RESUMEN
Abstract Escherichia coli O157:H7 is a foodborne pathogen implicated in numerous outbreaks worldwide that has the ability to cause extra-intestinal complications in humans. The Enteropathogens Division of the Central Public Health Laboratory (CPHL) in Paraguay is working to improve the genomic characterization of Shiga toxin-producing E. coli (STEC) to enhance laboratory-based surveillance and investigation of foodborne disease outbreaks. Whole genome sequencing (WGS) is proposed worldwide to be used in the routine laboratory as a high-resolution tool that allows to have all the results in a single workflow. This study aimed to carry out for the first time, the genomic characterization by WGS of nine STEC O157:H7 strains isolated from human samples in Paraguay. We were able to identify virulence and resistance mechanisms, MLST subtype, and even establish the phylogenetic relationships between isolates. Furthermore, we detected the presence of strains belonging to hypervirulent clade 8 in most of the isolates studied.
Resumen Escherichia coli O157:H7 es un patógeno transmitido por alimentos implicado en numerosos brotes en todo el mundo y es capaz de causar complicaciones extraintestinales en humanos. La sección de «Enteropatógenos¼ del Laboratorio Central de Salud Pública trabaja en mejorar la caracterización genómica de STEC, de modo de potenciar la vigilancia laboratorial y la investigación de brotes de enfermedades transmitidas por alimentos. La secuenciación de genoma completo (WGS, por sus siglas en inglés) se propone a nivel mundial como una herramienta de alta resolución para ser utilizada en el laboratorio de rutina, ya que permite obtener todos los resultados en un único proceso. El objetivo de este trabajo fue llevar a cabo, por primera vez, la caracterización genómica por WGS de nueve cepas STEC O157:H7 aisladas en Paraguay a partir de muestras de origen humano. Pudimos identificar los factores de virulencia, los mecanismos de resistencia, el subtipo MLST, e incluso pudimos establecer la relación filogenética entre los aislamientos. Además, detectamos que la mayoría de las cepas pertenecían al clado hipervirulento 8.
RESUMEN
@#Highly Pathogenic Avian Influenza (HPAI) is a highly contagious disease in poultry. The outbreaks can lead to flock mortality up to 100% in two to three days. In July 2018, high mortality in a commercial layer farm in Kauluan village, Sabah was reported. Samples were sent to Veterinary Research Institute Ipoh for diagnosis. Virus isolation and molecular detection is carried out simultaneously. The causative agent was then identified as AI H5N1 virus by real time reverse transcription-polymerase chain reaction (RT-PCR). The virus was then subjected for further nucleotide sequencing of full length hemagglutinin (HA) and neuraminidase (NA) gene. The PQRERRRKR/GLF motif at the HA cleavage site indicated that the isolate was of HPAI virus. Phylogenetic analysis of the HA gene showed that the isolate was belonged to the clade 2.3.2.1c virus. In the HA gene, besides the S133A substitution, the virus possesses conserved amino acid at most of the avian receptor binding sites including the glutamine (Q) and glycine (G) at position 222 and 224 respectively, indicating that the virus retains the avian-type receptor binding preference. As such, the zoonotic potential of the virus was relatively low. On the other hand, though the N154D and T156A substitution were detected in the same gene, the pandemic potential of this Sabah 2.3.2.1c virus is low in the absence of the Q222L, G224S, H103Y, N220K and T315I. A typical 20 amino acid deletion with loss of four corresponding glycosylation sites in the NA stalk region was visible. Though three NA resistance markers were detected, the virus was predicted to be sensitive to NA inhibitor. This is the first HPAI H5N1 outbreak in Sabah. The introduction of this virus into East Malaysia for the first time raised an alert alarm of the future epidemic potential. Strict farm biosecurity, continuous surveillance programme in poultry, wild birds, migratory birds; molecular epidemiology as well as risk assessment for the virus with pandemic potential are needed in dealing with emergence of new influenza virus in the country.
RESUMEN
ABSTRACT Monkeypox virus (MPXV), a zoonotic virus endemic to the African continent, has been reported in 33 non-endemic countries since May 2022. We report an almost complete genome of the first confirmed case of MPXV in Brazil. Shotgun metagenomic sequencing was completed in 18 hours, from DNA extraction to consensus sequence generation.
