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1.
J Psychosom Res ; 167: 111183, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36801662

RESUMO

OBJECTIVE: The COVID-19 pandemic posed new challenges for integrated health care worldwide. Our study aimed to describe newly implemented structures and procedures of psychosocial consultation and liaison (CL) services in Europe and beyond, and to highlight emerging needs for co-operation. METHODS: Cross-sectional online survey from June to October 2021, using a self-developed 25-item questionnaire in four language versions (English, French, Italian, German). Dissemination was via national professional societies, working groups, and heads of CL services. RESULTS: Of the participating 259 CL services from Europe, Iran, and parts of Canada, 222 reported COVID-19 related psychosocial care (COVID-psyCare) in their hospital. Among these, 86.5% indicated that specific COVID-psyCare co-operation structures had been established. 50.8% provided specific COVID-psyCare for patients, 38.2% for relatives, and 77.0% for staff. Over half of the time resources were invested for patients. About a quarter of the time was used for staff, and these interventions, typically associated with the liaison function of CL services, were reported as most useful. Concerning emerging needs, 58.1% of the CL services providing COVID-psyCare expressed wishes for mutual information exchange and support, and 64.0% suggested specific changes or improvements that they considered essential for the future. CONCLUSION: Over 80% of participating CL services established specific structures to provide COVID-psyCare for patients, their relatives, or staff. Mostly, resources were committed to patient care and specific interventions were largely implemented for staff support. Future development of COVID-psyCare warrants intensified intra- and inter-institutional exchange and co-operation.


Assuntos
COVID-19 , Serviços de Saúde Mental , Humanos , Hospitais Gerais , Estudos Transversais , Pandemias , Europa (Continente) , Encaminhamento e Consulta
2.
Anim Microbiome ; 3(1): 30, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879261

RESUMO

BACKGROUND: Infectious diseases cause significant production losses in aquaculture every year. Since the gut microbiota plays an essential role in regulating the host immune system, health and physiology, altered gut microbiota compositions are often associated with a diseased status. However, few studies have examined the association between disease severity and degree of gut dysbiosis, especially when the gut is not the site of the primary infection. Moreover, there is a lack of knowledge on whether bath treatment with formalin, a disinfectant commonly used in aquaculture to treat external infections, might affect the gut microbiome as a consequence of formalin ingestion. Here we investigate, through 16S rRNA gene metabarcoding, changes in the distal gut microbiota composition of a captive-reared cohort of 80 Atlantic salmon (Salmo salar L.), in consequence of an external bacterial skin infection due to a natural outbreak and subsequent formalin treatment. RESULTS: We identified Tenacibaculum dicentrarchi as the causative disease pathogen and we show that the distal gut of diseased salmon presented a different composition from that of healthy individuals. A new, yet undescribed, Mycoplasma genus characterized the gut of healthy salmon, while in the sick fish we observed an increase in terms of relative abundance of Aliivibrio sp., a strain regarded as opportunistic. We also noticed a positive correlation between fish weight and Mycoplasma sp. relative abundance, potentially indicating a beneficial effect for its host. Moreover, we observed that the gut microbiota of fish treated with formalin was more similar to those of sick fish than healthy ones. CONCLUSIONS: We conclude that external Tenacibaculum infections have the potential of indirectly affecting the host gut microbiota. As such, treatment optimization procedures should account for that. Formalin treatment is not an optimal solution from a holistic perspective, since we observe an altered gut microbiota in the treated fish. We suggest its coupling with a probiotic treatment aimed at re-establishing a healthy community. Lastly, we have observed a positive correlation of Mycoplasma sp. with salmon health and weight, therefore we encourage further investigations towards its potential utilization as a biomarker for monitoring health in salmon and potentially other farmed fish species.

