Variation and Characteristics of the Cranial Vault Thickness in the Krapina and Western European Neandertals

The Krapina collection constitutes the largest sample of Neandertal individuals. However, comparisons of these fossils with other Western European Neandertals have been limited because of the fragmentary condition of the Krapina specimens and because gracility and small dimensions of the cranial remains were attributed to phylogeny and to geological age or to a sex/age bias in the composition of the sample. This study focuses on cranial vault thickness to document new evidence on its variation in the Neandertals. The results demonstrate the similarities between Krapina and the Western European Neandertals in thickness of the cranial vault along the mid-sagittal plane. Finally, Neandertals have characteristics that distinguish them from anatomically modern Homo sapiens fossils

The vimentin-tubulin binding site peptide (Vim-TBS.58-81) crosses the plasma membrane and enters the nuclei of human glioma cells

Cell-penetrating peptides (CPPs) can translocate through the plasma membrane and localize in different cell compartments providing a promising delivery system for peptides, proteins, nucleic acids, and other products. Here we describe features of a novel cell-penetrating peptide derived from the intermediate filament protein vimentin, called Vim-TBS.58-81. We show that it enters cells from a glioblastoma line via endocytosis where it distributes throughout the cytoplasm and nucleus. Moreover, when coupled to the pro-apoptogenic peptide P10, it localizes to the nucleus inhibiting cell proliferation. Thus, the Vim-TBS.58-81 peptide represents an effective vector for delivery of peptides and potentially a broad range of cargos to the nucleus

Are thickened cranial bones and equal participation of the three structural bone layers autapomorphic traits of Homo erectus?

Numerous studies have proposed different lists of morphological features to define the species of Homo erectus; among these, some are considered to be autapomorphic. The intention of this study is to discuss two of these possible autapomorphic traits: thickened cranial bones and equal participation of the three structural bone layers (inner and outer tables, diploe) in this thickening. This study brings new information concerning cranial vault thickness and structural composition in the mid-sagittal plane of some Asian Homo erectus. The Ngandong and Sambungmacan fossils, as well as the Zhoukoudian and Sangiran individuals, have cranial vault thickness values within the range of variation observed in our Homo sapiens comparative sample. Moreover, even if the frontal and sagittal keels in Homo erectus constitute a relief on the external cranial vault surface, they do not necessary correspond to a real thickening of the underlying bone. The diploic layer principally contributes to their internal composition. Similarly, the diploe constitutes the greatest part of the total vault thickness along the mid-sagittal plane, particularly in the frontal and occipital tori, in the analysed fossils of this extinct species. Finally, our results show that Homo erectus individuals have cortical tables as well as diploe variation and distribution patterns similar to anatomically modern Homo sapiens. Therefore, the two tested autapomorphic traits for Homo erectus can no longer be considered as valid. L’épaisseur importante de la voûte crânienne et l’hyperossification de la table compacte externe, deux caractères considérés comme autapomorphiques pour l’espèce Homo erectus, sont étudiés. La variation de l’épaisseur et sa constitution interne ont été analysées le long du plan sagittal médian chez des représentants de l’espèce Homo erectus. Les fossiles de Ngandong, Sambungmacan, Sangiran et Zhoukoudian étudiés ont dans l’ensemble des valeurs d’épaisseur crânienne qui se situent dans la variabilité de notre échantillon d’Hommes anatomiquement modernes. De plus, les fossiles attribués à Homo erectus et Homo sapiens partagent le même schéma de distribution de l’épaisseur crânienne et des tables osseuses le long du plan sagittal médian. Si la carène sagittale chez Homo erectus constitue un relief osseux externe, elle ne correspond pas nécessairement à un réel épaississement de l’os sous-jacent, ni à celui de la table compacte externe comme admis jusque là. Le diploé en compose la majeure partie comme cela est observé sur les torus frontal et occipital transverse. Les caractères testés ne sont donc pas des autapomorphies de l’espèce Homo erectus

Nouvelles données sur les caractéristiques morphologiques immatures du crâne chez les Homo erectus asiatiques

