STROBE-Long-Term Exposure to Ambient Fine Particulate Air Pollution and Hospitalization Due to Peptic Ulcers

Little is known about the effect of air pollution on the gastrointestinal (GI) system. We investigated the association between long-term exposures to outdoor fine particles (PM2.5) and hospitalization for peptic ulcer diseases (PUDs) in a large cohort of Hong Kong Chinese elderly.A total of 66,820 subjects aged ≥65 years who were enrolled in all 18 Government Elderly Health Service centers of Hong Kong participated in the study voluntarily between 1998 and 2001. They were prospectively followed up for more than 10 years. Annual mean exposures to PM2.5 at residence of individuals were estimated by satellite data through linkage with address details including floor level. All hospital admission records of the subjects up to December 31, 2010 were retrieved from the central database of Hospital Authority. We used Cox regression to estimate the hazard ratio (HR) for PUD hospitalization associated with PM2.5 exposure after adjustment for individual and ecological covariates.A total of 60,273 subjects had completed baseline information including medical, socio-demographic, lifestyle, and anthropometric data at recruitment. During the follow-up period, 1991 (3.3%) subjects had been hospitalized for PUD. The adjusted HR for PUD hospitalization per 10 μg/m of PM2.5 was 1.18 (95% confidence interval: 1.02-1.36, P = 0.02). Further analysis showed that the associations with PM2.5 were significant for gastric ulcers (HR 1.29; 1.09-1.53, P = 0.003) but not for duodenal ulcers (HR 0.98; 0.78 to 1.22, P = 0.81).Long-term exposures to PM2.5 were associated with PUD hospitalization in elder population. The mechanism underlying the PM2.5 in the development of gastric ulcers warrants further research.

Health impact assessment of exposure to fine particulate matter based on satellite and meteorological information

Air pollution in China, especially in the Pearl River Delta (PRD) region, has drastically increased in recent years. We modelled annual mean ground-level PM2.5 concentrations based on worldwide satellite information and meteorological data from 40 cities outside the PRD. The model of PM2.5 concentration (R = 0.845) was best explained by aerosol optical thickness (43.8%). We validated the spatial-temporal dimensions of the model and estimated that the annual mean PM2.5 concentration in PRD ranged between 22 and 65 μg m(-3). Then we used meta-analysis to obtain the pooled excess risks of mortality in China and assessed the health impacts. We found an inverse association between short-term excess risks of mortality and annual mean PM2.5 concentrations. Based on the above models and analyses, the associated excess deaths for all-cause and cardiopulmonary diseases were 3386 and 2639 respectively. The corresponding risk-standardized excess death rates were 2006 and 1069 per million people.

The impact of hepatitis B virus (HBV) infection on clinical outcomes of patients with diffuse large B-cell lymphoma

We performed a retrospective study to analyse the characteristics and clinical outcomes of diffuse large B-cell lymphoma (DLBCL) patients with hepatitis B virus (HBV) infection and compare with those without HBV infection. The occurrence of hepatitis after withdrawal of prophylactic antiviral treatment on completion of chemotherapy was also assessed. The HBsAg-positive patients were given prophylactic antiviral treatment until 6 months after finishing chemotherapy. A total of 81 patients were recruited with 16 in the HBsAg-positive group and 65 in the HBsAg-negative group. The clinical characteristics were similar in both groups of patients. There was no significant difference in complete remission rate between the two groups (63% in HBsAg-positive group vs. 54% in HBsAg-negative group, P = 0.59). There was also no statistically significant difference in overall survival between the two groups (P = 0.23). Four of the 16 HBsAg-positive patients (25%) had hepatitis after cessation of chemotherapy and prophylactic lamivudine. The mean time of onset of hepatitis was 3 months after stopping lamivudine. In conclusion, HBV infection did not appear to affect the prognosis of DLBCL patients given antiviral prophylaxis. It is reasonable to consider prophylactic antiviral therapy to extend to at least one year on completion of chemotherapy.

