Chemical Investigation of Household Solid Fuel Use and Outdoor Air Pollution Contributions to Personal PM2.5 Exposures.

In communities with household solid fuel use, transitioning to clean stoves/fuels often results in only moderate reductions in fine particulate matter (PM2.5) exposures; the chemical composition of those exposures may help explain why. We collected personal exposure (men and women) and outdoor PM2.5 samples in villages in three Chinese provinces (Shanxi, Beijing, and Guangxi) and measured chemical components, including water-soluble organic carbon (WSOC), ions, elements, and organic tracers. Source contributions from chemical mass balance modeling (biomass burning, coal combustion, vehicles, dust, and secondary inorganic aerosol) were similar between outdoor and personal PM2.5 samples. Principal component analysis of organic and inorganic components identified analogous sources, including a regional ambient source. Chemical components of PM2.5 exposures did not differ significantly by gender. Participants using coal had higher personal/outdoor (P/O) ratios of coal combustion tracers (picene, sulfate, As, and Pb) than those not using coal, but no such trend was observed for biomass burning tracers (levoglucosan, K+, WSOC). Picene and most levoglucosan P/O ratios exceeded 1 even among participants not using coal and biomass, respectively, indicating substantial indirect exposure to solid fuel emissions from other homes. Contributions of community-level emissions to exposures suggest that meaningful exposure reductions will likely require extensive fuel use changes within communities.

High-Ambient Air Pollution Exposure Among Never Smokers Versus Ever Smokers With Lung Cancer.

INTRODUCTION: Air pollution may play an important role in the development of lung cancer in people who have never smoked, especially among East Asian women. The aim of this study was to compare cumulative ambient air pollution exposure between ever and never smokers with lung cancer. METHODS: A consecutive case series of never and ever smokers with newly diagnosed lung cancer were compared regarding their sex, race, and outdoor and household air pollution exposure. Using individual residential history, cumulative exposure to outdoor particulate matter (PM2.5) in a period of 20 years was quantified with a high-spatial resolution global exposure model. RESULTS: Of the 1005 patients with lung cancer, 56% were females and 33% were never smokers. Compared with ever smokers with lung cancer, never smokers with lung cancer were significantly younger, more frequently Asian, less likely to have chronic obstructive pulmonary disease or a family history of lung cancer, and had higher exposure to outdoor PM2.5 but lower exposure to secondhand smoke. Multivariable logistic regression analysis revealed a significant association with never-smoking patients with lung cancer and being female (OR = 4.01, 95% confidence interval [CI]: 2.76-5.82, p < 0.001), being Asian (ORAsian versus non-Asian = 6.48, 95% CI: 4.42-9.50, p < 0.001), and having greater exposure to air pollution (ORln_PM2.5 = 1.79, 95% CI: 1.10-7.2.90, p = 0.019). CONCLUSIONS: Compared with ever-smoking patients with lung cancer, never-smoking patients had strong associations with being female, being Asian, and having air pollution exposures. Our results suggest that incorporation of cumulative exposure to ambient air pollutants be considered when assessing lung cancer risk in combination with traditional risk factors.

Determinants of personal exposure to PM2.5 and black carbon in Chinese adults: A repeated-measures study in villages using solid fuel energy.

Exposure to air pollution is a leading health risk factor. The variance components and contributions of indoor versus outdoor source determinants of personal exposure to air pollution are poorly understood, especially in settings of household solid fuel use. We conducted a panel study with up to 4 days of repeated measures of integrated gravimetric personal exposure to PM2.5 and black carbon in 787 men and women (ages 40-79) living in peri-urban villages in northern (Beijing and Shanxi) and southern (Guangxi) China. We simultaneously measured outdoor PM2.5 and collected questionnaire data on sociodemographic characteristics and indoor pollution sources including tobacco smoking and solid fuel stove use. We obtained over 2000 days of personal exposure monitoring which showed higher exposures in the heating season (geometric mean (GM): 108 versus 65 µg/m3 in the non-heating season for PM2.5) and among northern participants (GM: 90 versus 59 µg/m3 in southern China in the non-heating season for PM2.5). We used mixed-effects models to estimate within- and between-participant variance components and to assess the determinants of exposures. Within-participant variance in exposure dominated the total variability (68-95%). Outdoor PM2.5 was the dominant variable for explaining within-participant variance in exposure to PM2.5 (16%). Household fuel use (PM2.5: 8%; black carbon: 10%) and smoking status (PM2.5: 27%; black carbon: 5%) explained the most between-participant variance. Indoor sources (solid fuel stoves, tobacco smoking) were associated with 13-30% higher exposures to air pollution and each 10 µg/m3 increase in outdoor PM2.5 was associated with 6-8% higher exposure. Our findings indicate that repeated measurements of daily exposure are likely needed to capture longer-term exposures in settings of household solid fuel use, even within a single season, and that reducing air pollution from both outdoor and indoor sources is likely needed to achieve measurable reductions in exposures to air pollution.

