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1.
Phys Rev Lett ; 132(23): 231903, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38905689

RESUMO

The cross section of the process e^{+}e^{-}→π^{+}π^{-} has been measured in the center-of-mass energy range from 0.32 to 1.2 GeV with the CMD-3 detector at the electron-positron collider VEPP-2000. The measurement is based on an integrated luminosity of about 88 pb^{-1}, of which 62 pb^{-1} represent a complete dataset collected by CMD-3 at center-of-mass energies below 1 GeV. In the dominant region near the ρ resonance a systematic uncertainty of 0.7% was achieved. The implications of the presented results for the evaluation of the hadronic contribution to the anomalous magnetic moment of the muon are discussed.

2.
Zh Vopr Neirokhir Im N N Burdenko ; 85(5): 110-115, 2021.
Artigo em Russo | MEDLINE | ID: mdl-34714011

RESUMO

Traumatic brain injury (TBI) affects about 50 million people in the world every year. Posttraumatic epilepsy (PTE) is a significant complication of TBI of any severity. PTE occurs in 20% of patients with TBI. Treatment of patients with PTE is particularly difficult due to obvious tendency towards drug resistance. Currently, there are no validated predictive biomarkers for PTE. Development of a system of validated predictive markers would improve PTE prediction quality and therapeutic approach for these patients. This review is devoted to the current data on the most perspective predictive biomarkers of PTE for clinical practice.


Assuntos
Lesões Encefálicas Traumáticas , Epilepsia Pós-Traumática , Biomarcadores , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico , Lesões Encefálicas Traumáticas/terapia , Epilepsia Pós-Traumática/diagnóstico , Epilepsia Pós-Traumática/etiologia , Humanos
3.
Artigo em Russo | MEDLINE | ID: mdl-33901354

RESUMO

The article considers the influence of natural and climatic factors on population health. According to expert judgments, natural and climatic factors are among causes of unwell feeling of significant part of Russians. The purpose of the study is to determine in what limits and in what way the climate affects citizen health. The various natural and climatic factors were analyzed in the context of their differentiation by regions and the level of impact on human organism. It is determined that natural and climatic factors cause the development of chronic diseases in Russia. On the basis of data comparative analysis concerning nature of acquired diseases and migration level it is concluded that chronic diseases of population can contribute into process of "climate migration".


Assuntos
Clima , Humanos , Morbidade , Federação Russa/epidemiologia
4.
Mol Biol (Mosk) ; 52(2): 326-332, 2018.
Artigo em Russo | MEDLINE | ID: mdl-29695702

RESUMO

Nowadays, allergic disorders have become one of the most important social problems in the world. This can be related to the advent of new allergenic agents in the environment, as well as an increasing density of human contact with known allergens, including various proteins. Thus, the development of computer programs designed for the prediction of allergenic properties of proteins becomes one of the urgent tasks of mo dern bioinformatics. Previously we developed a web accessible Allpred Program (http://www-bionet.sscc.ru/ psd/cgi-bin/programs/Allpred/allpred.cgi) that allows users to assess the allergenicity of proteins by taking into account the characteristics of their spatial structure. In this paper, using AllPred, we predicted the allergenicity of proteins from 462 archaea and bacteria species for which a complete genome was available. The segregation of considered proteins on archaea and bacteria has shown that allergens are predicted more often among archaea than among bacteria. The division of these proteins into groups according to their intracellular localization has revealed that the majority of allergenic proteins were among the secreted proteins. The application of methods for predicting the level of gene expression of microorganisms based on DNA sequence analysis showed a statistically significant relationship between the expression level of the proteins and their allergenicity. This analysis has revealed that potentially allergenic proteins were more common among highly expressed proteins. Sorting microorganisms into the pathogenic and nonpathogenic groups has shown that pathogens can potentially be more allergenic because of a statistically significant greater number of allergens predicted among their proteins.


