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1.
Eur. j. anat ; 24(1): 49-56, ene. 2020. tab, ilus
Artículo en Inglés | IBECS | ID: ibc-186064

RESUMEN

The anatomical variations of the intracranial venous dural sinuses must be put in consideration in diagnosing magnetic resonance venography (MRV) to avoid the diagnostic pitfalls resulting from over-diagnosis of cerebral venous dural sinus occlusion or thrombosis. The available data regarding the age and sex difference of the magnetic resonance venography (MRV) anatomical variations is still limited. A retrospective study is done for 500 patients ranging from 20 to 70 years. Only 363 patients (142 males and 221 females) were included in our final analysis: all have normal MRI brain & posterior fossa. Magnetic resonance venography (MRV) is done to detect the presence or absence of the transverse venous dural sinuses and to detect any age-or sex-related differences. Also 64 dry Egyptian skulls (41 males and 23 females) were employed to detect symmetry of transverse sulcus and to determine age and sex difference. Hypoplastic left transverse sinus was by far the commonest asymmetrical transverse sinus variants representing 22.0% of total: it was noted in 38 male and 38 female. Even if the asymmetrical transverse sinus is more common in females, there is no significant difference between both genders. In the dry skull, symmetrical transverse sulcus was observed in 67.2% of total, while asymmetrical transverse sulcus was recorded in 32.8% of total, which were more observed in female skull 17.2% of total with no significant difference


No disponible


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Variación Anatómica , Flebografía/métodos , Senos Craneales/anomalías , Senos Craneales/diagnóstico por imagen , Trombosis de los Senos Intracraneales/diagnóstico por imagen , Cráneo/anomalías , Cráneo/anatomía & histología , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Senos Craneales/anatomía & histología , Estudios Retrospectivos , Diferenciación Sexual , Egipto , Determinación de la Edad por el Esqueleto , Cráneo/diagnóstico por imagen
2.
Adv Exp Med Biol ; 1232: 33-38, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31893391

RESUMEN

Monitoring of cerebral tissue oxygen saturation (StO2) by near-infrared spectroscopy (NIRS oximetry) has great potential to reduce the incidence of hypoxic and hyperoxic events and thus prevent long-term disabilities in preterm neonates. Since the light has to penetrate superficial layers (bone, skin and cerebrospinal fluid) before it reaches the brain, the question arises whether these layers influence cerebral StO2 measurement. We assessed this influence on the accuracy of cerebral StO2 values. For that purpose, we simulated light propagation with 'N-layered medium' software. It was found that with a superficial layer thickness of ≤6 mm, typical for term and preterm neonates, StO2 accurately reflects cerebral tissue oxygenation.


Asunto(s)
Oximetría , Oxígeno , Cráneo , Encéfalo/metabolismo , Humanos , Hipoxia/diagnóstico , Recién Nacido , Oximetría/normas , Cráneo/anatomía & histología , Espectroscopía Infrarroja Corta
3.
World Neurosurg ; 133: e293-e302, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31520764

RESUMEN

OBJECTIVE: Interest in endoscopic transnasal access has increased with continued technological advances in endoscopic technology. The goals of this study were to review the normal anatomy in transnasal endoscopic neurosurgery and outline the anatomical basis for an expanded surgical approach. Defining anatomical aspects of surgical endoscopy helps guide the surgeon by defining normal anatomy of the access vector. METHODS: This anatomic study was conducted on 15 adult male cadaver specimens using various microsurgical tools and endoscopic instruments and 1 intraoperative case. The vasculature was injected with colored silicone to aid visualization. Different transnasal approach techniques were used, with angles of endoscope access at 0°, 30°, 45°, and 70° accordingly for extensive anatomical mapping. RESULTS: The proximity of critical structures is different in each approach degree. A full understanding of the possible structures to be met during transnasal access is described. As a result of the study, anatomical aspects and important structures were outlined, and a surgical protocol was defined for minimal risk access in respect to normal anatomy of the area. CONCLUSIONS: Thorough knowledge of topographic anatomy of the craniovertebral junction is required for performing minimal-risk surgical intervention in this region. It is important to know all anatomical aspects of the transnasal approach in order to reduce the risk of damage to vital structures. Transnasal endoscopic surgery of the craniovertebral junction is a relatively new direction in neurosurgery; therefore, anatomical studies such as the one described in this article are extremely important for the development of this access method.


