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1.
PLoS One ; 18(12): e0296335, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38153939

RESUMEN

Stelliferinae is the third most speciose subfamily of Sciaenidae, with 51 recognized species arranged in five genera. Phylogenies derived from both morphological and molecular data support the monophyly of this subfamily, although there is no general consensus on the intergeneric relationships or the species diversity of this group. We used the barcoding region of the cytochrome oxidase C subunit I (COI) gene to verify the delimitation of Stelliferinae species based on the Automatic Barcode Gap Discovery (ABGD), Generalized Mixed Yule Coalescence (GMYC), and Bayesian Poisson Tree Process (bPTP) methods. In general, the results of these different approaches were congruent, delimiting 30-32 molecular operational taxonomic units (MOTUs), most of which coincided with valid species. Specimens of Stellifer menezesi and Stellifer gomezi were attributed to a single species, which disagrees with the most recent review of this genus. The evidence also indicated that Odontoscion xanthops and Corvula macrops belong to a single MOTU. In contrast, evidence also indicates presence of distinct lineages in both Odontoscion dentex and Bairdiella chrysoura. Such results are compatible with the existence of cryptic species, which is supported by the genetic divergence and haplotype genealogy. Therefore, the results of the present study indicate the existence of undescribed diversity in the Stelliferinae, which reinforces the need for an ample taxonomic review of the fish in this subfamily.


Asunto(s)
Código de Barras del ADN Taxonómico , Perciformes , Animales , Código de Barras del ADN Taxonómico/métodos , Teorema de Bayes , ADN , Filogenia , Perciformes/genética
2.
PeerJ ; 11: e15364, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37304874

RESUMEN

The catfishes Brachyplatystoma filamentosum (Kumakuma), Brachyplatystoma vaillantii (Laulao catfish), and Brachyplatystoma rousseauxii (gilded catfish) are important fishery resources in Brazil, where they are sold both fresh and in the form of fillets or steaks. These species have morphological similarities, thus, they can be easily misidentified or substituted, especially after processed. Therefore, accurate, sensitive, and reliable methods are needed for the identification of these species to avoid commercial fraud. In the present study, we develop two multiplex PCR assays for the identification of the three catfish species. Each multiplex protocol combined three species-specific forward primers and a universal reverse primer to produce banding patterns able to discriminate the target species unequivocally. The length of the cytochrome C oxidase subunit I (COI) fragments was approximately 254 bp for B. rousseauxii, 405 bp for B. vaillantii, and 466 bp for B. filamentosum, while the control region (CR) assay produced fragments of approximately 290 bp for B. filamentosum, 451 bp for B. vaillantii, and 580 bp for B. rousseauxii. The protocols were sensitive enough to detect the target species at a DNA concentration of 1 ng/µL, with the exception of the CR of B. vaillantii, in which the fragment was only detectable at 10 ng/µL. Therefore, the multiplex assays developed in the present study were sensitive, accurate, efficient, rapid, and cost-effective for the unequivocal identification of the target species of Brachyplatystoma. They can be utilized by fish processing industries to certify their products, or by government agencies to authenticate products and prevent fraudulent commercial substitutions.


Asunto(s)
Bagres , Reacción en Cadena de la Polimerasa Multiplex , Animales , Bagres/genética , Brasil , Análisis Costo-Beneficio , Bioensayo
3.
Food Res Int ; 143: 110308, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33992328

