81 resultados para 331.844
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The purpose of this article is twofold : first to provide an overview of the emergence of critical health psychology for those working in the related social and health sciences and as a review of its major developments for health psychology; and second to discuss critically the potential for critical health psychology to contribute to promoting public health with specific reference to the directives espoused by Prilleltensky (2003) and Murray and Campbell (2003). The identification of three philosophical phases of the emergence of critical health psychology is used to examine the directions of the field and the challenges facing critical health psychology in order to contribute to public and global health.
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The risk of vitamin D insufficiency is increased in persons having limited sunlight exposure and dietary vitamin D. Supplementation compliance might be improved with larger doses taken less often, but this may increase the potential for side effects. The objective of the present study was to determine whether a weekly or weekly/monthly regimen of vitamin D supplementation is as effective as daily supplementation without increasing the risk of side effects. Participants were forty-eight healthy adults who were randomly assigned for 3 months to placebo or one of three supplementation regimens: 50 μg/d (2000 IU/d, analysed dose 70 μg/d), 250 μg/week (10 000 IU/week, analysed dose 331 μg/week) or 1250 μg/week (50 000 IU/week, analysed dose 1544 μg/week) for 4 weeks and then 1250 μg/month for 2 months. Daily and weekly doses were equally effective at increasing serum 25-hydroxyvitamin D, which was significantly greater than baseline in all the supplemented groups after 30 d of treatment. Subjects in the 1250 μg treatment group, who had a BMI >26 kg/m2, had a steady increase in urinary Ca in the first 3 weeks of supplementation, and, overall, the relative risk of hypercalciuria was higher in the 1250 μg group than in the placebo group (P= 0·01). Although vitamin D supplementation remains a controversial issue, these data document that supplementing with ≤ 250 μg/week ( ≤ 10 000 IU/week) can improve or maintain vitamin D status in healthy populations without the risk of hypercalciuria, but 24 h urinary Ca excretion should be evaluated in healthy persons receiving vitamin D3 supplementation in weekly single doses of 1250 μg (50 000 IU).
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The influence of different instructional constraints on movement organisation and performance outcomes of the penalty kick (PK) was investigated according to participant age. Sixty penalty takers and twelve goalkeepers from two age groups (under 15 and under 17) performed 300 PKs under five different task conditions, including: no explicit instructional constraints provided (Control); instructional constraints on immobility (IMMOBILE) and mobility (MOBILE) of goalkeepers; and, use of keeper-dependent (DEP) and independent (INDEP) strategies by penalty takers. Every trial was video recorded and digitised using motion analysis techniques. Dependent variables (DVs) were: movement speed of penalty takers and the angles between the goalkeeper's position and the goal line (i.e., diving angle), and between the penalty taker and a line crossing the penalty spot and the centre of the goal (i.e., run up angle). Instructions significantly influenced the way that goalkeepers (higher values in MOBILE relative to Control) and penalty takers (higher values in Control than in DEP) used movement speed during performance, as well as the goalkeepers' movements and diving angle (less pronounced dives in the MOBILE condition compared with INDEP). Results showed how different instructions constrained participant movements during performance, although players' performance efficacy remained constant, reflecting their adaptive variability.
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The present study examined the effect of carbohydrate supplementation on changes in neutrophil counts, and the plasma concentrations of cortisol and myoglobin after intense exercise. Eight well-trained male runners ran on a treadmill for 1 h at 85% maximal oxygen uptake on two separate occasions. In a double-blind cross-over design, subjects consumed either 750 ml of a 10% carbohydrate (CHO) drink or a placebo drink on each occasion. The order of the trials was counter-balanced. Blood was drawn immediately before and after exercise, and 1 h after exercise. Immediately after exercise, neutrophil counts (CHO, 49%; placebo, 65%; P<0.05), plasma concentrations of glucose (CHO, 43%; P<0.05), lactate (CHO, 130%; placebo, 130%; P<0.01), cortisol (CHO, 100%; placebo, 161%; P<0.01), myoglobin (CHO, 194%; placebo, 342%; P<0.01) all increased significantly. One hour post-exercise, plasma myoglobin concentration (CHO, 331%; placebo, 482%; P<0.01) and neutrophil count (CHO, 151%; placebo, 230% P<0.01) both increased further above baseline. CHO significantly attenuated plasma myoglobin concentration and the neutrophil count after exercise (P<0.01), but did not affect plasma cortisol concentration. The effects of CHO on plasma myoglobin concentration may be due to alterations in cytokine synthesis, insulin responses or myoglobin clearance rates from the bloodstream during exercise. Plasma cortisol responses to CHO during exercise may depend on the intensity of exercise, or the amount of CHO consumed. Lastly, cortisol appears to play a minor role in the mobilisation of neutrophils after intense exercise.
