Chromosomal Evolution and Evolutionary Relationships of Lebiasina Species (Characiformes, Lebiasinidae)

We present the first cytogenetic data for Lebiasina bimaculata and L. melanoguttata with the aim of (1) investigating evolutionary events within Lebiasina and their relationships with other Lebiasinidae genera and (2) checking the evolutionary relationships between Lebiasinidae and Ctenoluciidae. Both species have a diploid number 2n = 36 with similar karyotypes and microsatellite distribution patterns but present contrasting C-positive heterochromatin and CMA3 + banding patterns. The remarkable interstitial series of C-positive heterochromatin occurring in L. melanoguttata is absent in L. bimaculata. Accordingly, L. bimaculata shows the ribosomal DNA sites as the only GC-rich (CMA3 +) regions, while L. melanoguttata shows evidence of a clear intercalated CMA3 + banding pattern. In addition, the multiple 5S and 18S rDNA sites in L. melanogutatta contrast with single sites present in L. bimaculata. Comparative genomic hybridization (CGH) experiments also revealed a high level of genomic differentiation between both species. A polymorphic state of a conspicuous C-positive, CMA3 +, and (CGG)n band was found only to occur in L. bimaculata females, and its possible relationship with a nascent sex chromosome system is discussed. Whole chromosome painting (WCP) and CGH experiments indicate that the Lebiasina species examined and Boulengerella maculata share similar chromosomal sequences, thus supporting the relatedness between them and the evolutionary relationships between the Lebiasinidae and Ctenoluciidae families

Centric fusions behind the karyotype evolution of neotropical nannostomus pencilfishes (Characiforme, Lebiasinidae): First insights from a molecular cytogenetic perspective

Lebiasinidae is a Neotropical freshwater family widely distributed throughout South and Central America. Due to their often very small body size, Lebiasinidae species are cytogenetically challenging and hence largely underexplored. However, the available but limited karyotype data already suggested a high interspecific variability in the diploid chromosome number (2n), which is pronounced in the speciose genus Nannostomus, a popular taxon in ornamental fish trade due to its remarkable body coloration. Aiming to more deeply examine the karyotype diversification in Nannostomus, we combined conventional cytogenetics (Giemsa-staining and C-banding) with the chromosomal mapping of tandemly repeated 5S and 18S rDNA clusters and with interspecific comparative genomic hybridization (CGH) to investigate genomes of four representative Nannostomus species: N. beckfordi, N. eques, N. marginatus, and N. unifasciatus. Our data showed a remarkable variability in 2n, ranging from 2n = 22 in N. unifasciatus (karyotype composed exclusively of metacentrics/submetacentrics) to 2n = 44 in N. beckfordi (karyotype composed entirely of acrocentrics). On the other hand, patterns of 18S and 5S rDNA distribution in the analyzed karyotypes remained rather conservative, with only two 18S and two to four 5S rDNA sites. In view of the mostly unchanged number of chromosome arms (FN = 44) in all but one species (N. eques; FN = 36), and with respect to the current phylogenetic hypothesis, we propose Robertsonian translocations to be a significant contributor to the karyotype differentiation in (at least herein studied) Nannostomus species. Interspecific comparative genome hybridization (CGH) using whole genomic DNAs mapped against the chromosome background of N. beckfordi found a moderate divergence in the repetitive DNA content among the species’ genomes. Collectively, our data suggest that the karyotype differentiation in Nannostomus has been largely driven by major structural rearrangements, accompanied by only low to moderate dynamics of repetitive DNA at the sub-chromosomal level. Possible mechanisms and factors behind the elevated tolerance to such a rate of karyotype change in Nannostomus are discussed. © 2020 by the authors. Licensee MDPI, Basel, Switzerland

Cytogenetics of the small-sized fish, Copeina guttata (Characiformes, Lebiasinidae): Novel insights into the karyotype differentiation of the family