L’identification des spécimens immatures au sein de l’enregistrement fossile est primordial, aussi bien dans la perspective de déterminer la variabilité adulte des différents taxons, que pour aborder leurs caractéristiques ontogénétiques et phylogénétiques. En ce qui concerne les fossiles asiatiques attribués à Homo erectus, seulement quelques restes crâniens d’individus immatures ont été mis au jour et ces spécimens se distribuent sur une très grande période chronologique. Dans ce contexte, l’objectif de cette étude est, d’une part, de tester la validité des caractères généralement employés pour estimer le stade de développement de ces fossiles ; d’autre part, d’apporter des nouvelles données à notre connaissance des caractéristiques morphologiques immatures du squelette céphalique pour l’espèce Homo erectus. L’utilisation des standards de croissance définis chez l’Homme moderne n’apparaît pas appropriée pour étudier la croissance chez Homo erectus et les critères fréquemment utilisés pour discuter du stade de développement chez cette espèce fossile s’avèrent peu significatifs. En effet, les composantes osseuses internes se dissocient précocement et l’épaisseur crânienne peut atteindre la variabilité adulte à un stade de développement immature chez les fossiles asiatiques. Par ailleurs, les variations de forme et de conformation de l’endocrâne entre les spécimens non adultes et adultes chez Homo erectus suivraient une trajectoire différente de celle qui s’observe au cours de la croissance et du développement chez les Hommes modernes.It is critical to be able to recognize the juvenile specimens within the fossil record in order to determine the adult variability of the different taxa and to approach their ontogenetic and phylogenetic characteristics. Nevertheless, with regard to the Asian fossils assigned to Homo erectus, few cranial remains of juvenile individuals have been unearthed. Furthermore, these individuals are spread over a large chronological duration. Our purpose is to test the validity of the features generally used to estimate the developmental age of these fossils and to convey new information about the juvenile features of the cephalic skeleton in the species Homo erectus. Our results illustrate that growth standards defined for modern humans are not suitable to study the growth and development in Homo erectus. Moreover, the criteria frequently used to determine the development stage in Homo erectus would be barely meaningful. We show that the internal components of the cranial vault would differentiate at an early developmental age, as shown by the Mojokerto child. Similarly, cranial vault thickness would come within the adult range of variation early during growth, as shown for the frontal squama by Ngandong 2. The thickness of the frontal superstructures and of the occipital torus would increase later, but before the adult stage. This modification concerns all the internal components of the bone and principally the diploic layer. Moreover, our results suggest that the growth and development of the Homo erectus brain were different from those of modern humans. The transition from the endocranial shape of Mojokerto to the adult morphology for Homo erectus corresponds to a relative development of the frontal lobes, associated with an antero-posterior extension of the cerebral structures. Finally, the globularity of the brain and of the skull would persist late during the ontogenetic history in Homo erectus. The disappearance of these features would be due to an antero-posterior relative elongation of the endocast and of the cranial vault, as well as anterior enlargement of the frontal superstructures and posterior enlargement of the occipital superstructures

Nouvelles données sur les caractéristiques morphologiques immatures du crâne chez les Homo erectus asiatiques

L’identification des spécimens immatures au sein de l’enregistrement fossile est primordial, aussi bien dans la perspective de déterminer la variabilité adulte des différents taxons, que pour aborder leurs caractéristiques ontogénétiques et phylogénétiques. En ce qui concerne les fossiles asiatiques attribués à Homo erectus, seulement quelques restes crâniens d’individus immatures ont été mis au jour et ces spécimens se distribuent sur une très grande période chronologique. Dans ce contexte, l’objectif de cette étude est, d’une part, de tester la validité des caractères généralement employés pour estimer le stade de développement de ces fossiles ; d’autre part, d’apporter des nouvelles données à notre connaissance des caractéristiques morphologiques immatures du squelette céphalique pour l’espèce Homo erectus. L’utilisation des standards de croissance définis chez l’Homme moderne n’apparaît pas appropriée pour étudier la croissance chez Homo erectus et les critères fréquemment utilisés pour discuter du stade de développement chez cette espèce fossile s’avèrent peu significatifs. En effet, les composantes osseuses internes se dissocient précocement et l’épaisseur crânienne peut atteindre la variabilité adulte à un stade de développement immature chez les fossiles asiatiques. Par ailleurs, les variations de forme et de conformation de l’endocrâne entre les spécimens non adultes et adultes chez Homo erectus suivraient une trajectoire différente de celle qui s’observe au cours de la croissance et du développement chez les Hommes modernes.It is critical to be able to recognize the juvenile specimens within the fossil record in order to determine the adult variability of the different taxa and to approach their ontogenetic and phylogenetic characteristics. Nevertheless, with regard to the Asian fossils assigned to Homo erectus, few cranial remains of juvenile individuals have been unearthed. Furthermore, these individuals are spread over a large chronological duration. Our purpose is to test the validity of the features generally used to estimate the developmental age of these fossils and to convey new information about the juvenile features of the cephalic skeleton in the species Homo erectus. Our results illustrate that growth standards defined for modern humans are not suitable to study the growth and development in Homo erectus. Moreover, the criteria frequently used to determine the development stage in Homo erectus would be barely meaningful. We show that the internal components of the cranial vault would differentiate at an early developmental age, as shown by the Mojokerto child. Similarly, cranial vault thickness would come within the adult range of variation early during growth, as shown for the frontal squama by Ngandong 2. The thickness of the frontal superstructures and of the occipital torus would increase later, but before the adult stage. This modification concerns all the internal components of the bone and principally the diploic layer. Moreover, our results suggest that the growth and development of the Homo erectus brain were different from those of modern humans. The transition from the endocranial shape of Mojokerto to the adult morphology for Homo erectus corresponds to a relative development of the frontal lobes, associated with an antero-posterior extension of the cerebral structures. Finally, the globularity of the brain and of the skull would persist late during the ontogenetic history in Homo erectus. The disappearance of these features would be due to an antero-posterior relative elongation of the endocast and of the cranial vault, as well as anterior enlargement of the frontal superstructures and posterior enlargement of the occipital superstructures

