Short- and long-term, salinity-induced modulation of V-ATPase activity in the posterior gills of the true freshwater crab, Dilocarcinus pagei (Brachyura, Trichodactylidae)

To better understand the biochemical mechanisms underlying anisosmotic extracellular regulation in the freshwater Brachyura, we kinetically characterized the V-ATPase from the posterior gills of Dilocarcinus pagei, acclimated for 10 days to salinities up to 21%.. Specific activity was highest in fresh water (26.5 +/- 2.1 U mg(-1)), decreasing in 5 parts per thousand to 21 parts per thousand, attaining 3-fold less at 15 parts per thousand. Apparent affinities for ATP and Mg(2+) respectively increased 3.2- and 2-fold at 10 parts per thousand, suggesting expression of different isoenzymes. In a 240-h time-course study of exposure to 21%., maximum specific activity decreased 2.5- to 4-fold within 1 to 24 h while apparent affinities for ATP and Mg(2+) respectively increased by 12-fold within 24 h and 2.4-fold after 1 h, unchanged thereafter. K(I) for bafilomycin A(1) decreased 150-fold after 1 h, remaining constant up to 120 h. This is the first kinetic analysis of V-ATPase specific activity in crustacean gills during salinity acclimation. Our findings indicate active gill Cl(-) uptake by D. pagei in fresh water, and short- and long-term down-regulation of V-ATPase-driven ion uptake processes during salinity exposure, aiding in comprehension of the biochemical adaptations underpinning the establishment of the Brachyura in fresh water. (C) 2011 Elsevier Inc. All rights reserved.

Structural and Biochemical Correlates of Na(+), K(+)-ATPase Driven Ion Uptake Across the Posterior Gill Epithelium of the True Freshwater Crab, Dilocarcinus pagei (Brachyura, Trichodactylidae)

To better comprehend the structural and biochemical underpinnings of ion uptake across the gills of true freshwater crabs, we performed an ultrastructural, ultracytochemical and morphometric investigation, and kinetically characterized the Na(+), K(+)-ATPase, in posterior gill lamellae of Dilocarcinus pagei. Ultrastructurally, the lamellar epithelia are markedly asymmetrical: the thick, mushroom-shaped, proximal ionocytes contain elongate mitochondria (41% cell volume) associated with numerous (approximate to 14 mu m(2) membrane per mu m(3) cytoplasm), deep invaginations that house the Na(+), K(+)-ATPase, revealed ultracytochemically. Their apical surface is amplified (7.5 mu m(2) mu m(-2)) by stubby evaginations whose bases adjoin mitochondria below the subcuticular space. The apical membrane of the thin, distal ionocytes shows few evaginations (1.6 mu m(2) mu m(-2)), each surrounding a mitochondrion, abundant in the cytoplasm below the subcuticular space; basolateral invaginations and mitochondria are few. Fine basal cytoplasmic bridges project across the hemolymph space, penetrating into the thick ionocytes, suggesting ion movement between the epithelia. Microsomal Na(+), K(+)-ATPase specific activity resembles marine crabs but is approximate to 5-fold less than in species from fluctuating salinities, and freshwater shrimps, suggesting ion loss compensation by strategies other than Na(+) uptake. Enzyme apparent K(+) affinity attains 14-fold that of marine crabs, emphasizing the relevance of elevated K(+) affinity to the conquest of fresh water. Western blotting and biphasic ouabain inhibition disclose two alpha-subunit isoforms comprising distinct functional isoenzymes. While enzyme activity is not synergistically stimulated by NH(4)(+) and K(+), each increases affinity for the other, possibly assuring appropriate intracellular K(+) concentrations. These findings reveal specific structural and biochemical adaptations that may have allowed the establishment of the Brachyura in fresh water. J. Exp. Zool. 313A:508-523, 2010. (C) 2010 Wiley-Liss, Inc.

