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1.
PLoS One ; 15(7): e0235288, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614920

RESUMO

The American crocodile (Crocodylus acutus) is a widely distributed species across coastal and brackish areas of the Neotropical region of the Americas and the Greater Antilles. Available information on patterns of genetic differentiation in C. acutus shows a complex structuring influenced by interspecific interactions (mainly hybridization) and anthropogenic actions (mostly historical hunting, recent poaching, habitat loss and fragmentation, and unintentional translocation of individuals). In this study, we used data on mitochondrial DNA control region and 11 nuclear polymorphic microsatellite loci to assess the degree of population structure of C. acutus in South America, North America, Central America and the Greater Antilles. We used traditional genetic differentiation indices, Bayesian clustering and multivariate methods to create a more comprehensive picture of the genetic relationships within the species across its range. Analyses of mtDNA and microsatellite loci show evidence of a strong population genetic structure in the American crocodile, with unique populations in each sampling locality. Our results support previous findings showing large degrees of genetic differentiation between the continental and the Greater Antillean C. acutus. We report three new haplotypes unique to Venezuela, which are considerably less distant from the Central and North American haplotypes than to the Greater Antillean ones. Our findings reveal genetic population differentiation between Cuban and Jamaican C. acutus and offer the first evidence of strong genetic differentiation among the populations of Greater Antillean C. acutus.


Assuntos
Jacarés e Crocodilos/genética , Animais , Região do Caribe , América Central , DNA Mitocondrial/genética , Variação Genética , Genética Populacional , Haplótipos , Repetições de Microssatélites , Mitocôndrias/genética , América do Norte , América do Sul
2.
Bol. micol. (Valparaiso En linea) ; 33(2): 17-29, dic. 2018. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-1008160

RESUMO

Plantaciones de teca (Tectona grandis L.f.) en Ecuador están siendo afectadas por una compleja enfermedad de marchitez vascular y muerte regresiva, con características epidémicas, sin que hasta el momento se conozca el o los agentes causales. Se planteó describir la sintomatología de la enfermedad e identificar los hongos fitopatógenos asociados a árboles enfermos en el Trópico Húmedo Ecuatoriano mediante morfofisiología. Se seleccionaron tres plantaciones de 2, 5 y 7 años de edad, en cada una se delimitó tres parcelas de 500 m2. Se realizó la descripción sintomatológica, evaluó la incidencia y severidad de la enfermedad empleando una escala de cinco categorías. Por parcela se diseccionaron tres árboles, cuyos tejidos se llevaron al laboratorio, donde se emplearon tres estrategias metodológicas (cámara húmeda, sandwiches de zanahoria, y medio de cultivo papa-dextrosa-agar; PDA) para estimular la expresión de los fitopatógenos. En árboles enfermos se detectó clorosis, pérdida de turgencia, ápices de crecimiento secos, emisión de brotes epicormicos en el fuste, y marchitez fulminante. Se aisló e identificó Ceratocystis fimbriata Ellis & Halst., y especies de Fusarium de forma consecutiva con las tres estrategias metodológicas empleadas. La incidencia de la enfermedad fue del 16.6%, 15.2%, y 11.6% para las plantaciones de 2, 5 y 7 años, respectivamente. Los árboles enfermos en la plantación de 2 años se encontraron en las escalas 2, 4 y 5, mientras que en plantaciones de 5 y 7 años se ubicaron en las escalas 2, 3 y 5 de progreso de la enfermedad...(AU)


