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951.
Soscia SJ Tong M Xu XJ Cohen AC Chu J Wands JR de la Monte SM 《Cellular and molecular life sciences : CMLS》2006,63(17):2039-2056
In fetal alcohol syndrome (FAS), cerebellar hypoplasia is associated with impaired insulin-stimulated survival signaling.
This study characterizes ethanol dose-effects on cerebellar development, expression of genes required for insulin and insulin-like
growth factor (IGF) signaling, and the upstream mechanisms and downstream consequences of impaired signaling in relation to
acetylcholine (ACh) homeostasis. Pregnant Long Evans rats were fed isocaloric liquid diets containing 0%, 2%, 4.5%, 6.5%,
or 9.25% ethanol from gestation day 6. Ethanol caused dose-dependent increases in severity of cerebellar hypoplasia, neuronal
loss, proliferation of astrocytes and microglia, and DNA damage. Ethanol also reduced insulin, IGF-I, and IGF-II receptor
binding, insulin and IGF-I receptor tyrosine kinase activities, ATP, membrane cholesterol, and choline acetyltransferase (ChAT)
expression. In vitro studies linked membrane cholesterol depletion to impaired insulin receptor binding and insulin-stimulated ChAT. In conclusion,
cerebellar hypoplasia in FAS is mediated by insulin/IGF resistance with attendant impairments in energy production and ACh
homeostasis.
Received 4 May 2006; received after revision 13 June 2006; accepted 20 June 2006 相似文献
952.
设计并实现了一个基于WSRF的网格计算平台, 该系统基
于Globus Toolkit 4, 集成了元调度器CSF4, 本地调度器SGE5.3/6.0, LSF6.0和openPBS2.3
.16以及数据网格系统Gfarm. 在功能上, 该系统可协同本地及远程的资源管理器, 支持WS
GRAM和Pre WS GRAM(GT2 Gatekeeper)的协作, 支持完全地委托用户代理证书; 在任
务管理上, 该系统提供了排队服务, 并支持定制调度策略; 另外, 该系统支持LSF, PBS,
SGE, Condor等多种资源管理器类型. 相似文献
953.
Like many virtuosi in his day, the English philosopher John Locke maintained an active interest in metrology. Yet for Locke, this was no mere hobby: questions concerning measurement were also implicated in his ongoing philosophical project to develop an account of human understanding. This paper follows Locke's treatment of four problems of measurement from the early Drafts A and B of the Essay concerning Human Understanding to the publication of this famous book and its aftermath. It traces Locke's attempt to develop a natural or universal standard for the measure of length, his attempts to grapple with the measurement of duration, as well as the problems of determining comparative measures for secondary qualities, and the problem of discriminating small differences in the conventional measures of his day. It is argued that the salient context for Locke's treatment of these problems is the new experimental philosophy and its method of experimental natural history. 相似文献
954.
Numerous studies attest to essential roles for Eph receptors and their ephrin ligands in controlling cell positioning and tissue patterning during normal and oncogenic development. These studies suggest multiple, sometimes contradictory, functions of Eph-ephrin signalling, which under different conditions can promote either spreading and cell-cell adhesion or cytoskeletal collapse, cell rounding, de-adhesion and cell-cell segregation. A principle determinant of the balance between these two opposing responses is the degree of receptor/ligand clustering and activation. This equilibrium is likely altered in cancers and modulated by somatic mutations of key Eph family members that have emerged as candidate cancer markers in recent profiling studies. In addition, cross-talk amongst Ephs and with other signalling pathways significantly modulates cell-cell adhesion, both between and within Eph- and ephrin-expressing cell populations. This review summarises our current understanding of how Eph receptors control cell adhesion and morphology, and presents examples demonstrating the importance of these events in normal development and cancer. 相似文献
955.