3.
Data Brief ; 31: 105721, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32490085

RESUMO

The spotted seahorse, Hippocampus kuda population is exponentially decreasing globally due to habitat loss contributed by massive coastal urbanization as well as its large exploitation for Chinese herbal medicine. Genomic data would be highly useful to improve biomonitoring of seahorse populations in Malaysia via the usage of non-invasive approaches such as water environmental DNA. Here we report the first complete mitogenome of two H. kuda individuals originating from Malaysia, generated using BGISEQ-500RS sequencer. The lengths of both mitogenomes are 16,529bp, consisting of 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and a control region. The overall base composition was 32.46% for A, 29.40% for T, 14.73% for G and 23.41% for C with AT rich features (61.86%). The gene organization of Malaysian H. kuda were similar to that of most teleost species. A phylogenetic analysis of the genome against mtDNA data from other Hippocampus species showed that Malaysian H. kuda samples clustered with H. capensis, H. reidi and H. kuda. Notably however, analysis of the data using BLASTn revealed they had 99.18% similarity to H. capensis, and only 97.66% to H. kuda and H. reidi, which are all part of the unresolved H. kuda complex. The mitogenomes are deposited in Genbank under the accession number MT221436 (HK1) and MT221436 (HK2).

4.
Nat Plants ; 5(6): 595-603, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31182840

RESUMO

The Eurasian grapevine (Vitis vinifera) has long been important for wine production as well as being a food source. Despite being clonally propagated, modern cultivars exhibit great morphological and genetic diversity, with thousands of varieties described in historic and contemporaneous records. Through historical accounts, some varieties can be traced to the Middle Ages, but the genetic relationships between ancient and modern vines remain unknown. We present target-enriched genome-wide sequencing data from 28 archaeological grape seeds dating to the Iron Age, Roman era and medieval period. When compared with domesticated and wild accessions, we found that the archaeological samples were closely related to western European cultivars used for winemaking today. We identified seeds with identical genetic signatures present at different Roman sites, as well as seeds sharing parent-offspring relationships with varieties grown today. Furthermore, we discovered that one seed dated to ~1100 CE was a genetic match to 'Savagnin Blanc', providing evidence for 900 years of uninterrupted vegetative propagation.


Assuntos
Produtos Agrícolas/genética , Variação Genética , Vitis/genética , Arqueologia , Produtos Agrícolas/história , França , História Antiga , Polimorfismo de Nucleotídeo Único , Sementes/genética , Vinho
5.
Front Microbiol ; 10: 697, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024486

RESUMO

Although there is an extensive tradition of research into the microbes that underlie the winemaking process, much remains to be learnt. We combined the high-throughput sequencing (HTS) tools of metabarcoding and metagenomics, to characterize how microbial communities of Riesling musts sampled at four different vineyards, and their subsequent spontaneously fermented derivatives, vary. We specifically explored community variation relating to three points: (i) how microbial communities vary by vineyard; (ii) how community biodiversity changes during alcoholic fermentation; and (iii) how microbial community varies between musts that successfully complete alcoholic fermentation and those that become 'stuck' in the process. Our metabarcoding data showed a general influence of microbial composition at the vineyard level. Two of the vineyards (4 and 5) had strikingly a change in the differential abundance of Metschnikowia. We therefore additionally performed shotgun metagenomic sequencing on a subset of the samples to provide preliminary insights into the potential relevance of this observation, and used the data to both investigate functional potential and reconstruct draft genomes (bins). At these two vineyards, we also observed an increase in non-Saccharomycetaceae fungal functions, and a decrease in bacterial functions during the early fermentation stage. The binning results yielded 11 coherent bins, with both vineyards sharing the yeast bins Hanseniaspora and Saccharomyces. Read recruitment and functional analysis of this data revealed that during fermentation, a high abundance of Metschnikowia might serve as a biocontrol agent against bacteria, via a putative iron depletion pathway, and this in turn could help Saccharomyces dominate the fermentation. During alcoholic fermentation, we observed a general decrease in biodiversity in both the metabarcoding and metagenomic data. Unexpected Micrococcus behavior was observed in vineyard 4 according to metagenomic analyses based on reference-based read mapping. Analysis of open reading frames using these data showed an increase of functions assigned to class Actinobacteria in the end of fermentation. Therefore, we hypothesize that bacteria might sit-and-wait until Saccharomyces activity slows down. Complementary approaches to annotation instead of relying a single database provide more coherent information true species. Lastly, our metabarcoding data enabled us to identify a relationship between stuck fermentations and Starmerella abundance. Given that robust chemical analysis indicated that although the stuck samples contained residual glucose, all fructose had been consumed, we hypothesize that this was because fructophilic Starmerella, rather than Saccharomyces, dominated these fermentations. Overall, our results showcase the different ways in which metagenomic analyses can improve our understanding of the wine alcoholic fermentation process.

