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High-purity naringin was isolated from the fruit peels of Citrus maxima and characterized by various spectroscopic methods like UV and NMR. The isolated compound ligand (HL) was used as ligand-metal complexes synthesis after using Ag (I), Y (III) and Ru (III) metals. These ligand-metal complexes were characterized by elemental analysis, FT-IR, UV–VIS, TGA, molar conductance and magnetic properties. Cytotoxic activity of the isolated naringin and its metal complexes were investigated against two human cancer cell lines namely, white breast Adenocarcinoma (MCF7) and Lung carcinoma (A549) using cell viability assay. Transition metal increased the cytotoxic activity of naringin when they were conjugated. LC50 of Ag ligand complex demonstrated strong cytotoxicity against MCF-7 and A549 cell line that was found higher active more than three and four times the strength, respectively when compared to LC50 of Adriamycin. While LC50 of Adriamycin compound was slightly more active only about 30% and twice the strength of the Ru ligand complex against MCF-7 and A549 cell line, respectively.  相似文献   
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Background:Depression is a common psychiatric problem in the elderly and oncology patients. In elderly people with cancer, depression has a peculiar phenomenology. It has a significant impact on the quality of life. Moreover, it is associated with poor adherence to treatments, increased risk of suicide, and mortality. Nevertheless, the topic of depression in elderly people with cancer remains unexplored.Objective:The main goal of this article is to review the literature from the past 20 years on the relationships between depression, cancer, and aging.Methods:The methods followed the Prisma model for eligibility of studies. The articles in which the keywords “depression”, “cancer”, “ elderly, aging, or geriatric” were present, either in the text or in the abstract, were selected. 8.056 articles, by matching the keywords “depression and elderly and cancer,” were identified. Only 532 papers met the eligibility criteria of search limits and selection process. Out of 532 papers, 467 were considered irrelevant, leaving 65 relevant studies. Out of 65 suitable studies, 39 (60.0%) met our quality criteria and were included.Results:The risk factors associated with depression in elderly people with cancer can be divided into 4 groups: 1) tumor-related; 2) anticancer treatment-related; 3) patients-related; 4) number and type of comorbidity. The main obstacles in diagnosing depression in elderly patients with cancer are the overlap of the symptoms of cancer and side effects of treatment with the symptoms of depression but also the different ways of reporting depressive symptoms of elderly people and the different clinical types of depression. There is a lack of data regarding validated scales to assess depression in geriatric patients with cancer. Any mental illness, specifically co-occurring anxiety and depression, increases the risk of diagnosis delay and anticancer treatment adherence. Cancer and the diagnosis of mental disorders prior to cancer diagnosis correlate with an increased risk for suicide. A non-pharmacological therapeutic approach, pharmacological treatment and/or a combination of both can be used to treat elderly patients with cancer, but a detailed analysis of comorbidities and the assessment of polypharmacy is mandatory in order to avoid potential side-effects and interactions between antidepressants and the other drugs taken by the patients.Conclusion:Future research should be conducted with the aim of developing a modified and adapted assessment method for the diagnosis and treatment of depression in elderly people with cancer in order to improve their clinical outcomes and quality of life.  相似文献   
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近年来癌症治疗受到广泛关注,二氧化硅纳米颗粒因其独特的理化性质在肿瘤诊疗领域展现巨大潜力。基于二氧化硅纳米粒子的药物输送系统可被动或主动靶向肿瘤组织,并通过刺激响应的方式实现药物在肿瘤部位的可控释放,有效提高抗肿瘤药物在肿瘤部位的浓度,提高治疗效率。同时,二氧化硅纳米粒子通过负载造影剂可实现生物成像功能,用于肿瘤组织定位及药物追踪,实现更高效的抗肿瘤治疗。本文介绍了二氧化硅纳米粒子的制备方式,并对二氧化硅纳米粒子在药物靶向递送系统及生物成像领域中的研究进展进行综述。  相似文献   
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目的 制备载地高辛的聚乳酸-羟基乙酸共聚物(PLGA)纳米粒子,提高地高辛的生物利用度,降低其毒副作用.方法 建立测定地高辛-PLGA纳米粒子载药量和包封率的高效液相色谱法;采用乳化溶剂挥发法制备地高辛-PLGA纳米粒子,并通过单因素实验优化制备条件;采用噻唑蓝法评价地高辛和地高辛-PLGA纳米粒子的抗肿瘤能力.结果 以粒径为筛选条件的单因素实验结果表明,制备地高辛-PLGA纳米粒子的最佳条件为PLGA 30 mg,地高辛2 mg,二氯甲烷3 ml,聚乙烯醇质量分数0.5%,超声功率200 W.此制备条件下得到的地高辛-PLGA纳米粒子的粒径约231 nm,包封率为74.61%,载药量为5.37%,且其抗肿瘤活性优于地高辛,差异具有统计学意义(P<0.05).结论 以PLGA为载体材料制备地高辛-PLGA纳米粒子可增强地高辛的抗肿瘤作用.  相似文献   
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Receptor change induced by ligand binding is a new issue to face in the field of targeted delivery. Receptor clustering, the main pattern of receptor changes, decreases the affinity between ligand and receptor due to the redistribution of receptor position. In an attempt to respond to such challenge, we designed and constructed three RGD-modified nanocarriers with different ligand intervals: stealth liposomes modified with the monomeric RGD (moRGD-LP), dimeric RGD (diRGD-LP) and a special dimeric RGD with a linker between two cyclic RGD motifs (P-diRGD-LP). The αvβ3-positive and -negative tumor cells (Melanoma B16 and MCF-7) were used as the cell models. As a result, P-diRGD-LP demonstrated strongest interaction with B16 cells in surface plasmon resonance study and highest cellular uptake in B16 cells in real-time confocal analysis. The enhanced endocytosis of P-diRGD-LP was found to be αvβ3-mediated and P-diRGD-LP increased the involvement of the clathrin-dependent pathway. Importantly, P-diRGD-LP demonstrated the best targeting effect in B16-tumor bearing mice in both in vivo and ex vivo near-infrared fluorescent images, about 2.4-fold that of moRGD-LP and 2.8-fold that of diRGD-LP at 3 h. Further, we validated integrin αvβ3 clustering on B16 cells via a single-molecule imaging by a total internal reflection fluorescence microscopy. Finally, the 3D models of αvβ3 clustering suggested a receptor interval within 41.916–65.779 Å, while the molecular computation revealed an RGD ligand interval of 20.944 Å, 42.753 Å and 78.196 Å for diRGD-LP, P-diRGD-LP and moRGD-LP, respectively, confirming the best matching between clustered αvβ3 and P-diRGD-LP. In conclusion, P-diRGD-LP could achieve higher targeting to αvβ3-positive tumor via the enhanced interaction based on the better ligand-receptor compatibility. The design of targeted nanocarriers against receptor clustering might provide new insight into the nanotechnology-based anticancer therapy.  相似文献   
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Epidemiological and clinical studies have demonstrated that dietary supplementation of selenium (Se) could reduce the incidence of human cancers. In this study, selenocystine, a nutritionally available selenoamino acid, was identified as a novel agent with broad-spectrum antitumor activity. A panel of eight human caner cell lines was shown to be susceptible to selenocystine, with IC50 values ranging from 3.6 to 37.0 μM. Selenocystine induced dose-dependent apoptosis in A375, HepG2 and MCF7 cells was evaluated by flow cytometric analysis and annexin-V staining assay. Mechanistic studies showed time- and dose-dependent increases in intracellular reactive oxygen species (ROS) in susceptible cancer cells (MCF7 and HepG2 cells) treated with selenocystine. However, selenocystine-induced ROS overproduction was not observed in non-susceptible normal human fibroblast Hs68 cells. Significant DNA strand breaks were observed in selenocystine-treated MCF7 and HepG2 cells as examined by single-cell gel electrophoresis (Comet assay). The thiol-reducing antioxidants, glutathione and N-acetylcysteine, inhibited intracellular ROS generation, DNA strand breaks and accumulation of sub-G1 population in MCF7 cells exposed to selenocystine. Our results suggest a possible role of ROS as a mediator of the signaling pathway of selenocystine-induced, DNA damage–mediated apoptosis in susceptible cancer cells.  相似文献   
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Ethnopharmacological relevance

