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Septic shock is characterized by increased vascular permeability and hypotension despite increased cardiac output. Numerous vasoactive cytokines are upregulated during sepsis, including angiopoietin 2 (ANG2), which increases vascular permeability. Here we report that mice engineered to inducibly overexpress ANG2 in the endothelium developed sepsis-like hemodynamic alterations, including systemic hypotension, increased cardiac output, and dilatory cardiomyopathy. Conversely, mice with cardiomyocyte-restricted ANG2 overexpression failed to develop hemodynamic alterations. Interestingly, the hemodynamic alterations associated with endothelial-specific overexpression of ANG2 and the loss of capillary-associated pericytes were reversed by intravenous injections of adeno-associated viruses (AAVs) transducing cDNA for angiopoietin 1, a TIE2 ligand that antagonizes ANG2, or AAVs encoding PDGFB, a chemoattractant for pericytes. To confirm the role of ANG2 in sepsis, we i.p. injected LPS into C57BL/6J mice, which rapidly developed hypotension, acute pericyte loss, and increased vascular permeability. Importantly, ANG2 antibody treatment attenuated LPS-induced hemodynamic alterations and reduced the mortality rate at 36 hours from 95% to 61%. These data indicate that ANG2-mediated microvascular disintegration contributes to septic shock and that inhibition of the ANG2/TIE2 interaction during sepsis is a potential therapeutic target.  相似文献   
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A homozygous factor XI-deficient girl, who appeared to be positive for cross-reacting material (CRM+) was studied for clarification. Factor XI antigen (F XI:Ag) was measured by radial immunodiffusion using monospecific, heterologous anti-factor XI antibodies. Factor XI coagulant activity (F XI:C) was determined in a modified activated partial thromboplastin time (APTT) test. The ratio of F XI:C to F XI:Ag was 0.04 for the proposita, as compared with 0.7 to 0.74 in the other family members. In contrast, 12 normal individuals had ratios of F XI:C to F XI:Ag of 1.04 +/- 0.15. F XI esterolytic activity was clearly higher than F XI:C in the proband, but not in her relatives. Immunoblotting studies demonstrated F XI CRM in the patient's plasma. Chromatography on diethylaminoethanol (DEAE)-Sephadex at pH 8.4 led to an almost complete removal of F XI from the plasma. The defective F XI was not bound to a negatively charged kaolin surface due to an abnormal interaction with high-mol-wt kininogen (HMWK).  相似文献   
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ABSTRACT

Background

Stroke is the leading cause for admission to the nearly 1,200 Inpatient Rehabilitation Facilities (IRFs) nationally in the US. For many patients, post-acute care is an important component of their rehabilitation. Several quality measures have been publicly reported for post-acute care providers, including hospital readmissions. However, to date none have focused on specific medical conditions, limiting the usability for patients and quality improvement.  相似文献   
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In functional neuroimaging studies, individuals with dyslexia frequently exhibit both hypoactivation, often in the left parietotemporal cortex, and hyperactivation, often in the left inferior frontal cortex, but there has been no evidence to suggest how to interpret the differential relations of hypoactivation and hyperactivation to dyslexia. To address this question, we measured brain activation by functional MRI during visual word rhyme judgment compared with visual cross-hair fixation rest, and we measured gray matter morphology by voxel-based morphometry in dyslexic adolescents in comparison with (i) an age-matched group, and (ii) a reading-matched group younger than the dyslexic group but equal to the dyslexic group in reading performance. Relative to the age-matched group (n = 19; mean 14.4 years), the dyslexic group (n = 19; mean 14.4 years) exhibited hypoactivation in left parietal and bilateral fusiform cortices and hyperactivation in left inferior and middle frontal gyri, caudate, and thalamus. Relative to the reading-matched group (n = 12; mean 9.8 years), the dyslexic group (n = 12; mean 14.5 years) also exhibited hypoactivation in left parietal and fusiform regions but equal activation in all four areas that had exhibited hyperactivation relative to age-matched controls as well. In regions that exhibited atypical activation in the dyslexic group, only the left parietal region exhibited reduced gray matter volume relative to both control groups. Thus, areas of hyperactivation in dyslexia reflected processes related to the level of current reading ability independent of dyslexia. In contrast, areas of hypoactivation in dyslexia reflected functional atypicalities related to dyslexia itself, independent of current reading ability, and related to atypical brain morphology in dyslexia.  相似文献   
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Classical interferon-alpha has been shown to be correlated with the development of a variety of autoimmune disorders. A 38 year-old female patient developed simultaneously diabetic ketoacidosis and hyperthyroidism 5 mo following initiation of treatment with pegylated interferon-α and ribavirin for chronic hepatitis C. High titers of glutamic acid decarboxylase, antinuclear and thyroid (thyroid peroxidase and thyroglobulin) antibodies were detected. Antiviral treatment was withdrawn and the patient was treated with insulin for insulin-dependent diabetes mellitus and propranolol for hyperthyroidism. Twelve months after cessation of pegylated interferon-α therapy the patient was euthyroid without any medication but remained insulin-dependent.  相似文献   
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OBJECTIVES: Cysteamine prevents organ damage in children with cystinosis, but may cause gastrointestinal (GI) symptoms. In this study we evaluated the nature of GI disease, and the value of omeprazole in controlling GI symptoms in these children. STUDY DESIGN: Upper GI disease was evaluated with endoscopy, gastrin levels, and acid secretion studies after oral administration of cysteamine, before and after 16 weeks of therapy with omeprazole. A symptom score was devised. RESULTS: Eleven children (mean age, 5.7 years) were studied. After cysteamine ingestion, before and after omeprazole therapy, the mean maximum acid output was significantly higher than the mean basal acid output. The maximum acid output was measured within 60 minutes of cysteamine ingestion and was reduced by omeprazole therapy (P<.01). The mean peak gastrin level was 30 minutes postcysteamine and was higher than baseline (P<.01). The initial mean symptom score (maximum score, 14) was 6.9 and fell to 0.7 (P<.0001) after 16 weeks of omeprazole therapy. At endoscopy, two children had diffuse gastric nodularity, and nearly all had cystine crystal deposits. CONCLUSIONS: GI symptoms in children with cystinosis receiving cysteamine are often acid-mediated and improve with omeprazole. Cystine crystals were detected in the GI tract and may signify inadequate treatment with cysteamine.  相似文献   
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