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Over the past three decades, studies of ancient biomolecules-particularly ancient DNA, proteins, and lipids-have revolutionized our understanding of evolutionary history. Though initially fraught with many challenges, today the field stands on firm foundations. Researchers now successfully retrieve nucleotide and amino acid sequences, as well as lipid signatures, from progressively older samples, originating from geographic areas and depositional environments that, until recently, were regarded as hostile to long-term preservation of biomolecules. Sampling frequencies and the spatial and temporal scope of studies have also increased markedly, and with them the size and quality of the data sets generated. This progress has been made possible by continuous technical innovations in analytical methods, enhanced criteria for the selection of ancient samples, integrated experimental methods, and advanced computational approaches. Here, we discuss the history and current state of ancient biomolecule research, its applications to evolutionary inference, and future directions for this young and exciting field.
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DNA Antigo , Evolução Molecular , Animais , Evolução Biológica , Extinção Biológica , Fósseis , Genômica , Humanos , Lipídeos/genética , Paleontologia , Filogenia , Proteínas/genética , ProteômicaRESUMO
Late Pliocene and Early Pleistocene epochs 3.6 to 0.8 million years ago1 had climates resembling those forecasted under future warming2. Palaeoclimatic records show strong polar amplification with mean annual temperatures of 11-19 °C above contemporary values3,4. The biological communities inhabiting the Arctic during this time remain poorly known because fossils are rare5. Here we report an ancient environmental DNA6 (eDNA) record describing the rich plant and animal assemblages of the Kap København Formation in North Greenland, dated to around two million years ago. The record shows an open boreal forest ecosystem with mixed vegetation of poplar, birch and thuja trees, as well as a variety of Arctic and boreal shrubs and herbs, many of which had not previously been detected at the site from macrofossil and pollen records. The DNA record confirms the presence of hare and mitochondrial DNA from animals including mastodons, reindeer, rodents and geese, all ancestral to their present-day and late Pleistocene relatives. The presence of marine species including horseshoe crab and green algae support a warmer climate than today. The reconstructed ecosystem has no modern analogue. The survival of such ancient eDNA probably relates to its binding to mineral surfaces. Our findings open new areas of genetic research, demonstrating that it is possible to track the ecology and evolution of biological communities from two million years ago using ancient eDNA.
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DNA Ambiental , Ecossistema , Ecologia , Fósseis , GroenlândiaRESUMO
During the last glacial-interglacial cycle, Arctic biotas experienced substantial climatic changes, yet the nature, extent and rate of their responses are not fully understood1-8. Here we report a large-scale environmental DNA metagenomic study of ancient plant and mammal communities, analysing 535 permafrost and lake sediment samples from across the Arctic spanning the past 50,000 years. Furthermore, we present 1,541 contemporary plant genome assemblies that were generated as reference sequences. Our study provides several insights into the long-term dynamics of the Arctic biota at the circumpolar and regional scales. Our key findings include: (1) a relatively homogeneous steppe-tundra flora dominated the Arctic during the Last Glacial Maximum, followed by regional divergence of vegetation during the Holocene epoch; (2) certain grazing animals consistently co-occurred in space and time; (3) humans appear to have been a minor factor in driving animal distributions; (4) higher effective precipitation, as well as an increase in the proportion of wetland plants, show negative effects on animal diversity; (5) the persistence of the steppe-tundra vegetation in northern Siberia enabled the late survival of several now-extinct megafauna species, including the woolly mammoth until 3.9 ± 0.2 thousand years ago (ka) and the woolly rhinoceros until 9.8 ± 0.2 ka; and (6) phylogenetic analysis of mammoth environmental DNA reveals a previously unsampled mitochondrial lineage. Our findings highlight the power of ancient environmental metagenomics analyses to advance understanding of population histories and long-term ecological dynamics.
