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1.
J Am Heart Assoc ; : e019243, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33821688

RESUMO

Background NT-proBNP (N-terminal pro-B-type natriuretic peptide) is widely used to diagnose and manage patients with heart failure. We aimed to investigate associations between NT-proBNP levels and development of global and regional myocardial impairment, dyssynchrony, and risk of developing myocardial scar over time. Methods and Results We included 2416 adults (45-84 years) without baseline clinical cardiovascular disease from MESA (Multi-Ethnic Study of Atherosclerosis). NT-proBNP was assessed at baseline (2000-2002). Cardiac magnetic resonance-measured left ventricular parameters were assessed at baseline and year 10 (2010-2012). Tagged cardiac magnetic resonance and myocardial dyssynchrony were assessed. We used linear and logistic regression models to study the relationships between quartiles of NT-proBNP levels and outcome variables. Left ventricular parameters decreased over time. After 10-year follow-up and adjusting for cardiovascular disease risk factors, people in the highest quartile had significantly greater decline in left ventricular ejection fraction (-1.60%; 95% CI, -2.26 to -0.94; P<0.01) and smaller decline in left ventricular end systolic volume index (-0.47 mL/m2; 95% CI, -1.18 to 0.23; P<0.01) compared with those in the lowest quartile. Individuals in the highest quartile had more severe risk factor adjusted global, mid, and apical regional dyssynchrony compared with those in the lowest, second, and third quartiles (all P-trend<0.05). Compared with the lowest-quartile group, the adjusted odds ratios for having myocardial scar was 1.3 (95% CI, 0.7-2.2) for quartile 2; 1.2 (95% CI, 0.6-2.3) for quartile 3; and 2.7 (95% CI, 1.4-5.5) for quartile 4 (P-trend=0.012) for the total sample. Conclusions Among participants without baseline clinical cardiovascular disease, higher baseline NT-proBNP concentration was significantly associated with subclinical changes in developing myocardial dysfunction, more severe cardiac dyssynchrony, and higher odds of having myocardial scar over a 10-year period independent of traditional cardiovascular disease risk factors.

2.
J Hum Genet ; 65(10): 875-887, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32483274

RESUMO

New Guineans represent one of the oldest locally continuous populations outside Africa, harboring among the greatest linguistic and genetic diversity on the planet. Archeological and genetic evidence suggest that their ancestors reached Sahul (present day New Guinea and Australia) by at least 55,000 years ago (kya). However, little is known about this early settlement phase or subsequent dispersal and population structuring over the subsequent period of time. Here we report 379 complete Papuan mitochondrial genomes from across Papua New Guinea, which allow us to reconstruct the phylogenetic and phylogeographic history of northern Sahul. Our results support the arrival of two groups of settlers in Sahul within the same broad time window (50-65 kya), each carrying a different set of maternal lineages and settling Northern and Southern Sahul separately. Strong geographic structure in northern Sahul remains visible today, indicating limited dispersal over time despite major climatic, cultural, and historical changes. However, following a period of isolation lasting nearly 20 ky after initial settlement, environmental changes postdating the Last Glacial Maximum stimulated diversification of mtDNA lineages and greater interactions within and beyond Northern Sahul, to Southern Sahul, Wallacea and beyond. Later, in the Holocene, populations from New Guinea, in contrast to those of Australia, participated in early interactions with incoming Asian populations from Island Southeast Asia and continuing into Oceania.

3.
Hum Genet ; 139(1): 45-59, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31630246

RESUMO

Due to its long genetic evolutionary history, Africans exhibit more genetic variation than any other population in the world. Their genetic diversity further lends itself to subdivisions of Africans into groups of individuals with a genetic similarity of varying degrees of granularity. It remains challenging to detect fine-scale structure in a computationally efficient and meaningful way. In this paper, we present a proof-of-concept of a novel fine-scale population structure detection tool with Western African samples. These samples consist of 1396 individuals from 25 ethnic groups (two groups are African American descendants). The strategy is based on a recently developed tool called IPCAPS. IPCAPS, or Iterative Pruning to CApture Population Structure, is a genetic divisive clustering strategy that enhances iterative pruning PCA, is robust to outliers and does not require a priori computation of haplotypes. Our strategy identified in total 12 groups and 6 groups were revealed as fine-scale structure detected in the samples from Cameroon, Gambia, Mali, Southwest USA, and Barbados. Our finding helped to explain evolutionary processes in the analyzed West African samples and raise awareness for fine-scale structure resolution when conducting genome-wide association and interaction studies.


