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1.
Huan Jing Ke Xue ; 41(1): 262-272, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854927

RESUMO

Water is an important pathway for human exposure to heavy metals. Accurate assessment of the health risks that are related to exposure to heavy metals in drinking and household water are required for the preparation of targeted health risk prevention measures. This study explores and identifies the health risks related to exposure to heavy metals via drinking and household water pathways in Xigu District, Lanzhou, northwestern China, using household water samples and survey data obtained during July-September 2015 (wet season) and December 2015-January 2016 (dry season). During each period, drinking water and household water that were available for use by children aged 0-5 and 6-17 years were sampled and a questionnaire on water-related behavior patterns was completed for each household. Cd, Cr, Pb, and As concentrations were analyzed in all water samples, and were used along with water-related exposure factors from the questionnaires to estimate exposure doses and associated health risks using models recommended by the United States Environmental Protection Agency (US EPA). The results showed that the concentrations of Cd, Cr, Pb, and As in both drinking and household water samples did not exceed the relative thresholds defined in China's national water quality standards. The concentrations of heavy metals in household water were more affected by seasonal factors than of those of drinking water. The non-cancer and cancer risks were in the ranges of 2.82×10-8-2.43×10-2 and 7.55×10-9-3.62×10-5, respectively, which are within acceptable levels, although the non-cancer and cancer risks from drinking water were both higher than of those determined for household water. Furthermore, the non-cancer and cancer risks from household water for children aged 0-5 years were lower than of those for children aged 6-17 years in each period. However, the cancer risk from drinking water for children aged 0-5 years was lower than of that for children aged 6-17 years, whereas the reverse was found for non-cancer risks. This study indicates that Cd, Cr, Pb, and As in drinking and household water did not pose significant detrimental effects to human health, and that the refined exposure assessment used could reduce uncertainties in health risk assessments.


Assuntos
Água Potável/química , Monitoramento Ambiental , Metais Pesados/análise , Poluentes Químicos da Água/análise , Adolescente , Criança , Pré-Escolar , China , Humanos , Lactente , Recém-Nascido , Medição de Risco , Estações do Ano
2.
Huan Jing Ke Xue ; 40(12): 5191-5201, 2019 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854589

RESUMO

This paper discusses the concentration characteristics of PM2.5, as well as its relationship with meteorological factors in autumn and winter (from September to the following February), from 2013 to 2018 in the Beijing-Tianjin-Hebei (BTH) region. The accuracy and uncertainty of the air quality forecast models NAQPMS(nested air quality prediction modeling system), CMAQ(community multiscale air quality modeling system), and CAMx (comprehensive air quality model with extensions) were analyzed based on the model-predicted and measured PM2.5 concentration in autumn and winter from 2015 to 2018. The accuracy of NAQPMS, CMAQ, and CAMx during typical heavy air pollution was also tested. Moreover, methods to improve the accuracy of the model forecast were discussed. The results showed that the mean concentrations of PM2.5 in the BTH region were 122, 98, 82, 99, and 65 µg·m-3 in the five autumn and winter periods, respectively. When the air quality index (AQI) exceeded 150 during each autumn and winter, it reached 229, 198, 210, 204, and 180 µg·m-3, respectively. There were 64 occurrences of heavy regional PM2.5 air pollution in autumn and winter from 2013 to 2018. The average duration was longest in the 2013 to 2014 period, and shortest in the 2017 to 2018 period. The peak concentration and average concentration of PM2.5 decreased year on year, except for the period from 2016 to 2017. In autumn and winter, PM2.5 concentration had a relatively close relationship with relative humidity, wind and sunshine duration, compared with a weak relationship with temperature and air pressure. Regional heavy air pollution always happened under the condition of low wind speed(less than 2 m·s-1),higher relative humidity(greater than 65%),and southwest and northeast wind direction. In addition, the heavy air pollution of PM2.5 in BTH in autumn and winter can be effectively forecasted by NAQPMS, CMAQ, and CAMx. The predicted and measured PM2.5 concentration showed a close relationship. The models performed well in forecasting Zhangjiakou, Chengde, and Qinhuangdao, but by contrast overestimated in Tangshan, Shijiazhuang, Baoding, Beijing, and Tianjin. The uncertainty of emission sources, measured and predicted meteorological data, and the atmospheric chemical reaction mechanism may be the main reasons for the overestimate.