Asunto(s)
Cirugía Endoscópica por Orificios Naturales/métodos , Neuroendoscopía/métodos , Adulto , Cadáver , Vértebras Cervicales/anatomía & histología , Humanos , Masculino , Cavidad Nasal , Cráneo/anatomía & histología
4.
Forensic Sci Int ; 306: 110092, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31816484

RESUMEN

Metric assessment of human crania can provide forensic practitioners and anthropological researchers with information on an individual's sex and biogeographical ancestry. However, metric methods rely on the ability of users to remain consistent with themselves and others, with any error in the data rendering conclusions invalid. Digital anthropology is a growing sub-field where human remains are digitised using a growing range of methods and technologies. These models have the potential to boost research collaboration and public engagement. However, not all of these digitisation methods have been examined critically to explore the veracity of their use within a research environment. There has also been limited research into the application of digital anthropology to craniometric analysis. This study examined the intra- and inter- observer variation of seven participants taking physical measurements from a human cranial cast with an associated set of reference values. The same measurements were also taken from three digital models of the cranial cast which were created using digital photogrammetry and laser scanning. This data was then compared to the reference values and the physical measurements taken by the lead author. This study found that there was excellent statistical agreement between the reference values and the measurements taken from the cranial cast, both physical and digital. However, the participants still exhibited variation within a range of -18mm and +30mm from the reference values. MANOVA tests showed between-subject effects on nine measurements across the participant data, and 12 measurements between the digital models. However, there is little consistency between this study and the anthropological literature as to which measurements are most prone to between-subject effects. Despite the excellent agreement shown between the reference values and the digital models this study raises a number of methodological questions regarding inter-observer error and the varying levels of data processing present in different digitisation methods.


Asunto(s)
Cefalometría/métodos , Simulación por Computador , Imagen Tridimensional , Cráneo/anatomía & histología , Cráneo/diagnóstico por imagen , Antropología Forense , Humanos , Rayos Láser , Masculino , Variaciones Dependientes del Observador , Fotogrametría , Valores de Referencia
5.
Gene ; 729: 144282, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31838250

RESUMEN

The crested duck was a duck breed which features a topknot of feathers on the back of their head. In order to explain the reason of crest, we anatomy the head of some crested ducks. The anatomical structures showed that there was a fat body in the head and a hole in the skull. To determine the reason for the formation of the crest, we used whole genome re-sequencing to detect SNPs and InDels in three crested duck and three normal crested duck (without crest). There were 785,202 unique SNPs and 105,596 unique InDels include in crested duck. There were 14,591 SNPs containing genes and 13,784 InDels continuing genes were mapped on BGI_duck_1.0 by BWA 0.7.16a software. We use KEGG and GO to classification the SNP and InDel containing genes function. The PPI network of SNP containing genes and InDels containing genes was constructed by STRING. The result of PPI and KEGG analysis shown that the formation of crest might include feather development, fatty acid deposition, and skull hypoplasia. To determine the regulated of SNP containing genes and InDels containing genes, which related the different trait, of miRNA we used mirmap to predicted target miRNA of those genes. The miRNA-genes network constructed by Cytoscape. In conclusion, the formation of the crest was a complex process. The fatty acid metabolism block, feather growth and skull hypoplasia might lead crest formation. The tissue expression of four candidate genes showed that they were closely related to the formation of the trait, and could be used as important candidate genes to further elaborate the molecular mechanism of their function.


