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  1 / 1882 MEDLINE  
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[PMID]:29458554
[Au] Autor:Osaka S; Okuzumi K; Koide S; Tamai K; Sato T; Tanimoto K; Tomita H; Suzuki M; Nagano Y; Shibayama K; Arakawa Y; Nagano N
[Ad] Endereço:1​Department of Health and Medical Sciences, Shinshu University Graduate School of Medicine, Nagano, Japan.
[Ti] Título:Genetic shifts in methicillin-resistant Staphylococcus aureus epidemic clones and toxin gene profiles in Japan: comparative analysis among pre-epidemic, epidemic and post-epidemic phases.
[So] Source:J Med Microbiol;67(3):392-399, 2018 Mar.
[Is] ISSN:1473-5644
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:PURPOSE: The decline in methicillin-resistant Staphylococcus aureus (MRSA) isolation rates has become a general observation worldwide, including Japan. We hypothesized that some genetic shift in MRSA might cause this phenomenon, and therefore we investigated the genetic profiles among MRSA clinical isolates obtained from three different epidemic phases in Japan. METHODOLOGY: A total of 353 MRSA isolates were selected from 202 medical facilities in 1990 (pre-epidemic phase), 2004 (epidemic phase) and 2016 (post-epidemic phase). Molecular typing was performed by PCR detection of 22 genes using the polymerase chain reaction (PCR)-based ORF typing (POT) system, including an additional eight genes including small genomic islets and seven toxin genes. RESULTS: Isolates with a POT1 of score 93, identified as presumed clonal complex (pCC)5-staphylococcal cassette chromosome mec (SCCmec) type II including ST5-SCCmec type II New York/Japan clone, represented the major epidemic MRSA lineage in 1990 and 2004. In 2016, however, a marked decrease in isolates with a POT1 score of 93, along with changes in the epidemiology of toxin genes carried, was noted, where the carriers of tst genes including the tst-sec combination were markedly reduced, and those possessing the seb gene alone were markedly increased. Rather, isolates with a POT1 score of 106, including pCC1 or pCC8 among the isolates with SCCmec type IV, which often links to community-associated MRSA, were predominant. Interestingly, the pCC1 and pCC8 lineages were related to sea and tst-sec carriage, respectively. CONCLUSIONS: Over time, a transition in MRSA genetic profiles from a POT1 score of 93 in 1990 and 2004 to 106 in 2014 was found in Japan.
[Mh] Termos MeSH primário: Toxinas Bacterianas/genética
Epidemias
Deriva Genética
Staphylococcus aureus Resistente à Meticilina/genética
Infecções Estafilocócicas/epidemiologia
Infecções Estafilocócicas/microbiologia
[Mh] Termos MeSH secundário: Antibacterianos/farmacologia
Infecção Hospitalar/epidemiologia
Exotoxinas/genética
Seres Humanos
Japão/epidemiologia
Leucocidinas/genética
Meticilina/farmacologia
Resistência a Meticilina/genética
Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos
Staphylococcus aureus Resistente à Meticilina/isolamento & purificação
Testes de Sensibilidade Microbiana
Tipagem Molecular
Fatores de Virulência/genética
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Bacterial Toxins); 0 (Exotoxins); 0 (Leukocidins); 0 (Virulence Factors); Q91FH1328A (Methicillin)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180221
[St] Status:MEDLINE
[do] DOI:10.1099/jmm.0.000687


  2 / 1882 MEDLINE  
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[PMID]:28746770
[Au] Autor:Schou MF; Loeschcke V; Bechsgaard J; Schlötterer C; Kristensen TN
[Ad] Endereço:Department of Bioscience, Aarhus University, Aarhus C, Denmark.
[Ti] Título:Unexpected high genetic diversity in small populations suggests maintenance by associative overdominance.
[So] Source:Mol Ecol;26(23):6510-6523, 2017 Dec.
