排序方式: 共有17条查询结果,搜索用时 109 毫秒
11.
Cvjetan S Tolk HV Lauc LB Colak I Dordević D Efremovska L Janićijević B Kvesić A Klarić IM Metspalu E Pericić M Parik J Popović D Sijacki A Terzić R Villems R Rudan P 《Collegium antropologicum》2004,28(1):193-198
Mitochondrial DNA polymorphisms were analyzed in of 1,610 randomly chosen adult men from 11 different regions from southeastern Europe (Croatians, Bosnians and Herzegovinians, Serbians, Macedonians and Macedonian Romani). MtDNA HVS-I region together with RFLP sites diagnostic for main Euroasian and African mtDNA haplogroups were typed to determine haplogroup frequency distribution. The most frequent haplogroup in studied populations was H with the exception of Macedonian Romani among whom the most frequent were South Asian (Indian) specific variants of haplogroup M. The multidimensional scaling plot showed two clusters of populations and two outliers (Macedonian Romani and the most distant from mainland Croatian island of Korcula). The first cluster was formed by populations from three Croatian islands (Hvar, Krk and Brac) and the second cluster was formed by Macedonians, Serbians, Croatians from mainland and coast, Herzegovinians, Bosnians, Slovenians, Poles and Russians. The present analysis does not address a precise evaluation of phylogenetic relations of studied populations although some conclusions about historical migrations could be noticed. More extended conclusions will be possible after deeper phylogenetic and statistical analyses. 相似文献
12.
Lejla Kovacevic Kristiina Tambets Anne-Mai Ilum?e Alena Kushniarevich Bayazit Yunusbayev Anu Solnik Tamer Bego Dragan Primorac Vedrana Skaro Andreja Leskovac Zlatko Jakovski Katja Drobnic Helle-Viivi Tolk Sandra Kovacevic Pavao Rudan Ene Metspalu Damir Marjanovic 《PloS one》2014,9(8)
Contemporary inhabitants of the Balkan Peninsula belong to several ethnic groups of diverse cultural background. In this study, three ethnic groups from Bosnia and Herzegovina - Bosniacs, Bosnian Croats and Bosnian Serbs - as well as the populations of Serbians, Croatians, Macedonians from the former Yugoslav Republic of Macedonia, Montenegrins and Kosovars have been characterized for the genetic variation of 660 000 genome-wide autosomal single nucleotide polymorphisms and for haploid markers. New autosomal data of the 70 individuals together with previously published data of 20 individuals from the populations of the Western Balkan region in a context of 695 samples of global range have been analysed. Comparison of the variation data of autosomal and haploid lineages of the studied Western Balkan populations reveals a concordance of the data in both sets and the genetic uniformity of the studied populations, especially of Western South-Slavic speakers. The genetic variation of Western Balkan populations reveals the continuity between the Middle East and Europe via the Balkan region and supports the scenario that one of the major routes of ancient gene flows and admixture went through the Balkan Peninsula. 相似文献
13.
Kinetics of a collagen-like polypeptide fragmentation after mid-IR free-electron laser ablation 下载免费PDF全文
Zavalin A Hachey DL Sundaramoorthy M Banerjee S Morgan S Feldman L Tolk N Piston DW 《Biophysical journal》2008,95(3):1371-1381
Tissue ablation with mid-infrared irradiation tuned to collagen vibrational modes results in minimal collateral damage. The hypothesis for this effect includes selective scission of protein molecules and excitation of surrounding water molecules, with the scission process currently favored. In this article, we describe the postablation infrared spectral decay kinetics in a model collagen-like peptide (Pro-Pro-Gly)10. We find that the decay is exponential with different decay times for other, simpler dipeptides. Furthermore, we find that collagen-like polypeptides, such as (Pro-Pro-Gly)10, show multiple decay times, indicating multiple scission locations and cross-linking to form longer chain molecules. In combination with data from high-resolution mass spectrometry, we interpret these products to result from the generation of reactive intermediates, such as free radicals, cyanate ions, and isocyanic acid, which can form cross-links and protein adducts. Our results lead to a more complete explanation of the reduced collateral damage resulting from infrared laser irradiation through a mechanism involving cross-linking in which collagen-like molecules form a network of cross-linked fibers. 相似文献
14.
