To mutagenize two conserved CCCT and PTK motifs in the central domain of Chinese strain of potato Y potyvirus (PVY-C) helper component proteinase (HC-Pro), four mutants of HC-Pro gene were obtained by PCR and site-dir...To mutagenize two conserved CCCT and PTK motifs in the central domain of Chinese strain of potato Y potyvirus (PVY-C) helper component proteinase (HC-Pro), four mutants of HC-Pro gene were obtained by PCR and site-directed mutagenesis, and then were inserted into the constitutive expression vector pBin438. Leaves from tobacco (Nicotiana tabacum L. cv. K326) were transformed with these four plant expression plasmids by Agrobacterium-mediated transformation, respectively. Southern and Western blotting analyses showed that these four mutants were integrated into tobacco genomic DNA and could express the corresponding proteins in most of die transgenic plants. The challenge of transgenic plants with potato X potexvirus (PVX) revealed that the expression products of PVY-C HC-Pro mutants in transgenic plants greatly abolished functions of HC-Pro in enhancing the accumulation and pathogenicity of PVX, indicating that CCCT and PTK motifs of HC-Pro were required for PVX/PVY synergism. Meanwhile, the results demonstrated that PVY-C HC-Pro had a function in accelerating the long-distance movement of PVX in these transgenic plants for the first time.展开更多
[Objective] This study was to develop a live vector vaccine of goat pox virus of Peste des petits ruminants(PPR). [Method] Using PCR amplification technique, PPR H gene was obtained, then ligated into pGEM-T easy vect...[Objective] This study was to develop a live vector vaccine of goat pox virus of Peste des petits ruminants(PPR). [Method] Using PCR amplification technique, PPR H gene was obtained, then ligated into pGEM-T easy vector; the recombinants were digested by Nhe Ⅰ and Hind Ⅲ, and ligated into pEGFP-N1-P7.5, yielding the recombinant vector pEGFP-N1-P7.5-H; next the expression cassette EGFP-N1-P7.5-H was first released from recombinant vector pEGFP-N1-P7.5-H by double digestion of Hind Ⅲ and Nhe Ⅰ and ligated into pUC119-TK that was digested by Kpn Ⅰ, yielding the transfer vector pUC119-TK-EGFP-P7.5-H. [Result] Identification and double enzyme digestion showed that the transfer vector pUC119-TK-EGFP-P7.5-H was correctly constructed. From the transfer vector transfected BHK-21 cells which infected GTPV AV41, specific fluorescence was observed at 48th h of transfection. [Conclusion] The construction of goat poxvirus live vector laid a foundation for the live vector vaccine of PPR vaccine.展开更多
Allelochemicals of Chinese-fir root was extracted by technology ofsupercritical CO_2 extraction under orthogonal experiment design, and it was used to analyzeallelopathic activity of Chinese-fir through bioassay of se...Allelochemicals of Chinese-fir root was extracted by technology ofsupercritical CO_2 extraction under orthogonal experiment design, and it was used to analyzeallelopathic activity of Chinese-fir through bioassay of seed germination. The results showed thatas to the available rate of allelochemicals, the pressure and temperature of extraction were themost important factors. The allelochemicals of Chinese-fir root extracted by pure CO_2 and ethanolmixed with CO_2 have different allelopathic activities to seed germination, and the allelochemicalsextracted by ethanol mixed with CO_2 had stronger inhibitory effects on seed germination than thatextracted by pure CO_2.展开更多
Objective: To study the reversal effect of neferine on adriamycin (ADM) resistant human breast cancer cell line MCF-7/ADM. Methods: The cytotoxic effect of Nef or ADM was determined by 3-[4, 5-dimethylthiazol-2.-yl], ...Objective: To study the reversal effect of neferine on adriamycin (ADM) resistant human breast cancer cell line MCF-7/ADM. Methods: The cytotoxic effect of Nef or ADM was determined by 3-[4, 5-dimethylthiazol-2.-yl], 5-diphenyl tetraxolium bromid (MTT) assay. Apoptosis and the expression of P-glycoprotein (P-gp) were detected by flow cytometry (FCM). The intracellular ADM concentration was measured by HPLC. Results: Nef at 1, 5, 10 mol/L decreased the IC50 of ADM to MCF-7/ADM from 11.63 g/mL to 4.59, 2.44, 0.27 g/mL respectively. MCF-7/ADM could resist the apoptosis induced by ADM while Nef (1-10 mol/L) could augment ADR-mediated apoptosis. Nef (10 mol/L) increased the accumulation of ADM up to 2.88 fold in MCF-7/ADM but not in sensitive cells MCF-7/S and reduced the expression of P-gp in MCF-7/ADM cells. Conclusion: Nef can circumvent multidrug resistance (MDR) of MCF-7/ADM cells and the mechanism was associated with the increase of intracellular accumulation of ADM and the reduced expression of P-gp in MCF-7/ADM cells.展开更多
