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221.
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Methionine (Meth) is an essential amino acid involved in DNA methylation and glutathione biosynthesis. We examined the effect of Meth on the development of steatohepatitis. Rats were fed (five weeks) amino acid-based Meth-choline-sufficient (A-MCS) or total deficient (MCD) diets and gavaged daily (two weeks) with vehicle (B-vehicle/MCD), or Meth replacement (C-Meth/MCD). To assess the effect of short-term deficiency, after three weeks one MCS group was fed a deficient diet (D-MCS/MCD). Animals fed the deficient diet for two weeks lost (29%) weight and after five weeks weighed one third as much as those on the sufficient diet, and also developed anemia (P < 0.01). Hepatic transaminases progressively increased from two to five weeks (P < 0.01), leading to severe hepatic pathology. Meth administration normalized hematocrit, improved weight (P < 0.05), and suppressed abnormal enzymes activities (P < 0.01). Meth administration improved blood and hepatic glutathione (GSH), S-adenosylmethionine (SAMe), and hepatic lesions (P < 0.01). The deficient diet significantly upregulated proinflammatory and fibrotic genes, which was ameliorated by Meth administration. These data support a pivotal role for methionine in the pathogenesis of the dietary model of Meth-choline-deficient (MCD) steatohepatitis (NASH).  相似文献   
223.

Introduction and objectives

To study the prognostic value of serum lactate in patients under temporary preoperative mechanical circulatory support who underwent urgent heart transplant.

Methods

We conducted a subanalysis of a Spanish multicenter registry recording data on patients under temporary mechanical circulatory support listed for highly urgent heart transplant from 2010 to 2015. Participants selected for the present study were those who received a transplant and who had known preoperative serum lactate levels. The main study outcome was 1-year survival after transplant.

Results

A total of 177 heart transplant recipients were studied; preoperatively, 90 were supported on venoarterial extracorporeal membrane oxygenation, 51 on temporary left ventricular assist devices, and 36 on temporary biventricular assist devices. Preoperative hyperlactatemia (≥ 2 mmol/L) was present in 44 (25%) patients. On multivariable analysis, pretransplant serum lactate was identified as an independent predictor of 1-year posttransplant survival (adjusted HR per 0.1 mmol/L, 1.02; 95%CI, 1.01-1.03; P = .007). One-year posttransplant survival was 53.1% (95%CI, 45.3-60.9) in patients with preoperative hyperlactatemia and 75.6% (95%CI, 71.8-79.4) in those without preoperative hyperlactatemia (adjusted HR, 1.94; 95%CI, 1.04-3.63; P = .039). Preoperative hyperlactatemia correlated with adverse outcomes in patients supported with extracorporeal membrane oxygenation, but not in patients supported on ventricular assist devices.

Conclusions

Preoperative serum lactate is a strong independent predictor of worse outcomes in patients undergoing urgent heart transplant on short-term mechanical circulatory support.  相似文献   
224.
目的:为寻找采集外周血造血干细胞更合适的手段,探讨间断流动式血细胞分离机采集外周血造血干细胞的效果。方法:选择中山大学第五附属医院血液风湿科2004-2006年12例行外周血造血干细胞移植住院患者。①实验对象:供者5例,男1例,女4例,一般状况良好,与患者关系为同胞妹妹3例,同胞弟弟1例,同胞姐姐1例;患者7例,男3例,女4例,23~62岁,7例为自体移植,5例为异基因移植。血液系统疾病患者9例(非霍奇淋巴瘤3例,急性淋巴细胞白血病2例,急性髓细胞白血病2例,慢性粒细胞白血病1例,骨髓增生异常综合征1例);自身免疫性疾病3例(重型系统性红斑狼疮2例,难治复发性类风湿关节炎合并干燥综合征1例)。②实验过程:每位供/患者均知情同意并签署知情同意书。对于自体患者,根据患者的疾病类型采取不同的干细胞动员化疗方案,联合化疗后7~10d,待白细胞下降至最低点,一般为≤1.0×109 L-1时,给予粒细胞集落刺激因子5μg/kg皮下注射,白细胞升至3.0×109 L-1时开始采集;对于allo-PBSCT供者直接给予粒细胞集落刺激因子5μg/kg,皮下注射,1次/d,共5d,同时应用流式细胞仪检测CD34 细胞数,至白细胞升至≥20.0×109 L-1或当CD34 细胞升高>20个/μL时采用增强型多功能血细胞分离机PBSC程序卡采集健康供者和患者外周血造血干细胞。③实验评估:分析采集效率、血液学参数、不良事件发生率、以及供、受者ABO血型不合的患者回输干细胞溶血反应等情况。结果:12例供者、患者均进入结果分析。①共进行了24次采集,其中1次采集1例,2次采集7例,3次采集3例,平均循环次数(25±5)次,采集时间(228±32)min,处理血量(7234±1205)mL,复方枸橼酸钠溶液用量为(623±96)mL,干细胞收集量为(102±21)mL,CD34 细胞采集效率为(54.3±30.7)%,细胞计数示白细胞为(156±34)×109 L-1,单个核细胞为(79.7±13.2)×109 L-1,流式细胞仪检测CD34 细胞为(10.30±4.38)×106/kg受者体质量。②不良反应轻微,24次采集过程中出现不良反应6次均为枸橼酸盐所致低钙血症反应。血红蛋白和血小板与采集前相比分别下降9.36%和11.10%。供、受者ABO血型不合的3例患者在输注造血干细胞悬液后均未出现溶血反应。③12例均获造血功能重建,无移植相关死亡。结论:用间断流动式血细胞分离机采集外周血造血干细胞效果良好,不良反应轻微,能有效的减少被采集者红细胞、血小板的丢失,对供、受者ABO血型不合者不需去除造血干细胞悬液中的红细胞,值得临床应用。  相似文献   
225.
《Clinical neurophysiology》2014,125(8):1545-1555
ObjectiveIn the present study, we searched for resting-EEG biomarkers that distinguish different levels of consciousness on a single subject level with an accuracy that is significantly above chance.MethodsWe assessed 44 biomarkers extracted from the resting EEG with respect to their discriminative value between groups of minimally conscious (MCS, N = 22) patients, vegetative state patients (VS, N = 27), and – for a proof of concept – healthy participants (N = 23). We applied classification with support vector machines.ResultsPartial coherence, directed transfer function, and generalized partial directed coherence yielded accuracies that were significantly above chance for the group distinction of MCS vs. VS (.88, .80, and .78, respectively), as well as healthy participants vs. MCS (.96, .87, and .93, respectively) and VS (.98, .84, and .96, respectively) patients.ConclusionsThe concept of connectivity is crucial for determining the level of consciousness, supporting the view that assessing brain networks in the resting state is the golden way to examine brain functions such as consciousness.SignificanceThe present results directly show that it is possible to distinguish patients with different levels of consciousness on the basis of resting-state EEG.  相似文献   
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