China has the largest production and consumption of tobacco worldwide. It has witnessed a dramatic increase in tobacco consumption over the past two decades, with more than 34.8 million cartons of cigarettes being produced and 34.7 million sold annually. Approximately 67% of males and 4% of females aged over 15 years in China are smokers, and the total of over 320 million Chinese smokers represents about one-third of all smokers worldwide. The continuous, rapid increase in the number of Chinese smokers is largely due to teenagers taking up smoking. Among teenagers aged 15-19 years, 18% of men and 0.28% of women (making a total of 9 million teenagers) are smokers. The prevalence of passive smoking is very high at 53.5%, about 0.3 billion people aged above 15 years were affected. The average daily consumption of tobacco per person in China rose from one cigarette in 1952 to 10 cigarettes in 1990, a rate similar to that of the USA 40 years earlier. It seems inevitable that China will witness a substantial increase in mortality following this increase in smoking. Based on current smoking rates, the predicted deaths attributed to smoking in China will rise to 3 million in 2050. If the current smoking pattern in China remains unchanged, 100 million men now under 30 years will die from smoking-related diseases. The respiratory system is harmed most by tobacco smoke. Over two-thirds of all deaths related to smoking in China are attributed to chronic obstructive pulmonary disease (COPD), lung cancer and pulmonary tuberculosis. The morbidity of COPD alone in China is estimated at over 3%, or 25 million people, of whom 72% were smokers. The Chinese government consistently supports smoking control and advocates smoking abstinence via laws to restrain the sale and advertising of tobacco. These actions have been successful in some aspects, and in particular, more people are aware that 'cigarette smoking is harmful to health'. In future, the emphasis of smoking control should be directed at restraining teenagers and adolescents from smoking. Cigarette smoking has already caused significant ill-health to the Chinese population with over 1 million people dying each year of various disorders caused by smoking. However, the peak of smoking-induced diseases is still to come and therefore, it is very important to strengthen anti-smoking measures so as to have a far-reaching effect on the future health of the Chinese population.

The mammalian target of rapamycin (mTOR) signaling pathway in pulmonary fibrosis was investigated in cell and animal models. mTOR overactivation in alveolar epithelial cells (AECs) was achieved in the conditional and inducible Tsc1 knock-down mice SPC-rtTA/TetO-Cre/Tsc1 fx/+ (STT). Doxycycline caused Tsc1 knock-down and consequently mTOR activation in AECs for the STT mice. Mice treated with bleomycin exhibited increased mortality and pulmonary fibrosis compared with control mice. In wild-type C57BL/6J mice, pretreatment with rapamycin attenuated the bleomycin-mediated mortality and fibrosis. Rapamycin-mediated mouse survival benefit was inhibited by chloroquine, an autophagy inhibitor. Autophagosomes were decreased in the lungs after bleomycin exposure. Rapamycin induced the production of autophagosomes and diminished p62. We concluded that mTOR overactivation in AECs and compromised autophagy in the lungs are involved in the pathogenesis of pulmonary fibrosis. The suppression of mTOR and enhancement of autophagy may be used for treatment of pulmonary fibrosis.

BackgroundKnowledge of predominant microbial patterns in community-acquired pneumonia (CAP) constitutes the basis for initial decisions about empirical antimicrobial treatment, so a prospective study was performed during 2003–2004 among CAP of adult Chinese urban populations.MethodsQualified patients were enrolled and screened for bacterial, atypical, and viral pathogens by sputum and/or blood culturing, and by antibody seroconversion test. Antibiotic treatment and patient outcome were also assessed.ResultsNon-viral pathogens were found in 324/610 (53.1%) patients among whom M. pneumoniae was the most prevalent (126/610, 20.7%). Atypical pathogens were identified in 62/195 (31.8%) patients carrying bacterial pathogens. Respiratory viruses were identified in 35 (19%) of 184 randomly selected patients with adenovirus being the most common (16/184, 8.7%). The nonsusceptibility of S. pneumoniae to penicillin and azithromycin was 22.2% (Resistance (R): 3.2%, Intermediate (I): 19.0%) and 79.4% (R: 79.4%, I: 0%), respectively. Of patients (312) from whom causative pathogens were identified and antibiotic treatments were recorded, clinical cure rate with β-lactam antibiotics alone and with combination of a β-lactam plus a macrolide or with fluoroquinolones was 63.7% (79/124) and 67%(126/188), respectively. For patients having mixed M. pneumoniae and/or C. pneumoniae infections, a better cure rate was observed with regimens that are active against atypical pathogens (e.g. a β-lactam plus a macrolide, or a fluoroquinolone) than with β-lactam alone (75.8% vs. 42.9%, p = 0.045).ConclusionIn Chinese adult CAP patients, M. pneumoniae was the most prevalent with mixed infections containing atypical pathogens being frequently observed. With S. pneumoniae, the prevalence of macrolide resistance was high and penicillin resistance low compared with data reported in other regions.