RESUMEN
Although the number of recently described Tovomita species is relatively high, much more remains to be done, given that each new survey of representative Amazonian collections reveals many potentially undescribed taxa. In the treatment for Tovomita published in Flora of the Venezuelan Guayana, at least six distinct morphotypes did not match any previously described species. Here we recognize morphotype "D" as a new endemic species from Cerro de la Neblina. Additionally, we provide an identification key to the Tovomita species in Venezuela. (AU)
Asunto(s)
Ecosistema Amazónico , Clusiaceae , VenezuelaRESUMEN
Abstract: Leguminosae includes six subfamilies, where the traditionally recognised subfamily Mimosoideae was accepted as a distinct clade included within the recircumscribed subfamily Caesalpinioideae, called informally as Mimosoid clade. The representatives of the tribes Acacieae and Ingeae can be differentiated principally in terms of the patterns of their stamens, being free in Acacieae and monadelphous in Ingeae. The floristic survey of Acacieae and Ingeae in the Environmental Protection Area Serra Branca included analysis of specimens collected from June 2011 to September 2012. The analyses were supplemented with dried collections from the following herbaria: ALCB, HRB and HUEFS. Ten species were cataloged, distributed among four genera of Ingeae: Calliandra Benth. (1 sp.), Chloroleucon (Benth.) Britton & Rose ex Record (1 sp.), Enterolobium Mart. (1 sp.), Pithecellobium Mart. (1 sp.); and one genus of Acacieae: Senegalia Raf. (6 spp.). The most representative species were Calliandra aeschynomenoides Benth. associated with sandy and stony soils and Chloroleucon foliolosum (Benth.) G.P.Lewis and Senegalia bahiensis (Benth.) Seigler & Ebinger growing on sandy-clay soils. The taxonomic treatment includes a key for the identification, descriptions, illustrations, photos, data of the geographical distribution phenological data and comments about the species.
Resumo: Leguminosae inclui seis subfamílias, onde a tradicional subfamília Mimosoideae foi reconhecida como um clado distinto dentro da recircunscrita subfamília Caesalpinioideae, chamado de clado Mimosoida. Os representantes das tribos Acacieae e Ingeae podem ser diferenciadas principalmente pelo padrão dos estames, sendo livres em Acacieae e monoadelfos em Ingeae. O levantamento florístico de Acacieae e Ingeae na Área de Proteção Ambiental Serra Branca compreendeu análises de espécimes coletados no período de junho 2011 a setembro 2012. As análises foram complementadas com coleções herborizadas depositadas nos seguintes herbários: ALCB, HRB e HUEFS. Foram catalogadas dez espécies, distribuídas em quatro gêneros de Ingeae: Calliandra Benth. (1 sp.); Chloroleucon (Benth.) Britton & Rose ex Record (1 sp.); Enterolobium Mart. (1 sp.) e Pithecellobium Mart. (1 sp.), e um gênero de Acaciae: Senegalia Raf. (6 spp.). As espécies mais representativas foram Calliandra aeschynomenoides Benth. associada a solos arenoso-pedregosos e Chloroleucon foliolosum (Benth.) G.P.Lewis e Senegalia bahiensis (Benth.) Seigler & Ebinger a solos arenoso-argilosos. O tratamento taxonômico inclui uma chave de identificação, descrições, ilustrações, fotos, dados de distribuição geográfica, dados fenológicos e comentários sobre as espécies.
RESUMEN
SUMMARY The genus Brucella is a globally distributed intracellular pathogen that affects animals and humans and presents low genetic variability, which is a challenge for its phylogenetic reconstruction. Genus differentiation originally occurred due to its preference for a certain host and analyses throughout the years to classify the genus Brucella and its strains, depended on the techniques used, the number of strains or the methods of phylogenetic reconstruction. Its history goes from recognizing the entire genus as unique B. mellitensis species with multiple varieties, to recognizing more than ten species. This review shows the journey through the techniques that have been used to differentiate the genus Brucella, which, although they have generated clarity in the grouping of some species, still leaves doubts in related to the oldest species, their divergence and the type of grouping of the new species discovered. The application of new technologies such as phylogenomics is contributing to solve these questions.
