Effectiveness of sealing active proximal caries lesions with an adhesive system: 1-year clinical evaluation

The objective of this study was to evaluate the effectiveness of a therapeutic sealant to arrest non-cavitated proximal carious lesion progression. The study population comprised 44 adolescents who had bitewing radiographs taken for caries diagnosis. Non-cavitated lesions extending up to half of dentin thickness were included in the sample. In the experimental group (n = 33), the proximal caries-lesion surfaces were sealed with an adhesive (OptiBond Solo, Kerr) after tooth separation. The control group (n = 11) received no treatment, except for oral hygiene instructions including use of dental floss. Follow-up radiographs were taken after one year and were analyzed in comparison with baseline radiographs. In a blind study setting, visual readings were performed by two examiners, blinded to whether the examined radiograph was baseline or follow-up, and whether it concerned a test or control lesion. The efficacy of sealing treatment was evaluated by the McNemar test (0.05). About 22% of the sealed lesions showed reduction, 61% showed no change and 16% showed progression. For the control lesions, the corresponding values were 27%, 36% and 36% respectively. The number of lesions that showed reduction and no changes were merged and therefore 83.3% of the sealed lesions and 63.6% of the control lesions were considered clinically successful. No statistical significance was detected (p > 0.05). In the course of 1 year, sealing proximal caries lesions was not shown to be superior to lesion monitoring.

Isolation and characterization of Flavobacterium columnare (Bernardet et al. 2002) from four tropical fish species in Brazil

Flavobacterium columnare is the causative agent of columnaris disease in freshwater fish, implicated in skin and gill disease, often causing high mortality. The aim of this study was the isolation and characterization of Flavobacterium columnare in tropical fish in Brazil. Piracanjuba (Brycon orbignyanus), pacu (Piaractus mesopotamicus), tambaqui (Colossoma macropomum) and cascudo (Hypostomus plecostomus) were examined for external lesions showing signs of colunmaris disease such as greyish white spots, especially on the head, dorsal part and caudal fin of the fish. The sampling comprised 50 samples representing four different fish species selected for study. Samples for culture were obtained by skin and kidney scrapes with a sterile cotton swabs of columnaris disease fish and streaked onto Carlson and Pacha (1968) artificial culture medium (broth and solid) which were used for isolation. The strains in the liquid medium were Gram negative, long, filamentous, exhibited flexing movements (gliding motility), contained a large number of long slender bacteria and gathered into ‘columns'. Strains on the agar produced yellow-pale colonies, rather small, flat that had rhizoid edges. A total of four Flavobacterium columnare were isolated: 01 Brycon orbignyanus strain, 01 Piaractus mesopotamicus strain, 01 Colossoma macropomum strain, and 01 Hypostomus plecostomus strain. Biochemical characterization, with its absorption of Congo red dye, production of flexirubin-type pigments, H2S production and reduction of nitrates proved that the isolate could be classified as Flavobacterium columnare.

Two-dimensional gel electrophoretic protein profile analysis during seed development of Ocotea catharinensis: a recalcitrant seed species

The aim of the present work was to characterize changes in the protein profile throughout seed development in O. catharinensis, a recalcitrant species, by two-dimensional gel electrophoresis. Protein extraction was undertaken by using a thiourea/urea buffer, followed by a precipitation step with 10% TCA. Comparative analysis during seed development showed that a large number of proteins were exclusively detected in each developmental stage. The cotyledonary stage, which represents the transition phase between embryogenesis and the beginning of metabolism related to maturation, presents the highest number of stage-specific spots. Protein identification, through MS/MS analysis, resulted in the identification of proteins mainly related to oxidative metabolism and storage synthesis. These findings contribute to a better understanding of protein metabolism during seed development in recalcitrant seeds, besides providing information on established markers that could be useful in defining and improving somatic embryogenesis protocols, besides monitoring the development of somatic embryos in this species.