Asunto(s)
Patos/genética , Perfilación de la Expresión Génica/métodos , Animales , Animales Domésticos/genética , Cruzamiento , Patos/anatomía & histología , Ácidos Grasos/metabolismo , Plumas/metabolismo , Genotipo , Mutación INDEL/genética , Fenotipo , Polimorfismo Genético/genética , Cráneo/anomalías , Cráneo/anatomía & histología , Transcriptoma/genética , Secuenciación Completa del Genoma/métodos
6.
Forensic Sci Int ; 304: 109965, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31610333

RESUMEN

Facial soft tissue thicknesses (FSTT) form a key component of craniofacial identification methods, but as for any data, embedded measurement errors are highly pertinent. These in part dictate the effective resolution of the measurements. As herein reviewed, measurement methods are highly varied in FSTT studies and associated measurement errors have generally not been paid much attention. Less than half (44%) of 95 FSTT studies comment on measurement error and not all of these provide specific quantification. Where informative error measurement protocols are employed (5% of studies), the mean error magnitudes range from 3% to 45% rTEM and are typically in the order of 10-20%. These values demonstrate that FSTT measurement errors are similar in size to (and likely larger than) the magnitudes of many biological effects being chased. As a result, the attribution of small millimeter or submillimeter differences in FSTT to biological variables must be undertaken with caution, especially where they have not been repeated across different studies/samples. To improve the integrity of FSTT studies and the reporting of FSTT measurement errors, we propose the following standard: (1) calculate the technical error of measurement (TEM or rTEM) in any FSTT research work; (2) assess the error embedded in the full data collection procedure; and (3) conduct validation testing of FSTT means proposed for point estimation prior to publication to ensure newly calculated FSTT means provide improvements. In order to facilitate the latter, a freely available R tool TDValidator that uses the C-Table data for validation testing is provided.


Asunto(s)
Cara/anatomía & histología , Cara/diagnóstico por imagen , Biopsia , Cefalometría , Recolección de Datos , Diagnóstico por Imagen/métodos , Medicina Legal , Humanos , Imagen Tridimensional , Punciones , Caracteres Sexuales , Piel/patología , Cráneo/anatomía & histología , Cráneo/diagnóstico por imagen , Posición Supina
7.
Neurochirurgie ; 65(5): 210-215, 2019 Nov.
Artículo en Francés | MEDLINE | ID: mdl-31586575

RESUMEN

The vault of the skull is a region of the neurocranium formed by a process of membranous ossification. It consists of several bones: frontal bone, parietal bone, squamous part of the temporal bone, lamina ascendens of the sphenoid, and interparietal bone. The embryological origin of the bones of the skull vault is still the subject of controversy. This can be explained by the different animal models used for these purposes, but also by the various techniques applied to this problem. At all events, it seems that the cells of the neural crest generate some of the bones of the vault and that the others are derived from the mesoderm. This uncertainty should lead readers to be extremely cautious before using the presumptive maps published in the literature. Several tissues interact with osteo-progenitor cells: neural tube, surface ectoderm and dura mater. Analysis of genes in which mutations lead to abnormalities of the skull vault has partly revealed the molecular interactions. These are very complex and are the field of very numerous experimental investigations. In the relatively near future, we can hope to discover some of the molecular networks leading to the formation of these bony structures.


Asunto(s)
Cráneo/crecimiento & desarrollo , Animales , Femenino , Humanos , Cresta Neural/crecimiento & desarrollo , Embarazo , Cráneo/anatomía & histología , Cráneo/embriología
8.
World Neurosurg ; 131: 313-320, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31658575

RESUMEN

Learning the endless intricacies of operative neurosurgical anatomy requires that surgeons complement their intraoperative experiences with a variety of educational resources. In the past 2 decades, rapid improvements in digital graphics and computing power have enabled a new generation of 3-dimensional (3D) virtual resources that overcome limitations of more traditional 2-dimensional materials. Today, dozens of immersive 3D visualization platforms exist for applications such as learning neuroanatomy, simulating operative techniques, and planning surgical interventions with patient-specific models. The purpose of this article is to identify current applications of 3D digital modeling and virtual reality in neurosurgery. In addition, we showcase a new series of freely available 3D virtual-reality models created to assist in learning complex cranial anatomy. We anticipate these models to have a wide range of educational, clinical, and research applications. Three-dimensional visualization is poised to modernize the ways we learn and teach neurosurgical anatomy outside of the operating room. Future generations of neurosurgeons are expected to benefit from these technologies from the earliest stages of training.


