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1.
Sci Adv ; 8(6): eabj9496, 2022 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35138885

RESUMEN

Determining the extent of overlap between modern humans and other hominins in Eurasia, such as Neanderthals and Denisovans, is fundamental to understanding the nature of their interactions and what led to the disappearance of archaic hominins. Apart from a possible sporadic pulse recorded in Greece during the Middle Pleistocene, the first settlements of modern humans in Europe have been constrained to ~45,000 to 43,000 years ago. Here, we report hominin fossils from Grotte Mandrin in France that reveal the earliest known presence of modern humans in Europe between 56,800 and 51,700 years ago. This early modern human incursion in the Rhône Valley is associated with technologies unknown in any industry of that age outside Africa or the Levant. Mandrin documents the first alternating occupation of Neanderthals and modern humans, with a modern human fossil and associated Neronian lithic industry found stratigraphically between layers containing Neanderthal remains associated with Mousterian industries.

2.
Int Orthop ; 45(5): 1257-1261, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33547484

RESUMEN

PURPOSE: Sickle cell disease is often associated with osteonecrosis of the humeral head with a risk of progression to humeral head collapse. The aim of this study was to evaluate the clinical outcome and the effect on the necrosis evolution of humeral head core decompression with autologous bone marrow aspirate injection in these patients. METHODS: Forty shoulders in 23 patients were treated with core decompression with autologous concentrated iliac crest bone marrow aspirate injection. Patients were followed for a minimum of two  years (limits from 2 to 10 years). Functional outcomes metrics included the simple shoulder test (STT) and subjective shoulder value (SSV) as well as assessment of radiographic progression of disease. RESULTS: Shoulder function improved significantly at final follow-up. The STT improved by 2.9 points (p = 0.001) and the SVV improved by 15 % (p = 0.001). However, based on radiologic features, the intervention did not halt the radiographic progression of disease nor did it result in healing of the lesion. The benefits were mainly clinical with diminished pain and functional improvement. CONCLUSION: Improvement in shoulder function was observed following core decompression and bone marrow aspirate injection in patients with sickle cell disease and early humeral head necrosis stages. The procedure should not be considered for grade 3 or greater disease and for asymptomatic cases whatever the grade. Given the lack of radiographic improvement observed in this study, further study in the context of prospective controlled trials should be undertaken before this intervention can be widely recommended.


Asunto(s)
Anemia de Células Falciformes , Necrosis de la Cabeza Femoral , Osteonecrosis , Adulto , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/terapia , Médula Ósea , Descompresión Quirúrgica , Necrosis de la Cabeza Femoral/cirugía , Humanos , Cabeza Humeral/diagnóstico por imagen , Cabeza Humeral/cirugía , Osteonecrosis/cirugía , Osteonecrosis/terapia , Estudios Prospectivos , Trasplante Autólogo , Resultado del Tratamiento
3.
Orthop Traumatol Surg Res ; 106(5): 877-880, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32624378

RESUMEN

Percutaneous iliosacral screw fixation is an essential osteosynthesis technique for pelvic fractures and requires precise imaging tools to assist correct screw placement. 3D imaging coupled to navigation has significantly improved this technique. Several possibilities exist, depending on the instrument set used, with varying degrees of difficulty and very variable risk of error. The techniques traditionally described use a guide to navigate a drill bit, where a one-degree difference in trajectory can alter screw tip placement by several millimeters. The present article proposes a standardization of the procedure by using navigated pedicular screw instruments that have the advantage of navigating the instrument itself and not a projection. In a series of 90 screws implanted in 62 patients using this technique, only one path had to be repeated in the light of intraoperative control. No improperly positioned screws were found on postoperative control.


