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2.
Nature ; 577(7790): 381-385, 2020 01.
Article in English | MEDLINE | ID: mdl-31853068

ABSTRACT

Homo erectus is the founding early hominin species of Island Southeast Asia, and reached Java (Indonesia) more than 1.5 million years ago1,2. Twelve H. erectus calvaria (skull caps) and two tibiae (lower leg bones) were discovered from a bone bed located about 20 m above the Solo River at Ngandong (Central Java) between 1931 and 19333,4, and are of the youngest, most-advanced form of H. erectus5-8. Despite the importance of the Ngandong fossils, the relationship between the fossils, terrace fill and ages have been heavily debated9-14. Here, to resolve the age of the Ngandong evidence, we use Bayesian modelling of 52 radiometric age estimates to establish-to our knowledge-the first robust chronology at regional, valley and local scales. We used uranium-series dating of speleothems to constrain regional landscape evolution; luminescence, 40argon/39argon (40Ar/39Ar) and uranium-series dating to constrain the sequence of terrace evolution; and applied uranium-series and uranium series-electron-spin resonance (US-ESR) dating to non-human fossils to directly date our re-excavation of Ngandong5,15. We show that at least by 500 thousand years ago (ka) the Solo River was diverted into the Kendeng Hills, and that it formed the Solo terrace sequence between 316 and 31 ka and the Ngandong terrace between about 140 and 92 ka. Non-human fossils recovered during the re-excavation of Ngandong date to between 109 and 106 ka (uranium-series minimum)16 and 134 and 118 ka (US-ESR), with modelled ages of 117 to 108 thousand years (kyr) for the H. erectus bone bed, which accumulated during flood conditions3,17. These results negate the extreme ages that have been proposed for the site and solidify Ngandong as the last known occurrence of this long-lived species.


Subject(s)
Hominidae , Animals , Biological Evolution , Fossils , Indonesia , Leg Bones , Skull , Time Factors
3.
Nat Ecol Evol ; 3(7): 999-1000, 2019 07.
Article in English | MEDLINE | ID: mdl-31209288

Subject(s)
Hominidae , Animals
4.
Sci Adv ; 4(12): eaau5064, 2018 12.
Article in English | MEDLINE | ID: mdl-30585290

ABSTRACT

After European colonization, the ancestral remains of Indigenous people were often collected for scientific research or display in museum collections. For many decades, Indigenous people, including Native Americans and Aboriginal Australians, have fought for their return. However, many of these remains have no recorded provenance, making their repatriation very difficult or impossible. To determine whether DNA-based methods could resolve this important problem, we sequenced 10 nuclear genomes and 27 mitogenomes from ancient pre-European Aboriginal Australians (up to 1540 years before the present) of known provenance and compared them to 100 high-coverage contemporary Aboriginal Australian genomes, also of known provenance. We report substantial ancient population structure showing strong genetic affinities between ancient and contemporary Aboriginal Australian individuals from the same geographic location. Our findings demonstrate the feasibility of successfully identifying the origins of unprovenanced ancestral remains using genomic methods.


Subject(s)
Body Remains , Forensic Anthropology , Genetics, Population , Genome, Human , Alleles , Australia , DNA, Mitochondrial , Databases, Genetic , Genomics/methods , Humans , Phylogeny
6.
Mol Biol Evol ; 35(3): 623-630, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-29220488

ABSTRACT

Recent studies have reported evidence suggesting that portions of contemporary human genomes introgressed from archaic hominin populations went to high frequencies due to positive selection. However, no study to date has specifically addressed the postintrogression population dynamics of these putative cases of adaptive introgression. Here, for the first time, we specifically define cases of immediate adaptive introgression (iAI) in which archaic haplotypes rose to high frequencies in humans as a result of a selective sweep that occurred shortly after the introgression event. We define these cases as distinct from instances of selection on standing introgressed variation (SI), in which an introgressed haplotype initially segregated neutrally and subsequently underwent positive selection. Using a geographically diverse data set, we report novel cases of selection on introgressed variation in living humans and shortlist among these cases those whose selective sweeps are more consistent with having been the product of iAI rather than SI. Many of these novel inferred iAI haplotypes have potential biological relevance, including three that contain immune-related genes in West Siberians, South Asians, and West Eurasians. Overall, our results suggest that iAI may not represent the full picture of positive selection on archaically introgressed haplotypes in humans and that more work needs to be done to analyze the role of SI in the archaic introgression landscape of living humans.