A method to derive the relationship between the annual and short-term air quality limits--analysis using the WHO Air Quality Guidelines for health protection

The World Health Organization (WHO) Air Quality Guidelines (AQG) were launched in 2006, but gaps remain in evidence on health impacts and relationships between short-term and annual AQG needed for health protection. We tested whether relationships between WHO short-term and annual AQG for particulates (PM10 and PM2.5) and nitrogen dioxide (NO2) are concordant worldwide and derived the annual limits for sulfur dioxide (SO2) and ozone (O3) based on the short-term AQG. We obtained air pollutant data over seven years (2004-2010) in seven cities from Asia-Pacific, North America and Europe. Based on probability distribution concept using maximum as the short-term limit and arithmetic mean as the annual limit, we developed a new method to derive limit value one from another in each paired limits for each pollutant with capability to account for allowable exceedances. We averaged the limit derived each year for each city, then used meta-analysis to pool the limit values in all cities. Pooled mean short-term limit for NO2 (140.5μg/m(3) [130.6-150.4]) was significantly lower than the WHO AQG of 200μg/m(3) while for PM10 (46.4μg/m(3) [95CI:42.1-50.7]) and PM2.5 (28.6μg/m(3) [24.5-32.6]) were not significantly different from the WHO AQG of 50 and 25μg/m(3) respectively. Pooled mean annual limits for SO2 and O3 were 4.6μg/m(3) [3.7-5.5] and 27.0μg/m(3) [21.7-32.2] respectively. Results were robust in various sensitivity analyses. The distribution relationships between the current WHO short-term and annual AQG are supported by empirical data from seven cities for PM10 and PM2.5, but not for NO2. The short-term AQG for NO2 should be lowered for concordance with the selected annual AQG for health protection.

Thermal stress associated mortality risk and effect modification by sex and obesity in an elderly cohort of Chinese in Hong Kong

We assessed the effects of apparent temperature (AT) on mortality and the effect modifications attributable to individual characteristics in Hong Kong with subtropical climate conditions. Two datasets are used for analyses: one from mortality data of the general elderly population in 1998-2009; the other from an elderly cohort with 66,820 subjects recruited in 1998-2001 with mortality outcomes followed up until 2009. We found that AT below 20.8 °C was associated with an increase in mortality risk of 1.99% (95% confidence interval: 0.64%, 2.64%) for all causes, 2.48% (0.57%, 4.36%) for cardiovascular disease, and 3.19% (0.59%, 5.73%) for respiratory disease for every 1 °C decrease in AT over the following 3 days. The associations were modified by sex and body mass index, in particular stronger associations were observed for females and for obese subjects.

Meta-analysis of adverse health effects due to air pollution in Chinese populations

Background

Pooled estimates of air pollution health effects are important drivers of environmental risk communications and political willingness. In China, there is a lack of review studies to provide such estimates for health impact assessments.

Methods

We systematically searched the MEDLINE database using keywords of 80 major Chinese cities in Mainland China, Hong Kong and Taiwan on 30 June 2012, yielding 350 abstracts with 48 non-duplicated reports either in English or Chinese after screening. We pooled the relative risks (RR) per 10 μg/m³ of particulate matter (PM₁₀), nitrogen dioxide (NO₂), sulphur dioxide (SO₂) and ozone (O₃).

Results

For short-term effects, the pooled RR (p < 0.05) ranges were: 1.0031 (PM₁₀) to 1.0140 (NO₂) for all-cause mortality, 1.0034 (cardiopulmonary, PM₁₀) to 1.0235 (influenza and pneumonia, SO₂) for 9 specific-causes mortality, 1.0021 (cardiovascular, PM₁₀) to 1.0162 (asthma, O₃) for 5 specific-causes hospital admissions. For birth outcomes, the RR (p < 0.05) ranged from 1.0051 (stillbirth, O₃) to 1.1189 (preterm-birth, SO₂) and for long-term effect on mortality from 1.0150 (respiratory, SO₂) to 1.0297 (respiratory, NO₂). Publication bias was absent (Egger test: p = 0.326 to 0.624). Annual PM₁₀ and NO₂ concentrations were inversely associated with RR of mortality (p = 0.017-0.028).

