Morphological characterisation of five brazilian species of Fidicinoides (Hemiptera: Cicadidae)

The objective of this study was to describe and illustrate the morphological characteristics of some species of Brazilian Fidicinoides to aid in their identification. Descriptions and illustrations are given of the head, thorax, abdomen, right forewing and the last urostemite of the male of the Fidicinoides besti, Fidicinoides brunnea, Fidicinoides duckensis, Fidicinoides pseudethelae and Fidicinoides sucinalae species. The main diagnostic characteristics of these species are markings on pronotum and/or mesonotum and male stemite VIII characteristics.

Molecular characterisation of Bartonella species in cats from Sao Luis, state of Maranhao, north-eastern Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Purification and structural characterisation of (1 -> 3 ; 1 -> 6)-beta-D-glucans (botryosphaerans) from Botryosphaeria rhodina grown on sucrose and fructose as carbon sources: a comparative study

Two botryosphaerans, exopolysaccharides (EPS) secreted by the ascomyceteous fungus Botryosphaeria rhodina, when grown on sucrose and fructose as sole carbon sources, were structurally compared after their isolation from the culture medium. Both EPS were submitted to trypsin digestion, and eluted as a single peak on gel filtration. Total acid hydrolysis yielded only glucose, and data from methylation analysis and Smith degradation indicated that both EPS constituted a main chain of glucopyranosyl beta(1 -> 3) linkages substituted at O-6. The products obtained after partial acid hydrolysis demonstrated side chains consisting of glucosyl- and gentiobiosyl- linked beta(1 -> 6) residues. C-13-NMR spectroscopy studies showed that all glucosidic linkages were of the beta-configuration. The carbon source affected the side chain structures of botryosphaeran but not the main chain makeup. Sucrose produced less branching (21%) than fructose (31%). (c) 2005 Published by Elsevier Ltd.

Preparation and characterisation of Dextran-70 hydrogel for controlled release of praziquantel

Um hidrogel foi desenvolvido a partir de dextrano 70 kDa (DEX-70) e praziquantel incorporado (PZQ) como fármaco modelo. Propriedades biofarmacêuticas, como solubilidade e velocidade de dissolução, foram analisadas no desenvolvimento do hidrogel. Além disso, o hidrogel também foi caracterizado por espectroscopia na região do infravermelho e calorimetria diferencial exploratória (DSC). Testes da taxa de intumescimento mostraram que o hidrogel intumesce lentamente, embora tenha sido mais rápido do que a taxa do polímero livre. Nos testes de dissolução, o hidrogel liberou o fármaco lenta e continuamente. Esta liberação lenta foi semelhante a observada nos testes de intumescimento e resultou em uma liberação controlada do fármaco. Assim, o dextrano 70 kDa é um polímero adequado para o desenvolvimento de hidrogéis como veículos para a liberação controlada de fármacos.

On the characterisation of electrically stressed polyethylene before and after chemical treatment

Low-density polyethylene (LDPE) was characterised for its dielectric and electrical properties before and after chemical treatment. A reduction in the permittivity and dielectric loss was observed in the polymer after treatment with hexane. The intensity in the Raman Spectrum in the disordered longitudinal acoustic mode region (DLAM) also was reduced due to a hexane treatment. Using thermally stimulated discharge current (TSDC) and laser-intensity-modulated method (LIMM) techniques it was observed that charge injection can be enhanced in the polymer matrix in the empty sites, created by the removal of the low molecular weight impurities with chemical treatment. (C) 2002 Kluwer Academic Publishers.

