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1.
J Hum Evol ; 160: 102648, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-31611012

RESUMO

This study presents the dental remains discovered at Manot Cave (MC), Western Galilee, Israel. The cave contains evidence for human occupation during the Early Upper Paleolithic period (46-33 ka) mainly of Early Ahmarian (∼46-42 ka) and Levantine Aurignacian (∼38-34 ka) cultural levels. Six teeth (three deciduous and three permanent) were found at the site, of which four could be thoroughly analyzed. The morphology of the teeth was qualitatively described and analyzed using traditional and geometric morphometric methods. A large comparative sample was used in order to assess the morphological affiliation of the Manot specimens with other Homo groups. The results provided equivocal signals: the upper first premolar (MC-9 P3) is probably modern human; the upper deciduous second molar (MC-10 dm2) and the upper second permanent molar (MC-8 M2) might be modern humans; the lower second deciduous molar (MC-7 dm2) might be Neanderthal. Owing to the small sample size and the almost total lack of distinctive characteristics, our outcome could not supply conclusive evidence to address the question of whether Manot Aurignacian population came from Europe or descended from the local Ahmarian population.


Assuntos
Fósseis , Homem de Neandertal , Animais , Cavernas , Humanos , Israel , Dente Decíduo
2.
J Hum Evol ; 160: 102668, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-31629539

RESUMO

The transition from the Middle Paleolithic to the Upper Paleolithic in the Levant represents a major event in human prehistory with regards to the dispersal of modern human populations. Unfortunately, the scarcity of human remains from this period has hampered our ability to study the anatomy of Upper Paleolithic populations. This study describes and examines pedal bones recovered from the Early Upper Paleolithic period at Manot Cave, Israel, from 2014 to 2017. The Manot Cave foot bones include a partial, left foot skeleton comprising a talus, a calcaneus, a cuboid, a first metatarsal, a second metatarsal, a fifth metatarsal, and a hallucal sesamoid. All these remains were found in the same archaeological unit of the cave and belong to a young adult. Shape and size comparisons with Neanderthals, Anatomically Modern Human and modern human foot bones indicate a modern human morphology. In some characteristics, however, the Manot Cave foot bones display a Neanderthal-like pattern. Notably, the Manot Cave foot is remarkable in its overall gracility. A healed traumatic injury in the second metatarsal (Lisfranc's fracture) is most likely due to a remote impact to the dorsum of the foot. This injury, its subsequent debility, and the individual's apparent recovery suggest that the members of the Manot Cave community had a supportive environment, one with mutual responsibilities among the members.


Assuntos
Homem de Neandertal , Animais , Arqueologia , Cavernas , Ossos do Pé , Fósseis , Humanos , Israel
3.
J Hum Evol ; 160: 102734, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-32247528

RESUMO

Studying endocasts has long allowed anthropologists to examine changes in the external topography and the overall size of the brain throughout the evolutionary history of hominins. The nearly complete calvaria of Manot 1 presents an opportunity to gain insights into the external brain morphology, vascular system, and dimensions of the brain of this late Middle Paleolithic hominin. Detailed size and shape analyses of the Manot 1 endocast indicate a modern Homo sapiens anatomy, despite the presence of some primitive features of the calvaria. Traits considered to be derived endocranial features for H. sapiens are present in Manot 1, including an elongated parietal sagittal chord with an elevated superior part of the hemisphere, a widened posterior part of the frontal lobes, a considerable development of the parietal reliefs such as the supramarginal lobules, and a slight posterior projection of the occipital lobes. These findings, together with data presented in previous studies, rule out the possibility of a direct Neanderthal ancestry for the Manot 1 hominin and instead confirm its affiliation with H. sapiens. The Manot 1 calvaria is more similar to that of later Upper Paleolithic H. sapiens than it is to the earlier Levantine populations of Skhul and Qafzeh. The late Middle Paleolithic date of Manot 1 provides an opportunity to analyze the recent developments in human cerebral morphology and organization.