Allelochemicals of Chinese-fir root was extracted by technology of supercritical CO2 extraction under orthogonal experiment design, and it was used to analyze allelopathic activity of Chinese-fir through bioassay of s...Allelochemicals of Chinese-fir root was extracted by technology of supercritical CO2 extraction under orthogonal experiment design, and it was used to analyze allelopathic activity of Chinese-fir through bioassay of seed germination. The results showed that as to the available rate of allelochemicals, the pressure and temperature of extraction were the most important factors. The allelochemicals of Chinese-fir root extracted by pure CO2 and ethanol mixed with CO2 have different allelopathic activities to seed germination, and the allelochemicals extracted by ethanol mixed with CO2 had stronger inhibitory effects on seed germination than that extracted by pure CO2.展开更多
[Objective ]The aim of this study was to improve the photostability of pho-tosensitizers. [Method] 2,5-Diphenylthiophene and 2,5-dithienylethynylthiophene were synthesized by replacing thiophene rings of α-terthienyl...[Objective ]The aim of this study was to improve the photostability of pho-tosensitizers. [Method] 2,5-Diphenylthiophene and 2,5-dithienylethynylthiophene were synthesized by replacing thiophene rings of α-terthienyl (α-T) with benzene rings. Photoactivated activities on Spodoptera litura (SL) cells, singlet oxygen with UV and photostability of photosensitizers were investigated. [Result] The cytotoxicity of pho-tosensitizer 2,5-diphenylthiophene on SL cells was 0.22 and 0.16 μg/ml after treat-ment for 24 and 48 h, respectively, while that of 2,5-dithienylethynylthiophene on SL cells was 0.06 and 0.04 μg/ml. Singlet oxygen of 2,5-diphenylthiophene and 2,5-dithienylethynylthiophene was 1.047 5, 1.529 4 μg/mmol under UV, respectively. Degradation dynamic equations of 2,5-diphenylthiophene and 2,5-dithienylethynylthio-phene in methanol were Ct= 5.227 1e-0.006 1t, Ct= 5.084 2e-0.097 3t and half life was 111.79, 7.12 h. [Conclusion] Photosensitizer 2,5-diphenylthiophene has high singlet oxygen production ability, and high photoactivated cytotoxicity on SL cells under UV. Moreover, 2,5-diphenylthiophene has overcome the deficiency of photoactivated in-secticides, which is not applied directly in field because it degrades quickly in the environment.展开更多
Objective: To evaluate the effectiveness of intraoperative radiotherapy (IORT) in combination with regional chemotherapy in the treatment of advanced pancreatic carcinoma.Methods: 17 patients with advanced pancreatic ...Objective: To evaluate the effectiveness of intraoperative radiotherapy (IORT) in combination with regional chemotherapy in the treatment of advanced pancreatic carcinoma.Methods: 17 patients with advanced pancreatic adenocarcinoma were treated with IORT and regional chemotherapy with 5-FU, Epirubucin and Mitomycin, and 6 cases accepted external radiotherapy postoperatively.Results: 35.29% (6/17) of the patients were clinical benefit responders and 23.53% (4/17) had a partial response. The median survival time was 11 months and the 1-year survival rate was 35.29% (6/17)Conclusion: IORT in combination with regional chemotherapy had a good impact on clinical benefit without severe side effects in locally advanced pancreatic carcinoma and led to a significant prolongation of the survival time. Key words pancreatic cancer - intraoperative radiotherapy - chemotherapy展开更多