Asunto(s)
Internado y Residencia/métodos , Modelos Anatómicos , Procedimientos Neuroquirúrgicos/educación , Cráneo/anatomía & histología , Realidad Virtual , Diseño de Equipo , Humanos , Imagen Tridimensional , Internet , Tornillos Pediculares , Impresión Tridimensional
9.
Nature ; 574(7779): 527-531, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31645719

RESUMEN

The known diversity of tetrapods of the Devonian period has increased markedly in recent decades, but their fossil record consists mostly of tantalizing fragments1-15. The framework for interpreting the morphology and palaeobiology of Devonian tetrapods is dominated by the near complete fossils of Ichthyostega and Acanthostega; the less complete, but partly reconstructable, Ventastega and Tulerpeton have supporting roles2,4,16-34. All four of these genera date to the late Famennian age (about 365-359 million years ago)-they are 10 million years younger than the earliest known tetrapod fragments5,10, and nearly 30 million years younger than the oldest known tetrapod footprints35. Here we describe Parmastega aelidae gen. et sp. nov., a tetrapod from Russia dated to the earliest Famennian age (about 372 million years ago), represented by three-dimensional material that enables the reconstruction of the skull and shoulder girdle. The raised orbits, lateral line canals and weakly ossified postcranial skeleton of P. aelidae suggest a largely aquatic, surface-cruising animal. In Bayesian and parsimony-based phylogenetic analyses, the majority of trees place Parmastega as a sister group to all other tetrapods.


Asunto(s)
Fósiles , Filogenia , Vertebrados/anatomía & histología , Animales , Teorema de Bayes , Paladar (Hueso)/anatomía & histología , Federación de Rusia , Cráneo/anatomía & histología , Vertebrados/clasificación
10.
Nature ; 573(7773): 200-202, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31501580
11.
Nat Commun ; 10(1): 3406, 2019 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-31506422

RESUMEN

The origin of Homo sapiens remains a matter of debate. The extent and geographic patterning of morphological diversity among Late Middle Pleistocene (LMP) African hominins is largely unknown, thus precluding the definition of boundaries of variability in early H. sapiens and the interpretation of individual fossils. Here we use a phylogenetic modelling method to predict possible morphologies of a last common ancestor of all modern humans, which we compare to LMP African fossils (KNM-ES 11693, Florisbad, Irhoud 1, Omo II, and LH18). Our results support a complex process for the evolution of H. sapiens, with the recognition of different, geographically localised, populations and lineages in Africa - not all of which contributed to our species' origin. Based on the available fossils, H. sapiens appears to have originated from the coalescence of South and, possibly, East-African source populations, while North-African fossils may represent a population which introgressed into Neandertals during the LMP.


Asunto(s)
Biodiversidad , Hominidae/fisiología , Modelos Biológicos , Filogenia , África , Animales , Fósiles/anatomía & histología , Hominidae/anatomía & histología , Humanos , Filogeografía , Cráneo/anatomía & histología
12.
BMC Evol Biol ; 19(1): 167, 2019 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-31390981