Estimating the True Incidence of Rubella

The true incidence of infectious diseases is difficult to determine from surveillance or from notification data. The proportion of new infections of rubella yields a model from serological surveys. The discrepancy between results and official notification data before vaccination era leads one to suspect the presence of hidden infections. Simulation on 80% of effective vaccination coverage shows a similar discrepancy of the total number of infections compared to notification data.

Parceria público x privada no desenvolvimento de pesquisa em melhoramento genético animal

O melhoramento genético animal é, normalmente, pesquisado e desenvolvido nas universidades e instituições públicas de pesquisa do Brasil. No entanto, os rebanhos de exploração zootécnica, verdadeiros objetivos desses estudos, pertencem à iniciativa privada. O melhoramento genético animal e as parcerias público-privadas constituem-se em um caso especial de grande sucesso, que é analisado no presente texto, com ênfase especial ao Grupo de Melhoramento Animal e Biotecnologia da Faculdade de Zootecnia e Engenharia de Alimentos da Universidade de São Paulo, instituição de origem dos autores. O sucesso desse grupo, medido em atividades de pesquisa e suas conseqüentes publicações, de ensino e formação de recursos humanos e de extensão de serviços à comunidade, é apresentado como incentivo aos pesquisadores das mais diversas áreas ligadas à produção animal.

Morfoanatomia da flor de cinco espécies de Galipea Aubl. e seu significado na evolução de flores tubulosas entre as Rutaceae neotropicais

A maioria dos gêneros da subtribo neotropical Galipeinae (tribo Galipeeae, Rutoideae) tem flores tubulosas, com várias formas e graus de conação e adnação. Galipea e outros gêneros na subtribo apresentam apenas duas anteras férteis mais cinco ou mais estaminódios, o que é intrigante porque na tribo predominam flores pentâmeras isostêmones. Visando elucidar a condição anatômica dessas características e estabelecer estados acurados para caracteres em análises filogenéticas, um estudo morfoanatômico de flores de cinco espécies de Galipea foi realizado, buscando os padrões de vascularização, posição, e união dos segmentos da flor. Destacam-se os resultados: 1) um tubo floral genuíno se forma no terço basal da flor por conação dos filetes e adnação desse tubo estaminal às pétalas; 2) as pétalas são distalmente coerentes umas às outras e aderentes aos filetes por meio de entrelaçamento de tricomas densos - um caso de pseudossimpetalia; 3) dentre as cinco (às vezes seis) estruturas tratadas como estaminódios, apenas as três externas são de fato homólogas a estames esterilizados, as demais surgem como ramificações adaxiais das pétalas; 4) os carpelos são peltados, congenitalmente conatos axial e lateralmente da base do ovário até o nível das placentas, e no estilete e estigma; na zona mediana e superior do ovário eles são unidos apenas posgenitalmente, com a epiderme diferenciada de carpelos contíguos e suturas evidentes na região ventral de cada carpelo; 5) a vascularização do disco sugere origem receptacular. As implicações desses dados para o entendimento da evolução das flores tubulosas em Galipea e grupos relacionados são discutidas.

Neural networks and statistical analysis for classification of corneal videokeratography maps based on Zernike coefficients: a quantitative comparison

PURPOSE: The main goal of this study was to develop and compare two different techniques for classification of specific types of corneal shapes when Zernike coefficients are used as inputs. A feed-forward artificial Neural Network (NN) and discriminant analysis (DA) techniques were used. METHODS: The inputs both for the NN and DA were the first 15 standard Zernike coefficients for 80 previously classified corneal elevation data files from an Eyesys System 2000 Videokeratograph (VK), installed at the Departamento de Oftalmologia of the Escola Paulista de Medicina, São Paulo. The NN had 5 output neurons which were associated with 5 typical corneal shapes: keratoconus, with-the-rule astigmatism, against-the-rule astigmatism, "regular" or "normal" shape and post-PRK. RESULTS: The NN and DA responses were statistically analyzed in terms of precision ([true positive+true negative]/total number of cases). Mean overall results for all cases for the NN and DA techniques were, respectively, 94% and 84.8%. CONCLUSION: Although we used a relatively small database, results obtained in the present study indicate that Zernike polynomials as descriptors of corneal shape may be a reliable parameter as input data for diagnostic automation of VK maps, using either NN or DA.

