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1.
Nat Rev Genet ; 25(2): 83-103, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37723347

RESUMEN

Denisovans, a group of now extinct humans who lived in Eastern Eurasia in the Middle and Late Pleistocene, were first identified from DNA sequences just over a decade ago. Only ten fragmentary remains from two sites have been attributed to Denisovans based entirely on molecular information. Nevertheless, there has been great interest in using genetic data to understand Denisovans and their place in human history. From the reconstruction of a single high-quality genome, it has been possible to infer their population history, including events of admixture with other human groups. Additionally, the identification of Denisovan DNA in the genomes of present-day individuals has provided insights into the timing and routes of dispersal of ancient modern humans into Asia and Oceania, as well as the contributions of archaic DNA to the physiology of present-day people. In this Review, we synthesize more than a decade of research on Denisovans, reconcile controversies and summarize insights into their population history and phenotype. We also highlight how our growing knowledge about Denisovans has provided insights into our own evolutionary history.


Asunto(s)
Hominidae , Hombre de Neandertal , Animales , Humanos , Hombre de Neandertal/genética , Evolución Biológica , ADN , Investigación Genética , Genoma Humano
2.
Nature ; 610(7932): 519-525, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36261548

RESUMEN

Genomic analyses of Neanderthals have previously provided insights into their population history and relationship to modern humans1-8, but the social organization of Neanderthal communities remains poorly understood. Here we present genetic data for 13 Neanderthals from two Middle Palaeolithic sites in the Altai Mountains of southern Siberia: 11 from Chagyrskaya Cave9,10 and 2 from Okladnikov Cave11-making this one of the largest genetic studies of a Neanderthal population to date. We used hybridization capture to obtain genome-wide nuclear data, as well as mitochondrial and Y-chromosome sequences. Some Chagyrskaya individuals were closely related, including a father-daughter pair and a pair of second-degree relatives, indicating that at least some of the individuals lived at the same time. Up to one-third of these individuals' genomes had long segments of homozygosity, suggesting that the Chagyrskaya Neanderthals were part of a small community. In addition, the Y-chromosome diversity is an order of magnitude lower than the mitochondrial diversity, a pattern that we found is best explained by female migration between communities. Thus, the genetic data presented here provide a detailed documentation of the social organization of an isolated Neanderthal community at the easternmost extent of their known range.


Asunto(s)
Hombre de Neandertal , Animales , Femenino , Humanos , Cuevas , Genoma/genética , Hibridación Genética , Hombre de Neandertal/genética , Siberia , ADN Mitocondrial/genética , Cromosoma Y/genética , Masculino , Familia , Homocigoto
3.
Nature ; 595(7867): 399-403, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34163072

RESUMEN

Denisova Cave in southern Siberia is the type locality of the Denisovans, an archaic hominin group who were related to Neanderthals1-4. The dozen hominin remains recovered from the deposits also include Neanderthals5,6 and the child of a Neanderthal and a Denisovan7, which suggests that Denisova Cave was a contact zone between these archaic hominins. However, uncertainties persist about the order in which these groups appeared at the site, the timing and environmental context of hominin occupation, and the association of particular hominin groups with archaeological assemblages5,8-11. Here we report the analysis of DNA from 728 sediment samples that were collected in a grid-like manner from layers dating to the Pleistocene epoch. We retrieved ancient faunal and hominin mitochondrial (mt)DNA from 685 and 175 samples, respectively. The earliest evidence for hominin mtDNA is of Denisovans, and is associated with early Middle Palaeolithic stone tools that were deposited approximately 250,000 to 170,000 years ago; Neanderthal mtDNA first appears towards the end of this period. We detect a turnover in the mtDNA of Denisovans that coincides with changes in the composition of faunal mtDNA, and evidence that Denisovans and Neanderthals occupied the site repeatedly-possibly until, or after, the onset of the Initial Upper Palaeolithic at least 45,000 years ago, when modern human mtDNA is first recorded in the sediments.


