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Pem gene is one of the homeobox gene. Unlike members of Hox gene family, Pem gene is unique located at the proximal end of the X chromosome and its expression has been detected in several immortalized and transformed cells, placenta, embryos and reproductive tissues. Numeral studies showed that its expression is controlled by hormone such as androgen. This review discussed the possible role of Pem in regulating genes involved in the differentiation and development of extraembryonic tissue, spermatogenesis and sperm maturation.  相似文献   
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AIM: To identify the gene expression profiles of CNE1 cells stably transfected with NP9 expressing plasmid, and to explore the potential molecular function of NP9 gene.METHODS: CNE1 cells stably expressing NP9 protein and CNE1 cells transfected with empty vector were used as test and control. Differentially expressed genes were screened with high- throughout human genome array. Differential expression of 6 genes was analyzed with quantitative RT-PCR. RESULTS: Of all the 14 500 human genes in array, 266 genes were revealed differential expression between test and control , of which 82 genes (RA>1)were up-regulated in test and 184 genes (RA<1) were down-regulated. 34 genes and 75 genes were found distinctively up-regulation (RA>1.5) and down-regulation (RA<1.5),respectively.CONCLUSION: NP9 expression in CNE1 cells leads to changes of some genes involved in regulation of cell cycle, cell proliferation and differentiation, cell signal transduction, cell adhesion. Some new clues may be provided for further studying the potential function and molecular mechanism of NP9 gene.  相似文献   
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AIM: To investigate the effects of NF-κB decoy oligodeoxynucleotides (ODNs) on apoptosis in lung cancer cell A549. METHODS: The treatments of lung cancer cells (A549) were divided into three groups: group A (control group); group B (decoy ODN group) and group C (scramble decoy ODN group). FITC-labeled NF-κB decoy ODNs was transfected into A549 with LipofectAMINETM2000. The activation was observed by electrophoretic mobility shift assays (EMSA). The proliferation was observed by growth curve. The apoptosis of cells were observed by flow cytometry and TdT mediated dUTP-biotin Nick End Labeling (TUNEL). The expression of Bcl-2 and Fas were observed by Western blot. RESULTS: After FITC-labeled decoy ODNs was transfected for 1 hour, the decoy ODNs was detected in the nuclei of A549 cells. EMSA performed the depression of the NF-κB binding to the nucleus. The growth curve showed the inhibition of the A549 cell growth and the percentage of apoptosis was increased compare with control group by flow cytometry and TUNEL. The amount of apoptosis inhibitor (Bcl-2) in group A and group C were 2.0 times and 2.1 times more than that in group B, respectively. The level of apoptosis accelerator (Fas) in group B were 2.6 times and 2.3 times more than that in group A and group C, respectively via Western blot. CONCLUSION: The NF-κB decoy ODNs accelerate the apoptosis of lung cancer cell A549 and the mechanism may be due to its inhibiting the expression of Bcl-2 and increasing the level of Fas.  相似文献   
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There is a dialogue between the developing conceptus (embryo-fetus and associated placental membranes) and maternal uterus which must be established during the peri-implantation period for pregnancy recognition signaling, implantation, regulation of gene expression by uterine epithelial and stromal cells, placentation and exchange of nutrients and gases. The uterus provide a microenvironment in which molecules secreted by uterine epithelia or transported into the uterine lumen represent histotroph required for growth and development of the conceptus and receptivity of the uterus to implantation. Pregnancy recognition signaling mechanisms sustain the functional lifespan of the corpora lutea (CL) which produce progesterone, the hormone of pregnancy essential for uterine functions that support implantation and placentation required for a successful outcome of pregnancy. It is within the peri-implantation period that most embryonic deaths occur due to deficiencies attributed to uterine functions or failure of the conceptus to develop appropriately, signal pregnancy recognition and/or undergo implantation and placentation. With proper placentation, the fetal fluids and fetal membranes each have unique functions to ensure hematotrophic and histotrophic nutrition in support of growth and development of the fetus. The endocrine status of the pregnant female and her nutritional status are critical for successful establishment and maintenance of pregnancy. This review addresses the complexity of key mechanisms that are characteristic of successful reproduction in sheep and pigs and gaps in knowledge that must be the subject of research in order to enhance fertility and reproductive health of livestock species.  相似文献   
