环氧树脂单体双酚A二缩水甘油醚(epoxy bisphenol A diglycidyl ether,BADGE)是一些食品接触材料中聚合物的单体,主要用于食品罐头等容器的涂层中,也可用于有机溶胶类容器的涂层.BADGE可从涂层中迁移,并发生水解等化学反应生成以BADGE∙2...环氧树脂单体双酚A二缩水甘油醚(epoxy bisphenol A diglycidyl ether,BADGE)是一些食品接触材料中聚合物的单体,主要用于食品罐头等容器的涂层中,也可用于有机溶胶类容器的涂层.BADGE可从涂层中迁移,并发生水解等化学反应生成以BADGE∙2H_(2)O、BADGE∙H_(2)O为主的几种衍生物BADGEs.目前,废水处理厂水体(水相和颗粒物)、室内空气、灰尘等环境介质中都发现了BADGEs的踪迹,尤其是牙齿密封胶中其浓度水平较高.此外,在实验室模式生物、海洋哺乳动物以及人体血液、尿液、脂肪中均能够检出BADGEs,表明其可被生物体吸收.相关毒性实验表明,与内分泌干扰物双酚A类似,BADGEs具有一定的内分泌干扰性、细胞毒性、生殖发育毒性等.人体对BDAGE暴露的情况可通过监测其尿液中BADGEs的浓度水平体来体现.从现有数据看,人体对BADGEs的暴露水平不高,每日有效摄入量低于欧洲食品安全局于2004年规定的每日最大摄入量10 mg∙(kg∙Bw∙d)^(−1),其暴露主要来源于罐装食品.BADGEs属于增塑剂,可能会通过胎盘屏障,考虑到其毒性特征,建议孕妇少食罐装和袋装食品,以减少相关暴露.此外,需进一步研究BADGEs生物毒性和相关作用机理.展开更多
Hepatitis B virus (HBV) is a common viral pathogen that causes a substantial health burden worldwide. Remarkable progress has been made in our understanding of the natural stages of chronic HBV infection. A dynamic ba...Hepatitis B virus (HBV) is a common viral pathogen that causes a substantial health burden worldwide. Remarkable progress has been made in our understanding of the natural stages of chronic HBV infection. A dynamic balance between viral replication and host immune response is pivotal to the pathogenesis of liver disease. Knowledge of the HBV genome organization and replication cycle can unravel HBV genotypes and molecular variants, which contribute to the heterogeneity in outcome of chronic HBV infection. Most HBV infections are spontaneously resolved in immunocompetent adults, whereas they become chronic in most neonates and infants at a great risk of developing complications such as cirrhosis and hepatocellular carcinoma (HCC). Those with chronic HBV infection may present in one of the four phases of infection: immune tolerance, immune clearance [hepatitis B eantigen (HBeAg)-positive chronic hepatitis B (CHB)], inactive carrier state, and reactivation (HBeAg-negative CHB). Understanding the dynamic nature of chronic HBV infection is crucial in the management of HBV carriers. Long-term monitoring and optimal timing of antiviral therapy for chronic HBV infection help to prevent progression of HBV-related liver disease to its later stage, particularly in patients with higher risk markers of HCC, such as serum DNA concentration, HBeAg status, serum aminotransferase, HBV genotypes, and pre-core or core mutants.展开更多
The morphology and toxicity of Pseudo-nitzschia strain PP0201-01, isolated near the estuary of Changjiang (Yangtze) River in Year 2002 and tentatively identified as Pseudo-nitzschia pungens, were studied. The strain w...The morphology and toxicity of Pseudo-nitzschia strain PP0201-01, isolated near the estuary of Changjiang (Yangtze) River in Year 2002 and tentatively identified as Pseudo-nitzschia pungens, were studied. The strain was identified morphologically as P. pungens using scanning electronic microscope (SEM). The ana- lytical results of LC-PDA (liquid chromatography with photodiode array detector), LC-MS (liquid chromatogra- phy with mass detector), and the toxicity data from mouse bioassay, showed that no domoic acid was produced by the strain. However, the mechanism of domoic acid production by Pseudo-nitzschia species is complicated. More works are needed to assess the toxic species and to evaluate the potential risk of amnesic shellfish poison- ing (ASP) in China.展开更多
We read with great interest the paper written by Shiet a/, reviewing the molecular characteristics and stages of chronic hepatitis B virus （HBV） infection. We think that some points in the definition of occult HBV i...We read with great interest the paper written by Shiet a/, reviewing the molecular characteristics and stages of chronic hepatitis B virus （HBV） infection. We think that some points in the definition of occult HBV infection （OBI） and their conclusion about the management of OBI may need further considerations.展开更多
