40 research outputs found
Unique Case of Anca-Negative Pauci-Immune Necrotizing Glomerulonephritis With Diffuse Alveolar Hemorrhage, Potentially Associated With Midostaurin
We present a 61-year-old male with FLT3-mutated acute myeloid leukemia treated with midostaurin who developed acute kidney injury requiring hemodialysis and pulmonary renal syndrome. Antibodies to proteinase-3, myeloperoxidase, and glomerular basement membrane were negative. Renal biopsy confirmed acute pauci-immune focal necrotizing glomerulonephritis (GN) with fibrin crescents indicating rapidly progressing glomerulonephritis. He improved with pulse methylprednisolone, intravenous cyclophosphamide, and plasma exchange with resolution of hemoptysis. This case highlights the importance of prompt renal biopsy to guide early initiation of life-saving therapies. To our knowledge, this is the first reported case of ANCA-negative pauci-immune necrotizing GN likely secondary to midostaurin
Analyse de sensibilitĂ© Ă des changements morphologiques du complexe de lâĂ©pauleâŻ: application aux gestes de percussion au cours de dĂ©bitage oldowayen
Si la fabrication et lâutilisation dâoutils lithiques ont incontestablement jouĂ© un rĂŽle dĂ©terminant dans lâĂ©volution des hominines, lâimpact de tels comportements sur leur morphologie semble moins faire consensus. Toutefois, il semble que lâarchitecture et les proportions du complexe de lâĂ©paule chez les premiers reprĂ©sentants du genre Homo aient pu avoir Ă©tĂ© contraintes par ces comportements. Afin de discuter des potentiels avantages adaptatifs de ces traits morphologiques dans le cadre de ..
Homo luzonensisâŻ: principales caractĂ©ristiques et implications pour lâhistoire Ă©volutionnaire du genre
La nouvelle espĂšce Homo luzonensis a Ă©tĂ© dĂ©crite en 2019 Ă partir dâun assemblage constituĂ© de treize Ă©lĂ©ments fossiles dĂ©couverts dans la grotte de Callao (Ăźle de Luzon, Philippines) en 2007, 2011 et 2015. La datation directe de deux de ces fossiles par les sĂ©ries de lâuranium indique des Ăąges minimums respectifs de 50 000 et 67 000 ans. Dans cette prĂ©sentation, nous montrons que ces spĂ©cimens prĂ©sentent une combinaison de caractĂ©ristiques morphologiques primitives (i.e. ressemblant Ă Austra..
Relationship between foramen magnum position and locomotion in extant and extinct hominoids
International audienceFrom the Miocene Sahelanthropus tchadensis to Pleistocene Homo sapiens, hominins are characterized by a derived anterior position of the foramen magnum relative to basicranial structures. It has been previously suggested that the anterior position of the foramen magnum in hominins is related to bipedal locomotor behavior. Yet, the functional relationship between foramen magnum position and bipedal locomotion remains unclear. Recent studies, using ratios based on cranial linear measurements, have found a link between the anterior position of the foramen magnum and bipedalism in several mammalian clades: marsupials, rodents, and primates. In the present study, we compute these ratios in a sample including a more comprehensive dataset of extant hominoids and fossil hominins. First, we verify if the values of ratios can distinguish extant humans from apes. Then, we test whether extinct hominins can be distinguished from non-bipedal extant hominoids. Finally, we assess if the studied ratios are effective predictors of bipedal behavior by testing if they mainly relate to variation in foramen magnum position rather than changes in other cranial structures. Our results confirm that the ratios discriminate between extant bipeds and non-bipeds. However, the only ratio clearly discriminating between fossil hominins and other extant apes is that which only includes basicranial structures. We show that a large proportion of the interspecific variation in the other ratios relates to changes in facial, rather than basicranial, structures. In this context, we advocate the use of measurements based only on basicranial structures when assessing the relationship between foramen magnum position and bipedalism in future studies
Proconsul heseloni distal radial and ulnar epiphyses from the Kaswanga Primate Site, Rusinga Island, Kenya.
