415 research outputs found

    Some geochemical constraints upon models for the crystallization of the upper critical zone-main zone interval, northwestern Bushveld complex

    Get PDF
    Ratios between elements Mg, Fe, Co, Cr, Ni, V, and Sc are consistently different in mafic rocks of the upper critical zone, and those above the Bastard unit. Within the 300 m section above the Merensky Reef, 87Sr/86Sr ratios increase from c.0.7063 to c.0.7087, irrespective of rock type. Decoupling of Mg/(Mg + Fe2+) ratios and the Ca contents of plagioclase, and wide variations in the proportions of anorthosite within the Bastard, Merensky, and Merensky Footwall units, are inconsistent with anorthosite formation by simple fractional crystallization of magma batches of limited volume

    The association between dietary patterns and mental health in early adolescence

    Get PDF
    Objective: To investigate the associations between dietary patterns and mental health in early adolescence. Method: The Western Australian Pregnancy Cohort (Raine) Study is a prospective study of 2900 pregnancies recruited from 1989-1992. At 14 years of age (2003-2006; n = 1324), the Child Behaviour Checklist (CBCL) was used to assess behaviour (characterising mental health status), with higher scores representing poorer behaviour. Two dietary patterns (Western and Healthy) were identified using factor analysis and food group intakes estimated by a 212-item food frequency questionnaire. Relationships between dietary patterns, food group intakes and behaviour were examined using general linear modelling following adjustment for potential confounding factors at age 14: total energy intake, body mass index, physical activity, screen use, family structure, income and functioning, gender and maternal education at pregnancy. Results: Higher total (b = 2.20, 95% CI = 1.06, 3.35), internalizing (withdrawn/depressed) (b = 1.25, 95% CI = 0.15, 2.35) and externalizing (delinquent/aggressive) (b = 2.60, 95% CI = 1.51, 3.68) CBCL scores were significantly associated with the Western dietary pattern, with increased intakes of takeaway foods, confectionary and red meat. Improved behavioural scores were significantly associated with higher intakes of leafy green vegetables and fresh fruit (components of the Healthy pattern). Conclusion: These findings implicate a Western dietary pattern in poorer behavioural outcomes for adolescents. Better behavioural outcomes were associated with a higher intake of fresh fruit and leafy green vegetables

    The Dutch multidisciplinary guideline osteoporosis and fracture prevention, taking a local guideline to the international arena

    Get PDF
    Background: In 2018, a grant was provided for an evidence-based guideline on osteoporosis and fracture prevention based on 10 clinically relevant questions. Methods: A multidisciplinary working group was formed with delegates from Dutch scientific and professional societies, including representatives from the patient’s organization and the Dutch Institute for Medical Knowledge. The purpose was to obtain a broad consensus among all participating societies to facilitate the implementation of the updated guideline. Results: Novel recommendations in our guideline are as follows: - In patients with an indication for DXA of the lumbar spine and hips, there is also an indication for VFA. - Directly starting with anabolic drugs (teriparatide or romosozumab) in patients with a very high fracture risk; - Directly starting with zoledronic acid in patients 75 years and over with a hip fracture (independent of DXA); - Directly starting with parenteral drugs (denosumab, teriparatide, zoledronic acid) in glucocorticoid-induced osteoporosis with very high fracture risk; - A lifelong fracture risk management, including lifestyle, is indicated from the start of the first treatment. Conclusion: In our new multidisciplinary guideline osteoporosis and fracture prevention, we developed 5 “relatively new statements” that are all a crucial step forward in the optimization of diagnosis and treatment for fracture prevention. We also developed 5 flowcharts, and we suppose that this may be helpful for individual doctors and their patients in daily practice and may facilitate implementation.</p

    The homocysteine controversy

    Get PDF
    Mild to moderate hyperhomocysteinemia has been identified as a strong predictor of cardiovascular disease, independent from classical atherothrombotic risk factors. In the last decade, a number of large intervention trials using B vitamins have been performed and have shown no benefit of homocysteine-lowering therapy in high-risk patients. In addition, Mendelian randomization studies failed to convincingly demonstrate that a genetic polymorphism commonly associated with higher homocysteine levels (methylenetetrahydrofolate reductase 677 C>T) is a risk factor for cardiovascular disease. Together, these findings have cast doubt on the role of homocysteine in cardiovascular disease pathogenesis, and the homocysteine hypothesis has turned into a homocysteine controversy. In this review, we attempt to find solutions to this controversy. First, we explain that the Mendelian randomization analyses have limitations that preclude final conclusions. Second, several characteristics of intervention trials limit interpretation and generalizability of their results. Finally, the possibility that homocysteine lowering is in itself beneficial but is offset by adverse side effects of B vitamins on atherosclerosis deserves serious attention. As we explain, such side effects may relate to direct adverse effects of the B-vitamin regimen (in particular, the use of high-dose folic acid) or to proinflammatory and proproliferative effects of B vitamins on advanced atherosclerotic lesions