Assuntos
Grupo com Ancestrais do Continente Africano/genética , Grupos Étnicos/genética , Variação Genética , Genética Populacional , Estudo de Associação Genômica Ampla , Haplótipos , Software , África Ocidental/etnologia , Humanos
4.
Zootaxa ; 4695(4): zootaxa.4695.4.5, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31719343

RESUMO

The article deals with the report of 5 suctorians viz. Lecanophryella satyanandani (Santhakumari, 1986), Paracineta karunakarani Santhakumari, 1986, Ephelota gemmipara (Hertwig, 1876), Acineta foetida Maupas, 1881 and Pelagacineta sp. on marine pelagic ostracods Cypridina dentata (Müller, 1906) from new localities of the Arabian Sea. Diagnostic characters of Paracineta karunakarani are emended. Ephelota gemmipara (Hertwig, 1876) and Acineta foetida Maupas, 1881 are reported here for the first time on planktonic marine ostracods. Pelagacineta sp. is reported for the first time as epibiont on ostracods and from the Indian Ocean.


Assuntos
Cilióforos , Crustáceos , Animais , Oceano Índico , Plâncton
5.
Environ Monit Assess ; 191(7): 420, 2019 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-31177343

RESUMO

In a study carried out during 2014, bacteria associated with zooplankton in the Zuari estuary were three to four orders of magnitude higher in abundance than in seawater. The live zooplankton carried much more bacterial load compared with the carcasses, and the fecal pellets harbored the highest density of bacteria, i.e., 8 × 1013 CFU cm-3. The diversity of bacteria was higher in live zooplankton and also in seawater. But the activity of the zooplankton-associated bacteria was much higher compared with the free-living ones. Most of the associated bacteria belonged to the genus Enterobacter, Pseudomonas, Aeromonas, and Bacillus. In growth experiments, Aeromonas and Bacillus were found to have lower salinity optima than Enterobacter (20 psu) and Vibrio and Pseudomonas (normal seawater salinity). Better growth of bacteria was observed in the medium containing the diatom Chaetoceros sp. than Navicula sp. Bacterial isolates were also able to survive in oligotrophic conditions and produce optimum biomass in 2 days at salinity 5 psu, but in freshwater, the bacteria took a week's time to attain the optima. At salinities 0-35, the bacteria survived even for 3 months without nutrient addition, indicating resilience in these bacteria and mechanisms to persist in the estuaries even in adverse conditions.


Assuntos
Bactérias/isolamento & purificação , Monitoramento Ambiental/métodos , Estuários , Água do Mar/microbiologia , Zooplâncton/microbiologia , Animais , Biomassa , Diatomáceas/microbiologia , Fezes/microbiologia , Água Doce/microbiologia , Índia , Salinidade , Estações do Ano
6.
Genome Biol Evol ; 11(3): 748-758, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30715341

RESUMO

The Austronesian dispersal across the Indonesian Ocean to Madagascar and the Comoros has been well documented, but in an unexplained anomaly, few to no traces have been found of the Austronesian expansion in East Africa or the Arabian Peninsula. To revisit this peculiarity, we surveyed the Western Indian Ocean rim populations to identify potential Austronesian genetic ancestry. We generated full mitochondrial DNA genomes and genome-wide genotyping data for these individuals and compared them with the Banjar, the Indonesian source population of the westward Austronesian dispersal. We find strong support for Asian genetic contributions to maternal lineages and autosomal variation in modern day Somalia and Yemen. Surprisingly, this input reveals two apparently different geographic origins and timings of admixture for the Austronesian contact; one at a very early phase (likely associated with the early Austronesian dispersals), and a later movement dating to the end of nineteenth century. These Austronesian gene flows come, respectively, from Madagascar and directly from an unidentified location in Island Southeast Asia. This result reveals a far more complex dynamic of Austronesian dispersals through the Western Indian Ocean than has previously been understood and suggests that Austronesian movements within the Indian Ocean may have been part of a lengthy process, probably continuing well into the modern era.


