Cellular ultrastructure of the meningococcus when incubated in a continuous culture of human FL-line amnion

Some details of the ultrastructure of several meningococcal strains having had contacts with cells in continuous human amnion cell culture FL for 6 hours to 2 days have been defined with greater precision by means of electron microscopy. The study has shown that the contact of meningococci with the tissue culture is accompanied by the appearance of meningococcal forms with the defective cell wall, similar to L-forms: spheroplast, protoplast, gigantic cells and microcells, as well as budding variants. The meningococcal variants with the defective cell wall, appearing in the cell culture, and the forms occurring (in different proportions) in "ripe" meningococcal populations developing in the culture media for a long time and isolated from a human body have been found to have no essential differences in their fine structure. These data indicate that any external influences (meningococci are highly sensitive to such influences) produce sufficiently rapid changes, similar to L-transformation, in the fine structure of these microorganisms.     

BRCA1 and Estrogen Receptor α Expression Regulation in Breast Cancer Cells

Molecular Biology - BRCA1 (breast cancer 1) protein is involved in the genome stability maintenance participating in homologous recombination-dependent DNA repair. Disruption of BRCA1 functioning...     

Polymorphism of the dopamine transporter gene in populations of the Volga-Ural region

Polymorphism at the dopamine transporter gene (DAT1) in populations of the Volga-Ural region was examined by means of polymerase chain reaction. Statistically significant differences in the dopamine transporter gene allele and genotype frequency distribution were revealed both between the populations belonging to one ethnic group and between the populations from different linguistic families.     

Investigation of monoamine oxidase gene restriction polymorphism in male populations of the Volga-Ural region

Restriction polymorphism at the monoamine oxidase A (MAO A) gene was typed in eight male populations of the Volga-Ural region (Bashkirs, Chuvashes, Tatars, Udmurts, Maris, Mordovians, Komis, and Russians inhabiting the Republic of Bashkortostan). Analysis of the MAO A alleles frequency distribution patterns did not reveal statistically significant differences between the Volga-Ural populations examined. The results obtained suggest genetic homogeneity of the populations described in respect of the polymorphic locus examined.     

Antimicrobial susceptibility and molecular mechanisms of resistance to beta-lactams of gram-negative microorganisms--causative agents of nosocomial infections

Profiles and mechanisms of resistance to beta-lactam antibiotics of isolates of Gram-negative microorganisms, which are causative agents of infections in Intensive Care Unit of hospital surgery department, were studied. Two hundred and ten clinical isolates were studied: Pseudomonas aeruginosa--86 strains (40.9%), Acinetobacter baummanii--45 strains (21.4%), Klebsiella pneumoniae--52 strains (24.8%), Escherichia coli--23 strains (11%), Enterobacter spp.--4 strains (1.9%). Profiles of antibiotic resistance were studied by the method of serial microdilutions; detection of most widespread and clinically significant genes of beta-lactamases of Gram-negative bacteria was performed by polymerase chain reaction. Carbapenems and cefoperazone/sulbactam were the most active antibiotics. Local features of distribution of beta-lactamase coding genes (TEM, SHV, CTX) in K. pneumoniae and E. coli isolates were revealed. Eleven strains of P. aeruginosa resistant to carbapenems and possessing genetic determinants of VIM-group, which codes metallo-beta-lactamases, were isolated. Obtained data allows to assess the parameters of resistance to beta-lactam antibiotics and to reveal the main mechanisms of such resistance in etiologic agents of nosocomial infections, that, in its turn, allows to choose preparations for etiotropic therapy.     

Novel large deletion c.22-1320_633+1224del in the CYB5R3 gene from patients with hereditary methemoglobinemia

Hereditary types I and II methemoglobinemia is a rare autosomal recessive disease due to a deficiency of either soluble or soluble and membrane-bound forms of the enzyme NADH-cytochrome b5 reductase. The molecular genetic bases of both types of the disease consist in changes in the CYB5R3 gene. In this study, the novel and, to date, only large deletion in this gene is described, discovered in two unrelated families with types I and II methemoglobinemia. The common founder haplotype on the chromosomes carrying this mutation was identified. A universal approach for searching for the deletion boundaries was developed, and the c.22-1320_633+1224del deletion breakpoints were determined. In addition, a system for identifying the deletion in heterozygous and homozygous states was designed.     

Polymorphism of the serotonin 2A receptor gene in populations from the Volga-Ural region]

The MspI restriction polymorphism of the serotonin 2A receptor gene (5HT2A) was typed in populations of the Volga-Ural region (Bashkirs, Chuvashes, Tatars, Udmurts, Maris, Mordovians, Komis, and Russians inhabiting the Republic of Bashkortostan). Population-specific patterns of the main polymorphism indices distribution were established. Specific trends in the changes of genotype and allele frequency of the 5HT2A gene depending on the ethnicity of the population were revealed.     

Varied diet and opportunistic foraging in the Ethiopian Bush-crow Zavattariornis stresemanni,an Endangered generalist

The Ethiopian Bush-crow Zavattariornis stresemanni is an endangered, co-operatively breeding southern Ethiopian endemic with a remarkably restricted range (c. 6 000 km²). The species’ range was recently found to be almost perfectly predicted by an envelope of cooler, drier and more seasonal climate than surrounding areas, but the proximate determinants of this range restriction remain unclear. We assessed whether specialisation in diet or foraging may restrict the range of the species by conducting foraging watches to determine prey composition, augmented by observations of opportunistic foraging techniques, and by comparing our results to previously published information on diet. Prey composition comprised a range of arthropods, such as insect larvae (62.7%), beetles (Coleoptera) (15.6%), and grasshoppers and crickets (Orthoptera) (11.8%). Prey was primarily obtained by pecks above ground (74.2%) but also frequently dug up (23.8%). Prey capture was most successful during pecks and we also found chicks were preferentially fed larger prey items over smaller ones by adults. We documented opportunistic behaviours such as nest-raiding and ox-pecking. Diet and foraging are varied and unspecialised, and therefore do not appear to explain the restricted range of the Ethiopian Bush-crow.