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Background Rhinonyssid mites are permanent parasites of birds that inhabit their respiratory tract. There are around 600 species described worldwide and almost all species of birds are found to have embedded rhinonyssid mites. Despite their presumed relevance, these mites are largely unstudied due to the difficulty in sampling them and, therefore, the majority of mite-host associations and species-prevalence data are unknown. New information In this study, 179 mite specimens belonging to 27 species and eight genera were identified. Notably, 18 new mite-bird associations were documented for the first time, thus increasing the known host range for these mite species. In addition, mite-host associations found in this study were compared with known associations from these species of birds in the European part of Russia and in Europe. Overall, this study represents the largest survey to date carried out on rhinonyssid mites in Russia and one of the most comprehensive datasets on rhinonyssid host-range. [ABSTRACT FROM AUTHOR]

Design calculations of the modulus of deformation of non-dilatant argillaceous (clay) soil based on the theoretical solution for a head resistance of a sounding device are presented. The results of calculations for the data of static sounding are compared with those taken as standards of the Russian Federation; a completely satisfactory correspondence is shown. [ABSTRACT FROM AUTHOR]

The studying Rhinonyssid taxonomy is engaged many researchers all over the world. Russia is a place for much of the published research on the nasal mites. But Leningrad region was not investigated yet. The present note is based on 21 weeks intensive field collecting in Leningrad province. For the period March-July 2010 in the Leningrad province were studied 671 specimens, which relate to 23 species, 18 genera, 13 families, 5 orders. 85 specimens (13%) out of all examined birds were parasitized by Rhinonyssidae. Parasite mites belong to the genera Ptilonyssus and genera Tinaminyssus. [ABSTRACT FROM AUTHOR]

The article discusses a study of the relationship between chronic exposure to ionizing radiation (IR) and hematopoiesis reduction. Data used were gathered from the hemograms of 3,200 Techa, Russia riverside villagers from 1951-1956, during which time exposure to IR gradually decreased. Results show increased frequency of cytopenia with higher dose rates and hematopoiesis reduction patterns that were more affected by exposure than age and health.

The article presents a human hematopoietic system model which allows estimation of hematopoiesis inhibition and increased risk of late stochastic effects arising from exposure to ionizing radiation (IR). It references data from blood counts performed between 1950 and 1956 on 3,500 Techa, Russia riverside residents. It is noted that the model may be used to predict early effects of chronic exposure to IR and to estimate late stochastic effects.

The article discusses a study on the effects of chronic radiation exposure due to 90Strontium (Sr) on the hemopoietic system and bone tissue state of Techa riverside residents in Russia exposed to radioactive waste discharges from 1950 to 1956. The key information source used in the study was the Urals Research Center for Radiation Medicine (URCRM) database. During the first decade after exposure, leukocyte counts of residents were significantly reduced. Age reportedly influenced the bone mineral density for the residents.

A biologically motivated dynamical model of the lymphocytopoietic system in irradiated humans is applied here to analyze the data obtained under hematological examinations of residents of Techa riverside villages. Those people were exposed to chronic irradiation with varying dose rates, due to the radioactive contamination of the river basin by the Mayak Production Association. Modeling studies revealed the relationship between the dynamics of the lymphocytopoietic system in the examined individuals and the variation of dose rate over the considered period of time. It is found that the developed model is capable of reproducing the decreased level of blood lymphocyte concentration observed during the period of maximum radiation exposure, the recovery processes in the system observed during the period of decreasing dose rate, as well as the enhanced mitotic activity of bone marrow precursor cells in this hematopoietic lineage observed during the entire period under consideration. Mechanisms of these effects of chronic irradiation on the human lymphocytopoietic system are elucidated based on the applied model. The results obtained demonstrate the efficiency of the developed model in the analysis, investigation, and prediction of effects of chronic irradiation with varying dose rate on the human lymphocytopoietic system. In particular, the developed model can be used for predicting any radiation injury of this vital system in people exposed to chronic irradiation due to environmental radiological events, such as anthropogenic radiation accidents or radiological terroristic attacks.

A profound approach to the analysis of clinical data on the dynamics of major hematopoietic lineages (granulocytopoietic, thrombocytopoietic, and erythrocytopoietic systems) in chronically irradiated humans is proposed. It is based on recently developed mathematical models of these systems in humans, which enable one to study and interpret clinical hematological data. The developed approach is applied to the analysis of statistically processed clinical data, which were obtained under hematological examinations of residents of Techa riverside villages. These people were exposed to chronic irradiation with varying dose rate due to the radioactive contamination of the river basin by the Mayak Production Association. In the course of modeling studies, the relationship between the dynamics of aforementioned systems in examined individuals and the variation of chronic exposure dose rate over the considered period of time is revealed. It is found that the models are capable of reproducing common regularities and peculiarities of the dynamics of systems on hand, including the decreased stationary levels of blood cell concentrations during the period of maximum radiation exposure, the recovery processes during the period of decrease of exposure dose rate, and the prevalence of younger bone marrow granulocytopoietic cells over more mature ones during the entire period. The mechanisms of such effects of chronic irradiation on the hematopoietic lineages are revealed on the basis of modeling studies. All this testifies to the efficiency of employment of the developed models in the analysis, investigation, and prediction of effects of chronic irradiation on human hematopoietic system.