RESUMEN

In Brazil, Cynoscion leiarchus and Plagioscion squamosissimus are the species allowed to be labeled as "pescada-branca". These species have high economic value, especially when sold in the form of fillets. Therefore, when morphological traits are removed, fish are highly prone to be substituted, which has been reported for species of the family Sciaenidae sold in Brazil, including "pescada-branca". We have sequenced 618 bp of the COI of 143 samples to re-evaluate the occurrence of substitutions in frozen "pescada-branca" marketed in Brazil. We observed more than 73% of mislabeling, with only 26.57% being P. squamosissimus, and none, C. leiarchus. In general, the substitutes were closely related Sciaenidae, but cheaper species, which indicates commercial fraud. Based on these results we used 1.2 kb of COI to develop an octaplex PCR assay that unequivocally identified the target species and six substitute species through the banding pattern. Specific reverse primers combined with a universal forward primer were used in the protocol and identified the species C. leiarchus (~290 bp), N. microps (~340 bp), M. ancylodon (~470 bp), C. acoupa (~540 bp), C. microlepidotus (~850 bp), P. auratus (~950 bp), C. virescens (~1050 bp), and P. squamosissimus (~1140 bp). The DNA barcoding and the multiplex PCR were accurate and specific to authenticate processed products labeled as "pescada-branca". The multiplex assay constitutes a cost-effective alternative for the authentication of these products and other sciaenids. Additionally, we suggest that the multiplex assay can be adopted by both companies and regulatory agencies to prevent commercial fraud in the marketing of processed fishery products in Brazil and other countries where these products are commercialized.


Asunto(s)
Código de Barras del ADN Taxonómico , Perciformes , Animales , Factores de Coagulación Sanguínea , Brasil , Reacción en Cadena de la Polimerasa
4.
Heliyon ; 6(9): e04888, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32984598

RESUMEN

The substitution and mislabeling is facilitated by the processing of fish products. We employed a DNA barcoding to authenticate fillets labeled as "dourada" (Brachyplatystoma rousseauxii), and "piramutaba" (Brachyplatystoma vaillantii) marketed in the Brazil. A 615 bp of the Cytochrome oxidase subunit I (COI) was sequenced from 305 fillets and subsequently identified to species level by querying public databases and sequences of reference species. The results revealed a global mean substitution rate of 17%. The highest substitution rate was detected in "dourada" (26%), the most valuable species, followed by "piramutaba" (9%). The most cases of substitutions were by species of lower commercial value, suggesting fraud aimed at increased profits. Therefore, we suggest the improvement of food-labeling regulation, continued inspection, as well as the adoption of the DNA barcode for the molecular authentication of processed fish to prevent substitution of these products in Brazil.

5.
Mol Phylogenet Evol ; 137: 285-292, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31121309

RESUMEN

The genus Hypophthalmus encompasses four valid South American freshwater catfish species: H. marginatus, H. edentatus, H. fimbriatus, and H. oremaculatus. More recently two new species were proposed Hypophthalmus n. sp. 1 and Hypophthalmus n. sp. 2. While Hypophthalmus species are a fundamentally important resource for the commercial fisheries that operate in the continental waters of the Amazon basin, their phylogenetic relationships and the true diversity of the genus have yet to be defined conclusively. Given this, the present study analyzed sequences of the mitochondrial COI gene and four nuclear markers (RAG2, Myh6, Plagl2 and Glyt) to evaluate the phylogenetic relationships and the diversity of the species of this genus. All the analyses showed that Hypophthalmus is monophyletic, and the species delimitation tests recovered all the Hypophthalmus taxa as distinct species. The putative new species Hypophthalmus n. sp. 1 and Hypophthalmus n. sp. 2 presented mean genetic divergence similar to or greater than that observed between valid Hypophthalmus taxa. All the analyses showed that H. oremaculatus is the sister group of H. n. sp. 1, which together group with H. fimbriatus. This clade is the sister group of the clade containing H. edentatus and H. n. sp. 2. One specimen, morphologically identified as H. oremaculatus, presented the nuclear genome of this species and the mitochondrial genome of H. n. sp. 1; while another specimen, morphologically identified as H. n. sp. 2, presented the nuclear Myh6 of H. n. sp. 2 and the mitochondrial and RAG2 genome of H. edentatus. These results indicate that hybridization and introgression has occurred between species in Hypophthalmus. The findings of this study indicate that the diversity of the Hypophthalmus is underestimated, emphasize the need for a taxonomic review of the genus, and a more systematic evaluation of the hybridization patterns found, to understanding the role of hybridization and introgression in the evolution of the genus.


