The freshwater luminescent bacteria Vibrio-qinghaiensis sp.-Q67 test and the Vicia faba root tip test associated with solid-phase extraction were applied for cytotoxicity and genotoxicity assessment of organic substan...The freshwater luminescent bacteria Vibrio-qinghaiensis sp.-Q67 test and the Vicia faba root tip test associated with solid-phase extraction were applied for cytotoxicity and genotoxicity assessment of organic substances in three rivers, two lakes and effluent flows from two wastewater treatment plants （WWTPs） in Xi＇an, China. Although the most seriously polluted fiver with high chemical oxygen demand （COD） and total organic carbon （TOC） showed high cytotoxicity （expressed as TIIs0, the toxicity impact index） and genotoxicity （expressed as RMCN, the relative frequency of micronucleus）, no correlative relation was found between the ecotoxicity and organic content of the water samples. However, there was a linear correlative relation between TIIs0 and RMCN for most water samples except that from the Zaohe River, which receives discharge from WWTP and untreated industrial wastewaters. The ecotoxicity of the organic toxicants in the Chanhe River and Zaohe River indicated that cytotoxic and genotoxic effects were related to the pollutant source. The TII50 and RMCN were also found to correlate roughly to the dissolved oxygen concentration of the water. Sufficient dissolved oxygen in surface water is thus proved to be an indicator of a healthy water environmental condition.展开更多
In this study on the mutagenic effects of different concentrations of chromium trioxide (CrO3) on Vicia faba root tip, micronucleus assay and chromosome aberration assay were used to determine the mitotic indexes, mic...In this study on the mutagenic effects of different concentrations of chromium trioxide (CrO3) on Vicia faba root tip, micronucleus assay and chromosome aberration assay were used to determine the mitotic indexes, micronucleus rate and chromosome aberration rate of Vicia faba root tip cells. The results showed that the effects of CrO3 concentration on the mitotic indexes were complicated. CrO3 increases the micronucleus rate of Vicia faba root tip cells. It was found that within certain range of CrO3 concentration the micronucleus rate increased systematically with increased concentration of CrO3, but that the micronucleus rate decreased at higher level of CrO3 and that CrO3 also caused various types of chromosome aberration at a rate which increased systematically with increased concentration of CrO3. We concluded that CrO3 has significant mutagenic effect on Vicia faba root tip cells.展开更多
Salinity treatments （NaCl and Na2SO4） reduced plant growth and increased the accumulation of Na^＋, P^3＋,Fe^3＋ , Mn^2＋, and CIin root, stem, leaf and legume. The uptake of K^＋ reduced in the presence of both sal...Salinity treatments （NaCl and Na2SO4） reduced plant growth and increased the accumulation of Na^＋, P^3＋,Fe^3＋ , Mn^2＋, and CIin root, stem, leaf and legume. The uptake of K^＋ reduced in the presence of both salts whereas uptake of Ca^2＋ retarded mainly by Na2SO4. Chlorophyll content was affected mainly by NaCl, while Na2SO4 treatment lowered the rate of photosynthetic activity. Both salt compounds caused accumulation of free amino acids including free proline but reduced the protein content in the leaves. The salt tolerance capacity of the broad beans plant in which the observations of the effect of salinity determined by different concentrations of NaCI and Na2SO4 on growth, chloroplast pigments, photosynthetic, free amino acids, free proline, protein and inorganic elements on plants are combined with observations on growth and yield, in order to arrive at a better understanding of their salt tolerance, has been studied and discussed in this paper. The results for the latter only （fruiting stage） are presented.展开更多
The wall loosening of guard cells differs from other types of plant cells. However, the regulation of wall loosening during stomatal movement is poorly understood. VfEXPA1 is an α-expansin gene cloned from Vicia faba...The wall loosening of guard cells differs from other types of plant cells. However, the regulation of wall loosening during stomatal movement is poorly understood. VfEXPA1 is an α-expansin gene cloned from Vicia faba epidermal strips. Expression of VfEXPA1 is regulated by darkness and submergence, and is not affected by light and abscisic acid (ABA). In situ hybridization showed that VfEXPA1 is expressed primarily in the guard cells. Overexpression of VfEXPA1 in transgenic tobacco accelerated light-induced stomatal opening, and increased both transpiration and photosynthetic rates under favorable growth conditions. Our results indicate the guard cell-expressed expansin VfEXPA1 plays an important role in regulation of stomatal opening.展开更多