7.
J Can Chiropr Assoc ; 62(3): 130-142, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30662067

ABSTRACT

OBJECTIVES: To: 1) develop/adapt and validate an instrument to measure patient safety attitudes and opinions of community-based spinal manipulative therapy (SMT) providers; 2) implement the instrument; and 3) compare results among healthcare professions. METHODS: A review of the literature and content validation were used for the survey development. Community-based chiropractors and physiotherapists in 4 Canadian provinces were invited. RESULTS: The Agency for Healthcare Research and Quality's (AHRQ) Medical Office Survey on Patient Safety Culture was the preferred instrument. The survey was modified and validated, measuring 14 patient safety dimensions. 276 SMT providers volunteered to respond to the survey. Generally, SMT providers had similar or better patient safety dimension scores compared to the AHRQ 2016 medical offices database. DISCUSSION: We developed the first instrument measuring patient safety attitudes and opinions of community-based SMT providers. This instrument provides understanding of SMT providers' opinions and attitudes on patient safety and identifies potential areas for improvement.


OBJECTIFS: 1) Élaborer/adapter et valider un instrument servant à évaluer les attitudes à l'égard de la sécurité du patient et les opinions des praticiens effectuant des manipulations vertébrales (MV); 2) adopter cet instrument; et 3) comparer les résultats obtenus entre les professionnels de la santé. MÉTHODOLOGIE: Pour élaborer le sondage, on a revu la littérature, on a validé le contenu et on a invité des chiropraticiens et des physiothérapeutes de quatre provinces canadiennes à participer. RÉSULTATS: Le Medical Office Survey on Patient Safety Culture de l'Agency for Healthcare Research and Quality's (AHRQ) était l'instrument préféré. Le sondage a été modifié et validé et a servi à mesurer 14 aspects de la sécurité du patient. 276 professionnels effectuant des MV ont accepté de répondre au sondage. En règle générale, les cotes obtenues chez les professionnels effectuant des MV pour ce qui des aspects de la sécurité étaient comparables ou meilleurs que celles des professionnels de la santé enregistrés dans la base de données de 2016 de l'AHRQ. DISCUSSION: On a élaboré le premier instrument servant à évaluer les attitudes à l'égard de la sécurité et les opinions des praticiens effectuant des MV dans une collectivité. Cet instrument permet de comprendre les opinions et les attitudes à l'égard de la sécurité du patient des professionnels effectuant des MV et de cerner les aspects qui pourraient être améliorés.

8.
Nature ; 538(7624): 238-242, 2016 Oct 13.
Article in English | MEDLINE | ID: mdl-27654910

ABSTRACT

High-coverage whole-genome sequence studies have so far focused on a limited number of geographically restricted populations, or been targeted at specific diseases, such as cancer. Nevertheless, the availability of high-resolution genomic data has led to the development of new methodologies for inferring population history and refuelled the debate on the mutation rate in humans. Here we present the Estonian Biocentre Human Genome Diversity Panel (EGDP), a dataset of 483 high-coverage human genomes from 148 populations worldwide, including 379 new genomes from 125 populations, which we group into diversity and selection sets. We analyse this dataset to refine estimates of continent-wide patterns of heterozygosity, long- and short-distance gene flow, archaic admixture, and changes in effective population size through time as well as for signals of positive or balancing selection. We find a genetic signature in present-day Papuans that suggests that at least 2% of their genome originates from an early and largely extinct expansion of anatomically modern humans (AMHs) out of Africa. Together with evidence from the western Asian fossil record, and admixture between AMHs and Neanderthals predating the main Eurasian expansion, our results contribute to the mounting evidence for the presence of AMHs out of Africa earlier than 75,000 years ago.


