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991.
Mukaiyama H Nishimura T Kobayashi S Komatsu Y Kikuchi S Ozawa T Kamada N Ohnota H 《Bioorganic & medicinal chemistry》2008,16(2):909-921
To improve the in vitro potency of the c-Src inhibitor 1a and to address its hERG liability, a structure-activity study was carried out, focusing on two regions of the lead compound. The blockade of the delayed cardiac current rectifier K(+) (I(Kr)) channel was overcome by replacing the ethylenediamino group with an amino alcohol group at the 7-position. In addition, modifying the substituents at the 5-position and the side chain groups on the amino alcohols at the 7-position enhanced the intracellular c-Src inhibitory activity and increased central nervous system (CNS) penetration. In the present study, 6l exhibited significant in vivo efficacy in a middle cerebral artery (MCA) occlusion model in rats. 相似文献
992.
Asaki T Aoki T Hamamoto T Sugiyama Y Ohmachi S Kuwabara K Murakami K Todo M 《Bioorganic & medicinal chemistry》2008,16(2):981-994
A series of 1,3-dioxane carboxylic acid derivatives was synthesized and evaluated for human PPAR transactivation activity. Structure-activity relationships on the phenyloxazole moiety of the lead compound 3 revealed that the introduction of small hydrophobic substituents at the 4-position of the terminal phenyl ring increased the PPARalpha agonist activity, and that the oxazole heterocycle was essential to the maintenance of both potency and PPARalpha subtype-selectivity. This investigation led to the identification of 14d (NS-220) and 14i as highly potent and selective human PPARalpha agonists. In KK-A(y) type 2 diabetic mice, these compounds significantly lowered plasma triglyceride and very-low-density plus low-density lipoprotein cholesterol levels while simultaneously raising HDL cholesterol levels. Our results suggest that highly potent and subtype-selective PPARalpha agonists will be promising drugs for the treatment of metabolic disorders in type 2 diabetes. 相似文献
993.
994.
The candidate sour taste receptor, PKD2L1, is expressed by type III taste cells in the mouse 总被引:3,自引:0,他引:3
Kataoka S Yang R Ishimaru Y Matsunami H Sévigny J Kinnamon JC Finger TE 《Chemical senses》2008,33(3):243-254
The transient receptor potential channel, PKD2L1, is reported to be a candidate receptor for sour taste based on molecular biological and functional studies. Here, we investigated the expression pattern of PKD2L1-immunoreactivity (IR) in taste buds of the mouse. PKD2L1-IR is present in a few elongate cells in each taste bud as reported previously. The PKD2L1-expressing cells are different from those expressing PLCbeta2, a marker of Type II cells. Likewise PKD2L1-immunoreactive taste cells do not express ecto-ATPase which marks Type I cells. The PKD2L1-positive cells are immunoreactive for neural cell adhesion molecule, serotonin, PGP-9.5 (ubiquitin carboxy-terminal transferase), and chromogranin A, all of which are present in Type III taste cells. At the ultrastructural level, PKD2L1-immunoreactive cells form synapses onto afferent nerve fibers, another feature of Type III taste cells. These results are consistent with the idea that different taste cells in each taste bud perform distinct functions. We suggest that Type III cells are necessary for transduction and/or transmission of information about "sour", but have little or no role in transmission of taste information of other taste qualities. 相似文献
995.
Harada K Tanaka H Komori S Tsuji Y Nagata K Tsutsui H Koyama K 《Microbiology and immunology》2008,52(6):297-304
U. urealyticum, a member of the family Mycoplasmataceae, is often detected in the vagina of pregnant women. In this study, the possible association of ureaplasmal infection with preterm delivery was examined, as was the capacity of ureaplasmal LP to stimulate monocytes in vitro to produce pro-inflammatory cytokines relevant to preterm delivery. A hundred cases of normal delivery and 45 cases of preterm delivery were randomly selected. A mAb against U. urealyticum urease, that selectively and positively stained it in vaginal secretions of infected women but not in those of uninfected women, was generated. The preterm delivery group showed a significantly higher incidence of vaginal infection with this bacteria than the normal delivery group. Since the LP of Mycoplasma has potent biological activity, ureaplasmal LP was extracted. THP-1 cells, and human monocytic cells, produced IL-8, a potent pro-inflammatory cytokine associated with preterm delivery, and showed apoptotic cell death in response to the LP in vitro. These results suggest that U. urealyticum infection might play a causative role in preterm delivery via LP-induced IL-8 production and apoptosis. 相似文献
996.
