The eco-environmental vulnerability and underdevelopment of the agriculture in Southwest China would strengthen its disadvantage conditions further on the condition of arid climate change.It is necessary to deal with ...The eco-environmental vulnerability and underdevelopment of the agriculture in Southwest China would strengthen its disadvantage conditions further on the condition of arid climate change.It is necessary to deal with the relations between resource utilization and eco-environment finely and ascertain the adaptive principles on the dry valley agriculture to the arid climate change in order to change the extensive utilization of the special agricultural resources.The paper gave some adaptive countermeasures that develop modern rangeland husbandry,strengthening the special agriculture and agricultural industrialization,emphasis on the ecological agriculture development,constructing the extension system of water-saving modern agriculture,encouraging the service industry related to "agriculture,peasants and the countryside",constructing water utilization facilities,and exploiting the renewable energies.展开更多
The study investigated the streamflow response to the shrinking cryosphere under changing climate in the Lidder valley, Upper Indus Basin(UIB), Kashmir Himalayas. We used a combination of multitemporal satellite data ...The study investigated the streamflow response to the shrinking cryosphere under changing climate in the Lidder valley, Upper Indus Basin(UIB), Kashmir Himalayas. We used a combination of multitemporal satellite data and topographic maps to evaluate the changes in area, length and volume of the glaciers from 1962 to 2013. A total of 37 glaciers from the Lidder valley, with an area of 39.76 km^2 in 1962 were selected for research in this study. It was observed that the glaciers in the valley have lost ~28.89 ±0.1% of the area and ~19.65 ±0.069% of the volume during the last 51 years, with variable interdecadal recession rates. Geomorphic and climatic influences on the shrinking glacier resources were studied. 30-years temperature records(1980-2010) in the study area showed a significant increasing trend in all the seasons. However, the total annual precipitation during the same period showed a nonsignificant decreasing trend except during the late summer months(July, August and September), when the increasing trend is significant. The depletion of glaciers has led to the significant depletion of the streamflows under the changing climate in the valley. Summer streamflows(1971-2012) have increased significantly till mid-nineties but decreased significantly thereafter, suggesting that the tipping point of streamflow peak, due to the enhanced glacier-melt contribution under increasing global temperatures, may have been already reached in the basin. The observed glacier recession and climate change patterns, if continued in future, would further deplete the streamflows with serious implications on water supplies for different uses in the region.展开更多
AIM:To investigate prescribing pattern in low-dose aspirin users and physician awareness of preventing aspirin-induced gastrointestinal(GI) injury with combined protective medications.METHODS:A retrospective drug util...AIM:To investigate prescribing pattern in low-dose aspirin users and physician awareness of preventing aspirin-induced gastrointestinal(GI) injury with combined protective medications.METHODS:A retrospective drug utilization study was conducted in the 2nd Affiliated Hospital,School of Medicine,Zhejiang University.The hospital has 2300 beds and 2.5 million outpatient visits annually.Data mining was performed on all aspirin prescriptions for outpatients and emergency patients admitted in 2011.Concomitant use of proton-pump inhibitors(PPIs),histamine 2-receptor antagonists(H2RA) and mucoprotective drugs(MPs) were analyzed.A defined daily dose(DDD) methodology was applied to each MP.A further investigation was performed in aspirin users on combination use of GI injurious medicines [non-steoid anti-inflammatory drugs(NSAIDs),corticosteroids and clopidogrel and warfarin] or intestinal protective drugs(misoprostol,rebamipide,teprenone and gefarnate).Data of major bleeding episodes were derived from medical records and adverse drug reaction monitoring records.The annual incidence of major GI bleeding due to low-dose aspirin was estimated for outpatients.RESULTS:Prescriptions for aspirin users receiving PPIs,H2RA and MPs(n = 1039) accounted for only 3.46% of total aspirin prescriptions(n = 30 015).The ratios of coadministration of aspirin/PPI,aspirin/H2RA,aspirin/MP and aspirin/PPI/MP to the total aspirin prescriptions were 2.82%,0.12%,0.40% and 0.12%,respectively.No statistically significant difference was observed in age between patients not receiving any GI protective medications and patients receiving PPIs,H2RA or MPs.The combined medication of aspirin and PPI was used more frequently than that of aspirin and MPs(2.82% vs 0.40%,P < 0.05) and aspirin/H2RA(2.82% vs 0.12%,P < 0.05).The values of DDDs of MPs in descending order were as follows:gefarnate,hydrotalcite > teprenone > sucralfate oral suspension > L-glutamine and sodium gualenate granules > rebamipide > sucralfate chewable tablets.The ratio of MP plus aspirin prescriptions to the total MP prescriptions was as follows:rebamipide(0.47%),teprenone(0.91%),L-glutamine and sodium gualenate granules(0.92%),gefarnate(0.31%),hydrotalcite(1.00%) and sucralfate oral suspension(0.13%).Percentages of prescriptions containing aspirin and intestinal protective drugs among the total aspirin prescriptions were:rebamipide(0.010%),PPI/rebamipide(0.027%),teprenone(0.11%),PPI/teprenone(0.037%),gefarnate(0.017%),and PPI/gefarnate(0.013%).No prescriptions were found containing coadministration of aspirin and other NSAIDs.Among the 3196 prescriptions containing aspirin/clopidogrel,3088(96.6%) prescriptions did not contain any GI protective medicines.Of the 389 prescriptions containing aspirin/corticosteroids,236(60.7%) contained no GI protective medicines.None of the prescriptions using aspirin/warfarin(n = 22) contained GI protective medicines.Thirty-five patients were admitted to this hospital in 2011 because of acute hemorrhage of upper digestive tract induced by low-dose aspirin.The annual incidence rates of major GI bleeding were estimated at 0.25% for outpatients taking aspirin and 0.5% for outpatients taking aspirin/warfarin,respectively.CONCLUSION:The prescribing pattern of low-dose aspirin revealed a poor awareness of preventing GI injury with combined protective medications.Actions should be taken to address this issue.展开更多
AIM: To observe the efficacy of peg-interferon in the treatment of hepatitis delta virus (HDV) and to identify the factors that would be predictive of the sustained viral response (SVR). METHODS: This prospectiv...AIM: To observe the efficacy of peg-interferon in the treatment of hepatitis delta virus (HDV) and to identify the factors that would be predictive of the sustained viral response (SVR). METHODS: This prospective study was conducted in Medical Unit IV of the Liaquat University of Medi- cal and Health Sciences Hospital Jamshoro from June 2008 to September 2011. This study cohort included all patients of either sex who presented during this time with hepatitis B surface antigen positivity, hepa- titis B virus DNA 〉 20 000 IU/ml, serum glutamic py- ruvic transaminase (SGPT) 〉 2(upper limit of normal), HDV-RNA positivity with fibrosis stage ≥ 2. Informed consent was obtained from each of these individuals. Patients were diagnosed with hepatitis D on the ba- sis of detectable viral antibodies and the presence of HDV-RNA in their serum. A liver biopsy was performed in all cases and fibrosis staging was performed in ac- cordance with the METAVIR scoring system. All eligible patients were administered peg-interferon at a weekly dosage of 1.5 μg/kg body weight for 48 wk. HDV-RNA was assayed at the end of this treatment period and again at 24 wk later. A biochemical response was de- termined by a normalization of SGPT at the end of the treatment or during follow up. The end of treatment response was defined by a HDV-RNA negative status. A sustained virological response was defined by unde- tectable serum HDV-RNA at six months after the end of treatment. RESULTS: Among the 277 patients enrolled in our present study, 238 completed a course of peg-interfer- on therapy of which 180 (75.6%) were male and 58 (24.4%) female. Biochemical responses were achieved in 122/238 (51.3%) patients. End of treatment re- sponses were achieved in 71/238 (29.8%) cases. A SVR was achieved in 70 of these patients (29.4%). A strong association was found between the SVR and the end of treatment responses (P = 0.001), biochemical responses (P = 0.001) and the degree of fibrosis (P = 0.002). CONCLUSION: Peg-interferon therapy can induce re- mission in nearly one third of patients harboring HDV.展开更多