Genetic characterisation of Giardia duodenalis in dairy cattle in Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Functional characterisation of alpha(1)-adrenoceptors in denervated rat vas deferens

We investigated whether or not surgical denervation of the rat vas deferens changes the alpha(1)-adrenoceptor subtypes involved in the contractions to noradrenaline. Denervated vas deferens was approximate to22 times more sensitive to noradrenaline (pD(2)=7.35 +/- 0.04) than control vas (pD(2)= 6.01 +/- 0.03). This difference in noradrenaline potency was eliminated when cocaine (6 muM) was added to control vas (pD(2)=7.22 +/- 0.04). The noradrenaline-induced contractions of control and denervated vas deferens were insensitive to the alpha(1B)/alpha(1D)-adrenoceptor alkylating agent chloroethylclonidine (100 muM, 45 min). The concentration-response curves to noradrenaline in control and denervated vas deferens were competitively antagonised by prazosin (pA(2)approximate to9.6), WB-4101 (pA(2)approximate to9.5), 5-methyl urapidil (pA(2)approximate to8.4), phentolamine (pA(2)approximate to8.7), yohimbine (pA(2)approximate to6.9), BMY 7378 (pA(2)approximate to6.9) and indoramin (pA(2)approximate to8.7). After the treatment of control and denervated vas deferens with phenoxybenzamine, the partial agonist oxymetazoline antagonised competitively the concentration-response curves to noradrenaline showing pA(2) values approximate to7.4 in both groups. We conclude that noradrenaline-induced contractions in control and denervated rat vas deferens are mediated by alpha(1A)-adrenoceptors and that surgical denervation of the rat vas deferens is not able to change the alpha(1)-adrenoceptor subtypes involved in the contractions to noradrenaline.

Characterisation of protease activity in extracellular products secreted by Giardia duodenalis trophozoites treated with propolis

Results from our laboratory revealed propolis activity on Giardia trophozoites proliferation. Since therapeutic agents can inhibit the activity of proteases related to relevant biologic and physiologic processes of parasites, this study was undertaken to characterise the proteolytic activity of excretory/secretory products (ESP) of trophozoites treated with propolis. ESP was obtained from culture supernatants of trophozoites exposed to 250 and 500 mu g mL(-1) of propolis. ESP were tested in sodium dodecyl sulfate-polyacrylamide gel electrophoresis for the protein profiles and the protease activity was assayed in gelatin-containing gels. Synthetic inhibitors were used to characterise the protease classes. Treated and non-treated ESP showed a similar protein and hydrolysis pattern. A simple pattern of protein composed by five evident bands of approximately 167, 132, 79, 61 and 51 kDa was found, and the zymograms comprised hydrolysis zones distributed from > 170 to 23 kDa. No inhibition was seen on protease activity of propolis-treated trophozoites, whose hydrolysis pattern was similar to control. One may conclude that both ESP degraded gelatin and the activity was predominantly due to cysteine proteases. Although propolis had no effect on the proteolytic activity, further studies could identify the active constituents responsible for propolis antigiardial activity and their mechanisms of action.

Characterisation of the chromosome fusions in Oreochromis karongae

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Surface characterisation of V(2)O(5)/TiO(2) catalytic system

Samples of the V(2)O(5)/TiO(2) system were prepared by the sol-gel method and calcined at different temperatures. Surface species of vanadium, their dispersion, as well as the structural evolution of the system were analysed by XRD, Raman, EPR, and XPS techniques. The results of XRD showed the evolution of TiO(2) from anatase phase to rutile. phase. The Raman spectra for calcination temperatures up to 500 degreesC showed a good dispersion of vanadium over titania in the form of monomeric vanadyl groups (V(4+)) and polymeric vanadates (V(5+)). At least three families of V4+ ions were identified by EPR investigations. Two kinds of isolated V(4+) species are placed in sites of octahedral symmetry, substituting Ti(4+) in the rutile phase. The third is formed by pairs of V(4+) species on the surface of titania. Above 500 degreesC part of superficial V(4+) is inserted into the,matrix of titania and part is oxidized to V(5+). The XPS results showed that the V/Ti ratio rises with increasing calcination temperature, indicating a smaller dispersion of vanadium.

