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Barrett's esophagus (BE) is the precursor to esophageal adenocarcinoma (EAC). Progression to cancer typically occurs in a stepwise fashion through worsening dysplasia and ultimately, invasive neoplasia. Established EAC with deep involvement of the esophageal wall and/or metastatic disease is invariably associated with poor long-term survival rates. This guides the rationale of surveillance of Barrett’s in an attempt to treat lesions at an earlier, and potentially curative stage. The last two decades have seen a paradigm shift in management of Barrett’s with rapid expansion in the role of endoscopic eradication therapy (EET) for management of dysplastic and early neoplastic BE, and there have been substantial changes to international consensus guidelines for management of early BE based on evolving evidence. This review aims to assist the physician in the therapeutic decision-making process with patients by comprehensive review and summary of literature surrounding natural history of Barrett’s by histological stage, and the effectiveness of interventions in attenuating the risk posed by its natural history. Key findings were as follows. Non-dysplastic Barrett’s is associated with extremely low risk of progression, and interventions cannot be justified. The annual risk of cancer progression in low grade dysplasia is between 1%-3%; EET can be offered though evidence for its benefit remains confined to highly select settings. High-grade dysplasia progresses to cancer in 5%-10% per year; EET is similarly effective to and less morbid than surgery and should be routinely performed for this indication. Risk of nodal metastases in intramucosal cancer is 2%-4%, which is comparable to operative mortality rate, so EET is usually preferred. Submucosal cancer is associated with nodal metastases in 14%-41% hence surgery remains standard of care, except for select situations.  相似文献   
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The management of distal humeral fractures in adults presents a unique set of challenges. Almost always they necessitate operative management, which might include complex intra-articular fracture fixation of very comminuted free fragments in an already complex joint, or, increasingly, novel arthroplasty techniques. Clinicians managing these injuries must be confident that they possess the requisite skills set, and, in the UK at least, this in itself is under scrutiny. This summary aims to acquaint the reader with the basic knowledge sufficient to begin to understand the approaches to managing these injuries, and some of the decision-making difficulties that are encountered.  相似文献   
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Tuberculosis is a severe disease affecting millions worldwide. Unfortunately, treatment strategies are hampered both by the prohibitively long treatment regimen and the rise of drug-resistant strains. Significant effort has been expended in the search for new treatments, but few options have successfully emerged, and new treatment modalities are desperately needed. Recently, there has been growing interest in the synergistic antibacterial effects of copper ions (CuII/I) in combination with certain small molecular compounds, and we have previously reported development of a drug screening strategy to harness the intrinsic bactericidal properties of CuII/I. Here, we describe the copper-dependent antimycobacterial properties of disulfiram, an FDA-approved and well-tolerated sobriety aid. Disulfiram was inhibitory to mycobacteria only in the presence of CuII/I and exerted its bactericidal activity well below the active concentration of CuII/I or disulfiram alone. No other physiologically relevant bivalent transition metals (e.g., FeII, NiII, MnII, and CoII) exhibited this effect. We demonstrate that the movement of the disulfiram-copper complex across the cell envelope is porin independent and can inhibit intracellular protein functions. Additionally, the complex is able to synergistically induce intracellular copper stress responses significantly more than CuII/I alone. Our data suggest that by complexing with disulfiram, CuII/I is likely allowed unfettered access to vulnerable intracellular components, bypassing the normally sufficient copper homeostatic machinery. Overall, the synergistic antibacterial activity of CuII/I and disulfiram reveals the susceptibility of the copper homeostasis system of Mycobacterium tuberculosis to chemical attacks and establishes compounds that act in concert with copper as a new class of bacterial inhibitors.  相似文献   
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European Child & Adolescent Psychiatry - The majority of adolescents with mental health problems do not experience continuity of care when they reach the transition boundary of their child and...  相似文献   
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European Child & Adolescent Psychiatry - Suicidality in the child and adolescent population is a major public health concern. There is, however, a lack of developmentally sensitive valid and...  相似文献   
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Pectinases are a group of enzymes, which catalyze the breakdown of pectin with numerous applications in various industries. Microbes are the predominant pectinase producers. In the present study, bacterial species were isolated from the soil of a vegetable and fruit dump yard area in a market. The species screened and isolated were identified as Bacillus tequilensis SALBT, and the media and culture conditions were optimized for enhanced production of total pectinases. Maximum pectinolytic activity was observed with 1.5% (w/v) pectin concentration with a combination of yeast extract as nitrogen source and MgSO4 as a metal ion source. Carbon/nitrogen in 2:1 ratio (w/v) yielded the maximum pectinase production with pH and temperature of the medium of 7.5°C and 40°C, respectively. Pectinase activity was determined by the dinitrosalicylic acid method. The pectinase production was relatively stable in the presence of various surfactants like Tween (20, 40, 60, and 80) and sodium dodecyl sulfate (SDS), whereas Triton X‐100 showed an inhibitory effect. Mass production of the enzyme in optimized media and partial purification was performed by ammonium sulfate precipitation followed by dialysis. The approximate molecular weight of the partially purified pectinase was found to be 35 kDa by SDS‐polyacrylamide gel electrophoresis. Application studies such as demucilaging coffee beans and juice clarification were also performed. The findings revealed that B. tequilensis SALBT with pectinase activity has the ability to remove the mucilage layer of pulped coffee seeds, and the partially purified pectinases found to be effective in clarifying juice.  相似文献   
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