Underutilized plant species help to alleviate common food insufficiencies by providing alternative food supply. They also complement primary health care, furnishing raw materials where the cultivation of staple cereal...Underutilized plant species help to alleviate common food insufficiencies by providing alternative food supply. They also complement primary health care, furnishing raw materials where the cultivation of staple cereal crops is least feasible and health care is pursued indigenously. Research and promotion of extraction, utilization, and conservation of underutilized species lead to exploration of new staple crops and motivate people to consume in a sustainable manner. The present study describes the current status, uses, and management of underutilized plant species in Far West Nepal. The relative importance of 49 underutilized plant species was computed employing a Relative Importance (RI) technique. The use-values assigned to the species fall into six use-categories: beverage, fodder, food & edible, medicinal, vegetable and veterinary. A total of 22 species appeared in multiple use-categories, while the rest were characterized by a single use-category. Based on relative importance and frequency, Ficus semicordata, Debregesia longifolia, Girardinea diversifolia, Hydrocotyle nepalensis, Garuga pinnata, Aloe vera and Pyrus pashia offer the most potential for future. Underutilized plants proved important to folk medicine and food. These species persist because they remain useful to local people as means of subsistence, production, and primary health care. The findings are important so far as they point up the role of underutilized plants in national food security policy and health care, spelling out their potentialities and cross cutting relationships.展开更多
Past earthquakes have revealed that topographic features have significant impacts on the characteristics of ground motions,which may cause the amplification and de-amplification of input seismic waves.The topographic ...Past earthquakes have revealed that topographic features have significant impacts on the characteristics of ground motions,which may cause the amplification and de-amplification of input seismic waves.The topographic effect with the assumption of plane seismic waves on the seismic responses of bridges has been investigated in the existing literature;however,the influence of near-source topographic effects has not been thoroughly understood.The objective of this study is to numerically explore the near-source topographic effects on the seismic behaviors of an existing railway bridge crossing a symmetrical V-shaped canyon.The influence of the source of incident waves is estimated.Numerical results demonstrate that the topographic effects can noticeably amplify the seismic responses of the bridge.Compared to the bridge without crossing a canyon,the peak displacements of the girder,pier,and bearing in the case of the canyon crossing bridge increase by 15.2%,2.9%−14.5%,and 24.2%−229.6%,respectively.The piers at the illuminated side of the canyon experience larger seismic responses compared to the piers at the shaded side of the canyon due to the unequal motion amplitudes at each support.As the source-to-canyon distance increases,the seismic responses of the piers show an increasing trend.展开更多
AIM: To study the modulation of glutamate on post-ischemic intestinal and cerebral inflammatory responses in a ischemic and excitotoxic rat model.METHODS: Adult male rats were subjected to bilateral carotid artery occ...AIM: To study the modulation of glutamate on post-ischemic intestinal and cerebral inflammatory responses in a ischemic and excitotoxic rat model.METHODS: Adult male rats were subjected to bilateral carotid artery occlusion for 15 min and injection of monosodium glutamate intraperitoneally, to decapitate them at selected time points. Tumor necrosis factor alpha (TNF-α) level and nuclear factor kappa B (NF-κB) activity were determined by enzyme-linked immunosorbant assay (ELISA) and electrophoretic mobility shift assay (EMSA), respectively.Hemodynamic parameters were monitored continuously during the whole process of cerebral ischemia and reperfusion.RESULTS: Monosodium glutamate (MSG) treated rats displayed statistically significant high levels of TNF-α in cerebral and intestinal tissuess within the first 6 h of ischemia. The rats with cerebral ischemia showed a minor decrease of TNF-α production in cerebral and intestinal tissuess. The rats with cerebral ischemia and treated with MSG displayed statistically significant low levels of TNF-α in cerebral and intestinal tissues. These results correlated significantly with NF-κB production calculated at the same intervals. During experiment, the mean blood pressure and heart rates in all groups were stable.CONCLUSION: Glutamate is involved in the mechanism of intestinal and cerebral inflammation responses. The effects of glutamate on cerebral and intestinal inflammatory responses after ischemia are up-regulated at the transcriptional level,through the NF-κB signal transduction pathway.展开更多
AIM:To investigate whether carnitine deficiency is a risk factor during the development of diethylnitrosamine (DENA)-induced hepatic carcinogenesis. METHODS:A total of 60 male Wistar albino rats were divided into six ...AIM:To investigate whether carnitine deficiency is a risk factor during the development of diethylnitrosamine (DENA)-induced hepatic carcinogenesis. METHODS:A total of 60 male Wistar albino rats were divided into six groups with 10 animals in each group.Rats in group 1(control group)received a single intraperitoneal(i.p.)injection of normal saline. Animals in group 2(carnitine-supplemented group) were given L-carnitine(200 mg/kg per day)in drinking water for 8 wk.Animals in group 3(carnitine-depleted group)were given D-carnitine(200 mg/kg per day)and mildronate(200 mg/kg per day)in drinking water for 8 wk.Rats in group 4(DENA group)were injected with a single dose of DENA(200 mg/kg,i.p.)and 2 wk later received a single dose of carbon tetrachloride(2 mL/kg) by gavage as 1:1 dilution in corn oil.Animals in group 5(DENA-carnitine depleted group)received the same treatment as group 3 and group 4.Rats in group 6 (DENA-carnitine supplemented group)received the same treatment as group 2 and group 4.RESULTS:Administration of DENA resulted in a significant increase in alanine transaminase(ALT), gamma-glutamyl transferase(G-GT),alkaline phosphatase(ALP),total bilirubin,thiobarbituric acid reactive substances(TBARS)and total nitrate/ nitrite(NOx)and a significant decrease in reduced glutathione(GSH),glutathione peroxidase(GSHPx), catalase(CAT)and total carnitine content in liver tissues.In the carnitine-depleted rat model,DENA induced a dramatic increase in serum ALT,G-GT,ALP and total bilirubin,as well as a progressive reduction in total carnitine content in liver tissues.Interestingly, L-carnitine supplementation resulted in a complete reversal of the increase in liver enzymes,TBARS and NOx,and a decrease in total carnitine,GSH,GSHPx, and CAT induced by DENA,compared with the control values.Histopathological examination of liver tissues confirmed the biochemical data,where L-carnitine prevented DENA-induced hepatic carcinogenesis while D-carnitine-mildronate aggravated DENA-induced hepatic damage. CONCLUSION:Data from this study suggest for the first time that:(1)carnitine deficiency is a risk factor and should be viewed as a mechanism in DENA- induced hepatic carcinogenesis;(2)oxidative stress plays an important role but is not the only cause of DENA-induced hepatic carcinogenesis;and(3) long-term L-carnitine supplementation prevents the development of DENA-induced liver cancer.展开更多
