排序方式: 共有136条查询结果,搜索用时 31 毫秒
71.
Sehoon Keum Han Kyu Lee Pei-Lun Chu Matthew J. Kan Min-Nung Huang Carol J. Gallione Michael D. Gunn Donald C. Lo Douglas A. Marchuk 《PLoS genetics》2013,9(10)
During ischemic stroke, occlusion of the cerebrovasculature causes neuronal cell death (infarction), but naturally occurring genetic factors modulating infarction have been difficult to identify in human populations. In a surgically induced mouse model of ischemic stroke, we have previously mapped Civq1 to distal chromosome 7 as a quantitative trait locus determining infarct volume. In this study, genome-wide association mapping using 32 inbred mouse strains and an additional linkage scan for infarct volume confirmed that the size of the infarct is determined by ancestral alleles of the causative gene(s). The genetically isolated Civq1 locus in reciprocal recombinant congenic mice refined the critical interval and demonstrated that infarct size is determined by both vascular (collateral vessel anatomy) and non-vascular (neuroprotection) effects. Through the use of interval-specific SNP haplotype analysis, we further refined the Civq1 locus and identified integrin alpha L (Itgal) as one of the causative genes for Civq1. Itgal is the only gene that exhibits both strain-specific amino acid substitutions and expression differences. Coding SNPs, a 5-bp insertion in exon 30b, and increased mRNA and protein expression of a splice variant of the gene (Itgal-003, ENSMUST00000120857), all segregate with infarct volume. Mice lacking Itgal show increased neuronal cell death in both ex vivo brain slice and in vivo focal cerebral ischemia. Our data demonstrate that sequence variation in Itgal modulates ischemic brain injury, and that infarct volume is determined by both vascular and non-vascular mechanisms. 相似文献
72.
S.I. Jeong D.H. Kwak S. Lee Y.K. Choo W.H. Woo K.S. Keum B.K. Choi K.Y. Jung 《Phytomedicine》2005,12(9):648-655
This study describes a potent activity of Cnidium officinale Makino (Cnidii rhizoma) and Tabanus fulvus Meigan (Tabanus) as an inhibitor of high glucose-induced proliferation of glomerular mesangial cells (GMCs). Raising the ambient glucose concentration from 5.6 to 25 mM for 24 h caused a dramatic increase in [3H]thymidine incorporation, and these increases were attenuated by treatment of GMCs with the extracts of Cnidii rhizoma and Tabanus (2.5-20 microg/ml) in a dose-dependent manner. In contrast, extracts of Cnidii rhizoma or Tabanus (20 microg/ml) did not change the growth of GMCs cultured under normal glucose condition. To clarify the mechanism involved in anti-proliferative activity of these medicines, this study examined the effects of Cnidii rhizoma and Tabanus on high glucose-stimulated extracellular matrix (ECM) protein accumulation and transforming growth factor-beta1 (TGF-beta1) production. Exposure of GMCs to high glucose significantly stimulated the ECM protein, collagen and fibronectin, accumulation and TGF-beta1 secretion, and these changes were dramatically diminished by treatment of GMCs with extracts of Cnidii rhizoma or Tabanus (10 microg/ml). Taken together, these results indicate that Cnidii rhizoma and Tabanus inhibit the high glucose-induced GMC proliferation partially through suppressing the ECM accumulation and TGF-beta1 production, suggesting that these medicines may be a promising agent for treating the development and progression of diabetic glomerulopathy. 相似文献
73.