6.
J Dairy Sci ; 99(9): 7602-7611, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27289153

RESUMO

Veal calves at the age of 4 to 6 mo often experience problems with glucose homeostasis, as indicated by postprandial hyperglycemia, hyperinsulinemia, and insulin resistance. It is not clear to what extent the ontogenetic development of calves or the feeding strategy [e.g., prolonged milk replacer (MR) feeding] contribute to this pathology. The objective of this study was therefore to analyze effects of MR feeding, weaning, and supplementation of short-chain fructo-oligosaccharides (FOS) on the development of glucose homeostasis and insulin sensitivity in calves during the first 3 mo of life. Thirty male Holstein-Friesian calves (18±0.7 d of age) were assigned to 1 of 3 dietary treatments: the control (CON) group received MR only, the FOS group received MR with the addition of short-chain FOS, and the solid feed (SF) group was progressively weaned to SF. The CON and FOS calves received an amount of MR, which gradually increased (from 400 to 1,400 g/d) during the 71-d trial period. For the SF calves, the amount of MR increased from 400 to 850 g/d at d 30, and then gradually decreased, until completely weaned to only SF at d 63. The change in whole body insulin sensitivity was assessed by intravenous glucose tolerance tests. Milk tolerance tests were performed twice to assess changes in postprandial blood glucose, insulin, and nonesterified fatty acid responses. Whole-body insulin sensitivity was high at the start (16.7±1.6×10(-4) [µU/mL](-1)), but decreased with age to 4.2±0.6×10(-4) [µU/mL](-1) at the end of the trial. The decrease in insulin sensitivity was most pronounced (~70%) between d 8 and 29 of the trial. Dietary treatments did not affect the decrease in insulin sensitivity. For CON and FOS calves, the postprandial insulin response was 3-fold higher at the end of the trial than at the start, whereas the glucose response remained similar. The SF calves, however, showed pronounced hyperglycemia and hyperinsulinemia at the end of the trial, although weaning did not affect insulin sensitivity. We conclude that whole body insulin sensitivity decreases by 75% in calves during the first 3 mo of life. Weaning or supplementation of short-chain FOS does not affect this age-related decline in insulin sensitivity. Glucose homeostasis is not affected by supplementation of short-chain FOS in young calves, whereas postprandial responses of glucose and insulin to a MR meal strongly increase after weaning.


Assuntos
Glicemia/metabolismo , Bovinos/fisiologia , Dieta/veterinária , Resistência à Insulina , Oligossacarídeos/metabolismo , Desmame , Fatores Etários , Ração Animal/análise , Animais , Suplementos Nutricionais/análise , Homeostase , Masculino , Oligossacarídeos/administração & dosagem
7.
Philos Trans R Soc Lond B Biol Sci ; 370(1660): 20130373, 2015 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-25487325

RESUMO

The European Neolithization process started around 12 000 years ago in the Near East. The introduction of agriculture spread north and west throughout Europe and a key question has been if this was brought about by migrating individuals, by an exchange of ideas or a by a mixture of these. The earliest farming evidence in Scandinavia is found within the Funnel Beaker Culture complex (Trichterbecherkultur, TRB) which represents the northernmost extension of Neolithic farmers in Europe. The TRB coexisted for almost a millennium with hunter-gatherers of the Pitted Ware Cultural complex (PWC). If migration was a substantial part of the Neolithization, even the northerly TRB community would display a closer genetic affinity to other farmer populations than to hunter-gatherer populations. We deep-sequenced the mitochondrial hypervariable region 1 from seven farmers (six TRB and one Battle Axe complex, BAC) and 13 hunter-gatherers (PWC) and authenticated the sequences using postmortem DNA damage patterns. A comparison with 124 previously published sequences from prehistoric Europe shows that the TRB individuals share a close affinity to Central European farmer populations, and that they are distinct from hunter-gatherer groups, including the geographically close and partially contemporary PWC that show a close affinity to the European Mesolithic hunter-gatherers.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Migração Humana/história , Agricultura/história , Sequência de Bases , Biologia Computacional , Primers do DNA/genética , DNA Mitocondrial/história , Fluxo Gênico , Genética Populacional , Sequenciamento de Nucleotídeos em Larga Escala , História Antiga , Humanos , Modelos Genéticos , Dados de Sequência Molecular , Dinâmica Populacional , Reação em Cadeia da Polimerase em Tempo Real , Suécia
8.
Animal ; 8(10): 1643-52, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25231281

