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Biomedical subjects

A Ia Lysenko

Publications and source records attributed to A Ia Lysenko.

At least 73 records · Page 4Linked to original sources

[The host-opportunistic protozoon system. The manifestation of Leishmania infantum infection in naturally resistant adult white rats subjected to drug immunosuppression].

The attempt to overcome the natural resistance of white rats Wistar to Leishmania infantum infection was made by the mean of the immunodepressant Tricort-40, the corticosteroid of prolonged activity. In the series of experiments with the mercy scheme of immunosuppression the inoculation of the amastigotes L. infantum taken out of the donors, the golden hamsters Mesocricetus auratus, caused the progressive infection with intensive affection on target organs (the spleen, liver, bone marrow). The stem of L. infantum been passed through the immunosuppressed rats has preserved its pathogenicity to the golden hamsters.

Animals↗

[The role of opportunistic protozoa in human pathology today].

The paper deals with opportunistic protozoa, their common properties distinctions from commensals and obligate parasites, and the specific features of their caused opportunistic infections. It also provides evidence for the increasing contribution of opportunistic protozoa to human pathology today and for paramount necessity for researchers and practitioners of various disciplines to lay a special emphasis on them.

AIDS-Related Opportunistic Infections↗

[Approaches to assessing the parasitological profile of Russia. 1. Study of the method of quantifying].

The technique may be effectively used in assessing the territory of the Russian Federation for human parasitic diseases (some parasitic entities, their complexes, economic damage caused by parasitoses, etc.) on the basis of official statistics. The aggregability levels will greatly vary with the nature of the baseline values while cartographically describing the parasitism situation in an area. The best results are obtained while estimating the absolute number of the notified parasitic cases, rather the morbidity rates calculated per 100,00 population. The areas including 2 first quartiles (i.e. the most high density) concomitantly for 6, 5, 4, etc. parasitoses while assessing the parasitic situation. The areas where the parasitic diseases under study are recorded, but which have no infestation rates that form the first 2 quartiles (i.e. that are characterized by a comparatively low density for the whole analyzed parasitic complex) remain burden-free.

Disease Reservoirs↗

[The host-opportunistic protozoa system. The dissemination of Leishmania infantum infection in naturally susceptible laboratory animals subjected to drug-induced immunosuppression].

The possibility to awake the disseminated infection of Leishmania infantum in golden hamsters Mesocricetus auratus, hispid cotton rats Sigmodon hispidus, soft furred rats Mastomys natalensis by means of different immunodepressants has been examined. On the background of the immunosuppression caused by corticosteroids of short time activity (metipred, hydrocortison) leishmaniae were revealed both in the target organs (spleen, liver, marrow) and in lungs, in cases of using the corticosteroid of prolonged activity (tricort-40) leishmaniae were observed also in lungs, kidneys, testis.

Animals↗

[The host-opportunistic protozoa system. The dissemination of Pneumocystis infection in white rats under the influence of drug-induced and biological immunosuppression].

The main purpose of the present study is the investigation of relationships of Pneumocystis carinii with the organism of white rat Wistar, which is natural carrier of this parasite. The series of experiments has shown that the immunosuppressor Tricort-40 (corticosteroid of prolonged activity) in a short time reactivates the Pneumocystis infection. The parasites have been observed in a great number in the lungs and rarely in the liver. The reactivation and dissemination of the Pneumocystis infection have been achieved constantly and with great expression by the combined immunosuppression of rats, by the medicamentous immunosuppression (injection of T-40) and biological one (infection with amastigotes Leishmania infantum). The developing mixed-infection (with pneumocysts and leishmania) could be the basis for the parasitocenological relationships.

AIDS-Related Opportunistic Infections↗

[How many patients with visceral toxocariasis in Russia?].

