Mortality from infectious pneumonia in metal workers: a comparison with deaths from asthma in occupations exposed to respiratory sensitizers

Introduction: national analyses of mortality in England and Wales have repeatedly shown excess deaths from pneumonia in welders. During 1979-1990 the excess was attributable largely to deaths from lobar pneumonia and pneumonias other than bronchopneumonia, limited to working-aged men, and apparent in other metal fume-exposed occupations. We assessed findings for 1991-2000 and compared the mortality pattern with that from asthma in occupations exposed to known respiratory sensitizers.Methods: the Office of National Statistics supplied data on deaths by underlying cause among men aged 16-74 years in England and Wales during 1991-2000, including age and last held occupation. We abstracted data on pneumonia for occupations with exposure to metal fume and on asthma for occupations commonly reported to surveillance schemes as at risk of occupational asthma. We estimated expected numbers of deaths by applying age-specific proportions of deaths by cause in the population to the total deaths by age in each occupational group. Observed and expected numbers were compared for each cause of death.Results: among working-aged men in metal fume-exposed occupations we found excesses of mortality from pneumococcal and lobar pneumonia (54 deaths vs. 27.3 expected) and from pneumonias other than bronchopneumonia (71 vs. 52.4), but no excess from these causes at older ages, or from bronchopneumonia at any age. The attributable mortality from metal fume (45.3 excess deaths) compared with an estimated 62.6 deaths from occupational asthma.Conclusion: exposure to metal fume is a material cause of occupational mortality. The hazard deserves far more attention than it presently receive

In-situ repair of composite sandwich structures using cyanoacrylates

A novel method for the in-situ repair of composite sandwich structures using microvascular networks and cyanoacrylate (CA) adhesive systems has been presented. Upon a damage event, the vascules become ruptured, providing a route for the introduction of adhesive directly into the damage site. The efficacy of the two repair agents was first assessed under static and fatigue conditions using a modified double cantilever beam (DCB) method. Once baseline fracture behaviour of the cyanoacrylates has been established, they were further assessed by injection into a series of pre-damaged T-joint specimens. The presence of the vasculature was shown to have no detrimental impact on mechanical performance, whilst both of the cyanoacrylates were shown to be highly effective in the recovery of stiffness and ultimate strength of the T-joint specimens. (C) 2016 Elsevier Ltd. All rights reserved

Occupational Asthma in Antibiotic Manufacturing Workers: Case Reports and Systematic Review

Background. The risks of occupational asthma (OA) from antibiotics are uncertain. We report 4 new cases and a systematic review of the literature. Methods. Cases were identified through a specialist clinic, each underwent specific provocation testing (SPT). We subsequently reviewed the published literature. Results. The patients were employed in the manufacture of antibiotics; penicillins were implicated in three cases, in the fourth erythromycin, not previously reported to cause OA. In two, there was evidence of specific IgE sensitisation. At SPT each developed a late asthmatic reaction and increased bronchial hyperresponsiveness. 36 case reports have been previously published, 26 (citing penicillins or cephalosporins). Seven cross-sectional workplace-based surveys found prevalences of 5–8%. Conclusions. OA in antibiotic manufacturers may be more common than is generally recognised. Its pathogenesis remains unclear; immunological tests are of uncertain value and potential cases require confirmation with SPT. Further study of its frequency, mechanisms, and diagnosis is required

MultiTex RCT - A multifaceted intervention package for protection against cotton dust exposure among textile workers - A cluster randomized controlled trial in Pakistan: Study protocol