3.
Huan Jing Ke Xue ; 40(10): 4345-4354, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854801

RESUMO

Atmospheric particulate matter was collected during the heating period and the non-heating period of a typical steel industrial process in Northeast China to study the following:① the size-depended distribution and enrichment characteristics of polycyclic aromatic hydrocarbons (PAHs); ② the deposition concentrations of PAHs of different particle sizes in various organs of the human respiratory system; and 3 the risk from human respiratory exposure. The 14 priority PAHs in the samples were determined by high-performance liquid chromatography (HPLC), and respiratory exposure assessment was conducted by combining the atmospheric particle size fractionation sampling technique with an internal deposition model. The results showed that the PAH concentrations during the heating periods (743.9 ng·m-3) were higher than those during the non-heating periods (169.0 ng·m-3). Most PAH contributions (86.3%-89.9%) were related to fine particles with a diameter ≤ 2.06 µm; medium and low molecular weight PAHs showed two concentration peaks in 1.07-2.06 µm and 7.04-9.99 µm range, respectively. In contrast, high molecular weight PAHs showed a unimodal peak in 1.07-2.06 µm range. Four-ring PAHs accounted for 40% of the total PAHs concentrations. With respect to human exposure, 53.3% and 55.3% of the granular PAHs were deposited in the lungs during the heating and non-heating periods, respectively. The incremental lifetime cancer risk (R) of particulate PAHs in the population was calculated using the concentration in the human respiratory system and the total concentration associated with the particulate matter. The R values for adults ranged between 1.3×10-5 and 2.9×10-5 during the heating period, and between 3.1×10-6 and 6.0×10-6 during the non-heating period. The R values for children during the heating period ranged between 1.0×10-5 and 2.3×10-5, and between 2.4×10-6 and 4.8×10-6 during the non-heating period. The results indicated that particle size greatly affected the concentrations of particles deposited in the respiratory system and the level of carcinogenic risk. The combination of the grading sampling technique and the respiratory system settlement model can effectively avoid the over-evaluation of human respiratory exposure.

4.
Environ Geochem Health ; 40(1): 295-301, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27995354

RESUMO

A total of 60 children (31 males and 29 females) between the ages of 3 and 12 years were randomly selected from Lanzhou City in Gansu Province, northwest China. Hand (soil/dust) SD samples from these children were collected using hand wipes. We determined the approximate amounts of hand SD and the concentrations of three tracer soil elements (Ce, Y, and V) in these samples. The approximate amounts of hand SD ranged from 42.28 to 173.76 mg, with a median value of 85.42 mg. In addition, the mean amounts of hand SD estimated using the concentrations of Ce, Y, and V in the samples were 4.63, 3.43, and 3.42 mg, respectively. The amount of hand SD varied greatly among the age groups: primary school children had more hand SD than kindergarten children, males had more hand SD than females, and children from rural areas had more hand SD than those from urban areas. The rates of daily ingestion of hand SD for kindergarten and primary school children were estimated to be 7.73 and 6.61 mg/day, respectively.


Assuntos
Cério/análise , Poeira , Ingestão de Alimentos , Mãos , Boca , Solo , Vanádio/análise , Ítrio/análise , Criança , Pré-Escolar , China , Poeira/análise , Feminino , Humanos , Masculino , Espectrometria de Massas/métodos , Fatores Sexuais , Solo/química
5.
PLoS One ; 12(3): e0172337, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28264061

RESUMO

This study synthesized the wheat straw biochar-supported nanoscale zerovalent iron (BC-nZVI) via in-situ reduction with NaBH4 and biochar pyrolyzed at 600°C. Wheat straw biochar, as a carrier, significantly enhanced the removal of trichloroethylene (TCE) by nZVI. The pseudo-first-order rate constant of TCE removal by BC-nZVI (1.079 h-1) within 260 min was 1.4 times higher and 539.5 times higher than that of biochar and nZVI, respectively. TCE was 79% dechlorinated by BC-nZVI within 15 h, but only 11% dechlorinated by unsupported nZVI, and no TCE dechlorination occurred with unmodified biochar. Weakly acidic solution (pH 5.7-6.8) significantly enhanced the dechlorination of TCE. Chloride enhanced the removal of TCE, while SO42-, HCO3- and NO3- all inhibited it. Humic acid (HA) inhibited BC-nZVI reactivity, but the inhibition decreased slightly as the concentration of HA increased from 40 mg∙L-1 to 80 mg∙L-1, which was due to the electron shutting by HA aggregates. Results suggest that BC-nZVI was promising for remediation of TCE contaminated groundwater.


Assuntos
Carvão Vegetal , Água Subterrânea , Ferro , Tricloroetileno , Triticum , Poluentes Químicos da Água , Adsorção , Ânions/química , Carvão Vegetal/química , Água Subterrânea/química , Concentração de Íons de Hidrogênio , Cinética , Triticum/química
6.
Sci Rep ; 6: 18900, 2016 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-26742493

RESUMO

Epidemiological studies have revealed the association between tooth loss and the risk of esophageal cancer (EC); however, consistent results were not obtained from different single studies. Therefore, we conducted the present meta-analysis to evaluate the association between tooth loss and EC. We conducted electronic searches of PubMed until to February 10, 2015 to identify relevant observational studies that examined the association between tooth loss and the risk of EC. Study selection and data extraction from eligible studies were independently performed by two authors. The meta-analysis was conducted using Stata 12.0 software. Finally eight eligible publications with ten studies involving 3 cohort studies, 5 case-control studies, and 1 cross-sectional study were yielded. Meta-analysis identified tooth loss increased risk of EC 1.30 times (Relative risk = 1.30, 95% confidence interval = 1.06-1.60, I(2) = 13.5%). Dose-response analysis showed linear relationship between tooth loss and risk of EC (RR = 1.01, 95%CI = 1.00-1.03; P for non-linearity test was 0.45). Subgroup analysis proved similar results and publication bias was not detected. In conclusion, tooth loss could be considered to be a significant and dependent risk factor for EC based on the current evidence.


