340 research outputs found
Predicting lung cancer recurrence from circulating tumour DNA. Commentary on 'Phylogenetic ctDNA analysis depicts early-stage lung cancer evolution'
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Risk of renal cell carcinoma in relation to blood telomere length in a population-based case–control study
Background: There are few known risk factors for renal cell carcinoma (RCC). Two small hospital-based case–control studies suggested an association between short blood telomere length (TL) and increased RCC risk. Methods: We conducted a large population-based case–control study in two metropolitan regions of the United States comparing relative TL in DNA derived from peripheral blood samples from 891 RCC cases and 894 controls. Odds ratios and 95% confidence intervals were estimated using unconditional logistic regression in both unadjusted and adjusted models. Results: Median TL was 0.85 for both cases and controls (P=0.40), and no differences in RCC risk by quartiles of TL were observed. Results of analyses stratified by age, sex, race, tumour stage, and time from RCC diagnosis to blood collection were similarly null. In multivariate analyses among controls, increasing age and history of hypertension were associated with shorter TL (P<0.001 and P=0.07, respectively), and African Americans had longer TL than Caucasians (P<0.001). Conclusion: These data do not support the hypothesis that blood TL is associated with RCC. This population-based case–control study is, to our knowledge, the largest investigation to date of TL and RCC
Design management: changing roles of the professions
This paper sets out to explore how recent changes in
procurement in construction have affected the roles that
professions play in the design process. It discusses how
professions that traditionally took the role of design
manager now find themselves participating within
previously unforeseen contexts, working in multidisciplinary
teams led by contractors and with changed
responsibilities at the design stage. Supply chain members
who were not previously involved during the early project
phases are being engaged at the earliest phases of the
project life cycle and even taking leadership roles while
designers sometimes work as supply chain partners.
A study of design in construction and other sectors shows
that in dealing with design management issues it is critical
to deepen appreciation for the unique characteristics of
design and the design process. The paper argues that
contractors and designers taking on design management
roles in a dynamic industry seeking to explore best
practice and innovative approaches to procurement and in
the delivery of projects need to acquire new skills,
management education and develop the necessary
qualities
Condition Indices as Surrogates of Energy Density and Lipid Content in Juveniles of Three Fish Species
To guide the selection of condition indices for juvenile fishes, we compared the ability of several indirect condition indices (those based on length-mass relationships, the hepatosomatic index, and relative lipid estimates from the Distell fish fatmeter) to assess energy density and lipid content of Summer Flounder Paralichthys dentatus, Striped BassMorone saxatilis, and Atlantic Croakers Micropogonias undulatus. These species use estuarine areas as nurseries, but they have different life history strategies and ecological niches that affect their energy storage strategies. We tested hypotheses that differences in the distribution and role of lipids as energy stores among species would influence the suitability of condition indices for estimating energy and lipid content. Length-based indices were most suitable for estimating energy and lipid content of juvenile Summer Flounder and Striped Bass, suggesting that length-based indices may be appropriate for juveniles that store energy as proteins (i.e., juveniles with low lipid content). The fatmeter suitably predicted energy and lipid content of Atlantic Croakers, indicating its potential for assessing condition of juveniles that store lipids for migration and that display a high range of observed lipid content. Even though a small size range was examined, fish length improved predictions of energy and lipid content for some of the indirect condition indices for Atlantic Croakers and Summer Flounder, suggesting that fish length should be considered when developing relationships among measures of condition. The selection of condition indices should be tailored to the life stage and species of interest based on the energy and lipid storage strategies used by the fish
Childhood Brain Tumours: Associations With Parental Occupational Exposure to Solvents
Background: Parental occupational exposures have been associated with childhood brain tumours (CBT), but results are inconsistent. Few studies have studied CBT risk and parental solvent exposure, suggesting a possible association. We examined the association between CBT and parental occupational exposure to solvents in a case–control study.Methods: Parents of 306 cases and 950 controls completed detailed occupational histories. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for both maternal and paternal exposure to benzene, other aromatics, aliphatics and chlorinated solvents in key time periods relative to the birth of their child. Adjustments were made for matching variables (child’s age, sex and state of residence), best parental education and occupational exposure to diesel exhaust.Results: An increased risk of CBT was observed with maternal occupational exposures to chlorinated solvents (OR=8.59, 95% CI 0.94–78.9) any time before birth. Paternal exposure to solvents in the year before conception was associated with an increased CBT risk: OR=1.55 (95% CI 0.99–2.43). This increased risk appeared to be mainly attributable to exposure to aromatic solvents: OR=2.72 (95% CI 0.94–7.86) for benzene and OR=1.76 (95% CI 1.10–2.82) for other aromatics.Conclusions: Our results indicate that parental occupational exposures to solvents may be related to an increased risk of CBT
