Biological and structural characterization of a new PLA(2) from the Crotalus durissus collilineatus venom

In the present article we report on the biological characterization and amino acid sequence of a new basic Phospholipases A(2) (PLA(2)) isolated from the Crotalus durissus collilineatus venom (Cdcolli F6), which showed the presence of 122 amino acid residues with a pI value of 8.3, molecular mass of 14 kDa and revealed an amino acid sequence identity of 80% with crotalic PLA(2)s such as Mojave B, Cdt F15, and CROATOX. This homology, however, dropped to 50% if compared to other sources of PLA(2)s such as from the Bothrops snake venom. Also, this PLA(2) induced myonecrosis, although this effect was lower than that of BthTx-I or whole crotoxin and it was able to induce a strong blockage effect on the chick biventer neuromuscular preparation, independently of the presence of the acid subunid (crotapotin). The neurotoxic effect was strongly reduced by pre-incubation with heparin or with anhydrous acetic acid and rho-BPB showed a similar reduction. The rho-BPB did not reduce significantly the myotoxic activity induced by the PLA(2), but the anhydrous acetic acid treatment and the pre-incu-bation of PLA(2) with heparin reduced significantly its effects. This protein showed a strong antimicrobial activity against Xanthomonas axonopodis passiflorae (Gram-negative), which was drastically reduced by incubation of this PLA(2) with rho-BPB, but this effect was marginally reduced after treatment with anhydrous acetic acid. Our findings here allow to speculate that basic amino acid residues on the C-terminal and molecular regions near catalytic site regions such as Calcium binding loop or rho-wing region may be involved in the binding of this PLA(2) to the molecular receptor to induce the neurotoxic effect. The bactericidal effect, however, was completely dependent on the enzymatic activity of this protein.

Diversity of phytoseiid mites (Acari: Mesostigmata: Phytoseiidae) in the Atlantic Forest of São Paulo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Morphological, biological and molecular characterization of three strains of Trypanosoma cruzi Chagas, 1909 (Kinetoplastida, Trypanosomatidae) isolated from Triatoma sordida (Stal) 1859 (Hemiptera, Reduviidae) and a domestic cat

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Leaf anatomy as a contribution to the taxonomy of Salacioideae N.Hall, ex Thorne & Reveal (Celastraceae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Pratylenchus jaehni sp n. from citrus in Brazil and its relationship with P-coffeae and P-loosi (Nematoda : Pratylenchidae)

A lesion nematode population infecting citrus in the state of São Paulo, Brazil is described and named Pratylenchus jaehni sp. n. Biological, molecular and morphological characteristics of this new species are compared with those of the morphologically similar P. coffeae and P. loosi. Results of mating experiments showed that R jaehni is reproductively isolated from P coffeae. Molecular (D2/D3 DNA sequences) dissimilarities among P. jaehni sp, n., P. coffeae and P. loosi were documented in a previous study. The morphology of seven R coffeae populations from tropical America and eastern Java and a P loosi population from Sri Lanka is used for comparison with the morphology of P. jaehni sp. n. Pratylenchus jaehni differs from R coffeae and P. loosi by only a few morphological ;characters of the females. The mean values of stylet length, stylet knob height, and vulva position are smaller (less than or equal to15 vs greater than or equal to15 mum, less than or equal to2.7 vs greater than or equal to2.7 mum, less than or equal to79 vs greater than or equal to79%) than those in P coffeae and P loosi. The tail terminus is usually subhemispherical and smooth in P jaehni sp. n.. whereas it is commonly truncate and indented in most P. coffeae populations and bluntly or finely pointed in P. loosi. Because of the morphological similarities among P. jaehni sp. n., P. coffeae and P. loosi, examination of at least ten specimens is required to obtain a reliable diagnosis based on morphology. Nineteen morphometric parameters for P. jaehni sp. n. and P. coffeae ranged from 0-13% smaller in fixed than in live specimens.

Re-Os isotope and highly siderophile element systematics of the Parana continental flood basalts (Brazil)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Environment for teaching and development of mobile robot systems

Using robots for teaching is one approach that has gathered good results on Middle-School, High-School and Universities. Robotics gives chance to experiment concepts of a broad range of disciplines, principally those from Engineering courses and Computer Science. However, there are not many kits that enables the use of robotics in classroom. This article describes the methodologies to implement tools which serves as test beds for the use of robotics to teach Computer Science and Engineering. Therefore, it proposes the development of a flexible, low cost hardware to integrate sensors and control actuators commonly found on mobile robots, the development of a mobile robot device whose sensors and actuators allows the experimentation of different concepts, and an environment for the implementation of control algorithms through a computer network. This paper describes each one of these tools and discusses the implementation issues and future works. © 2010 IEEE.