Assuntos
Hominidae , Homem de Neandertal , Animais , Evolução Biológica , Fósseis , Humanos , Israel , Crânio/anatomia & histologia
4.
Nature ; 520(7546): 216-9, 2015 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-25629628

RESUMO

A key event in human evolution is the expansion of modern humans of African origin across Eurasia between 60 and 40 thousand years (kyr) before present (bp), replacing all other forms of hominins. Owing to the scarcity of human fossils from this period, these ancestors of all present-day non-African modern populations remain largely enigmatic. Here we describe a partial calvaria, recently discovered at Manot Cave (Western Galilee, Israel) and dated to 54.7 ± 5.5 kyr bp (arithmetic mean ± 2 standard deviations) by uranium-thorium dating, that sheds light on this crucial event. The overall shape and discrete morphological features of the Manot 1 calvaria demonstrate that this partial skull is unequivocally modern. It is similar in shape to recent African skulls as well as to European skulls from the Upper Palaeolithic period, but different from most other early anatomically modern humans in the Levant. This suggests that the Manot people could be closely related to the first modern humans who later successfully colonized Europe. Thus, the anatomical features used to support the 'assimilation model' in Europe might not have been inherited from European Neanderthals, but rather from earlier Levantine populations. Moreover, at present, Manot 1 is the only modern human specimen to provide evidence that during the Middle to Upper Palaeolithic interface, both modern humans and Neanderthals contemporaneously inhabited the southern Levant, close in time to the likely interbreeding event with Neanderthals.


Assuntos
Cavernas , Fósseis , Filogenia , Crânio/anatomia & histologia , África/etnologia , Animais , Europa (Continente)/etnologia , Humanos , Israel , Homem de Neandertal/anatomia & histologia , Homem de Neandertal/fisiologia
5.
Nature ; 483(7391): 565-9, 2012 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-22460901

RESUMO

A newly discovered partial hominin foot skeleton from eastern Africa indicates the presence of more than one hominin locomotor adaptation at the beginning of the Late Pliocene epoch. Here we show that new pedal elements, dated to about 3.4 million years ago, belong to a species that does not match the contemporaneous Australopithecus afarensis in its morphology and inferred locomotor adaptations, but instead are more similar to the earlier Ardipithecus ramidus in possessing an opposable great toe. This not only indicates the presence of more than one hominin species at the beginning of the Late Pliocene of eastern Africa, but also indicates the persistence of a species with Ar. ramidus-like locomotor adaptation into the Late Pliocene.


Assuntos
Adaptação Fisiológica/fisiologia , Pé/anatomia & histologia , Pé/fisiologia , Marcha/fisiologia , Hominidae/anatomia & histologia , Hominidae/fisiologia , Caminhada/fisiologia , Animais , Evolução Biológica , Etiópia , Ossos do Pé/anatomia & histologia , Ossos do Pé/fisiologia , Fósseis , Humanos , Análise de Componente Principal
6.
Proc Natl Acad Sci U S A ; 107(27): 12121-6, 2010 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-20566837

RESUMO

Only one partial skeleton that includes both forelimb and hindlimb elements has been reported for Australopithecus afarensis. The diminutive size of this specimen (A.L. 288-1 ["Lucy"]) has hampered our understanding of the paleobiology of this species absent the potential impact of allometry. Here we describe a large-bodied (i.e., well within the range of living Homo) specimen that, at 3.58 Ma, also substantially antedates A.L. 288-1. It provides fundamental evidence of limb proportions, thoracic form, and locomotor heritage in Australopithecus afarensis. Together, these characteristics further establish that bipedality in Australopithecus was highly evolved and that thoracic form differed substantially from that of either extant African ape.


