2,850 research outputs found
A healthy lifestyle index and cancer: Using a multifactor lifestyle exposure to estimate cancer incidence and survival among Norwegian women
Background: Cancer is the leading cause of death in Norway, and lifestyle behaviors are a major contributor to cancer risk. This thesis aimed to investigate the association between a healthy lifestyle index (HLI) and cancer incidence and survival among women in Norway.
Methods: The study used data from the Norwegian Women and Cancer Study, a national prospective cohort of approximately 170,000 randomly selected women. The HLI was constructed based on physical activity, body mass index, smoking habits, alcohol intake, and habitual intake of major food groups. Cox proportional hazard models and restricted cubic splines were used to estimate associations between the HLI score and cancer incidence, HLI score change and cancer incidence, and prediagnostic HLI score and survival.
Results: We observed that a higher HLI score was associated with lower risks of postmenopausal breast, colorectal, lung, postmenopausal endometrial, pancreatic, and kidney cancers, but not postmenopausal ovarian cancer. Regardless of baseline HLI score, greater positive HLI score changes were associated with a lower risk of lifestyle-related cancers combined. Additionally, a higher prediagnostic HLI score was associated with lower all-cause mortality and, weakly, with lower breast cancer mortality among women diagnosed with breast cancer. Associations were also negative, but weak, for women diagnosed with colorectal cancer. No associations were observed for lung cancer mortality. Smoking was particularly strong in driving several associations.
Conclusion: A healthy lifestyle, where smoking avoidance is a priority, should be promoted and facilitated throughout all adult ages to reduce the risk of cancer in the Norwegian general population of women. However, more research is required to understand the potential impact of lifestyle factors and overall lifestyle on cancer survival
International diversification with factor funds
We propose a new investment strategy employing "factor funds" to systematically enhance the meanvariance efficiency of international diversification. Our approach is motivated by the increasing evidence that size (SMB), book-to-market (HML), and momentum (MOM) factors, along with the market factor, adequately describe international stock returns, and by the direct link between investors' portfolio choice problems and international asset pricing theories and tests. Using data from 10 developed countries during the period 1981-2008, we show that the "augmented" optimal portfolio involving local factor funds substantially outperforms the "benchmark" optimal portfolio comprising country market indices only as measured by their portfolio Sharpe ratios. This strongly rejects the intersection hypothesis which posits that the local factor funds do not span investment opportunities beyond what country market indices do. Among the three classes of factor funds, HML funds contribute most to the efficiency gains. In addition, the local version of factor funds outperforms the global factor funds. The added gains from local factor diversification are significant for both in-sample and out-of-sample periods, and for a realistic range of additional investment costs for factor funds, and remain robust over time. Copyright © 2010 INFORMS.preprin
Education Level and Self-Reported Cardiovascular Disease in Norway—The Tromsø Study, 1994–2016
Background: Cardiovascular disease (CVD) is a leading source of morbidity and mortality, and research has shown education level to be a risk factor for the disease. The aim of this study was to investigate the association between education level and self-reported CVD in Tromsø, Norway. Methods: This prospective cohort study included 12,400 participants enrolled in the fourth and seventh surveys of the Tromsø Study (Tromsø4 and Tromsø7) in 1994–1995 and 2015–2016, respectively. Logistic regression was used to obtain odds ratios (ORs) and 95% confidence intervals (CIs). Results: For every 1-level increase in education, the age-adjusted risk of self-reported CVD decreased by 9% (OR = 0.91, 95% CI: 0.87–0.96), but after adjustment for covariates, the association was weaker (OR = 0.96, 95% CI: 0.92–1.01). The association was stronger for women (OR = 0.86, 95% CI: 0.79–0.94) than men (OR = 0.91, 95% CI: 0.86–0.97) in age-adjusted models. After adjustment for covariates, the associations for women and men were similarly weak (women: OR = 0.95, 95% CI: 0.87–1.04; men: OR = 0.97, 95% CI: 0.91–1.03). In age-adjusted-models, higher education level was associated