Assuntos
Fluxo Gênico , Genoma Mitocondrial , Migração Humana , África Oriental , Arábia , Bornéu , Humanos , Ilhas do Oceano Índico
7.
Mol Biol Evol ; 36(3): 575-586, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30649405

RESUMO

The Arabian Peninsula (AP) was an important crossroad between Africa, Asia, and Europe, being the cradle of the structure defining these main human population groups, and a continuing path for their admixture. The screening of 741,000 variants in 420 Arabians and 80 Iranians allowed us to quantify the dominant sub-Saharan African admixture in the west of the peninsula, whereas South Asian and Levantine/European influence was stronger in the east, leading to a rift between western and eastern sides of the Peninsula. Dating of the admixture events indicated that Indian Ocean slave trade and Islamization periods were important moments in the genetic makeup of the region. The western-eastern axis was also observable in terms of positive selection of diversity conferring lactose tolerance, with the West AP developing local adaptation and the East AP acquiring the derived allele selected in European populations and existing in South Asia. African selected malaria resistance through the DARC gene was enriched in all Arabian genomes, especially in the western part. Clear European influences associated with skin and eye color were equally frequent across the Peninsula.


Assuntos
Árabes/genética , Fluxo Gênico , Genoma Humano , Humanos , Oriente Médio , Filogeografia
8.
Mitochondrion ; 46: 123-133, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-29631022

RESUMO

We conducted the first systematic omics study of the oncocytic phenotype in 488 papillary thyroid carcinomas (PTC) from The Cancer Genome Atlas. Oncocytic phenotype is secondary to PTC, being unrelated to several pathologic scores. The nuclear genome had low impact on this phenotype (except in specific copy number variation), which was mostly driven by the significant accumulation of mitochondrial DNA non-synonymous and frameshift mutations at high heteroplasmy levels. Energy and mitochondrial-related pathways were significantly enriched in oncocytic tumors that also displayed increased levels of expression for genes involved in autophagy and fusion of mitochondria. Our in vitro tests confirmed that autophagy is increased and functional while mitophagy is decreased in these tumors.


Assuntos
DNA Mitocondrial/genética , Perfilação da Expressão Gênica , Mutação , Células Oxífilas/patologia , Neoplasias da Glândula Tireoide/patologia , Autofagia , Metabolismo Energético/genética , Humanos , Mitofagia , Células Oxífilas/fisiologia
9.
Exp Mol Pathol ; 105(3): 279-284, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30291855

RESUMO

The physiopathology of autoimmune hepatitis (AIH) is complex and still not fully elucidated. The genes localized outside the histocompatibility complex involved in regulation and signal transduction of the immune system SH2B3, TGFß1, STAT4 and PTPN22 could be associated to the susceptibility and hepatocyte lysis mechanism of this lethal autoimmune disorder. PATIENTS AND METHODS: We investigated four polymorphic sites in SH2B3 (rs3184504), TGFß1 (rs1800471), STAT4 (rs7574865) and PTPN22 (rs2476601) in 45 AIH patients and 150 healthy controls from Tunisia using real-time PCR. RESULTS: Significant associations were found for SH2B3 T allele (OR = 1.861; p = 0.015, pc = 0.366) and PTPN22 A allele (OR = 7.070; p = 0.026; pc = 1.00) and AIH with opposite homozygous being protective against the disease (CC genotype with OR = 0.420, p = 0.025; GG genotype with OR = 0.136, p = 0.025, respectively). No statistically significant associations were found for the TGFß1 and STAT4 polymorphisms with AIH susceptibility. CONCLUSION: Our work enlarges information on non-HLA genes that are associated with AIH by focusing in a region of the world that was poorly molecularly characterized for this disease.


Assuntos
Hepatite Autoimune/genética , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Proteínas/genética , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT4/genética , Fator de Crescimento Transformador beta1/genética , Tunísia
10.
Infect Genet Evol ; 62: 60-72, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29673983

