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1.
Braz J Biol ; 84: e274862, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511772

RESUMO

Sharks of the genus Sphyrna are under intense exploitation globally. In Brazil's northern coast, this genus represents a high proportion of fisheries landings and comprises four species. However, due to difficulty of specific identification when specimens are landed, most of the records are limited to the genus level. Here we analyzed the effectiveness of ITS2 (Internal Transcribed Spacer 2 of rDNA) fragment length protocol (Abercrombie et al., 2005) for identifying hammerhead shark species, comparing with the analysis of COI (Cytochrome oxidase subunit I) and ITS2 sequences. We evaluated samples of muscle tissue acquired in the main fishing ports of Maranhão: Carutapera, Raposa e Tutóia. Sampling was conducted between March 2017 to March 2018 and complemented with material deposited in collection (2015). COI results indicated the occurrence of endangered species which are prohibited to be landed. These include Sphyrna mokarran (67%), S. lewini (15%), S. tudes (3%), and S. tiburo (15%). For the ITS2 marker, we investigated the optimization of the protocol developed by Abercrombie (2005) for to improve the use in this geographical area througout design of a new primers.


Assuntos
Tubarões , Animais , Tubarões/genética , Brasil , Espécies em Perigo de Extinção , Pesqueiros , Alimentos Marinhos
5.
R Soc Open Sci ; 8(7): 210850, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34350022

RESUMO

The Roman Empire shaped western civilization, and many Roman principles are embodied in modern institutions. Although its political institutions proved both resilient and adaptable, allowing it to incorporate diverse populations, the Empire suffered from many conflicts. Indeed, most emperors died violently, from assassination, suicide or in battle. These conflicts produced patterns in the length of time that can be identified by statistical analysis. In this paper, we study the underlying patterns associated with the reign of the Roman emperors by using statistical tools of survival data analysis. We consider all the 175 Roman emperors and propose a new power-law model with change points to predict the time-to-violent-death of the Roman emperors. This model encompasses data in the presence of censoring and long-term survivors, providing more accurate predictions than previous models. Our results show that power-law distributions can also occur in survival data, as verified in other data types from natural and artificial systems, reinforcing the ubiquity of power-law distributions. The generality of our approach paves the way to further related investigations not only in other ancient civilizations but also in applications in engineering and medicine.

9.
Arq. bras. med. vet. zootec. (Online) ; 69(6): 1565-1572, nov.-dez. 2017. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-910569

RESUMO

This study aimed to evaluate aspects of host immune response using an experimental infection model of Corynebacterium pseudotuberculosis (CP) in C57/Black6 wild-type and knockout for nitric oxide (KO-NO) mice. 28 mice were evaluated: 4 wild-type controls; 10 wild-type infected with CP; 4 KO-NO controls; 10 KO-NO infected with CP. Infection procedures were carried out by intraperitoneal inoculation using 107. Infected C57/Black6 KO-NO mice began to die after the 5° day post-inoculation, up until the 14º day. Neutrophils were found in increased numbers in the infiltrate of KO-NO murine peritoneal cavities. Examination of splenic tissue revealed an accumulation of lymphocytes, predominantly CD8 T-cells, in experimental animal groups. KO-NO animals were found to have a predominance of granulomas 7 days post-inoculation, primarily in the lymph nodes. In addition, greater amounts of bacteria were recovered from the mesenteric lymph nodes of KO-NO mice. There was no statistically significant difference in the levels of total IgG and its subclasses 14 days post-inoculation between KO-NO and wild groups. The results suggest the importance of nitric oxide in the process of controlling CP infection, as KO-NO animals were observed to be markedly more affected by infection with this bacterium.(AU)


