977 resultados para American Society of Biological Chemists


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New-onset diabetes after transplantation is a common complication that reduces recipient survival. Research in renal transplant recipients has suggested that pancreatic ß-cell dysfunction, as opposed to insulin resistance, may be the key pathologic process. In this study, clinical and genetic factors associated with new-onset diabetes after transplantation were identified in a white population. A joint analysis approach, with an initial genome-wide association study in a subset of cases followed by de novo genotyping in the complete case cohort, was implemented to identify single-nucleotide polymorphisms (SNPs) associated with the development of new-onset diabetes after transplantation. Clinical variables associated with the development of diabetes after renal transplantation included older recipient age, female sex, and percentage weight gain within 12 months of transplantation. The genome-wide association study identified 26 SNPs associated with new-onset diabetes after transplantation; this association was validated for eight SNPs (rs10484821, rs7533125, rs2861484, rs11580170, rs2020902, rs1836882, rs198372, and rs4394754) by de novo genotyping. These associations remained significant after multivariate adjustment for clinical variables. Seven of these SNPs are associated with genes implicated in ß-cell apoptosis. These results corroborate recent clinical evidence implicating ß-cell dysfunction in the pathophysiology of new-onset diabetes after transplantation and support the pursuit of therapeutic strategies to protect ß cells in the post-transplant period.

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Geo-synthetic reinforcements are often used to enhance the stability of geotechnical structures such as embankments. These geosynthetic polymers often show significant creep deformational behaviour. In the short-term performance of a geotechnical structure, it may not play a significant role. However, while dealing with the long term behaviour, it is necessary to investigate its effect. In this paper two plane strain fully coupled finite element analysis have been conducted; one with and the other without taking into account of the creep behaviour of geosynthetics. A well documented field case of Leneghans embankment (Geogrid improved wide embankment constructed near Sydney, Australia in 1990s) have been used for this purpose. It is evident from the analyses that though the geosynthetic reinforcements may play a vital role in the performance/stability of an embankment in the early days (during and after construction), its contribution may become insignificant with time and the creep of geo-synthetic may not play a significant role in the long term stability. © 2012 American Society of Civil Engineers.

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Breast augmentation for cosmetic purposes is an increasingly common procedure in the USA and UK. In the USA in 2003, a total of 254 140 breast augmentation procedures were carried out [American Society of Plastic Surgeons, http://www.plasticsurgery.org/newsroom/ Procedural-Statistics-Press-Kit-Index.cfm9-1-2005; 2006.(1)]. It has been previously estimated that between 1 and 1.5 million women in the USA have prosthetic breast implants [Cook RR, Delongchamp RR, Woodbury M, et at. The prevalence of women with breast implants in the United States, 1989. J Clin Epidemiol 1995;48:519-25.(2)]. The UK National Breast Implant Registry has recorded a rise in the numbers of women receiving breast implants, with over 13 000 procedures registered in 2001; an estimated 77% of these were for cosmetic purposes. No association has been found between the presence of breast implants in a breast and an increased risk of breast cancer, and this subject has been comprehensively reviewed elsewhere [Hoshaw SJ, Klein PJ, Clark BD, et al. Breast implants and cancer: causation, delayed detection, and survival. Plast Reconstr Surg 2001; 107:1393-407.(3)]. However, as the population of women with breast implants ages, an increasing number of them will develop breast cancer; a reflection of the fact that the incidence of the disease increases with increasing age. Debate continues on the effect of breast implants on the efficacy of mammography in diagnosing breast cancer, and the role of other imaging techniques for this purpose, as well as the limitations that the presence of implants place on percutaneous biopsy techniques. We review the Literature on the radiological and tissue diagnosis of breast cancer in women with a history of previous augmentation mammaplasty. (c) 2007 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