Assuntos
Archaea/imunologia , Proteínas Arqueais/imunologia , Bactérias/imunologia , Proteínas de Bactérias/imunologia , Hipersensibilidade/imunologia , Modelos Imunológicos , Software , Humanos , Hipersensibilidade/patologia , Valor Preditivo dos Testes
5.
Mol Biol (Mosk) ; 51(5): 870-880, 2017.
Artigo em Russo | MEDLINE | ID: mdl-29116075

RESUMO

Profiles of alternative mRNA isoforms have been determined in three brain regions of rats from an aggressive and a tame line selected for 74 generations. Among 2319 genes with alternatively spliced exons, approximately 84% were confirmed by analyzing public databases. Based on Gene Ontology-guided clustering of alternatively spliced genes, it has been found that the sample was enriched in synapse-specific genes (FDR < 10^(-17)). Patterns of gene expression in the brains of animals with genetically determined high or low aggression were more frequently found to differ in the use of alternatively spliced exons than in animals environmentally conditioned for increased or lowered propensity to aggression. For the Adcyap1r1 gene, five alternatively spliced mRNA isoforms have been represented differentially in aggressive animals. A detailed analysis of the gene that encodes glutamate ionotropic receptor NMDA type subunit 1 (Grin1) has confirmed significant differences in the levels of its alternatively spliced isoforms in certain brain regions of tame and aggressive rats. These differences may affect the behavior in rats genetically selected for aggression levels.


Assuntos
Agressão , Processamento Alternativo , Encéfalo/metabolismo , RNA Mensageiro/metabolismo , Receptores de N-Metil-D-Aspartato/biossíntese , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/biossíntese , Animais , Masculino , RNA Mensageiro/genética , Ratos , Receptores de N-Metil-D-Aspartato/genética , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Seleção Artificial
6.
Klin Lab Diagn ; 62(5): 305-309, 2017.
Artigo em Russo | MEDLINE | ID: mdl-31509662

RESUMO

The mucoviscidosis is one of frequent monogenic diseases. In Russia, in case of mucoviscidosis carrying out of DNA-diagnostic is optional. However, its application permits shortening time of diagnosing, increasing efficiency of of therapeutic treatment and preventing secondary manifestation of disease in family. The DNA-diagnostic using panels on frequent mutations in gene CFTR is recommended in cases of uncertain clinical picture and under borderline values of specific laboratory indices. In Russia, application of such panels permit detecting up to 90% of pathological alleles in gene CFTR. To detect more rare alleles the Sanger sequencing is traditionally applied. Lately, highly productive sequencing techniques became available to detect rare mutations. The actual article presents evaluation of efficiency of application of test-system based on technology of target sequencing for detecting mutations unidentified at primary DNA-diagnostic. Besides, in two patients with mucoviscidosis the application of highly productive sequencing techniques permitted to identify previously unknown nonsense mutations Q1038X (c.3112C>T) и W1310X (c.3930G>A).

7.
Klin Lab Diagn ; 59(10): 40-5, 2014 Oct.
Artigo em Russo | MEDLINE | ID: mdl-25884079

RESUMO

To decrease dependence of effectiveness of isolation of nucleic acids of composition and amount of applied sample a kit was developed for hybridization extraction of DNA HBV RNA HCV and RNA HIV from blood serum in two formats--using up to 250 mkl and up to 1 ml of sample. This kit, in complex with kits for detection using polymerase chain reaction technique in real-time, forms a test characterized by high analytical sensitivity i.e. HBV50 copies per ml, HCV37.5 copies per ml, HIV 13 copies per ml. The developed kit for extraction of target nucleic acids permits to get rid of total DNA and inhibited effect of heparin. It can be adapted for application wit factors B and automated stations of sample preparation.


Assuntos
DNA Viral , Infecções por HIV/sangue , Hepatite B/sangue , Hepatite C/sangue , Kit de Reagentes para Diagnóstico , DNA Viral/sangue , DNA Viral/isolamento & purificação , HIV-1 , Hepacivirus , Vírus da Hepatite B , Humanos , RNA Viral/sangue , RNA Viral/isolamento & purificação
8.
Bioorg Khim ; 36(6): 802-14, 2010.
Artigo em Russo | MEDLINE | ID: mdl-21317947

RESUMO

The isothermal amplification of reporter signal via limited probe extension (minisequencing) upon hybridization of nucleic acids has been studied. The intensity of reporter signal has been shown to increase due to enzymatic labeling of multiple probes upon consecutive hybridization with one DNA template both in homophase and heterophase assays using various kinds of detection signal: radioisotope label, fluorescent label, and enzyme-linked assay. The kinetic scheme of the process has been proposed and kinetic parameters for each step have been determined. The signal intensity has been shown to correlate with physicochemical characteristics of both complexes: probe/DNA and product/DNA. The maximum intensity has been observed at minimal difference between the thermodynamic stability of these complexes, provided the reaction temperature has been adjusted near their melting temperature values; rising or lowering the reaction temperature reduces the amount of reporting product. The signal intensity has been shown to decrease significantly upon hybridization with the DNA template containing single-nucleotide mismatches. Limited probe extension assay is useful not only for detection of DNA template but also for its quantitative characterization.