RESUMO

In milk-fed calves, quantification of the milk that enters the rumen (ruminal milk volume, RMV) because of malfunction of the esophageal groove reflex may explain part of the variability observed between animals in their growth performance. The RMV can directly be quantified by adding an indigestible marker to the diet and measuring its recovery in the rumen at slaughter, but this technique cannot be repeated in time in the same animal. The objective of the study was to evaluate three indirect methods for estimating RMV. The first method was based on the assumption that ruminal drinking delays and limits acetaminophen appearance in blood after ingestion of milk supplemented with acetaminophen. The second method was based on a negative linear relationship between RMV and urinary recovery of non-metabolizable monosaccharides (3-O-methylglucose, l-rhamnose and d-xylose) added to the milk, owing to rumen fermentation. In the third method, RMV was calculated as the difference between total milk intake and the increase in abomasal milk volume (AMV) at feeding, measured through ultrasonography shortly after feeding, or estimated from the mathematical extrapolation of AMV to feeding time, based on consecutive measurements. These methods were tested in three experiments where calves (n=22, 10 and 13) were bucket fed or partly tube fed (i.e. by inserting milk replacer into the rumen via a tube to mimic ruminal drinking). In addition, Co-EDTA and Cr-EDTA were used as an indigestible marker in one experiment to trace bucket-fed or tube-fed milk replacer, respectively, to measure RMV. The relationship between AMV measured by ultrasonography and AMV measured at slaughter improved when kinetics of AMV were extrapolated to the time of slaughter by mathematical modeling (error between predicted and measured AMV equaled 0.49 l). With this technique, RMV during feeding averaged 17% and 24% of intake in Experiments 2 and 3, respectively. Plasma acetaminophen kinetics and recovery of non-metabolizable monosaccharides in urine were partly associated with ruminal drinking, but these techniques are not considered quantitatively accurate without further information of rumen degradation and absorption. The recovery of indigestible marker measured at slaughter gave a quantitative estimate of RMV (2% in Experiment 3), but improper measurement of emptying rate of fluid from the rumen may lead to underestimation. In conclusion, measuring changes in AMV by ultrasonography, in response to milk feeding, was the most promising indirect method to quantify RMV in veal calves.


Assuntos
Bovinos/fisiologia , Leite/metabolismo , Abomaso/metabolismo , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais , Ingestão de Alimentos , Fermentação , Rúmen/metabolismo
9.
Mol Biol Evol ; 31(6): 1414-20, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24577840

RESUMO

The plant pathogen Phytophthora infestans emerged in Europe in 1845, triggering the Irish potato famine and massive European potato crop losses that continued until effective fungicides were widely employed in the 20th century. Today the pathogen is ubiquitous, with more aggressive and virulent strains surfacing in recent decades. Recently, complete P. infestans mitogenome sequences from 19th-century herbarium specimens were shown to belong to a unique lineage (HERB-1) predicted to be rare or extinct in modern times. We report 44 additional P. infestans mitogenomes: four from 19th-century Europe, three from 1950s UK, and 37 from modern populations across the New World. We use phylogenetic analyses to identify the HERB-1 lineage in modern populations from both Mexico and South America, and to demonstrate distinct mitochondrial haplotypes were present in 19th-century Europe, with this lineage initially diversifying 75 years before the first reports of potato late blight.


