Applicability of lignins from different sources as antioxidants based on the protective effects on lipid peroxidation induced by oxygen radicals

Increasing evidence suggest that excessive concentrations of reactive oxygen species in the human body are involved in a number of pathological events and that oxidative damage to cell components may play an important pathophysiological role in many types of human diseases. Several studies have shown the possible benefits of antioxidants from plant sources in altering, reversing or forestalling the negative effects of oxidative stress.The study was designed to evaluate whether lignins prevent H₂O₂-induced lipid peroxidation. The protective effect of industrial lignins obtained from different sources against hydrogen peroxide induced oxidation was investigated in normal human red blood cells (RBCs). RBCs, preincubated with different amounts of lignins and challenged with hydrogen peroxide were analyzed for lipid peroxidation. The high molecular weight can be considered as one of the main factors decreasing the radical scavenging activity. When comparing different lignins the inhibitory effects against lipid peroxidation were notably related to their molecular weights. In this sense bagasse with the lowest Mn was the greatest antioxidant and lignosulfonate with the highest Mn was the lowest antioxidant lignin.These results open the possibility of new applications of lignins. The potential health benefits and industrial applications of lignins make them a promising research resource.     

Applied information retrieval and multidisciplinary research: new mechanistic hypotheses in Complex Regional Pain Syndrome

Background

Collaborative efforts of physicians and basic scientists are often necessary in the investigation of complex disorders. Difficulties can arise, however, when large amounts of information need to reviewed. Advanced information retrieval can be beneficial in combining and reviewing data obtained from the various scientific fields. In this paper, a team of investigators with varying backgrounds has applied advanced information retrieval methods, in the form of text mining and entity relationship tools, to review the current literature, with the intention to generate new insights into the molecular mechanisms underlying a complex disorder. As an example of such a disorder the Complex Regional Pain Syndrome (CRPS) was chosen. CRPS is a painful and debilitating syndrome with a complex etiology that is still unraveled for a considerable part, resulting in suboptimal diagnosis and treatment.

Results

A text mining based approach combined with a simple network analysis identified Nuclear Factor kappa B (NFκB) as a possible central mediator in both the initiation and progression of CRPS.

Conclusion

The result shows the added value of a multidisciplinary approach combined with information retrieval in hypothesis discovery in biomedical research. The new hypothesis, which was derived in silico, provides a framework for further mechanistic studies into the underlying molecular mechanisms of CRPS and requires evaluation in clinical and epidemiological studies.

     

Genetic identification of squids (families Ommastrephidae and Loliginidae) by PCR-RFLP and FINS methodologies

Cephalopods are a taxonomic group that contains a great number of families, genera and species, with many of them very important at the commercial level. The existence of very similar species in this class added up to the transformation process applied to them makes it difficult or even impossible for species identification based on morphological characterization. Moreover, the global commerce makes it possible that one determined species can be marketed in its antipodes. These questions suggest the necessity of molecular techniques to solve this situation. In the present work, a genetic method was developed on the basis of the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and forensically informative nucleotide sequencing (FINS) technique and makes possible the identification of more than 20 species belonging to the families Ommastrephidae and Loliginidae, as well as some octopus and sepia species. The PCR was employed to amplify 651 and 208 bp fragments of the mitochondrial cytochrome b gene. These molecular systems were applied to fresh, frozen, precooked, even canned cephalopods, allowing for the identification of the species included in these products. Therefore, these molecular tools could be applied in questions related to correct labeling, traceability, and importation controls of squids, sepias, and octopuses.     

Rapid identification of seaweeds in food products by PCR combined with ALF-RFLP and FINS methodologies

In the present study, two methods for the genetic identification of the most important seaweed species used for human consumption were developed. Both are carried out through PCR amplification of an 18S rRNA gene fragment. The first one is based on the phylogenetic analysis of DNA sequences (FINS), while the second is based on length polymorphism and RFLP visualized by means of an ALF system. The main novelty of this work lies in the fact that it allows genetic identification of the main commercial species of seaweed. Moreover, the developed systems can be applied to all kinds of processed products, including those that have undergone intensive transformation, as for instance canned foods. These methodologies also permit the detection of species in complex matrixes where more than one algal species is present. The methods were validated using products manufactured in a pilot plant showing correct functioning. Finally, the methods were applied to 23 commercial samples including some that had been subjected to intensive thermal treatment, allowing the detection of those that were incorrectly labeled (30%). Therefore, these molecular tools can be used for clarifying questions related to the correct labeling and traceability of commercial products that include some seaweeds in their composition.     

