Background:Studies from several countries indicate that welders experience increased risk of mortality and morbidity from ischaemic heart disease. Although the underlying mechanisms are unclear, ...vascular responses to particulate matter contained in welding fumes may play a role. To investigate this, we studied the acute effects of welding fume exposure on the endothelial component of vascular function, as measured by circulating adhesion molecules involved in leukocyte adhesion (sICAM-1 and sVCAM-1) and coagulation (vWF).Methods:A panel of 26 male welders was studied repeatedly across a 6 h work-shift on a high exposure welding day and/or a low exposure non-welding day. Personal PM2.5 exposure was measured throughout the work-shift. Blood samples were collected in the morning (baseline) prior to the exposure period, immediately after the exposure period, and the following morning. To account for the repeated measurements, we used linear mixed models to evaluate the effects of welding (binary) and PM2.5 (continuous) exposure on each blood marker, adjusting for baseline blood marker concentration, smoking, age and time of day.Results:Welding and PM2.5 exposure were significantly associated with a decrease in sVCAM-1 in the afternoon and the following morning and an increase in vWF in the afternoon.Conclusions:The data suggest that welding and short-term occupational exposure to PM2.5 may acutely affect the endothelial component of vascular function.
Context The scientific study of yoga requires rigorous methodology. This review aimed to systematically assess all studies of yoga interventions to (1) determine yoga intervention characteristics; ...(2) examine methodologic quality of the subset of RCTs; and (3) explore how well these interventions are reported. Evidence acquisition Searches were conducted through April 2012 in PubMed, PsycINFO, Ageline, and Ovid’s Alternative and Complementary Medicine database using the text term yoga , and through handsearching five journals. Original studies were included if the intervention (1) consisted of at least one yoga session with some type of health assessment; (2) targeted adults aged ≥18 years; (3) was published in an English-language peer-reviewed journal; and (4) was available for review. Evidence synthesis Of 3,062 studies identified, 465 studies in 30 countries were included. Analyses were conducted through 2013. Most interventions took place in India ( n =228) or the U.S. ( n =124), with intensity ranging from a single yoga session up to two sessions per day. Intervention lengths ranged from one session to 2 years. Asanas (poses) were mentioned as yoga components in 369 (79%) interventions, but were either minimally or not at all described in 200 (54%) of these. Most interventions (74%, n =336) did not include home practice. Of the included studies, 151 were RCTs. RCT quality was rated as poor. Conclusions This review highlights the inadequate reporting and methodologic limitations of current yoga intervention research, which limits study interpretation and comparability. Recommendations for future methodology and reporting are discussed.
H-ras-transformed human bronchial epithelial cells (TBE-1) secrete a single major extracellular matrix metalloprotease which is not found in the normal parental cells. The enzyme is secreted in a ...latent form of 72 kDa, which can be activated to catalyze the cleavage of the basement membrane macromolecule type IV collagen. The substrates in their order of preference are: gelatin, type IV collagen, type V collagen, fibronectin, and type VII collagen; but the enzyme does not cleave the interstitial collagens or laminin. This protease is identical to gelatinase isolated from normal human skin explants, normal human skin fibroblasts, and SV40-transformed human lung fibroblasts. Based on its ability to initiate the degradation of type IV collagen in a pepsin-resistant portion of the molecule, it will be referred to as type IV collagenase. This enzyme is most likely the human analog of type IV collagenase detected in several rodent tumors, which has the same molecular mass and has been linked to their metastatic potential. Type IV collagenase consists of three domains. Two of them, the amino-terminal domain and the carboxyl-terminal domain, are homologous to interstitial collagenase and human and rat stromelysin. The middle domain, of 175 residues, is organized into three 58-residue head-to-tail repeats which are homologous to the type II motif of the collagen-binding domain of fibronectin. Type IV collagenase represents the third member of a newly recognized gene family coding for secreted extracellular matrix metalloproteases, which includes interstitial fibroblast collagenase and stromelysin.