Vertical monitoring of traffic-related air pollution (TRAP) in urban street canyons of Hong Kong.

Rapid urbanization has significantly increased air pollution especially in urban regions with high traffic volumes. Existing methods for estimating traffic-related air pollution (TRAP) and TRAP-related health impacts are based on two-dimensional modelling. This paper describes a point-based methodology to monitor vertical pollutant concentrations in typical street canyons of Hong Kong. It explains the conceptual design, monitoring strategy and selection criteria for a limited number of receptor locations in street canyons to undertake field measurements for both outdoor exposure and indoor infiltration. It also expounds on the limitations and complications associated with field instrumentation and retention of participating home units. The empirical results were applied on the building infiltration efficiencies assessment. It is concluded that the cost-effective field methodology developed in this paper expects to strike a balance between exposure error and limited data locations. These findings will have important implications in future monitoring design of vertical TRAP exposure to support health studies.

Integrating travel behavior with land use regression to estimate dynamic air pollution exposure in Hong Kong.

BACKGROUND: Epidemiological studies typically use subjects' residential address to estimate individuals' air pollution exposure. However, in reality this exposure is rarely static as people move from home to work/study locations and commute during the day. Integrating mobility and time-activity data may reduce errors and biases, thereby improving estimates of health risks. OBJECTIVES: To incorporate land use regression with movement and building infiltration data to estimate time-weighted air pollution exposures stratified by age, sex, and employment status for population subgroups in Hong Kong. METHODS: A large population-representative survey (N = 89,385) was used to characterize travel behavior, and derive time-activity pattern for each subject. Infiltration factors calculated from indoor/outdoor monitoring campaigns were used to estimate micro-environmental concentrations. We evaluated dynamic and static (residential location-only) exposures in a staged modeling approach to quantify effects of each component. RESULTS: Higher levels of exposures were found for working adults and students due to increased mobility. Compared to subjects aged 65 or older, exposures to PM2.5, BC, and NO2 were 13%, 39% and 14% higher, respectively for subjects aged below 18, and 3%, 18% and 11% higher, respectively for working adults. Exposures of females were approximately 4% lower than those of males. Dynamic exposures were around 20% lower than ambient exposures at residential addresses. CONCLUSIONS: The incorporation of infiltration and mobility increased heterogeneity in population exposure and allowed identification of highly exposed groups. The use of ambient concentrations may lead to exposure misclassification which introduces bias, resulting in lower effect estimates than 'true' exposures.

Land use regression modelling of air pollution in high density high rise cities: A case study in Hong Kong.

Land use regression (LUR) is a common method of predicting spatial variability of air pollution to estimate exposure. Nitrogen dioxide (NO2), nitric oxide (NO), fine particulate matter (PM2.5), and black carbon (BC) concentrations were measured during two sampling campaigns (April-May and November-January) in Hong Kong (a prototypical high-density high-rise city). Along with 365 potential geospatial predictor variables, these concentrations were used to build two-dimensional land use regression (LUR) models for the territory. Summary statistics for combined measurements over both campaigns were: a) NO2 (Mean=106µg/m3, SD=38.5, N=95), b) NO (M=147µg/m3, SD=88.9, N=40), c) PM2.5 (M=35µg/m3, SD=6.3, N=64), and BC (M=10.6µg/m3, SD=5.3, N=76). Final LUR models had the following statistics: a) NO2 (R2=0.46, RMSE=28µg/m3) b) NO (R2=0.50, RMSE=62µg/m3), c) PM2.5 (R2=0.59; RMSE=4µg/m3), and d) BC (R2=0.50, RMSE=4µg/m3). Traditional LUR predictors such as road length, car park density, and land use types were included in most models. The NO2 prediction surface values were highest in Kowloon and the northern region of Hong Kong Island (downtown Hong Kong). NO showed a similar pattern in the built-up region. Both PM2.5 and BC predictions exhibited a northwest-southeast gradient, with higher concentrations in the north (close to mainland China). For BC, the port was also an area of elevated predicted concentrations. The results matched with existing literature on spatial variation in concentrations of air pollutants and in relation to important emission sources in Hong Kong. The success of these models suggests LUR is appropriate in high-density, high-rise cities.

