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Biomedical subjects

A A Vorob'ev

Publications and source records attributed to A A Vorob'ev.

At least 19 recordsLinked to original sources
PubMed2006

[The microbiological and immunological characteristics of disbiotic disturbances of the biotopes of the mucose membranes of the respiratory and urogenital tracts].

The study consisted in comparison of the microecology and the parameters of the humoral immunity of the biotopes of the respiratory and urogenital tracts under normal conditions and in inflammatory processes caused by bacterial agents. The study revealed significant changes in the microbiocenosis of the respiratory and urogenital tracts, caused by decline of indigenous microflora and increase of the content of conditionally pathogenic microorganisms. These changes depended on the degree of the infectious process severity. Measurement of the humoral immunity parameters revealed a significant correlation between the content of conditionally pathogenic microorganisms and the levels of M and A immunoglobulins, as well as secretory IgA and free secretory component (sc) in the vaginal secretions of patients with non-specific inflammatory diseases of the genital tract, as well as G and A immunoglobulins, secretory IgA, and sc in the saliva of patients with chronic inflammatory diseases of the respiratory tract.

Adolescent↗
PubMed2006

[A study of human fecal microbiocenosis by experimental in vitro modeling of constipation].

A study of human fecal microbiocenosis using experimental in vitro modeling of constipation was carried out. The study revealed certain dynamics of the incidence, proportion and ratio of microorganisms isolated from the feces at various stages of cultivation. The character of the changes of these parameters depended on the type of the microorganism. According to the results of the experiment, transitory flora (staphylococci; candidas) begins to disappear within the first day of cultivation. If intestinal evacuation is retarded for more than 2 or 3 days, distortion of the microbiological characteristics of the residential microflora, bifidobacteria and escherichiae, is possible. These processes may lead to a false positive result of dysbiosis analysis. The authors conclude that dysbiotic changes in constipation are caused by fecal retention. That is why correct diagnostics of dysbiosis is possible only after regular everyday stool is reestablished.

Adult↗
PubMed2006

[The adhesive properties of lactobacteria and escherichiae in different divisions of human gastrointestinal tract under normal and pathologic conditions].

A comparison of the adhesive properties of lactobacteria and escherichiae in different divisions of human gastrointestinal tract under normal and pathologic conditions was conducted. The study shows that the population changeability of the adhesive properties of lactobacteria and escherichiae is determined by localization of the strain in the gastrointestinal tract, and morphofunctional condition of the intestinal wall. Bacteria's adhesiveness to glycocalix of intestinal epithelial cells is higher in the left half of the colon than in the right one, and is still higher in feces. Their co-adhesiveness changes in the reverse order. Bacteria localized in the parietal mucin of inflamed segments, possess low capability of forming microcolonies, and high adhesiveness to glycocalix. The results of the study demonstrate that the choice of therapeutic probiotic bacterial strains should depend on the anatomic localization of the lesion and the character of gastrointestinal pathology.

Adult↗
PubMed2006

[The bacterial QS-systems and prospects of creation of new metabolic probiotic preparations].

Biological functions of exometabolits of various bacterial species were analyzed from Quorum Sensing position, which showed that the functional activity of microbiocenosis is in many respects determined by the system of metabolic regulation. Possibility of changing the composition of complex microbial communities with low-molecular compounds, products of bacterial cell vital activity, is grounded from theoretical point of view. The authors adduce data on the effects of a synthetic composition on the basis of E. coli metabolites, an ingredient of colibacterin, a probiotic preparation. The preparation demonstrated a high stimulating activity towards a range of microorganisms of normal microflora, and an ability to improve the condition of intestinal epitelial cells. The results may substantiate application of metabolic probiotics for correction of intestinal microflora in man.

Bacterial Physiological Phenomena↗
PubMed2006

[A study of parietal gastrointeatinal microflora of rats after oral administration of probiotics].

The article is dedicated to one of the topical problems of medical microecology, possibility of modification of parietal gastrointestinal microflora by oral administration of various probiotics, and evaluation of the effects of such modification. The results of the study show that parietal gastrointestinal microflora can be modified by oral administration of probiotics.

Administration, Oral↗
PubMed2006

[Comparison of the methods of evaluation of the microbiological danger of antimicrobial agents by the example of oligo- and polyguanidines].

The article contains the results of comparison of the methods of evaluation of the microbiological danger of antimicrobial agents by the example of oligo- and polyguanidines. The study demonstrates that choice of an adequate study model (a bacterial or protozoa species) and exposure time depends on the characteristics of the preparation to be tested. It shows that the microbocide activity of polyguanidines should be studied on a bacterial model using long (24 hours) exposure. The most sensitive to XG6 was a protozoa culture in short-time exposure. To evaluate the biological danger ofantimicrobial agents, it is also possible to apply techniques that allow revealing reversable physiological changes in a culture of test objects.

Animals↗
PubMed2006

[The anti-infective resistance system in women with chronic urogenital inflammatory diseases of chlamydia ethiology].

