Search PubMed⌕ Search

Biomedical subjects

A B Daĭter

Publications and source records attributed to A B Daĭter.

At least 19 recordsLinked to original sources
PubMed1993

[The dynamics of the metabolic and functional activities of the immunocompetent cells in mice following immunization with different vaccines against Q fever].

It was shown that the immunization of mice by the chemical Q fever vaccine prepared with the use of the strain "Coxiella burnetii, Nine Mile", phase I did not markedly activate the oxidative metabolism of the peritoneal exudate cells and did not induce the non-specific cytotoxicity in them. However, it resulted in a significant suppression of the mitogen-induced proliferation of splenocytes on days 3-5. The immunization of mice by the combined (corpuscular/chemical) vaccine prepared with the use of the strain "Apodemus flavicollis-Luga", phase I induced a significant activation of the oxidative metabolism of the peritoneal exudate cells and the development of the nonspecific cytotoxicity in them, whereas no suppression of the mitogen-induced proliferation of splenocytes was observed. The differences are likely associated with the presence of the corpuscular component in the combined vaccine and the strain antigenic specificity.

Animals↗
PubMed1991

[The host reaction to the administration of different components of Coxiella burnetii].

After the intraperitoneal injection of corpuscles of C. burnetii antigen (Ag), phospholipid (PL), and sediment obtained after the extraction of PL from Ag with chloroform-methanol (CM) slight leukocytic reaction developed in the peritoneum on day 1, and on day 2 it could be observed in the liver and in the spleen. Ag induced the most pronounced morphological changes. In the spleen they were manifested by the activation of T- and B-dependent zones of white pulp from day 2 and by the pronounced hyperplasia of reticular cells and macrophages, leading to splenomegaly, by days 7-14. Simultaneously lymphoid-macrophagal granulomas and hepatomegaly developed in the liver. By days 7-14 the foci of necrosis in the liver were caused by the thrombosis of portal veins and were not registered after the injection of PL and CM (and earlier also in experiments with Ag in doses of 0.1-0.3 mg).

Animals↗
PubMed1991

[An immunoenzyme method for demonstrating Coxiella burnetii antigens].

Materials on the development of an enzyme immunoassay (EIA) system for the detection of the antigens of C. burnetii, the causative agent of Q rickettsiosis, are presented. The system is highly specific and effective with respect to both corpuscular antigens of phases 1 and 2 and soluble antigen (lipopolysaccharide). The sensitivity of this method varies within the range 5-100 ng/ml. The effectiveness of EIA as a quantitative (semiquantitative) control test used in the process of the production of Coxiella preparations has been demonstrated.

Animals↗
PubMed1989

[Immunogenic and immunomodulating properties of phospholipids from Coxiella burnetii].

It is proved that the challenging of the extract isolated from Coxiella (as a result of treatment with the mixture of chloroform and methanol) to animals doesn't provoke the appearance of antibodies to these microorganisms. It also doesn't cause the sensibilization of lymphocytes to Coxiella, but the extract can interact specifically with a serum containing antibodies to Coxiella. It permits to characterise the tested extract of Coxiella as a hapten with properties of adjuvant because it stimulates antibody-appearance.

Adjuvants, Immunologic↗
PubMed1989

[The epidemiology of Q fever].

Q fever as one of infections with natural foci is characterized by epidemic outbreaks. Biologic plasticity and ecologic peculiarities of Coxiella determine its wide distribution and development of Q fever infections which are disseminated almost every-where. They occur in two, i. e. natural and agricultural types of foci. Present paper characterizes their structures, maintenance and peculiarities if their existence. It should be emphasized that single cases of disease as well as outbreaks of Q fever originate usually from agricultural foci, where the source of the infection are livestock, sheep and goats. Data are presented on the involvement of these animals into circulation of coxiellae in various countries of the world. It was shown that agricultural foci of Q fever depending upon close connection with domestic animals are determined in many aspects by basic factors of an epidemic process of the infection, i. e. seasonal occurrence, social conditions, professional relations, etc. which also enhance the course of the infection. Principles on prophylaxis complete the given paper.

Animals↗
PubMed1989

[Ixodid ticks and rickettsia].