    Lifecourse Childhood Adiposity Trajectories Associated With Adolescent Insulin Resistance

    Get PDF
    OBJECTIVE In the light of the obesity epidemic, we aimed to characterize novel childhood adiposity trajectories from birth to age 14 years and to determine their relation to adolescent insulin resistance. RESEARCH DESIGN ANDMETHODS A total of 1,197 Australian children with cardiovascular/ metabolic proiling at age 14 years were studied serially from birth to age 14 years.Semiparametric mixture modeling was applied to anthropometric data over eight time points to generate adiposity trajectories of z scores (weight-for-height and BMI). Fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR) were compared at age 14 years between adiposity trajectories. RESULTS Seven adiposity trajectories were identified. Three (two rising and one chronic high adiposity) trajectories comprised 32% of the population and were associated with significantly higher fasting insulin and HOMA-IR compared with a reference trajectory group (with longitudinal adiposity z scores of approximately zero). There was a significant sex by trajectory group interaction (P,0.001). Girls within a rising trajectory fromlow tomoderate adiposity did not show increased insulin resistance. Maternal obesity, excessive weight gain during pregnancy,and gestational diabetes were more prevalent in the chronic high adiposity trajectory. CONCLUSIONS A range of childhood adiposity trajectories exist. The greatest insulin resistance at age 14 years is seen in those with increasing trajectories regardless of birth weight and in high birth weight infants whose adiposity remains high. Public health professionals should urgently target both excessive weight gain in early childhood across all birth weights and maternal obesity and excessive weight gain during pregnancy

    Afrikaans adaptation of the children’s hope scale: Validation and measurement invariance

    Get PDF
    The overarching aim of this study was to validate the Afrikaans version of Snyder’s (1997) Children’s Hope Scale in a sample of children from Cape Town, South Africa. Within this process, the study aimed to test the measurement invariance across the English and Afrikaans language versions. The study used a cross-sectional survey design, with a two-stage stratified random sample of 1022 children between the ages of 11- to 12-years-old. We selected the participants from 15 schools located in low and middle socio-economic status communities in the Cape Town Metropole. We used confirmatory factor analysis to analyse the data. The results indicated a good fit for the overall model using the pooled sample (X2 = 35.692; df = 7; p =.00; CFI =.984; RMSEA =.063; SRMR =.023). Multi-group confirmatory factor analysis further demonstrated the tenability of metric and scalar invariance

    Authentic leadership, followership, and psychological capital as antecedents of work engagement

    Get PDF
    The present study investigated authentic leadership, psychological capital, and followership behaviour influences on work engagement of employees . Respondents were 901 South African employees within the healthcare industry organisation (n = 647) and mining industry (n = 254) . The employees completed questionnaires on authentic leadership, psychological capital, and followership behaviour, and work engagement . Results following structural equation modelling and mediation analysis suggest work engagement to be explained by the psychological capital of the employee rather than by authentic leadership qualities . Improving employee psychological capital has the potential to enhance the levels of work engagement of employees

    Towards the clinical implementation of pharmacogenetics in bipolar disorder.

    Get PDF
    BackgroundBipolar disorder (BD) is a psychiatric illness defined by pathological alterations between the mood states of mania and depression, causing disability, imposing healthcare costs and elevating the risk of suicide. Although effective treatments for BD exist, variability in outcomes leads to a large number of treatment failures, typically followed by a trial and error process of medication switches that can take years. Pharmacogenetic testing (PGT), by tailoring drug choice to an individual, may personalize and expedite treatment so as to identify more rapidly medications well suited to individual BD patients.DiscussionA number of associations have been made in BD between medication response phenotypes and specific genetic markers. However, to date clinical adoption of PGT has been limited, often citing questions that must be answered before it can be widely utilized. These include: What are the requirements of supporting evidence? How large is a clinically relevant effect? What degree of specificity and sensitivity are required? Does a given marker influence decision making and have clinical utility? In many cases, the answers to these questions remain unknown, and ultimately, the question of whether PGT is valid and useful must be determined empirically. Towards this aim, we have reviewed the literature and selected drug-genotype associations with the strongest evidence for utility in BD.SummaryBased upon these findings, we propose a preliminary panel for use in PGT, and a method by which the results of a PGT panel can be integrated for clinical interpretation. Finally, we argue that based on the sufficiency of accumulated evidence, PGT implementation studies are now warranted. We propose and discuss the design for a randomized clinical trial to test the use of PGT in the treatment of BD
    corecore