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1.
[摘要]?微小RNA (microRNA, miRNA)在宿主-病毒相互作用中起关键调节作用,参与HBV感染、复制和HBV相关疾病的调节。细胞miRNA可以通过直接结合HBV转录物或通过靶向与HBV生命周期相关的细胞因子间接调节HBV转录和复制。反过来,HBV感染也可以影响宿主细胞内的miRNA水平。HBV和miRNA之间的相互作用在HBV复制和HBV相关疾病的发病机制中发挥重要作用。本文对miRNA与HBV的相互关系进行综述,为进一步探讨HBV感染致病的分子机制和开发新的抗HBV治疗策略提供参考。  相似文献   
2.
Mixed lineage leukemia 1(MLL1)是组蛋白甲基转移酶SET家族的成员之一。MLL1与WDR5、RbBP5、Ash2L和DPY-30组成MLL1甲基转移酶复合物调控组蛋白H3的第4位赖氨酸的甲基化水平,对造血系统的发育和血细胞的更新至关重要。部分白血病患者体内存在因MLL1基因易位而产生的致癌蛋白——MLL1融合蛋白,MLL1融合蛋白在发挥其致癌作用时需要功能完整的MLL1酶复合物,故靶向MLL1-WDR5的蛋白-蛋白相互作用成为治疗MLL1融合型白血病的潜在策略。本文对MLL1-WDR5蛋白-蛋白相互作用的生物学机制、结构信息以及抑制剂进行了系统的总结,并结合已报道数据对该领域进行了展望,以期为后续研究提供参考。  相似文献   
3.
Objective: Cancer is a huge problem of disease globally. Today, the percentage of people die from cancer is more than a combination of various diseases. In females, most common types of malignancies that occur are breast and cervical. The present focus has been shifted on medicinal plants as a form of therapy and there is a constant need to identify new therapeutic agents. Choerospondias axillaris (C. axillaris), an underutilized fruit, has been used in the remedy of various diseases. In the present communication, we evaluated the molecular mechanism of C. axillaris methanol extract in regulating cell death in human breast cancer cells (MDA-MB-231). Methods: Methanol extract of C. axillaris was prepared and compounds were screened by Gas chromatography-mass spectrometry. The effect of fruit extract was determined on MDA-MB-231 cells by MTT ((3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay and to analyse the molecular mechanism of human breast cancer cells after treating with fruit extract, protein profiling study was performed by two-dimensional gel electrophoresis. Results: A total 9 differentially expressed proteins were identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF-MS/MS) analysis. Among 9 identified proteins, synphilin-1 protein was found to be significantly downregulated, validated by western blot and RT-qPCR analysis. Possible interacting partners of synphilin-1 (SNCAIP) were analyzed for their possible role in cancer by the in-silico method. Conclusion: Our data implicate that the presence of bioactive compound(s) in C. axillaris fruits might play an important role in inhibiting the proliferation of breast carcinoma cells and Synphilin-1 protein may play a role of apoptotic function.  相似文献   
4.
《Immunobiology》2022,227(6):152298
PLPPs (Phospholipid phosphatases) are widely expressed in different human tissues, regulate cell signal transduction, and are overexpressed in cancers such as gliomas, pancreatic adenocarcinoma, lung adenocarcinoma, and so on. As a member of the PLPP family, PLPP2 (phospholipid phosphatase 2) plays a vital role in the occurrence and development of breast cancer, but its mechanism is still unclear. Our research found that PLPP2 was overexpressed in breast cancer, and the higher expression level of PLPP2 showed a worse prognosis for breast cancer patients. Further analysis showed that overexpression of PLPP2 affected the expression of CDC34 (cell-division cycle 34), LSM7 (Like-Smith 7), and SGTA (small glutamine-rich tetratricopeptide repeat-containing protein alpha) through EMT (epigenetic-mesenchymal transition) related pathways to promote the occurrence and development of breast cancer. In vitro, silencing PLPP2 significantly reduced the proliferation, invasion, and migration abilities of human breast cancer cells MDA-MB-231. ER+ is a common subtype of breast cancer. Furthermore, we found that the overexpression of PLPP2 was significantly related to the poor prognosis of ER+ breast cancer. These results indicate that PLPP2 has value as a potential therapeutic target for breast cancer, especially for ER+ breast cancer.  相似文献   
5.