Assuntos
DNA Mitocondrial/análise , Phytophthora infestans/classificação , Phytophthora infestans/isolamento & purificação , Doenças das Plantas/parasitologia , Solanum tuberosum/parasitologia , América , Teorema de Bayes , Evolução Molecular , História do Século XIX , Irlanda , Filogenia , Filogeografia , Phytophthora infestans/genética , Doenças das Plantas/história , Inanição/história , Reino Unido
10.
Nat Commun ; 4: 2172, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23863894

RESUMO

Responsible for the Irish potato famine of 1845-49, the oomycete pathogen Phytophthora infestans caused persistent, devastating outbreaks of potato late blight across Europe in the 19th century. Despite continued interest in the history and spread of the pathogen, the genome of the famine-era strain remains entirely unknown. Here we characterize temporal genomic changes in introduced P. infestans. We shotgun sequence five 19th-century European strains from archival herbarium samples--including the oldest known European specimen, collected in 1845 from the first reported source of introduction. We then compare their genomes to those of extant isolates. We report multiple distinct genotypes in historical Europe and a suite of infection-related genes different from modern strains. At virulence-related loci, several now-ubiquitous genotypes were absent from the historical gene pool. At least one of these genotypes encodes a virulent phenotype in modern strains, which helps explain the 20th century's episodic replacements of European P. infestans lineages.


Assuntos
Evolução Molecular , Genoma Fúngico , Phytophthora infestans/genética , Phytophthora infestans/patogenicidade , Doenças das Plantas/microbiologia , Solanum tuberosum/microbiologia , Inanição/microbiologia , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , História do Século XIX , Humanos , Irlanda , Fenótipo , Filogenia , Phytophthora infestans/classificação , Doenças das Plantas/história , Inanição/história , Virulência
11.
Curr Biol ; 22(16): 1494-9, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22748318

RESUMO

The genetic background of the European Mesolithic and the extent of population replacement during the Neolithic is poorly understood, both due to the scarcity of human remains from that period and the inherent methodological difficulties of ancient DNA research. However, advances in sequencing technologies are both increasing data yields and providing supporting evidence for data authenticity, such as nucleotide misincorporation patterns. We use these methods to characterize both the mitochondrial DNA genome and generate shotgun genomic data from two exceptionally well-preserved 7,000-year-old Mesolithic individuals from La Braña-Arintero site in León (Northwestern Spain). The mitochondria of both individuals are assigned to U5b2c1, a haplotype common among the small number of other previously studied Mesolithic individuals from Northern and Central Europe. This suggests a remarkable genetic uniformity and little phylogeographic structure over a large geographic area of the pre-Neolithic populations. Using Approximate Bayesian Computation, a model of genetic continuity from Mesolithic to Neolithic populations is poorly supported. Furthermore, analyses of 1.34% and 0.53% of their nuclear genomes, containing about 50,000 and 20,000 ancestry informative SNPs, respectively, show that these two Mesolithic individuals are not related to current populations from either the Iberian Peninsula or Southern Europe.


Assuntos
DNA Mitocondrial , Fósseis , Genoma Humano , Genoma Mitocondrial , Sequência de Bases , História Antiga , Humanos , Dados de Sequência Molecular , Espanha
12.
Haemophilia ; 18(6): 868-74, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22642565

RESUMO

Multiple factors place adults with haemophilia at risk for depression. Health outcomes can be compromised in depressed patients secondary to increased risk taking behaviour and poor compliance with treatment recommendations. To assess the prevalence and risk factors associated with depression in adult patients with haemophilia treated at a haemophilia treatment centre. Adults with haemophilia were screened for depression during their annual clinic visit using the Patient Health Questionnaire 9 (PHQ-9), a validated tool for depression screening in adults. Depression was defined as a PHQ-9 score ≥ 5. Risk factors associated with depression were collected by chart review and correlated with depression scores. A total of 41 adult patients consented to the study and 37% met criteria for depression. Fifty-three per cent of patients with depression reported moderate to severe symptoms of depression (PHQ-9 score >10). Seventy-six per cent of patients with depression reported suffering functional impairment due to their depressive symptoms. Lack of social support and unemployment were significantly associated with higher PHQ-9 scores (P = 0.04 and P = 0.01 respectively). Adult patients with haemophilia have a high prevalence of depression. The addition of depression screening to the comprehensive care of adults with haemophilia may result in improved overall health outcomes and treatment adherence.


