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81.
金蒲抑瘤片在鼻咽癌的临床应用研究   总被引:1,自引:1,他引:1  
为探讨鼻咽癌患者放疗期间合并应用金蒲抑瘤片治疗对细胞免疫功能及血中微量元素硒、锌、铜的影响,经病理证实鼻咽癌患者58例,随机分为放疗服药组30例和单纯放疗组28例。两组放疗前后抽静脉血测定T细胞亚群(CD3+,CD4+,CD8+,CD4+/CD8+),血中微量元素硒,锌,铜并与30例健康者(正常对照组)进行比较。结果表明,鼻咽癌患者血中微量元素硒,锌,铜及CD3+,CD4+,CD4+/CD8+显著低于健康人,放疗期间合并应用金蒲抑瘤片治疗后血中微量元素硒,锌,铜及CD3+,CD4+,CD4+/CD8+较服药前显著升高。提示鼻咽癌患者细胞免疫功能低下,血中微量元素硒,锌,铜显著低于健康人。金蒲抑瘤片能提高鼻咽癌患者因中微量元素硒,锌,铜含量,使低下的细胞免疫功能迅速恢复。  相似文献   
82.
Abstract

This study focused on studying the impact of flavonoids isolated from Cleome droserifolia on HCC cell lines and to further unveil their possible impact on TP53 and its downstream tumor suppressor miRNAs. Three flavonol glycosides were isolated from C. droserifolia namely, Isorhamnetin-3-O-β-D-glucoside (1), Quercetin-3`-methoxy-3-O-(4``-acetylrhamnoside)-7-O-α-rhamnoside (2), and Kaempferol-4`-methoxy-3,7-O-dirhamnoside (3). They showed a concentration and time dependent reduction in cellular viability and anchorage-independent growth of HCC cells. Moreover, they exhibited a decrease in the migrating capacity of HepG2 cells in a pattern similar to positive control cells. (2) Showed the most potent effects in halting HCC tumorigenic activity (IC50=36?±?1.70?µM) and a repression of the cellular proliferation rate of HepG2 cells. Restoration of TP53 and its downstream tumor suppressor miRNAs; miR-15a, miR-16, miR-34a by (2) was observed. Moreover, attenuation of (2) mediated actions was shown upon using anti-miR-15a and anti-miR-16. To conclude, this study crystallizes a novel role of C. droserifolia in harnessing HCC progression in-vitro with a possible contribution of TP53/miR-15a/miR-16.  相似文献   
83.
84.
Psidium guajava L., commonly known as guava is an important tropical food plant with diverse medicinal values. In traditional medicine, it is used in the treatment of various diseases such as diarrhoea, diabetes, rheumatism, ulcers, malaria, cough, and bacterial infections. The aim of this review is to provide up-to-date information on the ethnomedicinal uses, bioactive compounds, and pharmacological activities of P. guajava with greater emphasis on its therapeutic potentials. The bioactive constituents extracted from P. guajava include phytochemicals (gallic acid, casuariin, catechin, chlorogenic acid, rutin, vanillic acid, quercetin, syringic acid, kaempferol, apigenin, cinnamic acid, luteolin, quercetin-3-O-α-L-arabinopyranoside, morin, ellagic acid, guaijaverin, pedunculoside, asiastic acid, ursolic acid, oleanolic acid, methyl gallate and epicatechin) and essential oils (limonene, trans-caryophyllene, α-humulene, γ-muurolene, selinene, caryophyllene oxide, bisabolol, isocaryophyllene, δ-cadinene, α-copaene, α-cedrene, β-eudesmol, α-pinene, β-pinene, β-myrcene, linalool, α-terpineol and eucalyptol). In vitro and in vivo studies demonstrated that P. guajava possesses pharmacological activities such as antidiabetic, antidiarrhoeal, hepatoprotective, anticancer, antioxidant, anti-inflammatory, antiestrogenic, and antibacterial activities which support its traditional uses. The exhibited pharmacological activities reported may be attributed to the numerous bioactive compounds present in different parts of P. guajava. Based on the beneficial effects of P. guajava as well as its bioactive constituents, it can be exploited in the development of pharmaceutical products and functional foods. However, there is a need for comprehensive studies in clinical trials to establish the safe doses and efficacy of P. guajava for the treatment of several diseases.  相似文献   
85.
