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1.
Torkel Wadström Siiri Hirmo Hajdi Novak Antonio Guzman Martina Ringnér-Pantzar Meeme Utt Pär Aleljung 《Current microbiology》1997,34(5):267-272
Helicobacter pylori adhere to Kato III and Hela S3
cells in monolayer cultures. To explore whether cell surface glycoconjugates
on these two cell lines mediate binding of H. pylori, various
carbohydrates, glycoproteins, and glycolipids were tested to inhibit H.
pylori cell adhesion. The adhesion was measured (i) with a urease-based
assay and (ii) by cells stained with fluorescein. Sodium periodate and
sialidase treatment (but not α- or β-galactosidase, heparitinase,
lysozyme, or trypsin) inhibited H. pylori binding to both cell lines.
Sulfatides and sulfated glycoconjugates (50 μg/ml) but not heparin or a
number of simple carbohydrates inhibited binding (1 mg/ml). The two H.
pylori strains studied (CCUG 17874 and strain 25) showed high binding of
soluble 125I-labeled heparin and other sulfated carbohydrate
compounds.
Received: 5 July 1996 / Accepted: 17 October 1996 相似文献
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Alena Kushniarevich Larysa Sivitskaya Nina Danilenko Tadeush Novogrodskii Iosif Tsybovsky Anna Kiseleva Svetlana Kotova Gyaneshwer Chaubey Ene Metspalu Hovhannes Sahakyan Ardeshir Bahmanimehr Maere Reidla Siiri Rootsi Jüri Parik Tuuli Reisberg Alessandro Achilli Baharak Hooshiar Kashani Francesca Gandini Anna Olivieri Doron M. Behar Antonio Torroni Oleg Davydenko Richard Villems 《PloS one》2013,8(6)
Ethnic Belarusians make up more than 80% of the nine and half million people inhabiting the Republic of Belarus. Belarusians together with Ukrainians and Russians represent the East Slavic linguistic group, largest both in numbers and territory, inhabiting East Europe alongside Baltic-, Finno-Permic- and Turkic-speaking people. Till date, only a limited number of low resolution genetic studies have been performed on this population. Therefore, with the phylogeographic analysis of 565 Y-chromosomes and 267 mitochondrial DNAs from six well covered geographic sub-regions of Belarus we strove to complement the existing genetic profile of eastern Europeans. Our results reveal that around 80% of the paternal Belarusian gene pool is composed of R1a, I2a and N1c Y-chromosome haplogroups – a profile which is very similar to the two other eastern European populations – Ukrainians and Russians. The maternal Belarusian gene pool encompasses a full range of West Eurasian haplogroups and agrees well with the genetic structure of central-east European populations. Our data attest that latitudinal gradients characterize the variation of the uniparentally transmitted gene pools of modern Belarusians. In particular, the Y-chromosome reflects movements of people in central-east Europe, starting probably as early as the beginning of the Holocene. Furthermore, the matrilineal legacy of Belarusians retains two rare mitochondrial DNA haplogroups, N1a3 and N3, whose phylogeographies were explored in detail after de novo sequencing of 20 and 13 complete mitogenomes, respectively, from all over Eurasia. Our phylogeographic analyses reveal that two mitochondrial DNA lineages, N3 and N1a3, both of Middle Eastern origin, might mark distinct events of matrilineal gene flow to Europe: during the mid-Holocene period and around the Pleistocene-Holocene transition, respectively. 相似文献
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Klarić IM Salihović MP Lauc LB Zhivotovsky LA Rootsi S Janićijević B 《American journal of physical anthropology》2009,138(3):333-342
The Bayash are a branch of Romanian speaking Roma living dispersedly in Central, Eastern, and Southeastern Europe. To better understand the molecular architecture and origin of the Croatian Bayash paternal gene pool, 151 Bayash Y chromosomes were analyzed for 16 SNPs and 17 STRs and compared with European Romani and non-Romani majority populations from Europe, Turkey, and South Asia. Two main layers of Bayash paternal gene pool were identified: ancestral (Indian) and recent (European). The reduced diversity and expansion signals of H1a patrilineages imply descent from closely related paternal ancestors who could have settled in the Indian subcontinent, possibly as early as between the eighth and tenth centuries AD. The recent layer of the Bayash paternal pool is dominated by a specific subset of E1b1b1a lineages that are not found in the Balkan majority populations. At least two private mutational events occurred in the Bayash during their migrations from the southern Balkans toward Romania. Additional admixture, evident in the low frequencies of typical European haplogroups, J2, R1a, I1, R1b1b2, G, and I2a, took place primarily during the early Bayash settlement in the Balkans and the Romani bondage in Romania. Our results indicate two phenomena in the Bayash and analyzed Roma: a significant preservation of ancestral H1a haplotypes as a result of considerable, but variable level of endogamy and isolation and differential distribution of less frequent, but typical European lineages due to different patterns of the early demographic history in Europe marked by differential admixture and genetic drift. 相似文献