[Is] ISSN:1365-294X
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The effective population size (N ) is a central factor in determining maintenance of genetic variation. The neutral theory predicts that loss of variation depends on N , with less genetic drift in larger populations. We monitored genetic drift in 42 Drosophila melanogaster populations of different adult census population sizes (10, 50 or 500) using pooled RAD sequencing. In small populations, variation was lost at a substantially lower rate than expected. This observation was consistent across two ecological relevant thermal regimes, one stable and one with a stressful increase in temperature across generations. Estimated ratios between N and adult census size were consistently higher in small than in larger populations. The finding provides evidence for a slower than expected loss of genetic diversity and consequently a higher than expected long-term evolutionary potential in small fragmented populations. More genetic diversity was retained in areas of low recombination, suggesting that associative overdominance, driven by disfavoured homozygosity of recessive deleterious alleles, is responsible for the maintenance of genetic diversity in smaller populations. Consistent with this hypothesis, the X-chromosome, which is largely free of recessive deleterious alleles due to hemizygosity in males, fits neutral expectations even in small populations. Our experiments provide experimental answers to a range of unexpected patterns in natural populations, ranging from variable diversity on X-chromosomes and autosomes to surprisingly high levels of nucleotide diversity in small populations.
[Mh] Termos MeSH primário: Drosophila melanogaster/genética
Variação Genética
Genética Populacional
[Mh] Termos MeSH secundário: Animais
Evolução Molecular
Feminino
Deriva Genética
Aptidão Genética
Masculino
Modelos Genéticos
Densidade Demográfica
Temperatura Ambiente
Cromossomo X/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180215
[Lr] Data última revisão:
180215
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170727
[St] Status:MEDLINE
[do] DOI:10.1111/mec.14262


  3 / 1882 MEDLINE  
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[PMID]:29194439
[Au] Autor:Weinstein BT; Lavrentovich MO; Möbius W; Murray AW; Nelson DR
[Ad] Endereço:School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts, United States of America.
[Ti] Título:Genetic drift and selection in many-allele range expansions.
[So] Source:PLoS Comput Biol;13(12):e1005866, 2017 Dec.
[Is] ISSN:1553-7358
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:We experimentally and numerically investigate the evolutionary dynamics of four competing strains of E. coli with differing expansion velocities in radially expanding colonies. We compare experimental measurements of the average fraction, correlation functions between strains, and the relative rates of genetic domain wall annihilations and coalescences to simulations modeling the population as a one-dimensional ring of annihilating and coalescing random walkers with deterministic biases due to selection. The simulations reveal that the evolutionary dynamics can be collapsed onto master curves governed by three essential parameters: (1) an expansion length beyond which selection dominates over genetic drift; (2) a characteristic angular correlation describing the size of genetic domains; and (3) a dimensionless constant quantifying the interplay between a colony's curvature at the frontier and its selection length scale. We measure these parameters with a new technique that precisely measures small selective differences between spatially competing strains and show that our simulations accurately predict the dynamics without additional fitting. Our results suggest that the random walk model can act as a useful predictive tool for describing the evolutionary dynamics of range expansions composed of an arbitrary number of genotypes with different fitnesses.
[Mh] Termos MeSH primário: Alelos
Evolução Molecular
Deriva Genética
Modelos Genéticos
Seleção Genética/genética
[Mh] Termos MeSH secundário: Algoritmos
Biologia Computacional
Simulação por Computador
Escherichia coli/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171227
[Lr] Data última revisão:
171227
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171202
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pcbi.1005866


  4 / 1882 MEDLINE  
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[PMID]:28981524
[Au] Autor:Blagoev KB; Wilkerson J; Burotto M; Kim C; Espinal-Domínguez E; García-Alfonso P; Alimchandani M; Miettinen M; Blanco-Codesido M; Fojo T
[Ad] Endereço:Physics of Living Systems, National Science Foundation, Arlington, Virginia, United States of America.
[Ti] Título:Neutral evolution of drug resistant colorectal cancer cell populations is independent of their KRAS status.
