31 research outputs found

    The genetic prehistory of the Greater Caucasus

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    5月16日,厦门大学人类学系、德国马普所、德国考古所、俄罗斯文化遗产联合会、奥地利维也纳大学人类学系、爱尔兰都柏林大学学院考古系、罗蒙诺索夫莫斯科国立大学考古系和人类学博物馆、俄罗斯国立东方艺术博物馆、俄罗斯联邦达吉斯坦考古与民族志研究所历史系、美国韦尔斯利学院人类学系、瑞士巴塞尔大学史前与考古科学研究所、德国国家遗产博物馆等36家单位的46位共同作者组成的国际合作团队在BioRxiv上预发表论文《The genetic prehistory of the Greater Caucasus》,厦门大学人类学系王传超研究员为论文的第一作者和通讯作者,也是该国际团队中的唯一一位来自中国的合作者。【Abstract】Archaeogenetic studies have described the formation of Eurasian 'steppe ancestry' as a mixture of Eastern and Caucasus hunter-gatherers. However, it remains unclear when and where this ancestry arose and whether it was related to a horizon of cultural innovations in the 4th millennium BCE that subsequently facilitated the advance of pastoral societies likely linked to the dispersal of Indo-European languages. To address this, we generated genome-wide SNP data from 45 prehistoric individuals along a 3000-year temporal transect in the North Caucasus. We observe a genetic separation between the groups of the Caucasus and those of the adjacent steppe. The Caucasus groups are genetically similar to contemporaneous populations south of it, suggesting that - unlike today - the Caucasus acted as a bridge rather than an insurmountable barrier to human movement. The steppe groups from Yamnaya and subsequent pastoralist cultures show evidence for previously undetected Anatolian farmer-related ancestry from different contact zones, while Steppe Maykop individuals harbour additional Upper Palaeolithic Siberian and Native American related ancestry.This work was funded by the Max Planck Society and the German Archaeological Institute (DAI). C.C.W. was funded by Nanqiang Outstanding Young Talents Program of Xiamen University (X2123302) and the Fundamental Research Funds for the Central Universities. 该研究由德国马普学会、德国考古所、厦门大学南强青年拔尖人才支持计划资助

    Ancient human genome-wide data from a 3000-year interval in the Caucasus corresponds with eco-geographic regions

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    Archaeogenetic studies have described the formation of Eurasian 'steppe ancestry' as a mixture of Eastern and Caucasus hunter-gatherers. However, it remains unclear when and where this ancestry arose and whether it was related to a horizon of cultural innovations in the 4 th millennium BCE that subsequently facilitated the advance of pastoral societies in Eurasia. Here we generated genome-wide SNP data from 45 prehistoric individuals along a 3000-year temporal transect in the North Caucasus. We observe a genetic separation between the groups of the Caucasus and those of the adjacent steppe. The northern Caucasus groups are genetically similar to contemporaneous populations south of it, suggesting human movement across the mountain range during the Bronze Age. The steppe groups from Yamnaya and subsequent pastoralist cultures show evidence for previously undetected farmer-related ancestry from different contact zones, while Steppe Maykop individuals harbour additional Upper Palaeolithic Siberian and Native American related ancestry

    The James Webb Space Telescope Mission

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    Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least 4m4m. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the 6.5m6.5m James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

    Early life environmental predictors of asthma age-of-onset

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    Prevention strategies that delay the onset of asthma may improve clinical outcomes. To identify early life environmental exposures associated with asthma age-of-onset and potential genetic modifiers of these exposures, we studied 1085 subjects with physician-diagnosed asthma and disease onset at or after age two. Subjects reported retrospectively on their exposure to 17 environmental factors before the age of two. The presence of individual or combinations of these early life exposures was then tested for association with variation in asthma age-of-onset. For exposures significantly associated with age-of-onset, we tested if 26 single nucleotide polymorphisms (SNP) with an established association with allergic disease significantly modified the effect of the exposure. Five environmental exposures were significantly associated with variation in asthma age-of-onset after correction for multiple testing: carpet at home (P = 6 × 10(-5)), a serious chest illness (P = 10(-4)), father a cigarette smoker (P = 6 × 10(-4)) and direct exposure to father's smoking (P = 3 × 10(-4)). Individuals with early childhood asthma onset, between the ages of two and six, were 1.4-fold (CI 1.1-1.9) more likely to report having lived in a house with carpet and 2.1-fold (CI 1.3-3.5) more likely to report suffering a serious chest illness before the age of two, than asthmatics with later disease onset. We further found these individual risks to increase to 3.2-fold (CI 1.7-6.0) if carpet exposure and suffering a serious chest illness co-occurred before age two. Paternal smoking exposures were less likely to be reported by asthmatics with early when compared to later disease onset (OR 0.5, CI 0.3-0.7). There were no significant SNP interactions with these environmental exposures after correction for multiple testing. Our results suggest that disease onset in individuals at a high-risk of developing asthma can potentially be delayed by avoiding exposure to carpet at home and preventing serious chest illnesses during the first 2 years of life

