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991.
Chin-Man Wang Huei-Huang Ho Su-Wei Chang Yeong-Jian Jan Wu Jing-Chi Lin Pi-Yueh Chang Jianming Wu Ji-Yih Chen 《Arthritis research & therapy》2012,14(3):R125
IntroductionAnkylosing spondylitis (AS) is a familial, heritable disease specified by syndesmophyte formation leading to an ankylosed spine. Endoplasmic reticulum aminopeptidase 1 (ERAP1) genetic variations have been widely proved to be associated with AS in several ethnic populations. The aim of this study was to investigate whether ERAP1 single nucleotide polymorphisms (SNPs) are associated with AS susceptibility and disease severity in Taiwanese.MethodsFour ERAP1 SNPs (rs27037, rs27980, rs27044 and rs30187) were genotyped in 797 Taiwanese AS patients and 1,150 healthy controls. Distributions of genotype and alleles were compared between AS patients and healthy controls, and among AS patients stratified by clinical parameters.ResultsThe SNP rs27037T allele appeared to be a risk factor for AS susceptibility (P = 5.5 × 10-5, OR 1.30, 95% CI: 1.15 to 1.48; GT+TT vs. GG P = 9.3 × 10-5, OR 1.49, 95% CI: 1.22 to 1.82). In addition, the coding SNP (cSNP) rs27044G allele (P = 1.5 × 10-4, OR 1.28, 95% CI: 1.13 to 1.46; CG+GG vs. CC, P = 1.7 × 10-3, OR 1.44, 95% CI: 1.15 to 1.81) and the cSNP rs30187T allele (P = 1.7 × 10-3, OR 1.23, 95% CI: 1.08 to 1.40; CT+TT vs. CC P = 6.1 × 10-3, OR 1.38, 95% CI: 1.10 to 1.74) were predisposing factors for AS. Notably, the rs27044G allele carriers (CG+GG vs. CC, P = 0.015, OR 1.59, 95% CI: 1.33 to 2.30) and rs30187T allele carriers (CT+TT vs. CC, P = 0.011, OR 1.63, 95% CI: 1.12 to 2.38) were susceptible to syndesmophyte formation in AS patients. Furthermore, two cSNPs (rs27044 and rs30187) strongly associated with HLA-B27 positivity in AS patients. Finally, the ERAP1 SNP haplotype TCG (rs27037T/rs27980C/rs27044G) is a major risk factor for AS (adjusted P <0.00001, OR 1.38, 95% CI: 1.12 to 1.58) in Taiwanese.ConclusionsThis study provides the first evidence of ERAP1 SNPs involving syndesmophyte formation. The interactions between ERAP1 SNPs and HLA-B27 play critical roles in pMHC I pathway processing contributing to the pathogenesis of AS in multiple populations. 相似文献
992.
Bong Cho Kim Hyung Chul Lee Je‐Jung Lee Chang‐Min Choi Dong‐Kwan Kim Jae Cheol Lee Young‐Gyu Ko Jae‐Seon Lee 《The EMBO journal》2012,31(22):4289-4303
Premature senescence, a key strategy used to suppress carcinogenesis, can be driven by p53/p21 proteins in response to various stresses. Here, we demonstrate that Wig1 plays a critical role in this process through regulation of p21 mRNA stability. Wig1 controls the association of Argonaute2 (Ago2), a central component of the RNA‐induced silencing complex (RISC), with target p21 mRNA via binding of the stem‐loop structure near the microRNA (miRNA) target site. Depletion of Wig1 prohibited miRNA‐mediated p21 mRNA decay and resulted in premature senescence. Wig1 plays an essential role in cell proliferation, as demonstrated in tumour xenografts in mice, and Wig1 and p21 mRNA levels are inversely correlated in human normal and cancer tissues. Together, our data indicate a novel role of Wig1 in RISC target accessibility, which is a key step in RNA‐mediated gene silencing. In addition, these findings indicate that fine‐tuning of p21 levels by Wig1 is essential for the prevention of cellular senescence. 相似文献
993.
Wang JL Lin KL Chen WC Chou CT Huang CJ Liu CS Hsieh CH Chang CH Huang JK Chang HT Liu SI Hsu SS Jan CR 《Journal of receptor and signal transduction research》2005,25(4-6):237-249
The effect of celecoxib on renal tubular cells is largely unexplored. In Madin Darby canine kidney (MDCK) cells, the effect of celecoxib on intracellular CaCa2+ concentration ([Ca2+]i) and proliferation was examined by using the Ca(2 +)-sensitive fluorescent dye fura-2 and the viability detecting fluorescent dye tetrazolium, respectively. Celecoxib (> or =1 micro M) caused an increase of [CaCa2+]i in a concentration-dependent manner. Celecoxib-induced [CaCa2+]i increase was partly reduced by removal of extracellular CaCa2+. Celecoxib-induced CaCa2+ influx was independently suggested by MnCa2+ influx-induced fura-2 fluorescence quench. In Ca(2 +)-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca(2 +)-ATPase, caused a monophasic [CaCa2+]i increase, after which celecoxib only induced a tiny [CaCa2+]i increase; conversely, pretreatment with celecoxib completely inhibited thapsigargin-induced [CaCa2+]i increases. U73122, an inhibitor of phospholipase C, abolished ATP (but not celecoxib)-induced [CaCa2+]i increases. Overnight incubation with 1 or 10 micro M celecoxib decreased cell viability by 80% and 100%, respectively. These data indicate that celecoxib evokes a [CaCa2+]i increase in renal tubular cells by stimulating both extracellular CaCa2+ influx and intracellular CaCa2+ release and is highly toxic to renal tubular cells in vitro. 相似文献
994.