A complex clinico-instrumental and immuno-microbiological examination of 433 reproductive age women was performed. The results show that a lingering and relapsing chlamydian infection in women with an exacerbation of a chronic inflammatory urogenital disease develops against the background of disturbances in the anti-infective resistance system (AIRS), and is characterized by combination of chlamydian infection with other sexually transmitted infections and the presence of dysbiosis. The immunological aspects of this process consist in almost a total absence of neutrophiles' ability to digest a bacterial antigen, and incompleteness of phagocytosis, in general. These changes may be connected with a low immunogenicity and intracellular parasitizing of chlamydiae, on the one hand, and with primary incompetence of the subjects' AIRS, on the other. From a microbiological point of view, this is manifested by complete combined urogenital and colon dysbiosis.

Adult↗
PubMed2006

[The topicality of return to smallpox vaccination: problems and prospects].

Nowadays there are certain facts which evidence the necessity of return to smallpox vaccination in Russia, especially concerning people who will be engaged in the liquidation of the nidi of this infection, should such appear. Smallpox virus is kept in laboratories of some countries; there is a real threat of biological terrorism; population immunity to smallpox infection is virtually absent. Considering the present situation in development and production of smallpox vaccines and remedies against vaccine-related complications, the tactics of population vaccination in Russia may vary. The main problems concerning return to smallpox vaccination in Russia are the following: there are no modern schemes (schedules) of smallpox immunization; there are no currently available and safe vaccines for primary immunization of adults; there are no preparations for prevention and treatment of vaccine-related complications. Thus, the priority areas are: development of effective and safe oral adult vaccines for primary immunization; production of human and heterologous immune globulins and their storage.

Administration, Topical↗
PubMed2006

[The role of regulatory cells CD4+CD25+ in the development of chronic infective diseases].

Regulatory T-cells CD4+CD25+Foxp3 (Treg) present a small subpopulation of CD4+ T lymphocytes, which develop in the thymus and are disseminated into peripheral lymphoid organs on the 3rd or the 4th day of the neonatal period. Treg play a decisive role in the pathogenesis of autoimmune diseases and the development of tolerance to transplantation antigens, regulate the immune response to allergens, and suppress antimicrobial immunity. Treg suppress proliferation as well as the cytotoxic effect and the secretion of Th1 and Th2 cytokines by effectory T lymphocytes, thus limiting the strength of the immune response of effectory T-cells, which makes them impossible to adequately control viral and bacterial infections. Recognition via antigen-presenting cells and the subsequent induction of the proliferation of antigen-reactive T and B lymphocytes, directed towards infectious agent elimination, is accompanied by the activation of regulatory T cells as well, which leads to immune response suppression; repeated microbial infections are not only able to strengthen T-cell immunity by generating memory T-cells, but can also strengthen the suppressive activity of endogenous T regulators CD4+CD25+. Moreover, T reg are capable of the direct recognition of a microbial product; these cells selectively express Toll-like receptors (TLR)-2, -4, -5, -7, and -8. Under normal conditions T reg are anergic, but are capable of direct proliferation in response to stimulation by TLR ligands, expressed on microbes and parasites. Treg removal enforces protective immune response to contagious microorganisms, including bacteria, viruses, and fungi, which leads to the elimination of pathogens from the host organism. The removal of Treg population will help to accomplish infectious pathogen elimination and diminish inflammation within a short period of time.

Animals↗
PubMed2006

[Study of the influence of Staphylococcus aureus on gastrointestinal tract microbiocenosis in rats].

The authors studied the modifying effect of Staphylococcus aureus on the microbial composition of gastrointestinal tract microbiocenosis. The subjects were female rats in the condition of eubiosis or dysbiosis. The species and quantitative composition of the fecal microflora and the parietal mucin in different parts of the intestine were studied after an intragastral administration of St. aureus suspension. A single introduction of St. aureus into the gastrointestinal tract of rats led to the appearance of this microbe in the feces and parietal mucin in all the parts of the intestine regardless the initial condition of the intestinal microbiocenosis. The indigenous microflora, both in eubiotic and dysbiotic conditions, practically did not respond to an intragastral administration of staphylococcus, except a little decrease in the proportion of bifidobacteria. Meanwhile, there was a significant increase in the incidence of candid detection. The indigenous parietal microflora changed more substantially, which demonstrates a higher sensitivity of the parietal microbiocenosis to a short-time exposure to an exogenous microbial factor.

Animals↗
PubMed2005

[Genetic vaccines].

Vaccination with DNA-vaccines is a new approach in immunization that implies application of genetic constructions coding certain proteins of various pathogens instead of conventional ways of vaccination with inactivated or attenuated microorganisms. The main advantage of this approach consists in possibility to induce immune response in cases when the disease cannot be prevented by routinely used prophylactic vaccines. This advantage is attributed to the ability of DNA-vaccines to focus immune response (cellular, humoral or both) upon one or several certain pathogenic antigens, which is impossible in principle when conventional vaccines are used and does not occur during an infectious process. The efficiency of DNA-vaccines is currently being tested in various pre-clinical and clinical trials. Genetic vaccination has induced protective or therapeutic immune response in a significant number of these trials. However, despite numerous positive results, clinical use of DNA-vaccines has not been recommended yet.

