A phylogenetic analysis of Brycon and Henochilus (Characiformes, Characidae, Bryconinae) based on the mitochondrial gene 16S rRNA

The genus Brycon, the largest subunit of the Bryconinae, has 42 valid species distributed from southern Mexico to the La Plata River in Argentina. Henochilus is a monotypic genus, comprising a single species (H. wheatlandii) found in the upper Rio Doce basin. In the present study, partial sequences of the mitochondrial gene 16S were obtained for fifteen species of Brycon and for Henochilus wheatlandii. The results showed that the genus Brycon is paraphyletic, since Henochilus is the sister-group of B. ferox and B. insignis. The most basal species analyzed were the trans-Andean species B. henni, B. petrosus, and B. chagrensis.

Supressão das anomalias de fase e batimentos laterais em espectros de RMN 13c obtidos com a sequência de precessão livre no estado estacionário

The Steady-State Free Precession (SSFP) sequence has been widely used in low-field and low-resolution imaging NMR experiments to increase the signal-to-noise ratio (s/n) of the signals. Here, we analyzed the Scrambled Steady State - SSS and Unscrambled Steady State - USS sequences to suppress phase anomalies and sidebands of the 13C NMR spectrum acquired in the SSFP regime. The results showed that the application of the USS sequence allowed a uniform distribution of the time interval between pulses (Tp), in the established time range, allowing a greater suppression of phase anomalies and sidebands, when compared with the SSS sequence.

Identificação de operantes verbais constituintes da leitura por meio da análise dos movimentos dos olhos

Os movimentos dos olhos produzem estímulos discriminativos para o comportamento de ler. O presente estudo teve por objetivo analisar os movimentos dos olhos de dois participantes durante a leitura de anagramas e identificar os operantes verbais envolvidos. A tarefa consistia em vocalizar uma palavra utilizando cinco letras. Na Fase 1, as letras formavam apenas uma palavra, sempre que observadas em uma mesma sequência espacial. Na Fase 2, formavam duas ou mais a partir de diferentes sequências. Na Fase 2, apesar da possibilidade de múltipla formação de palavras, as palavras vocalizadas foram aquelas formadas pela mesma sequência reforçada na fase anterior. Com base nos movimentos dos olhos, as vocalizações foram analisadas à luz dos conceitos de comportamento textual, auto-correção e intraverbal.

Obtenção e caracterização de α-quitina e quitosanas de cascas de Macrobrachium rosembergii

The shells of Macrobrachium rosenbergii were submitted to deproteinization (Dp) and demineralization (Dm) aiming the extraction of α-chitin. The different parts of the shells were processed independently by carrying out sequence 1 (Dp/Dm) and sequence 2 (Dm/Dp). Both sequences allowed the extraction of chitins with low contents of calcium and magnesium, regardless of the part being processed. The sequence 1 lead to higher extraction yields while sequence 2 resulted in lower contents of inorganic compounds. Extensively deacetylated chitosans (GA<10%) of medium molecular weight (0,9 x 10(5) < Mv < 2 x 10(5) g/mol) resulted from the deacetylation of chitin.

Antibiosis and dark-pigments secretion by the phytopathogenic and environmental fungal species after interaction in vitro with a Bacillus subtilis isolate

In this work, different reactions in vitro between an environmental bacterial isolate and fungal species were related. The Gram-positive bacteria had terminal and subterminal endospores, presented metabolic characteristics of mesophilic and acidophilic growth, halotolerance, positive to nitrate reduction and enzyme production, as caseinase and catalase. The analysis of partial sequences containing 400 to 700 bases of the 16S ribosomal RNA gene showed identity with the genus Bacillus. However, its identity as B. subtilis was confirmed after analyses of the rpoB, gyrA, and 16S rRNA near-full-length sequences. Strong inhibitory activity of environmental microorganisms, such as Penicillium sp, Aspergillus flavus, A. niger, and phytopathogens, such as Colletotrichum sp, Alternaria alternata, Fusarium solani and F. oxysporum f.sp vasinfectum, was shown on co-cultures with B. subtilis strain, particularly on Sabouraud dextrose agar (SDA) and DNase media. Red and red-ochre color pigments, probably phaeomelanins, were secreted by A. alternata and A. niger respectively after seven days of co-culture.

