70 research outputs found

    Gaseous Air Pollutants and Hospitalization for Respiratory Disease in the Neonatal Period

    Get PDF
    OBJECTIVE: Current levels of ambient air pollution are associated with morbidity and mortality in the general population. To determine the influence of gaseous air pollutants on neonatal respiratory morbidity, we tested the association between daily respiratory hospitalizations and daily concentrations of ambient air pollution gases: ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide, in 11 large Canadian cities. STUDY DESIGN: Daily time-series analyses were employed and results were adjusted for day of the week, temperature, barometric pressure, and relative humidity. RESULTS: The percent increases in hospitalization associated with an increase in air pollution equivalent to its interquartile range were 3.35 [95% confidence interval (CI), 1.73–4.77] for O(3), 2.85 (95% CI, 1.68–4.02) for NO(2), 1.66 (95% CI, 0.63–2.69) for SO(2), and 1.75 (95% CI, 0.48–3.02) for CO. The independent effect of all pollutants combined was 9.61% (95% CI, 4.52–14.7%). CONCLUSION: Our results suggest that neonates are experiencing adverse effects of air pollution at current levels in Canada, and that accounts for a significant proportion of hospitalizations in this subgroup

    Air Pollution and Mortality in Chile: Susceptibility among the Elderly

    Get PDF
    OBJECTIVE: The estimated mortality rate associated with ambient air pollution based on general population studies may not be representative of the effects on certain subgroups. The objective of the present study was to determine the influence of relatively high concentrations of air pollution on mortality in a general population sample and in the very elderly. STUDY DESIGN: Daily time-series analyses tested the association between daily air pollution and daily mortality in seven Chilean urban centers during 1997–2003. Results were adjusted for day of the week and humidex. RESULTS: Daily averaged particulate matter with aerodynamic matter < 10 μm (PM(10)) was 84.88 μg/m(3), sulfur dioxide was 14.08ppb, and carbon monoxide was 1.29 ppb. The 1-hr maximum ozone was 100.13 ppb. The percentage increases in nonaccidental mortality associated with an increase in PM(10) equivalent to its mean were 4.53 (t-ratio 1.52) for those < 65 years and 14.03 (3.87) for those > 85 years. Respective values were 4.96 (1.17) and 8.56 (2.02) for O(3); 4.77 (2.50) and 7.92 (3.23) for SO(2); and 4.10 (2.52) and 8.58 (4.45) for CO. CONCLUSION: Our results suggest that the very elderly are particularly susceptible to dying from air pollution. Concentrations deemed acceptable for the general population may not adequately protect the very elderly

    Association of the Frequency of Respiratory Illness in Early Childhood with a Change in the Distribution of Blood Lymphocyte Subpopulations

    Get PDF
    Little is known about the distribution of lymphocyte phenotypes in young children and the association specific phenotypes may have with respiratory illnesses. The objective of this study was to describe lymphocyte distributions in children at approximately 2 years of age and to test for associations with the frequency of respiratory illness during the first 2 years of life. We hypothesized that an increased frequency of illness would be associated with those phenotypes that reflect previous antigen exposure and/or immune activation. Seventy-three children were followed during their first 2 years of life with daily symptom diaries and twice-monthly telephone calls to ascertain the incidence of respiratory illness. After the children reached 2 years of age, the phenotypes of circulating blood lymphocytes were measured by flow cytometry. Associations between illness and phenotypes were adjusted for education level of parents; hours per week in day care; hours per week exposed to environmental tobacco smoke, mould, or water damage in bedroom; and parental history of allergy and asthma. The resulting median lymphocyte count was 4.0 × 109 per litre (standard deviation, 1.3) with a CD4/CD8 count of 2.28, consistent with published values. Illness rates were positively associated with the percentage of CD8+ CD38+ T cells (unadjusted p = .03, adjusted p = .014), CD8+ CD45RO+ T cells (unadjusted p = .06, adjusted p = .036), and CD4+ CD45RO+ T cells (unadjusted p = .01, adjusted p = .005). Our conclusions is that there is an association between the distribution of lymphocyte phenotypes and the incidence of respiratory illness early in life. Future research is recommended to determine the directionality of this association