Asunto(s)
Cuevas , ADN Antiguo/análisis , Sedimentos Geológicos/química , Hominidae/genética , Animales , Arqueología , ADN Mitocondrial/análisis , ADN Mitocondrial/genética , Fósiles , Historia Antigua , Hombre de Neandertal/genética , Siberia
4.
Nature ; 565(7741): 640-644, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30700871

RESUMEN

Denisova Cave in the Siberian Altai (Russia) is a key site for understanding the complex relationships between hominin groups that inhabited Eurasia in the Middle and Late Pleistocene epoch. DNA sequenced from human remains found at this site has revealed the presence of a hitherto unknown hominin group, the Denisovans1,2, and high-coverage genomes from both Neanderthal and Denisovan fossils provide evidence for admixture between these two populations3. Determining the age of these fossils is important if we are to understand the nature of hominin interaction, and aspects of their cultural and subsistence adaptations. Here we present 50 radiocarbon determinations from the late Middle and Upper Palaeolithic layers of the site. We also report three direct dates for hominin fragments and obtain a mitochondrial DNA sequence for one of them. We apply a Bayesian age modelling approach that combines chronometric (radiocarbon, uranium series and optical ages), stratigraphic and genetic data to calculate probabilistically the age of the human fossils at the site. Our modelled estimate for the age of the oldest Denisovan fossil suggests that this group was present at the site as early as 195,000 years ago (at 95.4% probability). All Neanderthal fossils-as well as Denisova 11, the daughter of a Neanderthal and a Denisovan4-date to between 80,000 and 140,000 years ago. The youngest Denisovan dates to 52,000-76,000 years ago. Direct radiocarbon dating of Upper Palaeolithic tooth pendants and bone points yielded the earliest evidence for the production of these artefacts in northern Eurasia, between 43,000 and 49,000 calibrated years before present (taken as AD 1950). On the basis of current archaeological evidence, it may be assumed that these artefacts are associated with the Denisovan population. It is not currently possible to determine whether anatomically modern humans were involved in their production, as modern-human fossil and genetic evidence of such antiquity has not yet been identified in the Altai region.


Asunto(s)
Cuevas , Fósiles , Hominidae , Datación Radiométrica , Animales , Teorema de Bayes , ADN Mitocondrial/genética , Ciervos , Fémur/química , Sedimentos Geológicos/química , Historia Antigua , Hominidae/genética , Humanos , Hombre de Neandertal/genética , Isótopos de Oxígeno , Siberia , Factores de Tiempo , Diente/química
5.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-34969841

RESUMEN

Ancient DNA recovered from Pleistocene sediments represents a rich resource for the study of past hominin and environmental diversity. However, little is known about how DNA is preserved in sediments and the extent to which it may be translocated between archaeological strata. Here, we investigate DNA preservation in 47 blocks of resin-impregnated archaeological sediment collected over the last four decades for micromorphological analyses at 13 prehistoric sites in Europe, Asia, Africa, and North America and show that such blocks can preserve DNA of hominins and other mammals. Extensive microsampling of sediment blocks from Denisova Cave in the Altai Mountains reveals that the taxonomic composition of mammalian DNA differs drastically at the millimeter-scale and that DNA is concentrated in small particles, especially in fragments of bone and feces (coprolites), suggesting that these are substantial sources of DNA in sediments. Three microsamples taken in close proximity in one of the blocks yielded Neanderthal DNA from at least two male individuals closely related to Denisova 5, a Neanderthal toe bone previously recovered from the same layer. Our work indicates that DNA can remain stably localized in sediments over time and provides a means of linking genetic information to the archaeological and ecological records on a microstratigraphic scale.


Asunto(s)
Cuevas , ADN Antiguo , Fósiles , Hominidae/genética , Hombre de Neandertal/genética , Animales
6.
Nature ; 561(7721): 113-116, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30135579

RESUMEN

Neanderthals and Denisovans are extinct groups of hominins that separated from each other more than 390,000 years ago1,2. Here we present the genome of 'Denisova 11', a bone fragment from Denisova Cave (Russia)3 and show that it comes from an individual who had a Neanderthal mother and a Denisovan father. The father, whose genome bears traces of Neanderthal ancestry, came from a population related to a later Denisovan found in the cave4-6. The mother came from a population more closely related to Neanderthals who lived later in Europe2,7 than to an earlier Neanderthal found in Denisova Cave8, suggesting that migrations of Neanderthals between eastern and western Eurasia occurred sometime after 120,000 years ago. The finding of a first-generation Neanderthal-Denisovan offspring among the small number of archaic specimens sequenced to date suggests that mixing between Late Pleistocene hominin groups was common when they met.