【目的】从印染污水处理厂污泥中筛选孔雀石绿脱色菌,并分析比较染料脱色前后毒性。【方法】采用平板稀释涂布法筛选分离纯化菌株,通过扫描电镜、16S r RNA基因序列分析对菌株进行初步鉴定,采用蚕豆根尖微核毒性试验和小球藻毒性试验对...【目的】从印染污水处理厂污泥中筛选孔雀石绿脱色菌,并分析比较染料脱色前后毒性。【方法】采用平板稀释涂布法筛选分离纯化菌株,通过扫描电镜、16S r RNA基因序列分析对菌株进行初步鉴定,采用蚕豆根尖微核毒性试验和小球藻毒性试验对染料脱色前后毒性进行分析。【结果】从印染污水处理厂污泥中筛选出一株高效孔雀石绿脱色菌。经过16S r RNA基因序列分析,鉴定该菌株为Klebsiella sp.JD。菌株的菌落边缘规则,圆形,灰白色粘稠,以接种环挑之,易拉成丝,表面光滑。通过对比小球藻在脱色前后的生长率和抑制率以及蚕豆微核率和污染指数分析出脱色后的染料毒性大大降低。【结论】筛选得到一株新的孔雀石绿脱色菌,该菌降解效率高,可降低染料毒性,对修复染料污染的水体有一定的现实意义。展开更多
In animal cells, action of acetylcholine depends on its binding with its two specific receptors on the plasma membrane: the nicotinic and muscarinic respectively. The present investigation has shown that agonists of m...In animal cells, action of acetylcholine depends on its binding with its two specific receptors on the plasma membrane: the nicotinic and muscarinic respectively. The present investigation has shown that agonists of muscarinic receptor (muscarine) could induce stomatal opening, while the antagonists (atropine) could block stomatal opening induced by acetylcholine. Their effects can only be realized in medium containing Ca2+, but not in medium containing K+. The results tend to reveal that the muscarinic receptor is involved in acetylcholine-induced stomatal movement.展开更多
In this study, micronucleus （MCN） and chromosome aberration （CA） tests in Vicia faba root tip cells were carried out in order to assess the water quality and the comprehensive genotoxic potential of surface waters...In this study, micronucleus （MCN） and chromosome aberration （CA） tests in Vicia faba root tip cells were carried out in order to assess the water quality and the comprehensive genotoxic potential of surface waters located in the urban area of Xi＇an City, China. For these evaluations, water samples from different surface waters （four rivers, two lakes, two biological treatment plant effluents） were collected, the ultra-pure water and methyl methanesulfonate solution was used as the negative and positive control, respectively. In our results, highly significant differences in MCN perrnillage （average number of micronuclei per 1000 cells）, CA frequencies and PI （pollution index） values were found among three rivers and two WWTP effluents, the tested samples from two rivers caused the decrease of mitotic index over 22% compared with the negative control. No significant changes were observed in micronuclei and chromosome aberrations frequencies at one river and two lakes during the period of test （wet season）. These results point out a poor state of the water quality and genotoxic activity of the main surface waters in Xi＇an City. It is recommended to establish a monitoring program for the presence of genotoxic agents in these surface waters.展开更多
基金supported by the National Natural Science Foundation of China (No. 50838005)the Program for Changjiang Scholars and Innovative Research Team inUniversity (No. IRT0853)the National Program of Water Pollution Control (No. 2008ZX07317-004)
文摘The freshwater luminescent bacteria Vibrio-qinghaiensis sp.-Q67 test and the Vicia faba root tip test associated with solid-phase extraction were applied for cytotoxicity and genotoxicity assessment of organic substances in three rivers, two lakes and effluent flows from two wastewater treatment plants （WWTPs） in Xi＇an, China. Although the most seriously polluted fiver with high chemical oxygen demand （COD） and total organic carbon （TOC） showed high cytotoxicity （expressed as TIIs0, the toxicity impact index） and genotoxicity （expressed as RMCN, the relative frequency of micronucleus）, no correlative relation was found between the ecotoxicity and organic content of the water samples. However, there was a linear correlative relation between TIIs0 and RMCN for most water samples except that from the Zaohe River, which receives discharge from WWTP and untreated industrial wastewaters. The ecotoxicity of the organic toxicants in the Chanhe River and Zaohe River indicated that cytotoxic and genotoxic effects were related to the pollutant source. The TII50 and RMCN were also found to correlate roughly to the dissolved oxygen concentration of the water. Sufficient dissolved oxygen in surface water is thus proved to be an indicator of a healthy water environmental condition.
文摘In this study on the mutagenic effects of different concentrations of chromium trioxide (CrO3) on Vicia faba root tip, micronucleus assay and chromosome aberration assay were used to determine the mitotic indexes, micronucleus rate and chromosome aberration rate of Vicia faba root tip cells. The results showed that the effects of CrO3 concentration on the mitotic indexes were complicated. CrO3 increases the micronucleus rate of Vicia faba root tip cells. It was found that within certain range of CrO3 concentration the micronucleus rate increased systematically with increased concentration of CrO3, but that the micronucleus rate decreased at higher level of CrO3 and that CrO3 also caused various types of chromosome aberration at a rate which increased systematically with increased concentration of CrO3. We concluded that CrO3 has significant mutagenic effect on Vicia faba root tip cells.
