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1.

Purpose

To investigate the prognostic value of intratumoral invariant natural killer T (iNKT) cells and interferon-gamma (IFN-γ) in hepatocellular carcinoma (HCC) after curative resection.

Experimental Design

Expression of TRAV10, encoding the Vα24 domain of iNKT cells, and IFN-γ mRNA were assessed by quantitative real-time polymerase chain reaction in tumor from 224 HCC patients undergoing curative resection. The prognostic value of these two and other clinicopathologic factors was evaluated.

Results

Either intratumoral iNKT cells and IFN-γ alone or their combination was an independent prognostic factor for OS (P = 0.001) and RFS (P = 0.001) by multivariate Cox proportional hazards analysis. Patients with concurrent low levels of iNKT cells and IFN-γ had a hazard ratio (HR) of 2.784 for OS and 2.673 for RFS. The areas under the curve of iNKT cells, IFN-γand their combination were 0.618 vs 0.608 vs 0.654 for death and 0.591 vs 0.604 vs 0.633 for recurrence respectively by receiver operating characteristic curve analysis. The prognosis was the worst for HCC patients with concurrent low levels of iNKT cells and IFN-γ, which might be related with more advanced pTNM stage and more vascular invasion.

Conclusions

Combination of intratumoral iNKT cells and IFN-γ is a promising independent predictor for recurrence and survival in HCC, which has a better power to predict HCC patients’ outcome compared with intratumoral iNKT cells or IFN-γ alone.  相似文献   
2.
【目的】研究蚯蚓提取物对家蚕Bombyx mori中肠组织氧化应激及抗氧化酶含量的影响,探究蚯蚓提取物的抗氧化功能。【方法】分别给家蚕5龄幼虫饲喂蚯蚓(赤子爱胜蚓Eisenia foetida)提取液原液的50, 100和200倍稀释液处理后的桑叶,测定处理6 d后家蚕中肠组织中氧化损伤产物丙二醛(MDA)和乳酸脱氢酶(LDH)的含量;利用qRT-PCR检测家蚕中肠组织中抗氧化酶关键基因(Cat,Sod和GSH-Px)的mRNA表达水平;同时采用ELISA法检测中肠组织中抗氧化酶[过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)]含量及总抗氧化能力(T-AOC)。【结果】与对照组相比,50, 100和200倍稀释组家蚕中肠组织中MDA, CAT, SOD和GSH-Px含量及T-AOC均差异不显著,200倍稀释组LDH含量显著降低了9.85%,100倍稀释组中肠中Cat和GSH-Px的表达量均显著高于对照组,3个稀释组中Sod的表达量均显著高于对照组。【结论】添食蚯蚓提取物可通过降低家蚕中肠LDH含量、提高抗氧化酶基因的表达水平进而提高家蚕的抗氧化能力。  相似文献   
3.
Deregulation of ceramide metabolism is a hallmark of human cancer. Ceramide analogues thereby represent a new class of anti-cancer agents. We aimed at developing effective and low toxic ceramide analogues and synthesized a new class of ceramide analogues starting from l-threonine. Several analogues exhibit potent cytotoxicity against human cancer cells in vitro with IC50 as low as 4.8?μM. These ceramide analogues decreased xIAP and Bcl-xL level and exhibited significant sensitization activity to overcome human cancer cell resistance to TRAIL, a cancer-selective agent that are being tested in human clinical trials. Furthermore, we determined that these ceramide analogues effectively suppress human cancer xenograft growth in vivo with no significant toxicity at the efficacious dose. Therefore, we have developed a simple and effective method to synthesize functional ceramide analogues using l-threonine as starting material and these analogues have the great potential to be further developed as anti-cancer agents in human cancer therapy.  相似文献   
4.
Ovarian cancer characterizes as the fourth leading consequence of death associated with cancer for women. Accumulating evidence underscores the vital roles of microRNAs (miRNAs) in preventing ovarian cancer development. Besides, induction of the phosphatidylinositol-3 kinase/serine/threonine kinase (PI3K/Akt) pathway associated with the ovarian cancer cell migration and invasion. The study aims to examine the effects of miR-15b on the proliferation, apoptosis, and senescence of human ovarian cancer cells by binding to lysophosphatidic acid receptor 3 (LPAR3) with the involvement of the PI3K/Akt pathway. The positive expression of LPAR3 protein was detected by immunohistochemistry. Then the interaction between miR-15b and LPAR3 was examined. The possible role of miR-15b in ovarian cancer was explored using gain- and loss-of-function experiments. Subsequently, the functions of miR-15b on PI3K/Akt pathway, proliferation, migration, invasion, senescence and apoptosis of ovarian cancer cells were assessed. Furthermore, in vivo tumorigenicity assay in nude mice was performed. LPAR3 was overexpressed, whereas miR-15b was poorly expressed in ovarian cancer tissues. LPAR3 is a direct target of miR-15b. Restored miR-15b promoted Bax expression, apoptosis, and senescence, inhibited expression of LPAR3 and Bcl-2, the extent of PI3K and Akt phosphorylation, as well as ovarian cancer cell proliferation, migration, and invasion. Further, tumor growth was observed to be prevented by miR-15b overexpression. Collectively, our study demonstrates that miR-15b represses the proliferation and drives the senescence and apoptosis of ovarian cancer cells through the suppression of LPAR3 and the PI3K/Akt pathway, highlighting an antitumorigenic role of miR-15b.  相似文献   
