Comparative cytogenetics of Serrasalmidae (Teleostei: Characiformes): The relationship between chromosomal evolution and molecular phylogenies.

Serrasalmidae has high morphological and chromosomal diversity. Based on molecular hypotheses, the family is currently divided into two subfamilies, Colossomatinae and Serrasalminae, with Serrasalminae composed of two tribes: Myleini (comprising most of pacus species) and Serrasalmini (represented by Metynnis, Catoprion, and remaining piranha's genera). This study aimed to analyze species of the tribes Myleini (Myloplus asterias, M. lobatus, M. rubripinnis, M. schomburgki, and Tometes camunani) and Serrasalmini (Metynnis cuiaba, M. hypsauchen, and M. longipinnis) using classical and molecular cytogenetic techniques in order to understand the chromosomal evolution of the family. The four species of the genus Myloplus and T. camunani presented 2n = 58 chromosomes, while the species of Metynnis presented 2n = 62 chromosomes. The distribution of heterochromatin occurred predominantly in pericentromeric regions in all species. Tometes camunani and Myloplus spp. presented only one site with 5S rDNA. Multiple markers of 18S rDNA were observed in T. camunani, M. asterias, M. lobatus, M. rubripinnis, and M. schomburgkii. For Metynnis, however, synteny of the 18S and 5S rDNA was observed in the three species, in addition to an additional 5S marker in M. longipinnis. These data, when superimposed on the phylogeny of the family, suggest a tendency to increase the diploid chromosome number from 54 to 62 chromosomes, which occurred in a nonlinear manner and is the result of several chromosomal rearrangements. In addition, the different karyotype formulas and locations of ribosomal sequences can be used as cytotaxonomic markers and assist in the identification of species.

Análise molecular revela alta diversidade no complexo de espécies Hoplias malabaricus (Characiformes, Erythrinidae) de diferentes localidades amazônicas / Molecular analysis reveals high diversity in the Hoplias malabaricus (Characiformes, Erythrinidae) species complex from different Amazonian localities

O DNA barcoding propõe que um fragmento de DNA possa servir para identificar espécies. Em peixes, um fragmento do gene COI tem se mostrado eficaz em muitos estudos com focos diferentes. Nós usamos essa ferramenta molecular para fornecer novas informações sobre a diversidade críptica encontrada no complexo de espécies Hoplias malabaricus. Popularmente conhecida como traíra, H. malabaricus tem uma ampla distribuição na América do Sul. Esse clado mostra diversidade molecular e citogenética, e vários estudos dão suporte à ocorrência de um complexo de espécies. Realizamos análises molecular e cariotípica em indivíduos de H. malabaricus de oito localidades amazônicas, para acessar a diversidade no taxon nominal e elucidar as relações nesse grupo. Usamos 12 amostras em análises citogenéticas e encontramos dois cariomorfos: 2n = 40 (20m + 20sm) (cariomorfo C) e 2n = 42 (22m + 20sm) (cariomorfo A). Usamos 19 amostras em análise molecular, utilizando COI como marcador molecular, análises de máxima verossimilhança e o modelo evolutivo de Kimura-2-parâmetros com estimativa de bootstrap. Encontramos diferenciação relacionada aos cariomorfos com bootstrap de 100%. No entanto, encontramos alta diversidade molecular no cariomorfo C. O padrão observado nos permitiu inferir a presença de diversidade oculta, reforçando a existência de um complexo de espécies. (AU)

Molecular analysis reveals high diversity in the Hoplias malabaricus (Characiformes, Erythrinidae) species complex from different Amazonian localities

ABSTRACT DNA barcoding proposes that a fragment of DNA can be used to identify species. In fish, a fragment of cytochrome oxidase subunit I (COI) has been effective in many studies with different foci. Here we use this molecular tool to provide new insights into the cryptic diversity found in the Hoplias malabaricus species complex. Popularly known as trahira, H. malabaricus is widely distributed in South America. The clade shows molecular and cytogenetic diversity, and several studies have supported the occurrence of a complex of species. We performed molecular and karyotypic analysis of H. malabaricus individuals from eight Amazonian localities to assess the diversity present in the nominal taxon, and to clarify relationships within this group. We used 12 samples in cytogenetic analyses and found two karyomorphs: 2n = 40 (20m + 20sm) (karyomorph C) and 2n = 42 (22m + 20sm) (karyomorph A). We used 19 samples in molecular analyses with COI as a molecular marker, maximum likelihood analyses, and the Kimura-2-parameter evolutionary model with bootstrap support. We found karyomorph-related differentiation with bootstrap of 100%. However, we found high molecular diversity within karyomorph C. The observed pattern allowed us to infer the presence of cryptic diversity, reinforcing the existence of a species complex.