RESUMO

Population genetics theory predicted that rare frequent markers would be the main contributors for heritability of complex diseases, but meta-analyses of genome-wide association studies are revealing otherwise common markers, present in all population groups, as the identified candidate genes. In this work, we applied a population-genetics informed meta-analysis to 10 markers located in seven genes said to be associated with dengue fever disease. Seven markers (in PLCE1, CD32, CD209, OAS1 and OAS3 genes) have high-frequency and the other three (in MICB and TNFA genes) have intermediate frequency. Most of these markers have high discriminatory power between population groups, but their frequencies follow the rules of genetic drift, and seem to have not been under strong selective pressure. There was a good agreement in directional consistency across trans-ethnic association signals, in East Asian and Latin American cohorts, with heterogeneity generated by randomness between studies and especially by low sample sizes. This led to confirm the following significant associations: with DF, odds ratio of 0.67 for TNFA-rs1800629-A; with DHF, 0.82 for CD32-rs1801274-G; with DSS, 0.55 for OAS3-rs2285933-G, 0.80 for PLCE1-rs2274223-G and 1.32 for MICB-rs3132468-C. The overall genetic risks confirmed sub-Saharan African populations and descendants as the best protected against the severer forms of the disease, while Southeast and Northeast Asians are the least protected ones. European and close neighbours are the best protected against dengue fever, while, again, Southeast and Northeast Asians are the least protected ones. These risk scores provide important predictive information for the largely naïve European and North American regions, as well as for Africa where misdiagnosis with other hemorrhagic diseases is of concern.


Assuntos
Dengue/genética , Predisposição Genética para Doença , Regulação da Expressão Gênica , Marcadores Genéticos , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único
11.
PLoS Negl Trop Dis ; 12(2): e0006202, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29447178

RESUMO

Ethnic diversity has been long considered as one of the factors explaining why the severe forms of dengue are more prevalent in Southeast Asia than anywhere else. Here we take advantage of the admixed profile of Southeast Asians to perform coupled association-admixture analyses in Thai cohorts. For dengue shock syndrome (DSS), the significant haplotypes are located in genes coding for phospholipase C members (PLCB4 added to previously reported PLCE1), related to inflammation of blood vessels. For dengue fever (DF), we found evidence of significant association with CHST10, AHRR, PPP2R5E and GRIP1 genes, which participate in the xenobiotic metabolism signaling pathway. We conducted functional analyses for PPP2R5E, revealing by immunofluorescence imaging that the coded protein co-localizes with both DENV1 and DENV2 NS5 proteins. Interestingly, only DENV2-NS5 migrated to the nucleus, and a deletion of the predicted top-linking motif in NS5 abolished the nuclear transfer. These observations support the existence of differences between serotypes in their cellular dynamics, which may contribute to differential infection outcome risk. The contribution of the identified genes to the genetic risk render Southeast and Northeast Asian populations more susceptible to both phenotypes, while African populations are best protected against DSS and intermediately protected against DF, and Europeans the best protected against DF but the most susceptible against DSS.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Vírus da Dengue/genética , Dengue/genética , Genoma Viral/genética , Estudo de Associação Genômica Ampla , Dengue Grave/genética , Adolescente , Adulto , Ásia Sudeste , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas de Transporte/genética , Linhagem Celular , Núcleo Celular/virologia , Pré-Escolar , Estudos de Coortes , Dengue/virologia , Feminino , Expressão Gênica , Predisposição Genética para Doença , Genótipo , Humanos , Lactente , Masculino , Proteínas do Tecido Nervoso/genética , Razão de Chances , Proteína Fosfatase 2/genética , Proteínas Repressoras/genética , Sorogrupo , Dengue Grave/etnologia , Sulfotransferases , Tailândia , Fosfolipases Tipo C/genética , Proteínas não Estruturais Virais/genética , Proteínas Virais/genética , Adulto Jovem
12.
Am J Hum Genet ; 102(1): 58-68, 2018 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-29304377

RESUMO

At the dawn of the second millennium, the expansion of the Indian Ocean trading network aligned with the emergence of an outward-oriented community along the East African coast to create a cosmopolitan cultural and trading zone known as the Swahili Corridor. On the basis of analyses of new genome-wide genotyping data and uniparental data in 276 individuals from coastal Kenya and the Comoros islands, along with large-scale genetic datasets from the Indian Ocean rim, we reconstruct historical population dynamics to show that the Swahili Corridor is largely an eastern Bantu genetic continuum. Limited gene flows from the Middle East can be seen in Swahili and Comorian populations at dates corresponding to historically documented contacts. However, the main admixture event in southern insular populations, particularly Comorian and Malagasy groups, occurred with individuals from Island Southeast Asia as early as the 8th century, reflecting an earlier dispersal from this region. Remarkably, our results support recent archaeological and linguistic evidence-based suggestions that the Comoros archipelago was the earliest location of contact between Austronesian and African populations in the Swahili Corridor.


