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991.
Yu Dahai Sun Sanyuan Lu Hong Zhao Di Zhou Chong 《Cell biochemistry and biophysics》2013,67(1):175-180
Esophageal carcinoma (EC) is an aggressive and the third most common cancer of the digestive tract with poor prognosis. Replication protein A (RPA) is critically required for DNA replication and its elevated expression has been observed in many malignant tumors. In this study, we investigated the expression of RPA1 and RPA2, subunits of RPA, and assessed their prognostic value in EC patients. We analyzed immunohistochemically the expression of RPA1 and RPA2 proteins in 48 EC resection specimens in relation with clinicopathological parameters and survival. We observed a significant elevated (P < 0.001) RPA1 and RPA2 expressions (labeling index) in the tumor than adjacent non-tumor tissues. In addition, both RPA1 and RPA2 labeling index in lymph node metastasis patients was significantly higher (both P = 0.000) than patients without lymph node metastasis. However, RPA1 and RPA2 labeling index in early stage was significantly lower (P = 0.000 and P = 0.002, respectively) than that of late stage EC patients. Importantly, patient’s survival at early stage was significantly higher (P = 0.016) than late stage EC and lymph node metastasis and RPA1 expression was associated with adverse patient’s outcome in multivariate analysis (P < 0.05 and P < 0.00, respectively). In conclusion, RPA1 could be a useful prognostic indicator in patients with esophageal carcinoma and might be a future attractive therapeutic target for regulation by tumor suppressors. 相似文献
992.
Peijing Li Yunhua Gao Zheng Liu Kaibin Tan Zhongxiong Zuo Hongmei Xia Dan Yang Yi Zhang Debin Lu 《Cell biochemistry and biophysics》2013,66(3):775-786
Non-viral vector transfection efficiency is an issue affecting the clinical application of stem cell gene therapy. This study makes use of the synergistic effect of combining ultrasound (US) with microbubbles (MB) and polyethylenimine (PEI) to increase DNA transfection efficiency, which will enhance the efficiency of gene transfer to bone marrow stromal cells (BMSCs). The optimal parameters for primary-cultured rat-BMSC DNA transfection were examined. The study was arranged based on uniform design. Using a construct containing hepatocyte growth factor (HGF) tagged with enhanced green fluorescent protein (pEGFP-HGF) as example, the mixture of BMSCs, MB, and PEI:DNA complex were exposed to US with frequency of 1 MHz and 10 % duty cycle pulses. Other factors such as acoustic intensity (Q), MB dosage, and total treatment time (T) were also tested. The results were analyzed by regression analysis. Using the best match of parameters, Q = 0.6 W/cm2, MB = 106/ml, T = 30 s, different groups were compared. The cooperativity of MB-mediated US and PEI enhanced the gene transfection efficiency by nearly 38-times compared to the DNA without US group. Furthermore, the expression of HGF protein was confirmed by Western blot. The eGFP could be not only seen mainly at the cytoplasm, but also seen in the nucleus in a small proportion of the cells (<10 %) for up to 7 observed days. The transfected BMSCs maintained their capability of multi-directional differentiation and reproductive activity. Our results provide useful information in establishing a novel non-viral transfection method, which may be applied to clinical application in stem cell gene therapy. 相似文献
993.
Feng Qiu Chun‐hua Shi Jun Zheng Yu‐bin Liu 《Journal of biochemical and molecular toxicology》2013,27(7):364-369
This study was conducted to investigate the biological role of periostin in gastric cancer (GC) under hypoxia. Western blot analysis revealed that along with an upregulation of hypoxia‐inducible factor‐1alpha, there was a time‐dependent induction of periostin in MKN‐45 cells under hypoxia (2% O2), increasing by eightfold as compared to normoxic cells. Pretreatment with 30 µM PD98059, an inhibitor of ERK1/2, significantly reduced hypoxia‐stimulated periostin expression (P < 0.01). Periostin knockdown in MKN‐45 cells was achieved by specific small interfering RNA (siRNA). The conditioned medium from periostin siRNA‐transfected MKN‐45 cells induced significantly less (P < 0.01) endothelial tube formation than control siRNA‐transfected cells. Additionally, periostin silencing markedly decreased the mRNA expression and secretion of vascular endothelial growth factor (VEGF) in hypoxic MKN‐45 cells. Thus, our data suggest that periostin is a hypoxia‐response gene and mediates a cross talk between GC and endothelial cells under hypoxia, partially through regulation of the VEGF expression. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:364‐369, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21498 相似文献
994.
The primary culture of mirror carp snout and caudal fin tissues and the isolation of Koi herpesvirus
Jingxiang Zhou Hao Wang Xia Zhu Xingwei Li Wenliang Lv Dongming Zhang 《In vitro cellular & developmental biology. Animal》2013,49(9):734-742
The explosive Koi herpesvirus (KHV) epidemic has caused the deaths of a large number of carp and carp variants and has produced serious economic losses. The mirror carp (Cyprinus carpio var. specularis) exhibits strong environmental adaptability and its primary cells can be used to isolate KHV. This study utilized the tissue explant method to systematically investigate primary cell culture conditions for mirror carp snout and caudal fin tissues. We demonstrated that cells from these two tissue types had strong adaptability, and when cultured in Medium 199 (M199) containing 20% serum at 26 to 30°C, the cells from the snout and caudal fin tissues exhibited the fastest egress and proliferation. Inoculation of these two cell types with KHV-infected fish kidney tissues produced typical cytopathic effects; additionally, identification by electron microscopy, and PCR indicated that KHV could be isolated from both cell types. 相似文献
995.
996.
997.
Min Wang Heng Jiang Zhiguo Song Hong Gong 《Preparative biochemistry & biotechnology》2013,43(4):372-379
Abstract An efficient synthesis of 3,4-dihydropyrimidin-2(1H)-ones from aldehydes, 1,3-dicarbonyl compounds, and urea using copper nitrate under refluxing temperature in ethanol was described. Compared with other Lewis copper salts, copper nitrate proved to be the most efficient. The advantages of the new method were good yields (61–93%), short reaction time (0.4–3 h), and inexpensive catalyst. 相似文献
998.
A cane molasses-based medium for the biomass production of biocontrol agent Rhodosporidium paludigenum was statistically optimized. Molasses concentration (after pretreatment), yeast extract, and initial pH were identified by the Plackett–Burman design to show significant influence on the biomass production. The three factors were further optimized by central composite design and response-surface methodology. The statistical analysis indicated the optimum values of the variables were 89.98 g/L for cane molasses, 2.35 g/L for yeast extract and an initial pH of 8.48. The biomass yield at the optimal culture achieved 15.89 g/L in flask fermentation, which was 2.1 times higher than that at the initial NYDB medium. In a 10-L fermenter, 18.97 g/L of biomass was obtained after 36 hr of cultivation. Moreover, the biocontrol efficacy of the yeast was investigated after culture optimization. The results showed the yeast harvested in the optimal medium maintained its initial biocontrol properties by reducing the percentage of decayed apples to below 20%. 相似文献
999.
1000.