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1.
Biofizika ; 55(3): 445-50, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20586323

RESUMO

A hypothesis has been advanced that logically combines "contradictory" facts concerning the early mammalian development and shows a natural relationship between the embryos developing from a fertilized ovum and from cells of the inner cell mass of blastocyst. When studying the theoretical questions of cloning, it is necessary to take into consideration the peculiarities of prenatal mammalian ontogenesis, which make themselves evident upon comparison with other animals. The absence of yolk in the mammalian ovum defines sharp differences in the early development between mammals and other Amniota. The whole asynchronic cleavage results in the formation of the morula followed by the blastocyst, which hatches from zona pellucida and is implanted into the uterus tissue. This fact allows us to consider the blastocyst as a mammalian larva, which is fed thanks to maternal organism. It is known that, in the body of a larva (blastocyst), a new embryo develops from some somatic cells. This process is known as a polyembryony, which is typical for the development of some parasitic insects. The polyembryony in turn is a variant of somatic embryogenesis, which is a form of asexual reproduction. Thus, two different embryos, "conceptus" and "embryo proper", have different origin: the first forms by the sexual way and the second, by the asexual. The investigation of the mechanisms of somatic embryogenesis in mammals will help us to find conditions necessary for the full reprograming of donor somatic nuclei and provide the successful development of reconstructed embryos.


Assuntos
Blastocisto/fisiologia , Clonagem de Organismos , Desenvolvimento Embrionário , Animais , Blastocisto/citologia , Massa Celular Interna do Blastocisto/citologia , Massa Celular Interna do Blastocisto/fisiologia , Mamíferos , Reprodução/fisiologia
2.
Biofizika ; 55(3): 481-5, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20586327

RESUMO

A novel approach to the establishment of genetically modified human embryonic stem cell (hESC) lines has been developed, and it has been shown that mutant hESC may be derived from affected embryos after preimplantation genetic diagnosis screening for a particular single gene disorder. Here we provide the description of embryo and cell manipulation procedures, diagnostic lay out, analysis of the efficiency of embryo development and hESC establishment, as well as developments for hESC derivation in animal free conditions. The high efficiency of the approach (50%) is especially crucial in the work with rare and unique resources, such as genetically screened embryos necessary for the derivation of hESC lines representative of specific genetic diseases.


Assuntos
Células-Tronco Embrionárias/citologia , Blastocisto/citologia , Diferenciação Celular , Linhagem Celular , Doenças Genéticas Inatas/embriologia , Doenças Genéticas Inatas/genética , Engenharia Genética , Humanos , Microdissecção/instrumentação , Mutação , Diagnóstico Pré-Implantação
3.
Biofizika ; 55(3): 493-5, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20586329

RESUMO

Data characterizing the kinetics of the contraction of trabeculae and the intertrabelcular tissue have been obtained. It has been concluded that trabeculae can act as conductors/transmitters of contraction across the myocardium and play a leading role in this process, while the functional role of the intertrabelcular tissue is secondary and more passive, and consists in the optimization and support of the contractile process.


Assuntos
Coração/fisiologia , Sódio/farmacologia , Animais , Cátions Monovalentes , Temperatura Baixa , Meios de Cultura , Átrios do Coração , Contração Miocárdica , Rana temporaria
4.
Usp Fiziol Nauk ; 40(2): 87-109, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19505026

RESUMO

The main modern concepts on the consciousness nature are considered. Together with the dualistic concepts, there exist concepts the adherents of which find it possible to get to know the origin of consciousness on the basis of natural science. A critical analysis of those concepts brings the author to the conclusion that they do not solve the main problem of individual consciousness: how subjective elements of consciousness arise in the brain as a result of objectively registered processes. The main reason of failures to solve said problem is considered by the author in the fact that the subjective categories of consciousness are not really subject to science. Nevertheless, it does not mean the dualism is to be inevitably accepted. In fact, the subjective categories arise in the limits of a life the area of which is substantially wider than that of science. An original information and physical hypothesis is being set up that provides for necessary premises and conditions enabling the origination of subjective categories of consciousness during the progressive natural evolution of living systems.


