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V A Potapov

Publications and source records attributed to V A Potapov.

At least 19 recordsLinked to original sources
PubMed1999

[Feasibility of decreasing the adhesive activity of Corynebacterium diphtheriae by biopolymers of natural origin].

Possible decreasing of the Corynebacterium diphtheriae adhesive activity by natural biopolymers was studied. It was shown that the strains of C.diphtheriae circulating on the Primorye Territory had middle, low or minimal adhesive activity. Natural biopolymers were found to decrease the adhesive properties of C.diphtheriae. The results of the study are promising for further investigation of natural biopolymers as agents preventing C.diphtheriae colonization on the stomatopharynx mucosa.

Bacterial Adhesion↗
PubMed1992

Species- and tissue-specific transcription of complex, highly repeated satellite-like Bsp elements in the fox genome.

We have studied the transcription of highly repeated satellite-like Bsp elements containing the potential promoter boxes for RNA polymerase III in the genomes of adult silver and arctic foxes. The Bsp repeat transcripts were abundant enough to be detected by Northern blot and semiquantitative dot blot hybridizations, and the majority were found in the nuclear RNA fraction from arctic fox kidneys. Weak hybridization signals were revealed with the cytoplasmic RNA preparation from silver fox kidneys and with the nuclear RNA fraction from arctic fox liver, and their intensity was intermediate with the total RNA from arctic fox brain. Taken together, the data suggest possible genomic interspersion of some Bsp repeats in these two representatives of Canidae. The observed species-and tissue-specificity of the transcription of Bsp repeats suggests that they may potentially accomplish regulatory functions in the fox genomes.

Animals↗
PubMed1992

[State of nonpulmonary tuberculosis care in West Siberia].

Basic epidemiologic parameters in relation to extrapulmonary tuberculosis were analysed in 6 regions of West Siberia as well as the state of the material-technical base of extrapulmonary service in these areas. Despite a general reduction of the revealed incidence and morbidity of extrapulmonary tuberculosis, the true incidence persists at a high level with predominance of advanced forms of the process. One of the causes of this situation is insufficient material-technical support of extrapulmonary tuberculosis service in West Siberia.

Humans↗
PubMed1991

[Species-specific features of the distribution of restriction sites in Bsp-repeats of Canidae genome].

Differences and similarities of the Bsp-repeats' organization in fox, dog, polar fox and raccoon dog genomes were studied. Specificity of Bsp-repeats to the Canidae family was demonstrated. The repeats are mainly organized in large clusters in all species studied. The species-specific features in restriction patterns were revealed for all five genomes, in spite of high intragenomic polymorphism exhibited in each case. This suggests that certain unique sets of structural versions of Bsp-repeats were fixed in canid genomes by amplification during the process of speciation. Fox and polar fox exhibited the highest similarity in restriction patterns of Bsp-repeats. Raccoon dog pattern is most unusual among others: its distinguishable character is the absence of large multimeric series. The EcoRI hydrolysate of raccoon dog Bsp-repeats consists mainly of one band corresponding to 1600 bp. These are in accordance with phylogenetic relations between canids.

Animals↗
PubMed1991

[Heterogeneity of the Canidae Bsp-repeats family: discovery of the EcoRI subfamily].

A 1600 bp EcoRI fragment was cloned from genome of raccoon dog. The structure obtained is homologous to the Canidae Bsp-repeats family. Comparative blot hybridization of the EcoRI fragment and BamHI repeat from fox genome with restricted hydrolysates of the total of raccoon dog and fox DNAs revealed differences both in structure and genomic organization between these two Bsp-repeats versions. Evidently, the EcoRI fragment contains a sequence lacking from the BamHI fragment of the fox Bsp-repeats. Quantitative differences in contents of two Bsp versions in various canid genomes were revealed as well. The EcoRI version is most abundant in raccoon dog genome, while the BamHI fox version is most representative in polar fox genome. With other species studied, quantitative differences in version contents are not so dramatic, and the EcoRI fragment is always present in lower copy numbers. The discovery of the EcoRI subfamily of the Bsp-repeats is in accordance with the "library hypothesis" advanced by Salser in 1976. Connection of the Bsp-repeats' evolution with centric fusions and breaks characteristic of karyotype evolution of canids is being discussed. Comparative study of cloned EcoRI and BamHI fragments of Bsp-repeats in cytogenetical and molecular aspects may be useful, when investigating the role of tandem repeats in large chromosome rearrangements.

