Fotoestabilidad de compuestos fenólicos. Evaluación de su potencial capacidad como aditivos antioxidantes. Photostability of phenolic compounds. Assessment of their potential antioxidant activity as additives.

La autooxidación es la forma de deterioro de los productos grasos más importante después de las alteraciones producidas por microorganismos, lo que representa un tema de gran interés económico para las industrias alimenticia y cosmética, ya que da lugar a la aparición de sabores y olores desagradables lo que hace que estos productos sean inaceptables para el consumidor o que reduzcan su vida útil. Dicho proceso se inicia a partir de la reacción de ácidos grasos con oxígeno y puede ser desencadenado por la exposición del producto graso a la luz medioambiental. En estos casos ocurre un proceso de fotooxidación sensibilizada, con la participación de especies reactivas de oxígeno (ROS). Por esta razón, la preservación de producto graso al efecto de las ROS es un punto de capital importancia. Las industrias intentan evitar la oxidación de los productos grasos mediante diferentes técnicas, como el envasado al vacío o en recipientes opacos, pero también utilizando antioxidantes agregados ex-profeso. En particular, los fenoles son secuestradores no enzimáticos de ROS y radicales libres. Actúan como antioxidantes secundarios o interruptores de la cadena oxidativa de lípidos, desactivando las especies reactivas en sus etapas iniciales y evitando que el proceso oxidativo continúe. Por tal motivo, para el presente Proyecto hemos escogido, como potenciales antioxidantes, dos fenoles estructuralmente relacionados con el hidroxitirosol-un antioxidante natural del aceite de oliva-. A través de reacciones fotosensibilizadas, mediante un estudio cinético, mecanístico, de relaciones estructura-reactividad y de dilucidación de fotoproductos se intentará obtener la información que satisface los objetivos específicos de este Proyecto, a saber: a) la resistencia de dHT frente a la oxidación fotopromovida, y en particular a los procesos fotosensibilizados; b) la propensión de dHT para generar especies oxidantes ya sea por irradiación directa o por interacciones específicas con estados excitados de otras moléculas; c) la influencia del medio sobre la capacidad antioxidante de dHT; d) el establecimiento de relaciones estructura-reactividad en lo referida a la actividad antioxidante de dHT. Se trabajará con distintos tipos de sensibilizadores como generadores de diferentes ROS. Para establecer y dilucidar los aspectos cinéticos y mecanísticos mencionados es necesario obtenerinformación acerca de las constantes cinéticas de los diferentes procesos involucrados. La estrategia de trabajo consistirá en abordar condiciones experimentales tales que inhiban determinadas reacciones competitivas y permitan el desarrollo de otras. Se espera que el conocimiento que se genere a partir de los resultados del presente Proyecto, constituya un importante aporte para el diseño y desarrollo de nuevos antioxidantes liposolubles que posean exacerbadas sus propiedades como fotoprotectores frente a eventuales oxidaciones a las que pueda estar expuesto un producto graso.

Mortar-Techniken zur Behandlung von Grenzschichtproblemen

Elliptic differential equations, finite element method, mortar element method, streamline diffusion FEM, upwind method, numerical method, error estimate, interpolation operator, grid generation, adaptive refinement

The relation of the concentration of macronutrients in the substrate and in the foliage to cell wall thickness and cellulose concentration in the xylem of slash pine (Pinus elliotti)