O objetivo deste estudo foi avaliar os aspectos da resposta imune do hospedeiro, mediante o uso de um modelo experimental de infecção de Corynebacterium pseudotuberculosis (CP) em camundongos C57/Black6 do tipo selvagem e em C57/Black6 knockout para o óxido nítrico (KO-NO). Foram avaliados 28 camundongos: quatro controles de tipo selvagem; 10 do tipo selvagem infectados com CP; quatro controles KO-NO; e 10 KO-NO infectados com CP. A infecção foi realizada via intraperitoneal, usando-se 107. Os animais C57/Black6 KO-NO infectados começaram a vir a óbito no quinto dia pós-inoculação, o que aconteceu até o 14º dia. Um número maior de neutrófilos foi encontrado na sua cavidade peritoneal. O exame do baço revelou um acúmulo de linfócitos, predominantemente células T CD8, nos grupos de animais experimentais. Nos animais KO-NO, foi observada a presença de granulomas, sete dias pós-inoculação, principalmente nos gânglios linfáticos. Além disso, uma maior quantidade de bactérias foi detectada dos linfonodos mesentéricos desses animais. Não houve diferença estatisticamente significante nos níveis séricos IgG total e em suas subclasses aos 14 dias pós-inoculação nos grupos KO-NO e selvagem. Os resultados obtidos sugerem a importância do óxido nítrico no processo de controle da infecção por CP.(AU)


Assuntos
Animais , Camundongos , Corynebacterium pseudotuberculosis/imunologia , Linfadenite/prevenção & controle , Camundongos Knockout/imunologia , Óxido Nítrico/uso terapêutico , Linfadenite/veterinária
10.
Rev Sci Tech ; 36(3): 965-970, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30160687

RESUMO

Equatorial Guinea (EG) is a country in Central Africa with typical tropical weather. Sheep are an important source of food in EG, but the absence of information regarding infectious diseases that affect the native flocks of small ruminants is a concern. The country is currently implementing several new practices in the sheep industry associated with the importation of sheep from other countries. This study aimed to evaluate the seroprevalence of bacterial infections that are important to the sheep industry in EG sheep flocks. The detection of specific antibodies for the four agents studied was performed using enzyme-linked immunosorbent assay in 1,002 serum samples from EG sheep. The results showed a true prevalence of 13.37% for antibodies against Corynebacterium pseudotuberculosis, 0.59% for Brucella ovis, 19.89% for Chlamydophila abortus and 0.79% for Mycoplasma agalactiae in animals from production flocks. Among a group of 35 samples from isolated native animals, 47.56% were seropositive for antibodies against C. pseudotuberculosis, 42.84% for B. ovis, 54.28% for C. abortus and 11.35% for M. agalactiae. These results comprise the first report of the prevalence of infectious diseases in sheep in EG. They highlight the importance of adopting adequate measures to prevent infection by bacteria endemic to EG native flocks during the development of the sheep industry in the country.


La Guinée équatoriale est un pays d'Afrique centrale au climat typiquement tropical. Les moutons constituent une source importante d'aliments pour le pays, ce qui rend particulièrement alarmante l'absence d'informations concernant les maladies infectieuses affectant le cheptel autochtone de petits ruminants. Le pays met actuellement en place de nouvelles pratiques d'élevage ovin, en lien avec l'importation de moutons d'autres pays. La présente étude avait pour objet d'évaluer la prévalence sérologique de quelques infections bactériennes majeures pour le secteur de l'élevage dans le cheptel ovin de la Guinée équatoriale. Pour les besoins de l'étude, 1 002 échantillons de sérum prélevés de moutons autochtones ont été soumis à une épreuve immuno-enzymatique pour la détection d'anticorps spécifiques dirigés contre quatre agents bactériens. La prévalence réelle de moutons issus de troupeaux d'élevage possédant des anticorps vis-à-vis de chacune des bactéries recherchées s'est élevée à 13,37 % pour Corynebacterium pseudotuberculosis, à 0,59 % pour Brucella ovis, à 19,89 % pour Chlamydophila abortus et à 0,79 % pour Mycoplasma agalactiae. Dans un groupe de 35 prélèvements issus d'animaux isolés autochtones, le taux d'échantillons positifs était de 47,56 % pour C. pseudotuberculosis, de 42,84 % pour B. ovis, de 54,28 % pour C. abortus et de 11,35 % pour M. agalactiae. Ces résultats constituent le premier rapport sur la prévalence des maladies infectieuses chez le mouton en Guinée équatoriale. Ils soulignent l'importance d'adopter des mesures appropriées afin de prévenir les infections dues à des bactéries endémiques dans le cheptel autochtone de la Guinée équatoriale, à un moment où ce pays cherche à développer l'élevage ovin.