Feeding a growing world population amidst climate change requires optimizing the reliability, resource use, and environmental impacts of food production. One way to assist in achieving these goals is ...to integrate beneficial plant microbiomes-i.e., those enhancing plant growth, nutrient use efficiency, abiotic stress tolerance, and disease resistance-into agricultural production. This integration will require a large-scale effort among academic researchers, industry researchers, and farmers to understand and manage plant-microbiome interactions in the context of modern agricultural systems. Here, we identify priorities for research in this area: (1) develop model host-microbiome systems for crop plants and non-crop plants with associated microbial culture collections and reference genomes, (2) define core microbiomes and metagenomes in these model systems, (3) elucidate the rules of synthetic, functionally programmable microbiome assembly, (4) determine functional mechanisms of plant-microbiome interactions, and (5) characterize and refine plant genotype-by-environment-by-microbiome-by-management interactions. Meeting these goals should accelerate our ability to design and implement effective agricultural microbiome manipulations and management strategies, which, in turn, will pay dividends for both the consumers and producers of the world food supply.
Objectives This report describes the extended follow-up of a cohort of 46 399 automobile manufacturing workers with potential exposure to metalworking fluids (MWF). The outcomes of interest were ...cancers of the esophagus, stomach, colon, rectum, liver, pancreas, larynx, skin, prostate, and brain, as well as leukemia. Additional follow-up increased the power to detect modest elevations in mortality rates in association with specific types of MWF, including synthetic fluids not in widespread use until the 1970s.Methods Standardized mortality ratios (SMR) were computed for the most recent 10 years of follow-up, as well as for the entire study period. Adjusted relative risks (RR) were estimated in Poisson regression models with categorical variables for cumulative exposure to each type of MWF and in proportional hazards models with continuous exposure variables.Results Associations were found between straight MWF and esophageal, laryngeal and rectal cancer; soluble MWF and cancer of the esophagus, larynx, skin, and brain; synthetic MWF and cancer of the esophagus, liver, and prostate. The elevated RR values were modest in magnitude (1.5 to 2.0). SMR values were increased for stomach, liver, and pancreatic cancer and also for leukemia in the last 10 years of follow-up. The SMR values were also elevated for stomach and liver cancer among the persons recently hired. Conclusions The results provide further evidence that exposure to metalworking fluids causes cancer among workers in automobile manufacturing. Although airborne exposures declined over the study period, this study suggests that modest risk of several digestive cancers, as well as prostatic cancer and leukemia, may persist at current levels of exposure to water-based metalworking fluids.
Occupations with mineral oil exposure have been associated with bladder cancer in population-based case-control studies. The authors report results from the first cohort study to examine bladder ...cancer incidence in relation to quantitative exposures to metalworking fluids (MWFs), based on 21,999 male Michigan automotive workers, followed from 1985 through 2004. Cox regression was used to estimate hazard ratios based on categorical exposure variables for straight, soluble, and synthetic MWFs, as well as duration of exposure to ethanolamines and nitrosamines. Penalized splines were also fit to estimate the functional form of the exposure-response relation. Increased bladder cancer risk was associated with straight MWFs but not with any other exposure. The hazard ratio increased with cumulative exposure to a maximum of 2-fold observed at 75 mg/m3-year straight MWF exposure (lagged 20 years). Calendar time windows relevant to polycyclic aromatic hydrocarbon exposure were examined but could not be distinguished from the lagged (10-, 20-year) metrics. No association was observed between any exposure and incident lung cancer, suggesting that smoking is unlikely to confound the associations observed here. The quantitative relation with straight MWFs strengthens the evidence for mineral oils as a bladder carcinogen.
