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With the advent of transcatheter aortic valve implantation (TAVI) techniques, a renewed interest has developed in sutureless aortic valve concepts in the last decade. The main feature of sutureless aortic valve implantation is the speed of insertion, thus making implantation easier for the surgeon. As a result, cross clamp times and myocardial ischemia may be reduced. The combined procedures (CABG with AVR in particular) can be done with a short cross clamp time. Perceval valve also provides an increased effective orifice area as compared with a stented bioprosthesis. Sutureless implantation of the Perceval valve is not only associated with shorter cross-clamp and cardiopulmonary bypass times but improved clinical outcomes too. This review covers the sutureless aortic valves and their evolution, with elaborate details on Perceval S valve in particular (which is the most widely used sutureless valve around the globe).  相似文献   
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ObjectiveTo determine the effectiveness of telemedicine in the delivery of diabetes care in low- and middle-income countries.MethodsWe searched seven databases up to July 2020 for randomized controlled trials investigating the effectiveness of telemedicine in the delivery of diabetes care in low- and middle-income countries. We extracted data on the study characteristics, primary end-points and effect sizes of outcomes. Using random effects analyses, we ran a series of meta-analyses for both biochemical outcomes and related patient properties.FindingsWe included 31 interventions in our meta-analysis. We observed significant standardized mean differences of −0.38 for glycated haemoglobin (95% confidence interval, CI: −0.52 to −0.23; I2 = 86.70%), −0.20 for fasting blood sugar (95% CI: −0.32 to −0.08; I2 = 64.28%), 0.81 for adherence to treatment (95% CI: 0.19 to 1.42; I2 = 93.75%), 0.55 for diabetes knowledge (95% CI: −0.10 to 1.20; I2 = 92.65%) and 1.68 for self-efficacy (95% CI: 1.06 to 2.30; I2 = 97.15%). We observed no significant treatment effects for other outcomes, with standardized mean differences of −0.04 for body mass index (95% CI: −0.13 to 0.05; I2 = 35.94%), −0.06 for total cholesterol (95% CI: −0.16 to 0.04; I2 = 59.93%) and −0.02 for triglycerides (95% CI: −0.12 to 0.09; I2 = 0%). Interventions via telephone and short message service yielded the highest treatment effects compared with services based on telemetry and smartphone applications.ConclusionAlthough we determined that telemedicine is effective in improving several diabetes-related outcomes, the certainty of evidence was very low due to substantial heterogeneity and risk of bias.  相似文献   
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Although hepatic ischemia-reperfusion (IR) injury is partially mediated by tumor necrosis factor-alpha (TNF), we recently found that low-dose TNF before IR is hepatoprotective. We examined the seemingly conflicting roles of TNF in mediating liver injury in a partial hepatic IR model using TNF gene knockout (TNF ko) mice to allow TNF replacement at specified times. Compared with wild-type mice, TNF ko mice exhibit minimal alanine aminotransferase release and few hepatonecrotic lesions during the early (time, 2 hours) and late (time, 24 hours) phases of IR. TNF ko mice differed from wild-type mice in that TNF ko mice exhibited no activation or induction of nuclear factor-kappa B, p38, cyclin D1, or proliferating cell nuclear antigen after IR. A single low-dose TNF injection 1 minute before the onset of hepatic ischemia restored hepatic IR injury in TNF ko mice. To clarify the importance of TNF for hepatoprotection, preconditioning (10 minutes of ischemia and 10 minutes of reperfusion) was performed before the onset of IR for TNF ko mice whose capacity to undergo IR injury had been restored by TNF replacement. Ischemic preconditioning failed to protect these mice from TNF-augmented IR injury; however, following the administration of intravenous TNF (1 microg per kg body weight, which mimics the early increase in hepatic and plasma TNF levels that is mobilized by ischemic preconditioning), significant hepatoprotection against both the early and late phases of TNF-augmented IR injury was observed. In conclusion, TNF appears to mediate both the early and late phases of liver injury in hepatic IR, but it also is an essential mediator of hepatoprotective effects brought about by ischemic preconditioning.  相似文献   
