• Journal of Life Science
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• v.22 no.3
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• pp.312-317
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• 2012

The time-dependent effects of highly intensive exercise on the hematological properties of leukocytes, as well as $CD4^+$ and $CD8^+$ level changes as T-lymphocyte activation subsets and the cell death of lymphocytes in rats were studied in this research. Twenty, 60, and 120 min of highly intensive exercise was performed daily for 8 weeks. Total leukocyte counts in the blood of rats exercising for 20 min were elevated; they then decreased to less than the level of the control group up to 120 min. The patterns of lymphocyte level changes were directly influenced by exercise duration and the extents of alteration were similar to the total leukocytes counts. The levels of $CD4^+$ and $CD8^+$ in the blood of the exercising rats were not statistically different even when the exercise was continued for 120 min; thus, the exercise did not affect T-lymphocyte activation. Early- and late-stage lymphocyte apoptosis was not affected by the length of exercise, except that late-phase apoptosis was slightly increased at 120 min, suggesting that aging processes for lymphocyte apoptosis might be stimulated at that time. As the exercise time became longer, stimulated necrosis of lymphocytes was observed, so damage in lymphocytes and a potential loss of immunity might be presumed. The current observation suggests that long-term, highly intensive exercise might result in a loss of immunity that could be due to the damage of lymphocytes in terms of both their numbers and inflammation-related functions. The results suggest that under highly intensive exercise conditions, more than 20 min of exercise should not be suggested for health care purposes.

• The Korean Journal of Ecology
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• v.24 no.3
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• pp.191-202
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• 2001

Human being has extensively invaded, occupied, and used the natural environment as a consequence of the advance of civilization. Mankind has increasingly modified the environment for his own benefit. Such modification has not only caused the extinction of many other species but also, caused human being himself to confront to serious environmental problems. The recognition of this fact by human is expressed in the establishment and development of restoration ecology. This new study fold is, in fact, an "Eco-technology" directed towards healing of damages to the environment. The goal is to reestablish processes and functions in a damaged site, imitating the way of healing works that an integral natural system carries out. Ecological restoration uses different treatments and approaches according to extents of the existing damage and to the specific goal to be achieved. An ecological diagnosis is, therefore, required prior to restoration practice. The cost and efforts to achieve a proposed goal can be significantly reduced when a restoration plan is formulated upon the results of well-conducted ecological diagnosis. Under such perspectives, restoration ecology is a practical science, which aims to solve the problems of the real world based on the existing ecological principle. Furthermore, restoration ecology offers opportunities to test the ecological concepts and theories obtained by means of the former ecological studies. Human being exploited natural environment excessively for his comfort on one hand but damaged it inevitably on the other hand. Such intensive resource utilization and continuous environmental damaging will extend into the future and ultimately jeopardize the survival of humankind if no prompt action is taken. In the present situation, we must not continue such lives without any preparation. We have to cope with the environmental crises approaching near us by pursuing the ecological restoration that reduce the unnecessary use, recruit the deficient part, and strengthen the weak portion in our environment. Restoration ecology could be recognized as the ecology for the future in such viewpoints.