Tokuda H Takai S Matsushima-Nishiwaki R Hanai Y Adachi S Minamitani C Mizutani J Otsuka T Kozawa O 《Prostaglandins, leukotrienes, and essential fatty acids》2008,79(1-2):41-46
We have previously reported that prostaglandin D2 (PGD2) stimulates interleukin-6 (IL-6), a potent bone resorptive agent, in osteoblast-like MC3T3-E1 cells. In the present study, we investigated whether Rho-kinase is implicated in the PGD2-stimulated IL-6 synthesis in MC3T3-E1 cells. PGD2 time-dependently induced the phosphorylation of myosin phosphatase targeting subunit (MYPT-1), a Rho-kinase substrate. Y27632, a specific Rho-kinase inhibitor, significantly reduced the PGD2-stimulated IL-6 synthesis as well as the MYPT-1 phosphorylation. Fasudil, another inhibitor of Rho-kinase, suppressed the PGD2-stimulated IL-6 synthesis. The PGD2-stimulated IL-6 synthesis was reduced by PD98059, a MEK inhibitor, and SB203580, an inhibitor of p38 mitogen-activated protein (MAP) kinase, but not SP600125, an inhibitor of stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK). However, Y27632 and fasudil failed to affect the PGD2-induced phosphorylation of p44/p42 MAP kinase. On the other hand, Y27632 as well as fasudil markedly attenuated the PGD2-induced phosphorylation of p38 MAP kinase. In addition, PGD2 additively induced IL-6 synthesis in combination with endothelin-1 which induces IL-6 synthesis through p38 MAP kinase regulated by Rho-kinase. These results strongly suggest that Rho-kinase regulates PGD2-stimulated IL-6 synthesis via p38 MAP kinase activation in osteoblasts. 相似文献
997.
998.
999.
Oozono S Yamauchi N Nishimura K Matsumoto K Watanabe R Kubota K Aramaki S Sato F Wood C Soh T Kizaki K Hattori MA 《Journal of experimental zoology. Part B. Molecular and developmental evolution》2008,310(8):642-649
Implantation serine protease (ISP) was first identified in the uteri of pregnant mice. It is thought that ISP may have an important role in the initiation of implantation. However, the expression status and detailed functions of ISP remain unclear. In this study, the expression of ISP was investigated in the rat uterus. The analysis of two rat genes registered in GenBank, accession nos. XM_220240 and XM_577076, exhibited high identities to the mouse ISP2 genes, respectively at an mRNA level. We labeled the former as rISP2a and the latter as rISP2b. Using RT-PCR, we found that both genes were expressed in the uterus. Specifically, rISP2a mRNA was detected in the uterus throughout pregnancy, whereas rISP2b mRNA was only expressed in the uterus from day 5 of pregnancy until the end of gestation. Expression of both genes was observed specifically within the endometrial gland epithelium. Furthermore, rISP2a was also observed to be expressed in the fetus and placenta, whereas rISP2b expression was observed in the fetus but not in the placenta. An expressional signal of the rISP2a gene was observed in the spongiotrophoblasts, giant cells and decidual endometrium in the placenta. In the embryo, the ventral specific region was positive in rISP2a and rISP2b gene expression. These findings indicate the possibility that the presently examined genes with high identity to mouse ISP2 may play some role not only during the implantation phase, but also in the development of the placenta and embryo. 相似文献
1000.
Differences in endemic insect assemblages among vegetation types on a small island of the oceanic Ogasawara Islands 总被引:1,自引:0,他引:1
Shinji SUGIURA Tomoyuki TSURU Yuichi YAMAURA Motohiro HASEGAWA Hiroshi MAKIHARA Shun'ichi MAKINO 《Entomological Science》2008,11(2):131-141
Natural vegetation is often replaced by invasive alien plants on isolated oceanic islands. To determine how invasive alien plants affect insect diversity, we compared flying insects captured using Malaise traps among different vegetation types on a small island (Nishijima; 0.49 km2) in the oceanic Ogasawara (Bonin) Islands in the north‐western Pacific. The numbers of individuals and species, and the species composition of pollinators (bees), predators (wasps) and wood borers (cerambycid, mordellid and elaterid beetles) were compared among three vegetation types: Casuarina equisetifolia (an invasive alien tree) forest, natural forest and natural grassland (forest edge), during two seasons (June and October–November 2005). In traps, 80.0, 66.7, 87.5, 85.7 and 100.0% of bee, wasp, cerambycid, mordellid and elaterid beetle species, respectively, were endemic to the Ogasawara Islands. Grassland had the highest wasp and bee species richness, whereas natural forest had the highest species richness of wood‐boring beetles. The C. equisetifolia forest had the poorest species richness for most insect groups (except mordellid beetles). More individuals of most insect groups (except bees) were captured in June than in October–November. More individual bees and wasps were captured in grassland than in forests, whereas more individual mordellid and elaterid beetles were captured in forests than in grassland. The number of cerambycid individuals did not differ among vegetation types. Redundancy analysis suggested that most insect species preferred natural forest or grassland to alien forest. Therefore, further invasion of natural grassland and forest by the alien tree C. equisetifolia may negatively affect the endemic insect fauna of Nishijima. 相似文献