RESUMEN Las especies del género Brucella son patógenos de distribución mundial que afecta, tanto a los animales como al hombre, los cuales, presentan baja variabilidad genética, convirtiéndolo en un reto para su reconstrucción filogenética y diferenciación. La diferenciación originalmente se dio, debido a su preferencia por cierto hospedero. A través de los años, se han realizado diferentes análisis para clasificar el género Brucella y las variaciones que presenta, que dependen de las técnicas empleadas para su clasificación, las especies, el número de cepas o los métodos de reconstrucción filogenética. La historia pasa desde reconocer a todo el género como una única especie B. mellitensis con múltiples variedades, a reconocer más de diez especies. En esta revisión, se hace una travesía, a través de las diferentes técnicas que se han utilizado en el tiempo, para clasificar el género Brucella que, aunque han generado claridad en el agrupamiento de algunas especies, aun dejan dudas en relación a las especies más antiguas, su divergencia y el tipo de agrupación de las nuevas especies descubiertas. La aplicación de nuevas tecnologías, como la filogenómica, está contribuyendo a resolver estos interrogantes.
RESUMEN
Serpin peptidase inhibitor clade E member 2(SerpinE2),a member of serine peptidase inhibitor super family,regulates multiple serine proteases.Extracellular matrix(ECM)plays an important role in stem cell differen-tiation,signal transduction,tumor metastasis,osteoarthritis physiological and pathological processes and so on.SerpinE2 regulates the protein of extracellular matrix by serine protease system and matrix metalloproteinase(MMP)system.In this paper,we elaborate the effect of SerpinE2 on metabolism of extracellular matrix,and it will provide new ideas to find new therapeutic targets.
RESUMEN
Novel H5N6 highly pathogenic avian influenza viruses (HPAIVs) were isolated from duck farms and migratory bird habitats in South Korea in November to December 2017. Genetic analysis demonstrated that at least two genotypes of H5N6 were generated through reassortment between clade 2.3.4.4 H5N8 HPAIVs and Eurasian low pathogenic avian influenza virus in migratory birds in late 2017, suggesting frequent reassortment of clade 2.3.4.4 H5 HPAIVs and highlighting the need for systematic surveillance in Eurasian breeding grounds.
Asunto(s)
Animales , Agricultura , Aves , Cruzamiento , Patos , Ecosistema , Heterogeneidad Genética , Genotipo , Gripe Aviar , Corea (Geográfico)RESUMEN
A new mouth breeder species of Gymnogeophagus is described from a tributary of the río Uruguay. It is distinguished from most species of the genus by the presence of hypertrophied lips, and from G. labiatus and G. pseudolabiatus by the color pattern. The presence of successive allopatric species of the Gymnogeophagus gymnogenys clade inhabiting the tributaries of the río Uruguay is discussed.(AU)
Una nueva especie incubadora bucal de Gymnogeophagus es descripta de un tributario del Río Uruguay. Se distingue de la mayoría de las especies del género por la presencia de labios hipertrofiados, y de G. labiatus y G. pseudolabiatus por su patrón de coloración. Se discute la presencia de sucesivas especies alopátricas del clado Gymnogeophagus gymnogenys habitando los tributarios del Río Uruguay.(AU)
Asunto(s)
Animales , Perciformes/clasificación , Hipertrofia Gingival/veterinariaRESUMEN
Pimelodidae harbors several species and is widely distributed throughout the Neotropical region. Pimelodus is the genus with the largest number of species, however it is a polyphyletic group. Cytogenetic analyzes of the valid species still covers less than half of them. Herein, seven Pimelodus species from three Brazilian hydrographic systems were analyzed through basic (Giemsa, AgNORs and C banding) and molecular (5S and 18S rDNA-FISH) cytogenetic methods. All species had 2n=56 chromosomes with different karyotype formulas observed among the species. AgNORs were corresponding to 18S rDNA and localized on long arm of one chromosome pair in all species. Heterochromatin distribution follows the pattern commonly verified in the family and allows to identify each one of the studied species. 