Assuntos
Transtornos Herdados da Coagulação Sanguínea/complicações , Depressão/epidemiologia , Atividades Cotidianas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Depressão/complicações , Emprego , Infecções por HIV/complicações , Hepatite C/complicações , Humanos , Pessoa de Meia-Idade , Prevalência , Qualidade de Vida , Fatores de Risco , Apoio Social , Inquéritos e Questionários , Adulto Jovem
13.
Mol Ecol ; 21(8): 1989-2003, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22590727

RESUMO

Although ancient DNA from sediments (sedaDNA) has been used to investigate past ecosystems, the approach has never been directly compared with the traditional methods of pollen and macrofossil analysis. We conducted a comparative survey of 18 ancient permafrost samples spanning the Late Pleistocene (46-12.5 thousand years ago), from the Taymyr Peninsula in northern Siberia. The results show that pollen, macrofossils and sedaDNA are complementary rather than overlapping and, in combination, reveal more detailed information on plant palaeocommunities than can be achieved by each individual approach. SedaDNA and macrofossils share greater overlap in plant identifications than with pollen, suggesting that sedaDNA is local in origin. These two proxies also permit identification to lower taxonomic levels than pollen, enabling investigation into temporal changes in species composition and the determination of indicator species to describe environmental changes. Combining data from all three proxies reveals an area continually dominated by a mosaic vegetation of tundra-steppe, pioneer and wet-indicator plants. Such vegetational stability is unexpected, given the severe climate changes taking place in the Northern Hemisphere during this time, with changes in average annual temperatures of >22 °C. This may explain the abundance of ice-age mammals such as horse and bison in Taymyr Peninsula during the Pleistocene and why it acted as a refugium for the last mainland woolly mammoth. Our finding reveals the benefits of combining sedaDNA, pollen and macrofossil for palaeovegetational reconstruction and adds to the increasing evidence suggesting large areas of the Northern Hemisphere remained ecologically stable during the Late Pleistocene.


Assuntos
DNA de Plantas/análise , Fósseis , Sedimentos Geológicos/química , Gelo , Pólen , Ecossistema , História Antiga , Plantas/classificação , Plantas/genética , Sibéria
14.
Science ; 336(6080): 466-9, 2012 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-22539720

RESUMO

The farming way of life originated in the Near East some 11,000 years ago and had reached most of the European continent 5000 years later. However, the impact of the agricultural revolution on demography and patterns of genomic variation in Europe remains unknown. We obtained 249 million base pairs of genomic DNA from ~5000-year-old remains of three hunter-gatherers and one farmer excavated in Scandinavia and find that the farmer is genetically most similar to extant southern Europeans, contrasting sharply to the hunter-gatherers, whose distinct genetic signature is most similar to that of extant northern Europeans. Our results suggest that migration from southern Europe catalyzed the spread of agriculture and that admixture in the wake of this expansion eventually shaped the genomic landscape of modern-day Europe.


Assuntos
Agricultura/história , Variação Genética , Genoma Humano , População Branca/genética , Sepultamento , DNA Mitocondrial/genética , Demografia , Emigração e Imigração/história , Haplótipos , História Antiga , Humanos , Polimorfismo de Nucleotídeo Único , Dinâmica Populacional , Análise de Componente Principal , Análise de Sequência de DNA , Suécia , População Branca/história
15.
BMC Evol Biol ; 12: 35, 2012 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-22429664