Analysis of mangrove forest succession, using sediment cores: a case study in the Cananéia -Iguape coastal system, São Paulo Brazil

Sediment cores are an essential tool for the analysis of the dynamics of mangrove succession. Coring was used to correlate changes in depositional environments and lateral sedimentary facies with discrete stages of forest succession at the Cananéia-Iguape Coastal System in southeastern Brazil. A local level successional pattern was examined based on four core series T1) a sediment bank; T2) a smooth cordgrass Spartina alterniflora bank; T3) an active mangrove progradation fringe dominated by Laguncularia racemosa, and; T4) a mature mangrove forest dominated by Avicennia schaueriana. Cores were macroscopically described in terms of color, texture, sedimentary structure and organic components. The base of all cores exhibited a similar pattern suggesting common vertical progressive changes in depositional conditions and subsequent successional colonization pattern throughout the forest. The progradation zone is an exposed bank, colonized by S. alterniflora. L. racemosa, replaces S. alterniflora as progradation takes place. As the substrate consolidates A. schaueriana replaces L. racemosa and attains the greatest structural development in the mature forest. Cores collected within the A. schaueriana dominated stand contained S. alterniflora fragments near the base, confirming that a smooth cordgrass habitat characterized the establishment and early seral stages. Cores provide a reliable approach to describe local-level successional sequences in dynamic settings subject to drivers operating on multiple temporal and spatial scales where spatial heterogeneity can lead to multiple equilibria and where similar successional end-points may be reached through convergent paths.

Molecular phylogeny of advanced snakes (Serpentes, Caenophidia) with an emphasis on South American Xenodontines: a revised classification and descriptions of new taxa

We present a molecular phylogenetic analysis of caenophidian (advanced) snakes using sequences from two mitochondrial genes (12S and 16S rRNA) and one nuclear (c-mos) gene (1681 total base pairs), and with 131 terminal taxa sampled from throughout all major caenophidian lineages but focussing on Neotropical xenodontines. Direct optimization parsimony analysis resulted in a well-resolved phylogenetic tree, which corroborates some clades identified in previous analyses and suggests new hypotheses for the composition and relationships of others. The major salient points of our analysis are: (1) placement of Acrochordus, Xenodermatids, and Pareatids as successive outgroups to all remaining caenophidians (including viperids, elapids, atractaspidids, and all other "colubrid" groups); (2) within the latter group, viperids and homalopsids are sucessive sister clades to all remaining snakes; (3) the following monophyletic clades within crown group caenophidians: Afro-Asian psammophiids (including Mimophis from Madagascar), Elapidae (including hydrophiines but excluding Homoroselaps), Pseudoxyrhophiinae, Colubrinae, Natricinae, Dipsadinae, and Xenodontinae. Homoroselaps is associated with atractaspidids. Our analysis suggests some taxonomic changes within xenodontines, including new taxonomy for Alsophis elegans, Liophis amarali, and further taxonomic changes within Xenodontini and the West Indian radiation of xenodontines. Based on our molecular analysis, we present a revised classification for caenophidians and provide morphological diagnoses for many of the included clades; we also highlight groups where much more work is needed. We name as new two higher taxonomic clades within Caenophidia, one new subfamily within Dipsadidae, and, within Xenodontinae five new tribes, six new genera and two resurrected genera. We synonymize Xenoxybelis and Pseudablabes with Philodryas; Erythrolamprus with Liophis; and Lystrophis and Waglerophis with Xenodon.