Asunto(s)
Fracturas Óseas , Huesos Pélvicos , Cirugía Asistida por Computador , Tornillos Óseos , Fijación Interna de Fracturas , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/cirugía , Humanos , Ilion/diagnóstico por imagen , Ilion/cirugía , Huesos Pélvicos/diagnóstico por imagen , Huesos Pélvicos/cirugía , Sacro/diagnóstico por imagen , Sacro/cirugía
4.
Orthop Traumatol Surg Res ; 106(3): 475-479, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32253135

RESUMEN

INTRODUCTION: Collagen scaffolds are a good surgical option for covering large focal osteochondral defects in the knee. In the recent literature there is a wide range of patient profiles and chondral defect treatments (chondral and osteochondral defects, associated procedures, etc.). The aim of the present study was to evaluate clinical and imaging outcomes with collagen scaffolds and to assess any correlation between medium-term clinical outcome and MRI features. The hypothesis was that there is no correlation between clinical outcome and MRI after 2 years postoperatively. MATERIAL AND METHODS: A single-center retrospective observational study included all patients receiving a MaioRegen® scaffold for large painful focal osteochondral defect of the femoral condyle. There were 17 patients, with a mean age of 28±9 years. Defect locations comprised 12 medial femoral condyles, 4 lateral femoral condyles and 1 lateral tibial plateau. Mean defect area was 4.5±1.4cm2. All patients were evaluated clinically and on KOOS and objective and subjective IKDC scales, with MRI at last follow-up. RESULTS: At a mean follow-up of 46±17 months, mean subjective IKDC was 67.8±23; KOOS scores were: symptoms, 78±22; pain, 78±23; function, 85±20; sports, 66±27; and activities of daily living, 59±25. MRI MOCART score revealed incomplete scaffold healing in 21.4% of cases, with variable signal intensity within regenerated tissue. Functional scores did not correlate with reconstruction aspect on MRI. DISCUSSION/CONCLUSION: 3D collagen scaffolds yield good medium-term clinical outcomes in large osteochondral defects of the knee. There is, however, a discrepancy between MRI features of the recipient site and objective and subjective clinical scores. These scaffolds may be a good option for treating large focal osteochondral defects in knees of young patients, but MRI does not provide satisfactory medium-term assessment.


Asunto(s)
Actividades Cotidianas , Cartílago Articular , Huesos , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/cirugía , Colágeno , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Imagen por Resonancia Magnética , Estudios Prospectivos , Andamios del Tejido , Adulto Joven
5.
Int Orthop ; 42(7): 1739-1745, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29796764

RESUMEN

PURPOSE: Despite multiple possible treatments, the risk of collapse remains the main problem of osteonecrosis. Heart failure (HF). In an effort to address the reverse this issue, curative strategies with regenerative medicine are increasingly being considered. The aim of this technology is to halt or reverse progression of the disease to collapse. MATERIAL AND METHODS: The pioneering report by Hernigou published in 2002 was the first pilot study suggesting that injection of bone marrow stem cells was a safe approach able to improve osteonecrosis in patients with early stages. Since then, an impressive number of studies and trials employing unselected BM-derived cells (1000 the last 2 years) showed that delivery of those cells to the site of osteonecrosis during core decompression was somehow able to ameliorate the patient with osteonecrosis. In order to translate the promise of this cell therapy into better clinical benefit, many questions need to be addressed. In this review, we therefore analyzed current clinical experience of the literature and our experience of 4000 cases to address these questions and particularly the number of cells that should be injected. RESULTS: After almost 20 years of clinical research in this field, we are still far from having drawn conclusions on the number of cells we should inject in regenerating hip osteonecrosis. Findings are difficult to interpret due to heterogeneity of causes of osteonecrosis, as well as differences in the cells count, sample quality, and stages of osteonecrosis. The authors address specific issues, as cell quality, cell numbers, volume of osteonecrosis, concentration of cells, and ex vivo expansion. Bone marrow mesenchymal stem cells are supposed to be "functionally competent," but are collected from the bon, marrow of patients with diseases and risk factors of osteonecrosis. The recipient organ (bone osteonecrosis) is a tissue where several alterations have already occurred. These questions are addressed in this review. CONCLUSION: In this review, we analyzed current clinical experience regarding cell therapy and address issues that should be a guide for future cell-based therapeutic application in osteonecrosis.


