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Objective To analyze the enzymatic activity of Leptospira interrogans ( L. interrogans) LA_2144 gene product to hydrolyze platelet activating factor acetylhydrolase ( PAF-AH) and phosphatidase A2(PLA2). Methods Bioinformatic softwares were used to predict transmembrane regions, signal peptides and domains of the LA_2144 gene of L. interrogans strain Lai. A prokaryotic expression system for signal peptide-free LA_2144 gene was established. The expressed target recombinant protein rLep2144 was extrac-ted by Ni-NTA affinity chromatography and then renatured. Spectrometry was used to detect the activity of rLep2144 to hydrolyze PAF-AH substrate 2-thio PAF and the Km and Kcat values as well as the activity to hy-drolyze PLA2 substrate arachidonoyl 2-thio PC. Real-time fluorescence quantitative RT-PCR and Western blot were performed to detect the transcription, protein expression and secretion of LA_2144 gene during infection of human and mouse vascular endothelial cells ( HUVEC and EOMA) with L. interrogans. Results L. interrogans LA_2144 gene contained a signal peptide and a domain belonging to SGNH hydrolase super-family, but no transmembrane regions. The established prokaryotic expression system for signal peptide-free LA_2144 gene could efficiently express rLep2144. The extracted rLep2144 was shown as a single protein fragment in separation gel and then successfully renatured. rLep2144 had a stronger PAF-AH activity with the Km and Kcat values of 688. 235 μmol/L and 0. 976/s, but its PLA2 activity was relatively weak. Expres-sion of the LA_2144 gene at mRNA and protein levels in HUVEC and EOMA was rapidly increased after the cells were infected with L. interrogans (P<0. 05) and the secretion of LA_2144 gene product could be detec-ted. Conclusions L. interrogans LA_2144 gene product had a stronger PAF-AH and a certain PLA2 activi-ty, which might involve in the hemorrhage and inflammatory response in leptospirosis.
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Objective: To explore correlation between plasma oxidized low density lipoprotein (ox-LDL) and endothelial injury degree in patients with coronary heart disease (CHD).Methods: A total of 80 CHD patients were enrolled as CHD group, and 21 healthy subjects were selected as healthy control group.Plasma ox-LDL, circulatory endothelial cell count (CEC), nitric oxide (NO) levels were measured and compared between two groups, and their correlation was analyzed.Results: Compared with healthy control group, there were significant rise in plasma ox-LDL level[(350±173) μg/L vs.(687±169) μg/L]and CEC[(2.5±0.5) ×106个/L vs.(9.0±1.7) ×106个/L], and significant reduction in NO level[(77.4±21.1) μmol/L vs.(52.3±16.6) μmol/L]in CHD group, P<0.05 or <0.01.Spearman correlation analysis indicated that ox-LDL was significant positively correlated with CEC (r=0.793, P=0.019), and ox-LDL, CEC were significant negatively correlated with NO level (r=-0.782,-0.952, P=0.013, 0.021).Conclusion:There are significant positively correlation between ox-LDL and circulatory endothelial cell count(Vascular endothelial injury degree) in CHD patients, therefore, its treatment should focus on anti-inflammatory and endothelial cell function protection.
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This study was aimed to investigate the influence on component content indexes,which included chlorogenic acid and luteolin of honeysuckle by the absorption of chemical insecticide thiamethoxam.High-performance liquid chromatography (HPLC) method was used in the analysis of content determination of component content indexes of honeysuckle samples by different concentrations of thiamethoxam.SPSS was used in the statistical analysis.The results showed that compared to samples from the blank control group,the content of chlorogenic acid had the increasing tendency in the honeysuckle groups with different concentrations of thiamethoxam.However,there was no significant difference among different experiment groups.There was no significant difference on luteolin among honeysuckle groups with different concentrations of thiamethoxam and the blank control group.It was concluded that at the recommended dose and high-powered dose of thiamethoxam,there was some influence on the content of chlorogenic acid.However,there was no significant effect on the content of luteoloside.And the quality scores of both contents were within the range defined in the Chinese Pharmacopoeia(2010 edition).