The preparation and characterization of an immobilized L-glutamic decarboxylase (GDC) were studied. This work is to develop a sensitive method for the determination of L-glutamate using a new biosensor, which consists...The preparation and characterization of an immobilized L-glutamic decarboxylase (GDC) were studied. This work is to develop a sensitive method for the determination of L-glutamate using a new biosensor, which consists of an enzyme column reactor of GDC immobilized on a novel ion exchange resin (carboxymethyl-copolymer of allyl dextran and N.N?methylene-bisacrylamide CM-CADB) and ion analyzer coupled with a CO2 electrode. The conditions for the enzyme immobilization were optimized by the parameters: buffer composition and concentration, adsorption equilibration time, amount of enzyme, temperature, ionic strength and pH. The properties of the immobilized enzyme on CM-CADB were studied by investigating the initial rate of the enzyme reaction, the effect of various parameters on the immobilized GDC activity and its stability. An immobilized GDC enzyme column reactor matched with a flow injection system-ion analyzer coupled with CO2 electrode-data collection system made up the original form of the apparatus of biosensor for determining of L-glutamate acid. The limit of detection is 1.0×10-5 M. The linearity response is in the range of 5×10 -2-5×10 -5 M . The equation of linear regression of the calibration curve is y= 43.3x + 181.6 (y is the milli-volt of electrical potential response, x is the logarithm of the concentration of the substrate of L-glutamate acid). The correlation coefficient equals 0.99. The coefficient of variation equals 2.7%.展开更多
AIM: To investigate the role of reactive oxygen species (ROS) in ethanol-mediated cell death of polarized hepatic (WlF-B) cells.METHODS: In this work, WIF-B cultures were treated with pyrazole (inducer of cytoc...AIM: To investigate the role of reactive oxygen species (ROS) in ethanol-mediated cell death of polarized hepatic (WlF-B) cells.METHODS: In this work, WIF-B cultures were treated with pyrazole (inducer of cytochrome P4502E1, CYP2E1) and/or L-buthionine sulfoximine (BSO), a known inhibitor of hepatic glutathione (GSH), followed by evaluation of ROS production, antioxidant levels, and measures of cell injury (apoptosis and necrosis).RESULTS: The results revealed that ethanol treatment alone caused a significant two-fold increase in the activation of caspase-3 as well as a similar doubling in ROS. When the activity of the CYP2E1 was increased by pyrazole pretreatment, an additional two-fold elevation in ROS was detected. However, the CYP2EIrelated ROS elevation was not accompanied with a correlative increase in apoptotic cell injury, but rather was found to be associated with an increase in necrotic cell death. Interestingly, when the thiol status of the cells was manipulated using BSO, the ethanol-induced activation of caspase-3 was abrogated. Additionally, ethanol-treated cells displayed enhanced susceptibility to Fas-mediated apoptosis that was blocked by GSH depletion as a result of diminished caspase-8 activity.CONCLUSION: Apoptotic cell death induced as a consequence of ethanol metabolism is not completely dependent upon ROS status but is dependent on sustained GSH levels,展开更多
The ribosomal protein S29 also known as RPS29, is not only a component of the 40S subunit of ribosome, but also involved in embryonic development, oncogenesis and other pathologic conditions. However, rare commercial ...The ribosomal protein S29 also known as RPS29, is not only a component of the 40S subunit of ribosome, but also involved in embryonic development, oncogenesis and other pathologic conditions. However, rare commercial antibody against RPS29 restricts the discovery of precise physiological and pathological function of this protein. In this study, the whole RPS29 gene was inserted into plasmid pGEX-6p-1 to express glutathione's transferase (GST) fusion proteins in Escherichia eoli (E. coli) strain BL21. High yields of soluble recombinant proteins were obtained. Mice were immunized with the recombinant RPS29 protein. The serum from the immunized mice could specially react with purified recombinant RPS29 proteins and native RPS29 proteins in CCE cells by western blotting, immunofluorescence staining and flow cytometric analysis. Further more the polyclonal antibodies also reacted specifically with human cell strain ECV304, which showed typical cytoplasmatic fluorescence. The polyclonal antibodies we prepared would be an available tool for studying the roles of RPS29 in embryonic development and human diseases.展开更多
Tailings impoundments can potentially collapse due to damage caused by earthquakes,which has frequently occurred around the world.This study takes the proposed valley type tailings impoundment in Yunnan as the researc...Tailings impoundments can potentially collapse due to damage caused by earthquakes,which has frequently occurred around the world.This study takes the proposed valley type tailings impoundment in Yunnan as the research object to analyze the dynamic response behavior under earthquake action with both numerical simulation and physical model test(1:300).The results of both tests show that the dynamic response of the valley type tailings impoundment is characterized by"medium stiffness effect",in other words,in a certain range,the"softer"the unsaturated tailings sand is,the more energy it can dissipate,which leads the decrease of the value of the acceleration amplification factor.In addition,the peak acceleration of the monitoring points increases with the vertical elevation,which indicates that the"elevation amplification effect"exists in the tailings impoundment dynamic response.The middle part of the outer side of the raised embankment reacts more sensitive than the crest,which is similar to the slope dynamic response.The starter dam reacts sensitively under the earthquake excitation,which should be given more attention during the seismic design.The dynamic response rules reflected by the numerical simulation are consistent with the results monitored on the physical model test,although there are some differences between their values.The dynamic response rules of the valley type tailings impoundment can provide basis for the design of the similar projects in this region.展开更多