Bovine Herpesvirus-1 (BoHV-1) is distributed worldwide and is a major pathogen in cattle, being the causal agent of a variety of clinical syndromes. The aim of this study was to isolate and to characterize (molecular ...Bovine Herpesvirus-1 (BoHV-1) is distributed worldwide and is a major pathogen in cattle, being the causal agent of a variety of clinical syndromes. The aim of this study was to isolate and to characterize (molecular and biological characterization) BoHV-1 from 29 immunosuppressed animals. It was possible to obtain 18 isolates, each from a different animal, such as from the respiratory and reproductive tracts. In some cases the cytopathic effect was visible 12 hours post-inoculation, and became characteristic after 36-48 hours. Biological characteristics were evaluated and compared with Iowa and Colorado-1 reference strains, and differences were found in plaque size, virus titer measured by TCID50 and PFU/mL, and one step virus curves. These results showed that some isolates had a highly virulent-like behavior in vitro, compared to the reference strains, with shorter eclipse periods, faster release of virus into the supernatants, and higher burst size and viral titer. There were no differences in glycoprotein expression of BoHV-1 isolates, measured by Western blot on monolayers. Moreover, using restriction endonucleases analysis, most of the viruses were confirmed as BoHV-1.1 and just one of them was confirmed as BoHV-1.2a subtype. These findings suggest that some wild-type BoHV-1 isolates could be useful as seeds to develop new monovalent vaccines.展开更多
The Manila clam Venerupis philippinarum is a good biomonitor/bioindicator to marine metal pollution and is frequently used in aquatic toxicology. Two dominant pedigrees (white and zebra) of clam are distributed in the...The Manila clam Venerupis philippinarum is a good biomonitor/bioindicator to marine metal pollution and is frequently used in aquatic toxicology. Two dominant pedigrees (white and zebra) of clam are distributed in the Bohai Sea; however, little attention has been paid to potential biological differences between these two pedigrees. In this study, we tested the sensitivity of both pedigrees to marine metal (cadmium and zinc) pollution biomonitoring and marine environmental toxicology. Results demonstrate significant biological differences in gills of white and zebra clams based on metabolic profiles and antioxidant enzyme activities. In addition, we found that hypotaurine, malonate and homarine were relatively high in white clam gills, while alanine, arginine, glutamate, succinate, 4-aminobutyrate, taurine and betaine were high in zebra clam gills. Zebra clam gills were also more sensitive to a mixture of Cd and Zn, as shown by antioxidant enzyme activities and metabolic profiles, but white clam gills could accumulate more Zn. Therefore, we suggest that the white pedigree can be used as a biomonitor to marine Zn pollution, whereas the zebra pedigree can be used for toxicology studies on Cd and Zn mixed pollution.展开更多
AIM:To compares the clinical features of patients infected with hepatitis E virus(HEV) with or without severe jaundice.In addition,the risk factors for HEV infection with severe jaundice were investigated.METHODS:We e...AIM:To compares the clinical features of patients infected with hepatitis E virus(HEV) with or without severe jaundice.In addition,the risk factors for HEV infection with severe jaundice were investigated.METHODS:We enrolled 235 patients with HEV into a cross-sectional study using multi-stage sampling to select the study group.Patients with possible acute hepatitis E showing elevated liver enzyme levels were screened for HEV infection using serologic and molecular tools.HEV infection was documented by HEV antibodies and by the detection of HEV-RNA in serum.We used χ2 analysis,Fisher's exact test,and Student's t test where appropriate in this study.Significant predictors in the univariate analysis were then included in a forward,stepwise multiple logistic regression model.RESULTS:No