Identification of fish specimens of the Tocantins River, Brazil, using DNA barcoding.

The fish fauna of the Tocantins River possesses many endemic species; however, it is little studied in molecular terms and is quite threatened by the construction of several hydroelectric dams. Therefore, the objective of this study was to identify the ichthyofauna of the Tocantins River using DNA barcoding. For this, collections were carried out in five points of this river, which resulted in the capture of 725 individuals from which partial sequences of the cytochrome oxidase subunit I (COI) gene were obtained for genetic analysis. A total of 443 haplotypes were recovered with the mean intraspecific K2P genetic distance of 1.82%. Altogether, 138 species were identified based on morphological criteria, which was a quantity that was much lower than that indicated by the four molecular methods (assemble species by automatic partitioning [ASAP], barcode index number [BIN], generalized mixed Yule coalescent (GMYC), and Bayesian Poisson tree processes [bPTP]) through which 152-157 molecular entities were identified. In all, 41 unique BINs were obtained based on the data generated in the BOLDSystems platform. According to the result indicated by ASAP (species delimitation approach considered the most appropriate in the present study), there was an increase of 17 molecular entities (12.32%), when compared to the number of species identified through their morphological criteria, as it can show cryptic diversity, candidates for new species, and misidentifications. There were 21 incongruities indicated between the different identification approaches for species. Therefore, it is suggested that these taxonomic problems be cautiously evaluated by experts to solve such taxonomic issues.

Molecular Evidence Reveals Taxonomic Uncertainties and Cryptic Diversity in the Neotropical Catfish of the Genus Pimelodus (Siluriformes: Pimelodidae).

Pimelodus is the most speciose genus of the family Pimelodidae, and is amply distributed in the Neotropical region. The species-level taxonomy and phylogenetic relationships within this genus are still poorly resolved, however. These taxonomic problems and the general lack of data have generated major uncertainties with regard to the identification of specimens from different localities. In the present study, we applied a single-locus species delimitation approach to identify the MOTUs found within the genus Pimelodus and provide sound evidence for the evaluation of the species richness of this genus in the different river basins of the Neotropical region. The study was based on the analysis of sequences of the mitochondrial COI gene of 13 nominal species, which resulted in the identification of 24 consensus MOTUs. Only six nominal species were recovered as well-defined molecular entities by both the traditional barcoding analysis and the molecular delimitation methods, while the other seven presented cryptic diversity or persistent taxonomic uncertainties. The lineages identified from the Parnaíba ecoregions, Amazonas Estuary and Coastal Drainages may represent a much greater diversity of Pimelodus species than that recognized currently, although a more detailed study of this diversity will be necessary to provide a more definitive classification of the genus.

The DNA barcode reveals cryptic diversity and a new record for the genus Leporinus (Characiformes, Anostomidae) in the hydrographic basins of central northern Brazil.

Leporinus is one of the most speciose genera of the order Characiformes, with 81 valid species distributed throughout much of Central and South America. The considerable diversity of this genus has generated extensive debate on its classification and internal arrangement. In the present study, we investigated the species diversity of the genus Leporinus in central northern Brazil, and conclude that six valid species-Leporinus maculatus, Leporinus unitaeniatus, Leporinus affinis, Leporinus venerei, Leporinus cf. friderici, and Leporinus piau-are found in the hydrographic basins of the Brazilian states of Maranhão, Piauí, and Tocantins. We analyzed 182 sequences of the Cytochrome Oxidase subunit I gene, of which, 157 were obtained from Leporinus specimens collected from the basins of the Itapecuru, Mearim, Turiaçu, Pericumã, Periá, Preguiças, Parnaíba, and Tocantins rivers. The species delimitation analyses, based on the ABGD, ASAP, mPTP, bPTP, and GMYC methods, revealed the presence of four distinct molecular operational taxonomic units (MOTUs), identified as L. maculatus, L. unitaeniatus, L. affinis, and L. piau (from the Parnaíba River). The bPTP method restricted L. venerei to a single MOTU, and confirmed the occurrence of this species in the rivers of Maranhão for the first time. The separation of L. cf. friderici into two clades and the subsequent formation of different operational taxonomic units was consistent with polyphyly in this species, which indicates the existence of cryptic diversity. The arrangement of L. cf. friderici and L. piau in two different clades supports the conclusion that the L. piau specimens from Maranhão were misidentified, based on their morphological traits, reflecting the taxonomic inconsistencies that exist among morphologically similar species. Overall, then, the species delimitation methods employed in the present study indicated the presence of six MOTUs-L. maculatus, L. unitaenitus, L. affinis, L. cf. friderici, L. venerei, and L. piau. In the case of two other MOTUs identified in the present study, one (L. venerei) is a new record for the state of Maranhão, and we believe that the other represents a population of L. piau from the basin of the Parnaíba River.