Asunto(s)
Bagres/clasificación , Bagres/genética , Sitios Genéticos , Variación Genética , Filogenia , Animales , Teorema de Bayes , Núcleo Celular/genética , ADN Mitocondrial/genética , Hibridación Genética , Mitocondrias/genética , Especificidad de la Especie
6.
Mol Phylogenet Evol ; 125: 51-61, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29567506

RESUMEN

Phylogenies based on morphological and molecular data confirm the monophyly of the subfamily Stelliferinae; however, there is no consensus on the intergeneric and interspecific relationships in the group. Previous studies suggested the non-monophyly of Ophioscion and Stellifer, and possible cryptic species in Ophioscion punctatissimus. Therefore, we used mitochondrial (16S rDNA and COI) and nuclear (Rhodopsin, EGR1, and RAG1) regions to examine phylogenetic relationships among species of this subfamily. Our results confirmed the monophyly of Stelliferinae and supports the close relationship among Bardiella, Corvula and Odontoscion, which form a sister group to Stellifer and Ophioscion. Notwithstanding, all the results support the non-monophyly of Stellifer and Ophioscion and we suggest that a taxonomic revision should consider Ophioscion as a junior synonym of Stellifer. Moreover, O. punctatissimus was grouped into two clades, with the O. punctatissimus lineage I (LI) being closer to O. scierus from the eastern Pacific than to the O. punctatissimus lineage II (LII). The most recent common ancestor (TMRCA) for the O. scierus and O. punctatissimus LI and O. punctatissimus LII clade dates from 7.2 (HPD: 4.3-10.5) Ma, whereas TMRCA for the O. scierus and O. punctatissimus LI clade dates from 5.3 (HPD: 2.4-8.6) Ma, indicating that speciation processes may be related to the rise of the Isthmus of Panama. Phylogeographic analyses corroborate the hypothesis of speciation in O. punctatissimus. These results suggest that lineages of O. punctatissimus originated from distinct ancestors and, by morphological similarity, were considered the same taxon. A taxonomic revision should be performed to validate the species status of such lineages.


Asunto(s)
Especiación Genética , Perciformes/clasificación , Perciformes/genética , Filogenia , Animales , Océano Atlántico , Teorema de Bayes , ADN Mitocondrial/genética , Variación Genética , Genoma , Panamá , Filogeografía , Especificidad de la Especie , Factores de Tiempo
7.
Porto Alegre; s.n; 2015. 21 p.
Tesis en Portugués | Coleciona SUS | ID: biblio-943024

RESUMEN

Ao mesmo tempo em que a morte aterroriza a humanidade, ela também fascina, despertando fortes discussões quando as pessoas se propõem a falar a respeito. No entanto, ela tem sido encarada por muitos de maneira fria e distanciada. Sendo assim, este projeto tem por objetivo qualificar a assistência prestada pelas equipes do PAD, vinculadas ao Grupo Hospitalar Conceição, às pessoas que optam por morrer em casa. Investigando como os profissionais trabalham o tema da morte com a família e paciente, quais os sentimentos e conflitos que permeiam o imaginário dos profissionais, familiares e pessoas, tendo a casa como espaço de escolha para morrer e quais as dificuldades que os profissionais e familiares encontram para realizar o óbito no domicílio com qualidade. Com a implantação deste projeto de intervenção espera-se que os profissionais da equipe do PAD tenham melhor qualificação para lidar com o tema da morte no domicílio e que a autonomia do paciente sobre o local onde deseja estar em seus últimos momentos de vida seja respeitada.


