21 research outputs found
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New evidence suggesting a dissociated etiology for cribra orbitalia and porotic hyperostosis
Objectives:
Porotic hyperostosis, characterized by porotic lesions on the cranial vault, and , a localized appearance of porotic lesions on the roof of the orbits, are relatively common osteological conditions. Their etiology has been the focus of several studies, and an association with anemia has long been suggested. Anemia often causes bone marrow hypertrophy or hyperplasia, leading to the expansion in trabecular or cranial diploic bone as a result of increased hematopoiesis. Hypertrophy and/or hyperplasia is often coupled with a disruption of the remodeling process of outer cortical bone, cranially and/or post-cranially, leading to the externally visible porotic lesions reported in osteological remains. In this paper, we investigate whether individuals with cribra orbitalia have increased thickness of the diploë, the common morphological direct effect of increased hematopoiesis, and thus test the relationship between the two conditions, as well as explore the type of anemia that underlie it.
Methods:
An analysis of medical CT scans of a worldwide sample of 98 complete, young to middle-aged adult dry skulls from the Duckworth Collection was conducted on male and female cribrotic individuals (n= 23) and non-cribrotic individuals (n= 75), all of whom lacked any evidence of porotic lesions on the vault. Measurements of total and partial cranial thickness were obtained by virtual landmark placement, using the Amira 5.4 software; all analyses were conducted in IBM SPSS 21.
Results:
Cribriotic individuals have significantly thinner diploic bone and thicker outer and inner tables than non-cribriotic individuals, contrary to the expected diploic expansion that would result from anemic conditions associated to bone marrow hypertrophy or hyperplasia. Additionally, individuals without cribra orbitalia and those with the condition have distinctive cranial thickness at particular locations across the skull and the severity to which cribra orbitalia is expressed also differentiates between those with mild and those with a moderate to severe form of the condition.
Conclusions:
Our results suggest a complex pattern of causality in relation to the pathologies that may lead to the formation of porotic lesions on the vault and the roof of the orbits. A form of anemia may be behind the osteological changes observed in porotic hyperostosis and cribra orbitalia, but it is unlikely to be the same type of anemic condition that underlies both types of osteological lesions. We suggest that cribra orbitalia may be associated to anemias that lead to diploic bone hypocellularity and hypoplasia, such as those caused by anemia of chronic disease and, to a lesser extent, of renal failure, aplastic anemia, protein deficiency and anemia of endocrine disorders, and not those that lead to bone marrow hypercellularity and hyperplasia and potential porotic hyperostosis. This leads us to the conclusion that the terms porotic hyperostosis and cribra orbitalia should be used to reflect different underlying conditions.Duckworth Collection; Advanced Investigator Award from the European Research Council, ERC No. 295907, to MM
Newly-discovered Neanderthal remains from Shanidar Cave, Iraqi Kurdistan, and their attribution to Shanidar 5
The Neanderthal remains from Shanidar Cave, excavated between 1951 and 1960, have played a central role in debates concerning diverse aspects of Neanderthal morphology and behavior. In 2015 and 2016, renewed excavations at the site uncovered hominin remains from the immediate area where the partial skeleton of Shanidar 5 was found in 1960. Shanidar 5 was a robust adult male estimated to have been aged over 40 years at the time of death. Comparisons of photographs from the previous and recent excavations indicate that the old and new remains were directly adjacent to one another, while the disturbed arrangement and partial crushing of the new fossils is consistent with descriptions and photographs of the older discoveries. The newly discovered bones include fragments of several vertebrae, a left hamate, part of the proximal left femur, a heavily crushed partial pelvis, and the distal half of the right tibia and fibula and associated talus and navicular. All these elements were previously missing from Shanidar 5, and morphological and metric data are consistent with the new elements belonging to this individual. A newly discovered partial left pubic symphysis indicates an age at death of 40–50 years, also consistent with the age of Shanidar 5 estimated previously. Thus, the combined evidence strongly suggests that the new finds can be attributed to Shanidar 5. Ongoing analyses of associated samples, including for sediment morphology, palynology, and dating, will therefore offer new evidence as to how this individual was deposited in the cave and permit new analyses of the skeleton itself and broader discussion of Neanderthal morphology and variation.This work was supported by the Leverhulme Trust (RPG-2013-105, held by GB). EP is supported by the Leverhulme (ECF-2015- 520) and Isaac Newton Trusts. MML's and FC's research is supported by the European Research Council (ERC #295907)
A new deep branch of eurasian mtDNA macrohaplogroup M reveals additional complexity regarding the settlement of Madagascar.