Guinea Ecuatorial es un país centroafricano con un clima tropical típico, en el que las ovejas constituyen una importante fuente de alimento. Por ello es preocupante la ausencia de información sobre las enfermedades infecciosas que afectan a los rebaños autóctonos de pequeños rumiantes. El país está implantando ahora una serie de nuevos procedimientos en el sector ovino, vinculados a la importación de ovejas de otros países. Los autores describen un estudio encaminado a evaluar la seroprevalencia en los rebaños de ovejas del país de infecciones bacterianas de importancia para el sector. Para detectar anticuerpos específicos contra los cuatro agentes estudiados se aplicó la técnica del ensayo inmunoenzimático a 1 002 muestras de suero de ovejas autóctonas. Los resultados pusieron de manifiesto una prevalencia real de anticuerpos contra Corynebacterium pseudotuberculosis del 13,37%, del 0,59% contra Brucella ovis, del 19,89% contra Chlamydophila abortus y del 0,79% contra Mycoplasma agalactiae en ejemplares pertenecientes a rebaños productivos. De un grupo de 35 muestras procedentes de animales autóctonos aislados, un 47,56% resultaron seropositivas para los anticuerpos contra C. pseudotuberculosis, un 42,84% en el caso de B. ovis, un 54,28% en el de C. abortus y un 11,35% en el de M. agalactiae. Estos resultados, que constituyen el primer informe sobre la prevalencia de enfermedades infecciosas en las ovejas de Guinea Ecuatorial, demuestran la importancia de instituir medidas adecuadas para prevenir la infección por bacterias endémicas de los rebaños autóctonos de Guinea Ecuatorial en un momento en que la industria ovina del país está en pleno crecimiento.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças dos Ovinos/microbiologia , Animais , Ensaio de Imunoadsorção Enzimática/veterinária , Guiné Equatorial/epidemiologia , Feminino , Estudos Soroepidemiológicos , Ovinos , Doenças dos Ovinos/imunologia
11.
J Fish Biol ; 88(3): 1204-14, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26822755

RESUMO

Monophyly of the genus Leporinus (Characiformes: Anostomidae) was tested by sequencing and analysing a total of 4732 bp, including two mitochondrial [cytochrome oxidase subunit 1 (CO1) and cytochrome b (Cytb)] and three nuclear [myosin heavy chain 6 cardiac muscle alpha (Myh6), recombination activating gene 1 (RAG1) and recombination activating gene 2 (RAG2)] loci for 22 species of Leporinus, or c. 25% of all described species in the genus. Phylogenetic tree analyses (maximum parsimony, maximum likelihood and Bayesian species tree) indicate Leporinus to be paraphyletic, with monophyly being rejected by both Kishino-Hasegawa and Shimodaira-Hasegawa tests. The sequenced species of Leporinus are distributed across five clades that are interleaved among other anostomid genera. Several taxonomic changes are suggested as being necessary to restore monophyly for the group. The clade containing the type species, Leporinus fasciatus, should be considered Leporinus sensu stricto and at least three new genera should be described for other species currently considered part of Leporinus.


Assuntos
Caraciformes/classificação , Caraciformes/genética , Genes Mitocondriais , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , Citocromos b/genética , DNA/química , DNA/isolamento & purificação , Proteínas de Ligação a DNA/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Água Doce , Marcadores Genéticos , Proteínas de Homeodomínio/genética , Funções Verossimilhança , Cadeias Pesadas de Miosina/genética , Alinhamento de Sequência/veterinária , Análise de Sequência de DNA/veterinária
12.
Arq. bras. med. vet. zootec ; 67(6): 1751-1755, nov.-dez. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-768141

