Induced expression of the Candida albicans multidrug resistance gene CDR1 in response to fluconazole and other antifungals

The Candida albicans CDR1 gene encodes a member of the ABC-type family of multidrug transporters which has been shown to be involved in azole resistance. Using an in-frame gene fusion between the CDR1 open reading frame and the green fluorescent protein allele yEGFP3, an optimized derivative for its use in C. albicans, we show here how the CDR1-yEGFP3 gene expression is induced in response to azoles as well as to other structurally unrelated drugs like cycloheximide. Moderate increases were observed for calcofluor, canavanine, 5′-fluorcytosine, cilofungin and caffeine, while no induction was found for the antifungals benomyl and amphotericin B or hydrogen peroxide at subinhibitory concentrations. The use of confocal microscopy enabled us to localize the Cdr1p fusion protein at the cell periphery, thus suggesting a cytoplasmic membrane localization. These results suggest deregulation of CDR1 gene as a putative mechanism for the generation of azole resistance in this clinically important pathogenic fungus. © 1998 John Wiley & Sons, Ltd.     

An Experimental Study of a Pilot Plant Deasphalting Process in Subcritical and Supercritical Conditions

The authors aimed to study the deasphalting process on laboratory scale through the design and development of a supercritical extraction experimental unit. Extractions in subcritical and supercritical conditions were carried out using petroleum residue as feedstock and propane as solvent. Temperature and pressure were manipulated in order to maintain the solvent in the required conditions, thus facilitating the extraction process and avoiding sharp changes in the system. In supercritical conditions, the products in the deasphalted oil stream present adequate characteristics for the production of lubricant oils and those in the asphalt residue stream present an elevated concentration of asphalt molecules.     

Deasphalting process using supercritical water

The authors aimed to study the deasphalting process on laboratory scale through the design and development of a supercritical extraction experimental unit. The experimental unity used in tests is composed by a pump, an extractor with useful volume of 3 L and one separator vessel. Extractions in supercritical condition were carried out using petroleum residue (vacuum residuum) as feedstock and water as solvent. Temperature and pressure were manipulated to maintain the solvent in the required conditions, thus facilitating the extraction process and avoiding sharp changes in the system. In both phases, the products in the deasphalted oil stream present adequate characteristics for the production of lubricant oils and those in the asphalt residue stream present an elevated concentration of asphalt molecules.     

Microstructural changes induced in Portland cement-based materials due to natural and supercritical carbonation

Supercritical carbonation of Portland cement binders was studied to analyse the influence of the type of cement on carbonation at high CO₂ pressures (CO₂ at 20 MPa and 318 K) and to improve the understanding of the effects on the microstructure and physicochemical properties of binders. The results were compared with those obtained in a natural exposure. Microstructural properties of supercritically and atmospherically carbonated Portland cement binders were examined using the complementary analytical techniques of FTIR, TG-DTA, and BSEM-EDX. Supercritically carbonated binders showed a microstructure based on a more polymerized and lower Ca form of CSH gel, formed by decalcification of high-Ca form of CSH gel. Results suggested that during the treatment at artificially intensified conditions, the crystallized calcium carbonate came mainly from the carbonation of the CSH gel, and at atmospheric conditions, from the carbonation of the portlandite phase.     

Serological proteome analysis to identify systemic candidiasis patients in the intensive care unit: Analytical, diagnostic and prognostic validation of anti-Candida enolase antibodies on quantitative clinical platforms

Systemic candidiasis (SC) is associated with high morbidity and mortality, because it generally affects patients with severe underlying diseases and its diagnosis is difficult and often delayed, resulting in delayed therapy. We used serological proteome analysis to screen serum anti‐Candida IgG antibody‐reactivity profiles in 24 patients under intensive care, 12 of which had confirmed SC (fungal cultures), and in 12 healthy subjects. A total of 15 immunogenic proteins from Candida albicans protoplast lysates were differentially immunorecognized by serum IgG antibodies from SC patients compared to controls. Two‐way hierarchical clustering and principal‐component analyses of these antibody‐reactivity patterns accurately differentiated SC patients from controls. Anti‐Eno1p IgG antibodies were found to be present at high abundance in SC patients and be an important molecular fingerprint in serum for SC diagnosis. Differential anti‐Eno1p IgG antibody reactivity was further validated by a tag capture ELISA and a Western blot assay in 45 SC patients and 118 non‐SC subjects. Both quantitative assays provided comparable analytical, diagnostic and prognostic performances, and verified initial proteomic‐profiling results. If confirmed in prospective cohort studies, these anti‐Eno1p IgG antibodies might be useful for SC diagnosis. However, these, at least as measured by these clinical platforms, appear to have limited prognostic value in SC patients.     