with a lower risk of self-reported heart attack (OR = 0.90, 95% CI: 0.84–0.96), but not stroke (OR = 0.97, 95% CI: 0.90–1.05) or angina (OR = 0.98, 95% CI: 0.90–1.07). There were no clear associations observed in the multivariable models for CVD components (heart attack: OR = 0.97, 95% CI: 0.91–1.05; stroke: OR = 1.01, 95% CI: 0.93–1.09; angina: OR = 1.04, 95% CI: 0.95–1.14). Conclusions: Norwegian adults with a higher education level were at lower risk of self-reported CVD. The association was present in both genders, with a lower risk observed in women than men. After accounting for lifestyle factors, there was no clear association between education level and self-reported CVD, likely due to covariates acting as mediators
A comparison of univariate and multivariate gene selection techniques for classification of cancer datasets
BACKGROUND: Gene selection is an important step when building predictors of disease state based on gene expression data. Gene selection generally improves performance and identifies a relevant subset of genes. Many univariate and multivariate gene selection approaches have been proposed. Frequently the claim is made that genes are co-regulated (due to pathway dependencies) and that multivariate approaches are therefore per definition more desirable than univariate selection approaches. Based on the published performances of all these approaches a fair comparison of the available results can not be made. This mainly stems from two factors. First, the results are often biased, since the validation set is in one way or another involved in training the predictor, resulting in optimistically biased performance estimates. Second, the published results are often based on a small number of relatively simple datasets. Consequently no generally applicable conclusions can be drawn. RESULTS: In this study we adopted an unbiased protocol to perform a fair comparison of frequently used multivariate and univariate gene selection techniques, in combination with a ränge of classifiers. Our conclusions are based on seven gene expression datasets, across several cancer types. CONCLUSION: Our experiments illustrate that, contrary to several previous studies, in five of the seven datasets univariate selection approaches yield consistently better results than multivariate approaches. The simplest multivariate selection approach, the Top Scoring method, achieves the best results on the remaining two datasets. We conclude that the correlation structures, if present, are difficult to extract due to the small number of samples, and that consequently, overly-complex gene selection algorithms that attempt to extract these structures are prone to overtraining
Comparison of the safety and efficacy of a fixed-dose combination regimen and separate formulations for pulmonary tuberculosis treatment
OBJECTIVES: Fixed-dose combination formulations, which simplify the administration of drugs and prevent the development of drug resistance, have been recommended as a standard anti-tuberculosis treatment regimen. However, the composition and dosage recommendations for fixed-dose combination formulations differ from those for separate formulations. Thus, questions about the effectiveness and side effects of combination formulations remain. The aim of this study was to compare the safety and efficacy of these two types of anti-tuberculosis regimens for pulmonary tuberculosis treatment. METHOD: A prospective, randomized controlled study was conducted using the directly observed treatment short-course strategy. Patients were randomly allocated to one of two short-course regimens. One year after completing the treatment, these patients’ outcomes were analyzed. ClinicalTrials.gov: NCT00979290. RESULTS: A total of 161 patients were enrolled, 142 of whom were evaluable for safety assessment. The two regimens had a similar incidence of adverse effects. In the per-protocol population, serum bilirubin concentrations at the peak level, at week 4, and at week 8 were significantly higher for the fixed-dose combination formulation than for the separate formulations. All patients had negative sputum cultures at the end of the treatment, and no relapse occurred after one year of follow-up. CONCLUSIONS: In this randomized study, transient higher serum bilirubin levels were noted for the fixed-dose combination regimen compared with the separate formulations during treatment. However, no significant difference in safety or efficacy was found between the groups when the directly observed treatment short-course strategy was used
Structural and functional correlation of the trypsin-digested Ca2+ release channel of skeletal muscle sarcoplasmic reticulum.
