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11.
Global gene expression analysis to identify molecular markers of uterine receptivity and embryo implantation 总被引:19,自引:0,他引:19
Reese J Das SK Paria BC Lim H Song H Matsumoto H Knudtson KL DuBois RN Dey SK 《The Journal of biological chemistry》2001,276(47):44137-44145
Infertility and spontaneous pregnancy losses are an enduring problem to women's health. The establishment of pregnancy depends on successful implantation, where a complex series of interactions occurs between the heterogeneous cell types of the uterus and blastocyst. Although a number of genes are implicated in embryo-uterine interactions during implantation, genetic evidence suggests that only a small number of them are critical to this process. To obtain a global view and identify novel pathways of implantation, we used a dual screening strategy to analyze the expression of nearly 10,000 mouse genes by microarray analysis. Comparison of implantation and interimplantation sites by a conservative statistical approach revealed 36 up-regulated genes and 27 down-regulated genes at the implantation site. We also compared the uterine gene expression profile of progesterone-treated, delayed implanting mice to that of mice in which delayed implantation was terminated by estrogen. The results show up-regulation of 128 genes and down-regulation of 101 genes after termination of the delayed implantation. A combined analysis of these experiments showed specific up-regulation of 27 genes both at the implantation site and during uterine activation, representing a broad diversity of molecular functions. In contrast, the majority of genes that were decreased in the combined analysis were related to host immunity or the immune response, suggesting the importance of these genes in regulating the uterine environment for the implanting blastocyst. Collectively, we identified genes with recognized roles in implantation, genes with potential roles in this process, and genes whose functions have yet to be defined in this event. The identification of unique genetic markers for the onset of implantation signifies that genome-wide analysis coupled with functional assays is a promising approach to resolve the molecular pathways required for successful implantation. 相似文献
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Kandasamy Thamilarasi Kumari Kanchan Ghosh Jyotirmoy Tribhuvan Kishor U. Lohot Vaibhav D. Gargi Madhuranjana Ghosal S. 《Journal of plant biochemistry and biotechnology.》2020,29(3):461-472
Journal of Plant Biochemistry and Biotechnology - Pigeonpea, an important legume crop is a good host plant for lac cultivation in North East India. In the present study, sixty-three polymorphic EST... 相似文献
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Dey Chyi Sheu Jan Yi Chang Chung Yih Wang Chang Ta Wu Chen Ji Huang 《Bioprocess and biosystems engineering》2013,36(11):1745-1751
High-purity fructooligosaccharides (FOS) were produced from sucrose by an innovative process incorporating immobilized Aspergillus japonicus and Pichia heimii cells. Intracellular FTase of A. japonicus converted sucrose into FOS and glucose, and P. heimii fermented glucose mainly into ethanol. The continuous production of FOS was carried out using a tanks-in-series bioreactor consisting of three stirred tanks. When a solution composed of 1 g L?1 yeast extract and 300 g L?1 sucrose was fed continuously to the bioreactor at a dilution rate of 0.1 h?1, FOS at a purity of up to 98.2 % could be achieved and the value-added byproduct ethanol at 79.6 g L?1 was also obtained. One gram of sucrose yielded 0.62 g FOS and 0.27 g ethanol. This immobilized dual-cell system was effective for continuous production of high-purity FOS and ethanol for as long as 10 days. 相似文献
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Scott J Diede Zizhen Yao C Chip Keyes Ashlee E Tyler Joyoti Dey Christopher S Hackett Katrina Elsaesser Christopher J Kemp Paul E Neiman William A Weiss James M Olson Stephen J Tapscott 《Epigenetics》2013,8(12):1254-1260