La morphologie externe et interne de la région supra-orbitaire est-elle corrélée à des contraintes biomécaniques ? Analyses structurales des populations d’Homo sapiens d’Afalou Bou Rhummel (Algérie) et de Taforalt (Maroc)

Une analyse comparative et complémentaire est menée sur la morphologie externe des régions péri-orbitaires et maxillaires et sur la variabilité de la pneumatisation frontale chez des Hommes anatomiquement modernes du Paléolithique supérieur d’Afalou Bou Rhummel (Algérie) et de Taforalt (Maroc) ayant subi un nombre variable d’avulsions dentaires. Les résultats obtenus montrent que les conséquences de ces mutilations sont limitées à l’os pré-maxillaire. La morphologie adulte de l’os maxillaire n’a pas de modification en fonction du nombre d’incisives ôtées durant l’enfance. De même, celle des régions supra-orbitaires est homogène alors que la pneumatisation frontale, très variable dans son extension, montre une relation dans sa forme avec celle des structures osseuses. Les implications mécaniques liées à l’incision devaient être très variables selon le nombre d’avulsions. Les contraintes correspondantes n’ont pas eu d’influence sur la morphologie de la partie postérieure de l’os maxillaire, ni sur les superstructures de l’os frontal. La pneumatisation est aussi indépendante de ces caractéristiques dentaires et probablement de leurs implications fonctionnelles. Cette approche permet d’argumenter que les contraintes masticatoires ont une influence très limitée sur le développement des superstructures supra-orbitaires et qu’elles n’en sont aucunement la cause principale, au moins chez l’Homme moderne.The purpose of this study was to analyse and compare the external morphology of the supraorbital and maxillary regions as well as the variability of frontal pneumatisation in a sample of anatomically modern humans of the upper Palaeolithic of Afalou Bou Rhummel (Algeria) and Taforalt (Morocco), who underwent extraction of upper incisors. The results of the study show that the consequences of such mutilations are limited to the premaxilla and have no effect on the maxilla or the cranial superstructures. The supraorbital regions are homogeneous. However, the frontal pneumatisation, which is variable in its extension, has a similar morphology to the bone structures. Biomechanical stress has very limited influence on the development of the supraorbital structures, at least in modern humans

The effect of functionalizing lipid nanocapsules with NFL-TBS.40-63 peptide on their uptake by glioblastoma cells.

We previously described a neurofilament derived cell-penetrating peptide, NFL-TBS.40-63, that specifically enters in glioblastoma cells where it disturbs the microtubule network both in vitro and in vivo. The aim of this study is to test whether this peptide can increase the targeted uptake by glioblastoma cells of lipid nanocapsules filled with Paclitaxel, and thus can increase their anti-proliferation in vitro and in vivo. Here, using the drop tensiometry we show that approximately 60 NFL-TBS.40-63 peptides can bind to one 50 nm lipid nanocapsule. When nanocapsules are filled with a far-red fluorochrome (DiD) and Paclitaxel, the presence of the NFL-TBS.40-63 peptide increases their uptake by glioblastoma cells in culture as evaluated by FACS analysis, and thus reduces their proliferation. Finally, when such nanocapsules were injected in mice bearing a glioma tumour, they are preferentially targeted to the tumour and reduce its progression. These results show that nanocapsules functionalized with the NFL-TBS.40-63 peptide represent a powerful drug-carrier system for glioma targeted treatment

Structures internes claviculaires chez Pan, Gorilla et Homo. Méthode d’analyse et résultats préliminaires