The synonymous codon usage in the translational initiation and termination regions of genes of severe acute respiratory syndrome (SARS) coronavirus and five other viruses in Coronaviridae was systematically analyzed.T...The synonymous codon usage in the translational initiation and termination regions of genes of severe acute respiratory syndrome (SARS) coronavirus and five other viruses in Coronaviridae was systematically analyzed.The results indicate that most minor codons for these coronaviruses are preferentially used in the initial and terminal region.The minor codons preferentially used in the initial region are thought to have a negative effect on gene expression,which can be explained by the minor codon modulator hypothesis.It also indicates that the minor codons preferentially used in the terminal region may regulate the level of gene expression.The proposed results strongly imply that the minor codon modulator hypothesis can be applied to both some bacteria and some viruses.展开更多
[Objective] This study aimed to select microalgae species which are capable to effectively remove arsenic contamination from water under natural conditions. [Method] Four microalgae species [Chlorella sp. (zfsaia), ...[Objective] This study aimed to select microalgae species which are capable to effectively remove arsenic contamination from water under natural conditions. [Method] Four microalgae species [Chlorella sp. (zfsaia), Chlorella minata, Chlorella vulgaris and Selenastrum capricormulum] were used as experimental materials and cultured with six different concentrations of As (Ⅲ) (0.5, 1.0, 2.0, 5.0, 10.0, 20.0 mg/L). Biomass, chlorophyll a content and other physiological indicators were determined to investigate the arsenic tolerance and biosorption of four microalgae species. [Result] Chlorella sp. is sensitive to arsenic toxicity, its growth was inhibited when arsenic concentration exceeded 10 mg/L, with an EC 50 of 17.32 mg/L; when the arsenic concentration was 0-20 mg/L, growth of S.c, ww1 and C.v was not affected, which showed relatively high tolerance to arsenic, with arsenic removal rates of 77.02% , 72.18% and 81.36% respectively after 24 h. [Conclusion] This study indicates that microalgae have good application prospects for processing arsenic wastewater and being indicator plants of arsenic wastewater.展开更多
In this study, the bioaccumulation and toxicity of neodymium (Nd) in pla-narian Dugesia japonica were investigated. The results showed that with the in-creasing dietary Nd supplementation, the concentration of Nd in...In this study, the bioaccumulation and toxicity of neodymium (Nd) in pla-narian Dugesia japonica were investigated. The results showed that with the in-creasing dietary Nd supplementation, the concentration of Nd in the planarian showed a significant linear increase and the balance of mineral elements was bro-ken with the decrease of Ca, Fe and Mo, and the increase of K and Mg. The content of soluble proteins and the activities of superoxide dismutase (SOD) and catalase (CAT) decreased with the increase of Nd concentration, while the content of H2O2 rose gradual y. The mortality was directly proportional to the Nd concentra-tion. The results indicated that planarian is a very sensitive aquatic animal to Nd contamination and can be an indicator organism for Nd pol ution.展开更多
Environmental endocrine disrupting chemicals (EDCs), commonly found in the environment, come from industry and agriculture, including pesticides, fungicides, insecticides, herbicides, and other chemicals. Nowadays, ...Environmental endocrine disrupting chemicals (EDCs), commonly found in the environment, come from industry and agriculture, including pesticides, fungicides, insecticides, herbicides, and other chemicals. Nowadays, more and more EDCs were released into the environment. EDCs go into water body via atmosphere sedi-mentation, surface runoff, soil eluviation, etc., so water body becomes the main place for existing. In order to attract scientific and public attention worldwide and to prevent EDCs pol ution, in this study we reviewed the classification of EDCs and their concentrations in natural water bodies, drinking water sources and water plants, and the reproductive toxicity of EDCs to fish were reviewed. EDCs could disturb the endocrine system and make reproductive organs and reproduction abnor-mal, resulting in fertility descending, reproduction function damage, community quan-tity decrease and even species extinction. In addition, EDCs could disrupt the homeostasis maintained by hormones, which would result in defects of neural de-velopment and abnormalities of the endocrine and reproductive systems. The exact molecular mechanisms have not been completely reported, but researches have suggested that multiple mechanisms were involved in the action of EDCs. Although there have been researches on the biohazard of EDCs, there stil exist problems of weakness in fundamental researches, difficulties in recognizing and identifying EDCs and high cost, which restraint the knowledge on them.展开更多
