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1.
J Hum Evol ; 161: 103075, 2021 12.
Article in English | MEDLINE | ID: mdl-34655947

ABSTRACT

Tam Pà Ling, a cave site in northeastern Laos, has yielded the earliest skeletal evidence of Homo sapiens in mainland Southeast Asia. The reliance of Pleistocene humans in rainforest settings on plant or animal resources is still largely unstudied, mainly due to poor collagen preservation in fossils from tropical environments precluding stable nitrogen isotope analysis, the classical trophic level proxy. However, isotopic ratios of zinc (Zn) in bioapatite constitute a promising proxy to infer trophic and dietary information from fossil vertebrates, even under adverse tropical taphonomic conditions. Here, we analyzed the zinc isotope composition (66Zn/64Zn expressed as δ66Zn value) in the enamel of two teeth of the Late Pleistocene (63-46 ka) H. sapiens individual (TPL1) from Tam Pà Ling, as well as 76 mammal teeth from the same site and the nearby Nam Lot cave. The human individual exhibits relatively low enamel δ66Zn values (+0.24‰) consistent with an omnivorous diet, suggesting a dietary reliance on both plant and animal matter. These findings offer direct evidence of the broad utilization of resources from tropical rainforests by one of the earliest known anatomically modern humans in Southeast Asia.


Subject(s)
Hominidae , Zinc Isotopes , Animals , Asia, Southeastern , Carbon Isotopes/analysis , Fossils , Humans , Nitrogen Isotopes/analysis , Zinc Isotopes/analysis
2.
Eur J Paediatr Neurol ; 49: 120-128, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38492551

ABSTRACT

OBJECTIVES: To observe hyperechoic nodular or punctate white matter lesions (HNPL) in a population of preterm infants using routine cranial ultrasound (cUS), to describe the characteristics of HNPL, and to compare them with punctate white matter lesions (PWML) detected in magnetic resonance imaging (MRI). DESIGN: Retrospective observational single-center cohort study. SETTING: Level 2B neonatal unit in France. PATIENTS: 307 infants born <33 weeks gestation undergoing routine cUS with a total of 961 cUS performed. MAIN OUTCOME MEASURES: Description of lesions (HNPL/PWML): presence or absence, number, size, location, and structural distribution. RESULTS: Among the 307 included infants, 63 (20.5%) had at least one cerebral lesion, with 453 HNPL for 63 infants. HNPL were numerous (more than three in 66.6% of cases), primarily grouped in clusters (76.2%), located near the lateral ventricles (96.8%), and measuring more than 2 mm (79%). HNPL were diagnosed on day 29 on average and persisted until term. Overall, 43 MRI were performed in 307 infants, on average 18.9 days after last cUS, in 21 of those the indication was presence of HPNL on cUS. Of these 21 MRI, 14/21 presented 118 PWML compared to 173 HNPL on cUS. In the remaining MRI (7/21), no PWML were detected compared to 47 HNPL on cUS. CONCLUSIONS: In our population of 307 preterm infants, cUS allowed the diagnosis of HNPL, with a large similarity to PWML in MRI and a better sensitivity. But in the absence of data on inter-observer variability, we cannot exclude overdiagnosis of HNPL.


Subject(s)
Infant, Premature , Magnetic Resonance Imaging , White Matter , Humans , Infant, Newborn , Female , Male , Magnetic Resonance Imaging/methods , White Matter/diagnostic imaging , White Matter/pathology , Retrospective Studies , Leukoencephalopathies/diagnostic imaging , Ultrasonography/methods , Cohort Studies , Brain/diagnostic imaging , Brain/pathology
3.
Nat Commun ; 14(1): 3193, 2023 06 13.
Article in English | MEDLINE | ID: mdl-37311788

ABSTRACT

The timing of the first arrival of Homo sapiens in East Asia from Africa and the degree to which they interbred with or replaced local archaic populations is controversial. Previous discoveries from Tam Pà Ling cave (Laos) identified H. sapiens in Southeast Asia by at least 46 kyr. We report on a recently discovered frontal bone (TPL 6) and tibial fragment (TPL 7) found in the deepest layers of TPL. Bayesian modeling of luminescence dating of sediments and U-series and combined U-series-ESR dating of mammalian teeth reveals a depositional sequence spanning ~86 kyr. TPL 6 confirms the presence of H. sapiens by 70 ± 3 kyr, and TPL 7 extends this range to 77 ± 9 kyr, supporting an early dispersal of H. sapiens into Southeast Asia. Geometric morphometric analyses of TPL 6 suggest descent from a gracile immigrant population rather than evolution from or admixture with local archaic populations.