International audienceOnly two distal epiphyses of a radius and ulna are consensually attributed to the holotype skeleton of Proconsul heseloni, KNM-RU 2036. Here, we describe seven adult and immature distal antebrachial (radial and ulnar) epiphyses from two other individuals of P. heseloni from the Lower Miocene deposits of the Kaswanga Primate Site (KPS), Rusinga Island, Kenya. Because KNM-RU 2036 and KNM-KPS individuals III and VIII are conspecific and penecontemporaneous, their comparison provides the opportunity i) to characterize, for the first time, the morphological variation of the distal radioulnar joint in a Miocene ape, P. heseloni, and ii) to investigate the functional and evolutionary implications. Our results show that the distal antebrachial epiphyses of KNM-KPS III and VIII correspond to stages of bone maturation that are more advanced than those of KNM-RU 2036 (larger articulations and sharper articular borders and ligament attachments that are more developed). Accordingly, functional interpretations based solely on the skeleton of KNM-RU 2036 have involved an underestimation of the forearm rotation abilities of P. heseloni. In particular, the KPS fossils do not exhibit the primitive morphology of distal radioulnar syndesmosis, as those of KNM-RU 2036 and most nonhominoid primates, but rather the morphology of an incipient diarthrosis (as in extant lorisines and hominoids). The distal radioulnar diarthrosis permits more mobility and maintenance of the wrist during repeated and slow rotation of the forearms, which facilitates any form of quadrupedal locomotion on discontinuous and variably oriented supports. By providing the oldest evidence of a distal radioulnar joint in an early Miocene hominoid, the main conclusions of this study are consistent with the role of cautious climbing as a prerequisite step for the emergence of positional adaptations in apes
Primates non humains : bilan des recherches et perspectives anthropobiologiques
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<i>Australopithecus afarensis</i> Ă©tait-il capable de fabriquer les outils du Lomekwien ? DĂ©veloppement dâune simulation biomĂ©canique des capacitĂ©s de force de prĂ©hension dâhominines fossiles et nouvelles perspectives sur lâimplication du cinquiĂšme doigt
Alors quâaucun consensus ne permet dâĂ©tablir comment ou quand les caractĂšres morphologiques de la main humaine ont Ă©mergĂ© au sein du registre fossile, les rĂ©centes dĂ©couvertes des outils de Lomekwi 3 (3,3 Ma) suggĂšrent que des hominines anciens Ă©taient capables dâutiliser des prises manuelles puissantes pour tailler et manipuler des blocs de grande taille. Afin dâĂ©valuer les aptitudes prĂ©hensiles dâun hominine contemporain, une modĂ©lisation musculo-squelettique de la main dâAustralopithecus afarensis a Ă©tĂ© dĂ©veloppĂ©e. Une Ă©tude de sensibilitĂ© a montrĂ© la faible influence des paramĂštres musculaires (e.g., PCSA) nĂ©cessairement extraits dâespĂšces analogues actuelles au regard des paramĂštres cinĂ©matiques de lâarticulation carpo-mĂ©tacarpienne 5 et dĂ©montrent ainsi la pertinence de cette approche pour lâĂ©tude des taxons fossiles. Nos rĂ©sultats suggĂšrent Ă©galement une capacitĂ© limitĂ©e de la main dâA. afarensis Ă mettre en contact la pulpe du 5e rayon et la surface dâun objet volumineux. Ainsi, A. afarensis aurait disposĂ© dâaptitudes limitĂ©es Ă produire des forces suffisantes pour la manufacture des outils en pierre du Lomekwien.While no consensus allows explaining how and when human-like traits arose in fossil hominin hands, the recent discoveries of the Lomekwian stone tools (3.3 Ma) support the view that early hominins were able to use forceful grips in order to manipulate large-sized blocks for pounding activities. Then, assessing gripping abilities of contemporaneous hominin, i.e. Australopithecus afarensis , is necessary, particularly with regards to its unusual 5th ray morphology that has been deemed crucial to ensure forceful grips. Here, we present a musculoskeletal simulation based on the A. afarensis hand morphology that includes an original 5th carpometacarpal joint. Our first results suggest a limited influence of muscle parameters (e.g., PCSA) and support the value of simulations for studying extinct taxa even in absence of soft-tissue data. Given the inability for the pulp of the 5th ray to face the surface of a large-sized object, the A. afarensis hand would have had limited possibility to exert sufficient force to make the Lomekwian stone tools.</p
Australopithecus afarensis Ă©tait-il capable de fabriquer les outils du Lomekwien ? DĂ©veloppement dâune simulation biomĂ©canique des capacitĂ©s de force de prĂ©hension dâhominines fossiles et nouvelles perspectives sur lâimplication du cinquiĂšme doigt
