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Heat capacity, thermal dilatation, sensitivity to pressure and permittivity of NH4HSO4embedded into glass matrices with a pore size of 320 nm and 46 nm were studied. Large difference in the thermal expansion of both glass and ferroelectric leads to a “clamped” state of NH4HSO4in nanocomposites and to the phase transition temperatures change. The restricted geometry does not effect on the order of successive transformations in NH4HSO4but is accompanied by a significant reduction in entropy of phase transitions. The behavior of DTA-signal and permittivity show the expansion of the temperature range of the ferroelectric phase under hydrostatic pressure. [ABSTRACT FROM PUBLISHER]

Using a program we developed allowing us to take into account zero-field splitting, spin-orbit, and exchange interactions in polynuclear complexes, we have interpreted the temperature dependences of the magnetic susceptibility for the complexes FeCoO(CFCO)(HO)·HO ( 1) and [Co(HO)][CuL(HO)]·3HO ( 2, HL = 1,9-dicyano- 1,9-bis(hydroximino)-3,7-diazanonane-2,8-dione). We have analyzed the differences between the values of the simulation parameters determined within different theoretical models. [ABSTRACT FROM AUTHOR]

Modern views of the strategy for the treatment of the main gastroenterological diseases during pregnancy are considered. Peculiarities of the clinical course of digestive tract pathologies are discussed with reference to the influence of exacerbation of their chronic forms on fetus development. The most common gastroenterological pathologies include gastroesophageal reflux disease, gastric and duodenal disorders, acute and chronic pancreatitis, acalculous and calculous cholecystitis, hepatitis of autoimmune and other etiology, liver cirrhosis, intestinal inflammation. Possibilities of pharmacotherapy and its specific features in pregnant women are discussed including cases of exacerbation of chronic conditions.

The development of the reproductive organs and the gametogenesis of animals are complex and multistage processes that require the precise and effective regulation. In this review, we summarized the recent findings about essential functions of miRNAs in the regulation of gene expression during the differentiation of germ cells in spermatogenesis and oogenesis. Most probably, the main functions of the conservative and highly-expressed miRNAs in the reproductive organs of mammalian are the control of differentiation and proliferation of cells. Also we discussed the possible involvement of the germline-expressed miRNAs in the formation of the reproductive barriers and speciation.

Complexes of Piwi proteins and Piwi-interacting RNAs (piRNAs) carry out the repression of transposable elements in animal gonads. The Piwi protein clade is represented in D. melanogaster by three members: Piwi, Aub and Ago3. Piwi protein functions in the nuclei of somatic and germinal ovarian cells, whereas Aub and Ago3 are cytoplasmic proteins of germinal cells. Aub and Ago3 interact with each other in the perinuclear nuage organelle to perform piRNA amplification via the ping-pong mechanism. Previously, derepression of several transposable elements as a result of mutations in the piRNA silencing system was shown. Here we quantify the increase in expression level of an enlarged number of retrotransposons due to the mutations in the piwi gene, nuage components coding aub, mael and spn-E genes and the RNA helicase armi gene mutation that impairs Piwi nuclear localization, but not the ping-pong cycle. We reveal that piwi, armi, aub, spn-E and mael genes participate together in the repression of several transposons (HMS-Beagle, Gate and HeT-A), whereas silencing of land G elements requires the same genes except piwi. We suggest that Armi has other functions besides the localizing of Piwi protein in the nuclei. Our data suggest also a role of cytoplasmic Aub, Spn-E and Mael nuage proteins in Piwi-mediated repression of Gate and HMS-Beagle transposons in the germline nuclei. As a whole, our results corroborate the idea that genome stabilization in the germline is realized by different silencing strategies specific for different transposable elements. At the same time, our data suggest the existence of yet unknown mechanisms of interplay between nuclear and cytoplasmic components of the piRNA machinery in the germline.

The authors propose the definition of chronic constipations (CC) and present data on their incidence and classification along with a concise review of physiology and motor-evacuation function of the colon and defecation act. Pathogenesis and clinical symptoms of different forms of functional and organic CC are discussed. Instrumental and laboratory methods for the examination of patients with CC are described including special techniques for the diagnosis of abnormalities in the anorectal region. Special attention is given to modern approaches to individual therapy including correction of life style and dietary habits as well as the choice of adequate drug therapy. The proposed classification of purgative drugs takes into account indications for their use, contraindications, and adverse effects. Selected methods of physiotherapeutic and surgical treatment of CC are described.