Carbachol regulates pacemaker activities in cultured interstitial cells of Cajal from the mouse small intestine 总被引:1,自引:0,他引:1
Keum Young So Sang Hun Kim Hong Moon Sohn Soo Jin Choi Shankar Prasad Parajuli Seok Choi Cheol Ho Yeum Pyung Jin Yoon Jae Yeoul Jun 《Molecules and cells》2009,27(5):525-531
We studied the effect of carbachol on pacemaker currents in cultured interstitial cells of Cajal (ICC) from the mouse small
intestine by muscarinic stimulation using a whole cell patch clamp technique and Ca2+-imaging. ICC generated periodic pacemaker potentials in the current-clamp mode and generated spontaneous inward pacemaker
currents at a holding potential of–70 mV. Exposure to carbachol depolarized the membrane and produced tonic inward pacemaker
currents with a decrease in the frequency and amplitude of the pacemaker currents. The effects of carbachol were blocked by
1-dimethyl-4-diphenylacetoxypiperidinium, a muscarinic M3 receptor antagonist, but not by methotramine, a muscarinic M2 receptor antagonist. Intracellular GDP-β-S suppressed the carbachol-induced effects. Carbachol-induced effects were blocked
by external Na+-free solution and by flufenamic acid, a non-selective cation channel blocker, and in the presence of thapsigargin, a Ca2+-ATPase inhibitor in the endoplasmic reticulum. However, carbachol still produced tonic inward pacemaker currents with the
removal of external Ca2+. In recording of intracellular Ca2+ concentrations using fluo 3-AM dye, carbachol increased intracellular Ca2+ concentrations with increasing of Ca2+ oscillations. These results suggest that carbachol modulates the pacemaker activity of ICC through the activation of non-selective
cation channels via muscarinic M3 receptors by a G-protein dependent intracellular Ca2+ release mechanism. 相似文献
74.
Park JY Chang JH Bae KS Lee KH Choi SJ Park JY Ryang YS Kim SK 《Cell biology international》2008,32(10):1207-1214
The present study was to see whether echinomycin-induced apoptosis would be NF-kappaB-dependent and if so, whether echinomycin would activate or inhibit NF-kappaB as well as resultant chemokine IL-8 expression. In HT-29 cells echinomycin activated NF-kappaB in time-dependent manner. EMSA in the presence of antibodies specific for p50 and p65 subunits indicated that echinomycin-induces the translocation of p50-p65 heterodimeric subunits of NF-kappaB. Levels of IkappaB were detected at initial echinomycin treatment and thereafter decreased, faintly seen after a 6h treatment. In contrast p-IkappaB levels were clearly detected throughout 6-24h of echinomycin treatment, albeit initially fainted. To clarify the role of NF-kappaB on IL-8 expression in echinomycin-mediated apoptosis of HT-29 cells, ELISA plus RT-PCR clearly showed that IL-8 production is inducible by echinomycin treatment. Using a specific inhibitor, IL-8 regulation at echinomycin treatment in HT-29 cells occurred via both caspase-3 and NF-kappaB-dependent signal pathway. To confirm whether two different pathways (NF-kappaB and caspase) would be coupled, only NF-kappaB inhibitor (PDTC) and caspase-3 specific inhibitor (Z-DEVD-FMK) together significantly attenuated echinomycin-initiated apoptosis of HT-29 cells, pretreatment of HT-29 cells with PDTC rarely affected echinomycin-induced caspase-3 activation. So echinomycin-induced apoptosis in HT-29 cells occurs via NF-kappaB activation independent of caspase-3 activation modulating the resultant-linked key chemokine IL-8 expression and echinomycin-induced apoptosis is NF-kappaB-dependant and directly related to NF-kappaB activation, consequently regulating IL-8 expression. 相似文献
75.
Fungal endophytes have been recorded in various plant species with a richness of diversity, and their presence plays an essential role in host plant protection against biotic and abiotic stresses. This study applied the Illumina MiSeq sequencing platform based on the amplification of fungal ribosomal ITS2 region to analyze fungal endophytic communities of two oak species (Quercus mongolica and Q. serrata) with different oak wilt disease susceptibilities in Korea. The results showed a total of 230,768 sequencing reads were obtained and clustered at a 97% similarity threshold into 709 operational taxonomic units (OTUs). The OTUs of Q. serrata were higher than that of Q. mongolica with the number of 617 OTUs and 512 OTUs, respectively. Shannon index also showed that Q. serrata had a significantly higher level of fungal diversity than Q. mongolica. Total of OTUs were assigned into 5 fungal phyla, 17 classes, 60 orders, 133 families, 195 genera, and 280 species. Ascomycota was the dominant phylum with 75.11% relative abundance, followed by Basidiomycota with 5.28%. Leptosillia, Aureobasidium and Acanthostigma were the most abundant genera detected in Q. serrata with the average relative abundance of 2.85, 2.76, and 2.19%, respectively. On the other hand, Peltaster, Cladosporium and Monochaetia were the most common genera detected in Q. mongolica with the average relative abundance of 4.83, 3.03, and 2.87%, respectively. Our results indicated that fungal endophytic communities were significantly different between two oak species and these differences could influence responses of host trees to oak wilt disease caused by Raffaelea quercus-mongolicae. 相似文献
76.