Mechanisms of pigmentation loss in subterranean fishes

Troglobitic (exclusively subterranean) organisms usually present, among their apomorphies related to the subterranean life (troglomorphisms), the regression of eyes and melanic pigmentation. The degree of regression varies among species, from a slight reduction to the complete loss of eyes and dark pigmentation, without a taxonomic correlation. While mechanisms of eye reduction have been intensively investigated in some troglobites such as the Mexican blind tetra characins, genus Astyanax, and the European salamander, Proteus anguinus, few studies have focused on pigmentation. The Brazilian subterranean ichthyofauna distinguishes not only by the species richness (23 troglobitic fishes so far known) but also by the variation in the degree of reduction of eyes and pigmentation. This study focused on Brazilian fishes completely devoid of melanic pigmentation: the characiform Stygichthys typhlops (Characidae) and the siluriforms Ancistrus formoso (Loricariidae), Rhamdiopsis sp.1 (Heptapteridae; from caves in the Chapada Diamantina, Bahia) and Rhamdiopsis sp. 2 (cave in Campo Formoso, Bahia). In order to investigate if such depigmentation is the result of blockage in some step in the melanogenesis, in vitro tests of administration of L-DOPA were done, using caudal-fin fragments extracted from living fish. Except for Rhamdiopsis sp. 2, all the studied species were DOPA(+), i.e., melanin was synthesized after L-DOPA administration. This indicates these fish do have melanophores but they are unable to convert L-tyrosine to L-DOPA. On the other hand, Rhamdiopsis sp. 2, like the albino specimens of Trichomycterus itacarambiensis previously studied (which correspond to one third of the population), are DOPA(-), either because the block of melanin synthesis occurs downstream in melanogenesis, which is probably the case with T. itacarambiensis (monogenic system in view of the phenotypic discontinuity), or because the so-called albinos do no possess melanophores. The physiological loss in the ability to synthesize melanin, apparently caused by different genetic processes in DOPA(+) and in DOPA(-) fishes, may co-exist in subterranean populations with a decrease in the density of melanophores, as observed in the pigmented two thirds of T. itacarambiensis population, a morphological reduction apparently controlled by polygenic systems producing a continuous phenotypic variation.

An unusual, dwarf new species of Neotropical freshwater stingray, Plesiotrygon nana sp. nov., from the upper and mid Amazon basin: the second species of Plesiotrygon (Chondrichthyes: Potamotrygonidae)

A new species of the relatively poorly known Neotropical freshwater stingray genus Plesiotrygon Rosa, Castello & Thorson, 1987 is described from the main channel and smaller tributaries (Ríos Itaya and Pachitea) of the upper Amazon basin in Peru. The first specimen to be collected, however, was from much farther east in Rio Solimões in 1996, just down-river from Rio Purus (specimen unavailable for this study). Plesiotrygon nana sp. nov., is a very distinctive and unusually small species of freshwater stingray (Potamotrygonidae), described here mostly from three specimens representing different size classes and stages of sexual maturity. Plesiotrygon nana sp. nov., is distinguished from its only congener, P. iwamae Rosa, Castello & Thorson, 1987, by numerous unique features, including: dorsal coloration composed of very fine rosettes or a combination of spots and irregular ocelli; very circular disc and snout; very small and less rhomboidal spiracles; short snout and anterior disc region; narrow mouth and nostrils; denticles on dorsal tail small, scattered, not forming row of enlarged spines; adult and preadult specimens with significantly fewer tooth rows; fewer caudal vertebrae; higher total pectoral radials; very small size, probably not surpassing 250 mm disc length or width, males maturing sexually at around 180 mm disc length and 175 mm disc width; distal coloration of tail posterior to caudal stings usually dark purplish-brown; and features of the ventral lateral-line canals (hyomandibular canal very narrow, infraorbital and supraorbital canals not undulated, supraorbital and infraorbital loops small and narrow, supraorbital loop very short, not extending posteriorly to level of mouth, jugular and posterior infraorbital canals short, not extending caudally to first gill slits, subpleural loop very narrow posteriorly; absence of anterior and posterior subpleural tubules). To provide a foundation for the description of P. nana sp. nov., morphological variation in P. iwamae was examined based on all type specimens as well as newly collected and previously unreported material. Two specimens topotypic with the male paratype of P. nana sp. nov., referred to here as Plesiotrygon cf. iwamae, are also reported. Relationships of the new species to P. iwamae are discussed; further characters indicative of Plesiotrygon monophyly are proposed, but the genus may still not be valid. Plesiotrygon nana sp. nov., is commercialized with some regularity in the international aquarium trade from Iquitos (Peru), an alarming circumstance because nothing is known of its biology or conservation requirements.

A new species of Neotropical freshwater stingray of the genus Potamotrygon Garman, 1877 from the Río Madrede Díos, Peru (Chondrichthyes: Potamotrygonidae)

Potamotrygon tatianae sp. nov., is described from Río Madre de Díos, Peru, upper Rio Madeira basin. The new species is distinguished from all congeners by a unique combination of characters, including its dorsal color pattern formed by a relatively slender, highly convoluted, beige to dark brown vermicular pattern, a single row of dorsal tail spines, and a relatively longer tail posterior to caudal stings. Potamotrygon tatianae sp. nov., occurs sympatrically with other species of Potamotrygon (P. falkneri, P. orbignyi and P. motoro). From the similar species P. falkneri, P. tatianae sp. nov., is further distinguished by the absence of circular, reniform, and oval spots, by its proportionally much longer tail, by having dorsal tail spines in one irregular row, and by features of the ventral lateral-line canal, dermal denticles and neurocranium. From P. orbignyi, the new species is distinct by lacking a reticulate pattern on dorsal disc and by the presence of two angular cartilages. From P. motoro, P. tatianae sp. nov., is further separated by the lack of ocelli formed by strong black concentric rings, by the more flattened aspect of its head and disc, and by having smaller and more numerous teeth. The discovery of a new species that so closely resembles a congeneric form in color pattern, a feature highly variable within the latter, highlights the importance of examining large series of individuals and of detailed morphological analyses in revealing the potentially highly cryptic nature of the diversity within the family.

