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91.
SUMMARY. To investigate the clinical significance of determination of plasma tissue factor (TF) antigen, we have developed a highly sensitive enzyme-linked immunosorbent assay (ELISA) for plasma TF, using two different monoclonal antibodies against TF apoprotein, 6B4 (catching antibody) and 5G9 (detecting antibody), and tetramethyl benzidine/H2O2 as substrates. Titration curves of recombinant human TF in buffer containing Triton X-100 were linear within the range from 50 to 2000pg/ml. The total assay time was 3h. Ultracentrifugation and immunoblot analysis indicated that human plasma and urine contained 50 000 g sedimentable and non-sedimentable forms of TF, both of which were detected by our ELISA method.
Plasma and urine concentrations of TF in healthy subjects and patients with various diseases were measured by the ELISA method. In healthy subjects, plasma and urinary TF levels were found to be 149± 72pg/ml (n = 30) and 175±60pg TF/urine creatinine mg (n = 95). respectively. TF was increased in plasma of patients with disseminated intravascular coagulation (DIC), thrombotic thrombocytopenic purpura, vasculitis associated with collagen diseases, diabetic microangiopathy and chronic renal failure receiving haemodialysis, but not in the plasma of endotoxaemic patients without DIC. The plasma TF/serum creatinine ratio did not show a positive correlation. Measurement of TF antigen in plasma may be useful for evaluating the endothelial damage and cell destruction in TF-containing tissues.  相似文献   
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Women with pulmonary arterial hypertension (PAH) exhibit better right ventricular (RV) function and survival than men; however, the underlying mechanisms are unknown. We hypothesized that 17β-estradiol (E2), through estrogen receptor α (ER-α), attenuates PAH-induced RV failure (RVF) by upregulating the procontractile and prosurvival peptide apelin via a BMPR2-dependent mechanism. We found that ER-α and apelin expression were decreased in RV homogenates from patients with RVF and from rats with maladaptive (but not adaptive) RV remodeling. RV cardiomyocyte apelin abundance increased in vivo or in vitro after treatment with E2 or ER-α agonist. Studies employing ER-α–null or ER-β–null mice, ER-α loss-of-function mutant rats, or siRNA demonstrated that ER-α is necessary for E2 to upregulate RV apelin. E2 and ER-α increased BMPR2 in pulmonary hypertension RVs and in isolated RV cardiomyocytes, associated with ER-α binding to the Bmpr2 promoter. BMPR2 is required for E2-mediated increases in apelin abundance, and both BMPR2 and apelin are necessary for E2 to exert RV-protective effects. E2 or ER-α agonist rescued monocrotaline pulmonary hypertension and restored RV apelin and BMPR2. We identified what we believe to be a novel cardioprotective E2/ER-α/BMPR2/apelin axis in the RV. Harnessing this axis may lead to novel RV-targeted therapies for PAH patients of either sex.  相似文献   
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Fragile X-associated tremor/ataxia syndrome (FXTAS), a late-onset movement disorder affecting FMR1 premutation carriers, is associated with cerebral and cerebellar lesions. The aim of this study was to test whether computational anatomy can detect similar patterns in asymptomatic FMR1 premutation carriers (mean age 46.7 years) with qualitatively normal -appearing grey and white matter on brain MRI. We used a multimodal imaging protocol to characterize brain anatomy by automated assessment of gray matter volume and white matter properties. Structural changes in the hippocampus and in the cerebellar motor network with decreased gray matter volume in lobule VI and white matter alterations of the corresponding afferent projections through the middle cerebellar peduncles are demonstrated. Diffuse subcortical white matter changes in both hemispheres, without corresponding gray matter alterations, are only identified through age × group interactions. We interpret the hippocampal fimbria and cerebellar changes as early alterations with a possible neurodevelopmental origin. In contrast, progression of the diffuse cerebral hemispheric white matter changes suggests a neurodegenerative process, leading to late-onset lesions, which may mark the imminent onset of FXTAS.  相似文献   
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Methicillin-resistant Staphylococcus aureus (MRSA) strains from different geographic areas have different genetic backgrounds, suggesting independent clonal evolutions. To better understand the virulence of MRSA strains and the relationship to their clonal and geographic origins, we undertook an analysis of epidemiologic, molecular, and virulence characteristics of a large number of MRSA isolates from geographically diverse origins, in a Caenorhabditis elegans infection model. A total of 99 MRSA isolates collected between 1993 and 2010 at the Geneva University Hospitals from diverse global origins were characterized with Panton–Valentine leukocidin (PVL), toxic shock syndrome toxin (TSST), accessory gene regulator (agr) group, staphylococcal cassette chromosome mec (SCCmec), S. aureus protein A (spa), multilocus sequence typing (MLST), and pulsed-field gel electrophoresis (PFGE) typing. Epidemiologic data were provided from clinical records. The bacterial virulence was tested in a C. elegans host model. The inter-relationships of epidemiological/molecular characteristics in association with nematocidal activities were analyzed with univariate and two-factor analysis of variance (ANOVA). Community-associated MRSA (CA-MRSA) strains were more virulent than hospital-associated MRSA (HA-MRSA), with higher nematocidal activities in CA-MRSA strains (0.776 vs. 0.506, p?=?0.0005). All molecular characteristics (PVL, TSST, spa, SCCmec, MLST, and PFGE types) showed a significant association with nematocidal activities on univariate analysis (p?<?0.005). PVL was not a significant predictor after adjusting for genomic backgrounds using spa, MLST, or PFGE typing. The dominant CA-MRSA strains in North America showed higher nematocidal activities than strains from other regions (p?<?0.0001). Strains with global origins containing distinct genetic backgrounds have different virulence in the C. elegans model. Nematocidal activities were most highly correlated with SCCmec, spa, MLST, and PFGE typing, suggesting that genomic background rather than a single exotoxin characteristic was the most discriminating predictor of virulence.  相似文献   
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ObjectiveProfessional medical interpreters facilitate patient understanding of illness, prognosis, and treatment options. Facilitating end of life discussions can be challenging. Our objective was to better understand the challenges professional medical interpreters face and how they affect the accuracy of provider-patient communication during discussions of end of life.MethodsWe conducted semi-structured interviews with professional Spanish medical interpreters. We asked about their experiences interpreting end of life discussions, including questions about values, professional and emotional challenges interpreting these conversations, and how those challenges might impact accuracy. We used a grounded theory, constant comparative method to analyze the data. Participants completed a short demographic questionnaire.ResultsSeventeen Spanish language interpreters participated. Participants described intensive attention to communication accuracy during end of life discussions, even when discussions caused emotional or professional distress. Professional strains such as rapid discussion tempo contributed to unintentional alterations in discussion content. Perceived non-empathic behaviors of providers contributed to rare, intentional alterations in discussion flow and content.ConclusionWe found that despite challenges, Spanish language interpreters focus intensively on accurate interpretation in discussions of end of life.Practice ImplicationsProvider training on how to best work with interpreters in these important conversations could support accurate and empathetic interpretation.  相似文献   
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