Resultados preliminares de um sistema de topografia de grande-ângulo usando videoceratógrafo com discos de Plácido

OBJETIVO: Desenvolver a instrumentação e o "software" para topografia de córnea de grande-ângulo usando o tradicional disco de Plácido. O objetivo é permitir o mapeamento de uma região maior da córnea para topógrafos de córnea que usem a técnica de Plácido, fazendo-se uma adaptação simples na mira. MÉTODOS: Utilizando o tradicional disco de Plácido de um topógrafo de córnea tradicional, 9 LEDs (Light Emitting Diodes) foram adaptados no anteparo cônico para que o paciente voluntário pudesse fixar o olhar em diferentes direções. Para cada direção imagens de Plácido foram digitalizadas e processadas para formar, por meio de algoritmo envolvendo elementos sofisticados de computação gráfica, um mapa tridimensional completo da córnea toda. RESULTADOS: Resultados apresentados neste trabalho mostram que uma região de até 100% maior pode ser mapeada usando esta técnica, permitindo que o clínico mapeie até próximo ao limbo da córnea. São apresentados aqui os resultados para uma superfície esférica de calibração e também para uma córnea in vivo com alto grau de astigmatismo, mostrando a curvatura e elevação. CONCLUSÃO: Acredita-se que esta nova técnica pode propiciar a melhoria de alguns processos, como por exemplo: adaptação de lentes de contato, algoritmos para ablações costumizadas para hipermetropia, entre outros.

O rap, o hip-hop e o funk: a "eróptica" da arte juvenil invade a cena das escolas públicas nas metrópoles brasileiras

A irreverência e a criticidade de alguns rappers e o gingar alegre do corpo erótico proposto pelo funk sugerem um novo cenário para as metrópoles do país, em que a pluralidade da arte juvenil surge como forma de enfrentamento das marcas deixadas por fraturas sociais profundas. Os conceitos de "visão dionisíaca de mundo", "estética extrema" e "transvaloração dos valores", de Nietzsche, e o "erotismo", segundo Bataille, nortearam o método de ruptura de campo, concebido por Herrmann. Este, essencial para se repensar as noções de autoridade e tradição na sociedade contemporânea a partir das ideias veiculadas pelo rap e pelo funk. Consideramos que somente uma etnografia do olhar que apanhe a dimensão erótica e irreverente - a "eróptica", segundo Canevacci - destas manifestações poderia nelas identificar uma estética afirmativa e crítica, como diria Nietzsche, capaz de produzir uma verdadeira reversão dos valores em nossa sociedade e, no caso, no interior da própria escola.

Influência das características das substâncias húmicas aquáticas na eficiência da coagulação com o cloreto férrico

The aim of this study was to verify the influence of the apparent molecular size of aquatic humic substances on the effectiveness of coagulation with ferric chloride. Coagulation-filtration tests using jar test and bench-scale sand filters were carried out on samples of water with true color of approximately 100 Hazen units, prepared with aquatic humic substances of different molecular sizes (F1: < 0.45 µm, F2: 100 kDa - 0.45 µm, F3: 30 - 100 kDa and F4': < 30 kDa). For the water samples with lower apparent molecular size fractions, greater dosages of coagulant was needed to remove the color around 5.0 Hanzen units, mainly because these water samples contain higher concentrations of fulvic acids, which exhibited a larger number of negatively-charged groups.