Genetic and epigenetic alterations are essential for the initiation and progression of human cancer. We previously reported that primary human medulloblastomas showed extensive cancer-specific CpG island DNA hypermethylation in critical developmental pathways. To determine whether genetically engineered mouse models (GEMMs) of medulloblastoma have comparable epigenetic changes, we assessed genome-wide DNA methylation in three mouse models of medulloblastoma. In contrast to human samples, very few loci with cancer-specific DNA hypermethylation were detected, and in almost all cases the degree of methylation was relatively modest compared with the dense hypermethylation in the human cancers. To determine if this finding was common to other GEMMs, we examined a Burkitt lymphoma and breast cancer model and did not detect promoter CpG island DNA hypermethylation, suggesting that human cancers and at least some GEMMs are fundamentally different with respect to this epigenetic modification. These findings provide an opportunity to both better understand the mechanism of aberrant DNA methylation in human cancer and construct better GEMMs to serve as preclinical platforms for therapy development. 相似文献
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Debashree De Piyali Datta Chakraborty Jyotirmoy Mitra Kanika Sharma Somnath Mandal Aneesha Das Saikat Chakrabarti Debasish Bhattacharyya 《PloS one》2013,8(3)
An aqueous extract of human placenta exhibits strong gelatinase/collagenase activity in zymography. 2-D gel electrophoresis of the extract with gelatin zymography in the second dimension displayed a single spot, identified as ubiquitin-like component upon MALDI/TOF MS/MS analysis. Immunoblot indicated presence of ubiquitin and absence of collagenase in the extract. Collagenase activity of the ubiquitin-like component was confirmed from the change in solubility of collagen in aqueous buffer, degradation of collagen by size-exclusion HPLC and atomic force microscopy. Quantification with DQ-gelatin showed that the extract contains 0.04 U/ml of collagenase activity that was inhibited up to 95% by ubiquitin antibody. Ubiquitin from bovine erythrocytes demonstrated mild collagenase activity. Bioinformatics studies suggest that placental ubiquitin and collagenase follow structurally divergent evolution. This thermostable intrinsic collagenase activity of placental extract might have wide physiological relevance in degrading and remodeling collagen as it is used as a drug for wound healing and pelvic inflammatory diseases. 相似文献
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Isothermal calorimetry (ITC) is efficient in characterizing and recognizing both high affinity and low affinity intermolecular interactions quickly and accurately. Adriamycin (ADR) and daunomycin (DNM) are the two anticancer drugs whose activity is achieved mainly by intercalation with DNA. During chemotherapy, normal human genomic DNA and mutated DNA from K562 leukemic cells show different thermodynamic properties and binding affinities on interaction with ADR and DNM when followed by ITC. Normal DNA shows more than one step in kinetic analysis, which could be attributed to outside binding, intercalation and reshuffling as suggested by Chaires et al. (1985); whereas K562 DNA fits a different binding pattern with higher binding affinities (by one order or more) compared to normal DNA. Structural properties of the interaction were followed by laser Raman spectroscopy, where difference in structure was apparent from the shifts in marker B DNA Raman bands (Ling et al., 2005). A correlation of thermodynamic contribution and structural data reveals step wise changes in normal genomic DNA conformation on drug binding. The overall structural change is higher in normal DNA–DNM interaction suggesting a partial B to A transition on drug binding. Such large changes were not observed for K562 DNA–DNM interaction which showed B to A transition properties in native from itself corroborating with our earlier findings (Ghosh et al., 2012). 相似文献
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Ruth Goldschmidt Pablo M. Arce Omar M. Khdour Valérie C. Collin Sriloy Dey Jennifer Jaruvangsanti David M. Fash Sidney M. Hecht 《Bioorganic & medicinal chemistry》2013,21(4):969-978
Two new aza analogues of the neuroprotective agent idebenone have been synthesized and characterized. Their antioxidant activity, and ability to augment ATP levels have been evaluated in several different cell lines having suboptimal mitochondrial function. Both compounds were found to be good ROS scavengers, and to protect the cells from oxidative stress induced by glutathione depletion. The compounds were more effective than idebenone in neurodegenerative disease cells. These novel pyrimidinol derivatives were also shown to augment ATP levels in coenzyme Q10-deficient human lymphocytes. The more lipophilic side chains attached to the pyrimidinol redox core in these compounds resulted in less inhibition of the electron transport chain and improved antioxidant activity. 相似文献