Li Ni‐Komatsu Jennifer K. Leung Darren Williams Jaeki Min Sonya M. Khersonsky Young‐Tae Chang Seth J. Orlow 《Pigment cell & melanoma research》2005,18(6):447-453
As most of the available depigmenting agents exhibit only modest activity and some exhibit toxicities that lead to adverse side effects after long‐term usage, there remains a need for novel depigmenting agents. Chemical genetic screening was performed on cultured melanocytes to identify novel depigmenting compounds. By screening a tagged‐triazine library, we identified four compounds, TGH11, TGD10, TGD39 and TGJ29, as potent pigmentation inhibitors with IC50 values in the range of 10 μM. These newly identified depigmenting compounds were found to function as reversible inhibitors of tyrosinase, the key enzyme involved in melanin synthesis. Tyrosinase was further confirmed as the cellular target of these compounds by affinity chromatography. Kinetic data suggest that all four compounds act as competitive inhibitors of tyrosinase, most likely competing with l ‐3,4‐dihydroxyphenylalanine (l ‐DOPA) for binding to the DOPA‐binding site of the enzyme. No effect on levels of tyrosinase protein, processing or trafficking was observed upon treatment of melanocytes with these compounds. Cytotoxicity was not observed with these compounds at concentrations up to 20 μM. Our data suggest that TGH11, TGD10, TGD39 and TGJ29 are novel potent tyrosinase inhibitors with potential beneficial effects in the treatment of cutaneous hyperpigmentation. 相似文献
995.
996.
Zhang D Mott JL Chang SW Stevens M Mikolajczak P Zassenhaus HP 《American journal of physiology. Heart and circulatory physiology》2005,288(5):H2476-H2483
Increased frequencies of mitochondrial DNA (mtDNA) mutations characterize the aging heart and are also found in idiopathic dilated cardiomyopathy and end-stage heart failure. The pathogenic potential of such mutations is unclear. Transgenic mice showing accelerated accumulation of mtDNA mutations and dilated cardiomyopathy due to expression of an error-prone mtDNA polymerase specifically in the heart were characterized by Western blot analysis and immunohistochemistry for the levels of pro- and antiapoptotic proteins. By 8 wk of age, when frequencies of mtDNA mutations were approximately 0.01% and all transgenic mice showed four-chamber cardiac dilation, a vigorous prosurvival response was evident. Upregulated were Bcl-2, Bcl-xl, Bfl1, heat shock protein 27, and X-linked inhibitor of apoptosis protein, all of which function to inhibit apoptosis. Although translocation of Bax to mitochondria was also seen, it was not integrated into the mitochondrial membrane. Treatment of transgenic mice with doxorubicin failed to induce apoptosis, in contrast to controls, showing that the prosurvival response protected cardiomyocytes from a death stimulus. Increased apoptosis and release of cytochrome c appeared to precede the establishment of the prosurvival state suggesting that it may reflect a response to activation of programmed cell death pathways. It has been proposed that a programmed cell survival response is activated in the failing and aging heart. We show that elevated frequencies of mtDNA mutations may serve as one trigger for the activation of such a response. 相似文献
997.
AB Chang NC Cox J Purcell JM Marchant PJ Lewindon GJ Cleghorn LC Ee GD Withers MK Patrick J Faoagali 《Respiratory research》2005,6(1):1-5
Background and methods
Human metapneumovirus (hMPV) is a recently discovered respiratory virus associated with bronchiolitis, pneumonia, croup and exacerbations of asthma. Since respiratory viruses are frequently detected in patients with acute exacerbations of COPD (AE-COPD) it was our aim to investigate the frequency of hMPV detection in a prospective cohort of hospitalized patients with AE-COPD compared to patients with stable COPD and to smokers without by means of quantitative real-time RT-PCR.Results
We analysed nasal lavage and induced sputum of 130 patients with AE-COPD, 65 patients with stable COPD and 34 smokers without COPD. HMPV was detected in 3/130 (2.3%) AE-COPD patients with a mean of 6.5 × 105 viral copies/ml in nasal lavage and 1.88 × 105 viral copies/ml in induced sputum. It was not found in patients with stable COPD or smokers without COPD.Conclusion
HMPV is only found in a very small number of patients with AE-COPD. However it should be considered as a further possible viral trigger of AE-COPD because asymptomatic carriage is unlikely. 相似文献998.
999.
Ho Nam Chang Nag-Jong Kim Jongwon Kang Chang Moon Jeong 《Biotechnology and Bioprocess Engineering》2010,15(1):1-10
The typical biorefinery platforms are sugar, thermochemical (syngas), carbon-rich chains, and biogas platforms, each offering
unique advantages and disadvantages. The sugar platform uses hexose and pentose sugars extracted or converted from plant body
mass. The thermochemical (syngas) platform entails a chemical or biological conversion process using pyrolysis or gasification
of plants to produce biofuels. The carbon-rich chains platform is used to produce biodiesel from long-chain fatty acids or
glycerides. In the present work, we suggest a new platform using volatile fatty acids (VFAs) for the production of biofuels
and biochemicals production. The VFAs are short-chain fatty acids composed mainly of acetate and butyrate in the anaerobic
digestion (AD) process, which does not need sterilization, additional hydrolysis enzymes (cellulose or xylanase), or a high
cost pretreatment step. VFAs are easily produced from almost all kinds of biomass with low lignin content (terrestrial, aquatic,
and marine biomass) by the AD process. Considering that raw material alone constitutes 40∼80% of biofuel production costs,
biofuels made from VFAs derived from waste organic biomass potentially offer significant economical advantage. 相似文献
1000.
Fuhai Li Xiaobo Zhou Wanting Huang Chung-Che Chang Stephen TC Wong 《BMC bioinformatics》2010,11(1):200