Assuntos
Encéfalo/fisiologia , Estado de Consciência/fisiologia , Individualidade , Autoimagem , Inteligência Artificial , Evolução Biológica , Humanos , Teoria da Informação , Processos Mentais/fisiologia , Redes Neurais de Computação , Integração de Sistemas
5.
Morfologiia ; 131(2): 53-8, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17583010

RESUMO

Molecular layer of frog (Rana temporaria) cerebellum was studied using light and electron microscope after electrical stimulation of parallel fibers in presence of NO-generating compound. Under these conditions, significant swelling of axonal terminals (boutons) of granular cells and astrocyte processes (AP) with a loss of cytoplasmic elements. However, along with the damaged structures, intact boutons were found with synaptic vesicles and APs containing glycogen granules. It is suggested that the remaining viable APs are capable of forming 1) protective glial "wrappings" around damaged synapses or boutons, and 2) neuron-glial junctions, that are formed due to transmission of synaptic vesicles through the damaged membrane of bouton into AP containing glycogen granules. It is also proposed that the presence of glycogen in APs under conditions of oxygen and glucose deficit may serve as the source of such energy-containing substrates, such as glucose and ATP, and thus may provide for neuronal survival in pathological states (ischemia/hypoxia).


Assuntos
Astrócitos/ultraestrutura , Cerebelo/ultraestrutura , Junções Intercelulares/ultraestrutura , Neurônios/ultraestrutura , Sinapses/ultraestrutura , Trifosfato de Adenosina/metabolismo , Animais , Axônios/química , Axônios/ultraestrutura , Cerebelo/efeitos dos fármacos , Estimulação Elétrica , Glucose/metabolismo , Glicogênio/análise , Neuroglia/efeitos dos fármacos , Neuroglia/ultraestrutura , Neurônios/efeitos dos fármacos , Doadores de Óxido Nítrico/farmacologia , Rana temporaria
6.
Biofizika ; 52(2): 295-300, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17477057

RESUMO

The effect of the neurotoxin melittin on the activation of ion channels of excitable membrane, the plasmalemma of Characeae algae cells, isolated membrane patches of neurons of mollusc L. stagnalis and Vero cells was studied by the method of intracellular perfusion and the patch-clamp technique in inside-out configuration. It was shown that melittin disturbs the conductivity of plasmalemma and modifieds Ca(2+)-channels of plant membrane. The leakage current that appears by the action of melittin can be restored by substituting calmodulin for melittin. Melittin modifies K(+)-channels of animal cell membrane by disrupting the phospholipid matrix and forms conductive structures in the membrane by interacting with channel proteins, which is evidenced by the appearance of additional ion channels.


Assuntos
Canais de Cálcio/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Meliteno/farmacologia , Canais de Potássio/efeitos dos fármacos , Animais , Chlorocebus aethiops , Potenciais da Membrana/efeitos dos fármacos , Moluscos/citologia , Neurônios/efeitos dos fármacos , Nitella/citologia , Técnicas de Patch-Clamp , Células Vero
8.
Biofizika ; 50(1): 152-5, 2005.
Artigo em Russo | MEDLINE | ID: mdl-15759515

RESUMO

The paper is concerned with some problems of terminology, in particular the term "bioinformatics". In the last few years, the term "bioinformatics" has been intensively used among molecular biologists to indicate a subject that is only a constituent of genomics and is considered to involve a computer-assisted analysis of all data on nucleotide sequences of DNA. However, a wide circle of scientists, including biologists, physicists, mathematicians, and specialists in the field of cybernetics, informatics, and other disciplines have accepted and accept, as a rule, the "bioinformatics" as a synonym of science cybernetics and as a successor of this science. In this case, the subject of science "bioinformatics" should embrace not only genomics but practically all sections of the biological science. It should involve a study of information processes (storage, transfer, and processing of information, etc.) participating in the regulation and control at all levels of living systems, from macromolecules to the brain of higher animals and human.


Assuntos
Biologia Computacional , Federação Russa
9.
Tsitologiia ; 47(3): 214-9, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16706165

RESUMO

In the present work, cerebellar neural net injury was induced by toxic doses of NO-generative compound (NaNO2). A protective role of glial cells was revealed in such conditions. The present results were compared with those of the previous work concerning the action of high concentration glutamate on the frog cerebellum (Samosudova et al., 1996). In both cases we observed the appearance of spiral-like structures--"wrappers)"--involving several rows of transformed glial processes with smaller width and bridges connecting the inner sides of row (autotypic contact). A statistic analysis was made according to both previous and present data. We calculated the number and width of rows, and intervals between bridges depending on experimental conditions. As the injury increased (stimulation in the NO-presence), the row number in "wrappers" also increased, while the row width and intervals between bridges decreased. The presence of autotypic contacts in glial "wrappers" enables us to suppose the involvement of adhesive proteins--cadherins in its formation. The obtained data suggested that the formation of spiral structures--"wrappers" may be regarded as a compensative-adaptive reaction on the injury of cerebellar neural net glutamate and NO-generative compounds.


