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Incidence of components of metabolic syndrome in the metabolically healthy obese over 9 years follow-up: the Atherosclerosis Risk In Communities study.
BackgroundSome obese adults are not afflicted by the metabolic abnormalities often associated with obesity (the 'metabolically healthy obese' (MHO)); however, they may be at increased risk of developing cardiometabolic abnormalities in the future. Little is known about the relative incidence of individual components of metabolic syndrome (MetSyn).MethodsWe used data from a multicenter, community-based cohort aged 45-64 years at recruitment (the Atherosclerosis Risk In Communities study) to examine the first appearance of any MetSyn component, excluding waist circumference. Body mass index (BMI, kg m-2) and cardiometabolic data were collected at four triennial visits. Our analysis included 3969 adults who were not underweight and free of the components of MetSyn at the initial visit. Participants were classified as metabolically healthy normal weight (MHNW), overweight (MHOW) and MHO at each visit. Adjusted hazard ratios (HR) and 95% confidence intervals were estimated with proportional hazards regression models.ResultsThe relative rate of developing each risk factor was higher among MHO than MHNW, with the strongest association noted for elevated fasting glucose (MHO vs MHNW, HR: 2.33 (1.77, 3.06)). MHO was also positively associated with elevated triglycerides (HR: 1.63 (1.27, 2.09)), low high-density lipoprotein-cholesterol (HR: 1.68 (1.32, 2.13)) and elevated blood pressure (HR: 1.54 (1.26, 1.88)). A similar, but less pronounced pattern was noted among the MHOW vs MHNW.ConclusionsWe conclude that even among apparently healthy individuals, obesity and overweight are related to more rapid development of at least one cardiometabolic risk factor, and that elevations in blood glucose develop most rapidly
Mechanisms regulating cAMP-mediated growth of bovine neonatal pulmonary artery smooth muscle cells
Easy on that trigger dad: a study of long term family photo retrieval
We examine the effects of new technologies for digital photography on people's longer term storage and access to collections of personal photos. We report an empirical study of parents' ability to retrieve photos related to salient family events from more than a year ago. Performance was relatively poor with people failing to find almost 40% of pictures. We analyze participants' organizational and access strategies to identify reasons for this poor performance. Possible reasons for retrieval failure include: storing too many pictures, rudimentary organization, use of multiple storage systems, failure to maintain collections and participants' false beliefs about their ability to access photos. We conclude by exploring the technical and theoretical implications of these findings
A framework for power analysis using a structural equation modelling procedure
BACKGROUND: This paper demonstrates how structural equation modelling (SEM) can be used as a tool to aid in carrying out power analyses. For many complex multivariate designs that are increasingly being employed, power analyses can be difficult to carry out, because the software available lacks sufficient flexibility. Satorra and Saris developed a method for estimating the power of the likelihood ratio test for structural equation models. Whilst the Satorra and Saris approach is familiar to researchers who use the structural equation modelling approach, it is less well known amongst other researchers. The SEM approach can be equivalent to other multivariate statistical tests, and therefore the Satorra and Saris approach to power analysis can be used. METHODS: The covariance matrix, along with a vector of means, relating to the alternative hypothesis is generated. This represents the hypothesised population effects. A model (representing the null hypothesis) is then tested in a structural equation model, using the population parameters as input. An analysis based on the chi-square of this model can provide estimates of the sample size required for different levels of power to reject the null hypothesis. CONCLUSIONS: The SEM based power analysis approach may prove useful for researchers designing research in the health and medical spheres
Measuring and Valuing Health-Related Quality of Life among Children and Adolescents in Mainland China - A Pilot Study
Background: The Child Health Utility 9D (CHU9D), a new generic preference-based health-related quality of life (HRQoL)
instrument, has been validated for use in young people in both the UK and Australia. The main objectives of this study were
to examine the feasibility of using a Chinese version of the CHU9D (CHU9D-CHN) to assess HRQoL and to investigate the
association of physical activity, homework hours and sleep duration with HRQoL in children and adolescents in Mainland
China.
Methods: Data were collected using a multi-stage sampling method from grades 4–12 students in May 2013 in Nanjing,
China. Consenting participants (N = 815) completed a self-administered questionnaire including the CHU9D-CHN instrument
and information on physical activity, homework and sleep duration, self-reported health status, and socio-demographic
characteristics. Descriptive and multivariate linear regression analyses were undertaken. CHU9D-CHN utility scores were
generated by employing two scoring algorithms currently available for the instrument, the first derived from UK adults
utilising the standard gamble (SG) valuation method and the second derived from Australian adolescents utilising the bestworst
scaling (BWS) method.
Results: It was found that CHU9D utility scores discriminated well in relation to self-reported health status and that better
health status was significantly associated with higher utility scores regardless of which scoring algorithm was employed
(both p,0.001). The adjusted mean utilities were significantly higher for physically active than inactive students (0.023 by
SG, 0.029 by BWS scoring methods, p,0.05). An additional hour of doing homework and sleep duration were, separately,
associated with mean utilities of 20.019 and 0.032 based on SG, and 20.021 and 0.040 according to BWS scoring algorithms
(p,0.01).
Conclusion: The CHU9D-CHN shows promise for measuring and valuing the HRQoL of children and adolescents in China.
