348 research outputs found

    Particulate matter concentrations in residences: an intervention study evaluating stand‐alone filters and air conditioners

    Full text link
    This study, a randomized controlled trial, evaluated the effectiveness of free‐standing air filters and window air conditioners (ACs) in 126 low‐income households of children with asthma. Households were randomized into a control group, a group receiving a free‐standing HEPA filter placed in the child’s sleeping area, and a group receiving the filter and a window‐mounted AC. Indoor air quality (IAQ) was monitored for week‐long periods over three to four seasons. High concentrations of particulate matter (PM) and carbon dioxide were frequently seen. When IAQ was monitored, filters reduced PM levels in the child’s bedroom by an average of 50%. Filter use varied greatly among households and declined over time, for example, during weeks when pollutants were monitored, filter use was initially high, averaging 84 ± 27%, but dropped to 63 ± 33% in subsequent seasons. In months when households were not visited, use averaged only 34 ± 30%. Filter effectiveness did not vary in homes with central or room ACs. The study shows that measurements over multiple seasons are needed to characterize air quality and filter performance. The effectiveness of interventions using free‐standing air filters depends on occupant behavior, and strategies to ensure filter use should be an integral part of interventions. Practical Implications Environmental tobacco smoke (ETS) increased particulate matter (PM) levels by about 14 μg/m 3 and was often detected using ETS‐specific tracers despite restrictions on smoking in the house as reported on questionnaires administered to caregivers. PM concentrations depended on season, filter usage, relative humidity, air exchange ratios, number of children, outdoor PM levels, sweeping/dusting, and presence of a central air conditioner (AC). Free‐standing air filters can be an effective intervention that provides substantial reductions in PM concentrations if the filters are used. However, filter use was variable across the study population and declined over the study duration, and thus strategies are needed to encourage and maintain use of filters. The variability in filter use suggests that exposure misclassification is a potential problem in intervention studies using filters. The installation of a room AC in the bedroom, intended to limit air exchange ratios, along with an air filter, did not lower PM levels more than the filter alone.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91183/1/j.1600-0668.2011.00761.x.pd

    Accepted: 2011-10-04.) © SAJEI South Afr

    Get PDF
    Original Research: GGSTM1, GSTP1 and NQO1 polymorphisms and susceptibility to asthma among South African children Gluthathione-S-transferase (GSTM1 and GSTP1) and nicotinamide quinone oxidoreductase (NQO1) genes play an important role in cellular protection against oxidative stress, which has been linked to asthma pathogenesis. We investigated whether common, functional polymorphisms in GSTM1, GSTP1, and NQO1 influence susceptibility to asthma among schoolchildren in South Africa. Genomic deoxyribonucleic acid (DNA) was extracted from 317 primary schoolchildren, aged 9-11 years, from the urban, underprivileged socio-economic communities of Durban. GSTM1 (null vs. present genotype), GSTP1 (Ile105Val; AA →AG+GG) and the NQO1 (Pro/Ser; CC →CT/TT) genotypes were determined using polymerase chain reaction. Among the children, 30% were GSTM1 null, 65% carried the G allele for GSTP1, and 36% carried the C allele for NQO1.There was a high prevalence of asthma of any severity (46.1%), with 20.4% reporting persistent asthma. The GSTP1 AG+GG polymorphic genotype was significantly associated with persistent asthma (adjusted OR = 3.98; CI = 1.39, 11.36, p-value = 0.01). Neither the GSTM1, nor the NQO1, genotype was a significant predictor of persistent asthma. Therefore, the GSTP1 A/G variant may modulate the risk of persistent asthma among our sample

    Differences in health care use and outcomes by the timing of in-hospital worsening heart failure