Asunto(s)
Hominidae/genética , Hibridación Genética/genética , Hombre de Neandertal/genética , Alelos , Animales , Padre , Femenino , Flujo Génico/genética , Genoma , Genómica , Historia Antigua , Humanos , Masculino , Madres , Factores de Tiempo
7.
Proc Natl Acad Sci U S A ; 117(26): 15132-15136, 2020 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-32546518

RESUMEN

We sequenced the genome of a Neandertal from Chagyrskaya Cave in the Altai Mountains, Russia, to 27-fold genomic coverage. We show that this Neandertal was a female and that she was more related to Neandertals in western Eurasia [Prüfer et al., Science 358, 655-658 (2017); Hajdinjak et al., Nature 555, 652-656 (2018)] than to Neandertals who lived earlier in Denisova Cave [Prüfer et al., Nature 505, 43-49 (2014)], which is located about 100 km away. About 12.9% of the Chagyrskaya genome is spanned by homozygous regions that are between 2.5 and 10 centiMorgans (cM) long. This is consistent with the fact that Siberian Neandertals lived in relatively isolated populations of less than 60 individuals. In contrast, a Neandertal from Europe, a Denisovan from the Altai Mountains, and ancient modern humans seem to have lived in populations of larger sizes. The availability of three Neandertal genomes of high quality allows a view of genetic features that were unique to Neandertals and that are likely to have been at high frequency among them. We find that genes highly expressed in the striatum in the basal ganglia of the brain carry more amino-acid-changing substitutions than genes expressed elsewhere in the brain, suggesting that the striatum may have evolved unique functions in Neandertals.


Asunto(s)
Genoma , Hombre de Neandertal/genética , Animales , Evolución Biológica , Femenino , Fósiles , Regulación de la Expresión Génica , Variación Genética , Humanos , Endogamia , Densidad de Población , Federación de Rusia
8.
Nature ; 534(7606): 200-5, 2016 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-27135931

RESUMEN

Modern humans arrived in Europe ~45,000 years ago, but little is known about their genetic composition before the start of farming ~8,500 years ago. Here we analyse genome-wide data from 51 Eurasians from ~45,000-7,000 years ago. Over this time, the proportion of Neanderthal DNA decreased from 3-6% to around 2%, consistent with natural selection against Neanderthal variants in modern humans. Whereas there is no evidence of the earliest modern humans in Europe contributing to the genetic composition of present-day Europeans, all individuals between ~37,000 and ~14,000 years ago descended from a single founder population which forms part of the ancestry of present-day Europeans. An ~35,000-year-old individual from northwest Europe represents an early branch of this founder population which was then displaced across a broad region, before reappearing in southwest Europe at the height of the last Ice Age ~19,000 years ago. During the major warming period after ~14,000 years ago, a genetic component related to present-day Near Easterners became widespread in Europe. These results document how population turnover and migration have been recurring themes of European prehistory.


Asunto(s)
Cubierta de Hielo , Población Blanca/genética , Población Blanca/historia , Animales , Evolución Biológica , ADN/análisis , ADN/genética , ADN/aislamiento & purificación , Europa (Continente) , Femenino , Efecto Fundador , Genética de Población , Historia Antigua , Migración Humana/historia , Humanos , Masculino , Medio Oriente , Hombre de Neandertal/genética , Filogenia , Dinámica Poblacional , Selección Genética , Análisis de Secuencia de ADN , Factores de Tiempo
9.
Nature ; 520(7546): 216-9, 2015 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-25629628

RESUMEN

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.


Asunto(s)
Cuevas , Fósiles , Filogenia , Cráneo/anatomía & histología , África/etnología , Animales , Europa (Continente)/etnología , Humanos , Israel , Hombre de Neandertal/anatomía & histología , Hombre de Neandertal/fisiología
10.
J Hum Evol ; 147: 102867, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32889336

