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41.
BACKGROUNDMost of the randomized clinical trials that led to the wide use of non-vitamin K antagonist oral anticoagulants for stroke prevention in patients with atrial fibrillation (AF) originated from western countries. AIMTo systematically review and quantitatively synthesize the real-world data regarding the efficacy and safety of dabigatran, rivaroxaban, and apixaban compared to warfarin for stroke prevention in Asian patients with non-valvular AF.METHODSMedline, Cochrane, and ClinicalTrial.gov databases were reviewed. A random-effect model meta-analysis was used and I-square was utilized to assess the heterogeneity. The primary outcome was ischemic stroke. The secondary outcomes were all-cause mortality, major bleeding, intracranial hemorrhage, and gastrointestinal bleeding.RESULTSTwelve studies from East Asia or Southeast Asia and 441450 patients were included. Dabigatran, rivaroxaban, and apixaban were associated with a significant reduction in the incidence of ischemic stroke [hazard ratio (HR) = 0.78, 95% confidence interval (CI): 0.65-0.94; HR = 0.79, 95%CI: 0.74-0.85, HR = 0.70, 95%CI: 0.62-0.78; respectively], all-cause mortality (HR = 0.68, 95%CI: 0.56-0.83; HR = 0.66, 95%CI: 0.52-0.84; HR = 0.66, 95%CI: 0.49-0.90; respectively), and major bleeding (HR = 0.61, 95%CI: 0.54-0.69; HR = 0.70, 95%CI: 0.54-0.90; HR = 0.58, 95%CI: 0.43-0.78; respectively) compared to warfarin.CONCLUSIONDabigatran, rivaroxaban, and apixaban appear to be superior to warfarin in both efficacy and safety in Asians with non-valvular AF.  相似文献   
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Hepatic encephalopathy can be a life-threatening complication of fulminant hepatic failure. By understanding the pathophysiology involved in the induction of this neuropsychiatric disorder, future therapeutic and/or preventive attempts could be considered. In this study, an attempt has been made in order to shed more light on the mechanisms involved in the effects of thioacetamide (TAA)-induced fulminant hepatic encephalopathy on: (a) the adult rat brain total antioxidant status (TAS) and (b) the activities of acetylcholinesterase (AChE), (Na(+),K(+))-ATPase and Mg(2+)-ATPase. Moreover, in vitro experiments were conducted in order to evaluate the possible role of ammonia (incubated as NH(4)Cl, in a toxic concentration of 3mM) in the observed effects of TAA-induced fulminant hepatic encephalopathy on the examined adult rat brain enzyme activities. Fulminant hepatic encephalopathy caused a significant decrease in TAS (-22%, p < 0.001) and the activity of Na(+),K(+)-ATPase (-26%, p < 0.001), but had non-significant effects on the whole brain AChE and Mg(2+)-ATPase activities. The in vitro experiments (conducted through a 3h incubation with ammonia), showed no significant alterations in any of the examined parameters. Our in vitro and in vivo findings suggest that alterations in AChE and Mg(2+)-ATPase activities are not involved in the pathophysiology of the adult-onset fulminant hepatic encephalopathy, while the observed Na(+),K(+)-ATPase inhibition could be a result of the oxidative stress, neurotransmission deregulation, and/or of the presence of other toxic substances (that appear to act as direct or indirect inhibitors of the enzyme) and not due to the excess accumulation of ammonia in the brain.  相似文献   
43.

Background

The Amplatzer™ Amulet™ (Amulet) is the evolution of the Amplatzer™ Cardiac Plug, a dedicated device for percutaneous left atrial appendage (LAA) occlusion. The new device has been designed to facilitate the implantation process, improve the sealing performance and further reduce the risk of complications. The objective of the study was to describe the initial experience with the Amplatzer Amulet for percutaneous LAA occlusion.

Methods

This was a prospective single-center study of patients undergoing percutaneous LAA occlusion. The indication for LAA closure was a formal contraindication for oral anticoagulation or previous history of stroke due to INR lability. All procedures were done under general anesthesia and transesophageal echocardiography (TEE) guidance. Transthoracic echocardiography was performed 24 h after the procedure in order to rule out procedural complications before discharge. Further follow-up was done with a clinical visit and TEE at 1–3 months.

Results

Between July-2012 and June-2013, 25 patients with a mean CHA2DS2-VASC of 4.3 ± 1.7 underwent LAA occlusion with the Amplatzer Amulet. The device was successfully implanted in 24 patients (96%) without any procedural stroke, pericardial effusion or device embolization. None of the patients presented any clinical event at follow-up. Follow-up TEE showed complete LAA sealing in all patients with no residual leaks > 3 mm and no device embolization. One patient (4.1%) presented a device thrombosis at follow-up without clinical expression.

