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BACKGROUND: Microparticles (MP) from endothelial cells (endothelial microparticles; EMP) circulate in disease states, but the processes such as apoptosis or cell activation underlying their release are unclear. OBJECTIVES: We investigated whether adherent (viable) or detached (apoptotic) endothelial cells are the possible source of EMP in vitro, i.e. under control and interleukin (IL)-1alpha activation conditions, and in vivo. METHODS: Adherent and detached endothelial cells, and EMP, were isolated from human umbilical vein endothelial cell cultures (n = 6), treated without or with IL-1alpha (5 ng mL(-1); 24 h). Cell fractions were analyzed by flow cytometry for annexin V binding, propidium iodide (PI) and caspase 3 staining (n = 3). Caspase 3 in EMP was studied using Western blot (n = 6) and flow cytometry (n = 6). Plasma from healthy subjects and systemic lupus erythematosus patients (both n = 3) were analyzed for caspase 3-containing (E)MP. RESULTS: Detached but not adherent cells double-stained for annexin V and PI, confirming the apoptotic conditions of the detached cells and the viable nature of the adherent cells. Caspase 3 was solely present in the detached cells and procaspase 3 in the adherent cells. Caspase 3 was present in EMP from both control and IL-1alpha-treated cultures. Counts of EMP and detached cells, but not adherent cells, highly correlated (r = 0.959, P < 0.0001). In vivo circulating MP from nucleated (endothelial cells, monocytes) and anucleated cells (platelets, erythrocytes) contained caspase 3. CONCLUSIONS: EMP contain caspase 3 and may be mainly derived from detached (apoptotic) endothelial cells in vitro. The presence of caspase 3 in MP from anucleated cell types, however, suggests that its presence may not necessarily be related to apoptosis in vivo but may be associated with caspase 3 activation unrelated to apoptosis.  相似文献   
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Viral diseases like influenza, AIDS, hepatitis, and Ebola cause severe epidemics worldwide. Along with their resistant strains, new pathogenic viruses continue to be discovered so creating an ongoing need for new antiviral treatments. RNA interference is a cellular gene‐silencing phenomenon in which sequence‐specific degradation of target mRNA is achieved by means of complementary short interfering RNA (siRNA) molecules. Short interfering RNA technology affords a potential tractable strategy to combat viral pathogenesis because siRNAs are specific, easy to design, and can be directed against multiple strains of a virus by targeting their conserved gene regions. In this review, we briefly summarize the current status of siRNA therapy for representative examples from different virus families. In addition, other aspects like their design, delivery, medical significance, bioinformatics resources, and limitations are also discussed.  相似文献   
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Whilst quality measures are integral to the maintenance of a high standard of patient care, high-quality care remains a complicated concept to define in the context of acute care. In this article we explore how quality can be measured in the intensive care unit. Standard outcome metrics such as mortality are tangible comparators, but do not offer a comprehensive assessment of quality for the complex heterogeneity of the Intensive care population. We explore the Donabedian model as a means to describe the importance of outcomes, processes, structure and environment to inform the measurement of quality. These concepts can be more abstract and difficult to measure but can provide significant insight into the culture of a unit and the resulting performance, and thus provide a more comprehensive measure of quality.  相似文献   
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Abid S  Mumtaz K  Jafri W  Hamid S  Abbas Z  Shah HA  Khan AH 《Endoscopy》2005,37(8):740-744
BACKGROUND AND STUDY AIMS: Pill-induced esophageal injury is a common but under-reported problem. The purpose of this study was to explore the clinical and endoscopic features, and the outcome of pill-related esophageal injury. PATIENTS AND METHODS: Endoscopy records for the period from January 1997 to June 2003 were searched for reports of esophageal pathology. The records of patients with pill-induced esophageal injury were evaluated. RESULTS: A total of 92 patients with pill-induced esophageal injury were identified (33 men, 59 women; mean age 59, range 25-87). Common symptoms were odynophagia (n = 69, 75 %), chest pain (n = 55, 60 %), vomiting (n = 53, 58 %), dysphagia (n = 31, 33 %), and hematemesis (n = 14, 15 %). The endoscopic findings in the esophagus were: erythema in 76 patients (83 %), erosions in 53 patients (58 %), ulcers in 24 patients (26 %), seven of which were "kissing" ulcers, esophageal ulcer with bleeding in 17 patients (18 %), and esophageal strictures in seven patients (8 %). The causative pills were nonsteroidal anti-inflammatory drugs in 38 patients (41 %), tetracyclines in 20 patients (22 %), potassium chloride tablets in nine patients (10 %), alendronate in eight patients (9 %), and other drugs in 17 patients (18 %). Underlying diseases included diabetes in 60 patients (65 %), ischemic heart disease in 39 patients (42 %), and hypothyroidism in four patients (4 %). The mean hospital stay was 1.94 days; 14 patients (15 %) required injection of epinephrine 1 : 10,000 to control bleeding; and two patients died. CONCLUSIONS: Pill-induced injury may present as erosions, kissing ulcers, and multiple small areas of ulceration with bleeding, mainly in the middle third of the esophagus. Advanced age, female gender, diabetes, and ischemic heart disease were common associations. The majority of patients made an uneventful recovery.  相似文献   
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In order to evaluate the role of ethyl acetate fraction (PNRS-EtOAC) obtained from the Prunus cerasus fruit in the modulation of immune responses, detailed studies were carried out using a panel of in vivo assays. Oral administration of PNRS-EtOAC (25-100 mg/kg) stimulated the IgM and IgG titre expressed in the form of hemagglutination antibody (HA) titre. Further, it elicited a dose related increase in the delayed type hypersensitivity reaction (DTH) after 24 and 48 h in BALB/c mice. Besides augmenting the humoral and cell mediated immune response, the concentration of cytokines (IFN-γ, IL-4, and TNF-α) in serum with respect to T cell interactions, i.e. the proliferation of lymphocytes were significantly increased at 50 mg/kg compared with the control. The results in these studies demonstrated the immunostimulatory effect of PNRS-EtOAC in a dose-dependent manner with respect to the macrophage activation possibly expressing the phagocytosis and nitrite production by the enhancement of TNF-α production as a mode of action.  相似文献   
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