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Biomedical subjects

A M Borodin

Publications and source records attributed to A M Borodin.

At least 19 recordsLinked to original sources

[PCR-based diagnostics of community-acquired pneumonia of mycoplasmal and Chlamydia etiologies].

Two hundred and ninety-two patients with pneumonia evidenced by clinical, X-ray and laboratory findings were examined for the purpose of studying the etiological significance of Mycoplasma pneumoniae and Chlamydophila pneumoniae--atypical pathogens; the patients, members of closed bodies, were admitted to the hospital for as long as one year. PCR was used to examine the sputum of patients who were at exacerbation. It was established that the mentioned pathogens prevailed in autumn and winter. It can be concluded, on the basis of a PCR-based monitoring of the atypical pathogens, that the significance of the atypical pathogens within the etiological structure of pneumonia acquired in isolated collective by young persons has been on the rise.

Chlamydophila Infections↗

[Construction of a mapping panel of human-rodent hybrid cells].

A clone panel of 27 human-Chinese hamster and 4 human-mouse somatic cell hybrids which contained as minimum five discriminating clones for any chromosome pairs was set up. Segregation analysis of 45 human chromosome-specific isoenzymes and PCR markers in hybrid clones allowed to demonstrate a possibility to apply the obtained panel for chromosome mapping of human genes.

Animals↗

[Use of the polymerase chain reaction for analysis of rotaviruses. Nucleotide sequence of a gene, coding for the basic neutralizing antigen VR7 of a human rotavirus with a new G-serotype].

A procedure based on polymerase chain reaction use for the detection of rotavirus has been developed. Full length cDNA copy of the VP7 gene coding for the major neutralization glycoprotein of the human rotavirus RK9 with an unusual "wide" electrophoretype is cloned and sequenced. Glycoprotein VP7 of RK9 has a unique amino acid composition in A and C antigenic regions. It shows that strain RK9 represents a new (12) rotavirus serotype.

Amino Acid Sequence↗

[Rare initiation codons are regulators of expression of the rpoC gene].

Translation of the rpoC genes in Escherichia coli and Salmonella typhimurium is known to start from the GUG codon. Now, using toeprint analysis we have shown UUG to be the initiation codon of the Pseudomonas putida rpoC gene. IF3 does not seem to proofread initiation at the UUG codon. The rpoC genes of P. putida, E. coli, and S. typhimurium, which use rare start codons, have strong SD-domains AGGAGG (P. p.) and GGGAG (E. c., S. t.), optimal seven-nucleotide spacing between SD and start codons, and good second codon AAA. We suggest that rpoC presents an infrequent case of the regulation of translation initiation by selecting the start codon.

Base Sequence↗

Effective method for obtaining long nucleotide chains on partially complementary templates. Processed bovine gamma-interferon gene obtained from human gamma-interferon gene.

The method of obtaining the bovine gamma-interferon gene by means of simultaneous multidirected mutagenesis of the human gamma-interferon gene is presented. The first strand of the bovine gamma-interferon gene was obtained by ligation of synthetic oligonucleotides, using the cDNA of human gamma-interferon, cloned in the single-stranded phage M13mp19 as a template. The second strand was synthesized using a large fragment of E. coli DNA-polymerase I. The double-stranded gene was then treated by restriction nucleases and cloned in a pUC-18 derived vector. The primary structure was confirmed by sequencing.

Animals↗

[Isolation of the porcine alpha-interferon gene using simultaneous directed multipoint mutagenesis].

A method of obtaining the pig alpha-interferon gene by means of simultaneous multidirected mutagenesis of the human alpha 2-interferon gene is presented. Nucleotide homology between these genes is 80.4%. Fourteen synthetic oligonucleotides forming a pig alpha-interferon gene's strand were ligated on a single-stranded template, carrying cDNA of the human alpha 2-interferon gene. The obtained DNA fragment was cloned in the single-stranded or double-stranded form. It was found that the method does not affect the cloning efficiency. The primary structure of the gene was confirmed by sequencing.

Amino Acid Sequence↗

[Amino acid substitutions in the beta-subunit of RNA-polymerase from E. coli compensating for mutation-induced damage of the rho termination factors].

Ts-phenotype of the E. coli rho-factor mutant rho 15 is suppressed by two rifampicin-resistance mutations, rhoB1019 resulting in a single amino acid substitution Val146----Phe and rhoB268 resulting in a single substitution Gln513----Leu in beta-subunit of the E. coli RNA polymerase. Rifampicin-resistance mutations rhoB255 (Asp516----Val), rhoB1016 (Asp516----Asn), rhoB1001 (His526----Tyr), rhoB1004 (Ser531----Phe), rhoB1005 (Pro564----Leu), and streptolydigin-resistance' mutation rhoB1018 (double substitution Gly544----Asp and Phe545----Ser) do not suppress the rho15 mutation.

DNA-Directed RNA Polymerases↗

Results of cosmic radiation dose field measurements aboard the "Salyut-6" orbital station.

During the 3rd main expedition on board the "Salyut-6" orbital station in 1979 the integral characteristics of cosmic radiation were measured in various positions inside the manned modules (experiment "Integral"). Measurements were performed with thermoluminescent dosimeters, photographic films and solid state plastic detectors supplied for the experiment by specialists of the USSR, Bulgaria, Hungary, GDR and Romania. The dose gradient inside the manned modules of the station amounted to 70% for long intervals of time. During the experimental period the dose rate inside the station was 15 to 30 mrad per day. The mean flux of particles with Z > or = 6 and LET > or = 200 keV/micrometer was found to be 0.22 cm-2 or day-1.

Cosmic Radiation↗

[Anaerobic degradation of biphenyl by the facultative anaerobic strain Citrobacter freundi BS2211].

Using a synthetic medium supplemented with biphenyl (a polycyclic aromatic hydrocarbon), a new bacterial strain of Citrobacter freundii was isolated from enrichment cultures containing soil and industrial wastewater samples of the Serpukhov Condenser Factory. This strain was found to be capable of degrading biphenyl under anaerobic conditions in the course of nitrate reduction. When the initial concentration of biphenyl in culture medium equaled 150 mg/l, the culture with a titer of 10(9) cells/ml degraded up to 26-28% of biphenyl in 3 days (28 degrees C). At 250 mg/l, the culture with a titer of 10(7) cells/ml degraded 15% of biphenyl in 21 days. Approximately 10% of the substrate consumed was utilized completely, whereas the remainder underwent transformation.

Anaerobiosis↗

[Detection of Mycoplasma pneumoniae and Chlamydophila pneumoniae in patients with community acquired pneumonia].

A total of 292 patients with pneumonia confirmed by clinical, roentgenological and laboratory methods, admitted to the hospital from closed communities during the one year period, were examined. The sputa of patients with pneumonia in the acute stage were studied in the polymerase chain reaction (PCR). The predominence of M. pneumoniae and C. pneumoniae causualties in autumn and winter period was established. The monitoring of atypical infective agents with the use of the PCR techniques gives evidence for conclusion on their ever growing role in the etiological structure of community acquired pneumonia in groups of closely interacting young people.

Chlamydophila pneumoniae↗