Conclusions

Evidence on short-term effects of air pollution is consistent and sufficient for health impact assessment but that on long-term effects is still insufficient.

Effect of influenza on cardiorespiratory and all-cause mortality in Hong Kong, Singapore and Guangzhou

1. Using a common modelling approach, mortality attributable to influenza was higher in the two subtropical cities Guangzhou and Hong Kong than in the tropical city Singapore. 2. The virus activity appeared more synchronised in subtropical cities, whereas seasonality of influenza tended to be less marked in the tropical city. 3. High temperature was associated with increased mortality after influenza infection in Hong Kong, whereas relative humidity was an effect modifier for influenza in Guangzhou. No effect modification was found for Singapore. 4. Seasonal and environmental factors probably play a more important role than socioeconomic factors in regulating seasonality and disease burden of influenza. Further studies are needed in identifying the mechanism behind the regulatory role of environmental factors.

Use of radiosynovectomy in recurrent warfarin-related haemarthrosis in degenerative arthritis

Radiosynovectomy is a local and minimally invasive radiotherapy for treating various chronic inflammatory arthritis such as rheumatoid arthritis, osteoarthritis and haemophilic arthropathy. In haemophilic arthropathy, it reduces the frequency of haemarthrosis and delays the development of severe joint destruction, which ultimately requires surgical intervention. Its role in warfarin-related haemarthrosis is less clear. Haemarthrosis is an uncommon complication of warfarin use, and anticoagulation may need to be discontinued. We describe yttrium-90 radiosynovectomy use in a 74-year-old man with underlying ischaemic heart disease, atrial fibrillation, previous embolic stroke and recurrent haemarthrosis of an osteoarthritic right knee. Anticoagulation was vital and could not be permanently stopped. Due to continuing anticoagulation, he had multiple hospitalisations with recurrent right knee haemarthrosis. Intraarticular right knee yttrium-90 citrate colloid injection led to a cessation of haemarthrosis for eight months. We examined the available literature for the role of radiosynovectomy in such circumstances.

Lung function and exposure to workplace second-hand smoke during exemptions from smoking ban legislation: an exposure-response relationship based on indoor PM2.5 and urinary cotinine levels

BACKGROUND

The effects of workplace second-hand smoke (SHS) on lung function remain uncertain because of a lack of objective measures for SHS exposures.

OBJECTIVE

To determine whether an exposure-response association exists between lung function and two different markers of SHS based on indoor fine particulate (PM(2.5)) and urinary cotinine levels in non-smoking catering workers.

DESIGN

A cross-sectional study during a 1.5-year exemption of licensed catering premises from smoke-free legislation. Participants 186 non-smoking catering workers aged 18-65 years in Hong Kong were recruited. A declared non-smoking status was accepted in workers with exhaled breath carbon monoxide levels <6 ppm and urinary cotinine levels <100 ng/ml.

MAIN OUTCOME MEASURES

Lung function measures of forced expiratory volume in 1s (FEV(1) in litres), forced vital capacity (FVC in litres) and forced expiratory flow as 25-75% of FVC (FEF(25-75) in l/s) were recorded.

RESULTS

Indoor fine particulate (PM(2.5)) concentrations were 4.4 times as high in smoking premises (267.9 μg/m(3)) than in non-smoking premises (60.3 μg/m(3)) and were strongly associated with the probability of permitted smoking (R(2)=0.99). Smoking was the dominant source of particulates (R(2)=0.66). Compared with workers exposed to the lowest indoor PM(2.5) stratum (<25 μg/m(3)), lung function was lower in the three higher PM(2.5) strata (25-75, 75-175, >175 μg/m(3)) with FEV(1) -0.072 (95% CI -0.123 to -0.021), -0.078 (95% CI -0.132 to -0.024), -0.101 (95% CI -0.187 to -0.014); FEF(25-75) -0.368 (95% CI -0.660 to -0.077), -0.489 (95% CI -0.799 to -0.179), -0.597 (95% CI -0.943 to -0.251); and FEV(1)/FVC (%) -2.9 (95% CI -4.8 to -1.0), -3.2 (95% CI -5.1 to -1.4) and -4.4 (95% CI -7.4 to -1.3), respectively. Urinary cotinine was associated positively with indoor PM(2.5) but negatively with lung function. Consistently lower values for lung function per unit increase of indoor PM(2.5) were found.