Heavy metal pollution can affect the immune capability of organisms. We evaluated the effect of cadmium (Cd) on the defense responses of the Pacific oyster Crassostrea gigas to Listonella anguillarum challenge. The ...Heavy metal pollution can affect the immune capability of organisms. We evaluated the effect of cadmium (Cd) on the defense responses of the Pacific oyster Crassostrea gigas to Listonella anguillarum challenge. The activities of several important defensive enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GPx), acid phosphatase (ACP), Na+, K+-ATPase in gills and hepatopancreas, and phenoloxidase-like (POL) enzyme in hemolymph were assayed. In addition, the expression levels of several genes, including heat shock protein 90 (IrtSP9~)), metallothionein (MT), and bactericidal/permeability increasing (BPI) protein were quantified by fluorescent quantitative PCR. The enzyme activities of SOD, ACP, POL, and GPx in hepatopancreas, and the expression of HSP90 were down-regulated, whereas GPx activity in the gill, Na+, K+-ATPase activities in both tissues, and MT expression was increased in Cd- exposed oysters post L. anguillarum challenge. However, BPI expression was not significantly altered by co-stress of L. anguillarum infection and cadmium exposure. Our results suggest that cadmium exposure alters the oysters' immune responses and energy metabolism following vibrio infection.展开更多
This study investigated the inductive effect ofAlexandrium tamarense, a toxic dinoflagellate producing paralytic shell- fish poison, on oxidative stress and apoptosis in hepatopancreas of Chinese shrimp, Fenneropenaeu...This study investigated the inductive effect ofAlexandrium tamarense, a toxic dinoflagellate producing paralytic shell- fish poison, on oxidative stress and apoptosis in hepatopancreas of Chinese shrimp, Fenneropenaeus chinensis. The individuals of E chinensis were exposed to 200 and 1000 cells mL-1 of A. tamarense with their superoxide dismutase (SOD), glutathione S-transferase (GST) activities, malonyldialdehyde (MDA) concentration, and caspase gene (FcCasp) expression in hepatopancreas determined at 12, 24, 48, 72 and 96 h. In addition, apoptosis in hepatopancreas of E chinensis at 96 h after exposure was determined through terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. The hepatopancreatic SOD and GST activities of F. chinensis exposed to 1000 cells mL-1 ofA. tamarense showed a bell-shaped response to exposure time. The hepatopancreatic MDA concentration ofF. chinensis exposed to 1000 cellsmL-1 ofA. tamarense increased gradually from 48 to 96h, and such a trend corresponded to the decrease of GST activity. The hepatopancreatic FcCasp transcript abundance of F. chinensis exposed to 1000 cells mL-1 ofA. tamarense was positively and linearly correlated to MDA concentration. Results of TUNEL assay showed that exposure to 1000 cells mL-1 of A. tamarense induced apoptosis in the hepatopancreas of E chinensis. Our study revealed that A. tamarense exposure influenced the antioxidative status ofF. chinensis and caused lipid peroxidation and apoptosis in the hepatopancreas of shrimp.展开更多
Organic pollution is a serious environmental problem in coastal areas and it is important to establish quantitative methods for monitoring this pollution. This study screened a series of sensitive biomarkers to constr...Organic pollution is a serious environmental problem in coastal areas and it is important to establish quantitative methods for monitoring this pollution. This study screened a series of sensitive biomarkers to construct an integrated biomarker response (IBR) index using Mytilus edulis. Mussels were exposed to the polycyclic aromatic hydrocarbon anthracene trader controlled laboratory conditions and the activities of components of the glutathione antioxidant system, and the concentrations of oxidative-damage markers, were measured in the gills and digestive glands. Anthracene exposure resulted in increased levels of malondialdehyde (MDA) and superoxide radicals (O2-·), indicating that oxidative damage had occurred. Correspondingly, anthracene exposure induced increased activities of glutathione S-transferase (GST), glutathione peroxidase (GPx) and reduced glutathione (GSH) in digestive glands, and GPx and glutathione reductase (GR) in gills, consistent with stimulation of the antioxidant system. A field experiment was set up, in which mussels from a relatively clean area were transplanted to a contaminated site. One month later, the activities of GST, GPx and GR had increased in several tissues, particularly in the digestive glands. Based on the laboratory experiment, an IBR, which showed a positive relationship with anthracene exposure, was constructed. The IBR is suggested to be a potentially useful tool for assessing anthracene pollution.展开更多
To assess the toxicity of heavy metal pollution to marine intertidal shellfish, enzymatic responses and lipid peroxidation were investigated in the clam Mactra vereformis exposed to cadmium under laboratory conditions...To assess the toxicity of heavy metal pollution to marine intertidal shellfish, enzymatic responses and lipid peroxidation were investigated in the clam Mactra vereformis exposed to cadmium under laboratory conditions. Three antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase, GPx), two immune defense enzymes (acid phosphatase, ACP; alkaline phosphatase, ALP), and one lipid peroxidation product (malondialdehyde, MDA) were measured in the gills and the hepatopancreas of the clam exposed to 0, 25, 75, and 125 μg/L cadmium for 0, 1, 3, 5, and 7 d. The results show that the concentrations of antioxidant enzymes in the organs soared to a peak value on the first day and then decreased afterwards in most cases. CAT and GPx activities in the hepatopancreas were higher than in the gills, but the SOD activity was lower in the hepatopancreas. ACP activity was unchanged until Day 3 in the hepatopancreas and until Day 5 in gills, when it began to increase. ALP activity showed no significant relationship with Cd treatment. MDA concentrations increased in the two tissues after Cd exposure, peaked on Day 3 in gills, and on Day 5 in hepatopancreas. These observations show that changes in the activities of antioxidant enzymes and ACP reflect the time course of oxidative stress in the clam caused by Cd, and could be used as potential biomarkers for ecotoxicological bioassays of heavy metals.展开更多
waste dam is one of the most important infrastructures in the project of valley sanitary landfill. On one hand, it forms the landfill capacity required. On the other hand, it improves the slope stability of waste body...waste dam is one of the most important infrastructures in the project of valley sanitary landfill. On one hand, it forms the landfill capacity required. On the other hand, it improves the slope stability of waste body. Consequently, I think it is very significant to maintain the stability of waste dana for the whole sanitary landfill. Combining with a project example, aiming at the special geological conditions, we have made three plans of waste dam structure, calculation and analysis comparison respectively. Reinforced concrete frame waste dam is highlighted in the project for its advantages, smoothly solving the three problems in the engineering.展开更多
基金funded by Arid Meteorology Research Fund(IAM201007)Research Fund of Chengdu University of Information Technology(KYTZ201030)National Natural Science Foundation Project(40971304)~~
文摘The eco-environmental vulnerability and underdevelopment of the agriculture in Southwest China would strengthen its disadvantage conditions further on the condition of arid climate change.It is necessary to deal with the relations between resource utilization and eco-environment finely and ascertain the adaptive principles on the dry valley agriculture to the arid climate change in order to change the extensive utilization of the special agricultural resources.The paper gave some adaptive countermeasures that develop modern rangeland husbandry,strengthening the special agriculture and agricultural industrialization,emphasis on the ecological agriculture development,constructing the extension system of water-saving modern agriculture,encouraging the service industry related to "agriculture,peasants and the countryside",constructing water utilization facilities,and exploiting the renewable energies.
