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41.
Paul Little  Li Hsu  Wei Sun 《Biometrics》2023,79(3):2705-2718
Somatic mutations in cancer patients are inherently sparse and potentially high dimensional. Cancer patients may share the same set of deregulated biological processes perturbed by different sets of somatically mutated genes. Therefore, when assessing the associations between somatic mutations and clinical outcomes, gene-by-gene analysis is often under-powered because it does not capture the complex disease mechanisms shared across cancer patients. Rather than testing genes one by one, an intuitive approach is to aggregate somatic mutation data of multiple genes to assess their joint association with clinical outcomes. The challenge is how to aggregate such information. Building on the optimal transport method, we propose a principled approach to estimate the similarity of somatic mutation profiles of multiple genes between tumor samples, while accounting for gene–gene similarities defined by gene annotations or empirical mutational patterns. Using such similarities, we can assess the associations between somatic mutations and clinical outcomes by kernel regression. We have applied our method to analyze somatic mutation data of 17 cancer types and identified at least five cancer types, where somatic mutations are associated with overall survival, progression-free interval, or cytolytic activity.  相似文献   
42.
Chromosomal localization of uroplakin genes of cattle and mice   总被引:2,自引:0,他引:2  
The asymmetric unit membrane (AUM) of the apical surface of mammalian urinary bladder epithelium contains several major integral membrane proteins, including uroplakins IA and IB (both 27 kDa), II (15 kDa), and III (47 kDa). These proteins are synthesized only in terminally differentiated bladder epithelial cells. They are encoded by separate genes and, except for uroplakins IA and IB, appear to be unrelated in their amino acid sequences. The genes encoding these uroplakins were mapped to chromosomes of cattle through their segregation in a panel of bovine x rodent somatic cell hybrids. Genes for uroplakins IA, IB, and II were mapped to bovine (BTA) Chromosomes (Chrs) 18 (UPK1A), 1 (UPK1B), and 15 (UPK2), respectively. Two bovine genomic DNA sequences reactive with a uroplakin III cDNA probe were identified and mapped to BTA 6 (UPK3A) and 5 (UPK3B). We have also mapped genes for uroplakins 1A and II in mice, to the proximal regions of mouse Chr 7 (Upk1a) and 9 (Upk2), respectively, by analyzing the inheritance of restriction fragment length variants in recombinant inbred mouse strains. These assignments are consistent with linkage relationships known to be conserved between cattle and mice. The mouse genes for uroplakins IB and III were not mapped because the mouse genomic DNA fragments reactive with each probe were invariant among the inbred strains tested. Although the stoichiometry of AUM proteins is nearly constant, the fact that the uroplakin genes are unlinked indicates that their expression must be independently regulated. Our results also suggest likely positions for two human uroplakin genes and should facilitate further analysis of their possible involvement in disease.  相似文献   
43.
汉族ABO血型的皮纹特征分析   总被引:2,自引:1,他引:1  
作者对芜湖地区382例(男220人;女162人)汉族ABO血型的皮纹特征进行了分析,其中O型130人,A型113人,B型101人,AB型38人。分析比较了指纹类型、指纹组合格局、指嵴纹计数、掌嵴纹计数、atd角,掌部真实花纹,掌褶纹和拇趾球纹等项参数,结果表明,ABO各血型的皮纹参数间有若干统计学差异。  相似文献   
44.
核酶Ripc对HBV基因体外转录物的作用   总被引:11,自引:0,他引:11  
王平  徐炜 《病毒学报》1993,9(3):278-280
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用Aedans标记肌动蛋白单体G-Actin上Cys374残基作为探针,研究了稀土离子Ce~(3+)与G-Actin的结合及引起的微构象变化。Ce~(3+)在低浓度(Ce~(3+)/Actin摩尔比<1)和Ca~(2+)竞争G-Actin上二价离子的高亲合位点。Ce~(3+)取代Ca~(2+)引起Aedans荧光强度增强与Mg~(2+)取代Ca~(2+)的结果相同。Ce~(3+)/Actin>l则导致Aedans荧光强度下降。说明Ce~(3+)在高低两种浓度条件下结合的位点及对Cvs374的微构象的影响不同。时间分辩测得的Aedans荧光寿命也支持这一结论。CD谱结果表明Ce~(3+)/Actin<0.4,Actin的二级结构增加,大于0.4又导致其失去。Ce~(3+)-Actin在有/无游离ATP时用聚合液诱导的聚合结果表明,无游离ATP时,极低浓度Ce~(3+)促进聚合,高浓度虽有促进但有所减弱;有游离ATP时,Ce~(3+)/Actin在实验范围内促进聚合。  相似文献   
49.
Phosphatidylinositol 3-kinase (PI-3 kinase) is implicated in the regulation of diverse cellular processes, including insulin-stimulated glucose transport. PI-3 kinase is composed of a 110-kDa catalytic subunit and an 85-kDa regulatory subunit. Here, we describe p55PIK, a new regulatory subunit that was isolated by screening expression libraries with tyrosine-phosphorylated insulin receptor substrate 1 (IRS-1). p55PIK is composed of a unique 30-residue NH2 terminus followed by a proline-rich motif and two Src homology 2 (SH2) domains with significant sequence identify to those in p85. p55PIK mRNA is expressed early during development, remains abundant in adult mouse brain and testis tissue, and is detectable in adult adipocytes and heart and kidney tissues. p55PIK forms a stable complex with p110, and it associates with IRS-1 during insulin stimulation. Moreover, the activated insulin receptor phosphorylates p55PIK in Sf9 cells, and insulin stimulates p55PIK phosphorylation in CHOIR/p55PIK cells. The unique features of p55PIK suggest that it is important in receptor signaling.  相似文献   
50.
From plate cultures of Campylobacter jejuni grown in room air a particulate protein of 62 kDa was isolated by ion-exchange chromatography. The protein had a square shape from the side view but when viewed from the top it had a star-shaped structure. The molecular size of the whole particle determined by gel filtration was 850 kDa which suggested the presence of 14 subunits of 62 kDa in each particle. The N-terminal 37 amino residues showed more than 80% homology with the sequence of these heat shock protein (HSP) 60 homologs of Chlamydia trachomatis, Helicobacter pylori, and Escherichia coli (GroEL). This protein is immunologically cross-reactive with the antiserum for the 60-kDa HSP of Yersinia enterocolitica. Production of the 62-kDa protein increased under heat stress and growth in an aerobic atmospheric environment. From these observations we concluded that the 62-kDa protein is a Campylobacter stress protein (Cj62) which belongs to the HSP 60 family.  相似文献   
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