The Experts below are selected from a list of 90 Experts worldwide ranked by ideXlab platform
Andrei G Pakhomov - One of the best experts on this subject based on the ideXlab platform.
-
Electroporation-induced electrosensitization.
PloS one, 2011Co-Authors: Olga N Pakhomova, Betsy W Gregory, Vera A Khorokhorina, Angela M Bowman, Shu Xiao, Andrei G PakhomovAbstract:Electroporation is a method of disrupting the integrity of cell membrane by electric pulses (EPs). Electrical modeling is widely employed to explain and study electroporation, but even most advanced models show limited predictive power. No studies have accounted for the biological consequences of electroporation as a factor that alters the cell's susceptibility to forthcoming EPs. We focused first on the role of EP rate for membrane permeabilization and lethal effects in mammalian cells. The rate was varied from 0.001 to 2,000 Hz while keeping other parameters constant (2 to 3,750 pulses of 60-ns to 9-µs duration, 1.8 to 13.3 kV/cm). The efficiency of all EP treatments was minimal at high rates and started to increase gradually when the rate decreased below a certain value. Although this value ranged widely (0.1-500 Hz), it always corresponded to the overall treatment duration near 10 s. We further found that longer exposures were more efficient irrespective of the EP rate, and that splitting a high-rate EP train in two fractions with 1-5 min delay enhanced the effects severalfold. For varied experimental conditions, EPs triggered a delayed and gradual sensitization to EPs. When a portion of a multi-pulse exposure was delivered to already sensitized cells, the overall effect markedly increased. Because of the sensitization, the lethality in EP-treated cells could be increased from 0 to 90% simply by increasing the exposure duration, or the exposure dose could be reduced twofold without reducing the effect. Many applications of electroporation can benefit from accounting for sensitization, by organizing the exposure either to maximize sensitization (e.g., for sterilization) or, for other applications, to completely or partially avoid it. In particular, harmful side effects of electroporation-based therapies (electrochemotherapy, gene therapies, tumor ablation) include convulsions, pain, Heart Fibrillation, and thermal damage. Sensitization can potentially be employed to reduce these side effects while preserving or increasing therapeutic efficiency.
V. A. Isaev - One of the best experts on this subject based on the ideXlab platform.
-
Correction of disorders of cardiac electric stability in post-infarction cardiosclerosis using a diet enriched with polyunsaturated fatty acids
Biulleten' eksperimental'noi biologii i meditsiny, 1993Co-Authors: Fu Sts, V. A. IsaevAbstract:In a 14-20 days after feeding of rats with "eikonole" (cod-liver oil, deduced from skeletal muscle and enriched by eicosapentaenic and docosahexaenic fatty acids). Myocardial infarction by Selie has been induced and in a 30 days of the same feeding, contractile function and Heart electrical stability in situ have been investigated. Eikonole increased Heart Fibrillation threshold by 50%, decreased the frequency of spontaneous extrasystole in 3 times and ectopic activation (extrasystole), induced by n. vagus stimulation, in 2.5 times. Eikonole increased the intensity of structures' functioning in the state of relative physiological rest, but did not influence essentially on pressure and the velocity of myocardial contraction and weakening.
Wen-qi Hou - One of the best experts on this subject based on the ideXlab platform.