Assuntos
Fósseis , Hominidae/anatomia & histologia , Crânio/anatomia & histologia , Acetábulo/anatomia & histologia , Animais , Evolução Biológica , Etiópia , Cabeça do Fêmur/anatomia & histologia , Geologia , Locomoção , Paleontologia/métodos , Tíbia/anatomia & histologia , Fatores de Tempo
7.
Angle Orthod ; 91(4): 538-543, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33544141

RESUMO

OBJECTIVES: To examine the correlation between spheno-occipital synchondrosis fusion stages and the hand-wrist skeletal maturity index. MATERIALS AND METHODS: Digital records of 164 individuals (77 males, 87 females) aged 10 to 18 years old were examined. Three-dimensional CBCT scans and hand-wrist two-dimensional radiographs were scored for the spheno-occipital synchondrosis fusion stages and hand-wrist skeletal maturity index, respectively. Statistical analyses were performed for associations using R software with a significance threshold of P< .01. RESULTS: A significant positive relationship was demonstrated between spheno-occipital synchondrosis fusion stages and hand-wrist skeletal maturity in both sexes. The Kendall's rank correlation τ between hand-wrist skeletal maturity index and spheno-occipital synchondrosis fusion percentage were high and positive in males and females (r = .74 and r = .71, respectively). CONCLUSIONS: The significant, positive relationship between the hand-wrist skeletal maturity index and spheno-occipital synchondrosis fusion stages support the idea of using spheno-occipital synchondrosis fusion as a biological indicator for craniofacial and mandibular growth spurt prediction.


Assuntos
Osso Occipital , Osso Esfenoide , Adolescente , Determinação da Idade pelo Esqueleto , Criança , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Osso Occipital/diagnóstico por imagem , Osso Esfenoide/diagnóstico por imagem , Punho
8.
Am J Phys Anthropol ; 141(2): 273-80, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19672847

RESUMO

The British medieval population from Wharram Percy, England, has a greater prevalence of isthmic spondylolysis (11.9% of skeletons, 8.5% at the L5 level) than in modern populations (3%-6%). This may in part be due to differences in activity patterns between groups. However, Ward and Latimer (Spine 30 [2005] 1808-1814) proposed that the likelihood of developing and maintaining spondylolytic defects is also influenced by a lack of sufficient increase in mediolateral separation between articular processes in the lowest lumbar segments, given the human lumbar lordosis. Here, we demonstrate that spondylolytic individuals from Wharram Percy tend to have a less pronounced difference between mediolateral facet joint spacing of adjacent segments in the lowest lumbar region than do unaffected individuals, as seen in modern clinical and skeletal populations. These comparisons suggest that regardless of lifestyle, insufficient mediolateral increase in facet spacing predisposes people to spondylolytic defects, and so interfacet spacing patterns may have predictive utility in a clinical context. We also compare the Wharram Percy sample to a modern sample from the Hamann Todd collection with a typically modern prevalence rate. Data do not support the hypothesis that the Wharram Percy individuals had a less pronounced interfacet increase than the Hamann Todd, although they do have narrower lumbar facet spacing at the lowest three levels. Further investigation of anatomical variation underlying population-specific prevalence rates needs to be conducted.


Assuntos
Fósseis , Vértebras Lombares/patologia , Espondilólise/patologia , Articulação Zigapofisária/patologia , Antropometria , Inglaterra , História Medieval , Humanos , Paleopatologia
9.
Am J Phys Anthropol ; 141(3): 406-17, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19918995

RESUMO

The phylogenetic relationship between Australopithecus anamensis and Australopithecus afarensis has been hypothesized as ancestor-descendant. However, the weakest part of this hypothesis has been the absence of fossil samples between 3.6 and 3.9 million years ago. Here we describe new fossil specimens from the Woranso-Mille site in Ethiopia that are directly relevant to this issue. They derive from sediments chronometrically dated to 3.57-3.8 million years ago. The new fossil specimens are largely isolated teeth, partial mandibles, and maxillae, and some postcranial fragments. However, they shed some light on the relationships between Au. anamensis and Au. afarensis. The dental morphology shows closer affinity with Au. anamensis from Allia Bay/Kanapoi (Kenya) and Asa Issie (Ethiopia) than with Au. afarensis from Hadar (Ethiopia). However, they are intermediate in dental and mandibular morphology between Au. anamensis and the older Au. afarensis material from Laetoli. The new fossils lend strong support to the hypothesized ancestor-descendant relationship between these two early Australopithecus species. The Woranso-Mille hominids cannot be unequivocally assigned to either taxon due to their dental morphological intermediacy. This could be an indication that the Kanapoi, Allia Bay, and Asa Issie Au. anamensis is the primitive form of Au. afarensis at Hadar with the Laetoli and Woranso-Mille populations sampling a mosaic of morphological features from both ends. It is particularly difficult to draw a line between Au. anamensis and Au. afarensis in light of the new discoveries from Woranso-Mille. The morphology provides no evidence that Au. afarensis and Au. anamensis represent distinct taxa.


