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1.
目的 对比研究朝鲜淫羊藿酸性多糖酯化还原前后的理化特性,并探讨其改善油酸诱导的肝癌HepG2细胞脂质堆积活性的差异。方法 采用高效凝胶渗透色谱法测定朝鲜淫羊藿酸性多糖(EFPA)的均一性和分子量,高效液相色谱法测定EFPA和酯化还原后朝鲜淫羊藿酸性多糖(EFPA-R)的单糖组成;采用油酸(OA)处理HepG2细胞诱导建立脂质蓄积模型,不同浓度EFPA与EFPA-R(10、30、100、300 μg·mL-1)分别和OA共同作用于细胞24 h,采用CCK-8试剂盒测定细胞存活率,油红O染色观察细胞内脂滴蓄积情况,并采用试剂盒测定细胞内总胆固醇(TC)、甘油三酯(TG)含量。结果 EFPA为成分均一的多糖组分,分子量为125.8 kDa,由甘露糖、葡萄糖、半乳糖、葡萄糖醛酸和阿拉伯糖组成,摩尔比为1.7∶7.4∶1.4∶1.8∶1.0,葡萄糖占比最大,EFPA-R由甘露糖、葡萄糖、半乳糖和阿拉伯糖组成,摩尔比为0.8∶10.6∶2.1∶1.0;在10-300 μg·mL-1范围内,EFPA和EFPA-R对HepG2细胞的抑制作用较弱,作为给药浓度;与空白组相比,模型组细胞中TC、TG含量显著升高(P < 0.01),细胞内红色脂滴显著增多,与模型组相比,EFPA可显著降低细胞中TC、TG含量(P < 0.01),明显减少细胞内红色脂滴(P < 0.05或P < 0.01),EFPA-R干预后细胞则无明显变化。结论 EFPA可明显改善HepG2细胞脂质堆积情况,且呈现剂量依赖性,而半乳糖醛酸(GalA)的存在可能是其抑制HepG2细胞脂质蓄积的关键因素。 相似文献
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Ludefu Su Yu Liu Yanhong Tang Mingmin Zhou Liang Xiong Congxin Huang 《International journal of clinical and experimental pathology》2021,14(4):408
Background and objective: Myocardial infarction (MI) is a common critical disease of the cardiovascular system. The process of MI is often accompanied by the excessive activation of cardiac sympathetic nerves, which leads to arrhythmia. Resiniferatoxin (RTX) is a transient receptor potential vanilloid 1 (TRPV1), involved in the cardiac sympathetic afferent reflex. However, whether RTX can reduce the occurrence of arrhythmia and exert a cardioprotective effect by inhibiting the sympathetic reflex during MI is still unknown. Methods: The left anterior descending artery of cardiac was clamped to construct a model of MI. RTX (50 μg/ml) was used by epicardial application in MI rats. Ventricular electrophysiologic properties were continuously monitored by a body surface ECG. Yrosine hydroxylase (TH) and growth associated protein 43 (GAP43) were detected by Immunofluorescence staining. Connexin43 and transforming growth factor beta receptor 1 (TGF-β1) were detected by western blot. Norepinephrine (NE) and BNP levels in blood and tissue were determined by ELISA. Cardiac function was assessed by echocardiography. Results: The ERP, APD90, QRS, QT and the Tend-Tpeak intervals in MI rats were all prolonged, but decreased after RTX treatment (n = 3, P<0.05). In contrast, the RR interval was shortened in the MI group, but prolonged in the MI+RTX group (n = 3, P<0.05). RTX treatment significantly reduced ventricular arrhythmias after MI. TH- and GAP43-positive nerve densities and TGF-β1, and cx-43 protein expression were up-regulated in the MI group compared to the sham group, and they were decreased in the MI+RTX group compared to the MI group (n = 3, P<0.05). RTX can decrease serum and tissue NE and BNP levels (n = 3, P<0.05). RTX pretreatment significantly decreased heart rate, HW/BW ratio and LVIDS, and increased LVEF andLVFS values (n = 3, P<0.05). Conclusion: RTX improved cardiac dysfunction, ventricular electrophysiologic properties, and sympathetic nerve remodeling in rats with MI by inhibiting the excessive cardiac sympathetic drive. 相似文献
3.