Assuntos
Neoplasias Esofágicas/diagnóstico , Perda de Dente/diagnóstico , Estudos de Casos e Controles , Estudos de Coortes , Estudos Transversais , Neoplasias Esofágicas/complicações , Neoplasias Esofágicas/patologia , Humanos , Prognóstico , Medição de Risco , Fatores de Risco , Perda de Dente/complicações , Perda de Dente/patologia
7.
J Hazard Mater ; 306: 278-285, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26774982

RESUMO

The demethylation potential of pollutants is arguably an innate component of their toxicity in environmental samples. A method was developed for determining the total demethylation potential of food samples (TDQ). The demethylation epigenetic toxicity was determined using the Hep G2 cell line transfected with pEGFP-C3 plasmids containing a methylated promoter of the EGFP reporter gene. The total demethylation potential of the sample extracts (the 5-AZA-CdR demethylation toxic equivalency) can be quantified within one week by using a standard curve of the 5-AZA-CdR demethylation agent. To explore the applicability of TDQ for environmental samples, 17 groundwater samples were collected from heavy polluted Kuihe river and the total demethylation potentials of the sample extracts were measured successfully. Meaningful demethylation toxic equivalencies ranging from 0.00050 to 0.01747µM were found in all groundwater sample extracts. Among 19 kinds of inorganic substance, As and Cd played important roles for individual contribution to the total demethylation epigenetic toxicity. The TDQ assay is reliable and fast for quantifying the DNA demethylation potential of environmental sample extracts, which may improve epigenetic toxicity evaluations for human risk assessment, and the consistent consuming of groundwater alongside the Kuihe river pose unexpected epigenetic health risk to the local residents.


Assuntos
Metilação de DNA , Água Potável/análise , Proteínas de Fluorescência Verde/genética , Água Subterrânea/análise , Poluentes Químicos da Água/análise , Arsênico/análise , Genes Reporter , Células Hep G2 , Humanos , Metais/análise
8.
Medicine (Baltimore) ; 94(38): e1640, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26402838

RESUMO

Association between coffee consumption and gastric cancer risk remains controversial. Hence, we performed a meta-analysis to investigate and quantify the potential dose-response association between long-term coffee consumption and risk of gastric cancer.Pertinent studies were identified by searching PubMed and Embase from January 1996 through February 10, 2015 and by reviewing the reference lists of retrieved publications. Prospective cohort studies in which authors reported effect sizes and corresponding 95% confidence intervals (CIs) of gastric cancer for 3 or more categories of coffee consumption were eligible. Results from eligible studies were aggregated using a random effect model. All analyses were carried out using the STATA 12.0 software.Nine studies involving 15 independent prospective cohorts were finally included. A total of 2019 incident cases of gastric cancer were ascertained among 1,289,314 participants with mean follow-up periods ranging from 8 to 18 years. No nonlinear relationship of coffee consumption with gastric cancer risk was indentified (P for nonlinearity = 0.53; P for heterogeneity = 0.004). The linear regression model showed that the combined relative risk (RR) of every 3 cups/day increment of total coffee consumption was 1.07 (95% CI = 0.95-1.21). Compared with the lowest category of coffee consumption, the RR of gastric cancer was 1.18 (95% CI = 0.90-1.55) for the highest (median 6.5 cups/day) category, 1.06 (95% CI = 0.85-1.32) for the second highest category (median 3.5 cups/day), and 0.97 (95% CI = 0.79-1.20) for the third highest category (median 1.5 cups/day). Subgroup analysis showed an elevated risk in the US population (RR = 1.36, 95% CI = 1.06-1.75) and no adjustment for smoking (RR = 1.67, 95% CI = 1.08-2.59) for 6.5 cups/day.Current evidence indicated there was no nonlinear association between coffee consumption and gastric cancer risk. However, high coffee consumption (more than 6.5 cups/day) might increase the risk of gastric cancer in the US population. More high quality studies were warranted to further investigate the association.


Assuntos
Café/efeitos adversos , Neoplasias Gástricas/induzido quimicamente , Relação Dose-Resposta a Droga , Humanos , Estudos Prospectivos
9.
Huan Jing Ke Xue ; 35(4): 1238-44, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-24946570