Assuntos
Fósseis , Hominidae/anatomia & histologia , Animais , Cercopithecidae/anatomia & histologia , Etiópia , Sedimentos Geológicos , Geologia , Hominidae/classificação , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia , Paleontologia , Crânio/anatomia & histologia , Dente/anatomia & histologia
10.
Healthc Financ Manage ; 63(7): 32-4, 36, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19588808

RESUMO

In the area of pharmacy services, Kingman Regional's revenue integrity program has enabled the hospital to: Efficiently capture facility-administered pharmaceutical charges at the appropriate rate. Maintain efficient administrative oversight of pharmacy procurement, dispensing, and billing. Automate the transfer of data between various revenue systems within and outside the pharmacy.


Assuntos
Comportamento Cooperativo , Economia Hospitalar/organização & administração , Eficiência Organizacional/economia , Estudos de Casos Organizacionais , Estados Unidos
11.
Technol Cancer Res Treat ; 7(3): 227-33, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18473494

RESUMO

The purpose of this study was to investigate whether helical tomotherapy would better dose-limit growing vertebral ring apophyses during craniospinal radiation as compared to conventional techniques. Four pediatric patients with M0 medulloblastoma received tomotherapy craniospinal radiation (23.4 Gy, 1.8 Gy/fx) by continuous helical delivery of 6 MV photons. Weekly blood counts were monitored. For comparison, conventional craniospinal radiation plans were generated. To assist in tomotherapy planning, a cross-sectional growth study of 52 children and young adults was completed to evaluate spine growth and maturation. Vertebral ring apophyses first fused along the posterolateral body-pedicle synostosis, proceeding circumferentially toward the anterior vertebral body such that the cervical and lumbar vertebrae fused early and mid-thoracic vertebrae fused late. For the four pediatric patients, tomotherapy resulted between 2% and 14% vertebral volume exceeding 23 Gy. Conventional craniospinal radiation predicted between 33% and 44% exceeding 23 Gy. Cumulative body radiation doses exceeding 4 Gy were between 50% and 57% for tomotherapy and between 25% and 37% for conventional craniospinal radiation. Tomotherapy radiation reduced neutrophil, platelet, and erythrocyte hemoglobin levels during treatment. Tomotherapy provides improved dose avoidance to growing vertebrae as compared to conventional craniospinal radiation. However, the long-term effects of tomotherapy dose avoidance on spine growth and large volume low dose radiation in children are not yet known.


Assuntos
Neoplasias Cerebelares/radioterapia , Irradiação Craniana/métodos , Meduloblastoma/radioterapia , Tomografia Computadorizada Espiral , Tomografia Computadorizada por Raios X , Adolescente , Criança , Feminino , Humanos , Masculino , Planejamento da Radioterapia Assistida por Computador , Medula Espinal/efeitos da radiação , Coluna Vertebral/efeitos da radiação
12.
Anat Rec (Hoboken) ; 301(3): 496-514, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29418123