significant differences in symptoms,alanine aminotransferase,aspartate aminotransferase,al-kaline phosphatase,or hepatitis B virus surface antigen between the two groups were observed.HEV infected patients with severe jaundice had significantly lower peak serum levels of γ-glutamyl-transpeptidase(GGT)(median:170.31 U/L vs 237.96 U/L,P = 0.007),significantly lower ALB levels(33.84 g/L vs 36.89 g/L,P = 0.000),significantly lower acetylcholine esterase(CHE) levels(4500.93 U/L vs 5815.28 U/L,P = 0.000) and significantly higher total bile acid(TBA) levels(275.56 μmol/L vs 147.03 μmol/L,P = 0.000) than those without severe jaundice.The median of the lowest point time tended to be lower in patients with severe jaundice(81.64% vs 96.12%,P = 0.000).HEV infected patients with severe jaundice had a significantly higher viral load(median:134 vs 112,P = 0.025) than those without severe jaundice.HEV infected patients with severe jaundice showed a trend toward longer median hospital stay(38.17 d vs 18.36 d,P = 0.073).Multivariate logistic regression indicated that there were significant differences in age,sex,viral load,GGT,albumin,TBA,CHE,prothrombin index,alcohol overconsumption,and duration of admission between patients infected with acute hepatitis E with and without severe jaundice.CONCLUSION:Acute hepatitis E patients may naturally present with severe jaundice.展开更多
AIM： To explore the relation between B-cell-specific Moloney murine leukemia virus insertion site 1 （Bmi-1） expression and the clinicopathological features of gastric carcinoma （GC）.METHODS： Immunohistochemistry...AIM： To explore the relation between B-cell-specific Moloney murine leukemia virus insertion site 1 （Bmi-1） expression and the clinicopathological features of gastric carcinoma （GC）.METHODS： Immunohistochemistry was used to detect the expression of Bmi-1 and ki-67. Doublelabeling staining was used to display the distribution of Bcl-2^＋/ki-67 cells in 162 cases of GC and its matched normal mucosa and precancerous lesion.RESULTS： The positive rate of Bmi-1 expression in GC（52.5%） was significantly higher than that in normal gastric mucosa （21.6%, X^2 = 33.088, P 〈 0.05）. The Bmi-1 expression in GC was closely related with the Lauren＇s and Borrmann＇s classification and clinicalstage （X^2 = 4.400, 6.122 and 11.190, respectively, P〈 0.05）. The expression of ki-67 was related to the Borrmann＇s classification （X^2 = 13.380, P 〈 0.05）.Bcl-2 expression was correlated with the Lauren＇s classification （Z2 = 4.725, P 〈 0.05）, and the Bmi-1 expression both in GC （rk = 0.157, P 〈 0.05） and inintestinal metaplasia （rk = 0.270, P 〈 0.05）.CONCLUSION： Abnormal Bmi-1 expression in GCmay be involved in cell proliferation, apoptosis andcancerization. This marker can objectively indicate theclinicopathological characteristics of GC.展开更多
With the increasing occurrence of haze during the summer, the physicochemical characteristics and toxicity differences in PM2.5 in different seasons are of great concern. Hangzhou is located in an area that has a subt...With the increasing occurrence of haze during the summer, the physicochemical characteristics and toxicity differences in PM2.5 in different seasons are of great concern. Hangzhou is located in an area that has a subtropical monsoon climate where the humidity is very high during both the summer and winter. However, there are limited studies on the seasonal differences in PM2.5 in these weather conditions. In this test, PM2.5 samples were collected in the winter and summer, the morphology and chemical composition of PM2.5 were analyzed, the toxicity of PM2.5 to human bronchial cells BEAS-2B was compared, and the correlation between PM2.5 toxicity and the chemical compo- sition was discussed. The results showed that during both the winter and summer, the main compounds in the PM2.5 samples were water-soluble ions, particularly SO4^2-, NO3^-, and NH4^＋, followed by organic components, while heavy metals were present at lower levels. The higher the mass concentration of PM2.5, the greater its impact on cell viability and ROS levels. However, when the mass concentration of PM2.5 was similar, the water extraction from the summer samples showed a greater impact on BEAS-2B than that from the winter samples. The cytotoxicity of PM2.5 was closely associated with heavy metals and organic pollutants but less related to water-soluble ions.展开更多
