Snake Venom Peptides: Promising Molecules with Anti-Tumor Effects

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Colobome maculaire unilatérale: à propos d’un cas

Le colobome maculaire est une affection congénitale en rapport avec une anomalie de fermeture de la fissure foetale, pouvant être intégré dans un cadre héréditaire. Il se caractérise cliniquement par une acuité visuelle basse avec une lésion excavée  maculaire où le tissu rétinien normal est absent ou rudimentaire et la sclère est  ectasique. La tomographie en cohérence optique maculaire est fortement évocatrice du diagnostic et le bilan électrophysiologique s'il est demandé est altéré. Le diagnostic différentiel se pose avec les pathologies entrainant une lésion atrophique et excavée de la macula, particulièrement la toxoplasmose congénitale

Préparation du jben pasteurisé à l'aide de levains lactiques sélectionnés

Dans le but d'améliorer la qualité du fromage frais traditionnel (jben), des essais de préparation de ce produit à partir du lait pasteurisé inoculé avec des levains lactiques sélectionnés ont été effectués. La procédure de préparation est basée sur l'inoculation de levain au lait pasteurisé à raison de 3%, l'addition de la présure après maturation du lait (20 à 25' Dornic), le moulage du caillé à pH 4,4 - 4,6, le démoulage du fromage à extrait sec de 22 à 30% et enfin une étape de séchage de 24h à température ambiante. Pour lejben salé, le sel (1,5%) a été ajouté par saupoudrage après démoulage. L'adoption d'une procédure standardisée de préparation du jben a donné lieu à des produits dont la composition physico-chimique est relativement régulière. L'utilisation de lait pasteurisé et le respect des règles de l'hygiène durant la préparation ont permis l'obtention de produits de bonne qualité bactériologique (peu ou pas de coliformes, absence de germes pathogènes). L'analyse sensorielle du fromage frais a montré que les produits préparés à l'aide du levain constitué de Lactococcus lactis subsp. lactis, L. lactis subsp.lactis var.diacetylactis et Lactobacillus casei subsp. casei étaient les mieux appreciés par rapport aux échantillons préparés avec d'autres levains et à ceux du commerce.Manufacture of pasteurizedjben using selected lac tic startersTo improve the quality ofthe Jben (a tradition al Moroccan fresh cheese), preparation trials ofthis product from pasteurized milk using selected lactic starters were conducted. The procedure of cheesemaking adopted includes inoculation ofpasteurized milk with 3% starter culture, addition ofrennet after milk maturation (0.20 to 0.25% lactic acid), curd moulding at pH of 4.4 - 4.6, unmoulding when the dry matter reached 22 to 30%, and drying storage of 24h at ambient temperature. In salted jben, salt (1,5%) was added immediately after unmoulding. Standardization ofthe processing led to products with relatively regular chemical composition. These products made from pasteurized milk with hygienic manufacturing practice had a satisfactory bacteriological quality (few or no coliforms, no pathogens). The sensoryevaluation offresh cheese showed that products made with the starter composed of Lactococcus lactis subsp.lactis, L. lactis subsp. lactis var. diacetylactis and Lactobacillus casei subsp. casei were more appreciated than those made with other starters or those obtained from the market

The application of multiplex fluorimetric sensor for the analysis of flavonoids content in the medicinal herbs family Asteraceae, Lamiaceae, Rosaceae