5S rDNA marker was interspecifically variable in number and position of cistrons. Pimelodus ortmanni had B chromosomes varying intra and inter-individually. We performed a discussion on our own and available cytogenetic data for Pimelodidae, and the associating of them with available phylogeny enable us identifying features that distinguish subgroups within Pimelodidae, such as NORs location (terminal/long arm for species belonging to "Iheringichthys-Parapimelodus" and "Pimelodus maculatus" subclades) and location of 5S rDNA sites (pericentromeric/interstitial/ long arm for species belonging to Pimelodus group).(AU)
Pimelodidae abriga várias espécies e é amplamente distribuída ao longo da região Neotropical. Pimelodus é o gênero com o maior número de espécies, porém é um grupo polifilético. Análises citogenéticas foram realizadas em menos da metade das espécies válidas. Aqui, sete espécies de Pimelodus de três sistemas hidrográficos brasileiros foram estudadas através das técnicas citogenéticas básicas (Giemsa, AgRONs e banda C) e moleculares (FISH-DNAr 5S e 18S). Todas as espécies apresentaram 2n=56 cromossomos, sendo observadas variações na fórmula cariotípica entre algumas espécies. As AgRONs correspondentes ao DNAr 18S foram localizadas no braço longo de um par de cromossomos em todas as espécies. A heterocromatina segue o padrão comumente observado na família e permite identificar cada uma das espécies estudadas. O DNAr 5S apresentou variação interespecífica em número e na posição dos cístrons. Cromossomos B foram evidenciados em P. ortmanni com variação intra e interindividual. Nós discutimos os nossos resultados com os dados citogenéticos válidos para Pimelodidae, e a associação desses dados com a filogenia válida nos permitiu identificar características que distinguem subgrupos dentro de Pimelodidae, tais como a localização das RONs (terminal/braço longo para espécies pertencentes aos subclados "Iheringichthys-Parapimelodus" e "Pimelodus maculatus") e localização dos sítios de DNAr 5S (pericentromérico/intersticial no braço longo para espécies pertencentes ao grupo Pimelodus).(AU)
Asunto(s)
Animales , Bagres/genética , Heterocromatina , CitogenéticaRESUMEN
BACKGROUND Human herpesvirus 2 (HHV-2) have DNA genome with a limited genetic variability and have been classified into two clades. OBJECTIVES To identify and characterise six HHV-2 isolates derived from Brazilian women. METHODS HHV-2 isolates were performed polymerase chain reaction (PCR) and sequencing of 2250 pb of the glycoprotein B (gB) coding regions. FINDINGS Four HHV-2 isolates were classified into clade B, while the remaining two, derived from HIV-1 co-infected women, showed a notable genetic divergence (> 1%). MAIN CONCLUSION The results reveal novel HHV-2 variants. The impact of these novel variants on HHV-2 pathogenesis and HIV/HHV-2 coinfection need to be investigated.
Asunto(s)
Humanos , Femenino , Herpes Genital/virología , Infecciones por VIH/virología , VIH-1 , Herpesvirus Humano 2/genética , Genes Virales/genética , Filogenia , Herpes Genital/complicaciones , Infecciones por VIH/complicaciones , Reacción en Cadena de la Polimerasa , Bertholletia , Coinfección/virologíaRESUMEN
Abstract Herein, we provide new occurrence records of Scinax nasicus (Cope, 1862) for the state of Rio Grande do Sul, Southern Brazil. All new records here provide are located on Southern half of the state. Besides this, we provide the first record for species in Brazilian coastal zone. Those records improve considerably our knowledge regarding species distribution in Southern Brazil.
Resumo Aqui, nós fornecemos novos registros de ocorrência de Scinax nasicus (Cope, 1862) para o estado do Rio Grande do Sul, Sul do Brasil. Todos os novos registros aqui fornecidos estão localizados na metade sul do estado. Além disso, nós fornecemos o primeiro registro para a espécie na zona costeira brasileira. Esses registros melhoram consideravelmente o nosso conhecimento sobre a distribuição da espécie no Sul do Brasil.
