Invasive macroalgae are recognized as one of the greatest threats to local marine ecology and economy.Chaetomorpha valida is an invasive species in China,originally found in Dalian City,Liaoning Province,and has now i...Invasive macroalgae are recognized as one of the greatest threats to local marine ecology and economy.Chaetomorpha valida is an invasive species in China,originally found in Dalian City,Liaoning Province,and has now invaded southward to seas such as Rongcheng City,Shandong Province.Its overgrowth has seriously damaged the local mariculture industry.Based on two strains of C.valida isolated in our previous study,this study explores the effects of temperature and irradiance on their growth and reproduction under laboratory conditions.The results show that the suitable temperature ranges are primarily 21−29℃.The optimal temperature is 25℃for gametophytic growth and sporophytic asexual reproduction,and 29℃for sporophytic growth and gametophytic sexual reproduction.And there is no significant effect of irradiance on their growth and reproduction.Meanwhile,the suitable temperature ranges and optimum irradiance for the growth and reproduction of both strains are largely similar,with only slight differences in the suitable ones for sporophytic asexual reproduction and gametophytic growth.Accordingly,the effect of temperature on the isomorphic generation alternation in C.valida was analyzed,as well as the dynamics of its generation alternation and invasive potential for its environmental adaptation in the northern and southern seas of China.This will help to understand its dynamic pattern spreading from the north to south in China,and also be an important reference for understanding the generation alternation characteristics,invasions and prevention of the outbreaks of other green tidal algae.展开更多
Objective To investigate the association between plasminogen activator inhibitor(PAI)-2 expression and invasive potential in hepatocellular carcinoma(HCC) cells.Methods The HCC cell lines with high,low,and non-metasta...Objective To investigate the association between plasminogen activator inhibitor(PAI)-2 expression and invasive potential in hepatocellular carcinoma(HCC) cells.Methods The HCC cell lines with high,low,and non-metastatic potentials,namely MHCC97-H,MHCC97-L,and SMMC-7721 respectively,were cultured in vitro.Matrigel invasion assay and Western blot of PAI-2 protein expression were conducted.Results The number of invaded cells in MHCC97-L was significantly higher than that in SMMC-7721(P=0.005),whereas that in MHCC97-H was higher than in MHCC97-L(P=0.017) and SMMC-7721(P=0.001).Contrarily,PAI-2 protein expression was gradually reducing from SMMC-7721,MHCC97-L,to MHCC97-H(MHCC97-H vs.MHCC97-L,P<0.001;MHCC97-H vs.SMMC-7721,P=0.001;MHCC97-L vs.SMMC-7721,P=0.001).The Pearson's correlation analysis revealed a significant negative association between invaded cell number and PAI-2 expression(r= 0.892,P=0.001).Conclusion PAI-2 expression may be negatively associated with the invasive potential of HCC.展开更多
Veredas are regarded as humid complexes of ecological, water and scenery significance in Cerrado biome related to water table outcrop. Direct alterations in these environments can lead to species diversity reduction a...Veredas are regarded as humid complexes of ecological, water and scenery significance in Cerrado biome related to water table outcrop. Direct alterations in these environments can lead to species diversity reduction and also facilitate biological invasion processes. Thus our study aims to investigate the natural regeneration, the coverage of woody vegetation and the invasive species in two sites in secondary successional stage in the central part of Cerrado biome. Our study was carried out at two sites located at Minas Gerais state, Brazil. We established plots randomly throughout transects laid perpendicularly to the vereda’s drain line. We used the line intercept method to analyze the vegetation coverage. We set five 10-m width transects in each of both areas, perpendicular to the vereda’s drain line to evaluate the distribution of invasive alien species in the two areas. The richness did not vary between communities (U = 67.50;p = 0.061);on the other hand we found significant difference in density estimates (U = 36.50;p = 0.002). We found significant difference between categories for soil coverage in both sites. Grasses showed the highest coverage when compared to the other categories (K = 45.06;p < 0.001 for site 1 and K = 67.47;p < 0.001 for site 2). We observed a zonation tendency in site 1, with a higher native grass coverage at middle and backwards zones (K = 7.734, p < 0.05). We only found Pinus caribaea Morelet individuals in the invasive species survey. We recorded 46 Pinus caribaea individuals at site 1 and 116 Pinus caribaea individuals at site 2. From the latter group we found 13 individuals within the vereda and 103 in the surrounding vegetation. Both sites have a high natural woody plant regeneration potential although the presence of alien grasses in the veredas’ edge and Pinus caribaea all over the humidity gradient highlights the vulnerability of these areas to biological invasion.展开更多
基金The National Natural Science Foundation of China under contract Nos 32270219 and 31970216.
