Cyclooligomerisation of azido-alkyne-functionalised sugars: synthesis of 1,6-linked cyclic pseudo-galactooligosaccharides and assessment of their sialylation by Trypanosoma cruzi trans-sialidase

Cyclic pseudo-galactooligosaccharides were synthesized by cyclooligomerisation of isomeric azido-alkyne derivatives of beta-D-galactopyranose under Cu(I)-catalysed azide-alkyne 1,3-dipolar cycloaddition reaction conditions. The principal products isolated were cyclic dimers and trimers, with lower amounts of cyclic tetramer and pentamer also evident in some cases. Molecular mechanics calculations suggest very compact but flexible structures for the cyclic trimers, with secondary OH groups exposed outside the macrocycle and available for enzymatic glycosylation. The cyclic dimers and trimers represent a new type of acceptor substrate for Trypanosoma cruzi trans-sialidase, giving rise to doubly and triply sialylated glycomacrocycles, respectively.

Cell-Free Antigens from Paracoccidioides brasiliensis Drive IL-4 Production and Increase the Severity of Paracoccidioidomycosis

The thermally dimorphic fungus Paracoccidioides brasiliensis (Pb) is the causative agent of paracoccidioidomycosis (PCM), one of the most frequent systemic mycosis that affects the rural population in Latin America. PCM is characterized by a chronic inflammatory granulomatous reaction, which is consequence of a Th1-mediated adaptive immune response. In the present study we investigated the mechanisms involved in the immunoregulation triggered after a prior contact with cell-free antigens (CFA) during a murine model of PCM. The results showed that the inoculation of CFA prior to the infection resulted in disorganized granulomatous lesions and increased fungal replication in the lungs, liver and spleen, that paralleled with the higher levels of IL-4 when compared with the control group. The role of IL-4 in facilitating the fungal growth was demonstrated in IL-4-deficient- and neutralizing anti-IL-4 mAb-treated mice. The injection of CFA did not affect the fungal growth in these mice, which, in fact, exhibited a significant diminished amount of fungus in the tissues and smaller granulomas. Considering that in vivo anti-IL-4-application started one week after the CFA-inoculum, it implicates that IL-4-CFA-induced is responsible by the mediation of the observed unresponsiveness. Further, the characterization of CFA indicated that a proteic fraction is required for triggering the immunosuppressive mechanisms, while glycosylation or glycosphingolipids moieties are not. Taken together, our data suggest that the prior contact with soluble Pb antigens leads to severe PCM in an IL-4 dependent manner.

Therapeutic Efficacy of Cintredekin Besudotox (IL13-PE38QQR) in Murine Lung Fibrosis Is Unaffected by Immunity to Pseudomonas aeruginosa Exotoxin A

Background: We have previously explored a therapeutic strategy for specifically targeting the profibrotic activity of IL-13 during experimental pulmonary fibrosis using a fusion protein comprised of human IL-13 and a mutated form of Pseudomonas aeruginosa exotoxin A (IL13-PE) and observed that the intranasal delivery of IL13-PE reduced bleomycin-induced pulmonary fibrosis through its elimination of IL-13-responsive cells in the lung. The aim of the present study was to determine whether the presence of an immune response to P. aeruginosa and/or its exotoxin A (PE) would diminish the anti-fibrotic properties of IL13-PE. Methodology/Principal Findings: Fourteen days after P. aeruginosa infection, C57BL/6 mice were injected with bleomycin via the intratracheal route. Other groups of mice received 4 doses of saline or IL13-PE by either intranasal or intraperitoneal application, and were challenged i.t. with bleomycin 28 days later. At day 21 after bleomycin, all mice received either saline vehicle or IL13-PE by the intranasal route and histopatological analyses of whole lung samples were performed at day 28 after bleomycin. Intrapulmonary P. aeruginosa infection promoted a neutralizing IgG2A and IgA antibody response in BALF and serum. Surprisingly, histological analysis showed that a prior P. aeruginosa infection attenuated the development of bleomycin-induced pulmonary fibrosis, which was modestly further attenuated by the intranasal administration of IL13-PE. Although prior intranasal administration of IL13-PE failed to elicit an antibody response, the systemic administration of IL13-PE induced a strong neutralizing antibody response. However, the prior systemic sensitization of mice with IL13-PE did not inhibit the anti-fibrotic effect of IL13-PE in fibrotic mice. Conclusions: Thus, IL13-PE therapy in pulmonary fibrosis works regardless of the presence of a humoral immune response to Pseudomonas exotoxin A. Interestingly, a prior infection with P. aeruginosa markedly attenuated the pulmonary fibrotic response suggesting that the immune elicitation by this pathogen exerts anti-fibrotic effects.

New Genotype of Dengue Type 3 Virus Circulating in Brazil and Colombia Showed a Close Relationship to Old Asian Viruses

Dengue type 3 genotype V viruses have been recently detected in Brazil and Colombia. In this study, we described another Brazilian isolate belonging to this genotype. Phylogenetic analysis including dengue type 3 viruses isolated worldwide showed that Brazilian and Colombian viruses were closely related to viruses isolated in Asia more than two decades ago. The characteristic evolutionary pattern of dengue type 3 virus cannot explain the close similarity of new circulating viruses with old viruses. Further studies are needed to confirm the origin of the new dengue type III genotype circulating in Brazil and Colombia.