RESUMEN

The site of Riparo Broion (Vicenza, northeastern Italy) preserves a stratigraphic sequence documenting the Middle-to-Upper Paleolithic transition, in particular the final Mousterian and the Uluzzian cultures. In 2018, a human tooth was retrieved from a late Mousterian level, representing the first human remain ever found from this rock shelter (Riparo Broion 1). Here, we provide the morphological description and taxonomic assessment of Riparo Broion 1 with the support of classic and virtual morphology, 2D and 3D analysis of the topography of enamel thickness, and DNA analysis. The tooth is an exfoliated right upper deciduous canine, and its general morphology and enamel thickness distribution support attribution to a Neanderthal child. Correspondingly, the mitochondrial DNA sequence from Riparo Broion 1 falls within the known genetic variation of Late Pleistocene Neanderthals, in accordance with newly obtained radiocarbon dates that point to approximately 48 ka cal BP as the most likely minimum age for this specimen. The present work describes novel and direct evidence of the late Neanderthal occupation in northern Italy that preceded the marked cultural and technological shift documented by the Uluzzian layers in the archaeological sequence at Riparo Broion. Here, we provide a new full morphological, morphometric, and taxonomic analysis of Riparo Broion 1, in addition to generating the wider reference sample of Neanderthal and modern human upper deciduous canines. This research contributes to increasing the sample of fossil remains from Italy, as well as the number of currently available upper deciduous canines, which are presently poorly documented in the scientific literature.


Asunto(s)
Diente Canino/anatomía & histología , Fósiles/anatomía & histología , Hombre de Neandertal/anatomía & histología , Diente Primario/anatomía & histología , Animales , Italia , Maxilar , Paleodontología
11.
Bioscience ; 69(11): 877-887, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31719710

RESUMEN

Drivers of Late Quaternary megafaunal extinctions are relevant to modern conservation policy in a world of growing human population density, climate change, and faunal decline. Traditional debates tend toward global solutions, blaming either dramatic climate change or dispersals of Homo sapiens to new regions. Inherent limitations to archaeological and paleontological data sets often require reliance on scant, poorly resolved lines of evidence. However, recent developments in scientific technologies allow for more local, context-specific approaches. In the present article, we highlight how developments in five such methodologies (radiocarbon approaches, stable isotope analysis, ancient DNA, ancient proteomics, microscopy) have helped drive detailed analysis of specific megafaunal species, their particular ecological settings, and responses to new competitors or predators, climate change, and other external phenomena. The detailed case studies of faunal community composition, extinction chronologies, and demographic trends enabled by these methods examine megafaunal extinctions at scales appropriate for practical understanding of threats against particular species in their habitats today.

12.
Clin Anat ; 32(1): 84-89, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30198179

RESUMEN

The ratio between the sagittal diameter of the spinal canal and the sagittal diameter of the vertebral body, known as the "Torg ratio", is often used to test for spinal canal narrowing. Here, we investigate this ratio in a large population, consisting of two ethnicities, both sexes and three age groups. Measurements were taken on the dry cervical verterbrae (C3-C7) of 277 individuals using a digital apparatus allowing for the recording of 3D coordinates of a set of landmarks on the vertebral body. Vertebral body and vertebral foramen lengths were compared across the different subgroups. Vertebral body and vertebral foramen lengths differ significantly between males and females and between African Americans and European Americans. With age, the vertebral body length increases while the foramen length does not undergo significant changes. These anatomical differences are reflected in differences in the Torg ratio calculated for the different subgroups. In conclusion, our findings suggest that a hard cutoff on the Torg ratio used to define a pathological narrowing of the cervical spine should be adapted to the population the patients come from. Clin. Anat. 32: 84-89, 2019. © 2018 Wiley Periodicals, Inc.


Asunto(s)
Vértebras Cervicales/anatomía & histología , Negro o Afroamericano/estadística & datos numéricos , Factores de Edad , Femenino , Humanos , Masculino , Valores de Referencia , Factores Sexuales , Población Blanca/estadística & datos numéricos
13.
J Hum Evol ; 107: 86-93, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28526291

RESUMEN

The temporal bone discovered in the 1960s from the Darra-i-Kur cave in Afghanistan is often cited as one of the very few Pleistocene human fossils from Central Asia. Here we report the first direct radiocarbon date for the specimen and the genetic analyses of DNA extracted and sequenced from two areas of the bone. The new radiocarbon determination places the find to ∼4500 cal BP (∼2500 BCE) contradicting an assumed Palaeolithic age of ∼30,000 years, as originally suggested. The DNA retrieved from the specimen originates from a male individual who carried mitochondrial DNA of the modern human type. The petrous part yielded more endogenous ancient DNA molecules than the squamous part of the same bone. Molecular dating of the Darra-i-Kur mitochondrial DNA sequence corroborates the radiocarbon date and suggests that the specimen is younger than previously thought. Taken together, the results consolidate the fact that the human bone is not associated with the Pleistocene-age deposits of Darra-i-Kur; instead it is intrusive, possibly re-deposited from upper levels dating to much later periods (Neolithic). Despite its Holocene age, the Darra-i-Kur specimen is, so far, the first and only ancient human from Afghanistan whose DNA has been sequenced.