Nanostructured thin films obtained by electrodeposition over a colloidal crystal template: applications in electrochemical devices

Colloidal particles have been used to template the electrosynthesis of several materials, such as semiconductors, metals and alloys. The method allows good control over the thickness of the resulting material by choosing the appropriate charge applied to the system, and it is able to produce high density deposited materials without shrinkage. These materials are a true model of the template structure and, due to the high surface areas obtained, are very promising for use in electrochemical applications. In the present work, the assembly of monodisperse polystyrene templates was conduced over gold, platinum and glassy carbon substrates in order to show the electrodeposition of an oxide, a conducting polymer and a hybrid inorganic-organic material with applications in the supercapacitor and sensor fields. The performances of the resulting nanostructured films have been compared with the analogue bulk material and the results achieved are depicted in this paper.

Ecological aspects of the surf-zone ichthyofauna of Itamambuca Beach, Ubatuba, SP

Sandy beaches are among the most extensive environments in Brazil and are generally threatened by disorderly urban growth due to their location along the coast, where human populations tend to concentrate. This is especially true in southeastern Brazil, where the largest urban areas are located. Thus, better knowledge regarding these natural resources is of considerable importance. The surf zone of sandy beaches is inhabited by a number of fish species, including juveniles seeking both food and shelter from predators. An ecological survey was conducted in the surf zone of Itamambuca beach in the city of Ubatuba, São Paulo State, Brazil, in order to evaluate the composition, structure and dynamics of the fish fauna using community descriptors. Diurnal and nocturnal samples were taken with a beach seine at five oceanographic stations over a 12-month period. Water temperature and salinity were also recorded. A total of 2,147 individuals representing 34 species and 18 families were sampled. The main variation in fish fauna was detected on the diel level, followed by a spatial repartition possibly related to salinity. Seasonal variation was also observed. The five most important species in the overall context were Atherinella brasiliensis, Eucinostomus melanopterus, Mugil sp., Trachinotus goodei and Atherinella blackburni.

Encefalite no litoral paulista: a emergência da epidemia e a reação da mídia impressa

No litoral sul do estado de São Paulo, ocorreu uma epidemia de encefalite pelo arbovírus Rocio de 1975 a 1978. As altas taxas de morbidade e mortalidade causaram impacto social. Neste trabalho, o objetivo foi apresentar um estudo sobre como a mídia impressa relatou os acontecimentos sociais relacionados ao surgimento da epidemia no primeiro semestre de 1975. Reportagens sobre a epidemia no litoral sul foram obtidas do banco de dados dos jornais A Tribuna, Folha de S.Paulo e Jornal da Tarde. Foram analisadas as notícias até o mês de julho de 1975, fase inicial e de maior impacto da epidemia. Com a identificação de casos de encefalite, de causa desconhecida, a Secretaria de Estado da Saúde desaconselhou a ida de turistas para o litoral, utilizando a mídia como veículo de divulgação. Diante das notícias, ocorreu a fuga dos turistas e, consequentemente, a crise do comércio. Observou-se a revolta dos comerciantes, que geraram embates contra a mídia, no que tange à forma de divulgação da epidemia. Alguns prefeitos alegaram inveracidade de notícias publicadas. A proibição feita pelas autoridades sanitárias foi relatada pela mídia de forma abrangente, englobando sujeitos envolvidos nesse discurso. Assim, foram reveladas ao público as tensões geradas entre os detentores do conhecimento científico e o poder econômico local. Os jornais realizaram cobertura abrangente, abordando vários temas, entretanto disseminaram incertezas e fizeram uso de imagens sensacionalistas, além de desarticular acontecimentos biológicos e sociais. Os temas chegaram aos leitores de forma fragmentada e com sentidos sociais comprometidos.