Assuntos
Fluxo Gênico , Genética Populacional , Ásia , Austrália , Comores , Variação Genética , Humanos , Quênia , Polimorfismo de Nucleotídeo Único/genética
13.
Am J Phys Anthropol ; 164(2): 424-434, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28736914

RESUMO

BACKGROUND: Today, African pastoralists are found mainly in the Sahel/Savannah belt spanning 6,000 km from west to east, flanked by the Sahara to the north and tropical rainforests to the south. The most significant group among them are the Fulani who not only keep cattle breeds of possible West Eurasian ancestry, but form themselves a gene pool containing some paternally and maternally-transmitted West Eurasian haplogroups. MATERIALS AND METHODS: We generated complete sequences for 33 mitogenomes belonging to haplogroups H1 and U5 (23 and 10, respectively), and genotyped 16 STRs in 65 Y chromosomes belonging to haplogroup R1b-V88. RESULTS: We show that age estimates of the maternal lineage H1cb1, occurring almost exclusively in the Fulani, point to the time when the first cattle herders settled the Sahel/Savannah belt. Similar age estimates were obtained for paternal lineage R1b-V88, which occurs today in the Fulani but also in other, mostly pastoral populations. Maternal clade U5b1b1b, reported earlier in the Berbers, shows a shallower age, suggesting another possibly independent input into the Sahelian pastoralist gene pool. CONCLUSIONS: Despite the fact that animal domestication originated in the Near East ∼ 10 ka, and that it was from there that animals such as sheep, goats as well as cattle were introduced into Northeast Africa soon thereafter, contemporary cattle keepers in the Sahel/Savannah belt show uniparental genetic affinities that suggest the possibility of an ancient contact with an additional ancestral population of western Mediterranean ancestry.


Assuntos
Grupo com Ancestrais do Continente Africano/genética , Agricultura/história , DNA Mitocondrial/genética , Haplótipos/genética , Migração Humana/história , África ao Sul do Saara , Antropologia Física , Cromossomos Humanos Y/genética , Genética Populacional , História Antiga , Humanos , Masculino , Filogenia
14.
Science ; 356(6337): 543-546, 2017 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-28473590

RESUMO

Bantu languages are spoken by about 310 million Africans, yet the genetic history of Bantu-speaking populations remains largely unexplored. We generated genomic data for 1318 individuals from 35 populations in western central Africa, where Bantu languages originated. We found that early Bantu speakers first moved southward, through the equatorial rainforest, before spreading toward eastern and southern Africa. We also found that genetic adaptation of Bantu speakers was facilitated by admixture with local populations, particularly for the HLA and LCT loci. Finally, we identified a major contribution of western central African Bantu speakers to the ancestry of African Americans, whose genomes present no strong signals of natural selection. Together, these results highlight the contribution of Bantu-speaking peoples to the complex genetic history of Africans and African Americans.


Assuntos
Adaptação Fisiológica/genética , Afro-Americanos/genética , Loci Gênicos , Antígenos HLA/genética , Lactase/genética , Idioma , África Central , Migração Humana , Humanos , América do Norte , Polimorfismo de Nucleotídeo Único , Floresta Úmida , Fala
15.
Sci Rep ; 7: 46044, 2017 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-28387361

RESUMO

Human mitochondrial DNA haplogroup U is among the initial maternal founders in Southwest Asia and Europe and one that best indicates matrilineal genetic continuity between late Pleistocene hunter-gatherer groups and present-day populations of Europe. While most haplogroup U subclades are older than 30 thousand years, the comparatively recent coalescence time of the extant variation of haplogroup U7 (~16-19 thousand years ago) suggests that its current distribution is the consequence of more recent dispersal events, despite its wide geographical range across Europe, the Near East and South Asia. Here we report 267 new U7 mitogenomes that - analysed alongside 100 published ones - enable us to discern at least two distinct temporal phases of dispersal, both of which most likely emanated from the Near East. The earlier one began prior to the Holocene (~11.5 thousand years ago) towards South Asia, while the later dispersal took place more recently towards Mediterranean Europe during the Neolithic (~8 thousand years ago). These findings imply that the carriers of haplogroup U7 spread to South Asia and Europe before the suggested Bronze Age expansion of Indo-European languages from the Pontic-Caspian Steppe region.