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Migraine is a common neurological disorder characterised by debilitating head pain and an assortment of additional symptoms which can include nausea, emesis, photophobia, phonophobia and occasionally visual sensory disturbances. Migraine is a complex disease caused by an interplay between predisposing genetic variants and environmental factors. It affects approximately 12 % of studied Caucasian populations with affected individuals being predominantly female. Genes involved in neurological, vascular or hormonal pathways have all been implicated in predisposition towards developing migraine. All of these are nuclear encoded genes, but given the role of mitochondria in a number of neurological disorders and in energy production it is possible that mitochondrial variants may play a role in the pathogenesis of this disease. Mitochondrial DNA has been a useful tool for studying population genetics and human genetic diseases due to the clear inheritance shown through successive generations. Given the clear gender bias found in migraine patients it may be important to investigate X-linked inheritance and mitochondrial-related variants in this disorder. This paper explores the possibility that mitochondrial DNA changes may play a role in migraine. Few variants in the mitochondrial genome have so far been investigated in migraine and new studies should be aimed towards investigating the role of mitochondrial DNA in this common disorder.
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Understanding the evolutionary history and phylogenetic relationships between rare and common species is necessary for the effective management of rare species. The genus Cherax, a group of freshwater crayfish species, is of interest in this regard as a number of species are rare or have restricted distributions while other species are common and widespread. Here we describe the characterisation of three novel nuclear genes of the haemocyanin superfamily for phylogenetic reconstruction of the genus. All novel markers developed in this study amplified consistently in species from three divergent clades of the genus Cherax. The level of polymorphism found in these markers was consistently higher than that found in other nuclear genes previously used in invertebrate systematics, such as NaK ATP-ase. In combination, these markers will be useful to delineate phylogenetic relationships between rare and common Cherax species.
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Background: Multiple sclerosis (MS) is the most common cause of chronic neurologic disability beginning in early to middle adult life. Results from recent genome-wide association studies (GWAS) have substantially lengthened the list of disease loci and provide convincing evidence supporting a multifactorial and polygenic model of inheritance. Nevertheless, the knowledge of MS genetics remains incomplete, with many risk alleles still to be revealed. Methods: We used a discovery GWAS dataset (8,844 samples, 2,124 cases and 6,720 controls) and a multi-step logistic regression protocol to identify novel genetic associations. The emerging genetic profile included 350 independent markers and was used to calculate and estimate the cumulative genetic risk in an independent validation dataset (3,606 samples). Analysis of covariance (ANCOVA) was implemented to compare clinical characteristics of individuals with various degrees of genetic risk. Gene ontology and pathway enrichment analysis was done using the DAVID functional annotation tool, the GO Tree Machine, and the Pathway-Express profiling tool. Results: In the discovery dataset, the median cumulative genetic risk (P-Hat) was 0.903 and 0.007 in the case and control groups, respectively, together with 79.9% classification sensitivity and 95.8% specificity. The identified profile shows a significant enrichment of genes involved in the immune response, cell adhesion, cell communication/ signaling, nervous system development, and neuronal signaling, including ionotropic glutamate receptors, which have been implicated in the pathological mechanism driving neurodegeneration. In the validation dataset, the median cumulative genetic risk was 0.59 and 0.32 in the case and control groups, respectively, with classification sensitivity 62.3% and specificity 75.9%. No differences in disease progression or T2-lesion volumes were observed among four levels of predicted genetic risk groups (high, medium, low, misclassified). On the other hand, a significant difference (F = 2.75, P = 0.04) was detected for age of disease onset between the affected misclassified as controls (mean = 36 years) and the other three groups (high, 33.5 years; medium, 33.4 years; low, 33.1 years). Conclusions: The results are consistent with the polygenic model of inheritance. The cumulative genetic risk established using currently available genome-wide association data provides important insights into disease heterogeneity and completeness of current knowledge in MS genetics.