Animals↗
PubMed2005

[Evaluation of diagnostic criteria of syphilitic infection by means of gas chromatography and mass-spectrometry].

In order to estimate possibility of chromatographic criteria application in diagnostics of syphilitic infection, the authors researched in three directions: evaluation of dysmetabolism of carbohydrate, lipid and amino acid components in patients' serum; search of signal compounds that serve as microbe "cooperative sensitivity" activators (lactones, quinolones, furan boron ethers) with evaluation of the risk of luetic infection generalization; indication of organ lesion markers (the brain, liver, bone structures). The factor analysis performed by the researchers allowed to determine priorities of clinical, laboratory and chromatographic data according to their value. The diagnostic value of various diagnostic chromatographic criteria was estimated as follows: the diagnostic sensitivity was 79.6% to 97.2%, the diagnostic specificity was 50.0% to 92.7%, the positive diagnostic predictability was 61.8% to 94.7% and the negative diagnostic predictability was 60.9% to 95.1%.

Amino Acids↗
PubMed2005

[Potentialities of preoperative chest computed tomography in patients with pulmonary tuberculosis].

The data on 120 patients prepared for surgery for pulmonary tuberculosis were analyzed. Based on the results obtained after computed tomography (CT), the authors received additional information in 86 (71.7%) patients, resulting in changes in surgical tactics in 41 (34.2%) patients, delay of surgery in 33 (27.5%), and its cancellation in 12 (10%). It should be concluded that it is necessary to use chest CT in patients with pulmonary tuberculosis at the preoperative stage.

Adult↗
PubMed2005

[Formation of probioticotherapy in Russia].

Probioticotherapy and probioticoprophylaxis have been applied widely in Russia and the world of late. The article presents the main medical, strain-related, and biotechnological stages of their development in this country, in comparison with the results of the world practice. The authors substantiate appropriateness of creation of probiotics and which would contain either only growth medium components, able to activate normoflora (to increase colonization ability and stimulate production of biologically active substances) upon entering the organism, or only probiotic strain components and/or biologically active substances produced by biologically active strains in mono- or associative cultivation, or combination of the listed components.

Food Industry↗
PubMed2005

[Risk control strategy in the sphere of circulation of pharmaceuticals].

The article deals with classification of pharmaceutical risks and methodical approaches to their control in the system of governmental regulation of pharmaceuticals. According to the origin of risks and possibilities of their control, the authors distinguish "outer risks", not controlled by a consumer, and "inner risks", whose probability can be lowered by a consumer. Among the "outer risks" there are systematic risks, expressed by probability of adverse effects, and diversified risks, associated with pharmaceutical quality, practice of their administration and application, and partly--with insufficient knowledge of them. As an example the authors analyze risks associated with pharmaceutical quality of medicaments withdrawn from drug-stores by Ministry of Health of Russian Federation. In order to control such risks, the authors offer classification of pharmaceuticals according to the degree of controllability of manufacturing process, the ways of administration of a pharmaceutical (pharmaceutical dosage form), the severity of harm that can be caused to a consumer due to a defect not revealed by the manufacturer, and the degree of risk for population health. The authors reckon that the methodical approaches to pharmaceutical risk control may be used in evaluation of existent mechanism of providing safety for a pharmaceutical consumer, as well as in development of State strategy of increasing pharmaceutical safety.

Drug Industry↗
PubMed2004

[Factors and conditions affecting the process of infecting the fetus during different pregnancy stages].

Etiology, pathogenesis of intrauterine infection of the fetus, factors promoting such infection and the status of the local immune system are elucidated in the paper. A changed reactivity of the immune homeostasis of a pregnant woman with a chronic infection was shown to be potentially an important factor of pathogenesis of defects in her baby. The local immunity factors of the reproductive tract, i.e. the vagina and neck of uterus, are in the forefront of anti-infectious protection, which signal an alert or limit the microorganisms' reproduction; besides, they prevent the microorganisms from penetrating into the upper genitals. The therapeutic-and-preventive schemes applicable to infected women must comprise measures targeted at eliminating an infectious agent and at normalizing the pathological changes in the performance of the immune system activity.

Amnion↗
PubMed2004

[The microecological disorders in clinical pathology and their correction by bifidum-containing probiotics].

On the basis of independent research and published data surveyed in the paper is the prevalence and nature of disorders of the intestinal microflora observed in adults and children with different pathologies, i.e. chronic diseases of the gastrointestinal tract, acute intestinal infections, acute respiratory viral infections, pneumonias, as well as certain nephrological, gynecological, and surgical diseases etc. The deficit of Bifidobacteria was found to be the most frequent chain in intestinal microflora pathologies. The significance of Bifido-containing drugs as well as current research of Russian scientists, including new probiotics with Bifidobacteria immobilized in coal, is elucidated. The advantages of intestinal dysbacteriosis correction by sorbated Bifido-containing probiotics, like bifidumbacterin forte and probifor, are demonstrated, versus bifidumbacterin, in different pathologies; their related clinical-and-morphological effect is defined. Prospects for designing the combined and polyvalent drugs with immobilized Bifidobacteria are described.

Adult↗