Asunto(s)
Animales , Anuros/fisiología , Distribución Animal , BrasilRESUMEN
A new species of Boehlkea is described from rio Japurá, Amazon basin. The new species differs from B. fredcochui by the presence of a vertically elongate humeral spot (vs. absence), complete lateral line (vs. incomplete), four rows of scales below lateral line (vs. three), and lower number of branched anal-fin rays (17-21 vs. 22-25), and from B. orcesi by the higher number of maxillary teeth (13-14 vs. 5-12), greater head length (27.9-29.9% vs. 24.3-27.5% of SL), and by the color pattern (basal half of dorsal-fin, distal portion of pelvic-fin, lower caudal-fin lobe and anal-fin with black chromatophores vs. absence of black chromatophores in the fins).(AU)
Uma nova espécie de Boehlkea é descrita do rio Japurá, bacia Amazônica. A espécie nova difere de B. fredcochui pela presença de uma mancha umeral verticalmente alongada (vs. ausência), linha lateral completa (vs. incompleta), quatro séries de escamas abaixo da linha lateral (vs. três), e menor número de raios ramificados na nadadeira anal (17-21 vs. 22-25), e de B. orcesi pelo maior número de dentes no maxilar (13-14 vs. 5-12), maior comprimento da cabeça (27,9-29,9% vs. 24,3-27,5% do CP), e pelo padrão de colorido (porção inferior da nadadeira dorsal, porção distal da nadadeira pélvica, lobo inferior das nadadeiras caudal e anal com cromatóforos pretos vs. ausência de cromatóforos pretos nas nadadeiras)(AU)
Asunto(s)
Animales , Sistema de la Línea Lateral/anatomía & histología , Characiformes/clasificación , ClasificaciónRESUMEN
During 2006, H5N1 HPAI caused an epizootic in wild birds, resulting in a die-off of Laridae in the Novosibirsk region at Chany Lake. In the present study, we infected common gulls (Larus canus) with a high dose of the H5N1 HPAI virus isolated from a common gull to determine if severe disease could be induced over the 28 day experimental period. Moderate clinical signs including diarrhea, conjunctivitis, respiratory distress and neurological signs were observed in virus-inoculated birds, and 50% died. The most common microscopic lesions observed were necrosis of the pancreas, mild encephalitis, mild myocarditis, liver parenchymal hemorrhages, lymphocytic hepatitis, parabronchi lumen hemorrhages and interstitial pneumonia. High viral titers were shed from the oropharyngeal route and virus was still detected in one bird at 25 days after infection. In the cloaca, the virus was detected sporadically in lower titers. The virus was transmitted to direct contact gulls. Thus, infected gulls can pose a significant risk of H5N1 HPAIV transmission to other wild migratory waterfowl and pose a risk to more susceptible poultry species. These findings have important implications regarding the mode of transmission and potential risks of H5N1 HPAI spread by gulls.
Asunto(s)
Animales , Aves , Charadriiformes , Cloaca , Conjuntivitis , Diarrea , Encefalitis , Hemorragia , Hepatitis , Subtipo H5N1 del Virus de la Influenza A , Lagos , Hígado , Enfermedades Pulmonares Intersticiales , Miocarditis , Necrosis , Páncreas , Patología , Aves de Corral , VirulenciaRESUMEN
The type-species of Hyphessobrycon is redescribed and its osteology provided. Hyphessobrycon compressus is distinguished from its congeners by the 41-48 (mode 45) scales in the longitudinal series; 7-9 (mode 9) scales rows between the dorsal-fin origin and the lateral line, and absence of predorsal scales. Additional useful characters include the lack of spots on the body, a dorsal fin with a black spot, and an anal fin with two large, conspicuous hooks, and several other small hooks. Hyphessobrycon milleri is proposed as a junior synonym of H. compressus. The osteology of H. compressus is discussed in detail together with comments about phylogenetic relationships of Hyphessobrycon sensu stricto.
A espécie-tipo de Hyphessobrycon é redescrita, junto com sua descrição osteológica. Hyphessobrycon compressus é distinguido dos seus congêneres por possuir 41-48 (moda 45) escamas na série longitudinal, 7-9 (moda 9) séries de escamas entre a origem da nadadeira dorsal e a linha lateral, e pela ausência de escamas pré-dorsais. Caracteres adicionais úteis incluem a ausência de máculas no flanco, nadadeira dorsal com mácula preta e nadadeira anal com dois ganchos ósseos grandes e conspícuos e vários outros pequenos. Hyphessobrycon millerié proposto como sinônimo júnior de H. compressus. A osteologia de H. compressusé discutida em detalhe, junto com comentários sobre as relações filogenéticas de Hyphessobrycon sensu stricto.
