Introduction of the human recombinant angiogenin at the early stages of postnatal development inhibits the growth of mice

We studied the influence of recombinant DNA containing the cloned angiogenin gene, plasmid DNA without angiogenin gene, and purified recombinant angiogenin injected to Tg8 mice at the age of two days on the body mass of 28- and 40-day old mice. The body mass of mice that were injected with the cloned angiogenin gene or purified angiogenin was less than in the control mice. The body mice of Tg8 mice injected with recombinant DNA containing the cloned angiogenin gene did not increase from day 2 to day 40, while in the mice with purified recombinant angiogenin and control mice it increased by 24 and 57%, respectively. These data suggest that the elevated level of angiogenin at the early developmental stages inhibits the increase of body mass. The effect we described as related, in al likelihood, to the known inhibitory effect of angiogenin on protein synthesis.     

Study of reparative DNA synthesis in lymphocytes of persons occupationally exposed to radiation

The UDS efficiency in lymphocytes of professionals chronically exposed to gamma/neutron radiation, as well as for a control cohort was estimated. A credible reduction of UV-induced UDS (KUV) index as compared to the control was demonstrated. This shows an invalid repair state of blood cells in professionals. As for the control cohort, the decreasing tendency of UDS index with age was found. The correlative analysis of UDS index dependence upon an absorbed dose (based on physical dosimetry data) revealed the trend towards repair index reduction along with a higher total absorbed doze, that is followed by UDS index coming onto a plateau. It was also demonstrated that after a sharp and/or accidental irradiation UDS index reduces as compared to permanent portioned irradiation. It was not observed the influence of smoking upon UDS efficiency in blood lymphocytes neither for control, nor for experimental group. The analysis of vitamin therapy of the both cohorts showed that such therapy raises UDS index of the control (i.e., non-professional) group. Besides, it was found out an additional positive effect of vitamin therapy, i.e. doze leveling in long-term perspective after irradiation. The most expressed KUV/doze correlation was characteristic for professionals, who do not take vitamins and do not smoke. This proves that in blood cells of professionals it is preserved a dependence of repair system invalidity upon the absorbed doze without similar external factors.     

Microbiocenosis of the large intestine in acute complicated pneumonia in children

Fifty-six children of early age with pneumonia developed on the background of frequent respiratory infections were placed under observation. In 91.1% of these cases microecological disturbances in the intestine were detected, 46.6% of the patients having third-degree dysbacteriolysis. In such cases it is more correct to regard the "intestinal" syndrome as the clinical manifestation of disturbances in the biocenosis of the intestine, the state of its microflora. Intestinal dysbacteriosis aggravates the course of acute aggravated pneumonia in children and requires the inclusion of special therapy aimed at normalizing intestinal microflora.     

Thiol-dependent serine proteinase from Streptomyces thermovulgaris

The cultural filtrates of S. thermovulgaris contain a proteinase which is active towards the chromogenic subtilisin substrate, Z-Ala-Ala-Leu-pNa, and azocasein. Pure enzyme preparations were obtained by affinity chromatography on bacitracin-Sepharose with subsequent rechromatography on the same adsorbent. The proteinase was completely inactivated by PMSF and DFP, the specific inhibitors for serine proteinase, by thiol reagents (HgCl2, PCMB) and by the protein inhibitor from S. jantinus. The pH activity optimum for the enzyme is 7.8-8.2, temperature optimum is 55 degrees C. The enzyme is stable at pH 6-9, has a pI of 5.0 and a molecular mass of 32 kDa. When tested against the peptide substrate, the enzyme shows a specificity characteristic for subtilisins. The N-terminal sequence of the enzyme, Tyr-Thr-Pro-Asn-Asp-Pro-Tyr-Phe-Ser-Ser-Arg-Gln-Tyr-Gly, shows a 100% homology with that of terminase, a thiol-dependent serine proteinase. On the basis of the above considerations the enzyme may be related to the subfamily of thiol-dependent serine proteinases.     