    Effects of air pollution and the introduction of the London Low Emission Zone on the prevalence of respiratory and allergic symptoms in schoolchildren in East London: a sequential cross-sectional study

    Get PDF
    The adverse effects of traffic-related air pollution on children’s respiratory health have been widely reported, but few studies have evaluated the impact of traffic-control policies designed to reduce urban air pollution. We assessed associations between traffic-related air pollutants and respiratory/allergic symptoms amongst 8–9 year-old schoolchildren living within the London Low Emission Zone (LEZ). Information on respiratory/allergic symptoms was obtained using a parent-completed questionnaire and linked to modelled annual air pollutant concentrations based on the residential address of each child, using a multivariable mixed effects logistic regression analysis. Exposure to traffic-related air pollutants was associated with current rhinitis: NOx (OR 1.01, 95% CI 1.00–1.02), NO2 (1.03, 1.00–1.06), PM10 (1.16, 1.04–1.28) and PM2.5 (1.38, 1.08–1.78), all per μg/m3 of pollutant, but not with other respiratory/allergic symptoms. The LEZ did not reduce ambient air pollution levels, or affect the prevalence of respiratory/allergic symptoms over the period studied. These data confirm the previous association between traffic-related air pollutant exposures and symptoms of current rhinitis. Importantly, the London LEZ has not significantly improved air quality within the city, or the respiratory health of the resident population in its first three years of operation. This highlights the need for more robust measures to reduce traffic emissions

    Outcomes of Patients with Nelson's Syndrome after Primary Treatment: A Multicenter Study from 13 UK Pituitary Centers.

    Get PDF
    CONTEXT: Long-term outcomes of patients with Nelson's syndrome (NS) have been poorly explored, especially in the modern era. OBJECTIVE: To elucidate tumor control rates, effectiveness of various treatments, and markers of prognostic relevance in patients with NS. PATIENTS, DESIGN, AND SETTING: Retrospective cohort study of 68 patients from 13 UK pituitary centers with median imaging follow-up of 13 years (range 1-45) since NS diagnosis. RESULTS: Management of Cushing's disease (CD) prior to NS diagnosis included surgery+adrenalectomy (n = 30; eight patients had 2 and one had 3 pituitary operations), surgery+radiotherapy+adrenalectomy (n = 17; two received >1 courses of irradiation, two had ≥2 pituitary surgeries), radiotherapy+adrenalectomy (n = 2), and adrenalectomy (n = 19). Primary management of NS mainly included surgery, radiotherapy, surgery+radiotherapy, and observation; 10-year tumor progression-free survival was 62% (surgery 80%, radiotherapy 52%, surgery+radiotherapy 81%, observation 51%). Sex, age at CD or NS diagnosis, size of adenoma (micro-/macroadenoma) at CD diagnosis, presence of pituitary tumor on imaging prior adrenalectomy, and mode of NS primary management were not predictors of tumor progression. Mode of management of CD before NS diagnosis was a significant factor predicting progression, with the group treated by surgery+radiotherapy+adrenalectomy for their CD showing the highest risk (hazard ratio 4.6; 95% confidence interval, 1.6-13.5). During follow-up, 3% of patients had malignant transformation with spinal metastases and 4% died of aggressively enlarging tumor. CONCLUSIONS: At 10 years follow-up, 38% of the patients diagnosed with NS showed progression of their corticotroph tumor. Complexity of treatments for the CD prior to NS diagnosis, possibly reflecting corticotroph adenoma aggressiveness, predicts long-term tumor prognosis

    The expression of the ubiquitin ligase SIAH2 (seven in absentia homolog 2) is mediated through gene copy number in breast cancer and is associated with a basal-like phenotype and p53 expression