BACKGROUND: The aim of our research work was to quantify total flavonoid contents in the leaves of 13 plant species family Asteraceae, 8 representatives of family Lamiaceae and 9 plant species belonging to familyRosaceae, using the multiplex fluorimetric sensor. Fluorescence was measured using optical fluorescence apparatus Multiplex(R) 3 (Force-A, France) for non-destructive flavonoids estimation. The content of total flavonoids was estimated by FLAV index (expressed in relative units), that is deduced from flavonoids UV absorbing properties. RESULTS: Among observed plant species, the highest amount of total flavonoids has been found in leaves ofHelianthus multiflorus (1.65 RU) and Echinops ritro (1.27 RU), Rudbeckia fulgida (1.13 RU) belonging to the family Asteraceae. Lowest flavonoid content has been observed in the leaves of marigold (Calendula officinalis) (0.14 RU) also belonging to family Asteraceae. The highest content of flavonoids among experimental plants of family Rosaceae has been estimated in the leaves of Rosa canina (1.18 RU) and among plant species of family Lamiaceae in the leaves of Coleus blumei (0.90 RU). CONCLUSIONS: This research work was done as pre-screening of flavonoids content in the leaves of plant species belonging to family Asteraceae, Lamiaceae and Rosaceae. Results indicated that statistically significant differences (P > 0.05) in flavonoids content were observed not only between families, but also among individual plant species within one family

MVL-PLA2, a Snake Venom Phospholipase A2, Inhibits Angiogenesis through an Increase in Microtubule Dynamics and Disorganization of Focal Adhesions

Integrins are essential protagonists of the complex multi-step process of angiogenesis that has now become a major target for the development of anticancer therapies. We recently reported and characterized that MVL-PLA2, a novel phospholipase A2 from Macrovipera lebetina venom, exhibited anti-integrin activity. In this study, we show that MVL-PLA2 also displays potent anti-angiogenic properties. This phospholipase A2 inhibited adhesion and migration of human microvascular-endothelial cells (HMEC-1) in a dose-dependent manner without being cytotoxic. Using Matrigel™ and chick chorioallantoic membrane assays, we demonstrated that MVL-PLA2, as well as its catalytically inactivated form, significantly inhibited angiogenesis both in vitro and in vivo. We have also found that the actin cytoskeleton and the distribution of αvβ3 integrin, a critical regulator of angiogenesis and a major component of focal adhesions, were disturbed after MVL-PLA2 treatment. In order to further investigate the mechanism of action of this protein on endothelial cells, we analyzed the dynamic instability behavior of microtubules in living endothelial cells. Interestingly, we showed that MVL-PLA2 significantly increased microtubule dynamicity in HMEC-1 cells by 40%. We propose that the enhancement of microtubule dynamics may explain the alterations in the formation of focal adhesions, leading to inhibition of cell adhesion and migration

Detection of Potato virus Y in Pepper by ELISA-RT-nested PCR

We describe a reliable method to improve the detection of potato virus Y in pepper (Capsicum annuum L.), based on nested PCR performed after an ELISA-RT-PCR stage. Many problems were overcome by this approach, particularly those due to PCR inhibitory compounds which seem to be abundant in pepper

Préparation du fromage frais à partir du lait recombiné

Le but de cette étude a été d'évaluer les possibilités de préparation du fromage frais à partir du lait recombiné qui a été pasteurisé puis conservé pendant une nuit à 6°C pour faciliter la réhydratation. Le lait a été ensuite inoculé avec le levain constitué à parts égales de L. lactis subsp. lactis, L. lactis subsp. lactis var. diacetylactis et L. casei subsp casei à raison de 3% puis maintenu entre 30 et 37°C pour activer la fermentation. À pH 5,0 à 5,5, la présure a été ajoutée puis le moulage a été réalisé à température ambiante lorsque le pH a atteint une valeur comprise entre 4,3 .. 5,0. L'adoption de cette procédure normalisée de préparation du fromage frais a donné lieu à des produits de composition physico-chimique régulière et de qualité microbiologique satisfaisante. L'analyse sensorielle du fromage frais a montré que les produits élaborés à partir du lait recombiné uniquement (100%), ont été moins appréciés que ceux préparés à partir du lait recombiné additionné de 25 ou 50% de lait frais.Manufacture of fresh cheese from recombined milkThis study was carried out to evaluate the possibility of making fresh cheese from recombined milk. For this preparation, recombined milk was pasteurized and cooled overnight at 6°C to improve the powder rehydration. Then, milk was inoculated with 3% of a lactic starter composed of L.lactis subsp. lactis, L. lactis subsp.lactis var. diacetylactis and L. ca sei subsp. casei, and kept at 30 - 3TC to activate fermentation. At pH 5,0 - 5,5, the rennet was added and moulding was realized at ambient temperature when the pH reached a value of 4,3 to 5,0. Standardization of the processing gave fresh cheese with a regular chemical composition and a satisfactory microbiological quality. The sensory evaluation of fresh cheese showed that the products made with 100% recombined milk were less appreciated than those prepared from recombined milk added up with 20 to 25% fresh milk

