From Jan</span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;"> 2013 to Nov</span><span style="font-family:Verdana;">.<...From Jan</span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;"> 2013 to Nov</span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;"> 2018, we carried out the investigation on vegetation studies in the ecological monitoring programs, Shenzhen</span><span style="font-family:Verdana;"> and</span><span style="font-family:""><span style="font-family:Verdana;"> totally researched 170 plant communities of mountain areas etc., </span><span style="font-family:Verdana;">few areas of street regions and parks etc., for communities’ structural characteristics and plant diversity. We comparatively analyzed natural forests, semi-natural forest and artificial forest composition and structural characters and family, genus and species diversity level and the main affected factors. We also researched and analyzed these communities’ structural characteristics and pant diversity, </span><span style="font-family:Verdana;">comparatively analyzed natural forests, semi-natural forest and artificial forest composition and structural characters and family, genus and species diversity level, the main affected factors;researched and analyzed the relationship between plant community structure characteristics with the absorbing ability to PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;"> pollutants. The result showed that the structure and plant diversity of natural </span><span style="font-family:Verdana;">forest </span></span><span style="font-family:Verdana;">were </span><span style="font-family:Verdana;">obviously better than</span><span style="font-family:Verdana;"> artificial disturbed forest or artificial forest, the semi-natural forest w</span><span style="font-family:Verdana;">as</span><span style="font-family:Verdana;"> the middle level of the forests, In the indices of height, DBH, coverage and crow width etc. of tree layer, natural forests and semi-natural forests were obvious higher than that of artificial disturbed forest or artificial forest;in some forests of artificial disturbed forest or artificial forest, though their richness indices of family and genus were a slightly higher, but this contribution was majorly due to herb layer plants, and some shrub layer plants. Analyz</span><span style="font-family:Verdana;">ing</span><span style="font-family:Verdana;"> three kinds of communities, the number of tree layer species of natural forest was</span><span style="font-family:Verdana;"> the </span><span style="font-family:""><span style="font-family:Verdana;">largest, and their every </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-diversity index value was </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">highest;these characteristics values of semi-natural forest were second, artificial disturbed forests or artificial forests were </span><span style="font-family:Verdana;">the </span><span style="font-family:""><span style="font-family:Verdana;">lowest;in shrub layer, and herb layer, few </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-diversity indices of artificial disturbed forest or artificial forest were </span><span style="font-family:Verdana;">a slightly higher than that of some natural forests, but the integral values of the diversity indices of natural forest and semi-natural forest were obvious</span></span><span style="font-family:Verdana;">ly</span><span style="font-family:Verdana;"> higher than the former. The research showed that in the artificial disturbed forest or artificial forest, because there have some little scale clearing area</span><span style="font-family:Verdana;">s</span><span style="font-family:""><span style="font-family:Verdana;">, so some pioneer plant species could enter the community and formed a temporarily </span><span style="font-family:Verdana;">increase of species diversity, however</span></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> these species major </span><span style="font-family:Verdana;">were</span><span style="font-family:Verdana;"> some shrub and herb plants;but tree layer possessed obvious</span><span style="font-family:Verdana;">ly</span><span style="font-family:Verdana;"> more, even surpass</span><span style="font-family:Verdana;">ed</span><span style="font-family:Verdana;"> several ten times biomass than shrub and herb layers</span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;"> Therefore</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> the respect</span><span style="font-family:Verdana;">s</span><span style="font-family:""><span style="font-family:Verdana;"> of maintain ecosystem stability and other</span><span style="font-family:Verdana;"> ecological efficient have </span><span style="font-family:Verdana;">major and dominated position and so on;and then this community can </span></span><span style="font-family:Verdana;">be </span><span style="font-family:Verdana;">natural recovery and succession, those forementioned new entire plants shall withdraw from the community and are replaced by the original plants of the community;but this process has already caused the ecological efficient loss and ecosystem unstable. Above research results are better evidence and theory reference to the argument problems on that </span><span style="font-family:Verdana;">are</span><span style="font-family:""><span style="font-family:Verdana;"> natural forest and natural restoration forest biodiversity higher? or is artificial forest biodiversity higher? and or is more artificial disturbed forest higher?