The role of recipient cells in the mechanism of pathological calcification of heart valve transplants

It was found using the model of subcutaneous implantation in rats that the calcification of the aorta wall occurs by two mechanisms of which one is dependent on, and the other independent of the migration of recipient cells to the transplant.     

Finding of Molars of the Archaic Vole Lasiopodomys (Stenocranius) Gregaloides (Hinton, 1923) (Mammalia,Rodentia, Cricetidae) in the Late Pleistocene of the Southern Urals

Doklady Biological Sciences - A total of 1250 lower first molars (m1) of voles (Arvicolini) were studied from Late Pleistocene deposits (the radiocarbon dates from rodent bones: 17?100 ±...     

The use of the microdot immunoenzyme method for determining antibodies to Mycobacterium tuberculosis antigens

The microdot enzyme immunoassay (EIA) has been used for the determination of antibodies to M. tuberculosis protein fractions, crude antigenic preparations, PPD and old tuberculin in tuberculosis patients and healthy persons. Purified protein fractions have been found to possess the highest sensitivity and specificity in microdot EIA. The determination of antibodies to these fractions has permitted the differentiation of persons infected with M. tuberculosis from healthy ones. The use of M. tuberculosis protein fractions permits the determination of IgA and IgC in the sera of tuberculosis patients.     

The problem of enhancing the biological action of ionizing radiations. Glucose as an agent for increasing the radiosensitivity of Ehrlich ascitic carcinoma cells in vitro

The effect of short-term incubation of Ehrlich ascites tumor cells in a medium containing excess glucose on their radiosensitivity was studied with a reference to the growth of tumors of ascitic and solid forms. It was shown that the incubation of cells with glucose, being accompanied by a change in pH of the suspension, caused, by itself, only a slight increase in the duration of the latent period of solid tumor formation and in the life-span of mice with ascitic tumors but increased considerably the lethal effect of radiation, as was estimated by the above mentioned criteria and the percentage of inoculated tumors.     

Immune response of CBA mice in postnatal ontogeny

Changes in the pattern of immune response of the CBA mice during postnatal ontogenesis were studied on the models of cellular and humoral immunity. The functions mediated by the amplifier cells were shown to undergo the most significant changes. This was confirmed by a decrease in the activity of antigen-nonspecific T-suppressors, as estimated in a semisyngeneic system, an increase in the capacity of spleen lymphoid cells to induce the "graft versus host" reaction with the age and preservation of the function of hypersensitivity effectors of delayed type at the same level (after the age of 3-4 months). It is suggested that these changes might cause an age decrease in the suppressor activity of T-cells in a response to insoluble antigens.     

Genetic heterogeneity of Borrelia afzelii in the natural focus of the Middle Urals

As shown by sequencing the spacer rrf (5S)--rrl (23S) in 72 isolates of B. afzelii (one of the causative agents of Ixodes tick borne Borrelia infections) and the chromosomal gene coding protein P66 in 22 isolates, that in the natural focus located in the Middle Urals two different genetic subgroups (VS461 and NT28) of this genospecies simultaneously circulate. These subgroups are represented by 5 gene variants (rrf) 5S--(rrl) 23S and 5 allelic variants in gene p66. The latter, similarly to spacer gene variants, are not linked with a definite host and occur in different rrf--rrl variants of the infective agent. At the same time the definite species of vectors and carriers may be the host of several different B. afzelii variants, both in the spacer and in the gene coding protein P66, which maintains the genetic heterogeneity of B. afzelii population in the natural focus.