RESUMO

Among living mammals, only the African apes and some anteaters adopt knuckle-walking as their primary locomotor behavior. That Pan and Gorilla both knuckle-walk has been cited as evidence of their common ancestry and a primitive condition for a combined Homo, Pan, and Gorilla clade. Recent research on forelimb ontogeny and anatomy, in addition to recently described hominin fossils, indicate that knuckle-walking was independently acquired after divergence of the Pan and Gorilla lineages. Although the large-bodied, largely suspensory orangutan shares some aspects of the African ape bauplan, it does not regularly knuckle-walk when terrestrial. While many anatomical correlates of knuckle-walking have been identified, a functional explanation of this unusual locomotor pattern has yet to be proposed. Here, we argue that it was adopted by African apes as a means of ameliorating the consequences of repetitive impact loadings on the soft and hard tissues of the forelimb by employing isometric and/or eccentric contraction of antebrachial musculature during terrestrial locomotion. Evidence of this adaptation can be found in the differential size and fiber geometry of the forearm musculature, and differences in torso shape between the knuckle-walking and non-knuckle-walking apes (including humans). We also argue that some osteological features of the carpus and metacarpus that have been identified as adaptations to knuckle-walking are consequences of cartilage remodeling during ontogeny rather than traits limiting motion in the hand and wrist. An understanding of the functional basis of knuckle-walking provides an explanation of the locomotor parallelisms in modern Pan and Gorilla. Anat Rec, 301:496-514, 2018. © 2018 Wiley Periodicals, Inc.


Assuntos
Evolução Biológica , Fósseis , Hominidae/anatomia & histologia , Hominidae/fisiologia , Locomoção/fisiologia , Ossos Metacarpais/fisiologia , Caminhada/fisiologia , Adaptação Fisiológica , Animais , Feminino , Mãos/anatomia & histologia , Mãos/fisiologia , Hominidae/classificação , Masculino , Ossos Metacarpais/anatomia & histologia , Articulação do Punho/anatomia & histologia , Articulação do Punho/fisiologia
13.
PLoS One ; 13(1): e0191703, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29352313

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0183305.].

14.
PLoS One ; 12(8): e0183305, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28827837

RESUMO

OBJECTIVES: This study examines the relationship between spheno-occipital synchondrosis (SOS) closure and puberty onset in a modern American population. It also investigates the timing and the rate of SOS closure in males and females. MATERIALS AND METHODS: The sample includes cross-sectional and longitudinal 3D Cone Beam Computed Tomography (CBCT) scans of 741 individuals (361 males and 380 females) aged 6-20 years. Each CBCT scan is visualized in the mid-sagittal plane, and the spheno-occipital synchondrosis (SOS) is scored as completely open, partially fused, mostly fused, and completely fused. The Menarche commencement is used as an indicator of puberty onset in females. RESULTS: Mean ages of open, partially-fused, mostly-fused, and completely fused SOS were 11.07, 12.95, 14.44, and 16.41 years in males, and 9.75, 11.67, 13.25, and 15.25 in females, respectively. The results show there is a significant association between the SOS closure stage and the commencement of menarche (Fisher's Exact Test p < 0.001). It was found that females had a higher SOS closure rate (38.60%) per year than males at the age of 10 years. The closure rate in males appears slower than females at age 10, but it lasts a longer time, ranging between 22 and 26% per year from age 11 to 14 years. CONCLUSION: There is a significant relationship between puberty onset and SOS closure, suggesting its closure is at least partially affected by systemic, hormonal changes in the growing adolescent. Also, SOS closure occurs at a faster rate and at an earlier age in females compared to males.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Puberdade , Esqueleto/fisiologia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Adulto Jovem
15.
Sci Adv ; 3(11): e1701450, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29152566

RESUMO

The timing of archeological industries in the Levant is central for understanding the spread of modern humans with Upper Paleolithic traditions. We report a high-resolution radiocarbon chronology for Early Upper Paleolithic industries (Early Ahmarian and Levantine Aurignacian) from the newly excavated site of Manot Cave, Israel. The dates confirm that the Early Ahmarian industry was present by 46,000 calibrated years before the present (cal BP), and the Levantine Aurignacian occurred at least between 38,000 and 34,000 cal BP. This timing is consistent with proposed migrations or technological diffusions between the Near East and Europe. Specifically, the Ahmarian could have led to the development of the Protoaurignacian in Europe, and the Aurignacian in Europe could have spread back to the Near East as the Levantine Aurignacian.