A new species of Pimelodus La Cépède, 1803 (Siluriformes: Pimelodidae) from rio Ribeira de Iguape basin, Brazil

Pimelodus multicratifer, a new species, is described from the rio Ribeira de Iguape basin. The new species differs from the other Pimelodus species by the following features: 26 to 30 gill rakers on the first branchial arch; a combination of three to six rows of dark spots regularly or irregularly scattered on the flanks and several small dark spots irregularly scattered on the dorsal surface of head, supraoccipital process, and sometimes on the dorsal and caudal fins; striated lips; maxillary barbels reaching between posterior tip of the pelvic-fin rays and posterior tip of the middle caudal-fin rays.

Ituglanis mambai, a new subterranean catfish from a karst area of Central Brazil, rio Tocantins basin (Siluriformes: Trichomycteridae)

Ituglanis mambai, new species, is described from a cave in the Mambaí karst area, State of Goiás, Central Brazil. The new species distinguishes from epigean and cave congeners by the combination of the following characteristics: posterior supraoccipital fontanel absent; pectoral-fin rays usually i,7; six pleural ribs; total vertebrae 37-38 behind Weberian apparatus; shorter predorsal length (65.1-70.8% SL); shorter caudal peduncle length (8.4-11.9% SL); shorter dorsal-fin base length (7.7-11.3% SL); wider interobital width (29.2-36.5% HL); larger mouth width (43.4-64.0% HL); intermediate between epigean and other cave Ituglanis species as regards to both eyes (diameter varying from 0.5 to1.0 mm in adults, 7.8-10.1 % HL) and pigmentation, composed by irregular light brown spots along the body. The latter indicate the troglobitic status for I. mambai. In addition, this species has the maxillae with a discrete medial-posterior projection; fronto-lacrimal one half-length of the maxillae and pointed backwards; posterior process of palatine half its length, with a tenuous medial concavity; 14 dorsal and 12 ventral procurrent rays. In the natural habitat, I. mambai displayed cryptobiotic habits, trying to hide in the graveled bottom or under boulders when disturbed, apparently showing a negative response to light. It was observed a preference to slow-moving waters. Recent flood marks were observed in the stream conduit in March/April 2007 (end of the rainy season) when less individuals were observed on 300 m of the subterranean stream compared to September 2004 (end of the dry season).

Potamotrygon boesemani (Chondrichthyes: Myliobatiformes: Potamotrygonidae), a new species of Neotropical freshwater stingray from Surinam

Potamotrygon boesemani, new species, is described from the Corantijn river drainage in Surinam. The species has a diagnostic dorsal color pattern formed by deep orange to red ocellated spots of irregular form, encircled by relatively broad black rings. Potamotrygon boesemani is distinguished from other ocellated congeners (P. motoro, P. henlei and P. leopoldi) by the more intensely colored ocelli, which are usually yellow in the latter species. From P. motoro it is also distinguished by the darker dorsal background coloration, by the broader black contour of the dorsal ocelli, and by the irregular form of the ocelli as compared to the more rounded shape in the latter species. From P. henlei and P. leopoldi, it is distinguished by the lack of ocelli on tail. From the tentatively identified specimen of P. ocellata, which also has dark orange ocelli, the irregular contour of the ocelli in the new species is also distinctive. The teeth are relatively smaller and in greater number than in P. motoro and P. ocellata, with up to 45 rows in the upper jaw.

Two new species of the Hypostomus cochliodon group (Siluriformes: Loricariidae) from the rio Negro basin in Brazil

Two new species of Hypostomus are described from the middle and upper rio Negro in Brazil. They are assigned to the Hypostomus cochliodon group (sensu Armbruster, 2003) by possessing few spoon-shaped teeth, and dentary angle averaging less than 80º. Hypostomus kopeyaka is described from the rio Tiquié, a tributary of the rio Uaupés, upper rio Negro basin, presents a unique color pattern among the Hypostomus species belonging to the Hypostomus cochliodon group, consisting of conspicuously horizontally elongated, closely-set black spots over the entire dorsal and lateral surfaces of the body. Hypostomus weberi is described from the middle rio Negro and can be distinguished from all remaining Hypostomus species belonging to the Hypostomus cochliodon group by possessing a unique color pattern consisting in large, rounded, widelyspaced black spots over body and fins.

