With the rapid economic growth and the development of transportation in China in recent two decades, the number of motor vehicles in China keeps increasing at an annual rate of approximately 13%. The air pollution related to traffic has become the focus of attention and the air pollution pattern in some large cities in China has been shifting from the coal-burning pollution to that mainly from the traffic. The traffic pollution deteriorates the environment and has been related to an increased risk of respiratory and cardiovascular diseases in the population. The state of automobile exhaust pollution and the related health effect in the urban areas of China was discussed in the present paper.

Objective To investigate the effects of PM2.5 on gap junctional intercellular communication (GJIC) between rat cardiomyocytes. Methods Primary cultured cardiomyocytes were prepared from 1-day-old Sprague-Dawley rats and exposed to PM2.5(1,10,100 ?g/ml)for 24 hours. The GJIC between cardiomyocytes was detected by the scrape loading dye transfer assay. The distribution and density of connexin43(Cx43) in the cells was detected by indirect immunofluorescence and the expression of Cx43 was detected by western blotting. Results The gap junctional intercellular communication between cardiomyocytes was significantly inhibited by PM2.5 in a dose-dependent manner. The fluorescence density of Cx43 was significantly decreased in PM2.5-treated cells,and the expression of Cx43 was also slightly decreased. Conclusion PM2.5 can inhibit GJIC between cardiomyocytes,which may be mediated by the decreased expression and aberrant distribution of Cx43 in PM2.5-treated cells.

Objective To estimate the effect of ambient air pollution on cardiovascular related blood indicators in occupational,highly-exposed population in Beijing. Methods The blood samples were collected for twice from 14 taxi drivers in spring(15-16 April) and autumn(17 September) of 2008,respectively. The air pollution index before the sampling days was also collected for three months in each season. Results Ambient air quality was better in autumn than spring of 2008. The level of plasma viscosity was lower and levels of low-/high-density lipoproteins were higher in autumn compared with those of taxi drivers in spring. Conclusion Air pollution is positively associated with plasma viscosity and negatively associated with low-/high-density lipoproteins in occupational,highly-exposed individuals.

Objective To evaluate personal exposure level to PM2.5 of children living in one of districts of Beijing and to explore the possible influencing factors. Methods Thirty-six pupils were chosen from a primary school in the district. The PM2.5 level of classrooms,campuses and children's living rooms were monitored by Aerosol Monitor and 24 h time-active pattern and environmental information of living room of these pupils were collected at the same time. Each child's exposure level of PM2.5 was calculated by combining the environment PM2.5 monitor data and the children's 24 h time-active pattern. The possible influencing factors were analyzed by single factor analysis(Kruskal-Wall rank sum test and Spearman rank correlation analysis) and multiple linear regression models. Results The 24 h average exposure level of PM2.5 of 36 pupils was 98.13 ?g/m(341.22～121.13 ?g/m3) . The single factor analysis showed that the personal exposure level to PM2.5 was significantly related with air pollution index(API) (r =0.836,P

Objective:To investigate the effects of nanoscale titanium dioxide(Nano-TiO2) on gap junctional intercellular communication(GJIC) between human lung fibroblasts.Methods: Human lung fibroblasts were exposed to two different sizes Nano-TiO2(25 nm and 80 nm) for 24 hours at the concentrations of 0,10,20,40 and 80 mg/L,respectively.The GJIC between cells was measured by using fluorescence redistribution after photobleaching(FRAP) assay.Results: The results showed that GJIC between cells was significantly inhibited both by 25 nm and 80 nm Nano-TiO2 in a dose-dependent manner.The fluorescence recovery rate was 20.81%?1.93% in control group,7.26%?0.91%(P

Objective To study the acute effects of PM2.5 on the heart rhythm of spontaneously hypertensive rats(SHR)and the mechanism.Methods Twenty-eight male spontaneously hypertensive rats(SHR)were randomly divided into four groups.PM2.5 was administered by intratracheal instillation at the doses of 0 mg/kg,7.5 mg/kg,15 mg/kg and 30 mg/kg respectively.ECGs were monitored at 30 min,1 h and 24 h later.Results The numbers of the rats with arrhythmia in all groups increased at 30 min after treatment.At 1 h after treatment,in control group the rats recovered,but in PM2.5 groups abnormal ECGs was still showed.However,ECGs of all groups became normal 24 h later.As shown by laser scanning confocal microscope(LSCM),the expression of Cx43 in the heart tissue of rats in 15 mg/kg and 30 mg/kg groups significantly decreased compared with the control group.There was no significant change in content of MDA and SOD in the heart tissue of PM2.5 treated rats.Conclusion PM2.5 exposure through inhalation may induce arrhythmia in SHR rats and the downregulated expression of Cx43 may play an important role in the pathogenesis.