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Biota , DNA Antigo/análise , DNA Ambiental/análise , Metagenômica , Animais , Regiões Árticas , Mudança Climática/história , Bases de Dados Genéticas , Conjuntos de Dados como Assunto , Extinção Biológica , Sedimentos Geológicos , Pradaria , Groenlândia , Haplótipos/genética , Herbivoria/genética , História Antiga , Humanos , Lagos , Mamutes , Mitocôndrias/genética , Perissodáctilos , Pergelissolo , Filogenia , Plantas/genética , Dinâmica Populacional , Chuva , Sibéria , Análise Espaço-Temporal , Áreas AlagadasRESUMO
The initial colonization of the Americas remains a highly debated topic1, and the exact timing of the first arrivals is unknown. The earliest archaeological record of Mexico-which holds a key geographical position in the Americas-is poorly known and understudied. Historically, the region has remained on the periphery of research focused on the first American populations2. However, recent investigations provide reliable evidence of a human presence in the northwest region of Mexico3,4, the Chiapas Highlands5, Central Mexico6 and the Caribbean coast7-9 during the Late Pleistocene and Early Holocene epochs. Here we present results of recent excavations at Chiquihuite Cave-a high-altitude site in central-northern Mexico-that corroborate previous findings in the Americas10-17of cultural evidence that dates to the Last Glacial Maximum (26,500-19,000 years ago)18, and which push back dates for human dispersal to the region possibly as early as 33,000-31,000 years ago. The site yielded about 1,900 stone artefacts within a 3-m-deep stratified sequence, revealing a previously unknown lithic industry that underwent only minor changes over millennia. More than 50 radiocarbon and luminescence dates provide chronological control, and genetic, palaeoenvironmental and chemical data document the changing environments in which the occupants lived. Our results provide new evidence for the antiquity of humans in the Americas, illustrate the cultural diversity of the earliest dispersal groups (which predate those of the Clovis culture) and open new directions of research.
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Migração Humana/história , Camada de Gelo , Altitude , Arqueologia , Teorema de Bayes , Cavernas , Diversidade Cultural , DNA Antigo/análise , História Antiga , Humanos , MéxicoRESUMO
The maritime expansion of Scandinavian populations during the Viking Age (about AD 750-1050) was a far-flung transformation in world history1,2. Here we sequenced the genomes of 442 humans from archaeological sites across Europe and Greenland (to a median depth of about 1×) to understand the global influence of this expansion. We find the Viking period involved gene flow into Scandinavia from the south and east. We observe genetic structure within Scandinavia, with diversity hotspots in the south and restricted gene flow within Scandinavia. We find evidence for a major influx of Danish ancestry into England; a Swedish influx into the Baltic; and Norwegian influx into Ireland, Iceland and Greenland. Additionally, we see substantial ancestry from elsewhere in Europe entering Scandinavia during the Viking Age. Our ancient DNA analysis also revealed that a Viking expedition included close family members. By comparing with modern populations, we find that pigmentation-associated loci have undergone strong population differentiation during the past millennium, and trace positively selected loci-including the lactase-persistence allele of LCT and alleles of ANKA that are associated with the immune response-in detail. We conclude that the Viking diaspora was characterized by substantial transregional engagement: distinct populations influenced the genomic makeup of different regions of Europe, and Scandinavia experienced increased contact with the rest of the continent.