Scientific (analytical) approach directs researcher to the study of nosology in isolated native view. The phenomenon under consideration- comorbidity becomes significant and to a substantial degree is able to affect all aspects of the process of medical care. This is shown in this review along such directions as frequency of overt or concealed comorbidity or real state of the problem; magnitude of intracardiac and extracardiac comorbidity; difficulties of diagnostics and treatment arising with comorbidity; problems of validity of statistical (and epidemiological) side of the matter; value of social and organizational aspects of patients care in situations when comorbidity is present.

The purpose of this study is a retrospective estimation of the influence of dose and dose rate of the red bone marrow chronic radiation exposure in combination with various modifying factors (gender, age, comorbidity) on the frequency of deviations from normal values of the results of peripheral blood investigation in humans exposed on the Techa River. The results of investigation show that humans chronically exposed to radiation can develop marked changes in the cellular composition of peripheral blood characterized by a tendency to cytopenia (signs of the decompensation of hemopoiesis). The tendency to cytopenia can be identified earlier in the lymphoid germ, and later in platelet and erythroid lines. A high lability of granulocytes under the influence of various, often infectious, factors is the cause of the lack of statistically significant differences in terms of frequency of neutropenia. Several non-radiation factors (gender, age, health status) in combination with radiation exposure could have a modifying influence on hematopoiesis, which contributed to the disruption of adaptation processes and the development of conditions characterized by a tendency to cytopenias in exposed individuals. The red bone marrow dose rate reduction resulted in a gradual decrease in the frequency of erythrocytopenia, thrombocytopenia, neutropenia and lymphocytopenia in the group of exposed population. Increased frequencies of erythrocytosis, thrombocytosis, lymphocytosis, monocytosis and neutrophilia were observed when the median dose rate was reduced to the level of 0.024 Gy/year (in the year 1956), which could be regarded as activation of regenerative processes in hematopoiesis.

Residents of the Techa riverside villages chronically exposed to ionizing radiation (the average dose rate in 1951-1956 was 0.047 Gy/year, the maximum reached 2.44 Gy/year) developed marked changes in the cellular composition of peripheral blood. The maximum reduction of peripheral blood counts occurred in the years 1951-1953, after which the beginning of the restoration of cellularity to the control level was observed. The dose rate at this point (1956) was about 0.02 Gy/year. The factors of radiation and non-radiation nature (gender, the age at the onset of exposure, health related disorders) in different combinations affect the number of peripheral blood cells. The influence of dose rate of a chronic radiation exposure on a platelet count takes precedence over other factors. The factors of gender and dose rate determine the number of erythrocytes in exposed persons. The changes accompanying the health status and dose rate significantly affect the number of neutrophils. The influence of comorbidity, age and dose rate on the number of monocytes was noted. A lymphocyte count was mainly determined by the age at the onset of exposure and concomitant diseases. A joint influence of chronic radiation exposure and concomitant diseases increases a mutual action on erythro- and thrombocytopoiesis. The decrease of the dose rate was followed by a gradual predominance of the somatic disease influence on leukocyte (neutrophils, lymphocytes and monocytes) counts.

Unlabelled: The present paper focuses on the analysis of data resulting from 50-y studies involving assessment of the hemopoiesis state in Techa riverside residents chronically exposed to radiation and evaluation of the bone tissue status for people with Sr incorporation at late time after the intakes., Conclusions: 1. In the late period after the start of chronic radiation exposure (50 y later) only a few individuals with red bone marrow doses reaching about 1.8 Gy (mean dose of 0.66 Gy) had a marked peripheral blood leucopenia, and the incidence of neutropenia, lymphopenia and thrombocypenia in the exposed group did not exceed that noted in the control group. The results of our observations indicate the spontaneous recovery of the hemopoietic system of residents of the Techa riverside villages. Thus, the adaptation mechanisms of hemopoiesis to the long-term chronic exposure in the range of low to intermediate doses are sufficiently effective; 2. About half of the people with Sr incorporation and the control group have changes in bone tissue expressed by different stages of osteoporosis. Age is a determinative factor of bone tissue involution in women while some tendency of Sr influence on the intensity of osteoporosis is revealed in the male group.

As the result of the study of Caspian seals, the presence of antibodies to Brucella was detected in the blood serum of these animals. The annual dynamics of the proportion of seropositive animals was noted. These data indicate the possibility of the circulation of the infective agent of brucellosis in the population of Caspian seals.

The paper is concerned with the results of a special study of the deontological potential of students prior to and after subinternship. Their attitude to occupation, the knowledge of the fundamentals of deontology, motivation of behavior in specific deontological situations and the reasoning of their actions and opinions were determined. A considerable gap between a high level of correct theoretical (declarative) ideas of deontology rules and inability to use them in everyday clinical practice was observed. Experience of the correction of graduates' deontological disposition was presented. The dialectic unity of inductive and deductive methods in mastering the fundamentals of deontology was stressed. Methods of the verification of deontological training of students in medical institutes were specified.