基金part of the Department of Science and Technology(DST),Government of India sponsored national research project titled“Himalayan Cryosphere:Science and Society”
文摘The study investigated the streamflow response to the shrinking cryosphere under changing climate in the Lidder valley, Upper Indus Basin(UIB), Kashmir Himalayas. We used a combination of multitemporal satellite data and topographic maps to evaluate the changes in area, length and volume of the glaciers from 1962 to 2013. A total of 37 glaciers from the Lidder valley, with an area of 39.76 km^2 in 1962 were selected for research in this study. It was observed that the glaciers in the valley have lost ~28.89 ±0.1% of the area and ~19.65 ±0.069% of the volume during the last 51 years, with variable interdecadal recession rates. Geomorphic and climatic influences on the shrinking glacier resources were studied. 30-years temperature records(1980-2010) in the study area showed a significant increasing trend in all the seasons. However, the total annual precipitation during the same period showed a nonsignificant decreasing trend except during the late summer months(July, August and September), when the increasing trend is significant. The depletion of glaciers has led to the significant depletion of the streamflows under the changing climate in the valley. Summer streamflows(1971-2012) have increased significantly till mid-nineties but decreased significantly thereafter, suggesting that the tipping point of streamflow peak, due to the enhanced glacier-melt contribution under increasing global temperatures, may have been already reached in the basin. The observed glacier recession and climate change patterns, if continued in future, would further deplete the streamflows with serious implications on water supplies for different uses in the region.
基金Supported by Zhejiang Provincial Bureau of Health,No. 2012KYA090Zhejiang Provincial Bureau of Education, No.20070227
文摘AIM:To investigate prescribing pattern in low-dose aspirin users and physician awareness of preventing aspirin-induced gastrointestinal(GI) injury with combined protective medications.METHODS:A retrospective drug utilization study was conducted in the 2nd Affiliated Hospital,School of Medicine,Zhejiang University.The hospital has 2300 beds and 2.5 million outpatient visits annually.Data mining was performed on all aspirin prescriptions for outpatients and emergency patients admitted in 2011.Concomitant use of proton-pump inhibitors(PPIs),histamine 2-receptor antagonists(H2RA) and mucoprotective drugs(MPs) were analyzed.A defined daily dose(DDD) methodology was applied to each MP.A further investigation was performed in aspirin users on combination use of GI injurious medicines [non-steoid anti-inflammatory drugs(NSAIDs),corticosteroids and clopidogrel and warfarin] or intestinal protective drugs(misoprostol,rebamipide,teprenone and gefarnate).Data of major bleeding episodes were derived from medical records and adverse drug reaction monitoring records.The annual incidence of major GI bleeding due to low-dose aspirin was estimated for outpatients.RESULTS:Prescriptions for aspirin users receiving PPIs,H2RA and MPs(n = 1039) accounted for only 3.46% of total aspirin prescriptions(n = 30 015).The ratios of coadministration of aspirin/PPI,aspirin/H2RA,aspirin/MP and aspirin/PPI/MP to the total aspirin prescriptions were 2.82%,0.12%,0.40% and 0.12%,respectively.No statistically significant difference was observed in age between patients not receiving any GI protective medications and patients receiving PPIs,H2RA or MPs.The combined medication of aspirin and PPI was used more frequently than that of aspirin and MPs(2.82% vs 0.40%,P < 0.05) and aspirin/H2RA(2.82% vs 0.12%,P < 0.05).The values of DDDs of MPs in descending order were as follows:gefarnate,hydrotalcite > teprenone > sucralfate oral suspension > L-glutamine and sodium gualenate granules > rebamipide > sucralfate chewable tablets.The ratio of MP plus aspirin prescriptions to the total MP prescriptions was as follows:rebamipide(0.47%),teprenone(0.91%),L-glutamine and sodium gualenate granules(0.92%),gefarnate(0.31%),hydrotalcite(1.00%) and sucralfate oral suspension(0.13%).Percentages of prescriptions containing aspirin and intestinal protective drugs among the total aspirin prescriptions were:rebamipide(0.010%),PPI/rebamipide(0.027%),teprenone(0.11%),PPI/teprenone(0.037%),gefarnate(0.017%),and PPI/gefarnate(0.013%).No prescriptions were found containing coadministration of aspirin and other NSAIDs.Among the 3196 prescriptions containing aspirin/clopidogrel,3088(96.6%) prescriptions did not contain any GI protective medicines.Of the 389 prescriptions containing aspirin/corticosteroids,236(60.7%) contained no GI protective medicines.None of the prescriptions using aspirin/warfarin(n = 22) contained GI protective medicines.Thirty-five patients were admitted to this hospital in 2011 because of acute hemorrhage of upper digestive tract induced by low-dose aspirin.The annual incidence rates of major GI bleeding were estimated at 0.25% for outpatients taking aspirin and 0.5% for outpatients taking aspirin/warfarin,respectively.CONCLUSION:The prescribing pattern of low-dose aspirin revealed a poor awareness of preventing GI injury with combined protective medications.Actions should be taken to address this issue.