A New Baurusuchid (Crocodyliformes, Mesoeucrocodylia) from the Late Cretaceous of Brazil and the Phylogeny of Baurusuchidae

Background: Baurusuchidae is a group of extinct Crocodyliformes with peculiar, dog-faced skulls, hypertrophied canines, and terrestrial, cursorial limb morphologies. Their importance for crocodyliform evolution and biogeography is widely recognized, and many new taxa have been recently described. In most phylogenetic analyses of Mesoeucrocodylia, the entire clade is represented only by Baurusuchus pachecoi, and no work has attempted to study the internal relationships of the group or diagnose the clade and its members. Methodology/Principal Findings: Based on a nearly complete skull and a referred partial skull and lower jaw, we describe a new baurusuchid from the Vale do Rio do Peixe Formation (Bauru Group), Late Cretaceous of Brazil. The taxon is diagnosed by a suite of characters that include: four maxillary teeth, supratemporal fenestra with equally developed medial and anterior rims, four laterally visible quadrate fenestrae, lateral Eustachian foramina larger than medial Eustachian foramen, deep depression on the dorsal surface of pterygoid wing. The new taxon was compared to all other baurusuchids and their internal relationships were examined based on the maximum parsimony analysis of a discrete morphological data matrix. Conclusion: The monophyly of Baurusuchidae is supported by a large number of unique characters implying an equally large morphological gap between the clade and its immediate outgroups. A complex phylogeny of baurusuchids was recovered. The internal branch pattern suggests two main lineages, one with a relatively broad geographical range between Argentina and Brazil (Pissarrachampsinae), which includes the new taxon, and an endemic clade of the Bauru Group in Brazil (Baurusuchinae).

Ecdysteroid-Dependent Expression of the Tweedle and Peroxidase Genes during Adult Cuticle Formation in the Honey Bee, Apis mellifera

Cuticle renewal is a complex biological process that depends on the cross talk between hormone levels and gene expression. This study characterized the expression of two genes encoding cuticle proteins sharing the four conserved amino acid blocks of the Tweedle family, AmelTwdl1 and AmelTwdl2, and a gene encoding a cuticle peroxidase containing the Animal haem peroxidase domain, Ampxd, in the honey bee. Gene sequencing and annotation validated the formerly predicted tweedle genes, and revealed a novel gene, Ampxd, in the honey bee genome. Expression of these genes was studied in the context of the ecdysteroid-coordinated pupal-to-adult molt, and in different tissues. Higher transcript levels were detected in the integument after the ecdysteroid peak that induces apolysis, coinciding with the synthesis and deposition of the adult exoskeleton and its early differentiation. The effect of this hormone was confirmed in vivo by tying a ligature between the thorax and abdomen of early pupae to prevent the abdominal integument from coming in contact with ecdysteroids released from the prothoracic gland. This procedure impaired the natural increase in transcript levels in the abdominal integument. Both tweedle genes were expressed at higher levels in the empty gut than in the thoracic integument and trachea of pharate adults. In contrast, Ampxd transcripts were found in higher levels in the thoracic integument and trachea than in the gut. Together, the data strongly suggest that these three genes play roles in ecdysteroid-dependent exoskeleton construction and differentiation and also point to a possible role for the two tweedle genes in the formation of the cuticle (peritrophic membrane) that internally lines the gut.

Electrochemical Evidence of Strong Electronic Interaction of PtRu on Carbon Nanotubes with High Density of Defects

We show that carbon nanotubes (CNTs) with high density of defects can present a strong electronic interaction with nanoparticles of Pt-Ru with average particle size of 3.5 +/- 0.8 nm. Depending on the Pt-Ru loading on the CNTs, CO and methanol oxidation reactions suggest there is a charge transfer between Pt-Ru that in turn provokes a decrease in the electronic interaction taking place between Ru and Pt in the PtRu alloy. The CO stripping potentials were observed at about 0.65 and 0.5 V for Pt-Ru/CNT electrodes with Pt-Ru loadings of 10 and 20, and 30 wt %, respectively. (C) 2008 The Electrochemical Society. [DOI: 10.1149/1.2990222] All rights reserved.

Time Changes with the Embodiment of Another's Body Posture

The aim of the present study was to investigate whether the perception of presentation durations of pictures of different body postures was distorted as function of the embodied movement that originally produced these postures. Participants were presented with two pictures, one with a low-arousal body posture judged to require no movement and the other with a high-arousal body posture judged to require considerable movement. In a temporal bisection task with two ranges of standard durations (0.4/1.6 s and 2/8 s), the participants had to judge whether the presentation duration of each of the pictures was more similar to the short or to the long standard duration. The results showed that the duration was judged longer for the posture requiring more movement than for the posture requiring less movement. However the magnitude of this overestimation was relatively greater for the range of short durations than for that of longer durations. Further analyses suggest that this lengthening effect was mediated by an arousal effect of limited duration on the speed of the internal clock system.

