Profilin as a severe food allergen in allergic patients overexposed to grass pollen.

BACKGROUND: Profilins are ubiquitous proteins that act as panallergens in sensitized patients, considered to be mild or incomplete food allergens. The aim of the study was to evaluate the role of profilins as severe food allergens in allergic patients overexposed to grass who were referred for severe food reactions and were sensitized to profilins. METHODS: After a careful in vitro screening, 26 patients were included, classified into two groups, mild (17) and severe reactors (9), based on clinical history and subsequently provoked orally with purified profilin in a double-blind placebo-controlled food challenge setup. RESULTS: A significant number of patients presented severe positive food challenge test reactions at low doses of the allergen profilin. Patients prone to suffer from severe reactions had lower IgG4/IgE ratio to major grass allergens than those who did not. CONCLUSION: Profilins are complete food allergens in food-allergic patient populations that are exposed to high levels of grass pollen. This type of patient constitutes an optimal model to understand the link between respiratory and food allergies. The nature of the observed reactions and the low level of allergen eliciting the reactions suggest that intake through the oral mucosa might constitute a relevant route of exposure to food allergens.

Carbon nanofiber growth optimization for their use as electrocatalyst support in proton exchange membrane (PEM) fuel cells.

Carbon nanofiber (CNF) growth by catalytic decomposition of methane in a fixed-bed reactor was studied out to elucidate the influence of some important reaction conditions: temperature, space velocity and reactant partial pressure, in the morphological properties of the carbonaceous material obtained. The main objective is to synthesize a suitable carbonaceous nanomaterial to be used as support in platinum based electrocatalysts for Proton Exchange Membrane Fuel Cells (PEMFC) which improves current carbon blacks. High specific surface area is required in an electrocatalyst support since platinum dispersion is enhanced and so a cost-effective usage and high catalytic activity. Good electrical conductivity of carbon support is also required since the fuel cell power density is improved. With this proposal, characterization was carried out by nitrogen physisorption, XRD, SEM and TPO. The results were analysed by a factorial design and analysis of variance (ANOVA) in order to find an empirical correlation between operating conditions and CNF characteristics. It was found that the highest specific surface area and pore volume were found at 823 K and at a space velocity of 10 L gcat(-1) h(-1). The graphitic character of CNF, which is known to influence the electrical conductivity, presented a maximum value at temperatures between 923 K and 973 K. SEM images showed a narrow size distribution of CNF diameter between 40 and 90 nm and homogeneous appearance.

Study of the surface chemistry of modified carbon nanofibers by oxidation treatments in liquid phase.

Carbon nanofibers (CNF) were grown by thermocatalytic decomposition of methane. Their texture and surface chemistry were modified by different oxidation treatments with HNO3 at different concentrations or a mixture of HNO3-H2SO4 to optimise their ability of dispersing active metal particles, because this material will be used as electrocatalytic support for polymeric electrolyte fuel cells. The effect of liquid phase oxidation on the surface chemistry and the textural properties of the CNF was studied by temperature programmed desorption (TPD), scanning electron microscopy (SEM) and N2-physisorption. Moreover, their thermal stability was studied by temperature programmed oxidation (TPO). During oxidation treatments functional groups were created and their number was function of the oxidation treatment conditions. Results indicated that an increase in severity of the oxidation treatment produces an increase in the number of surface oxygen groups and in the thermal stability. However, a very severe treatment can destroy partially the structure of carbon nanofibers.

Characterization of carbon nanofibers grown over Ni and Ni-cu catalysts.

Carbon nanofibers were obtained by thermo-catalytic decomposition of methane at 700 degrees C over Ni and Ni-Cu catalysts prepared by different methods (co-precipitation, impregnation and fusion) and using either Al or Mg as textural promoter. Characterization of the carbon thus obtained was performed by N2 adsorption isotherms (BET surface area), temperature programmed desorption (TPD), temperature programmed oxidation (TPO), X-ray diffraction, Raman spectrometry, and electron microscopy SEM and TEM. The carbon obtained possesses high crystallinity and poor surface chemistry. The crystallinity is enhanced when using Mg as textural promoter and in the presence of copper. SEM and TEM examinations show that the fibers have fishbone structure and they grow generally from one nickel particle (tip growing) although there are some bidirectional growing. Copper-doping lead to the formation of thicker filaments and promotes the formation of bamboo-like structures. Catalyst particles higher than 100 nm do not promote the formation of nanofibers and the carbon deposits as uniform coatings.