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Former refugees have been resettled in Australia since the 1940’s through the Humanitarian Migration Stream. This chapter highlights the impact of forced migration and the refugee experience of trauma on survival. The journey from pre-migration crises, to the process of fleeing one’s country, through to the challenges associated with resettlement, can have a significant impact on the mental health of Humanitarian Entrants to Australia. Differences in culture can have an impact on the meaning constructed from these experiences, and on help-seeking behaviour and preferred methods of intervention. To date, Western mental health services have used an understanding of trauma based on pathology and largely individualist intervention techniques. In this chapter, however, we seek to understand the experience of trauma for former refugees from a salutogenic perspective, and acknowledge community based coping methods and the strengths and resilience of former refugees. Using the construct of posttraumatic growth, adaptive factors of strength, religion, compassion, and new possibilities are identified as relevant to African Humanitarian Entrants in Australia.
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Background The novel breast cancer metastasis modulator gene signal-induced proliferation-associated 1 (Sipa1) underlies the breast cancer metastasis efficiency modifier locus Mtes 1 and has been shown to influence mammary tumour metastatic efficiency in the mouse, with an ectopically expressing Sipa1 cell line developing 1.5 to 2 fold more surface pulmonary metastases. Sipa1 encodes a mitogen-inducible GTPase activating (GAP) protein for members of the Ras-related proteins; participates in cell adhesion and modulates mitogen-induced cell cycle progression. Germline SIPA1 SNPs showed association with positive lymph node metastasis and hormonal receptor status in a Caucasian cohort. We hypothesized that SIPA1 may also be correlated to breast carcinoma incidence as well as prognosis. Therefore, this study investigated the potential relationship of SIPA1 and human breast cancer incidence by a germline SNP genotype frequency association study in a case-control Caucasian cohort in Queensland, Australia. Methods The SNPs genotyped in this study were identified in a previous study and the genotyping assays were carried out using TaqMan SNP Genotyping Assays. The data were analysed with chi-square method and the Monte Carlo style CLUMP analysis program. Results Results indicated significance with SIPA1 SNP rs3741378; the CC genotype was more frequently observed in the breast cancer group compared to the disease-free control group, indicating the variant C allele was associated with increased breast cancer incidence. Conclusion This observation indicates SNP rs3741378 as a novel potential sporadic breast cancer predisposition SNP. While it showed association with hormonal receptor status in breast cancer group in a previous pilot study, this exonic missense SNP (Ser (S) to Phe (F)) changes a hydrophilic residue (S) to a hydrophobic residue (F) and may significantly alter the protein functions of SIPA1 in breast tumourgenesis. SIPA1 SNPs rs931127 (5' near gene), and rs746429 (synonymous (Ala (A) to Ala (A)), did not show significant associations with breast cancer incidence, yet were associated with lymph node metastasis in the previous study. This suggests that SIPA1 may be involved in different stages of breast carcinogenesis and since this study replicates a previous study of the associated SNP, it implicates variants of the SIPA1 gene as playing a potential role in breast cancer.
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Migraine is a complex familial condition that imparts a significant burden on society. There is evidence for a role of genetic factors in migraine, and elucidating the genetic basis of this disabling condition remains the focus of much research. In this review we discuss results of genetic studies to date, from the discovery of the role of neural ion channel gene mutations in familial hemiplegic migraine (FHM) to linkage analyses and candidate gene studies in the more common forms of migraine. The success of FHM regarding discovery of genetic defects associated with the disorder remains elusive in common migraine, and causative genes have not yet been identified. Thus we suggest additional approaches for analysing the genetic basis of this disorder. The continuing search for migraine genes may aid in a greater understanding of the mechanisms that underlie the disorder and potentially lead to significant diagnostic and therapeutic applications.