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The long-acting somatostatin analogue octreotide was used in a patient with severe orthostatic hypotension resistant to conventional treatment. 0.4 ug/kg octreotide given subcutaneously abolished the postural drop in systolic blood pressure for about four hours and was more effective than a combination of fludrocortisone and pindolol.  相似文献   
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OBJECTIVE: Tumor necrosis factor (TNF) is an important proinflammatory cytokine that mediates inflammatory synovitis and articular matrix degradation in rheumatoid arthritis (RA). We investigated the ability of adalimumab, a human anti-TNF monoclonal antibody, to inhibit the progression of structural joint damage, reduce the signs and symptoms, and improve physical function in patients with active RA receiving concomitant treatment with methotrexate (MTX). METHODS: In this multicenter, 52-week, double-blind, placebo-controlled study, 619 patients with active RA who had an inadequate response to MTX were randomized to receive adalimumab 40 mg subcutaneously every other week (n = 207), adalimumab 20 mg subcutaneously every week (n = 212), or placebo (n = 200) plus concomitant MTX. The primary efficacy end points were radiographic progression at week 52 (total Sharp score by a modified method [TSS]), clinical response at week 24 (improvements of at least 20% in the American College of Rheumatology core criteria [ACR20]), and physical function at week 52 (disability index of the Health Assessment Questionnaire [HAQ]). RESULTS: At week 52, there was statistically significantly less radiographic progression, as measured by the change in TSS, in the patients receiving adalimumab either 40 mg every other week (mean +/- SD change 0.1 +/- 4.8) or 20 mg weekly (0.8 +/- 4.9) as compared with that in the placebo group (2.7 +/- 6.8) (P < or = 0.001 for each comparison). In addition, there were statistically significant changes in the components of the TSS. At week 24, ACR20 responses were achieved by 63% and 61% of patients in the adalimumab 40 mg every other week and 20 mg weekly groups, respectively, versus 30% of patients in the placebo group (P < or = 0.001 for each comparison). At week 52, ACR20 responses were achieved by 59% and 55% of patients taking adalimumab 40 mg every other week and 20 mg weekly, respectively, versus 24% of patients taking placebo (P < or = 0.001 for each comparison). At week 52, physical function as measured by the HAQ demonstrated statistically significant improvement with adalimumab 40 mg every other week and 20 mg weekly compared with placebo (mean change in HAQ score -0.59 and -0.61, respectively, versus -0.25; P < or = 0.001 for each comparison). A total of 467 patients (75.4%) completed 52 weeks of treatment. Adalimumab was generally well tolerated. Discontinuations occurred in 22.0% of adalimumab-treated patients and in 30.0% of placebo-treated patients. The rate of adverse events (both serious and nonserious) was comparable in the adalimumab and placebo groups, although the proportion of patients reporting serious infections was higher in patients receiving adalimumab (3.8%) than in those receiving placebo (0.5%) (P < or = 0.02), and was highest in the patients receiving 40 mg every other week. CONCLUSION: In this 52-week trial, adalimumab was more effective than placebo at inhibiting the progression of structural joint damage, reducing the signs and symptoms, and improving physical function in patients with active RA who had demonstrated an incomplete response to MTX.  相似文献   
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BackgroundTHEMIS (The Effect of Ticagrelor on Health Outcomes in Diabetes Mellitus Patients Intervention Study) (n = 19,220) and its pre-specified THEMIS-PCI (The Effect of Ticagrelor on Health Outcomes in Diabetes Mellitus Patients Intervention Study-Percutaneous Coronary Intervention) (n = 11,154) subanalysis showed, in individuals with type 2 diabetes mellitus (median duration 10.0 years; HbA1c 7.1%) and stable coronary artery disease without prior myocardial infarction (MI) or stroke, that ticagrelor plus aspirin (compared with placebo plus aspirin) produced a favorable net clinical benefit (composite of all-cause mortality, MI, stroke, fatal bleeding, and intracranial bleeding) if the patients had a previous percutaneous coronary intervention.ObjectivesIn these post hoc analyses, the authors examined whether the