RESUMEN

BACKGROUND: Little is known about the long-term patterns of body size evolution in Crocodylomorpha, the > 200-million-year-old group that includes living crocodylians and their extinct relatives. Extant crocodylians are mostly large-bodied (3-7 m) predators. However, extinct crocodylomorphs exhibit a wider range of phenotypes, and many of the earliest taxa were much smaller (< 1.2 m). This suggests a pattern of size increase through time that could be caused by multi-lineage evolutionary trends of size increase or by selective extinction of small-bodied species. Here, we characterise patterns of crocodylomorph body size evolution using a model fitting-approach (with cranial measurements serving as proxies). We also estimate body size disparity through time and quantitatively test hypotheses of biotic and abiotic factors as potential drivers of crocodylomorph body size evolution. RESULTS: Crocodylomorphs reached an early peak in body size disparity during the Late Jurassic, and underwent an essentially continual decline since then. A multi-peak Ornstein-Uhlenbeck model outperforms all other evolutionary models fitted to our data (including both uniform and non-uniform), indicating that the macroevolutionary dynamics of crocodylomorph body size are better described within the concept of an adaptive landscape, with most body size variation emerging after shifts to new macroevolutionary regimes (analogous to adaptive zones). We did not find support for a consistent evolutionary trend towards larger sizes among lineages (i.e., Cope's rule), or strong correlations of body size with climate. Instead, the intermediate to large body sizes of some crocodylomorphs are better explained by group-specific adaptations. In particular, the evolution of a more aquatic lifestyle (especially marine) correlates with increases in average body size, though not without exceptions. CONCLUSIONS: Shifts between macroevolutionary regimes provide a better explanation of crocodylomorph body size evolution on large phylogenetic and temporal scales, suggesting a central role for lineage-specific adaptations rather than climatic forcing. Shifts leading to larger body sizes occurred in most aquatic and semi-aquatic groups. This, combined with extinctions of groups occupying smaller body size regimes (particularly during the Late Cretaceous and Cenozoic), gave rise to the upward-shifted body size distribution of extant crocodylomorphs compared to their smaller-bodied terrestrial ancestors.


Asunto(s)
Tamaño Corporal , Fósiles , Reptiles/genética , Animales , Evolución Biológica , Modelos Genéticos , Filogenia , Reptiles/clasificación , Reptiles/fisiología , Cráneo/anatomía & histología
13.
Comput Methods Programs Biomed ; 179: 104982, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31443869

RESUMEN

BACKGROUND AND OBJECTIVE: Transcranial focused ultrasound (tFUS) is a promising neuromodulation technique because of its non-invasiveness and high spatial resolution (within millimeter scale). However, the presence of the skull can lead to disrupting and shifting the acoustic focus in the brain. In this study, we propose a computationally efficient way to determine the optimal position of a single-element focused ultrasound transducer which can effectively deliver acoustic energy to the brain target. We hypothesized that the placement of a single element transducer with the lowest average reflection coefficient would be the optimal position. METHODS: The reflection coefficient is defined by the ratio of the amplitude of the reflected wave to the incident wave. To calculate the reflection coefficient, we assumed ultrasound waves as straight lines (beam lines). At each beam line, the reflection coefficient was calculated from the incidence angle at the skull interface (outer/inner skull surfaces). The average reflection coefficient (ARC) was calculated at each possible placement of the transducer using a custom-built software. For comparison purposes, acoustic simulations (k-Wave MATLAB toolbox) which numerically solved the linear wave equation were performed with the same transducer positions used in the ARC calculation. In addition, the experimental validation of our proposed method was also performed by measuring acoustic wave propagation through the calvaria skull phantom in water. The accuracy of our method was defined as the distance between the two optimal transducer placements which were determined from the acoustic simulations and from the ARC method. RESULT: Simulated acoustic pressure distribution corresponding to each ARC showed an inverse relationship with peak acoustic pressures produced in the brain. In comparison to the acoustic simulations, the accuracy of our method was 5.07 ± 4.27 mm when targeting the cortical region in the brain. The computing time of ARC calculations were 0.08% of the time required for acoustic pressure simulations. CONCLUSION: We calculated the ARC to find the optimal position of the tFUS transducer used in the present study. The optimal placement of the transducer was found when the ARC was the lowest. Our numerical and experimental results showed that the proposed ARC method can effectively be used to find the optimal position of a single-element tFUS transducer for targeting the cortex region of the brain in a computationally inexpensive way.