Based on the fact that Fe toxicity which is usually characterized by leaf oranging and low yield canbe obviously subdued by application of Si or Mn due to counteraction between Fe and Si or Mn. A potexperiment was con...Based on the fact that Fe toxicity which is usually characterized by leaf oranging and low yield canbe obviously subdued by application of Si or Mn due to counteraction between Fe and Si or Mn. A potexperiment was conducted with four treatments of CK, Si, Mn and Si+Mn to further study the effect ofcombined application of Si and Mn on rice growth on red earths. Water-soluble Si, Fe and Mn were measured,and electron probe was used to study Si, Mn, Fe and Ca in root cross sections. Combined application of Si andMn could increase water-soluble Si and Mn but reduce water-soluble Fe, thus being favorable for correctingFe toxicity. Electron probe study showed obvious differences of Si, Fe, Mn and Ca in rice roots betweenCK and the other three treatments. The combined application of Si and Mn could reduce leaf oranging andimprove rice growth. The Si+Mn treatment had a higher plant height, lower number of oranging leaves anda 25.0% higher rice yield than CK and showed a better effect on rice growth than the treatment of sole Si orMn.展开更多
The aim of this study was to find out the effects of exogenous phenolic acids on soil microbes and enzymes in rhizosphere soil of adzuki bean. In the pot experiment of adzuki bean, phthalic and cinnamic acids were add...The aim of this study was to find out the effects of exogenous phenolic acids on soil microbes and enzymes in rhizosphere soil of adzuki bean. In the pot experiment of adzuki bean, phthalic and cinnamic acids were added at four concentrations, 0 (control), 0.1, 1 and 10 mmol/L, to investigate the changes in the mi- croflora and enzyme activities in rhizosphere soil of adzuki bean as well as relations between them. The results showed that both phthalic and cinnamic acids could inhibit the activities of soil enzymes, including catalase, sucrase, phosphatase and urease. Higher concentrations (10 mmol/L) of phthalic and cinnamic acids showed more significant effects. In addition, the application of phthalic and cinnamic acids reduced the populations of bacteria and actinomycetes and significantly increased the population of fungi. Correlations analysis showed that phosphatase activity had an extremely significant positive correlation with bacterial population, a significant positive correlation with actinomycete population, and a significant negative correlation with fungal population. Phthalic and cinnamic acids could result in imbalanced microbe compositions, reduce enzyme activities and present evident allelopathy in rhizosphere soil.展开更多
Recent studies have uncovered two signaling pathways that activate the host innate immunity against viral infection. One of the pathways utilizes members of the Toll-like receptor (TLR) family to detect viruses that...Recent studies have uncovered two signaling pathways that activate the host innate immunity against viral infection. One of the pathways utilizes members of the Toll-like receptor (TLR) family to detect viruses that enter the endosome through endocytosis. The TLR pathway induces interferon production through several signaling proteins that ultimately lead to the activation of the transcription factors NF-kB, IRF3 and IRFT. The other antiviral pathway uses the RNA helicase RIG-Ⅰ as the receptor for intracellular viral double-stranded RNA. RIG-Ⅰ activates NF-kB and IRFs through the recently identified adaptor protein MAVS, a CARD domain containing protein that resides in the mitochondrial membrane. MAVS is essential for antiviral innate immunity, but it also serves as a target of Hepatitis C virus (HCV), which employs a viral protease to cleave MAVS off the mitochondria, thereby allowing HCV to escape the host immune system.展开更多