primary efficacy outcome (cardiovascular death, MI, stroke: 3-point major adverse cardiovascular events [MACE]), primary safety outcome (Thrombolysis In Myocardial Infarction–defined major bleeding) and net clinical benefit varied with diabetes-related factors.MethodsOutcomes were analyzed across baseline diabetes duration, HbA1c, and antihyperglycemic medications.ResultsIn THEMIS, the incidence of 3-point MACE increased with diabetes duration (6.7% for ≤5 years, 11.1% for >20 years) and HbA1c (6.4% for ≤6.0%, 11.8% for >10.0%). The relative benefits of ticagrelor plus aspirin on 3-point MACE reduction (hazard ratio [HR]: 0.90; p = 0.04) were generally consistent across subgroups. Major bleeding event rate (overall: 1.6%) did not vary by diabetes duration or HbA1c and was increased similarly by ticagrelor across all subgroups (HR: 2.32; p < 0.001). These findings were mirrored in THEMIS-PCI. The efficacy and safety of ticagrelor plus aspirin did not differ by baseline antihyperglycemic therapy. In THEMIS-PCI, but not THEMIS, ticagrelor generally produced favorable net clinical benefit across diabetes duration, HbA1c, and antihyperglycemic medications.ConclusionTicagrelor plus aspirin yielded generally consistent and favorable net clinical benefit across the diabetes-related factors in THEMIS-PCI but not in the overall THEMIS population.  相似文献   
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It has been reported that the activation of multiple myeloma (MM) cells by CD40 induces proliferation, growth arrest, and apoptosis. To determine whether the biologic sequelae of CD40 activation in MM cells depends on p53 function, we identified temperature-sensitive p53 mutations in the RPMI 8226 (tsp53E285K) and the HS Sultan (tsp53Y163H) MM cell lines. These cells were then used as a model system of inducible wtp53-like function because wild-type-like p53 is induced at permissive (30 degrees C) but not at restrictive (37 degrees C) temperatures. Using p21-luciferase reporter assays, we confirmed that CD40 induces p53 transactivation in RPMI 8226 and HS Sultan cells cultured under permissive, but not restrictive, conditions. Furthermore, CD40 activation of these MM cells under permissive, but not restrictive, temperatures increased the expression of p53 and p21 mRNA and protein. Importantly, CD40 activation induced the proliferation of RPMI 8226 and HS Sultan cells at restrictive temperatures and growth arrest and increased subG1 phase cells at permissive temperatures. These data confirmed that CD40 activation might have distinct biologic sequelae in MM cells, depending on their p53 status.  相似文献   
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Poor angiogenesis within tissue‐engineered grafts has been identified as a main challenge limiting the clinical introduction of bone tissue‐engineering (BTE) approaches for the repair of large bone defects. Thick BTE grafts often exhibit poor cellular viability particularly at the core, leading to graft failure and lack of integration with host tissues. Various BTE approaches have been explored for improving vascularisation in tissue‐engineered constructs and are briefly discussed in this review. Recent investigations relating to co‐culture systems of endothelial and osteoblast‐like cells have shown evidence of BTE efficacy in increasing vascularization in thick constructs. This review provides an overview of key concepts related to bone formation and then focuses on the current state of engineered vascularized co‐culture systems using bone repair as a model. It will also address key questions regarding the generation of clinically relevant vascularized bone constructs as well as potential directions and considerations for research with the objective of pursuing engineered co‐culture systems in other disciplines of vascularized regenerative medicine. The final objective is to generate serious and functional long‐lasting vessels for sustainable angiogenesis that will enable enhanced cellular survival within thick voluminous bone grafts, thereby aiding in bone formation and remodelling in the long term. However, more evidence about the quality of blood vessels formed and its associated functional improvement in bone formation as well as a mechanistic understanding of their interactions are necessary for designing better therapeutic strategies for translation to clinical settings. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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