3D finite element analyses of insertion of the Nucleus standard straight and the Contour electrode arrays into the human cochlea

Previous experimental studies of insertion of the Nucleus standard straight and the Contour arrays into the scala tympani have reported that the electrode arrays cause damage to various cochlear structures. However, the level of insertion-induced damage by these electrode arrays to cochlear structures (the spiral ligament, the basilar membrane and the osseous spiral lamina) has not been quantified. Although it has been suggested that rotation can overcome this resistance and prevent the basilar membrane from being pierced by the tip of the Nucleus standard straight array, there has not been any attempt to study the relationship between the rotation and the reduction of damage to the basilar membrane. In this study, 3D finite element analyses of insertions of the Nucleus standard straight array and the Contour array into the scala tympani have been undertaken. The perforation of the basilar membrane by the tip of the Nucleus standard straight array at the region of 11-14 mm from the round window appears to be compounded by the geometry of the spiral passage of the scala tympani. Anti-clockwise rotations between 25 degrees and 90 degrees applied at the basal end of the electrode array (for the right cochlea) were shown to significantly reduce the contact stresses exerted by the tip on the basilar membrane which support the practice of applying small rotation partway through insertion of electrode array to minimize damage to the basilar membrane. Although the Contour array (with its stylet intact) is stiffer than the Nucleus standard straight array, a slight withdrawal of the stylet from the Contour array before insertion was found to significantly reduce damage by the electrode array to the spiral ligament and the basilar membrane.     

Increase in the discharge duration under the action of ion-cyclotron plasma heating in the T-11M tokamak

Results are presented from experimental and theoretical studies of the heating of a hydrogen plasma with a lithium admixture at the fundamental ion-cyclotron frequency of hydrogen in the T-11M tokamak. It is found experimentally that the action of RF radiation on a hydrogen plasma containing a small amount (less than 4%) of lithium increases the duration of the discharge current pulse. The effect of the increase in the discharge current pulse under the action of RF radiation is simulated numerically.     

The effect of regulatory sequences of alphaS1-casein gene on the expression of the lacZ-gene in loach Misgurnus fossilis L. transgenic embryos

Transient expression of recombinant plasmids carrying the lacZ gene under the control of either bovine alphaS1-casein gene tissue-specific promoter-enhancer region or highly homologous goat alphaS1-casein gene promoter-enhancer region with supplementary regulatory sequences of the goat gene were studied in Misgurnus fossilis L. loach embryos. It has been shown previously that the expression of the constructs carrying these regulatory elements in transgenic mice occurred primarily in the mammary glands. At early developmental stages, loach embryos and early prelarvae showed nonspecific and mosaic transient expression of lacZ carrying casein regulatory sequences. Transgenic activity was the highest in 1-3-day embryos. At the same time, the efficiency of expression of lacZ gene carrying regulatory sequences of the alphaS1-casein gene of goat was higher than with the promoter-enhancer region of the bovine alphaS1-casein gene. Thus, regulatory sequences of the bovine or goat alphaS1-casein gene appeared capable of providing similar transient expression of reporter gene in the loach embryos. This model can be used for rapid testing of promoter-enhancer activity of transgenes.     

Antibiotic sensitivity of Vibrio cholerae 01 isolated from environmental objects]

The sensitivity of 252 Vibrio cholerae-O1 strains isolated from environmental objects to antibiotics of various groups was assayed by the method of serial dilutions on solid media. The biological characteristics of the isolates are presented. The Vibrio cholerae isolates with serological variation were the most frequent (36.6 per cent), so are the cultures detected by their sensitivity to the specific phages (87.5 per cent). It was found that changes in some biological properties of the strains did not coincide with the changes in the antibiotic sensitivity. The isolates were highly sensitive to tetracycline, chloramphenicol, gentamicin, erythromycin and rifampicin and less sensitive to novobiocin and the other aminoglycosides. The sensitivity to the beta-lactams was the lowest. The resistance determinants were detected in single strains (6.3 per cent), the kanamycin and novobiocin resistance determinants being detected in 15 out of the 16 strains tested. The study showed that the cultures of Vibrio cholerae-O1 isolated from the environmental objects generally preserved their sensitivity to the diverse group antibiotics.