Asunto(s)
Animales , Characidae/anatomía & histología , Characidae/clasificación , Characidae/genética , Osteología/clasificación , Osteología/historiaRESUMEN
In this study, phylogenetic and phylogeographic analyses of populations identified as Hypostomus strigaticeps from the upper Paraná River basin were conducted in order to test whether these different populations comprises cryptic species or structured populations and to assess their genetic variability. The sequences of the mitochondrial DNA ATP sintetase (subunits 6/8) of 27 specimens from 10 populations (one from Mogi-Guaçu River, five from Paranapanema River, three from Tietê River and one from Peixe River) were analyzed. The phylogeographic analysis showed the existence of eight haplotypes (A-H), and despite the ancestral haplotype includes only individuals from the Tietê River basin, the distribution of H. strigaticeps was not restricted to this basin. Haplotypes A, B and F were the most frequent. Haplotypes D, E, F, G, and H were present in the sub-basin of Paranapanema, two (A and B) were present in the sub-basin of the Tietê River, one (C) was exclusively distributed in the sub-basin of the Peixe River, and one (B) was also present in the sub-basin of the Grande River. The phylogenetic analysis showed that the populations of H. strigaticeps indeed form a monophyletic unit comprising two lineages: TG, with representatives from the Tietê, Mogi-Guaçu and Peixe Rivers; and PP, with specimens from the Paranapanema River. The observed degree of genetic divergence within the TG and PP lineages was 0.1% and 0.2%, respectively, whereas the genetic divergence between the two lineages themselves was approximately 1%. The results of the phylogenetic analysis do not support the hypothesis of existence of crypt species and the phylogeographic analysis confirm the presence of H. strigaticeps in other sub-basins of the upper Paraná River: Grande, Peixe, and Paranapanema sub-basins.
Neste estudo, foram conduzidas análises filogenéticas e filogeográficas de populações identificadas como Hypostomus strigaticeps na bacia do alto rio Paraná a fim de testar se essas populações compreendem espécies crípticas ou populações estruturadas e avaliar a variabilidade genética das mesmas. Foram analisadas sequências do DNA mitocondrial ATP sintetase (subunidades 6/8) de 27 espécimes de 10 populações (uma do rio Mogi-Guaçu, cinco do rio Paranapanema, três do rio Tietê e uma do rio do Peixe). A análise filogeográfica mostrou a existência de oito haplótipos (A-H), e apesar do haplótipo ancestral incluir apenas indivíduos da bacia do rio Tietê, a distribuição de H. strigaticeps não se restringe a esta bacia. Os haplótipos A, B e F foram os mais frequentes. D, E, F, G e H estão presentes na sub-bacia do rio Paranapanema, dois (A e B) estão presentes na sub-bacia do rio Tietê, um (C) está exclusivamente distribuído na sub-bacia do rio do Peixe, e um (B) também está presente na sub-bacia do rio Grande. A análise filogenética mostrou que as populações de H. strigaticeps realmente formam uma unidade monofilética que compreende duas linhagens: TG, com representantes do rio Tietê, rio Mogi-Guaçu e rio do Peixe, e PP, com espécimes do rio Paranapanema. O grau de divergência genética observada nas linhagens de TG e PP foram de 0,1% e 0,2%, respectivamente, enquanto que a divergência genética entre as duas linhagens foi de aproximadamente 1%. Os resultados da análise filogenética não suportam a hipótese da existência de espécies crípticas e a análise filogeográfica confirma a presença de H. strigaticeps em outras sub-bacias do alto rio Paraná: sub-bacias do rio Grande, rio do Peixe e rio Paranapanema.
Asunto(s)
Animales , Characiformes/anatomía & histología , Distribución Animal/fisiología , Aletas de Animales/anatomía & histología , Ríos , Especificidad de la EspecieRESUMEN
The structure and form of gill gland among inseminating and externally fertilizing species of the Cheirodontinae are described under light microscopy, scanning electron microscopy, and transmission electron microscopy, and compared to other members of the family Characidae. At least one species from thirteen cheirodontine genera were analyzed, totaling seventeen species. Gill glands were found in all analyzed mature males of Cheirodontinae and were always absent in females, being located on the anteriormost portion of the lower branch of the first gill arch, extending posteriorly through a variable number of gill filaments. Gill glands of all cheirodontines and of all characid species in which this organ has been described possess the same structure, being considered homologous and supporting a single origin of the structure in a common ancestor to Clade A and Clade B characids.
A estrutura e forma da glândula branquial de queirodontíneos inseminadores e de fecundação externa são descritas com base em análises de microscopia óptica, microscopia eletrônica de varredura e microscopia eletrônica de transmissão, e comparadas com outros membros da família Characidae. Pelo menos uma espécie de treze gêneros de Cheirodontinae foram analisadas, num total de dezessete espécies. Glândulas branquiais foram encontradas em todos os machos maduros analisados de Cheirodontinae, localizadas na parte mais anterior do ramo inferior do primeiro arco branquial, estendendo-se posteriormente por um número variável de filamentos branquiais, estando sempre ausentes nas fêmeas. As glândulas branquiais de todos os queirodontíneos analisados e de todas as espécies de Characidae em que este órgão foi descrito possuem a mesma estrutura, sendo consideradas homólogas e suportando uma origem única em um ancestral comum aos Clados A e B de Characidae.