Lebiasinidae is a small fish family composed by miniature to small-sized fishes with few cytogenetic data (most of them limited to descriptions of diploid chromosome numbers), thus preventing any evolutionary comparative studies at the chromosomal level. In the present study, we are providing, the first cytogenetic data for the red spotted tetra, Copeina guttata, including the standard karyotype, C-banding, repetitive DNA mapping by fluorescence in situ hybridization (FISH) and comparative genomic hybridization (CGH), providing chromosomal patterns and novel insights into the karyotype differentiation of the family. Males and females share diploid chromosome number 2n = 42 and karyotype composed of 2 metacentric (m), 4 submetacentric (sm) and 36 subtelocentric to acrocentric (st-a) chromosomes. Blocks of constitutive heterochromatin were observed in the centromeric and interstitial regions of several chromosomes, in addition to a remarkably large distal block, heteromorphic in size, which fully corresponded with the 18S rDNA sites in the fourth chromosomal pair. This overlap was confirmed by 5S/18S rDNA dual-color FISH. On the other hand, 5S rDNA clusters were situated in the long and short arms of the 2nd and 15th pairs, respectively. No sex-linked karyotype differences were revealed by male/female CGH experiments. The genomic probes from other two lebiasinid species, Lebiasina melanoguttata and Pyrrhulina brevis, showed positive hybridization signals only in the NOR region in the genome of C. guttata. We demonstrated that karyotype diversification in lebiasinids was accompanied by a series of structural and numeric chromosome rearrangements of different types, including particularly fusions and fissions. © 2019 Toma et al

An Insight into the Chromosomal Evolution of Lebiasinidae (Teleostei, Characiformes)

Lebiasinidae fishes have been historically neglected by cytogenetical studies. Here we present a genomic comparison in eleven Lebiasinidae species, in addition to a review of the ribosomal DNA sequences distribution in this family. With that, we develop ten sets of experiments in order to hybridize the genomic DNA of representative species from the genus Copeina, Copella, Nannostomus, and Pyrrhulina in metaphase plates of Lebiasina melanoguttata. Two major pathways on the chromosomal evolution of these species can be recognized: (i) conservation of 2n = 36 bi-armed chromosomes in Lebiasininae, as a basal condition, and (ii) high numeric and structural chromosomal rearrangements in Pyrrhulininae, with a notable tendency towards acrocentrization. The ribosomal DNA (rDNA) distribution also revealed a marked differentiation during the chromosomal evolution of Lebiasinidae, since both single and multiple sites, in addition to a wide range of chromosomal locations can be found. With some few exceptions, the terminal position of 18S rDNA appears as a common feature in Lebiasinidae-analyzed species. Altogether with Ctenoluciidae, this pattern can be considered a symplesiomorphism for both families. In addition to the specific repetitive DNA content that characterizes the genome of each particular species, Lebiasina also keeps inter-specific repetitive sequences, thus reinforcing its proposed basal condition in Lebiasinidae

A SAÚDE BUCAL NA PERCEPÇÃO DOS USUÁRIOS DE UM RESTAURANTE POPULAR LOCALIZADO EM UMA CIDADE MÉDIO PORTE DA PARAÍBA

A prevenção em odontologia tem tido ênfase ultimamente. Os cuidados com a saúde bucal têm ido além da visão estética. O presente estudo visa avaliar a autopercepção da saúde bucal dos usuários do Restaurante Popular da Cidade de Patos/PB. Trata-se de um estudo transversal, foi aplicado um questionário com questões abordando variáveis socioeconômicas e sobre saúde bucal.  Em seguida os dados foram analisados através do software Statistical Package for the Social Sciences (SPSS) versão 22.0.  Foram avaliados 252 usuários por meio dos questionários, uma maior prevalência para o sexo masculino (56,3%), com relação ao grau de escolaridade, o que obteve maior frequência foi o ensino médio completo (30,7%) seguido do ensino fundamental incompleto (29%). Com relação à autovaliação da saúde bucal, 49,2 % classificam como “boa”, 28,7% consideraram sua saúde bucal “regular”, 6,3% dos participantes da pesquisa declararam ter a saúde bucal “ruim”. Quando indagados sobre a participação de atividades em promoção de saúde bucal, a maioria dos participantes já participou (81,9%) de alguma atividade ao longo da vida. No que diz respeito à frequência de escovação 92,5% dos usuários marcaram a resposta “duas vezes ou mais por dia”, com relação à periodicidade de visitas ao dentista uma parcela de 11% dos participantes afirmou não ter visitado o dentista há três anos ou mais, outros 2% falaram nunca ter consultado o dentista. Dessa forma, concluiu-se que os usuários que frequentaram o Restaurante Popular na cidade de Patos-PB fizeram uma avaliação positiva de sua condição bucal.