Subject(s)
Caves , Mammals , Animals , Humans , Laos , Bayes Theorem , Africa , Asia, Eastern
4.
PhytoKeys ; 207: 1-532, 2022.
Article in English | MEDLINE | ID: mdl-36760862

ABSTRACT

Annonaceae is a major pantropical family with 113 genera and about 2550 species. Cameroon is one of the most biodiverse countries in Africa but its flora remains incompletely known. In this volume of the Flora of Cameroon, we describe 166 native taxa representing 163 species in 28 native genera within the family Annonaceae. A total of 22 species (about 13%) are endemic to the country. We provide keys to all native genera, species, and infraspecific taxa. For each species a detailed morphological description and a map of its distribution in Cameroon are provided. Distribution maps and diversity analyses are based on a taxonomically verified database of 2073 collections. Across Africa, Cameroon is a center of diversity for Annonaceae harboring one of the highest numbers of species and genera. For example, Cameroon harbors the highest number of African species for the only pantropical genus of Annonaceae, Xylopia. Annonaceae are found across all 10 administrative regions of Cameroon but diversity is concentrated within the tropical rain forest areas situated in the south and South-West. The areas around Bipindi and Mount Cameroon show the highest levels of diversity, but this is correlated with collection effort. Line drawings and/or photographs accompany most species. One species new to science Uvariopsisetugeana Dagallier & Couvreur sp. nov. is described. We also undertake a number of nomenclatural changes such as lectotypifications, six new synonymies and two new combinations (Uvariaanisotricha (Le Thomas) Couvreur, comb. nov.; Uvariodendronfuscumvar.giganteum (Engl.) Dagallier & Couvreur, comb. nov.).


RésuméLes Annonacées sont une grande famille pantropicale avec 113 genres et 2550 espèces. Le Cameroun est l'un des pays les plus riches en biodiversité d'Afrique mais sa flore reste incomplètement connue. Dans ce volume de la Flore du Cameroun, nous décrivons 166 taxons représentant 163 espèces dans 28 genres au sein de la famille des Annonaceae. Au total, 22 espèces (environ 13%) sont endémiques du pays. Nous fournissons une clé de tous les genres et espèces et des infra-espèces au sein des genres. Pour chaque espèce une description morphologique détaillée et une carte de sa répartition au Cameroun sont fournies. Les cartes de distribution et les analyses de diversité sont basées sur une base de données taxonomiquement vérifiée de 2073 collections. À travers l'Afrique, le Cameroun est un centre de diversité pour les Annonacées abritant l'un des plus grands nombres d'espèces et de genres. Par exemple, le Cameroun abrite le plus grand nombre d'espèces africaines pour le seul genre pantropical d'Annonaceae, Xylopia. Les Annonaceae sont présentent dans les 10 régions du Cameroun, mais la plus grande diversité est concentrée dans les régions abritant la forêt tropicale humide située au sud et au sud-ouest. Les zones autour de Bipindi et du Mont Cameroun présentent les niveaux de diversité les plus élevés, mais cela est corrélé à l'effort de collecte. Des dessins et/ou des photographies accompagnent la plupart des espèces. Une espèce nouvelle pour la science Uvariopsisetugeana Dagalier & Couvreur sp. nov. est décrite. Nous entreprenons également un certain nombre de changements nomenclaturaux tels que des lectotypifications, six nouvelles synonymies et deux nouvelles combinaisons (Uvariaanisotricha (Le Thomas) Couvreur, comb. nov.; Uvariodendronfuscumvar.giganteum (Engl.) Dagalier & Couvreur, comb. nov.).

