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    Evolutionary analysis of classical HLA class I and II genes suggests that recent positive selection acted on DPB1*04:01 in Japanese population.
    Kawashima, M ; Ohashi, J ; Nishida, N ; Tokunaga, K ; Harpending, H (Public Library of Science (PLoS), 2012)
    The human leukocyte antigen (HLA) genes exhibit the highest degree of polymorphism in the human genome. This high degree of variation at classical HLA class I and class II loci has been maintained by balancing selection for a long evolutionary time. However, little is known about recent positive selection acting on specific HLA alleles in a local population. To detect the signature of recent positive selection, we genotyped six HLA loci, HLA-A, HLA-B, HLA-C, HLA-DRB1, HLA-DQB1, and HLA-DPB1 in 418 Japanese subjects, and then assessed the haplotype homozygosity (HH) of each HLA allele. There were 120 HLA alleles across the six loci. Among the 80 HLA alleles with frequencies of more than 1%, DPB1*04∶01, which had a frequency of 6.1%, showed exceptionally high HH (0.53). This finding raises the possibility that recent positive selection has acted on DPB1*04∶01. The DPB1*04∶01 allele, which was present in the most common 6-locus HLA haplotype (4.4%), A*33∶03-C*14∶03-B*44∶03-DRB1*13∶02-DQB1*06∶04-DPB1*04∶01, seems to have flowed from the Korean peninsula to the Japanese archipelago in the Yayoi period. A stochastic simulation approach indicated that the strong linkage disequilibrium between DQB1*06∶04 and DPB1*04∶01 observed in Japanese cannot be explained without positive selection favoring DPB1*04∶01. The selection coefficient of DPB1*04∶01 was estimated as 0.041 (95% credible interval 0.021-0.077). Our results suggest that DPB1*04∶01 has recently undergone strong positive selection in Japanese population.
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    Association of human leukocyte antigen with interstitial lung disease in rheumatoid arthritis: a protective role for shared epitope.
    Furukawa, H ; Oka, S ; Shimada, K ; Sugii, S ; Ohashi, J ; Matsui, T ; Ikenaka, T ; Nakayama, H ; Hashimoto, A ; Takaoka, H ; Arinuma, Y ; Okazaki, Y ; Futami, H ; Komiya, A ; Fukui, N ; Nakamura, T ; Migita, K ; Suda, A ; Nagaoka, S ; Tsuchiya, N ; Tohma, S ; Goldberg, AC (Public Library of Science (PLoS), 2012)
    INTRODUCTION: Interstitial Lung Disease (ILD) is frequently associated with Rheumatoid Arthritis (RA) as one of extra-articular manifestations. Many studies for Human Leukocyte Antigen (HLA) allelic association with RA have been reported, but few have been validated in an RA subpopulation with ILD. In this study, we investigated the association of HLA class II alleles with ILD in RA. METHODS: An association study was conducted on HLA-DRB1, DQB1, and DPB1 in 450 Japanese RA patients that were or were not diagnosed with ILD, based on the findings of computed tomography images of the chest. RESULTS: Unexpectedly, HLA-DRB1*04 (corrected P [Pc] = 0.0054, odds ratio [OR] 0.57), shared epitope (SE) (P = 0.0055, OR 0.66) and DQB1*04 (Pc = 0.0036, OR 0.57) were associated with significantly decreased risk of ILD. In contrast, DRB1*16 (Pc = 0.0372, OR 15.21), DR2 serological group (DRB1*15 and *16 alleles) (P = 0.0020, OR 1.75) and DQB1*06 (Pc = 0.0333, OR 1.57, respectively) were significantly associated with risk of ILD. CONCLUSION: HLA-DRB1 SE was associated with reduced, while DR2 serological group (DRB1*15 and *16) with increased, risk for ILD in Japanese patients with RA.
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    Association of IFNGR2 gene polymorphisms with pulmonary tuberculosis among the Vietnamese.
    Hijikata, M ; Shojima, J ; Matsushita, I ; Tokunaga, K ; Ohashi, J ; Hang, NTL ; Horie, T ; Sakurada, S ; Hoang, NP ; Thuong, PH ; Lien, LT ; Keicho, N (Springer Science and Business Media LLC, 2012-05)
    Interferon-γ (IFN-γ) is a key molecule of T helper 1 (Th1)-immune response against tuberculosis (TB), and rare genetic defects of IFN-γ receptors cause disseminated mycobacterial infection. The aim of the present study was to investigate whether genetic polymorphisms found in the Th1-immune response genes play a role in TB. In our study, DNA samples were collected from two series of cases including 832 patients with new smear-positive TB and 506 unrelated individuals with no history of TB in the general population of Hanoi, Vietnam. Alleles of eight microsatellite markers located around Th1-immune response-related genes and single nucleotide polymorphisms near the promising microsatellites were genotyped. A set of polymorphisms within the interferon gamma receptor 2 gene (IFNGR2) showed a significant association with protection against TB (P = 0.00054). Resistant alleles tend to be less frequently found in younger age at diagnosis (P = 0.011). Luciferase assays revealed high transcriptional activity of the promoter segment in linkage disequilibrium with resistant alleles. We conclude that the polymorphisms of IFNGR2 may confer resistance to the TB development of newly infected individuals. Contribution of the genetic factors to TB appeared to be different depending on age at diagnosis.