Subject(s)
Genome, Human/genetics , Genomics , Human Migration/history , Racial Groups/genetics , Africa/ethnology , Animals , Asia , Datasets as Topic , Estonia , Europe , Fossils , Gene Flow , Genetics, Population , Heterozygote , History, Ancient , Humans , Native Hawaiian or Other Pacific Islander/genetics , Neanderthals/genetics , New Guinea , Population Dynamics
9.
Nature ; 538(7624): 207-214, 2016 Oct 13.
Article in English | MEDLINE | ID: mdl-27654914

ABSTRACT

The population history of Aboriginal Australians remains largely uncharacterized. Here we generate high-coverage genomes for 83 Aboriginal Australians (speakers of Pama-Nyungan languages) and 25 Papuans from the New Guinea Highlands. We find that Papuan and Aboriginal Australian ancestors diversified 25-40 thousand years ago (kya), suggesting pre-Holocene population structure in the ancient continent of Sahul (Australia, New Guinea and Tasmania). However, all of the studied Aboriginal Australians descend from a single founding population that differentiated ~10-32 kya. We infer a population expansion in northeast Australia during the Holocene epoch (past 10,000 years) associated with limited gene flow from this region to the rest of Australia, consistent with the spread of the Pama-Nyungan languages. We estimate that Aboriginal Australians and Papuans diverged from Eurasians 51-72 kya, following a single out-of-Africa dispersal, and subsequently admixed with archaic populations. Finally, we report evidence of selection in Aboriginal Australians potentially associated with living in the desert.


Subject(s)
Genome, Human/genetics , Genomics , Native Hawaiian or Other Pacific Islander/genetics , Phylogeny , Racial Groups/genetics , Africa/ethnology , Australia , Datasets as Topic , Desert Climate , Gene Flow , Genetics, Population , History, Ancient , Human Migration/history , Humans , Language , New Guinea , Population Dynamics , Tasmania
11.
Proc Natl Acad Sci U S A ; 113(25): 6892-7, 2016 06 21.
Article in English | MEDLINE | ID: mdl-27274055

ABSTRACT

The publication in 2001 by Adcock et al. [Adcock GJ, et al. (2001) Proc Natl Acad Sci USA 98(2):537-542] in PNAS reported the recovery of short mtDNA sequences from ancient Australians, including the 42,000-y-old Mungo Man [Willandra Lakes Hominid (WLH3)]. This landmark study in human ancient DNA suggested that an early modern human mitochondrial lineage emerged in Asia and that the theory of modern human origins could no longer be considered solely through the lens of the "Out of Africa" model. To evaluate these claims, we used second generation DNA sequencing and capture methods as well as PCR-based and single-primer extension (SPEX) approaches to reexamine the same four Willandra Lakes and Kow Swamp 8 (KS8) remains studied in the work by Adcock et al. Two of the remains sampled contained no identifiable human DNA (WLH15 and WLH55), whereas the Mungo Man (WLH3) sample contained no Aboriginal Australian DNA. KS8 reveals human mitochondrial sequences that differ from the previously inferred sequence. Instead, we recover a total of five modern European contaminants from Mungo Man (WLH3). We show that the remaining sample (WLH4) contains ∼1.4% human DNA, from which we assembled two complete mitochondrial genomes. One of these was a previously unidentified Aboriginal Australian haplotype belonging to haplogroup S2 that we sequenced to a high coverage. The other was a contaminating modern European mitochondrial haplotype. Although none of the sequences that we recovered matched those reported by Adcock et al., except a contaminant, these findings show the feasibility of obtaining important information from ancient Aboriginal Australian remains.


Subject(s)
DNA, Mitochondrial/genetics , Australia , Humans , Likelihood Functions , Phylogeny
13.
Genome Res ; 25(4): 459-66, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25770088

ABSTRACT

It is commonly thought that human genetic diversity in non-African populations was shaped primarily by an out-of-Africa dispersal 50-100 thousand yr ago (kya). Here, we present a study of 456 geographically diverse high-coverage Y chromosome sequences, including 299 newly reported samples. Applying ancient DNA calibration, we date the Y-chromosomal most recent common ancestor (MRCA) in Africa at 254 (95% CI 192-307) kya and detect a cluster of major non-African founder haplogroups in a narrow time interval at 47-52 kya, consistent with a rapid initial colonization model of Eurasia and Oceania after the out-of-Africa bottleneck. In contrast to demographic reconstructions based on mtDNA, we infer a second strong bottleneck in Y-chromosome lineages dating to the last 10 ky. We hypothesize that this bottleneck is caused by cultural changes affecting variance of reproductive success among males.