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Fluxo Gênico/genética , Genética Populacional , Genoma Humano/genética , Genômica , Migração Humana/história , Alelos , Conjuntos de Dados como Assunto , Inglaterra , Evolução Molecular , Groenlândia , História Medieval , Humanos , Imunidade/genética , Irlanda , Lactase/genética , Lactase/metabolismo , Masculino , Países Escandinavos e Nórdicos , Seleção Genética , Análise Espaço-Temporal , Adulto JovemRESUMO
BACKGROUND: Allergic rhinitis (AR) is a chronic inflammatory disease of the upper airway, which progresses into allergic asthma (AA) in up to 45% of children. This analysis aimed to investigate clinical and economic benefits of sublingual allergen immunotherapy (SLIT tablets) initiated early in childhood for the treatment of AR by quantifying the long-term reduction in new cases of AA. METHODS: A Markov model was developed to estimate the long-term effects of SLIT tablets on the risk of developing asthma. Key parameters were primarily based on data from the GRAZAX® Asthma Prevention trial and included the age- and treatment-dependent risk of developing AA as well as annual probabilities of progression/remission in AR severity. Healthcare costs were estimated using data from the REACT study. RESULTS: In a modelled cohort of children with moderate-to-severe seasonal AR initiated on SLIT tablets at ages 7 and 12, 24% and 29%, respectively, develop AA during a 20-year period. In comparison, when initiated at age 5, 19% develop AA. Additionally, initiation of SLIT tablets at age 5 is associated with a total healthcare cost of EUR 20,429 per patient, whereas initiation at ages 7 and 12 is associated with, respectively, EUR 21,050 and EUR 22,379 per patient 20 years after AR diagnosis. CONCLUSION: Initiation of SLIT tablets in early childhood is associated with a clinically meaningful and permanent reduction in new cases of AA and lower healthcare costs among children with AR. This finding supports the clinical relevance of initiating SLIT tablets early for children with AR to obtain long-term clinical benefits.
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Asma , Rinite Alérgica Sazonal , Rinite Alérgica , Imunoterapia Sublingual , Pré-Escolar , Humanos , Alérgenos/uso terapêutico , Asma/tratamento farmacológico , Dessensibilização Imunológica , Rinite Alérgica/tratamento farmacológico , Rinite Alérgica Sazonal/prevenção & controle , Rinite Alérgica Sazonal/tratamento farmacológico , Comprimidos , Resultado do Tratamento , Ensaios Clínicos como AssuntoRESUMO
OBJECTIVES: To establish epidemiology, healthcare costs, and labor market attachment in patients with paroxysmal nocturnal hemoglobinuria (Pt-PNH) in Denmark. METHODS: Data were from Statistics Denmark and the Danish Health Data Authority national population registers (2005-2021). Descriptive baseline statistics characterized the Pt-PNH analytic population; ordinary least squares and adjusted Cox proportional hazards regressions measured outcomes in the Pt-PNH versus Danish general population matched comparators. RESULTS: Overall PNH incidence in Denmark was n = 11 during 2007-2009, n = 25 during 2016-2018 and n = 7 during 2019-2020; prevalence increased from n = 13 in 2006 to n = 62 in 2021. Of the overall n = 85 Pt-PNH; n = 24 were treated with complement-5 inhibitors (Pt-C5i) and n = 61 not treated with C5i (Pt-nC5i). Versus respective comparators, all patients had significantly greater annual per-patient costs (from inpatient hospital admissions, outpatient contacts, PNH treatments; indirect costs from lost earnings + transfer payments; post-diagnosis for Pt-PNH and Pt-nC5i, post-treatment initiation for Pt-C5i). The Pt-C5i incurred the greatest healthcare and indirect cost differences (709 119; 152 832, respectively) followed by the Pt-PNH (189 323; 29 159, respectively) and Pt-nC5i (95 548; 4713, respectively). The Pt-PNH versus comparators also had an increased hazard of death (2.71 [95% CI, 1.63 - 4.51]). CONCLUSION: Although a rare disease, PNH is associated with significant patient, healthcare system, and societal burdens in Denmark.