The western and eastern roots of the Saami--the story of genetic "outliers" told by mitochondrial DNA and Y chromosomes 下载免费PDF全文
Tambets K Rootsi S Kivisild T Help H Serk P Loogväli EL Tolk HV Reidla M Metspalu E Pliss L Balanovsky O Pshenichnov A Balanovska E Gubina M Zhadanov S Osipova L Damba L Voevoda M Kutuev I Bermisheva M Khusnutdinova E Gusar V Grechanina E Parik J Pennarun E Richard C Chaventre A Moisan JP Barác L Pericić M Rudan P Terzić R Mikerezi I Krumina A Baumanis V Koziel S Rickards O De Stefano GF Anagnou N Pappa KI Michalodimitrakis E Ferák V Füredi S Komel R Beckman L Villems R 《American journal of human genetics》2004,74(4):661-682
The Saami are regarded as extreme genetic outliers among European populations. In this study, a high-resolution phylogenetic analysis of Saami genetic heritage was undertaken in a comprehensive context, through use of maternally inherited mitochondrial DNA (mtDNA) and paternally inherited Y-chromosomal variation. DNA variants present in the Saami were compared with those found in Europe and Siberia, through use of both new and previously published data from 445 Saami and 17,096 western Eurasian and Siberian mtDNA samples, as well as 127 Saami and 2,840 western Eurasian and Siberian Y-chromosome samples. It was shown that the “Saami motif” variant of mtDNA haplogroup U5b is present in a large area outside Scandinavia. A detailed phylogeographic analysis of one of the predominant Saami mtDNA haplogroups, U5b1b, which also includes the lineages of the “Saami motif,” was undertaken in 31 populations. The results indicate that the origin of U5b1b, as for the other predominant Saami haplogroup, V, is most likely in western, rather than eastern, Europe. Furthermore, an additional haplogroup (H1) spread among the Saami was virtually absent in 781 Samoyed and Ob-Ugric Siberians but was present in western and central European populations. The Y-chromosomal variety in the Saami is also consistent with their European ancestry. It suggests that the large genetic separation of the Saami from other Europeans is best explained by assuming that the Saami are descendants of a narrow, distinctive subset of Europeans. In particular, no evidence of a significant directional gene flow from extant aboriginal Siberian populations into the haploid gene pools of the Saami was found. 相似文献
15.
Chemically resolved imaging of biological cells and thin films by infrared scanning near-field optical microscopy 下载免费PDF全文
Cricenti A Generosi R Luce M Perfetti P Margaritondo G Talley D Sanghera JS Aggarwal ID Tolk NH Congiu-Castellano A Rizzo MA Piston DW 《Biophysical journal》2003,85(4):2705-2710
The infrared (IR) absorption of a biological system can potentially report on fundamentally important microchemical properties. For example, molecular IR profiles are known to change during increases in metabolic flux, protein phosphorylation, or proteolytic cleavage. However, practical implementation of intracellular IR imaging has been problematic because the diffraction limit of conventional infrared microscopy results in low spatial resolution. We have overcome this limitation by using an IR spectroscopic version of scanning near-field optical microscopy (SNOM), in conjunction with a tunable free-electron laser source. The results presented here clearly reveal different chemical constituents in thin films and biological cells. The space distribution of specific chemical species was obtained by taking SNOM images at IR wavelengths (lambda) corresponding to stretch absorption bands of common biochemical bonds, such as the amide bond. In our SNOM implementation, this chemical sensitivity is combined with a lateral resolution of 0.1 micro m ( approximately lambda/70), well below the diffraction limit of standard infrared microscopy. The potential applications of this approach touch virtually every aspect of the life sciences and medical research, as well as problems in materials science, chemistry, physics, and environmental research. 相似文献
16.
Torroni A Bandelt HJ Macaulay V Richards M Cruciani F Rengo C Martinez-Cabrera V Villems R Kivisild T Metspalu E Parik J Tolk HV Tambets K Forster P Karger B Francalacci P Rudan P Janicijevic B Rickards O Savontaus ML Huoponen K Laitinen V Koivumäki S Sykes B Hickey E Novelletto A Moral P Sellitto D Coppa A Al-Zaheri N Santachiara-Benerecetti AS Semino O Scozzari R 《American journal of human genetics》2001,69(4):844-852
Mitochondrial HVS-I sequences from 10,365 subjects belonging to 56 populations/geographical regions of western Eurasia and northern Africa were first surveyed for the presence of the T-->C transition at nucleotide position 16298, a mutation which has previously been shown to characterize haplogroup V mtDNAs. All mtDNAs with this mutation were then screened for a number of diagnostic RFLP sites, revealing two major subsets of mtDNAs. One is haplogroup V proper, and the other has been termed "pre*V," since it predates V phylogenetically. The rather uncommon pre*V tends to be scattered throughout Europe (and northwestern Africa), whereas V attains two peaks of frequency: one situated in southwestern Europe and one in the Saami of northern Scandinavia. Geographical distributions and ages support the scenario that pre*V originated in Europe before the Last Glacial Maximum (LGM), whereas the more recently derived haplogroup V arose in a southwestern European refugium soon after the LGM. The arrival of V in eastern/central Europe, however, occurred much later, possibly with (post-)Neolithic contacts. The distribution of haplogroup V mtDNAs in modern European populations would thus, at least in part, reflect the pattern of postglacial human recolonization from that refugium, affecting even the Saami. Overall, the present study shows that the dissection of mtDNA variation into small and well-defined evolutionary units is an essential step in the identification of spatial frequency patterns. Mass screening of a few markers identified using complete mtDNA sequences promises to be an efficient strategy for inferring features of human prehistory. 相似文献
17.
Koen JP Verhees Nicholas AM Pansters Hoeke A Baarsma Alexander HV Remels Astrid Haegens Chiel C de Theije Annemie MWJ Schols Reinoud Gosens Ramon CJ Langen 《Respiratory research》2013,14(1):117