Desafios e avanços na antibioticoterapia para exacerbações pulmonares na fibrose cística

A fibrose cística é uma doença genética complexa que afeta a produção de muco e a função pulmonar. Exacerbações pulmonares, muitas vezes provocadas por Pseudomonas aeruginosa, são comuns. O diagnóstico requer testes de suor e genéticos para guiar a terapia antibiótica. Avanços com moduladores CFTR melhoram a função pulmonar, mas desafios como resistência bacteriana persistem. Este estudo busca analisar a antibioticoterapia para exacerbações pulmonares na fibrose cística, com foco em abordagens inovadoras e personalizadas. O estudo, baseado em uma revisão sistemática da literatura científica, abrange o período de 2016 a 2024, utilizando as bases de dados PubMed (Medline), Cochrane Library e Scientific Electronic Library Online (SciELO). No primeiro estudo, sobre adjuvantes antibióticos no tratamento de infecções pulmonares em pacientes com fibrose cística, não houve impacto significativo nas exacerbações pulmonares ou na função respiratória. O KB001-A não alterou o tempo para a próxima administração de antibióticos em comparação ao placebo. Evidências apontam uma possível redução na densidade de Pseudomonas aeruginosa com o KB001-A e reduções em Staphylococcus aureus e quase-Pseudomonas aeruginosa com o óxido nítrico, sem diferenças na qualidade de vida. O segundo estudo, em um modelo suíno de pneumonia por Pseudomonas aeruginosa multirresistente, a terapia inalatória de amicacina combinada com meropenem mostrou maior eficácia bactericida nas secreções traqueais em comparação à monoterapia intravenosa. A administração inalatória não preveniu a disseminação da infecção, mas a amicacina evitou o aumento da concentração inibitória mínima de meropenem, com alta concentração nas amostras sem diferenças entre pulmões infectados e não infectados. No terceiro estudo, O estudo das nanopartículas poliméricas na eliminação de biofilmes bacterianos em cepas resistentes e suscetíveis associadas à fibrose cística mostrou potencial promissor contra bactérias multirresistentes. Os nanoportadores de lipídios demonstraram eficácia terapêutica significativa, ressaltando a necessidade de mais pesquisas para confirmar seu benefício clínico. Em resumo, os adjuvantes antibióticos não impactaram significantemente o tratamento de infecções pulmonares na fibrose cística. A combinação de amicacina e meropenem foi eficaz contra pneumonia por Pseudomonas aeruginosa multirresistente. As nanopartículas poliméricas e nanoportadores de lipídios mostraram potenciais terapêuticos promissores, demandando mais pesquisas para validar seus benefícios clínicos

Relações filogenéticas e revisão taxonômica das espécies do gênero Copella Myers, 1956 (Characiformes: Lebiasinidae)

