Search PubMed⌕ Search

Biomedical subjects

R K Danilov

Publications and source records attributed to R K Danilov.

At least 19 recordsLinked to original sources

[Morphofunctional characteristics of cell death in the epidermis in gunshot damage to rat skin under experimental conditions].

Different types epidermocyte death were considered in a model of skin gunshot injury in albino rats, Using light microscopy, cytophotometry and immunocytochemistry. Epidermocyte death was characterized by various morphological changes of nuclei, spatial localization of dying cells and different intensity of cellular death, that was registered in all the experimental terms. Cell alterations of necrotic, oncotic and apoptotic types were observed. Oncotic and necrotic type keratinocyte death prevailed in early and middle stages of regenerative histogenesis due to structural and metabolic organic disorders in the skin: in later stages distinctly manifested apoptotic cell death is more possible. However it is more probable that the majority of such cells completes their cycle with necrosis. This is connected to the fact that apoptosis is an energy-dependent process as caspase-activating adapter proteins contact with mitochondrial membranes. Gunshot injury had likely caused definite changes in molecular mechanisms of proliferative processes regulation, cell differentiation and death, leading to accumulation of pathologically altered cells in the epidermis.

Animals↗

[Experimental and histological analysis of histogenesis and tissue regeneration (some results of the 20th century and perspectives on further research)].

The article is devoted to theoretical analysis of certain achievements in the area of cellular and tissue biology. Evolutional laws of tissue development, theory of divergent differentiation of histological structures, conception of cellular-differon tissue organization, formulated earlier were completely suitable for analysis of processes of development and regeneration of living systems at different structural levels of organization. System-forming plasmalemmas, receptor-transductor and adaptive properties were related to most important characteristics of living systems that can be experimentally histologically analysed. Morphofunctional signs of differons and histions and tissue classifications were considered.

Adaptation, Physiological↗

[The morphofunctional characteristics of connective tissue regeneration in the rat dermis after a gunshot injury].

Gunshot injury causes a complex of changes in perinecrotic area covering all tissue structures of skin which is discussed as a systemic organ disintegration, including disintegration of dermal differons. Connective tissue regeneration is reflected by a determined process. Replacement of a defect with granulation tissue should be considered as a reparative regeneration. Peculiarities of fibroblasts proliferation and differentiation in perinecrotic area indicate the prevalence of regenerative histogenesis features.

Animals↗

[The criteria of cardiac muscle tissue viability under experimental and clinical conditions].

Comparative analysis of cardiac muscular tissue reactivity in myocardial hypertrophy development in experimental and clinical conditions was performed. Stereotyped reactions to overload were distinguished at intracellular, cellular and tissue levels. Cardiac muscular tissue vital activity was estimated through criteria of "chronos", "morphos", "quantum" and "turnover". It was shown that disruption of genetically determined correlation between processes of proliferation, differentiation and death of cardiomyocytes was a common regularity of cardiomyogenesis in formation of myocardial hypertrophy.

Adult↗

[The formation of motor units in vertebrates (a histophysiological analysis)].

In motor unit anlage successive formation of morphophysiological and biochemical components of system-forming units (histophysiological compartments) occurs. Simultaneously functional differentiation of motor units takes place, based on morphological, biochemical and functional heterogeneity of nervous, muscular and synaptic motor unit components. Intrinsic genetic programmes of main nervous and skeletal muscular tissue differons are the leading ones in early stages of embryogenesis. Morphofunctional base for realization of neurogenic control of skeletal musculature fibres histochemical differentiation forms in muscle anlage. Genetic programmes of two tissues development come to direct (contact) interaction through outer regions of cell membranes: motor neurons participation in skeletal muscular tissue histogenesis, especially on the stage of muscular tubules differentiation into muscular fibres of certain histophysiological type is essential. Most complicated changes are observed in postsynaptic membrane area. This allows to emphasize the development of the symphast nucleo-sarcoplasmic compartment. In further, adaptive changes and morphological manifestations of skeletal muscular tissue genetic programme realization arise in myogenesis with motor neurons role progressively increasing and becoming the predominant one.

Animals↗

[The proliferation, differentiation and death of cardiomyocytes during exposure to an antioxidant].

Influence of ionolum--vitamin E analog on differentiation, proliferative activity, cell death and content of products of lipid peroxide oxidation in chick embryo cardiac muscular tissue was studied in normal embryogenesis and in myocardial hypertrophy development. Administration of antioxidant to chick embryo was shown to result in intensified and prolonged proliferation, delayed differentiation and reduced cardiomyocyte death index both in normal histogenesis and in myocardial hypertrophy development. Use of the drug leads to viability increase in embryos exposed to extreme environmental factor action.

Animals↗

[The regeneration of skeletal muscle tissue after a gunshot injury].

Peculiarities of skeletal muscular tissue regeneration were studied after inflicting the gunshot damage in rabbits. Phase 1 of the wound process consists of forming of the posttraumatic necrosis zone, disintegration of skeletal muscular tissue differons and macrophage activation. Proliferation phase starts 36 hrs after the wound was inflicted and includes myosatellitocyte activation and proliferation and myoblast appearance. The process of myogenic cell differentiation is similar to whose in embryonal myogenesis. Two ways of symplast appearance were described--the myoblastic one and the one by means of muscular bud growth from the viable muscular fiber. Regenerative and degenerative processes run simultaneously in all experiments studied. Definitive fibres located on a distance from the wound die so as the newly formed ones (sources of the delayed necrosis nidi). Results obtained allow to define the peculiarities of skeletal muscular tissue more precisely.

Animals↗

[Ultrastructure of the striated muscle tissue of the iris of birds].

Heteromorphism of the contractile elements of the iris muscular tissue in chick embryos and in chickens has been studied by means of electron microscopical investigation. The leading contractile tissue of the iris is the striated muscular tissue, which is formed as a cellular-simplastic system with its own cambium-myosatellitocytes. Some cells, containing myofilaments in their cytoplasm, are related to myofibroblastic and smooth muscle differons, which functions remain to be studied. A hypothesis is proposed on existence of two sources for development of the iris muscular elements. The first-stem cells for the striated muscular tissue; at early stages of embryonal development they are included into composition of ectomesenchyme of the neural crest and migrate into the area of the muscle anlages. The second-cells migrating from the ocular cup margins and developing into the smooth myocytes of the iris.

Animals↗