RESUMO O DNA barcoding propõe que um fragmento de DNA possa servir para identificar espécies. Em peixes, um fragmento do gene COI tem se mostrado eficaz em muitos estudos com focos diferentes. Nós usamos essa ferramenta molecular para fornecer novas informações sobre a diversidade críptica encontrada no complexo de espécies Hoplias malabaricus. Popularmente conhecida como traíra, H. malabaricus tem uma ampla distribuição na América do Sul. Esse clado mostra diversidade molecular e citogenética, e vários estudos dão suporte à ocorrência de um complexo de espécies. Realizamos análises molecular e cariotípica em indivíduos de H. malabaricus de oito localidades amazônicas, para acessar a diversidade no taxon nominal e elucidar as relações nesse grupo. Usamos 12 amostras em análises citogenéticas e encontramos dois cariomorfos: 2n = 40 (20m + 20sm) (cariomorfo C) e 2n = 42 (22m + 20sm) (cariomorfo A). Usamos 19 amostras em análise molecular, utilizando COI como marcador molecular, análises de máxima verossimilhança e o modelo evolutivo de Kimura-2-parâmetros com estimativa de bootstrap. Encontramos diferenciação relacionada aos cariomorfos com bootstrap de 100%. No entanto, encontramos alta diversidade molecular no cariomorfo C. O padrão observado nos permitiu inferir a presença de diversidade oculta, reforçando a existência de um complexo de espécies.

Conhecimento dos pacientes diabéticos usuários do Sistema Único de Saúde acerca da retinopatia diabética / Knowledge of diabetic patients users of the Health Unic System about diabetic retinopathy

Resumo Objetivo: Avaliar o nível de conhecimento dos pacientes diabéticos, atendidos no Sistema Único de Saúde (SUS) na cidade de Boa Vista/Roraima, acerca da Retinopatia Diabética (RD). Métodos: Trata-se de um estudo transversal, descritivo, de caráter quantitativo, realizado através da aplicação de um questionário semi-estruturado para 150 indivíduos diabéticos, usuários do SUS, da cidade de Boa Vista - RR, durante o ano de 2017. As análises estatísticas foram realizadas utilizando os programas Microsoft Excel e EpiInfo 7®, fixando-se o nível de 5% para a rejeição da hipótese de nulidade. Resultados: Do total amostral pesquisado,76,7% dos indivíduos não possuía nenhum conhecimento sobre a RD, 19,3% tinha algum tipo de conhecimento, mas não possuía a patologia, 2,7% conhecia, possuía a RD e fazia tratamento e 1,3% conhecia, possuía a RD e não se tratava. Quanto a orientação, 40,6% dos participantes nunca recebeu nenhuma informação sobre o risco de perda da visão. Acerca do tipo de Diabetes, 44,7% dos participantes não sabia que tipo possuía, 42% relatou ter DM 2 e 13,3% DM1. Sobre o controle da glicose, 59,4% não conseguia mantê-lo. Foi evidenciada associação entre o controle da glicose e o conhecimento sobre RD, entre o tempo de instalação da DM e o conhecimento sobre RD e entre ter consultado um oftalmologista e conhecer sobre a RD. Conclusão: O nível de conhecimento sobre a RD é muito baixo, fator preocupante por tratar-se de uma das complicações mais importantes do Diabetes. Percebe-se que o sistema de saúde não está sendo eficiente como facilitador deste conhecimento.

Abstract Objective: To evaluate the level of knowledge of diabetic patients treated at the Unified Health System (SUS - Sistema Único de Saúde) in the city of Boa Vista / Roraima, about Diabetic Retinopathy (DR). Methods: This is a cross-sectional, descriptive, quantitative study conducted through the application of a semi-structured questionnaire for 150 diabetic individuals, SUS users, from the city of Boa Vista - RR, during the year 2017. Statistical analyzes were performed using the Microsoft Excel and EpiInfo 7® programs, setting the 5% level for the rejection of the null hypothesis. Results: Of the total sample, 76.7% of the individuals did not have any knowledge about DR, 19.3% had some type of knowledge, but did not have the pathology, 2.7% knew, had DR and was receiving treatment, 1,3% knew, had DR and was not receiving treatment. About orientation, 40.6% of the participants never received any information about the risk of vision loss. About the type of Diabetes, 44.7% of the participants did not know what type they had, 42% reported having DM 2 and 13.3% DM1. On glucose control, 59.4% could not maintain it. It was evidenced an association between glucose control and DR knowledge, between the time of DM installation and knowledge about DR, and between having consulted an ophthalmologist and knowing about DR. Conclusion: The level of knowledge about DR is very low, a worrying factor because it is one of the most important complications of diabetes. It is observed that the health system is not being efficient as facilitator of this knowledge.

