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1.
Planta ; 251(3): 72, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32112137

RESUMO

MAIN CONCLUSION: This study provides broad insight into the chloroplast genomes of the subfamily Monsteroideae. The identified polymorphic regions may be suitable for designing unique and robust molecular markers for phylogenetic inference. Monsteroideae is the third largest subfamily (comprises 369 species) and one of the early diverging lineages of the monocot plant family Araceae. The phylogeny of this important subfamily is not well resolved at the species level due to scarcity of genomic resources and suitable molecular markers. Here, we report annotated chloroplast genome sequences of four Monsteroideae species: Spathiphyllum patulinervum, Stenospermation multiovulatum, Monstera adansonii, and Rhaphidophora amplissima. The quadripartite chloroplast genomes (size range 163,335-164,751 bp) consist of a pair of inverted repeats (25,270-25,931 bp), separating a small single copy region (21,448-22,346 bp) from a large single copy region (89,714-91,841 bp). The genomes contain 114 unique genes, including four rRNA genes, 80 protein-coding genes, and 30 tRNA genes. Gene features, amino acid frequencies, codon usage, GC contents, oligonucleotide repeats, and inverted repeats dynamics exhibit similarities among the four genomes. Higher rate of synonymous substitutions was observed as compared to non-synonymous substitutions in 76 protein-coding genes. Positive selection was observed in seven protein-coding genes, including psbK, ndhK, ndhD, rbcL, accD, rps8, and ycf2. Our included species of Araceae showed the monophyly in Monsteroideae and other subfamilies. We report 30 suitable polymorphic regions. The polymorphic regions identified here might be suitable for designing unique and robust markers for inferring the phylogeny and phylogeography among closely related species within the genus Spathiphyllum and among distantly related species within the subfamily Monsteroideae. The chloroplast genomes presented here are a valuable contribution towards understanding the molecular evolutionary dynamics in the family Araceae.

2.
Genomics ; 112(3): 2349-2360, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31945463

RESUMO

Aroideae is the largest and most diverse subfamily of the plant family Araceae. Despite its agricultural and horticultural importance, the genomic resources are sparse for this subfamily. Here, we report de novo assembled and fully annotated chloroplast genomes of 13 Aroideae species. The quadripartite chloroplast genomes (size range of 158,177-170,037 bp) are comprised of a large single copy (LSC; 75,594-94,702 bp), a small single copy (SSC; 12,903-23,981 bp) and a pair of inverted repeats (IRs; 25,266-34,840 bp). Notable gene rearrangements and IRs contraction / expansions were found for Anchomanes hookeri and Zantedeschia aethiopica. Codon usage, amino acid frequencies, oligonucleotide repeats, GC contents, and gene features revealed similarities among the 13 species. The number of oligonucleotide repeats was uncorrelated with genome size or phylogenetic position of the species. Phylogenetic analyses corroborated the monophyly of Aroideae but were unable to resolve the positions of Calla and Schismatoglottis.

3.
PhytoKeys ; 135: 21-34, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31736629

RESUMO

Two new species of Chlorospatha (section Orientales) from the western slope of the Cordillera Occidental in the departments of Valle del Cauca and Choco (Colombia) are described here. The new species represent the first records of section Orientales for Colombia, which was previously known only from the eastern Andes in Ecuador. The two new species are similar to C. longipoda, C. hannoniae and C. boosii. Chlorospatha minima sp. nov. is differentiated by its small overall size (less than 30 cm tall), blade strongly inequilateral with smooth adaxial surface, and spadix less than 2.2 cm long. Chlorospatha silverstonei sp. nov. is differentiated by its large overall size (30-60 cm tall), 1-3 leaves per plant, and quilted adaxial blade surface.

4.
Am J Bot ; 105(11): 1888-1910, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30368769

RESUMO

PREMISE OF THE STUDY: We present the first plastome phylogeny encompassing all 77 monocot families, estimate branch support, and infer monocot-wide divergence times and rates of species diversification. METHODS: We conducted maximum likelihood analyses of phylogeny and BAMM studies of diversification rates based on 77 plastid genes across 545 monocots and 22 outgroups. We quantified how branch support and ascertainment vary with gene number, branch length, and branch depth. KEY RESULTS: Phylogenomic analyses shift the placement of 16 families in relation to earlier studies based on four plastid genes, add seven families, date the divergence between monocots and eudicots+Ceratophyllum at 136 Mya, successfully place all mycoheterotrophic taxa examined, and support recognizing Taccaceae and Thismiaceae as separate families and Arecales and Dasypogonales as separate orders. Only 45% of interfamilial divergences occurred after the Cretaceous. Net species diversification underwent four large-scale accelerations in PACMAD-BOP Poaceae, Asparagales sister to Doryanthaceae, Orchidoideae-Epidendroideae, and Araceae sister to Lemnoideae, each associated with specific ecological/morphological shifts. Branch ascertainment and support across monocots increase with gene number and branch length, and decrease with relative branch depth. Analysis of entire plastomes in Zingiberales quantifies the importance of non-coding regions in identifying and supporting short, deep branches. CONCLUSIONS: We provide the first resolved, well-supported monocot phylogeny and timeline spanning all families, and quantify the significant contribution of plastome-scale data to resolving short, deep branches. We outline a new functional model for the evolution of monocots and their diagnostic morphological traits from submersed aquatic ancestors, supported by convergent evolution of many of these traits in aquatic Hydatellaceae (Nymphaeales).


