Probiotic supplementation promotes calcification in Danio rerio larvae: a molecular study.

A growing number of studies have been showing that dietary probiotics can exert beneficial health effects in both humans and animals. We previously demonstrated that dietary supplementation with Lactobacillus rhamnosus - a component of the human gut microflora - enhances reproduction, larval development, and the biomineralization process in Danio rerio (zebrafish). The aim of this study was to identify the pathways affected by L. rhamnosus during zebrafish larval development. Our morphological and histochemical findings show that L. rhamnosus accelerates bone deposition through stimulation of the expression of key genes involved in ossification, e.g. runt-related transcription factor 2 (runx2), Sp7 transcription factor (sp7), matrix Gla protein (mgp), and bone gamma-carboxyglutamate (gla) protein (bglap) as well as through inhibition of sclerostin (sost), a bone formation inhibitor. Western blot analysis of mitogen-activated protein kinase 1 and 3-(Mapk1 and Mapk3), which are involved in osteoblast and osteocyte differentiation, documented an increase in Mapk1 16 days post fertilization (dpf) and of Mapk3 23 dpf in individuals receiving L. rhamnosus supplementation. Interestingly, a reduction of sost detected in the same individuals suggests that the probiotic may help treat bone disorders.

[Calcified splenic abscess, colonic fistula and ascites in a chronic carrier of Salmonella typhi]. / Abcès splénique calcifié, fistule colique et ascite chez un porteur chronique de Salmonella typhi.

We report the unusual case of a patient with chronic carriage of Salmonella typhi who presented with partially calcified splenic abscess linked to colic fistula and ascitis. The colic fistula could be secondary to ischemic necrosis by left colon compression due to spleen large abscess. Fistula was evidenced by abdominal computed tomography scan and confirmed by barium enema. The possible etiologies of ascitis are either tuberculosis or ascitic peritonitis secondary to the fistulisation; nevertheless, the role of segmentary portal located hypertension cannot be completely excluded. The splenic abscess was probably due to Salmonella typhi which was only isolated from stool specimens. The calcified splenic abscess was the evidence that the infection had occurred first. In addition, the isolation of Salmonella typhi in stool cultures six months after the subject had returned from the Comores proved the chronic carriage. Treatment by splenectomy and left colectomy was successful in this patient.