SC-karyotyping on electronic microscopy (EM) analysis of synaptonemal complexes (SC) spermocytes of silver fox (Vulpes fulvus)

We present an electronic microscopy (EM) analysis of synaptonemal complexes (SC) spermatocytes of male silver fox Vulpes fulvus at the pachytene stage. The SC-karyotypes of pachetene cells were made and described. Knowledge of normal SC-karyotype is necessary to reveal synaptic abnormalities of autosome and sex bivalents during the pachytene. It was indicated that EM analysis of SC-spermatocytes—the study of synaptonemal complexes in agricultural animals—is a very good instrument for comparative analysis of normal SC-karyotype of foxes that carry chromosomal abnormalities and in fur-bearing animals as well.     

The dynamics of a local population of the Italian locust (calliptatus italicus l.) in an anthropogenic landscape

The dynamics of a local population of the Italian locust is characterized for an area near the northeastern boundary of its range. In this area, the situation during the Italian locust outbreak is quite different from patterns in dry steppes and semideserts (which are optimal territories for the species): hopper bands occupy small plots and migrate in short distances. This character of the dynamics is likely to be determined by sufficient food quantity and heterogeneity of local anthropogenic landscapes. As a result, the efficacy of the prospective technology for population management of locusts — barrier treatment — is extremely low.     

Regulatory disorders of locomotor functions in dogs during prolonged irradiation in a wide range of dose rates

A biphase pattern of the development of locomotor disturbances, connected with the primary response and cerebral radiation syndrome, was demonstrated in experiments with dogs subjected to prolonged irradiation, just as it was observed after acute exposure. Dose thresholds for the development of these states were somewhat higher with the prolonged irradiation. The time of the appearance of disturbances increased due to the delay of achievement the dose threshold increase with dose-rate decrease, the time interval needed for the development of the corresponding pathological process being unchanged. Due to the repair process the above syndromes were not manifested until the appropriate dose-rate thresholds were reached.     

Evidence for independent recruitment of zeta-crystallin/quinone reductase (CRYZ) as a crystallin in camelids and hystricomorph rodents

Zeta-crystallin/quinone reductase (CRYZ) is an NADPH oxidoreductase expressed at very high levels in the lenses of two groups of mammals: camelids and some hystricomorph rodents. It is also expressed at very low levels in all other species tested. Comparative analysis of the mechanisms mediating the high expression of this enzyme/crystallin in the lens of the Ilama (Lama guanacoe) and the guinea pig (Cavia porcellus) provided evidence for independent recruitment of this enzyme as a lens crystallin in both species and allowed us to elucidate for the first time the mechanism of lens recruitment of an enzyme- crystallin. The data presented here show that in both species such recruitment most likely occurred through the generation of new lens promoters from nonfunctional intron sequences by the accumulation of point mutations and/or small deletions and insertions. These results further support the idea that recruitment of CRYZ resulted from an adaptive process in which the high expression of CRYZ in the lens provides some selective advantage rather than from a purely neutral evolutionary process.      

Effect of cucumarioside (a triterpene glycoside from the holothurian Cucumaria japonica) on the development of an immune response in mice to corpuscular pertussis vaccine

The influence of cucumarioside, triterpene glycoside obtained from Cucumaria japonica (Echinodermata, Holoturioidea), or sea cucumbers, on the resistance of mice to Bordetella pertussis infection (with the use experimental pertussis meningoencephalitis as a model) and on the development of immune response to corpuscular pertussis vaccine was studied. The preparation under test was shown to have greatly pronounced immunomodulating properties depending on both the concentration of cucumarioside and the route of its administration, as well as on the dose of pertussis vaccine. When administered orally in a dose of 4 micrograms per mouse and intraperitoneally in doses of 0.04 and 0.0004 micrograms, cucumarioside enhanced the protective effect of corpuscular pertussis vaccine. The use of cucumarioside in a dose of 0.001 micrograms per mouse abolished the suppressive action of large doses of pertussis vaccine in the background rosette-formation test at an early period after immunization and increased number of immune rosettes formed by lymphocytes in the spleen of mice immunized with different doses of the corpuscular vaccine.     

