Changes in the physicochemical characteristics of rabbit sclera upon scleral reinforcement

Biochemical analysis and differential scanning calorimetry demonstrated that the connective tissue (capsule) formed around a reinforcing scleroplastic implant is similar to intact sclera, its main component being type I collagen organized in perfect fibrils with cross-linking sufficient for normal thermomechanical properties. DSC also revealed a fraction of collagen with heat-labile ‘immature’ cross-links around implants containing a stimulatory plant product Panaxel, which suggested high synthetic activity of fibroblasts.     

Renin-angiotensin and kinin-bradykinin genes polymorphism effects on permanent arterial hypertension in children

New methods are required for more objective estimation of the polymorphic genes contribution in multifactorial diseases. We suggest new approach based on the calculation of relative "score" as a sum of relevant genetic polymorphisms studied. Application of suggested approach is evaluated in analysis of the genes REN (19-83G>A), AGT (M235T), ACE (I/D), AGTR1 (1166A>C), AGTR2 (3123C>A), BKR2 (-58T>C and I/D) in children with arterial hypertension. The method proved that polymorphism of renin-angiotensin and kinin-bradikynin gene systems renders essential influence on formation of stably raised arterial pressure in girls.     

Characteristic Features of Induced Mutagenesis in Hybrid Dysgenesis Systems of Drosophila melanogaster

The mutagenic effect of low-dose gamma-irradiation was studied inDrosophila melanogaster systems of hybrid dysgenesis by estimating polytene chromosome rearrangements, recombination frequency, and viability at the embryonic and postembryonic developmental stages. A dose of gamma-irradiation which had no effect detectable by routine interstrain cross proved to significantly reduce the number of recombinants in the H–E and P–M systems and mortality at postembryonic stages. However, this combined effect was obtained if irradiation followed trasposition, i.e., it depended on the application sequence of the mutagenic factors. The reverse order of the mutagenic treatment led to summation of the effects: as compared to either control, the frequencies of the dominant lethal mutations as well as the larval and pupal mortality in F₂ increased significantly (at the level of 99.9%). This allowed us to estimate the contribution of extremely low-dose gamma-irradiation into the mutagenic effect, which was impossible under routine conditions.     

Characteristic features of induced mutagenesis in hybrid dysgenesis systems of Drosophila melanogaster

The mutagenic effect of low-dose gamma-irradiation was studied in Drosophila melanogaster systems of hybrid dysgenesis by estimating polytene chromosome rearrangements, recombination frequency, and viability at the embryonic and postembryonic developmental stages. A dose of gamma-irradiation which had no effect detectable by routine line crossing proved to significantly reduce the number of recombinants in the H-E and P-M systems and mortality at postembryonic stages. However, this combined effect was obtained if irradiation followed transposition, i.e., it depended on the application sequence of the mutagenic factors. The reverse order of the mutagenic treatment led to summation of the effects: as compared to either control, the frequencies of the dominant allele mutations as well as the larval and pupal mortality in F2 increased significantly (at the level of 99.9%). This allowed us to estimate the contribution of extremely low-dose gamma-irradiation into the mutagenic effect, which was impossible under routine conditions.     

Allele polymorphism of the DNA loci MET, D7S8, D7S23, linked to the cystic fibrosis gene in some populations of the USSR, in high risk families and in cystic fibrosis patients

RELP analysis of DNA loci MET, D7S8 and D7S23 was carried out in Leningrad population and partially in populations of Moscow, Azerbaijan, Ukraine, Buryatia as well as in individuals from high risk families and in cystic fibrosis (CF) patients by means of blot hybridization and polymerase chain reaction. Allelic polymorphism of all loci studied in these three groups was found to be quite similar to that in the North-Western Europe and in whites of the North America. Linkage disequilibrium of the alleles studied with the CF gene was especially pronounced for alleles of the D7S23 locus and gradually decreases from KM-19 through CS-7 to XV-2c DNA probes. The data witness genetic homogeneity of the CF mutation in European populations of the USSR and its similarity to this mutation in Western Europe. The significance of these data for potential diagnosis of CF and for heterozygous carrier detection is discussed.     