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<p><b>OBJECTIVE</b>The aim of this study was to investigate the impact of air pollution on the number of pediatric outpatient and emergency room visits in January 2013.</p><p><b>METHODS</b>Health-related data was from a major hospital in Haidian,Beijing while related data on air pollution was from the Chinese Research Academy of Environmental Sciences. Data on weather was from the China Weather Website. Number of hospital outpatient visits per day during the haze period was compared to those from the previous year to get the increase of percentage. Concentration-response functions were estimated using generalized additive modeling with natural log link function, while multiple structural change test was used to determine the changing point in CRFs. Constrained piecewise linear function was used to estimate the risks for different segments of CRFs.</p><p><b>RESULTS</b>The peak of NO(X), SO₂, PM(2.5) and PM(10) reached 672.63 µ g/m³, 146.20 µ g/m³, 312.19 µ g/m³ and 995.00 µ g/m³, around 28 December 2012 and 10 January 2013. The peaks of visits to the pediatric department were observed at the some days, showing 47.75% and 34.14% of increase in the visits to the pediatric department. In the low or intermediate ranges of concentration, all the four air pollutants were significantly associated with pediatric outpatient visits, in the form of C- and S- shape of concentration-response function. However, in the range of high concentration, only PM(10) and SO₂were significantly associated with the number of visits to the pediatric emergency room, appeared as the J-shape form. Discernable thresholds were found in S- and J- shapes which were located at 200 µg/m³, 20 µg/m³, 40 µg/m³ and 100 µ g/m³ for NO(X), SO₂, PM(2.5) and PM(10), respectively.</p><p><b>CONCLUSION</b>Air pollution during the haze period was associated with the increase of pediatric outpatient and emergency room visits. There were different sensitive groups within the pediatric cases. Their susceptibility showed a decreasing trend from C-, S-, to J- shape related group.</p>
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Child , Humans , Air Pollution , China , Epidemiology , Emergency Service, Hospital , Outpatients , WeatherABSTRACT
<p><b>OBJECTIVE</b>To construct a knockout fliY gene mutant strain of Campylobacter jejuni for determining the role of FliY protein in flagellar movement related to bacterial motility, chemotaxis and colonization.</p><p><b>METHODS</b>The plasmid pBluescript-II-SK was used to construct the suicide plasmid; according to homologous exchange principle, the suicide plasmid was utilized to generate fliY gene knockout mutant(fliY) in Campylobacter jejuni strain NCTC11168. The fliY mutant strain was identified by PCR, sequencing and Western blotting. The chemotactic and colonizing abilities of fliY mutant were determined by colony migration test and bacterial chemotactic test in vitro, and colonization test in jejunum of mice.</p><p><b>RESULTS</b>The fliY(-)mutant strain showed a growth curve in medium similar to that of wild-type strain. PCR, sequencing and Western blotting assay confirmed that the fliY gene in fliY(-)mutant was deleted. Compared to the wild-type strain, the colonies of fliY-mutant on semisolid plate were much smaller (P <0.05), the chemotactic ability of fliY mutant towards sodium deoxycholate and bovine bile was significantly attenuated (P <0.05), and the number of fliY mutant (CFU) in jejunal tissue specimens of the infected mice was significantly decreased (P<0.05).</p><p><b>CONCLUSION</b>The function of C.jejuni fliY gene refers to controlling flagellar movement, which is involved in bacterial chemotaxis and colonization.</p>
Subject(s)
Animals , Mice , Bacterial Proteins , Genetics , Campylobacter jejuni , Genetics , Virulence , Chemotaxis , Genetics , Gene Knockout Techniques , Jejunum , Microbiology , Membrane Proteins , Genetics , Mice, Inbred BALB CABSTRACT