RESUMO

A epididimite infecciosa ovina é uma das principais enfermidades reprodutivas de carneiros. O presente estudo teve por objetivo desenvolver protocolos de PCR em tempo real para B. ovis e H. somni e avaliar sua aplicabilidade em amostras de sêmen e urina de carneiros. Delinearam-se primers e sondas espécie-específicos para cada agente. As sondas foram delineadas com o sistema TaqMan incorporando um marcador FAM para B. ovis e Cy5 para H. somni na extremidade 5' e um quencher na extremidade 3'. A PCR em tempo real para B. ovis e H. somni foi altamente sensível, uma vez que a amplificação de DNA ocorreu com até 0,2ng de DNA/reação. A especificidade dos iniciadores e sondas foi avaliada com amostras de DNA de outros agentes causadores de epididimite ovina e nenhuma amplificação inespecífica foi observada. A aplicabilidade da técnica em amostras biológicas também foi confirmada, pois não houve perda de eficácia (P>0,05) quando comparada à PCR convencional com amostras de sêmen e urina de carneiros experimentalmente infectados.


Assuntos
Animais , Brucella ovis/isolamento & purificação , Epididimite/diagnóstico , Ovinos/microbiologia , Pasteurellaceae/isolamento & purificação , Sêmen/microbiologia , Urina/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária
13.
Dentomaxillofac Radiol ; 43(2): 20130238, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24319125

RESUMO

OBJECTIVES: In the present study, we developed new software for quantitative analysis of cervical vertebrae maturation, and we evaluated its applicability through a multinomial logistic regression model (MLRM). METHODS: Digitized images of the bodies of the second (C2), third (C3) and fourth (C4) cervical vertebrae were analysed in cephalometric radiographs of 236 subjects (116 boys and 120 girls) by using a software developed for digitized vertebrae analysis. The sample was initially distributed into 11 categories according to the Fishman's skeletal maturity indicators and were then grouped into four stages for quantitative cervical maturational changes (QCMC) analysis (QCMC I, II, III and IV). Seven variables of interest were measured and analysed to identify morphologic alterations of the vertebral bodies in each QCMC category. RESULTS: Statistically significant differences (p < 0.05) were observed among all QCMC categories for the variables analysed. The MLRM used to calculate the probability that an individual belonged to each of the four cervical vertebrae maturation categories was constructed by taking into account gender, chronological age and four variables determined by digitized vertebrae analysis (Ang_C3, MP_C3, MP_C4 and SP_C4). The MLRM presented a predictability of 81.4%. The weighted κ test showed almost perfect agreement (κ = 0.832) between the categories defined initially by the method of Fishman and those allocated by the MLRM. CONCLUSIONS: Significant alterations in the morphologies of the C2, C3 and C4 vertebral bodies that were analysed through the digitized vertebrae analysis software occur during the different stages of skeletal maturation. The model that combines the four parameters measured on the vertebral bodies, the age and the gender showed an excellent prediction.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Vértebras Cervicais/crescimento & desenvolvimento , Software , Determinação da Idade pelo Esqueleto/estatística & dados numéricos , Fatores Etários , Envelhecimento/fisiologia , Ossos do Carpo/diagnóstico por imagem , Cefalometria/métodos , Vértebras Cervicais/diagnóstico por imagem , Criança , Estudos Transversais , Feminino , Previsões , Ossos da Mão/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Modelos Logísticos , Masculino , Projetos Piloto , Radiografia Dentária Digital/métodos , Fatores Sexuais
14.
Arq. bras. med. vet. zootec ; 65(1): 55-60, fev. 2013. graf, tab
Artigo em Inglês | LILACS | ID: lil-667536

RESUMO

The aim of the present study was to evaluate a species-specific nested PCR based on a previously described species-specific PCR for detection of B. ovis in semen and urine samples of experimentally infected rams. The performance of the species-specific nested PCR was compared with the results of a genus-specific PCR. Fourteen rams were experimentally infected with the Brucella ovis REO 198 strain and samples of semen and urine were collected every week up to 180 days post infection. Out of 83 semen samples collected, 42 (50.6%) were positive for the species-specific nested PCR, and 23 (27.7%) were positive for the genus-specific PCR. Out of 75 urine samples, 49 (65.3%) were positive for the species-specific nested PCR, whereas 11 (14.6%) were genus-specific PCR positive. Species-specific nested PCR was significantly more sensitive (P<0.001) than the genus-specific PCR in semen and urine from experimentally infected rams. In conclusion, the species-specific nested PCR developed in this study may be used as a diagnostic tool for the detection of B. ovis in semen and urine samples from suspected rams.