Sand culture experiments, using a sub-irrigation technique, were installed in order to find out the effects of the macronutrients N, P, K, Ca, Mg and S on growth, aspect, mineral composition, length of fibers, thickness of cell wall and cellulose concentration in slash pine. The aim was to obtain, under controlled conditions, basic information which could eventually lead to practical means designed to increase the rate of growth and to make of slash pine a richer source of cellulose. Nitrogen, Phosphorus, Potassium Experiment A 3 x 3 x 3 factorial design with two replicates was used. Nitrogen was supplied initially at the levels of 25, 50 and 100 ppm; phosphorus was given at the rates of 5, 10 and 20 ppm; potassium was supplied at the rates of 25, 50 and 100 ppm; six months after the experiment was started the first level for each element was dropped to zero. Others macro and all micronutrients were supplied at uniform rates. Fifteen hours of illumination per day were provided. The experimental technique for growing the slash pine seedlings proved quite satisfactory. Symptoms of deficiency of nitrogen, phosphorus and potassium were observed, described and recorded in photographs and water colors. These informations will help to identify abnormalities which may appear under field conditions. Chemical analysis of the several plant parts, on the other hand, give a valuable means to assess the nutritional status of slash pine, thus confirming when needed, the visual diagnosis. The correctness of manurial pratices, on the other hand, can be judged with the help of the analytical data tabulated. Under the experimental conditions nitrogen caused the highest increases on growth, as measured by increments in height and dry weights, whereas the effects of phosphorus and potassium were less marked. Cellulose concentration was not significantly affected by the treatments used. Higher levels of N seemed to decrease both length of fiber elements and the thickness of cell wall. The effects of P and K were not well defined. Calcium, Magnesium, Sulfur Experiment A 3 x 3 x 3 factorial design with two replicates was used. Calcium was supplied initially at the levels of 12.5, 25 and 50 ppm; magnesium and sulfur were given at the rates of 6, 12.5 and 25 ppm. Other macro and micronutrients were supplied at uniform rates, common to all treatments. Three months after starting the experiment the first level for each element was dropped to zero. Symptoms of deficiency of calcium, magnesium and sulfur were observed, described and recorded as in the case of the previous experiment. Chemical analysis were made, both for mineral content and cellulose concentration. Length of fibers and thickness of cell wall were measured. Both calcium and magnesium increase height, sulfur failing to give significant response. Dry weight was beneficially affected by calcium and sulfur. The levels of calcium, magnesium and sulfur in the needles associated with deficiency and maximum growth are comparable with those found in the literature. Cellulose concentration increased when the level of sulfur in the substrate was raised. The thickness of cell wall was negatively affected by the treatments; no effect was observed with regards to length of fibers.

A simple method to purify biologically and antigenically preserved bloodstream trypomastigotes of Trypanosoma cruzi using Deae-cellulose columns

A method to purify trypanosomastigotes of some strains of Trypanosoma cruzi (Y, CL, FL, F, "Berenice", "Colombiana" and "São Felipe") from mouse blood by using DEAE-cellulose columns was standardized. This procedure is a modification of the Lanham & Godfrey methods and differs in some aspects from others described to purify T. cruzi bloodstream trypomastigotes, mainly by avoidance of prior purifications of parasites. By this method, the broad trypomastigotes were mainly isolated, accounting for higher recoveries obtained with strains having higher percentages of these forms: processing of infected blood from irradiated mice could be advantageous by increasing the recovery of parasites (percentage and/or total number) and elution of more slender trypomastigotes. Trypomastigotes purified by this method presented normal morphology and motility, remained infective to triatomine bugs and mice, showing in the latter prepatent periods and courses parasitemia similar to those of control parasites, and also reproducing the polymorphism pattern of each strain. Their virulence and pathogenicity also remained considerably preserved, the latter property being evaluated by LD 50 tests, mortality rates and mean survival time of inoculated mice. Moreover, these parasites presented positive, clear and peripheral immunofluorescence reaction at titres similar to those of control organisms, thus suggesting important preservation of their surface antigens.