CONCLUSION

Lung function is inversely associated with workplace SHS. Workplace exemptions and delays in implementing smoke-free policies and current moves to relax legislation are a major threat to the health of workers.

Exposure to secondhand smoke and academic performance in non-smoking adolescents

OBJECTIVE

To study the association between exposure to secondhand smoke (SHS) and academic performance in non-smoking adolescents.

STUDY DESIGN

A questionnaire survey of 23 052 non-smoking students aged 11 to 20 years was conducted. Information on academic performance, number of days of SHS exposure per week at home and outside the home, number of smokers at home and their relationship with the student, and sociodemographic characteristics was recorded.

RESULTS

Students exposed to SHS at home 1 to 4 and 5 to 7 days per week were 14% (95% confidence interval, 5%-25%) and 28% (15%-41%) more likely, respectively, to report poor academic performance compared with students who were not exposed to SHS. Living with one, two, and ≥ 3 smokers, compared with no smoker, was also associated with 10% (0.1%-20%), 43% (23%-65%) and 87% (54%-127%), respectively, higher odds of poor academic performance (P for trend <.001). The greatest excess risks were observed with SHS exposure from co-residing non-relatives, followed by siblings, visitors, co-residing grandparents and relatives, and parents.

CONCLUSION

SHS exposure is associated linearly with poor academic performance in non-smoking adolescents, and the effect of SHS exposure at home is stronger from smokers other than the parents.

'Carcinogens in a puff': smoking in Hong Kong movies

Smoking scenes in movies, exploited by the tobacco industry to circumvent advertisement bans, are linked to adolescent smoking. Recently, a Hong Kong romantic comedy Love in a puff put smoking at centre stage, with numerous smoking scenes and words that glamourise smoking. Although WHO has issued guidelines on reducing the exposure of children to smoking in movies, none is adopted in Hong Kong. Comprehensive tobacco control strategies are urgently needed to protect young people in Hong Kong from cigarette promotion in movies.

Exposure to particulate air pollution at different living locations and respiratory symptoms in Hong Kong--an application of satellite information

Respiratory ill-health effects due to particulate air exposure at different geographical locations in Hong Kong that aggregate individual living locations were estimated based on satellite information. We assessed the presence of respiratory symptoms of a frequent cough or sputum in school students aged 11-20 years old (n = 9,881). Daily particulate air pollution levels at students' living locations were derived from the surface extinction coefficients measured by satellite and measurements from the air pollutant monitoring stations at ground level. Adjusted odds ratio (OR) [95% CI] of respiratory symptoms was 1.047 [1.005, 1.091] per 10 microg m(-3) increase in PM(10) concentration. Specificity tests showed that adjusted OR of having other symptoms is not significant (p = 0.20-0.94). Exposures to PM(10) at different geographical locations is associated with increased odds of having respiratory symptoms (cough or sputum) but not with other symptoms unrelated to air pollution.

Secondhand smoke and respiratory symptoms among adolescent current smokers

OBJECTIVE

No study has ever reported the association between persistent respiratory symptoms and exposure to secondhand smoke (SHS) in adolescent smokers. The impact of SHS exposure on child health could be largely underestimated by not taking into account such effects. We investigated the association between exposure to SHS and respiratory symptoms among adolescent current smokers.

METHODS

A total of 32506 students aged 11 to 20 years from 85 randomly selected secondary schools in Hong Kong completed a self-administered questionnaire that included persistent respiratory symptoms (for 3 consecutive months in the past 12 months), number of days of SHS exposure per week at home and outside home, smoking status, amount of active smoking, and other basic demographic characteristics and socioeconomic status.