-
Endurance exercise prevents high-fat-diet induced Heart and mobility premature aging and dsir 2 expression decline in aging Drosophila
Oncotarget, 2017Co-Authors: Deng-tai Wen, Lan Zheng, Fan Yang, Wen-qi HouAbstract:High-Fat-Diet (HFD)-induced obesity is a major contributor to Heart and mobility premature aging and mortality in both Drosophila and humans. The dSir2 genes are closely related to aging, but there are few directed reports showing that whether HFD could inhibit the expression dSir2 genes. Endurance exercise can prevent fat accumulation and reverse HFD-induced cardiac dysfunction. Endurance also delays age-relate functional decline. It is unclear whether lifetime endurance exercise can combat lifetime HFD-induced Heart and mobility premature aging, and relieve the harmful HFD-induced influence on the dSir2 gene and lifespan yet. In this study, flies are fed a HFD and trained from when they are 1 week old until they are 5 weeks old. Then, triacylglycerol levels, climbing index, cardiac function, lifespan, and dSir2 mRNA expressions are measured. We show that endurance exercise improves climbing capacity, cardiac contraction, and dSir2 expression, and it reduces body and Heart triacylglycerol levels, Heart Fibrillation, and mortality in both HFD and aging flies. So, lifelong endurance exercise delays HFD-induced accelerated age-related locomotor impairment, cardiac dysfunction, death, and dSir2 expression decline, and prevents HFD-induced premature aging in Drosophila.
Olga N Pakhomova - One of the best experts on this subject based on the ideXlab platform.
-
Electroporation-induced electrosensitization.
PloS one, 2011Co-Authors: Olga N Pakhomova, Betsy W Gregory, Vera A Khorokhorina, Angela M Bowman, Shu Xiao, Andrei G PakhomovAbstract:Electroporation is a method of disrupting the integrity of cell membrane by electric pulses (EPs). Electrical modeling is widely employed to explain and study electroporation, but even most advanced models show limited predictive power. No studies have accounted for the biological consequences of electroporation as a factor that alters the cell's susceptibility to forthcoming EPs. We focused first on the role of EP rate for membrane permeabilization and lethal effects in mammalian cells. The rate was varied from 0.001 to 2,000 Hz while keeping other parameters constant (2 to 3,750 pulses of 60-ns to 9-µs duration, 1.8 to 13.3 kV/cm). The efficiency of all EP treatments was minimal at high rates and started to increase gradually when the rate decreased below a certain value. Although this value ranged widely (0.1-500 Hz), it always corresponded to the overall treatment duration near 10 s. We further found that longer exposures were more efficient irrespective of the EP rate, and that splitting a high-rate EP train in two fractions with 1-5 min delay enhanced the effects severalfold. For varied experimental conditions, EPs triggered a delayed and gradual sensitization to EPs. When a portion of a multi-pulse exposure was delivered to already sensitized cells, the overall effect markedly increased. Because of the sensitization, the lethality in EP-treated cells could be increased from 0 to 90% simply by increasing the exposure duration, or the exposure dose could be reduced twofold without reducing the effect. Many applications of electroporation can benefit from accounting for sensitization, by organizing the exposure either to maximize sensitization (e.g., for sterilization) or, for other applications, to completely or partially avoid it. In particular, harmful side effects of electroporation-based therapies (electrochemotherapy, gene therapies, tumor ablation) include convulsions, pain, Heart Fibrillation, and thermal damage. Sensitization can potentially be employed to reduce these side effects while preserving or increasing therapeutic efficiency.
Fu Sts - One of the best experts on this subject based on the ideXlab platform.
-
Correction of disorders of cardiac electric stability in post-infarction cardiosclerosis using a diet enriched with polyunsaturated fatty acids
Biulleten' eksperimental'noi biologii i meditsiny, 1993Co-Authors: Fu Sts, V. A. IsaevAbstract:In a 14-20 days after feeding of rats with "eikonole" (cod-liver oil, deduced from skeletal muscle and enriched by eicosapentaenic and docosahexaenic fatty acids). Myocardial infarction by Selie has been induced and in a 30 days of the same feeding, contractile function and Heart electrical stability in situ have been investigated. Eikonole increased Heart Fibrillation threshold by 50%, decreased the frequency of spontaneous extrasystole in 3 times and ectopic activation (extrasystole), induced by n. vagus stimulation, in 2.5 times. Eikonole increased the intensity of structures' functioning in the state of relative physiological rest, but did not influence essentially on pressure and the velocity of myocardial contraction and weakening.
