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1.
J Phycol ; 56(3): 592-607, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32159226

RESUMO

Distributed in tropical and warm-temperate waters worldwide, Lobophora species are found across the Greater Caribbean (i.e., Caribbean sensu stricto, Gulf of Mexico, Florida, the Bahamas, and Bermuda). We presently discuss the diversity, ecology, biogeography, and evolution of the Greater Caribbean Lobophora species based on previous studies and an extensive number of samples collected across the eastern, southern, and to a lesser extent western Caribbean. A total of 18 Lobophora species are now documented from the Greater Caribbean, of which five are newly described (L. agardhii sp. nov., L. dickiei sp. nov., L. lamourouxii sp. nov., L. richardii sp. nov., and L. setchellii sp. nov.). Within the Greater Caribbean, the eastern Caribbean and the Central Province are the most diverse ecoregion and province (16 spp.), respectively. Observed distribution patterns indicate that Lobophora species from the Greater Caribbean have climate affinities (i.e., warm-temperate vs. tropical affinities). In total, 11 Lobophora species exclusively occur in the Greater Caribbean; six are present in the western Atlantic; two in the Indo-Pacific; and one in the eastern Pacific. Biogeographic analyses support that no speciation occurred across the Isthmus of Panama, and that the Greater Caribbean acted as a recipient region for species from the Indo-Pacific and as a region of diversification as well as a donor region to the North-eastern Atlantic. The Greater Caribbean is not an evolutionary dead end for Lobophora, but instead generates and exports diversity. Present results illustrate how sampling based on DNA identification is reshaping biogeographic patterns, as we know them.


Assuntos
Phaeophyceae , Região do Caribe , Ecologia , Florida , Golfo do México , Filogenia
2.
J Phycol ; 55(3): 611-624, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30805921

RESUMO

Lobophora is a common tropical to temperate genus of brown algae found in a plethora of habitats including shallow and deep-water coral reefs, rocky shores, mangroves, seagrass beds, and rhodoliths beds. Recent molecular studies have revealed that Lobophora species diversity has been severely underestimated. Current estimates of the species numbers range from 100 to 140 species with a suggested center of diversity in the Central Indo-Pacific. This study used three molecular markers (cox3, rbcL, psbA), different single-marker species delimitation methods (GMYC, ABGD, PTP), and morphological evidence to evaluate Lobophora species diversity in the Western Atlantic and the Eastern Pacific oceans. Cox3 provided the greatest number of primary species hypotheses(PSH), followed by rbcL and then psbA. GMYC species delimitation analysis was the most conservative across all three markers, followed by PTP, and then ABGD. The most informative diagnostic morphological characters were thallus thickness and number of cell layers in both the medulla and the dorsal/ventral cortices. Following a consensus approach, 14 distinct Lobophora species were identified in the Western Atlantic and five in the Eastern Pacific. Eight new species from these two oceans were herein described: L. adpressa sp. nov., L. cocoensis sp. nov., L. colombiana sp. nov., L. crispata sp. nov., L. delicata sp. nov., L. dispersa sp. nov., L. panamensis sp. nov., and L. tortugensis sp. nov. This study showed that the best approach to confidently identify Lobophora species is to analyze DNA sequences (preferably cox3 and rbcL) followed by comparative morphological and geographical assessment.


Assuntos
Phaeophyceae , Recifes de Corais , Geografia , Oceano Pacífico , Filogenia
3.
Mol Phylogenet Evol ; 110: 81-92, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28279809

