Objective To determine the in vitro possible clastogenic and cytotoxic activities of Ulva rigida crude extracts （URE）, and identify their antigenotoxic and protective effects on chemotherapeutic agent mitomycine-C ...Objective To determine the in vitro possible clastogenic and cytotoxic activities of Ulva rigida crude extracts （URE）, and identify their antigenotoxic and protective effects on chemotherapeutic agent mitomycine-C （MMC）. Methods Anti-clastogenic and anti-genotoxic activities of Ulva rigida crude extracts （URE） were studied using chromosome aberration （CA）, sister chromatid exchange （SCE）, and micronuclei （MN） tests in human lymphocytes cultured in vitro. Results The chromosome aberration, sister chromatid exchange or micronuclei tests showed that URE at concentrations of 10, 20, and 40 lag/mL had no clastogenic activity in human lymphocyte cell culture. Three doses of URE significantly decreased the number of chromosomal aberrations and the frequencies of SCE and MN when compared with the culture treated with MMC （P〈0.0001）. Conclusion Although URE itself is not a clastogenic or cytotoxic substance, it possesses strong antigenotoxic, anti-clastogenic, and protective effects on MMC in vitro.展开更多
The Pine Barrens in New York State are dominated by pitch pine(Pinus ridgida) and scrub oaks(Quercus ilicifolia and Q. prinoides). With fire suppression over the last 90 years or so, P. rigida regeneration has become ...The Pine Barrens in New York State are dominated by pitch pine(Pinus ridgida) and scrub oaks(Quercus ilicifolia and Q. prinoides). With fire suppression over the last 90 years or so, P. rigida regeneration has become sparse, even in areas set aside to preserve this type of vegetation. We evaluated the effects of fire and an alternative disturbance(mechanical removal of vegetation)for increasing P. rigida regeneration in the Albany Pine Bush Preserve in eastern New York State. By comparing cover, diameter and height of P. rigida, Q. ilicifolia, Q.prinoides, and Vaccinium spp.(blueberry) growing on the sites with a known fire history, we documented structural and compositional changes in the vegetation since its establishment. We also compared sites on which Quercus sprouts were controlled through mechanical removal. In the years following a disturbance, height and cover of Q. ilicifolia increased continuously and the species became increasingly competitive. Both the density of P. rigida seedlings and Vaccinium cover decreased significantly as the diameter and height of Quercus increased. Our results confirmed that the dominance by P. rigida could be attributed to periodic fires at intervals of 20–25 years. We conclude that removing Q. ilicifolia can favor P. rigida dominance on the barren without fire by releasing pine seedlings from competition.展开更多
An investigation was conducted using ^(45)Ca as a radioactive tracer to evaluate calcium antagonistic effects of several extracts from Bambusa Rigida in living rats.The relationship between the flavonoid and saccharid...An investigation was conducted using ^(45)Ca as a radioactive tracer to evaluate calcium antagonistic effects of several extracts from Bambusa Rigida in living rats.The relationship between the flavonoid and saccharide contents of Bambusa Rigida and calcium antagonistic effects were also analyzed.The protective effects of the alkali extracts of Bambusa Rigida on myocardial ischemia were investigated in living rats.The results indicated that the alkali extracts of Bambusa Rigida had a prominent influence on Ca^(2+) influx and efflux in the isolated rat aorta and heart,as they could obviously block ^(45)Ca entering into cells and stimulate efflux of intracellular Ca^(2+).Moreover,the alkali extracts of Bambusa Rigida had favorable protective effects on myocardial ischemia induced either by isoproterenoi injection (ISO) or by the ligation of coronary artery.These results implied that the Bambusa Rigida had attractive potential for the treatment of heart,cerebrovascular and other diseases.However,the conclusion that whether the flavonoid or saccharide in Bambusa Rigida affected the calcium antagonistic effects and Ca^(2+) channels or not was hard to make within the results of the investigation.展开更多
基金supported by a grant from the Scientific and Technical Research Council of Turkey, Ankara (TüBiTAK, 107T279 (TBAG/HD-304).
文摘Objective To determine the in vitro possible clastogenic and cytotoxic activities of Ulva rigida crude extracts （URE）, and identify their antigenotoxic and protective effects on chemotherapeutic agent mitomycine-C （MMC）. Methods Anti-clastogenic and anti-genotoxic activities of Ulva rigida crude extracts （URE） were studied using chromosome aberration （CA）, sister chromatid exchange （SCE）, and micronuclei （MN） tests in human lymphocytes cultured in vitro. Results The chromosome aberration, sister chromatid exchange or micronuclei tests showed that URE at concentrations of 10, 20, and 40 lag/mL had no clastogenic activity in human lymphocyte cell culture. Three doses of URE significantly decreased the number of chromosomal aberrations and the frequencies of SCE and MN when compared with the culture treated with MMC （P〈0.0001）. Conclusion Although URE itself is not a clastogenic or cytotoxic substance, it possesses strong antigenotoxic, anti-clastogenic, and protective effects on MMC in vitro.
文摘The Pine Barrens in New York State are dominated by pitch pine(Pinus ridgida) and scrub oaks(Quercus ilicifolia and Q. prinoides). With fire suppression over the last 90 years or so, P. rigida regeneration has become sparse, even in areas set aside to preserve this type of vegetation. We evaluated the effects of fire and an alternative disturbance(mechanical removal of vegetation)for increasing P. rigida regeneration in the Albany Pine Bush Preserve in eastern New York State. By comparing cover, diameter and height of P. rigida, Q. ilicifolia, Q.prinoides, and Vaccinium spp.(blueberry) growing on the sites with a known fire history, we documented structural and compositional changes in the vegetation since its establishment. We also compared sites on which Quercus sprouts were controlled through mechanical removal. In the years following a disturbance, height and cover of Q. ilicifolia increased continuously and the species became increasingly competitive. Both the density of P. rigida seedlings and Vaccinium cover decreased significantly as the diameter and height of Quercus increased. Our results confirmed that the dominance by P. rigida could be attributed to periodic fires at intervals of 20–25 years. We conclude that removing Q. ilicifolia can favor P. rigida dominance on the barren without fire by releasing pine seedlings from competition.
基金National Natural Science Foundation of China (Grant No.10175044).
文摘An investigation was conducted using ^(45)Ca as a radioactive tracer to evaluate calcium antagonistic effects of several extracts from Bambusa Rigida in living rats.The relationship between the flavonoid and saccharide contents of Bambusa Rigida and calcium antagonistic effects were also analyzed.The protective effects of the alkali extracts of Bambusa Rigida on myocardial ischemia were investigated in living rats.The results indicated that the alkali extracts of Bambusa Rigida had a prominent influence on Ca^(2+) influx and efflux in the isolated rat aorta and heart,as they could obviously block ^(45)Ca entering into cells and stimulate efflux of intracellular Ca^(2+).Moreover,the alkali extracts of Bambusa Rigida had favorable protective effects on myocardial ischemia induced either by isoproterenoi injection (ISO) or by the ligation of coronary artery.These results implied that the Bambusa Rigida had attractive potential for the treatment of heart,cerebrovascular and other diseases.However,the conclusion that whether the flavonoid or saccharide in Bambusa Rigida affected the calcium antagonistic effects and Ca^(2+) channels or not was hard to make within the results of the investigation.