Asunto(s)
Masculino , Femenino , Humanos , Actitud Frente a la Muerte , Brasil , Muerte , Atención Domiciliaria de Salud , Salud Pública , Sistema Único de Salud
8.
Pensando fam ; 18(2): 62-76, dez. 2014.
Artículo en Portugués | LILACS | ID: lil-747832

RESUMEN

A gestação é um período que possibilita ao pai vivenciar experiências desconhecidas, rever papéis e se adaptar a um novo ciclo. Sendo assim, este artigo tem por objetivo descrever de que forma o homem vivencia a gestação do seu primeiro filho além de conhecer como consideram seu papel enquanto pai durante a gestação. Participaram deste estudo qualitativo cinco pais em que as esposas estavam grávidas, distribuídos nos três trimestres gestacionais. Realizou-se uma entrevista semi-estruturada em que as respostas foram analisadas conforme análise de conteúdo Bardin (1977). Os resultados mostraram que os pais se envolvem de diversas formas com a gestante e o bebê, dispensando apoio material e emocional. Todavia, alguns não conseguem vivenciar com facilidade esta fase, o que nos indica que a gestação ainda é um período no qual os homens estão buscando novas formas de se inteirar e explorar, uma vez que não ocorre em seu próprio corpo.(AU)


Pregnancy gives the father the opportunity to experience the unknown, review his roles and to adapt himself to the new cycle that begins. Thus, this article aims to describe on how men experience the pregnancy of their first child besides finding out how they consider their roles as father during the period of gestation. Took part in this qualitative research five fathers in whose wives were pregnant, distributed on the three gestational trimesters. Was performed a semi-structured interview in which the answers were analyzed according to Bardin content analysis (1977). Results showed that men are involved in several ways with their pregnant woman and the baby, excluding material and emotional support. However , some of them still cannot overcome this period easily, which points to the fact that pregnancy is yet a time where men are seeking for new ways to learn about themselves and to explore it, as it does not take place in their own bodies.(AU)


Asunto(s)
Humanos , Padres/psicología , Paternidad , Embarazo , Investigación Cualitativa , Relaciones Padre-Hijo
9.
PLoS One ; 9(7): e102250, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25020128

RESUMEN

The phylogenetic relationships within the Stellifer group of weakfishes (Stellifer, Odontoscion, Ophioscion, and Bairdiella) were evaluated using 2723 base pairs comprising sequences of nuclear (rhodopsin, TMO-4C4, RAG-1) and mitochondrial (16S rRNA and COI) markers obtained from specimens of nine species. Our results indicate a close relationship between Bairdiella and Odontoscion, and also that the genus Stellifer is not monophyletic, but rather that it consists of two distinct lineages, one clade containing S. microps/S. naso/S. brasiliensis and the other, S. rastrifer/S. stellifer/Stellifer sp. B, which is closer to Ophioscion than the former clade. The O. punctatissimus populations from the northern and southern Brazilian coast were also highly divergent in both nuclear (0.8% for rhodopsin and 0.9% for RAG-1) and mitochondrial sequences (2.2% for 16S rRNA and 7.3% for COI), which we conclude is consistent with the presence of two distinct species. The morphological similarities of the members of the Stellifer group is reinforced by the molecular data from both the present study and previous analyses, which have questioned the taxonomic status of the Stellifer group. If, on the one hand, the group is in fact composed of four genera (Stellifer, Ophioscion, Odontoscion, and Bairdiella), one of the two Stellifer clades should be reclassified as a new genus. However, if the close relationship and the reduced genetic divergence found within the group is confirmed in a more extensive study, including representatives of additional taxa, this, together with the morphological evidence, would support downgrading the whole group to a single genus. Obviously, these contradictory findings reinforce the need for a more systematic taxonomic revision of the Stellifer group as a whole.


Asunto(s)
Núcleo Celular/genética , Mitocondrias/genética , Perciformes/clasificación , Perciformes/genética , Filogenia , Animales , Océano Atlántico , ADN Mitocondrial/genética , Marcadores Genéticos/genética
10.
Mitochondrial DNA ; 25(2): 150-6, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23656293

RESUMEN

We investigated the genetic structure and diversity of M. atricauda, based on 266 specimens collected off the coast of southern Brazil and Argentina at seven locations, covering the whole geographic distribution of this species. A DNA sequence alignment of 904 base pairs of the mitochondrial Control Region revealed a total of 85 haplotypes. F(ST) analyses suggest that M. atricauda does not comprise a single demographic stock. Two different genetic units are identified, which possibly are related to ecological adaptations of the species within its range. Genetic diversity, Bayesian analysis of population structure, and significant negative results for the D and FS tests indicate that M. atricauda populations have undergone recent expansion. The spatial distribution of genetic variation seems to be related to historical colonization from south to north, followed by expansion.