Assuntos
Especiação Genética , Genomas de Plastídeos , Magnoliopsida/genética , Filogenia , DNA Intergênico , Zingiberales/genética
6.
Proc Biol Sci ; 282(1814)2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26311671

RESUMO

Orchids are the most diverse family of angiosperms, with over 25 000 species,more than mammals, birds and reptiles combined. Tests of hypotheses to account for such diversity have been stymied by the lack of a fully resolved broad-scale phylogeny. Here,we provide such a phylogeny, based on 75 chloroplast genes for 39 species representing all orchid subfamilies and 16 of 17 tribes, time-calibrated against 17 angiosperm fossils. Asupermatrix analysis places an additional 144 species based on three plastid genes. Orchids appear to have arisen roughly 112 million years ago (Mya); the subfamilies Orchidoideae and Epidendroideae diverged from each other at the end of the Cretaceous; and the eight tribes and three previously unplaced subtribes of the upper epidendroids diverged rapidly from each other between 37.9 and 30.8 Mya. Orchids appear to have undergone one significant acceleration of net species diversification in the orchidoids, and two accelerations and one deceleration in the upper epidendroids. Consistent with theory, such accelerations were correlated with the evolution of pollinia, the epiphytic habit, CAM photosynthesis, tropical distribution (especially in extensive cordilleras),and pollination via Lepidoptera or euglossine bees. Deceit pollination appears to have elevated the number of orchid species by one-half but not via acceleration of the rate of net diversification. The highest rate of net species diversification within the orchids (0.382 sp sp(-1) My(-1)) is 6.8 times that at the Asparagales crown.


Assuntos
Evolução Biológica , Orchidaceae/classificação , Orchidaceae/genética , Filogenia , Animais , Abelhas , Cloroplastos/genética , Decepção , Genoma de Planta , Lepidópteros , Fotossíntese , Polinização/genética , Fatores de Tempo
7.
Ear Nose Throat J ; 93(8): E22-4, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25181670

RESUMO

Paragangliomas are uncommon tumors that arise from the parasympathetic neuroectodermal ganglionic cells and have been described in numerous anatomic locations, most commonly in the abdomen. Head and neck paragangliomas are classified into carotid body (most common), vagal, and jugulotympanic types. Computed tomography is the initial imaging modality of choice for the preoperative assessment of the extent of paragangliomas. Magnetic resonance imaging and selective angiography provide more detail of the surrounding tissues and vasculature. Surgical resection is the treatment of choice.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Paraganglioma/diagnóstico , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
8.
Rev. bras. ecocardiogr. imagem cardiovasc ; 26(1): 52-55, jan.-mar.2013. ilus
Artigo em Português | LILACS | ID: lil-663442

RESUMO

Apresentamos um relato de caso no qual o diagnóstico de ausência congênita do pericárdio (ACP) foi, inicialmente, suspeito na análise ecocardiográfica bidimensional, devido à presença do ápice posterior deslocado na janela das quatro câmaras na direção da linha axilar média. Posteriormente, o diagnóstico foi confirmado por um raio-x do tórax, ressonância magnética e tomografia computadorizada do tórax.


We report a case in which the diagnosis of congenital absence of the pericardium (ACP) was initially suspected in two-dimensional echocardiographic analysis due to the presence of the apex later moved in the window of the four chambers in the direction of the midaxillary line. Subsequently, the diagnosis was confirmed by a chest x-ray, magnetic resonance imaging and computed tomography.


Assuntos
Humanos , Masculino , Adulto , Cardiopatias Congênitas/complicações , Ecocardiografia/métodos , Pericárdio , Taquicardia/complicações
9.
Rev. colomb. radiol ; 17(1): 1868-1887, mar. 2006. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-521537

RESUMO

La cardiotomografía computada (CTC) es una modalidad diagnóstica en constante evolución que incluye un número de exámenes que permiten evaluar la anatomía y la patología de los grandes vasos del tórax, del corazón y del pericardio. En la actualidad, con los equipos de tomografía computarizada multicorte (multidetectores) de última generación —con una mayor cantidad de filas de detectores, colimación más fina, mayor rapidez, habilidad de realizar estudios acoplados al trazo electrocardiográfico y posibilidad de modulación de la dosis de radiación— se puede realizar de una manera confiable, precisa y rápida la evaluación de las arterias coronarias, de la placa arteriosclerótica y de la función cardiaca. Una adecuada selección y preparación de los pacientes son requisitos fundamentales para obtener estudios diagnósticos de la más alta calidad.


Assuntos
Humanos , Vasos Coronários , Coração , Pericárdio , Tomografia
10.
Rev. colomb. radiol ; 13(3): 1179-1188, sept. 2002. ilus
Artigo em Espanhol | LILACS | ID: lil-346362

RESUMO

Este artículo de revisión describe la Tomografía Helicoidal sin contraste del árbol urinario o Uro-TAC, analiza susventajas y desventajas y expone el protocolo para su realización. El Uro - TAC Es una modalidad diagnóstica rápida que no requiere preparación antes del examen ni la administración de contraste oral o intravenoso, evitando riesgos y costos inherentes a los mismos. Es efectivo en la identificación de los cálculos ureterales. independiente de su composición proporcionando, información volumétrica, lo que evita artificios de volumen parcial. Es una técnica independiente del operador y no se afecta por la constitución del paciente. El examen en sí tiene una curva de aprendizaje breve , después de la cual, la interpretación de las imágenes es rápida y sencilla. Permite además el diagnóstico de otras patologías diferentes a las litiasis, que pueden ser las causantes de dolor abdominal. Entre sus desventajas se exponen y analizan la dosis de radiación sus costos y la valoración limitada del grado de obstrucción ureteral


Assuntos
Cálculos Urinários/diagnóstico , Tomografia
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