Division-induced DNA double strand breaks in the chromosome terminus region of Escherichia coli lacking RecBCD DNA repair enzyme.

Marker frequency analysis of the Escherichia coli recB mutant chromosome has revealed a deficit of DNA in a specific zone of the terminus, centred on the dif/TerC region. Using fluorescence microscopy of a marked chromosomal site, we show that the dif region is lost after replication completion, at the time of cell division, in one daughter cell only, and that the phenomenon is transmitted to progeny. Analysis by marker frequency and microscopy shows that the position of DNA loss is not defined by the replication fork merging point since it still occurs in the dif/TerC region when the replication fork trap is displaced in strains harbouring ectopic Ter sites.

[FEATURES OF CLINICAL COURSE OF INFECTIOUS MONONUCLEOSIS IN CHILDREN DEPENDENT ON ETIOLOGY].

The article highlights the clinical features of infectious mononucleosis in children (based on the analysis of the data for children of different ages treated in Odessa clinical hospital of infectious diseases in connection with infectious mononucleosis) based on etiological factors.

[Assemblages of bloodsucking mosquito larvae (Diptera: Culicidae) in water bodies of the northern Kulunda steppe].

The population structure of bloodsucking mosquito larvae in temporary and constant water bodies of the northern Kulunda steppe was investigated. The seasonal dynamics of the population density, the number of species in different types of reservoirs, and average density of each species are given. The productivity of water reservoirs in relation to mosquitoes of the family Culicidae is analyzed.

[Species composition of mosquitoes (Diptera, Culicidae) and possibility of the West Nile virus natural foci formation in the South of Western Siberia].

In 2004 June-July collections of mosquito adults and small mammals were carried out in two areas of Novosibirsk Region (forest-steppe and steppe zones), where the West Nile virus (WNV) was for the first time recorded in birds with different migration status in 2002-2004. Seventeen species of mosquitoes were found; significant changes in their species composition and abundance, as compared with latest faunistic studies made in the sixties-seventies of the last century, are revealed. WNV markers (antigen, RNA) are found in small mammals; highly sensitive to the WNV replication mosquito species are also found.

[On the fauna and ecology of mosquitoes (Diptera: Culicidae) in forest-steppe and steppe regions of Western Siberia].

Fauna and ecology of the mosquitoes from the southern forest-steppe (Chany Lake) and the northern steppe (Karasuksky lakes) have been investigated during 2004-2006. Species composition, dominant species, biotopical and seasonal distribution are examined. Detailed data on the biotopical and seasonal distribution, sex ratio and terms of development for the dominant species Coquillettidia richiardii (Ficalbi, 1889) are reported.

[Features of gastroesophageal reflux disease in young people].

The article contains ethiopathogenic, clinical and diagnostic criteria of gastroesophageal reflux disease (GERD) in young people. GERD verification was based upon the results of the examination of 137 men aged 18 to 23 years. These results included clinical findings as well as the data from the following tests: intraesophageal and intragastric pH-metry with evaluation of parietal cell response to atropine, and endoscopic and morphological examination of the upper division of the gastrointestinal tract including detection of Helicobacter pylori (HP) expansion, evaluation of inflammatory and regenerative processes in the mucosa of the lower third of the esophagus and the antral part of the stomach.

[Thermostability of alkaline phosphatase of Meithermus ruber bacteria: cloning of the gene, expression in Escherichia coli cells and biochemical characterization of the recombinant protein].

The Meiothermus ruber alkaline phosphatase gene was cloned, expressed in Escherichia coli cells, and sequenced. The enzyme precursor, including the putative signal peptide, was shown to consist of 503 residues (deduced molecular mass 54,229 Da). The recombinant enzyme showed the maximal activity at 60-65 degrees C and pH 11.

[Digital X-ray apparatus "Sibir'". Measurement of the value of a signal].

For objective measurement of digital detectors, the authors show it necessary to be limited to the quantum efficiency of recording for assessing the accuracy of measuring the value of a signal and to the frequency-contrast characteristics for estimating spatial accuracy. Since a computer is an integral part of the digital detector, this cannot be a basic obstacle to the application of the proposed procedure.

[The proline biosynthesis gene proA from the thermophilic bacterium Thermus ruber: its cloning, sequencing and heterologous expression].

The proA proline biosynthesis gene of thermophilic bacterium Thermus ruber was cloned and sequenced, and several properties of the encoded enzyme, gamma-glutamylphosphate reductase (GPR) were studied. The proA open reading frame (ORF) was of 1286 bp. Nucleotide sequence analysis revealed the ATG initiation codon in position 36 and the TTA termination codon in position 1304.

