A cave population of Isbrueckerichthys alipionis (Gosline, 1947) in the Upper Ribeira karst area, southeastern Brazil (Siluriformes: Loricariidae)

A cave population of the armored catfish Isbrueckerichthys alipionis is reported from the Santana Cave, in the rio Betari watershed, Upper Ribeira karst area, Iporanga, São Paulo State, southeastern Brazil. The cave population was compared to an epigean population of I. alipionis and no significant differences where found in morphology or degree of pigmentation. As the cave population is known for at least 30 years and is apparently isolated from epigean streams, it is classified as troglophilic. The discovery of this troglophilic species in the Santana Cave is an additional strong argument for the conservation of that cave.

Saving our science from ourselves: the plight of biological classification

Saving our science from ourselves: the plight of biological classification. Biological classification ( nomenclature, taxonomy, and systematics) is being sold short. The desire for new technologies, faster and cheaper taxonomic descriptions, identifications, and revisions is symptomatic of a lack of appreciation and understanding of classification. The problem of gadget-driven science, a lack of best practice and the inability to accept classification as a descriptive and empirical science are discussed. The worst cases scenario is a future in which classifications are purely artificial and uninformative.

O enigma da "reação espermatofórica": breve síntese do conhecimento sobre a estrutura e o funcionamento dos espermatóforos dos cefalópodes (Mollusca: Cephalopoda)

Cefalópodes coleóides (lulas, sépias e polvos) produzem espermatóforos muito complexos que são transferidos à fêmea durante a cópula por meio do hectocótilo, um apêndice modificado nos machos. Durante a transferência à fêmea, ocorre a chamada "reação espermatofórica", complexo processo de evaginação do aparato ejaculatório do espermatóforo, que conduz à exteriorização da massa espermática e corpo cimentante. A presente revisão sintetiza o conhecimento acerca da morfologia e funcionamento desta estrutura exclusiva dos coleóides, identificando lacunas e definindo estratégias que possibilitem avanços na área. Poucos trabalhos abordam com detalhes a morfologia e anatomia funcional dos espermatóforos dos cefalópodes, grande parte do conhecimento acerca da estrutura do espermatóforo tendo sido gerada por trabalhos clássicos do século XIX e início do século XX. Investigações acerca do funcionamento dos espermatóforos são consideravelmente mais raras, estando o conhecimento básico sobre a reação espermatofórica restrito a apenas 19 espécies de coleóides. A revisão da literatura especializada permite sugerir que existem dois tipos básicos de fixação de espermatóforos em Decapodiformes (lulas e sepióides): fixação superficial e implante profundo (ou intra-dérmico). Na fixação superficial, comum em diversas espécies (e.g., Loliginidae, Sepiidae, Ommastrephidae), a base dos espermatângios é aderida ao tecido-alvo aparentemente por meio do corpo cimentante, a partir de substâncias adesivas e, em alguns casos, estruturas de fixação. No implante profundo, comum em alguns grupos de lulas oceânicas e de águas profundas (e.g., Architeuthidae, Cranchiidae, Octopoteuthidae, Sepiolidae), os espermatóforos implantam-se inteiramente no corpo da fêmea, de forma autônoma. Permanece desconhecido o mecanismo responsável pelo implante profundo. Em Octopodiformes (polvos), o espermatóforo é inserido no gonoduto feminino, alcançando a glândula oviducal, onde estão localizadas as espermatecas, ou a cavidade do ovário. Como o funcionamento extracorpóreo dos espermatóforos depende exclusivamente da intrincada estrutura e organização de seus componentes (e.g., membranas e túnicas), somente investigações detalhadas dessas estruturas proverão as bases para a compreensão do funcionamento e da exata função do complexo espermatóforo dos coleóides. Recomenda-se o desenvolvimento de um protocolo simples e eficiente para coloração e preparação total de espermatóforos, de forma que seja possível expandir as descrições morfológicas do espermatóforo em estudos taxonômicos e anatômicos, permitindo, portanto, ampliação do conhecimento acerca desta enigmática estrutura.