We analyze a Markov cellular automaton that models the spread of viruses that often progress to a chronic condition, such as human immunodeficiency virus （HIV） or hep- atitis C virus （HCV）. We show that the comple...We analyze a Markov cellular automaton that models the spread of viruses that often progress to a chronic condition, such as human immunodeficiency virus （HIV） or hep- atitis C virus （HCV）. We show that the complex dynamical system produces a Markov process at the later stages, whose eigenvectors corresponding to the eigenvalue 1 have physical significance for the long-term prognosis of the virus. Moreover we show that drug treatment leads to chronic conditions that can be modeled by Markov shifts with more optimal eigenveetors.展开更多
基金Supported by Science and Technology Department of Qingdao Government 07-2-1-15-nsh
文摘Hepatitis B virus (HBV) is a common viral pathogen that causes a substantial health burden worldwide. Remarkable progress has been made in our understanding of the natural stages of chronic HBV infection. A dynamic balance between viral replication and host immune response is pivotal to the pathogenesis of liver disease. Knowledge of the HBV genome organization and replication cycle can unravel HBV genotypes and molecular variants, which contribute to the heterogeneity in outcome of chronic HBV infection. Most HBV infections are spontaneously resolved in immunocompetent adults, whereas they become chronic in most neonates and infants at a great risk of developing complications such as cirrhosis and hepatocellular carcinoma (HCC). Those with chronic HBV infection may present in one of the four phases of infection: immune tolerance, immune clearance [hepatitis B eantigen (HBeAg)-positive chronic hepatitis B (CHB)], inactive carrier state, and reactivation (HBeAg-negative CHB). Understanding the dynamic nature of chronic HBV infection is crucial in the management of HBV carriers. Long-term monitoring and optimal timing of antiviral therapy for chronic HBV infection help to prevent progression of HBV-related liver disease to its later stage, particularly in patients with higher risk markers of HCC, such as serum DNA concentration, HBeAg status, serum aminotransferase, HBV genotypes, and pre-core or core mutants.
基金Supported by the projects of Ministry of Science and Technology (No.2001CB409704 and No. 2001BA804A20), and the innovation project ofthe Institute of Oceanology, CAS (No. 200223107)
文摘The morphology and toxicity of Pseudo-nitzschia strain PP0201-01, isolated near the estuary of Changjiang (Yangtze) River in Year 2002 and tentatively identified as Pseudo-nitzschia pungens, were studied. The strain was identified morphologically as P. pungens using scanning electronic microscope (SEM). The ana- lytical results of LC-PDA (liquid chromatography with photodiode array detector), LC-MS (liquid chromatogra- phy with mass detector), and the toxicity data from mouse bioassay, showed that no domoic acid was produced by the strain. However, the mechanism of domoic acid production by Pseudo-nitzschia species is complicated. More works are needed to assess the toxic species and to evaluate the potential risk of amnesic shellfish poison- ing (ASP) in China.
文摘We read with great interest the paper written by Shiet a/, reviewing the molecular characteristics and stages of chronic hepatitis B virus （HBV） infection. We think that some points in the definition of occult HBV infection （OBI） and their conclusion about the management of OBI may need further considerations.