Asunto(s)
Fósiles , Datación Radiométrica/métodos , Hueso Temporal , Afganistán , Humanos , Masculino
14.
Int J Legal Med ; 131(4): 1011-1021, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28154923

RESUMEN

INTRODUCTION: The effect of impact tool geometry and soft material covering on bone fracture patterns plays a major role in fracture patterns. However, the literature is nearly void of such studies and only general correlations between the fracture pattern and the mechanism underlying the insult were reported. PURPOSE: The aim of this study is to reveal the association between the geometry of the impact tool and the presence of soft material covering on bone fracture patterns. The Dynatup Model POE 2000 (Instron Co.) low energy pendulum impact machine was utilized to apply impact loading on fresh pig femoral bones (n = 50). The bone clamp shaft was adjusted to position the bone for three-point bending with additional bone compression simulating a situation occurring in pedestrian road traffic accidents. Five different tests using varying impact tool sizes with and without soft interface covering were carried out. RESULTS: A significant positive correlation was found between the fracture features and the impact tool's geometry. Only bones that were damaged by a rounded impact body result in a "false" butterfly fragment; in all other cases where the impact body is flat and wide, double trapezoid fragments are observed in the area of impact. The impacted aspect is the most affected. All fracture line features were significantly greater in bones subjected to an impact by tools without soft covering. With an impact with soft covering, the impacted aspect exhibits numerous unique fracture lines and a fragmented pattern. Our study clearly shows that impact tool geometry and soft material covering markedly affect the fracture pattern.


Asunto(s)
Fémur/lesiones , Ciencias Forenses/instrumentación , Fracturas Óseas/patología , Estrés Mecánico , Animales , Niño , Diseño de Equipo , Fémur/patología , Humanos , Modelos Animales , Porcinos
15.
BMC Musculoskelet Disord ; 18(1): 164, 2017 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-28424050

RESUMEN

BACKGROUND: Degenerative lumbar spinal stenosis (DLSS) is a common health problem in the elderly and usually associated with three-joint complex degeneration. Schmorl's nodes (SNs) are described as vertical herniation of the disc into the vertebral body through a weakened part of the end plate that can lead to disc degeneration. Since SNs can harm the spine unit stability, the association between DLSS and SNs is expected. The aim of this study is to shed light on the relationship between degenerative lumbar spinal stenosis and SNs. METHODS: Two groups of individuals were studied: the first included 165 individuals with DLSS (age range: 40-88, sex ratio: 80 M/85 F) and the second 180 individuals without spinal stenosis related symptoms (age range: 40-99, sex ratio: 90 M/90 F). The presence or absence of SNs on the cranial and caudal end plate surfaces at the lumbosacral region (from L1 to S1 vertebra) was recorded, using CT images (Brilliance 64 Philips Medical System, Cleveland Ohio, thickness of the sections was 1-3 mm and MAS, 80-250). Chi-Square test was taken to compare the prevalence of SNs between the study groups (control and stenosis) by lumbar disc level, for each gender separately. Multivariable logistic regression analysis was also used to determine the association between DLSS and SNs. RESULTS: The prevalence rate of SNs was significantly greater in the stenosis males (L1-2 to L5-S1) and females (L4-5 and L4-S1) compared to their counterparts in the control (P < 0.001). In addition, the presence of SNs in both males and females was found to increase the likelihood for DLSS. CONCLUSIONS: Our results indicate that SNs prevalence is significantly greater in the DLSS group compared to the control. Furthermore, SNs are strongly associated with DLSS.


