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T A Iurimiaé A A Viru K M Karelson M E Lintsi T A Smirnova 《Fiziologicheski? zhurnal》1989,35(1):78-82
The effect of triathlon (3.8 km swimming, 180 km biking, 42 km running) and of its short variant (1.5 km swimming, 42 km biking, 14 km running) was studied in 7 and 14 well-trained men, respectively. The level of plasma glucose, total cholesterol, HDL, LDL did not change significantly during the competition. FFA concentration increased significantly (by 439 and 61%, respectively). Triglycerides concentration decreased during the prolonged variant. Both variants of triathlon caused a pronounced rise in the cortisol level and moderate increase in somatotropin and progesterone levels. Testosterone concentration increased during a short variant and decreased during a prolonged one. Insulin and C-peptide levels decreased. All those changes in hormones concentration are consistent with an increased lipolytic activity and, may be, with increased glycolytic activity (maintenance of the normal glucose concentration in blood). The rise in the aldosterone level reflects the homeostatic activity in maintaining electrolyte balance. 相似文献
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Viral vectors have a wide variety of applications ranging from fundamental studies of viruses to therapeutics. Recombinant viral vectors are usually constructed using methods of reverse genetics to obtain the genetic material of the viral vector. The physicochemical properties of DNA and RNA make them unable to access cells by themselves, and they require assistance to achieve intracellular delivery. Non-viral delivery vectors can be used for this purpose if they enable efficient intracellular delivery without interfering with the viral life cycle. In this report, we utilize Semliki Forest virus (genus alphavirus) based RNA and DNA vectors to study the transfection efficiency of the non-viral cell-penetrating peptide-based delivery vector PepFect6 in comparison with that of the cationic liposome-based Lipofectamine 2000, and assess their impact on viral replication. The optimal conditions for transfection were determined for both reagents. These results demonstrate, for the first time, the ability of PepFect6 to transport large (13-19 kbp) constructs across the cell membrane. Curiously, DNA molecules delivered using the PepFect6 reagent were found to be transported to the cell nucleus approximately 1.5 hours later than DNA molecules delivered using the Lipofectamine 2000 reagent. Finally, although both PepFect6 and Lipofectamine 2000 reagents can be used for alphavirus research, PepFect6 is preferred because it does not induce changes in the normal cellular phenotype and it does not affect the normal replication-infection cycle of viruses in previously transfected cells. 相似文献
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Atko Viru 《Journal of applied physiology》2002,92(4):1378-1382
In Russia, the free development of scientific ideas was suppressed in 1950 as a result of the actions of the Joint Session of the Academy of Sciences and the Academy of Medical Sciences of the USSR. Hans Selye's theory on the general adaptation syndrome was considered unscientific. From 1956 to 1958, Pjotr Anokhin and Pjotr Gorizontov presented definitive arguments for having the theory accepted by scientists while the significance of hormones in adaptation became a topic of endocrine studies (Boris Aleshin, Igor Eskin, Vassily Komissarenko, Samuel Leites, and Michael Kolpakov). Later, Felius Meerson made essential contributions to the adaptive significance of protein synthesis and stress-limiting systems. The area of exercise physiology dealing with acute and chronic adaptation to strong physiological stressors was founded by Leon Orbeli and developed by Aleksei Krestovnikov. Significant contributors to this area were Vladimir Farfel, Nikolai Yakovlev, and Nikolai Zimkin. Although the majority of their publications have remained unknown outside of Russia, it is interesting that many of their results have been "rediscovered" by others. Yakovlev also deserves recognition because he was among the founders of contemporary exercise biochemistry and because his research has provided the foundation for current investigations. Several generations of young scientists have been inspired by the above-mentioned Russian scientists. Today, however, the research activities of scientists are no longer limited by political pressures but by financial resources instead. 相似文献
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A 3 week training period in running restored the maximal swimming time of adrenalectomized rats to the level of intact untrained rats, but had no influence on the maximal running time and hepatic glycogen reserve. The cardiac hypertrophy and the augmentation of the Mg2+-activated ATPase activity of myocardium in adrenalectomized rats were more pronounced than in intact animals. It is concluded that the deficiency of adrenocortical hormones does not exclude all the adaptive alterations during training, although it makes the complete adaptation and normal increase of the working capacity impossible. 相似文献
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Camilla Parzanini Michael T. Arts Mehis Rohtla Janet Koprivnikar Michael Power Anne Berit Skiftesvik Howard I. Browman Dino Milotic Caroline M. F. Durif 《Journal of fish biology》2021,99(3):1110-1124
Lipids, particularly fatty acids (FAs), are major sources of energy and nutrients in aquatic ecosystems and play key roles during vertebrate development. The European eel Anguilla anguilla goes through major biochemical and physiological changes throughout its lifecycle as it inhabits sea- (SW), and/or brackish- (BW) and/or freshwater (FW) habitats. With the ultimate goal being to understand the reasons for eels adopting a certain life history strategy (FW or SW residency vs. ‘habitat shifting’), we explored differences in lipid content and FA composition of muscle, liver and eyes from eels collected across Norwegian SW, BW and FW habitats, and at different lifecycle stages (yellow to silver). FW and SW eels had a higher lipid content overall compared to BW eels, reflecting differences in food availability and life history strategies. SW eels had higher proportions of certain monounsaturated FAs (MUFAs; 18:1n-9, 20:1n-9), and of the essential polyunsaturated FAs 20:5n-3 (eicosapentaenoic acid, EPA) and 22:6n-3 (docosahexaenoic acid) than FW eels, reflecting a marine-based diet. In contrast, the muscle of FW eels had higher proportions of 18:3n-3, 18:2n-6 and 20:4n-6 (arachidonic acid), as is typical of FW organisms. MUFA proportions increased in later stage eels, consistent with the hypothesis that the eels accumulate energy stores prior to migration. In addition, the decrease of EPA with advancing stage may be associated with the critical role that this FA plays in eel sexual development. Lipid and FA information provided further understanding of the habitat use and overall ecology of this critically endangered species. 相似文献
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Carole D. Mitnick Molly F. Franke Michael L. Rich Felix A. Alcantara Viru Sasha C. Appleton Sidney S. Atwood Jaime N. Bayona Cesar A. Bonilla Katiuska Chalco Hamish S. F. Fraser Jennifer J. Furin Dalia Guerra Rocio M. Hurtado Keith Joseph Karim Llaro Lorena Mestanza Joia S. Mukherjee Maribel Mu?oz Eda Palacios Epifanio Sanchez Kwonjune J. Seung Sonya S. Shin Alexander Sloutsky Arielle W. Tolman Mercedes C. Becerra 《PloS one》2013,8(3)