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Objective. To study the distribution of intercellular adhesion molecule receptor (ICAM-R, or ICAM-3), a novel ligand for the leukointegrin lymphocyte function-associated antigen 1 (LFA-1), in normal and rheumatoid synovial membranes and to compare this with the distribution of ICAM-1, ICAM-2, vascular cell adhesion molecule 1 (VCAM-1), and endothelial leukocyte adhesion molecule 1 (ELAM-1). Methods. We performed immunohistochemical analyses of frozen sections of normal and rheumatoid synovial tissue using monoclonal antibodies to the molecules examined. Results. ICAM-1 staining was detectable on the vascular endothelium and the synovial lining cells of both normal and rheumatoid synovial membranes. A variable proportion of lymphocytes infiltrating rheumatoid tissues expressed ICAM-1. ICAM-2 staining was demonstrable in the vascular endothelium of both normal and inflamed tissues, the latter demonstrating a significantly higher proportion of positive vessels. ELAM-1 staining was not detectable in normal synovial membranes but was seen on the endothelium of a limited number of rheumatoid synovial vessels, usually close to the synovial lining cell layer. VCAM-1 staining was intense in both normal and rheumatoid synovial lining cells, but vascular staining was weak in both. In contrast, ICAM-R staining was not detected in association with any synovial blood vessels, but was widely expressed by lymphocytes and macrophages. Cells of the lining layer did not stain for ICAM-R. Conclusion. Although ICAM-R is a ligand for LFA-1 and shares considerable sequence homology with ICAM-1 and ICAM-2, it does not appear to be expressed by the endothelium of normal or inflamed synovial vessels. Intense expression of ICAM-R by rheumatoid synovial lymphocytes and macrophages suggests that it may play a role in processes requiring cell-cell contact, such as antigen presentation and homotypic aggregation.  相似文献   
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Extracorporeal membrane oxygenation (ECMO) is considered as a supportive treatment that provides circulatory and ventilatory support and can be thought off as a bridge to organ recovery. Since 2009, it has been applied as a rescue treatment for patients with severe adult respiratory distress syndrome (ARDS) mainly due to viral causes. In December 2019, several patients presented with a constellation of symptoms of viral pneumonia in China. A new strain of the corona virus family, called COVID-19, has been discovered to be the cause of this severe mysterious illness that was named severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2). This new virus continued to spread across the globe leading to the World Health Organization announcing it as a pandemic in the early 2020. By the end of March 2021, the number of COVID-19 cases worldwide exceeded 126 million cases. In Saudi Arabia, the first confirmed case of COVID-19 was reported in the 2nd March 2020. By the end of March 2021, the total number of confirmed COVID-19 cases in Saudi Arabia is just above 360,000. In anticipation of the need of ECMO for the treatment of patients with SARS‑CoV‑2 based on the previous Middle East respiratory syndrome coronavirus pandemic experience, the Saudi Extra-Corporeal Life Support (ECLS) chapter that is under the umbrella of the Saudi Critical Care Society (SCCS) convened a working group of ECMO experts. The mission of this group was to formulate a guidance for the use of ECMO as a last resort for patients with severe ARDS, especially with COVID-19 based on available evidence. The ECLS-SCCS chapter wanted to generate a document that can be used to simple guide, with a focus on safety, to provide ECMO service for patients with severe ARDS with a special focus on SARS‑CoV‑2.  相似文献   
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Cancer Chemotherapy and Pharmacology - CC-486 is an oral formulation of azacitidine that allows for extended dosing schedules to prolong azacitidine exposure to malignant cells and maximize...  相似文献   
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BackgroundGastric cancer (GC) is a leading cause of cancer-related death in the world and most patients have advanced disease upon presentation. The effect of age on prognosis in GC is controversial. We aimed to determine the impact of age on survival in patients with GC.MethodsThis was a retrospective study of the medical records of Lebanese patients diagnosed with GC at the American University of Beirut Medical Center (AUBMC) between 2005 and 2014. Patients were divided into young (<65 years) and older groups (≥65 years). A multivariate analysis was done to determine the independent predictors of survival. Kaplan-Meier method was used for analysis of long-term survival outcomes.ResultsThe sample consisted of 156 patients. The mean age was 62.15 (SD 13.54). Most patients presented with stage 4 disease (62.2%) and poorly differentiated histology (66.4%). The most common symptoms were abdominal pain and weight loss. On bivariate analysis, advanced stage (P=0.02) and higher grade (P=0.04) were associated with increased mortality. Patients <65 years of age were significantly more likely to have poorly differentiated tumours, while patients ≥65 years had more comorbidities (P=0.001). The 5-year DFS were 35% and 37% for patients <65 years of age and ≥65 years of age, respectively (P=0.15).ConclusionsHigher grade and advanced stage are associated with worse survival in patients with GC, but age did not seem to have an impact. Screening high risk patients and early diagnosis are necessary to improve survival.  相似文献   
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ObjectivesThe aim of this study was to examine the temporal trends and outcomes of mechanical complications after myocardial infarction in the contemporary era.BackgroundData regarding temporal trends and outcomes of mechanical complications after ST-segment elevation myocardial infarction (STEMI) and non–ST-segment elevation myocardial infarction (NSTEMI) are limited in the contemporary era.MethodsThe National Inpatient Sample database (2003 to September 2015) was queried to identify all STEMI and NSTEMI hospitalizations. Temporal trends and outcomes of mechanical complications after STEMI and NSTEMI, including papillary muscle rupture, ventricular septal defect, and free wall rupture, were described.ResultsThe analysis included 3,951,861 STEMI and 5,114,270 NSTEMI hospitalizations. Mechanical complications occurred in 10,726 of STEMI hospitalizations (0.27%) and 3,041 of NSTEMI hospitalizations (0.06%), with no changes in trends (p = 0.13 and p = 0.83, respectively). The rates of in-hospital mortality in patients with mechanical complications were 42.4% after STEMI and 18.0% after NSTEMI, with no significant trend changes (p = 0.62 and p = 0.12, respectively). After multivariate adjustment, patients who had mechanical complications after myocardial infarction had higher in-hospital mortality, cardiogenic shock, acute kidney injury, hemodialysis, and respiratory complications compared with those without mechanical complications. Predictors of lower mortality in patients with mechanical complications who developed cardiogenic shock included surgical repair in the STEMI and NSTEMI cohorts and percutaneous coronary intervention in the STEMI cohort.ConclusionsContemporary data from a large national database show that the rates of mechanical complications are low in patients presenting with STEMI and NSTEMI. Post–myocardial infarction mechanical complications continue to be associated with high mortality rates, which did not improve during the study period.  相似文献   
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