Cytogenetic characterisation of the ornamental freshwater fish, Piabucus melanostomus (Iguanodectinae) from Brazilian wetlands and its relation with species of Characidae basal group

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Preparation of zinc sodium polyphosphates glasses from coacervates precursors. Characterisation of the obtained glasses, and their applications

A soft chemistry route is described to obtain glasses in the P2O5-Na2O-ZnO-H2O. It is based on the addition of zinc salts to coacervates prepared from sodium polyphosphate. The processing of these coacervates leads to polyphosphate glasses with the same properties as those of glasses prepared in the classical way. So far, little work has been implemented in this system using 'coacervate route'. However, it makes an attractive method for coating and joining processes on the industrial scale. As the anion associated to zinc may take part in the adhesion mechanism, coacervate formation has been studied using zinc chloride, nitrate and sulphate as starting materials. The physical properties of the glasses obtained by this method are reported and potential applications of zinc and silver coacervate are described. (C) 2002 Academie des sciences / Editions scientifiques et medicales Elsevier SAS.

Characterisation of sugar cane combustion particles in the Araraquara region, Southeast Brazil

Biomass burning is an important primary and secondary source of aerosol particles. The presence of carbonaceous particles in the respirable size range makes the study of this fraction important in view of possible health and climatic effects. The annual burning of sugar cane plantations causes emission of huge amounts of pyrogenic particles. Aerosol samples were collected in Araraquara city, São Paulo state, Brazil, during the harvest season for fine and coarse particles and bulk; they were analysed by electron-probe microanalysis, including facilities for low-Z element determination (low-Z EPMA) and by energy-dispersive X-ray fluorescence (EDXRF), in order to investigate the elemental composition of individual particles and bulk samples, respectively. Numerical analysis of the EPMA results by hierarchical clustering shows high contributions of carbonaceous particles that can be distinguished mainly in two different types: biogenic and carbon-rich. Additionally, two significant contributions of aluminosilicate particles were identified: as rather pure aluminosilicates or mixed with carbonaceous species. The EDXRF results are compatible with those of aerosol particles in Amazon, which is nowadays one of the main sources of biogenic particles in the world.

Isolation and characterisation of cycloheximide sensitive mutants of Aspergillus nidulans

Aspergillus nidulans is a non-pathogenic fungus with well-developed genetics which provides an excellent model system for studying different aspects of drug resistance in filamentous fungi. As a preliminary step to characterizing genes that confer pleiotropic drug resistance in Aspergillus, we isolated cycloheximide-sensitive mutants of A. nidulans, which is normally resistant to this: drug. The rationale for this approach is to identify gents whose products are important for drug resistance by analysing mutations that alter the resistance/sensitivity status of the cell. Fifteen cycloheximide-sensitive (named scy for sensitive to cycloheximide) mutants of A, nidulans were isolated and genetically characterised. Each scy mutant was crossed with the wild-type strain and five of the crosses gave 50% cycloheximide-sensitive progeny suggesting that they carry a single mutation required for cycloheximide sensitivity. We examined ten sep mutants for resistance/sensitivity to other drugs or stress agents with different and/or the same mechanism of action, Sis of these mutants exhibited other altered resistance/sensitivity phenotypes which were linked to the cycloheximide sensitivity, These six mutants were analyzed by pairwise crosses and found to represent six linkage groups, named scyA-F. One of the mutants showed fragmentation of its vacuolar system and, in addition, its growth was osmotic, low-pi-II and oxidative-stress sensitive.

The characterisation of the protective film formed by benzotriazole on the 90/10 copper-nickel alloy surface in H2SO4 media

The nature of the protective film formed by benzotriazole (BTAH) on the surface of the 90/10 CuNi alloy in deaerated 0.5 mol L-1 H2SO4 solution containing Fe(III) ions as oxidant was investigated by weight-loss, calorimetric measurements, and by surface-enhanced Raman spectroscopy (SERS). The SERS measurements show that the protective film is composed by the [Cu(I)BTA](n), polymeric complex and that the BTAH molecules are also adsorbed on the electrode surface. A modification of the BET isotherm for adsorption of gases ill solids is proposed to describe the experimental results obtained from weight-loss experiments that suggest an adsorption in multilayers. Electrochemical studies of copper and nickel in 0.5 mol L-1 H2SO4 in presence and absence of BTAH have also been made as an aid to interpret the results. The calculated adsorption free energy of the cuprous benzotriazolate on the surface of the alloy is in accordance with the value for pure copper. (C) 2007 Elsevier Ltd. All rights reserved.