RESUMO

The tropical to warm-temperate marine brown macroalgal genus Lobophora (Dictyotales, Phaeophyceae) recently drew attention because of its striking regional diversity. In this study we reassess Lobophora global species diversity, and species distributions, and explore how historical factors have shaped current diversity patterns. We applied a series of algorithmic species delineation techniques on a global mitochondrial cox3 dataset of 598 specimens, resulting in an estimation of 98-121 species. This diversity by far exceeds traditional diversity estimates based on morphological data. A multi-locus time-calibrated species phylogeny using a relaxed molecular clock, along with DNA-confirmed species distribution data was used to analyse ancestral area distributions, dispersal-vicariance-founder events, and temporal patterns of diversification under different biogeographical models. The origin of Lobophora was estimated in the Upper Cretaceous (-75 to -60 MY), followed by gradual diversification until present. While most speciation events were inferred within marine realms, founder events also played a non-negligible role in Lobophora diversification. The Central Indo-Pacific showed the highest species diversity as a result of higher speciation events in this region. Most Lobophora species have small ranges limited to marine realms. Lobophora probably originated in the Tethys Sea and dispersed repeatedly in the Atlantic (including the Gulf of Mexico) and Pacific Oceans. The formation of the major historical marine barriers (Terminal Tethyan event, Isthmus of Panama, Benguela upwelling) did not act as important vicariance events. Long-distance dispersal presumably represented an important mode of speciation over evolutionary time-scales. The limited geographical ranges of most Lobophora species, however, vouch for the rarity of such events.


Assuntos
Phaeophyceae/classificação , Filogenia , Filogeografia , Alga Marinha/classificação , Animais , Biodiversidade , Especificidade da Espécie , Simpatria , Fatores de Tempo
4.
Curr Biol ; 30(7): 1199-1206.e2, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32109397

RESUMO

Extreme events have profound ecological impacts on species and ecosystems, including range contractions and collapse of entire ecosystems. Although theory predicts that extreme events cause loss of genetic diversity, empirical demonstrations are rare, obscuring implications for future adaptive capacity of species and populations. Here, we use rare genetic data from before an extreme event to empirically demonstrate massive and cryptic loss of genetic diversity across ∼800 km of underwater forests following the most severe marine heatwave on record. Two forest-forming seaweeds (Sargassum fallax and Scytothalia dorycarpa) lost ∼30%-65% of average genetic diversity within the 800-km footprint of the heatwave and up to 100% of diversity at some sites. Populations became dominated by single haplotypes that were often not dominant or present prior to the heatwave. Strikingly, these impacts were cryptic and not reflected in measures of forest cover used to determine ecological impact of the heatwave. Our results show that marine heatwaves can drive strong loss of genetic diversity, which may compromise adaptability to future climatic change.


Assuntos
Calor Extremo/efeitos adversos , Variação Genética , Aquecimento Global , Phaeophyceae/genética , Alga Marinha/genética , Oceanos e Mares , Sargassum/genética , Austrália Ocidental
5.
Artigo em Inglês | MEDLINE | ID: mdl-30301868

RESUMO

Endometrial cancer is the most common gynecologic malignancy in industrialized countries, and both its incidence and its associated mortality are increasing. The "liquid biopsy" is becoming an important transformative precision oncology tool, but barriers intrinsic to blood sampling have limited its use in early cancer detection. We hypothesized that using a more targeted sample for analysis-namely, a uterine lavage-should provide a more sensitive and specific diagnostic test for endometrial cancer. Using a custom 12-gene endometrial cancer panel, molecular analysis of uterine lavage fluid from an asymptomatic 67-yr-old female without histopathologic evidence of premalignant lesions or cancer in her uterine tissue revealed two oncogenic PTEN mutations. Ten months later, the patient returned with postmenopausal bleeding and a single microscopic focus of endometrial cancer. DNA isolated and sequenced from laser-capture microdissected tumor tissue revealed the same two PTEN mutations. These mutations were unlikely to occur by chance alone (P < 3 × 10-7). This illustrative case provides the first demonstration that future, tumor-specific mutations can be identified in an asymptomatic individual without clinical or pathologic evidence of cancer by using already established sequencing technologies but targeted sampling methods. This finding provides the basis for new opportunities in early cancer screening, detection, and prevention.


