Attentional network task performance in schizophrenic patients.

Several studies have researched the attentional functioning of schizophrenic patients by means of the Attentional Network Test. The present work reviews these studies and assesses the clinical relevance of their results. Both the reviewed data and our own results suggest that the Attentional Network Test does not provide a clear-cut discrimination of the attentional profile of schizophrenic patients from a clinical point of view. However, after classifying patients according to their psychotic symptoms, it became evident that positive syndrome patients are less efficient at tasks that tap the orientation network.

Full Transcriptomic Response of Pseudomonas aeruginosa to an Inulin-Derived Fructooligosaccharide.

Pseudomonas aeruginosa is an ubiquitous gram-negative opportunistic human pathogen which is not considered part of the human commensal gut microbiota. However, depletion of the intestinal microbiota (Dysbiosis) following antibiotic treatment facilitates the colonization of the intestinal tract by Multidrug-Resistant P. aeruginosa. One possible strategy is based on the use of functional foods with prebiotic activity. The bifidogenic effect of the prebiotic inulin and its hydrolyzed form (fructooligosaccharide: FOS) is well established since they promote the growth of specific beneficial (probiotic) gut bacteria such as bifidobacteria. Previous studies of the opportunistic nosocomial pathogen Pseudomonas aeruginosa PAO1 have shown that inulin and to a greater extent FOS reduce growth and biofilm formation, which was found to be due to a decrease in motility and exotoxin secretion. However, the transcriptional basis for these phenotypic alterations remains unclear. To address this question we conducted RNA-sequence analysis. Changes in the transcript level induced by inulin and FOS were similar, but a set of transcript levels were increased in response to inulin and reduced in the presence of FOS. In the presence of inulin or FOS, 260 and 217 transcript levels, respectively, were altered compared to the control to which no polysaccharide was added. Importantly, changes in transcript levels of 57 and 83 genes were found to be specific for either inulin or FOS, respectively, indicating that both compounds trigger different changes. Gene pathway analyses of differentially expressed genes (DEG) revealed a specific FOS-mediated reduction in transcript levels of genes that participate in several canonical pathways involved in metabolism and growth, motility, biofilm formation, ß-lactamase resistance, and in the modulation of type III and VI secretion systems; results that have been partially verified by real time quantitative PCR measurements. Moreover, we have identified a genomic island formed by a cluster of 15 genes, encoding uncharacterized proteins, which were repressed in the presence of FOS. The analysis of isogenic mutants has shown that genes of this genomic island encode proteins involved in growth, biofilm formation and motility. These results indicate that FOS selectively modulates bacterial pathogenicity by interfering with different signaling pathways.

Cloning and expression of an endo-1,4-ß-xylanase from the coffee berry borer, Hypothenemus hampei.

BACKGROUND: The coffee berry borer, Hypothenemus hampei, reproduces and feeds exclusively on the mature endosperm of the coffee seed, which has a cell wall composed mainly of a heterogeneous mixture of hemicellulose polysaccharides, including arabinoxylans. Xylanases are digestive enzymes responsible for the degradation of xylan based polymers, hydrolyzing them into smaller molecules that are easier to assimilate by insects. We report the cloning, expression and enzymatic characterization of a xylanase gene that was identified in the digestive tract of the coffee berry borer. METHODS: The complete DNA sequence encoding a H. hampei xylanase (HhXyl) was obtained using a genome walking technique in a cDNA library derived from the borer digestive tract. The XIP-I gene was amplified from wheat (Triticum aestivum variety Soisson). A Pichia pastoris expression system was used to express the recombinant form of these enzymes. The xylanase activity and XIP-I inhibitory activity was quantified by the 3,5-dinitrosalicylic (DNS). The biological effects of XIP-I on borer individuals were evaluated by providing an artificial diet enriched with the recombinant XIP-I protein to the insects. RESULTS: The borer xylanase sequence contains a 951 bp open reading frame that is predicted to encode a 317-amino acid protein, with an estimated molecular weight of 34.92 kDa and a pI of 4.84. Bioinformatic analysis revealed that HhXyl exhibits high sequence homology with endo-ß-D-xylanases of Streptomyces bingchenggensis from glycosyl hydrolase 10 (GH10). The recombinant xylanase showed maximal activity at pH 5.5 and 37°C. XIP-I expressed as a recombinant protein inhibited HhXyl activity in vitro and caused individual H. hampei mortality in bioassays when included as a supplement in artificial diets. CONCLUSION: A xylanase from the digestive tract of the coffee berry borer was identified and functionally characterized. A xylanase inhibitor protein, XIP-I, from wheat was shown to be a potent inhibitor of this xylanase, suggesting that its deployment has potential as a strategy to control coffee berry borer colonization of coffee plants.

ESPECIES DE DRYOPHTHORINAE (COLEOPTERA: CURCULIONIDAE) ASOCIADAS A PLÁTANO Y BANANO (Musaspp.) EN COLOMBIA / Dryophthorinae Species (Coleoptera: Curculionidae) Associted to Platain and Banana crops (Musaspp.) in Colombia

Se presenta una sinopsis de los escarabajos de la subfamilia Dryophthorinae (Coleoptera: Curculionidae) asociados a cultivos de plátano y banano en Colombia. Adicionalmente se ofrecen claves ilustradas para las especies del país. Se registran seis especies asociadas a dichos cultivos: Cosmopolites sordidus (Germar, 1824), Metamasius hemipterus (Linnaeus, 1758), Metamasius hebetatus (Gyllenhal, 1838), Metamasius submaculatus Champion, 1910, Rhyncophorus palmarum (Linnaeus, 1758) y Polytus mellerborgii (Boheman, 1838).

This synopsis is about beetle&#’;s subfamily Dryophthorinae (Coleoptera: Curculionidae) associated to plantain and banana crops. Additionally keys illustrated for the species of the country are offered. Six species associated to these cultures are registered: Cosmopolites sordidus (Germar, 1824), Metamasius hemipterus (Linnaeus, 1758), Metamasius hebetatus (Gyllenhal, 1838), Metamasius submaculatus Champion, 1910, Rhyncophorus palmarum (Linnaeus, 1758) y Polytus mellerborgii (Boheman, 1838).