BACKGROUND: Current models propose that mitochondrial DNA macrohaplogroups M and N evolved from haplogroup L3 soon after modern humans left Africa. Increasingly, however, analysis of isolated populations is filling in the details of, and in some cases challenging, aspects of this general model. RESULTS: Here, we present the first comprehensive study of three such isolated populations from Madagascar: the Mikea hunter-gatherers, the neighbouring Vezo fishermen, and the Merina central highlanders (n = 266). Complete mitochondrial DNA genome sequences reveal several unresolved lineages, and a new, deep branch of the out-of-Africa founder clade M has been identified. This new haplogroup, M23, has a limited global distribution, and is restricted to Madagascar and a limited range of African and Southwest Asian groups. CONCLUSIONS: The geographic distribution, phylogenetic placement and molecular age of M23 suggest that the colonization of Madagascar was more complex than previously thought.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
Ancient genomes show social and reproductive behavior of early Upper Palaeolithic foragers
Present-day hunter-gatherers (HGs) live in multilevel social groups essential to sustain a population structure characterized by limited levels of within-band relatedness and inbreeding. When these wider social networks evolved among HGs is unknown. Here, we investigate whether the contemporary HG strategy was already present in the Upper Paleolithic (UP), using complete genome sequences from Sunghir, a site dated to ~34 thousand years BP (kya) containing multiple anatomically modern human (AMH) individuals. Wedemonstrate that individuals at Sunghir derive from a population of small effective size, with limited kinship and levels of inbreeding similar to HG populations. Our findings suggest that UP social organization was similar to that of living HGs, with limited relatedness within residential groups embedded in a larger mating network
The population history of northeastern Siberia since the Pleistocene
FGW – Publications without University Leiden contractDescriptive and Comparative Linguistic
Origine d'Homo Sapiens : un morphotype ancestral pour l'homme moderne
Résumé de la communication présentée au Colloque annuel de la société d'anthropologie de Paris- 1838e Réunion scientifique 23-25 janvier 2013 Paris, dans Bulletins et mémoires de la Société d'Anthropologie de Paris, vol.25 I Supplement
Ancient mitochondrial DNA from Malaysian hair samples: Some indications of Southeast Asian population movements
International audienceThe late Pleistocene and early Holocene population history of Southeast Asia is not well-known. Our study provides new data on mitochondrial DNA (mtDNA) lineages of the aboriginal inhabitants of the Malay Peninsula, and through an extensive comparison to the known mtDNA diversity in Southeast and East Asia, provides some new insights into the origins and historical geography of certain mtDNA lineages in the region. We extracted DNA from hair samples (dating back 100 years) preserved in the Duckworth Collection and belonging to two Peninsular Malaysian individuals identified as "Negrito." Ancient DNA was analyzed by sequencing hypervariable region I (HVS-I) of the mtDNA control region and the mtDNA region V length polymorphism. The results show that the maternal lineages of these individuals belong to a recently defined haplogroup B sub-branch called B4c2. A comparison of mitochondrial haplotypes and haplogroups with those of 10,349 East Asian individuals indicates their very restricted geographical distribution (southwestern China, Southeast Asia Peninsula, and Indonesia). Recalculation of the B4c2 age across all of East Asia ( approximately 13,000 years) and in different subregions/populations suggests its rapid diffusion in Southeast Asia between the end of the Last Glacial Maximum and the Neolithic expansion of the Holocene
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A new deep branch of eurasian mtDNA macrohaplogroup M reveals additional complexity regarding the settlement of Madagascar
Abstract Background Current models propose that mitochondrial DNA macrohaplogroups M and N evolved from haplogroup L3 soon after modern humans left Africa. Increasingly, however, analysis of isolated populations is filling in the details of, and in some cases challenging, aspects of this general model. Results Here, we present the first comprehensive study of three such isolated populations from Madagascar: the Mikea hunter-gatherers, the neighbouring Vezo fishermen, and the Merina central highlanders (n = 266). Complete mitochondrial DNA genome sequences reveal several unresolved lineages, and a new, deep branch of the out-of-Africa founder clade M has been identified. This new haplogroup, M23, has a limited global distribution, and is restricted to Madagascar and a limited range of African and Southwest Asian groups. Conclusions The geographic distribution, phylogenetic placement and molecular age of M23 suggest that the colonization of Madagascar was more complex than previously thought.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are