Neuroprotective effects of flavones on hydrogen peroxide-induced apoptosis in SH-SY5Y neuroblostoma cells 总被引:7,自引:0,他引:7
Neuroprotective effects of flavones were examined. Luteolin and apigenin exhibited neuroprotection against oxidative stress-induced cell death in SH-SY5Y cells. Free radical scavenging activity and neuroprotection assays revealed that flavones exerted their neuroprotective effects via the direct interaction with the apoptotic caspase pathway independently of their antioxidant activity. 相似文献
77.
Many components that are derived from medicinal or dietary plants possess potential chemopreventive properties. Curcumin, a yellow coloring agent from turmeric (Curcuma longa Linn, Zingiberaceae), possesses strong antimutagenic and anticarcinogenic activities. In this study, we have found that curcumin inhibits the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced nuclear factor kB (NF-kappaB) activation by preventing the degradation of the inhibitory protein IkBalpa; and the subsequent translocation of the p65 subunit in cultured human promyelocytic leukemia (HL-60) cells. Alternatively, curcumin repressed the TPA-induced activation of NF-kappaB through direct interruption of the binding of NF-kappaB to its consensus DNA sequences. Likewise, the TPA-induced DNA binding of the activator protein-1 (AP-1) was inhibited by curcumin pretreatment. 相似文献
78.
Measurement of blood viscosity using mass-detecting sensor 总被引:1,自引:0,他引:1
A newly designed mass-detecting capillary viscometer is extended to measure the viscosity of whole blood over a range of shear rates without the use of anticoagulants in a clinical setting. In the present study as proof of principle, a single measurement of liquid-mass variation with time replaces the flow rate and pressure drop measurements that are usually required for the operation of a capillary tube viscometer. Using a load cell and capillary, we measured the change of mass flowing through capillary tube with respect to the time, m(t), from which viscosity and shear rate were mathematically calculated. For water and adulterated bloods, excellent agreement was found between the results from the mass-detecting capillary viscometer and those from a commercially available rotating viscometer. Also, the mass-detecting capillary viscometer measured the viscosity of unadulterated whole blood without heparin or EDTA. This new method overcomes the drawbacks of conventional viscometers in the measurement of the whole blood viscosity. First, the mass-detecting capillary viscometer can accurately and consistently measure the unadulterated blood viscosity over a range of shear rates in less than 2 min without any anticoagulants. Second, this design provides simplicity (i.e. ease of operation, no moving parts, and disposable) and low cost. 相似文献
79.
Seung?Min?Yoo Ki?Chang?Keum So?Young?Yoo Jun?Yong?Choi Kyung?Hee?Chang Nae?Choon?Yoo Won?Min?Yoo June?Myung?Kim Duke?Lee Sang?Yup?LeeEmail author 《Biotechnology and Bioprocess Engineering》2004,9(2):93-99
Pathogens pose a significant threat to humans, animals, and plants. Consequently, a considerable effort has been devoted to
developing rapid, convenient, and accurate assays for the detection of these unfavorable organisms. Recently, DNA-microarray
based technology is receiving much attention as a powerful tool for pathogen detection. After the target gene is first selected
for the unique identification of microorganisms, species-specific probes are designed through bioinformatic analysis of the
sequences, which uses the information present in the databases. DNA samples, which were obtained from reference and/or clinical
isolates, are properly processed and hybridized with species-specific probes that are immobilized on the surface of the microarray
for fluorescent detection. In this study, we review the methods and strategies for the development of DNA microarray for pathogen
detection, with the focus on probe design. 相似文献
80.