949 resultados para 4 diamino 1


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Human memory is a complex neurocognitive process. By combining psychological and molecular genetics expertise, we examined the APOE ε4 allele, a known risk factor for Alzheimer's disease, and the COMT Val 158 polymorphism, previously implicated in schizophrenia, for association with lowered memory functioning in healthy adults. To assess memory type we used a range of memory tests of both retrospective and prospective memory. Genotypes were determined using RFLP analysis and compared with mean memory scores using univariate ANOVAs. Despite a modest sample size (n=197), our study found a significant effect of the APOE ε4 polymorphism in prospective memory. Supporting our hypothesis, a significant difference was demonstrated between genotype groups for means of the Comprehensive Assessment of Prospective Memory total score (p=0.036; ε4 alleles=1.99; all other alleles=1.86). In addition, we demonstrate a significant interactive effect between the APOE ε4 and COMT polymorphisms in semantic memory. This is the first study to investigate both APOE and COMT genotypes in relation to memory in non-pathological adults and provides important information regarding the effect of genetic determinants on human memory.

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[Extract] For just $5.29 Australians can now purchase "Skins" from local, independent grocers to cover their cigarette packet with the Aboriginal or Torres Strait Islander flag. We argue that this use of cultural content and copyright' imagery on cigarette packets negates health promotion efforts, such as Australia's recent introduction of plain packaging laws and the subsequent dismissal of a legal challenge from the tobacco industry.

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Extracts of Australian plants were screened to detect constituents affecting adenosine di-phosphate (ADP) induced platelet aggregation and [14C]5-hydroxytryptamine (5-HT) release. Extracts of four tested plants including, Eremophila gilesii, Erythrina vespertilio, Cymbopogon ambiguus, and Santalum acuminatum, were found to cause significant inhibition of platelet 5-HT release. Inhibition levels ranged from 56-98%, and was not due to the non-specific effects of protein binding tannins. These extracts, and those we have previously identified as being active, were examined further to determine if they affect epinephrine (EPN), arachidonic acid (A.A) or collagen stimulated platelet aggregation and 5-HT release. Among those extracts investigated, we found that both the methanolic extract of E. vespertilio and the dichloromethane (DCM) extract of C. ambiguus were most potent and caused significant inhibition of platelet activation induced by EPN, A.A and to a lesser extent by collagen. Inhibition of ADP induced platelet 5-HT release by both of these extracts, was dose-dependent, with IC50 values for E. vespertilio and C. ambiguus estimated to be 20.4 microl (1.855 mg/ml) and 8.34 microl (0.758 mg/ml), respectively. Overall, C. ambiguus exhibited most activity and also caused dose-dependent inhibition of A.A induced platelet activation. These results indicate that inhibition may occur specifically at a site within the A.A pathway, and suggest the presence of a cyclo-oxygenase inhibitor. Both E. vespertilio and C. ambiguus are reported to be traditional headache treatments, with the present study providing evidence that they affect 5-HT release.

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A technique for analysing exhaust emission plumes from unmodified locomotives under real world conditions is described and applied to the task of characterizing plumes from railway trains servicing an Australian shipping port. The method utilizes the simultaneous measurement, downwind of the railway line, of the following pollutants; particle number, PM2.5 mass fraction, SO2, NOx and CO2, with the last of these being used as an indicator of fuel combustion. Emission factors are then derived, in terms of number of particles and mass of pollutant emitted per unit mass of fuel consumed. Particle number size distributions are also presented. The practical advantages of the method are discussed including the capacity to routinely collect emission factor data for passing trains and to thereby build up a comprehensive real world database for a wide range of pollutants. Samples from 56 train movements were collected, analyzed and presented. The quantitative results for emission factors are: EF(N)=(1.7±11016 kg-1, EF(PM2.5)= (1.1±0.5) g·kg-1, EF(NOx)= (28±14) g·kg-1, and EF(SO2 )= (1.4±0.4) g·kg-1. The findings are compared with comparable previously published work. Statistically significant (p<α, α=0.05) correlations within the group of locomotives sampled were found between the emission factors for particle number and both SO2 and NOx.