基金Supported by Hepatitis Prevention and Control Program Sindh,Pakistan Chief Minister's initiative,a government organization provided peg-interferon treatment to patients for 48 wk free of cost
文摘AIM: To observe the efficacy of peg-interferon in the treatment of hepatitis delta virus (HDV) and to identify the factors that would be predictive of the sustained viral response (SVR). METHODS: This prospective study was conducted in Medical Unit IV of the Liaquat University of Medi- cal and Health Sciences Hospital Jamshoro from June 2008 to September 2011. This study cohort included all patients of either sex who presented during this time with hepatitis B surface antigen positivity, hepa- titis B virus DNA 〉 20 000 IU/ml, serum glutamic py- ruvic transaminase (SGPT) 〉 2(upper limit of normal), HDV-RNA positivity with fibrosis stage ≥ 2. Informed consent was obtained from each of these individuals. Patients were diagnosed with hepatitis D on the ba- sis of detectable viral antibodies and the presence of HDV-RNA in their serum. A liver biopsy was performed in all cases and fibrosis staging was performed in ac- cordance with the METAVIR scoring system. All eligible patients were administered peg-interferon at a weekly dosage of 1.5 μg/kg body weight for 48 wk. HDV-RNA was assayed at the end of this treatment period and again at 24 wk later. A biochemical response was de- termined by a normalization of SGPT at the end of the treatment or during follow up. The end of treatment response was defined by a HDV-RNA negative status. A sustained virological response was defined by unde- tectable serum HDV-RNA at six months after the end of treatment. RESULTS: Among the 277 patients enrolled in our present study, 238 completed a course of peg-interfer- on therapy of which 180 (75.6%) were male and 58 (24.4%) female. Biochemical responses were achieved in 122/238 (51.3%) patients. End of treatment re- sponses were achieved in 71/238 (29.8%) cases. A SVR was achieved in 70 of these patients (29.4%). A strong association was found between the SVR and the end of treatment responses (P = 0.001), biochemical responses (P = 0.001) and the degree of fibrosis (P = 0.002). CONCLUSION: Peg-interferon therapy can induce re- mission in nearly one third of patients harboring HDV.
文摘Underutilized plant species help to alleviate common food insufficiencies by providing alternative food supply. They also complement primary health care, furnishing raw materials where the cultivation of staple cereal crops is least feasible and health care is pursued indigenously. Research and promotion of extraction, utilization, and conservation of underutilized species lead to exploration of new staple crops and motivate people to consume in a sustainable manner. The present study describes the current status, uses, and management of underutilized plant species in Far West Nepal. The relative importance of 49 underutilized plant species was computed employing a Relative Importance (RI) technique. The use-values assigned to the species fall into six use-categories: beverage, fodder, food & edible, medicinal, vegetable and veterinary. A total of 22 species appeared in multiple use-categories, while the rest were characterized by a single use-category. Based on relative importance and frequency, Ficus semicordata, Debregesia longifolia, Girardinea diversifolia, Hydrocotyle nepalensis, Garuga pinnata, Aloe vera and Pyrus pashia offer the most potential for future. Underutilized plants proved important to folk medicine and food. These species persist because they remain useful to local people as means of subsistence, production, and primary health care. The findings are important so far as they point up the role of underutilized plants in national food security policy and health care, spelling out their potentialities and cross cutting relationships.
基金Projects(51908123,51678140,U1934205)supported by the National Natural Science Foundation of ChinaProjects(BK20190370,BK20180383) supported by the Natural Science Foundation of Jiangsu Province,China+1 种基金Project(18KJA580005) supported by the Natural Science Foundation of Jiangsu Higher Education Institutions of ChinaProject(KYY2019096(19-21)) supported by the Science and Technology Research Plan of China Railway Eryuan Engineering Group Corporation。
文摘Past earthquakes have revealed that topographic features have significant impacts on the characteristics of ground motions,which may cause the amplification and de-amplification of input seismic waves.The topographic effect with the assumption of plane seismic waves on the seismic responses of bridges has been investigated in the existing literature;however,the influence of near-source topographic effects has not been thoroughly understood.The objective of this study is to numerically explore the near-source topographic effects on the seismic behaviors of an existing railway bridge crossing a symmetrical V-shaped canyon.The influence of the source of incident waves is estimated.Numerical results demonstrate that the topographic effects can noticeably amplify the seismic responses of the bridge.Compared to the bridge without crossing a canyon,the peak displacements of the girder,pier,and bearing in the case of the canyon crossing bridge increase by 15.2%,2.9%−14.5%,and 24.2%−229.6%,respectively.The piers at the illuminated side of the canyon experience larger seismic responses compared to the piers at the shaded side of the canyon due to the unequal motion amplitudes at each support.As the source-to-canyon distance increases,the seismic responses of the piers show an increasing trend.
文摘AIM: To study the modulation of glutamate on post-ischemic intestinal and cerebral inflammatory responses in a ischemic and excitotoxic rat model.METHODS: Adult male rats were subjected to bilateral carotid artery occlusion for 15 min and injection of monosodium glutamate intraperitoneally, to decapitate them at selected time points. Tumor necrosis factor alpha (TNF-α) level and nuclear factor kappa B (NF-κB) activity were determined by enzyme-linked immunosorbant assay (ELISA) and electrophoretic mobility shift assay (EMSA), respectively.Hemodynamic parameters were monitored continuously during the whole process of cerebral ischemia and reperfusion.RESULTS: Monosodium glutamate (MSG) treated rats displayed statistically significant high levels of TNF-α in cerebral and intestinal tissuess within the first 6 h of ischemia. The rats with cerebral ischemia showed a minor decrease of TNF-α production in cerebral and intestinal tissuess. The rats with cerebral ischemia and treated with MSG displayed statistically significant low levels of TNF-α in cerebral and intestinal tissues. These results correlated significantly with NF-κB production calculated at the same intervals. During experiment, the mean blood pressure and heart rates in all groups were stable.CONCLUSION: Glutamate is involved in the mechanism of intestinal and cerebral inflammation responses. The effects of glutamate on cerebral and intestinal inflammatory responses after ischemia are up-regulated at the transcriptional level,through the NF-κB signal transduction pathway.