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Multiple sclerosis (MS) is a chronic neurological disease characterized by central nervous system (CNS) inflammation and demyelination. The C677T substitution variant in the methylenetetrahydrofolate reductase (MTHFR) gene has been associated with increased levels of circulating homocysteine and is a mild risk factor for vascular disease. Higher blood levels of homocysteine have also been reported in MS. Thus, the C677T mutation of the MTHFR gene may influence MS susceptibility. Noradrenaline, a neurotransmitter believed to play an immunosupressive role in neuroinflammatory disorders, is catabolized by catechol-O-methyl transferase (COMT). The COMT G158A substitution results in a three- to four-fold decreased activity of the COMT enzyme, which may influence CNS synaptic catecholamine breakdown and could also play a role in MS inflammation. We tested DNA from Australian MS patients and unaffected control subjects, matched for gender, age and ethnicity. Specifically, we genotyped the MTHFR C677T and the COMT G158A mutations. Genotype distributions showed that the homozygous mutant MTHFR genotype (T/T) and the COMT (H/H) genotype were slightly over-represented in the MS group (16% versus 11% and 24% versus 19%, respectively), but both variations failed to reach statistical significance (P=0.15 and P=0.32, respectively). Hence, results from the present study do not support a major role for either functional gene mutation in MS susceptibility.
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Industry-school partnerships (ISPs) are increasingly being recognised as a new way of providing vocational education opportunities. However, there is limited research investigating their impact on school to work transitions. This paper reports on a government-led ISP, the Gateway to Industry Schools Program, established in Queensland, Australia. Central to this initiative is the Queensland Minerals and Energy Academy (QMEA), a lead organisation for 28 schools and 17 multi-national sponsor companies. This research adopted a qualitative case study methodology and draws upon boundary crossing theory as means to understand a Minerals and Energy ISP. We distinguish four types of boundary crossing mechanisms, which align with principles for effectiveness in ISPs. The main findings were that boundary crossing mechanisms assist ISPs to develop industry-based contextualised curriculum and to prepare school students for employment.
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Traumatic experiences can have a powerful impact on individuals and communities but the relationship between perceptions of beneficial and pathological outcomes are not known. Therefore, this meta-analysis examined both the strength and the linearity of the relationship between symptoms of posttraumatic stress disorder (PTSD) and perceptions of posttraumatic growth (PTG) as well as identifying the potential moderating roles of trauma type and age. Literature searches of all languages were conducted using the ProQuest, Wiley Interscience, ScienceDirect, Informaworld and Web of Science databases. Linear and quadratic (curvilinear) rs as well as βs were analysed. Forty-two studies (N=11, 469) that examined both PTG and symptoms of PTSD were included in meta-analytic calculations. The combined studies yielded a significant linear relationship between PTG and PTSD symptoms (r=.315, CI = 0.299, 0.331), but also a significantly stronger (as tested by Fisher’s transformation) curvilinear relationship (r=.372, CI = 0.353, 0.391). The strength and linearity of these relationships differed according to trauma type and age. The results remind those working with traumatised people that positive and negative post-trauma outcomes can co-occur. A focus only on PTSD symptoms only may limit or slow recovery and mask the potential for growth.
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Layers (about 60-100 μm thick) of almost pure BaCuO2 (BC1), as determined using X-ray diffractometry (XRD) and scanning electron microscopy (SEM), coat the surfaces of YBa2Cu3O7-x (Y123) samples partial melt processed using a single-zone vertical furnace. The actual Cu/Ba ratio of the BC1 phase is 1.2-1.3 as determined using energy dispersive X-ray spectrometry (EDS). The nominally BC1 phase displays an exsolution of BC1.5 or BC2 in the form of thin plates (about 50-100 nm thick) along {100}-type cleavage planes or facets. The exsolved phase also fills cracks within the BC1 layer that require it to be in a molten state at some stage of processing. The samples were influenced by Pt contamination from the supporting wire, which may have stabilised the BC1.5 phase. Many of the Y123 grains have the same morphology as the exsolution domains, and run nearly parallel to the thin plates of the exsolved phases, strongly indicating that Y123 nucleation took place at the interface between the BC1 and the BC1.5 or BC2 exsolved phases. The network of nearly parallel exsolved 'channels' provides a matrix and a mechanism through which a high degree of local texture can be initiated in the material.