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691.
P2Y nucleotide receptor interaction with alpha integrin mediates astrocyte migration 总被引:2,自引:0,他引:2
Wang M Kong Q Gonzalez FA Sun G Erb L Seye C Weisman GA 《Journal of neurochemistry》2005,95(3):630-640
Astrocytes become activated in response to brain injury, as characterized by increased expression of glial fibrillary acidic protein (GFAP) and increased rates of cell migration and proliferation. Damage to brain cells causes the release of cytoplasmic nucleotides, such as ATP and uridine 5'-triphosphate (UTP), ligands for P2 nucleotide receptors. Results in this study with primary rat astrocytes indicate that activation of a G protein-coupled P2Y(2) receptor for ATP and UTP increases GFAP expression and both chemotactic and chemokinetic cell migration. UTP-induced astrocyte migration was inhibited by silencing of P2Y(2) nucleotide receptor (P2Y(2)R) expression with siRNA of P2Y(2)R (P2Y(2)R siRNA). UTP also increased the expression in astrocytes of alpha(V)beta(3/5) integrins that are known to interact directly with the P2Y(2)R to modulate its function. Anti-alpha(V) integrin antibodies prevented UTP-stimulated astrocyte migration, suggesting that P2Y(2)R/alpha(V) interactions mediate the activation of astrocytes by UTP. P2Y(2)R-mediated astrocyte migration required the activation of the phosphatidylinositol-3-kinase (PI3-K)/protein kinase B (Akt) and the mitogen-activated protein kinase/extracellular signal-regulated kinase (MEK/ERK) signaling pathways, responses that also were inhibited by anti-alpha(V) integrin antibody. These results suggest that P2Y(2)Rs and their associated signaling pathways may be important factors regulating astrogliosis in brain disorders. 相似文献
692.
A human T-cell leukemia virus type 1 regulatory element enhances the immunogenicity of human immunodeficiency virus type 1 DNA vaccines in mice and nonhuman primates 总被引:6,自引:0,他引:6
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Barouch DH Yang ZY Kong WP Korioth-Schmitz B Sumida SM Truitt DM Kishko MG Arthur JC Miura A Mascola JR Letvin NL Nabel GJ 《Journal of virology》2005,79(14):8828-8834
Plasmid DNA vaccines elicit potent and protective immune responses in numerous small-animal models of infectious diseases. However, their immunogenicity in primates appears less potent. Here we investigate a novel approach that optimizes regulatory elements in the plasmid backbone to improve the immunogenicity of DNA vaccines. Among various regions analyzed, we found that the addition of a regulatory sequence from the R region of the long terminal repeat from human T-cell leukemia virus type 1 (HTLV-1) to the cytomegalovirus (CMV) enhancer/promoter increased transgene expression 5- to 10-fold and improved cellular immune responses to human immunodeficiency virus type 1 (HIV-1) antigens. In cynomolgus monkeys, DNA vaccines containing the CMV enhancer/promoter with the HTLV-1 R region (CMV/R) induced markedly higher cellular immune responses to HIV-1 Env from clades A, B, and C and to HIV-1 Gag-Pol-Nef compared with the parental DNA vaccines. These data demonstrate that optimization of specific regulatory elements can substantially improve the immunogenicity of DNA vaccines encoding multiple antigens in small animals and in nonhuman primates. This strategy could therefore be explored as a potential method to enhance DNA vaccine immunogenicity in humans. 相似文献
693.
694.
Qiu YC Zhou RH Kong XY Zhang SS Jia JZ 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,111(8):1524-1531
A powdery mildew resistance gene from Triticum urartu Tum. accession UR206 was successfully transferred into hexaploid wheat (Triticum aestivum L.) through crossing and backcrossing. The F1 plants, which had 28 chromosomes and an average of 5.32 bivalents and 17.36 univalents in meiotic pollen mother cells (PMC),
were obtained through embryos rescued owing to shriveling of endosperm in hybrid seed of cross Chinese Spring (CS) × UR206.
Hybrid seeds were produced through backcrossing F1 with common wheat parents. The derivative lines had normal chromosome numbers and powdery mildew resistance similar to the
donor UR206, indicating that the powdery mildew resistance gene originating from T. urartu accession UR206 was successfully transferred and expressed in a hexaploid wheat background. Genetic analysis indicated that
a single dominant gene controlled the powdery mildew resistance at the seedling stage. To map and tag the powdery mildew resistance
gene, 143 F2 individuals derived from a cross UR206 × UR203 were used to construct a linkage map. The resistant gene was mapped on the
chromosome 7AL based on the mapped microsatellite makers. The map spanned 52.1 cM and the order of these microsatellite loci
agreed well with the established microsatellite map of chromosome arm 7AL. The resistance gene was flanked by the microsatellite
loci Xwmc273 and Xpsp3003, with the genetic distances of 2.2 cM and 3.8 cM, respectively. On the basis of the origin and chromosomal location of the
gene, it was temporarily designated PmU. 相似文献
695.