Asunto(s)
Cráneo , Transductores , Terapia por Ultrasonido/instrumentación , Acústica/instrumentación , Encéfalo/anatomía & histología , Simulación por Computador , Humanos , Imagen Tridimensional , Fantasmas de Imagen , Cráneo/anatomía & histología , Programas Informáticos , Terapia por Ultrasonido/métodos , Terapia por Ultrasonido/estadística & datos numéricos
14.
Nature ; 573(7773): 214-219, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31462770

RESUMEN

The cranial morphology of the earliest known hominins in the genus Australopithecus remains unclear. The oldest species in this genus (Australopithecus anamensis, specimens of which have been dated to 4.2-3.9 million years ago) is known primarily from jaws and teeth, whereas younger species (dated to 3.5-2.0 million years ago) are typically represented by multiple skulls. Here we describe a nearly complete hominin cranium from Woranso-Mille (Ethiopia) that we date to 3.8 million years ago. We assign this cranium to A. anamensis on the basis of the taxonomically and phylogenetically informative morphology of the canine, maxilla and temporal bone. This specimen thus provides the first glimpse of the entire craniofacial morphology of the earliest known members of the genus Australopithecus. We further demonstrate that A. anamensis and Australopithecus afarensis differ more than previously recognized and that these two species overlapped for at least 100,000 years-contradicting the widely accepted hypothesis of anagenesis.


Asunto(s)
Fósiles , Hominidae/anatomía & histología , Hominidae/clasificación , Cráneo/anatomía & histología , Animales , Diente Canino/anatomía & histología , Etiopía , Cara/anatomía & histología , Maxilar/anatomía & histología , Especificidad de la Especie , Hueso Temporal/anatomía & histología , Factores de Tiempo
15.
Forensic Sci Int ; 302: 109916, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31426020

RESUMEN

Several studies have shown variability in osteometric measurements of the skull between populations. Therefore, each population should have specific standards to optimize the accuracy of identification. The aim of this study was to evaluate the sexual dimorphism in metric relations between anatomical points of the skull using CT scans in a Jordanian population by means of discriminant function analysis, to determine which continuous variables discriminate between sexes, and to examine the craniofacial changes according to age. 500 CT scans (240 males and 260 females) were used and a total of 11 craniofacial parameters were studied. The data were analyzed using distriminant function analysis. Sexual dimorphism was found mainly in the young adult group. Significant age related changes were noticed in minimum frontal breadth, orbital height and orbital index. In all subjects, the analysis of multivariate (dimorphic variables) and stepwise functions gave an accuracy of 58.8% and 57.0% respectively. Using stepwise analysis, the most dimorphic variables to estimate sex were maximum frontal breadth, bimaxillary breadth and orbital index. The multivariate analysis of all variables gave an accuracy of 58.8%. The percentages of correct sexing in Jordanian population were high using the single variable analysis in females only. In females, classification accuracies of 70.4% using bimaxillary breadth, 70.0% using the orbital index, and 68.1% using maximum frontal breadth were obtained. Additionally, discriminant analysis was conducted separately for each age group. Higher percentages of correct sexing were obtained only in young adults. The results of the discriminant function analysis did not appear to be significant. The results of discriminant function were insignificant in middle aged and elderly groups. Being female and young increases the percentages of correct sexing. Generally, low levels of accuracy of sexual dimorphism were obtained in our study, suggesting that population estimates of dimorphism are highly variable and the equations derived from the discriminant function analysis are not reliable in sex estimation in Jordanians.