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Mari J?rve Lev A. Zhivotovsky Siiri Rootsi Hela Help Evgeny I. Rogaev Elza K. Khusnutdinova Toomas Kivisild Juan J. Sanchez 《PloS one》2009,4(9)
Background
Polymorphic Y chromosome short tandem repeats (STRs) have been widely used in population genetic and evolutionary studies. Compared to di-, tri-, and tetranucleotide repeats, STRs with longer repeat units occur more rarely and are far less commonly used.Principal Findings
In order to study the evolutionary dynamics of STRs according to repeat unit size, we analysed variation at 24 Y chromosome repeat loci: 1 tri-, 14 tetra-, 7 penta-, and 2 hexanucleotide loci. According to our results, penta- and hexanucleotide repeats have approximately two times lower repeat variance and diversity than tri- and tetranucleotide repeats, indicating that their mutation rate is about half of that of tri- and tetranucleotide repeats. Thus, STR markers with longer repeat units are more robust in distinguishing Y chromosome haplogroups and, in some cases, phylogenetic splits within established haplogroups.Conclusions
Our findings suggest that Y chromosome STRs of increased repeat unit size have a lower rate of evolution, which has significant relevance in population genetic and evolutionary studies. 相似文献6.
Cornelis MC Monda KL Yu K Paynter N Azzato EM Bennett SN Berndt SI Boerwinkle E Chanock S Chatterjee N Couper D Curhan G Heiss G Hu FB Hunter DJ Jacobs K Jensen MK Kraft P Landi MT Nettleton JA Purdue MP Rajaraman P Rimm EB Rose LM Rothman N Silverman D Stolzenberg-Solomon R Subar A Yeager M Chasman DI van Dam RM Caporaso NE 《PLoS genetics》2011,7(4):e1002033
We report the first genome-wide association study of habitual caffeine intake. We included 47,341 individuals of European descent based on five population-based studies within the United States. In a meta-analysis adjusted for age, sex, smoking, and eigenvectors of population variation, two loci achieved genome-wide significance: 7p21 (P = 2.4 × 10(-19)), near AHR, and 15q24 (P = 5.2 × 10(-14)), between CYP1A1 and CYP1A2. Both the AHR and CYP1A2 genes are biologically plausible candidates as CYP1A2 metabolizes caffeine and AHR regulates CYP1A2. 相似文献
7.
Begg GE Holman SR Stokes PH Matthews JM Graham RM Iismaa SE 《The Journal of biological chemistry》2006,281(18):12603-12609
Transglutaminase type 2 (TG2; also known as G(h)) is a multifunctional protein involved in diverse cellular processes. It has two well characterized enzyme activities: receptor-stimulated signaling that requires GTP binding and calcium-activated transamidation or cross-linking that is inhibited by GTP. In addition to the GDP binding residues identified from the human TG2 crystal structure (Liu, S., Cerione, R. A., and Clardy, J. (2002) Proc. Natl. Acad. Sci. U. S. A. 99, 2743-2747), we have previously implicated Ser171 in GTP binding, as binding is lost with glutamate substitution (Iismaa, S. E., Wu, M.-J., Nanda, N., Church, W. B., and Graham, R. M. (2000) J. Biol. Chem. 275, 18259-18265). Here, we have shown that alanine substitution of homologous residues in rat TG2 (Phe174 in the core domain or Arg476, Arg478, or Arg579 in barrel 1) does not affect TG activity but reduces or abolishes GTP binding and GTPgammaS inhibition of TG activity in vitro, indicating that these residues are important in GTP binding. Alanine substitution of Ser171 does not impair GTP binding, indicating this residue does not interact directly with GTP. Arg579 is particularly important for GTP binding, as isothermal titration calorimetry demonstrated a 100-fold reduction in GTP binding affinity by the R579A mutant. Unlike wild-type TG2 or its S171E or F174A mutants, which are sensitive to both trypsin and mu-calpain digestion, R579A is inherently more resistant to mu-calpain, but not trypsin, digestion, indicating reduced accessibility and/or flexibility of this mutant in the region of the calpain cleavage site(s). Basal TG activity of intact R579A stable SH-SY5Y neuroblastoma cell transfectants was slightly increased relative to wild-type transfectants and, in contrast to the TG activity of the latter, was further stimulated by muscarinic receptor-activated calcium mobilization. Thus, loss of GTP binding sensitizes TG2 to intracellular calcium concentrations. These findings are consistent with the notion that intracellularly, under physiological conditions, TG2 is maintained largely as a latent enzyme, its calcium-activated cross-linking activity being suppressed allosterically by guanine nucleotide binding. 相似文献