Occurrence and bioaccumulation study of PCDD and PCDF from mineral feed additives

Occurrence of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) was evaluated in sepiolite as a widely employed binder and anti-caking agent for animal feed. Also, naturally contaminated kaolinitic clay was used for comparative purposes. Since sepiolite shows remarkable adsorption properties, particular interest was paid to the extraction steps as they become critical for the final determination of these pollutants in such matrixes. Furthermore, classical Soxhlet extraction using different extracting strategies as well as acid treatment were carried out with simultaneous liquid-liquid extraction. Results obtained depended on the extraction procedure applied. Acid treatment or Soxhlet extraction using a mixture of toluene:ethanol as solvent allowed to reach the minimum requirements of recovery rates. However, Soxhlet extraction using a mixture cyclohexane:toluene as extracting solvent did not allow to comply with minimum specifications for recovery. Significant differences were obtained in TEQ units when acid treatment was applied in comparison to Soxhlet extraction. This fact can be explained because the use of drastic acid conditions allows removing strongly adsorbed analytes which can be uniquely extracted after a total destruction of the crystalline structure of sepiolite. On the contrary, Soxhlet extraction was not able to destroy the structure of sepiolite and as a consequence the PCDDs/Fs were strongly adsorbed in the internal structure of the mineral. From biological point of view the availability of these toxicants constitutes a critical aspect playing an important role in the final decision choosing particular analytical procedures. Then, acid conditions in the digestive tract should be taken into account. In this scenario, a bioaccumulation study was conducted to evaluate the transference of PCDDs/PCDFs from the sepiolite into the animal tissues when fed with feed containing sepiolite. To this end, chickens were used as a model to examine the bioavailability of PCDDs/PCDFs. Four groups of chickens were exposed through their diet to a control feed, feed with 3% w/w sepiolite as additive, feed contaminated with PCDDs/PCDFs at concentration around 2.8 pg WHO-TEQ/g and feed with 2% of a contaminated kaolinitic clay (460 pg TEQ/g mineral). Livers of the four studied groups were analyzed throughout the exposure period. Results of this trial showed that the performance of broilers was not affected by the presence of dioxins at levels tested, and chickens did not show any abnormal behaviour. Dioxins intentionally added to the diet were absorbed and accumulated in the liver in a significant manner, whereas the PCDDs/Fs from sepiolite were not available for chickens since livers from broilers fed 3% sepiolite presented similar WHO-TEQ values than those from broilers fed control diet.

Use of glass beads and CF 11 cellulose for removal of leukocytes from malaria-infected human blood in field settings

Passage of malaria infected blood through a two-layered column composed of acid-washed glass beads and CF 11 cellulose removes white cells from parasitized blood. However, because use of glass beads and CF 11 cellulose requires filtration of infected blood separately through these two resins and the addition of ADP, the procedure is time-consuming and may be inapropriate for use in the field, especially when large numbers of blood samples are to be treated. Our modification of this process yields parasitized cells free of contaminating leukocytes, and because of its operational simplicity, large numbers of blood samples can be processed. Our procedure also compares well with those using expensive commercial Sepacell resins in its ability to separate leukocytes from whole blood. As a test of usefulness in molecular biologic investigations, the parasites obtained from the blood of malaria-infected patients using the modified procedure yield genomic DNA whose single copy gene, the circumsporozite gene, efficiently amplifies by polymerase chain reaction.

Atlas iconographique tomodensitométrique des pathologies bénignes de l'amiante [Computed tomographic atlas of benign asbestos related pathology].

The demonstration by computed tomography of abnormalities related to asbestos is essential for the recognition of industrial disease, the compensation of which has considerable economic consequences. The use of compute tomography, the most reliable technique for the detection of pleuro-parenchymatous abnormalities related to asbestos exposure, has increased considerably in France since the publication of the results of a consensus conference in Paris in 1999. Since that time, developments in technology have noticeably modified the protocols of investigation and increased the sensitivity of the detection of pleural and interstitial parenchymatous abnormalities and of nodules. The technical recommendations and those for the interpretation of pleural and parenchymatous abnormalities need to be well known. They are presented in the form of an atlas that gives detailed criteria for asbestosis, pleural plaques and pleural fibrosis. The diagnosis of pleural plaques depends on the combination of clear limits at the pleural and pulmonary interface, typical topography and multiple, bilateral localization. In the context of asbestos exposure the plaques are characteristic of this exposure, unlike diffuse pleural thickening, crow's feet images, parenchymatous bands and entrapped atalectasis. The writing of the radiological report would be most appropriate on this basis.