16.
Am J Ophthalmol ; 138(4): 674-5, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15488810

RESUMO

PURPOSE: To report the successful use of topical cysteamine formulated from the oral preparation in the treatment of severe photophobia from corneal crystal deposition in cystinosis. DESIGN: Interventional case report. METHODS: Retrospective chart review. RESULTS: An 8-year-old boy with nephropathic cystinosis was experiencing debilitating and worsening photophobia from corneal crystal deposition. Because no parenteral cysteamine was available nationally, the oral capsule was used to formulate an ophthalmic preparation for compassionate use. After 8 months of topical application, the patient has marked improvement of his corneal disease, both subjectively and objectively. CONCLUSIONS: In situations of need, there is a role for the formulation of ophthalmic cysteamine from its oral preparation.


Assuntos
Doenças da Córnea/tratamento farmacológico , Cisteamina/administração & dosagem , Cistinose/tratamento farmacológico , Administração Tópica , Cápsulas , Química Farmacêutica , Criança , Doenças da Córnea/etiologia , Cistinose/complicações , Humanos , Masculino , Soluções Oftálmicas/administração & dosagem , Preparações Farmacêuticas , Fotofobia/tratamento farmacológico , Fotofobia/etiologia , Estudos Retrospectivos
17.
Stud Health Technol Inform ; 88: 387-92, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-15456067

RESUMO

Idiopathic scoliosis is a 3-D deformation affecting the position of the spine in space. The regional deformity has been studied extensively but the local changes have not been widely investigated and this being mainly due to the rarity of anatomical specimens. The objective of this study was to identify a deformation pattern for idiopathic scoliosis. We thus studied one complete scoliotic specimen using a digitizing protocol developed by our research group. The anatomical specimen was selected from the Hamann-Todd Osteology Collection at the Cleveland Natural History Museum, which contains over 1,300 skeletons. We were also able to match this scoliotic specimen with one normal specimen for age, sex, race, height and weight. Each vertebra was measured by taking approximately 200 points on each surface. Parameters for each vertebra were then calculated from these sets of points. Each scoliotic vertebra was then compared with a corresponding normal vertebra of the matched specimen. We present the first findings of these measurements, which show pedicle and posterior elements changes that are thought to be secondary to the scoliotic deformation.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Escoliose/patologia , Coluna Vertebral/patologia , Humanos
18.
PLoS One ; 6(10): e26658, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22028933

RESUMO

The field of evolutionary medicine examines the possibility that some diseases are the result of trade-offs made in human evolution. Spinal fractures are the most common osteoporosis-related fracture in humans, but are not observed in apes, even in cases of severe osteopenia. In humans, the development of osteoporosis is influenced by peak bone mass and strength in early adulthood as well as age-related bone loss. Here, we examine the structural differences in the vertebral bodies (the portion of the vertebra most commonly involved in osteoporosis-related fractures) between humans and apes before age-related bone loss occurs. Vertebrae from young adult humans and chimpanzees, gorillas, orangutans, and gibbons (T8 vertebrae, n = 8-14 per species, male and female, humans: 20-40 years of age) were examined to determine bone strength (using finite element models), bone morphology (external shape), and trabecular microarchitecture (micro-computed tomography). The vertebrae of young adult humans are not as strong as those from apes after accounting for body mass (p<0.01). Human vertebrae are larger in size (volume, cross-sectional area, height) than in apes with a similar body mass. Young adult human vertebrae have significantly lower trabecular bone volume fraction (0.26±0.04 in humans and 0.37±0.07 in apes, mean ± SD, p<0.01) and thinner vertebral shells than apes (after accounting for body mass, p<0.01). Since human vertebrae are more porous and weaker than those in apes in young adulthood (after accounting for bone mass), even modest amounts of age-related bone loss may lead to vertebral fracture in humans, while in apes, larger amounts of bone loss would be required before a vertebral fracture becomes likely. We present arguments that differences in vertebral bone size and shape associated with reduced bone strength in humans is linked to evolutionary adaptations associated with bipedalism.