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    Significant association of KIR2DL3-HLA-C1 combination with cerebral malaria and implications for co-evolution of KIR and HLA.
    Hirayasu, K ; Ohashi, J ; Kashiwase, K ; Hananantachai, H ; Naka, I ; Ogawa, A ; Takanashi, M ; Satake, M ; Nakajima, K ; Parham, P ; Arase, H ; Tokunaga, K ; Patarapotikul, J ; Yabe, T ; Kazura, JW (Public Library of Science (PLoS), 2012)
    Cerebral malaria is a major, life-threatening complication of Plasmodium falciparum malaria, and has very high mortality rate. In murine malaria models, natural killer (NK) cell responses have been shown to play a crucial role in the pathogenesis of cerebral malaria. To investigate the role of NK cells in the developmental process of human cerebral malaria, we conducted a case-control study examining genotypes for killer immunoglobulin-like receptors (KIR) and their human leukocyte antigen (HLA) class I ligands in 477 malaria patients. We found that the combination of KIR2DL3 and its cognate HLA-C1 ligand was significantly associated with the development of cerebral malaria when compared with non-cerebral malaria (odds ratio 3.14, 95% confidence interval 1.52-6.48, P = 0.00079, corrected P = 0.02). In contrast, no other KIR-HLA pairs showed a significant association with cerebral malaria, suggesting that the NK cell repertoire shaped by the KIR2DL3-HLA-C1 interaction shows certain functional responses that facilitate development of cerebral malaria. Furthermore, the frequency of the KIR2DL3-HLA-C1 combination was found to be significantly lower in malaria high-endemic populations. These results suggest that natural selection has reduced the frequency of the KIR2DL3-HLA-C1 combination in malaria high-endemic populations because of the propensity of interaction between KIR2DL3 and C1 to favor development of cerebral malaria. Our findings provide one possible explanation for KIR-HLA co-evolution driven by a microbial pathogen, and its effect on the global distribution of malaria, KIR and HLA.
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    Drosophila Rbp6 Is an Orthologue of Vertebrate Msi-1 and Msi-2, but Does Not Function Redundantly with dMsi to Regulate Germline Stem Cell Behaviour
    Siddall, NA ; Kalcina, M ; Johanson, TM ; Monk, AC ; Casagranda, F ; Been, RP ; McLaughlin, EA ; Hime, GR ; Jennings, B (PUBLIC LIBRARY SCIENCE, 2012-11-27)
    The vertebrate RNA-binding proteins, Musashi-1 (Msi-1) and Musashi-2 (Msi-2) are expressed in multiple stem cell populations. A role for Musashi proteins in preventing stem cell differentiation has been suggested from genetic analysis of the Drosophila family member, dMsi, and both vertebrate Msi proteins function co-operatively to regulate neural stem cell behaviour. Here we have identified a second Drosophila Msi family member, Rbp6, which shares more amino acid identity with vertebrate Msi-1 and Msi-2 than dMsi. We generated an antibody that detects most Rbp6 splice isoforms and show that Rbp6 is expressed in multiple tissues throughout development. However, Rbp6 deletion mutants generated in this study are viable and fertile, and show only minor defects. We used Drosophila spermatogonial germline stem cells (GSC's) as a model to test whether Drosophila Msi proteins function redundantly to regulate stem cell behaviour. However, like vertebrate Msi-1 and Msi-2, Rbp6 and Msi do not appear to be co-expressed in spermatogenic GSC's and do not function co-operatively in the regulation of GSC maintenance. Thus while two Msi family members are present in Drosophila, the function of the family members have diverged.
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    Parmenides and Mulla Sadra: The Mystical Journey to Being
    Kamal, M ; Paya, A (ICAS Press, 2012)
    A comparative analysis of the philosophical views of Parmenides and Mulla Sadra is established on two assumptions. First, it is argued that both thinkers have developed their ontology under divine instructions revealed to them in a mystical experience. Second, in the reconstruction of their mystical experience asserted the priority of 'Being' as the sole reality and the foundation of knowledge and the existence of the world.
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    The Medical Humanities and the Perils of Curricular Integration
    Chiavaroli, N ; Ellwood, C (SPRINGER, 2012-12)
    The advent of integration as a feature of contemporary medical curricula can be seen as an advantage for the medical humanities in that it provides a clear implementation strategy for the inclusion of medical humanities content and/or perspectives, while also making its relevance to medical education more apparent. This paper discusses an example of integration of humanities content into a graduate medical course, raises questions about the desirability of an exclusively integrated approach, and argues for the value of retaining a discrete and coherent disciplinary presence for the medical humanities in medical curricula.
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    Aboriginal Autonomy and Its Place in Taiwan's National Trauma Narrative
    Smith, CA (FOREIGN LANGUAGE PUBL, 2012-12-01)
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    Change, Reputation, and Hair: A Female Rite of Passage in Mtha' ba Village
    ROCHE, G ; Blo bzang tshe ring, ; Don 'grub sgrol ma, ; Stuart, K (Asian Highlands Perspectives, 2012)