental loads.     

Synthesis of substituted diphenyl sulfones and their structure–activity relationship with the antagonism of 5-НТ6 receptors

Substituted diphenyl sulfones (10a–n) were synthesised, and the structures were confirmed by NMR, LC–MS and X-ray crystallography. Their antagonistic activities towards 5-HT₆ receptor were assessed in a cell-based functional assay. Diphenyl sulfone 10a, in spite of being the smallest and simplest known sulfonyl-containing 5-HT₆R antagonist, showed a strong potency (K_i = 1.6 μM). Its derivative with a methylamine substituent, 10g (N-methyl-2-(phenylsulfonyl)aniline), was ～66-times as active as diphenyl sulfone (K_i = 24.3 nM). Addition of a piperazinyl moiety in the para-position relative to the sulfonyl group in compound 10m (N-methyl-2-(phenylsulfonyl)-5-piperazin-1-ylaniline) led to a further 150-fold increase in potency (K_i = 0.16 nM) to block the serotonin-induced response of HEK-293 cells that were stably transfected with the human recombinant 5-HT₆ receptor.     

Relationship of single-nucleotide polymorphism rs11562975 in thermo-sensitive ion channel TRPM8 gene with human sensitivity to cold and menthol

The examination of people belonging to the Russian ethnic group revealed that 20.3% of subjects had heterozygous genotype, containing the C-allele in single nucleotide polymorphism rs11562975, located in exon 7 of the gene encoding the temperature-sensitive ion channel TRPM8. Functional differences, associated with sensitivity to cold and menthol were identified between subjects with different genotypes of the polymorphism rs11562975 (GG and GC). Subjects with heterozygous genotype GC were characterized by increased sensitivity to cold and reduced sensitivity to menthol, agonist of the ion channel TRPM8, compared with subjects with homozygous genotype GG.