Lei Yang You-Ling Shi Yan Ma Wei-Wei Ren Guang-Ming Pang Jiao Liu 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2022,130(1):43-52
Krüppel-like factor 16 (KLF16), a member of the Krüppel-like factor (KLF) family, has been extensively investigated in multiple cancer types. However, the role of KLF16 in oral squamous cell carcinoma (OSCC) remains unknown. Thus, we conducted this study to investigate its related mechanism. KLF16 expression in OSCC cell lines was quantified by western blotting. Then, OECM1 and OC3 cells were divided into Blank, siCtrl, siKLF16#1 and siKLF16#2 groups. Subsequently, cell proliferation was detected using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assays, cell migration and invasion were detected with wound healing and Transwell assays, and cell cycle distribution and cell apoptosis were detected via flow cytometry. KLF16, p21, CDK4, Cyclin D1 and p-Rb expression was detected by western blotting. Finally, xenograft models were established in nude mice to observe the in vivo effects of KLF16 on OSCC. KLF16 protein expression was upregulated in OSCC cells. Compared to the cells in the Blank group, the OECM1 and OC3 cells in the siKLF16#1 group and siKLF16#2 group exhibited a sharp decrease in proliferation but a remarkable increase in apoptosis. Moreover, the proportion of cells in the G0/G1 phase notably increased and that in the S phase decreased, with evident decreases in cell invasion and migration. Moreover, KLF16, cyclin-dependent kinase 4 (CDK4), Cyclin D1 and p-Rb protein expression was upregulated, but p21 expression was downregulated. The mice in the siKLF16#1 and siKLF16#2 xenograft model groups exhibited slower tumour growth and smaller tumours with evident downregulation of Ki67 expression compared to the mice in the Blank group. KLF16 expression was upregulated in OSCC cells, and interfering with KLF16 led to cell cycle arrest, inhibited OSCC cell growth and promoted cell apoptosis. 相似文献
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Yinlei
Wen Huaguang Zhang Hanguang Su He Ren 《Optimal control applications & methods.》2020,41(4):1233-1250
In this article, a model-free off-policy reinforcement learning algorithm is applied to address the optimal tracking problem based on multiplayer non-zero-sum games for discrete-time linear systems. In contrast to the traditional method and the policy iteration method for solving the optimal tracking problems, the proposed algorithm operates with the system data rather than the knowledge of the system dynamics. For performing the proposed algorithm, an auxiliary augmented system is constructed via assembling the original system and the reference trajectory while a discount factor is introduced into the performance indexes. It is analyzed that the solutions of the proposed algorithm converge to the Nash equilibrium and the result is not influenced by the probing noise. Two simulations are presented to verify the feasibility and effectiveness of the proposed algorithm. 相似文献
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目的评估血肌酐和尿常规的常规检测基础上联合血清胱抑素C和尿微量白蛋白检测在人类免疫缺陷病毒(HIV)感染者肾功能损伤检测中的应用价值。
方法以2019年2~5月于首都医科大学附属北京地坛医院感染一科住院的169例HIV感染者为研究对象,完善其尿常规、尿微量白蛋白、血肌酐、血清胱抑素C检测;分析尿蛋白及尿微量白蛋白的阳性检出率及其差异,血肌酐升高及血清胱抑素C升高的比例及其差异。计算应用替诺福韦酯(TDF)及合并丙型肝炎、高血压、糖尿病、肿瘤的肾功能损伤的相对危险度。
结果169例HIV感染者中尿常规示尿蛋白阳性者5例(3.0%),尿微量白蛋白升高者17例(10.1%),两者阳性检出率差异具有统计学意义(χ2 = 5.9、P = 0.007)。血肌酐升高者10例(5.9%),血清胱抑素C升高者20例(11.8%),两者阳性检出率差异具有统计学意义(χ2 = 3.0、P = 0.042)。在尿常规和血肌酐检测的基础上联合检测尿微量白蛋白和血清胱抑素C的总体阳性检出率为49例(30.0%)。CD4+ T淋巴细胞计数< 200个/μl与≥ 200个/μl组患者血清胱抑素C水平分别为0.94(0.83,1.05)mg/L、0.85(0.77,0.95)mg/L,差异具有统计学意义(Z =-3.02、P = 0.003)。应用TDF及合并丙型肝炎、高血压、糖尿病、肿瘤的肾功能损伤的相对危险度分别为1.1、1.5、1.9、2.2和1.4。
结论HIV感染者中,单纯以尿常规为依据评估有无蛋白尿,以血肌酐水平为依据评估肾小球滤过功能会低估肾功能损伤的患病率。在常规检测血肌酐和尿常规的基础上联合检测血清胱抑素C和尿微量白蛋白在提高HIV感染者肾功能损伤检出率方面具有重要的应用价值。低CD4+ T淋巴细胞计数、应用TDF及合并丙型肝炎、高血压、糖尿病、肿瘤均为肾功能损伤的危险因素。 相似文献
9.