Productive performance and milk protein fraction composition of dairy cows supplemented with sodium monensin

The objective of this work was to evaluate the levels of sodium monensin on lactating cows and their effects on productive performance and milk protein fraction composition. It was used 12 Holstein cows, distributed in four balanced 3 × 3 Latin squares, and fed three diets: one control without monensin, and two diets with monensin at the levels of 24 or 48 mg/kg DM added to the concentrate. Milk production was daily measured throughout the entire experimental period. The samples used for analysis of milk composition were collected on two alternated days from the two daily milking. Non-protein nitrogen, total nitrogen and non-casein nitrogen contents were directly evaluated in the milk, and casein, whey protein and true protein contents were indirectly determined. The use of monensin in the rations reduced dry matter and nutrient intake, especially when diet with 48 mg/kg of dry matter was given. The ration with 24 mg/kg of DM increased milk production, with or without correction, and also fat and lactose yield, and it improved productive efficiency. The levels of monensin in the ratios did not influence contents of milk crude protein, non-protein nitrogen, non-casein nitrogen, true protein, casein, casein/true protein ratio, whey protein, and of all those fractions expressed as percentage of crude protein. The utilization of monensin in the ratio at the dose of 24 mg/kg of DM influences positively the productive performance of lactating cows, and it does not influence the composition of milk protein fractions.

Productive performance and composition of milk protein fraction in dairy cows supplemented with fat sources

The objective of this study was to evaluate the use of fat sources in rations for lactating cows on the productive performance and composition of milk protein fraction. Twelve Holstein cows were used, grouped in three balanced 4 × 4 Latin squares, fed with the following rations: control; refined soybean oil; whole raw soybean; and calcium salts of unsaturated fatty acid (Megalac-E). Dry matter and nutrient intake, and daily milk production were evaluated. The samples used to analyze milk composition were collected in two alternate days and were obtained from two daily milking. Milk composition and total nitrogen, non-protein nitrogen and non-casein nitrogen ratios were analyzed. The casein, serum protein and true protein ratios were obtained by difference. Dry matter and nutrient intakes were lower when cows received the diet containing calcium salts of fatty acids, in relation to the control diet. Among the diets with fat sources, the one with whole raw soybean and calcium salts decreased milk production. There was no effect of fat sources added to the diet on crude protein, non-protein nitrogen, non-casein nitrogen, true protein, casein, casein/milk true protein ratio and serum protein. Similarly, the experimental diets did not influence the protein fractions when expressed in percentage of milk crude protein. The utilization of fat sources in diets changes milk production and composition of lactating cows, but does not influence the composition of milk protein fractions.

Effect of the kappa-casein gene polymorphism, breed and seasonality on physicochemical characteristics, composition and stability of bovine milk

The objective of this study was to evaluate the effect of genetic polymorphism of kappa-casein, breed and seasonality on the physicochemical characteristics, composition and stability of milk in commercial dairy herds. A total of 879 milk and blood samples were collected from 603 Holstein and 276 Girolando cows, obtained during rainy and dry seasons. Milk samples were analyzed to determine the physicochemical characteristics, composition and ethanol stability, while blood samples were subjected to polymerase chain reaction to identify the kappa-casein genotype. The frequencies of genotypes AA, AB and BB of k-casein were respectively, 66.83, 31.84 and 1.33% for Holstein, and 71.38, 27.90 and 0.72% for the Girolando cows, respectively. The A allele was more frequent than the B allele, both for Holstein (0.827 and 0.173) and Girolando cows (0.853 and 0.147), respectively. Cows of AB and BB genotypes showed a higher milk fat content compared to the AA genotype. There was an interaction between breed and seasonality on the concentration of milk urea with higher values for Holstein and Girolando cows in the rainy and dry season, respectively. The levels of lactose, total solids, crude protein, true protein, casein and the casein:true protein ratio were higher during the dry season, while during the rainy season, the somatic cell count and milk urea concentration were higher. There was no association between milk stability and k-casein genotypes, but Holstein cows showed higher milk stability than Girolando cows, and milk was more stable during the rainy season than during the dry season.