Predictors of intervention adherence among young people living with HIV.

OBJECTIVE: To examine adherence to a 23-session intervention for young people living with HIV. METHODS: Two hundred eight HIV-positive youth were assigned by small cohort to a behavioral intervention. RESULTS: Youth with more personal strengths were more likely to attend the intervention; those with more competing environmental demands (eg, employment, school) were less likely to attend the intervention. Using a social support, spiritual hope, or self-destructive and escape coping style was associated with attendance. Youth who reported many sexual partners attended fewer sessions. Adherence varied by cohort assignment. CONCLUSION: When designing future interventions, high attendance should be considered as a goal.

Intensive versus modified conventional control of blood glucose level in medical intensive care patients: a pilot study.

BACKGROUND: Critically ill postsurgical patients fare better with intensive control of blood glucose level. The link between glucose control and outcome is less well studied for medical intensive care patients. Whether intensive glucose control requires additional staffing is unclear. OBJECTIVES: To compare intensive glucose control with modified conventional control in the medical intensive care unit and to assess compliance with glucose targets, incidence of hypoglycemia, and staffing adequacy. METHODS: Medical intensive care patients who had been receiving mechanical ventilation for less than 24 hours were randomized to intensive or modified conventional protocols for glucose control. Nurses were trained before participating in the study and were interviewed after its completion. RESULTS: Five subjects were randomized to each protocol. Mean blood glucose levels were 5.8 (SD 1.5) mmol/L (105.3 [SD 26.3] mg/dL) for the intensive group and 9.8 (SD 2.5) mmol/L (177.4 [SD 45.5] mg/dL) for the modified conventional group (P < .001). Fifty percent of glucose levels met target values in the intensive group, and 72% of glucose levels met target values in the modified conventional group (P < .001). Severe hypoglycemia (glucose <2.2 mmol/L [<40 mg/dL]) occurred rarely and without complication. Nurses suggested protocols might be improved by using smaller steps in adjusting insulin dosage and reported that simultaneously caring for more than 1 study subject was taxing. CONCLUSIONS: Target levels for blood glucose were achieved with both protocols. Severe hypoglycemia was rare and uncomplicated regardless of type of glucose control. Additional staffing may be needed for intensive glucose control.

HIV-related stigma among market workers in China.

HIV-related stigma was examined among 209 employees and owners of stalls in 5 markets in an eastern coastal city in China. Of the participants 53% were women and 47% were men; 100% were Han. Ages ranged from 18 to 49 years (M=35, SD=8.1). Half of the participants believed that punishment was an appropriate response toward those living with HIV (50%). Over half (56%) were unwilling to be friends with infected individuals. The majority thought that those living with HIV should be isolated (73%). They agreed that persons living with HIV should not take care of other people's children (85%). Punishing beliefs toward persons living with HIV were related to being male, older, married, less educated, and unwilling to be tested for HIV.

Cost-effectiveness of a behavioral intervention for seropositive youth.

An intervention for young people living with HIV (YPLH) was effective in reducing the number of partners of unknown serostatus and the number of unprotected sexual risk acts. In this article, we outline new methods to assess the cost-effectiveness of this intervention. Over a period of 3 months, the intervention would avert an estimated 2.02 new infections per 1,000 YPLH. The cost of mounting the intervention was estimated at US 522 dollars/YPLH, with the cost-effectiveness over a 1-year period being US 103,366 dollars/infection averted. Based on standardized estimates of the cost of treating HIV-positive persons and the adjusted quality of life years lost (10.23 for partners of a mean age of 29 years), the cost utility estimate shows that the treatment costs averted exceed the cost of the intervention. Both the methodology of calculating cost-effectiveness and the cost utility of interventions are important for focusing policy makers, clinicians, community providers, and researchers on prevention for persons living with HIV.

Prevention for substance-using HIV-positive young people: telephone and in-person delivery.