Cellulose acetate as solid phase in ELISA for plague

Antigen from Yersinia pestis was adsorbed on cellulose acetate discs (0.5 cm of diameter) which were obtained from dialysis membrane by using a paper punch. ELISA for human plague diagnosis was carried out employing this matrix and was capable to detect amount of 1.3 µg of antigen, 3,200 times diluted positive serum using human anti-IgG conjugate diluted 1:4,000. No relevant antigen lixiviation from the cellulose acetate was observed even after washing the discs 15 times. The discs were impregnated by the coloured products from the ELISA development allowing its use in dot-ELISA. Furthermore, cellulose acetate showed a better performance than the conventional PVC plates.

Kyste synovial de l'épaule traité par aspiration et infiltration sous échographie : rapport de 3 cas avec pathologies différentes

Introduction: Les kystes synoviaux localisés à l'épaule sont des conditions rares résultant de tendinopathies rompues de la coiffe des rotateurs, d'une omarthrose sévère, d'arthropathies microcristallines de l'articulation acromio-claviculaire ou gléno-humérale, ou d'une atteinte secondaire à un rhumatisme inflammatoire chronique. Ils se présentent cliniquement le plus souvent sous la forme d'une tuméfaction fluctuante indolore en regard du moignon de l'épaule ou de l'articulation acromio-claviculaire. L'imagerie par échographie permet de caractériser aisément la présence de ces kystes. La prise en charge thérapeutique est généralement non invasive par aspiration-infiltration. Les cas réfractaires sont susceptibles de subir une intervention chirurgicale en fonction de l'âge et de l'état général du patient.Patients et Méthodes: Nous rapportons les cas de 3 patients avec imagerie par échographie et IRM ou Scanner. Le premier cas est celui d'un homme de 47 ans, greffé rénal, présentant une arthrite récidivante des épaules sur arthropathie microcristalline mixte. De multiples kystes synoviaux sont mis en évidence dans la musculature du supra-épineux gauche, communiquant avec l'articulation acromio-claviculaire. Le patient a bénéficié à plusieurs ponctions-infiltrations dirigées par ultrasonographie. Le deuxième cas est celui d'un patient de 32 ans connu pour une arthrite psoriasique évoluant depuis 6 ans. Il présente une importante tuméfaction en regard du biceps à gauche sur un kyste synovial provenant de l'articulation gléno-humérale. Il bénéficie également d'une ponction-infiltration dirigée par ultrason. Le troisième cas est celui d'une femme de 91 ans chez qui au status d'entrée on objective une volumineuse masse polylobée en regard de l'acromio-claviculaire, présente depuis 2002 qui n'a jamais été symptomatique. Un US, puis un CT montrent qu'il s'agit de volumineux kystes articulaires en relation avec une arthropathie sévère dégénérative et à apatite de l'acromio-claviculaire.Résultats: Les trois patients ont bénéficié d'une imagerie diagnostique par échographie complétée par une IRM ou Scanner. Tous les trois ont également subi une aspiration dirigée sous échographie. Dans le premier cas, deux aspiration-infiltration des kystes qui apportaient une évolution favorable avec diminution important des kystes. Dans le deuxième cas nous avons retrouvé un kyste après 2 aspirations et dans ce cas une intervention chirurgicale est considérée. Dans le troisième cas, asymptomatique, une résection à visée esthétique a été refusée par la patiente.Conclusion: Les kystes synoviaux localisés à l'épaule restent des conditions rares, provenant d'entités diverses. Nous rapportons le développement de kystes synoviaux de l'épaule dans une arthropathie microcristalline chez un patient greffé rénal, dans une arthrite psoriasique chez un jeune patient en poussée inflammatoire, et finalement de gros kystes asymptomatiques chroniques sur une atteinte dégénérative et microcristalline chez une patiente âgée. Le diagnostic de ces kystes peut être rapidement obtenu par échographie, permettant l'aspiration guidée avec analyse du liquide. En raison d'un fort taux de récidive malgré un traitement par aspiration-infiltration, une intervention chirurgicale de ces kystes est considérée.