Assuntos
DNA/análise , Oligonucleotídeos/química , Análise de Sequência de DNA/métodos , DNA/química , Hibridização de Ácido Nucleico , Termodinâmica
9.
Anal Biochem ; 393(1): 135-7, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19523915

RESUMO

Polymerase chain reaction (PCR) is widely used to detect specific DNA sequences for purposes of microbial identification, clinical diagnosis, and basic research. The most pernicious problem plaguing this technique is contamination of PCR reagents with previously amplified material. We propose a useful tool for PCR reagent purification from contaminating nucleic acid using DEAE-cellulose and present the analysis of this technique for both decontamination efficiency and an effect on the reagent activity. We also show the suitability of the proposed approach for decontamination of the Taq polymerase, monoclonal antibodies to Taq polymerase, and Moloney murine leukemia virus (M-MLV) reverse transcriptase.


Assuntos
DEAE-Celulose/química , Reação em Cadeia da Polimerase/métodos , Descontaminação , Indicadores e Reagentes/isolamento & purificação , Taq Polimerase/metabolismo
10.
J Cell Biol ; 143(3): 645-57, 1998 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-9813087

RESUMO

The cystic fibrosis transmembrane conductance regulator (CFTR) is a chloride channel that is defective in cystic fibrosis, and has also been closely associated with ATP permeability in cells. Using a Xenopus oocyte cRNA expression system, we have evaluated the molecular mechanisms that control CFTR-modulated ATP release. CFTR-modulated ATP release was dependent on both cAMP activation and a gradient change in the extracellular chloride concentration. Activation of ATP release occurred within a narrow concentration range of external Cl- that was similar to that reported in airway surface fluid. Mutagenesis of CFTR demonstrated that Cl- conductance and ATP release regulatory properties could be dissociated to different regions of the CFTR protein. Despite the lack of a need for Cl- conductance through CFTR to modulate ATP release, alterations in channel pore residues R347 and R334 caused changes in the relative ability of different halides to activate ATP efflux (wtCFTR, Cl >> Br; R347P, Cl >> Br; R347E, Br >> Cl; R334W, Cl = Br). We hypothesize that residues R347 and R334 may contribute a Cl- binding site within the CFTR channel pore that is necessary for activation of ATP efflux in response to increases of extracellular Cl-. In summary, these findings suggest a novel chloride sensor mechanism by which CFTR is capable of responding to changes in the extracellular chloride concentration by modulating the activity of an unidentified ATP efflux pathway. This pathway may play an important role in maintaining fluid and electrolyte balance in the airway through purinergic regulation of epithelial cells. Insight into these molecular mechanisms enhances our understanding of pathogenesis in the cystic fibrosis lung.


Assuntos
Trifosfato de Adenosina/metabolismo , Cloretos/fisiologia , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Fibrose Cística/metabolismo , 1-Metil-3-Isobutilxantina/farmacologia , Animais , Colforsina/farmacologia , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Condutividade Elétrica , Feminino , Expressão Gênica , Potenciais da Membrana/fisiologia , Oócitos/metabolismo , Xenopus laevis
11.
Mol Gen Mikrobiol Virusol ; (3): 8-13, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19705776

RESUMO

An uncompetitive exogenous internal amplification control method (EIAC) was developed on the basis of short synthetic DNA segment, whose amplification can be detected in real time by UFA spectroscopy principle. The EIAC was shown to be useful as internal control in diagnostic test systems based on DNA or RNA detection by multiplex real-time PCR. It can be applied to assess the quality of extracted DNA or RNA, and also to detect and study the factors causing PCR inhibition and earlier plateau effect.


Assuntos
Oligonucleotídeos/química , Reação em Cadeia da Polimerase/métodos , Fluorescência , Kit de Reagentes para Diagnóstico
12.
Artigo em Russo | MEDLINE | ID: mdl-19795810

RESUMO

The aim of present study was to reveal the genetic effects on social dominance and patterns of agonistic behaviors in social partners. The study was carried out in adult male mice of three inbred strains BALB/cLac, CBA/Lac and PT using an ethological model of social hierarchy, which is characterised by the minimal size and genetic heterogeneity (two males of different genotypes). We used a neutral territory as the experimental territorial condition for the establishment of social hierarchy. Rank asymmetry in aggressive and defensive behaviors was quickly formed during the first day after the production of the social. Significant interstrain differences in time patterns ofagonistic behavior in dominants and subordinates as well as in the level of social dominance determined as a proportion of dominant animals in the strain were observed. In was shown that, in laboratory mice, the genotype could markedly influence social dominance and the patterns of agonistic behavior in social partners.