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The interaction between new two-dimensional carbon allotropes, i.e. graphyne (GP) and graphdiyne (GD), and light metal complex hydrides LiAlH4, LiBH4, and NaAlH4 was studied using density functional theory (DFT) incorporating long range van der Waals dispersion correction. The light metal complex hydrides show much stronger interaction with GP and GP than that with fullerene due to the well defined pore structure. Such strong interactions greatly affect the degree of charge donation from the alkali metal atom to AlH4 or BH4, consequently destabilizing the Al-H or B-H bonds. Compared to the isolated light metal complex hydride, the presence of GP or GD can lead to a significant reduction of the hydrogen removal energy. Most interestingly, the hydrogen removal energies for LiBHx on GP and with GD are found to be lowered at all the stages (x from 4 to 1) whereas the H-removal energy in the third stage is increased for LiBH4 on fullerene. In addition, the presence of uniformly distributed pores on GP and GD is expected to facilitate the dehydrogenation of light metal complex hydrides. The present results highlight new interesting materials to catalyze light metal complex hydrides for potential application as media for hydrogen storage. Since GD has been successfully synthesized in a recent experiment, we hope the present work will stimulate further experimental investigations in this direction.

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Loneliness is a distressing, complex, universal phenomena. This review focuses on loneliness in children and adolescents, specifically examining research on the relationship between young people’s social anxiety and loneliness and the role of bullying victimization and loneliness. The three concepts are distinct, yet inextricably intertwined as antecedents and consequences of each other. The constructs are bi-directional, often forming a feedback loop or negative cycle. Implications for interventions are addressed.

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Faced with the perceived need to redefine education for more economic utilitarian purposes, as well as to encourage compliance with government policies, Australia, like many other Anglophone nations, has engaged in numerous policy shifts resulting in performativity practices becoming commonplace in the educational landscape. A series of interviews with teachers from Queensland, Australia, in which they revealed their experiences of professionalism are examined archaeologically to reveal how they enact their roles in response to this performative agenda. Findings suggest that while there is some acceptance amongst teachers of the performative discourse, there is increasing resistance, which permits the construction of alternative or counter-discourses to the currently internationally pervasive performative climate.

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Purpose: It is not known whether it is possible to repeatedly supercompensate muscle glycogen stores after exhaustive exercise bouts undertaken within several days. Methods: We evaluated the effect of repeated exercise-diet manipulation on muscle glycogen and triacylglycerol (IMTG) metabolism and exercise capacity in six well-trained subjects who completed an intermittent, exhaustive cycling protocol (EX) on three occasions separated by 48 h (i.e., days 1, 3, and 5) in a 5-d period. Twenty-four hours before day 1, subjects consumed a moderate (6 g·kg-1)-carbohydrate (CHO) diet, followed by 5 d of a high (12 g·kg-1·d -1)-CHO diet. Muscle biopsies were taken at rest, immediately post-EX on days 1, 3, and 5, and after 3 h of recovery on days 1 and 3. Results: Compared with day 1, resting muscle [glycogen] was elevated on day 3 but not day 5 (435 ± 57 vs 713 ± 60 vs 409 ± 40 mmol·kg -1, P < 0.001). [IMTG] was reduced by 28% (P < 0.05) after EX on day 1, but post-EX levels on days 3 and 5 were similar to rest. EX was enhanced on days 3 and 5 compared with day 1 (31.9 ± 2.5 and 35.4 ± 3.8 vs 24.1 ± 1.4 kJ·kg-1, P < 0.05). Glycogen synthase activity at rest and immediately post-EX was similar between trials. Additionally, the rates of muscle glycogen accumulation were similar during the 3-h recovery period on days 1 and 3. Conclusion: We show that well-trained men cannot repeatedly supercompensate muscle [glycogen] after glycogen-depleting exercise and 2 d of a high-CHO diet, suggesting that the mechanisms responsible for glycogen accumulation are attenuated as a consequence of successive days of glycogen-depleting exercise.