仝小林院士将新型冠状病毒肺炎定名为"寒湿疫",并以此理论为基础制定了初期、中期、重症期及恢复期的中医治疗方案,同时基于仝院士学术理论体系中的"脏腑风湿"理论,根据恢复期 "余毒未清,正虚邪恋"的病机特点,探讨其符合具备脏腑风湿行成3个基本要素:即外受寒湿裹挟戾气为必要外因;脏腑内虚为重要基础;邪疫伏留胶着,正邪交争为致病关键。故在辨证施治中可应用脏腑风湿理论以调理脾胃,化湿透邪,补益肺脾,顾护阳气,养阴生津。 相似文献
10.
文题释义:肱骨近端骨折:肱骨近端包括肱骨头及大结节、小结节,中老年人骨质疏松及低能量损伤可导致肱骨近端骨折。
同种异体腓骨:取自于人体异体,经过加工处理,去除其免疫原性,保留其骨性结构,可用于移植修复骨缺损,起到支撑作用。
背景:肱骨近端骨折是临床常见骨折,但对肱骨近端内侧柱缺乏支撑的骨折目前仍是治疗难点,并发症常见,失败率较高。
目的:比较解剖锁定钢板联合同种异体腓骨与单纯解剖锁定钢板治疗肱骨近端骨折的疗效。
方法:使用计算机检索PubMed、Embase、Cochrane Library、Google Scholar、中国知网、万方、维普数据库,检索时间均从建库到2020年2月。检索国内外关于对比研究解剖锁定钢板联合同种异体腓骨与单纯解剖锁定钢板治疗肱骨近端骨折疗效的文献。2名研究员根据纳入和排除标准分别独立筛选文献,提取数据,评估文献中的偏倚风险。纳入12篇相关文献使用RevMan 5.2软件将以下指标进行Meta分析,包括影像学数据、功能评分和并发症。结果与结论:①通过文献检索、根据纳入和排除标准,12篇文献纳入研究,其中11篇为回顾性队列研究,1篇为随机对照研究;纳入研究文献质量高,但GRADE证据质量级别较低。②共纳入958例患者,其中解剖锁定钢板联合同种异体腓骨组411例,单纯解剖锁定钢板组547例;③Meta分析结果显示,解剖锁定钢板联合同种异体腓骨组术后1年肱骨头高度差值(MD=-2.40,95%CI:-2.49至-2.31)、颈干角差值(MD= -6.14,95%CI:-6.62至-5.67)、目测类比评分(MD=-0.22,95%CI:-0.35至-0.08)、肩关节功能评分(MD=4.12,95%CI:2.18-6.06),上肢伤残评分(MD=-10.32,95%CI:-13.44至-7.19)、术后2年的目测类比评分(MD=-0.37,95%CI:-0.55至-0.19)、肩关节功能评分(MD=5.07,95%CI:2.86-7.27)、总体并发症(OR=0.31,95%CI:0.20-0.48)及肱骨头螺钉切出(OR=0.25,95%CI:0.11-0.55)均明显优于单纯解剖锁定钢板组(P < 0.05),肱骨头坏死(OR=0.94,95%CI:0.47-1.88),两组间差异无显著性意义(P > 0.05);④因此,较弱的证据提示,肱骨近端解剖锁定钢板联合同种异体腓骨治疗肱骨近端骨折的短期疗效优于解剖锁定钢板,可减少并发症的发生,促进功能恢复。ORCID: 0000-0002-8486-3932(阳运康)
中国组织工程研究杂志出版内容重点:人工关节;骨植入物;脊柱;骨折;内固定;数字化骨科;组织工程 相似文献