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Hemoglobinúria Paroxística , Humanos , Hemoglobinúria Paroxística/diagnóstico , Hemoglobinúria Paroxística/epidemiologia , Hemoglobinúria Paroxística/terapia , Efeitos Psicossociais da Doença , Atenção à Saúde , Custos de Cuidados de Saúde , Dinamarca/epidemiologiaRESUMO
For thousands of years the Eurasian steppes have been a centre of human migrations and cultural change. Here we sequence the genomes of 137 ancient humans (about 1× average coverage), covering a period of 4,000 years, to understand the population history of the Eurasian steppes after the Bronze Age migrations. We find that the genetics of the Scythian groups that dominated the Eurasian steppes throughout the Iron Age were highly structured, with diverse origins comprising Late Bronze Age herders, European farmers and southern Siberian hunter-gatherers. Later, Scythians admixed with the eastern steppe nomads who formed the Xiongnu confederations, and moved westward in about the second or third century BC, forming the Hun traditions in the fourth-fifth century AD, and carrying with them plague that was basal to the Justinian plague. These nomads were further admixed with East Asian groups during several short-term khanates in the Medieval period. These historical events transformed the Eurasian steppes from being inhabited by Indo-European speakers of largely West Eurasian ancestry to the mostly Turkic-speaking groups of the present day, who are primarily of East Asian ancestry.
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Povo Asiático/genética , Genoma Humano/genética , Pradaria , Filogenia , População Branca/genética , Ásia/etnologia , Europa (Continente)/etnologia , Fazendeiros/história , História Antiga , Migração Humana/história , HumanosRESUMO
with In this Article, Angela M. Taravella and Melissa A. Wilson Sayres have been added to the author list (associated with: School of Life Sciences, Center for Evolution and Medicine, The Biodesign Institute, Arizona State University, Tempe, AZ, USA). The author list and Author Information section have been corrected online.
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Over the past few decades, there has been a growing demand for genome analysis of ancient human remains. Destructive sampling is increasingly difficult to obtain for ethical reasons, and standard methods of breaking the skull to access the petrous bone or sampling remaining teeth are often forbidden for curatorial reasons. However, most ancient humans carried head lice and their eggs abound in historical hair specimens. Here we show that host DNA is protected by the cement that glues head lice nits to the hair of ancient Argentinian mummies, 1,500-2,000 years old. The genetic affinities deciphered from genome-wide analyses of this DNA inform that this population migrated from north-west Amazonia to the Andes of central-west Argentina; a result confirmed using the mitochondria of the host lice. The cement preserves ancient environmental DNA of the skin, including the earliest recorded case of Merkel cell polyomavirus. We found that the percentage of human DNA obtained from nit cement equals human DNA obtained from the tooth, yield 2-fold compared with a petrous bone, and 4-fold to a bloodmeal of adult lice a millennium younger. In metric studies of sheaths, the length of the cement negatively correlates with the age of the specimens, whereas hair linear distance between nit and scalp informs about the environmental conditions at the time before death. Ectoparasitic lice sheaths can offer an alternative, nondestructive source of high-quality ancient DNA from a variety of host taxa where bones and teeth are not available and reveal complementary details of their history.
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DNA Ambiental , Pediculus , Animais , Genoma Humano , Estudo de Associação Genômica Ampla , Humanos , Recém-Nascido , Pediculus/genética , CrânioRESUMO
BACKGROUND: Lung cancer (LC) is the leading cause of cancer deaths worldwide. Several new treatments have become available in recent decades, but little research exists on the impact of these on productivity, early retirement and survival for LC patients and their spouses. This study evaluates the effect of new medicines on productivity, early retirement and survival for LC patients and their spouses. METHODS: Data from the period 1 January 2004-31 December 2018 were collected from complete Danish registers. LC cases diagnosed before approval of first targeted therapy (19 June 2006, Before patients) were compared with those who received at least one new cancer treatment, diagnosed after this date (After patients). Subgroup analyses based on cancer stage, and epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) mutation were conducted. Linear regression and cox regression were used to estimate the outcomes including productivity, unemployment, early retirement, and mortality. Spouses of Before and After patients were compared on earnings, sick leave, early retirement, and healthcare utilisation. RESULTS: The study population comprised of 4,350 patient (2,175 After/2,175 Before). Patients who received new treatments had a significantly reduced risk of death (Hazard ratio = 0.76, Confidence interval: 0.71 - 0.82) and reduced risk of early retirement (Hazard ratio: 0.54, Confidence interval: 0.38 - 0.79). No significant differences in earnings, unemployment, or sick leave were found. Spouses of Before patients had a higher cost of healthcare services after diagnosis compared to spouses of After patients. For productivity, early retirement and sick leave, no significant differences were found between the spouse groups. CONCLUSION: Patients who received innovative new treatments had reduced risk of death and reduced risk of early retirement. Spouses of LC patients who received new treatments had lower healthcare costs in the years following diagnosis. All findings indicate that recipients of new treatments had reduced burden of illness.