Assuntos
Comportamento Agonístico/fisiologia , Dominação-Subordinação , Comportamento Social , Animais , Masculino , Camundongos , Predomínio Social , Especificidade da Espécie
13.
Biochemistry (Mosc) ; 73(9): 1007-17, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18976218

RESUMO

A new method is proposed for estimation of polymerase activities using fluorescence detection during isothermal reaction. The method allows simultaneous determination of DNA-dependent DNA polymerase and 5'-3'-exonuclease activities using amplifiers supplied with an optical module for fluorescence detection under real-time conditions. Different primer-template combinations used as polymerase substrates were compared. Primer elongation (polymerase reaction) is detected by changes in SYBR Green I fluorescence upon binding to dsDNA during reaction; nuclease activities are detected by changes in fluorescence due to cleavage of the probe, containing the reporter fluorophore and fluorescence quencher, and hybridized in advance to the template single-stranded region. It was also shown that the method can be used for determination of relative activities of DNA polymerase preparations, estimation of temperature-time dissociation parameters of polymerase complexes with specific antibodies to its active center, and analysis of effects of inhibitors and activators of different nature on reaction rates of dsDNA polymerization and 5'-3'-exonuclease cleavage by polymerase. The method can be also used for estimation of endonuclease activities of DNA polymerases.


Assuntos
Bioquímica/métodos , DNA Polimerase Dirigida por DNA/isolamento & purificação , Exonucleases/isolamento & purificação , Primers do DNA/química , Primers do DNA/metabolismo , DNA Polimerase Dirigida por DNA/química , DNA Polimerase Dirigida por DNA/metabolismo , Endonucleases/química , Endonucleases/isolamento & purificação , Endonucleases/metabolismo , Exonucleases/química , Exonucleases/metabolismo , Fluorescência , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Taq Polimerase , Temperatura , Moldes Genéticos , Fatores de Tempo
14.
Artigo em Russo | MEDLINE | ID: mdl-18666570

RESUMO

Sexual behaviour and testosterone output in response to a receptive female were investigated in male mice of three inbred strains BALB/cLac, CBA/Lac and PT at puberty (45 days of age) and in adulthood (90 days of age). The animals were exposed for 10 min to a receptive female separated by a plastic grill, which would not allow contact between male and female. Male and female behaviour was recorded by measuring the time the male or female spent at the grill and the number of approaches to it (sexual motivation). The grill was then removed and the number of mounts and chemoinvestigatory behavior towards a female (nasal and anogenital sniffing) was recorded for each male. An increase in serum concentration and testicular content of testosterone was used as an endocrine index of the sensitivity to female pheromones. It has been shown the significant genotype and developmental effects on sexual behaviour and the hormonal response to sexual stimuli. The pubertal BALB/cLac males were characterised by the adult pattern of sexual motivation, chemoinvestigatory behaviour and the evident testosterone respond to a female. Males of the strain PT showed the lowest sexual motivation, chemoinvestigatory behavior towards a receptive female and no testosterone responses at both ages. This is a very different situation with the CBA/Lac's who showed the developmental increase in the sexual motivation, sniffing behaviour and the endocrine reflex, and the highest level of sexual behaviour but the moderate testosterone respond to a female at adulthood. The data obtained suggest genotype related asynchrony in maturation of the olfactory system, pituitary-gonadal axis and neural circuits of sexual behavior, and their independent genetic control. So, the set of mice strains investigated represents a useful tool for genetic and endocrine study of sexual behavior and the chemosensory control of testicular steroidogenesis.


Assuntos
Comportamento Sexual Animal/fisiologia , Maturidade Sexual/fisiologia , Animais , Feminino , Genótipo , Masculino , Camundongos , Camundongos Endogâmicos , Especificidade da Espécie , Testículo/metabolismo , Testosterona/sangue
15.
Stomatologiia (Mosk) ; 87(3): 28-31, 2008.
Artigo em Russo | MEDLINE | ID: mdl-18577919

RESUMO

From position of typological variability of physiological individuality concept-functional constitution types - the principle of organism integrity was substantiated for stomatological pathology. There were isolated typical and specific reactions of cardiac-vessel system in patients with different resistance to periodontal diseases. Each functional type - patients with different levels of usual motion activity - had their own physiological peculiarities of parameters of system blood flow, physical capacity for work and cardiac activity regulation, that determined individual typological organism reaction in cases of maxillo-facial system pathology. The received data gives the objective base for physiological approach to single out the extreme variants of norm for forming risk contingent and groups of resistant people to periodontal diseases.


