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231.
Farima Zahedi Maliheh Nazari-Jahantigh Zhe Zhou Pallavi Subramanian Yuanyuan Wei Jochen Grommes Stefan Offermanns Sabine Steffens Christian Weber Andreas Schober 《Cellular and molecular life sciences : CMLS》2017,74(2):359-372
MicroRNAs (miRNAs) coordinate vascular repair by regulating injury-induced gene expression in vascular smooth muscle cells (SMCs) and promote the transition of SMCs from a contractile to a proliferating phenotype. However, the effect of miRNA expression in SMCs on neointima formation is unclear. Therefore, we studied the role of miRNA biogenesis by Dicer in SMCs in vascular repair. Following wire-induced injury to carotid arteries of Apolipoprotein E knockout (Apoe ?/?) mice, miRNA microarray analysis revealed that the most significantly regulated miRNAs, such as miR-222 and miR-21-3p, were upregulated. Conditional deletion of Dicer in SMCs increased neointima formation by reducing SMC proliferation in Apoe ?/? mice, and decreased mainly the expression of miRNAs, such as miR-147 and miR-100, which were not upregulated following vascular injury. SMC-specific deletion of Dicer promoted growth factor and inflammatory signaling and regulated a miRNA–target interaction network in injured arteries that was enriched in anti-proliferative miRNAs. The most connected miRNA in this network was miR-27a-3p [e.g., with Rho guanine nucleotide exchange factor 26 (ARHGEF26)], which was expressed in medial and neointimal SMCs in a Dicer-dependent manner. In vitro, miR-27a-3p suppresses ARHGEF26 expression and inhibits SMC proliferation by interacting with a conserved binding site in the 3′ untranslated region of ARHGEF26 mRNA. We propose that Dicer expression in SMCs plays an essential role in vascular repair by generating anti-proliferative miRNAs, such as miR-27a-3p, to prevent vessel stenosis due to exaggerated neointima formation. 相似文献
232.
Radbruch A 《Cellular and molecular life sciences : CMLS》2012,69(10):1563-1564
233.
Merkel cell carcinoma (MCC) is a highly aggressive neuroendocrine carcinoma of the skin. More than one-third of MCC patients
will die from this cancer, making it twice as lethal as malignant melanoma. Despite the fact that MCC is still a very rare
tumor, its incidence is rapidly increasing; the American Cancer Society estimates for 2008 almost 1 500 new cases in the USA.
These clinical observations are especially disturbing as the pathogenesis of MCC is not yet fully understood; however, a number
of recent reports contribute to a better understanding of its pathogenesis. Here we describe findings regarding the role of
Wnt, MAPK and Akt signaling as well as possible aberrations in the p14ARF/p53/RB tumor suppressor network in MCC. Most important,
and possibly with high impact on future therapeutic approaches is the demonstration that a polyomavirus has frequently integrated
in the genome of the MCC cells prior to tumor development.
Received 12 August 2008; received after revision 06 October 2008; accepted 22 October 2008 相似文献
234.
Cízková A Stránecký V Mayr JA Tesarová M Havlícková V Paul J Ivánek R Kuss AW Hansíková H Kaplanová V Vrbacký M Hartmannová H Nosková L Honzík T Drahota Z Magner M Hejzlarová K Sperl W Zeman J Houstek J Kmoch S 《Nature genetics》2008,40(11):1288-1290
We carried out whole-genome homozygosity mapping, gene expression analysis and DNA sequencing in individuals with isolated mitochondrial ATP synthase deficiency and identified disease-causing mutations in TMEM70. Complementation of the cell lines of these individuals with wild-type TMEM70 restored biogenesis and metabolic function of the enzyme complex. Our results show that TMEM70 is involved in mitochondrial ATP synthase biogenesis in higher eukaryotes. 相似文献
235.
A genome-wide association scan of nonsynonymous SNPs identifies a susceptibility variant for Crohn disease in ATG16L1 总被引:16,自引:0,他引:16
Hampe J Franke A Rosenstiel P Till A Teuber M Huse K Albrecht M Mayr G De La Vega FM Briggs J Günther S Prescott NJ Onnie CM Häsler R Sipos B Fölsch UR Lengauer T Platzer M Mathew CG Krawczak M Schreiber S 《Nature genetics》2007,39(2):207-211
We performed a genome-wide association study of 19,779 nonsynonymous SNPs in 735 individuals with Crohn disease and 368 controls. A total of 7,159 of these SNPs were informative. We followed up on all 72 SNPs with P 0.4), these data suggest that the underlying biological process may be specific to Crohn disease. 相似文献
236.