Effects of extreme factors and antioxidant alpha-tocopherol on the intensity of blood plasma chemiluminescence]

It was established in experiments on rats that intensity of "fast flash" of iron-induced chemiluminescence of biological samples containing microvolumes of blood plasma correlate with resistance of organism to severe hypoxia. The new method is promising for the estimation of the sensitivity of intact organism to severe hypoxia, for registration of antioxidant therapy effects and for studying the mechanisms of extreme factors influence on the organism.     

Genetic determination of spontaneous and induced dominant lethality in Drosophila

Estimation of heritability ha2 index in experiments on spontaneous and induced dominant lethality gives the possibility to evaluate with sufficient accuracy genetic determination of the effect and its dependence on casual reasons. Besides, the individual breeding method gave quite stable data both on late embryonic lethality index and on heritability value. Directed selection of different test-objects (species or stocks of Drosophila) should be carried out using heritability index, since selection efficiency mostly depends on this value degree. Making stocks resistant and sensitive to certain mutagen classes, their comparison from the point of view of their pharmacogenetic features, on the basis of the indices used, may be taken as the start of studies aimed at further identification of certain biochemical factors or system taking part in manifestation of mutagenic effect. The data obtained permit us to suggest an idea of advisability of studying the genetic control of mutagenesis in humans using the method described.     

Electron microscopic study of the interaction between cytolytic T-lymphocytes and target cells]

Thymocytes stimulated in vitro in a mixed culture was sorbed by centrifugation on the surface of target cells for electron microscope study of cytology of immune T-lymphocytes and early cytolysis periods. A well developed Golgi apparatus was revealed in the cytoplasm of lymphocytes; there was also accumulation of tubular structures 50 to 60 nm in diameter which communicated with the cysterns of the granular endoplasmic reticulum, with "descended" vesiculi and plasmatic membrane of lymphocyte. This membrane formed numerous contacts with the membrane of target cells thus producing closed clefts. Taking into consideration these data and also current views on the intertransformation of membranes and intracellular transport a hypothetic scheme of the mechanism involved in the cytolysis of the target cell by immune T-lymphocyte was put forward.     

The effect of tryptophan, 5-hydroxytryptophan, serotonin, histidine and histamine on the peroxidation of lipids in hepatic mitochondrial membranes]

The method of recording the superweak chemifluorescence was applied to the study of the effect of tryptophan, 5-oxytryptophan, sertonin, histidine and histamine on the peroxication of lipids in the membranes of mitochondria of rat liver in the presence of Fe++ ions inducing this process. 5-oxytryptophan and serotonin inhibited this process in a concentration of 10(-5)-10(-4) M (protein content -1.8 mg per 1 ml of mitochondrial suspension). On the basis of studying the kinetics of the initial portion of the ascending branch of the "slow flare up" constants of the antioxidatinve activity (constituting 2.2-10(3) and 9.8-10(3) M-1 for 5-oxytryptophan and serotonin, respectively) was calculated. The antioxidative action is associated with the presence of the phenol group in the molecule of the compound under study. It is supposed that the action of 5-oxytryptophan and serotonin on peroxidation of lipids in the membranes was of significance for the regulation of permeability of the biological membranes, along with their effect on the other membrane processes.     

Mutations in PIP5K3 are associated with François-Neetens mouchetée fleck corneal dystrophy

Fran?ois-Neetens fleck corneal dystrophy (CFD) is a rare, autosomal dominant corneal dystrophy characterized by numerous small white flecks scattered in all layers of the stroma. Linkage analysis localized CFD to a 24-cM (18-Mb) interval of chromosome 2q35 flanked by D2S2289 and D2S126 and containing PIP5K3. PIP5K3 is a member of the phosphoinositide 3-kinase family and regulates the sorting and traffic of peripheral endosomes that contain lysosomally directed fluid phase cargo, by controlling the morphogenesis and function of multivesicular bodies. Sequencing analysis disclosed missense, frameshift, and/or protein-truncating mutations in 8 of 10 families with CFD that were studied, including 2256delA, 2274delCT, 2709C-->T (R851X), 3120C-->T (Q988X), IVS19-1G-->C, 3246G-->T (E1030X), 3270C-->T (R1038X), and 3466A-->G (K1103R). The histological and clinical characteristics of patients with CFD are consistent with biochemical studies of PIP5K3 that indicate a role in endosomal sorting.