RESUMO

To investigate the sources and health risk of heavy metals in ambient air PM10 from the coking plant, the PM10 in the air around one coking plant was collected in June 2012. Then the heavy metals concentrations in PM10 were tested by the microwave-ICP-MS method. Furthermore, the USEPA's human exposure assessment model was applied to preliminarily evaluate the human health risks of the heavy metals in air particulate matter. The results show that the concentrations of 10 kinds of heavy metals in PM10 from the coking plant vary significantly, ranging from 3.06 x 10(-5) mg x m(-3) to 1.77 x 10(-2) mg x m(-3), of which the concentration of Cr is the highest, while the concentration of Co is the lowest, and the concentration of the carcinogenic substances is higher than that of the non-carcinogenic substances. The coking plant is identified to be the major source of the heavy metals in ambient air PM10, and Ni is the main polluting heavy metal. Moreover, the heavy risk assessment results reveal that the carcinogenic risks for adults are higher than children, while the carcinogenic risks in industrial areas and school relatively large. The non-carcinogenic risks for children are the highest in all the population, and the non-carcinogenic risks in residential area can not be ignored. Among the carcinogenic substances, the potential carcinogenic risks of Cd, Cr and As are comparatively large, Ni and Co have certain potential risks. Whereas, among the non-carcinogenic substances, the non-carcinogenic risks of Mn is great. Consequently, relevant departments should pay close attention to this situation.


Assuntos
Poluentes Atmosféricos/análise , Coque , Metais Pesados/análise , Material Particulado/análise , Adulto , Criança , Humanos , Indústrias , Medição de Risco
10.
J Microbiol Immunol Infect ; 47(1): 57-62, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23352331

RESUMO

BACKGROUND: The fimbriae of Salmonella enterica serovar Enteritidis are used for colonization and invasion into host cells, and have drawn considerable interest because fimbriae can serve as potential immunogens against many pathogenic bacteria that colonize on epithelial surfaces. The purpose of the study is to use a molecular adjuvant, C3d, to enhance the immunogenicity of FimA proteins against Salmonella enterica serovar Enteritidis. METHODS: FimA of type I fimbriae from Salmonella enteritidis and FimA with one copy of mC3d, two copies of mC3d2 and three copies of mC3d3 were cloned into the expression vector pCold-TF. Soluble fusion proteins of FimA with different copy of mC3d were induced by IPTG and expressed into Escherichia coli BL21 (DE3). Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed that the recombinant proteins from pCold-TF-fimA, TF-fimA-mC3d, TF-fimA-mC3d2, TF-fimA-mC3d3 were 70 kDa, 100 kDa, 130 kDa and 160 kDa, respectively. The fusion protein was recognized by rabbit anti-fimbriae polyclonal antibodies, and then visualized by goat anti-rabbit polyclonal antibodies with a chrome appearance by enzyme-subtract interaction. The recombinant proteins were purified by Ni-TED (tris-carboxymethyl ethylene diamine), immobilized metal ion affinity chromatography (IMAC). Balb/c mice were subcutaneously immunized with the purified proteins and the immune response was monitored by an enzyme-linked immunosorbent assay (ELISA) for FimA-specific antibody. The immunized mice were challenged with a 10-fold LD50 dose (i.e., 100 CFU) of Salmonella enterica serovar Enteritidis standard strain (SD-2) 1 week after the second immunization. RESULTS: The immunized mice with the fusion proteins FimA-mC3d2 and FimA-mC3d3 had increased levels of ELISA titer of antibody that were 2 and 4 logs, respectively, more immunogenic than the TF-FimA protein alone. The challenge results showed that immune protection rate in the mice immunized with 10 µg of FimA, FimA-mC3d2, and FimA-mC3d3 were 50%, 75% and 100%, respectively. CONCLUSION: We conclude that mC3d can be expressed in a prokaryotic vector and enhance the immune response of the recombinant protein. FimA-mC3d3 is potentially a subunit vaccine against S. enterica serovar Enteritidis infection.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Antígenos de Bactérias/imunologia , Complemento C3d/administração & dosagem , Proteínas de Fímbrias/imunologia , Salmonelose Animal/prevenção & controle , Vacinas contra Salmonella/imunologia , Salmonella enteritidis/imunologia , Vacinação/métodos , Adjuvantes Imunológicos/genética , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/genética , Complemento C3d/genética , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Proteínas de Fímbrias/genética , Injeções Subcutâneas , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Salmonelose Animal/imunologia , Vacinas contra Salmonella/administração & dosagem , Vacinas contra Salmonella/genética , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
11.
Exp Ther Med ; 4(5): 938-948, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23226753

RESUMO

The aim of this study was to explore the cytochrome P450 2E1 (CYP2E1) RsaI/PstI polymorphism and risk of esophageal cancer (EC) in mainland Chinese populations. A systematic search of PubMed, EMBASE, Web of Science, CBM, CNKI and VIP databases for publications on the CYP2E1 RsaI/PstI polymorphism and risk of EC was performed. and the genotype data were analyzed in a meta-analysis. Odds ratios (ORs) with relevant 95% confidence intervals (CIs) were estimated to assess the association. Sensitivity analysis, test of heterogeneity and assessment of publication bias were performed. The search yielded 17 studies including 18 trails involving 1,663 cases and 2,603 controls. The meta-analyses showed a significant association between the CYP2E1 RsaI/PstI polymorphism and risk of EC in the mainland Chinese population (c2 vs. c1: OR=0.64; 95% CI, 0.50-0.81; P<0.001; c2/c2 vs. c1/c1: OR=0.73; 95% CI, 0.57-0.93; c2/c2 vs. c1/c1+c1/c2: OR=0.76; 95% CI, 0.60-0.96; P=0.02; c1/c2 vs. c1/c1: OR=0.54; 95% CI, 0.38-0.75; P<0.001; c1/c2+c2/c2 vs. c1/c1: OR=0.48; 95% CI, 0.34-0.70; P<0.001). An increased cancer risk in all genetic models was identified following stratification by ethnicity, source of controls and tumor type. In conclusion, in all genetic models, the association between the CYP2E1 RsaI/PstI polymorphism and risk of EC in the mainland Chinese population was significant. This meta-analysis suggests that the CYP2E1 RsaI/PstI polymorphism is a risk factor for EC, and the c2 allele is a factor that lowers the possibility of EC in the mainland Chinese population and this association did not change due to ethnic differences in genetic backgrounds and the environment.