The evolutionary changes in the amino acid sequences and properties of the ATP-synthase in chloroplasts, mitochondria and bacteria]

Studies have been made on ATPase from chloroplasts, cyanobacteria and mitochondria of higher plants and animals. No intraspecies and interspecies variability of chloroplast and mitochondrial ATPase was found with respect to pH optimum of the activity, to specificity to cations as substrate components, to sensitivity to stimulating and inhibiting anions and ethanol, to optimal stimulating ethanol concentration. Intergenus variation of these properties of ATPase from chloroplasts, plant mitochondria, and cyanobacteria was revealed. Analysis of homology of the amino acid sequence in ATP-synthase subunits showed that ATP-synthase genes in chloroplast DNA originate from cyanobacterial genome, whereas ATP-synthase genes in plant and animal mitochondria-from genome of Rhodospirillum rubrum or closely related species. It was established that no recombination between the genetic material of chloroplasts and mitochondria took place during evolution.     

Genetic factors of predisposition to endometriosis and response to its treatment]

The relative frequencies of the normal (+) and null (0) alleles of the glutathione-S-transferase M1 (GSTM1) gene, as well as those of the rapid (R) and slow (S) forms of N-acetyl transferase 2 (NAT-2), were studied in the Russian and French populations and in endometriosis (EM) patients. In the total Russian and French populations, the proportions of homozygotes for deletion in gene GstM1 (0/0) were 42.2 and 45.8%, respectively, whereas in Russian and French EM patients, these values were 58.6 and 76.9%, respectively. The differences in these proportions between the total population and subjects with EM were significant at the confidence levels of 0.98 (chi 2 = 5.45; P < 0.02) and 0.90 (chi 2 = 3.01; P < 0.1) for the French and Russian populations, respectively. The frequencies of allele S of the Nat-2 gene were also similar in the Russian and French populations (60 and 63.1%, respectively), with these frequencies being somewhat higher in EM patients (71.2 and 77.7%, respectively). In Russians, the proportion of EM patients who were homozygous for the R form of NAT-2 (R/R) was significantly lower (chi 2 = 5.1). Forty-three of the patients with external genital EM received complex treatment with the use of the interferon inducer Cyclopheron. In 17 patients, a pronounced positive dynamics was observed, and 29 patients exhibited an increased resistance to the immunomodulating therapy. These groups comprised 1 and 25 GstM1 0/0 homozygotes, respectively; the number of patients with the slow NAT-2 form was 13 (7 S/S and 6 S/R genotypes) and 29 (20 S/S and 9 S/R genotypes), respectively. The obtained data indicate that the GstM1 and Nat-2 genes are involved in the EM pathogenesis. Therefore, molecular screening for the GstM1 0 and Nat-2 S alleles would be a good prognostic test when prescribing the postoperative treatment for EM and predicting its effectiveness.     

Structure of the microbial community in soil catena of the right bank of the Oka River

The structure of the microbial community (the fungi-to-bacteria ratio) has been assessed by selective inhibition of the substrate-induced respiration (SIR) using streptomycin sulfate and cycloheximide antibiotics in the gray forest soil of eluvial, transite, transite-accumulative, and accumulative (meadow alluvial) parts of slope landscape on the right bank of the Oka River (near Pushchino, Moscow oblast) which represents an fallow, small-leaved wood, spruce forest, and meadow. The concentrations of bactericide and fungicide were selected experimentally for each landscape parts which provide the greatest SIR inhibition of the soil upon their individual application and in combination. Fungi were established to be predominant in the contribution to the total SIR which was found to be 82–97%. A dependence between the structure of the microbial community and the C/N ratio and pH of the soil was shown.     

The Interaction of miRNA-5p and miRNA-3p with the mRNAs of Orthologous Genes

Molecular Biology - miRNAs regulate the expression of many genes and are involved in the development of diseases. We studied miRNAs that interact partly or fully complementarily with the 5'UTR,...