Development of a genetic manipulation system for Haemophilus parasuis

Haemophilus parasuis is a member of the family Pasteurellaceae and an important respiratory-tract pathogen of swine, which is the etiological agent of Glasser's disease. Because no genetic manipulation system is available for H. parasuis so far, in vivo studies about the role of its genes involved in virulence are unfeasible. Here we demonstrate that H. parasuis has a cyclic AMP (cAMP)-dependent natural transformation system that enables the uptake of DNA in which the ACCGAACTC sequence signal must be present. After improving DNA transformation parameters, such as cAMP and DNA concentration and exposition time of the exogenous DNA, a knockout mutant of H. parasuis defective in the thy gene, encoding the thymidylate synthase enzyme, has been constructed. Data presented in this work open the possibility for the functional analysis of genes involved in the infectious process of this animal pathogen.     

Characterization of platelet and soluble-porcine P-selectin (CD62P)

P-selectin (CD62P), an adhesion molecule expressed on activated endothelial cells and platelets, mediates the initial attachment of leukocytes to the stimulated endothelium upon inflammation and the interaction between leukocytes and platelets. A soluble form of P-selectin is present in the serum of healthy individuals as a circulating protein and high levels have been described in various pathological situations. The aim of this study was to characterize P-selectin on porcine platelets and investigate the soluble form of this protein, which are uncharacterized in several animal species including pigs. A new monoclonal antibody (mAb) (SwPsel.1.9) against porcine P-selectin was produced using a mouse cell line transfected with pig P-selectin cDNA. This mAb together with a previously described mAb (P-sel.KO.2.5), produced in our laboratory, was used to develop an ELISA to quantify porcine P-selectin. No significant levels of soluble-porcine P-selectin were observed in healthy animals. However, the total amount of P-selectin measured in porcine platelets was similar to that found in humans. Increased levels of this circulating protein were detected in the plasma from pigs after allograft implantation. In vitro, P-selectin expression on platelet membrane was rapidly induced by PMA and thrombin, as assessed by flow cytometry. However, these activators did not stimulate the release of soluble P-selectin. Analysis of the proteolytic cleavage of this protein from COS-transfected cells revealed that PMA treatment failed to cause the shedding of membrane-bound P-selectin. These data suggest that porcine P-selectin is a suitable marker for inflammation and that the mechanism involved in the generation of circulating P-selectin is not proteolytic release.     

Effect of pooling udder skin wipes on the detection of influenza A virus in preweaning pigs

Influenza A virus (IAV) active surveillance in pigs prior to weaning is commonly conducted by collecting individual samples, mostly nasal swabs. Recently, the use of udder skin wipes collected from lactating sows was identified as an effective sampling method to indicate IAV status of suckling piglets prior to weaning. However, there is limited information on the effect of pooling multiple udder wipes on the ability to detect IAV. We evaluated the effect of pooling 3, 5, or 10 udder wipes on the sensitivity of detecting IAV and compared the results with testing the wipes individually. The likelihood of detecting positive udder wipes decreased with pooling when the initial positive cycle threshold value was ≥31.5; pooling of up to 3 samples could be performed without affecting sensitivity significantly. Our results support pooling of udder skin wipes to conduct surveillance of IAV in pigs prior to weaning.     

Effect of paclobutrazol,prohexadione-Ca,deficit irrigation,summer pruning and root pruning on shoot growth,yield, and return bloom,in a ‘Blanquilla’ pear orchard

During the period 2001–2003 the performance of paclobutrazol, prohexadione-Ca, root pruning, summer pruning and deficit irrigation was studied with respect to a control in a Blanquilla pear orchard. Shoot growth, yield, fruit size, and return bloom were all evaluated.     

Analytical method for assessing potential dermal exposure to captan, using whole body dosimetry, in small vegetable production units in Argentina

An analytical method has been developed that can be used to determine the potential dermal exposure (PDE) of workers to the pesticide captan in small-scale horticultural production units. The methodology is based on the whole body dosimetry technique, using a cotton coverall and cotton gloves as sampling media, with protective clothing worn beneath the cotton media to protect the operator. The quantitative determination of captan was done by gas chromatography-electron capture detector (GC-ECD), with the analytical method validated by measuring limits of detection and quantification, linear ranges, sample recovery and precision. Special emphasis is placed on factors that affected the stability of captan during chromatographic determination. The data generated for potential dermal exposure are presented separately for mixing/loading and application activities. These data are compared with values obtained with visible tracers using a similar field technique. Margin of safety (MOS) values are also calculated for the agricultural procedures studied.