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Biomedical subjects

A A Karpenko

Publications and source records attributed to A A Karpenko.

16 recordsLinked to original sources
PubMed2000

Isolation and partial characterization of myogenic cells from mussel larvae in vitro.

The main finding of the present study is the discovery of the possibility of a morphofunctional myogenic differentiation of larval mussel cells in vitro. The shape and extensive cytoskeletal network of the cultured contracting cells mimic largely those of smooth muscle cells in vivo. However, the behavior and protein composition of these cells are not completely identical with those of smooth muscle cells. Contracting mussel cells in vitro, as well as differentiated smooth muscles, demonstrate both phasic and tonic contractions. The paramyosin to myosin ratio in the cultured mussel cells is far less than that in the muscles of veliger larvae and adult mussels. We have found the protein carpets with various adhesive characteristics determine different development pathways. Myogenic differentiation is only observed in spreading cells. Non-spreading adherent cells plated on collagen carpet show high synthetic activity but the commitment of contractile phenotype is inhibited. Our results confirm that the myogenic program established in early embryogenesis of molluscs can be realized during the cultivation of cells from premyogenic larval stages.

Actins↗
PubMed1997

[Initial experience in the diagnosis of thrombophilia due to activated protein C resistance].

The authors describe the first in Russia cases of thrombophilia caused by factor Va resistance to activated protein C. This abnormality was diagnosed in 6 of 25 patients (24%) with recurrent early thrombosis. The diagnosis was conducted according to a modified method implying the addition of protac (activator of protein C) to normal platelet poor plasma (PPP) free of factor V containing 100% of protein C. Protac dose was adjusted to increase the activated partial thromboplastin time (APTT) 2.4-2.8-fold in mixing PPP of the examinee with plasma containing activated protein C. The indices were estimated indicative of insufficient prolongation of APTT in response to activated protein C. Of 6 patients, 2 had apparent and 4 strong resistance to activated protein C. Treatment policy in this variant of thrombophilia is discussed.

Adolescent↗
PubMed1996

Effect of inducers of lipid peroxidation on the behavior of ciliated epithelial cells.

Television microscope and original image treatment system were used for monitoring and recording the ciliary activity (beat frequency) of gill ciliated epithelia of the mussel Mytilus edulis (Bivalvia) and of the rat tracheal ciliated epithelia in response to the following prooxidants: H2O2, Fe+2, Fe+2 + ascorbic acid and NADP-H + ADP + Fe+2. Mussel ciliated cells proved to be more sensitive to the influence of the prooxidants than rat cells. The reactions of ciliated epithelial cells of mollusks and rats to the inducers of lipid peroxidation were not similar to behavioral responses of these cells under the action of low-dose ionizing radiation.

Animals↗
PubMed1996

[Mucociliary function in acute pneumonia].

Radioaerosol method was employed to follow up mucociliary transport (MT) efficacy in 97 patients with acute pneumonia (AP). The most pronounced suppression of MT was found in repeated and lingering AP. If causative agents were represented by adenoviruses, streptococci and influenza bacillus suppression of MT appeared more noticeable. Correlations of MT with pulmonary ventilation support the role of mucociliary insufficiency in genesis of bronchial obstruction in AP. The majority of the convalescents fail to achieve complete recovery of MT.

Acute Disease↗
PubMed1995

[Intravascular prevention of pulmonary thromboembolism (cava filter volan). 2].

The article describes a cava filter "volan" suggested by the authors and the methods of its implantation through the subclavian or femoral vein for primary or secondary prevention of thromboembolism of the pulmonary arteries. The simplicity of the device, universality in size and character of its use for temporary and permanent percutaneous implantation, and the possibility of its application in peripheral nonspecialized therapeutic institutions are noted. The experience in its use in 93 patients with phlebothrombosis of the lower limbs and thromboembolism of the pulmonary arteries is discussed. In 38 patients with temporary implantation the filter was removed in 2 weeks to 6 months. The high effectiveness of the device and the method of its application is noted and wider indications for its use are recommended.

Femoral Vein↗
PubMed1993

[Intravascular thrombolytic therapy in the treatment of acute thrombophlebitis of the lower extremities and pelvis (Report 1)].

A new method of thrombolytic therapy is described and substantiated. It consists in percutaneous catheterization of the popliteal vein with a system of paired catheters with the inner one being advanced during infusion of the thrombolytics in the thickness of the thrombus along the length of the proximal segments of the main vein. Phlebographic control is accomplished through the outer, short catheter. The preparations of streptokinase awelysin and celiase were used. The new method of treatment was applied in 27 cases. Comparison with groups of patients treated by other methods of systemic and regional thrombolytic therapy showed that the efficacy of the suggested method was higher. Good late results were found in 72% of patients of the main group. A necessary condition of the applied method is prevention of thromboembolism of the pulmonary arteries by temporary implantation of a cava-filter into the inferior vena cava.