文摘Invasive macroalgae are recognized as one of the greatest threats to local marine ecology and economy.Chaetomorpha valida is an invasive species in China,originally found in Dalian City,Liaoning Province,and has now invaded southward to seas such as Rongcheng City,Shandong Province.Its overgrowth has seriously damaged the local mariculture industry.Based on two strains of C.valida isolated in our previous study,this study explores the effects of temperature and irradiance on their growth and reproduction under laboratory conditions.The results show that the suitable temperature ranges are primarily 21−29℃.The optimal temperature is 25℃for gametophytic growth and sporophytic asexual reproduction,and 29℃for sporophytic growth and gametophytic sexual reproduction.And there is no significant effect of irradiance on their growth and reproduction.Meanwhile,the suitable temperature ranges and optimum irradiance for the growth and reproduction of both strains are largely similar,with only slight differences in the suitable ones for sporophytic asexual reproduction and gametophytic growth.Accordingly,the effect of temperature on the isomorphic generation alternation in C.valida was analyzed,as well as the dynamics of its generation alternation and invasive potential for its environmental adaptation in the northern and southern seas of China.This will help to understand its dynamic pattern spreading from the north to south in China,and also be an important reference for understanding the generation alternation characteristics,invasions and prevention of the outbreaks of other green tidal algae.
基金Supported by the National High Technology Research and Development Program of China (863 Program,2006AA02A308)the National Key Technologies Research and Development Program of China (2008ZX10002-016)the Beijing Municipal Key Project(H030230280410)
文摘Objective To investigate the association between plasminogen activator inhibitor(PAI)-2 expression and invasive potential in hepatocellular carcinoma(HCC) cells.Methods The HCC cell lines with high,low,and non-metastatic potentials,namely MHCC97-H,MHCC97-L,and SMMC-7721 respectively,were cultured in vitro.Matrigel invasion assay and Western blot of PAI-2 protein expression were conducted.Results The number of invaded cells in MHCC97-L was significantly higher than that in SMMC-7721(P=0.005),whereas that in MHCC97-H was higher than in MHCC97-L(P=0.017) and SMMC-7721(P=0.001).Contrarily,PAI-2 protein expression was gradually reducing from SMMC-7721,MHCC97-L,to MHCC97-H(MHCC97-H vs.MHCC97-L,P<0.001;MHCC97-H vs.SMMC-7721,P=0.001;MHCC97-L vs.SMMC-7721,P=0.001).The Pearson's correlation analysis revealed a significant negative association between invaded cell number and PAI-2 expression(r= 0.892,P=0.001).Conclusion PAI-2 expression may be negatively associated with the invasive potential of HCC.
基金We would like to thank Duratex for funding the project of which this study is partWe are also thankful to the graduate Program in Ecology and Natural Resources Conservation and CAPES for the graduate scholarship provided.
文摘Veredas are regarded as humid complexes of ecological, water and scenery significance in Cerrado biome related to water table outcrop. Direct alterations in these environments can lead to species diversity reduction and also facilitate biological invasion processes. Thus our study aims to investigate the natural regeneration, the coverage of woody vegetation and the invasive species in two sites in secondary successional stage in the central part of Cerrado biome. Our study was carried out at two sites located at Minas Gerais state, Brazil. We established plots randomly throughout transects laid perpendicularly to the vereda’s drain line. We used the line intercept method to analyze the vegetation coverage. We set five 10-m width transects in each of both areas, perpendicular to the vereda’s drain line to evaluate the distribution of invasive alien species in the two areas. The richness did not vary between communities (U = 67.50;p = 0.061);on the other hand we found significant difference in density estimates (U = 36.50;p = 0.002). We found significant difference between categories for soil coverage in both sites. Grasses showed the highest coverage when compared to the other categories (K = 45.06;p < 0.001 for site 1 and K = 67.47;p < 0.001 for site 2). We observed a zonation tendency in site 1, with a higher native grass coverage at middle and backwards zones (K = 7.734, p < 0.05). We only found Pinus caribaea Morelet individuals in the invasive species survey. We recorded 46 Pinus caribaea individuals at site 1 and 116 Pinus caribaea individuals at site 2. From the latter group we found 13 individuals within the vereda and 103 in the surrounding vegetation. Both sites have a high natural woody plant regeneration potential although the presence of alien grasses in the veredas’ edge and Pinus caribaea all over the humidity gradient highlights the vulnerability of these areas to biological invasion.