Objective To investigate the function of phosphatidylinositol phospholipase C encoded by LB361 gene of L.interrogans ( L-PI-PLC) and its mechanism in inducing macrophage apoptosis .Meth-ods The PI-PLC domains in the sequence of LB 361 gene of L.interrogans serovar Lai strain were analyzed by bioinformatics method .Prokaryotic expression system was established to express the recombinant L -PI-PLC ( rL-PI -PLC).The enzymatic activity of rL-PI-PLC in hydrolyzing phosphatidylinositol -4,5-bisphos -phate (PIP2) substrate into inositol-1,4,5-trisphosphate (IP3) was determined by IP3 fluorescence polariza-tion assay.LB361gene expressions at mRNA and protein levels as well as the secretion of LB 361gene prod -ucts were detected by real-time fluorescent quantitative RT -PCR and Western blot assay after infection of hu-man THP-1 macrophages with L.interrogans serovar Lai strain.A LB361 gene-transfected THP -1cell line was generated for evaluation of the mechanism of LB 361 gene products in elevating intracellular free Ca 2+( [Ca 2+] i) concentration and inducing the apoptosis of transfected THP -1 cells with the use of laser confocal microscopy and flow cytometry.Re sul ts The rL-PI-PLC hydrolyzed PIP2 into IP3 with a Km of 199 μmol/L and a Kcat of 8.566×10-5 S-1 .The expressions of LB361gene at mRNA and protein levels were both signifi -cantly up-regulated after infection of THP-1 cells with L.interrogans serovar Lai strain .Moreover , the exter-nal secretion of L-PI-PLC was also found during infection .The concentrations of IP 3 and [ Ca2+] i in the LB361 gene-transfected THP-1 cells were significantly increased compared to those in the non-transfected THP-1 cells, resulting in a high [Ca2+]i-dependent apoptosis of partial THP-1 cells.Conclusion PI-PLC is encoded by the LB361 gene of L.interrogans, which could induce the apoptosis of macrophages through el-evating [ Ca2+] i concentration during infection of microphages with L.interrogans.
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Host genetic, environmental and viral factors are classified as three categories that determine clinical outcomes of hepatitis B virus (HBV) infection. The objective of this study was to detect the associations between polymorphisms rs346473 and rs346482 in Rho GTPase-activating protein 24 (ARHGAP24) gene and disease progression of HBV infection in Han Chinese population. These two SNPs were found by our DNA pooling using Affymetrix Genome-Wide Human Mapping SNP6.0 Array in HBV carriers, and verified by using TaqMan 7900HT Sequence Detection System with 758 progressed HBV carriers versus 300 asymptomatic HBV carriers (AsC) in a discovery phase and 971 progressed HBV carriers versus 328 AsC in a replication phase. Multivariable logistic regression revealed that individuals with genotype TT at variant rs346473 displayed remarkable correlations with disease progression of HBV infection both in the discovery phase (OR, 2.693; 95% CI, 1.928-3.760; P=6.2×10(-9); additive model) and the replication phase (OR, 1.490; 95% CI, 1.104-2.012; P=9.0×10(-3); additive model). These two SNPs were in strong linkage disequilibrium with D'=0.99 and r (2)=0.951, and haplotype TT disclosed an increased susceptibility to HBV progression (OR, 1.980; 95% CI, 1.538-2.545; P=8.1×10(-8)). These findings suggest that polymorphism rs346473 in the ARHGAP24 gene might be a part of the genetic variants underlying the susceptibility of HBV carriers to disease progression.
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Objective To investigate the expression of livin in hepatocarcinoma tissues and its relationship with hepatitis B virus X protein. Methods Immunohistochemistry was used to detect the expression of livin in 30 cases of hepatic carcinoma tissues and 10 cases of normal liver tissues. Stable L02 cell hne tansfected with HBx was established. Real-time PCR and Western blot were used to observe the expression of livin gene before and after the HBx transfeetion. Results The protein expression of livin was higher in hepatocarcinoma tissues than in normal tissues, and correlated with the exist of portal vein cancer embolus (t = 2.24, P = 0.033 ; P<0.05), but it was not correlated with cancer size or classification pathologically(t = 1.688, P = 0.103 ; γ = - 0.137, P = 0.471 ; P＞0.05). Livin Mrna expression was up-regulated after the HBx gene transfection (t = 6.73, P<0.05). Conclusions Apoptosis inhibition induced by livin up-regulation may play a role in pathogenesis and development of hepatocarcinoma. HBx up-regulates livin expression at transcriptional level.