The effect of trypsin digestion on the (i) fragmentation pattern, (ii) activity, (iii) [3H]ryanodine binding, and (iv) sedimentation behavior of the skeletal sarcoplasmic reticulum (SR) ryanodine receptor-Ca2+ release channel complex has been examined. Mild tryptic digestion of heavy, junctional-derived SR vesicles resulted in the rapid disappearance of the high molecular weight (Mr approximately 400,000) Ca2+ release channel protein on sodium dodecyl sulfate gels and appearance of bands of lower Mr upon immunoblot analysis, without an appreciable effect on [3H]ryanodine binding or the apparent S value (30 S) of the 3-[3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (Chaps)-solubilized channel complex. Further degradation to bands of Mr greater than 70,000 on immunoblots correlated with a reduction of channel size from 30 S to 10-15 S and loss of high affinity [3H]ryanodine binding to the trypsinized receptor, while low affinity [3H]ryanodine binding and [3H]ryanodine bound prior to digestion were retained. Parallel 45Ca2+ efflux measurements also indicated retention of the Ca2+, Mg2+, and ATP regulatory sites, although Ca2+-induced 45Ca2+ release rates were changed. In planar lipid bilayer-single channel measurements, addition of trypsin to the cytoplasmic side of the high conductance (100 pS in 50 mM Ca2+), Ca2+-activated SR Ca2+ channel initially increased the fraction of channel open time and was followed by a complete and irreversible loss of channel activity. Trypsin did not change the unitary conductance, and was without effect on single channel activity when added to the lumenal side of the channel
Application of ultrasonic inspection in monitoring dynamic healing of mandibular fracture in rabbit model
AbstractObjectiveTo investigate the feasibility of ultrasonic diagnosis for monitoring fracture healing.MethodsThirty rabbit models with fraction of mandible body were established by surgically removing partial lower jawbone. At the 1st, 2nd, 4th, 6th, 8th and 12th week after the operation, they were examined by X-ray and ultrasound, respectively. All detection results were scored according to a generally accepted standard. Spearman rank correlation analysis was conducted to explore the relationship between the results of the two inspection methods.ResultsIn each healing stage, the results of the ultrasonic inspection were basically consistent with those of the X-ray examination, as supported by a Spearman rank correlation coefficient of 0.892 (P<0.001).ConclusionsNon-invasive ultrasonic inspection can be used instead of X-ray examination to monitor and diagnose fracture healing
Dichloridobis[ethyl 2-(2-amino-1,3-thiaÂzol-4-yl)acetate-κ2 O,N 3]cadmium
The asymmetric unit of the title compound, [CdCl2(C7H10N2O2S)2], contains two complex molecules with similar configurations. The CdII atoms are each six-coordinated by two thiazole N and two carbonyl O atoms from the 2-(2-amino-1,3-thiazol-4-yl)acetate ligand, and by two Cl− anions in a distorted octaÂhedral geometry. In the crystal, intra- and interÂmolecular N—H⋯Cl hydrogen bonds create parallel chains along [1-10]. C—H⋯Cl interÂactions also occur
Combined Lifestyle Behaviors and the Incidence of Common Cancer Types in the Norwegian Women and Cancer Study (NOWAC)
Introduction: Only a small number of studies have examined the impact of combined lifestyle behaviors on cancer incidence, and never in a Norwegian population.
Purpose: To examine linear and nonlinear associations of combined lifestyle factors, assessed through a healthy lifestyle index (HLI), with the incidence of postmenopausal breast, colorectal, lung, postmenopausal endometrial, postmenopausal ovarian, pancreatic, and kidney cancer among women in Norway.
Methods: This prospective study included 96,869 women enrolled in the Norwegian Women and Cancer (NOWAC) cohort. Baseline information on lifestyle factors was collected between 1996 and 2004. The HLI was constructed from five lifestyle factors: physical activity level, body mass index, smoking, alcohol consumption, and diet. Each factor contributed 0 to 4 points to the HLI score, which ranged from 0 to 20, with higher scores representing a healthier lifestyle. Multiple imputation was used to handle missing data. Cox proportional hazard regression models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI). Restricted cubic splines were used to examine nonlinearity in the associations.
Results: The HRs for a one-point increment on the HLI score were 0.97 (95% CI: 0.96– 0.98) for postmenopausal breast cancer, 0.98 (0.96– 1.00) for colorectal cancer, 0.86 (0.84– 0.87) for lung cancer, 0.93 (0.91– 0.95) for postmenopausal endometrial cancer, 0.99 (0.96– 1.02) for postmenopausal ovarian cancer, 0.92 (0.89– 0.95) for pancreatic cancer, and 0.94 (0.91– 0.97) for kidney cancer. Nonlinearity was observed for the inverse associations between HLI score and the incidence of lung cancer and postmenopausal breast cancer.
Conclusion: Based on our results, healthier lifestyle, as assessed by the HLI score, was associated with lower incidence of postmenopausal breast, colorectal, lung, postmenopausal endometrial, pancreatic, and kidney cancer among women, although the magnitude and linearity varied. Adoption of healthier lifestyle behaviors should be a public health priority to reduce the cancer burden among Norwegian women
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