Ecotoxicity and bioavailability of cadmium (Cd) to the maize (Zea mays L.) and the soybean (Glycine max (L.) Merr.) were investigated by acute toxicity experiment in the laboratory with black soil. Ecotoxicity...Ecotoxicity and bioavailability of cadmium (Cd) to the maize (Zea mays L.) and the soybean (Glycine max (L.) Merr.) were investigated by acute toxicity experiment in the laboratory with black soil. Ecotoxicity and bioavailability of Cd were quantified by calculating the median effective concentration (ECs0) and bioaccumulation factor (BAF). The measurement endpoints used were seed germination and seedling growth (shoot and root). The results showed that concentrations of Cd in the soil had adverse effect on the growth of roots and shoots. Seed germination was not the sensitive indicator for the ecotoxicity of Cd in the soil, while the growth of roots was the most sensitive measurement endpoint. Absorbability and transport of Cd in plants depended on the test crop species and Cd concentrations in the soil. The maize retains more Cd in its roots, while the soybean transports more Cd to the shoots from roots.展开更多
文摘To mutagenize two conserved CCCT and PTK motifs in the central domain of Chinese strain of potato Y potyvirus (PVY-C) helper component proteinase (HC-Pro), four mutants of HC-Pro gene were obtained by PCR and site-directed mutagenesis, and then were inserted into the constitutive expression vector pBin438. Leaves from tobacco (Nicotiana tabacum L. cv. K326) were transformed with these four plant expression plasmids by Agrobacterium-mediated transformation, respectively. Southern and Western blotting analyses showed that these four mutants were integrated into tobacco genomic DNA and could express the corresponding proteins in most of die transgenic plants. The challenge of transgenic plants with potato X potexvirus (PVX) revealed that the expression products of PVY-C HC-Pro mutants in transgenic plants greatly abolished functions of HC-Pro in enhancing the accumulation and pathogenicity of PVX, indicating that CCCT and PTK motifs of HC-Pro were required for PVX/PVY synergism. Meanwhile, the results demonstrated that PVY-C HC-Pro had a function in accelerating the long-distance movement of PVX in these transgenic plants for the first time.
文摘[Objective] This study was to develop a live vector vaccine of goat pox virus of Peste des petits ruminants(PPR). [Method] Using PCR amplification technique, PPR H gene was obtained, then ligated into pGEM-T easy vector; the recombinants were digested by Nhe Ⅰ and Hind Ⅲ, and ligated into pEGFP-N1-P7.5, yielding the recombinant vector pEGFP-N1-P7.5-H; next the expression cassette EGFP-N1-P7.5-H was first released from recombinant vector pEGFP-N1-P7.5-H by double digestion of Hind Ⅲ and Nhe Ⅰ and ligated into pUC119-TK that was digested by Kpn Ⅰ, yielding the transfer vector pUC119-TK-EGFP-P7.5-H. [Result] Identification and double enzyme digestion showed that the transfer vector pUC119-TK-EGFP-P7.5-H was correctly constructed. From the transfer vector transfected BHK-21 cells which infected GTPV AV41, specific fluorescence was observed at 48th h of transfection. [Conclusion] The construction of goat poxvirus live vector laid a foundation for the live vector vaccine of PPR vaccine.
基金This paper was supported by Natural Science Foundation of Fujian Province (B0010020)
文摘Allelochemicals of Chinese-fir root was extracted by technology ofsupercritical CO_2 extraction under orthogonal experiment design, and it was used to analyzeallelopathic activity of Chinese-fir through bioassay of seed germination. The results showed thatas to the available rate of allelochemicals, the pressure and temperature of extraction were themost important factors. The allelochemicals of Chinese-fir root extracted by pure CO_2 and ethanolmixed with CO_2 have different allelopathic activities to seed germination, and the allelochemicalsextracted by ethanol mixed with CO_2 had stronger inhibitory effects on seed germination than thatextracted by pure CO_2.