Systematics of Lamontichthys Miranda-Ribeiro (Siluriformes: Loricariidae), with the description of two new species

The taxonomic revision of the genus Lamontichthys Miranda-Ribeiro, based on the examination of 164 specimens of different river drainages throughout the Amazon basin, revealed the presence of six species of which two are new. Lamontichthys filamentosus occurs in the upper and middle portions of the rio Amazonas basin; L. llanero in the río Orinoco basin; L. maracaibero in the lago Maracaibo basin; and L. stibaros in the upper río Amazonas basin. Lamontichthys avacanoeiro, new species, occurs in the upper rio Tocantins basin; and L. parakana, new species, in the lower rio Tocantins basin. The new species represent a considerable extension in the so far known distribution of the genus. A parsimony analysis, including 87 osteological and external morphological characters from Lamontichthys and related taxa (total of 16), resulted in three most parsimonious trees with 194 steps (CI = 0.73 and RI = 0.78). The hypothesis of monophyly of Lamontichthys is corroborated and supported by six derived characters. Within Lamontichthys two monophyletic assemblages are recognized, one includes L. avacanoeiro and L. stibaros, the other includes L. maracaibero and the clade formed by L. filamentosus and L. llanero. The relationships of Lamontichthys parakana, a species that was not included in the phylogenetic analysis is discussed. The monophyly and relationships of the monotypic genus Pterosturisoma microps are also discussed.

Vocalizations and comments on the relationships of Hypsiboas ericae (Amphibia, Hylidae)

The vocalizations of Hypsiboas ericae (Caramaschi & Cruz, 2000) are described and new information on the external morphology and osteology of the species are presented. H. ericae presents a bony spine in the prepolex and the individuals can present green or brown dorsal color, as other species of the Hypsiboas pulchellus (Duméril & Bibron, 1841) species group. The vocalizations of H. ericae are similar to the vocalizations of Hypsiboas bischoffi (Boulenger, 1887), Hypsiboas guentheri (Boulenger, 1886), and other species in the H. polytaenius (Cope, 1870 "1869") clade of the H. pulchellus species group, but some osteological aspects are different to those found in the majority of the species of this group.

Sex ratio and morphological characteristics of rufous gnateaters, Conopophaga lineata (Aves, Passeriformes) in Atlantic forest fragments

Unequal sex ratios lead to the loss of genetic variability, decreasing the viability of populations in the long term. Anthropogenic activities often disturb the natural habitats and can cause alterations in sex ratio and morphological characteristics of several species. Forest fragmentation is a major conservation concern, so that understanding its effects in natural populations is essential. In this study, we evaluated the sex ratio and the morphological characteristics of Rufous Gnateaters (Conopophaga lineata (Wied, 1831)) in small and large forest fragments in Minas Gerais, Brazil. Birds (n = 89) were sexed by plumage characteristics and molecular markers. The molecular analysis showed that plumage is not a totally reliable method for sexing Rufous Gnateaters. We observed that sex ratio did not differ between large and small forest fragments, but birds in small fragments had larger wings and tarsus. Wing and tarsus changes may affect the movement ability of individuals within and among forest fragments. In conclusion, Rufous Gnateaters have been able to survive in both small and large Atlantic rain forest fragments without altering their sex ratio, but morphological changes can be prejudicial to their long term survival.

Morphological changes in distant muscle fibers following thermal injury in Wistar rats

PURPOSE: Thermal injury causes catabolic processes as the body attempts to repair the damaged area. This study evaluated the effects of a scald injury on the morphology of muscle fibers belonging to a muscle distant from the lesion. METHODS: Thirty Wistar rats were divided into control (C) and scalded (S) groups. Group S was scalded over 45% of the body surface, standardized by body weight. Rats in both groups were euthanized at four, seven and 14 days following the injury. The middle portions of the medial gastrocnemius muscles were sectioned, stained with hematoxylin and eosin and Picrosirius, and submitted to histological analysis. RESULTS: Control group sections exhibited equidistantly distributed polygonal muscle fibers with peripheral nuclei, characteristic of normal muscle. The injured group sections did not consistently show these characteristics; many fibers in these sections exhibited a rounded contour, variable stain intensities, and greater interfiber distances. A substantially increased amount of connective tissue was also observed on the injured group sections. CONCLUSION: This experimental model found a morphological change in muscle distant from the site of thermal injury covering 45% of the body surface.