    Diagnostic approach to chronic dyspnoea in adults

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    Chronic dyspnoea, or breathlessness for more than four weeks duration, is a common symptom in adults presenting to primary and tertiary care. It often presents a diagnostic challenge due to the wide spectrum of underlying disease, which is multifactorial in approximately one third of cases. Challenges in diagnosis include an often non-diagnostic clinical assessment, difficulty in selecting the most appropriate investigations and correct speciality referral for further diagnostic assessment. In patients presenting with chronic dyspnoea, history and physical examination are often non-specific with key findings more useful as negative predictive factors. There is a broad range of simple to specialised investigations that may be utilised in the diagnostic work-up. Several diagnostic algorithms incorporating different tiers of investigations have been tested in studies of chronic dyspnoea patients but there is currently very limited data that test a diagnostic algorithm against standard clinical care. In this review we propose a diagnostic pathway with primary, secondary and tertiary level investigations for patients with chronic dyspnoea. This pathway is based on the combination of previously tested diagnostic algorithms in the literature, to assist clinicians in their diagnostic workup of chronic dyspnoea patients. Further research is needed to further evaluate diagnostic algorithms in this setting and to test this diagnostic pathway in clinical practice

    Diagnosis of the cause of chronic dyspnoea in primary and tertiary care: characterizing diagnostic confidence

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    Background: Chronic dyspnoea (breathlessness) in adults is a common symptom, the exact cause of which may be difficult to diagnose on initial presentation. We characterised the diagnostic complexity of chronic dyspnoea in primary care and tertiary care.Methods: This retrospective observational study screened consecutive referral letters of all adult patients referred to cardiology or respiratory clinics at a tertiary referral hospital, during May to June 2015. For patients referred due to chronic dyspnoea, data were analysed from the initial referral letter and subsequent specialist clinic letters for the 6-month time period after referral.Results: Of 1,370 patient referrals, 122 patients (mean age 63 y, 55% female) were referred due to chronic dyspnoea. One hundred and five patients (86%) were referred from primary care and 17 (14%) from other hospital clinics. Sixty-one percent were referred with an evident diagnosis (referrer was confident of the initial diagnosis), whereas 39% had non-evident or unclear diagnoses. By 6 months after referral, a definitive final diagnosis had been determined by the specialist clinics in 62% of patients. The majority of patients had been referred appropriately to a cardiology or respiratory clinic, based on the final diagnosis. However, only 26% of diagnoses were fully concordant between the initial referrer diagnosis and the final specialist clinic diagnosis, with 26% being partially concordant and 48% non-concordant. Diagnostic certainty of the referrer was associated with concordance of diagnosis between the referrer and specialist clinic (

    The IPTA Nashville consensus conference on Post-Transplant lymphoproliferative disorders after solid organ transplantation in children: II-consensus guidelines for prevention

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    The International Pediatric Transplant Association (IPTA) convened an expert consensus conference to assess current evidence and develop recommendations for various aspects of care relating to post-transplant lymphoproliferative disorder after solid organ transplantation in children. In this report from the Prevention Working Group, we reviewed the existing literature regarding immunoprophylaxis and chemoprophylaxis, and pre-emptive strategies. While the group made a strong recommendation for pre-emptive reduction of immunosuppression at the time of EBV DNAemia (low to moderate evidence), no recommendations for use could be made for any prophylactic strategy or alternate pre-emptive strategy, largely due to insufficient or conflicting evidence. Current gaps and future research priorities are highlighted

    The IPTA Nashville Consensus Conference on Post‐Transplant lymphoproliferative disorders after solid organ transplantation in children: III – Consensus guidelines for Epstein‐Barr virus load and other biomarker monitoring

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    The International Pediatric Transplant Association convened an expert consensus conference to assess current evidence and develop recommendations for various aspects of care relating to post-transplant lymphoproliferative disorders after solid organ transplantation in children. In this report from the Viral Load and Biomarker Monitoring Working Group, we reviewed the existing literature regarding the role of Epstein-Barr viral load and other biomarkers in peripheral blood for predicting the development of PTLD, for PTLD diagnosis, and for monitoring of response to treatment. Key recommendations from the group highlighted the strong recommendation for use of the term EBV DNAemia instead of "viremia" to describe EBV DNA levels in peripheral blood as well as concerns with comparison of EBV DNAemia measurement results performed at different institutions even when tests are calibrated using the WHO international standard. The working group concluded that either whole blood or plasma could be used as matrices for EBV DNA measurement; optimal specimen type may be clinical context dependent. Whole blood testing has some advantages for surveillance to inform pre-emptive interventions while plasma testing may be preferred in the setting of clinical symptoms and treatment monitoring. However, EBV DNAemia testing alone was not recommended for PTLD diagnosis. Quantitative EBV DNAemia surveillance to identify patients at risk for PTLD and to inform pre-emptive interventions in patients who are EBV seronegative pre-transplant was recommended. In contrast, with the exception of intestinal transplant recipients or those with recent primary EBV infection prior to SOT, surveillance was not recommended in pediatric SOT recipients EBV seropositive pre-transplant. Implications of viral load kinetic parameters including peak load and viral set point on pre-emptive PTLD prevention monitoring algorithms were discussed. Use of additional markers, including measurements of EBV specific cell mediated immunity was discussed but not recommended though the importance of obtaining additional data from prospective multicenter studies was highlighted as a key research priority
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