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Early determination of immune status is essential for the prevention and/or amelioration of disease following exposure to chickenpox. This is of particular significance for pregnant women because of the additional risks to the foetus or newborn.1 To determine the usefulness of a self-reported history of chickenpox in adult women in the Top End, we compared it with serological evidence of immunity.

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Objective: Modern series from high-volume esophageal centers report an approximate 40% 5-year survival in patients treated with curative intent and postoperative mortality rates of less than 4%. An objective analysis of factors that underpin current benchmarks within high-volume centers has not been performed. Methods: Three time periods were studied, 1990 to 1998 (period 1), 1999 to 2003 (period 2), and 2004 to 2008 (period 3), in which 471, 254, and 342 patients, respectively, with esophageal cancer were treated with curative intent. All data were prospectively recorded, and staging, pathology, treatment, operative, and oncologic outcomes were compared. Results: Five-year disease-specific survival was 28%, 35%, and 44%, and in-hospital postoperative mortality was 6.7%, 4.4%, and 1.7% for periods 1 to 3, respectively (P < .001). Period 3, compared with periods 1 and 2, respectively, was associated with significantly (P < .001) more early tumors (17% vs 4% and 6%), higher nodal yields (median 22 vs 11 and 18), and a higher R0 rate in surgically treated patients (81% vs 73% and 75%). The use of multimodal therapy increased (P < .05) across time periods. By multivariate analysis, age, T stage, N stage, vascular invasion, R status, and time period were significantly (P < .0001) associated with outcome. Conclusions: Improved survival with localized esophageal cancer in the modern era may reflect an increase of early tumors and optimized staging. Important surgical and pathologic standards, including a higher R0 resection rate and nodal yields, and lower postoperative mortality, were also observed. Copyright © 2012 by The American Association for Thoracic Surgery.

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Antioestrogens are among the most widely used agents in the treatment of breast cancer. There has been a recent surge of interest in these compounds because of their potential breast cancer chemopreventive properties. The newer generation of antioestrogens, with increased selectivity and better toxicity profiles, have the potential to increase the effectiveness of hormonal treatment of breast cancer. The selective oestrogen receptor modulators (SERMs) hold the promise of revolutionising the care of healthy postmenopausal women with their beneficial effects on bone and lipids in addition to the chemoprevention of breast cancer.

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Tumor hypoxia has been recognized to confer resistance to anticancer therapy since the early 20th century. More recently, its fundamental role in tumorigenesis has been established. Hypoxia-inducible factor (HIF)-1 has been identified as an important transcription factor that mediates the cellular response to hypoxia, promoting both cellular survival and apoptosis under different conditions. Increased tumor cell expression of this transcription factor promotes tumor growth In vivo and is associated with a worse prognosis in patients with non-small-cell lung cancer (NSCLC) undergoing tumor resection. The epidermal growth factor receptor (EGFR) promotes tumor cell proliferation and anglogenesis and inhibits apoptosis. Epidermal growth factor receptor expression increases in a stepwise manner during tumorigenesis and is overexpressed in > 50% of NSCLC tumors. This review discusses the reciprocal relationship between tumor cell hypoxia and EGFR. Recent studies suggest that hypoxia induces expression of EGFR and its ligands. In return, EGFR might enhance the cellular response to hypoxia by increasing expression of HIF-1α, and so act as a survival factor for hypoxic cancer cells. Immunohistochemical studies on a series of resected NSCLC tumors add weight to this contention by demonstrating a close association between expression of EGFR, HIF-1α, and:1 of HIF-1's target proteins, carbonic anhydrase IX. In this article we discuss emerging treatment strategies for NSCLC that target HIF-1, HIF-1 transcriptional targets, and EGFR.