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Objective To evaluate Chinese rural children's blood lead levels (BLLs) and identify its distribution features and to provide data for policy development to the prevention of rural environmental lead pollution. Methods The papers on rural children's BLLs published from 1994 to Oct, 2008 were collected by using CNKI's (China National Knowledge Infrastructure) Chinese Journal Full-test Database and other ways. The papers which were eligible for the following criteria were reviewed:(1) BLLs measured by atomic absorption spectroscopy (graphite or others) or inductively coupled plasma-mass spectrometry; (2) strict quality control; (3) no local lead pollution sources in the areas where the screened subjects live in; (4) children aged from 0 to 14 years old; (5)sample size more than 40. Results Analysis on the included 32 papers indicated that, the mean BLLs of Chinese rural children between 1994 and 2008 was 74.93 ?g/L ( range:41.14-193.54 ?g/L)and 19.32%( range:2.2%-43%) of the subjects had BLLs higher than 100 ?g/L. The rural children’s BLLs changed from 87.53 ?g/L to 71.16 ?g/L after the use of lead free gasoline in 2000 in China, which were both lower than the general children's BBLs before 2000 and after 2001. The children in Beijing city and Shandong province showed the highest mean BLLs , with 99.16 ?g/L and 92.13 ?g/L respectively; while the children in Jilin province and Hebei province showed the lowest levels, with 41.14 ?g/L and 56.14 ?g/L respectively. The comprehensive analysis of 18 papers indicated that the mean BLLs in rural areas and urban areas were 77.90 ?g/L and 87.24 ?g/L respectively ( u=3.73, P
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Lead is a kind of poisonous heavy metal which is widely existed in our environment. It is so harmful for children’s health. The whole society has paid much attention to this problem all the time. Blood lead level is an important index which can measure how seriously children have been exposed to lead. By consulting the papers on the studies of children's blood lead levels,the sources and influencing factors of blood lead levels of children in China were reviewed in the present paper,meanwhile,some suggestions were provided to decrease the lead contact probability and improve children's health.
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Objective To describe the relationship between ambient air pollutants(TSP,SO2,NOx) and the level of children’s lung function (FVC,FEV1,MMEF) in China. Methods The papers on ambient air pollution and children lung function published from 1985 to 2006 were collected and 11 of them were selected according to the following criteria: children aged 7-15; local air quality monitoring results were reported; strict quality control were taken when testing children lung function; the results were expressed by the average of measure. Results The selected papers included the results of 7 cities in China. Among them,the result of 6 cities showed that the levels of children lung function were significantly lower in the heavy air pollution areas compared with that in the light pollution areas. According to the papers,the average levels of ambient air TSP were in the range of 0.084 mg/m3-0.835 mg/m3,SO2(cSO2) were 0.013 mg/m3-0.929 mg/m3,NOx were 0.044 mg/m3-0.229 mg/m3,there was a significant negative correlation between the levels of TSP and SO2 and children FVC and FEV1,as well as the levels of NOx and children MMEF,the correlation coefficients were as follows,-0.797(t=-4.384,P=0.001) between TSP and FVC,-0.693(t=-4.190,P
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Objective: To study the changes in the expression of lung resistance protein(LRP) mRNA after multiple hyperthermia and the sensitivity to Adriamycin in HepG2 cell. Methods: HepG2 cell were treated by ten repeated cycles of exposure at 42 degree for 60 minute once a day, and stable HepG2 cell was obtained after hyperthermia. Compared with control HepG2 cell without hyperthermia, Real- time PCR and Western Blot were facilitated to observe the expression of LRP gene, Growth inhibition of Adriamycin to two groups was studied by MTT assay. The sensitivity of cell to Adriamycin was analyzed. Mean fluorescence intensity of ADM were detected by flow cytometry, and the changes of hyperthermia on intracellular concentration of ADM were analyzed. Results: Compared with control HepG2 cell without hyperthermia, the mRNA and protein levels of LRP in HepG2 cell increased 4.01?0.23 and 4.67?0.36 times respectively. This difference was of statistical significance(P
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Objective To explore the feasibility for applying passive individual samplers to determine NO2 and SO2 in the air simultaneously and to monitor the levels of them in the indoor and outdoor air. Methods Ten households were selected in urban and suburban area of Beijing respectively. Passive individual sampler made by Green blue Co. in Japan was used to sample and the ion chromatographic technique was used to determine the concentration of NO2 and SO2. Results There was no significant difference had been seen between the NO2 and SO2 level monitored by passive sampler and by the assay recommended by the national standard. It showed that the levels of NO2 and SO2 in ambient air were higher that that in indoor air, both indoor and outdoor air pollution in the urban area was more serious than that in the suburban area. The outdoor sulfur dioxide concentration in the urban area in winter was as 3.14 times high as that in the suburban area in 2001. The level of sulfur dioxide in the urban ambient air in 2002 was much lower than that in 2001. Conclusion Passive individual samplers with molecular diffusion will be suitable for environmental quantity monitoring.