Cytogenetic analysis of Astylus antis (Perty, 1830) (Coleoptera, Melyridae): Karyotype, heterochromatin and location of ribosomal genes

Cytogenetic analysis of Astylus antis using mitotic and meiotic cells was performed to characterize the haploid and diploid numbers, sex determination system, chromosome morphology, constitutive heterochromatin distribution pattern and chromosomes carrying nucleolus organizer regions (NORs). Analysis of spermatogonial metaphase cells revealed the diploid number 2n = 18, with mostly metacentric chromosomes. Metaphase I cells exhibited 2n = 8II+Xyp and a parachute configuration of the sex chromosomes. Spermatogonial metaphase cells submitted to C-banding showed the presence of small dots of constitutive heterochromatin in the centromeric regions of nearly all the autosomes and on the short arm of the X chromosome (Xp), as well as an additional band on one of the arms of pair 1. Mitotic cells submitted to double staining with base-specific fluorochromes (DAPI-CMA3) revealed no regions rich in A+T or G+C sequences. Analysis of spermatogonial mitotic cells after sequential Giemsa/AgNO3 staining did not reveal any specific mark on the chromosomes. Meiotic metaphase I cells stained with silver nitrate revealed a strong impregnation associated to the sex chromosomes, and in situ hybridization with an 18S rDNA probe showed ribosomal cistrons in an autosomal bivalent.

Análise das relações taxonômicas e sistemáticas entre espécies de triatomíneos (Hemiptera, Reduviidae) de colônias mantidas pelo Serviço Especial de Saúde de Araraquara, inferida de seqüências do 16S rDNA mitocondrial

Foram analisadas seqüências de nucleotídeos do gene 16S do rDNA mitocondrial em 14 populações de triatomíneos mantidos em colônias no insetário SESA de Araraquara- SP, comparando-as com seqüências do mesmo gene disponíveis no GenBank. Os fragmentos variaram de 311 a 317 pb com baixa variação intra-específica entre as distâncias genéticas (0% a 0,6%), exceto para os relacionamentos entre espécimes de Triatoma sordida (1%) e espécimes de T. brasiliensis (1,3%) atribuídos a populações geográficas diferentes. A parafilia de Rhodniini e do gênero Panstrongylus foi evidenciada pelas analises, confirmando resultados anteriores entre estes e os estreitos relacionamentos de R. prolixus com R. robustus e de T. infestans e T. platensis. O relacionamento entre T. maculata e T. pseudomaculata não foi solucionado, uma vez que, esses táxons apareceram tanto em monofilia quanto em parafilia: T. pseudomaculata (SESA) está agrupado com T. maculata (seqüência do GenBank) e associados a T . brasiliensis (SESA), enquanto T. maculata (SESA) aparece agrupado com T. pseudomaculata do SESA e do GenBank. Os resultados evidenciam a utilidade do gene 16S como marcador de espécies de triatomíneos e sua importância em questões de sistemática e taxonomia. Há necessidade de novos estudos envolvendo outros marcadores associados a caracteres sistemáticos clássicos de morfologia, ecologia e comportamento para decisões sistemáticas adequadas uma vez, que teriam impacto não apenas sistemático mas, para as estratégias de controle.

Anopheles (Nyssorhynchus) atacamensis (Diptera: Culicidae), a new species from Northern Chile

Anopheles (Nyssorhynchus) atacamensis, a new species in the subgenus Nyssorhynchus, is described and validated using morphological characters of the male and female adult, male genitalia and immature stages. Molecular characterization employing sequences of the ITS2 rDNA and COI mtDNA are provided. The new taxon is compared with Anopheles (Nyssorhynchus) pictipennis (Philippi) from central Chile based on morphological features of the adults, male genitalia and larva. Illustrations of the diagnostic characteristics of the male genitalia, fourth-instar larva and pupa are provided.