Subject(s)
Chromosomes, Human, Y/genetics , Evolution, Molecular , Racial Groups/genetics , Base Sequence , DNA, Mitochondrial/genetics , Genetic Variation/genetics , Genetics, Population , Haplotypes/genetics , Humans , Male , Models, Genetic , Phylogeny , Sequence Analysis, DNA
15.
Science ; 346(6213): 1113-8, 2014 Nov 28.
Article in English | MEDLINE | ID: mdl-25378462

ABSTRACT

The origin of contemporary Europeans remains contentious. We obtained a genome sequence from Kostenki 14 in European Russia dating from 38,700 to 36,200 years ago, one of the oldest fossils of anatomically modern humans from Europe. We find that Kostenki 14 shares a close ancestry with the 24,000-year-old Mal'ta boy from central Siberia, European Mesolithic hunter-gatherers, some contemporary western Siberians, and many Europeans, but not eastern Asians. Additionally, the Kostenki 14 genome shows evidence of shared ancestry with a population basal to all Eurasians that also relates to later European Neolithic farmers. We find that Kostenki 14 contains more Neandertal DNA that is contained in longer tracts than present Europeans. Our findings reveal the timing of divergence of western Eurasians and East Asians to be more than 36,200 years ago and that European genomic structure today dates back to the Upper Paleolithic and derives from a metapopulation that at times stretched from Europe to central Asia.


Subject(s)
DNA/genetics , Genome, Human/genetics , White People/genetics , DNA/history , Europe , Fossils , Genomics , History, Ancient , Humans , Male , Siberia , White People/history
16.
PLoS One ; 8(3): e58811, 2013.
Article in English | MEDLINE | ID: mdl-23554931

ABSTRACT

Joint surfaces of limb bones are loaded in compression by reaction forces generated from body weight and musculotendon complexes bridging them. In general, joints of eutherian mammals have regions of high radiodensity subchondral bone that are better at resisting compressive forces than low radiodensity subchondral bone. Identifying similar form-function relationships between subchondral radiodensity distribution and joint load distribution within the marsupial postcranium, in addition to providing a richer understanding of marsupial functional morphology, can serve as a phylogenetic control in evaluating analogous relationships within eutherian mammals. Where commonalities are established across phylogenetic borders, unifying principles in mammalian physiology, morphology, and behavior can be identified. Here, we assess subchondral radiodensity patterns in distal tibiae of several marsupial taxa characterized by different habitual activities (e.g., locomotion). Computed tomography scanning, maximum intensity projection maps, and pixel counting were used to quantify radiodensity in 41 distal tibiae of bipedal (5 species), arboreal quadrupedal (4 species), and terrestrial quadrupedal (5 species) marsupials. Bipeds (Macropus and Wallabia) exhibit more expansive areas of high radiodensity in the distal tibia than arboreal (Dendrolagus, Phascolarctos, and Trichosurus) or terrestrial quadrupeds (Sarcophilus, Thylacinus, Lasiorhinus, and Vombatus), which may reflect the former carrying body weight only through the hind limbs. Arboreal quadrupeds exhibit smallest areas of high radiodensity, though they differ non-significantly from terrestrial quadrupeds. This could indicate slightly more compliant gaits by arboreal quadrupeds compared to terrestrial quadrupeds. The observed radiodensity patterns in marsupial tibiae, though their statistical differences disappear when controlling for phylogeny, corroborate previously documented patterns in primates and xenarthrans, potentially reflecting inferred limb use during habitual activities such as locomotion. Despite the complex nature of factors contributing to joint loads, broad observance of these patterns across joints and across a variety of taxa suggests that subchondral radiodensity can be used as a unifying form-function principle within Mammalia.


Subject(s)
Ankle Joint/physiology , Marsupialia/physiology , Weight-Bearing , Analysis of Variance , Animals , Ankle Joint/anatomy & histology , Bone Density , Marsupialia/anatomy & histology , Phylogeny , Posture
17.
PLoS One ; 8(3): e59170, 2013.
Article in English | MEDLINE | ID: mdl-23527121

