Effect of thymalin on the function of the blood kallikrein-kinin system in thymectomized rats

The effects of thymus ablation and injection of thymalin on the blood plasma kallikrein-kinin system were studied. Thymus ablation was followed by activation of kinin formation, evidenced by an elevation of the total kallikrein activity and drop of the kininogen level. Injection of thymalin into thymectomized animals makes the characteristics under study return to normal.     

Effect of substances of a polypeptide nature isolated from the cerebral cortex on the immune response of mice

The influence of low molecular weight polypeptides (Mol wt below 10,000) isolated by acetic acid extraction from the cortex and white matter of the brain and from the bone marrow of cows on the primary immune response to SRBC was studied in experiments on 248 male CBA mice. The results showed that after the subcutaneous injections of the preparations from the cortex (where the theta-antigen cross-reacting with the thymocytes was localized) for 5 days prior to and 3 days post immunization, hemagglutinin titres and the quantity of direct (IgM) and indirect (IgG) antibody-forming cells increased 2.5 times in comparison with the control. The preparations from the white matter of the brain and from the bone marrow failed to demonstrate such an effect.     

Identification, purification and physico-chemical properties of neurospecific alpha 1-globulin]

The partially purified and concentrated 500-600-folds protein fraction has been obtained from human brain extract. This protein fraction was used for the immunization of rabbits. The corresponding anti-sera have the potency to detect the brain specific alpha 1-globulin, which is not identical to known cytoplasmatic brain specific protein. These antisera were used for the control of the antigen purification procedure which included ion-exchange, affinity and hydropho'ic chromatography, gel-filtration and isochromatofocusing. The antigen, purified to the homogeneity, has the electrophoretic mobility of the alpha 1-globulins, M(r) = 110-10 kD, and isoelectric point at pH 2.9-3.1.     

Causes of Technogenic Changes in a Freshwater Zooplanktonic Community

The situation in water bodies of northwestern Karelia in 1992–2001 was analyzed. As a result of waste discharge from the mining and ore-processing works, weakly mineralized hydrocarbonate-calcium waters changed into highly mineralized waters with the prevalence of potassium ions and sulfates. The total abundance and biomass of zooplanktonic communities decreased. Using the methods of principal components and partial correlations, differences in the responses of zooplankters to mineral pollution were revealed. Typical inhabitants of northern water bodies decreased in numbers, and the species Eudiaptomus gracilis Sars and Heterocope appendiculata Sars (Calanoida) disappeared. On the other hand, eurybiontic species prevailing in water bodies with higher mineralization manifested a positive reaction to the increase in the contents of dissolved mineral compounds. Toxicological experiments made it possible to estimate the survival threshold for E. gracilis and H. appendiculata: the populations of these crustaceans in the polluted water body perished when potassium concentration in water exceeded 50 mg/l.     

On the biology of the bird parasite <Emphasis Type="Italic">Neottiophilum praeustum</Emphasis> (Meigen, 1826) (Diptera,Neottiophilidae)

The first data on blood-sucking ectoparasitic larvae of Neottiophilum praeustum (Meig.) which develop in bird nests are presented in Russia, with the fieldfare Turdus pilaris L. as a host example. Larval development takes not more than 10–12 days but no puparia are formed until late autumn. The larvae of Neottiophilum resemble those of calliphorid flies both in body structure and life mode. The main diagnostic characters of Neottiophilum larvae distinguishing them from calliphorid ones are the spiracular disk of the posterior spiracles being positioned dorsal rather than ventral to the stigmal plate and lying outside rather than inside its peritreme. In addition, the anterior spiracles have 14–15, rather than 3–8 spiracular chambers.     