</span><span style="font-family:Verdana;"> Our researches showed that used random investigation method set quadrats, and combined typical investigation method, the structural indices in the all layer of community and all diversity indices of tree, shrub and herb layers and the integral values </span></span><span style="font-family:Verdana;">were</span><span style="font-family:""><span style="font-family:Verdana;"> similar, same or usually these indices in the community which set 600 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">, 800 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> total quatrat area were higher (</span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-diversity) than that of more than 3000 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">, 4000 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> or 7000 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">, even more than 17,000 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> total qua</span></span><span style="font-family:Verdana;">d</span><span style="font-family:Verdana;">rat area of communities. These lot</span><span style="font-family:Verdana;">s</span><span style="font-family:""><span style="font-family:Verdana;"> of researches further proved that according to minimum area method for vegetation survey, in subtropical region, using random investigation method combined with typical investigation set 400 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> or 400 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> - 500 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> total qua</span></span><span style="font-family:Verdana;">d</span><span style="font-family:""><span展开更多
The anticancer therapies with the joint treatment of a histone deacetylase(HDAC) inhibitor and a DNA-damaging approach are actively under clinical investigations, but the underlying mechanism is unclear. Histone homeo...The anticancer therapies with the joint treatment of a histone deacetylase(HDAC) inhibitor and a DNA-damaging approach are actively under clinical investigations, but the underlying mechanism is unclear. Histone homeostasis is critical to genome stability, transcriptional accuracy, DNA repair process, senescence, and survival. We have previously demonstrated that the HDAC inhibitor, trichostatin A(TSA), could promote the degradation of the core histones induced by γ-radiation or the DNAalkylating agent methyl methanesulfonate(MMS) in non-cancer cells, including mouse spermatocyte and embryonic fibroblast cell lines. In this study, we found that the joint treatment by TSA and MMS induced the death of the cultured cancer cells with an additive effect, but induced degradation of the core histones synergistically in these cells. We then analyzed various combinations of other HDAC inhibitors, including suberoylanilide hydroxamic acid and valproate sodium, with MMS or other DNAdamaging agents, including etoposide and camptothecin. Most of these combined treatments induced cell death additively, but all the tested combinations induced degradation of the core histones synergistically. Meanwhile, we showed that cell cycle arrest might not be a primary consequence for the joint treatment of TSA and MMS. Given that clinic treatments of cancers jointly with an HDAC inhibitor and a DNA-damaging approach often show synergistic effects, histone degradation might more accurately underlie the synergistic effects of these joint treatments in clinic applications than other parameters, such as cell death and cell cycle arrest. Thus, our studies might suggest that the degradation of the core histones can serve as a new target for the development of cancer therapies.展开更多
文摘From Jan</span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;"> 2013 to Nov</span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;"> 2018, we carried out the investigation on vegetation studies in the ecological monitoring programs, Shenzhen</span><span style="font-family:Verdana;"> and</span><span style="font-family:""><span style="font-family:Verdana;"> totally researched 170 plant communities of mountain areas etc., </span><span style="font-family:Verdana;">few areas of street regions and parks etc., for communities’ structural characteristics and plant diversity. We comparatively analyzed natural forests, semi-natural forest and artificial forest composition and structural characters and family, genus and species diversity level and the main affected factors. We also researched and analyzed these communities’ structural characteristics and pant diversity, </span><span style="font-family:Verdana;">comparatively analyzed natural forests, semi-natural forest and artificial forest composition and structural characters and family, genus and species diversity level, the main affected factors;researched and analyzed the relationship between plant community structure characteristics with the absorbing ability to PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;"> pollutants. The result showed that the structure and plant diversity of natural </span><span style="font-family:Verdana;">forest </span></span><span style="font-family:Verdana;">were </span><span style="font-family:Verdana;">obviously better than</span><span style="font-family:Verdana;"> artificial disturbed forest or artificial forest, the semi-natural forest w</span><span style="font-family:Verdana;">as</span><span style="font-family:Verdana;"> the middle level of the forests, In the indices of height, DBH, coverage and crow width etc. of tree layer, natural forests and semi-natural forests were obvious higher than that of artificial disturbed forest or artificial forest;in some forests of artificial disturbed forest or artificial forest, though their richness indices of family and genus were a slightly higher, but this contribution was majorly due to herb layer plants, and some shrub layer plants. Analyz</span><span style="font-family:Verdana;">ing</span><span style="font-family:Verdana;"> three kinds of communities, the number of tree layer species of natural forest was</span><span style="font-family:Verdana;"> the </span><span style="font-family:""><span style="font-family:Verdana;">largest, and their every </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-diversity index value was </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">highest;these characteristics values of semi-natural forest were second, artificial disturbed forests or artificial forests were </span><span style="font-family:Verdana;">the </span><span style="font-family:""><span style="font-family:Verdana;">lowest;in shrub layer, and herb layer, few </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-diversity indices of artificial disturbed forest or artificial forest were </span><span style="font-family:Verdana;">a slightly higher than that of some natural forests, but the integral values of the diversity indices of natural forest and semi-natural forest were obvious</span></span><span style="font-family:Verdana;">ly</span><span style="font-family:Verdana;"> higher than the former. The research showed that in the artificial disturbed forest or artificial forest, because there have some little scale clearing area</span><span style="font-family:Verdana;">s</span><span style="font-family:""><span style="font-family:Verdana;">, so some pioneer plant species could enter the community and formed a temporarily </span><span style="font-family:Verdana;">increase of species diversity, however</span></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> these species major </span><span style="font-family:Verdana;">were</span><span style="font-family:Verdana;"> some shrub and herb plants;but tree layer possessed obvious</span><span style="font-family:Verdana;">ly</span><span style="font-family:Verdana;"> more, even surpass</span><span style="font-family:Verdana;">ed</span><span style="font-family:Verdana;"> several ten times biomass than shrub and herb layers</span><span style="font-family:Verdana;">.</span><span style="font-family:Verdana;"> Therefore</span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> the respect</span><span style="font-family:Verdana;">s</span><span style="font-family:""><span style="font-family:Verdana;"> of maintain ecosystem stability and other</span><span style="font-family:Verdana;"> ecological efficient have </span><span style="font-family:Verdana;">major and dominated position and so on;and then this community can </span></span><span style="font-family:Verdana;">be </span><span style="font-family:Verdana;">natural recovery and succession, those forementioned new entire plants shall withdraw from the community and are replaced by the original plants of the community;but this process has already caused the ecological efficient loss and ecosystem unstable. Above research results are better evidence and theory reference to the argument problems on that </span><span style="font-family:Verdana;">are</span><span style="font-family:""><span style="font-family:Verdana;"> natural forest and natural restoration forest biodiversity higher? or is artificial forest biodiversity higher? and or is more artificial disturbed forest higher?</span><span style="font-family:Verdana;"> Our researches showed that used random investigation method set quadrats, and combined typical investigation method, the structural indices in the all layer of community and all diversity indices of tree, shrub and herb layers and the integral values </span></span><span style="font-family:Verdana;">were</span><span style="font-family:""><span style="font-family:Verdana;"> similar, same or usually these indices in the community which set 600 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">, 800 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> total quatrat area were higher (</span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-diversity) than that of more than 3000 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">, 4000 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> or 7000 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">, even more than 17,000 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> total qua</span></span><span style="font-family:Verdana;">d</span><span style="font-family:Verdana;">rat area of communities. These lot</span><span style="font-family:Verdana;">s</span><span style="font-family:""><span style="font-family:Verdana;"> of researches further proved that according to minimum area method for vegetation survey, in subtropical region, using random investigation method combined with typical investigation set 400 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> or 400 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> - 500 m</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> total qua</span></span><span style="font-family:Verdana;">d</span><span style="font-family:""><span
基金supported by the National Natural Science Foundation of China (31530014, 91319303 & 31600626)
文摘The anticancer therapies with the joint treatment of a histone deacetylase(HDAC) inhibitor and a DNA-damaging approach are actively under clinical investigations, but the underlying mechanism is unclear. Histone homeostasis is critical to genome stability, transcriptional accuracy, DNA repair process, senescence, and survival. We have previously demonstrated that the HDAC inhibitor, trichostatin A(TSA), could promote the degradation of the core histones induced by γ-radiation or the DNAalkylating agent methyl methanesulfonate(MMS) in non-cancer cells, including mouse spermatocyte and embryonic fibroblast cell lines. In this study, we found that the joint treatment by TSA and MMS induced the death of the cultured cancer cells with an additive effect, but induced degradation of the core histones synergistically in these cells. We then analyzed various combinations of other HDAC inhibitors, including suberoylanilide hydroxamic acid and valproate sodium, with MMS or other DNAdamaging agents, including etoposide and camptothecin. Most of these combined treatments induced cell death additively, but all the tested combinations induced degradation of the core histones synergistically. Meanwhile, we showed that cell cycle arrest might not be a primary consequence for the joint treatment of TSA and MMS. Given that clinic treatments of cancers jointly with an HDAC inhibitor and a DNA-damaging approach often show synergistic effects, histone degradation might more accurately underlie the synergistic effects of these joint treatments in clinic applications than other parameters, such as cell death and cell cycle arrest. Thus, our studies might suggest that the degradation of the core histones can serve as a new target for the development of cancer therapies.