Avaliação citométrica dos adipócitos localizados no tecido subcutâneo da parede anterior do abdome após infiltração percutânea de CO2

OBJETIVO: Avaliar os efeitos da infiltração de dióxido de carbono em adipócitos presentes na parede abdominal. MÉTODOS: Quinze voluntárias foram submetidas a sessões de infusão de CO2 durante três semanas consecutivas (duas sessões por semana com intervalos de dois a três dias entre cada sessão). O volume de gás carbônico infundido por sessão, em pontos previamente demarcados, foi sempre calculado com base na superfície da área a ser tratada, com volume infundido fixo de 250 mL/100cm² de superfície tratada. Os pontos de infiltração foram demarcados respeitando-se o limite eqüidistante 2cm entre eles. Em cada ponto se injetou 10mL, por sessão, com fluxo de 80mL/min. Foram colhidos fragmentos de tecido celular subcutâneo da parede abdominal anterior antes e após o tratamento. O número e as alterações histomorfológicas dos adipócitos (diâmetro médio, perímetro, comprimento, largura e número de adipócitos por campos de observação) foram mensurados por citometria computadorizada. Os resultados foram analisados com o teste t de Student pareado, adotando-se nível de significância de 5% (p<0,05). RESULTADOS: Encontrou-se redução significativa no número de adipócitos da parede abdominal e na área, diâmetro, perímetro, comprimento e largura após o uso da hipercapnia (p=0,0001). CONCLUSÃO: A infiltração percutânea de CO2 reduz a população e modifica a morfologia dos adipócitos presentes na parede abdominal anterior.

Primeiro registro de Trypanosoma vivax em bovinos no Estado do Rio Grande do Sul, Brasil

Este estudo teve o objetivo de relatar a ocorrência de Trypanosoma vivax no Sul do Brasil. O protozoário foi diagnosticado em esfregaço sanguíneo de um bovino e a identificação baseada na morfologia das formas tripomastigotas e confirmada pela técnica de reação em cadeia de polimerases (PCR). O animal infectado apresentou sintomatologia compatível com a forma nervosa da infecção por T. vivax. Outros bovinos que compartilhavam o mesmo ambiente apresentaram resultados negativos para T. vivax por PCR. Este é o primeiro registro de T. vivax no Estado do Rio Grande do Sul e na região Sul do Brasil.

Morphology and reproduction of Mesophyllum erubescens (Foslie) Me. Lemoine (Corallinales, Rhodophyta) from Southern Brazil

The genus Mesophyllum Me. Lemoine includes around 147 species, of which only three have been referred to the Brazilian coast. Mesophyllum erubescens was originally described from Fernando de Noronha Archipelago, Brazil (type locality). Here we present the first detailed description of M. erubescens based on Brazilian material. Samplings were made through scuba diving at the Biological Marine Reserve of Arvoredo Island, Santa Catarina. The relations of M. erubescens with other similar species, especially from the American Atlantic studied by W.R. Taylor are discussed.

Fatores preditivos do maior número de estádios na cirurgia micrográfica de Mohs para o tratamento do carcinoma espinocelular da cabeça

FUNDAMENTOS: Os carcinomas espinocelulares da pele da cabeça têm como opção terapêutica mais segura a cirurgia micrográfica de Mohs, que apresenta os menores índices de recidiva e a máxima preservação tecidual. Características dos carcinomas espinocelulares podem estar relacionadas a maior número de estádios cirúrgicos. OBJETIVO: Definir características dos carcinomas espinocelulares que sejam preditoras de maior número de estádios na cirurgia de Mohs. MÉTODOS: Análise retrospectiva de 51 carcinomas espinocelulares da cabeça tratados pela cirurgia de Mohs para determinar fatores de risco de maior número de estádios. Foram analisados limites clínicos, morfologia, recidiva, histologia e tamanho, relacionando-os ao número de estádios cirúrgicos. A análise estatística foi realizada pelo teste exato de Fisher e regressão logística multivariada. RESULTADOS: Os carcinomas recidivados tiveram tendência a maior número de estádios (p=0,081). Os tumores com limites imprecisos apresentaram três vezes mais possibilidades de maior número de fases na análise da razão de chances. Esse achado foi compatível com dados da literatura, apesar de não ter sido estatisticamente significante. CONCLUSÃO: Características pré-operatórias dos carcinomas espinocelulares, como recidiva e limites imprecisos, apesar de não preditivas, indicaram tendência a maior número de estádios na cirurgia micrográfica de Mohs.

