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1.
Targeting the tumor cell mitochondrion could produce novel anticancer agents. We designed an aryl−urea fatty acid ( 1 g ; 16({[4-chloro-3-(trifluoromethyl)phenyl]carbamoyl}amino)hexadecanoic acid) that disrupted the mitochondrion and decreased MDA-MB-231 breast cancer cell viability. To optimize the aryl−ureas the present study evaluated mitochondrial targeting by 1 g analogues containing alkyl chains between 10–17 carbons. Using the dye JC-1, the C12−C17 analogues efficiently disrupted the mitochondrial membrane potential (IC50s 3.5±1.2 to 7.6±1.1 μM) and impaired ATP production; shorter analogues were less active. 7-Aminoactinomycin D/annexin V staining and flow cytometry showed that these agents activated the killing mechanisms of necrosis and apoptosis to varying extents (7-aminoactinomycin D/annexin V staining ratios 4.3–6.0). Indeed, 1 g and its C17 analogue preferentially activated necrosis and apoptosis, respectively (ratios 2.1 and 16). Taken together, alkyl chain length is a determinant of mitochondrial targeting by aryl−ureas and can be varied to develop analogues that activate apoptosis or necrosis in a regulated fashion.  相似文献   
2.
三种卟啉类药物对DNA光敏损伤的比较   总被引:2,自引:0,他引:2  
  相似文献   
3.
从流行病学、临床症状、病理变化和实验室检验四个方面对鸡传染性喉气管炎进行了诊断,并做了药物治疗对比试验.结果表明,杀病毒药(消毒王)加清热解毒、止咳平喘中草药配合治疗鸡传染性喉气管炎,效果更好,能较快地制止病鸡死亡,显著降低死亡率及减少药物治疗费用.  相似文献   
4.
Chimeric antigen receptor (CAR) therapy is a promising modality for the treatment of advanced cancers that are otherwise incurable. During the last decade, different centers worldwide have tested the anti-CD19 CAR T cells and shown clinical benefits in the treatment of B cell tumors. However, despite these encouraging results, CAR treatment has also been found to lead to serious side effects and capricious response profiles in patients. In addition, the CD19 CAR success has been difficult to reproduce for other types of malignancy. The appearance of resistant tumor variants, the lack of antigen specificity, and the occurrence of severe adverse effects due to over-stimulation of the therapeutic cells have been identified as the major impediments. This has motivated a growing interest in developing strategies to overcome these hurdles through CAR control. Among them, the combination of small molecules and approved drugs with CAR T cells has been investigated. These have been exploited to induce a synergistic anti-cancer effect but also to control the presence of the CAR T cells or tune the therapeutic activity. In the present review, we discuss opportunistic and rational approaches involving drugs featuring anti-cancer efficacy and CAR-adjustable effect.  相似文献   
5.
Although there are many patients with brain tumors worldwide, there are numerous difficulties in overcoming brain tumors. Among brain tumors, glioblastoma, with a 5-year survival rate of 5.1%, is the most malignant. In addition to surgical operations, chemotherapy and radiotherapy are generally performed, but the patients have very limited options. Temozolomide is the most commonly prescribed drug for patients with glioblastoma. However, it is difficult to completely remove the tumor with this drug alone. Therefore, it is necessary to discuss the potential of anticancer drugs, other than temozolomide, against glioblastomas. Since the discovery of cisplatin, platinum-based drugs have become one of the leading chemotherapeutic drugs. Although many studies have reported the efficacy of platinum-based anticancer drugs against various carcinomas, studies on their effectiveness against brain tumors are insufficient. In this review, we elucidated the anticancer effects and advantages of platinum-based drugs used in brain tumors. In addition, the cases and limitations of the clinical application of platinum-based drugs are summarized. As a solution to overcome these obstacles, we emphasized the potential of a novel approach to increase the effectiveness of platinum-based drugs.  相似文献   
6.
陈元雄 《安徽化工》2005,31(1):18-21
对外消旋体药物进行分离拆分是获取手性药物的重要方法。探讨了环糊精体系包结拆分法的机理,并对运用其机理于手性药物分离中的应用作了探讨。  相似文献   
7.
色谱技术是天然产物研究中重要的分离和纯化方法。本文介绍了色谱法,并综述了其在中药标准品制备中的应用,最后对此进行了展望。  相似文献   
8.
世界天然药物市场主要集中在美国、欧洲和亚洲三大区域,全球植物药市场的年销售额已达270亿美元。在过去的10年间,以植物制剂为主体的天然药物开始走俏西方。面对“回归自然”的世界潮流,采用现代科学技术,实现中药现代化和国际化,将为人类现代医疗保健做出重大贡献。  相似文献   
9.
Organotin polyamine ethers containing acyclovir in their backbone were synthesized in moderate to high yield employing the aqueous interfacial polycondensation system. The products are high molecular weight polymers. Infrared spectroscopy of the products shows new bands characteristic of the formation of Sn–N and Sn–O bonds consistent with the proposed structure. MALDI-TOF MS below 2000 Da shows the presence of organotin and acyclovir units containing these two moieties. The products show moderate inhibition of a number of cancer cell lines and exhibit the ability to inhibit a number of viruses, particularly the herpes simplex virus-1 and varicella zoster virus that are responsible for herpes, chicken pox and shingles.  相似文献   
10.
为有效控制磁性四氧化三铁纳米粒子在水介质中的分散,防止其聚集.通过控制Na Cl溶液的物质的量浓度,对比研究磁性四氧化三铁纳米粒子在超声前和超声后在盐中的分散情况.实验结果表明,磁性四氧化三铁纳米粒子在0.4 mol/L的氯化钠中分散性最好,聚集度较小;进一步为了制备粒径均匀的复合磁性纳米载药粒子,通过调节10-羟基喜树碱溶液的p H,将10-羟基喜树碱和磁性纳米粒子制备成复合纳米粒子,并将其用二氧化硅包覆制备了复合载药纳米粒子,其复合纳米粒子的粒径大约为120 nm,结果显示通过该方法成功制备了理想的磁性纳米载药粒子.  相似文献   
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