Asunto(s)
Animales , Characiformes/anatomía & histología , Fertilización/genética , Filogenia , Región Branquial/anatomía & histología , Benchmarking/métodos , Characiformes/crecimiento & desarrolloRESUMEN
The monophyly and phylogenetic relationships among the members of Clade A characids (sensu Malabarba & Weitzman), later redefined and named as the Stevardiinae (sensu Mirande), have been primarily supported by traditional morphological and molecular data. Herein were examined, described and compared spermiogenesis and sperm ultrastructure of 12 species of the genera Boehlkea, Bryconacidnus, Bryconamericus, Creagrutus, Cyanocharax, Hemibrycon, Knodus, Odontostoechus, Piabina, and Rhinobrycon in order to evaluate possible phylogenetic signals and their potential use in recovering relationships of the Stevardiinae. All examined species demonstrated a nuclear rotation equal or less than 95º resulting in a lateral position of the double nuclear fossa and flagellum. In all species, sperm nuclei are slightly elongate toward the flagellum, the proximal centriole is partially inside the nuclear fossa and lies anterior and oblique to the distal centriole, and the midpiece is short and strongly asymmetric. All species analyzed herein and other species previously examined for these systems in the Stevardiinae share homologous sperm characteristics as evidenced by spermiogenesis, further supporting the monophyly of this clade. Spermatozoa of the Stevardiinae further show three morphotypes (M1, M2, M3) of arrangement of centrioles, flagellum, nucleus and midpiece, hypothesized as successively derived in a series of transformation from the most basal morphotype (M1).
A monofilia e filogenia dos membros do Clado A (sensu Malabarba & Weitzman), mais tarde redefinido e nomeado Stevardiinae (sensu Mirande), é suportada por dados morfológicos e moleculares. Aqui são examinadas, descritas e comparadas a espermiogênese e ultraestrutura do espermatozoide de 12 espécies dos gêneros Boehlkea, Bryconacidnus, Bryconamericus, Creagrutus, Cyanocharax, Hemibrycon, Knodus, Odontostoechus, Piabina e Rhinobrycon, a fim de avaliar possíveis sinais filogenéticos e seu uso potencial no estudo de relações filogenéticas em Stevardiinae. Em todas as espécies examinadas observa-se uma rotação nuclear igual ou menor que 95º, resultando em uma posição lateral da fossa nuclear dupla e do flagelo. Em todas as espécies o núcleo do espermatozoide é alongado em direção ao flagelo, o centríolo proximal é anterior e oblíquo ao centríolo distal e localiza-se parcialmente inserido na fossa nuclear, e a peça intermediária é pequena e fortemente assimétrica. Todas as espécies de Stevardiinae analisadas aqui e outras analisadas previamente compartilham características homólogas dos espermatozoides evidenciadas por sua espermiogênese, corroborando a monofilia deste clado. Os espermatozoides de Stevardiinae apresentam ainda três morfotipos (M1, M2, M3) de acordo com o arranjo dos centríolos, flagelo e peça intermediária, considerados como sucessivamente derivados em uma série de transformações a partir do morfotipo mais basal (M1).
Asunto(s)
Animales , Espermatogénesis/genética , Peces , FilogeniaRESUMEN
The genus Markiana was until recently recognized as incertae sedis in the family Characidae, even though alternative placements for this genus have been advanced since its original description. More recently, it was hypothesized that Markiana nigripinnis is part of a clade informally named the Astyanax clade, indicating the putative close relationship of Markiana with the genus Astyanax. Examination of sperm ultrastructure of representatives of Astyanax and M. nigripinnis shows no evidence for this hypothesized close relationship. Rather, the spermatozoa of M. nigripinnis share characters found in spermatozoa of the non-inseminating members of the subfamily Stevardiinae, such as an angle of nuclear rotation equal to 85º resulting in a lateral position of the double nuclear fossa and flagellum. As with the non-inseminating Stevardiinae, sperm nuclei are also slightly elongate toward the flagellum, the proximal centriole is partially inside the nuclear fossa and anterior and oblique to the distal centriole, and the midpiece is short and strongly asymmetric. Additionally, M. nigripinnis shares with the other members of the Stevardiinae the presence of only four teeth in the inner row of the premaxillary and a short triangular ectopterygoid, which is never more than twice the length of the palatine.