Objectives Cervical cancer is caused by human papilloma virus (HPV). However, only a small proportion of women infected with HPV, progress to cervical cancer. Other co-factors must therefore be ...necessary to cause cervical cancer. We examined cervical cancer in relation to occupational exposure to metalworking fluids (MWF), which are complex mixtures containing several known carcinogens. Methods A cohort of 4374 female autoworkers was followed from 1985-2004 for cancer diagnosis. Based on an elevated standardized incidence rate (SIR), we focused on cervical cancer in an internal analysis. Pooled logistic regression was used to model the relationship between exposure to three different types of MWF, selected constituents, and incidence of cervical cancer. Results Based on 40 cases, the SIR was statistically significantly elevated for both race specific subgroups: 3.30 and 2.43, respectively for Caucasian and African American women. The standard mortality ratio (SMR) was also statistically significantly elevated for Caucasian women (3.44) based on seven observed deaths. There was no association with oil-based straight fluid. Relative risks for soluble and synthetic MWF and nitrosamines were modestly elevated but not statistically significant. Conclusions Water-based MWF may play a role in the etiology of cervical cancer. Further studies in larger cohorts of women are needed to clearly establish this relationship.
Alcohol consumption interacts with tobacco use to increase the risk of head and neck squamous cell carcinoma (HNSCC). Alcohol is eliminated through oxidation by alcohol dehydrogenase (ADH). The ADH1C ...gene is polymorphic and the ADH1C*1 allele metabolizes ethanol to acetaldehyde at a higher rate than the variant ADH1C*2 allele. This polymorphism has been reported to alter the risk of HNSCC associated with alcohol use, although the literature differs in the estimates of both the magnitude and direction of this effect modification. We have investigated the association between the established risk factors for HNSCC and variant genotypes of ADH1C in a case-control study in the greater Boston area. ADH1C genotypes were determined from 521 cases and 599 population-based controls. The odds ratio (OR) for HNSCC associated with >26 drinks per week was 3.7 95% confidence interval (95% CI), 2.4-5.7, whereas the OR for smoking >58 pack-years was 5.6 (95% CI, 3.8-8.4). The combination of heavy smoking and heavy drinking significantly interacted to produce an OR of 17.3 (95% CI, 7.8-38.3). In cases and controls, respectively, 16% and 14% were ADH1C*1-1, 46% and 46% were ADH1C*1-2 and 38% and 40% were ADH1C*2-2. There was a significant interaction of alcohol use and genotype (P = 0.05), with an estimated oral cancer risk in heavy drinkers of 7.1 (95% CI, 2.3-22.0) for homozygous variants compared with an OR of 2.3 (95% CI, 1.4-3.8) for ADH1C homozygous wild type or heterozygous individuals (controlling for smoking, age, race, and gender). These findings suggest that the ADH1C*2-2 genotype is associated with susceptibility to smoking and drinking-related HNSCC by modifying the biologically effective dose of alcohol.
The National Electronic Injury Surveillance System reports that the fingers and hand are the most frequent body parts injured at work and treated in hospital emergency departments. In this study, we ...describe the type, location, and severity of occupational hand injuries among 1166 patients recruited from 23 occupational health clinics in five New England states. Subjects ranged in age from 18 to 77 years, with a mean of 37.2 years (SD, 11.4), and approximately 75% were men. In decreasing order of frequency, subjects were employed in machine trades, service work, structural work, and less frequently, in benchwork, professional, technical managerial and clerical, and sales work. The majority of subjects (83.4%) had a single type of injury: 62.6% were lacerations, 13.1 % were crush injuries, 8.0% were avulsions, and 6.1% were punctures. Metal items, such as nails, metal stock, and burrs accounted for 38.4% of the injuries, followed by hand tools with blades and powered machinery (24.4% and 12.3%, respectively). Hand tools with blades were least likely to result in multiple types of injuries, whereas powered machines or nonpowered hand tools were more likely to result in multiple types of injuries than other injury sources. The generalizability of these results should be limited to clinic-based patients employed in similar occupations. The results of this study may suggest possible prevention strategies for acute traumatic hand injuries.
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