Assuntos
Evolução Molecular , Osteoporose/complicações , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/genética , Adulto , Animais , Peso Corporal , Força Compressiva , Feminino , Análise de Elementos Finitos , Hominidae/anatomia & histologia , Hominidae/fisiologia , Humanos , Masculino , Tamanho do Órgão , Especificidade da Espécie , Fraturas da Coluna Vertebral/patologia , Fraturas da Coluna Vertebral/fisiopatologia , Coluna Vertebral/anatomia & histologia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/fisiologia , Tomografia Computadorizada por Raios X , Adulto Jovem
19.
Anat Rec (Hoboken) ; 292(8): 1098-106, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19554642

RESUMO

Spontaneous vertebral fractures are a common occurrence in modern humans, yet these fractures are not documented in other hominoids. Differences in vertebral bone strength between humans and apes associated with trabecular bone microarchitecture may contribute to differences in fracture incidence. We used microcomputed tomography to examine trabecular bone microarchitecture in the T8 vertebra of extant young adult hominoids. Scaled volumes of interest from the anterior vertebral body were analyzed at a resolution of 46 microm, and bone volume fraction, trabecular thickness, trabecular number, trabecular separation, structure model index, and degree of anisotropy were compared among species. As body mass increased, so did trabecular thickness, but bone volume fraction, structure model index, and degree of anisotropy were independent of body mass. Bone volume fraction was not significantly different between the species. Degree of anisotropy was not significantly different among the species, suggesting similarity of loading patterns in the T8 vertebra due to similar anatomical and postural relationships within each species' spine. Degree of anisotropy was negatively correlated with bone volume fraction (r(2) = 0.85, P < 0.05) in humans, whereas the apes demonstrated no such relationship. This suggested that less dense human trabecular bone was more preferentially aligned to habitual loading. Furthermore, we theorize that trabeculae in ape thoracic vertebrae would not be expected to become preferentially aligned if bone volume fraction was decreased. The differing relationship between bone volume fraction and degree of anisotropy in humans and apes may cause less dense human bone to be more fragile than less dense ape bone.


Assuntos
Hominidae/anatomia & histologia , Vértebras Torácicas/anatomia & histologia , Vértebras Torácicas/ultraestrutura , Adulto , Animais , Anisotropia , Feminino , Humanos , Masculino , Postura , Fraturas da Coluna Vertebral , Vértebras Torácicas/lesões , Microtomografia por Raio-X
20.
Science ; 326(5949): 72e1-8, 2009 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-19810198

RESUMO

Several elements of the Ardipithecus ramidus foot are preserved, primarily in the ARA-VP-6/500 partial skeleton. The foot has a widely abducent hallux, which was not propulsive during terrestrial bipedality. However, it lacks the highly derived tarsometatarsal laxity and inversion in extant African apes that provide maximum conformity to substrates during vertical climbing. Instead, it exhibits primitive characters that maintain plantar rigidity from foot-flat through toe-off, reminiscent of some Miocene apes and Old World monkeys. Moreover, the action of the fibularis longus muscle was more like its homolog in Old World monkeys than in African apes. Phalangeal lengths were most similar to those of Gorilla. The Ardipithecus gait pattern would thus have been unique among known primates. The last common ancestor of hominids and chimpanzees was therefore a careful climber that retained adaptations to above-branch plantigrady.


Assuntos
Ossos do Pé/anatomia & histologia , Pé/anatomia & histologia , Fósseis , Hominidae/anatomia & histologia , Hominidae/fisiologia , Locomoção , Animais , Evolução Biológica , Etiópia , Marcha , Ossos do Metatarso/anatomia & histologia , Tálus/anatomia & histologia , Ossos do Tarso/anatomia & histologia , Tendões/anatomia & histologia , Falanges dos Dedos do Pé/anatomia & histologia , Caminhada
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