Levels of self-reported physical activity, homework and sleep time were important influencers of utility scores
Generating mice with targeted mutations.
Journal ArticleMutational analysis is one of the most informative approaches available for the study of complex biological processes. It has been particularly successful in the analysis of the biology of bacteria, yeast, the nematode worm Caenorhabditis elegans and the fruit fly Drosophila melanogaster. Extension of this approach to the mouse, through informative, was far less successful relative to what has been achieved with these simpler model organisms. This is because it is not numerically practical in mice to use random mutagenesis to isolate mutations that affect a specified biological process of interest. Nonetheless, biological phenomena such as a sophisticated immune response, cancer, vascular disease or higher-order cognitive function, to mention just a few, must analyzed in organisms that show such phenomena, and for this reason geneticists and other researchers have turned to the mouse. Gene targeting, the means for creating mice with designed mutations in almost any gene, was developed as an alternative to the impractical use of random mutgenesis for pursing genetic analysis in the mouse. Now gene targeting has advanced the genomic manipulations possible in mice to a level that can be matched only in far simple organisms such as bacteria and yeast
Dealing with missing standard deviation and mean values in meta-analysis of continuous outcomes: a systematic review
Background: Rigorous, informative meta-analyses rely on availability of appropriate summary statistics or individual
participant data. For continuous outcomes, especially those with naturally skewed distributions, summary
information on the mean or variability often goes unreported. While full reporting of original trial data is the ideal,
we sought to identify methods for handling unreported mean or variability summary statistics in meta-analysis.
Methods: We undertook two systematic literature reviews to identify methodological approaches used to deal with
missing mean or variability summary statistics. Five electronic databases were searched, in addition to the Cochrane
Colloquium abstract books and the Cochrane Statistics Methods Group mailing list archive. We also conducted cited
reference searching and emailed topic experts to identify recent methodological developments. Details recorded
included the description of the method, the information required to implement the method, any underlying
assumptions and whether the method could be readily applied in standard statistical software. We provided a
summary description of the methods identified, illustrating selected methods in example meta-analysis scenarios.
Results: For missing standard deviations (SDs), following screening of 503 articles, fifteen methods were identified in
addition to those reported in a previous review. These included Bayesian hierarchical modelling at the meta-analysis
level; summary statistic level imputation based on observed SD values from other trials in the meta-analysis; a practical
approximation based on the range; and algebraic estimation of the SD based on other summary statistics. Following
screening of 1124 articles for methods estimating the mean, one approximate Bayesian computation approach and
three papers based on alternative summary statistics were identified. Illustrative meta-analyses showed that when
replacing a missing SD the approximation using the range minimised loss of precision and generally performed better
than omitting trials. When estimating missing means, a formula using the median, lower quartile and upper quartile
performed best in preserving the precision of the meta-analysis findings, although in some scenarios, omitting trials
gave superior results.
Conclusions: Methods based on summary statistics (minimum, maximum, lower quartile, upper quartile, median)
reported in the literature facilitate more comprehensive inclusion of randomised controlled trials with missing mean or
variability summary statistics within meta-analyses
Recognition of Face Identity and Emotion in Expressive Specific Language Impairment
Objective: To study face and emotion recognition in children with mostly expressive specific language impairment (SLI-E). Subjects and Methods: A test movie to study perception and recognition of faces and mimic-gestural expression was applied to 24 children diagnosed as suffering from SLI-E and an age-matched control group of normally developing children. Results: Compared to a normal control group, the SLI-E children scored significantly worse in both the face and expression recognition tasks with a preponderant effect on emotion recognition. The performance of the SLI-E group could not be explained by reduced attention during the test session. Conclusion: We conclude that SLI-E is associated with a deficiency in decoding non-verbal emotional facial and gestural information, which might lead to profound and persistent problems in social interaction and development. Copyright (C) 2012 S. Karger AG, Base
Re-irradiation of a second localization of idiopathic midline destructive disease in the head and neck area
Idiopathic midline destructive disease is a rare disease, characterized by a progressive ulceration and destruction of midline facial structures. We report a case with localization on the palate for which she received radiotherapy. Later she developed a second localization on the posterior pharyngeal wall for which she was re-irradiated, without severe sequels. Twice a complete regression was observed
Quality of life returns from basic research
<p>Abstract</p> <p>Background</p> <p>Assessing the consequences of research is an increasingly important task in research and innovation policy. This paper takes a broader view of those consequences than the conventional economic approach, placing researchers and their activities in the centre of the assessment process and examining results for professional practice and general education as well as contributions to knowledge.</p> <p>Methods</p> <p>The paper uses historical and documentary analysis to illustrate the approach, focusing on U.S. biomedicine over the past century. At aggregate level, the analysis attributes portions of the change in aggregate health indicators to research and research-based institutions, through several available types of logic: either through correlations between timing of institutional changes and changes in the indicators or through direct or indirect causal connections.</p> <p>Results</p> <p>The analysis shows that while biomedical research has certainly contributed to improved health in the United States, other factors have also contributed. In some ways the institutional structure of science-based medicine has worked against creating benefits for some groups in U.S. society.</p> <p>Conclusions</p> <p>The paper concludes with a call for more strategic attention to dimensions of impact other than knowledge outcomes and for participatory planning for research.</p
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