Préparation du fromage frais à partir du lait recombiné

Le but de cette étude a été d'évaluer les possibilités de préparation du fromage frais à partir du lait recombiné qui a été pasteurisé puis conservé pendant une nuit à 6°C pour faciliter la réhydratation. Le lait a été ensuite inoculé avec le levain constitué à parts égales de L. lactis subsp. lactis, L. lactis subsp. lactis var. diacetylactis et L. casei subsp casei à raison de 3% puis maintenu entre 30 et 37°C pour activer la fermentation. À pH 5,0 à 5,5, la présure a été ajoutée puis le moulage a été réalisé à température ambiante lorsque le pH a atteint une valeur comprise entre 4,3 .. 5,0. L'adoption de cette procédure normalisée de préparation du fromage frais a donné lieu à des produits de composition physico-chimique régulière et de qualité microbiologique satisfaisante. L'analyse sensorielle du fromage frais a montré que les produits élaborés à partir du lait recombiné uniquement (100%), ont été moins appréciés que ceux préparés à partir du lait recombiné additionné de 25 ou 50% de lait frais.Manufacture of fresh cheese from recombined milkThis study was carried out to evaluate the possibility of making fresh cheese from recombined milk. For this preparation, recombined milk was pasteurized and cooled overnight at 6°C to improve the powder rehydration. Then, milk was inoculated with 3% of a lactic starter composed of L.lactis subsp. lactis, L. lactis subsp.lactis var. diacetylactis and L. ca sei subsp. casei, and kept at 30 - 3TC to activate fermentation. At pH 5,0 - 5,5, the rennet was added and moulding was realized at ambient temperature when the pH reached a value of 4,3 to 5,0. Standardization of the processing gave fresh cheese with a regular chemical composition and a satisfactory microbiological quality. The sensory evaluation of fresh cheese showed that the products made with 100% recombined milk were less appreciated than those prepared from recombined milk added up with 20 to 25% fresh milk

The effect of tobacco, XPC, ERCC2 and ERCC5 genetic variants in bladder cancer development

<p>Abstract</p> <p>Background</p> <p>In this work, we have conducted a case-control study in order to assess the effect of tobacco and three genetic polymorphisms in <it>XPC, ERCC2 and ERCC5 </it>genes (rs2228001, rs13181 and rs17655) in bladder cancer development in Tunisia. We have also tried to evaluate whether these variants affect the bladder tumor stage and grade.</p> <p>Methods</p> <p>The patients group was constituted of 193 newly diagnosed cases of bladder tumors. The controls group was constituted of non-related healthy subjects. The rs2228001, rs13181 and rs17655 polymorphisms were genotyped using a polymerase chain reaction-restriction fragment length polymorphism technique.</p> <p>Results</p> <p>Our data have reported that non smoker and light smoker patients (1-19PY) are protected against bladder cancer development. Moreover, light smokers have less risk for developing advanced tumors stage. When we investigated the effect of genetic polymorphisms in bladder cancer development we have found that ERCC2 and ERCC5 variants were not implicated in the bladder cancer occurrence. However, the mutated homozygous genotype for XPC gene was associated with 2.09-fold increased risk of developing bladder cancer compared to the control carrying the wild genotype (p = 0.03, OR = 2.09, CI 95% 1.09-3.99). Finally, we have found that the XPC, ERCC2 and ERCC5 variants don't affect the tumors stage and grade.</p> <p>Conclusion</p> <p>These results suggest that the mutated homozygous genotype for XPC gene was associated with increased risk of developing bladder. However we have found no association between rs2228001, rs13181 and rs17655 polymorphisms and tumors stage and grade.</p