RESULTS

Adolescent current smokers who were exposed to SHS at home 1 to 4 and 5 to 7 days/wk were 50% (95% confidence interval [CI]: 3%-121%) and 77% (95% CI: 5%-199%) more likely, respectively, to report respiratory symptoms compared with those who were unexposed (P = .01 for trend). The corresponding figures for exposure outside home were 41% (95% CI: 3%-94%) and 85% (95% CI: 31%-161%; P = .004 for trend). Such associations were also observed among never-smokers, but they were weaker than those among current smokers (P < .01 for interaction).

CONCLUSIONS

This is the first evidence that SHS exposure is associated with increased risks for persistent respiratory symptoms among adolescent current smokers. Health promotion programs should aim at SHS reduction as well as smoking cessation among adolescent smokers.

A review of effects of particulate matter-associated nickel and vanadium species on cardiovascular and respiratory systems

Many epidemiological investigations indicate that excess risks of mortality and morbidity may vary among specific PM(2.5) components. Nickel (Ni) and vanadium (V) particulate metal species may potentially be related to increasing respiratory and cardiovascular mortality and morbidity. This review focuses on exposure concentrations of these two species in various settings, their health effects based on epidemiological and toxicological studies and the underlying mechanisms. The evidence shows that environmental exposure concentrations of Ni and V in general setting are lower than the World Health Organization standard (V, 1 microg/m(3)/day) in 2000, or the European Environment Agency standard (Ni, 1 microg/m(3)/day) in 2003, but their associations with cardiopulmonary diseases can still be found. The toxicological mechanism can be explained by laboratory-based studies. Updated safe guidelines on environmental and human exposure of Ni and V are necessary in order to clarify the associations between them and cardiopulmonary diseases and provide environmental intervention policies.

Is exercise protective against influenza-associated mortality?

BACKGROUND

Little is known about the effect of physical exercise on influenza-associated mortality.

METHODS AND FINDINGS

We collected information about exercise habits and other lifestyles, and socioeconomic and demographic status, the underlying cause of death of 24,656 adults (21% aged 30-64, 79% aged 65 or above) who died in 1998 in Hong Kong, and the weekly proportion of specimens positive for influenza A (H3N1 and H1N1) and B isolations during the same period. We assessed the excess risks (ER) of influenza-associated mortality due to all-natural causes, cardiovascular diseases, or respiratory disease among different levels of exercise: never/seldom (less than once per month), low/moderate (once per month to three times per week), and frequent (four times or more per week) by Poisson regression. We also assessed the differences in ER between exercise groups by case-only logistic regression. For all the mortality outcomes under study in relation to each 10% increase in weekly proportion of specimens positive for influenza A+B, never/seldom exercise (as reference) was associated with 5.8% to 8.5% excess risks (ER) of mortality (P<0.0001), while low/moderate exercise was associated with ER which were 4.2% to 6.4% lower than those of the reference (P<0.001 for all-natural causes; P = 0.001 for cardiovascular; and P = 0.07 for respiratory mortality). Frequent exercise was not different from the reference (change in ER -0.8% to 1.7%, P = 0.30 to 0.73).

CONCLUSION

When compared with never or seldom exercise, exercising at low to moderate frequency is beneficial with lower influenza-associated mortality.