[So] Source:PLoS One;12(10):e0175484, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Emergence of tumor resistance to an anti-cancer therapy directed against a putative target raises several questions including: (1) do mutations in the target/pathway confer resistance? (2) Are these mutations pre-existing? (3) What is the relative fitness of cells with/without the mutation? We addressed these questions in patients with metastatic colorectal cancer (mCRC). We conducted an exhaustive review of published data to establish a median doubling time for CRCs and stained a cohort of CRCs to document mitotic indices. We analyzed published data and our own data to calculate rates of growth (g) and regression (d, decay) of tumors in patients with CRC correlating these results with the detection of circulating MT-KRAS DNA. Additionally we estimated mathematically the caloric burden of such tumors using data on mitotic and apoptotic indices. We conclude outgrowth of cells harboring intrinsic or acquired MT-KRAS cannot explain resistance to anti-EGFR (epidermal growth factor receptor) antibodies. Rates of tumor growth with panitumumab are unaffected by presence/absence of MT-KRAS. While MT-KRAS cells may be resistant to anti-EGFR antibodies, WT-KRAS cells also rapidly bypass this blockade suggesting inherent resistance mechanisms are responsible and a neutral evolution model is most appropriate. Using the above clinical data on tumor doubling times and mitotic and apoptotic indices we estimated the caloric intake required to support tumor growth and suggest it may explain in part cancer-associated cachexia.
[Mh] Termos MeSH primário: Anticorpos Monoclonais/farmacologia
Antineoplásicos/farmacologia
Neoplasias Colorretais/patologia
Resistência a Medicamentos Antineoplásicos/genética
Proteínas Proto-Oncogênicas p21(ras)/genética
[Mh] Termos MeSH secundário: Anticorpos Monoclonais/uso terapêutico
Antineoplásicos/uso terapêutico
Neoplasias Colorretais/tratamento farmacológico
Neoplasias Colorretais/genética
Neoplasias Colorretais/metabolismo
Análise Mutacional de DNA
Evolução Molecular
Deriva Genética
Seres Humanos
Mutação
Proteínas Proto-Oncogênicas p21(ras)/metabolismo
Receptor do Fator de Crescimento Epidérmico/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Monoclonal); 0 (Antineoplastic Agents); 0 (KRAS protein, human); 6A901E312A (panitumumab); EC 2.7.10.1 (Receptor, Epidermal Growth Factor); EC 3.6.5.2 (Proto-Oncogene Proteins p21(ras))
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171022
[Lr] Data última revisão:
171022
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171006
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0175484


  5 / 1882 MEDLINE  
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[PMID]:28972992
[Au] Autor:Ben Abdelkrim A; Hattab T; Fakhfakh H; Belkadhi MS; Gorsane F
[Ad] Endereço:Laboratoire de Génétique Moléculaire, Immunologie et Biotechnologie. Faculté des Sciences de Tunis, Université Tunis El Manar, Tunis, Tunisie.
[Ti] Título:A landscape genetic analysis of important agricultural pest species in Tunisia: The whitefly Bemisia tabaci.
[So] Source:PLoS One;12(10):e0185724, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Combining landscape ecology and genetics provides an excellent framework to appreciate pest population dynamics and dispersal. The genetic architectures of many species are always shaped by environmental constraints. Because little is known about the ecological and genetic traits of Tunisian whitefly populations, the main objective of this work is to highlight patterns of biodiversity, genetic structure and migration routes of this pest. We used nuclear microsatellite loci to analyze B. tabaci populations collected from various agricultural areas across the country and we determine their biotype status. Molecular data were subsequently interpreted in an ecological context supplied from a species distribution model to infer habitat suitability and hereafter the potential connection paths between sampling localities. An analysis of landscape resistance to B. tabaci genetic flow was thus applied to take into account habitat suitability, genetic relatedness and functional connectivity of habitats within a varied landscape matrix. We shed light on the occurrence of three geographically delineated genetic groups with high levels of genetic differentiation within each of them. Potential migration corridors of this pest were then established providing significant advances toward the understanding of genetic features and the dynamic dispersal of this pest. This study supports the hypothesis of a long-distance dispersal of B. tabaci followed by infrequent long-term isolations. The Inference of population sources and colonization routes is critical for the design and implementation of accurate management strategies against this pest.