ABSTRACT

BACKGROUND: Cervical artery dissection (CAD) and stroke are serious harms that are sometimes associated with cervical spinal manipulation therapy (cSMT). Because of the relative rarity of these adverse events, studying them prospectively is challenging. As a result, systematic review of reports describing these events offers an important opportunity to better understand the relation between adverse events and cSMT. Of note, the quality of the case report literature in this area has not yet been assessed. PURPOSE: 1) To systematically collect and synthesize available reports of CAD that have been associated with cSMT in the literature and 2) assess the quality of these reports. METHODS: A systematic review of the literature was conducted using several databases. All clinical study designs involving CADs associated with cSMT were eligible for inclusion. Included studies were screened by two independent reviewers for the presence/absence of 11 factors considered to be important in understanding the relation between CAD and cSMT. RESULTS: Overall, 43 articles reported 901 cases of CAD and 707 incidents of stroke reported to be associated with cSMT. The most common type of stroke reported was ischemic stroke (92%). Time-to-onset of symptoms was reported most frequently (95%). No single case included all 11 factors. CONCLUSIONS: This study has demonstrated that the literature infrequently reports useful data toward understanding the association between cSMT, CADs and stroke. Improving the quality, completeness, and consistency of reporting adverse events may improve our understanding of this important relation.


Subject(s)
Cervical Vertebrae , Manipulation, Spinal/adverse effects , Vertebral Artery Dissection/etiology , Humans , Research Design/standards , Stroke/etiology , Vertebral Artery Dissection/diagnosis
18.
BMC Musculoskelet Disord ; 11: 29, 2010 Feb 09.
Article in English | MEDLINE | ID: mdl-20144214

ABSTRACT

BACKGROUND: The cervical zygapophyseal joints may be a primary source of pain in up to 60% of individuals with chronic whiplash associated disorders (WAD) and may be a contributing factor for peripheral and centrally mediated pain (sensory hypersensitivity). Sensory hypersensitivity has been associated with a poor prognosis. The purpose of the study was to determine if there is a change in measures indicative of sensory hypersensitivity in patients with chronic WAD grade II following a medial branch block (MBB) procedure in the cervical spine. METHODS: Measures of sensory hypersensitivity were taken via quantitative sensory testing (QST) consisting of pressure pain thresholds (PPT's) and cold pain thresholds (CPT's). In patients with chronic WAD (n = 18), the measures were taken at three sites bilaterally, pre- and post- MBB. Reduced pain thresholds at remote sites have been considered an indicator of central hypersensitivity. A healthy age and gender matched comparison group (n = 18) was measured at baseline. An independent t-test was applied to determine if there were any significant differences between the WAD and normative comparison groups at baseline with respect to cold pain and pressure pain thresholds. A dependent t-test was used to determine whether there were any significant differences between the pre and post intervention cold pain and pressure pain thresholds in the patients with chronic WAD. RESULTS: At baseline, PPT's were decreased at all three sites in the WAD group (p < 0.001). Cold pain thresholds were increased in the cervical spine in the WAD group (p < 0.001). Post-MBB, the WAD group showed significant increases in PPT's at all sites (p < 0.05), and significant decreases in CPT's at the cervical spine (p < 0.001). CONCLUSIONS: The patients with chronic WAD showed evidence of widespread sensory hypersensitivity to mechanical and thermal stimuli. The WAD group revealed decreased sensory hypersensitivity following a decrease in their primary source of pain stemming from the cervical zygapophyseal joints.


Subject(s)
Hyperalgesia/etiology , Hyperalgesia/physiopathology , Nociceptors/physiology , Sensory Receptor Cells/physiology , Whiplash Injuries/complications , Whiplash Injuries/physiopathology , Adult , Cervical Vertebrae/physiopathology , Chronic Disease , Female , Humans , Joint Diseases/complications , Joint Diseases/physiopathology , Male , Middle Aged , Pain Threshold/physiology , Physical Stimulation , Pressure , Temperature
19.
Man Ther ; 10(3): 219-23, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16038857

ABSTRACT

An investigation of intra- and inter-rater reliability anterior atlantodental interval (AADI) measurements was conducted using flexion/extension plain radiographs. Flexion and extension lateral radiographs of individuals investigated for atlantoaxial instability were measured for AADI on three occasions. Intra-rater intraclass correlation coefficients (ICC) were calculated for both flexion (0.99) and extension (0.96). Inter-rater ICCs were 0.93 and 0.84 for flexion and extension, respectively. The AADI measurement proved to be reproducible with a minimal standard of error, between and within raters.


Subject(s)
Arthritis, Rheumatoid/diagnostic imaging , Atlanto-Axial Joint/diagnostic imaging , Joint Instability/diagnostic imaging , Adolescent , Adult , Female , Humans , Male , Middle Aged , Radiography , Reproducibility of Results , Retrospective Studies
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