《Saudi Pharmaceutical Journal》2022,30(11):1572-1588
Non-alcoholic fatty liver disease (NAFLD) is one of the most common complications of a metabolic syndrome caused by excessive accumulation of fat in the liver. Orthosiphon stamineus also known as Orthosiphon aristatus is a medicinal plant with possible potential beneficial effects on various metabolic disorders. This study aims to investigate the in vitro inhibitory effects of O. stamineus on hepatic fat accumulation and to further use the computational systems pharmacology approach to identify the pharmacokinetic properties of the bioactive compounds of O. stamineus and to predict their molecular mechanisms against NAFLD. Methods: The effects of an ethanolic extract of O. stamineus leaves on cytotoxicity, fat accumulation and antioxidant activity were assessed using HepG2 cells. The bioactive compounds of O. stamineus were identified using LC/MS and two bioinformatics databases, namely the Traditional Chinese Medicine Integrated Database (TCMID) and the Bioinformatics Analysis Tool for the Molecular Mechanism of Traditional Chinese Medicine (BATMAN-TCM). Pathway enrichment analysis was performed on the predicted targets of the bioactive compounds to provide a systematic overview of the molecular mechanism of action, while molecular docking was used to validate the predicted targets. Results: A total of 27 bioactive compounds corresponding to 50 potential NAFLD-related targets were identified. O. stamineus exerts its anti-NAFLD effects by modulating a variety of cellular processes, including oxidative stress, mitochondrial β-oxidation, inflammatory signalling pathways, insulin signalling, and fatty acid homeostasis pathways. O. stamineus is significantly targeting many oxidative stress regulators, including JNK, mammalian target of rapamycin (mTOR), NFKB1, PPAR, and AKT1. Molecular docking analysis confirmed the expected high affinity for the potential targets, while the in vitro assay indicates the ability of O. stamineus to inhibit hepatic fat accumulation. Conclusion: Using the computational systems pharmacology approach, the potentially beneficial effect of O. stamineus in NAFLD was indicated through the combination of multiple compounds, multiple targets, and multicellular components.  相似文献   
6.
目的探究昼夜节律基因对红花黄酮类物质生物合成的影响及机制。方法基于红花花冠转录组及代谢组数据库筛选潜在调控红花黄酮类化合物生物合成的昼夜节律基因;用qPCR测定红花各部位以及花冠单日不同时间点昼夜节律基因的表达量,液质联用测定黄酮类化合物的积累量,并分析二者的相关性;酵母双杂交实验验证昼夜节律基因的互作蛋白。结果获得7个昼夜节律基因PRR1、PRR2、ELF3、FT、PHYB、GI、ZTL,其中PRR1基因与黄酮类化合物积累量呈正相关(r≥0.7)。PRR1全长3201 bp,编码421个氨基酸,与水稻OsPRR73基因高度同源,将其命名为CtPRR1(GenBank登录号:MW492035)。CtPRR1主要在花中表达,表达量在日间逐渐升高,晚间逐渐下降;黄酮类化合物芹菜素、槲皮素、HSYA、山奈酚、Carthamin、山奈酚-3-O-葡萄糖苷以及野黄芩素的含量为白天逐渐降低,晚间逐渐升高,二者都有昼夜节律性且呈负相关(r≥?0.7)。酵母双杂实验得到2个热休克蛋白、3个AP2转录因子。结论CtPRR1对红花黄酮类成分的昼夜节律性积累起负调节作用;CtPRR1可能受这些互作蛋白的影响调控红花黄酮类成分的昼夜节律性积累。  相似文献   
7.
目的 了解糖尿病患者对糖尿病与牙周病相互作用的认知、态度及保健行为的现状,探讨并分析其影响因素,为糖尿病患者的口腔与全身健康治疗方案及口腔健康宣教计划制订提供依据。方法 2021年4—5月采用便利抽样方法,对济宁市内三级甲等医院和二级甲等医院各两家的内分泌科病房和门诊的糖尿病患者进行调查,共获得232份有效问卷。内容包括糖尿病患者的一般情况、保健行为、对糖尿病与牙周病相互作用的认知情况、对糖尿病并发牙周病的治疗态度及其影响因素。结果 232名糖尿病患者对糖尿病与牙周病的相互作用的认知、治疗态度和保健行为的总得分为(39.42±18.23)分,小学及以下学历者平均得分最低为(28.69±12.04)分,年龄≥60岁者平均得分最低为(34.10±16.27)分;单因素分析显示,糖尿病患者保健行为、认知、治疗态度得分在不同婚姻状况、年龄、文化程度等方面,差异有统计学意义(P<0.05);Pearson线性相关性分析显示,糖尿病患者的认知与保健行为、认知与治疗态度、治疗态度与保健行为的得分呈正相关;多重线性回归分析显示,年龄、家庭人均月收入、文化程度、有牙周病和无牙周病进入模型(P<0.01),共解释总变异的36.6%。结论 本次调查中,糖尿病患者对糖尿病与牙周病的相互作用的认知、治疗态度和保健行为三者之间相互影响,不同特征的糖尿病患者得分水平不同,年龄、文化程度和家庭人均月收入等因素是影响其得分的主要因素,应加强对高龄糖尿病患者的关注,积极对糖尿病患者开展口腔预防保健工作。  相似文献   
8.
《Drug discovery today》2022,27(1):82-101
WNT/β-catenin signaling orchestrates various physiological processes, including embryonic development, growth, tissue homeostasis, and regeneration. Abnormal WNT/β-catenin signaling is associated with various cancers and its inhibition has shown effective antitumor responses. In this review, we discuss the pathway, potential targets for the development of WNT/β-catenin inhibitors, available inhibitors, and their specific molecular interactions with the target proteins. We also discuss inhibitors that are in clinical trials and describe potential new avenues for therapeutically targeting the WNT/β-catenin pathway. Furthermore, we introduce emerging strategies, including artificial intelligence (AI)-assisted tools and technology-based actionable approaches, to translate WNT/β-catenin inhibitors to the clinic for cancer therapy.  相似文献   
9.
目的分析基于表面肌电图人体运动意图识别的研究方法和识别效果。  相似文献   
10.
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