Asunto(s)
Degeneración del Disco Intervertebral/complicaciones , Degeneración del Disco Intervertebral/epidemiología , Desplazamiento del Disco Intervertebral/complicaciones , Desplazamiento del Disco Intervertebral/epidemiología , Vértebras Lumbares/patología , Región Lumbosacra/patología , Estenosis Espinal/etiología , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Degeneración del Disco Intervertebral/diagnóstico por imagen , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Región Lumbosacra/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Factores Sexuales , Estenosis Espinal/diagnóstico por imagen , Tomografía Computarizada por Rayos X
16.
BMC Musculoskelet Disord ; 17(1): 422, 2016 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-27724897

RESUMEN

BACKGROUND: The condition of paraspinal muscles is known to be associated with some variables such as age, gender, and low back pain. It is generally agreed that these muscles play an important role in the stability and functional movements of the lumbar vertebral column. Although spinal instability has been shown to play an essential role in degenerative lumbar spinal stenosis (DLSS), the role of paraspinal muscles remains elusive. The main purpose of this study was to shed light on the relationship between the condition of paraspinal muscles and symptomatic DLSS. METHODS: Two sample populations were studied. The first included 165 individuals with DLSS (age range: 40-88, sex ratio: 80 M/85 F) and the second 180 individuals without spinal stenosis related symptoms and low back pain (age range: 40-99, sex ratio: 90 M/90 F). Measurements were taken at the middle part of L3 vertebral body, using CT axial images (Philips Brilliance 64). Muscles density was measured in Hounsfield units (HU) using a 50 mm2 circle of the muscle mass at three different locations and the mean density was then calculated. The cross-sectional area (CSA) was also measured using the quantitative CT angiography method. Analysis of Covariance (adjusted for body mass index and age) was performed in order to determine the relationship between the condition of paraspinal muscles and symptomatic DLSS. RESULTS: Individuals in the stenosis group had higher muscle density as compared to the control group. The CSA values for the erector spinae (both sexes) and psoas (males) muscles were significantly greater in the stenosis group as compared to their counterparts in the control group. Additionally, density of multifidus (both sexes) and erector spinae (males) muscles was significantly associated with symptomatic DLSS. CONCLUSIONS: Our results show that individuals with symptomatic DLSS manifest greater paraspinal muscles density and CSA (erector spinae), compared to the control group. Density of multifidus increases the likelihood of symptomatic DLSS.


Asunto(s)
Vértebras Lumbares/diagnóstico por imagen , Músculos Paraespinales/diagnóstico por imagen , Estenosis Espinal/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
17.
Eur Spine J ; 24(10): 2189-95, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25987455

RESUMEN

PURPOSE: Vertebral hemangiomas (VHs) are the most common form of benign tumors in the spine. The aim of this research was to study the prevalence of VHs in the human population, their distribution along the spine and their location in the vertebral body. METHODS: The presence of VHs was assessed in full spine CT scans of 196 adults. Demographic data were gathered from medical records. RESULTS: VHs were present in 26.0% of the individuals studied, a rate significantly higher (χ2=43.338, p<0.001) than the prevalence reported in the literature (10.7%). Multiple VHs (≥2) appeared in 7.2% of the population studied. VHs prevalence is sex-independent, appearing in 28.6% of females and 23.5% of males (χ2=0.663, p=0.416); and age-dependent: the mean age of affected individuals (65.8 years) was significantly higher (p<0.001) than unaffected individuals (56.2 years). VH size was also age-dependent (p=0.023). No vertebra was significantly more prone to be affected by a hemangioma. T11 and T12 show the highest prevalence of VHs (3.57% of vertebrae affected). VHs were found in similar percentages in the anterior and posterior parts of the vertebral body (52.8 vs. 47.2%, respectively); and at its center and periphery (50.1 and 49.9%, respectively). VHs usually appeared at mid-height of the vertebral body or slightly higher. CONCLUSIONS: The reported prevalence of VHs is dependent on the demographic structure of the population studied, the size of the VHs and the method used to identify them. Overall, the phenomenon is more frequent than usually reported. VHs may appear at all vertebral levels and in all areas of the vertebral body.