Ixodid ticks are an important link in the ecology of rickettsiae. Some tick species became specific vectors as well as reservoirs of certain species of rickettsiae ensuring their long lasting maintenance via interstadial and transovarial transmission often over generations in nature. To now many significant questions on relationship between ticks and rickettsiae became clear, however, most of them still remain to be elucidated. The open question, for instance, involves the data on the differences in sensitivity of various tick species to a certain species of rickettsiae what has its significance concerning the transmission of an agent to a host. Intracoelomal injection of a tick with rickettsiae does not solve its role as a vector in nature, because the main natural barrier of tick organism against pathogens, i.e. alimentary tract with its specific biochemical properties, has been avoided. To specify a tick as a vector of rickettsiae, data on their maintenance in various developmental stages of the arthropod as well as transmission to a host through feeding the blood are desirable. More attention should be focused to investigation on antibacterial (antirickettsial) effect of lysosyme, interferon and cellular elements in arthropods. Certainly mixed infections in ticks and namely their interactions, as well as the significance of rickettsia-like organisms in these arthropods, require also further investigations. Sufficient conclusive evidence concerning the effect of vector's organism on the biological properties of rickettsiae or in reverse, are almost unavailable. Investigations on above problems require the involvement of the modernest methods of immunology, immunochemistry, biochemistry and morphology.

Animals↗
PubMed1989

[Typhus infection (Brill's disease) in the environment of a large city].

The data on the epidemiological analysis of 675 cases of infection of the typhus nature, detected in Leningrad in 1974-1986, are presented. The seasonal morbidity curve, the age structure of patients, the character of the clinical course of the disease and other data gave a reason for the diagnosis of Brill's disease. The comparison of the relative data on morbidity rates in typhus at different periods of the current century was made.

Adolescent↗
PubMed1988

[An epidemiologic projection of foci of Q fever within herds].

In one of the rural regions of the nonchernozem zone retrospective epidemiological diagnosis was carried out in connection with high morbidity rates in acute respiratory diseases and influenza. This diagnosis was shown to cover cases of Q fever. Altogether 172 cases of this infection were retrospectively diagnosed. This infection affected persons working at one of sheep-breeding complexes, as well as at enterprises, technologically linked with this complex. Sheep proved to be the source of this infection, that was confirmed both serologically and by the registered cases of the isolation of Coxiella strain from sheep.

Agricultural Workers' Diseases↗
PubMed1988

[Characteristics of the interaction of Leptospira with the host organism in the infectious process in golden hamsters].

The comparative evaluation of the interaction of L. icterohaemorrhagiae strain P, L. canicola strain CL and L. hebdomadis strain 650 with golden hamster liver and kidney cells is presented. Three variants of the course of Leptospira infection have been distinguished: (1) the hepato-renal (icteric) variant, caused by the adhesion of leptospires to liver cells with the colonization of their surface and the disaggregation of liver-cell complexes and by the accumulation of leptospires in the kidney interstice; as a consequence, parenchymatous hepatitis and nephroso-nephritis develop, which lead to the death of animals; (2) the renal (anicteric) variant, characterized by the absence of the infective agent and lesions in the liver, by adhesion of leptospires to and their colonization of the nephrothelium of the proximal convoluted tubules of the kidneys; in this case some of the animals die because of renal insufficiency and shock, while in the surviving animals prolonged carrier state develops; (3) the intermediate variant, characterized by the initial process of leptospiral adhesion and colonization in the liver and its subsequent progress in the kidneys.

Animals↗
PubMed1987

[Interaction of Leptospira with the host's body in the infectious process in guinea pigs].

In experiments on guinea pigs the pathogenicity of leptospires is manifested by their adhesion to liver cells, colonization of the surface of these cells, accumulation of leptospires in the renal interstice and their colonization of the nephrothelial surface of proximal convoluted tubules in the kidneys, by toxic microcirculatory disturbances, dystrophy and necrosis of nephrothelial cells. Then the primary toxic action of circulating leptospires, microcirculatory disturbances and hemorrhagic syndrome augment during the colonization of the surface of liver cells, accompanied by their dystrophy and dissociation, as well as by jaundice. The accumulation of leptospires in the renal interstice and their subsequent multiplication on the nephrothelium of the proximal convoluted tubules are responsible for the development of interstitial nephritis and necrotic nephrosis. The persistence of lesions in the liver and kidneys, occurring in some cases in spite of elimination of the infective agent from these organs due to increasing antibody production suggests the toxic action of immune complexes.

Animals↗