Sentidos de biblioteca escolar no discurso da Ciência da Informação

This paper approaches the meaning of school library through a multidisciplinary perspective including the Information Science, the French Discourse Analysis and Education. It aims to understand how the imaginary about this institution is constructed, in the area of Information Science, and to reflect on how this symbol is influenced by the social, historical and ideological conditions of discourse production and by memory. To develop these questions, first of all, it accomplishes a brief review of the literature concerning the French Discourse Analysis; then it analyzes discourses about the school library in nineteen scientific documents ( articles and works presented at scientific events), and also the different meanings of this information unit, its objectives and its ways of constituting the social imaginary. It is concluded that the information professionals could and should collaborate to the spreading of new practices and meaning in the school library.

The non-equilibrium nature of culinary evolution

Food is an essential part of civilization, with a scope that ranges from the biological to the economic and cultural levels. Here, we study the statistics of ingredients and recipes taken from Brazilian, British, French and Medieval cookery books. We find universal distributions with scale invariant behaviour. We propose a copy-mutate process to model culinary evolution that fits our empirical data very well. We find a cultural 'founder effect' produced by the non-equilibrium dynamics of the model. Both the invariant and idiosyncratic aspects of culture are accounted for by our model, which may have applications in other kinds of evolutionary processes.

Indications of Conical Emission of Charged Hadrons at the BNL Relativistic Heavy Ion Collider

Three-particle azimuthal correlation measurements with a high transverse momentum trigger particle are reported for pp, d + Au, and Au + Au collisions at root(S)NN = 200 GeV by the STAR experiment. Dijet structures are observed in pp, d + Au and peripheral Au + Au collisions. An additional structure is observed in central Au + Au data, signaling conical emission of correlated charged hadrons. The conical emission angle is found to be theta = 1.37 +/- 0.02(stat)(-0.07)(+0.06)(syst), independent of p perpendicular to.

System-Size Independence of Directed Flow Measured at the BNL Relativistic Heavy-Ion Collider

We measure directed flow (v(1)) for charged particles in Au + Au and Cu + Cu collisions at root s(NN) = 200 and 62.4 GeV, as a function of pseudorapidity (eta), transverse momentum (p(t)), and collision centrality, based on data from the STAR experiment. We find that the directed flow depends on the incident energy but, contrary to all available model implementations, not on the size of the colliding system at a given centrality. We extend the validity of the limiting fragmentation concept to v(1) in different collision systems, and investigate possible explanations for the observed sign change in v(1)(p(t)).

Forward Neutral-Pion Transverse Single-Spin Asymmetries in p plus p Collisions at s=200 GeV

We report precision measurements of the Feynman x (x(F)) dependence, and first measurements of the transverse momentum (p(T)) dependence, of transverse single-spin asymmetries for the production of pi(0) mesons from polarized proton collisions at s=200 GeV. The x(F) dependence of the results is in fair agreement with perturbative QCD model calculations that identify orbital motion of quarks and gluons within the proton as the origin of the spin effects. Results for the p(T) dependence at fixed x(F) are not consistent with these same perturbative QCD-based calculations.

Longitudinal double-spin asymmetry for inclusive jet production in (p)over-right-arrow + (p)over-right-arrow collisions at root s=200 GeV

We report a new STAR measurement of the longitudinal double-spin asymmetry A(LL) for inclusive jet production at midrapidity in polarized p+p collisions at a center-of-mass energy of root s = 200 GeV. The data, which cover jet transverse momenta 5 < p(T) < 30 GeV/c, are substantially more precise than previous measurements. They provide significant new constraints on the gluon spin contribution to the nucleon spin through the comparison to predictions derived from one global fit to polarized deep-inelastic scattering measurements. They provide significant new constraints on the gluon spin contribution to the nucleon spin through the comparison to predictions derived from one global fit to polarized deep-inelastic scattering measurements.

Shallow landslide prediction in the Serra do Mar, Sao Paulo, Brazil

Various methods are currently used in order to predict shallow landslides within the catchment scale. Among them, physically based models present advantages associated with the physical description of processes by means of mathematical equations. The main objective of this research is the prediction of shallow landslides using TRIGRS model, in a pilot catchment located at Serra do Mar mountain range, Sao Paulo State, southeastern Brazil. Susceptibility scenarios have been simulated taking into account different mechanical and hydrological values. These scenarios were analysed based on a landslide scars map from the January 1985 event, upon which two indexes were applied: Scars Concentration (SC - ratio between the number of cells with scars, in each class, and the total number of cells with scars within the catchment) and Landslide Potential (LP - ratio between the number of cells with scars, in each class, and the total number of cells in that same class). The results showed a significant agreement between the simulated scenarios and the scar's map. In unstable areas (SF <= 1), the SC values exceeded 50% in all scenarios. Based on the results, the use of this model should be considered an important tool for shallow landslide prediction, especially in areas where mechanical and hydrological properties of the materials are not well known.