Acute Disease↗
PubMed1993

[The clinical characteristics, complications and therapeutic problems of protein C deficiency].

Examination was performed of 20 patients from 15 families with heterozygous deficiency of protein C (27-62% against the mean standard). Recurrent thromboses were seen in 17 of them. Thromboses of the lower veins, pulmonary artery thromboembolism, thromboses of the surface veins, those of cerebral vessels, myocardial infarction, of renal and mesenterial vessels were registered in 15, 5, 4, 3, 3, 1 and 1 patients, respectively. There was a tendency to recurrent thrombosis during pregnancy with high risk of spontaneous or induced abortions. The highest effect was produced with low-molecular heparin combined with transfusions of recently frozen plasma and introduction of disaggregating agents. Anabolic hormones were used to prevent thrombosis. The data are provided on a 4-fold increase in the prevalence of protein C deficiency in polythrombotic patients living in the West Siberia vs. deficiency of antithrombin III.

Adolescent↗
PubMed1993

Effect of very low doses of gamma radiation on motility of gill ciliated epithelia of Mytilus edulis.

An investigation of the effect of gamma radiation on the motility of mussel gill ciliated epithelia was conducted using dose rates of 0.9 and 2 mGy/h. There was a definite decrease in the beat frequency and a distortion of the metachronal wave by 20-30 min after irradiation with 0.9 Gy/h. With a total dose of 0.9 mGy, the beat frequency was decreased 2- to 2.5-fold. In the period after irradiation a restoration of the metachronal wave was observed, but the beat frequency was about 50% of the control level. Gamma irradiation completely stopped the beating of the cilia when given at a dose rate of 2 mGy/h.

Animals↗
PubMed1990

[Assessment of the functional status of the ciliary apparatus of the respiratory pathways during pathology of the respiratory organs].

Using a television system, the function of the ciliary system of the bronchial ciliated epithelium in patients with acute pneumonia, chronic and acute bronchitis and in healthy subjects was studied. Diagnostic signs of the ciliary dysfunction in respiratory pathology were defined, i.e. lower ciliary rate, their shorter amplitude, local and general dysmetachronia, etc. The influence of temperature and medium pH changes on the ciliated epithelium's motor activity in normal and pathologic cases was analysed.

Adult↗
PubMed1989

[A method for recording the motor activity of the cilia of ciliated epithelium].

The article deals with the television system which registers the lash movements on the screen of TV monitor. The natural moving activity (frequency of whipping) and lashes' activity after the action of different concentration of surface-active substance Triton-H-305 and potassium chloride were investigated on the example of the epithelium of two-folding molluscum. It observes the following type of lashes reaction: unbroken (continuous) whipping, mechanically induced stopping of whipping ("stop effect"), spontaneous "stop effect", starting of whipping due to mechanic action-specific "sorting" lashes (the last are described for the first time).

Animals↗
PubMedDate not supplied

[Myogenic differentiation of Mytilus larval cells in vitro].

A myogenic differentiation program can be realized during the cultivation of Mytilus trossulus cells derived from larvae in premyogenic developmental stages. About 10-15% of cells in such cultures showed that they are capable of contracting actively. The shape of such cells and the high concentration of actin microfilaments indicate a similarity with smooth muscle cells. However, the pattern of contractile activity and the protein composition of these cells differ significantly from the corresponding characteristics of differentiated smooth muscle cells. The proportion between the main proteins of the thick fiber, paramyosin, and myosin in cultivated cells is far lower than in the muscles of larvae or adult molluscs. We also found that substrates with different adhesional characteristics may determine cell development towards one or the other phenotype. Cells attached to the collagen substrate, but not spread on it, had high proliferative potential; the collagen substrate, however, inhibited myogenic differentiation.

Animals↗
PubMedDate not supplied

[The ciliated epithelium of the rat trachea is sensitive to gamma-irradiation in very low doses].

As early as 5-7 min after the start of exposure of tissue preparations from rat trachea ciliated epithelium to gamma-radiation at a dose rate of 19 mGy/h, the ciliary motion rate increased periodically. The phenomenon of increasing the ciliary motion occurred more frequently in time; the intervals between two frequency drops became longer and the mean frequency level higher. The reverse sequence of the events was observed during the postirradiation period. The same regularities, but less expressed, were observed after irradiation at a dose rate of 1.8 mGy/h.

Animals↗