Découverte d’un nouvel hominidé à Dmanissi (Transcaucasie,Géorgie)

Four human remains: one mandible, two skulls and one metatarsus were discovered between 1991 and 1999 at the open-air site of Dmanisi, Georgia, in a precise stratigraphic, palaeontological and archaeological context, in volcanic ashes dated to 1.81 ± 0.05 Ma. The first studies of these fossils enable the authors to compare them with the morphology of archaic African Homo erectus, ascribed to Homo ergaster, and to ascertain hominid presence at the gates of Europe 300 000 years earlier than the classical scenario forecasted. In September 2000, the discovery of a second more complete and robust mandible D 2600 presents a threefold interest: palaeontological, functional and pathological. A comparison with Homo habilis and Homo erectus leads to the recognition of a new Homo species: H. georgicus sp. nov. The morphofunctional characteristics and the antiquity of H. georgicus characterise the root of a long Eurasian line.     

Spectrométrie de masse et hémocultures: un nouvel outil de diagnostic immédiat

Delay in identification of microorganisms hamper the prompt initiation of adequate empirical antibiotic therapy of bacteremia. MALDI-TOF-MS allows identification of microorganisms directly from colonies within minutes. Identification of microorganisms responsible for bacteremia can be made directly from blood culture bottles. Many different protocols have been published, all based on the separation of microorganisms from erythrocytes and blood culture broth that alter the quality of spectra. Correct identifications were obtained for most of the procedures used in at least 80% of cases, within 20 to 60 min once the blood culture is detected positive. MALDI-TOF-MS, by far the fastest identification technique, offers a significant breakthrough in the management of bacteremia.     

La métabolomique: un nouvel outil pour la recherche translationnelle en cancérologie

Development and validation of novel diagnostic and prognostic tools for cancer patients are a clinically unmet need, especially to help predicting survival or treatment response and toxicity. Metabolomics provides a dynamic portrait of the metabolic state of a tumour in response to pathophysiological stimuli (such as tumour growth or tumour shrinkage) and helps us understand the molecular mechanism sustaining these phenomena. Recent literature presented encouraging data on potential applications of metabolomics in translational research. Analysis of alterations of the metabolic network may lead to identify novel biomarkers and/or therapeutic target.     

Hemerodromia Seguyi,nouvel empidide d'Algérie destructeur de simulies

Résumé Dans une précédente note ont été étudiés les premiers stades d'un Empidide d'Algérie, de la sous-famille des Atalantinae, Roederella ouedorum, dont les larves, rhéophiles, détruisent les larves et surtout les nymphes de Simulium sp. Un autre Empidide d'Algérie, de la sous-famille des Hemerodromiinae, Hemerodromia seguyi, dont la larve, la nymphe et l'imago sont décrites ici, a un mode de vie tout à fait analogue; sa larve vit au sein des colonies de larves de Simulies; ces dernières sont capturées et sucées par la larve prédatrice. La nymphe d'Hemerodromia seguyi est nue et fixée sous des pierres immergées, dans des zônes de courant faible.Summary In a swift stream of the Aures mountains (Algeria), were collected, on April 1950, a large number of larvae of an Empidid fly of the subfamily Hemerodromiinae: Hemerodromia (Metachela) seguyi n. sp.; they live on immerged rocks, among larvae of Simulium sp., upon which they prey; when feeding, the Empidid larva buries its head in its prey and sucks up the flesh. Pupation takes place usually in crevices of immerged rocks at the water's edge, where the current is slow.The larva and pupa of H. seguyi have been compared respectively to those of Roederella ouedorum, an Empidid fly belonging to the subfamily Atalantinae. The main differences between the larvae are not furnished by the head structure, but by the number of abdominal prolegs, the disposition of hooks on them and the form of the prominence at the end of the body. Pupae of Hemerodromia are easy to distinguish from pupae of other Empidids, for they have eight pairs of long tracheal filaments; other taxonomic characters are the form of the plates of the head on ventral aspect and the disposition of spines on the abdomen.     

L’analyse métabolomique par spectrométrie de masse: un nouvel outil pour la biochimie clinique ?

Metabolomics (large scale analysis of small organic compounds) becomes a promising tool in biological exploration. This tool is able to identify modifications in biofluids occurring as a consequence of a pathogenic process. It’ll be shown how to carry out metabolomic analysis as well as the technological progress in this field. Concrete applications will be commented and the principal limitations will also be discussed. These limitations have to be overcome in order obtain data usable by biologists and medical doctors.     

Les Néandertaliens d’El Sidrón (Asturies,Espagne). Actualisation d’un nouvel échantillon

This paper synthesizes and updates the information coming from the El Sidrón (Asturias, Northern Spain) neandertal site. Since 2000, a new sample of Homo neanderthalensis dated to at least 49,000 years old is being systematically recovered at the El Sidrón cave site. The bone assemblage is located in a secondary position, and certainly derives from a close location. The sample is almost exclusively composed of human remains. There is a moderate number of Middle Paleolithic stone tools (n ≈ 415) and very few macro-faunal remains. All skeletal parts are preserved, including some rare bones such as the hyoid bone. Teeth are abundant (n = 213), cranial and postcranial remains are also well represented, but fragmentary, with a special presence of foot and hand bones. A minimum number of thirteen individuals has been identified, comprising different developmental stages from infancy to adulthood: one infant, two juveniles, three adolescents, and seven adults. Paleobiology of the El Sidrón humans fits the pattern found in other neandertal samples: a high incidence of dental hypoplasia and interproximal grooves, yet no serious traumatic lesions are present. Moreover, unambiguous evidence of human-induced modifications (cannibalism) was found on the human remains: cut marks, percussion pitting, conchoidal scars and adhering flakes. Individuals seem to have been treated differentially. Morphologically, the El Sidrón humans show a large number of neandertal lineage-derived features even though certain traits place the sample at the limits of neandertal variation. Integrating the El Sidrón human mandibles and occipital bones into the larger neandertal sample reveals a possible geographic patterning, with southern Neandertals showing broader faces with increased lower facial heights. Ancient DNA analyses have been carried out, developing an anti-contamination protocol of excavation for minimizing the risk of modern human DNA contamination. As a result both mitochondrial and nuclear DNA have been extracted from dental and osteological remains. Curiously, mtDNA comparative analyses suggest a population affinity of Iberian Peninsula Neandertals with Central European Neandertals. Nuclear DNA analyses have permitted the identification of some functional genes such as the melanocortin 1 receptor (MC1R), which regulates hair and skin pigmentation; the FOXP2, a gene involved in the development of language; and the gene involved in the ABO blood group system. Nowadays the large El Sidrón sample is the most significant neandertal sample from the Iberian Peninsula, and augments the European evolutionary lineage fossil record, supporting ecogeographical variability across neandertal populations.