[Mh] Termos MeSH primário: Fluxo Gênico
Deriva Genética
Repetições de Microssatélites
[Mh] Termos MeSH secundário: Distribuição Animal
Animais
Testes Genéticos
Hemípteros/genética
Tunísia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171019
[Lr] Data última revisão:
171019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171004
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0185724


  6 / 1882 MEDLINE  
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[PMID]:28827410
[Au] Autor:Johnson DC; Lenive O; Mitchell J; Jackson G; Owen R; Drayson M; Cook G; Jones JR; Pawlyn C; Davies FE; Walker BA; Wardell C; Gregory WM; Cairns D; Morgan GJ; Houlston RS; Kaiser MF
[Ad] Endereço:Division of Molecular Pathology and.
[Ti] Título:Neutral tumor evolution in myeloma is associated with poor prognosis.
[So] Source:Blood;130(14):1639-1643, 2017 Oct 05.
[Is] ISSN:1528-0020
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Recent studies suggest that the evolutionary history of a cancer is important in forecasting clinical outlook. To gain insight into the clonal dynamics of multiple myeloma (MM) and its possible influence on patient outcomes, we analyzed whole exome sequencing tumor data for 333 patients from Myeloma XI, a UK phase 3 trial and 434 patients from the CoMMpass study, all of which had received immunomodulatory drug (IMiD) therapy. By analyzing mutant allele frequency distributions in tumors, we found that 17% to 20% of MM is under neutral evolutionary dynamics. These tumors are associated with poorer patient survival in nonintensively treated patients, which is consistent with the reduced therapeutic efficacy of microenvironment-modulating IMiDs. Our findings provide evidence that knowledge of the evolutionary history of MM has relevance for predicting patient outcomes and personalizing therapy.
[Mh] Termos MeSH primário: Frequência do Gene
Fatores Imunológicos/uso terapêutico
Mieloma Múltiplo/tratamento farmacológico
Mieloma Múltiplo/genética
Mutação
Talidomida/análogos & derivados
Talidomida/uso terapêutico
[Mh] Termos MeSH secundário: Exoma/efeitos dos fármacos
Feminino
Deriva Genética
Seres Humanos
Imunossupressores/uso terapêutico
Estimativa de Kaplan-Meier
Masculino
Mieloma Múltiplo/diagnóstico
Mieloma Múltiplo/patologia
Prognóstico
Microambiente Tumoral/efeitos dos fármacos
[Pt] Tipo de publicação:CLINICAL TRIAL, PHASE III; JOURNAL ARTICLE; RANDOMIZED CONTROLLED TRIAL
[Nm] Nome de substância:
0 (Immunologic Factors); 0 (Immunosuppressive Agents); 4Z8R6ORS6L (Thalidomide); F0P408N6V4 (lenalidomide)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171013
[Lr] Data última revisão:
171013
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170823
[St] Status:MEDLINE
[do] DOI:10.1182/blood-2016-11-750612


  7 / 1882 MEDLINE  
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[PMID]:28782792
[Au] Autor:Yao HB; Tang S; Yao X; Yeh HY; Zhang W; Xie Z; Du Q; Ma L; Wei S; Gong X; Zhang Z; Li Q; Xu B; Zhang HQ; Chen G; Wang CC
[Ad] Endereço:Key Laboratory of Evidence Science of Gansu Province, Gansu Institute of Political Science and Law, Lanzhou, 730070, China.
[Ti] Título:The genetic admixture in Tibetan-Yi Corridor.
[So] Source:Am J Phys Anthropol;164(3):522-532, 2017 Nov.
[Is] ISSN:1096-8644
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:OBJECTIVES: The Tibetan-Yi Corridor located on the eastern edge of Tibetan Plateau is suggested to be the key region for the origin and diversification of Tibeto-Burman speaking populations and the main route of the peopling of the Plateau. However, the genetic history of the populations in the Corridor is far from clear due to limited sampling in the northern part of the Corridor. MATERIALS AND METHODS: We collected blood samples from 10 Tibetan and 10 Han Chinese individuals from Gansu province and genotyped about 600,000 genome-wide single nucleotide polymorphisms (SNPs). RESULTS: Our data revealed that the populations in the Corridor are all admixed on a genetic cline of deriving ancestry from Tibetans on the Plateau and surrounding lowland East Asians. The Tibetan and Han Chinese groups in the north of the Plateau show significant evidence of low-level West Eurasian admixture that could be probably traced back to 600∼900 years ago. DISCUSSION: We conclude that there have been huge population migrations from surrounding lowland onto the Tibetan Plateau via the Tibetan-Yi Corridor since the initial formation of Tibetans probably in Neolithic Time, which leads to the current genetic structure of Tibeto-Burman speaking populations.