Asunto(s)
ADN Mitocondrial/genética , Genética de Población , Perciformes/genética , Animales , Teorema de Bayes , Variación Genética , Genómica , Geografía , Haplotipos , Océanos y Mares , Análisis de Secuencia de ADN
11.
An Acad Bras Cienc ; 85(4): 1439-47, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24141412

RESUMEN

The tambaqui, Colossoma macropomum, is the most popular fish species used for aquaculture in Brazil but there is no study comparing genetic variation among native and farmed populations of this species. In the present study, we analyzed DNA sequences of the mitochondrial DNA to evaluate the genetic diversity among two wild populations, a fry-producing breeding stock, and a sample of fish farm stocks, all from the region of Santarém, in the west of the Brazilian state of Pará. Similar levels of genetic diversity were found in all the samples and surprisingly the breeding stock showed expressive representation of the genetic diversity registered on wild populations. These results contrast considerably with those of the previous study of farmed stocks in the states of Amapá, Pará, Piauí, and Rondônia, which recorded only two haplotypes, indicating a long history of endogamy in the breeding stocks used to produce fry. The results of the two studies show two distinct scenarios of tambaqui farming in the Amazon basin, which must be better evaluated in order to guarantee the successful expansion of this activity in the region, and the rest of Brazil, given that the tambaqui and its hybrids are now farmed throughout the country.


Asunto(s)
Acuicultura/métodos , Characiformes/genética , ADN Mitocondrial/genética , Variación Genética/genética , Animales , Brasil , Characiformes/clasificación , Genotipo , Haplotipos , Análisis de Secuencia de ADN/veterinaria
12.
Mol Phylogenet Evol ; 66(1): 423-8, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23041386

RESUMEN

Fragments of mitochondrial (COI and rRNA 16S) and nuclear (Tmo-4C4) genes were sequenced to evaluate the phylogenetic relationships among 15 genera of the western South Atlantic Sciaenidae, two freshwater genera and the northwest Pacific Larimichthys crocea. Our results suggest a great diversification for the western Atlantic assemblage; the monophyly of Macrodon, Menticirrhus and Plagioscion genera; the distinctiveness of Bardiella, Stellifer and Ophioscion as belonging to the same clade; the possible existence of two distinct groups in Stellifer; the closer relationship between Lonchurus and Paralonchurus; the non-monophyly of Cynoscion; and the remarkable diversification of Larimus breviceps populations in the Brazilian coast. This is the most comprehensive study evaluating the phylogenetic relationships of the western Atlantic sciaenid and provides a guide for future studies within this family.


Asunto(s)
Evolución Biológica , Perciformes/clasificación , Filogenia , Animales , Océano Atlántico , Teorema de Bayes , Núcleo Celular/genética , ADN Mitocondrial/genética , Funciones de Verosimilitud , Modelos Genéticos , Perciformes/genética , Análisis de Secuencia de ADN
13.
Genet. mol. biol ; 31(1,suppl): 372-376, 2008. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-484613

RESUMEN

Red snappers (Lutjanus purpureus in Brazil and Lutjanus campechanus in USA and Gulf of Mexico) are both under clear effect of overfishing. Because of their high morphological similarity it has already been suggested that they could possibly be considered as a single species. To investigate the degree of similarity and the genetic structure of red snapper populations we constructed a common dataset of partial D-loop mtDNA sequences of L. purpureus from Brazil (Amapá, Pará and Maranhão) and L. campechanus from the Atlantic coast of the USA (Florida, Louisiana and Mississippi). Phylogenetic and population genetic analyses surprisingly depicted high similarity between L. campechanus and L. purpureus, compatible with the hypothesis of a single species of red snapper for the Western Atlantic Ocean. These preliminary but very curious findings open an important discussion regarding the legislation involved on the capture of this overexploited fish resources as well as regarding their taxonomy.