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Computer-administered neurobehavioral evaluation system (NES)was developed based on the neurobehavioral core test battery (NCTB)recommended by WHO/NIOSH in 1985. Compared with NCTB,the reliability and validity of NES was much improved and some disadvantages of NCTB were made up in NES. This article reviewed the history of NES development,its application in the evaluation of children's neurobehavioral functions and its defects. The studies suggested that some items of NES test,such as finger tapping,continuous performance test and hand-eye coordination,could be used to evaluate earlier damage induced by chemicals on neurobehavioral functions of children.
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Objective To understand the effects of ambient air pollution on respiratory disease and symptoms among school-age children in Beijing and provide scientific basis for control and prevention of ambient air pollution in order to enhance the chidren's health. Methods The investigation was carried out in 3 areas(A, B, C) with ambient air pollution in different degrees of by different air pollution source in Beijing based on the data of environmental monitoring. 3 primary schools were selected in each investigation area. There were 5 749 observed pupils from 3 area in total. Investigation on respiratory health was performed by using the standard questionaire among pupils of Grade 1-Grade 5 in each school sampled by claster sampling method. Results The prevalences of respiratory disease and symptoms among children in A area with better ambient air quality were significantly lower than those in B area and C area with heavy ambient air pollution(P
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Objective To estimate the impact of cold wave on daily death of cerebra-cardiovascular diseases in Beijing by using case-crossover design. Methods The data of death counts was provided by Beijing Center for Disease Control and Prevention while the meteorological data was provided by Institute of Urban Meteorology,China Meteorological Administration (CMA),Beijing. The impact of six cold waves from Jan 1,1998 to Jun 30,2000 on daily death of cerebra-cardiovascular diseases were analyzed by using 1∶1 one-directional retrospective design and 1∶2 bi-directional symmetry control design. The cases were the people who dead during winter. Controls were the seventh day before or after the date of cases (or the fourteenth day). Results There were six cold waves in the investigation duration. The third cold wave in which minimum temperature declined obviously with decreasing humidity and increasing air pressure had significantly statistical significance in OR and the lag time of this cold wave was 0 day,the OR values were 1.500 (95%CI:1.032-2.181) for cardiovascular disease (CVD),respectively 1.913 (95%CI:1.066-3.432) for acute myocardial infarction,1.679 (95%CI:1.139-2.474) for cerebra-vascular disease(CBD) respectively. The other five cold waves do not have significant impact on cerebra-cardiovascular diseases. Conclusion Most cold waves studied in Beijing do not impact the daily death counts caused by cerebra-cardiovascular diseases. The cold wave with significant increased air pressure may increase the risk of death of cerebra-cardiovascular diseases without any lag time in Beijing.