RESUMO

BACKGROUND: House mice (Mus musculus) are commensals of humans and therefore their phylogeography can reflect human colonization and settlement patterns. Previous studies have linked the distribution of house mouse mitochondrial (mt) DNA clades to areas formerly occupied by the Norwegian Vikings in Norway and the British Isles. Norwegian Viking activity also extended further westwards in the North Atlantic with the settlement of Iceland, short-lived colonies in Greenland and a fleeting colony in Newfoundland in 1000 AD. Here we investigate whether house mouse mtDNA sequences reflect human history in these other regions as well. RESULTS: House mice samples from Iceland, whether from archaeological Viking Age material or from modern-day specimens, had an identical mtDNA haplotype to the clade previously linked with Norwegian Vikings. From mtDNA and microsatellite data, the modern-day Icelandic mice also share the low genetic diversity shown by their human hosts on Iceland. Viking Age mice from Greenland had an mtDNA haplotype deriving from the Icelandic haplotype, but the modern-day Greenlandic mice belong to an entirely different mtDNA clade. We found no genetic association between modern Newfoundland mice and the Icelandic/ancient Greenlandic mice (no ancient Newfoundland mice were available). The modern day Icelandic and Newfoundland mice belong to the subspecies M. m. domesticus, the Greenlandic mice to M. m. musculus. CONCLUSIONS: In the North Atlantic region, human settlement history over a thousand years is reflected remarkably by the mtDNA phylogeny of house mice. In Iceland, the mtDNA data show the arrival and continuity of the house mouse population to the present day, while in Greenland the data suggest the arrival, subsequent extinction and recolonization of house mice--in both places mirroring the history of the European human host populations. If house mice arrived in Newfoundland with the Viking settlers at all, then, like the humans, their presence was also fleeting and left no genetic trace. The continuity of mtDNA haplotype in Iceland over 1000 years illustrates that mtDNA can retain the signature of the ancestral house mouse founders. We also show that, in terms of genetic variability, house mouse populations may also track their host human populations.


Assuntos
Migração Animal , DNA Mitocondrial/genética , Animais , Emigração e Imigração/história , Variação Genética , Groenlândia , História do Século XV , História Antiga , História Medieval , Humanos , Islândia , Camundongos , Repetições de Microssatélites/genética , Terra Nova e Labrador , Filogenia , Especificidade da Espécie
16.
Mol Ecol ; 21(8): 1980-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21951625

RESUMO

Nunataks are isolated bedrocks protruding through ice sheets. They vary in age, but represent island environments in 'oceans' of ice through which organism dispersals and replacements can be studied over time. The J.A.D. Jensen's Nunataks at the southern Greenland ice sheet are the most isolated nunataks on the northern hemisphere - some 30 km from the nearest biological source. They constitute around 2 km(2) of ice-free land that was established in the early Holocene. We have investigated the changes in plant composition at these nunataks using both the results of surveys of the flora over the last 130 years and through reconstruction of the vegetation from the end of the Holocene Thermal Maximum (5528 ± 75 cal year BP) using meta-barcoding of plant DNA recovered from the nunatak sediments (sedaDNA). Our results show that several of the plant species detected with sedaDNA are described from earlier vegetation surveys on the nunataks (in 1878, 1967 and 2009). In 1967, a much higher biodiversity was detected than from any other of the studied periods. While this may be related to differences in sampling efforts for the oldest period, it is not the case when comparing the 1967 and 2009 levels where the botanical survey was exhaustive. As no animals and humans are found on the nunataks, this change in diversity over a period of just 42 years must relate to environmental changes probably being climate-driven. This suggests that even the flora of fairly small and isolated ice-free areas reacts quickly to a changing climate.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Fósseis , Sedimentos Geológicos/química , Camada de Gelo , Plantas/genética , Regiões Árticas , DNA Mitocondrial/análise , DNA de Plantas , Groenlândia , História do Século XIX , História do Século XX , História do Século XXI , História Antiga , Gelo , Especificidade da Espécie
17.
Nature ; 479(7373): 359-64, 2011 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-22048313

RESUMO

Despite decades of research, the roles of climate and humans in driving the dramatic extinctions of large-bodied mammals during the Late Quaternary period remain contentious. Here we use ancient DNA, species distribution models and the human fossil record to elucidate how climate and humans shaped the demographic history of woolly rhinoceros, woolly mammoth, wild horse, reindeer, bison and musk ox. We show that climate has been a major driver of population change over the past 50,000 years. However, each species responds differently to the effects of climatic shifts, habitat redistribution and human encroachment. Although climate change alone can explain the extinction of some species, such as Eurasian musk ox and woolly rhinoceros, a combination of climatic and anthropogenic effects appears to be responsible for the extinction of others, including Eurasian steppe bison and wild horse. We find no genetic signature or any distinctive range dynamics distinguishing extinct from surviving species, emphasizing the challenges associated with predicting future responses of extant mammals to climate and human-mediated habitat change.