A hypothesis of the phylogenetic relationships of the genus Copella is proposed on the basis of the parsimony analysis of 120 morphological characters found in all the species of the genus recognized as valid in the taxonomic review, and 17 outgroup taxa, most of them members of the family Lebiasinidae. The genus is corroborated as monophyletic based on 38 synapomorphies, of which 13 are exclusive, 19 homoplastic, and six dependent of optimization. Copella arnoldi is the basal taxa, sister of a clade including the remaining species of the genus. The clade represented by Copella nattereri and C. stigmasemion is sister group of the clade (C. eigenmanni (Copella compta and C. vilmae)). Copella is sister of Pyrrhulina, and both are members of the subfamily Pyrrhulininae characterized by having several bony losses and reductions related to the complexity of the sculpturing of their skeleton, especially in Copella and Pyrrhulina, when compared to species of Lebisininae. Based on the results of the phylogenetic analysis and on the observation of the ontogenetic series of several representatives of Lebiasinidae, it is supposed that many morphological traits present in the Pyrrhulininae have evolved through developmental truncation of characters. Based on the analysis of the type material of all nominal species and of a large number of specimens of Copella from several drainages in South America, six out of ten nominal species are recognized as valid: Copella arnoldi, C. compta, C. eigenmanni, C. nattereri, C. stigmasemion, and C. vilmae. Copella arnoldi is considered senior synonym of C. carsevennensis, C. eigenmanni is a senior synonym of C. metae, C. nattereri is a senior synonym of C. callolepis and C. meinkeni, and C. stigmasemion, new combination, is a senior synonym of C. nigrofasciata. The species Copella occur in the rio Amazonas and Orinoco basins, and coastal drainages of Guyana, French Guiana, Surinam, and VenezuelaUma hipótese de relações filogenéticas do gênero Copella é proposta com base na análise de parcimônia de 120 caracteres morfológicos de todas as espécies do gênero reconhecidas como válidas na revisão taxonômica, e de 17 táxons do grupo externo, a maioria membros da família Lebiasinidae. O gênero é corroborado como monofilético com base em 38 sinapomorfias, das quais 13 são exclusivas, 19 homoplásticas, e seis dependentes de otimização. Copella arnoldi é o taxon basal, espécie irmã do clado composto por todas as demais espécies do gênero. O clado que inclui Copella nattereri e C. stigmasemion é grupo irmão do clado (C. eigenmanni (Copella compta and C. vilmae)). Copella é grupo irmão de Pyrrhulina, e ambos são membros da subfamília Pyrrhulininae, caracterizados por apresentarem várias perdas ósseas e reduções relacionadas à complexidade da escultura dos seus esqueletos, principalmente em Copella e Pyrrhulina, quando comparados às espécies de Lebiasininae. Com base na análise filogenética e na observação da série ontogenética de vários representantes de Lebiasinidae, supõe-se que muitos traços morfológicos existentes em Pyrrhulininae tenham evoluído por meio do truncamento no desenvolvimento de characteres. A análise do material tipo de todas as espécies nominais e de uma grande quantidade de exemplares de Copella de diversas drenagens da América do Sul, indicou que seis de dez espécies nominais devem ser reconhecidas como válidas: Copella arnoldi, C. compta, C. eigenmanni, C. nattereri, C. stigmasemion, e C. vilmae. Copella arnoldi é sinônimo sênior de C. carsevennensis, C. eigenmanni arnoldi é sinônimo sênior de C. metae, C. nattereri é sinônimo sênior de C. callolepis e C. meinkeni, e C. stigmasemion, nova combinação, é sinônimo senior de C. nigrofasciata. Espécies de Copella ocorrem nas bacias dos rios Amazonas e Orinoco, e drenagens costeiras da Guiana, Guiana Francesa ...Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

FIGURE 1 in Moenkhausia goya (Characiformes: Characidae): a new species from the upper rio Tocantins basin, Central Brazil

FIGURE 1. Moenkhausia goya, holotype, MCP 51734, 60.5 mm SL, Brazil, Goiás, Pirenópolis, rio das Almas basin

Small Body, Large Chromosomes: Centric Fusions Shaped the Karyotype of the Amazonian Miniature Fish <i>Nannostomus anduzei</i> (Characiformes, Lebiasinidae)

Miniature refers to species with extraordinarily small adult body size when adult and can be found within all major metazoan groups. It is considered that miniature species have experienced severe alteration of numerous morphological traits during evolution. For a variety of reasons, including severe labor concerns during collecting, chromosomal acquisition, and taxonomic issues, miniature fishes are neglected and understudied. Since some available studies indicate possible relationship between diploid chromosome number (2n) and body size in fishes, we aimed to study one of the smallest Neotropical fish Nannostomus anduzei (Teleostei, Characiformes, Lebiasinidae), using both conventional (Giemsa staining, C-banding) and molecular cytogenetic methods (FISH mapping of rDNAs, microsatellites, and telomeric sequences). Our research revealed that N. anduzei possesses one of the lowest diploid chromosome numbers (2n = 22) among teleost fishes, and its karyotype is entirely composed of large metacentric chromosomes. All chromosomes, except for pair number 11, showed an 18S rDNA signal in the pericentromeric region. 5S rDNA signals were detected in the pericentromeric regions of chromosome pair number 1 and 6, displaying synteny to 18S rDNA signals. Interstitial telomeric sites (ITS) were identified in the centromeric region of pairs 6 and 8, indicating that centric fusions played a significant role in karyotype evolution of studied species. Our study provides further evidence supporting the trend of diploid chromosome number reduction along with miniaturization of adult body size in fishes