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Y-chromosomal diversity in Europe is clinal and influenced primarily by geography, rather than by language 总被引:15,自引:4,他引:11 下载免费PDF全文
Rosser ZH Zerjal T Hurles ME Adojaan M Alavantic D Amorim A Amos W Armenteros M Arroyo E Barbujani G Beckman G Beckman L Bertranpetit J Bosch E Bradley DG Brede G Cooper G Côrte-Real HB de Knijff P Decorte R Dubrova YE Evgrafov O Gilissen A Glisic S Gölge M Hill EW Jeziorowska A Kalaydjieva L Kayser M Kivisild T Kravchenko SA Krumina A Kucinskas V Lavinha J Livshits LA Malaspina P Maria S McElreavey K Meitinger TA Mikelsaar AV Mitchell RJ Nafa K Nicholson J Nørby S Pandya A Parik J Patsalis PC 《American journal of human genetics》2000,67(6):1526-1543
Clinal patterns of autosomal genetic diversity within Europe have been interpreted in previous studies in terms of a Neolithic demic diffusion model for the spread of agriculture; in contrast, studies using mtDNA have traced many founding lineages to the Paleolithic and have not shown strongly clinal variation. We have used 11 human Y-chromosomal biallelic polymorphisms, defining 10 haplogroups, to analyze a sample of 3,616 Y chromosomes belonging to 47 European and circum-European populations. Patterns of geographic differentiation are highly nonrandom, and, when they are assessed using spatial autocorrelation analysis, they show significant clines for five of six haplogroups analyzed. Clines for two haplogroups, representing 45% of the chromosomes, are continentwide and consistent with the demic diffusion hypothesis. Clines for three other haplogroups each have different foci and are more regionally restricted and are likely to reflect distinct population movements, including one from north of the Black Sea. Principal-components analysis suggests that populations are related primarily on the basis of geography, rather than on the basis of linguistic affinity. This is confirmed in Mantel tests, which show a strong and highly significant partial correlation between genetics and geography but a low, nonsignificant partial correlation between genetics and language. Genetic-barrier analysis also indicates the primacy of geography in the shaping of patterns of variation. These patterns retain a strong signal of expansion from the Near East but also suggest that the demographic history of Europe has been complex and influenced by other major population movements, as well as by linguistic and geographic heterogeneities and the effects of drift. 相似文献
9.
Phylogeography of Y-chromosome haplogroup I reveals distinct domains of prehistoric gene flow in europe 总被引:14,自引:2,他引:12 下载免费PDF全文
Rootsi S Magri C Kivisild T Benuzzi G Help H Bermisheva M Kutuev I Barać L Pericić M Balanovsky O Pshenichnov A Dion D Grobei M Zhivotovsky LA Battaglia V Achilli A Al-Zahery N Parik J King R Cinnioğlu C Khusnutdinova E Rudan P Balanovska E Scheffrahn W Simonescu M Brehm A Goncalves R Rosa A Moisan JP Chaventre A Ferak V Füredi S Oefner PJ Shen P Beckman L Mikerezi I Terzić R Primorac D Cambon-Thomsen A Krumina A Torroni A Underhill PA Santachiara-Benerecetti AS Villems R Semino O 《American journal of human genetics》2004,75(1):128-137
To investigate which aspects of contemporary human Y-chromosome variation in Europe are characteristic of primary colonization, late-glacial expansions from refuge areas, Neolithic dispersals, or more recent events of gene flow, we have analyzed, in detail, haplogroup I (Hg I), the only major clade of the Y phylogeny that is widespread over Europe but virtually absent elsewhere. The analysis of 1,104 Hg I Y chromosomes, which were identified in the survey of 7,574 males from 60 population samples, revealed several subclades with distinct geographic distributions. Subclade I1a accounts for most of Hg I in Scandinavia, with a rapidly decreasing frequency toward both the East European Plain and the Atlantic fringe, but microsatellite diversity reveals that France could be the source region of the early spread of both I1a and the less common I1c. Also, I1b*, which extends from the eastern Adriatic to eastern Europe and declines noticeably toward the southern Balkans and abruptly toward the periphery of northern Italy, probably diffused after the Last Glacial Maximum from a homeland in eastern Europe or the Balkans. In contrast, I1b2 most likely arose in southern France/Iberia. Similarly to the other subclades, it underwent a postglacial expansion and marked the human colonization of Sardinia ~9,000 years ago. 相似文献
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