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971.
Tiziana Bascelli Piotr Błaszczyk Alexandre Borovik Vladimir Kanovei Karin U. Katz Mikhail G. Katz Semen S. Kutateladze Thomas McGaffey David M. Schaps David Sherry 《Foundations of Science》2018,23(2):267-296
Cauchy's sum theorem is a prototype of what is today a basic result on the convergence of a series of functions in undergraduate analysis. We seek to interpret Cauchy’s proof, and discuss the related epistemological questions involved in comparing distinct interpretive paradigms. Cauchy’s proof is often interpreted in the modern framework of a Weierstrassian paradigm. We analyze Cauchy’s proof closely and show that it finds closer proxies in a different modern framework. 相似文献
972.
A new species of Pseudolepturges from Bolivia is described and illustrated; a key to the species is also provided. Based on the similar body size, orange-yellowish colour, behaviour, and close co-occurrence on a Triplaris americana tree, we suggest that Pseudolepturges triplarinus sp. nov. is a mimic of the ant Pseudomyrmex triplarinus.
http://www.zoobank.org/urn:lsid:zoobank.org:pub:6DF38C64-6986-4A79-8D9A-645DA89149F2 相似文献
973.
Henriikka Kentala Annika Koponen Helena Vihinen Juho Pirhonen Gerhard Liebisch Zoltan Pataj Annukka Kivelä Shiqian Li Leena Karhinen Eeva Jääskeläinen Robert Andrews Leena Meriläinen Silke Matysik Elina Ikonen You Zhou Eija Jokitalo Vesa M. Olkkonen 《Cellular and molecular life sciences : CMLS》2018,75(21):4041-4057
ORP2 is a ubiquitously expressed OSBP-related protein previously implicated in endoplasmic reticulum (ER)—lipid droplet (LD) contacts, triacylglycerol (TG) metabolism, cholesterol transport, adrenocortical steroidogenesis, and actin-dependent cell dynamics. Here, we characterize the role of ORP2 in carbohydrate and lipid metabolism by employing ORP2-knockout (KO) hepatoma cells (HuH7) generated by CRISPR-Cas9 gene editing. The ORP2-KO and control HuH7 cells were subjected to RNA sequencing, analyses of Akt signaling, carbohydrate and TG metabolism, the extracellular acidification rate, and the lipidome, as well as to transmission electron microscopy. The loss of ORP2 resulted in a marked reduction of active phosphorylated Akt(Ser473) and its target Glycogen synthase kinase 3β(Ser9), consistent with defective Akt signaling. ORP2 was found to form a physical complex with the key controllers of Akt activity, Cdc37, and Hsp90, and to co-localize with Cdc37 and active Akt(Ser473) at lamellipodial plasma membrane regions, in addition to the previously reported ER–LD localization. ORP2-KO reduced glucose uptake, glycogen synthesis, glycolysis, mRNA-encoding glycolytic enzymes, and SREBP-1 target gene expression, and led to defective TG synthesis and storage. ORP2-KO did not reduce but rather increased ER–LD contacts under basal culture conditions and interfered with their expansion upon fatty acid loading. Together with our recently published work (Kentala et al. in FASEB J 32:1281–1295, 2018), this study identifies ORP2 as a new regulatory nexus of Akt signaling, cellular energy metabolism, actin cytoskeletal function, cell migration, and proliferation. 相似文献
974.
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
975.
Di Bernardo MC Crowther-Swanepoel D Broderick P Webb E Sellick G Wild R Sullivan K Vijayakrishnan J Wang Y Pittman AM Sunter NJ Hall AG Dyer MJ Matutes E Dearden C Mainou-Fowler T Jackson GH Summerfield G Harris RJ Pettitt AR Hillmen P Allsup DJ Bailey JR Pratt G Pepper C Fegan C Allan JM Catovsky D Houlston RS 《Nature genetics》2008,40(10):1204-1210
We conducted a genome-wide association study of 299,983 tagging SNPs for chronic lymphocytic leukemia (CLL) and performed validation in two additional series totaling 1,529 cases and 3,115 controls. We identified six previously unreported CLL risk loci at 2q13 (rs17483466; P = 2.36 x 10(-10)), 2q37.1 (rs13397985, SP140; P = 5.40 x 10(-10)), 6p25.3 (rs872071, IRF4; P = 1.91 x 10(-20)), 11q24.1 (rs735665; P = 3.78 x 10(-12)), 15q23 (rs7176508; P = 4.54 x 10(-12)) and 19q13.32 (rs11083846, PRKD2; P = 3.96 x 10(-9)). These data provide the first evidence for the existence of common, low-penetrance susceptibility to a hematological malignancy and new insights into disease causation in CLL. 相似文献
976.