Based on the results of numerous seroepidemiological surveys of inhabitants in Russia using the Toxocara/IgG enzyme immune test system and supposing that extremely high antibody titers (1:6400 or higher) are an indicator of manifest visceral toxocariasis, the possible number of patients with this infection was estimated in the Russian Federation. The absolute number of the patients is roughly 550,000, the relative rate is 380 per 100,000 population. Children aged 0-9 years were shown to prevail among patients with visceral toxocariasis; among the children, boys are predominant. The paper also provides the percentage of seropositive individuals in various in various foci of Russia and its adjacent states (among the 21,233 inhabitants under study, the mean rate is 6.8% ranging from 0 to 21.5%). Groups at risk for Toxocara canis infection include veterinarians, automobile drivers and fitters, scavengers, among whom the number of seropositive individuals is substantially higher than that in the control group of inhabitants.

Adolescent↗

[The prevalence of cryptosporidiosis among the city population of Russia and Belarus].

A total of 248 adults (170 with somatic diseases and 78 with the diarrheal syndrome) and 1206 children (323 attending kindergartens, 231 with somatic diseases, and 652 with the diarrheal syndrome), residents of seven towns of Russia and Belarus, were examined for cryptosporidiosis in 1989-1992. The mean infection rate of children and adults with the diarrheal syndrome was 4.8 and 2.7%, respectively, of those with somatic diseases 2.6 and 0% respectively, and of healthy children 1.9%. Children living in the towns of Belarus, localized in the radiation contamination zone, were more frequently infected than children living in other towns. The towns of the European Russia and Belarus should be regarded as stable foci of cryptosporidiosis infection.

Adolescent↗

[The development of a new experimental model of pneumocystosis].

The corticosteroid tricort-40 (triamcinolone acetonide) was found to induce the reactivation of endogenous pneumocystic injection caused by P. carinii in Wistar rats given 5-9 infections subcutaneously in median doses of 0.5-4.0 mg/kg at 6-22 days intervals each. Manifest P. carinii infection in the animals was characterized by early detection of its agent (starting from week 2 of immunosuppression), a progression of the infection and its transition to the generalized stage. The combined use of tricort-40 and infection of the animals with Leishmania infantum as an immunosuppressive cofactor ensured an increase in reproducibility of a manifest pneumocystosis model and its more rapid transition to the generalized stage. The experimental model of mixed infection of two AIDS-associated parasite infections--generalized pneumocystosis and visceral leishmaniasis--was first reproduced in inbred rats, which may be suitable for simultaneous screening of new antipneumocystic and antileishmanial drugs.

Animals↗

[The host-opportunistic protozoa system. The outcome of a Leishmania infantum infection in white rat pups naturally resistant to Leishmania infection].

It was found out, that non-lineal young white rats have a natural resistance to the leishmania infection, but it could be overcome with the mean of immunosuppression caused by the corticosteroid of prolonged action Tricort-40. The leishmania infection caused by immunosuppression is successfully eliminated by the animal organism soon after the stopping of immunosuppressant action, that could be considered as the restitution of the natural resistance.

Aging↗

[The host-opportunistic protozoa system. The effect of ionizing radiation on the prevalence of cryptosporidiosis and pneumocystosis].

