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Haplogroup R1a1‐M198 is a major clade of Y chromosomal haplogroups which is distributed all across Eurasia. To this date, many efforts have been made to identify large SNP‐based subgroups and migration patterns of this haplogroup. The origin and spread of R1a1 chromosomes in Eurasia has, however, remained unknown due to the lack of downstream SNPs within the R1a1 haplogroup. Since the discovery of R1a1‐M458, this is the first scientific attempt to divide haplogroup R1a1‐M198 into multiple SNP‐based sub‐haplogroups. We have genotyped 217 R1a1‐M198 samples from seven different population groups at M458, as well as the Z280 and Z93 SNPs recently identified from the “1000 Genomes Project”. The two additional binary markers present an effective tool because now more than 98% of the samples analyzed assign to one of the three sub‐haplogroups. R1a1‐M458 and R1a1‐Z280 were typical for the Hungarian population groups, whereas R1a1‐Z93 was typical for Malaysian Indians and the Hungarian Roma. Inner and Central Asia is an overlap zone for the R1a1‐Z280 and R1a1‐Z93 lineages. This pattern implies that an early differentiation zone of R1a1‐M198 conceivably occurred somewhere within the Eurasian Steppes or the Middle East and Caucasus region as they lie between South Asia and Eastern Europe. The detection of the Z93 paternal genetic imprint in the Hungarian Roma gene pool is consistent with South Asian ancestry and amends the view that H1a‐M82 is their only discernible paternal lineage of Indian heritage. © 2012 Wiley Periodicals, Inc.  相似文献   
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Inflammatory responses are controlled through members of the interleukin-1 receptor (IL-1R)/Toll-like receptor superfamily. Our earlier work demonstrates that the IL-1 receptor type 1 (IL-1RI) co-receptor, Toll-like and IL-1 receptor regulator (TILRR), amplifies IL-1 activation of NF-κB and inflammatory genes. Here we show that TILRR similarly promotes IL-1-induced anti-apoptotic signals and reduces caspase-3 activity. Further, the TILRR-induced effects on cell survival and inflammatory responses are controlled through distinct parts of the IL-1RI regulatory Toll IL-1 receptor (TIR) domain. Alanine-scanning mutagenesis identified a functional TILRR mutant (R425A), which blocked increases in cell survival and upstream activation of Akt but had no effect on amplification of MyD88-dependent inflammatory responses. A second mutant (D448A) blocked TILRR potentiation of MyD88-dependent signals and inflammatory activation but had no impact on cell survival. Secondary structure predictions suggested that the mutations induce distinct alterations in the α-helical structure of the TILRR core protein. The results indicate a role for TILRR in selective amplification of NF-κB responses through IL-1RI and suggest that the specificity is determined by changes in receptor conformation and adapter protein recruitment.  相似文献   
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Signal transduction pathways activated by Toll-like Receptors and the IL-1 family of cytokines are fundamental to mounting an innate immune response and thus to clearing pathogens and promoting wound healing. Whilst mechanistic understanding of the regulation of innate signalling pathways has advanced considerably in recent years, there are still a number of critical controllers to be discovered. In order to characterise novel regulators of macrophage inflammation, we have carried out an extensive, cDNA-based forward genetic screen and identified 34 novel activators, based on their ability to induce the expression of cxcl2. Many are physiologically expressed in macrophages, although the majority of genes uncovered in our screen have not previously been linked to innate immunity. We show that expression of particular activators has profound but distinct impacts on LPS-induced inflammatory gene expression, including switch-type, amplifier and sensitiser behaviours. Furthermore, the novel genes identified here interact with the canonical inflammatory signalling network via specific mechanisms, as demonstrated by the use of dominant negative forms of IL1/TLR signalling mediators.  相似文献   
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Polymastiidae Gray, 1867 is a worldwide distributed sponge family, which has a great significance for understanding of the demosponge deep phylogeny since the former order Hadromerida Topsent, 1894 has been recently split based on the molecular evidence and a new separate order has been established for the polymastiids. However, molecular data obtained from Polymastiidae so far are scarce, while the phylogenetic reconstruction based on morphology has faced a deficit of characters along with the vagueness of their states. The present study is a phylogenetic reconstruction of Polymastiidae based on novel data on two molecular markers, cytochrome oxidase subunit I and large subunit ribosomal DNA, obtained from a broad set of species. Monophyly of the family and nonmonophyly of four polymastiid genera are revealed, suggesting a high level of homoplasy of morphological characters, which are therefore not an appropriate base for the natural classification of Polymastiidae. Although the presented phylogenies cannot yet provide an alternative classification scheme, several strongly supported clades, which may be used as reference points in future classification, are recovered and three taxonomic actions are proposed: transfer of one species from Radiella to Polymastia Bowerbank, 1862; transfer of three species from Radiella Schmidt, 1870 to Spinularia Gray, 1867; and the consequent abandonment of Radiella.  相似文献   
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Treatment of acute kidney injury has been hampered by the inability of a creatinine-based diagnosis to allow clinicians to intervene with timely treatments aimed at preventing further development of the disease to the point where renal replacement therapy is necessary or death occurs. Novel biomarkers of injury have been touted as the tool by which early detection can occur and, on that basis, novel treatments can be developed and delivered early in the disease process. Sufficient new biomarkers have been discovered and evaluated to expect that not one biomarker but a panel of biomarkers applied according to phase of injury, baseline renal function and comorbidities will be necessary for the early diagnosis of acute kidney injury. Issues of validation of these biomarkers remain, particularly in heterogeneous populations of critically ill patients. Nevertheless, we are rapidly moving towards an era where the diagnosis of acute kidney injury will be proactive rather than by the traditional diagnosis of exclusion.  相似文献   
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