Assuntos
Cerebelo/fisiologia , Rede Nervosa/fisiologia , Animais , Comunicação Celular , Doenças Cerebelares/etiologia , Doenças Cerebelares/fisiopatologia , Cerebelo/lesões , Cerebelo/patologia , Cerebelo/ultraestrutura , Modelos Animais de Doenças , Rede Nervosa/lesões , Rede Nervosa/patologia , Rede Nervosa/ultraestrutura , Neuroglia/fisiologia , Neuroglia/ultraestrutura , Doadores de Óxido Nítrico/efeitos adversos , Rana temporaria
10.
Tsitologiia ; 47(8): 686-91, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16706211

RESUMO

Method of 3-D reconstruction approaches for early mouse embryo in preimplantation stages was modified. The developed technique is based on application of light microscopy of serial thin sections and well known soft operating. The designed method enabled us 1) to get serial sections of a single mouse embryo; 2) to create an orthogonal system independent on the sample for orientation of virtual sections. The adequacy of 3-DR protocol was checked on reconstruction of air bubbles embedded in epoxy resin as a model of sphere.


Assuntos
Blastocisto/ultraestrutura , Imageamento Tridimensional , Animais , Técnicas de Cultura Embrionária , Camundongos , Camundongos Endogâmicos
11.
Biofizika ; 45(2): 329-37, 2000.
Artigo em Russo | MEDLINE | ID: mdl-10776548

RESUMO

The role of tremor and drift in the formation of primary receptive fields and signals of space-frequency transformations at the level of retina fovea centralies cells was investigated. The mechanism of organization of direct informational connection between photoreceptors, horizontal and bipolar cells was determined, and the formulas for the synthesis of visual information signals were derived taking into account the frequency of participation of image elements. It is shown that tremor and drift are those mechanophysical processes whose mutual cooperation leads to the formation of the hysteresis signal informationally sufficient for monochrome and polychrome visual recognition.


Assuntos
Movimentos Oculares/fisiologia , Retina/fisiologia , Percepção Visual/fisiologia , Fóvea Central/citologia , Fóvea Central/fisiologia , Humanos , Modelos Biológicos , Retina/citologia
12.
Vestn Ross Akad Med Nauk ; (6): 35-8, 1999.
Artigo em Russo | MEDLINE | ID: mdl-10432862

RESUMO

This study has attempted to show that consciousness (sense) can develop only in the living systems during natural evolution based on self-organization. While modelling the systems experimentally, it is impossible to reproduce consciousness phenomena. This fact points to the global differences in the principles of management of living systems as compared to the artificial ones. Due to the existence of various forms of consciousness (from the simplest forms, such as sensing, perception, and feeling to the most complicated ones, such as motivation and desire), the living organisms are capable to interpret the complex neurodynamics of the brain into a simple and functionally significant integral form for them. Owing to consciousness, the behavior of living systems at the highest level of evolution (a human being) becomes an indeterminate behavior with the clearly expressed position of will freedom; it is also important that through consciousness an individual can influence different physiological mechanisms of living organisms.


Assuntos
Encéfalo/fisiologia , Estado de Consciência/fisiologia , Atividades Humanas , Animais , Comportamento Animal/fisiologia , Humanos
15.
Biofizika ; 44(1): 137-40, 1999.
Artigo em Russo | MEDLINE | ID: mdl-10330591

RESUMO

The action of nonthermal electromagnetic radiation (EMR) of the millimeter range on the early development of murine and sea urchin embryos was investigated. An MRTA-01E-03 generator with a frequency of 54-78 GHz and radiation intensity of 0.06 mWt/cm2 was used. The embryos were irradiated during 30 min at the stage of two blastomeres. The number of murine embryos that reached the blastocyst stage increased (up to 97.3% in comparison with 87.5% in control). The total time of cultivation up to the blastocyst stage was also shorter (72 h) than in control (96 h). The irradiation had effect on the development of sea urchin embryos only if embryos with a weakened viability were tested. The results indicate that millimeter electromagnetic radiation has a stimulating effect on the early development of embryos, increasing the resistance of embryos to unfavorable environmental conditions.


Assuntos
Campos Eletromagnéticos , Desenvolvimento Embrionário e Fetal/efeitos da radiação , Ouriços-do-Mar/embriologia , Animais , Embrião não Mamífero/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA
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