Induction of a gloverin-like antimicrobial polypeptide in the sugarcane borer Diatraea saccharalis challenged by septic injury

Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) is an important pest for Brazilian sugarcane. In the present study, we detected two distinct spots in hemolymph from septic injured larvae (HDs1 and HDs2), which are separated by 2DE gel electrophoresis. Both spots were subjected to in-gel tryptic digestion and MALDI-TOF/TOF analysis, which revealed the sequence VFGTLGSDDSGLFGK present in both HDs1 and HDs2. This sequence had homology and 80% identity with specific Lepidoptera antimicrobial peptides called gloverins. Analyses using the ImageMaster 2D software showed pI 8.94 of the HDs1 spot, which is similar to that described to Hyalophora gloveri gloverin (pI 8.5). Moreover, the 14-kDa molecular mass of the spot HDs1 is compatible to that of gloverins isolated from the hemolymph of Trichoplusia ni, Helicoverpa armigera and H. gloveri. Antimicrobial assays with partially purified fractions containing the HDs1 and HDs2 polypeptides demonstrated activity against Escherichia coli. This is the first report of antimicrobial polypeptides in D. saccharalis, and the identification of these peptides may help in the generation of new strategies to control this pest.

Dimorfismo sexual alar em Aedes scapularis (Diptera: Culicidae)

A detecção do sexo de mosquitos da família Culicidae é importante em estudos faunísticos e epidemiológicos, pois somente as fêmeas possuem competência vetora para patógenos. O dimorfismo sexual de genitália e de apêndices cefálicos é, em geral, facilmente visível em culicídeos. As asas também podem ser dimórficas e assim poderiam complementar o procedimento de sexagem. No entanto, tal distinção não é facilmente notável à observação direta. Visando descrever formalmente o dimorfismo sexual alar em Aedes scapularis, um culicídeo vetorialmente competente para arbovírus e filárias, asas de machos e fêmeas foram comparadas usando-se métodos de morfometria geométrica e análise estatística multivariada. Nestas análises, populações dos municípios São Paulo e Pariquera-Açu (Estado de São Paulo) foram amostradas. A forma das asas mostrou evidente dimorfismo sexual, o que permitiu um índice de acurácia de 100% em testes-cegos de reclassificação, independentemente da origem geográfica. Já o tamanho alar foi sexualmente dimórfico apenas na população de São Paulo. Aparentemente, a forma alar é evolutivamente mais estável que o tamanho, interpretação que está de acordo com a teoria de Dujardin (2008b), de que a forma alar de insetos seria composta por caracteres genéticos quantitativos e pouco influenciada por fatores não-genéticos, enquanto que o tamanho alar seria predominantemente determinado por plasticidade decorrente de influências ambientais.

T.W. Adorno e a psicologia social

Neste ensaio, ressalta-se a importância da disciplina Psicologia Social na obra de T. W. Adorno e a concepção que formula acerca dessa disciplina. Esse autor defende que há uma nova forma de configuração dos indivíduos, expressada por atitudes e comportamentos individuais padronizados e por um ego frágil, facilmente cooptado por movimentos sociais totalitários. Tais indivíduos surgem em uma sociedade caracterizada por uma forma de dominação calcada na racionalidade administrativa e tecnológica. Para esse autor, a Psicologia Social deveria estudar esse objeto para que, com o esclarecimento produzido e difundido, os indivíduos possam resistir à adesão cega a movimentos sociais irracionais, tal como o fascismo, insistindo que a determinação desses movimentos não é individual, mas social.

Desenvolvimento de conceitos em cegos congênitos: caminhos de aquisição do conhecimento

O objetivo deste trabalho foi estudar o desenvolvimento de conceitos por cegos congênitos. Participaram sete cegos congênitos, de ambos os sexos, com idades entre 8 e 13 anos. Foi solicitado aos participantes que definissem 15 conceitos, subdivididos em concretos e abstratos. As respostas foram agrupadas em 13 categorias. Verificou-se que cada tipo de conceito envolve formas diferenciadas de definição e de utilização de recursos perceptivos. Foram identificados alguns meios utilizados pelo cego congênito na aquisição do conhecimento, evidenciando a multiplicidade de possibilidades de aquisição e expressão de conceitos. As implicações deste trabalho para o processo de ensino/aprendizagem de cegos foram consideradas.

O aluno cego: preconceitos e potencialidades

Este artigo analisa a cegueira, os preconceitos a ela associados e as potencialidades de pessoas cegas, especialmente do aluno cego. Salienta a ênfase dada ao sentido da visão no processo de aquisição de conhecimentos e considera os preconceitos comumente associados à capacidade de aprendizagem do cego.