[Mh] Termos MeSH primário: Grupo com Ancestrais do Continente Asiático/genética
Fluxo Gênico/genética
Deriva Genética
[Mh] Termos MeSH secundário: Antropologia Física
Feminino
Genética Populacional
Migração Humana
Seres Humanos
Masculino
Polimorfismo de Nucleotídeo Único/genética
Tibet
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171030
[Lr] Data última revisão:
171030
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170808
[St] Status:MEDLINE
[do] DOI:10.1002/ajpa.23291


  8 / 1882 MEDLINE  
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[PMID]:28756116
[Au] Autor:Nguyen LT; Nishi T; Shichinohe S; Chu DH; Hiono T; Matsuno K; Okamatsu M; Kida H; Sakoda Y
[Ad] Endereço:Laboratory of Microbiology, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, North 18, West 9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan; Department of Veterinary Medicine, College of Agriculture and Applied Biology, Can Tho University, Campus II, 3/2 stre
[Ti] Título:Selection of antigenic variants of an H5N1 highly pathogenic avian influenza virus in vaccinated chickens.
[So] Source:Virology;510:252-261, 2017 Oct.
[Is] ISSN:1096-0341
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Vaccination-primed immunity in poultry has been suggested for selection of antigenically drifted highly pathogenic avian influenza viruses (HPAIVs). In this study, we performed two consecutive passage studies of an H5N1 HPAIV in vaccinated chickens, namely, study-I and study-II, to select antigenic variants under immune pressure from the vaccination. In study-I, nine consecutive passages of a wild-type H5N1 HPAIV were carried out in chickens vaccinated with the homologous challenge strain. Antigenically drifted variants with mutations at position 179 in the hemagglutinin (HA) were selected after three passages. Similarly, in study-II, a vaccination-mediated antigenic variant isolated in study-I was used as the vaccine and challenge strain to confirm further antigenic drift after updating the vaccine; after the third passage, additional antigenic variants with a mutation at position 256 in the HA were selected. Thus, our study demonstrated the contribution of vaccination in the selection of antigenic variants of H5 HPAIVs in chickens.
[Mh] Termos MeSH primário: Variação Antigênica
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética
Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia
Vírus da Influenza A Subtipo H5N1/genética
Vírus da Influenza A Subtipo H5N1/imunologia
Influenza Aviária/virologia
[Mh] Termos MeSH secundário: Animais
Galinhas
Deriva Genética
Vírus da Influenza A Subtipo H5N1/isolamento & purificação
Mutação
Seleção Genética
Inoculações Seriadas
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hemagglutinin Glycoproteins, Influenza Virus); 0 (hemagglutinin, avian influenza A virus)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170829
[Lr] Data última revisão:
170829
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170731
[St] Status:MEDLINE


  9 / 1882 MEDLINE  
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[PMID]:28686610
[Au] Autor:Balazik MT; Farrae DJ; Darden TL; Garman GC
[Ad] Endereço:Center for Environmental Studies, Virginia Commonwealth University, Richmond, Virginia.
[Ti] Título:Genetic differentiation of spring-spawning and fall-spawning male Atlantic sturgeon in the James River, Virginia.
