Association between Ambient Air Pollution and Outpatient Visits for Acute Bronchitis in a Chinese City

Objective To investigate the short-term association between outdoor air pollution and outpatient visits for acute bronchitis,which is a rare subject of research in the mainland of China.Methods A time-series analysis was conducted to examine the association of outdoor air pollutants with hospital outpatient visits in Shanghai by using two-year daily data（2010-2011）.Results Outdoor air pollution was found to be associated with an increased risk of outpatient visits for acute bronchitis in Shanghai.The effect estimates of air pollutants varied with the lag structures of the concentrations of the pollutants.For lag06,a 10 μg/m3 increase in the concentrations of PM10,SO2,and NO2 corresponded to 0.94%（95% CI：0.83%,1.05%）,11.12%（95% CI：10.76%,11.48%）,and 4.84%（95% CI：4.49%,5.18%） increases in hospital visits for acute bronchitis,respectively.These associations appeared to be stronger in females（P〈0.05）.Between-age differences were significant for SO2（P〈0.05）,and between-season differences were also significant for SO2（P〈0.05）.Conclusion Our analyses have provided the first evidence that the current air pollution level in China has an effect on acute bronchitis and that the rationale for further limiting air pollution levels in Shanghai should be strengthened.

Lipoxygenase—mediated N—demethylation of imipramine and related tricyclic antidepressants

The ability of soybean lipoxygenase to mediate the N-demethylation of imipramine and related drugs in the presence of hydrogen peroxide was examined.Under optimal assay conditions,Vmax values of 14 to 18 mol formaldehyde·min^-1·mol^-1 enzyme were observed.An inhibition of formaldehyde and desipramine formation by nordihydroguaiaretic acid confirmed the lipoxygenase involvement.The blockade of the reaction by glutathione,dithiothreitol butylated hydroxyanisole (BHA) and butylated hydroxytoluene(BHT) indicated the generation of a free radical intermediate from imipramine.Desipramine,trimipramine,clomipramine,and diltiazem,but not amitriptyline and doxepin,were also oxidized,albeit at a lower rate.Collectively,the evidence gathered in this study suggests,for the first time,that tricyclic antidepressant drugs may undergo lipoxygenase-catalyzed N-demethylation.

Has Sperm Count Declined in the General Male Danish Population during the Last Several Decades?A Study on the Relation of Sperm Count and Birth Year

It has been hypothesized that during the last several decades human sperm count has declined because of prenatal exposure to environmental chemicals. We examined the relation between semen quality and birth year among 8608 men born from 1922 to 1971 and who from 1968 to 1992 consulted 4 Danish medical centers because of barren marriage. Data were obtained from medical records and by a postal questionnaire to a subset of the population. The sperm concentration was significantly declining with increasing year of birth in 2 of the 4 centers, but this association disappeared when confounders were adjusted for. Within the subset of men born during 1955~1970 comprising 36% of the entire population we revealed a decrease of the average sperm concentration by 1.6 million /ml (95% CI:0.7~2.5) per one advancing year of birth.This finding was consistent across all the 4 centers and robust to adjustment for effects of calendar period, season and duration of sexual abstinence. Effects of age were accounted for by restriction of the sample to men between 20 and 45 years. The findings are compatible with environmental impact in the prenatal period after 1955 but are far from unequivocal evidence that the sperm count in the general male Danish population has changed during the past decades.