Assuntos
Gengiva/irrigação sanguínea , Gengiva/fisiopatologia , Frequência Cardíaca/fisiologia , Periodontite/fisiopatologia , Esforço Físico , Aptidão Física , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
J Clin Invest ; 100(5): 1079-88, 1997 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9276724

RESUMO

Abnormal folding of mutant cystic fibrosis transmembrane conductance regulator (CFTR) and subsequent degradation in the endoplasmic reticulum is the basis for most cases of cystic fibrosis. Structural differences between wild-type (WT) and mutant proteins, however, remain unknown. Here we examine the intracellular trafficking, degradation, and transmembrane topology of two mutant CFTR proteins, G85E and G91R, each of which contains an additional charged residue within the first putative transmembrane helix (TM1). In microinjected Xenopus laevis oocytes, these mutations markedly disrupted CFTR plasma membrane chloride channel activity. G85E and G91R mutants (but not a conservative mutant, G91A) failed to acquire complex N-linked carbohydrates, and were rapidly degraded before reaching the Golgi complex thus exhibiting a trafficking phenotype similar to DeltaF508 CFTR. Topologic analysis revealed that neither G85E nor G91R mutations disrupted CFTR NH2 terminus transmembrane topology. Instead, WT as well as mutant TM1 spanned the membrane in the predicted C-trans (type II) orientation, and residues 85E and 91R were localized within or adjacent to the plane of the lipid bilayer. To understand how these charged residues might provide structural cues for ER degradation, we examined the stability of WT, G85E, and G91R CFTR proteins truncated at codons 188, 393, 589, or 836 (after TM2, TM6, the first nucleotide binding domain, or the R domain, respectively). These results indicated that G85E and G91R mutations affected CFTR folding, not by gross disruption of transmembrane assembly, but rather through insertion of a charged residue within the plane of the bilayer, which in turn influenced higher order tertiary structure.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/química , Retículo Endoplasmático/metabolismo , Animais , Canais de Cloreto/fisiologia , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Feminino , Mutação , Dobramento de Proteína , Coelhos , Proteínas Recombinantes/biossíntese , Xenopus
17.
Mol Biol Cell ; 9(9): 2681-97, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9725920

RESUMO

Topogenic determinants that direct protein topology at the endoplasmic reticulum membrane usually function with high fidelity to establish a uniform topological orientation for any given polypeptide. Here we show, however, that through the coupling of sequential translocation events, native topogenic determinants are capable of generating two alternate transmembrane structures at the endoplasmic reticulum membrane. Using defined chimeric and epitope-tagged full-length proteins, we found that topogenic activities of two C-trans (type II) signal anchor sequences, encoded within the seventh and eighth transmembrane (TM) segments of human P-glycoprotein were directly coupled by an inefficient stop transfer (ST) sequence (TM7b) contained within the C-terminus half of TM7. Remarkably, these activities enabled TM7 to achieve both a single- and a double-spanning TM topology with nearly equal efficiency. In addition, ST and C-trans signal anchor activities encoded by TM8 were tightly linked to the weak ST activity, and hence topological fate, of TM7b. This interaction enabled TM8 to span the membrane in either a type I or a type II orientation. Pleiotropic structural features contributing to this unusual topogenic behavior included 1) a short, flexible peptide loop connecting TM7a and TM7b, 2) hydrophobic residues within TM7b, and 3) hydrophilic residues between TM7b and TM8.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Retículo Endoplasmático/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Sequência de Aminoácidos , Animais , Humanos , Membranas Intracelulares/metabolismo , Dados de Sequência Molecular , Xenopus laevis
18.
Mol Biol Cell ; 11(9): 2973-85, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10982394