Assuntos
DNA Mitocondrial/genética , Evolução Molecular , Haplótipos/genética , Teorema de Bayes , Geografia , Humanos , Mutação/genética , Filogenia
16.
J Cardiovasc Magn Reson ; 18(1): 39, 2016 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-27306901

RESUMO

BACKGROUND: Prognosis in pulmonary hypertension (PH) is related to right ventricular (RV) function. Quantification of RV mechanics may offer additive value. The objective of our study is to determine the feasibility and clinical and prognostic value of RV strain analysis by cardiovascular magnetic resonance (CMR) based feature tracking (FT) in PH. METHODS: We retrospectively enrolled 116 patients (age 52.2 ± 12 years, 73.6 % women) referred to CMR for PH evaluation who underwent right heart catheterization within 1 month. Using dedicated FT software, peak global longitudinal and circumferential RV strain and strain rates (GLS, GCS, GLSR, and GCSR, respectively) were quantified from standard cine images. Using multivariate regression analysis, we evaluated the associations of strain with a composite endpoint of death, lung transplantation, or functional class deterioration. RESULTS: RV strain analysis was feasible in 110 (95 %) patients. Patients were classified into: Group A (no PH, normal right ventricular ejection fraction [RVEF]; n = 17), Group B (PH, normal RVEF; n = 26), or Group C (PH, abnormal RVEF; n = 67). All strain and strain rate values were reduced in Group C. Furthermore, GCSR was significantly reduced in Group B (-0.92 [-1.0/-0.7]; p < 0.001) compared to Group A (-1.12 [-1.3/-0.9]; p < 0.001). After adjustment for six clinically meaningful covariates, GLS (hazard ratio 1.06; p = 0.026), GLSR (hazard ratio 2.52; p = 0.04), and GCSR (hazard ratio 4.5; p = 0.01) were independently associated with the composite endpoint. GCSR successfully discriminated patients with and without events (p = 0.01). CONCLUSIONS: Quantification of RV strain with CMR-FT is feasible in the majority of patients, correlates with disease severity, and is independently associated with poor outcomes in PH.


Assuntos
Hipertensão Pulmonar/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Disfunção Ventricular Direita/diagnóstico por imagem , Função Ventricular Direita , Adulto , Fenômenos Biomecânicos , Distribuição de Qui-Quadrado , Progressão da Doença , Estudos de Viabilidade , Feminino , Humanos , Hipertensão Pulmonar/mortalidade , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/cirurgia , Interpretação de Imagem Assistida por Computador , Estimativa de Kaplan-Meier , Transplante de Pulmão , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Contração Miocárdica , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Estresse Mecânico , Volume Sistólico , Fatores de Tempo , Disfunção Ventricular Direita/mortalidade , Disfunção Ventricular Direita/fisiopatologia
17.
Psicol. educ ; (41): 37-49, dic. 2015. ilus, tab
Artigo em Português | LILACS-Express | LILACS | ID: lil-782717

RESUMO

Este artigo tem como objetivo analisar se as estratégias de aprendizagem autorregulatórias desenvolvidas em uma prática de ensino reflexiva contribuíram para a formação de alunos autorregulados e possibilitaram a promoção de avanços na aprendizagem de alunos do ensino superior relativas à escrita de um artigo científico. A prática de ensino reflexiva desenvolveu-se durante seis encontros nos quais buscou-se perceber a tomada de consciência, o controle e a gestão do aluno em seu processo de aprendizagem. Iniciou-se a pesquisa com a aplicação do questionário CEA (Conhecimento de Estratégias Autorregulatórias), seguido das "Oficinas de desenvolvimento de estratégias autorregulatórias da aprendizagem" as quais tiveram como objetivo principal, para os sujeitos pesquisados, aprender estratégias para a escrita de artigos científicos e, para a pesquisadora, analisar se as estratégias utilizadas nessa prática reflexiva promoveriam a autorregulação para a escrita de artigos científicos. Ao final dos encontros, após seis meses da intervenção, aplicou-se novamente o questionário CEA em uma entrevista semiestruturada. Da análise dos dados, emergiram duas categorias: 1) Estratégias Cognitivas e Metacognitivas; 2) Estratégias Motivacionais; que articuladas entre si contribuem significativamente para a formação de um aluno autorregulado. Conclui-se que os dados reforçam a importância do conhecimento de estratégias autorregulatórias nos processos de aprendizagem, a fim de que o aluno universitário seja capaz de atingir seus objetivos diante das tarefas, promovendo uma consciência reflexiva.


