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991.
Renal cell carcinoma (RCC) has been shown to be susceptible to immunotherapeutic treatment strategies. In the present study, patient-derived tumor cells were fused with allogeneic dendritic cells (DC) to elicit anti-tumor activity against RCC. DC from HLA-A2+ healthy donors were fused with primary RCC cells from ten patients. Phenotype of fusion cells were characterized by flow cytometer and confocal microscopy. In vitro, T cell proliferation, IFN-γ secretion and cytotocic T lymphocytes (CTL) activity elicited by allogeneic DC/RCC fusion cells were assessed. Clinically, ten patients were vaccinated with allogeneic DC/RCC fusion vaccine. The adverse effects and toxicity were observed. The clinical response was evaluated by CT scans. After fusion, the created hybrids expressed both tumor associated antigen and DC-derived molecules and could stimulate the proliferation and IFN-γ secretion of T cells as well as elicit strong CTL activity against RCC cells in vitro. In vivo, no serious adverse effects, toxicity, or signs of autoimmune disease were observed after vaccination therapy. Percentage of T lymphocyte subsets in peripheral blood of patients was increased significantly. One of ten patients exhibited a partial response with regression of lung metastases. Six patients showed stable disease with stabilization of previously progressive disease (follow up 1.5 years). The PR and SD responses, exhibited by 7/10 patients who received the allogeneic DC/RCC fusion vaccine treatment, suggest that this approach is safe and can elicit immunological responses in a significant portion of patients with RCC. J. Zhou and D. Weng contributed equally.  相似文献   
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鸡冠花种子营养成分的研究   总被引:7,自引:0,他引:7  
鸡冠花种子可供食用和药用。作者采用常规方法系统地分析测定了其营养成分,并和一些谷类,豆类食物进行了比较。结果显示,鸡冠花种子含各种营养成分:蛋白质、脂肪、碳水化合物、膳食纤维、氨基酸、维生素、无机元素等,不仅含量丰富且高于谷类。这为开发利用鸡冠花种子提供了科学依据。  相似文献   
995.
用免疫细胞化学LSAB法,兔抗人孕酮受体抗体(适用于小鼠)显示小鼠卵巢、输卵管、子宫和阴道中的孕酮受体。结果显示:未注射RU486的动物的子宫与阴道内孕酮受体丰富,输卵管中含量较少,卵巢中未见阳性反应物质。RU486注射4天后,子宫与阴道中孕酮受体明显减少;注射后7天,输卵管、子宫和阴道都为阴性反应。该结果显示了孕酮受体在雌性小鼠生殖系统内的分布特点,提示RU486封闭孕酮受体的最佳时间为用药后第7天。  相似文献   
996.

Objective

Adenylyl cyclases (ACs) play important role in regulating pancreatic beta cell growth, survival and secretion through the synthesis of cyclic AMP (cAMP). MDL-12,330A and SQ 22536 are two AC inhibitors used widely to establish the role of ACs. The goal of this study was to examine the effects of MDL-12,330A and SQ 22536 on insulin secretion and underlying mechanisms.

Methods

Patch-clamp recording, Ca2+ fluorescence imaging and radioimmunoassay were used to measure outward K+ currents, action potentials (APs), intracellular Ca2+ ([Ca2+]i) and insulin secretion from rat pancreatic beta cells.

Results

MDL-12,330A (10 µmol/l) potentiated insulin secretion to 1.7 times of control in the presence of 8.3 mmol/l glucose, while SQ 22536 did not show significant effect on insulin secretion. MDL-12,330A prolonged AP durations (APDs) by inhibiting voltage-dependent K+ (KV) channels, leading to an increase in [Ca2+]i levels. It appeared that these effects induced by MDL-12,330A did not result from AC inhibition, since SQ 22536 did not show such effects. Furthermore, inhibition of the downstream effectors of AC/cAMP signaling by PKA inhibitor H89 and Epac inhibitor ESI-09, did not affect KV channels and insulin secretion.

Conclusion

The putative AC inhibitor MDL-12,330A enhances [Ca2+]i and insulin secretion via inhibition of KV channels rather than AC antagonism in beta cells, suggesting that the non-specific effects is needed to be considered for the right interpretation of the experimental results using this agent in the analyses of the role of AC in cell function.  相似文献   
997.
It has been hypothesized that xylanase inhibitors play important roles in plant defense against microbial pathogens. Currently, there is little information available about xylanase inhibitor OsXIP in rice and its gene expression. We cloned a xylanase inhibitor gene OsXIP from rice (Oryza sativa L. cv. Nipponbare) genomic DNA. To determine the function of OsXIP, we generated OsXIP-overexpressing transgenic rice plants. The transgenic plants had significantly higher OsXIP expression and showed enhanced defense response to Magnaporthe oryzae compared to the wild-type plants. The results also showed that the increased OsXIP expression was accompanied by the up-regulation of pathogenesisrelated genes. To clarify the OsXIP expression pattern, a ProOsXIP::GUS vector was constructed and transgenic plants were obtained. GUS staining results revealed that OsXIP showed organ-specific expressions in rice plants. OsXIP was primarily expressed in the roots and in the veins, but it was weakly expressed in the leaves. Analyses of the OsXIP expression in response to biotic and abiotic stresses indicated that it was drastically induced by biotic stresses and methyl jasmonate treatment. OsXIP, a member of a new class of antifungal proteins, may function as a barrier that prevents the cell wall degradation by xylanases excreted by fungal pathogens. The OsXIP was found to be a stressresponsive gene and it could take part in plant defense via a JA-mediated signaling pathway.  相似文献   
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Hepatocellular carcinoma is one of the most common malignancies and has a poor prognosis. The ubiquitin-proteasome pathway is required for the degradation of most short-lived proteins. CMTM6 has been implicated in the progression of various tumors, but its biological function and the underlying molecular mechanisms in HCC are still unknown. In this study, we found that the expression of CMTM6 was significantly reduced in HCC and predicted better prognosis of HCC patients. Through in vitro and in vivo experiments, CMTM6 was shown to inhibit the proliferation of HCC cells by blocking the G1/S phase transition. Mechanistically, CMTM6 interacted with p21 and prevented its ubiquitination mediated by SCFSKP2, CRL4CDT2 and APC/CCDC20 in a cell-cycle–independent manner. As a result, CMTM6 stabilized p21 protein, leading to the inactivation of pRB/E2F pathway. Additionally, CMTM6 sensitized HCC cells to doxorubicin and cisplatin, positively correlated with better clinical outcomes of the transarterial chemoembolization (TACE) treatment for postoperative recurrence. Taken together, our study reports a novel mechanism by which p21 can be stabilized by CMTM6 and pinpoints a crucial role of the CMTM6-p21 axis in suppressing the progression of HCC and sensitizing patients with postoperative recurrence to TACE treatment.Subject terms: Cancer therapeutic resistance, Tumour biomarkers, Liver cancer  相似文献   
1000.
In the past decades,many materials have been studied as carriers for targeted drug delivery.However,there is a need for utilizable and selective carrier materia...  相似文献   
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