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目的研究五味子醇甲(SCH)对APP/PS1双转基因痴呆小鼠行为学和NF-κB p65的影响。方法将35只APP/PS1双转基因痴呆小鼠随机分为模型(APP/PS1)组、五味子醇甲(SCH+APP/PS1)组;另以同背景同月龄的C 57 BL/6 J阴性小鼠为空白(WT)组。SCH+APP/PS1组给予SCH悬浊液灌胃(2.6 mg·kg^-1·d^-1),模型组和空白组给予等量蒸馏水灌胃。各组灌胃30 d进行Mirror水迷宫空间探索试验后取材。HE染色法观察皮层及海马CA1区神经细胞的形态结构。运用DCFH-DA法检测脑组织活性氧(ROS)含量。Western印迹检测法检验磷酸化核转录因子(NF-κB p65,pp65)的表达。结果与APP/PS 1组相比,APP/PS 1+SCH组有效区停留距离及时间明显延长,差异有统计学意义(P<0.05,P<0.01);APP/PS 1+SCH组穿越有效区次数和平台区停留距离增加,均差异有统计学意义(P<0.01)。APP/PS 1+SCH组HE染色观察皮层有部分神经细胞萎缩、减少,较APP/PS1组明显好转,海马细胞排列整齐度尚可、较均匀。与APP/PS1组相比,APP/PS1+SCH组能降低ROS含量,差异有统计学意义(P<0.05)。APP/PS 1+SCH组皮层及海马pp65蛋白相对表达量下调(P<0.05,P<0.01)。结论SCH可能通过降低ROS含量和抑制pp65保护脑组织形态结构和提高APP/PS1鼠空间探索记忆能力。  相似文献   
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Colorectal cancer (CRC) is one of the top three most deadly cancers despite using chemotherapy based on oxaliplatin or irinotecan combined with targeted therapy. Chiauranib has recently been identified to be a promising anticancer candidate with impressive efficacy and safety. However, the role and molecular mechanisms of Chiauranib in the treatment of CRC remain to be elucidated. Our study shows that Chiauranib inhibits cell proliferation and induces apoptosis in KRAS wild-type CRC cells in a dose- and time-dependent manner, but not mutation ones. Meanwhile, Chiauranib increases ROS production in KRAS wild-type CRC cells. Moreover, Chiauranib selectively suppresses KRAS wild-type CRC cells growth in vivo. Mechanistically, Chiauranib inhibits KRAS wild-type CRC cells by triggering ROS production via activating the p53 signaling pathway. Further, KRAS mutation CRC cells are resistant to Chiauranib by increasing Nrf2 to stably elevate the basal antioxidant program and thereby lower intracellular ROS induced by Chiauranib. Our findings provide the rationale for further clinical evaluation of Chiauranib as a therapeutic agent in treating KRAS wild-type CRC.  相似文献   
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Background

Acute myocardial infarction (AMI) causes irreversible myocardial damage and release of inflammatory mediators, including cytokines, chemokines and miRNAs. We aimed to investigate changes in the levels of cytokines (IL-6, TNF-α and IL-10), miRNAs profiles (miR-146 and miR-155) and distribution of different monocyte subsets (CD14++CD16-, CD14++CD16+, CD14+CD16++) in the acute and post-healing phases of AMI.

Methods

In eighteen consecutive AMI patients (mean age 56.78?±?12.4 years, mean left ventricle ejection fraction – LVEF: 41.9?±?9.8%), treated invasively, monocyte subsets frequencies were evaluated (flow cytometry), cytokine concentrations were analyzed (ELISA) as well as plasma miRNAs were isolated twice – on admission and after 19.2?±?5.9 weeks of follow-up. Measurements were also performed among healthy volunteers.

Results

AMI patients presented significantly decreased frequencies of classical cells in comparison to healthy controls (median 71.22% [IQR: 64.4–79.04] vs. 84.35% [IQR: 81.2–86.7], p?=?0.001) and higher percent of both intermediate and non-classical cells, yet without statistical significance (median 6.54% [IQR: 5.14–16.64] vs. 5.87% [IQR: 4.48–8.6], p?=?0.37 and median 5.99% [IQR: 3.39–11.5] vs. 5.26% [IQR: 3.62–6.2], p?=?0.42, respectively). In AMI patients both, analyzed plasma miRNA concentrations were higher than in healthy subjects (miR-146: median 5.48 [IQR: 2.4–11.27] vs. 1.84 [IQR: 0.87–2.53], p?=?0.003; miR-155: median 25.35 [IQR: 8.17–43.15] vs. 8.4 [IQR: 0.08–16.9], p?=?0.027, respectively), and returned back to the values found in the control group in follow-up. miR-155/miR-146 ratio correlated with the frequencies of classical monocytes (r=0.6, p?=?0.01) and miR-155 correlated positively with the concentration of inflammatory cytokines ? IL-6 and TNF-α.

Conclusions

These results may suggest cooperation of both pro-inflammatory and anti-inflammatory signals in AMI in order to promote appropriate healing of the infarcted myocardium.  相似文献   
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Patients with non‐small cell lung cancer (NSCLC) containing ROS1 fusions can have a marked response to the ROS1‐targeted tyrosine kinase inhibitors (TKIs), such as crizotinib. Common resistance mechanisms of ROS1‐fusion targeted therapy are acquired mutations in ROS1. Along with the use of next‐generation sequencing in the clinical management of patients with NSCLC during sequential targeted therapy, many mechanisms of acquired resistance have been discovered in patients with activated tyrosine kinase receptors. Besides acquired resistance mutations, bypass mechanisms of resistance to epidermal growth factor receptor (EGFR)‐TKI treatment are common in patients with EGFR mutations. Here we describe a patient with metastatic lung adenocarcinoma with CD74‐ROS1 fusion who initially responded to crizotinib and then developed resistance by the acquired mutation of D1228N in the MET kinase domain, which showed short‐term disease control for cabozantinib.Key Points
  • The D1228N point mutation of MET is an acquired mutation for crizotinib resistance.
  • The patient obtained short‐term clinical benefit from cabozantinib therapy after resistance to crizotinib.
  • The clinical use of next‐generation sequencing could maximize the benefits of precision medicine in patients with cancer.
  相似文献   
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