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 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 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 compare the result of T2/T3 transitional cell carcinoma (TCC) of the urinary bladder after segmental cystectomy, treated by postoperative radiation plus intravesical chemotherapy and postoperative intravesical chemotherapy alone.Methods From 1985 to Dec.1995 patients with T2/T3 TCC bladder cancer who had been treated by segmental cystectomy were eligible for this retrospective analysis. Fifty-eight patients received postoperative radiotherapy plus intravesical chemotherapy (RT+IVC) and 35 patients were given postoperative intravesical chemotherapy (IVC) with thio-TEPA or calmette-Gue'rin bacilli (BCG). For radiation,8 or 18 ?MV X-ray was given with total dose of 50-60 ?Gy. Vesicoclysis was performed on 50-60 mg thio-TEPA twice per week and 0.5 mg BCG per week.Results The 3-year local control rates of RT+IVC and IVC groups were 68.6% and 48.2% showing a difference statistically significant (? 2=4.08,P=0.044).The 3- and 5-year survival rates of RT+IVC and IVC groups were 70.7%,49.5% and 59.9%,35.7% ,showing no significant difference (? 2=1.77,P=0.184). Among the 5 year survivors of the RT+IVC patients, 78.6% had their bladder preserved. Though untoward radiation reactions were severer, they were tolerated well.Conclusions Combined radiation therapy plus intravesical chemotherapy is indicated for T2/T3 bladder cancer after segmental cystectomy. Multimodality therapy is more favored to improve both the local control and the possibility of preserving the bladder.

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

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.

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.

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.

Objective:To study the concentrations of fine particulate matters and ultrafine particles and influenced factors during winter in an area of Beijing .Methods:Real-time monitoring of particles ’ mass and number concentrations were conducted in an area of Beijing from February 7th to 27th , 2013.At the same time, the meteorological data were also collected from the Beijing meteorological website .Differences of the particles ’ mass and number concentrations during different periods were analyzed using Mann -Whitney U test.Meanwhile, the influenced factors were also analyzed .Results: The mean concentra-tions of fine particulate matters and ultrafine particles were ( 157.2 ±142.8 ) μg/m3 and (25 018 ± 9 309) particles/cm3, respectively.The particles’ number and mass concentrations in haze days were 1.27 times and 2.91 times higher than those in non-haze days, respectively.The mass concentrations of fine particulate matters in the self-monitoring site were higher than those in the nearest central monitoring sites, and the hourly-average concentrations of particles were significantly consistent with those at the commuter times.Meanwhile, the setting off of fireworks/firecrackers during the Spring Festival could lead to short-term increases of the particles ’ number and mass concentrations .When the wind speed was low and the related humidity was high , the concentrations of particulate matters were relatively high , and the mass concentrations of fine particulate matters were lagged about 1-2 d.Conclusion: The level of the particulate matters in this area was high .Heavy traffic , setting off of fireworks/firecrackers and meteoro-logical factors may be some of the main factors affecting the concentrations of the particulate matters in this area.Among those factors, the effect of setting off of fireworks/firecrackers didn’t last long and the effect of the meteorological factors had a hysteresis effect .