[So] Source:PLoS One;12(7):e0179661, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus, Acipenseridae) populations are currently at severely depleted levels due to historic overfishing, habitat loss, and pollution. The importance of biologically correct stock structure for effective conservation and management efforts is well known. Recent improvements in our understanding of Atlantic sturgeon migrations, movement, and the occurrence of putative dual spawning groups leads to questions regarding the true stock structure of this endangered species. In the James River, VA specifically, captures of spawning Atlantic sturgeon and accompanying telemetry data suggest there are two discrete spawning groups of Atlantic sturgeon. The two putative spawning groups were genetically evaluated using a powerful microsatellite marker suite to determine if they are genetically distinct. Specifically, this study evaluates the genetic structure, characterizes the genetic diversity, estimates effective population size, and measures inbreeding of Atlantic sturgeon in the James River. The results indicate that fall and spring spawning James River Atlantic sturgeon groups are genetically distinct (overall FST = 0.048, F'ST = 0.181) with little admixture between the groups. The observed levels of genetic diversity and effective population sizes along with the lack of detected inbreeding all indicated that the James River has two genetically healthy populations of Atlantic sturgeon. The study also demonstrates that samples from adult Atlantic sturgeon, with proper sample selection criteria, can be informative when creating reference population databases. The presence of two genetically-distinct spawning groups of Atlantic sturgeon within the James River raises concerns about the current genetic assignment used by managers. Other nearby rivers may also have dual spawning groups that either are not accounted for or are pooled in reference databases. Our results represent the second documentation of genetically distinct dual spawning groups of Atlantic sturgeon in river systems along the U.S. Atlantic coast, suggesting that current reference population database should be updated to incorporate both new samples and our increased understanding of Atlantic sturgeon life history.
[Mh] Termos MeSH primário: Peixes/genética
Genética Populacional
Repetições de Microssatélites/genética
[Mh] Termos MeSH secundário: Animais
Conservação dos Recursos Naturais
Espécies em Perigo de Extinção
Deriva Genética
Variação Genética
Masculino
Rios
Estações do Ano
Virginia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171004
[Lr] Data última revisão:
171004
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170708
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0179661


  10 / 1882 MEDLINE  
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[PMID]:28658255
[Au] Autor:Malato G; Shervette VR; Navarrete Amaya R; Valdiviezo Rivera J; Nugra Salazar F; Calle Delgado P; Karpan KC; Aguirre WE
[Ad] Endereço:Department of Biological Sciences, DePaul University, Chicago, Illinois, United States of America.
[Ti] Título:Parallel body shape divergence in the Neotropical fish genus Rhoadsia (Teleostei: Characidae) along elevational gradients of the western slopes of the Ecuadorian Andes.
[So] Source:PLoS One;12(6):e0179432, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Neotropical mountain streams are important contributors of biological diversity. Two species of the characid genus Rhoadsia differing for an ecologically important morphological trait, body depth, have been described from mountain streams of the western slopes of the Andes in Ecuador. Rhoadsia altipinna is a deeper-bodied species reported from low elevations in southwestern Ecuador and northern Peru, and Rhoadsia minor is a more streamlined species that was described from high elevations (>1200 m) in the Esmeraldas drainage in northwestern Ecuador. Little is known about these species and their validity as distinct species has been questioned. In this study, we examine how their body shape varies along replicated elevational gradients in different drainages of western Ecuador using geometric morphometrics and the fineness ratio. We also use sequences of the mitochondrial cytochrome oxidase c I gene and the second intron of the S7 nuclear gene to examine whether genetic data are consistent with the existence of two species. We found that body depth varies continuously among populations within drainages as a function of elevation, and that body shape overlaps among drainages, such that low elevation populations of R. minor in the Esmeraldas drainage have similar body depths to higher elevation R. altipinna in southern drainages. Although a common general trend of declining body depth with elevation is clear, the pattern and magnitude of body shape divergence differed among drainages. Sequencing of mitochondrial and nuclear genes failed to meet strict criteria for the recognition of two species (e.g., reciprocal monophyly and deep genetic structure). However, there was a large component of genetic variation for the COI gene that segregated among drainages, indicating significant genetic divergence associated with geographic isolation. Continued research on Rhoadsia in western Ecuador may yield significant insight into adaptation and speciation in Neotropical mountain streams.
[Mh] Termos MeSH primário: Altitude
Tamanho Corporal/fisiologia
Characidae/anatomia & histologia
[Mh] Termos MeSH secundário: Animais
Characidae/genética
Equador
Complexo IV da Cadeia de Transporte de Elétrons/genética
Fluxo Gênico
Deriva Genética
Variação Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
EC 1.9.3.1 (Electron Transport Complex IV)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170920
[Lr] Data última revisão:
170920
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170629
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0179432



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