    Get PDF
    Introduction: The seven in absentia homolog 2 (SIAH2) protein plays a significant role in the hypoxic response by regulating the abundance of hypoxia-inducible factor-α; however, its role in breast carcinoma is unclear. We investigated the frequency and expression pattern of SIAH2 in two independent cohorts of sporadic breast cancers.Methods: Immunohistochemical evaluation of SIAH2protein expression was conducted in normal breast tissues and in tissue microarrays comprising ductal carcinoma in situ (DCIS) and a cohort of invasive breast carcinomas. Correlation analysis was performed between SIAH2 and clinicopathological variables and intrinsic breast cancer subgroups and validated in a cohort of 293 invasive ductal carcinomas. Promoter methylation, gene copy number and mRNA expression of SIAH2 were determined in a panel of basal-like tumors and cell lines.Results: There was a significant increase in nuclear SIAH2 expression from normal breast tissues through to DCIS and progression to invasive cancers. A significant inverse correlation was apparent between SIAH2 and estrogen receptor and progesterone receptor and a positive association with tumor grade, HER2, p53 and an intrinsic basal-like subtype. Logistic regression analysis confirmed the significant positive association between SIAH2 expression and the basal-like phenotype. No SIAH2 promoter methylation was identified, yet there was a significant correlation between SIAH2 mRNA and gene copy number. SIAH2-positive tumors were associated with a shorter relapse-free survival in univariate but not multivariate analysis.Conclusions: SIAH2 expression is upregulated in basal-like breast cancers via copy number changes and/or transcriptional activation by p53 and is likely to be partly responsible for the enhanced hypoxic drive through abrogation of the prolyl hydroxylases

    Long acting β(2 )agonists for stable chronic obstructive pulmonary disease with poor reversibility: a systematic review of randomised controlled trials

    Get PDF
    BACKGROUND: The long acting β2-agonists, salmeterol and formoterol, have been recommended, by some, as first line treatment of stable chronic obstructive pulmonary disease (COPD). We reviewed evidence of efficacy and safety when compared with placebo or anticholinergic agents in patients with poorly reversible COPD. METHODS: After searching MEDLINE, EMBASE, HealthSTAR, BIOSIS Previews, PASCAL, ToxFile, SciSearch, the Cochrane Library, and PubMed, as well as Web sites, selected journals, reference lists, and contacting drug manufacturers, two reviewers independently screened reports of randomised controlled trials of parallel or crossover design lasting four weeks or longer and including patients with a forced expiratory volume in one second (FEV1) ≤ 75% of predicted, a ratio of FEV1 to forced vital capacity (FVC) ≤ 88% of predicted, and < 15% improvement from baseline FEV1 after a dose of a β2 agonist. We included trials comparing salmeterol or formoterol with placebo or with ipratropium bromide and reporting one of these outcomes: lung function; exercise capacity; quality of life scores; dyspnea; exacerbations; rescue inhaler use; incidence of tachycardia, hypokalemia, or dry mouth. Two reviewers assessed the quality of included reports using the Jadad scale and allocation concealment, and abstracted data. RESULTS: Twelve trials satisfied our inclusion criteria; eight were high quality (Jadad score >2) and four were low quality (≤ 2). The adequacy of allocation concealment was unclear in all of them. We did not perform a meta-analysis due to differences in trial design and how outcomes were reported. Two trials comparing salmeterol with ipratropium did not detect differences; one trial comparing formoterol and ipratropium described greater improvement with formoterol in morning PEFR (15.3 versus 7.1 l/min, p = 0.040). Of twelve trials comparing long acting β2 agonists with placebo, six reported no improvement in exercise capacity, eleven reported improvements in FEV1 lung function (one reported no improvement), six reported less rescue inhaler usage (one reported no difference) and five reported improved dyspnea scores (two reported no improvement). Differences in quality of life were detected in one salmeterol trial ; however, two salmeterol, and one formoterol trial reported no differences. Adverse effects of interest were not reported. CONCLUSION: In terms of clinical outcomes and safety, we could not find convincing evidence that salmeterol and formoterol have demonstrated advantages to ipratropium, a less expensive drug, for patients with stable COPD and poor reversibility. Compared to placebo, we found evidence of reduced rescue inhaler usage and improved spirometric outcomes without a significant impact on quality of life or exercise capacity