基金Supported by Operating grant from Research Center,Collegeof Pharmacy,King Saud University(CPRC 207)
文摘AIM:To investigate whether carnitine deficiency is a risk factor during the development of diethylnitrosamine (DENA)-induced hepatic carcinogenesis. METHODS:A total of 60 male Wistar albino rats were divided into six groups with 10 animals in each group.Rats in group 1(control group)received a single intraperitoneal(i.p.)injection of normal saline. Animals in group 2(carnitine-supplemented group) were given L-carnitine(200 mg/kg per day)in drinking water for 8 wk.Animals in group 3(carnitine-depleted group)were given D-carnitine(200 mg/kg per day)and mildronate(200 mg/kg per day)in drinking water for 8 wk.Rats in group 4(DENA group)were injected with a single dose of DENA(200 mg/kg,i.p.)and 2 wk later received a single dose of carbon tetrachloride(2 mL/kg) by gavage as 1:1 dilution in corn oil.Animals in group 5(DENA-carnitine depleted group)received the same treatment as group 3 and group 4.Rats in group 6 (DENA-carnitine supplemented group)received the same treatment as group 2 and group 4.RESULTS:Administration of DENA resulted in a significant increase in alanine transaminase(ALT), gamma-glutamyl transferase(G-GT),alkaline phosphatase(ALP),total bilirubin,thiobarbituric acid reactive substances(TBARS)and total nitrate/ nitrite(NOx)and a significant decrease in reduced glutathione(GSH),glutathione peroxidase(GSHPx), catalase(CAT)and total carnitine content in liver tissues.In the carnitine-depleted rat model,DENA induced a dramatic increase in serum ALT,G-GT,ALP and total bilirubin,as well as a progressive reduction in total carnitine content in liver tissues.Interestingly, L-carnitine supplementation resulted in a complete reversal of the increase in liver enzymes,TBARS and NOx,and a decrease in total carnitine,GSH,GSHPx, and CAT induced by DENA,compared with the control values.Histopathological examination of liver tissues confirmed the biochemical data,where L-carnitine prevented DENA-induced hepatic carcinogenesis while D-carnitine-mildronate aggravated DENA-induced hepatic damage. CONCLUSION:Data from this study suggest for the first time that:(1)carnitine deficiency is a risk factor and should be viewed as a mechanism in DENA- induced hepatic carcinogenesis;(2)oxidative stress plays an important role but is not the only cause of DENA-induced hepatic carcinogenesis;and(3) long-term L-carnitine supplementation prevents the development of DENA-induced liver cancer.
基金The Applied Fundamental Foundation of Jiangsu province P. R. China. Contract No BJ98041.
文摘The preparation and characterization of an immobilized L-glutamic decarboxylase (GDC) were studied. This work is to develop a sensitive method for the determination of L-glutamate using a new biosensor, which consists of an enzyme column reactor of GDC immobilized on a novel ion exchange resin (carboxymethyl-copolymer of allyl dextran and N.N?methylene-bisacrylamide CM-CADB) and ion analyzer coupled with a CO2 electrode. The conditions for the enzyme immobilization were optimized by the parameters: buffer composition and concentration, adsorption equilibration time, amount of enzyme, temperature, ionic strength and pH. The properties of the immobilized enzyme on CM-CADB were studied by investigating the initial rate of the enzyme reaction, the effect of various parameters on the immobilized GDC activity and its stability. An immobilized GDC enzyme column reactor matched with a flow injection system-ion analyzer coupled with CO2 electrode-data collection system made up the original form of the apparatus of biosensor for determining of L-glutamate acid. The limit of detection is 1.0×10-5 M. The linearity response is in the range of 5×10 -2-5×10 -5 M . The equation of linear regression of the calibration curve is y= 43.3x + 181.6 (y is the milli-volt of electrical potential response, x is the logarithm of the concentration of the substrate of L-glutamate acid). The correlation coefficient equals 0.99. The coefficient of variation equals 2.7%.
基金Supported by The National Institute on Alcohol Abuse and Alcoholism and by the Department of Veterans Affairs
文摘AIM: To investigate the role of reactive oxygen species (ROS) in ethanol-mediated cell death of polarized hepatic (WlF-B) cells.METHODS: In this work, WIF-B cultures were treated with pyrazole (inducer of cytochrome P4502E1, CYP2E1) and/or L-buthionine sulfoximine (BSO), a known inhibitor of hepatic glutathione (GSH), followed by evaluation of ROS production, antioxidant levels, and measures of cell injury (apoptosis and necrosis).RESULTS: The results revealed that ethanol treatment alone caused a significant two-fold increase in the activation of caspase-3 as well as a similar doubling in ROS. When the activity of the CYP2E1 was increased by pyrazole pretreatment, an additional two-fold elevation in ROS was detected. However, the CYP2EIrelated ROS elevation was not accompanied with a correlative increase in apoptotic cell injury, but rather was found to be associated with an increase in necrotic cell death. Interestingly, when the thiol status of the cells was manipulated using BSO, the ethanol-induced activation of caspase-3 was abrogated. Additionally, ethanol-treated cells displayed enhanced susceptibility to Fas-mediated apoptosis that was blocked by GSH depletion as a result of diminished caspase-8 activity.CONCLUSION: Apoptotic cell death induced as a consequence of ethanol metabolism is not completely dependent upon ROS status but is dependent on sustained GSH levels,
基金Supported by the National Natural Science Foundation of China(30800983,30700418 and 30972596)the Natural Science Foundation of Chongqing(2008BB5113 and 2009BB5015) the Scientific Research Foundation of Third Military Medical University(2009XHG03 and 2009XYY04)
文摘The ribosomal protein S29 also known as RPS29, is not only a component of the 40S subunit of ribosome, but also involved in embryonic development, oncogenesis and other pathologic conditions. However, rare commercial antibody against RPS29 restricts the discovery of precise physiological and pathological function of this protein. In this study, the whole RPS29 gene was inserted into plasmid pGEX-6p-1 to express glutathione's transferase (GST) fusion proteins in Escherichia eoli (E. coli) strain BL21. High yields of soluble recombinant proteins were obtained. Mice were immunized with the recombinant RPS29 protein. The serum from the immunized mice could specially react with purified recombinant RPS29 proteins and native RPS29 proteins in CCE cells by western blotting, immunofluorescence staining and flow cytometric analysis. Further more the polyclonal antibodies also reacted specifically with human cell strain ECV304, which showed typical cytoplasmatic fluorescence. The polyclonal antibodies we prepared would be an available tool for studying the roles of RPS29 in embryonic development and human diseases.
基金financially supported by project (Grant NO. U1502232, U1033601)-National Science Foundation of China-Yunnan Joint Fundproject (Grant NO. 20135314110005)-Research Fund for the Doctoral Program of Higher Education of China
文摘Tailings impoundments can potentially collapse due to damage caused by earthquakes,which has frequently occurred around the world.This study takes the proposed valley type tailings impoundment in Yunnan as the research object to analyze the dynamic response behavior under earthquake action with both numerical simulation and physical model test(1:300).The results of both tests show that the dynamic response of the valley type tailings impoundment is characterized by"medium stiffness effect",in other words,in a certain range,the"softer"the unsaturated tailings sand is,the more energy it can dissipate,which leads the decrease of the value of the acceleration amplification factor.In addition,the peak acceleration of the monitoring points increases with the vertical elevation,which indicates that the"elevation amplification effect"exists in the tailings impoundment dynamic response.The middle part of the outer side of the raised embankment reacts more sensitive than the crest,which is similar to the slope dynamic response.The starter dam reacts sensitively under the earthquake excitation,which should be given more attention during the seismic design.The dynamic response rules reflected by the numerical simulation are consistent with the results monitored on the physical model test,although there are some differences between their values.The dynamic response rules of the valley type tailings impoundment can provide basis for the design of the similar projects in this region.