文摘Objective: To study the reversal effect of neferine on adriamycin (ADM) resistant human breast cancer cell line MCF-7/ADM. Methods: The cytotoxic effect of Nef or ADM was determined by 3-[4, 5-dimethylthiazol-2.-yl], 5-diphenyl tetraxolium bromid (MTT) assay. Apoptosis and the expression of P-glycoprotein (P-gp) were detected by flow cytometry (FCM). The intracellular ADM concentration was measured by HPLC. Results: Nef at 1, 5, 10 mol/L decreased the IC50 of ADM to MCF-7/ADM from 11.63 g/mL to 4.59, 2.44, 0.27 g/mL respectively. MCF-7/ADM could resist the apoptosis induced by ADM while Nef (1-10 mol/L) could augment ADR-mediated apoptosis. Nef (10 mol/L) increased the accumulation of ADM up to 2.88 fold in MCF-7/ADM but not in sensitive cells MCF-7/S and reduced the expression of P-gp in MCF-7/ADM cells. Conclusion: Nef can circumvent multidrug resistance (MDR) of MCF-7/ADM cells and the mechanism was associated with the increase of intracellular accumulation of ADM and the reduced expression of P-gp in MCF-7/ADM cells.
基金This paper was supported by Natural Science Foundation of Fujian Province (B0010020)
文摘Allelochemicals of Chinese-fir root was extracted by technology of supercritical CO2 extraction under orthogonal experiment design, and it was used to analyze allelopathic activity of Chinese-fir through bioassay of seed germination. The results showed that as to the available rate of allelochemicals, the pressure and temperature of extraction were the most important factors. The allelochemicals of Chinese-fir root extracted by pure CO2 and ethanol mixed with CO2 have different allelopathic activities to seed germination, and the allelochemicals extracted by ethanol mixed with CO2 had stronger inhibitory effects on seed germination than that extracted by pure CO2.
基金Supported by Science and Technology Support Program of Jiangsu Province(Agricultural Project)(BE2012346)Science and Technology Projects for Social Development of Yangzhou City,China(2012110)Natural Science Foundation of the Jiangsu Higher Education Institutions of China(13KJB210010)~~
文摘[Objective ]The aim of this study was to improve the photostability of pho-tosensitizers. [Method] 2,5-Diphenylthiophene and 2,5-dithienylethynylthiophene were synthesized by replacing thiophene rings of α-terthienyl (α-T) with benzene rings. Photoactivated activities on Spodoptera litura (SL) cells, singlet oxygen with UV and photostability of photosensitizers were investigated. [Result] The cytotoxicity of pho-tosensitizer 2,5-diphenylthiophene on SL cells was 0.22 and 0.16 μg/ml after treat-ment for 24 and 48 h, respectively, while that of 2,5-dithienylethynylthiophene on SL cells was 0.06 and 0.04 μg/ml. Singlet oxygen of 2,5-diphenylthiophene and 2,5-dithienylethynylthiophene was 1.047 5, 1.529 4 μg/mmol under UV, respectively. Degradation dynamic equations of 2,5-diphenylthiophene and 2,5-dithienylethynylthio-phene in methanol were Ct= 5.227 1e-0.006 1t, Ct= 5.084 2e-0.097 3t and half life was 111.79, 7.12 h. [Conclusion] Photosensitizer 2,5-diphenylthiophene has high singlet oxygen production ability, and high photoactivated cytotoxicity on SL cells under UV. Moreover, 2,5-diphenylthiophene has overcome the deficiency of photoactivated in-secticides, which is not applied directly in field because it degrades quickly in the environment.
文摘Objective: To evaluate the effectiveness of intraoperative radiotherapy (IORT) in combination with regional chemotherapy in the treatment of advanced pancreatic carcinoma.Methods: 17 patients with advanced pancreatic adenocarcinoma were treated with IORT and regional chemotherapy with 5-FU, Epirubucin and Mitomycin, and 6 cases accepted external radiotherapy postoperatively.Results: 35.29% (6/17) of the patients were clinical benefit responders and 23.53% (4/17) had a partial response. The median survival time was 11 months and the 1-year survival rate was 35.29% (6/17)Conclusion: IORT in combination with regional chemotherapy had a good impact on clinical benefit without severe side effects in locally advanced pancreatic carcinoma and led to a significant prolongation of the survival time. Key words pancreatic cancer - intraoperative radiotherapy - chemotherapy
文摘The synonymous codon usage in the translational initiation and termination regions of genes of severe acute respiratory syndrome (SARS) coronavirus and five other viruses in Coronaviridae was systematically analyzed.The results indicate that most minor codons for these coronaviruses are preferentially used in the initial and terminal region.The minor codons preferentially used in the initial region are thought to have a negative effect on gene expression,which can be explained by the minor codon modulator hypothesis.It also indicates that the minor codons preferentially used in the terminal region may regulate the level of gene expression.The proposed results strongly imply that the minor codon modulator hypothesis can be applied to both some bacteria and some viruses.