12.
Asian Pac J Cancer Prev ; 13(7): 3123-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22994721

RESUMO

OBJECTIVE: Experimental studies have suggested green tea to be a chemopreventive agent for colorectal cancer, and many studies have examined possible associations. However, the conclusions were inconsistent or even contradictory, so we performed a meta-analysis based on published case-control studies to explore if green tea is indeed a protective factor. METHODS: PubMed was searched up to May 10th, 2012 for relevant studies, and references of included studies were manually searched. Finally 13 eligible studies, involving 12,636 cases and 38,419 controls were identified. After data extraction, a meta-analysis was performed using CMA v2 software. RESULTS: The results indicated there may be a weak but not statistically significant reduced risk of colorectal cancer with high dose of green tea intake (OR=0.95, 95% CI:0.81-1.11, p=0.490.69-0.98). This protective effect was also found in all subgroups, except in American and European populations. Sensitivity analysis indicated the result to be robust. Publication bias was not detected by either funnel plot or Egger tests. CONCLUSION: The results of this meta-analysis indicate a weak lower tendency for colorectal cancer development with green tea consumption, but available epidemiologic data are insufficient to conclude that green tea may protect against colorectal cancer in humans.


Assuntos
Camellia sinensis/química , Neoplasias Colorretais/epidemiologia , Extratos Vegetais/administração & dosagem , Chá , Bebidas , Estudos de Casos e Controles , Neoplasias Colorretais/prevenção & controle , Humanos , Risco
13.
Asian Pac J Cancer Prev ; 13(7): 3299-303, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22994751

RESUMO

OBJECTIVE: To investigate the association between xeroderma pigmentosum group D (XPD) Asp312Asn polymorphism and esophageal cancer (EC) susceptibility by meta-analysis. METHODS: We searched PubMed up to April 9th, 2012, to identify relevant papers, and 8 published case-control studies including 2165 EC patients and 3141 healthy controls were yielded. Odds ratios (ORs) with relevant 95% confidence intervals (CIs) were applied to assess the association between XPD Asp312Asn polymorphism and EC susceptibility with the Comprehensive Meta-Analysis software, version 2.2. RESULTS: Overall, the meta-analysis results suggested the XPD Asp312Asn polymorphism to be significantly associated with EC susceptibility [(Asn/Asn+Asp/Asn) vs. Asp/Asp: OR=1.20, 95%CI=1.05-1.36, p=0.01; and Asp/Asn vs. Asp/Asp: OR=1.15, 95%CI=1.01-1.31, p=0.04]. In the subgroup analysis by ethnicity and cancer type, significantly associations were found for Caucasian populations [(Asn/Asn+Asp/Asn) vs. Asp/Asp: OR=1.26, 95%CI=1.08-1.47, p<0.001; Asp/Asn vs. Asp/Asp: OR=1.19, 95%CI=1.02- 1.40, p=0.03] and esophageal squamous cell carcinoma [(Asn/Asn+Asp/Asn) vs. Asp/Asp: OR=1.19, 95%CI=1.01-1.41, p=0.04]. There was no heterogeneity and no publication bias existed. CONCLUSIONS: This meta-analysis shows that the XPD Asp312Asn polymorphism may be a risk factor for developing EC, especially for Caucasian populations and esophageal squamous cell carcinoma.


Assuntos
Neoplasias Esofágicas/genética , Proteína Grupo D do Xeroderma Pigmentoso/genética , Carcinoma de Células Escamosas/genética , Estudos de Casos e Controles , Grupo com Ancestrais do Continente Europeu/genética , Predisposição Genética para Doença , Genótipo , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único , Fatores de Risco
14.
Huan Jing Ke Xue ; 32(5): 1329-39, 2011 May.
Artigo em Chinês | MEDLINE | ID: mdl-21780587