Aerobic and anaerobic metabolism for the zebrafish, Danio rerio, reared under normoxic and hypoxic conditions and exposed to acute hypoxia during development

In order to verify the influence of chronic and acute ambient oxygen levels from egg to adult stage of the zebrafish, in vivo oxygen consumption (MO2), critical tensions of oxygen (Pcrit), heart rate (fH) and total body lactate concentration (Lc) were determined for Danio rerio (Hamilton, 1822) raised at 28 °C under normoxic (7.5 mgO2.L-1 or 80 mm.Hg-1) and hypoxic conditions (4.3 mgO2.L-1) and exposed to acute hypoxia during different developmental stages. Our findings confirmed that very early stages do not respond effectively to ambient acute hypoxia. However, after the stage corresponding to the age of 30 days, D. rerio was able to respond to acute hypoxia through effective physiological mechanisms involving aerobic and anaerobic metabolism. Such responses were more efficient for the fishes reared under hypoxia which showed that D. rerio survival capability increased during acclimation to mild hypoxia. Measurements of body mass and length showed that moderate hypoxia did not affect growth significantly until the fish reached the stage of 60 days. Moreover, a growth delay was verified for the hypoxic-reared animals. Also, the D. rerio eggs-to-larvae survival varied from 87.7 to 62.4% in animals reared under normoxia and mild hypoxia, respectively. However, the surviving animals raised under moderated hypoxia showed a better aptitude to regulate aerobic and anaerobic capacities when exposed to acute hypoxia.

Marine influence in the Barreiras Formation, State of Alagoas, northeastern Brazil

Tidal processes were important for deposition of the Barreiras Formation located in northern Brazil, while correlatable deposits in northeastern Brazil have been traditionally related to continental environments. Facies analysis in southern Alagoas revealed that the Barreiras Formation consists of cross-stratified conglomerates and sandstones (facies Sx and Cgx), compound cross-stratified sandstones (facies Cx), and heterolithic beddings (facies H). A significant portion of these deposits occurs within channel morphologies displaying fining and thinning upward successions. An abundance of sedimentary features is comparable to those from the northern Brazilian counterpart. These include: tidal bundles; herringbone cross-stratification; heterolithic beddings with sandstone and mudstone beds in sharp contacts; and ichnofossils mostly consisting of Ophiomorpha nodosa, Skolithos and Planolites. Altogether, these features point to a marginal marine depositional setting dominated by tidal processes, which are related to an estuarine system, an interpretation also provided for the Barreiras Formation in northern Brazil. The widespread occurrence of deposits with unambiguous evidence of tidal processes in the Barreiras Formation of northern Brazil, and now in the State of Alagoas, leads to argue that the early/middle Miocene worldwide marine transgression might have left a much more widespread sedimentary record along the Brazilian coast than currently regarded.

Low temperature synthesis of CdSiO3 nanostructures

We report the synthesis of single-phase, crystalline CdSiO3 nanostructures at 580ºC; to the best of our knowledge, this is the lowest temperature at which this material is reported to form. The desired phase does not form below 580ºC, since the diffraction peaks are shifted to lower angles in the material treated at 570ºC when compared to JDPDS Card No. 85-0310. The source of silicon has strong influence on the product morphology: Na2SiO3 yields single-phase CdSiO3 in needle-shaped nanostructures, while high surface area mesostructured SiO2 yields coralloid-shaped particles. Low angle X-ray diffractometry reveals that the mesostructured nature of the silica precursor is not maintained in the resulting CdSiO3. Scanning electron microscopy suggests that in this case a transition occurs between the spherical morphology of the precursor and the needle-shape morphology of the material prepared from Na2SiO3. The surface area of the silica precursor has a strong influence in the reaction, since the use of commercial silica with a lower surface area does not yield the desired product.

Atherinella blackburni (Schultz, 1949) at Itamambuca Beach, Ubatuba, SP: ecological characterization and distribution on the Brazilian coast (Teleostei: Atheriniformes: Atherinopsidae)

Atherinella blackburni is a silverside species whose occurrence on the Brazilian coast was not properly registered until recently. So far, records of its distribution along the Brazilian shore were limited to Itaparica Island, Bahia State, and Porto Inhaúma, Rio de Janeiro State. In a recent survey of the ichthyofauna of Itamambuca Beach, Ubatuba, São Paulo State, 100 specimens of this species were collected, yielding a considerable source of information regarding its ecology and a new southern limit of its distribution. A detailed survey of an ichthyological collection revealed lots of this species from regions of the Brazilian Northeast, resulting in a northward expansion of the occurrence of A. blackburni in Brazilian waters. Besides the populations found on the Brazilian coast, the species also occurs discontinuously in the Atlantic coasts of Costa Rica, Panama and Venezuela. Meristic and morphometric analysis showed overlapped values between Brazilian populations and the ones closer to the Caribbean. An ecological study of A. blackburni at Itamambuca Beach revealed that it is a predominantly diurnal species with preference for warm and salty waters, often occurring in sandy-bottom environments. It was more abundant in Summer and Winter, when individuals with smaller values of length and weight also occurred.