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Zhang X.-F.,Nanjing University | Zhu Y.,Nanjing Medical University | Zhu Y.,Chinese Institute of Clinical Medicine | Liang W.-B.,Jiangsu Province Blood Center | And 2 more authors.
Endocrine | Year: 2014

Increased cyclooxygenase-2 (COX-2) expression is associated with pancreatic β-cell dysfunction. We previously demonstrated that the transcription factor Ets-1 significantly up-regulated COX-2 gene promoter activity. In this report, we used the pancreatic β-cell line INS-1 and isolated rat islets to investigate whether Ets-1 could induce β-cell dysfunction through up-regulating COX-2 gene expression. We investigated the effects of ETS-1 overexpression and the effects of ETS-1 RNA interference on endogenous COX-2 expression in INS-1 cells. We used site-directed mutagenesis and a dual luciferase reporter assay to study putative Ets-1 binding sites in the COX-2 promoter. The effect of ETS-1 1 overexpression on the insulin secretion function of INS-1 cells and rat islets and the potential reversal of these effects by a COX-2 inhibitor were determined in a glucose-stimulated insulin secretion (GSIS) assay. ETS-1 overexpression significantly induces endogenous COX-2 expression, but ETS-1 RNA interference has no effect on basal COX-2 expression in INS-1 cells. Ets-1 protein significantly increases COX-2 promoter activity through the binding site located in the -195/-186 region of the COX-2 promoter. ETS-1 overexpression significantly inhibited the GSIS function of INS-1 cells and islet cells and COX-2 inhibitor treatment partly reversed this effect. These findings indicated that ETS-1 overexpression induces β-cell dysfunction partly through up-regulation of COX-2 gene expression. Moreover, Ets-1, the transcriptional regulator of COX-2 expression, may be a potential target for the prevention of β-cell dysfunction mediated by COX-2. © 2013 Springer Science+Business Media. Source

Ma L.,Jiangsu Province Blood Center
Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology | Year: 2011

The purpose of this study was to investigate the distribution of 10 rare red blood groups in Chinese Nanjing population, so as to provide compatible rare blood to patients and to create a donor data bank. Jk (a-b-) (Kidd) phenotypes were detected by urea, while H-(H), GPA-(MNS), GPC-(Gerbich), i+ (Ii) and Lub-(Lutheran) phenotypes were detected by monoclonal, polyclonal antibodies with U type 96 well microplate technology. The screening of Jsb- and k-(Kell), Fya-(Duffy), Ok-(Ok), s-(MNS) and Dib-(Digeo) phenotypes were performed by polymerase chain reaction. The results showed that 2 Jk (a-b-) out of 40337 donation samples and 3 Fy (a-b+) out of 1782 donation samples were found, while no other rare blood phenotypes (H-, GPA-, GPC-, Lub-, Ok-, s-, Jsb-, k-, Dib- and i+) were detected. It is concluded that the frequencies of Jk (a-b-) and Fya(a-b+) are 0.0049% and 0.168% respectively. No more rare blood phenotype was found in this screening. Source

Peng Y.-P.,Nanjing Medical University | Zhang J.-J.,Nanjing Medical University | Liang W.,Jiangsu Province Blood Center | Tu M.,Nanjing Medical University | And 8 more authors.
BMC Cancer | Year: 2015

Background: Natural killer (NK) cells play a key role in non-specific immune response in different cancers, including pancreatic cancer. However the anti-tumor effect of NK cells decreases during pancreatic cancer progression. The regulatory pathways by which NK cells facilitate tumor immune escape are unclear, therefore our purpose was to investigate the roles of the contributory factors. Methods: NK cells isolated from fresh healthy peripheral blood were co-cultured with normal human pancreatic ductal cells hTERT-HPNE and human pancreatic cancer cell lines SW1990 and BxPc-3 in vitro. Then NK cell function was determined by Flow cytometric analysis of surface receptors and cytotoxic granules in NK cells, NK cell apoptosis and cytotoxicity, and Enzyme-linked immunosorbent assay of cytokines. Expression level of MMP-9, IDO and COX-2 in hTERT-HPNE and SW1990 cells were detected by quantitative RT-PCR. Statistical differences between data groups were determined by independent t-tests using SPSS 19.0 software. Results: Our results showed that NK cell function was significantly downregulated following exposure to pancreatic cancer cells compared to normal pancreatic cells, as demonstrated by lower expressions of activating surface receptors (NKG2D, DNAM-1, NKp30 and NKp46) and cytotoxic granules (Perforin and Granzyme B); decreased secretion of cytokines (TNF-α and IFN-γ); and reduced cytotoxicity against myelogenous leukemia K562 cells. Further investigations revealed that MMP-9 and IDO may be implicated in SW1990 cell-induced NK cell dysfunction by facilitating tumor immune evasion. Blockade by TIMP-1 and/or 1-MT could partially restore NK function. Conclusions: Taken together, elevation of MMP-9 and IDO induced by pancreatic cancer cells mediates NK cell dysfunction. Our findings could contribute to the development of NK cell-based immunotherapy in patients with pancreatic cancer. © 2014 Peng et al.; licensee BioMed Central Ltd. Source

Ma L.,Jiangsu Province Blood Center
Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology | Year: 2013

The aim of this study was to investigate the feasibility of using RASSF1A gene as a universal fetal marker in maternal plasma. Two methods of circulating cell-free fetal DNA (cffDNA) extracted from maternal plasma were compared. The better one was chosen for extraction of cffDNA in the 20 pregnant samples. The SRY gene and the RASSF1A gene treated with methylation-sensitive restriction enzyme were amplificated by RT-PCR and the PCR system was optimized. The results showed that the SRY gene was found in 11 out of the 20 pregnant samples, which was consistent with the postnatal sex. Using the optimized PCR system, the specifically amplified fetal-associated methylated RASSF1A gene was found after treatment with BstUI in 18 of the 20 pregnant samples, while the 2 samples failed in detection. It is concluded that the methylated fetal-specific RASSF1A gene can be used as a universal fetal marker for the presence of cffDNA in maternal plasma without fetal gender restrictions. So, it can be used for noninvasive prenatal diagnosis. Source

Li Z.,Nanjing Southeast University | Li Z.,Nanjing University of Posts and Telecommunications | Li Z.,Nanjing Longliang Biological Science and Technology Ltd Company | Yang H.,Nanjing Southeast University | And 10 more authors.
Journal of Biomedical Nanotechnology | Year: 2013

For reducing the steric hindrance and nonspecific binding of the target DNA, the dextran was used as molecular arms to be immobilized on the surface of magnetic nanoparticles (MNPs). Magnetic separation was used in preparation of dextran- MNPs (DMNPs). Aspartic acid and aminated DNA probe were successively modified on the dextran immobilized on the surface of MNPs. These probe-DMNPs were successfully applied to detect biotin-labeled PCR product of E. coli O157:H7 genome by hybridization. Then the complexes were bonded with streptavidin-modified alkaline phosphatase (ALP-SA). Finally the chemiluminescent signals were detected by adding 3-(2-spiroadamantane)-4- methoxy-4- (3-phosphoryloxy) phenyl-1,2-dioxetane (AMPPD). The results showed that this method had a good specificity, and higher sensitivity than that when only MNPs were used as solid carriers. Copyright © 2013 American Scientific Publishers All rights reserved. Source

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