Asunto(s)
Animales , ADN Mitocondrial , Genética de Población , Peces/genética , Filogenia , Peces/clasificación
14.
Genet. mol. biol ; 31(2): 487-492, 2008. graf, tab
Artículo en Inglés | LILACS | ID: lil-484987

RESUMEN

The acoupa weakfish (Cynoscion acoupa - Sciaenidae) is a marine species of croaker with estuarine-dependent behavior, found in the western Atlantic from Panama to Argentina. It is one of the most exploited food fish on the northern coast of Brazil. In this study, DNA sequences were determined from the entire control region (D-loop) of the mitochondrial genome of 297 individuals collected during seven different months between December 2003 and August 2005 on the northern coast of Brazil (Amapá and Pará). Genetic variability expressed by haplotype (h = 0,892) and nucleotide (pi = 0,003) diversities were low compared to other heavily exploited marine fish species from the western Atlantic and eastern Asia. AMOVA depicted a lack of genetic structuring among the samples from different years, indicating the presence of a single stock of C. acoupa within the sample area. The possible reasons for the low levels of genetic diversity are discussed. These results demonstrate a need for the monitoring of C. acoupa harvesting and the preservation of the estuaries within its geographic range, considering that this large fish depends on estuarine ecosystems during part of its life cycle.

15.
Mol Ecol ; 15(14): 4361-73, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17107470

RESUMEN

Phylogeographic patterns in Macrodon ancylodon sampled from 12 locations across all its range were investigated using mitochondrial DNA cytochrome b sequences, and analysed together with patterns of morphometric differentiation. Populations of the North Brazil and the Brazil currents, with warmer waters, form a clade (tropical clade) separated by 23 fixed mutations from the populations that inhabit regions of colder waters influenced by the Brazil and Malvinas currents (subtropical clade). No gene flow exists between the tropical and subtropical clades, and most likely also between the two groups of the tropical clade. Distribution of these clades and groups is correlated with flow of currents and their temperatures, and is facilitated by larval retention and low adult migration. Despite differentiation at the molecular level, fishes analysed from all these current-influenced regions are morphometrically homogeneous. Throughout its range M. ancylodon inhabits the same, or very similar niche; thus, stabilizing selection probably promotes the retention of highly conserved morphology despite deep genetic divergence at the mitochondrial DNA cytochrome b.


Asunto(s)
Variación Genética , Perciformes/anatomía & histología , Perciformes/genética , Animales , Océano Atlántico , Secuencia de Bases , Demografía , Genética de Población , Geografía , Funciones de Verosimilitud , Filogenia , América del Sur
16.
Genet. mol. biol ; 26(2): 151-161, Jun. 2003. ilus, mapas, tab
Artículo en Inglés | LILACS | ID: lil-345965

RESUMEN

The king weakfish (pescada-gó in Portuguese - Macrodon ancylodon (Sciaenidae), a demersal (bottom-feeding) species found in South America Atlantic coastal waters from the Gulf of Paria in Venezuela to Baia Blanca in Argentina, is an economically important species because of its abundance and wide acceptance by consumers. Because of its wide distribution this fish may be subject to geographic isolation and this may have resulted in distinct populations along its coastal range. Considering that this species represents an important economic resource, confirmation of whether M. ancylodon is a single species or there are different genetic stocks spread over its wide distribution would be an important contribution to conservation policies and population management of the king weakfish. To investigate differences between king weakfish populations we used the cytochrome b and 16S rRNA genes to characterize M. ancylodon specimens caught throughout its South American range from Venezuela to Argentina. Our results clearly distinguished two genetically different groups which show nucleotide divergence and genetic structuring patterns that strongly suggest they may be different species, disagreeing with the widely accepted traditional taxonomy that accepts only one species of Macrodon in the western Atlantic


Asunto(s)
Animales , ADN Mitocondrial , Peces , Variación Genética , ARN Ribosómico , Citocromos b
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