Sandilands A Terron-Kwiatkowski A Hull PR O'Regan GM Clayton TH Watson RM Carrick T Evans AT Liao H Zhao Y Campbell LE Schmuth M Gruber R Janecke AR Elias PM van Steensel MA Nagtzaam I van Geel M Steijlen PM Munro CS Bradley DG Palmer CN Smith FJ McLean WH Irvine AD 《Nature genetics》2007,39(5):650-654
We recently reported two common filaggrin (FLG) null mutations that cause ichthyosis vulgaris and predispose to eczema and secondary allergic diseases. We show here that these common European mutations are ancestral variants carried on conserved haplotypes. To facilitate comprehensive analysis of other populations, we report a strategy for full sequencing of this large, highly repetitive gene, and we describe 15 variants, including seven that are prevalent. All the variants are either nonsense or frameshift mutations that, in representative cases, resulted in loss of filaggrin production in the epidermis. In an Irish case-control study, the five most common European mutations showed a strong association with moderate-to-severe childhood eczema (chi2 test: P = 2.12 x 10(-51); Fisher's exact test: heterozygote odds ratio (OR) = 7.44 (95% confidence interval (c.i.) = 4.9-11.3), and homozygote OR = 151 (95% c.i. = 20-1,136)). We found three additional rare null mutations in this case series, suggesting that the genetic architecture of filaggrin-related atopic dermatitis consists of both prevalent and rare risk alleles. 相似文献
237.
Chia Chun Lo Konstantinos Skindilias Andreas Karathanasopoulos 《Journal of forecasting》2016,35(1):54-69
We propose a new methodology for filtering and forecasting the latent variance in a two‐factor diffusion process with jumps from a continuous‐time perspective. For this purpose we use a continuous‐time Markov chain approximation with a finite state space. Essentially, we extend Markov chain filters to processes of higher dimensions. We assess forecastability of the models under consideration by measuring forecast error of model expected realized variance, trading in variance swap contracts, producing value‐at‐risk estimates as well as examining sign forecastability. We provide empirical evidence using two sources, the S&P 500 index values and its corresponding cumulative risk‐neutral expected variance (namely the VIX index). Joint estimation reveals the market prices of equity and variance risk implicit by the two probability measures. A further simulation study shows that the proposed methodology can filter the variance of virtually any type of diffusion process (coupled with a jump process) with a non‐analytical density function. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
238.
Hori M Sótér A Barna D Dax A Hayano R Friedreich S Juhász B Pask T Widmann E Horváth D Venturelli L Zurlo N 《Nature》2011,475(7357):484-488
Physical laws are believed to be invariant under the combined transformations of charge, parity and time reversal (CPT symmetry). This implies that an antimatter particle has exactly the same mass and absolute value of charge as its particle counterpart. Metastable antiprotonic helium (pHe(+)) is a three-body atom consisting of a normal helium nucleus, an electron in its ground state and an antiproton (p) occupying a Rydberg state with high principal and angular momentum quantum numbers, respectively n and l, such that n?≈?l?+?1?≈?38. These atoms are amenable to precision laser spectroscopy, the results of which can in principle be used to determine the antiproton-to-electron mass ratio and to constrain the equality between the antiproton and proton charges and masses. Here we report two-photon spectroscopy of antiprotonic helium, in which p(3)He(+) and p(4)He(+) isotopes are irradiated by two counter-propagating laser beams. This excites nonlinear, two-photon transitions of the antiproton of the type (n, l)?→?(n?-?2, l?-?2) at deep-ultraviolet wavelengths (λ = 139.8, 193.0 and 197.0?nm), which partly cancel the Doppler broadening of the laser resonance caused by the thermal motion of the atoms. The resulting narrow spectral lines allowed us to measure three transition frequencies with fractional precisions of 2.3-5 parts in 10(9). By comparing the results with three-body quantum electrodynamics calculations, we derived an antiproton-to-electron mass ratio of 1,836.1526736(23), where the parenthetical error represents one standard deviation. This agrees with the proton-to-electron value known to a similar precision. 相似文献
239.
Spyros Makridakis Andreas Merikas Anna Merika Mike G. Tsionas Marwan Izzeldin 《Journal of forecasting》2020,39(1):56-68
Marine transport has grown rapidly as the result of globalization and sustainable world growth rates. Shipping market risks and uncertainty have also grown and need to be mitigated with the development of a more reliable procedure to predict changes in freight rates. In this paper, we propose a new forecasting model and apply it to the Baltic Dry Index (BDI). Such a model compresses, in an optimal way, information from the past in order to predict freight rates. To develop the forecasting model, we deploy a basic set of predictors, add lags of the BDI and introduce additional variables, in applying Bayesian compressed regression (BCR), with two important innovations. First, we include transition functions in the predictive set to capture both smooth and abrupt changes in the time path of BDI; second, we do not estimate the parameters of the transition functions, but rather embed them in the random search procedure inherent in BCR. This allows all coefficients to evolve in a time-varying manner, while searching for the best predictors within the historical set of data. The new procedures predict the BDI with considerable success. 相似文献
240.
Yujing Gong Kung‐Cheng Ho Chia‐Chun Lo Andreas Karathanasopoulos I‐Ming Jiang 《Journal of forecasting》2019,38(4):354-373
This paper investigates the role of corporate social responsibility (CSR) performance in forecasting companys' stock prices and future returns. The forecasting analysis identifies a negative association between CSR performance and proxies of price delay. The negative CSR–delay association is weak for state‐owned enterprises (SOEs) because of their politically oriented motivation of CSR activities, but significantly strong for non‐SOEs. Furthermore, we find that forecasting delayed firms is expected to have higher future returns. In particular, the returns premium is most attributable to the CSR component of delay, compared with the non‐CSR component. Taken together, these results suggest that CSR performance plays a positive role in enhancing stock price efficiency, and a potential explanation is that CSR performance can be considered as additional information for equity predictions. 相似文献