Encapsulation effects of galactomannans combined with xanthan on the survival of two lactic strains under simulated digestive hostilities

Galactomannans are the main component of locust bean gum from the fruit of the carob tree, Ceratonia siliqua L. They are a reserve of polysaccharides, found in the translucent endosperm of the seeds. They are designated as the best gels with thickening capacity and are, therefore, widely used as a natural food additive (E410) in many food, pharmaceutical and cosmetic preparations. In this study, we aim to exploit this gelling property of carob galactomannans in the microencapsulation of lactic bacteria in order to protect them from the negative effects of simulated digestive conditions. Two beneficial bacteria are used: Lactobacillus rhamnosus LBRE-LSAS and Bifidobacterium animalis subsp. lactis Bb12. Their survival in the free state or encapsulated in pure carob galactomannan gel combined with xanthan, was determined after residence in simulated in vitro digestive conditions (gastric: pH 2, pepsin 3 g/l and intestinal: bile 0.3%: W/V, pH 6.5. The results obtained show that gel encapsulation of carob galactomannans combined with xanthan improves the survival of these two beneficial strains to simulated digestive hostilities. the loss under gastric conditions 36.79% (3.55 log CFU/mL) for the non-encapsulated cells and only 12% (1.2 log CFU/mL) for the encapsulated ones. However, galactomannans alone do not appear to be effective in keeping a minimum of 106 bacterial cells viable when confronted with the hostile conditions of the digestive tract where they will be called upon to exert their positive effect on health. DOI: http://dx.doi.org/10.5281/zenodo.704863

Profil étiologique des microangiopathies thrombotiques rénales au Centre Hospitalier et Universitaire de Tunis: Etiological profile of renal thrombotic microangiopathy in Tunis University Hospital

Context and objective. Renal thrombotic microangiopathy (TMA) is a histological lesion that can be observed in several pathological settings. The present study aimed to describe the different etiological contexts in which TMA has been observed and provide particularities. Methods. A retrospective and descriptive study over a 16-year period, from January 2000 to January 2016 was conducted at the Tunis University Hospital. All patients aged over 16 years and presenting with TMA at renal biopsy were analyzed. Results. 100 cases of renal TMA were collected. The mean age of patients at the time of renal biopsy was 38.5 ± 12.9 years. The clinical picture was dominated by hypertension observed in 70 patients. Results of the laboratory investigations were as follows: kidney injury was noted in 92 patients and biological TMA was observed in 10 patients. At the renal biopsy, arteriolar TMA was seen in all patients and glomerular TMA was seen in 15 patients. Seventy-three patients reached end stage renal disease. TMA was observed mainly in association with glomerular nephropathy outside lupus nephropathy in 47 cases, lupus nephropathy in 19 cases, malignant hypertension in 18 cases and post-renal transplantation in 9 cases. TMA was related to atypical hemolytic uremic syndrome in one case and 6 sporadic cases were observed. Conclusion. Renal TMA has been observed in several pathological situations. Comparative studies with matched control cases in each group but without TMA lesions should be performed to identify risk factors for developing TMA and the influence of TMA on renal prognosis in each etiological setting. Contexte et objectif. La microangiopathie thrombotique (MAT) rénale est une lésion histologique caractérisée par la présence de microthrombi obstruant les vaisseaux de la microcirculation rénale. Actuellement, les patients atteints de MAT rénale sont répartis en fonction du contexte étiologique. L’objectif de la présente étude était de décrire les différents contextes pathologiques au cours desquels une MAT rénale a été observée. Méthodes. Il s’agissait d’une étude documentaire (16 ans). L’étude a inclus tous les patients adultes ayant des lésions de MAT à la ponction biopsie rénale (PBR). Résultats. Parmi 3240 PBR réalisées, la MAT a été observée chez 100 patients soit une incidence moyenne de 6,7 cas/an. L’âge moyen était de 38,5+/-12,9 ans avec une prédominance masculine. Les lésions de MAT rénale ont été associées à plusieurs contextes pathologiques : les néphropathies glomérulaires (47%), les néphropathies lupiques (19%), l’HTA maligne (18%), post transplantation rénale (9%), postgreffe de cellules souches hématopoïétiques (1%), post partum (2%), un contexte néoplasique (1%), une origine médicamenteuse (1%), un syndrome des antiphospholipides primaire (1%), et un syndrome hémolytique et urémique (1%). Conclusion. La MAT rénale est fréquemment secondaire et s’associe à plusieurs contextes pathologiques. Cependant un SHUa/PTT sous-jacents devrait toujours être recherchés