Objective To compare the results of three different types of fine particulate matter laser light scattering aerosol monitors and to explore the influencing factors.Methods Three types of Aerosol Monitor A, B, and C were used to monitor the mass concentration of indoor PM2.5 at the same time and place and the membrane weighing method was used at the same time.In order to explore the possible impacts of temperature and humidity indoor on the results of monitoring, a simultaneous monitoring on the temperature and humidity indoor was conducted.The sampling continued 2 days and with 23 hours per day.Results The results of PM2.5 monitored by the three types of aerosol monitors had a good consistency(r were 0.965, 0.988, and 0.984 respectively), but there was significant difference among them(P

Objective: To investigate the effect of silver nanoparticles (AgNPs) on hemichannel activity in human skin keratinocytes (HaCaT) and to explore the role of hemichannel in AgNP-induced anti-proliferative effect on HaCaT cells.Methods: HaCaT cells were exposed to 0, 0.1, 0.2, 1.0, 5.0, 10.0, 15.0 and 20.0 μg/cm2 of AgNPs for 24 h and cell viability was assessed by propidium iodide (PI) staining with flow cytometry.Hemichannel activity was examined by ethidium bromide (EB) uptake experiments in cells exposed to AgNPs with and without hemichannel inhibitor carbenoxolone (CBX).Afterward, HaCaT cells were seeded at a low density of 1×104cell /cm2 or a normal density of 4×104cell /cm2 and cultured for 24 h.Cell proliferation was measured by cell counting kit-8 (cck-8) in low-or normal-density cultured cells exposed to AgNPs for 24 h with and without 100 μmol/L CBX.Results: Cell viability showed no significant differences between the control and AgNP-exposed groups with the concentration less than 10 μg/cm2.Exposure to AgNPs increased EB uptake in a time-and dose-dependent manner in HaCaT cells and EB fluoresce density was increased to 116.67%, 124.85% and 139.53% of the control after exposure to 10 μg/cm2 AgNPs for 2 h, 12 h and 24 h.After being treated with 25, 50 and 100 μmol/L CBX, 10 μg/cm2 AgNP-induced increase in EB uptake was significantly reduced in HaCaT cells (P<0.01).The cellular proliferation rate was increased inlow-and normal-density cultured cells after AgNPs exposure with 100 μmol/L CBX.After being treated with 100 μmol/L CBX, 10 μg/cm2 AgNP-induced anti-proliferation in low-density cultured cells was significantly restrained (P<0.01).Conclusion: AgNPs could enhance hemichannel activity of HaCaT cells.Hemichannel activation was involved in AgNP-induced anti-proliferative effect.

Part of undergraduates were recruited from the universities round Xueyuan Road, Haidian district in Beijing. Self-administered questionnaire were conducted, on the basis of the status quo of students in understanding the environmental and health knowledge, attitude, behavior (KAP), to analyse the need for environmental health educational courses setting among undergraduates and to afford related suggestions on contents and methods for the course.

ObjectiveTo aim at the deficiencies of existing assessment methods,and put forward ideas,methods and contents to reform experimental course assessment methods for undergraduates.MethodsAll of the fifth-grade preventive medicine undergraduates were divided into experimental group (n=34) and control group(n=31),reformed and conventional assessment methods were used in experimental group and control group respectively.The difference in attendance,experimental skill and reports were compared between two groups.ResultsAttendance,test scores and experimental skill scores of students in experimental group were significantly higher than that in control group and compared with the control group students (P＜0,05),the experimental group students' understanding on the experimental principle,phenomena and data analysis were better.ConclusionReformed assessment methods of experimental course has an improved effect on teaching for undergraduates.