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991.
Greenwood JP Maredia N Younger JF Brown JM Nixon J Everett CC Bijsterveld P Ridgway JP Radjenovic A Dickinson CJ Ball SG Plein S 《Lancet》2012,379(9814):453-460
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Sheedy D Say M Stevens J Harper CG Kril JJ 《Alcoholism, clinical and experimental research》2012,36(1):55-60
Background: Postmortem brain tissue provides an important resource to investigate various brain disorders, including those resulting from the effects of alcohol abuse. Unlike the traditionally recognized confounders to tissue quality (e.g., coma, hypoxia), our understanding of the effects of liver disease is incomplete. The aim of this study was to determine the effects of liver pathology, and in particular cirrhosis resulting in hepatic encephalopathy (HE), on 2 postmortem brain tissue quality markers, brain pH and RNA integrity. Methods: We measured tissue quality markers in a cohort of alcohol abuse and control cases collected by the NSW Tissue Resource Centre. Cerebellar tissue was used to evaluate both brain pH and RNA quality (as indicated by the RNA integrity number: RIN). A histological assessment was performed on each case to exclude coexisting pathologies (e.g., cerebrovascular disease, hypoxic encephalopathy, neurodegenerative disease) and to assess the presence or absence of HE. Autopsy reports were reviewed for liver pathology and toxicology. Results: Analysis revealed that cases of alcohol abuse had a lower mean (±SD) brain pH, 6.46 (±0.3) as compared with the control mean 6.64 (±0.2). The mean RIN for the alcohol abuse group was 6.97 (±1.3) and controls 7.66 (±0.5). The severity of liver pathology affected both brain pH (p < 0.0001) and RIN (p < 0.0001). The comparison between cirrhotic cases highlighted increased degradation of RNA in cases with cirrhosis resulting in HE (p = 0.0095). A similar effect was seen on brain pH (p = 0.0019). Conclusions: The results show that the presence of cirrhosis and, more so, HE reduces the pH and RIN of postmortem brain tissue. 相似文献
995.
Heart failure (HF) has steadily increased in prevalence and affects both males and females equally. Despite this, there has been a significant underrepresentation of women in large scale HF trials. This disparity has lead to a deficit in understanding important gender-based differences in pathophysiology, diagnosis and treatment strategies. We review these gaps and explore a biological basis for varying outcomes. Endogenous estrogen plays an important role in epidemiology and outcome. The administration of exogenous estrogen has had varied success in treatment and is outlined extensively below. Additionally, we highlight unique HF syndromes through pregnancy and important sex-specific issues concerning transplant and mechanical circulatory support. A central theme remains: there is a clear need for increased female recruitment in clinical trials, and more studies exploring the role of gender-based biology in HF treatment. 相似文献
996.
Meune C Twerenbold R Drexler B Balmelli C Wolf C Haaf P Reichlin T Irfan A Reiter M Zellweger C Meissner J Stelzig C Freese M Capodarve I Mueller C 《The American journal of cardiology》2012,109(8):1117-1123
We hypothesized that midregional pro-A-type natriuretic peptide (MR-proANP), the stable midregional epitope of proANP, might be useful in the early diagnosis and risk stratification of patients with suspected acute myocardial infarction (AMI). In this multicenter study we measured MR-proANP, cardiac troponin T (cTnT), and high-sensitive cTnT (hs-cTnT) at presentation in 675 consecutive patients presenting to the emergency department with suspected AMI. The final diagnosis was adjudicated by 2 independent cardiologists. Patients were followed 360 days for mortality and AMI. AMI was the final diagnosis in 119 patients (18%). Median MR-proANP levels at presentation were significantly higher in patients with AMI (189 pmol/L, interquartile range 97 to 341) versus patients with another final diagnosis (83 pmol/L, 49 to 144, p <0.001). However, neither the combination of MR-proANP with cTnT nor its combination with hs-cTnT significantly improved diagnostic accuracy as quantified by area under the receiver operating characteristic curve (0.91 vs 0.89 for cTnT alone, p = 0.086; 0.95 vs 0.96 for hs-cTnT, respectively, p = 0.02). Cumulative 360-day mortality/AMI rates were 2.4% in the first, 3.6% in the second, 9.5% in the third, and 18.8% in the fourth quartiles of MR-proANP (p <0.001). MR-proANP (area under the curve 0.76) predicted mortality/AMI independently of and more accurately than cTnT (area under the curve 0.62), hs-cTnT (area under the curve 0.71), and Thrombolysis In Myocardial Infarction risk score (area under the curve 0.72). Net reclassification improvements offered by the additional use of MR-proANP were 0.388 (p <0.001), 0.425 (p <0.001), and 0.217 (p = 0.007), respectively. In conclusion, MR-proANP improves risk prediction for 360-day mortality/AMI but does not seem to help in the early diagnosis of AMI. 相似文献
997.
Mahan CS Zalwango S Thiel BA Malone LL Chervenak KA Baseke J Dobbs D Stein CM Mayanja H Joloba M Whalen CC Boom WH 《The American journal of tropical medicine and hygiene》2012,86(4):690-697
Contacts of active pulmonary tuberculosis (TB) patients are at risk for Mycobacterium tuberculosis (MTB) infection. Because most infections are controlled, studies during MTB infection provide insight into protective immunity. We compared immune responses of adult household contacts that did and did not convert the tuberculin skin test (TST). Innate and adaptive immune responses were measured by whole blood assay. Responses of TST converters (TSTC) were compared with persistently TST negative contacts (PTST-) and contacts who were TST+ at baseline (TST+). TLR-2, TLR-4, and IFN-γR responses to IFN-γ did not differ between the groups, nor did γδ T cell responses. T cell responses to MTB antigens differed markedly among TSTC, PTST-, and TST+ contacts. Thus, no differences in innate responses were found among the three household contact groups. However, adaptive T cell responses to MTB antigens did differ before and during MTB infection among PTST-, TSTC, and TST+ contacts. 相似文献
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Throndson RR Baker D Kennedy P McDaniel K 《Oral surgery, oral medicine, oral pathology and oral radiology》2012,113(2):229-233
Hemophilic pseudotumor is a rare lesion that is essentially a progressive, slowly expanding, encapsulated hematoma. It is estimated to affect 1% to 2% of severe hemophiliacs. The majority of hemophilic pseudotumors occur within soft tissues (intramuscular) and long bones of adult males. Fewer than 20 cases have been reported in the maxillofacial region. We report a rare case occurring in the mandible of a 14-year-old boy who presented with considerable expansion and displacement of teeth. 相似文献