RESUMO

This study was carried out in Biyang County, located in the junction of Yangtze river and Huaihe river. Drinking water samples of 20 sites in urban and rural areas in this county were collected to measure 14 heavy metals by ICP/MS. About 2 500 subjects with different age and sex were selected to measure exposure factors. Time-activity of drinking water by ingestion and dermal contact of each individual subject during the last three days were kept in dairy in detail by questionnaires. Intake of drinking water from direct and indirect consumption of water and time duration of dermal contact to water in each individual subject were kept in record based on real time measurements. Human health risks were assessed and sensitivity of exposure factors and uncertainty of risks were also analyzed. The results showed that the average drinking water intake rate of male and female are 2276 mL/d, 2265 mL/d in urban adults and 2464 mL/d, 2170 mL/d in rural adults respectively. Body surface area of male and female are 1.806 m2, 1.641 m2 in urban adults and 1.747 m2, 1.617 m2 in rural adults respectively. The contents of 14 heavy metals in this study area are all below the national drinking water standards. Cancer risks from exposure to As are ranged from 2.5 x 10(-6) to 5.2 x 10(-6) through ingestion and 1.1 x 10(-7) to 2.3 x 10(-7) through dermal exposure. Non-cancer risks are ranged from 2.1 x 10(-7) to 1.7 x 10(-6) through ingestion and 1.0 x 10(-8) to 6.0 x 10(-8) through dermal exposure. Non-cancer risks in rural population are 2.1 times to 5.6 times to the risks in urban populations. However all the risks are below the acceptable level. The sensitivity of various exposure factors including drinking water intake rate, dermal exposure time and body surface area are 71.5%. This indicates that exposure factors play a very important role in health risk assessment. Health risks in this research based on real measurement of exposure factors are about 0.94 time to 6.33 times higher than the risks based on the references of the data from the exposure factors handbooks in other countries. This study showed that the accuracy of health risk assessment could be improved a lot by the real measurements of exposure factors. Attentions should be attached to exposure factor investigation to decrease uncertainty of health risk assessment.


Assuntos
Exposição Ambiental/análise , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Adulto , Criança , Pré-Escolar , China , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental , Feminino , Humanos , Lactente , Masculino , Saúde Pública , Medição de Risco , Rios , Poluentes Químicos da Água/efeitos adversos , Adulto Jovem
15.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 25(3): 201-3, 2009 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-19257980

RESUMO

AIM: To investigate the effects of immunoglobulin G (IgG) on the expression of toll-like receptor 4 (TLR4) and secretion of cytokines in microglial cells in vitro. METHODS: Cultured primary rat microglial cells were stimulated with different concentrations of rat IgG (2 mg/L, 20 mg/L, 200 mg/L) and lipopolysaccharide (LPS) 10 mg/L for 24 h, respectively. The TLR4 expression in the microglial cells was examined by immunofluorescence staining and tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) levels in the culture medium were assayed by ELISA. RESULTS: IgG stimulation induced a significant TLR4 expression and TNF-alpha secretion in cultured microglial cells in a dose-dependent manner, while IFN-gamma was not detected in the same medium samples. As a positive control, LPS caused increases of TLR4 expression and both IFN-gamma and TNF-alpha production in the microglial cells. CONCLUSION: TLR4 expression could be induced in microglia in vitro by non-pathogenic protein, IgG from the same species. Therefore, congeneric IgG stimulation might lead to proinflammmatory cytokine production, probably via MyD88-dependent pathway. This finding suggests that TLR4 may play more roles than pathogen recognition of innate immune reactivity, at least in the central nervous system.


Assuntos
Citocinas/metabolismo , Imunoglobulina G/farmacologia , Microglia/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Animais , Animais Recém-Nascidos , Células Cultivadas , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Interferon gama/metabolismo , Microglia/citologia , Microglia/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
16.
J Neurosci Res ; 86(16): 3556-65, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18756515

RESUMO

Blood-brain barrier (BBB) opening occurs under many physiological and pathological conditions. BBB opening will lead to the leakage of large circulating molecules into the brain parenchyma. These invasive molecules will induce immune responses. Microglia and astrocytes are the two major cell types responsible for immune responses in the brain, and Fc gamma receptor I (FcgammaRI) and Toll-like receptor 4 (TLR4) are the two important receptors mediating these processes. Data suggest that activation of the FcgammaRI pathway mediates antiinflammatory processes, whereas activation of TLR4 pathway leads to proinflammatory activities. In the present study, we tested the hypothesis that BBB opening could lead to alterations in FcgammaRI and TLR4 pathways in microglia and astrocytes, thus limiting excessive inflammation in the brain. The transient BBB opening was induced by adrenaline injection through a caudal vein in Sprague-Dawley rats. We found that the FcgammaRI pathway was significantly activated in both microglia and astrocytes, as exhibited by the up-regulation of FcgammaRI and its key downstream molecule Syk, as well as the increased production of the effector cytokines, interleukin (IL)-10 and IL-4. Interestingly, after transient BBB opening, TLR4 expression was also increased. However, the expression of MyD88, the central adapter of the TLR4 pathway, was significantly inhibited, with decreased production of the effector cytokines IL-12a and IL-1beta. These results indicate that, after transient BBB opening, FcgammaRI-mediated antiinflammatory processes were activated, whereas TLR4-mediated proinflammatory activities were inhibited in microglia and astrocytes. This may represent an important neuroprotective mechanism of microglia and astrocytes that limits excessive inflammation after BBB opening.