O gênero Markiana até recentemente foi reconhecido como incertae sedis na família Characidae, apesar da localização alternativa para este gênero desde sua descrição original. Mais recentemente, surgiu a hipótese de que Markiana nigripinnis faz parte de um clado chamado informalmente de "Astyanax clade", indicando a suposta relação de Markiana com o gênero Astyanax. A análise da ultraestrutura dos espermatozoides de representantes do gênero Astyanax e M. nigripinnis não mostra nenhuma evidência de estreita relação. Pelo contrário, os espermatozóides de M. nigripinnis compartilham o padrão encontrado nos espermatozoides dos membros não-inseminadores da subfamília Stevardiinae, tais como, um ângulo de rotação nuclear igual a 85º resultando em uma posição de lateral da fossa dupla nuclear e do flagelo. Assim como nos Stevardiinae não inseminadores, os núcleos dos espermatozoides também são ligeiramente alongados em direção ao flagelo, o centríolo proximal é anterior e oblíquo em relação ao centríolo distal e parcialmente inserido na fossa nuclear, e a peça intermediária é curta e fortemente assimétrica. Além disso, M. nigripinnis compartilha com os outros membros da Stevardiinae a presença de apenas quatro dentes na série interna da pré-maxila e um osso ectopterigoide curto e triangular, que nunca ultrapassa o dobro do comprimento do osso palatino.
Asunto(s)
Animales , Espermatogénesis/genética , Peces/anatomía & histología , Microscopía Electrónica de Transmisión/veterinariaRESUMEN
The genotypes of dengue viruses (DENV) isolated from patients with dengue in Jamaica during 2007 were determined using DNA sequencing and phylogenetic analysis of the C-prM gene junction. The 17 DENV analysed included strains of DENV serotypes 1 (DENV-1, n = 3), DENV-2 (n = 7) and DENV-4 (n = 7). All strains of DENV-1 were classified as genotype III, while 1 of 7 strains of DENV-2 belonged to the Asian American/Asian genotype, genotype I/ III (Jamaica genotype), 2 were genotype V, the American genotype and 4 strains clustered with reference strains belonging to genotype IV. The 6 DENV-4 strains from Jamaica and the control strain clustered together in a separate clade from Caribbean/ American reference strains, which belong to genotype II and Asian strains, classified as genotypes I and III. There has been little evolution in the DENV-1 strains circulating in Jamaica over the years and this might reduce the risk of outbreaks due to this serotype. In contrast, the high genetic diversity in strains of DENV-2 viruses in circulation, the presence of more recently introduced genotypes and a new clade of DENV-4 might contribute to the epidemic potential of these DENV serotypes. These preliminary data clearly indicate the need to maintain laboratory surveillance, and other control measures against hyperendemicity of dengue in Jamaica.
Los genotipos de los virus del dengue (DENV) aislados de pacientes con dengue en Jamaica durante 2007, fueron determinados usando secuenciación de ADN y análisis filogenético de la unión del gen C-prM . Los 17 DENV analizados incluyeron cepas de serotipos de DENV 1 (DENV-1, n = 3), DENV-2 (n = 7) y DENV-4 (n = 7). Todas las cepas de DENV-1 fueron clasificadas como genotipo III, mientras que 1 de 7 cepas de DENV-2 pertenecían al genotipo asiático americano/asiático, genotipo I/ III (genotipo de Jamaica), 2 fueron genotipo V, el genotipo americano y 4 cepas agrupadas con cepas de referencia pertenecientes al genotipo IV. Las 6 cepas DENV-4 de Jamaica y la cepa de control se agruparon en un clado aparte de cepas de referencia caribeña/americana, que pertenecen al genotipo II, y las cepas asiáticas, clasificadas como genotipos I y III. Ha habido poca evolución en las cepas DENV-1 que han estado circulando en Jamaica a través de todos estos años, y esto podría reducir el riesgo de brotes a causa de este serotipo. En contraste con ello, la alta diversidad genética de las cepas de los virus DENV-2 en circulación, la presencia de más genotipos introducidos recientemente, y un nuevo clado de DENV-4 podrían contribuir al potencial epidémico de estos serotipos de DENV. Estos datos preliminares indican claramente la necesidad de mantener la vigilancia de laboratorio, y otras medidas de control contra el carácter hyperendémico del dengue en Jamaica.