RESUMO

The topology of most eukaryotic polytopic membrane proteins is established cotranslationally in the endoplasmic reticulum (ER) through a series of coordinated translocation and membrane integration events. For the human aquaporin water channel AQP1, however, the initial four-segment-spanning topology at the ER membrane differs from the mature six-segment-spanning topology at the plasma membrane. Here we use epitope-tagged AQP1 constructs to follow the transmembrane (TM) orientation of key internal peptide loops in Xenopus oocyte and cell-free systems. This analysis revealed that AQP1 maturation in the ER involves a novel topological reorientation of three internal TM segments and two peptide loops. After the synthesis of TMs 4-6, TM3 underwent a 180-degree rotation in which TM3 C-terminal flanking residues were translocated from their initial cytosolic location into the ER lumen and N-terminal flanking residues underwent retrograde translocation from the ER lumen to the cytosol. These events convert TM3 from a type I to a type II topology and reposition TM2 and TM4 into transmembrane conformations consistent with the predicted six-segment-spanning AQP1 topology. AQP1 topological reorientation was also associated with maturation from a protease-sensitive conformation to a protease-resistant structure with water channel function. These studies demonstrate that initial protein topology established via cotranslational translocation events in the ER is dynamic and may be modified by subsequent steps of folding and/or maturation.


Assuntos
Aquaporinas/química , Aquaporinas/fisiologia , Membrana Celular/fisiologia , Retículo Endoplasmático/fisiologia , Sequência de Aminoácidos , Animais , Aquaporina 1 , Aquaporinas/genética , Sequência de Bases , Antígenos de Grupos Sanguíneos , Membrana Celular/ultraestrutura , Permeabilidade da Membrana Celular , DNA Complementar , Retículo Endoplasmático/ultraestrutura , Feminino , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos Antissenso , Oócitos/fisiologia , Fragmentos de Peptídeos/química , Biossíntese de Proteínas , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Transcrição Gênica , Água/metabolismo , Xenopus laevis
19.
Artigo em Russo | MEDLINE | ID: mdl-17642378

RESUMO

Asymmetry of social rank in the competition for food and female was studied using the social dominance model with only two male mice. Marking activity was recorded as a useful indicator of the social status. Social rank was determined by asymmetry in aggressive behavior. A food test was presented for 10 min daily within 5 days of the experiment, whereas a sexual test was performed only on the 5th day for 30 min. Marking behavior was estimated twice: before the first interaction and on the 4th day of the experiment. The competition for food was accompanied by active attacks, escapes, vertical defense postures, and sniffing. The level of aggression, sniffing, and food activity was higher in dominant than submissive males. Time course of aggressive, defensive, and sniffing behaviors was characterized by maximum scores in the period of formation of social hierarchy; however, the rate of food activity in this period was low and increased only to the 4th day. Introduction of a receptive female into the male group with the stable social hierarchy stimulated the intermale aggression, defensive and sniffing behaviors. Dominant males were characterized by a greater number of victories over and sniffing contacts with both male and female. Marking activity was also more intense in dominants. Thus, significant unidirectional rank differences in agonistic, sniffing, food, sexual, and marking behaviors were shown on the social dominance model with the minimum number of partners.


Assuntos
Agressão , Comportamento Competitivo , Dominação-Subordinação , Comportamento Alimentar , Comportamento Sexual Animal , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos
20.
Artigo em Russo | MEDLINE | ID: mdl-18064899

RESUMO

In laboratory male mice the effects of social hierarchy on hormonal and spermatogenic testicular function, accessory organs and testicular weights, sexual behaviour have been investigated using an experimental model of social hierarchy, which is characterised by a minimal size (two male mice) and 5 days period of social interactions. The social rank of the partners was detected by asymmetry in aggressive behaviour. Using the experimental condition, when the both partners have no preferences for exclusive use of area we demonstrated that there were no rank differences in the number of mounts and testicular testosterone content. Nevertheless a rank asymmetry in the male sniffing behaviour towards a receptive female, weights of the testes, seminal vesicles, epididymes and the number of epididymal sperm was kept up in a stable social group. Social dominance was found to affect negatively on testicular testosterone increase in response to introduction of a receptive female and sexual attractiveness of male to a receptive female in both dominant and subordinate males. The results obtained demonstrate the impact of social hierarchy on reproduction in laboratory male mice, particular in respect of spermatogenesis and the testicular testosterone in response to a receptive female.


Assuntos
Dominação-Subordinação , Epididimo/fisiologia , Hierarquia Social , Comportamento Sexual Animal , Espermatogênese , Testículo/fisiologia , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos , Tamanho do Órgão , Espermatozoides/citologia , Espermatozoides/fisiologia , Testosterona/sangue
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