Functional response of diluted dough matrixes in high-fibre systems: A viscometric and rheological approach

Hydrocolloids (carboxymethylcellulose, locust bean gum, high ester pectin) and prebiotic oligosaccharides (inuline and gluco-oligosaccharides), singly and in hydrocolloid/oligosaccharide binary blends were tested at different level of fibre replacement (from 0% up to 12%) to investigate the impact of dietary fibres on bread dough linear and non linear rheological performance. Incorporation of locust bean and carboxymethylcellulose at a replacement higher than 6% into bread doughs led highly reinforced hydrated flour-fibre blends with promoted values for storage and loss moduli, hardness, and pasting/gelling features; whereas pectin and pectin blends systems at any substitution level were the softer and stickier. Obtained results on rheological performance strongly endorse the viability of locust bean and carboxymethylcellulose blended with prebiotic oligosaccharides, to replace wheat flour at medium-high substitution level to serve either as sources of dietary fibre for the production of healthy baked goods or as thickening and structuring agents for baking industry.     

Multidimensional statistical analysis of the parameterization of a genetic algorithm for the optimal ordering of tables

The optimal table row and column ordering can reveal useful patterns to improve reading and interpretation. Recently, genetic algorithms using standard crossover and mutation operators have been proposed to tackle this problem. In this paper, we carry out an experimental study that adds to this genetic algorithm crossover and mutation operators specially designed to deal with permutations and includes other parameters (initialization, replacement policy, mutation and crossover rates and stopping criteria) not examined in previous works. A proper analysis of the results must take into account all the parameters simultaneously, since the wrong conclusions can be drawn by studying each separately from the others. This is why we propose a framework for a multidimensional analysis of the results. This includes multiple hypothesis testing and a regression tree that builds a parsimonious and predictive model of the suitable configurations of the parameters.     

Flow patterns in conical and cylindrical hydrocyclones

Using a two beam, 300 mW laser Doppler velocimeter, the tangential and axial velocity fields were determined for the water flow in a 102-mm modular hydrocyclone. The body of the equipment could be changed to transform it into a conical or a flat bottom hydrocyclone. During the tests the pressure drop and the diameter of apex and vortex were varied and the axial and the tangential velocities and their turbulence intensity were measured. The results shows that the inlet pressure affects only the magnitude of the velocities, but does not change the flow pattern. The tangential velocity is similar in both types of hydrocylones while the axial velocity is different. In both hydrocyclones the axial velocity is a function of the radial position but, while it is a linear function of the vertical coordinate in the cylindrical hydrocyclone, this is not the case for the conical vessel.     

Cluster methods for assessing research performance: exploring Spanish computer science

The objective of this paper is to propose a cluster analysis methodology for measuring the performance of research activities in terms of productivity, visibility, quality, prestige and international collaboration. The proposed methodology is based on bibliometric techniques and permits a robust multi-dimensional cluster analysis at different levels. The main goal is to form different clusters, maximizing within-cluster homogeneity and between-cluster heterogeneity. The cluster analysis methodology has been applied to the Spanish public universities and their academic staff in the computer science area. Results show that Spanish public universities fall into four different clusters, whereas academic staff belong into six different clusters. Each cluster is interpreted as providing a characterization of research activity by universities and academic staff, identifying both their strengths and weaknesses. The resulting clusters could have potential implications on research policy, proposing collaborations and alliances among universities, supporting institutions in the processes of strategic planning, and verifying the effectiveness of research policies, among others.     

Impact of the addition of resistant starch from modified pea starch on dough and bread performance

The interest in the use of resistant starch (RS) for the development of new bakery products has significantly increased due to its ascribed physiological effects with proven health benefits. The objective of the present work was to analyse the effects of the wheat flour substitution by modified pea starch with high level of RS (PeaP) on breadmaking performance. The effects of PeaP on wheat dough functionality were evaluated by mixing/overmixing properties, texture profile analysis, viscometric profile and thermal properties. Bread quality was evaluated by physico-chemical parameters, crumb texture profile, digital image analysis, nutritional parameters and sensory evaluation. Flour substitution by PeaP up to 20% allowed keeping mechanical, extensional and viscometric parameters without significant hindering of dough machinability. Overdose of modified pea starch (30%) negatively affects dough mixing and overmixing behaviour. As a functional/prebiotic fibre, PeaP addition up to 10–20% of flour replacement entitles the formulation of wheat bread allowing a significant increase in the RS level (from 0.70 to 5.10%), delay/decrease in amylopectin retrogradation, with acceptable changes in bread quality up to 10–20% of flour replacement.