5.
斯氏黄河猴(哺乳动物纲,灵长目)较完整下颌骨的发现   总被引:1,自引:1,他引:0  
新发现的下颌骨说明斯氏黄河猴下齿式为 2?, 1,3, 3。 p2为双根齿,其前后有短的齿隙;p3具有低小的后跟;p4未臼齿化,无下前尖,有初始的下后尖,在较大的跟盆上,有明显的下次尖和很小的下内尖?; m1下前尖小,有些前后收缩(与Rencunius zhowi比较),m3下次小尖不如正模发育。下颌骨联合部倾斜,不愈合。黄河猴的下臼齿在形态上与西瓦兔猴亚科和原始类人猿──渐新猿亚科有许多共同点,但上臼齿形态差异显著。黄河猴类可能出自亚洲的cercamoniine形的兔猴形灵长类。  相似文献   
6.
布鲁菌病是系统性感染性疾病,临床表现多样,在非流行区易被忽视。本病以骨关节受累常见,关节症状多数为反应性关节炎,以单关节化脓性关节炎为首发表现的病例少见。本文报道1例布鲁杆菌性化脓性单膝关节炎的临床表现和诊疗情况。  相似文献   
7.
Apoptosis proteins have a central role in the development and the homeostasis of an organism. These proteins are very important for understanding the mechanism of programmed cell death. The function of an apoptosis protein is closely related to its subcellular location. It is crucial to develop powerful tools to predict apoptosis protein locations for rapidly increasing gap between the number of known structural proteins and the number of known sequences in protein databank. In this study, amino acids pair compositions with different spaces are used to construct feature sets for representing sample of protein feature selection approach based on binary particle swarm optimization, which is applied to extract effective feature. Ensemble classifier is used as prediction engine, of which the basic classifier is the fuzzy K-nearest neighbor. Each basic classifier is trained with different feature sets. Two datasets often used in prior works are selected to validate the performance of proposed approach. The results obtained by jackknife test are quite encouraging, indicating that the proposed method might become a potentially useful tool for subcellular location of apoptosis protein, or at least can play a complimentary role to the existing methods in the relevant areas. The supplement information and software written in Matlab are available by contacting the corresponding author.  相似文献   
8.
目的:探讨地高辛抗血清对大鼠实验性心肌缺血/再灌注损伤(MI/R)的心肌氧化应激的影响。方法:采用左冠状动脉前降支结扎30min,复灌45min建立在体大鼠MI/R模型。SD大鼠随机分成假手术组、缺血/再灌注模型组、生理盐水组、维拉帕米组、小、中、大剂量地高辛抗血清组:于再灌注45min后检测左室心尖部缺血区心肌中内洋地黄素含量、心肌细胞膜Na^+,K^+-ATP酶和SOD活性以及MDA含量,光镜下观察心肌组织形态学变化。结果:MI/R组和生理盐水组大鼠心肌组织内洋地黄素水平明显升高,细胞膜Na^+,K^+-ATP酶活性明显下降,心肌组织SOD活性降低,MDA水平升高。治疗组包括维拉帕米组均能减轻心肌组织结构损伤,降低MDA水平,部分恢复SOD活性;但只有地高辛抗血清能降低心肌组织内洋地黄素水平,恢复心肌细胞膜Na^+,K^+-ATP酶活性。结论:地高辛抗血清通过拮抗内洋地黄素,恢复心肌细胞膜Na^+,K^+-ATP酶活性,从而减轻缺血/再灌注时的氧自由基损伤。  相似文献   
9.
It is a critical challenge to develop automated methods for fast and accurately determining the structures of proteins because of the increasingly widening gap between the number of sequence-known proteins and that of structure-known proteins in the post-genomic age. The knowledge of protein structural class can provide useful information towards the determination of protein structure. Thus, it is highly desirable to develop computational methods for identifying the structural classes of newly found proteins based on their primary sequence. In this study, according to the concept of Chou's pseudo amino acid composition (PseAA), eight PseAA vectors are used to represent protein samples. Each of the PseAA vectors is a 40-D (dimensional) vector, which is constructed by the conventional amino acid composition (AA) and a series of sequence-order correlation factors as original introduced by Chou. The difference among the eight PseAA representations is that different physicochemical properties are used to incorporate the sequence-order effects for the protein samples. Based on such a framework, a dual-layer fuzzy support vector machine (FSVM) network is proposed to predict protein structural classes. In the first layer of the FSVM network, eight FSVM classifiers trained by different PseAA vectors are established. The 2nd layer FSVM classifier is applied to reclassify the outputs of the first layer. The results thus obtained are quite promising, indicating that the new method may become a useful tool for predicting not only the structural classification of proteins but also their other attributes.  相似文献   
10.
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