[Acute appendicitis in the elderly patient]. / Apendicitis aguda en el anciano.

Presentation of 55 patients aged more than 65 years, appendectomized with the diagnosis of acute appendicitis. After histological study, we saw 6 normal cecal appendixes (10.9%), so the real number of acute appendicitis operated was 49 out of 435 (11.2%) interventions. The clinical history was typical in most of the patients and, nevertheless, we noticed a diagnostic delay greater than 24 hours in 31 (63.2%), and greater than 48 hours in 17 patients (34.6%). We verified the existence of a high percentage of perforated appendicitis (36.7%) closely related to a long evolution time, not being able to show, in the group studied, an increase of early appendix perforations in comparison with the rest. These results suggest that the high morbidity of acute appendicitis in old patients is due, to a great extent, to a delay in the performance of the appendectomy.

microRNA profiling in duodenal ulcer disease caused by Helicobacter pylori infection in a Western population.

Although the connection of microRNAs (miRNAs) to some diseases is well established, their involvement in chronic infections such as Helicobacter pylori has received less attention. The aim was to compare miRNA expression profiling in patients with duodenal ulcer (DU) due to H. pylori infection with that in infected patients without DU and in uninfected patients. The miRNA expression profile was determined by microarrays in antral mucosal samples from well-characterized dyspeptic patients (n = 46). The most significant set of miRNAs was subsequently analysed in an independent validation group of patients (n = 42). Transcripts for IL8, IL12p40, IL12p35 and IL23p19, the signalling molecules MYD88, GATA6, SOCS2 and STAT6 and H. pylori virulence factors cagA and VacA were analysed. Microarray experiments showed that 17 miRNAs were deregulated in the mucosa of H. pylori-infected patients. No significant differences were observed between normal and DU patients. PCR confirmed the up-regulation of miR-9, miR-146a, miR-155 and miR-650 and the down-regulation of miR-96 and miR-204 in the independent validation set of patients. Importantly, miR-9, miR-96, miR-146a and miR-650 expression was specific to chronic-active gastritis. H. pylori-infected patients showed higher levels of IL8 and IL12p40 mRNAs and lower levels of GATA6 and SOCS2 mRNAs. The antral mucosa of patients with non-active or chronic-active gastritis showed significantly lower levels of GATA6, MYD88, SOCS2 and STAT6 mRNAs compared with patients without gastritis. The down-regulation of these factors was not correlated with the expression of any of the validated miRNAs. The exact role of the miRNA changes observed will require further study.

Carbon monoxide and methanol oxidation at platinum catalysts supported on ordered mesoporous carbon: the influence of functionalization of the support.

The influence of different functionalization treatments of the support on the electrocatalytic activity towards CO and methanol oxidation at platinum nanoparticles deposited on ordered mesoporous carbons (OMC) has been studied for the first time. Before deposition of the metal, the carbon support was functionalized applying several procedures, with the purpose to generate oxygenated groups for anchoring the Pt nanoparticles by the formic acid (FM) and borohydride (BM) reduction methods. Good dispersion of the catalyst was obtained in all cases. It has been shown that particle size, and consequently the lattice parameter and metal surface area, depends on the functionalization treatment employed. CO and methanol electrooxidation was studied at all prepared catalysts applying cyclic voltammetry. It was observed that CO stripping occurs at more negative potentials (around 0.10-0.15 V) with these supports with respect to Vulcan XC-72 supported catalysts, and the best results for both methods were achieved with OMC functionalized with concentrated nitric acid for 0.5 h. This carbon support presents a higher amount of oxygenated groups without the loss of the ordered structure. In situ infrared studies have been performed for the first time with this type of catalyst, showing that the effect of the carbon support on the CO oxidation potential is similar to the presence of a second metal as Ru under the same experimental conditions. Methanol electrooxidation is also dependent on the nature of the support, as proved from both cyclic voltammetry and chronoamperometry. In this case, results depend on the method of nanoparticles preparation and seem to be better for BM.