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Business process analysis and process mining, particularly within the health care domain, remain under-utilised. Applied research that employs such techniques to routinely collected, health care data enables stakeholders to empirically investigate care as it is delivered by different health providers. However, cross-organisational mining and the comparative analysis of processes present a set of unique challenges in terms of ensuring population and activity comparability, visualising the mined models and interpreting the results. Without addressing these issues, health providers will find it difficult to use process mining insights, and the potential benefits of evidence-based process improvement within health will remain unrealised. In this paper, we present a brief introduction on the nature of health care processes; a review of the process mining in health literature; and a case study conducted to explore and learn how health care data, and cross-organisational comparisons with process mining techniques may be approached. The case study applies process mining techniques to administrative and clinical data for patients who present with chest pain symptoms at one of four public hospitals in South Australia. We demonstrate an approach that provides detailed insights into clinical (quality of patient health) and fiscal (hospital budget) pressures in health care practice. We conclude by discussing the key lessons learned from our experience in conducting business process analysis and process mining based on the data from four different hospitals.

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BACKGROUND Tubulointerstitial lesions, characterized by tubular injury, interstitial fibrosis and the appearance of myofibroblasts, are the strongest predictors of the degree and progression of chronic renal failure. These lesions are typically preceded by macrophage infiltration of the tubulointerstitium, raising the possibility that these inflammatory cells promote progressive renal disease through fibrogenic actions on resident tubulointerstitial cells. The aim of the present study, therefore, was to investigate the potentially fibrogenic mechanisms of interleukin-1beta (IL-1beta), a macrophage-derived pro-inflammatory cytokine, on human proximal tubule cells (PTC). METHODS Confluent, quiescent, passage 2 PTC were established in primary culture from histologically normal segments of human renal cortex (N = 11) and then incubated in serum- and hormone-free media supplemented with either IL-1beta (0 to 4 ng/mL) or vehicle (control). RESULTS IL-1beta significantly enhanced fibronectin secretion by up to fourfold in a time- and concentration-dependent fashion. This was accompanied by significant (2.5- to 6-fold) increases in alpha-smooth muscle actin (alpha-SMA) expression, transforming growth factor beta (TGF-beta1) secretion, nitric oxide (NO) production, NO synthase 2 (NOS2) mRNA and lactate dehydrogenase (LDH) release. Cell proliferation was dose-dependently suppressed by IL-1beta. NG-methyl-l-arginine (L-NMMA; 1 mmol/L), a specific inhibitor of NOS, blocked NO production but did not alter basal or IL-1beta-stimulated fibronectin secretion. In contrast, a pan-specific TGF-beta neutralizing antibody significantly blocked the effects of IL-1beta on PTC fibronectin secretion (IL-1beta, 268.1 +/- 30.6 vs. IL-1beta+alphaTGF-beta 157.9 +/- 14.4%, of control values, P < 0.001) and DNA synthesis (IL-1beta 81.0 +/- 6.7% vs. IL-1beta+alphaTGF-beta 93.4 +/- 2.1%, of control values, P < 0.01). CONCLUSION IL-1beta acts on human PTC to suppress cell proliferation, enhance fibronectin production and promote alpha-smooth muscle actin expression. These actions appear to be mediated by a TGF-beta1 dependent mechanism and are independent of nitric oxide release.

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The principle of common but differentiated responsibility (CBDR) will play a role in the 2020 Climate Regime. This Article starts by examining differential treatment within the international legal order, finding that it is ethically and practically difficult to implement an international climate instrument based on formal equality. There is evidence of state parties accepting differential responsibilities in a number of areas within the international legal order and the embedding of CBDR in the United Nations Framework Convention on Climate Change (UNFCCC), means that that differential commitments will lie at the heart of the 2020 climate regime. The UNFCCC applies the implementation method of differentiation, while the Kyoto Protocol applies both the obligation and implementation method of differentiation. It is suggested that the implementation model will be the differentiation model retained in the 2020 climate agreement. The Parties’ submissions under the Durban Platform are considered in order to gain an understanding of their positions on CBDR. While there are areas of contention including the role of principles in shaping obligations and the ongoing legal status of Annex I and Non-Annex I distinction, there is broad consensus among the parties in favour of differentiation by implementation with developed and major economies undertaking Quantified Emission Limitation and Reduction Objectives (economy wide targets) and developing countries that are not major economies undertaking sectoral targets.