    Get PDF
    BACKGROUND: Patients hospitalized with acute heart failure may experience worsening symptoms requiring escalation of therapy. In-hospital worsening heart failure is associated with worse in-hospital and postdischarge outcomes, but associations between the timing of worsening heart failure and outcomes are unknown. METHODS: Using data from a large clinical registry linked to Medicare claims, we examined characteristics, outcomes, and costs of patients hospitalized for acute heart failure. We defined in-hospital worsening heart failure by the use of inotropes or intravenous vasodilators or initiation of mechanical circulatory support, hemodialysis, or ventilation. The study groups were early worsening heart failure (n = 1,990), late worsening heart failure (n = 4,223), complicated presentation (n = 15,361), and uncomplicated hospital course (n = 41,334). RESULTS: Among 62,908 patients, those with late in-hospital worsening heart failure had higher in-hospital and postdischarge mortality than patients with early worsening heart failure or complicated presentation. Those with early or late worsening heart failure had more frequent all-cause and heart failure readmissions at 30 days and 1 year, with resultant higher costs, compared with patients with an uncomplicated hospital course. CONCLUSION: Although late worsening heart failure was associated with the highest mortality, both early and late worsening heart failures were associated with more frequent readmissions and higher health care costs compared to uncomplicated hospital course. Prevention of worsening heart failure may be an important focus in the care of hospitalized patients with acute heart failure

    Hemodynamic Predictors of Heart Failure Morbidity and Mortality: Fluid or Flow?

    Get PDF
    BACKGROUND: Patients with advanced heart failure may persist for prolonged times with persistent hemodynamic abnormalities; intermediate and long-term outcomes of these patients are unknown. METHODS AND RESULTS: We used ESCAPE trial data to examine characteristics and outcomes of patients with invasive hemodynamic monitoring during an acute heart failure hospitalization. Patients were stratified by final measurement of cardiac index (CI; L/min/m2) and pulmonary capillary wedge pressure (PCWP; mmHg) before catheter removal. The study groups were CI ≥ 2/PCWP <20 (n = 74), CI ≥ 2/PCWP ≥ 20 (n = 37), CI < 2/PCWP < 20 (n = 23), and CI < 2/PCWP ≥ 20 (n = 17). Final CI was not associated with the combined risk of death, cardiovascular hospitalization, and transplantation (HR:1.03, 95% CI:0.96–1.11 per 0.2 L/min/m(2) decrease, p=0.39), but final PCWP ≥ 20mmHg was associated with increased risk of these events (HR:2.03, 95% CI:1.31–3.15, p<0.01), as was higher final right atrial pressure (RAP; HR:1.09, 95% CI:1.06–1.12 per mmHg increase, p<0.01). CONCLUSION: Final PCWP and final RAP were stronger predictors of post-discharge outcomes than CI in patients with advanced heart failure. The ability to lower filling pressures appears to be more prognostically important than improving CI in the management of patients with advanced heart failure. CLINICALTRIALS.GOV IDENTIFIER: NCT0000061

    Do neighborhood economic characteristics, racial composition, and residential stability predict perceptions of stress associated with the physical and social environment?

    Full text link
    http://deepblue.lib.umich.edu/bitstream/2027.42/61291/1/schulz aj, zenk s, israel ba, mentz g, stokes c, galea s, do neighborhood economic characteristics, racial composition, and residential stability predict perceptions.pd

    Air Pollution–Associated Changes in Lung Function among Asthmatic Children in Detroit

    Get PDF
    In a longitudinal cohort study of primary-school–age children with asthma in Detroit, Michigan, we examined relationships between lung function and ambient levels of particulate matter ≤ 10 μm and ≤ 2.5 μm in diameter (PM(10) and PM(2.5)) and ozone at varying lag intervals using generalized estimating equations. Models considered effect modification by maintenance corticosteroid (CS) use and by the presence of an upper respiratory infection (URI) as recorded in a daily diary among 86 children who participated in six 2-week seasonal assessments from winter 2001 through spring 2002. Participants were predominantly African American from families with low income, and > 75% were categorized as having persistent asthma. In both single-pollutant and two-pollutant models, many regressions demonstrated associations between higher exposure to ambient pollutants and poorer lung function (increased diurnal variability and decreased lowest daily values for forced expiratory volume in 1 sec) among children using CSs but not among those not using CSs, and among children reporting URI symptoms but not among those who did not report URIs. Our findings suggest that levels of air pollutants in Detroit, which are above the current National Ambient Air Quality Standards, adversely affect lung function of susceptible asthmatic children

    Avaliação da fertilidade do solo em sistemas de rotação de culturas de 1993 a 2005.