基金the División de Investigación Universidad Nacional de Colombia,grants No.20201007738 and 202010013254
文摘Bovine Herpesvirus-1 (BoHV-1) is distributed worldwide and is a major pathogen in cattle, being the causal agent of a variety of clinical syndromes. The aim of this study was to isolate and to characterize (molecular and biological characterization) BoHV-1 from 29 immunosuppressed animals. It was possible to obtain 18 isolates, each from a different animal, such as from the respiratory and reproductive tracts. In some cases the cytopathic effect was visible 12 hours post-inoculation, and became characteristic after 36-48 hours. Biological characteristics were evaluated and compared with Iowa and Colorado-1 reference strains, and differences were found in plaque size, virus titer measured by TCID50 and PFU/mL, and one step virus curves. These results showed that some isolates had a highly virulent-like behavior in vitro, compared to the reference strains, with shorter eclipse periods, faster release of virus into the supernatants, and higher burst size and viral titer. There were no differences in glycoprotein expression of BoHV-1 isolates, measured by Western blot on monolayers. Moreover, using restriction endonucleases analysis, most of the viruses were confirmed as BoHV-1.1 and just one of them was confirmed as BoHV-1.2a subtype. These findings suggest that some wild-type BoHV-1 isolates could be useful as seeds to develop new monovalent vaccines.
基金Supported by the National Natural Science Foundation of China (No.41106102)Shandong Science Foundation of China (No. ZR2009CZ008)the 100 Talents Program of the Chinese Academy of Sciences
文摘The Manila clam Venerupis philippinarum is a good biomonitor/bioindicator to marine metal pollution and is frequently used in aquatic toxicology. Two dominant pedigrees (white and zebra) of clam are distributed in the Bohai Sea; however, little attention has been paid to potential biological differences between these two pedigrees. In this study, we tested the sensitivity of both pedigrees to marine metal (cadmium and zinc) pollution biomonitoring and marine environmental toxicology. Results demonstrate significant biological differences in gills of white and zebra clams based on metabolic profiles and antioxidant enzyme activities. In addition, we found that hypotaurine, malonate and homarine were relatively high in white clam gills, while alanine, arginine, glutamate, succinate, 4-aminobutyrate, taurine and betaine were high in zebra clam gills. Zebra clam gills were also more sensitive to a mixture of Cd and Zn, as shown by antioxidant enzyme activities and metabolic profiles, but white clam gills could accumulate more Zn. Therefore, we suggest that the white pedigree can be used as a biomonitor to marine Zn pollution, whereas the zebra pedigree can be used for toxicology studies on Cd and Zn mixed pollution.
基金Supported by Basic and Clinical Research of Capital Medical University,No. 2010JL10,to Xu B
文摘AIM:To compares the clinical features of patients infected with hepatitis E virus(HEV) with or without severe jaundice.In addition,the risk factors for HEV infection with severe jaundice were investigated.METHODS:We enrolled 235 patients with HEV into a cross-sectional study using multi-stage sampling to select the study group.Patients with possible acute hepatitis E showing elevated liver enzyme levels were screened for HEV infection using serologic and molecular tools.HEV infection was documented by HEV antibodies and by the detection of HEV-RNA in serum.We used χ2 analysis,Fisher's exact test,and Student's t test where appropriate in this study.Significant predictors in the univariate analysis were then included in a forward,stepwise multiple logistic regression model.RESULTS:No significant differences in symptoms,alanine aminotransferase,aspartate aminotransferase,al-kaline phosphatase,or hepatitis B virus surface antigen between the two groups were observed.HEV infected patients with severe jaundice had significantly lower peak serum levels of γ-glutamyl-transpeptidase(GGT)(median:170.31 U/L vs 237.96 U/L,P = 0.007),significantly lower ALB levels(33.84 g/L vs 36.89 g/L,P = 0.000),significantly lower acetylcholine esterase(CHE) levels(4500.93 U/L vs 5815.28 U/L,P = 0.000) and significantly higher total bile acid(TBA) levels(275.56 μmol/L vs 147.03 μmol/L,P = 0.000) than those without severe jaundice.The median of the lowest point time tended to be lower in patients with severe jaundice(81.64% vs 96.12%,P = 0.000).HEV infected patients with severe jaundice had a significantly higher viral load(median:134 vs 112,P = 0.025) than those without severe jaundice.HEV infected patients with severe jaundice showed a trend toward longer median hospital stay(38.17 d vs 18.36 d,P = 0.073).Multivariate logistic regression indicated that there were significant differences in age,sex,viral load,GGT,albumin,TBA,CHE,prothrombin index,alcohol overconsumption,and duration of admission between patients infected with acute hepatitis E with and without severe jaundice.CONCLUSION:Acute hepatitis E patients may naturally present with severe jaundice.