[A digital radiographic device for medical diagnosis].

The paper outlines a digital radiographic device which records radiation by scanning with a one-dimensional multiwire proportional chamber connected on-line to a computer. The device drastically reduces a dosage load on patients, improves the diagnostic potentialities of projectional radiography, yields quantitative diagnostic information, creates special diagnostic programmes, has fast-access and fire-safe archives. The device may be used for general-purpose radiographic examinations and it has advantages when used instead of conventional fluorographs.

[Relaparotomy: determination of the indications and results].

The indications for relaparotomy in cases of bleeding, peritonitis, acute ileus and abdominal abscess were determined. Using the indications gave a possibility to perform the relaparotomy on 1-st postoperative day right after first signs of those complications. The mortality dropped from 46% to 20.

[Extracorporeal detoxification using heterologous spleen in acute pancreatitis].

The method of extracorporal connection of the swine spleen (ECSS) was used in the complex treatment of 32 patients with acute pancreatitis. Three patients died. It was established that ECSS effectively reduced hyperfermentemia and increased the phagocyte activity of blood leukocytes which was an important component of complex treatment of patients with acute destructive pancreatitis.

[Immunological and morphological properties of in vitro transformed fibroblasts. III. Recognition by macrophages and activated lymphocytes of mouse and rat cells of various degrees of tumorigenicity].

Data are provided on the development of tumorigenicity in cells of 6 independently produced lines of mouse and rat embryonic fibroblasts during their prolonged passage in vitro. The data on the development of lysis of these cells by macrophages and activated lymphocytes during the same passage indicate that enhanced cell lysis of cells by natural effectors and, hence, cell recognition by them may be regarded as an obligatory manifestation of cell malignization.

[Nucleolus-forming regions in the chromosomes in continuous cell cultures].

Localization of nucleoli-forming (NF) areas in chromosomes of continuous cell cultures of African green monkey kidney Vero, CV-1, GMK, BGM, BS-C-1. Macaca rhesus kidney LLC-MK2, dog kidney MDCK, pig kidney SPEV, PK-15 was studied. The NF-areas in chromosomes of African green monkey, M.

[Immunological and morphological properties of fibroblasts transformed in vitro. II. The change in the susceptibility of FC3H3 cells to lymphocytes--natural killers and macrophages during their selection for malignancy].

The previous report contained the information on obtaining in vitro continuous cell lines of embryonic fibroblasts of mice of 4 genotypes, including C3H. In this paper, data on the degree of lysis of some derivatives of FC3H3 cells by natural killers and macrophages are given. It was shown that normal cells were not lysed by these effectors unlike cells which overcame Hayflick's limit and got minimum malignancy in vitro.

[Immunological and morphological properties of fibroblasts transformed in vitro. I. The isolation of continuous mouse cell lines, their malignancy, H-2 antigens and complement sensitivity].

7 continuous cell lines with different degrees of malignancy were obtained from cultures of embryo fibroblasts of 4 strains of mice. Three of them were selected in vivo for enhanced malignancy. A study of regularities of changes in immunologic and some cytologic characteristics of these cells in the processes of transformation and malignization has been started.

[Development of a cellular immune response in a highly cancer-susceptible C3H/He strain of mice and its nonfactor substrain C3H/f after the transplantation of a syngeneic mammary gland tumor].

Syngeneic mammary gland tumor (MMT-1) grew slower in non-factor C3H/f (MTV-L) mice than in wirus-positive C3H/He (MTV-S) mice. The immunization of mice with tumor (MMT-1), inoculated and later excised, revealed a higher immune reactivity in the mice of the non-factor substrain. In studying the dynamics of the cytotoxic activity of lymphocytes in regional lymph nodes cytotoxically active lymphocytes were found to appear in C3H/f mice on day 6 after the inoculation of tumor (MMT-1), while the areactive state of lymphocytes was observed in C3H/He mice on days 3 and 24 and in C3H/f mice on day 24 after the inoculation of tumor (MMT-1).

[Genetic determination of the immune response of mice to cells of various histological types].

The intensity of the immune response of cells in mice to strong transplantation antigens of the H-2 complex can depend on the histological type of cells taken for immunization. Splenic cells of C3H mice immunized the cells of BALB/c line better that cells of the non-lymphoid origin taken from the same donor. A reverse situation was observed in case of immunization by the same cells of the lines C57Bl/6 and A/He.