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IntroductionThere is no consensus on the most appropriate treatment for chronic active antibody-mediated rejection (cAMR). Recent studies suggest that treatment with tocilizumab (TCZ) may stabilize graft function, decrease the intensity of donor-specific HLA antibodies (DSAs) and reduce inflammation of microcirculation.Patients and methodsObservational study with renal allograft recipients diagnosed with cAMR (n = 5) who had not submitted a response to traditional treatment based on the combination of plasma replacements, immunoglobulins, and rituximab. Patients were told to be treated with TCZ as compassionate use in six doses per month (8 mg/kg/month). Renal function, proteinuria, and the intensity of DSAs were monitored during follow-up.ResultsFive patients, average age 60 ± 13 years, three male and two retrasplants (cPRA average 55%) with preformed DSAs. Treatment with TCZ was initiated within 47 ± 52 days of biopsy. In two cases treatment was discontinued after the first dose, by severe bicitopenia with cytomegalovirus viremia and by graft failure, respectively. In the three patients who completed treatment, no stability of renal function (serum creatinine from 1.73 ± 0.70 to 2.04 ± 0.52 mg/dL, e-FGR 4 6 ± 15 to 36 ± 16 mL/min), showed increased proteinuria (3.2 ± 4.0 to 6.9 ± 11.0 g/g) and the intensity of DSAs maintain stable. No changes were observed in the degree of inflammation of microcirculation (g + pt 4.2 ± 0.8 vs. 4.3 ± 1.0) or in the degree of transplant glomerulopathy (cg 1.2 ± 0.4 vs. 1.8 ± 1.0).ConclusionsTCZ therapy does not appear to be effective in modifying the natural history of chronic active antibody-mediated rejection, does not improve the degree of inflammation of microcirculation and does not reduces the intensity of DSAs.  相似文献   
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Oxidative stress and inflammation are two possible mechanisms related to nephrotoxicity caused by environmental pollutants. Ellagic acid, a powerful antioxidant phytochemical, may have great relevance in mitigating pollutant-induced nephrotoxicity and preventing the progression of kidney disease. This review discusses the latest findings on the protective effects of ellagic acid, its metabolic derivatives, the urolithins, against kidney toxicity caused by heavy metals, pesticides, mycotoxins, and organic air pollutants. We describe the chelating, antioxidant, anti-inflammatory, antifibrotic, antiautophagic, and antiapoptotic properties of ellagic acid to attenuate nephrotoxicity. Furthermore, we present the molecular targets and signaling pathways that are regulated by these antioxidants, and suggest some others that should be explored. Nevertheless, the number of reports is still limited to establish the efficacy of ellagic acid against kidney damage induced by environmental pollutants. Therefore, additional preclinical studies on this topic are required, as well as the development of well-designed clinical trials.  相似文献   
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目的:探索健脾生血片治疗慢性心力衰竭伴贫血的疗效、安全性和作用机制。方法:选取2016年5月至2017年2月同济医院收治的慢性心力衰竭贫血患者144例,按照随机数字表法分为观察组和对照组,每组72例。观察组给予健脾生血片治疗,3片/次,3次/d,疗程3个月;对照组给予生血宝合剂治疗,15 m L/次,3次/d,3个月为1个疗程。比较2组患者治疗前与治疗后血红蛋白、红细胞计数、网织红细胞、血清铁、转铁蛋白饱和度、血清铁蛋白、血清铁调素(Hepcidin)、血清IL-1β、血清肿瘤坏死因子-α(TNF-α)、血清C反应蛋白(CRP)、左室射血分数(LVEF)、6 min步行距离、明尼苏达心力衰竭生命质量量表(MLHFQ)和不良事件。并随访2组心血管事件次数,住院次数与全因死亡率。结果:观察组72例患者完成了前3个月的治疗,随访期间脱失2例;对照组治疗期间1例患者退出研究,随访期间脱失4例。2组一般资料比较,差异无统计学意义(P 0. 05),具有可比性。观察组贫血有效率98. 6%,对照组有效率11. 3%,差异有统计学意义(P0. 05)。治疗后观察组红细胞计数和网织红细胞、均显著高于对照组(P 0. 05)。观察组血清铁、转铁蛋白饱和度水平均高于对照组,差异有统计学意义(P 0. 05),但血清铁调素水平显著低于对照组,差异有统计学意义(P 0. 05),血清铁蛋白水平2组差异无统计学意义(P 0. 05)。观察组IL-1β、血清TNF-α、血清CRP均显著低于对照组,差异有统计学意义(P 0. 05)。观察组LVEF、6 min步行距离、明尼苏达心力衰竭生命质量量表(MLHFQ)均显著高于对照组,差异有统计学意义(P 0. 05)。2组不良事件总发生率比较,差异无统计学意义(P 0. 05),但对照组4例患者出现血清肌酐、尿素氮水平异常,发生率高于观察组,差异有统计学意义(P 0. 05)。经1年随访,观察组心血管事件人均发生次数显著少于对照组(P 0. 05),但2组住院次数和全因死亡率比较,差异无统计学意义(P 0. 05)。结论:健脾生血片可有效治疗心力衰竭伴贫血,减少心血管发生次数,并且安全性良好,其作用机制与提供准确足量铁元素、抑制铁调素表达,抑制慢性炎性反应有关。  相似文献   