Assuntos
Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/genética , Neoplasias dos Genitais Femininos/diagnóstico , Idoso , Biópsia , Endométrio/metabolismo , Feminino , Humanos , Biópsia Líquida/métodos , Mutação , PTEN Fosfo-Hidrolase/genética , Pós-Menopausa , Medicina de Precisão , Irrigação Terapêutica/métodos , Hemorragia Uterina , Útero/citologia
6.
Sci Rep ; 7: 45850, 2017 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-28368049

RESUMO

Rhodoliths are benthic calcium carbonate nodules accreted by crustose coralline red algae which recently have been identified as useful indicators of biomineral changes resulting from global climate change and ocean acidification. This study highlights the discovery that the interior of rhodoliths are marine biodiversity hotspots that function as seedbanks and temporary reservoirs of previously unknown stages in the life history of ecologically important dinoflagellate and haptophyte microalgae. Whereas the studied rhodoliths originated from offshore deep bank pinnacles in the northwestern Gulf of Mexico, the present study opens the door to assess the universality of endolithic stages among bloom-forming microalgae spanning different phyla, some of public health concerns (Prorocentrum) in marine ecosystems worldwide.


Assuntos
Biodiversidade , Ecossistema , Eucariotos/fisiologia , Rodófitas/fisiologia , Carbonato de Cálcio/metabolismo , Mudança Climática , Golfo do México , Biologia Marinha
7.
Acta neurol. colomb ; 22(3): 269-277, jul.-sept. 2006.
Artigo em Espanhol | LILACS | ID: lil-440010

RESUMO

El envejecimiento de la población se acompaña de un dramático aumento en la prevalencia de la depresión y la demencia. Múltiples estudios señalan que la depresión puede presentarse entre el 30-50 por ciento de los pacientes con demencia La depresión mayor puede ocurrir en el 12 por ciento de los pacientes con demencia, y más de un 30 por ciento de los pacientes con enfermedad de Alzheimer presentan a lo largo de su enfermedad un síntoma depresivo. Los pacientes con elementos depresivos secundarios a un ataque cerebrovascular (“depresión vascular” de acuerdo a Steffens) y con lesiones subcorticales en las neuroimágenes, presentan síntomas depresivos y deterioro cognoscitivo progresivo y episodios confusionales. La compleja asociación entre depresión y demencia favorece la presencia de agitación, alucinaciones y vagabundeo; la mejoría de los síntomas depresivos en pacientes con demencia evita estas alteraciones. Los síntomas depresivos no reflejan necesariamente la presencia de una depresión mayor, pudiendo corresponder a una manifestación clínica de un cuadro demencial. En la propuesta de Staus la relación del hombre con su entorno, se basa en la acumulación de elementos paisajísticos (o afectivos) y geográficos (o cognoscitivos), la demencia aparece en cuanto pierden los elementos geográficos, la depresión cuando se pierden los paisajísticos


Assuntos
Humanos , Demência , Depressão , Envelhecimento
8.
J. bras. ortodon. ortop. facial ; 5(27): 35-38, maio-jun. 2000. ilus
Artigo em Português | LILACS, BBO | ID: lil-428026

RESUMO

Realizou-se um estudo comparativo entre os valores da tabela de Moyers ao nível de 50% (utilizado em Cuba) e comparou-se com os valores preconizados por Tanaka e Johnston que se adaptam mais à esta população por utilizar os valores reais da largura mesiodistal dos incisivos inferiores, tendo uma constante de 0,5 mm entre a largura mesiodistal de 345 inferior com relação a 345 superio. Moyers apresenta 0,6 mm, pelo que se considera não significativo. Tanaka e johnston não precisam de tabelas de referências, como é o caso da tabela de Moyers, além disso, pelas características do seu método, metade da largura mesiodistial dos 4 incisivos inferiores + 10,5 mm, é semelhante à largura dos caninos e dos pré-molares inferiores de um quadrado. A metade da largura mesiodistal dos 4 incisivos inferiores + 11 mm é igual à largura dos caninos e dos pré-molares de um quadrado, pelo que não é necessário fazer aproximações, como é o caso da tabela de Moyers. O métido de Tanaka e Johnston é muito simples e exato


Assuntos
Estudo de Avaliação , Ortodontia Corretiva , Fechamento de Espaço Ortodôntico , Técnica de Expansão Palatina
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