Animals↗
PubMed1990

[Clinico-morphological evaluation of pathogenetic mechanisms of bouginage and intubation on cicatricial esophageal stenosis after chemical burns].

The article deals with the clinico-morphological appraisal of bougienage and intubation of patients with cicatricial constriction of the esophagus after chemical burns. Endoscopic and morphological studies were carried out in 38 patients before and during treatment. Bioptic material collected from the esophageal mucosa was studied on a light-optic and ultrastructural level. The results of the study showed that bougienage of the epithelialized strictures causes protracted stimulation of intracellular regenerative processes and thus facilitates the development of leukoplakia of the squamous epithelium. The prevention of esophageal precancer in this case consists in radical maintenance bougienage and regular medical examination. Bougienage of ++non-epithelialized strictures stimulates the formation of young granulation tissue, while subsequent intubation stimulates reparative processes, creating in this manner conditions for adequate epithelialization of the ulcerated esophageal strictures.

Burns, Chemical↗
PubMed1989

[Organization of Bsp-repeats in the fox genome].

Bsp repeats comprise approximately 1% of silver for total DNA and are preferentially localized in centromeric regions. Two of Bsp fragments cloned earlier, such as non-homologous rsV1 and rsV3, make up together a Bsp unit (680 bp) and possess a set of sites known to have regulatory functions in eucaryotic genomes. In this work, tandem organization of Bsp repeats is demonstrated. A stretched Bsp sequence (approximately 1460 bp, dimeric form) flanked by BamHI sites was cloned and its restriction map was plotted. With use of rsV1 and rsV3 probes the new sequence exhibited linked structure: rsV1-rsV3-rsV1-rsV3-rsV1. Blot-hybridization with the restriction fragments of fox total DNA suggested hierarchical order of Bsp clustes in the genome. It is supposed that the processes of selective amplification of individual fragments had been of real importance during evolution of Bsp repeats.

Animals↗
PubMed1988

[Surgical treatment of chronic biliopancreatitis].

Surgical treatment of chronic biliopancreatitis has sometimes unsatisfactory results of cholecystectomy and supraduodenal choledochoduodenoanastomosis due to non-eliminated during the operation chronic alterations of the patency of terminal parts of the common bile duct and Wirsung's duct. In most patients with chronic biliopancreatitis good and satisfactory results were noted after performing associated surgical operations including cholecystectomy, transduodenal papillosphincterotomy, wirsungoduodenotomy, correction of duodenostasis and splanchnicectomies.

Adult↗
PubMed1988

[Electron microscopic verification of adenocarcinoma of the cardioesophageal area].

Normal gastric and esophageal cardiac glands as well as proper esophageal glands were studied electron-microscopically. Cardiac gastric and esophageal glands were found to differ by chief cells available in the gastric glands and greater amounts of endocrine cells registered in the esophageal glands. The evidence can provide grounds for electron microscopic verification of cardioesophageal adenocarcinoma permitting the pathologist to rest upon the presence of cells resembling those of proper gastric glands and epigastric fossa. In addition, it can promote specification of the morphologic type of adenogenic esophageal cancer comprising squamous epithelial component and secretory granules typical of proper esophageal glands.

Adenocarcinoma↗
PubMed1987

[Histological and ultrastructural characteristics of esophagitis in chronic kidney failure].

Examination of biopsy specimens secured during endoscopy of 70 patients in the terminal stage of chronic renal failure revealed abnormalities characteristic of chronic esophagitis, viz. hyper- and parakeratosis, basal-cell proliferation, acanthotic outgrowths, epithelial thickening, vacuolated cells (with balloon cells being present in some cases), presence of calcium crystals, cisternal widening in the rough endoplasmic reticulum, and mitochondrial swelling with cytoplasmic rupture and hyaloplasmic edema. These dystrophic changes may account for the relatively frequent occurrence of erosional and ulcerous lesions in the esophagus during the terminal stage of the disease.

Adolescent↗