Assuntos
Barreira Hematoencefálica/imunologia , Encefalite/imunologia , Gliose/imunologia , Neuroglia/imunologia , Receptores de IgG/imunologia , Receptor 4 Toll-Like/imunologia , Animais , Astrócitos/imunologia , Astrócitos/metabolismo , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/fisiopatologia , Citocinas/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/imunologia , Encefalite/metabolismo , Encefalite/fisiopatologia , Epinefrina/farmacologia , Gliose/metabolismo , Gliose/fisiopatologia , Tolerância Imunológica/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Microglia/imunologia , Microglia/metabolismo , Fator 88 de Diferenciação Mieloide/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , Neuroglia/citologia , Neuroglia/metabolismo , Proteínas Tirosina Quinases/imunologia , Proteínas Tirosina Quinases/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de IgG/metabolismo , Transdução de Sinais/imunologia , Quinase Syk , Receptor 4 Toll-Like/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/imunologia , Vasoconstritores/farmacologia
17.
Neurochem Res ; 33(9): 1901-10, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18357518

RESUMO

To clarify the response of leptomeningeal cells to immune stimulation, the effect of lipopolysaccharide (LPS) on expression of IL-6 receptors in the cultured leptomeningeal cells was investigated. The results showed that the expression of IL-6R alpha was invisible in the purified leptomeningeal cells while it was seen in the cells when they were co-cultured with astrocytes. On the other hand, GP130 was moderately expressed in both conditions. Following incubation with different doses of LPS, IL-6R alpha expression in purified leptomeningeal cells was increased in a time- and dose-dependent manner, while GP130 level remained unchanged. Concomitantly, phosphorylated ERK1/2 level was increased following LPS stimulation and its inhibition by PD98059 attenuated the LPS-induced increase of IL-6R alpha expression. These data indicate that leptomeningeal cells can respond to immunogenic stimuli as manifested by expression of cytokine receptors. Moreover, ERK1/2 pathway seems to be involved in the process of LPS-induced IL-6R alpha up-regulation in leptomeningeal cells.


Assuntos
Células Cultivadas/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Meninges/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Receptores de Interleucina-6/metabolismo , Animais , Animais Recém-Nascidos , Receptor gp130 de Citocina/metabolismo , Relação Dose-Resposta a Droga , Ativação Enzimática , Inibidores Enzimáticos/metabolismo , Flavonoides/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Meninges/citologia , Fosforilação , Ratos , Ratos Sprague-Dawley
18.
Histochem Cell Biol ; 128(6): 533-40, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17926059

RESUMO

It is well established that reciprocal modulation exists between the central nervous system and immune system. Interleukin (IL)-1beta, a proinflammatory cytokine secreted at early stage of immune challenge, has been recognized as one of the informational molecules in immune-to-brain communication. However, how this large molecule is transmitted to the brain is still unknown. In recent years it has been reported that the cranial nerves, especially the vagus, may play a pivotal role in this regard. It is proposed that IL-1beta may bind to its corresponding receptors located in the glomus cells of the vagal paraganglia and then elicit action potentials in the nerve. The existence of IL-1 receptor type I (IL-1RI) in the vagal paraganglia has been shown. The carotid body, which is the largest peripheral chemoreceptive organ, is also a paraganglion. We hypothesize that the carotid body might play a role similar to the vagal paraganglia because they are architectonically similar. Recently we verified the presence of IL-1RI in the rat carotid body and observed increase firing in the carotid sinus nerve following IL-1beta stimulation. The aim of this study was to observe the changes in expression of IL-1RI and tyrosine hydroxylase (TH), a rate-limiting enzyme for catecholamine synthesis, in the glomus cells of the rat carotid body following intraperitoneal injection of IL-1beta. The radioimmunoassay result showed that the blood IL-1beta level was increased after the intraperitoneal injection of rmIL-1beta (750 ng/kg) from 0.48+/-0.08 to 0.78+/-0.07 ng/ml (P<0.05). Immunofluorescence and Western blot analysis showed that the expression of IL-1RI and TH in the rat carotid body was increased significantly following peritoneal IL-1beta stimulation. In addition, double immunofluorescence labeling for TH and PGP9.5, a marker for glomus cells, or TH immunofluoresence with hematoxylin-eosin (HE) counterstaining revealed that a considerable number of glomus cells did not display TH immunoreactivity. These data provide morphological evidence for the response of the carotid body to proinflammatory cytokine stimulation. The results also indicate that not all of the glomus cells express detectable TH levels either in normal or in some abnormal conditions.