Additives and Protein-DNA Combinations Modulate the Humoral Immune Response Elicited by a Hepatitis C Virus Core-encoding Plasmid in Mice

Humoral and cellular immune responses are currently induced against hepatitis C virus (HCV) core following vaccination with core-encoding plasmids. However, the anti-core antibody response is frequently weak or transient. In this paper, we evaluated the effect of different additives and DNA-protein combinations on the anti-core antibody response. BALB/c mice were intramuscularly injected with an expression plasmid (pIDKCo), encoding a C-terminal truncated variant of the HCV core protein, alone or combined with CaCl2, PEG 6000, Freund's adjuvant, sonicated calf thymus DNA and a recombinant core protein (Co.120). Mixture of pIDKCo with PEG 6000 and Freund's adjuvant accelerated the development of the anti-core Ab response. Combination with PEG 6000 also induced a bias to IgG2a subclass predominance among anti-core antibodies. The kinetics, IgG2a/IgG1 ratio and epitope specificity of the anti-core antibody response elicited by Co.120 alone or combined with pIDKCo was different regarding that induced by the pIDKCo alone. Our data indicate that the antibody response induced following DNA immunization can be modified by formulation strategies.

Pathologies mimicking deep venous thrombosis of the legs: pictorial review of US findings : P27

Purpose: Precise diagnosis of DVT of the legs is a challenging problem, not only in front of suspicion of PE, but also in all status of leg pain, warmth and swelling. Clinical diagnosis has a low accuracy and further investigations are mandatory in order to diagnose DVT. Amongst the possible investigations, US has a high specificity and a good NPV. However, many pathologies unrelated to the veins may mimic the signs and symptoms of DVT and have to be recognized in order to make the correct diagnosis. The purpose of this paper is to review the results of the US investigations of the legs performed in our Department during the last three years for a suspicion of DVT and describe alternative diagnoses mimicking DVT. Methods and materials: Through a RIS-based search, we retrospectively reviewed all the cases of US of the legs performed in our Department between January 2006 and December 2008 for a suspicion of DVT. We selected the cases of positive findings unrelated to the veins and illustrated these findings with characteristic images. Results: 419 US of the legs were performed between December 2006 and December 2008 for a suspicion of DVT. Among these, 75 were positive for DVT, and 79 for alternative diagnosis. The most common alternative diagnosis was edema of the legs (31%), followed by hematoma (23%). Other findings were Baker cysts (13%), cellulitis (10%) and lymphoceles (5%). Rare diagnoses were arterio-venous malformations, pseudoaneurysms, pelvic masses, necrosing fasciitis, intramuscular abscesses, subcutaneous seromas, sarcoma and ganglion cysts. Conclusion: A greater knowledge of the US appearance of the pathologies mimicking DVT may help to make the correct diagnosis, avoiding further expensive investigations or inappropriate anticoagulant therapy.

Aptitude à la conduite, pathologies psychiatriques et psychotropes chez la personne âgée [Driving ability, mental illness and psychotropic medication in the elderly].

Fitness to drive in elderly drivers is most commonly discussed with a focus on cognitive impairment. Therefore, this article is focussing on mental illness and the use of psychotropic drugs in elderly drivers, which can both interfere with fitness to drive. Based on a detailed literature review and on clinical judgement, we propose signposts and "red flags" to judge the individual risks. Health professionals dealing with elderly patients should in particular be aware of the dangers related to cumulative risks and need to inform the patients appropriately. For medico-legal reasons the information provided to patients must be written down in the medical record. Individual counselling is important as fitness to drive is a complex topic.