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Emprego , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/diagnóstico , Aposentadoria , Estadiamento de Neoplasias , Dinamarca/epidemiologiaRESUMO
PURPOSE: Sym013 contains six humanized monoclonal antibodies that bind to non-overlapping epitopes on three human epidermal growth factor receptors (HER1-3). Preclinical studies suggested Sym013 strongly suppresses growth of multiple epithelial tumors. This is a first-in-human study exploring safety and efficacy of Sym013 in patients with advanced epithelial malignancies. METHODS: Dose escalation used single-patient cohorts until the stopping rule was met, followed by 3 + 3 design. Dose levels planned were: 1, 2, 4, 6, 9, 12, 15, and 18 mg/kg. Treatment cycles were 28 days with imaging every eight weeks. Serum samples were collected at multiple time points for assessment of pharmacokinetics and development of anti-drug antibodies. RESULTS: Thirty-two patients were enrolled with multiple solid tumors, most common being colorectal cancer (CRC; 10/32, 31%). Due to mucositis, rash, and diarrhea at 4 mg/kg once-weekly, dosing was changed to biweekly (Q2W). Mandatory prophylaxis was added due to Grade 3 infusion-related reaction and oral mucositis at 9 mg/kg Q2W. The 15 mg/kg Q2W cohort was enrolling when the study was terminated for business reasons. Most common adverse events were skin (81%) and gastrointestinal (75%) disorders, including dermatitis/rash, stomatitis, and diarrhea. One patient with CRC achieved a partial response; 12 patients with varied malignancies had stable disease. CONCLUSION: During the conduct of the study, management of frequent infusion-related reactions, skin toxicities, and mucosal disorders, which are indicative of HER inhibition, necessitated multiple protocol amendments. The investigators, in concert with the Sponsor, agreed that achieving a tolerated regimen with acceptable target saturation was unlikely. TRIAL REGISTRY: www. CLINICALTRIALS: gov ; NCT02906670 (September 20, 2016).
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Antineoplásicos , Exantema , Neoplasias Epiteliais e Glandulares , Neoplasias , Anticorpos Monoclonais/efeitos adversos , Antineoplásicos/efeitos adversos , Diarreia/induzido quimicamente , Exantema/induzido quimicamente , Humanos , Dose Máxima Tolerável , Neoplasias/metabolismo , Neoplasias Epiteliais e Glandulares/induzido quimicamente , Neoplasias Epiteliais e Glandulares/tratamento farmacológicoRESUMO
During the Last Glacial Maximum, continental ice sheets isolated Beringia (northeast Siberia and northwest North America) from unglaciated North America. By around 15 to 14 thousand calibrated radiocarbon years before present (cal. kyr bp), glacial retreat opened an approximately 1,500-km-long corridor between the ice sheets. It remains unclear when plants and animals colonized this corridor and it became biologically viable for human migration. We obtained radiocarbon dates, pollen, macrofossils and metagenomic DNA from lake sediment cores in a bottleneck portion of the corridor. We find evidence of steppe vegetation, bison and mammoth by approximately 12.6 cal. kyr bp, followed by open forest, with evidence of moose and elk at about 11.5 cal. kyr bp, and boreal forest approximately 10 cal. kyr bp. Our findings reveal that the first Americans, whether Clovis or earlier groups in unglaciated North America before 12.6 cal. kyr bp, are unlikely to have travelled by this route into the Americas. However, later groups may have used this north-south passageway.