Assuntos
Corpo Carotídeo/fisiologia , Interleucina-1beta/farmacologia , Receptores de Interleucina-1/fisiologia , Tirosina 3-Mono-Oxigenase/metabolismo , Animais , Corpo Carotídeo/efeitos dos fármacos , Corpo Carotídeo/enzimologia , Injeções Intraperitoneais , Interleucina-1beta/administração & dosagem , Masculino , Ratos , Ratos Sprague-Dawley , Receptores de Interleucina-1/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/efeitos dos fármacos
19.
Curr Eye Res ; 32(3): 233-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17453943

RESUMO

PURPOSE: To investigate the involvement of the extracellular signal-regulated kinase (ERK) signaling pathway after intravitrevous injection of glutamate in rat retina. METHODS: Three groups of five Sprague-Dawley rats each were studied. Group I was a normal control group, intravitreal saline injections. In Group II, one eye received an intravitreal glutamate injection (375 nmol, dissolved in saline) while the contralateral eye served as control. In Group III, intravitreal PD98059 (100 micro mol, an inhibitor of ERK) injections were administered 1 hr before glutamate injections. Seven days after injections, phosphorylated (activated) ERK in retina was localized by immunohistochemistry and fluorescent double labeling of retinal cryosections. Specific ERK blockade was documented to assess the functional significance of activated ERK. TUNEL staining was performed to assess apoptotic cell death. RESULTS: Expression of phosphorylated ERK in rat retina was observed in the inner nuclear layer, the outer nuclear layer, and the nerve fiber layer after 3 days intravitreous injection of glutamate, increasing significantly after 7 days. Double immunofluorescence labling demonstrated that the increased retinal immunostaining for phospho-ERK was predominantly localized to the retinal Müller cells after 7 days intravitreous injection of glutamate. Moreover, blocking activation of ERK significantly improved the number of TUNEL-positive cells in the eyes receiving intravitreal PD98059 injections compared with the eyes receiving glutamate injections. CONCLUSIONS: The ERK pathway is involved in signal transduction in the retina after excessive stimulation by glutamate, which may contribute to the antiapoptotic role in retinal ganglion cell death induced by glutamate.


Assuntos
Apoptose/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Ácido Glutâmico/farmacologia , Células Ganglionares da Retina/patologia , Transdução de Sinais/fisiologia , Animais , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Flavonoides/farmacologia , Técnica Indireta de Fluorescência para Anticorpo , Técnicas Imunoenzimáticas , Marcação In Situ das Extremidades Cortadas , Injeções , Fosforilação , Ratos , Ratos Sprague-Dawley , Células Ganglionares da Retina/enzimologia , Corpo Vítreo
20.
Life Sci ; 79(20): 1895-905, 2006 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-16978658

RESUMO

The enhanced production of nitric oxide (NO) via inducible nitric oxide synthase (iNOS) has been implicated in the pathogenesis of neuronal apoptosis after acute traumatic spinal cord injury (SCI). In the present study, to further characterize the pathways mediating the synthesis and release of NO, we examined activation of extracellular signal regulated kinase 1/2 (ERK1/2) and p38 mitogen-activated protein kinases (p38 MAPK) in microglia/macrophages in the injured area of adult rats subjected to a complete transection at the T10 vertebrae level and assessed their role in NO production and survival of neurons by using immunohistochemistry, Western blot, RT-PCR and pharmacological interventions. Results showed activation of microglia/macrophages featured by morphological changes, as visualized immunohistochemically with the marker OX-42, in the areas adjacent to the lesion epicenter 1 h after surgery. Concomitantly, iNOS mRNA and its protein in the activated microglia/macrophages were also significantly upregulated at early hours after surgery. Their levels were maximal at 6 h, persisted for at least 24 h, and returned to basal level 72 h after SCI. Furthermore, phosphorylated ERK1/2 and p38 MAPK were activated as well in microglia/macrophages in injured area with a similar time course as iNOS. With administration of L-NAME, a NOS inhibitor, the number of apoptotic neurons was clearly decreased, as assessed with TUNEL method at 24 h after SCI. In parallel, loss of neurons induced by SCI, assessed with NeuN immunohistochemistry, was also diminished. Moreover, the effect of inhibition of phosphorylation ERK1/2 and p38 MAPK by corresponding inhibitors PD98059 and SB203580 administered before and after SCI was also investigated. Inhibition of p38 effectively reduced iNOS mRNA expression and rescued neurons from apoptosis and death in the area adjacent to the lesion epicenter; whereas the inhibition of ERK1/2 had a smaller effect on decrease of iNOS mRNA and no long-term protective effect on cell loss. These results indicate the ERK1/2 and p38 MAPK signaling pathway, especially the latter, play an important role in NO-mediated degeneration of neuron in the spinal cord following SCI. Strategies directed to blocking the initiation of this cascade prove to be beneficial for the treatment of acute SCI.


Assuntos
Ativação de Macrófagos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Degeneração Neural/enzimologia , Óxido Nítrico Sintase Tipo II/metabolismo , Traumatismos da Medula Espinal/enzimologia , Traumatismos da Medula Espinal/patologia , Animais , Macrófagos/enzimologia , Macrófagos/imunologia , Masculino , Microglia/imunologia , Proteína Quinase 1 Ativada por Mitógeno/análise , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/análise , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/análise , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Neurônios/enzimologia , Neurônios/patologia , Óxido Nítrico Sintase Tipo II/análise , Óxido Nítrico Sintase Tipo II/genética , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno/análise , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
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