This article aims to examine whether self-regulatory learning strategies developed in a practice of reflective teaching contributed to the formation of self-regulated learners and enabled the promotion of advances in the learning of a group of students in higher education to support them in a scientific article production. The practice of reflective teaching, developed during six meetings, found if the student showed awareness, control and management of their learning process. We started the research with the questionnaire CEA (Knowledge of self-regulatory strategies), followed by six "Workshops for development of self-regulatory learning strategies". These meetings mainly aimed for those individuals surveyed, learn strategies for writing papers and for the researcher to analyze the strategies used in this reflective practice in higher education, would promote self-regulation by stimulating the processes students learn college. At the end of the meetings, 6 months after the intervention was applied CEA questionnaire and a semi-structured interview. From the data analysis, two categories emerged: 1) Cognitive and Metacognitive Strategies; 2) Motivational Strategies; that articulated between them indicate that contributed significantly to the formation of the self-regulated learner. We conclude that the data support the importance of the knowledge of self-regulatory strategies in the learning process, so that the university student is able to achieve their goals in tasks, promoting a reflective consciousness.


Este artículo tiene como objetivo analizar si las estrategias de aprendizaje, de autorregulación desarrolladas en la práctica de la enseñanza reflexiva, contribuyeron a formación de estudiantes autorregulados y permitieron la promoción de los avances en la aprendizaje de un grupo de estudiantes de educación superior para la producción de un artículo científico. La práctica de la enseñanza reflexiva se desarrolló durante seis reuniones: pesquisó, a partir de las estrategias de aprendizaje de autorregulación, si estudiante mostro conciencia, control y gestión de su proceso de aprendizaje. Comenzó la investigación con la aplicación del cuestionario CEA (Conocimiento de Estrategias de Autorregulación), seguido de seis "Talleres de desarrollo de estrategias de autorregulación de la aprendizaje" como objetivo principal, para los sujetos, aprender estrategias para escribir artículos científicos y, para el investigador , analizar si las estrategias utilizadas en esta práctica reflexiva, promueven la autorregulación mediante la estimulación de los procesos de aprendizaje de los estudiantes de la universidad. Seis meses después de la intervención, se aplicó de nuevo cuestionario CEA y una entrevista semi-estructurada. Del análisis de datos, emergieron categorías: 1) Estrategias cognitivas y metacognitivas; 2) Estrategias de motivación. Os datos apoyan la importancia del conocimiento de las estrategias de autorregulación en el proceso de aprendizaje, por lo que el estudiante universitario es capaz de alcanzar sus objetivos en las tareas, con promoción de una conciencia reflexiva.

18.
Genome Biol Evol ; 7(12): 3484-95, 2015 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-26614524

RESUMO

Genome-wide studies of African populations have the potential to reveal powerful insights into the evolution of our species, as these diverse populations have been exposed to intense selective pressures imposed by infectious diseases, diet, and environmental factors. Within Africa, the Sahel Belt extensively overlaps the geographical center of several endemic infections such as malaria, trypanosomiasis, meningitis, and hemorrhagic fevers. We screened 2.5 million single nucleotide polymorphisms in 161 individuals from 13 Sahelian populations, which together with published data cover Western, Central, and Eastern Sahel, and include both nomadic and sedentary groups. We confirmed the role of this Belt as a main corridor for human migrations across the continent. Strong admixture was observed in both Central and Eastern Sahelian populations, with North Africans and Near Eastern/Arabians, respectively, but it was inexistent in Western Sahelian populations. Genome-wide local ancestry inference in admixed Sahelian populations revealed several candidate regions that were significantly enriched for non-autochthonous haplotypes, and many showed to be under positive selection. The DARC gene region in Arabs and Nubians was enriched for African ancestry, whereas the RAB3GAP1/LCT/MCM6 region in Oromo, the TAS2R gene family in Fulani, and the ALMS1/NAT8 in Turkana and Samburu were enriched for non-African ancestry. Signals of positive selection varied in terms of geographic amplitude. Some genomic regions were selected across the Belt, the most striking example being the malaria-related DARC gene. Others were Western-specific (oxytocin, calcium, and heart pathways), Eastern-specific (lipid pathways), or even population-restricted (TAS2R genes in Fulani, which may reflect sexual selection).