Asunto(s)
Hemangioma/epidemiología , Neoplasias de la Columna Vertebral/epidemiología , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
18.
Curr Biol ; 33(3): 423-433.e5, 2023 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-36638796

RESUMEN

The peopling history of North Asia remains largely unexplored due to the limited number of ancient genomes analyzed from this region. Here, we report genome-wide data of ten individuals dated to as early as 7,500 years before present from three regions in North Asia, namely Altai-Sayan, Russian Far East, and the Kamchatka Peninsula. Our analysis reveals a previously undescribed Middle Holocene Siberian gene pool in Neolithic Altai-Sayan hunter-gatherers as a genetic mixture between paleo-Siberian and ancient North Eurasian (ANE) ancestries. This distinctive gene pool represents an optimal source for the inferred ANE-related population that contributed to Bronze Age groups from North and Inner Asia, such as Lake Baikal hunter-gatherers, Okunevo-associated pastoralists, and possibly Tarim Basin populations. We find the presence of ancient Northeast Asian (ANA) ancestry-initially described in Neolithic groups from the Russian Far East-in another Neolithic Altai-Sayan individual associated with different cultural features, revealing the spread of ANA ancestry ∼1,500 km further to the west than previously observed. In the Russian Far East, we identify 7,000-year-old individuals that carry Jomon-associated ancestry indicating genetic links with hunter-gatherers in the Japanese archipelago. We also report multiple phases of Native American-related gene flow into northeastern Asia over the past 5,000 years, reaching the Kamchatka Peninsula and central Siberia. Our findings highlight largely interconnected population dynamics throughout North Asia from the Early Holocene onward.


Asunto(s)
Pool de Genes , Genoma Humano , Humanos , Historia Antigua , Recién Nacido , Asia , Federación de Rusia , Siberia , Migración Humana , Genética de Población
19.
Sci Rep ; 12(1): 14528, 2022 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-36008437

RESUMEN

Paleogenomic research can elucidate the evolutionary history of human and faunal populations. Although the Levant is a key land-bridge between Africa and Eurasia, thus far, relatively little ancient DNA data has been generated from this region, since DNA degrades faster in warm climates. As sediments can be a source of ancient DNA, we analyzed 33 sediment samples from different sedimentological contexts in the Paleolithic layers of Sefunim Cave (Israel). Four contained traces of ancient Cervidae and Hyaenidae mitochondrial DNA. Dating by optical luminescence and radiocarbon indicates that the DNA comes from layers between 30,000 and 70,000 years old, surpassing theoretical expectations regarding the longevity of DNA deposited in such a warm environment. Both identified taxa are present in the zooarchaeological record of the site but have since gone extinct from the region, and a geoarchaeological study suggests little movement of the sediments after their deposition, lending further support to our findings. We provide details on the local conditions in the cave, which we hypothesize were particularly conducive to the long-term preservation of DNA-information that will be pertinent for future endeavors aimed at recovering ancient DNA from the Levant and other similarly challenging contexts.


Asunto(s)
ADN Antiguo , Hyaenidae , Animales , Arqueología , Evolución Biológica , Cuevas , Fósiles , Humanos , Recién Nacido , Israel
20.
J Quat Sci ; 37(2): 235-256, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35874301

RESUMEN

The Middle to Upper Palaeolithic transition, between 50 000 and 40 000 years ago, is a period of important ecological and cultural changes. In this framework, the Rock Shelter of Uluzzo C (Apulia, southern Italy) represents an important site due to Late Mousterian and Uluzzian evidence preserved in its stratigraphic sequence. Here, we present the results of a multidisciplinary analysis performed on the materials collected between 2016 and 2018 from the Uluzzian stratigraphic units (SUs) 3, 15 and 17. The analysis involved lithic technology, use-wear, zooarchaeology, ancient DNA of sediments and palaeoproteomics, completed by quartz single-grain optically stimulated luminescence dating of the cave sediments. The lithic assemblage is characterized by a volumetric production and a debitage with no or little management of the convexities (by using the bipolar technique), with the objective to produce bladelets and flakelets. The zooarchaeological study found evidence of butchery activity and of the possible exploitation of marine resources, while drawing a picture of a patchy landscape, composed of open forests and dry open environments surrounding the shelter. Ancient mitochondrial DNA from two mammalian taxa were recovered from the sediments. Preliminary zooarchaeology by mass spectrometry results are consistent with ancient DNA and zooarchaeological taxonomic information, while further palaeoproteomics investigations are ongoing. Our new data from the re-discovery of the Uluzzo C Rock Shelter represent an important contribution to better understand the meaning of the Uluzzian in the context of the Middle/Upper Palaeolithic transition in south-eastern Italy.

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