Consumption of aquatic subsidies by soil invertebrates in coastal ecosystems

Routes of aquatic allochthonous inputs (aquatic subsidies) to detrital food webs are studied, as is the effect of aquatic subsidies on the functional and taxonomic structure of soil invertebrate communities in coastal ecosystems. The study took place in the coastal zone of an oxbow lake of the Pra River in the Oka Reserve. The results indicate a strong dependence of soil animals in the coastal habitats on aquatic subsidies. Isotopic analysis shows that aquatic resources enter soil food webs not only via predators feeding on flying insects or aquatic prey, but also via saprophages decomposing organic debris of aquatic origin. The contribution of aquatic subsidies to the energy balance of soil invertebrates decreases rapidly with increasing distance from the lake. The fraction of aquatic carbon in tissues of collembolans and saprophages is negligible already a few meters from the water edge. The dependence of predatory invertebrates on aquatic resources can be traced at somewhat greater distance (tens of meters).     

A new role for PGRP-S (Tag7) in immune defense: lymphocyte migration is induced by a chemoattractant complex of Tag7 with Mts1

PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4⁺ and CD8⁺ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.     

A possibility to predict the severity of individual damage following the exposure to supralethal radiation dosage. Prediction by early radiation response

The experiments on dogs and monkeys have shown that the severity of radiation sickness following the exposure to supralethal radiation doses can be predicted by early response of an individual. For such prediction, the most informative criteria include general severity of clinical manifestations during primary radiation response and evaluated within a few post-damage hours, the degree of tension in cardiac rhythm control, the cortisol level, the endocrine status index.     

Quantitative regularities for clinical manifestations of radiation injury in large-sized laboratory animals exposed to supralethal radiation doses Gamma-neutron and electron biological effectiveness as influenced by exposure conditions and dose distribution in the animal body

The damaging effect of gamma-neutron radiation over a wide neutron-energy range, with average values of 0.37 and 1.2 MeV, and that of electrons with an average electron energy of 25 MeV have been compared in dogs and two monkey species exposed to a broad range of supralethal doses. An analysis of absorbed dose distribution in critical organs and systems has shown the highest effect of gamma-neutron radiation with an average neutron energy of 1.2 MeV. With severity of early clinical manifestations of damage as a criterion, electrons have appeared the most effective. The radiosensitivity of animals grew in the order as follows: dog-->M. fascicularis-->P. hamadryas.     

Statistical analysis of the distribution of the antibody levels to Mycobacterium bovis antigenes for bovine tuberculosis diagnostics

The antibody responses to the recombinant analogs of Mycobacterium bovis antigens rMPB63 and rMPB83, as well as to tuberculin PPD, were determined in 96 bovine blood serum specimens. A statistical approach based on the approximation with multiple Gaussian curves with Levenberg-Marquardt algorithm was proposed for analysis of the distribution of antibody levels to the studied antigens. The results demonstrate that the recombinant MPB63 and MPB83 antigens along with the traditionally used PPD are appropriate for designing the test kits for diagnosing bovine tuberculosis at a herd level.     

Morphological abnormalities among the offspring of irradiated pines (pinus sylvestris L.) from chernobyl populations

The significant changes of the quantitative signs and the increase in the frequency of morphological abnormalities were found among the offspring of pines (Pinus sylvestris L.) exposed as a result of the Chernobyl accident. We have detected that the typical effects of radiation exposure (stimulation, inhibition, abnormalities of morphogenesis) are transmitted to the offspring of irradiated pine trees. The mechanisms of their occurrence are discussed.     

Interaction of diphtheria toxin B subunit with sensitive and insensitive mammalian cells

The recombinant fluorescent derivative of diphtheria toxin (EGFP-SbB) obtained by the replacement of toxin A subunit by enhanced green fluorescent protein (EGFP) has been used for visualization of the interaction of diphtheria toxin (DT) with sensitive and insensitive cells. It was shown that EGFP-SbB could interact with cell surface of both toxin-sensitive monkey cells (Vero cell line) and toxin-resistant mouse cells (3T3 cell line). The affinity of this protein for receptors of Vero cells was three times higher as compared with 3T3 cells. It was demonstrated that fluorescent derivate was able to interact with receptors of both cell lines and to internalize into these cells. Internalization of EGFP-SbB into the cells was inhibited by endocytosis inhibitor phenyl arsine oxide. We suppose that diverse sensitivity to DT of monkey and mouse cells can be explained not only by differences in their receptor affinity for DT but also by the processes that occur after internalization of the toxin into the cells.     

Reaction of the blood forming system of the dogs to acute radiation exposure (by the SRC-Institute of biophysics data bank)

At present time in the SRC--Institute of Biophysics the data bank containing the information on the reactions of 431 dogs to radiation exposure in a wide range of doses has been created. By the results of 4299 blood tests reporting a leukocyte content, including 2509 tests reporting a blood formula, the individual peculiarity of the peripheral blood reaction in dogs were analyzed. Dose dependencies for the reaction of blood-forming system to radiation exposure to doses in the range from 1.0 to 7.0 Gy were obtained. In comparison with the similar data for humans, the neutrophil content in peripheral blood decreased approximately 1.5-2.0 times faster in dogs than in men, resulting in earlier recovery.