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Jason B Cook Stephanie M Nelli Mackenzie R Neighbors Danielle H Morrow Todd K O'Buckley Antoniette M Maldonado-Devincci A Leslie Morrow 《Neuropsychopharmacology》2014,39(8):1978-1987
The neuroactive steroid (3α,5α)-3-hydroxypregnan-20-one (3α,5α-THP or allopregnanolone) is a positive modulator of GABAA receptors synthesized in the brain, adrenal glands, and gonads. In rats, ethanol activates the hypothalamic–pituitary–adrenal axis and elevates 3α,5α-THP in plasma, cerebral cortex, and hippocampus. In vivo, these effects are dependent on both the pituitary and adrenal glands. In vitro, however, ethanol locally increases 3α,5α-THP in hippocampal slices, in the absence of adrenal influence. Therefore, it is not known whether ethanol can change local brain levels of 3α,5α-THP in vivo, independent of the adrenals. To directly address this controversy, we administered ethanol (2 g/kg) or saline to rats that underwent adrenalectomy (ADX) or received sham surgery and performed immunohistochemistry for 3α,5α-THP. In the medial prefrontal cortex (mPFC), ethanol increased 3α,5α-THP after sham surgery, compared with saline controls, with no ethanol-induced change in 3α,5α-THP following ADX. In subcortical regions, 3α,5α-THP was increased independent of adrenals in the CA1 pyramidal cell layer, dentate gyrus polymorphic layer, bed nucleus of the stria terminalis, and paraventricular nucleus of the hypothalamus. Furthermore, ethanol decreased 3α,5α-THP labeling in the nucleus accumbens shore and central nucleus of the amygdala, independent of the adrenal glands. These data indicate that ethanol dynamically regulates local 3α,5α-THP levels in several subcortical regions; however, the adrenal glands contribute to 3α,5α-THP elevations in the mPFC. Using double immunofluorescent labeling we determined that adrenal dependence of 3α,5α-THP induction by ethanol is not due to a lack of colocalization of 3α,5α-THP with the cholesterol transporters steroidogenic acute regulatory protein (StAR) or translocator protein (TSPO). 相似文献
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Whole breast irradiation (WBI) over 5–7 weeks has long been considered standard adjuvant treatment after breast-conserving surgery. Recently the concept of irradiating the whole breast has been challenged by accelerated partial breast irradiation (APBI), which exclusively targets the lumpectomy site plus margin. We review the evidence supporting APBI from modern clinical trials, the pros and cons of various APBI techniques, and the controversies regarding the applicability of APBI to specific patient groups. 相似文献
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Gibson CM Karha J Murphy SA James D Morrow DA Cannon CP Giugliano RP Antman EM Braunwald E;TIMI Study Group 《Journal of the American College of Cardiology》2003,42(1):7-16
OBJECTIVES: We hypothesized that early recurrent myocardial infarction (MI) following fibrinolytic administration would be assessed with higher mortality at both 30 days and 2 years. BACKGROUND: Although early recurrent MI after fibrinolytic therapy has been associated with increased early mortality in the acute MI setting, its relation to long-term mortality has not been fully explored. METHODS: Mortality data were ascertained in 20,101 patients enrolled in the Thrombolysis In Myocardial Infarction (TIMI) 4, 9, and 10B and Intravenous NPA for the Treatment of Infarcting Myocardium Early (InTIME-II) acute MI trials. RESULTS: The frequency of symptomatic recurrent MI during the index hospitalization was 4.2% (836/20,101). Recurrent MI during the index hospital period was associated with increased 30-day mortality (16.4% [137/836] vs. 6.2% [1,188/19,260], p < 0.001). Likewise, recurrent MI was associated with a sustained increase in mortality up to two years, even after adjustments were made for covariates known to be associated with mortality and recurrent MI (hazard ratio 2.11, p < 0.001). However, this higher mortality at 2 years was due to an early divergence in mortality by 30 days and was not due to a significant increase in late mortality between 30 days and 2 years (4.38% [31/707] vs. 3.76% [685/18,206], p = NS). Percutaneous coronary intervention during the index hospitalization was associated with a lower rate of in-hospital recurrent MI (1.6% vs. 4.5%, p < 0.001) and lower two-year mortality (5.6% vs. 11.6%, p < 0.001). Performance of coronary artery bypass graft surgery was also associated with a lower recurrent rate of MI (0.7% vs. 4.3%, p < 0.001) and lower two-year mortality rate (7.95% vs. 10.6%, p = 0.0008). CONCLUSIONS: Early recurrent MI is associated with increased mortality up to two years. However, most deaths occur early, and the risk of additional deaths between the index hospital period and two years was not significantly increased among patients with recurrent MI. Percutaneous coronary intervention during the index hospitalization was associated with a lower risk of recurrent MI and a lower risk of two-year mortality. 相似文献
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Gabriele C. DeLuca Richard L. Yates Harry Beale Sarah A. Morrow 《Brain pathology (Zurich, Switzerland)》2015,25(1):79-98
Cognitive impairment is a common and debilitating feature of multiple sclerosis (MS) that has only recent gained considerable attention. Clinical neuropsychological studies have made apparent the multifaceted nature of cognitive troubles often encountered in MS and continue to broaden our understanding of its complexity. Radiographic studies have started to decipher the neuroanatomic substrate of MS‐related cognitive impairment and have shed light onto its pathogenesis. Where radiographic studies have been limited by inadequate resolution or non‐specificity, pathological studies have come to the fore. This review aims to provide an overview of the nature of cognitive impairment typically seen in MS and to explore the literature on imaging and pathological studies relevant to its evolution. In particular, the relative contributions of gray (ie, cerebral cortex, hippocampus, thalamus and basal ganglia) and white matter to MS‐related cognitive impairment will be discussed and the importance of interconnectivity between structures highlighted. The pressing need for longitudinal studies combining standardized neuropsychometric, paraclinical and radiographic outcomes obtained during life with post‐mortem tissue analysis after death is presented. 相似文献
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Giugliano RP Sabatine MS Gibson CM Roe MT Harrington RA Murphy SA Morrow DA Antman EM Braunwald E 《The American journal of cardiology》2004,93(11):1362-7, A5-6
The restoration of epicardial and myocardial flow remains the primary goal of reperfusion therapy in patients with ST-segment elevation myocardial infarction, but the optimal method to assess this goal has not been defined. Thrombolysis In Myocardial Infarction flow grade (TFG), myocardial perfusion grade (MPG), and ST-segment resolution (STRes) were combined to formulate a new measure of successful reperfusion in 649 patients who received pharmacologic reperfusion therapy in 3 recent phase II clinical trials of ST-segment elevation myocardial infarction. Coronary angiograms and electrocardiograms were analyzed at 60 minutes (before any intervention) after the initiation of reperfusion therapy. The complete restoration of perfusion, or the "trifecta," defined as the presence of TFG 3, MPG 3, and complete (> or =70%) STRes, occurred in 117 patients (18%). The achievement of this trifecta was associated with low rates of 30-day mortality (0% vs 3.9%, p = 0.02), congestive heart failure (CHF) (0.9% vs 7.1%, p = 0.01), and the combination of death or CHF (0.9% vs 10.7%, p = 0.001). When the results were stratified with respect to subsequent percutaneous coronary intervention (PCI) from 60 to 120 minutes, attainment of the trifecta at 60 minutes remained a strong predictor of better clinical outcomes, particularly in those patients who underwent early PCI. The achievement of TFG 3, MPG 3, and complete STRes at 60 minutes after fibrinolytic therapy and before PCI occurred in only 18% of patients but was associated with very low rates of death and CHF at 30 days. This new end point is proposed to evaluate the success of reperfusion therapy in patients who undergo early angiography. 相似文献