基金Supported by Natural Science Foundation of Guangdong Province (10151064101000041)Ph.D. Funds from Ministry of Education of China(20090172120032)~~
文摘[Objective] This study aimed to select microalgae species which are capable to effectively remove arsenic contamination from water under natural conditions. [Method] Four microalgae species [Chlorella sp. (zfsaia), Chlorella minata, Chlorella vulgaris and Selenastrum capricormulum] were used as experimental materials and cultured with six different concentrations of As (Ⅲ) (0.5, 1.0, 2.0, 5.0, 10.0, 20.0 mg/L). Biomass, chlorophyll a content and other physiological indicators were determined to investigate the arsenic tolerance and biosorption of four microalgae species. [Result] Chlorella sp. is sensitive to arsenic toxicity, its growth was inhibited when arsenic concentration exceeded 10 mg/L, with an EC 50 of 17.32 mg/L; when the arsenic concentration was 0-20 mg/L, growth of S.c, ww1 and C.v was not affected, which showed relatively high tolerance to arsenic, with arsenic removal rates of 77.02% , 72.18% and 81.36% respectively after 24 h. [Conclusion] This study indicates that microalgae have good application prospects for processing arsenic wastewater and being indicator plants of arsenic wastewater.
基金Supported by Department of Environmental Protection--Special Funds for Biological Diversity Conservation(2111101)National Natural Science Foundation of China(30900071)Start-Up Funding for PhD Research at Shandong University of Technology(4041-406027)~~
文摘In this study, the bioaccumulation and toxicity of neodymium (Nd) in pla-narian Dugesia japonica were investigated. The results showed that with the in-creasing dietary Nd supplementation, the concentration of Nd in the planarian showed a significant linear increase and the balance of mineral elements was bro-ken with the decrease of Ca, Fe and Mo, and the increase of K and Mg. The content of soluble proteins and the activities of superoxide dismutase (SOD) and catalase (CAT) decreased with the increase of Nd concentration, while the content of H2O2 rose gradual y. The mortality was directly proportional to the Nd concentra-tion. The results indicated that planarian is a very sensitive aquatic animal to Nd contamination and can be an indicator organism for Nd pol ution.
基金Supported by the China Agriculture Research System(CARS49)~~
文摘Environmental endocrine disrupting chemicals (EDCs), commonly found in the environment, come from industry and agriculture, including pesticides, fungicides, insecticides, herbicides, and other chemicals. Nowadays, more and more EDCs were released into the environment. EDCs go into water body via atmosphere sedi-mentation, surface runoff, soil eluviation, etc., so water body becomes the main place for existing. In order to attract scientific and public attention worldwide and to prevent EDCs pol ution, in this study we reviewed the classification of EDCs and their concentrations in natural water bodies, drinking water sources and water plants, and the reproductive toxicity of EDCs to fish were reviewed. EDCs could disturb the endocrine system and make reproductive organs and reproduction abnor-mal, resulting in fertility descending, reproduction function damage, community quan-tity decrease and even species extinction. In addition, EDCs could disrupt the homeostasis maintained by hormones, which would result in defects of neural de-velopment and abnormalities of the endocrine and reproductive systems. The exact molecular mechanisms have not been completely reported, but researches have suggested that multiple mechanisms were involved in the action of EDCs. Although there have been researches on the biohazard of EDCs, there stil exist problems of weakness in fundamental researches, difficulties in recognizing and identifying EDCs and high cost, which restraint the knowledge on them.