O presente estudo objetivou avaliar uma técnica de nested PCR espécie-específica delineada a partir de PCR espécie-específica descrita anteriormente para detecção de B. ovis em sêmen e urina de carneiros infectados experimentalmente. O desempenho da nested PCR espécie-específica foi comparado com os resultados de uma PCR gênero-específica. Quatorze carneiros foram infectados experimentalmente com Brucella ovis REO 198 e amostras de sêmen e de urina foram colhidas semanalmente até 180 dias após a infecção. De 83 amostras de sêmen, 42 (50,6%) foram positivas pela nested PCR espécie-específica, e 23 (27,7%) foram positivas pela PCR gênero-específica. De 75 amostras de urina, 49 (65,3%) foram positivas pela nested PCR espécie-específica, enquanto 11 (14,6%) foram positivas em PCR gênero-específica. A técnica de nested PCR espécie-específica foi significativamente mais sensível (P<0,001) do que a PCR gênero-específica no sêmen e na urina de carneiros infectados experimentalmente. Em conclusão, a nested PCR espécie-específica desenvolvida neste estudo pode ser utilizada como ferramenta de diagnóstico para detecção de B. ovis em sêmen e urina de carneiros suspeitos.


Assuntos
Animais , Análise do Sêmen/veterinária , Brucella ovis/patogenicidade , Brucella ovis/química , Reação em Cadeia da Polimerase/veterinária
15.
Acta Psychiatr Scand ; 127(2): 153-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22943487

RESUMO

OBJECTIVE: To evaluate the efficacy of psychoeducation in the symptomatic and functional recovery, and quality of life (QoL) in a sample of patients with bipolar disorder (BD). METHOD: The sample comprised 55 patients with BD I and II in remission (Young Mania Rating Scale ≤6 and Hamilton Depression Rating Scale ≤7). Out-patients were matched assigned to receive 16 sessions of psychoeducation [experimental group (EG)] or 16 sessions of placebo without psychoeducation [control group (CG)]. Groups were evaluated at study baseline, midpoint, endpoint, and at 6- and 12-month follow-ups. RESULTS: No significant differences between the groups were found for the variables evaluated (mood symptoms, functioning and QoL), except for overall clinical improvement, subjectively perceived by EG subjects. Both groups showed a trend toward improved clinical global impression and QoL (environmental). No reduction in mood symptoms or improvement in psychosocial functioning was observed. Psychosocial treatment compliance was positively correlated with global functioning, social adjustment, sociability, and global clinical impression. CONCLUSION: Sixteen session psychoeducation seems to be ineffective to prevent mood episodes or improve functioning in a sample of bipolar patients.


Assuntos
Transtorno Bipolar/terapia , Educação de Pacientes como Assunto , Adolescente , Adulto , Idoso , Transtorno Bipolar/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente/psicologia , Educação de Pacientes como Assunto/métodos , Escalas de Graduação Psiquiátrica , Psicoterapia , Qualidade de Vida/psicologia , Resultado do Tratamento , Adulto Jovem
16.
J Periodontal Res ; 47(1): 27-32, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21848614

RESUMO

BACKGROUND AND OBJECTIVE: Porphyromonas gingivalis, an anaerobic gram-negative bacterium, is associated with chronic periodontitis. This study was undertaken to evaluate the production of interleukin (IL)-1ß, IL-8 and IL-10 by human peripheral blood mononuclear cells (PBMC) stimulated with P. gingivalis antigens and to assess the levels of serum immunoglobulin (Ig)G, IgA and IgG subclasses raised against P. gingivalis HmuY protein. MATERIAL AND METHODS: PBMC from patients with chronic periodontitis (CP) and from nonperiodontitis (NP) control subjects were stimulated with P. gingivalis antigens, and the cytokine levels in the culture supernatants were determined by ELISA. The specificity of serum antibodies raised against HmuY was analyzed by Western blotting and by ELISA. RESULTS: Compared with the NP controls, the CP patients produced higher levels of total serum IgG and IgG1 specific for P. gingivalis HmuY. No differences were found between CP and NP groups in the production of IL-1ß and IL-8 by PBMC stimulated with total P. gingivalis antigens. Only P. gingivalis lipopolysaccharide (LPS) induced higher levels of IL-10 in the CP group. Higher levels of IL-1ß and IL-10 were induced by HmuY than by other antigens derived from the wild-type P. gingivalis strains. In contrast, total antigens derived from the hmuY-deletion mutant strain induced the production of significantly higher levels of IL-8 and significantly lower levels of IL-1ß. CONCLUSION: Our data suggest that P. gingivalis HmuY may be considered an immunogenic protein associated with host-pathogen interactions.