The aim of this study was to determine an influence of ionized radiation on the prevalence of Cryptosporidium and Pneumocystis carinii (P. c.) infections in children inhabitants of settlements affected by radionuclides after Chernobyl accident. Survey of children from day-care centers for prevalence of Cryptosporidium was carried out in Bryansk region, Russia, and Gomel and Mogilev regions, Belarus; children from cities Mogilev and Gomel as well as small town Pochep, Bryansk region, serve as control clean zones. Survey for P. c. seroprevalence was carried out in town Novozybkov, Bryansk region, Specific Ab to P. c. determined by "Pneumo-test" system (Nyarmedic. Moscow. Russia), an evaluation of immune status included assessment of Ig in serum and saliva by Manchini method. Results of the study were as follows: 1) of 432 healthy children surveyed for Cryptosporidium oocysts 352 were from affected regions: the prevalence in Bryansk region was 8% vs. 2.8% in control, in Gomel and Mogilev 4.1% vs. 2.8%. 2) Prevalence anti-P.c. Ab accounts 56.3% in children and 78.2% in adult inhabitants of Novozybkov vs. 30% in children of control group. Special interest presents an relationship of seroprevalence P.c. and secretory immunity examined twice with 2 month interval. At the first survey IgG in seropositive for P. c. children was found in 36.8% (vs. 23.1% in control) and secretary IgA in 13.2% vs. 5.8% in control. At the second survey IgG was found in 53.4% vs. 21.8% and IgA in 2.7% vs. 1.8% in control. Taking into consideration the known fact that IgG and IgA in saliva are result of their transudation from blood through the inflammatory mucosa we consider that long ionized radiation impairs the barrier function of mucosae.

Adult↗

[The host-opportunistic protozoa system. The incidence of mixed infections (Pneumocystis and cytomegalovirus) in children living in radionuclide-contaminated areas].

The purpose of our study was to determine the influence of ionized radiation onto the frequency of mixed infections (P. carinii and Cytomegalovirus) in children inhabitants of the settlements affected with radionuclide after Chernobyl accident. Two groups of children were under survey. 1) 103 inhabitants of Novozybkov (Bryansk Province, Russia) and 38 patients under observation in Moscow paediatric hospital from another affected villages (5-15 Ci/km2) were examined serologically by the diagnostic system "Pneumo-test" and "Cytomegatest" (Nyarmedic, Moscow, Russia). Cut-off titers for P. carinii were IgM-1: 200, IgG-1: 20, for CMV IgG-1: 200, 2) Retrospective study of 563 patients with respiratory pathology and 1809 died children after acute pneumonia during 14 years period. Sputum and mucus of the patients taken by laryngoscopy and bronchoscopy were studied for P. carinii by microscopy, the section of lungs--histologically. The sediments of urine and saliva were examined for CMV by microscopy and section of different organs_-histologically. Examinations were performed by one and the same highly qualified pathologist. The results of the study were as follows. 1. Of 563 children examined for both P. carinii and CMV 186 (33%) were positive for P. carinii and 189 (33.7%) for CMV. Both pathogens were found in 46 children (8.2%), mainly among 1-2 and 6-12 month age (8.5 and 14.5%, respectively). Retrospective analysis of 1809 autopsy results shows, that in 73 cases (4%) were found only P. carinii, in 200 (11.1%) only CMV and in 24 (1.3%) two pathogens simultaneously. 2. Of 103 children surveyed serologically P. carinii monoinfection was found in 7 (8.8%), CMV-in 25 (24.3%) and coinfection in 55 (53.4%). Estimated frequency for coinfection (if combination of two infections were to be accidental) should equal 46.8%. In control group consisted of 30 children from clean Moscow region the rate of coinfection was 16.7% and estimated rate 15% (the difference between empiric and estimated rates are statistically significant, t > 4). Thus it is clear that the rate of coinfection of P. carinii and CMV is always high either in clean or in affected by ionized radiation regions. This rate determined by microscopy was higher in patients (8.2%) than in autopsy cases (1.3%) and much higher in children from affected region (53.3%) than in control (16.7%), being determined serologically. Separate interest present geometric mean titers found in the cases of coinfection. The titer for anti-CMV IgG in children from affected regions was rather high (5884 vs. 1246 in control) and on the contrary titers for anti-P. carinii IgM and IgG were lower than in control (512 vs. 1245 and 58 vs. 159 respectively). We are incline to interpret the results of our study as evidence of increased susceptibility to P. carinii and CMV in those children whose immune system was suppressed by premorbid factors or ionized radiation and peculiar symbiotic relationships of P. carinii and CMV resulting in enhancement of their infectiousness.

Autopsy↗