Imagem por ressonância magnética na investigação da cabeça de cães

A imagem por ressonância magnética (IRM) é o método de diagnóstico por imagem não invasivo mais sensível para avaliar as partes moles, particularmente o encéfalo, porém trata-se de uma técnica onerosa. O método fundamenta-se no fenômeno da ressonância magnética nuclear que ocorre quando núcleos atômicos com propriedades magnéticas presentes no corpo são submetidos a um campo magnético intenso, sendo posteriormente excitados por energia de radiofrequência e gerando, por sua vez, um sinal de onda de radiofrequência capaz de ser captado por uma antena receptora, passando por um processo matemático, chamado Transformada de Fourier, para posterior formação da imagem. Esse estudo objetivou realizar 10 exames completos da cabeça em cadáveres de cães normais à IRM e confeccionar um Atlas com as estruturas identificadas. As imagens foram adquiridas em um aparelho de ressonância magnética Gyroscan S15/HP Philips com campo magnético de 1,5Tesla. Os cadáveres foram posicionados com a cabeça no interior de uma bobina de cabeça humana e foram submetidos a cortes iniciais sagitais a partir de onde se planejou os cortes transversais e dorsais nas sequências de pulso spin-eco T1, T2 e DP. Em T1 utilizou-se TR=400ms e TE=30ms, T2 utilizou-se TR=2000ms e TE=80ms e na DP utilizou-se TR=2000ms e TE=30ms. A espessura do corte foi de 4mm, o número de médias foi igual a 2, a matriz foi de 256x256, o fator foi igual a 1,0 e o campo de visão foi de 14cm. A duração do exame completo da cabeça foi de 74,5minutos. As imagens obtidas com as sequências utilizadas e com a bobina de cabeça humana foram de boa qualidade. Em T1 a gordura tornou-se hiperintensa e o líquido hipointenso. Em T2 a gordura ficou menos hiperintensa e o líquido hiperintenso. A cortical óssea e o ar foram hipointensos em todas as sequências utilizadas devido a baixa densidade de prótons. A sequência DP mostrou o melhor contraste entre a substância branca e cinzenta quando comparada a T2 e a T1. T2 evidenciou o líquido cefalorraquidiano tornando possível a distinção dos sulcos e giros cerebrais. Através do exame de IRM foi possível, pelo contraste, identificar as estruturas ósseas componentes da arquitetura da região, músculos, grandes vasos venosos e arteriais e estruturas do sistema nervoso central, além de elementos do sistema digestório, respiratório e estruturas dos olhos entre outras. Nesse estudo as IRM adquiridas nas sequências T1, DP e T2 foram complementares para o estudo dos aspectos anatômicos da cabeça de cães demonstrando-os com riqueza de detalhes. O tempo requerido para o exame completo da cabeça é compátivel para uso em animais vivos desde que devidamente anestesiados e controlados. Os resultados obtidos por esse trabalho abrem caminho em nosso meio, para o estudo de animais vivos e para o início da investigação de doenças, principalmente as de origem neurológica, visto ser esta técnica excelente para a visibilização do encéfalo.

Occurrence and molecular characterization of Cryptosporidium spp. isolated from domestic animals in a rural area surrounding Atlantic dry forest fragments in Teodoro Sampaio municipality, State of São Paulo, Brazil

The aim of this study was to assess the occurrence of Cryptosporidium in domestic animals in rural properties surrounding rain forest fragments within the municipality of Teodoro Sampaio, southeastern Brazil. Conventional sucrose flotation method followed by molecular characterization of the parasites by sequencing PCR products amplified from SSU rRNA gene were used. Stool samples were collected from domestic animals raised as pets and livestock in all rural properties surrounding three forest fragments. Samples from cattle (197), equine (63), pigs (25), sheep (11), and dogs (28) were collected from 98 rural properties. The frequency of occurrence of Cryptosporidium within each animal species was 3.0% (6/197) among cattle and 10.7% (3/28) among dogs. Cryptosporidium was not detected in stool samples from equine, sheep, and pigs. All sequences obtained from the six samples of calves showed molecular identity with Cryptosporidium andersoni while all sequences from dog samples were similar to C. canis. The frequency of occurrence of Cryptosporidium in these domestic animal species was low. The absence of C. parvum in the present study suggests that the zoonotic cycle of cryptosporidiosis may not be relevant in the region studied. The presence of Cryptosporidium species seldom described in humans may be, otherwise, important for the wild fauna as these animals are a source of infection and dissemination of this protozoan to other animal species. The impact and magnitude of infection by C. andersoni in wild ruminants and C. canis in wild canids have to be assessed in future studies to better understand the actual importance of these species in this region.

