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151.
Sondhi SM Jain S Dinodia M Shukla R Raghubir R 《Bioorganic & medicinal chemistry》2007,15(10):3334-3344
A number of pyrimidine derivatives (1-10) have been synthesized by condensation of 4-isothiocyanato-4-methylpentan-2-one with furfurylamine, histamine, 1-(3-aminopropyl)imidazole, 1-(3-aminopropyl)-2-pyrrolidinone, 2-aminobenzonitrile and 3-isothiocyanatobutanal with 1-(3-aminopropyl)-2-pyrrolidinone and 2-hydrazinopyridine under different reaction conditions. Various bispyrimidine derivatives (11-15) were obtained by condensation of 4-isothiocyanato-4-methylpentan-2-one with 2,4,8,10-tetraoxaspiro[5,5]undecane3,9-dipropamine (11'), 1,4-bis(3-aminopropyl)piperazine (13'), 3,5-diamino 1,2,4-triazole (15') and 3-isothiocyanatobutanal with 2,4,8,10-tetraoxaspiro[5,5]undecane 3,9-dipropamine, 1,4-bis(3-aminopropyl)piperazine. All these compounds were characterized by correct FT-IR, (1)H NMR, MS and elemental analysis. These compounds were screened for anti-inflammatory and analgesic activities. Anti-inflammatory activity of 3 is comparable while analgesic activity was found to be better than that of standard drug. 相似文献
152.
Wang ZZ Au P Chen T Shao Y Daheron LM Bai H Arzigian M Fukumura D Jain RK Scadden DT 《Nature biotechnology》2007,25(3):317-318
We describe the differentiation of human embryonic stem (hES) cells into endothelial cells using a scalable two-dimensional method that avoids an embryoid-body intermediate. After transplantation into severe combined immunodeficient (SCID) mice, the differentiated cells contributed to arborized blood vessels that integrated into the host circulatory system and served as blood conduits for 150 d. 相似文献
153.
Koenitzer JR Isbell TS Patel HD Benavides GA Dickinson DA Patel RP Darley-Usmar VM Lancaster JR Doeller JE Kraus DW 《American journal of physiology. Heart and circulatory physiology》2007,292(4):H1953-H1960
Hydrogen sulfide (H(2)S) has recently been shown to have a signaling role in vascular cells. Similar to nitric oxide (NO), H(2)S is enzymatically produced by amino acid metabolism and can cause posttranslational modification of proteins, particularly at thiol residues. Molecular targets for H(2)S include ATP-sensitive K(+) channels, and H(2)S may interact with NO and heme proteins such as cyclooxygenase. It is well known that the reactions of NO in the vasculature are O(2) dependent, but this has not been addressed in most studies designed to elucidate the role of H(2)S in vascular function. This is important, since H(2)S reactions can be dramatically altered by the high concentrations of O(2) used in cell culture and organ bath experiments. To test the hypothesis that the effects of H(2)S on the vasculature are O(2) dependent, we have measured real-time levels of H(2)S and O(2) in respirometry and vessel tension experiments, as well as the associated vascular responses. A novel polarographic H(2)S sensor developed in our laboratory was used to measure H(2)S levels. Here we report that, in rat aorta, H(2)S concentrations that mediate rapid contraction at high O(2) levels cause rapid relaxation at lower physiological O(2) levels. At high O(2), the vasoconstrictive effect of H(2)S suggests that it may not be H(2)S per se but, rather, a putative vasoactive oxidation product that mediates constriction. These data are interpreted in terms of the potential for H(2)S to modulate vascular tone in vivo. 相似文献
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Mishra RK Yamagishi T Vasanthi D Ohtsuka C Kondo T 《Genesis (New York, N.Y. : 2000)》2007,45(9):570-576
Temporal colinearity in mouse HoxD is dependent on repressive activity of sequences within the 5' end of the complex. We show that a 5-kb DNA fragment from this region represses transgenes when combined in mouse as well as in Drosophila melanogaster. Moreover, repressive activity in Drosophila depends on some members of the Polycomb-group (PcG) genes, for example, extra sex combs. We also showed direct association of these factors with the repressive fragment, both in transgenic flies and in the context of the native mouse HoxD complex. These results suggest that the global repressive region of the HoxD complex functions in two very different species and that some PcG genes are involved in establishing the early repressive state of the HoxD complex, thus contributing to temporal colinearity. 相似文献
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Jian Yang Robert A. Spicer Teresa E. V. Spicer Nan Crystal Arens Frédéric M. B. Jacques Tao Su Elizabeth M. Kennedy Alexei B. Herman David C. Steart Gaurav Srivastava Rakesh C. Mehrotra Paul J. Valdes Naresh C. Mehrotra Zhe‐Kun Zhou Jiang‐Shan Lai 《Global Ecology and Biogeography》2015,24(10):1113-1125