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AIM: To detect the expression and location of Norrin in mouse retina with oxygen-induced retinopathy (OIR). METHODS: Retinal neovascular angiogenesis of OIR mouse was observed by FITC-Dextran filled retinamounts. Norrin, VEGF mRNA expression was studied by RT-PCR in control mouse retina on postnatal days 7, 10, 12, 17 and in OIR mouse retina on postnatal days 7, 8, 12, 12.5, 13, 14, 15, 17 and 19. Norrin protein expression and location was observed by immunohistochemical methods. RESULTS: Retinal neovasculature was observed in OIR ischemic mouse on postnatal days 17. Norrin mRNA expression markedly increased in retina after hypoxia 12 hours, which was correlated with the upregulation of VEGF. The peak of increase in Norrin occurred at 24 hours, and levels then decreased slowly. Norrin was expressed in outer layers of retina of P15-17 OIR mice, and was not found in normal control mice retina. CONCLUSION: Increased levels of Norrin in OIR ischemic retina show temporal correlation with increased expression of VEGF. Increased Norrin locates in outer layers of retina. Norrin may play an important role in neovascular angiogenesis.  相似文献   
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AIM:To investigate whether human cytomegalovirus(HCMV) regulate human embryonic lung fibroblast(HEL) cell proliferation and apoptosis by activating NF-κB.METHODS:Immunohistochemistry and Western blot analysis were used to detect the NF-κB translocation and/or Bcl-2 and the levels of I-κBα during HCMV infection. Apoptotic cell were examined by flow cytometry, and the HEL cell proliferation was determined by MTT.RESULTS:The levels of NF-κB in the nucleus reached highly 48 h postinfection, and the levels of I-κBα were low 24 h postinfection. The activity of NF-κB was inhibited 120 h postinfection. The levels ofbcl-2was accorded with the activity of NF-κB. HCMV promoted HEL cells to proliferate before 72 h postinfection and induced apoptosis 120 h postinfection.CONCLUSION:NF-κB plays a role in HEL cell proliferation and apoptosis during HCMV infection, and it involves in the pathological mechanisms of diseases associated with HCMV infection.  相似文献   
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AIM: To study the function of the gene mRSD-9 . METHODS: The techniques of immunoprecipitation and immunofluorescence were applied to verify the interaction between mRSD-9 and endophlin 3. The ATP/GTP combined experiment and the clathrin releasing experiment were conducted to investigate the effect of mRSD-9 on endocytosis. RESULTS: Expressed Myc-mRSD-9 was precipitated by Flag-endophilin 3. Conversely, the expressed Flag-endophilin 3 was also precipitated by Myc-mRSD-9. Under laser scanning confocal microscope, mRSD-9-GFP fusion protein and endophilin 3-RFP fusion protein were observed to co-localize in CHO cells. The combination of mRSD-9 protein with ATP/GTP was found and was specific because no combination was detected using mutant ΔmRSD-9. In empty vector transfected group, the quantity of transferrin in red fluorescent expressed cells was roughly the same as the untransfected cells. In pDsRed1-N1-mRSD-9 transfected group, the quantity of transferrin in mRSD-9 protein expressed cells was obviously reduced. In pDsRed1-N1-ΔmRSD-9 transfected group, the quantity of transferrin in ΔmRSD-9 protein expressed cells was significantly increased. CONCLUSION: The protein coded by mRSD-9 gene can suppress endocytosis of transferrin.  相似文献   
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AIM and METHODS:To analysis the factor that involved in renal carcinogenesis, we used the bait gene AK001518 to screen GenBank. To understand the relationship between cell cycle related gene(CCRG) and p15, we did RT-PCR and Northern Blot experiments. Then we examined CCRG expression level in renal carcinogenesis. RESULTS:Gained a function unknown gene CCRG that was 67% a mino acid identical with the gene AK001518 that was regulated by p15. It was shown that the CCRG mRNA was dramatically decreased when p15 gene was over-expressed. CCRG expression level was much higher in tumor tissues and cells than normal tissues and cells. CONCLUSION:The novel gene CCRG expressed highly in the renal carcinoma, which might play a significant role in the renal carcinogenesis.  相似文献   
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