Chromosomal Mapping of Repetitive Sequences (Rex3, Rex6, and rDNA Genes) in Hybrids Between Colossoma macropomum (Cuvier, 1818) and Piaractus mesopotamicus (Holmberg, 1887).

Some species of Characiformes are known for their high economic value, such as Colossoma macropomum and Piaractus mesopotamicus, and are used in aquaculture programs to generate hybrid tambacu (interbreeding of C. macropomum females and P. mesopotamicus males). The present work aimed to investigate the location of the Rex3 and Rex6 transposable elements in the hybrid and in the species, in addition to checking the genomic organization of the 18S and 5S rDNA in tambacu. The diploid number found for the hybrid was equal to 54 chromosomes, with heterochromatic blocks distributed mainly in the centromeric portions. The chromosomal location of the mobile elements Rex3 and Rex6 in C. macropomum, P. mesopotamicus, and in the hybrid between these species enabled knowledge expansion and the generation of data on such mobile elements. In addition, the location of such elements is not related to the distribution of ribosomal DNA sites. The mapping of the 18S rDNA was shown to be effective in cytogenetic identification of the hybrid tambacu, allowing for differentiation from the parent species and from the hybrid between C. macropomum and the other species from Piaractus (P. brachypomus).

Chromosomal Mapping of Transposable Elements of the Rex Family in the Bristlenose Catfish, Ancistrus (Siluriformes, Loricariidae), from the Amazonian Region.

Repetitive DNA sequences are present in the genome of basically every known organism, and transposable elements (TE) are one of the most representative sequences involved in chromosomal rearrangements and the genomic evolution of eukaryotes. In fish, the non-LTR retrotransposon TEs, Rex1, Rex3, and Rex6, are widely distributed in fish genomes and are the best-characterized TEs in several species. In the current study, three of these retroelements were physically mapped, through fluorescent in situ hybridization (FISH), in 7 species (71 specimens) of the genus Ancistrus, known as bristlenose catfish: Ancistrus ranunculus, Ancistrus sp. 1 "Purus," Ancistrus sp. 2 "Catalão," Ancistrus dolichopterus, Ancistrus maximus, Ancistrus aff. dolichopterus, and Ancistrus dubius. Rex1, Rex3, and Rex6 showed a cluster distribution, mainly in the terminal and pericentromeric portions, in heterochromatic and euchromatic regions, and did not occur in sexual chromosomes; however, the number and position of the clusters varied between species. This TE distribution suggests its implication in the karyotypic evolution of these species, without affecting the rise of sexual chromosome systems in Ancistrus, in view of their chromosomal variation.

First Cytogenetic Description of Microsternarchus bilineatus (Gymnotiformes: Hypopomidae) from Negro River (Brazilian Amazon).

Microsternarchus bilineatus is a neotropical electric fish species widely distributed in Amazonian ecosystems. This work reports the first karyotypic description of the species M. bilineatus, which presented 2n = 48 chromosomes, with a distinct karyotypic formula between the sexes: males with 21 metacentric (m)/submetacentric (sm) + 27 subtelocentric (st)/acrocentric (a) and fundamental number (FN) = 69 and females with 20 m/sm + 28 st/a and FN = 68. We found a probable recent sex system of XX/XY type. The nucleoli organizer regions (NORs) were multiple terminally located, and the heterochromatic blocks were mostly pericentromeric. The 18S rDNA markings confirmed NORs and their distinction between sexes, which suggested some differential role of this gene related to gender in this species. The 5S rDNA presented terminal markings on a single chromosome pair, with no distinction between sexes, and the telomeric probes have shown a uniform pattern in males and females.

Chromosome mapping of repetitive sequences in four Serrasalmidae species (Characiformes).

The Serrasalmidae family is composed of a number of commercially interesting species, mainly in the Amazon region where most of these fishes occur. In the present study, we investigated the genomic organization of the 18S and 5S rDNA and telomeric sequences in mitotic chromosomes of four species from the basal clade of the Serrasalmidae family: Colossoma macropomum, Mylossoma aureum, M. duriventre, and Piaractus mesopotamicus, in order to understand the chromosomal evolution in the family. All the species studied had diploid numbers 2n = 54 and exclusively biarmed chromosomes, but variations of the karyotypic formulas were observed. C-banding resulted in similar patterns among the analyzed species, with heterochromatic blocks mainly present in centromeric regions. The 18S rDNA mapping of C. macropomum and P. mesopotamicus revealed multiple sites of this gene; 5S rDNA sites were detected in two chromosome pairs in all species, although not all of them were homeologs. Hybridization with a telomeric probe revealed signals in the terminal portions of chromosomes in all the species and an interstitial signal was observed in one pair of C. macropomum.