Fairfax BP Makino S Radhakrishnan J Plant K Leslie S Dilthey A Ellis P Langford C Vannberg FO Knight JC 《Nature genetics》2012,44(5):502-510
Trans-acting genetic variants have a substantial, albeit poorly characterized, role in the heritable determination of gene expression. Using paired purified primary monocytes and B cells, we identify new predominantly cell type-specific cis and trans expression quantitative trait loci (eQTLs), including multi-locus trans associations to LYZ and KLF4 in monocytes and B cells, respectively. Additionally, we observe a B cell-specific trans association of rs11171739 at 12q13.2, a known autoimmune disease locus, with IP6K2 (P = 5.8 × 10(-15)), PRIC285 (P = 3.0 × 10(-10)) and an upstream region of CDKN1A (P = 2 × 10(-52)), suggesting roles for cell cycle regulation and peroxisome proliferator-activated receptor γ (PPARγ) signaling in autoimmune pathogenesis. We also find that specific human leukocyte antigen (HLA) alleles form trans associations with the expression of AOAH and ARHGAP24 in monocytes but not in B cells. In summary, we show that mapping gene expression in defined primary cell populations identifies new cell type-specific trans-regulated networks and provides insights into the genetic basis of disease susceptibility. 相似文献
956.
KU Ludwig E Mangold S Herms S Nowak H Reutter A Paul J Becker R Herberz T Alchawa E Nasser AC Böhmer M Mattheisen MA Alblas S Barth N Kluck C Lauster B Braumann RH Reich A Hemprich S Pötzsch B Blaumeiser N Daratsianos T Kreusch JC Murray ML Marazita I Ruczinski AF Scott TH Beaty FJ Kramer TF Wienker RP Steegers-Theunissen M Rubini PA Mossey P Hoffmann C Lange S Cichon P Propping M Knapp MM Nöthen 《Nature genetics》2012,44(9):968-971
We have conducted the first meta-analyses for nonsyndromic cleft lip with or without cleft palate (NSCL/P) using data from the two largest genome-wide association studies published to date. We confirmed associations with all previously identified loci and identified six additional susceptibility regions (1p36, 2p21, 3p11.1, 8q21.3, 13q31.1 and 15q22). Analysis of phenotypic variability identified the first specific genetic risk factor for NSCLP (nonsyndromic cleft lip plus palate) (rs8001641; P(NSCLP) = 6.51 × 10(-11); homozygote relative risk = 2.41, 95% confidence interval (CI) 1.84-3.16). 相似文献
957.
Iness Charfi Karim Nagi Ouissame Mnie-Filali Dominic Thibault Gianfranco Balboni Peter W. Schiller Louis-Eric Trudeau Graciela Pineyro 《Cellular and molecular life sciences : CMLS》2014,71(8):1529-1546
Signaling bias refers to G protein-coupled receptor ligand ability to preferentially activate one type of signal over another. Bias to evoke signaling as opposed to sequestration has been proposed as a predictor of opioid ligand potential for generating tolerance. Here we measured whether delta opioid receptor agonists preferentially inhibited cyclase activity over internalization in HEK cells. Efficacy (τ) and affinity (KA) values were estimated from functional data and bias was calculated from efficiency coefficients (log τ/KA). This approach better represented the data as compared to alternative methods that estimate bias exclusively from τ values. Log (τ/KA) coefficients indicated that SNC-80 and UFP-512 promoted cyclase inhibition more efficiently than DOR internalization as compared to DPDPE (bias factor for SNC-80: 50 and for UFP-512: 132). Molecular determinants of internalization were different in HEK293 cells and neurons with βarrs contributing to internalization in both cell types, while PKC and GRK2 activities were only involved in neurons. Rank orders of ligand ability to engage different internalization mechanisms in neurons were compared to rank order of E max values for cyclase assays in HEK cells. Comparison revealed a significant reversal in rank order for cyclase E max values and βarr-dependent internalization in neurons, indicating that these responses were ligand-specific. Despite this evidence, and because kinases involved in internalization were not the same across cellular backgrounds, it is not possible to assert if the magnitude and nature of bias revealed by rank orders of maximal responses is the same as the one measured in HEK cells. 相似文献
958.