Asunto(s)
Necrosis de la Cabeza Femoral/terapia , Trasplante de Células Madre Mesenquimatosas/métodos , Descompresión Quirúrgica/métodos , Progresión de la Enfermedad , Articulación de la Cadera/cirugía , Humanos , Trasplante Autólogo
6.
Science ; 356(6340): 841-844, 2017 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-28546210

RESUMEN

Plate-boundary fault rupture during the 2004 Sumatra-Andaman subduction earthquake extended closer to the trench than expected, increasing earthquake and tsunami size. International Ocean Discovery Program Expedition 362 sampled incoming sediments offshore northern Sumatra, revealing recent release of fresh water within the deep sediments. Thermal modeling links this freshening to amorphous silica dehydration driven by rapid burial-induced temperature increases in the past 9 million years. Complete dehydration of silicates is expected before plate subduction, contrasting with prevailing models for subduction seismogenesis calling for fluid production during subduction. Shallow slip offshore Sumatra appears driven by diagenetic strengthening of deeply buried fault-forming sediments, contrasting with weakening proposed for the shallow Tohoku-Oki 2011 rupture, but our results are applicable to other thickly sedimented subduction zones including those with limited earthquake records.

7.
Nature ; 505(7482): 204-7, 2014 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-24291793

RESUMEN

Three-quarters of the oceanic crust formed at fast-spreading ridges is composed of plutonic rocks whose mineral assemblages, textures and compositions record the history of melt transport and crystallization between the mantle and the sea floor. Despite the importance of these rocks, sampling them in situ is extremely challenging owing to the overlying dykes and lavas. This means that models for understanding the formation of the lower crust are based largely on geophysical studies and ancient analogues (ophiolites) that did not form at typical mid-ocean ridges. Here we describe cored intervals of primitive, modally layered gabbroic rocks from the lower plutonic crust formed at a fast-spreading ridge, sampled by the Integrated Ocean Drilling Program at the Hess Deep rift. Centimetre-scale, modally layered rocks, some of which have a strong layering-parallel foliation, confirm a long-held belief that such rocks are a key constituent of the lower oceanic crust formed at fast-spreading ridges. Geochemical analysis of these primitive lower plutonic rocks--in combination with previous geochemical data for shallow-level plutonic rocks, sheeted dykes and lavas--provides the most completely constrained estimate of the bulk composition of fast-spreading oceanic crust so far. Simple crystallization models using this bulk crustal composition as the parental melt accurately predict the bulk composition of both the lavas and the plutonic rocks. However, the recovered plutonic rocks show early crystallization of orthopyroxene, which is not predicted by current models of melt extraction from the mantle and mid-ocean-ridge basalt differentiation. The simplest explanation of this observation is that compositionally diverse melts are extracted from the mantle and partly crystallize before mixing to produce the more homogeneous magmas that erupt.

8.
Science ; 306(5705): 2216-21, 2004 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-15618510

RESUMEN

Diverse microbial communities and numerous energy-yielding activities occur in deeply buried sediments of the eastern Pacific Ocean. Distributions of metabolic activities often deviate from the standard model. Rates of activities, cell concentrations, and populations of cultured bacteria vary consistently from one subseafloor environment to another. Net rates of major activities principally rely on electron acceptors and electron donors from the photosynthetic surface world. At open-ocean sites, nitrate and oxygen are supplied to the deepest sedimentary communities through the underlying basaltic aquifer. In turn, these sedimentary communities may supply dissolved electron donors and nutrients to the underlying crustal biosphere.


Asunto(s)
Bacterias/metabolismo , Ecosistema , Sedimentos Geológicos/microbiología , Bacterias/crecimiento & desarrollo , Bacterias/aislamiento & purificación , Carbono/metabolismo , Recuento de Colonia Microbiana , Transporte de Electrón , Hierro/metabolismo , Manganeso/metabolismo , Metano/metabolismo , Nitratos/metabolismo , Oxidantes/metabolismo , Oxidación-Reducción , Océano Pacífico , Perú , Fotosíntesis , Agua de Mar/química , Sulfatos/metabolismo , Termodinámica
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