A convenient and efficient method for three-dimensional immobilizing oligonucleotides on glass was developed using oligonucleotide derivatives bearing a polyamine linker (PA-oligo conjugates). Polyamine (polylysine, poly(lysine, phenylalanine), polyethyleneimine) residues stipulate durable fixation of such conjugates to the glass surface with a high yield (90-95%). A DNA fragment (414-mer) is hybridized specifically to an immobilized oligonucleotide.

To test the conception about a pathogenetic role of correlation between gastric comtamination with Helicobacter pylori (Hp) and immune system disorders in duodenal ulcer (DU), immune status and its response to current pharmacotherapy were studied in 84 patients in an acute recurrence phase. The patients were divided into 4 representative groups to receive monotherapy with omeprasol (group 1), combination denol + amoxicillin + tinidasol (group 2), quadrotherapy with drugs of group 1 and 2 (group 3), the above quadrotherapy plus immunomodulating drugs (imunofan + tactivin + oligovit) (group 4). In recurrent DU all the components of the immune system are affected especially cellular immunity. The response to the treatment was highest in group 1 and 4 (90% healing for 3 weeks), the worst in group 2 (68%). The complex of antibacterial drugs produces a moderate immunosuppressive action. The addition of immunomodulating drugs to the quadrotherapy promotes correction of secondary immunodeficiency and secondary Hp resistance to antibacterial drugs. This leads to a rise in eradication effect from 33-55 to 84% and a decrease in the number of early recurrences (during the first 6-12 months) from 42.1-33.6 to 12.5%.

Glycoprotein with biochemical characteristics that allow us to classify it as a glycoprotein of mucin-type was isolated from cultured embryonic cells of Drosophila melanogaster. This is the first finding of mucin-type glycoprotein in insects. Using high-affinity monoclonal antibodies against a carbohydrate epitope, we demonstrated that the accumulation of this glycoprotein in the culture fluid of Drosophila cell line and cultured cells of other insects was inhibited by secretion inhibitors. 20-hydroxyecdysone, a hormone responsible for molting and metamorphosis in insects, inhibits the accumulation of this glycoprotein in the culture fluid, as well as in cells of Drosophila Dm cell line. In another cell line (Schneider-2), where there was practically no secretion of this glycoprotein, the hormone induced its increased accumulation in the cells. Mucin glycoproteins recognized by monoclonal antibodies have been found in embryos, imaginal disc, fat body, testicles, and ovaries, but not in salivary glands or muscles of Drosophila.

A secreted glycoprotein (GP) with apparent molecular mass of 90 kDa produced by cultured embryonic cells of Drosophila melanogaster was isolated and partially characterized. GP is enriched by Ser + Thr and Pro residues that constitute up to 30% of the total number of amino acids. An abundant carbohydrate moiety (40% of molecular mass) is mainly represented by vertebrate mucin-type O-linked disaccharide units Gal(beta 1-3)-GalNAc, occupying about a half of the total number of Ser+Thr residues and rendering the GP molecule high resistance to protease action. A few of N-glycans are also present in GP. These characteristics allow to consider the Drosophila GP (termed 'mucin-D') as a first representative of invertebrate mucin-type glycoproteins.

The glycoprotein from cultured cells of D. melanogaster, also detected in various insect tissues as a component of the extracellular matrix, was characterized as a mucin-type glycoprotein not yet described in invertebrates. This glycoprotein with an apparent molecular mass of approximately 90 kDa contains about 40% of carbohydrates, largely represented mainly by GalNAc and Gal; its polypeptide moiety is enriched with Thr, Ser, Pro and Gly. An analysis of oligosaccharides liberated by treatment of the glycoprotein with alkaline NaBH4 or O-glycanase (endo-alpha-N-acetylgalactosaminidase) revealed Gal(beta 1-3)GalNAc as the major type of the sugar chains. About half of the Thr + Ser residues in the glycoprotein were estimated as O-glycosidically linked with the disaccharide units.