Eoin P. Cummins Andrew C. Selfridge Peter H. Sporn Jacob I. Sznajder Cormac T. Taylor 《Cellular and molecular life sciences : CMLS》2014,71(5):831-845
The capacity of organisms to sense changes in the levels of internal and external gases and to respond accordingly is central to a range of physiologic and pathophysiologic processes. Carbon dioxide, a primary product of oxidative metabolism is one such gas that can be sensed by both prokaryotic and eukaryotic cells and in response to altered levels, elicit the activation of multiple adaptive pathways. The outcomes of activating CO2-sensitive pathways in various species include increased virulence of fungal and bacterial pathogens, prey-seeking behavior in insects as well as taste perception, lung function, and the control of immunity in mammals. In this review, we discuss what is known about the mechanisms underpinning CO2 sensing across a range of species and consider the implications of this for physiology, disease progression, and the possibility of developing new therapeutics for inflammatory and infectious disease. 相似文献
959.
Weedon MN Lango H Lindgren CM Wallace C Evans DM Mangino M Freathy RM Perry JR Stevens S Hall AS Samani NJ Shields B Prokopenko I Farrall M Dominiczak A;Diabetes Genetics Initiative;Wellcome Trust Case Control Consortium Johnson T Bergmann S Beckmann JS Vollenweider P Waterworth DM Mooser V Palmer CN Morris AD Ouwehand WH;Cambridge GEM Consortium Zhao JH Li S Loos RJ Barroso I Deloukas P Sandhu MS Wheeler E Soranzo N Inouye M Wareham NJ Caulfield M Munroe PB Hattersley AT McCarthy MI Frayling TM 《Nature genetics》2008,40(5):575-583
Adult height is a model polygenic trait, but there has been limited success in identifying the genes underlying its normal variation. To identify genetic variants influencing adult human height, we used genome-wide association data from 13,665 individuals and genotyped 39 variants in an additional 16,482 samples. We identified 20 variants associated with adult height (P < 5 x 10(-7), with 10 reaching P < 1 x 10(-10)). Combined, the 20 SNPs explain approximately 3% of height variation, with a approximately 5 cm difference between the 6.2% of people with 17 or fewer 'tall' alleles compared to the 5.5% with 27 or more 'tall' alleles. The loci we identified implicate genes in Hedgehog signaling (IHH, HHIP, PTCH1), extracellular matrix (EFEMP1, ADAMTSL3, ACAN) and cancer (CDK6, HMGA2, DLEU7) pathways, and provide new insights into human growth and developmental processes. Finally, our results provide insights into the genetic architecture of a classic quantitative trait. 相似文献
960.
Jaeger E Webb E Howarth K Carvajal-Carmona L Rowan A Broderick P Walther A Spain S Pittman A Kemp Z Sullivan K Heinimann K Lubbe S Domingo E Barclay E Martin L Gorman M Chandler I Vijayakrishnan J Wood W Papaemmanuil E Penegar S Qureshi M;CORGI Consortium Farrington S Tenesa A Cazier JB Kerr D Gray R Peto J Dunlop M Campbell H Thomas H Houlston R Tomlinson I 《Nature genetics》2008,40(1):26-28
We mapped a high-penetrance gene (CRAC1; also known as HMPS) associated with colorectal cancer (CRC) in the Ashkenazi population to a 0.6-Mb region on chromosome 15 containing SCG5 (also known as SGNE1), GREM1 and FMN1. We hypothesized that the CRAC1 locus harbored low-penetrance variants that increased CRC risk in the general population. In a large series of colorectal cancer cases and controls, SNPs near GREM1 and SCG5 were strongly associated with increased CRC risk (for rs4779584, P = 4.44 x 10(-14)). 相似文献