    Distribution and seasonality of rhinovirus and other respiratory viruses in a cross-section of asthmatic children in Trinidad, West Indies

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Childhood asthma in the Caribbean is advancing in prevalence and morbidity. Though viral respiratory tract infections are reported triggers for exacerbations, information on these infections with asthma is sparse in Caribbean territories. We examined the distribution of respiratory viruses and their association with seasons in acute and stable asthmatic children in Trinidad.</p> <p>Methods</p> <p>In a cross-sectional study of 70 wheezing children attending the emergency department for nebulisation and 80 stable control subjects (2 to 16 yr of age) in the asthma clinic, nasal specimens were collected during the dry (<it>n </it>= 38, January to May) and rainy (<it>n </it>= 112, June to December) seasons. A multitarget, sensitive, specific high-throughput Respiratory MultiCode assay tested for respiratory-virus sequences for eight distinct groups: human rhinovirus, respiratory syncytial virus, parainfluenza virus, influenza virus, metapneumovirus, adenovirus, coronavirus, and enterovirus.</p> <p>Results</p> <p>Wheezing children had a higher [χ<sup>2 </sup>= 5.561, <it>p </it>= 0.018] prevalence of respiratory viruses compared with stabilized asthmatics (34.3% (24) versus (vs.) 17.5% (14)). Acute asthmatics were thrice as likely to be infected with a respiratory virus (OR = 2.5, 95% CI = 1.2 – 5.3). The predominant pathogens detected in acute versus stable asthmatics were the rhinovirus (RV) (<it>n </it>= 18, 25.7% vs. <it>n </it>= 7, 8.8%; <it>p </it>= 0.005), respiratory syncytial virus B (RSV B) (<it>n </it>= 2, 2.9% vs. <it>n </it>= 4, 5.0%), and enterovirus (<it>n </it>= 1, 1.4% vs. <it>n </it>= 2, 2.5%). Strong odds for rhinoviral infection were observed among nebulised children compared with stable asthmatics (<it>p </it>= 0.005, OR = 3.6, 95% CI = 1.4 – 9.3,). RV was prevalent throughout the year (Dry, <it>n </it>= 6, 15.8%; Rainy, <it>n </it>= 19, 17.0%) and without seasonal association [χ<sup>2 </sup>= 0.028, <it>p </it>= 0.867]. However it was the most frequently detected virus [Dry = 6/10, (60.0%); Rainy = 19/28, (67.9%)] in both seasons.</p> <p>Conclusion</p> <p>Emergent wheezing illnesses during childhood can be linked to infection with rhinovirus in Trinidad's tropical environment. Viral-induced exacerbations of asthma are independent of seasons in this tropical climate. Further clinical and virology investigations are recommended on the role of infections with the rhinovirus in Caribbean childhood wheeze.</p

    Anti-angiogenic therapy for cancer: Current progress, unresolved questions and future directions

    Get PDF
    Tumours require a vascular supply to grow and can achieve this via the expression of pro-angiogenic growth factors, including members of the vascular endothelial growth factor (VEGF) family of ligands. Since one or more of the VEGF ligand family is overexpressed in most solid cancers, there was great optimism that inhibition of the VEGF pathway would represent an effective anti-angiogenic therapy for most tumour types. Encouragingly, VEGF pathway targeted drugs such as bevacizumab, sunitinib and aflibercept have shown activity in certain settings. However, inhibition of VEGF signalling is not effective in all cancers, prompting the need to further understand how the vasculature can be effectively targeted in tumours. Here we present a succinct review of the progress with VEGF-targeted therapy and the unresolved questions that exist in the field: including its use in different disease stages (metastatic, adjuvant, neoadjuvant), interactions with chemotherapy, duration and scheduling of therapy, potential predictive biomarkers and proposed mechanisms of resistance, including paradoxical effects such as enhanced tumour aggressiveness. In terms of future directions, we discuss the need to delineate further the complexities of tumour vascularisation if we are to develop more effective and personalised anti-angiogenic therapies. © 2014 The Author(s)
    corecore