文摘Based on the fact that Fe toxicity which is usually characterized by leaf oranging and low yield canbe obviously subdued by application of Si or Mn due to counteraction between Fe and Si or Mn. A potexperiment was conducted with four treatments of CK, Si, Mn and Si+Mn to further study the effect ofcombined application of Si and Mn on rice growth on red earths. Water-soluble Si, Fe and Mn were measured,and electron probe was used to study Si, Mn, Fe and Ca in root cross sections. Combined application of Si andMn could increase water-soluble Si and Mn but reduce water-soluble Fe, thus being favorable for correctingFe toxicity. Electron probe study showed obvious differences of Si, Fe, Mn and Ca in rice roots betweenCK and the other three treatments. The combined application of Si and Mn could reduce leaf oranging andimprove rice growth. The Si+Mn treatment had a higher plant height, lower number of oranging leaves anda 25.0% higher rice yield than CK and showed a better effect on rice growth than the treatment of sole Si orMn.
基金Supported by National Natural Science Foundation of China(31371529)Science and Technology Development Program of Henan Province(162102110020)~~
文摘The aim of this study was to find out the effects of exogenous phenolic acids on soil microbes and enzymes in rhizosphere soil of adzuki bean. In the pot experiment of adzuki bean, phthalic and cinnamic acids were added at four concentrations, 0 (control), 0.1, 1 and 10 mmol/L, to investigate the changes in the mi- croflora and enzyme activities in rhizosphere soil of adzuki bean as well as relations between them. The results showed that both phthalic and cinnamic acids could inhibit the activities of soil enzymes, including catalase, sucrase, phosphatase and urease. Higher concentrations (10 mmol/L) of phthalic and cinnamic acids showed more significant effects. In addition, the application of phthalic and cinnamic acids reduced the populations of bacteria and actinomycetes and significantly increased the population of fungi. Correlations analysis showed that phosphatase activity had an extremely significant positive correlation with bacterial population, a significant positive correlation with actinomycete population, and a significant negative correlation with fungal population. Phthalic and cinnamic acids could result in imbalanced microbe compositions, reduce enzyme activities and present evident allelopathy in rhizosphere soil.
文摘Recent studies have uncovered two signaling pathways that activate the host innate immunity against viral infection. One of the pathways utilizes members of the Toll-like receptor (TLR) family to detect viruses that enter the endosome through endocytosis. The TLR pathway induces interferon production through several signaling proteins that ultimately lead to the activation of the transcription factors NF-kB, IRF3 and IRFT. The other antiviral pathway uses the RNA helicase RIG-Ⅰ as the receptor for intracellular viral double-stranded RNA. RIG-Ⅰ activates NF-kB and IRFs through the recently identified adaptor protein MAVS, a CARD domain containing protein that resides in the mitochondrial membrane. MAVS is essential for antiviral innate immunity, but it also serves as a target of Hepatitis C virus (HCV), which employs a viral protease to cleave MAVS off the mitochondria, thereby allowing HCV to escape the host immune system.
基金Under the auspices of the Key Innovation Program of Chinese Academy of Sciences(No.KZCX1-SW-19-4-01)the National Key Basic Research and Development Program of China(No.2004CB41850407)
文摘Ecotoxicity and bioavailability of cadmium (Cd) to the maize (Zea mays L.) and the soybean (Glycine max (L.) Merr.) were investigated by acute toxicity experiment in the laboratory with black soil. Ecotoxicity and bioavailability of Cd were quantified by calculating the median effective concentration (ECs0) and bioaccumulation factor (BAF). The measurement endpoints used were seed germination and seedling growth (shoot and root). The results showed that concentrations of Cd in the soil had adverse effect on the growth of roots and shoots. Seed germination was not the sensitive indicator for the ecotoxicity of Cd in the soil, while the growth of roots was the most sensitive measurement endpoint. Absorbability and transport of Cd in plants depended on the test crop species and Cd concentrations in the soil. The maize retains more Cd in its roots, while the soybean transports more Cd to the shoots from roots.