Urocortin(Ucn)是一含40个氨基酸的多肽,属于促肾上腺皮质激素释放激素(CRH)家族的新成员。它不仅在脑组织中表达,而且也存在于外周组织,特别是在心脏中高表达。Ucn有高效的心血管作用,它可以降血压、增强心脏收缩力,还可提高心肌细胞对缺血-再灌注损伤的抵抗力。本文集中讨论了Ucn的心血管作用及其作用机制的研究进展。 相似文献
696.
Chan NN Kong AP Chan JC 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2005,26(3):51-57
The Metabolic syndrome (MetS), obesity and type 2 diabetes are growing global epidemics especially in Asian populations. In light of the differences in body build between people from the West and the East, definitions of obesity in Asians have been modified accordingly. Data from Hong Kong, an epitome of future China, may provide important insight into the potential interactions between nature and nurture in this global epidemic. Now supported by large scale studies, it is clear that Chinese type 2 diabetic patients exhibit marked phenotypic heterogeneity in terms of risk profiles and complications. Apart from genetic differences, age- and stress-related neurohormonal dysregulation may also contribute to the increasing prevalence of obesity, type 2 diabetes and MetS in Chinese living in modern societies. In this mini-review, we aim to summarise findings from our group collected during the last decade in our attempt to understand this epidemic and to develop evidence-based care models to reduce the impact of this health hazard. 相似文献
697.
Ahn NS Hu H Park JS Park JS Kim JS An S Kong G Aruoma OI Lee YS Kang KS 《Mutation research》2005,579(1-2):189-199
Although 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has a variety of carcinogenic and noncarcinogenic effects in experimental animals, its role in human carcinogenicity remain controversial. A simian virus 40-immortalized cell line from normal human breast epithelial cells with stem cells and luminal characteristics (M13SV1) was used to study whether TCDD can induce AIG positive colony formation and cause increased cell numbers in a inverted U-shaped dose–response manner. TCDD activated Akt, ERK2, and increased the expression of CYP1A1, PAI-2, IL-lb mRNA, and ERK2 protein levels. TCDD was able to increased phosphorylation and expression of ERK2 in same dose–response manner as AIG positive colony formation. Thus, TCDD induced tumorigenicity in M13SV1, possibly through the phosphorylation of ERK2 and/or Akt. Further, cDNA microarray with 7448 sequence-verified clones was used to profile various gene expression patterns after treatment of TCDD. Three clear patterns could be delineated: genes that were dose-dependently up-regulated, genes expressed in either U-shape and/or inverted U-shape. The fact that these genes are intrinsically related to breast epithelial cell proliferation and survival clearly suggests that they may be involved in the TCDD-induced breast tumorigenesis. 相似文献
698.
699.
To find a simple and reliable oxygen electrode-based method to estimate the values of alternative pathway activity (V
alt) and its contribution to total respiration V
alt/V
t) in aged potato (Solanum tuberosum L.) tuber slices, we compared conventional hydroxamate-inhibiting method, improved hydroxamate-inhibiting method with 2,6-dichlorophenol indophenol (DCPIP), and the oxygen isotope discrimination (OID) method. The values of V
alt and V
alt/V
t obtained with an improved hydroxamate-inhibiting method with DCPIP in 12-h- and 24-h-aged slices were about twice higher than those with the conventional hydroxamate-inhibiting method. Only a relatively small difference in the values of V
alt and V
alt/V
t obtained by the OID method and the improved hydroxamate-inhibiting method with DCPIP in 12-h and 24-h-aged slices was observed. These results indicated that the improved hydroxamate-inhibiting method with DCPIP could be considered as a new, simple, and reliable technique for the noninvasive assay of the AP activity.From Fiziologiya Rastenii, Vol. 52, No. 2, 2005, pp. 311–315.Original English Text Copyright © 2005 by Hou, Zhou, Kong, Liang, Zhang.This article was submitted by the authors in English.This revised version was published online in April 2005 with a corrected cover date. 相似文献
700.
Inhibition of respiratory syncytial virus infection with intranasal siRNA nanoparticles targeting the viral NS1 gene 总被引:17,自引:0,他引:17
Zhang W Yang H Kong X Mohapatra S San Juan-Vergara H Hellermann G Behera S Singam R Lockey RF Mohapatra SS 《Nature medicine》2005,11(1):56-62
Respiratory syncytial virus (RSV) infection is one of the major causes of respiratory tract infection for which no vaccine or antiviral treatment is available. The RSV NS1 protein seems to antagonize the host interferon (IFN) response; however, its mechanism is unknown. Here, we used a plasmid-borne small interfering RNA targeting the NS1 gene (siNS1) to examine the role of NS1 in modulating RSV infection. RSV replication was reduced in A549 cells, but not IFN-deficient Vero cells, transfected with siNS1. siNS1 induced upregulated expression of IFN-beta and IFN-inducible genes in A549 cells. siNS1-transfected human dendritic cells, upon RSV infection, produced elevated type-1 IFN and induced differentiation of naive CD4+ T cells to T helper type 1 (TH1) cells. Mice treated intranasally with siNS1 nanoparticles before or after infection with RSV showed substantially decreased virus titers in the lung and decreased inflammation and airway reactivity compared to controls. Thus, siNS1 nanoparticles may provide an effective inhibition of RSV infection in humans. 相似文献