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Although some consensus has emerged among the scientific and regulatory communities that the urban ambient atmospheric mix of combustion related pollutants is a determinant of population health, the relative toxicity of the chemical and physical components of this complex mixture remains unclear. Daily mortality rates and concurrent data on sizefractionated particulate mass and gaseous pollutants were obtained in eight of Canada's largest cities from 1986 to 1996 inclusive in order to examine the relative toxicity of the components of the mixture of ambient air pollutants to which Canadians are exposed. Positive and statistically significant associations were observed between daily variations in both gas- and particulate-phase pollution and daily fluctuations in mortality rates. The association between air pollution and mortality could not be explained by temporalvariation in either mortality rates or weather factors. Fine particulate mass (less than 2.5 µm in average aerometric diameter) was a stronger predictor of mortality than coarse mass (between 2.5 and 10 µm). Size-fractionated particulate mass explained 28% of the total health effect of the mixture, with the remaining effects accounted for by the gases. Forty-seven elemental concentrations were obtained for the fine and coarse fraction using nondestructive x-ray fluorescence techniques. Sulfate concentrations were obtained by ion chromatography. Sulfate ion, iron, nickel, and zinc from the fine fraction were most strongly associated with mortality. The total effect of these four components was greater than that for fine mass alone, suggesting that the characteristics of the complex chemical mixture in the fine fraction maybe a better predictor of mortality than mass alone. However,the variation in the effects of the constituents of the fine fraction between cities was greater than the variation in the mass effect, implying that there are additional toxic components of fine particulate matter not examined in this study whose concentrations and effects vary between locations. One of these components, carbon, represents half the mass of fine particulate matter. We recommend that measurements of elemental and organiccarbon be undertaken in Canadian urban environments to examine their potential effects on human health. [ABSTRACT FROM AUTHOR]

Background: Advantages of using stereotactic body radiation therapy to treat prostate cancer include short treatment times, decreased costs, and limited toxicity. Randomized trial outcomes comparing 5-fraction stereotactic body radiation therapy to conventionally fractionated radiotherapy or hypo-fractionated radiation therapy are pending., Objective: We report the 10-year experience with 5-fraction stereotactic body radiation therapy and hypo-fractionated radiation therapy at two Canadian centers., Material and Methods: Patients with low- or intermediate-risk prostate cancer treated with stereotactic body radiation therapy alone (35-40 Gy in 5 fractions) or hypo-fractionated radiation therapy alone (60-62 Gy in 20 fractions) in the period of July 2010 and June 2020. The biochemical relapse-free survival, PSA nadir, interval time to PSA nadir, time to biochemical recurrence (2 ng/ml above PSA nadir) and overall survival were reviewed. Outcomes between treatment groups were compared after propensity-matching by patient baseline characteristics. Kaplan-Meier curves were used to assess biochemical relapse-free survival and overall survival., Results: We identified 205 and 513 patients with low or intermediate-risk prostate cancer who were treated with stereotactic body radiation therapy or hypo-fractionation, respectively. Intermediate-risk category composed 81% and 95% of the stereotactic body radiation therapy and hypo-fractionated radiation therapy cohorts, respectively. After a median follow up of 58.6 months for the stereotactic body radiation therapy cohort and 45.0 months for the hypo-fractionated cohort, biochemical relapse-free survival and overall survival were not significantly different between treatment groups. The 5-year biochemical relapse-free survival rates were 92.1% and 93.6% and overall survival rates were 96.4% and 95.0% for the stereotactic body radiation therapy and hypo-fractionated cohorts, respectively, after propensity-matching. Stereotactic body radiation therapy resulted in a significantly lower PSA nadir (0.18 ng/ml) compared to hypo-fractionated radiation therapy (0.48 ng/ml) in patients with low-risk prostate cancer. Mean time to biochemical recurrence was not different between treatment groups., Conclusions: Stereotactic body radiation therapy is an effective treatment option for low and intermediate-risk prostate cancer with encouraging biochemical relapse-free survival and overall survival rates comparable with hypo-fractionated radiation therapy., (© 2023 The Authors. The Prostate published by Wiley Periodicals LLC.)