International audienceWhile no consensus allows explaining how and when human-like traits arose in fossil hominin hands, the recent discoveries of the Lomekwian stone tools (3.3 Ma) support the view that early hominins were able to use forceful grips in order to manipulate large-sized blocks for pounding activities. Then, assessing gripping abilities of contemporaneous hominin, i.e. Australopithecus afarensis, is necessary, particularly with regards to its unusual 5th ray morphology that has been deemed crucial to ensure forceful grips. Here, we present a musculoskeletal simulation based on the A. afarensis hand morphology that includes an original 5th carpometacarpal joint. Our first results suggest a limited influence of muscle parameters (e.g., PCSA) and support the value of simulations for studying extinct taxa even in absence of soft-tissue data. Given the inability for the pulp of the 5th ray to face the surface of a large-sized object, the A. afarensis hand would have had limited possibility to exert sufficient force to make the Lomekwian stone tools.Alors quâaucun consensus ne permet dâĂ©tablir comment ou quand les caractĂšres morphologiques de la main humaine ont Ă©mergĂ© au sein du registre fossile, les rĂ©centes dĂ©couvertes des outils de Lomekwi 3 (3,3 Ma) suggĂšrent que des hominines anciens Ă©taient capables dâutiliser des prises manuelles puissantes pour tailler et manipuler des blocs de grande taille. Afin dâĂ©valuer les aptitudes prĂ©hensiles dâun hominine contemporain, une modĂ©lisation musculo-squelettique de la main dâAustralopithecus afarensis a Ă©tĂ© dĂ©veloppĂ©e. Une Ă©tude de sensibilitĂ© a montrĂ© la faible influence des paramĂštres musculaires (e.g., PCSA) nĂ©cessairement extraits dâespĂšces analogues actuelles au regard des paramĂštres cinĂ©matiques de lâarticulation carpo-mĂ©tacarpienne 5 et dĂ©montrent ainsi la pertinence de cette approche pour lâĂ©tude des taxons fossiles. Nos rĂ©sultats suggĂšrent Ă©galement une capacitĂ© limitĂ©e de la main dâA. afarensis Ă mettre en contact la pulpe du 5e rayon et la surface dâun objet volumineux. Ainsi, A. afarensis aurait disposĂ© dâaptitudes limitĂ©es Ă produire des forces suffisantes pour la manufacture des outils en pierre du Lomekwien
Le complexe articulaire du poignet des Hominoidea miocenes et plio-pleistocenes africains (approche comparative anatomo-fonctionnelle et morphométrique)
Pour prĂ©ciser les conditions d Ă©mergence de la bipĂ©die, une caractĂ©risation du rĂŽle du poignet dans la pratique de postures manuelles chez les ancĂȘtres potentiels des Hominoidea actuels a Ă©tĂ© rĂ©alisĂ©e. Dans ce but, l analyse morphologique de 115 fossiles originaux (27 inĂ©dits) a Ă©tĂ© complĂ©tĂ©e par une double approche anatomo-fonctionnelle et morphomĂ©trique gĂ©omĂ©trique. Les rĂ©sultats montrent qu au MiocĂšne, une grande diversitĂ© de palmigradies devaient ĂȘtre pratiquĂ©es, essentiellement arboricoles (Proconsul heseloni, Nacholapithecus, Limnopithecus, Rangwapithecus, Kalepithecus, Dendropithecus, Turkanapithecus), mais aussi en partie terrestres (Proconsul nyanzae, Afropithecus). L usage d une digitigradie/knuckle-walking est mĂȘme envisagĂ©e (Equatorius). Seuls Proconsul, Nacholapithecus et Equatorius sont rapprochĂ©s des Hominoidea actuels. Au Plio-PlĂ©istocĂšne, Australopithecus et Paranthropus, bipĂšdes, semblent avoir conservĂ©s des aptitudes au grimper.To clarify the conditions for the emergence of bipedalism, a characterization of the role of the wrist in hand postures among putative ancestors of Hominoidea is proposed. To this end, the morphological analysis of 115 original fossils (27 unpublished) was complemented by both an anatomo-functional and a geometric morphometric approach. The results show that during the Miocene, a wide variety of palmigradies was practiced, mainly arboreal (Proconsul heseloni, Nacholapithecus, Limnopithecus, Rangwapithecus, Kalepithecus, Dendropithecus, Turkanapithecus), but partly terrestrial also (Proconsul nyanzae, Afropithecus). The use of a digitigradie / knuckle-walking hand posture is even considered (Equatorius). Only Proconsul, Nacholapithecus and Equatorius show affinities to extant Hominoidea. In the Plio-Pleistocene, Australopithecus and Paranthropus, both bipedal hominoids, seem to have retained the ability to climb.PARIS-Museum Hist.Naturelle (751052304) / SudocSudocFranceF
Fossil hominins, quadrupedal primates and the origin of human bipedalism: a 3D geometric morphometric analysis of the Primate hamate
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