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BACKGROUND Postoperative liver failure is the most severe complication in cirrhotic patients with hepatocellular carcinoma(HCC) after major hepatectomy. Current available clinical indexes predicting postoperative residual liver function are not sufficiently accurate.AIM To determine a radiomics model based on preoperative gadoxetic acid-enhanced magnetic resonance imaging for predicting liver failure in cirrhotic patients with HCC after major hepatectomy.METHODS For this retrospective study, a radiomics-based model was developed based on preoperative hepatobiliary phase gadoxetic acid-enhanced magnetic resonance images in 101 patients with HCC between June 2012 and June 2018. Sixty-one radiomic features were extracted from hepatobiliary phase images and selected by the least absolute shrinkage and selection operator method to construct a radiomics signature. A clinical prediction model, and radiomics-based model incorporating significant clinical indexes and radiomics signature were built using multivariable logistic regression analysis. The integrated radiomics-based model was presented as a radiomics nomogram. The performances of clinical prediction model, radiomics signature, and radiomics-based model for predicting post-operative liver failure were determined using receiver operating characteristics curve, calibration curve, and decision curve analyses.RESULTS Five radiomics features from hepatobiliary phase images were selected to construct the radiomics signature. The clinical prediction model, radiomics signature, and radiomics-based model incorporating indocyanine green clearance rate at 15 min and radiomics signature showed favorable performance for predicting postoperative liver failure(area under the curve: 0.809-0.894). The radiomics-based model achieved the highest performance for predicting liver failure(area under the curve: 0.894; 95%CI: 0.823-0.964). The integrated discrimination improvement analysis showed a significant improvement in the accuracy of liver failure prediction when radiomics signature was added to the clinical prediction model(integrated discrimination improvement = 0.117, P =0.002). The calibration curve and an insignificant Hosmer-Lemeshow test statistic(P = 0.841) demonstrated good calibration of the radiomics-based model. The decision curve analysis showed that patients would benefit more from a radiomics-based prediction model than from a clinical prediction model and radiomics signature alone.CONCLUSION A radiomics-based model of preoperative gadoxetic acid–enhanced MRI can be used to predict liver failure in cirrhotic patients with HCC after major hepatectomy.  相似文献   
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2019年12月我国湖北省武汉市爆发新型冠状病毒(2019-nCoV)感染疫情,目前已蔓延至全国各地,流行病学显示人群对该病毒普遍易感,且患有基础疾病的患者是重症、危重症的高危人群,同时儿童青少年感染病例数正日益增多。慢性心力衰竭儿童因其基础条件差,感染2019-nCoV后将给此类患儿的诊治带来严峻的挑战。结合儿童2019-nCoV感染的临床特点及儿童慢性心力衰竭的诊治要点,在此提出慢性心力衰竭儿童2019-nCoV感染的临床管理建议,以供临床参考。  相似文献   
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目的:研究Toll样受体4(TLR4) mRNA及其下游炎性因子肿瘤坏死因子-α(TNF-α)与肝衰竭肠源性内毒素血症(IETM)大鼠肝细胞凋亡的关系,并探索温阳解毒化瘀颗粒对内毒素介导的肝细胞凋亡的调控机制。方法:SPF级雄性SD大鼠85只,随机分为正常组,模型组,TLR4单克隆抗体组和温阳解毒化瘀颗粒组(8.925 g·kg^-1)。采用D-半乳糖胺(D-Gal)腹腔注射建立肝衰竭IETM模型,TLR4单克隆抗体组和温阳解毒化瘀颗粒组在造模前5 d给予温阳解毒化瘀颗粒溶液灌胃,正常组、模型组以等容积蒸馏水代替,直至处死。各组分别在24,48,72 h随机处死大鼠并采集标本。检测24,48,72 h各组时间点血清丙氨酸氨基转移酶(ALT),天门冬氨酸氨基转移酶(AST)水平,苏木素-伊红(HE)染色观察肝组织病理变化,实时荧光定量聚合酶链式反应(Real-time PCR)检测肝组织TLR4 mRNA表达,酶联免疫吸附测定法(ELISA)检测肝组织TNF-α表达,流式细胞仪检测肝细胞凋亡率。结果:与正常组比较,模型组ALT,AST升高,肝组织病理损伤程度明显加重,TLR4mRNA,TNF-α表达均增高(P<0.05,P<0.01),肝细胞凋亡率明显上升(P<0.05,P<0.01);与模型组比较,温阳解毒化瘀颗粒组ALT,AST显著降低(P<0.01),肝组织病理损伤程度明显减轻(P<0.05),TLR4 mRNA,TNF-α表达显著下降(P<0.01),肝细胞凋亡率亦显著降低(P<0.01)。结论:TLR4 mRNA,TNF-α在肝衰竭时与肝细胞凋亡呈正相关,温阳解毒化瘀颗粒能够改善肝衰竭IETM大鼠肝功能,减轻肝细胞损伤,减少肝细胞凋亡,其机制可能与其下调肝脏TLR4 mRNA表达,抑制TNF-α释放,降低肝细胞凋亡率有关。  相似文献   
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