文摘Salinity treatments （NaCl and Na2SO4） reduced plant growth and increased the accumulation of Na^＋, P^3＋,Fe^3＋ , Mn^2＋, and CIin root, stem, leaf and legume. The uptake of K^＋ reduced in the presence of both salts whereas uptake of Ca^2＋ retarded mainly by Na2SO4. Chlorophyll content was affected mainly by NaCl, while Na2SO4 treatment lowered the rate of photosynthetic activity. Both salt compounds caused accumulation of free amino acids including free proline but reduced the protein content in the leaves. The salt tolerance capacity of the broad beans plant in which the observations of the effect of salinity determined by different concentrations of NaCI and Na2SO4 on growth, chloroplast pigments, photosynthetic, free amino acids, free proline, protein and inorganic elements on plants are combined with observations on growth and yield, in order to arrive at a better understanding of their salt tolerance, has been studied and discussed in this paper. The results for the latter only （fruiting stage） are presented.
基金supported by the National Basic Research Program of China (2006CB100100, 2003CB114300)the National Natural Science Foundation of China (30370129, 30421002)
文摘The wall loosening of guard cells differs from other types of plant cells. However, the regulation of wall loosening during stomatal movement is poorly understood. VfEXPA1 is an α-expansin gene cloned from Vicia faba epidermal strips. Expression of VfEXPA1 is regulated by darkness and submergence, and is not affected by light and abscisic acid (ABA). In situ hybridization showed that VfEXPA1 is expressed primarily in the guard cells. Overexpression of VfEXPA1 in transgenic tobacco accelerated light-induced stomatal opening, and increased both transpiration and photosynthetic rates under favorable growth conditions. Our results indicate the guard cell-expressed expansin VfEXPA1 plays an important role in regulation of stomatal opening.
文摘【目的】从印染污水处理厂污泥中筛选孔雀石绿脱色菌,并分析比较染料脱色前后毒性。【方法】采用平板稀释涂布法筛选分离纯化菌株,通过扫描电镜、16S r RNA基因序列分析对菌株进行初步鉴定,采用蚕豆根尖微核毒性试验和小球藻毒性试验对染料脱色前后毒性进行分析。【结果】从印染污水处理厂污泥中筛选出一株高效孔雀石绿脱色菌。经过16S r RNA基因序列分析,鉴定该菌株为Klebsiella sp.JD。菌株的菌落边缘规则,圆形,灰白色粘稠,以接种环挑之,易拉成丝,表面光滑。通过对比小球藻在脱色前后的生长率和抑制率以及蚕豆微核率和污染指数分析出脱色后的染料毒性大大降低。【结论】筛选得到一株新的孔雀石绿脱色菌,该菌降解效率高,可降低染料毒性,对修复染料污染的水体有一定的现实意义。
文摘In animal cells, action of acetylcholine depends on its binding with its two specific receptors on the plasma membrane: the nicotinic and muscarinic respectively. The present investigation has shown that agonists of muscarinic receptor (muscarine) could induce stomatal opening, while the antagonists (atropine) could block stomatal opening induced by acetylcholine. Their effects can only be realized in medium containing Ca2+, but not in medium containing K+. The results tend to reveal that the muscarinic receptor is involved in acetylcholine-induced stomatal movement.
基金Acknowledgements This study is supported by the National Natural Science Foundation of China （Grant No. 51178377）, the Key Laboratory Foundation of Shaanxi Provice （No. 2010JS026） and the Program for Changjiang Scholars and Innovative Research Team in University （No. 1RT0853）.
文摘In this study, micronucleus （MCN） and chromosome aberration （CA） tests in Vicia faba root tip cells were carried out in order to assess the water quality and the comprehensive genotoxic potential of surface waters located in the urban area of Xi＇an City, China. For these evaluations, water samples from different surface waters （four rivers, two lakes, two biological treatment plant effluents） were collected, the ultra-pure water and methyl methanesulfonate solution was used as the negative and positive control, respectively. In our results, highly significant differences in MCN perrnillage （average number of micronuclei per 1000 cells）, CA frequencies and PI （pollution index） values were found among three rivers and two WWTP effluents, the tested samples from two rivers caused the decrease of mitotic index over 22% compared with the negative control. No significant changes were observed in micronuclei and chromosome aberrations frequencies at one river and two lakes during the period of test （wet season）. These results point out a poor state of the water quality and genotoxic activity of the main surface waters in Xi＇an City. It is recommended to establish a monitoring program for the presence of genotoxic agents in these surface waters.
