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761.
The outcome of human pregnancy depends on the differentiation of cytotrophoblasts, specialized placental cells that physically connect the embryo/fetus to the mother. As cytotrophoblasts differentiate, they acquire tumor-like characteristics that enable them to invade the uterus. In a novel feedback loop, the increasingly higher levels of oxygen they encounter within the uterine wall influence their differentiation into vascular-like cells. Together, the invasive and cell surface properties of cytotrophoblasts enable them to form vascular connections with uterine blood vessels that divert maternal blood flow to the placenta, a critical hurdle in pregnancy. It is therefore important to understand how cytotrophoblasts respond to changes in oxygen tension. Here we used a proteomics approach, two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) combined with mass spectrometry, to characterize the protein repertoire of first trimester human cytotrophoblasts that were maintained under standard tissue culture conditions (20% O(2)). 2-D PAGE showed a unique protein map as compared to placental fibroblasts and human JEG-3 choriocarcinoma cells. Mass spectrometry allowed the identification of 43 spots on the cytotrophoblast map. Enzymes involved in glycolysis and responses to oxidative stress, as well as the 14-3-3 signaling/adapter proteins, were particularly abundant. Hypoxia in vitro (2% O(2)) produced discrete changes in the expression of a subset of proteins in all the aforementioned functional categories. Together, these data offer new information about the early gestation cytotrophoblast protein repertoire and the generalized mechanisms the cells use to respond to changes in oxygen tension at the maternal-fetal interface.  相似文献   
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Melia azedazach, a plant for forestation, is popular in many countries. Development of triploid M. azedazach varieties will provide additional advantages, such as faster growth, higher biomass, and; therefore, increased productivity. In this study, we aimed to develop triploid M. azedarach L. by immature endosperm tissue culture. After 22 days of initiation of cultures, calli of the endosperm were visible. After 50 days cultured on Murashige and Skoog (MS) medium supplemented with 2.0 mg/l NAA and 1.0 mg/l BAP, maximum of callus induction rate from the immature endosperm with seed coat was obtained at 55.9%. The highest frequency of shoot induction from endosperm-derived callus was 98% and average of 16.7 shoots per explant on the medium supplemented with 1.5 mg/l BAP and 0.5 mg/l NAA after 42 days. A single shoot was detached from the multi-shoots and transferred to the rooting medium supplemented with 0.5 mg IBA, inducing root formation with 96.6% and with average of 5.8 roots per plantlet after 28 days. The plantlets transferred to polythene hycotrays containing soil and sand (mixture 1:1) in greenhouse showed 100% survival after transplantation. The endosperm-derived plantlets were 100% triploids as evidenced by flow cytometry analysis. Creating triploid M. azedazach plants by regenerating directly from endosperm (3n) described in this work required only 5 months whereas the traditional method of generating triploids through crossing between tetraploid (4n) and diploid (2n) plants could take up to 12 years.  相似文献   
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Applied Microbiology and Biotechnology - Japanese cedar pollinosis is a seasonal allergic disease caused by two major pollen allergens: Cry j 1 and Cry j 2 antigens. To develop an oral vaccine to...  相似文献   
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In this research several series of novel dioxygenated ring fused 4-anilinoquinazolines (10a-d) and 4-anilinoquinazoline-substituted triazole hybrid compounds (1114) have been designed and synthesized. Their biological significance was highlighted by evaluating in vitro for anticancer activities, wherein several compounds displayed excellent activity specifically against three human cancer cell lines (KB, epidermoid carcinoma; HepG2, hepatoma carcinoma; SK-Lu-1, non-small lung cancer). Especially, compound 13a exhibited up to 100-fold higher cytotoxicity in comparison with erlotinib. Docking the most cytotoxic compounds (11d, 13a, 13b, and 14c) into the ATP binding site of different EGFR tyrosine kinase domains was perfomed to predict the analogous binding mode of these compounds to the EGFR targets.  相似文献   
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The minD gene encoding an inhibitor cell division MinD homolog from Lactobacillus acidophilus VTCC-B-871 was cloned. We showed that there were 97 % homology between minD genes of L. acidophilus VTCC-B-871 and Lactobacillus rhamnosus GG and Lactobacillus rhamnosus Lc705. Based on the analysis of the DNA sequence data from the L. rhamnosus genome project and sequenced minD gene of L. acidophilus VTCC-B-871, a pair of primers was designed to identified the different minD genes from L. acidophilus ATCC 4356, L. rhamnosus ATCC 11443. Besides, the polymerase chain reaction product of minD gene was also obtained in L. rhamnosus PN04, a strain was isolated from Vietnamese Hottuynia cordata Thunb. In addition, we performed a phylogenetic analysis of the deduced amino acid sequence of MinD homologs from L. acidophilus VTCC-B-871 with the other strains and compared the predicted three-dimension structure of L. acidophilus VTCC-B-871 MinD with Escherichia coli MinD, there are similarity that showed evolution of these strains. The overexpression of L. acidophilus VTCC-B-871 MinD in E. coli led to cell filamentation in IPTG and morphology changes in different sugar stresses, interestingly. The present study is the first report characterizing the Lactobacilus MinD homolog that will be useful in probiotic field.  相似文献   
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