SUMMARY: HIV risky behaviors and health practices were examined among young people living with HIV (YPLH) in Los Angeles, San Francisco, and New York over 15 months in response to receiving a preventive intervention. YPLH aged 16 to 29 years (n = 175; 26% black and 42% Latino; 69% gay men) were randomly assigned to a 3-module intervention totaling 18 sessions delivered by telephone, in person, or a delayed-intervention condition. Intention-to-treat analyses found that the in-person intervention resulted in a significantly higher proportion of sexual acts protected by condoms overall and with HIV-seronegative partners. Pre- and postanalyses of YPLH in the delayed-intervention condition alone found that YPLH tended to have fewer sexual partners, used fewer drugs, reported less emotional distress, and decreased their use of antiretroviral therapies. Prevention programs can be delivered in alternative formats while retaining efficacy. When YPLH are using hard drugs, drug treatment may be needed before delivery of preventive interventions.

Six-year intervention outcomes for adolescent children of parents with the human immunodeficiency virus.

HYPOTHESIS: Having a parent with the human immunodeficiency virus has a significant negative impact on an adolescent child's adjustment. OBJECTIVE: To assess the adjustment of adolescent children to having a parent with the human immunodeficiency virus over 6 years, following the delivery of a coping skills intervention. DESIGN: A randomized controlled trial with repeated evaluations that was analyzed with an intention-to-treat analysis. A skill-based intervention was delivered in 3 modules over 24 sessions, with the third module being delivered only if parents died. SETTING AND PATIENTS: A representative sample of parents with the human immunodeficiency virus (n = 307) and their adolescent children (n = 423) was recruited from the Division of AIDS Services in New York City; 51.5% (n = 158) of the parents died. MAIN OUTCOME MEASURES: Employment and school enrollment, receiving public welfare support, early parenthood, mental health symptoms, and the quality of romantic relationships. RESULTS: Over 6 years, significantly more adolescents in the intervention condition than the control condition were employed or in school (82.58% vs 68.94%), were less likely to receive public welfare payments (25.66% vs 36.65%), were less likely to have psychosomatic symptoms (mean, 0.24 vs 0.31), were more likely to report better problem-solving and conflict resolution skills in their romantic relationships (mean score, 4.38 vs 4.20), expected to have a partner with a good job (mean, 4.57 vs 4.19), and expected to be married when parenting (mean, 3.05 vs 2.40). With marginal significance, the percentage of parents in the intervention condition (34.6%) was less than in the control condition (44.1%). CONCLUSION: Physicians must consider the psychosocial consequences of illness-related challenges on children and provide interventions.

Sexually transmitted disease prevalence and characteristics of market vendors in eastern China.

BACKGROUND AND OBJECTIVES: Sexually transmitted diseases (STDs) have soared in China. To address the impact, we studied market stall vendors in eastern China. GOAL: The goal was to determine STD prevalence and predictors. STUDY DESIGN: A total of 1536 randomly selected market stall vendors were interviewed and tested for STDs. RESULTS: The prevalence of any STD was 20.1% among those reporting sexual intercourse and 5.5% among those reporting never having sexual intercourse. Among those reporting sexual intercourse, chlamydia was most common (9.4%), followed by herpes (9.3%). A total of 4.5% of those reporting never having sexual intercourse had herpes infection, but none had chlamydia. Prevalence of all STDs was higher among females, and those with low education and multiple partners. The pharmacy was the major source of health care (48.8%). CONCLUSION: Generalizing from the results, targeting only STD clinic patients and persons reporting multiple partners for intervention will exclude a high proportion of those with STDs. More effective, less stigmatized sources of STD treatment should be developed.

Reductions in HIV risk among runaway youth.

Runaway youth are 6-12 times more likely to become infected with HIV than other youth. Using a quasi-experimental design, the efficacy of an HIV prevention program was evaluated over 2 years among 2 groups of runaways: (1) those at 2 shelters who received Street Smart, an intensive HIV intervention program, and (2) youth at 2 control shelters. Street Smart provided youth with access to health care and condoms and delivered a 10-session skill-focused prevention program based on social learning theory to youth. Prior to analysis of the intervention's outcomes, propensity scores were used to identify comparable subgroups of youth in the intervention (n = 101) and control conditions (n = 86). Compared to females in the control condition, females in the intervention condition significantly reduced their unprotected sexual acts at 2 years and alcohol use, marijuana use, and the number of drugs used over 12 months. Male adolescents in the intervention condition showed significant reductions in marijuana use over 6 months compared to control youth. Adolescent HIV prevention programs must proactively identify mechanisms for maintaining behavior change over the long-term, and innovative research designs are needed to allow examination of agency-level interventions.