Ce travail présente les résultats préliminaires d’une étude sur les structures claviculaires internes, par l’intermédiaire du scanner à rayon X. La morphologie complexe de cet os rend impossible la détermination d’un plan de coupe similaire et reproductible d’un individu à l’autre et interdit ainsi toute analyse classique des données scanographiques bidimensionnelles. Nous proposons un protocole inédit permettant de quantifier de manière précise et répétitive les variations volumiques en trois dimensions des structures morphologiques internes des clavicules. Celles-ci sont dissociées en trois ensembles distincts (structures osseuses denses, structures osseuses peu denses et porosité) en fonction de leur densité radiologique. Les premiers résultats montrent que les structures osseuses denses sont représentées par un volume plus important que les structures osseuses peu denses. De plus, les clavicules de chimpanzé sont caractérisées par un volume relatif des structures osseuses denses plus important que chez les gorilles et les hommes. Ceci s’exprime, entre autres, chez un quart des chimpanzés, par une absence des structures osseuses peu denses au point d’inflexion de la courbure acromiale. Ces différences peuvent être interprétées comme des adaptations aux contraintes subies par les clavicules.This study presents the preliminary results of an examination of internal clavicular structures using CT scan data analysis. The complex morphology of this bone makes the determination of a reproducible CT slice plane impossible and so any classical analysis of the two-dimensional CT data is ruled out. We propose a new protocol which enables quantification in three dimensions of the variations in volume of the internal morphological structures of the clavicles.  These are divided into three distinct groups (porosity, low density structures and high density structures) according to their radiological density. The first results show that the high density structures are represented by a larger volume than the low density structures. Moreover, chimpanzee clavicles are characterized by a relative volume of high density bone structure superior to that of gorillas and humans. For a quarter of chimpanzees, this is characterized by an absence of low density structures at the inflexion point of the acromial curvature. These differences can be interpreted as adaptations to the strains to which the clavicles are subjected

Neandertal-like traits visible in the internal structure of non-supranuchal fossae of some recent Homo sapiens: The problem of their identification in hominins and phylogenetic implications

Although recently the internal structure of the non-supranuchal fossa of Homo sapiens has been described and compared to that observed in the Neandertal suprainiac fossa, until now it has not been examined in any modern human children. In this study, the internal structure of this fossa in the occipital bones of three children (two aged 3–4 years and one aged 5 years ± 16 months) and one adult individual representing recent Homo sapiens from Australia was analysed and compared to that of the Neandertal suprainiac fossa. In order to analyse the internal composition of the fossae of the examined specimens, initially, high-resolution micro-CT datasets were obtained for their occipital bones; next, 3D topographic maps of the variation in thickness of structural layers of the occipital bones were made and 2D virtual sections in the median region of these fossae were prepared. In the fossa of one immature individual, the thinning of the diploic layer characteristic of a Neandertal suprainiac fossa was firmly diagnosed. The other Neandertal-like trait, concerning the lack of substantial thinning of the external table of the bone in the region of the fossa, was established in two individuals (one child and one adult) due to the observation of an irregular pattern of the thickness of this table in the other specimens, suggesting the presence of an inflammatory process. Our study presents, for the first time, Neandertal-like traits (but not the whole set of features that justifies the autapomorphic status of the Neandertal supraniac fossa) in the internal structure of non-supranuchal fossae of some recent Homo sapiens. We discuss the phylogenetic implications of the results of our analysis and stress the reasons that use of the 3D topographic mapping method is important for the correct diagnosis of Neandertal traits of the internal structure of occipital fossae

Shared Pattern of Endocranial Shape Asymmetries among Great Apes, Anatomically Modern Humans, and Fossil Hominins

Anatomical asymmetries of the human brain are a topic of major interest because of their link with handedness and cognitive functions. Their emergence and occurrence have been extensively explored in human fossil records to document the evolution of brain capacities and behaviour. We quantified for the first time antero-posterior endocranial shape asymmetries in large samples of great apes, modern humans and fossil hominins through analysis of “virtual” 3D models of skull and endocranial cavity and we statistically test for departures from symmetry. Once based on continuous variables, we show that the analysis of these brain asymmetries gives original results that build upon previous analysis based on discrete traits. In particular, it emerges that the degree of petalial asymmetries differs between great apes and hominins without modification of their pattern. We indeed demonstrate the presence of shape asymmetries in great apes, with a pattern similar to modern humans but with a lower variation and a lower degree of fluctuating asymmetry. More importantly, variations in the position of the frontal and occipital poles on the right and left hemispheres would be expected to show some degree of antisymmetry when population distribution is considered, but the observed pattern of variation among the samples is related to fluctuating asymmetry for most of the components of the petalias. Moreover, the presence of a common pattern of significant directional asymmetry for two components of the petalias in hominids implicates that the observed traits were probably inherited from the last common ancestor of extant African great apes and Homo sapiens