Caffeine has been reported to induce anti-tumor immunity for attenuating breast cancer by blocking the adenosine 2A receptor. Molecular modeling showed that theacrine, a purine alkaloid structurally similar to caffeine, might be an antagonist of the adenosine 2A receptor equivalent to or more effective than caffeine. Theacrine was further demonstrated to be an effective antagonist of the adenosine 2A receptor as its concurrent supplementation significantly reduced the elevation of AMPK phosphorylation level in MCF-7 human breast cells induced by CGS21680, an agonist of adenosine 2A receptors. In an animal model, the development of mammary carcinoma induced by 7,12-Dimethylbenz[a]anthracene in Sprague–Dawley rats could be attenuated by daily supplement of theacrine of 50 or 100 mg/kg body weight. Both expression levels of cleaved-caspase-3/pro-caspase-3 and granzyme B in tumor tissues were significantly elevated when theacrine was supplemented, indicating the induction of programmed cell death in tumor cells might be involved in the attenuation of mammary carcinoma. Similar to the caffeine, significant elevation of interferon-γ and tumor necrosis factor-α was observed in the serum and tumor tissues of rats after the theacrine supplement of 50 mg/kg body weight. Taken together, theacrine is an effective antagonist of adenosine 2A receptors and possesses great potential to be used to attenuate breast cancer.  相似文献   
86.
Keyhole limpet hemocyanin (KLH): a biomedical review   总被引:10,自引:0,他引:10  
In this review we present a broad survey of fundamental scientific and medically applied studies on keyhole limpet hemocyanin (KLH). Commencing with the biochemistry of KLH, information on the biosynthesis and biological role of this copper-containing respiratory protein in the marine gastropod Megathura crenulata is provided. The established methods for the purification of the two isoforms of KLH (KLH1 and KLH2) are then covered, followed by detailed accounts of the molecular mass determination, functional unit (FU) structure, carbohydrate content, immunological analysis and recent aspects of the molecular genetics of KLH. The transmission electron microscope (TEM) has contributed significantly to the understanding of KLH structure, primarily from negatively stained images. We give a brief account of TEM studies on the native KLH oligomers, the experimental manipulation of the oligomeric states, together with immunolabelling data and studies on subunit reassociation. The field of cellular immunology has provided much relevant biomedical information on KLH and has led to the expansion of use of KLH in experimental immunology and clinically as an immunotherapeutic agent; this area is presented in some detail. The major clinical use of KLH is specifically for the treatment of bladder carcinoma, with efficacy probably due to a cross-reacting carbohydrate epitope. KLH also has considerable possibilities for the treatment of other carcinomas, in particular the epithelially derived adenocarciomas, when used as a carrier for carcinoma ganglioside and mucin-like epitopes. The widespread use of KLH as a hapten carrier and generalised vaccine component represent other major on-going aspects of KLH research, together with its use for the diagnosis of Schistosomiasis, drug assay and the treatment of drug addiction. Immune competence testing, assessment of stress and the understanding of inflammatory conditions are other areas where KLH is also making a useful contribution to medical research.  相似文献   
87.