Assuntos
Proteínas de Bactérias/imunologia , Proteínas de Transporte/imunologia , Hemeproteínas/imunologia , Imunoglobulina G/imunologia , Interleucina-10/imunologia , Interleucina-1beta/imunologia , Interleucina-8/imunologia , Porphyromonas gingivalis/imunologia , Adulto , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/genética , Western Blotting , Proteínas de Transporte/genética , Periodontite Crônica/sangue , Periodontite Crônica/imunologia , Eletroforese em Gel de Poliacrilamida , Feminino , Deleção de Genes , Proteínas Ligantes de Grupo Heme , Hemeproteínas/genética , Humanos , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Leucócitos Mononucleares/imunologia , Lipopolissacarídeos/imunologia , Masculino , Porphyromonas gingivalis/genética
17.
J Med Virol ; 83(10): 1826-33, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21837801

RESUMO

Respiratory syncytial virus (RSV) is a major cause of acute respiratory disease in infants and young children. Considering that several aspects of the humoral immune response to RSV infection remain unclear, this study aimed to investigate the occurrence, levels, and avidity of total IgG, IgG1, and IgG3 antibodies against RSV in serum samples from children ≤5 years old. In addition, a possible association between antibody avidity and severity of illness was examined. The occurrence and levels of RSV-specific IgG depended on age, with infants <3 months old displaying high levels of antibodies, which were probably acquired from the mother. Children ≥24 months old also showed frequent occurrence and high levels of IgG, which was produced actively during infection. In addition, the avidity assay showed that the avidity of RSV-specific total IgG and IgG1 was lower in infants <3 months old who had acute respiratory disease than in age-matched controls. The avidity of RSV-specific IgG detected in children ≥24 months old with lower respiratory infection was lower than that in children with upper respiratory infection. These results indicate that the presence of high avidity RSV-specific IgG antibodies may lead to better protection against RSV infection in children <3 months old, who may have a lower probability of developing disease of increased severity. In addition, children ≥24 months old with RSV-specific IgG antibodies of low avidity tended to develop more severe RSV illness. These findings may be helpful in establishing vaccination schedules when a vaccine becomes available.


Assuntos
Anticorpos Antivirais/imunologia , Afinidade de Anticorpos , Imunoglobulina G/imunologia , Infecções por Vírus Respiratório Sincicial/imunologia , Vírus Sinciciais Respiratórios/imunologia , Infecções Respiratórias/imunologia , Anticorpos Antivirais/sangue , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/classificação , Lactente , Masculino , Infecções Respiratórias/virologia , Índice de Gravidade de Doença
18.
Mol Phylogenet Evol ; 59(1): 177-94, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21315164

RESUMO

Pseudoplatystoma is a commercially important genus of Neotropical migratory catfishes widely distributed in all major river basins of South America. Historically, only three species were recognized, but a recent revision proposed eight putative morphospecies for the genus. A molecular study based on mitochondria DNA (mtDNA) provided support for recognition of only some of the species and raised questions about species boundaries in this group. We present a more encompassing analysis based on mtDNA (cytochrome b, 818bp) and nuclear DNA-based phylogenies (Rag1 intron 1, 664bp and S7 intron 1, 635bp) for a more extensive sampling (279 individuals from 42 localities) of all putative species in all major river basins. Patterns generated by individual gene genealogies and a multispecies coalescent analysis provided evidence to suggest recognition of only four distinct species in this genus: Pseudoplatystoma magdaleniatum, Pseudoplatystoma corruscans, Pseudoplatystoma tigrimun (sensu lato) and Pseudoplatystoma fasciatum (sensu lato). The species phylogeny places P. magdaleniatum as the sister group to all the other species in the genus, but the relationships among P. fasciatum s.l, P. tigrimum s.l., and P. corruscans could not be resolved with confidence.