Reconstrução das subunidades nasais após ressecção tumoral / Reconstruction of the nasal subunits after tumor resection

Introdução: A maioria dos defeitos nasais que se apresentam para reconstrução são secundários à excisão tumoral. O Objetivo é analisar a eficácia da técnica reconstrutora utilizada para a cobertura do defeito após exérese tumoral de acordo com a subunidade anatômica nasal acometida. Método: Estudo retrospectivo dos prontuários de 118 pacientes que durante o período de agosto de 2012 a março de 2017 foram submetidos à ressecção dos tumores nasais no Instituto Mário Penna em Belo Horizonte/MG. Resultados: A incidência foi maior em mulheres (56%) e brancos (54,3%) com idade média de 71,3 anos. Foram ressecados 125 tumores e realizadas 122 reconstruções nasais. O carcinoma basocelular (90,4%) foi o tumor de pele não melanoma mais prevalente, sendo o subtipo histológico sólido (33,6%) o mais frequente. As técnicas para reconstrução dos defeitos que acometiam apenas uma subunidade nasal foram em sua maioria utilizando o retalho bilobado (26,5%). Nas reconstruções nasais complexas, o retalho miocutâneo bilobado (45,8%) com extensão para a região glabelar (englobando os músculos prócero, corrugador e nasal) foi o mais utilizado, principalmente em defeitos no terço inferior do nariz. Cerca de 78 pacientes apresentaram acompanhamento oncológico superior a um ano, sendo avaliados 82 tumores no total. Sete (8,5%) tumores recidivaram mesmo após ressecção completa e, entre os seis pacientes com margens comprometidas, apenas um (1,2%) recidivou. Conclusão: As técnicas reconstrutoras utilizadas foram eficazes para o tratamento do câncer de pele nasal e cobertura dos defeitos após ressecção, apresentando baixos índices de complicação e recidiva.

Introduction: A majority of the nods present for reconstruction are secondary to tumor excision. The objective is to analyze the efficacy of the reconstructive technique used to cover the defect after tumor exeresis according to the affected nasal anatomical subunit. Method: Retrospective study of the medical records of 118 patients submitted to resection of the nasal tumors at the Mário Penna Institute in Belo Horizonte/ MG from August 2012 to March 2017. Results: Incidence was higher in women (56%) and whites (54.3%) average age of 71.3 years. A total of 125 tumors were resected, and 122 nose reconstructions were performed. Basal cell carcinoma (90.4%) was the most prevalent nonmelanoma skin tumor, the most frequent solid histological subtype (33.6%). The techniques for reconstruction of defects that affect only one nasal subunit were mostly using the bilobed flap (26.5%). In complex nose reconstructions, the bilobed myocutaneous flap (45.8%) with extension to a glabella region (encompassing the procerus, corrugator and nasal muscles) was the most used, mainly in defects in the lower third of the nose. About 78 patients had cancer follow-up of more than one year, and 82 total sin tumors were evaluated. Seven (8.5%) Tumors retreated even after complete resection, and, among the six patients with compromised margins, only one (1.2%) relapsed. Conclusion: The reconstructive techniques used were effective for treating nasal skin cancer and coverage of defects after resection, with low rates of complication and recurrence.

Divertículo traqueal: um relato de caso e revisão da literatura / Tracheal diverticulum: a case report and literature review

Divertículo traqueal é uma patologia benigna caracterizada por invaginações únicas ou múltiplas na parede da traqueia. Condição rara, com poucos casos relatados na literatura mundial. Tem etiologias congênita ou adquirida. A maioria dos pacientes são completamente assintomáticos durante toda a sua vida, o que justifica um pequeno número de casos na literatura. O diagnóstico é feito por Tomografia Computadorizada (preferencialmente helicoidal) de pescoço. O caso relato é de uma mulher de 55 anos, portadora de asma brônquica de difícil controle atendida no ambulatório de cirurgia torácica de um hospital público brasileiro com quadro de tosse crônica e dispneia intermitentes há cerca de dois anos. Propedêutica com broncoscopia e endoscopia digestiva alta sem achados anormais. Tomografia computadorizada de pescoço multislice detectou formação cística de conteúdo aéreo projetada para a direita da traqueia. Submetida a cervicotomia exploradora e ressecção de formação cística, ovóide, posterior ao lobo direito da tireóide, com comunicação com a traquéia. Estudo histopatológico evidenciou lesão constituída de epitélio respiratório, achado que corroborou o diagnóstico de divertículo traqueal. Essa patologia foi identificada como de causa adquirida no caso relatado, devido ao quadro de tosse crônica pela asma brônquica de difícil controle, achados compatíveis com a literatura mundial. (AU)

Tracheal diverticulum is a benign pathology characterized by single or multiple invaginations in the trachea wall. It is a rare condition, with few cases reported in the world literature. Tracheal diverticulum can be either congenital or acquired. Most patients are completely asymptomatic throughout the life, which justifies a small number of cases reported in the literature. The diagnosis is made by computed tomography multi-slice of the neck. The case report is of a asthmatic 55-year-old female, with a 2-year history of repeatedly cough and dyspnea met in thoracic surgery clinic of a brazilian public hospital. Workup with bronchoscopy and endoscopy with no abnormal findings. Computed tomography multi-slice detected a paratracheal air cyst located at the right posterolateral aspect of the trachea. The patient underwent exploratory cervicotomy and resection of a cystic lesion, ovoid, posterior the right lobe of the thyroid, with communication with the trachea. The final pathological report: respiratory epithelium in the cyst wall, a finding that corroborates the diagnosis of tracheal diverticulum. In the case reported, the tracheal diverticulum was determined as acquired, due to chronic cough by asthma, findings consistent with the literature. (AU)