为探讨苯乙酸(PA)对肝癌细胞系SMMC-7721的增殖抑制作用及其与RNA编辑酶ADAR1表达的相关性, 应用细胞计数及MTT法检测了不同浓度(0.5, 1.0, 2.0和4.0 mmol/L)PA对肝癌细胞系SMMC-7721的增殖抑制作用, 通过流式细胞术(FCM)分析了各细胞周期的细胞百分比, 应用半定量逆转录-聚合酶链式反应(RT-PCR)及免疫印迹杂交分析使用不同浓度(0.5, 1.0, 2.0 mmol/L)PA作用后肝癌细胞系SMMC-7721中RNA编辑酶ADAR1 mRNA及蛋白表达的变化. 结果表明, 肝癌细胞系SMMC-7721经不同浓度PA作用后, 增殖抑制率随作用时间延长及PA浓度增加而明显提高(P<0.05), 但2.0和4.0 mmol/L PA作用72 h后组间差异比较无统计学意义(P>0.05). 肝癌细胞系SMMC-7721中RNA编辑酶ADAR1 mRNA及蛋白表达随PA浓度增加而明显降低(P<0.05). 通过沉默SMMC-7721细胞中ADAR1的表达发现, ADAR1表达下调可有效抑制肝癌细胞增殖. 结果表明, PA可阻抑肝癌细胞系SMMC-7721细胞增殖, 且存在时间及剂量的依赖性, 作用机制与PA下调ADAR1表达相关.  相似文献   
88.
Pancreatic carcinoma still represents one of the most lethal malignant diseases in the world although some progress has been made in treating the disease in the past decades. Current multi-agent treatment options have improved the overall survival of patients, however, more effective treatment strategies are still needed. In this paper we have characterized the anticancer potential of coumarin-palladium(II) complex against pancreatic carcinoma cells. Cells viability, colony formation and migratory potential of pancreatic carcinoma cells were assessed in vitro, followed by evaluation of apoptosis induction and in vivo testing on zebrafish. Presented results showed remarkable reduction in pancreatic carcinoma cells growth both in vitro and in vivo, being effective at micromolar concentrations (0.5 μM). Treatments induced apoptosis, increased BAX/BCL-2 ratio and suppressed the expression of SOX9 and SOX18, genes shown to be significantly up-regulated in pancreatic ductal adenocarcinoma. Importantly, treatments of the zebrafish-pancreatic adenocarcinoma xenografts resulted in significant reduction in tumor mass, without provoking any adverse toxic effects including hepatotoxicity. Presented results indicate the great potential of the tested compound and the perspective of its further development towards pancreatic cancer therapy.  相似文献   
89.
Hepatocellular carcinoma (HCC) is a highly malignant tumor related to high mortality and is still lacking a satisfactory cure. Tumor metastasis is currently a major challenge of cancer treatment, which is highly related to angiogenesis. The vascular endothelial growth factor (VEGF)/VEGFR signaling pathway is thus becoming an attractive therapeutic target. Moreover, chemotherapy combined with gene therapy shows great synergistic potential in cancer treatment with the promise of nanomaterials. In this work, a formulation containing 5-FU and siRNA against the VEGF/VEGFR signaling pathway into N-acetyl-galactosamine (GalNAc)-modified nanocarriers is established. The targeting ability, biocompatibility and pH-responsive degradation capacity ensure the efficient transport of therapeutics by the formulation of 5-FU/siRNA@GalNAc-pDMA to HCC cells. The nano-construct integrated with gene/chemotherapy exhibits significant anti-metastatic HCC activity against C5WN1 liver cancer cells with tumorigenicity and pulmonary metastasis in the C5WN1-induced tumor-bearing mouse model with a tumor inhibition rate of 96%, which is promising for future metastatic HCC treatment.  相似文献   
90.
A drug (5-FU) was employed to treat the gastric carcinoma cells and induce apoptosis of the cancer cells. Raman spectra obtained from single gastric carcinoma cells and the induced apoptotic cells through scan-excitation mode were used to analyze the effectiveness of the treatment. The major difference of the apoptotic cells from the cancer cells are the reduction in intensities of vibration bands generated by cellular lipids, proteins and nucleic acids. In particular, large intensity reduction in nucleic vibrations at 782, 1092, 1320, 1340, and 1578 cm−1 was observed upon apoptosis of the gastric carcinoma cells. Up to 45% reduction in the magnitude of the 782 cm−1 peak in Raman spectra of the apoptotic cells was observed, which suggests the breakdown of phosphodiester bonds and DNA bases. We showed that the principal components analysis (PCA), a multivariate statistical tool, can be used to distinguish single apoptotic cells and gastric carcinoma cells based on their Raman spectra.  相似文献   
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