Inonotus obliquus (Chaga mushroom), one of the widely known medicinal mushrooms, has been used to treat various cancers in Russia and most of Baltic countries for many centuries.

Aim of the study

To examine the anti-proliferative effects of Inonotus obliquus extract on melanoma B16-F10 cells. Furthermore, to assess the anti-tumor effect of Inonotus obliquus extract in vivo in Balb/c mice.

Materials and methods

The water extract of Inonotus obliquus was studied for anti-proliferative effects on the growth and morphology of B16-F10 melanoma cells and for anti-tumor effect using in vivo in Balb/c mice.

Results

Inonotus obliquus extract not only inhibited the growth of B16-F10 cells by causing cell cycle arrest at G0/G1 phase and apoptosis, but also induced cell differentiation. These effects were associated with the down-regulation of pRb, p53 and p27 expression levels, and further showed that Inonotus obliquus extract resulted in a G0/G1 cell cycle arrest with reduction of cyclin E/D1 and Cdk 2/4 expression levels. Furthermore, the anti-tumor effect of Inonotus obliquus extract was assessed in vivo in Balb/c mice. Intraperitoneal administration of Inonotus obliquus extract significantly inhibited the growth of tumor mass in B16-F10 cells implanted mice, resulting in a 3-fold (relative to the positive control, *p < 0.05) inhibit at dose of 20 mg/kg/day for 10 days.

Conclusion

This study showed that the water extract of Inonotus obliquus mushroom exhibited a potential anticancer activity against B16-F10 melanoma cells in vitro and in vivo through the inhibition of proliferation and induction of differentiation and apoptosis of cancer cells.  相似文献   
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