Background: In the Pakistani textile industry the prevalence of workplace respiratory illnesses, including byssinosis, is high. The MultiTex RCT study aims to determine the effectiveness of a multifaceted intervention package in reducing dust levels in cotton mills, decreasing the frequency of respiratory symptoms among cotton textile workers, and improving their lung function.Methods/design: We will conduct a cluster-randomized controlled trial at 28 textile mills in Karachi. The intervention will comprise: training in occupational health for all workers and managers reinforced by regular refresher sessions; the formation of workplace committees to draw up, agree and promote a health and safety plan that includes wet mopping, safe disposal of cotton dust, and the use of simple face-masks, as well as further publicity about the risks from cotton dust; and provision of adequate supplies of face-masks to support the health and safety plan. Participating mills will be randomized to intervention and control arms following a baseline survey. The impact of the intervention will be determined through follow-up surveys conducted at 3, 12 and 18 months. Data collection in the surveys will include spirometry, questionnaire-based interviews and cotton-dust measurements.Discussion: If successful, the study may pave the way for simple, low-cost interventions that can help reduce cotton-dust levels in textile mills, and improve the respiratory health of textile workers in developing countries such as Pakistan

A precursor to the relational evaluation procedure: Analyzing stimulus equivalence II

A series of experiments examined the precursor to the relational evaluation procedure (pREP). The pREP is capable of facilitating derived relational responding, but it is less effective than matching-to-sample (MTS) in producing equivalence class formation. Part 1 of the present study tested possible reasons for the inferiority of the. pREP relative to MTS. The first two experiments compared the performances of subjects on two modified versions of the pREP with their performances on a simultaneous MTS procedure. The modifications did not improve performances on the pREP. Experiment 3 compared the pREP with a delayed MTS procedure but again MTS was more effective than the pREP in producing equivalence. Part 2 of the study determined whether pREP equivalence responding could be facilitated by preexposing subjects to a history of MTS training and testing. In Experiment 4, subjects were trained and tested on a MTS procedure until they reliably produced both symmetry and equivalence, and were then exposed to pREP training and testing using the same stimuli, and relations among stimuli, as employed for the MTS procedure. Following this, subjects were exposed to pREP training and testing using novel stimuli. All subjects reliably produced both symmetry and equivalence responding on the pREP with both familiar arid novel stimuli. Experiment 5 determined whether using the same stimulus sets across the two procedures was necessary. Results showed that if symmetry and equivalence were shown on a MTS procedure followed immediately by pREP training and testing using novel stimuli, only 2 out of 4 subjects successfully demonstrated both symmetry and equivalence using the latter procedure

Prenatal Dichlorodiphenyldichloroethylene (DDE) and Asthma in Children

Prevalence of asthma increases with increasing dichlorodiphenyldichloroethylene (DDE) levels. However, the effect of early-life exposure, the fundamental window of exposure, is unknown. We assessed the association between prenatal DDE and other organochlorine compounds, and atopy and asthma during infancy. All women presenting for antenatal care in Menorca (Spain) over 12 months starting in mid-1997 were invited to take part in a longitudinal study; 482 children were subsequently enrolled, and 468 (97.1%) provided complete outcome data up to the fourth year of study. Prenatal exposure of organochlorine compounds was measured in cord serum in 405 (83%) children. Asthma was defined on the basis of wheezing at 4 years of age, persistent wheezing, or doctor-diagnosed asthma. We measured specific immunoglobulin-E (IgE) against house dust mite, cat, and grass in sera extracted at 4 years of age. DDE (median = 1.03 ng/mL) was detected in all children, as well as hexachlorobenzene (0.68 ng/mL) and polychlorobiphenyls (0.69 ng/mL). Wheezing at 4 years of age increased with DDE concentration, particularly at the highest quartile [9% in the lowest quartile (< 0.57 ng/mL) vs. 19% in the highest quartile (1.90 ng/mL); relative risk = 2.63 (95% confidence interval 1.19–4.69), adjusting for maternal asthma, breast-feeding, education, social class, or other organochlorines]. The association was not modified by IgE sensitization and occurred with the same strength among nonatopic subjects and among those with persistent wheezing or diagnosed asthma. DDE was not associated with atopy alone. Prenatal exposure to DDE residues may contribute to development of asthma