基金Supported by the 100 Talents Program of Chinese Academy of Sciencesthe Development Plan of Science and Technology in Shandong Province(No.2012GGA06032)the Key Deployment Program of Chinese Academy of Sciences(No.KZZD-EW-14-03)
文摘Heavy metal pollution can affect the immune capability of organisms. We evaluated the effect of cadmium (Cd) on the defense responses of the Pacific oyster Crassostrea gigas to Listonella anguillarum challenge. The activities of several important defensive enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GPx), acid phosphatase (ACP), Na+, K+-ATPase in gills and hepatopancreas, and phenoloxidase-like (POL) enzyme in hemolymph were assayed. In addition, the expression levels of several genes, including heat shock protein 90 (IrtSP9~)), metallothionein (MT), and bactericidal/permeability increasing (BPI) protein were quantified by fluorescent quantitative PCR. The enzyme activities of SOD, ACP, POL, and GPx in hepatopancreas, and the expression of HSP90 were down-regulated, whereas GPx activity in the gill, Na+, K+-ATPase activities in both tissues, and MT expression was increased in Cd- exposed oysters post L. anguillarum challenge. However, BPI expression was not significantly altered by co-stress of L. anguillarum infection and cadmium exposure. Our results suggest that cadmium exposure alters the oysters' immune responses and energy metabolism following vibrio infection.
基金supported by Earmarked Fund for Modern Agro-industry Technology Research System of China (Grant No. CARS-47)Special Fund for Agroscientific Research in the Public Interest of China (Grant No. 201103034)the National ‘863’ Project of China (Grant No. 2012AA10A409)
文摘This study investigated the inductive effect ofAlexandrium tamarense, a toxic dinoflagellate producing paralytic shell- fish poison, on oxidative stress and apoptosis in hepatopancreas of Chinese shrimp, Fenneropenaeus chinensis. The individuals of E chinensis were exposed to 200 and 1000 cells mL-1 of A. tamarense with their superoxide dismutase (SOD), glutathione S-transferase (GST) activities, malonyldialdehyde (MDA) concentration, and caspase gene (FcCasp) expression in hepatopancreas determined at 12, 24, 48, 72 and 96 h. In addition, apoptosis in hepatopancreas of E chinensis at 96 h after exposure was determined through terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. The hepatopancreatic SOD and GST activities of F. chinensis exposed to 1000 cells mL-1 ofA. tamarense showed a bell-shaped response to exposure time. The hepatopancreatic MDA concentration ofF. chinensis exposed to 1000 cellsmL-1 ofA. tamarense increased gradually from 48 to 96h, and such a trend corresponded to the decrease of GST activity. The hepatopancreatic FcCasp transcript abundance of F. chinensis exposed to 1000 cells mL-1 ofA. tamarense was positively and linearly correlated to MDA concentration. Results of TUNEL assay showed that exposure to 1000 cells mL-1 of A. tamarense induced apoptosis in the hepatopancreas of E chinensis. Our study revealed that A. tamarense exposure influenced the antioxidative status ofF. chinensis and caused lipid peroxidation and apoptosis in the hepatopancreas of shrimp.
基金Supported by the Joint Funds of National Natural Science Foundation of ChinaMarine Science Research Center of the People’s Government of Shandong Province(No.U1406403)
文摘Organic pollution is a serious environmental problem in coastal areas and it is important to establish quantitative methods for monitoring this pollution. This study screened a series of sensitive biomarkers to construct an integrated biomarker response (IBR) index using Mytilus edulis. Mussels were exposed to the polycyclic aromatic hydrocarbon anthracene trader controlled laboratory conditions and the activities of components of the glutathione antioxidant system, and the concentrations of oxidative-damage markers, were measured in the gills and digestive glands. Anthracene exposure resulted in increased levels of malondialdehyde (MDA) and superoxide radicals (O2-·), indicating that oxidative damage had occurred. Correspondingly, anthracene exposure induced increased activities of glutathione S-transferase (GST), glutathione peroxidase (GPx) and reduced glutathione (GSH) in digestive glands, and GPx and glutathione reductase (GR) in gills, consistent with stimulation of the antioxidant system. A field experiment was set up, in which mussels from a relatively clean area were transplanted to a contaminated site. One month later, the activities of GST, GPx and GR had increased in several tissues, particularly in the digestive glands. Based on the laboratory experiment, an IBR, which showed a positive relationship with anthracene exposure, was constructed. The IBR is suggested to be a potentially useful tool for assessing anthracene pollution.
基金Supported by the National Basic Research Program of China (973 Program) (No. 2007CB407305)the Tianjin Program for Marine Development by Reliance on Science and Technology (No. kx2010-4)+2 种基金the National Marine Public Welfare Research Project of China (No. 200805069)the Natural Science Fundation for Creative Research Groups (No. 40821004)the Knowledge Innovation Key Projects of Chinese Academy of Sciences (No. KZCX2-YW-Q07-03)
文摘To assess the toxicity of heavy metal pollution to marine intertidal shellfish, enzymatic responses and lipid peroxidation were investigated in the clam Mactra vereformis exposed to cadmium under laboratory conditions. Three antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase, GPx), two immune defense enzymes (acid phosphatase, ACP; alkaline phosphatase, ALP), and one lipid peroxidation product (malondialdehyde, MDA) were measured in the gills and the hepatopancreas of the clam exposed to 0, 25, 75, and 125 μg/L cadmium for 0, 1, 3, 5, and 7 d. The results show that the concentrations of antioxidant enzymes in the organs soared to a peak value on the first day and then decreased afterwards in most cases. CAT and GPx activities in the hepatopancreas were higher than in the gills, but the SOD activity was lower in the hepatopancreas. ACP activity was unchanged until Day 3 in the hepatopancreas and until Day 5 in gills, when it began to increase. ALP activity showed no significant relationship with Cd treatment. MDA concentrations increased in the two tissues after Cd exposure, peaked on Day 3 in gills, and on Day 5 in hepatopancreas. These observations show that changes in the activities of antioxidant enzymes and ACP reflect the time course of oxidative stress in the clam caused by Cd, and could be used as potential biomarkers for ecotoxicological bioassays of heavy metals.
文摘waste dam is one of the most important infrastructures in the project of valley sanitary landfill. On one hand, it forms the landfill capacity required. On the other hand, it improves the slope stability of waste body. Consequently, I think it is very significant to maintain the stability of waste dana for the whole sanitary landfill. Combining with a project example, aiming at the special geological conditions, we have made three plans of waste dam structure, calculation and analysis comparison respectively. Reinforced concrete frame waste dam is highlighted in the project for its advantages, smoothly solving the three problems in the engineering.