Asunto(s)
Determinación del Sexo por el Esqueleto/métodos , Cráneo/anatomía & histología , Cráneo/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Puntos Anatómicos de Referencia , Análisis Discriminante , Femenino , Antropología Forense , Humanos , Procesamiento de Imagen Asistida por Computador , Jordania , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Adulto Joven
16.
Primates ; 60(5): 401-419, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31468228

RESUMEN

Macaques are one of the most successful nonhuman primates, and morphological distinctions from their close relatives, African papionins, are easily detected by the naked eye. Nevertheless, evolutionary allometry often accounts for a large amount of the total variation and potentially hides and precludes the detection of morphological distinctions that exist between macaques and African papionins, thus distorting their phyletic comparison. Geometric morpgometric analyses were performed using landmark coordinates in cranial samples from macaques (N = 135) and African papionins (N = 152) to examine the variation in their facial shape. A common allometric trend was confirmed to represent a moderately long face in macaques as being small-to-moderate-bodied papionins. Macaques possessed many features that were distinct from those of African papionins, while they simultaneously showed a large intrageneric variation in every feature, which precluded the separation of some groups of macaques from African papionins. This study confirmed that a moderately smooth sagittal profile is present in non-Sulawesi macaques. It also confirmed that a well-developed anteorbital drop is distinct in Mandrillus and Theropithecus, but it showed that Papio resembles macaques regarding this feature. This finding showed that apparently equivalent features which can be detected by the naked eye were probably formed by different combinations of the principal patterns. It should be noted that the differences detected here between macaques and African papionins are revealed after appropriate adjustments are made to eliminate the allometric effects over the shape features. While landmark data sets still need to be customized for specific studies, the information provided by this article is expected to help such customization and to improve future phyletic evaluation of the fossil papionins.


Asunto(s)
Cercopithecinae/anatomía & histología , Cara/anatomía & histología , Cráneo/anatomía & histología , África , Animales , Femenino , Macaca/anatomía & histología , Masculino , Papio/anatomía & histología
17.
PLoS One ; 14(7): e0219716, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31295323

RESUMEN

The Dendropsophus decipiens clade comprises four species: D. berthalutzae, D. decipiens, D. haddadi, and D. oliveirai. Tadpoles of these species were described, but data on their internal morphology are lacking. We provide the first description of the buccopharyngeal anatomy, chondrocranial morphology, and cranial, hyoid and hyobranchial musculature of the tadpole of D. decipiens. Larvae of D. decipiens are characterized by the absence of lingual papillae, presence of fan-like papilla on the buccal floor, presence of a single-element suprarostral cartilage, presence of a small triangular process at the basis of the processus muscularis, m. levator mandibulae lateralis inserted on the nasal sac, and m. subarcualis rectus II-IV with a single, continuous slip. Tadpoles are likely macrophagous, although not as specialized as those of other species of the genus, suggesting some degree of diversification on the feeding habits within Dendropsophus.


Asunto(s)
Anuros/anatomía & histología , Larva/anatomía & histología , Mandíbula/anatomía & histología , Boca/anatomía & histología , Animales , Músculos/anatomía & histología , Filogenia , Cráneo/anatomía & histología
18.
PLoS One ; 14(7): e0218899, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31291291

RESUMEN

Genetic incompatibilities constitute the final stages of reproductive isolation and speciation, but little is known about incompatibilities that occur within recent adaptive radiations among closely related diverging populations. Crossing divergent species to form hybrids can break up coadapted variation, resulting in genetic incompatibilities within developmental networks shaping divergent adaptive traits. We crossed two closely related sympatric Cyprinodon pupfish species-a dietary generalist and a specialized molluscivore-and measured expression levels in their F1 hybrids to identify regulatory variation underlying the novel craniofacial morphology found in this recent microendemic adaptive radiation. We extracted mRNA from eight day old whole-larvae tissue and from craniofacial tissues dissected from 17-20 day old larvae to compare gene expression between a total of seven F1 hybrids and 24 individuals from parental species populations. We found 3.9% of genes differentially expressed between generalists and molluscivores in whole-larvae tissues and 0.6% of genes differentially expressed in craniofacial tissue. We found that 2.1% of genes were misregulated in whole-larvae hybrids whereas 19.1% of genes were misregulated in hybrid craniofacial tissues, after correcting for sequencing biases. We also measured allele specific expression across 15,429 heterozygous sites to identify putative compensatory regulatory mechanisms underlying differential expression between generalists and molluscivores. Together, our results highlight the importance of considering misregulation as an early indicator of genetic incompatibilities in the context of rapidly diverging adaptive radiations and suggests that compensatory regulatory divergence drives hybrid gene misregulation in developing tissues that give rise to novel craniofacial traits.