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Migração Animal , Migração Humana/história , Camada de Gelo , Animais , Bison/fisiologia , DNA/análise , Cervos/fisiologia , Florestas , Fósseis , Genômica , Sedimentos Geológicos/química , História Antiga , Humanos , Mamutes/fisiologia , Modelos Teóricos , América do Norte , Pólen , Datação Radiométrica , SibériaRESUMO
We describe a local surrogate model for use in conjunction with global structure search methods. The model follows the Gaussian approximation potential formalism and is based on the smooth overlap of atomic positions descriptor with sparsification in terms of a reduced number of local environments using mini-batch k-means. The model is implemented in the Atomistic Global Optimization X framework and used as a partial replacement of the local relaxations in basin hopping structure search. The approach is shown to be robust for a wide range of atomistic systems, including molecules, nanoparticles, surface supported clusters, and surface thin films. The benefits in a structure search context of a local surrogate model are demonstrated. This includes the ability to benefit from transfer learning from smaller systems as well as the possibility to perform concurrent multi-stoichiometry searches.
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To estimate the cost of illness in adult patients with moderate-to-severe atopic dermatitis (AD) a cohort study was conducted identifying Danish citizens (≥ 18 years) diagnosed with AD between 1997 and 2018 in the Danish National Patient Register. Moderate-to-severe AD was defined as ≥3 hospital contacts regarding AD the first year after diagnosis. Each patient with AD was matched to 3 reference individuals through the Central Person Registry. Societal costs included the direct costs for primary-sector visits, inpatient hospitalizations, outpatient contacts, prescription medicine and indirect costs of lost productivity 3 years before and 5 years after the index date (the study period). A total of 5,245 patients with moderate-to-severe AD were identified. The mean attributable healthcare costs for patients with moderate-to-severe AD were EUR 10,835 (p < 0.0001) during the study period. Moderate-to-severe AD among adults inferred substantial economic burden compared with a group of matched reference individuals.
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Dermatite Atópica , Adulto , Estudos de Coortes , Efeitos Psicossociais da Doença , Dinamarca/epidemiologia , Dermatite Atópica/diagnóstico , Dermatite Atópica/epidemiologia , Dermatite Atópica/terapia , Custos de Cuidados de Saúde , HumanosRESUMO
BACKGROUND: Sym004 is a mixture of two monoclonal antibodies (mAbs), futuximab and modotuximab, targeting non-overlapping epitopes on the epidermal growth factor receptor (EGFR). Previous studies have shown that Sym004 is more efficient at inducing internalization and degradation of EGFR than individual components, which translates into superior cancer cell inhibition. We investigated whether Sym004 induces removal of EGFRvIII and if this removal translates into tumor growth inhibition in hard-to-treat glioblastomas (GBMs) harboring the mutated, constitutively active EGFR variant III (EGFRvIII). METHODS: To address this question, we tested the effect of Sym004 versus cetuximab in eight patient-derived GBM xenograft models expressing either wild-type EGFR (EGFRwt) and/or mutant EGFRvIII. All models were tested as both subcutaneous and orthotopic intracranial xenograft models. RESULTS: In vitro studies demonstrated that Sym004 internalized and removed EGFRvIII more efficiently than mAbs, futuximab, modotuximab, and cetuximab. Removal of EGFRvIII by Sym004 translated into significant in vivo anti-tumor activity in all six EGFRvIII xenograft models. Furthermore, the anti-tumor activity of Sym004 in vivo was superior to that of its individual components, futuximab and modotuximab, suggesting a clear synergistic effect of the mAbs in the mixture. CONCLUSION: These results demonstrate the broad activity of Sym004 in patient-derived EGFRvIII-expressing GBM xenograft models and provide a clear rationale for clinical evaluation of Sym004 in EGFRvIII-positive adult GBM patients.