Initial description of the phylogeography, population structure and genetic diversity of Atlantic spotted dolphins from Brazil and the Caribbean, inferred from analyses of mitochondrial and nuclear DNA

We provide initial information regarding the population structure and genetic diversity of Stenella frontalis from the Caribbean and southeastern Brazil from analyses of mitochondrial control region sequences and sequences from the first intron of the α-lactalbumin gene. Comparisons with previously described S. frontalis sequences showed a high number of haplotypes shared between populations throughout their distribution range. High diversity was found for southeastern Brazil and Caribbean samples, and population structure analyses indicate significant differentiation among population units at the FST level, but not at the ΦST level. Significant differentiation at the FST level was found between the Caribbean population unit and all other populations units. These results suggest historical or present connectivity between the Azores and Madeira and the southeastern Brazil groups and population differentiation between the Caribbean and southeastern Brazil, supporting the notion of two separate stocks in the waters around the Atlantic coast of South America. © 2013 Elsevier Ltd.

Design, synthesis and biological evaluation of new aryl thiosemicarbazone as antichagasic candidates

The present work reports on the synthesis, biological assaying and docking studies of a series of 12 aryl thiosemicarbazones, which were planned to act over two main enzymes, cruzain and trypanothione reductase. These enzymes are used as targets of trypanocidal activity in Chagas disease control with a minimal mutagenic profile. Three p-nitroaromatic thiosemicarbazones showed high activity against Trypanosoma cruzi in in vitro assays (IC50 < 57 μM), and no mutagenic profile was observed in micronucleous tests. Although the in vitro inhibition test showed that 10-μM doses of eight compounds inhibited cruzain activity, no correlation was found between cruzain inhibition and trypanocidal activity. © 2013 Elsevier Masson SAS. All rights reserved.

Brazilian Angiostrongylus cantonensis haplotypes, ac8 and ac9, have two different biological and morphological profiles

Angiostrongylus cantonensis is the etiologic agent of eosinophilic meningoencephalitis in humans. Cases have been recorded in many parts of the world, including Brazil. The aim of this study was to compare the differences in the biology and morphology of two different Brazilian haplotypes of A. : ac8 and ac9. A significantly larger number of L1 larvae eliminated in the faeces of rodents at the beginning of the patent period was observed for ac9 haplotype and compared to the total of L1 larvae eliminated, there was a significant difference between the two haplotypes. The ac9 haplotype showed a significant difference in the proportion of female and male specimens (0.6:1), but the same was not observed for ac8 (1.2:1). The morphometric analysis showed that male and female specimens isolated from ac8 haplotype were significantly larger with respect to body length, oesophagus length, spicule length (male) and distance from the anus to the rear end (female) compared to specimens from ac9. The morphological analysis by light microscopy showed little variation in the level of bifurcations at the lateral rays in the right lobe of the copulatory bursa between the two haplotypes. The biological, morphological and morphometric variations observed between the two haplotypes agree with the observed variation at the molecular level using the cytochrome oxidase subunit I marker and reinforce the possible influence of geographical isolation on the development of these haplotypes.

Effectiveness and biological compatibility of different generations of dentin adhesives

