Association of C3435T (rs1045642) Polymorphism of the MDR1 Gene with the Increased Risk of Colorectal Cancer in Russian Females from Central Russia

Russian Journal of Genetics - The objective of this study was to examine associations of single nucleotide polymorphisms, rs1045642 within the MDR1 gene and rs1799930 within the NAT2 gene, with the...     

Functional states of antioxidant enzymatic complex of tissues of Mytillus galloprovincialis Lam. under conditions of oxidative stress

Materials are summarized on reaction of enzymatic antioxidant (AO) complex of tissues molluscs of the genus Mytilus on oxidative load of different intensity. It is shown that with increase of the level of oxidative stress there is observed a rise of activities of glutathione reductase (GR) and glutathione peroxidase (GP) as well as increases the turnover rate of glutathione (GSH) in tissues. Then the toxic load is compensated by an elevation of activities of enzymes of low affinity to hydroperoxides, specifically of catalase. In the glutathione system it is possible to identify several relatively steady states: processes of low, moderate, and high intensity. In individual tissues, functioning of the AO system seems to be directed not to detoxication, but to generation of reactive oxygen species (O₂ ^·?, superoxide dismutase), which probably is determined by specifics of their running processes (destruction of damaged byssus threads). The AO complex of molluscs is distinguished by high lability and sensitivity both to physiological states (spanning) and to action of factors of anthropogenic nature (cationic detergents). Responses of the mussel AO complex to natural states and toxic action are comparable between each other, which are necessary to be taken into account at diagnostics of the state of the aquatic environment.     

Solubilization and isolation of dihydropyridine calcium channel blocker receptor from the rabbit skeletal muscle

A microsomal fraction of rabbit skeletal muscle was sed for the isolation of a dihydropyridine (DHP) receptor, a putative potential-dependent calcium channel. The receptor purification was followed by the binding of 3H-labeled riodipine derivative which possesses a high affinity for digitonin-solubilized DHP receptor. The DHP-Sepharose affinity chromatography of an enriched receptor fraction allowed to isolate a receptor, 60-70% homogeneous on the basis of DHP-binding activity. SDS gel electrophoresis showed that the purified receptor is composed of two subunits with molecular masses of 160 and 53 kD. The large subunit changes its electrophoretic mobility after the reduction of disulfide bonds.     

Hemoglobin system of golden mullet (Liza aurata,Risso) at adaptation to conditions of outer hypoxia

Under conditions of experiment, effect of outer hypoxia on the hemoglobin heterogeneous system and respiratory blood characteristics were studied in the golden mullet Lisa aurata R. The control fish group was maintained at oxygen pressure of 158–162 gPa, the experimental group at 54–55 gPa. The exposure was 15 days, the water temperature—15°C. Under conditions of oxygen deficit in the mullet body there is noted development of a complex of compensatory reactions directed to maintenance of the oxygen blood capacity. Initially (the 1st–2nd day), the release of erythrocytes from spleen is noted, which increases the number of red blood cells and the hemoglobin concentration in blood (the emergency adaptation). Subsequently (the 10–15th day), there occur quantitative readjustments at the level of the hemoglobin system, which lead to an increase in the blood affinity to oxygen and to a decrease in its sensitivity to pH (the long-term adaptation). The revealed changes take place on the background of a decrease in volume of circulating erythrocytes, which reflects the character of change of erythrocytic parameters (MCV, MCHC) and seems to be a consequence of partial dehydration of blood plasma.     

Synthesis and biological activity of 7,8-dihydro derivatives of batrachotoxinin interacting with fast sodium channels

7,8-Dihydrobatrachotoxinin (A) (I) was synthesized from 11 alpha-hydroxyprogesterone (III) by a 37-stage procedure. Trimethylpyrrolcarboxylate, benzoate as well as 2-azido-benzoate derivatives of (I) were obtained by mixed anhydride technique, the latter two derivatives being prepared also with tritium atoms in aromatic rings (sp. radioactivity about 28 Cu/mmol). Upon interaction with rat brain synaptosomes the apparent Kd of 7,8-dihydrobatrachotoxinin A 20 alpha-[4-3H]benzoate (Iv) was about 2,5 x 10(-6) M. The (Iv) specific binding was inhibited by aconitine with K0,5 = 1,3 x 10(4) M. Anemonia sulcata toxin II (ATX II) enhanced (Iv) affinity for the receptor up to 7 x 10(-7) M, the maximum binding capacity being 2,5 pmol/mg of protein. Benzocaine and tetracaine competitively displaced specifically bound toxin with K0,5 = 3,1 x 10(-4) M and 5,7 x 10(-7) M, respectively, in the presence of 10(-5) M ATX II. 2-Azido[5-3H]benzoate derivative (Id) was shown to be an effective probe for covalent labeling of the alkaloid toxin receptor of the sodium channel.     

The evaluation of the genotoxic effects of samples of industrial and domestic sewage. II. The mutagenic and recombinant effects of sewage in the soybean (Glycine max. (L.)) test system

The genotoxicity of the industrial and domestic sewage has been studied on the soybean test-system Glycine max (L.). It makes it possible to take into account different types of genetic disturbances according to appearance of various spot types on sprout leaves (somatic mosaicism).     

Statistical methods of comparative genomic analysis based on diffusion processes

Comparative genomics is a powerful tool of genome functional specificity predictions and investigation of evolution specificity. Background of a large field of bioinformatics investigations is a computation of different scores of sequences and comparing them with a threshold. Comparative genomic analysis involves scores comparing for orthological groups of genetic objects. In this paper we represent a statistical approach to comparative genomic analysis, that based on investigation of diffusion in sequence space determined by neutral evolution of sequences. Using this approach we represent several statistics for selection pressure estimation and analyze statistics for several biological problems. We formulate technology of statistics applying to obtain new biological information. This approach is represented as Java-class library.     

Structural changes of erythrocyte membrane revealed by 3D confocal optical profilometer

We examined hematological changes influenced by the experimental hypervitaminosis A. The 3D confocal optical profilometer was applied for assessment of the erythrocytes' membrane structural changes influenced by an overdose of vitamin A. The blood smears were evaluated in terms of alterations of geometrical and optical parameters of erythrocytes for two groups of animals: oil base and retinol palmitate (n = 9 animals for each group). The results demonstrate that an overdose of retinol palmitate causes changes in the torus curvature and pallor of discocytes, their surface area and volume. The observed structural malformations of the shape of red blood cells become visible at the earlier preclinical stage of changes in animal state and behavior. With this in mind, the results of the study open a new area of research in the certain dysfunction diagnosis of red blood cells and have a great potential in the further development of new curative protocols.     

A receptor of dihydropyridine blockaders of Ca2+ influx in human embryonic fibroblasts

The plasma membrane of human embryonic fibroblasts was shown to contain receptor binding sites for 1,4-dihydropyridine (DHP) Ca2+ entry blockers. In a subconfluent culture grown in serum medium the content of the DHP receptor amounted to 1.2 +/- 0.3 pmol per 10(6) cells. With progression to confluency this value decreased up to 0.28 +/- 0.08 pmol per 10(6) cells. The DHP binding capacity was shown to be affected by the presence of growth factors in culture medium. In a subconfluent culture of serum-deprived cells the content of DHP binding sites increased 1.9 fold, the steady-state level being achieved within 3 days in culture. The serum gradually reversed this process, and the DHP receptor density approached the initial level within 3 days.