    Get PDF
    bitstream/item/128665/1/ID2841-LVdocumentos86-p140-154.pd

    The Additive Prognostic Value of Serial Plasma Interleukin-6 Levels over Changes in Brain Natriuretic Peptide in Patients with Acute Heart Failure

    Get PDF
    Background: Elevated plasma interleukin-6 (IL-6) concentrations are frequently observed in patients with acute heart failure (AHF). However, the predictive value of serial IL-6 measurements beyond brain natriuretic peptide (BNP) remains poorly characterized. Methods and Results: This was a retrospective analysis of the PROTECT cohort (2033 patients with AHF). Plasma IL-6 and BNP levels were determined on days 1, 2, 7 and 14 after admission for AHF in 1591 (78.3%), 1462 (71.9%), 1445 (71.1%) and 1451 (71.4%) patients, respectively. The primary endpoint was 180-day all-cause mortality. The median day-1 IL-6 concentration was 11.1 pg/mL (IQR: 6.6, 20.9) and decreased to 10.1 pg/mL (IQR: 5.6-18.5) at day-7. Higher cross-sectional IL-6 concentrations at all time-points predicted the primary endpoint, independent of a risk model for this cohort and changes in BNP. Each doubling of IL-6 between day-1 and day-7 predicted the primary endpoint independent of baseline IL-6 concentrations, the risk model, baseline BNP and changes in BNP [HR (95% CI): 1.18 (1.07-1.30), p=0.0013]. Collectively, 214 (17%) patients experienced at least a doubling of their IL-6 concentrations between day-1 and day-7. Conclusions: We demonstrate that the temporal evolution patterns of IL-6 in patients with AHF have additive prognostic value independent of changes in BNP

    Influence of viral infection on the relationships between airway cytokines and lung function in asthmatic children

    Full text link
    Abstract Background Few longitudinal studies examine inflammation and lung function in asthma. We sought to determine the cytokines that reduce airflow, and the influence of respiratory viral infections on these relationships. Methods Children underwent home collections of nasal lavage during scheduled surveillance periods and self-reported respiratory illnesses. We studied 53 children for one year, analyzing 392 surveillance samples and 203 samples from 85 respiratory illnesses. Generalized estimated equations were used to evaluate associations between nasal lavage biomarkers (7 mRNAs, 10 proteins), lung function and viral infection. Results As anticipated, viral infection was associated with increased cytokines and reduced FVC and FEV1. However, we found frequent and strong interactions between biomarkers and virus on lung function. For example, in the absence of viral infection, CXCL10 mRNA, MDA5 mRNA, CXCL10, IL-4, IL-13, CCL4, CCL5, CCL20 and CCL24 were negatively associated with FVC. In contrast, during infection, the opposite relationship was frequently found, with IL-4, IL-13, CCL5, CCL20 and CCL24 levels associated with less severe reductions in both FVC and FEV1. Conclusions In asthmatic children, airflow obstruction is driven by specific pro-inflammatory cytokines. In the absence of viral infection, higher cytokine levels are associated with decreasing lung function. However, with infection, there is a reversal in this relationship, with cytokine abundance associated with reduced lung function decline. While nasal samples may not reflect lower airway responses, these data suggest that some aspects of the inflammatory response may be protective against viral infection. This study may have ramifications for the treatment of viral-induced asthma exacerbations.https://deepblue.lib.umich.edu/bitstream/2027.42/146519/1/12931_2018_Article_922.pd

    Private trade and monopoly structures : the East India Companies and the commodity trade to Europe in the eighteenth century

    Get PDF
    Our research is about the trade in material goods from Asia to Europe over this period, and its impact on Europe’s consumer and industrial cultures. It entails a comparative study of Europe’s East India Companies and the private trade from Asia over the period. The commodities trade was heavily dependent on private trade. The historiography to date has left a blind spot in this area, concentrating instead on corruption and malfeasance. Taking a global history approach we investigate the trade in specific consumer goods in many qualities and varieties that linked merchant communities and stimulated information flows. We set out how private trade functioned alongside and in connection with the various European East India companies; we investigate how this changed over time, how it drew on the Company infrastructure, and how it took the risks and developed new and niche markets for specific Asian commodities that the Companies could not sustain
    corecore