Besides possessing good mechanical properties, dental materials should present a good biological behavior and should not injure the involved tissues. Bond strength and biocompatibility are both highly significant properties of dentin adhesives. For that matter, these properties of four generations of adhesive systems (Multi-Purpose/Single Bond/SE Plus/Easy Bond) were evaluated.Eighty bovine teeth had their dentin exposed (500- and 200-mu m thickness). Adhesive was applied on the dentin layer of each specimen. Following that, the microshearing test was performed for all samples. A dentin barrier test was used for the cytotoxicity evaluation. Cell cultures (SV3NeoB) were collected from testing materials by means of 200- or 500-mu m-thick dentin slices and placed in a cell culture perfusion chamber. Cell viability was measured 24 h post-exposition by means of a photometrical test (MTT test).The best bonding performance was shown by the single-step adhesive Easy Bond (21 MPa, 200 mu m; 27 MPa, 500 mu m) followed by Single Bond (15.6 MPa, 200 mu m; 23.4 MPa, 500 mu m), SE Plus (18.2 MPa, 200 mu m; 20 MPa, 500 mu m), and Multi-Purpose (15.2 MPa, 200 mu m; 17.9 MPa, 500 mu m). Regarding the cytotoxicity, Multi-Purpose slightly reduced the cell viability to 92 % (200 mu m)/93 % (500 mu m). Single Bond was reasonably cytotoxic, reducing cell viability to 71 % (200 mu m)/64 % (500 mu m). The self-etching adhesive Scotchbond SE decreased cell viability to 85 % (200 mu m)/71 % (500 mu m). Conversely, Easy Bond did not reduce cell viability in this test, regardless of the dentin thickness.Results showed that the one-step system had the best bond strength performance and was the least toxic to pulp cells. In multiple-step systems, a correct bonding technique must be done, and a pulp capping strategy is necessary for achieving good performance in both properties.The study showed a promising system (one-step self-etching), referring to it as a good alternative for specific cases, mainly due to its technical simplicity and good biological responses.

New species of Daidalotarsonemus and Excelsotarsonemus (Acari, Tarsonemidae) from the Brazilian rainforest

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

Conventional versus biological therapy for prevention of postoperative endoscopic recurrence in patients with Crohn's disease: an international, multicenter, and observational study

Postoperative endoscopic recurrence (PER) occurs in nearly 80% of patients 1 year after ileocecal resection in patients with Crohn's disease (CD). Biological agents were more effective in reducing the rates of PER in comparison with conventional therapy, in prospective trials. The aim of this study was to compare the PER rates of biological versus conventional therapy after ileocecal resections in patients with CD in real-world practice. The MULTIPER (Multicenter International Postoperative Endoscopic Recurrence) database is a retrospective analysis of PER rates in CD patients after ileocecal resection, from 7 referral centers in 3 different countries. All consecutive patients who underwent ileocecal resections between 2008 and 2012 and in whom colonoscopies had been performed up to 12 months after surgery, were included. Recurrence was defined as Rutgeerts' score ≥i2. The patients were allocated to either biological or conventional therapy after surgery, and PER rates were compared between the groups. Initially, 231 patients were evaluated, and 63 were excluded. Of the 168 patients in the database, 96 received anti-tumor necrosis factor agents and 72 were treated with conventional therapy after resection. The groups were comparable regarding age, gender, and perianal disease. There was longer disease duration, more previous resections, and more open surgical procedures in patients on biologicals postoperatively. PER was identified in 25/96 (26%) patients on biological therapy and in 24/72 (33.3%) patients on conventional therapy (P=0.310). In this retrospective observational analysis from an international database, no difference was observed between biological and conventional therapy in preventing PER after ileocecal resections in CD patients.

Sistemática e filogenia do fungo parasita Escovopsis associado às formigas Attini

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

On the formation of carbonate adducts of fatty alcohols, sterols, and sugars in biological conditions

The formation and properties of carbonate adducts of some organic hydroxy compounds in aqueous medium were investigated. Fatty alcohols and sugars were chosen as representative classes of biological interest, and the medium was carbonated aqueous solution with pH ranging from 3.0 to 8.3. Capillary electrophoresis with two capacitively coupled contactless conductivity detectors (C4Ds) was used for quantitation and to obtain the mobility of the monoalkyl carbonates (MACs), which were used to determine the equilibrium and kinetic constants of the reaction as well as the diffusion coefficients. For increasing chain length of the alcohols, the equilibrium constant tends to the unit, which suggests that fatty alcohols can form the corresponding MACs. The formation of MACs for cyclohexanol and cyclopentanol also suggest the existence of similar species for sterols. Carbonate adducts of fructose, glucose, and sucrose were also detected, which suggests that these counterparts of the well-known phosphates can also occur in the cytosol. Our calculations suggest that one in 1000 to one in 10 000 molecules of these hydroxy compounds would be available as the corresponding MAC in such a medium. Experiments carried out at pH values less than 3.0 showed that there is a catalytic effect of hydronium on the interconversion of bicarbonate and a MAC. Taking into account the great number of hydroxy compounds similar to the ones investigated and that bicarbonate is ubiquitous in living cells, one can anticipate the existence of a whole new class of carbonate adducts of these metabolites.