Teak plantations (Tectona grandis L. f.) in Ecuador are being affected by a complex disease of vascular wilt and dieback, with epidemic characteristics, without knowing the causal agent(s) so far. We proposed to describe the symptomatology of the disease and identify phytopathogenic fungi associated with diseased trees in the Ecuadorian Humid Tropic by morphophysiology. Three plantations of 2, 5 and 7 years of age were selected, in each three plots of 500 m2 were delimited. The symptomatologic description was made, evaluated the incidence and severity of the disease using a scale of five categories. By plot, three trees were dissected, whose tissues were taken to the laboratory, where three methodological strategies were used (wet chamber, carrot sandwiches, and potatodextrose-agar culture medium, PDA) to stimulate the expression of phytopathogens. In diseased trees, chlorosis, turgor loss, dry growth apices, emission of epicormic shoots in the stem, and fulminating wilt were detected. It was isolated and identified Ceratocystis fimbriata Ellis & Halst., and Fusarium species. consecutively with the three methodological strategies employed. The incidence of the disease was 16.6%, 15.2%, and 11.6% for plantations of 2, 5 and 7 years, respectively. The sick trees in the plantation of 2 years were found in scales 2, 4 and 5, while in plantations of 5 and 7 years they were located in scales 2, 3 and 5 of progress of the disease. ..(AU)


Assuntos
Fusarium/patogenicidade , Necrose e Clorose das Plantas , Ceratocystis/isolamento & purificação , Árvores/microbiologia , Índice de Gravidade de Doença , Incidência , Ecossistema Tropical , Equador , Fungos/patogenicidade
3.
Ecol Evol ; 6(16): 5817-30, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27547357

RESUMO

Transitions between the marine and freshwater macrohabitat have occurred repeatedly in the evolution of teleost fishes. For example, ariid catfishes have moved from freshwater to marine environments, and vice versa. Opercles, a skeletal feature that has been shown to change during such transitions, were subjected to 2D geometric morphometric analyses in order to investigate evolutionary shape changes during habitat transition in ariid catfishes and to test the influence of habitat on shape changes. A mtDNA marker, which proved useful in previous studies, was used to verify species identities. It greatly improved the assignment of specimens to a species, which are difficult to assign by morphology alone. The application of a mtDNA marker confirmed the occurrence of Notarius biffi in Central America, South of El Salvador. Molecular identification together with principal component analysis (PCA) and further morphological inspection of neurocrania indicated the existence of a cryptic species within Bagre pinnimaculatus. Principal component (PC) scores of individual specimens clustered in morphospace by genus rather than by habitat. Strong phylogenetic structure was detected using a permutation test of PC scores of species means on a phylogenetic tree. Calculation of Pagel's λ suggested that opercle shape evolved according to a Brownian model of evolution. Yet canonical variate analysis (CVA) conducted on the habitat groups showed significant differences in opercle shapes among freshwater and marine species. Overall, opercle shape in tropical American Ariidae appears to be phylogenetically constrained. This verifies the application of opercle shape as a taxonomic tool for species identification in fossil ariid catfishes. At the same time, adaptation to freshwater habitats shows characteristic opercle shape trajectories in ariid catfishes, which might be used to detect habitat preferences in fossils.

4.
J. bras. psiquiatr ; 44(6): 283-286, jun. 1995. tab, graf
Artigo em Português | LILACS | ID: lil-311143

RESUMO

Os autores apresentam o perfil clínico e características demográficas de uma amostra de 25 pacientes com diagnóstico de fobia social através da aplicação de vários instrumentos e escalas


Assuntos
Humanos , Masculino , Feminino , Sintomatologia , Transtornos Fóbicos/diagnóstico , Alcoolismo , Ansiedade , Depressão , Escolaridade , Anamnese , Escalas de Graduação Psiquiátrica , Fatores Sexuais
5.
RBM rev. bras. med ; 52(2): 11-5, fev. 1995. tab
Artigo em Português | LILACS | ID: lil-152153

RESUMO

Um perfil clinico da fobia social e descrito neste artigo, bem como seu tratamento farmacologico e psicologico


Assuntos
Humanos , Transtornos Fóbicos/classificação , Transtornos Fóbicos/etiologia , Ansiedade/classificação
6.
J. bras. psiquiatr ; 6(44): 283-286, jun. 1995.
Artigo | Index Psicologia - Periódicos | ID: psi-2891

RESUMO

Os autores apresentam o perfil clinico e caracteristicas demograficas de uma amostra de 25 pacientes com diagnostico de fobia social atraves da aplicacao de varios instrumentos e escalas.


Assuntos
Fobia Social , Depressão , Ansiedade , Diagnóstico , Fobia Social , Ansiedade , Diagnóstico
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