5.
Nat Commun ; 13(1): 2557, 2022 05 17.
Article in English | MEDLINE | ID: mdl-35581187

ABSTRACT

The Pleistocene presence of the genus Homo in continental Southeast Asia is primarily evidenced by a sparse stone tool record and rare human remains. Here we report a Middle Pleistocene hominin specimen from Laos, with the discovery of a molar from the Tam Ngu Hao 2 (Cobra Cave) limestone cave in the Annamite Mountains. The age of the fossil-bearing breccia ranges between 164-131 kyr, based on the Bayesian modelling of luminescence dating of the sedimentary matrix from which it was recovered, U-series dating of an overlying flowstone, and U-series-ESR dating of associated faunal teeth. Analyses of the internal structure of the molar in tandem with palaeoproteomic analyses of the enamel indicate that the tooth derives from a young, likely female, Homo individual. The close morphological affinities with the Xiahe specimen from China indicate that they belong to the same taxon and that Tam Ngu Hao 2 most likely represents a Denisovan.


Subject(s)
Hominidae , Animals , Bayes Theorem , Female , Fossils , Hominidae/anatomy & histology , Humans , Laos , Molar
6.
Environ Microbiol ; 12(8): 2152-64, 2010 Aug.
Article in English | MEDLINE | ID: mdl-21966910

ABSTRACT

Tropical aquatic legumes of the genus Aeschynomene are unique in that they can be stem-nodulated by photosynthetic bradyrhizobia. Moreover, a recent study demonstrated that two Aeschynomene indica symbionts lack canonical nod genes, thereby raising questions about the distribution of such atypical symbioses among rhizobial-legume interactions. Population structure and genomic diversity were compared among stem-nodulating bradyrhizobia isolated from various Aeschynomene species of Central America and Tropical Africa. Phylogenetic analyses based on the recA gene and whole-genome amplified fragment length polymorphism (AFLP) fingerprints on 110 bacterial strains highlighted that all the photosynthetic strains form a separate cluster among bradyrhizobia, with no obvious structuring according to their geographical or plant origins. Nod-independent symbiosis was present in all sampling areas and seemed to be linked to Aeschynomene host species. However, it was not strictly dependent on photosynthetic ability, as exemplified by a newly identified cluster of strains that lacked canonical nod genes and efficiently stem-nodulated A. indica, but were not photosynthetic. Interestingly, the phenotypic properties of this new cluster of bacteria were reflected by their phylogenetical position, as being intermediate in distance between classical root-nodulatingBradyrhizobium spp. and photosynthetic ones. This result opens new prospects about stem-nodulating bradyrhizobial evolution.


Subject(s)
Bradyrhizobiaceae/classification , Fabaceae/microbiology , Phylogeny , Plant Stems/microbiology , Symbiosis , Africa , Amplified Fragment Length Polymorphism Analysis , Biological Evolution , Bradyrhizobiaceae/genetics , Bradyrhizobiaceae/physiology , Central America , DNA, Bacterial/genetics , Genome, Bacterial , Molecular Sequence Data , Phenotype , Photosynthesis
7.
Joint Bone Spine ; 70(6): 503-8, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14667563

ABSTRACT

OBJECTIVE: The purpose was to analyze magnetic resonance imaging (MRI) abnormalities in reflex sympathetic dystrophy syndrome (RSDS) of the foot, with the goal of helping to meet the difficult diagnostic challenges raised by this condition. METHODS: Retrospective study of 20 patients with RSDS of the foot, 15 at the warm phase and five at the dystrophic phase. RESULTS: Of the 15 patients at the warm phase, seven had evidence of bone edema (low signal on T1-weighted images and high signal on T2, T2 STIR, and fat saturation images) and five had occult fractures (linear band of low signal on T1 and T2 weighted images with no enhancement after contrast injection). Other abnormalities included soft tissue changes in three patients, joint effusion in five, and synovial hypertrophy in one. Of the five patients at the dystrophic phase, one had a fracture with a joint effusion, one had isolated joint edema, and three had normal MRI findings. CONCLUSION: Bone marrow edema is inconsistent at the warm phase of RSDS and is never present at the dystrophic phase. Thus, absence of bone edema does not rule out RSDS. Fractures may be visible by MRI in one-third of patients with RSDS and no clinical or plain radiography evidence of fracturing.


Subject(s)
Foot Diseases/diagnosis , Magnetic Resonance Imaging , Reflex Sympathetic Dystrophy/diagnosis , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Retrospective Studies
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