Interaction of retinoic acid and interferon in renal cancer cell lines

Retinoic acid (RA) can potentiate the antitumor effect of interferons (IFN) in a variety of tumor types, including renal cell carcinoma (RCC). The mechanisms by which RA and IFN increase the antitumor effects in RCC are unknown. We used growth assays and mobility shift assays to examine the effects of combining 13-cis-retinoic acid (CRA) and IFN-alpha (plus IFN-gamma) on proliferation and on the expression of the IFN-specific transcription factor IFN-stimulated gene factor 3 (ISGF3) in RCC cell lines. Combining CRA and IFN-alpha resulted in a significant increase in growth inhibition in four cell lines compared with IFN-alpha or CRA alone. Binding of nuclear extracts from RCC cells to an IFN-stimulated response element (ISRE) oligonucleotide probe following incubation with IFN-alpha was not increased by CRA but was significantly increased by pretreatment by IFN-gamma in a time-dependent fashion. Proliferation assays showed that sequential addition of IFN-gamma and IFN-alpha significantly increased growth inhibition. IFN-alpha but not IFN-gamma or CRA increased the cellular levels Stat2 and p48 but not Statl. IFN-gamma pretreatment enhanced the upregulation of p48 levels by IFN-alpha. Combining RA and IFN results in additive growth inhibition on RCC cell lines. This increase in growth inhibition is not mediated by increased ISGF3 expression.

The promyelocytic leukemia (PML) protein suppresses cyclin D1 protein production by altering the nuclear cytoplasmic distribution of cyclin D1 mRNA

The majority of the promyelocytic leukemia (PML) protein is present in nuclear bodies which are altered in several pathogenic conditions including acute promyelocytic leukemia. PML nuclear bodies are found in nearly all cells yet their function remains unknown. Here, we demonstrate that PML and the eukaryotic initiation factor 4E (elF-4E) co-localize and co-immunopurify. eIF-4E is involved in nucleocytoplasmic transport of specific mRNAs including cyclin D1. eIF-4E overexpression leads to increased cyclin D1 protein levels; whereas, overexpression of PML leads to decreased cyclin D1 levels. Neither PML nor eIF-4E cause significant changes in cyclin D1 mRNA levels. The association with eIF-4E led us to investigate if PML could alter mRNA distribution as a possible post-transcriptional mechanism for suppressing cyclin D1 production. We show that overexpression of PML results in nuclear retention of cyclin D1 mRNA and that intact PML nuclear bodies are required. Addition of eIF-4E overcomes PML induced retention and alters the morphology of PML bodies suggesting a mechanism by which eIF-4E can modulate PML function. These results raise the possibility that PML nuclear bodies may participate in the regulation of nucleocytoplasmic transport of specific mRNAs.

Expression of the kidney-associated differentiation glycoprotein gp160 and resistance to the antitumor effects of interferon alpha in renal cell carcinomas

BACKGROUND

Alpha interferon (IFN-alpha) is commonly used to treat patients with advanced renal cell carcinoma (RCC). We previously reported that resistance of RCCs to IFN-alpha in vitro correlated with the expression of a cell-surface glycoprotein of 160,00 kD molecular weight (gp160) which we subsequently identified as aminopeptidase A.

MATERIALS AND METHODS

To directly test the role of gp160/APA in IFN-resistance, we stably introduced the gp160/APA cDNA into IFN-sensitive SK-RC-49 cells resulting in the expression of an enzymatically active gp160/APA protein. In addition, to determine if gp160/APA expression could function as a marker of IFN-resistance in vivo, we assessed gp160/APA protein levels in autologous normal kidney and primary renal cancer specimens from 29 patients half of which were randomized to receive adjuvant IFN-alpha therapy following nephrectomy.

RESULTS

Four clones which possessed varying amounts of gp160/APA specific enzyme activity were assayed for sensitivity to the antiproliferative effects of IFN-alpha. All four clones exhibited sensitivity to IFN-alpha similar to that observed with parental SK-RC-49 cells. The analysis of tumor tissue detected no significant difference between the mean level of gp160/APA in tissue from control and IFN-alpha treated patients (1.33 A.U. versus 0.9981 A.U., p = 0.23); however, the mean gp160/APA level was significantly less in tumor tissue (mean = 1.15 A.U.) compared to normal tissue (mean = 2.15 A.U.; p < 0.00001). Within the IFN-alpha treated group, tumor gp160/APA levels did not correlate with the development of metastases or survival (p = 0.469).

CONCLUSIONS

These data indicate that gp160/APA does not directly convey IFN-resistance to RCC cells and suggest that expression of gp160/APA in primary RCCs does not predict the benefit of IFN-alpha therapy.