Asunto(s)
Quimera , Especiación Genética , Genética de Población , Killifishes/genética , Larva/genética , Animales , Cruzamientos Genéticos , Conducta Alimentaria , Femenino , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Flujo Génico , Heterocigoto , Killifishes/anatomía & histología , Killifishes/clasificación , Killifishes/crecimiento & desarrollo , Larva/anatomía & histología , Larva/crecimiento & desarrollo , Masculino , Fenotipo , Aislamiento Reproductivo , Cráneo/anatomía & histología , Cráneo/crecimiento & desarrollo , Cráneo/metabolismo , Simpatría
19.
Nature ; 571(7766): 500-504, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31292546

RESUMEN

Two fossilized human crania (Apidima 1 and Apidima 2) from Apidima Cave, southern Greece, were discovered in the late 1970s but have remained enigmatic owing to their incomplete nature, taphonomic distortion and lack of archaeological context and chronology. Here we virtually reconstruct both crania, provide detailed comparative descriptions and analyses, and date them using U-series radiometric methods. Apidima 2 dates to more than 170 thousand years ago and has a Neanderthal-like morphological pattern. By contrast, Apidima 1 dates to more than 210 thousand years ago and presents a mixture of modern human and primitive features. These results suggest that two late Middle Pleistocene human groups were present at this site-an early Homo sapiens population, followed by a Neanderthal population. Our findings support multiple dispersals of early modern humans out of Africa, and highlight the complex demographic processes that characterized Pleistocene human evolution and modern human presence in southeast Europe.


Asunto(s)
Cuevas , Fósiles , Cráneo/anatomía & histología , Animales , Evolución Biológica , Grecia , Humanos , Hombre de Neandertal/anatomía & histología , Hombre de Neandertal/clasificación , Análisis de Componente Principal , Datación Radiométrica , Factores de Tiempo
20.
J Craniofac Surg ; 30(7): e623-e626, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31261338

RESUMEN

BACKGROUND: Infraorbital foramen (IOF) is an important anatomical landmark in cleft lip surgery. The location of IOF within the maxilla of infants is different from adults. However, little information about anatomy of IOF in infants exists in the literature. This study aims to determine the location of IOF in infant dry skulls based on key surgical landmarks. METHODS: All dry skulls under age 2 years old were selected from the Hamann-Todd Human Osteological Collection at the Cleveland Museum of Natural History (Cleveland, OH). Specimens without cranial bones or complete maxilla were excluded. Seven anatomical measurements were taken on each side of the face for each individual skull (14 measurements for each skull). Anatomical landmarks used for the measurements included infraorbital rim, aperture piriformis, alveolar ridge, zygomaticomaxillary buttress, anterior nasal spine (ANS), and inferolateral corner of the aperture piriformis. RESULTS: Twenty-seven halves of 14 dry skulls were included in the final analysis. The mean age of specimens was 0.57 years. Mean distances from infraorbital foramen to infraorbital rim, aperture piriformis, alveolar ridge, zygomaticomaxillary, and ANS buttress were 4.11 ±â€Š0.82, 9.4 ±â€Š1.62, 12.7 ±â€Š2.71, 11.7 ±â€Š1.54, and 18.4 ±â€Š2.11 mm, respectively. CONCLUSION: This study also shows that the infraorbital foramen in infants is located at the level of the ANS or within 2 mm higher and that the distance between the infraorbital rim and foramen is only 3 to 4 mm. These findings should be applied to the cleft population with discretion.


Asunto(s)
Labio Leporino , Maxilar/anatomía & histología , Cráneo/anatomía & histología , Proceso Alveolar/anatomía & histología , Cadáver , Preescolar , Labio Leporino/cirugía , Femenino , Humanos , Lactante , Masculino , Museos , Órbita/anatomía & histología
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