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Objective To evaluate Chinese children’s blood lead levels(BLLs) and identify the distribution features with time and to provide the data for developing the policy to control environmental lead pollution.Methods The papers on children BLLs published from 2004 to Aug.2007 with sampling time since 2001 were collected,by searching Chinese Biomedical Disk(CBMDisk),Chinese Journal Full-test Database(CJFD) and other ways.Thirty-five articles eligible for inclusion criteria were reviewed.Also,the data were compared with our former study carried out in 2004 with articles studying time between 1995 and 2003.Results The mean BLL of Chinese children between 2001 and 2007 was 80.7 ?g/L(45.5-165.3 ?g/L),and 23.9%(3.2%-80.7%)were higher than 100 ?g/L,both of which were lower than the levels in 1995 to 2003.Four of 24 provinces or cities reported had average BLLs≥100 ?g/L.Of the 24 provinces or cities,only four had higher BLL and prevalence rates of lead poisoning(BLL ≥100 ?g/L) than that in 1995 to 2003.The mean BLL of children living in industrial areas was higher than that of children in urban and suburbs areas,and the mean BLL in suburbs was higher compared with urban areas.Boys BLL was 79.3 ?g/L,significantly higher than girls(76.9 ?g/L)(P
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Objective To analyze the relationship between children's respiratory health and ambient air pollution in China.Methods The studies on ambient air pollution and children's respiratory health in China published from 1980 to 2008 were collected and 12 of them were selected.Pearson correlation and linear regression analysis were used to find the correlations between levels of air pollutants and children's history prevalence of respiratory diseases and symptoms.Results Strong associations between the levels of TSP and the history prevalence of cough, long-term cough, sputum, long-term sputum, bronchitis for children were found, and 0.50%,0.12%,0.43%,0.09% and 0.51% increased respectively as per 10 ?g/m3 increased for TSP;there were significant associations between the levels of PM10 and the history prevalence of cough, sputum and bronchitis for children, and 2.64%, 2.27%,2.17% increased respectively as per 10 ?g/m3 increased for PM10.Significant associations were also found between the levels of PM2.5 and the history prevalence of cough, sputum and bronchitis for children, and 4.56%,3.49%, 3.74% increased respectively as per 10 ?g/m3 increased for PM2.5.Pearson correlation analysis indicated a significant increase of the history prevalence of wheeze for children with increase of levels of SO2;there were significant associations between the increase of the levels of SO2 and increase of the history prevalence of cough and sputum for children as the levels of SO2 lower than 0.15 mg/m3 , and 1.65% and 1.50% increased respectively as per 10 ?g/m3 increase of SO2.Significant associations between the levels of NOx lower than 0.10 mg/m3 and the history prevalence of long-term cough, long-term sputum, bronchitis for children were found, and 0.86%, 0.51% and 3.21% increased respectively as per 10 ?g/m3 increase of NOx.Furthermore, the associations between air pollutants and the history prevalence of children's respiratory health in north China were more significant.Conclusion The air pollutants in China are risk factors of children's respiratory system health, and impacts of air pollutants on children's respiratory system health in north China is more significant than that of the whole regions.
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In recent years, neurobehavioral end point was often used in environmental epidemiological researches to assess and characterize the adverse effects of environmental pollutants. The applications of neurobehavioral evaluation not only improve the ability to identify the early, sub clinic adverse effects of environmental pollutants exposure, but also help to screen out the victims for further protection. At present, there are many neurobehavioral evaluation methods have been applied in the environmental epidemiological researches at home and abroad, some methods that are considered applicable in China were reviewed in this article.
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Objective To describe blood lead levels (BLLs) and the distribution character of children in China as a whole. Methods The research papers on children's BLLs published in 1994-Mar,2004 were collected through Chinese Biomedical Disc(CBMDisc) or other ways, and 32 papers were selected into the present analysis according to the four main criteria: (1) BLLs were measured by graphite atomic absorption spectroscopy (GFAAS) or inductively coupled plasma-mass spectrometry(ICP-MS); (2) high quality guarantee and quality control were reported, standard substance using was necessary; (3)there were no local lead pollution resources in the areas where the involved children lived in; (4)the samples were more than 100. Results The mean BLL of Chinese children was 92.9 ?g/L(37.2-254.2 ?g/L)and 33.8%(9.6%-80.5%)of children, as for individual BLL, were higher than 100 ?g/L. It indicated that BLLs in boys were significantly higher than that in girls(P