Rapid detection of bovine coronavirus by a semi-nested RT-PCR

Bovine coronavirus (BCoV) is a member of the group 2 of the Coronavirus (Nidovirales: Coronaviridae) and the causative agent of enteritis in both calves and adult bovine, as well as respiratory disease in calves. The present study aimed to develop a semi-nested RT-PCR for the detection of BCoV based on representative up-to-date sequences of the nucleocapsid gene, a conserved region of coronavirus genome. Three primers were designed, the first round with a 463bp and the second (semi-nested) with a 306bp predicted fragment. The analytical sensitivity was determined by 10-fold serial dilutions of the BCoV Kakegawa strain (HA titre: 256) in DEPC treated ultra-pure water, in fetal bovine serum (FBS) and in a BCoV-free fecal suspension, when positive results were found up to the 10-2, 10-3 and 10-7 dilutions, respectively, which suggests that the total amount of RNA in the sample influence the precipitation of pellets by the method of extraction used. When fecal samples was used, a large quantity of total RNA serves as carrier of BCoV RNA, demonstrating a high analytical sensitivity and lack of possible substances inhibiting the PCR. The final semi-nested RT-PCR protocol was applied to 25 fecal samples from adult cows, previously tested by a nested RT-PCR RdRp used as a reference test, resulting in 20 and 17 positives for the first and second tests, respectively, and a substantial agreement was found by kappa statistics (0.694). The high sensitivity and specificity of the new proposed method and the fact that primers were designed based on current BCoV sequences give basis to a more accurate diagnosis of BCoV-caused diseases, as well as to further insights on protocols for the detection of other Coronavirus representatives of both Animal and Public Health importance.

Caracterização molecular do vírus da raiva isolado de Desmodus rotundus capturados no Estado do Rio de Janeiro

Caracterizou-se filogeneticamente o vírus da raiva, isolado de morcegos hematógafos (Demodus rotundus). Cento e noventa e nove D. rotundus foram capturados em cinco abrigos, no Norte e Noroeste do Estado do Rio de Janeiro e sul do Espírito Santo. Sete deles foram positivos para a raiva. Amostras desses vírus foram sequenciadas e comparadas com sequências provenientes de diversos estados brasileiros. As sequências de vírus da raiva isoladas, na região norte do Estado do Rio de Janeiro, mostraram características que as distinguem de amostras de vírus isoladas em outras regiões do país, no entanto foram idênticas às isoladas de bovinos no noroeste do Rio de Janeiro.

Resurrection of Anopheles goeldii from synonymy with Anopheles nuneztovari (Diptera, Culicidae) and a new record for Anopheles dunhami in the Brazilian Amazon

Nucleotide sequences of the internal transcribed spacer 2 (ITS2) rDNA and partial sequences of the cytochrome coxidase subunit I (COI) mtDNA and white gene nDNA were obtained from specimens of Anopheles nuneztovari A collected in Macapá (state of Amapá), Óbidos, Prainha and Almeirim (state of Pará), Itacoatiara and Parintins (state of Amazonas), Brazil, and compared with previously published sequences of A. nuneztovari s.l. Results of the Bayesian phylogenetic analyses performed using either COI or combined ITS2, COI and white gene sequences suggest that An. nuneztovari B/C is distinct from specimens obtained in the Amazonas/Solimões River basin. Anopheles goeldii, currently in synonymy with An. nuneztovari, was described from individuals collected in Belterra (= Fordlândia) in the Tapajós River, state of Pará, Southern Amazonas River. Morphological comparisons of the characteristics of the male genitalia indicated that An. nuneztovari A and An. goeldii are similar but distinct from An. nuneztovariB/C by the apex of the aedeagus. In considering the results of the phylogenetic analyses and morphological comparisons, An. goeldii is resurrected from synonymy with An. nuneztovari. Additionally, Anopheles dunhamiis reported for the first time in Parintins. This species can be distinguished from An. goeldiiby characters of the male genitalia and molecular data