Assuntos
Genoma Humano , Migração Humana , Seleção Genética , Acetiltransferases/genética , África , Proteínas de Ciclo Celular , Sistema do Grupo Sanguíneo Duffy/genética , Haplótipos , Febres Hemorrágicas Virais/genética , Humanos , Malária/genética , Meningite/genética , Componente 6 do Complexo de Manutenção de Minicromossomo/genética , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Receptores de Superfície Celular/genética , Receptores Acoplados a Proteínas-G/genética
19.
Hum Mutat ; 36(11): 1100-11, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26252938

RESUMO

A high-resolution mtDNA phylogenetic tree allowed us to look backward in time to investigate purifying selection. Purifying selection was very strong in the last 2,500 years, continuously eliminating pathogenic mutations back until the end of the Younger Dryas (∼11,000 years ago), when a large population expansion likely relaxed selection pressure. This was preceded by a phase of stable selection until another relaxation occurred in the out-of-Africa migration. Demography and selection are closely related: expansions led to relaxation of selection and higher pathogenicity mutations significantly decreased the growth of descendants. The only detectible positive selection was the recurrence of highly pathogenic nonsynonymous mutations (m.3394T>C-m.3397A>G-m.3398T>C) at interior branches of the tree, preventing the formation of a dinucleotide STR (TATATA) in the MT-ND1 gene. At the most recent time scale in 124 mother-children transmissions, purifying selection was detectable through the loss of mtDNA variants with high predicted pathogenicity. A few haplogroup-defining sites were also heteroplasmic, agreeing with a significant propensity in 349 positions in the phylogenetic tree to revert back to the ancestral variant. This nonrandom mutation property explains the observation of heteroplasmic mutations at some haplogroup-defining sites in sequencing datasets, which may not indicate poor quality as has been claimed.


Assuntos
DNA Mitocondrial , Genética Populacional , Mutação , Seleção Genética , Alelos , Biologia Computacional/métodos , Evolução Molecular , Família , Feminino , Humanos , Masculino , Filogenia
20.
PLoS One ; 10(3): e0118625, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25738654

RESUMO

At the crossroads between Africa and Eurasia, Arabia is necessarily a melting pot, its peoples enriched by successive gene flow over the generations. Estimating the timing and impact of these multiple migrations are important steps in reconstructing the key demographic events in the human history. However, current methods based on genome-wide information identify admixture events inefficiently, tending to estimate only the more recent ages, as here in the case of admixture events across the Red Sea (~8-37 generations for African input into Arabia, and 30-90 generations for "back-to-Africa" migrations). An mtDNA-based founder analysis, corroborated by detailed analysis of the whole-mtDNA genome, affords an alternative means by which to identify, date and quantify multiple migration events at greater time depths, across the full range of modern human history, albeit for the maternal line of descent only. In Arabia, this approach enables us to infer several major pulses of dispersal between the Near East and Arabia, most likely via the Gulf corridor. Although some relict lineages survive in Arabia from the time of the out-of-Africa dispersal, 60 ka, the major episodes in the peopling of the Peninsula took place from north to south in the Late Glacial and, to a lesser extent, the immediate post-glacial/Neolithic. Exchanges across the Red Sea were mainly due to the Arab slave trade and maritime dominance (from ~2.5 ka to very recent times), but had already begun by the early Holocene, fuelled by the establishment of maritime networks since ~8 ka. The main "back-to-Africa" migrations, again undetected by genome-wide dating analyses, occurred in the Late Glacial period for introductions into eastern Africa, whilst the Neolithic was more significant for migrations towards North Africa.


Assuntos
DNA Mitocondrial/genética , Demografia/história , Fluxo Gênico , Migração Humana/história , África , Arábia , Efeito Fundador , Genômica , Haplótipos , História Antiga , Humanos , Filogenia , Análise de Componente Principal
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