Conclusion

In this initial series of patients, the Amulet showed a remarkable acute and short-term performance in terms of feasibility and safety as depicted by the high successful implantation rate and the low incidence of complications.  相似文献   
44.
Abstract

Background: Except for pancreas divisum (PD), the prevalence of anatomic variants of the main pancreatic duct (MPD) seems to be insufficiently investigated. To date, their role in the occurrence of pancreatic exocrine insufficiency (PEI) and morphological changes suggestive of chronic pancreatitis (CP) has remained unclear.

Methods: A systematic review was performed, searching MEDLINE and Web of Science, limited to articles published between 1960 and 1 June 2019.

Results: Our review included a total number of 3234 subjects. The most common variant of MPD was type 3, followed by type 1, indicating MPD drainage pattern into major papilla (MP) as the most frequent. A sub-variant of type 3, known as ‘reverse pancreas divisum’ had a prevalence of 2.2%. Type 4 variant- PD, was found in 6.4% of all cases. The most common sub-variant of PD was complete PD, followed by incomplete PD and variant with MPD as only pancreatic duct. Type 5 variant (including ansa pancreatica) was present in 2.9% of subjects. Apart from one study with a significantly higher frequency of morphological changes suggestive of CP in patients with ansa pancreatica, the studies stated no significant association between pancreatic disease and MPD variants. Furthermore, only one study examined the influence of MPD variants on exocrine pancreatic function. Although equivocal, this association is most likely found to be insignificant.

Conclusion: To elucidate linkage between MPD variants and the occurrence of chronic pancreatitis and impairment of pancreatic exocrine function, further clinical investigations are warranted.  相似文献   
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Objectives:To emerge hypoperfusion of lower limbs in patients with critical limb ischemia (CLI) using Intravoxel Incoherent Motion microperfusion magnetic resonance imaging (IVIM-MRI). Moreover to examine the ability of IVIM-MRI to differentiate patients with severe peripheral arterial disease (PAD) from normal subjects and evaluate the percutaneous transluminal angioplasty (PTA) results in patients with CLI.Methods:Eight patients who presented with CLI and six healthy volunteers were examined. The patients underwent IVIM-MRI of lower extremity before and following PTA. The imaging protocol included sagittal diffusion-weighted (DW) sequences. DW images were analyzed and color parametric maps of the micro-circulation of blood inside the capillary network (D*) were constructed. The studies were evaluated by two observers to define interobserver reproducibility.Results:Technical success was achieved in all patients (8/8). The mean ankle-brachial index increased from 0.35 ± 0.2 to 0.76 ± 0.25 (p < 0.05). Successful revascularization improved IVIM microperfusion. Mean D* increased from 279.88 ± 13.47 10−5 mm2/s to 331.51 ± 31 10−5 mm2/s, following PTA, p < 0.05. Moreover, PAD patients presented lower D* values as compared to healthy individuals (279.88 ± 13.47 10−5 mm2/s vs 332.47 ± 22.95 10−5 mm2/s, p < 0.05, respectively). Good interobserver agreement was obtained with an ICC = 0.84 (95% CI 0.64–0.93).Conclusions:IVIM-MRI can detect differences in microperfusion between patients with PAD and healthy individuals. Moreover, significant restitution of IVIM microperfusion is found following successful PTA.Advances in knowledge:IVIM-MRI is a safe, reproducible and effective modality for evaluation of lower limb hypoperfusion in patients with PAD. It seems also to be a helpful tool to detect changes of tissue perfusion in patients with CLI following revascularization.  相似文献   
48.
Objective. To investigate the effect of interferon-γ (IFNγ) on the adhesive interactions between human peripheral blood T cells and human skeletal muscle cells at various stages of muscle cell differentiation and maturation in vitro. Methods. Human muscle cell cultures were established from normal muscle biopsy material, using the explant technique. T cells were studied for their capacity to adhere to IFNγ-treated and untreated myoblasts and myotubes. The role of intercellular adhesion molecule type 1 (ICAM-1) in cell adhesion to muscle cells was examined in blocking studies, by enzyme-linked immuno-sorbent assay (ELISA), and by immunohistochemical staining using monoclonal antibodies (MAb). Results. Treatment of muscle cells (myoblasts and myotubes) with IFNγ resulted in a significant dose-dependent increase in the number of adherent T cells. Adhesion of T cells to muscle cells was significantly inhibited by MAb to ICAM-1 and to lymphocyte function–associated antigen type 1, but not by MAb to HLA–DR. There was no difference in the level of T cell adhesion to IFNγ-treated allogeneic versus autologous muscle cells. By ELISA and immunohistochemical analysis, ICAM-1 expression on the surface of cultured human muscle cells was either absent or barely detectable, but was strongly induced by treatment of muscle cells with IFNγ. Conclusion. Induction of cell adhesion molecules on muscle cells by IFNγ may be an important mechanism for the localization of T cells in the affected muscles of patients with autoimmune myositis.  相似文献   
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