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Death Receptor 5 (DR5) is a pro-apoptotic cell-surface receptor that is a potential therapeutic target in cancer. Despite the potency of DR5-targeting agents in preclinical models, the translation of these effects into the clinic remains disappointing. Herein, we report an alternative approach to exploiting DR5 tumor expression using antibody-targeted, chemotherapy-loaded nanoparticles. We describe the development of an optimized polymer-based nanotherapeutic incorporating both a functionalized polyethylene glycol (PEG) layer and targeting antibodies to limit premature phagocytic clearance whilst enabling targeting of DR5-expressing tumor cells. Using the HCT116 colorectal cancer model, we show that following binding to DR5, the nanoparticles activate caspase 8, enhancing the anti-tumor activity of the camptothecin payload both in vitro and in vivo. Importantly, the combination of nanoparticle-induced DR5 clustering with camptothecin delivery overcomes resistance to DR5-induced apoptosis caused by loss of BAX or overexpression of anti-apoptotic FLIP. This novel approach may improve the clinical activity of DR5-targeted therapeutics while increasing tumor-specific delivery of systemically toxic chemotherapeutics.Molecular Therapy (2014); doi:10.1038/mt.2014.137.

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Several theories of legislative organisation have been proposed to explain committee selection in American legislatures, but do these theories travel outside the United States? This paper tests whether these theories apply to data from the Canadian House of Commons. It was found that the distributive and partisan models of legislative organisation explain committee composition in Canada. In many cases, committees in the House of Commons are made up of preference outliers. As predicted by partisan models, it was also found that the governing party stacks committees with its members, but this is conditional upon the strength of the governing party.

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A large body of empirical research shows that psychosocial risk factors (PSRFs) such as low socio-economic status, social isolation, stress, type-D personality, depression and anxiety increase the risk of incident coronary heart disease (CHD) and also contribute to poorer health-related quality of life (HRQoL) and prognosis in patients with established CHD. PSRFs may also act as barriers to lifestyle changes and treatment adherence and may moderate the effects of cardiac rehabilitation (CR). Furthermore, there appears to be a bidirectional interaction between PSRFs and the cardiovascular system. Stress, anxiety and depression affect the cardiovascular system through immune, neuroendocrine and behavioural pathways. In turn, CHD and its associated treatments may lead to distress in patients, including anxiety and depression. In clinical practice, PSRFs can be assessed with single-item screening questions, standardised questionnaires, or structured clinical interviews. Psychotherapy and medication can be considered to alleviate any PSRF-related symptoms and to enhance HRQoL, but the evidence for a definite beneficial effect on cardiac endpoints is inconclusive. A multimodal behavioural intervention, integrating counselling for PSRFs and coping with illness should be included within comprehensive CR. Patients with clinically significant symptoms of distress should be referred for psychological counselling or psychologically focused interventions and/or psychopharmacological treatment. To conclude, the success of CR may critically depend on the interdependence of the body and mind and this interaction needs to be reflected through the assessment and management of PSRFs in line with robust scientific evidence, by trained staff, integrated within the core CR team.

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These guidelines provide a practical and evidence-based resource for the management of patients with Barrett's oesophagus and related early neoplasia. The Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument was followed to provide a methodological strategy for the guideline development. A systematic review of the literature was performed for English language articles published up until December 2012 in order to address controversial issues in Barrett's oesophagus including definition, screening and diagnosis, surveillance, pathological grading for dysplasia, management of dysplasia, and early cancer including training requirements. The rigour and quality of the studies was evaluated using the SIGN checklist system. Recommendations on each topic were scored by each author using a five-tier system (A+, strong agreement, to D+, strongly disagree). Statements that failed to reach substantial agreement among authors, defined as >80% agreement (A or A+), were revisited and modified until substantial agreement (>80%) was reached. In formulating these guidelines, we took into consideration benefits and risks for the population and national health system, as well as patient perspectives. For the first time, we have suggested stratification of patients according to their estimated cancer risk based on clinical and histopathological criteria. In order to improve communication between clinicians, we recommend the use of minimum datasets for reporting endoscopic and pathological findings. We advocate endoscopic therapy for high-grade dysplasia and early cancer, which should be performed in high-volume centres. We hope that these guidelines will standardise and improve management for patients with Barrett's oesophagus and related neoplasia.