Assuntos
Peixes-Gato/genética , Mitocôndrias/genética , Filogenia , Animais , Teorema de Bayes , Peixes-Gato/classificação , Citocromos b/genética , Genes RAG-1 , Marcadores Genéticos , Haplótipos , Íntrons , Funções Verossimilhança , Tipagem de Sequências Multilocus , Rios , América do Sul , Clima Tropical
19.
J. venom. anim. toxins incl. trop. dis ; 16(4): 654-658, 2010. tab
Artigo em Inglês | LILACS | ID: lil-566166

RESUMO

The aim of the current study was to evaluate the infection rate by Brucella spp. in wild and in captive animals. Serum samples from 121 animals (94 free-ranging and 27 captive) of different mammal species were evaluated. Sera were submitted to rose Bengal test (RBT) for screening and serum agglutination tests (SAT) and 2-mercaptoethanol test (2-ME) for confirmatory results. Nine animals (five free-ranging and four captive) tested positive in RBT, but negative in the confirmatory tests. Several domestic animal diseases that have control programs are not focused on wild reservoirs, such as brucellosis in Brazil. The study of new reservoirs in wildlife is essential to prevent emerging diseases.


Assuntos
Animais , Animais Selvagens/virologia , Brucelose , Brucelose/transmissão
20.
Braz. j. biol ; 68(4,supl): 1039-1050, Nov. 2008.
Artigo em Inglês | LILACS | ID: lil-504456

RESUMO

Human activities have a considerable impact on hydrographic systems and fish fauna. The present review on conservation genetics of neotropical freshwater fish reveals that DNA analyses have been promoting increased knowledge on the genetic structure of fish species and their response to environmental changes. This knowledge is fundamental to the management of wild fish populations and the establishment of Evolutionary Significant Units capable of conserving genetic integrity. While population structuring can occur even in long-distance migratory fish, isolated populations can show reduced genetic variation and be at greater risk of extinction. Phylogeography and phylogeny have been powerful tools in understanding the evolution of fish populations, species and communities in distinct neotropic environments. Captive fish can be used to introduce new individuals and genes into the wild and their benefits and disadvantages can be monitored through genetic analysis. Understanding how fish biodiversity in neotropical freshwaters is generated and maintained is highly important, as these habitats are transformed by human development and fish communities are increasingly exploited as food sources to sustain a growing human population.


Atividades humanas têm um grande impacto sobre os sistemas hidrográficos e a fauna de peixes. A presente revisão em genética da conservação dos peixes de água doce neotropicais revela que as análises de DNA têm promovido um crescimento no conhecimento da estrutura genética das espécies e suas respostas às alterações ambientais. Este conhecimento é fundamental para o manejo das populações de peixes nativos e para o estabelecimento de Unidades Evolutivas Significantes capazes de conservar a integridade genética dessas populações. Enquanto o fenômeno de estruturação de populações pode ocorrer mesmo em peixes migradores de longas distâncias, populações isoladas podem mostrar reduzida variação genética e apresentar grande risco de extinção. Em adição, a filogeografia e a filogenia têm dado importantes contribuições para o entendimento da evolução das populações, espécies e comunidades de peixes em distintos ambientes neotropicais. Populações de cativeiro podem ser utilizadas como fonte de introdução de novos indivíduos e genes no ambiente natural e seus benefícios e desvantagens podem ser monitorados por meio de análises genéticas. É altamente importante, portanto, entender como é gerada e mantida a biodiversidade de peixes de água doce neotropicais, uma vez que os habitats são transformados pelo desenvolvimento humano e as comunidades de peixes têm sido intensamente exploradas como alimento de sustentação desse crescimento das populações humanas.


Assuntos
Animais , Humanos , Biodiversidade , Conservação dos Recursos Naturais , Água Doce , Peixes/genética , Biologia Molecular , Clima Tropical , DNA , Peixes/classificação , Marcadores Genéticos , Variação Genética , Filogenia , Densidade Demográfica
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