Four-year behavioral outcomes of an intervention for parents living with HIV and their adolescent children.

OBJECTIVE: The adjustment of parents living with HIV (PLH) and their adolescent children was examined over 4 years in response to an intervention. Outcomes at 2 years had been previously published. METHODS: A randomized controlled trial was conducted, with a representative sample from New York City. RESULTS: In the intervention condition, fewer adolescents became teenage parents, and conduct problems tended to be lower over 4 years than in the standard care condition. Fewer parents were drug dependent and tended to relapse into substance use or use passive coping styles compared with the standard care condition over 4 years. The time-trend analysis showed that the significant reductions in problem behaviors and emotional distress previously observed over 15-24 months in the intervention condition, then eroded over time and were non-significant at 48 months. CONCLUSIONS: Ongoing support and skills are needed to maintain intervention effects over longer periods.

Parents' disclosure of HIV to their children.

OBJECTIVE: Parents' disclosure of their HIV serostatus to all of their children is described over time and the impact of disclosure is examined for their adolescent children. DESIGN A representative cohort of parents living with HIV (n = 301) and their adolescent children (n = 395) was recruited and assessed repeatedly over 5 years. METHODS: Disclosures by parents living with HIV of their HIV status to their children were examined in three ways: (i) trends in disclosure over 5 years to all children; (ii) factors associated with parental disclosure; and (iii) the impact of disclosure on adolescent children (not younger children). RESULTS: Parents were more likely to disclose to older (75%) than to younger children (40%). Mothers were more likely to disclose earlier than fathers and they disclosed more often to their daughters than to their sons. Parents were more likely to disclose over time to children of all ages; disclosure did not vary according to parents' ethnicity, socio-economic status, self-esteem, or mental health symptoms. Disclosure was significantly more common among parents with poor health, more stressful life events, larger social networks, and those who perceived their children experiencing more HIV-related stigma. Over time, poor health status and a self-destructive coping style were associated with higher rates of disclosure. Parental disclosure was significantly associated with more problem behaviors and negative family life events among their adolescent children. CONCLUSION: Parental disclosure of HIV status is similar to disclosures by parents with other illnesses. Clinicians must assist patients to make individual decisions regarding disclosure.

Toxicidade ocular experimental do Perfluorotribulitalimine / Experimental ocular toxicity of perfluorotributylamine

Perfluorotributilamine (PFTA) é um importante adjunto na cirurgia vítrea. Alteraçöes do eletrorretinograma em coelhos tem sido reportadas após PFTA ser deixado na cavidade vítrea por duas a quatro semanas. Neste estudo nós nos propusemos a determinar se estas alteraçöes säo reversíveis após a remoçäo do mesmo. Dezessete coelhos submeteram-se á vitrectomia e PFTA foi injetado em 13 olhos. Em oito olhos o PFTA foi removido após 12 dias (Grupo I), em 5 olhos PFTA foi mantido intra-ocular até o dia da enucleaçäo, que ocorreu 35 dias após a injeçäo (Grupo 2) e 4 olhos submeteram-se á cirurgia sem utilizaçäo de PFTA (Grupo 3). Nenhuma alteraçäo clínica foi observada por oftalmoscopia indireta em nenhum coelho. Eletrorretinograma foi resgitrado em 12 coelhos antes da cirurgia (dia 0) e nos dias 9, 19, 25 e 35. Nós observamos uma diminuiçäo da amplitude da onda B na estimulaçäo escotópica 8x e 16x em todos os grupos, sendo mais severa no grupo 2. A remoçäo do PFTA resulta em recuperaçäo da amplitude da onda b para valores próximos do valor pré-operatório.

Artritis reumatoidea precoz / Early rheumatoid arthritis

El diagnostico de artritis reumatoidea precoz se basa generalmente en la anamnesis y el examen fisico y suele establecerse por exclusion. El diagnostico diferencial puede plantear dificultades debido a las grandes variaciones en cuanto edad, sexo, sintomas sistemicos, hallazgos del examen fisico y distribucion de la artropatia. La terapia intensiva inicial debe incluir educacion del paciente, reposo, ejercicios graduados, consejeria y tratamiento farmacologico apropiado. La ausencia de nodulos subcutaneos y de erosion articular puede significar un mejor pronostico en la artritis reumatoidea. La presencia de factor reumatoide, eosinofilia, trombocitosis o vasculitis indica una evolucion menos favorable