[Cytoarchitectural structure of the areas of language]. / Estructura citoarquitectónica de las areas del lenguaje.

INTRODUCTION AND DEVELOPMENT: There is a correlation between the higher brain functions and the degree of development of the associated cortices, but their efficiency depends on the patterns of cytoarchitectural organisation. Specialised areas can be distinguished in the neocortex and in the thalamus. Portions of the pars opercularis and triangularis of the inferior frontal gyrus (Broca's area) together with the posterior temporal region (Wernicke's area) are essential for the production and understanding of human speech, these being more developed in the left hemisphere of humans. The frontal lobe in front of Brodmann's areas numbers 6 and 8 represents a late phylogenetic acquisition, which is only developed in primates and in humans, that acts to sustain highly discriminating activities linked to the planning, execution and control of tasks that require the selection of programmes and flexibility for them to be applied. In its anterolateral sector, the temporal lobe has areas that are only shared with primates (such as area 20) or which are exclusive to humans (area 38), and which are important when it comes to assessing the vital significance of intellectually captured events. CONCLUSIONS: The three fundamental features of the human cerebral cortex are considerable folding, stratification and pillarisation, and its scant thickness. The rationale behind this work was to present the complex and sophisticated biological substrate for the development of speech and language in human beings and the connections within the temporal lobe and outside them, as well as the bi-hemispheric competence needed to enable the higher tutoring processes.

Identification of organically associated trace elements in wood and coal by inductively coupled plasma mass spectrometry.

1-Methyl-2-pyrrolidinone (NMP) was used to extract samples of wood (forest residue) and coal; the extracts were analysed by inductively coupled plasma mass spectrometry (ICP-MS) using two different sample preparation methods, in order to identify trace elements associated with the organic part of the samples. A sample of fly ash was similarly extracted and analysed in order to assess the behaviour of the mineral matter contained within the wood and coal samples. 32% of the biomass was extracted at the higher temperature and 12% at room temperature while only 12% of the coal was extracted at the higher temperature and 3% at room temperature. Less than 2% of the ash dissolved at the higher temperature. Size exclusion chromatograms of the extracts indicated the presence of significant amounts of large molecular mass materials (>1000 mu) in the biomass and coal extracts but not in the ash extract. Trace element analyses were carried out using ICP-MS on the acid digests prepared by 'wet ashing' and microwave extraction. Sixteen elements (As, Ba, Be, Cd, Co, Cr, Cu, Ga, Mn, Mo, Ni, Pb, Sb, Se, V and Zn) were quantified, in the samples before extraction, in the extracts and in the residues. Concentrations of trace elements in the original biomass sample were lower than in the coal sample while the concentrations in the ash sample were the highest. The major trace elements in the NMP extracts were Ba, Cu, Mn and Zn from the forest residue; Ba, Cu, Mn, Pb and Zn from the coal; Cu and Zn from the ash. These elements are believed to be associated with the organic extracts from the forest residue and coal, and also from the ash. Be and Sb were not quantified in the extracts because they were present at too low concentrations; up to 40% of Mn was extracted from the biomass sample at 202 degrees C, while Se was totally extracted from the ash sample. For the forest residue, approximately 7% (at room temperature) and 45% (at 202 degrees C) of the total trace elements studied were in the extract; for the coal, approximately 8% (at room temperature) and 23% (at 202 degrees C) were in the extract. For the ash, only 1.4% of the trace elements were extracted at 202 degrees C, comprising 25% of Cd but less than 1% of Pb.

Effect of intravenous glucagon and glucagon-(1-21)-peptide on motor activity of sphincter of Oddi in humans.

Glucagon-(1-21)-peptide, the peptide containing the amino acid sequence (1-21) of glucagon, has the same spasmolytic effect as the complete molecule, without its metabolic action. The effect of glucagon and glucagon-(1-21)-peptide on sphincter of Oddi motor activity was evaluated in 20 patients undergoing ERCP and endoscopic biliary manometry. Glucagon produced a nonsignificant decrease in basal pressure, but significantly reduced both frequency and amplitude of phasic activity of the sphincter of Oddi. Glucagon-(1-21)-peptide showed no effect on basal pressure and amplitude of phasic activity, but provoked a significant reduction of frequency of phasic contraction.