基金Supported by A special fund for Key University Laboratories from Department of Education of Liaoning Province, No. 2008S233
文摘AIM： To explore the relation between B-cell-specific Moloney murine leukemia virus insertion site 1 （Bmi-1） expression and the clinicopathological features of gastric carcinoma （GC）.METHODS： Immunohistochemistry was used to detect the expression of Bmi-1 and ki-67. Doublelabeling staining was used to display the distribution of Bcl-2^＋/ki-67 cells in 162 cases of GC and its matched normal mucosa and precancerous lesion.RESULTS： The positive rate of Bmi-1 expression in GC（52.5%） was significantly higher than that in normal gastric mucosa （21.6%, X^2 = 33.088, P 〈 0.05）. The Bmi-1 expression in GC was closely related with the Lauren＇s and Borrmann＇s classification and clinicalstage （X^2 = 4.400, 6.122 and 11.190, respectively, P〈 0.05）. The expression of ki-67 was related to the Borrmann＇s classification （X^2 = 13.380, P 〈 0.05）.Bcl-2 expression was correlated with the Lauren＇s classification （Z2 = 4.725, P 〈 0.05）, and the Bmi-1 expression both in GC （rk = 0.157, P 〈 0.05） and inintestinal metaplasia （rk = 0.270, P 〈 0.05）.CONCLUSION： Abnormal Bmi-1 expression in GCmay be involved in cell proliferation, apoptosis andcancerization. This marker can objectively indicate theclinicopathological characteristics of GC.
基金Project supported by the National Natural Science Foundation of China(No.41371447)the National Key Technologies R&D Program of China(No.2013BAC16B04)
文摘With the increasing occurrence of haze during the summer, the physicochemical characteristics and toxicity differences in PM2.5 in different seasons are of great concern. Hangzhou is located in an area that has a subtropical monsoon climate where the humidity is very high during both the summer and winter. However, there are limited studies on the seasonal differences in PM2.5 in these weather conditions. In this test, PM2.5 samples were collected in the winter and summer, the morphology and chemical composition of PM2.5 were analyzed, the toxicity of PM2.5 to human bronchial cells BEAS-2B was compared, and the correlation between PM2.5 toxicity and the chemical compo- sition was discussed. The results showed that during both the winter and summer, the main compounds in the PM2.5 samples were water-soluble ions, particularly SO4^2-, NO3^-, and NH4^＋, followed by organic components, while heavy metals were present at lower levels. The higher the mass concentration of PM2.5, the greater its impact on cell viability and ROS levels. However, when the mass concentration of PM2.5 was similar, the water extraction from the summer samples showed a greater impact on BEAS-2B than that from the winter samples. The cytotoxicity of PM2.5 was closely associated with heavy metals and organic pollutants but less related to water-soluble ions.
文摘We analyze a Markov cellular automaton that models the spread of viruses that often progress to a chronic condition, such as human immunodeficiency virus （HIV） or hep- atitis C virus （HCV）. We show that the complex dynamical system produces a Markov process at the later stages, whose eigenvectors corresponding to the eigenvalue 1 have physical significance for the long-term prognosis of the virus. Moreover we show that drug treatment leads to chronic conditions that can be modeled by Markov shifts with more optimal eigenveetors.