Analysis of <Emphasis Type="Italic">GJB6</Emphasis> (Сx30) and <Emphasis Type="Italic">GJB3</Emphasis> (Сx31) genes in deaf patients with monoallelic mutations in <Emphasis Type="Italic">GJB2</Emphasis> (Сx26) gene in the Sakha Republic (Yakutia)

Тhe DNA testing of autosomal recessive deafness type 1A (DFNB1A, MIM 220290) is complicated when deaf patients have only monoallelic (heterozygous) recessive mutations in the GJB2 (Сх26) gene that is uninformative for establishment of diagnosis. Such patients may be “random” heterozygous carriers of GJB2 mutations as well as have the mutant allele in a cis-regulatory region of GJB2 gene, in element genes encoding other connexins: GJB6 (Сх30) or GJB3 (Сх31). Previous studies of genetic causes of hearing loss in patients from Yakutia were directed to search for only mutations in the GJB2 gene, and the DNA diagnostics was uninformative for 9.7% (38/393) of the patients with monoallelic GJB2 mutations. In this work the search for mutations in genes GJB3 and GJB6 and two deletions с.del(GJB6-D13S1830) and с.del(GJB6-D13S1854) to the cis-regulatory region of GJB2 gene was conducted in 35 patients with GJB2 monoallelic mutations and in 104 normal hearing individuals. The genes studied are two synonymous substitution c.489G>A (р.Leu163Leu) (GJB6) and c.357C>T (р.Asn119Asn) (GJB3) have been found, probably do not have clinical significance, and two nonsynonymous substitution c.301G>A (p.Glu101Lys) (GJB6) and с.580G>A (p.Ala194Thr) (GJB3). Additional experimental evidences are needed for confirmation of pathogenic significance of detected nonsynonymous substitutions in development of hearing loss in studied patients. Diagnosis of the DFNB1A was confirmed in only one patient, who was discovered by the deletion с.del(GJB6-D13S1830) (GJB2) in combination with a recessive mutation с.35delG (GJB2). In general, our results indicate low contribution of mutations in genes GJB6 and GJB3 in hearing loss etiology in Yakutia.     

Protective systems of immunocompetent organs in fishes from different ecological and systematic groups

This article presents the results of analysis of parameters of the immune, antioxidant, and monooxygenase systems in the immunocompetent organs (pro- and mesonephros, spleen, and liver) of species belonging to different systematic and ecological groups, namely, northern pike Esox lucius, zander Sander lucioperca, and bream Abramis brama. Although having the same features in the functioning of homeostatic mechanisms in the species under study, significant differences were revealed between bream and another two species with respect to the parameters of the nonspecific immunity of tissues and enzyme systems that perform protective functions. In all the three species, the basic role in processes of immunopoesis and nonspecific protection is played by the kidneys and spleen, while the greatest values of the parameters of antioxidant defenses and ethoxyresorufin-O-deethylase activity were recorded in the liver.     

A seriation approach for visualization-driven discovery of co-expression patterns in Serial Analysis of Gene Expression (SAGE) data

Background

Serial Analysis of Gene Expression (SAGE) is a DNA sequencing-based method for large-scale gene expression profiling that provides an alternative to microarray analysis. Most analyses of SAGE data aimed at identifying co-expressed genes have been accomplished using various versions of clustering approaches that often result in a number of false positives.

Principal Findings

Here we explore the use of seriation, a statistical approach for ordering sets of objects based on their similarity, for large-scale expression pattern discovery in SAGE data. For this specific task we implement a seriation heuristic we term ‘progressive construction of contigs’ that constructs local chains of related elements by sequentially rearranging margins of the correlation matrix. We apply the heuristic to the analysis of simulated and experimental SAGE data and compare our results to those obtained with a clustering algorithm developed specifically for SAGE data. We show using simulations that the performance of seriation compares favorably to that of the clustering algorithm on noisy SAGE data.

Conclusions

We explore the use of a seriation approach for visualization-based pattern discovery in SAGE data. Using both simulations and experimental data, we demonstrate that seriation is able to identify groups of co-expressed genes more accurately than a clustering algorithm developed specifically for SAGE data. Our results suggest that seriation is a useful method for the analysis of gene expression data whose applicability should be further pursued.     

Global characteristics of an ATON stationary plasma thruster operating with krypton and xenon

The global characteristics of an ATON stationary plasma thruster operating on xenon and krypton are investigated. It is shown that, with krypton, the thrust at the same mass flow rate of the working gas is greater and the efficiency is somewhat lower than those with xenon. An efficiency of ～60% was achieved with krypton for the specific impulse attaining 3000 s. The jet divergence is ～±22° for krypton and ～±11° for xenon.