Katajisto P Vaahtomeri K Ekman N Ventelä E Ristimäki A Bardeesy N Feil R DePinho RA Mäkelä TP 《Nature genetics》2008,40(4):455-459
Germline mutations in STK11 (also known as LKB1) are found in individuals with Peutz-Jeghers syndrome (PJS) manifesting with gastrointestinal polyps that contain a prominent stromal component. Epithelia in polyps of Stk11(+/-) mice can retain a functional copy of Stk11 (refs. 2,3), and loss of heterozygosity is not an obligate feature of human polyps, raising the possibility of non-epithelial origins in tumorigenesis. Here we show that either monoallelic or biallelic loss of murine Stk11 limited to Tagln-expressing mesenchymal cells results in premature postnatal death as a result of gastrointestinal polyps indistinguishable from those in PJS. Stk11-deficient mesenchymal cells produced less TGFbeta, and defective TGFbeta signaling to epithelial cells coincided with epithelial proliferation. We also noted TGFbeta signaling defects in polyps of individuals with PJS, suggesting that the identified stromal-derived mechanism of tumor suppression is also relevant in PJS. 相似文献
977.
International Consortium for Systemic Lupus Erythematosus Genetics 《Nature genetics》2008,40(2):204-210
Systemic lupus erythematosus (SLE) is a common systemic autoimmune disease with complex etiology but strong clustering in families (lambda(S) = approximately 30). We performed a genome-wide association scan using 317,501 SNPs in 720 women of European ancestry with SLE and in 2,337 controls, and we genotyped consistently associated SNPs in two additional independent sample sets totaling 1,846 affected women and 1,825 controls. Aside from the expected strong association between SLE and the HLA region on chromosome 6p21 and the previously confirmed non-HLA locus IRF5 on chromosome 7q32, we found evidence of association with replication (1.1 x 10(-7) < P(overall) < 1.6 x 10(-23); odds ratio = 0.82-1.62) in four regions: 16p11.2 (ITGAM), 11p15.5 (KIAA1542), 3p14.3 (PXK) and 1q25.1 (rs10798269). We also found evidence for association (P < 1 x 10(-5)) at FCGR2A, PTPN22 and STAT4, regions previously associated with SLE and other autoimmune diseases, as well as at > or =9 other loci (P < 2 x 10(-7)). Our results show that numerous genes, some with known immune-related functions, predispose to SLE. 相似文献
978.
Nath SK Han S Kim-Howard X Kelly JA Viswanathan P Gilkeson GS Chen W Zhu C McEver RP Kimberly RP Alarcón-Riquelme ME Vyse TJ Li QZ Wakeland EK Merrill JT James JA Kaufman KM Guthridge JM Harley JB 《Nature genetics》2008,40(2):152-154
We identified and replicated an association between ITGAM (CD11b) at 16p11.2 and risk of systemic lupus erythematosus (SLE) in 3,818 individuals of European descent. The strongest association was at a nonsynonymous SNP, rs1143679 (P = 1.7 x 10(-17), odds ratio = 1.78). We further replicated this association in two independent samples of individuals of African descent (P = 0.0002 and 0.003; overall meta-analysis P = 6.9 x 10(-22)). The genetic association between ITGAM and SLE implicates the alpha(M)beta2-integrin adhesion pathway in disease development. 相似文献
979.
Core formation by gravitational segregation allegedly released sufficient interior heat to melt the Earth. Analysis of the energetics, which compare gravitational potential energy (Ug) of a fictitious,... 相似文献
980.
Robert E. Criss 《地球科学学刊》2015,(1)
Fluid-rock interactions alter the geochemical, isotopic, petrographic and physical character of host rocks, producing a permanent record of hydrothermal activity. Maps of altered rock properties show r... 相似文献