Assuntos
Biota , Mudança Climática/história , Extinção Biológica , Atividades Humanas/história , Mamíferos/fisiologia , Animais , Teorema de Bayes , Bison , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Europa (Continente) , Fósseis , Variação Genética , Geografia , História Antiga , Cavalos , Humanos , Mamíferos/genética , Mamutes , Dados de Sequência Molecular , Dinâmica Populacional , Rena , Sibéria , Especificidade da Espécie , Fatores de Tempo
18.
Nature ; 463(7282): 757-62, 2010 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-20148029

RESUMO

We report here the genome sequence of an ancient human. Obtained from approximately 4,000-year-old permafrost-preserved hair, the genome represents a male individual from the first known culture to settle in Greenland. Sequenced to an average depth of 20x, we recover 79% of the diploid genome, an amount close to the practical limit of current sequencing technologies. We identify 353,151 high-confidence single-nucleotide polymorphisms (SNPs), of which 6.8% have not been reported previously. We estimate raw read contamination to be no higher than 0.8%. We use functional SNP assessment to assign possible phenotypic characteristics of the individual that belonged to a culture whose location has yielded only trace human remains. We compare the high-confidence SNPs to those of contemporary populations to find the populations most closely related to the individual. This provides evidence for a migration from Siberia into the New World some 5,500 years ago, independent of that giving rise to the modern Native Americans and Inuit.


Assuntos
Criopreservação , Extinção Biológica , Genoma Humano/genética , Inuíte/genética , Emigração e Imigração/história , Genética Populacional , Genômica , Genótipo , Groenlândia , Cabelo , História Antiga , Humanos , Masculino , Fenótipo , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Análise de Sequência de DNA , Sibéria/etnologia
19.
Curr Biol ; 19(20): 1758-62, 2009 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-19781941

RESUMO

The driving force behind the transition from a foraging to a farming lifestyle in prehistoric Europe (Neolithization) has been debated for more than a century [1-3]. Of particular interest is whether population replacement or cultural exchange was responsible [3-5]. Scandinavia holds a unique place in this debate, for it maintained one of the last major hunter-gatherer complexes in Neolithic Europe, the Pitted Ware culture [6]. Intriguingly, these late hunter-gatherers existed in parallel to early farmers for more than a millennium before they vanished some 4,000 years ago [7, 8]. The prolonged coexistence of the two cultures in Scandinavia has been cited as an argument against population replacement between the Mesolithic and the present [7, 8]. Through analysis of DNA extracted from ancient Scandinavian human remains, we show that people of the Pitted Ware culture were not the direct ancestors of modern Scandinavians (including the Saami people of northern Scandinavia) but are more closely related to contemporary populations of the eastern Baltic region. Our findings support hypotheses arising from archaeological analyses that propose a Neolithic or post-Neolithic population replacement in Scandinavia [7]. Furthermore, our data are consistent with the view that the eastern Baltic represents a genetic refugia for some of the European hunter-gatherer populations.


Assuntos
Agricultura/história , Emigração e Imigração/história , Antropologia Física , DNA Mitocondrial/química , Variação Genética , História Antiga , Humanos , Países Escandinavos e Nórdicos
20.
Recent Pat CNS Drug Discov ; 3(3): 200-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18991809

RESUMO

Small molecule modulators of neural stem cell (NSC) differentiation might potentially be developed into orally administered neurogenic drugs to treat neurodegenerative diseases including Alzheimer's disease. New technologies developed for the study of NSC culture, proliferation and differentiation have enabled the establishment of screening platforms to identify small molecules with neurogenic activity. Recent patents claim novel small molecules identified from screening collections that stimulate or otherwise regulate stem cell differentiation and neurogenesis. Several patents claim newly discovered NSC differentiation modulating activity of previously marketed drugs suggesting perhaps a previously unknown mechanism of action of these drugs and/or implicating the target enzyme and receptor pathways as key players in neurogenesis. This relatively new area of research into small molecule modulators of neurogenesis is reviewed and recent patents claiming small molecule neurogenic compounds, potentially orally administered CNS regenerative therapies are summarized.


Assuntos
Neurogênese/efeitos dos fármacos , Animais , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , PPAR gama/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos
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