Purpose: The objectives were: (1) to translate and adapt the International Society of Wheelchair Professional (ISWP) basic Wheelchair Service Provision Test (bWSPT) into French-Canadian and (2) to conduct a preliminary evaluation of the French-Canadian version of the ISWP bWSPT internal consistency and relations with other variables among French-Canadian occupational therapy students., Methods: For Phase 1, based on the International Test Commission Guidelines for Translating and Adapting Tests, a forward translation and adaptation from English to French-Canadian was conducted by a translation team. For Phase 2, the validity evidence of the French-Canadian bWSPT was evaluated through internal consistency and comparison of bWSPT scores and final grades of a wheelchair-specific course with a sample of occupational therapy students (positive, moderate correlation hypothesized). Internal consistency was measured with Cronbach's α . The correlation was calculated using the Spearman's Rank Correlation Coefficient., Results: For phase 1, 61 of 167 items of the forward adaptation were revised and modified. All revisions were a consensus by the translation team. For phase 2, we found a Cronbach's α of 0.50 and a correlation of ⍴ = 0.27 ( p  = 0.43) between the bWSPT French-Canadian version and the wheelchair-specific course final grade. The low variability of the data may explain the lower-than-expected correlation. Other possible data-driven reasons have been explored using post-hoc analysis., Conclusion: The ISWP bWSPT, French-Canadian version, is not internally consistent and demonstrates a non-statistically significant, positive, weak correlation with the final grade of a wheelchair service provision-specific course among a cohort of 35 occupational therapy students.IMPLICATIONS FOR REHABILITATIONThe lack of adequately educated wheelchair service providers is a contributing factor to inappropriate wheelchair provision worldwide.The ISWP Wheelchair Service Provision Basic Test (ISWP bWSPT) has been created to evaluate competency among wheelchair service providers and provides a standardized test recognized internationally.A French-Canadian version of the ISWP bWSPT allows competency testing of French-speaking wheelchair service providers across Canada.This study shows that the French-Canadian version of the test is not internally consistent and has a low correlation with a wheelchair provision-specific course among a cohort of 35 occupational therapy students at a French-Canadian university suggesting further refinement is required to improve its measurement properties in this population of test-takers.

Background: We conducted a population-based case-control study in Montreal, Canada, to explore associations between hundreds of occupational circumstances and several cancer sites, including colon., Methods: We interviewed 497 male patients with a pathologically confirmed diagnosis of colon cancer, 1514 controls with cancers at other sites, and 533 population-based controls. Detailed job histories and relevant potential confounding variables were obtained, and the job histories were translated by a team of chemists and industrial hygienists into a history of occupational exposures., Results: We found that there was reasonable evidence of associations for men employed in nine industry groups (adjusted odds ranging from 1.1 to 1.6 per a 10-year increase in duration of employment), and in 12 job groups (OR varying from 1.1 to 1.7). In addition, we found evidence of increased risks by increasing level of exposures to 21 occupational agents, including polystyrene (OR for "substantial" exposure (OR(subst)) = 10.7), polyurethanes (OR(subst) = 8.4), coke dust (OR(subst) = 5.6), mineral oils (OR(subst) = 3.3), polyacrylates (OR(subst) = 2.8), cellulose nitrate (OR(subst) = 2.6), alkyds (OR(subst) = 2.5), inorganic insulation dust (OR(subst) = 2.3), plastic dusts (OR(subst) = 2.3), asbestos (OR(subst) = 2.1), mineral wool fibers (OR(subst) = 2.1), glass fibers (OR(subst) = 2.0), iron oxides (OR(subst) = 1.9), aliphatic ketones (OR(subst) = 1.9), benzene (OR(subst) = 1.9), xylene (OR(subst) = 1.9), inorganic acid solutions (OR(subst) = 1.8), waxes, polishes (OR(subst) = 1.8), mononuclear aromatic hydrocarbons (OR(subst) = 1.6), toluene (OR(subst) = 1.6), and diesel engine emissions (OR(subst) = 1.5). Not all of these effects are independent because some exposures occurred contemporaneously with others or because they referred to a group of substances., Conclusions: We have uncovered a number of occupational associations with colon cancer. For most of these agents, there are no published data to support or refute our observations. As there are few accepted risk factors for colon cancer, we suggest that new occupational and toxicologic studies be undertaken focusing on the more prevalent substances reported herein., (Copyright 2001 Wiley-Liss, Inc.)