Healthcare costs and utilization for Medicare beneficiaries with Alzheimer's
<p>Abstract</p> <p>Background</p> <p>Alzheimer's disease (AD) is a neurodegenerative disorder incurring significant social and economic costs. This study uses a US administrative claims database to evaluate the effect of AD on direct healthcare costs and utilization, and to identify the most common reasons for AD patients' emergency room (ER) visits and inpatient admissions.</p> <p>Methods</p> <p>Demographically matched cohorts age 65 and over with comprehensive medical and pharmacy claims from the 2003–2004 MEDSTAT MarketScan<sup>® </sup>Medicare Supplemental and Coordination of Benefits (COB) Database were examined: 1) 25,109 individuals with an AD diagnosis or a filled prescription for an exclusively AD treatment; and 2) 75,327 matched controls. Illness burden for each person was measured using Diagnostic Cost Groups (DCGs), a comprehensive morbidity assessment system. Cost distributions and reasons for ER visits and inpatient admissions in 2004 were compared for both cohorts. Regression was used to quantify the marginal contribution of AD to health care costs and utilization, and the most common reasons for ER and inpatient admissions, using DCGs to control for overall illness burden.</p> <p>Results</p> <p>Compared with controls, the AD cohort had more co-morbid medical conditions, higher overall illness burden, and higher but less variable costs (10,369; Coefficient of variation = 181 vs. 324). Significant excess utilization was attributed to AD for inpatient services, pharmacy, ER visits, and home health care (all p < 0.05). In particular, AD patients were far more likely to be hospitalized for infections, pneumonia and falls (hip fracture, syncope, collapse).</p> <p>Conclusion</p> <p>Patients with AD have significantly more co-morbid medical conditions and higher healthcare costs and utilization than demographically-matched Medicare beneficiaries. Even after adjusting for differences in co-morbidity, AD patients incur excess ER visits and inpatient admissions.</p
Spatial-temporal analysis of non-Hodgkin lymphoma in the NCI-SEER NHL case-control study
<p>Abstract</p> <p>Background</p> <p>Exploring spatial-temporal patterns of disease incidence through cluster analysis identifies areas of significantly elevated or decreased risk, providing potential clues about disease risk factors. Little is known about the etiology of non-Hodgkin lymphoma (NHL), or the latency period that might be relevant for environmental exposures, and there are no published spatial-temporal cluster studies of NHL.</p> <p>Methods</p> <p>We conducted a population-based case-control study of NHL in four National Cancer Institute (NCI)-Surveillance, Epidemiology, and End Results (SEER) centers: Detroit, Iowa, Los Angeles, and Seattle during 1998-2000. Using 20-year residential histories, we used generalized additive models adjusted for known risk factors to model spatially the probability that an individual had NHL and to identify clusters of elevated or decreased NHL risk. We evaluated models at five different time periods to explore the presence of clusters in a time frame of etiologic relevance.</p> <p>Results</p> <p>The best model fit was for residential locations 20 years prior to diagnosis in Detroit, Iowa, and Los Angeles. We found statistically significant areas of elevated risk of NHL in three of the four study areas (Detroit, Iowa, and Los Angeles) at a lag time of 20 years. The two areas of significantly elevated risk in the Los Angeles study area were detected only at a time lag of 20 years. Clusters in Detroit and Iowa were detected at several time points.</p> <p>Conclusions</p> <p>We found significant spatial clusters of NHL after allowing for disease latency and residential mobility. Our results show the importance of evaluating residential histories when studying spatial patterns of cancer.</p
Analysis of Environmental Chemical Mixtures and Non-Hodgkin Lymphoma Risk in the NCI-SEER NHL Study
Background: There are several suspected environmental risk factors for non-Hodgkin lymphoma (NHL). The associations between NHL and environmental chemical exposures have typically been evaluated for individual chemicals (i.e., one-by-one).
Objectives: We determined the association between a mixture of 27 correlated chemicals measured in house dust and NHL risk.
Methods: We conducted a population-based case–control study of NHL in four National Cancer Institute–Surveillance, Epidemiology, and End Results centers—Detroit, Michigan; Iowa; Los Angeles County, California; and Seattle, Washington—from 1998 to 2000. We used weighted quantile sum (WQS) regression to model the association of a mixture of chemicals and risk of NHL. The WQS index was a sum of weighted quartiles for 5 polychlorinated biphenyls (PCBs), 7 polycyclic aromatic hydrocarbons (PAHs), and 15 pesticides. We estimated chemical mixture weights and effects for study sites combined and for each site individually, and also for histologic subtypes of NHL.
Results: The WQS index was statistically significantly associated with NHL overall [odds ratio (OR) = 1.30; 95% CI: 1.08, 1.56; p = 0.006; for one quartile increase] and in the study sites of Detroit (OR = 1.71; 95% CI: 1.02, 2.92; p = 0.045), Los Angeles (OR = 1.44; 95% CI: 1.00, 2.08; p = 0.049), and Iowa (OR = 1.76; 95% CI: 1.23, 2.53; p = 0.002). The index was marginally statistically significant in Seattle (OR = 1.39; 95% CI: 0.97, 1.99; p = 0.071). The most highly weighted chemicals for predicting risk overall were PCB congener 180 and propoxur. Highly weighted chemicals varied by study site; PCBs were more highly weighted in Detroit, and pesticides were more highly weighted in Iowa.
Conclusions: An index of chemical mixtures was significantly associated with NHL. Our results show the importance of evaluating chemical mixtures when studying cancer risk
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