In vitro effects of isoprinosine and of a dipeptide methyl ester on Echinococcus multilocularis.

International audienceA protoscoleces/vesicles in vitro maintenance test with assessment of viability by eosin exclusion was used to evaluate the quantitative and qualitative activities of isoprinosine, its active component inosine and the dipeptide methylester L-Phe-Phe-OMe on isolated protoscoleces of Echinococcus multilocularis for 24 and 48 h. Isoprinosine and inosine showed dose- and time-dependent activity, the latter displaying a more rapid effect than the former. A high activity was shown with L-Phe-Phe-OMe, when compared to praziquantel. Ultrastructural alterations were much more striking with L-Phe-Phe-OMe, with an effect similar to that of praziquantel, whereas the chemotherapeutic activity of inosine and isoprinosine appeared to be directed against a metabolic target, with a lethal effect not immediately visible at the ultrastructural level. Thus, the previously reported in vivo activities of these drugs result largely from a direct effect on the parasite

Purification and Characterization of the Alkaline Phosphatase from Echinococcus granulosus Cyst Membranes

International audienceThe purification to homogeneity and the characterization of Echinococcus granulosus alkaline phosphatase (AP; EC 3.1.3.1) from hydatid cyst membranes are described. After n-butanol extraction, the parasite enzyme was sequentially purified by affinity chromatography on concanavalin A-sepharose followed by gel filtration. The purified protein (210 kDa) had a tetrameric structure composed of 4 56-kDa subunits. Its isoelectric point (4.8) and its kinetic parameters were determined (Km = 0.24 ± 0.05 mmol/L; Vm = 173 ± 21 nmol/min/mg protein for p-nitrophenylphosphate). The parasite enzyme differed from the host liver enzyme in its thermal stability, optimum reaction temperature, optimum pH, and catalytic parameters, but not in its apparent molecular weight. Furthermore, sera from patients infected with E. granulosus recognized the parasite AP on immunoblots, whereas uninfected controls were negative. These results as well as the role of this enzyme in the host-parasite relationship emphasize its potential importance as a diagnostic and prognostic antigen in the monitoring of hydatid infection

Use of a non-adherent cell culture system for testing the effect of 2',3'-dideoxyinosine against Cryptosporidium parvum

International audienceThe in vitro cultivation of Cryptosporidium parvum in the non-adherent cell line THP-1 was evaluated for its capability as a useful additional model to investigate the effect of drugs on this parasite. The purine analog antiviral 2',3'-dideoxyinosine (ddI) was evaluated and compared to the reference molecule paromomycin in sequential 24 hour experiments beginning at 24 and 72 hour post-infection. The ability of this technique to evaluate the various parasite stages showed that ddI displayed a dose-dependent efficacy especially on the trophozoite and sexual stages. Paromomycin displayed a lower efficacy than previously reported. Both drugs induced a decrease in the number of multiparasitized cells. These results indicate that the purine salvage pathway should be a key chemotherapeutic target against C. parvum

An Oral Recombinant Vaccine in Dogs against Echinococcus granulosus, the Causative Agent of Human Hydatid Disease: A Pilot Study

Dogs are the main source of human cystic echinococcosis. An oral vaccine would be an important contribution to control programs in endemic countries. We conducted two parallel experimental trials in Morocco and Tunisia of a new oral vaccine candidate against Echinococcus granulosus in 28 dogs. The vaccine was prepared using two recombinant proteins from adult worms, a tropomyosin (EgTrp) and a fibrillar protein similar to paramyosin (EgA31), cloned and expressed in a live attenuated strain of Salmonella enterica serovar typhimurium

Microsporum canis (un dermatophyte responsable d'infections zoonotiques)

LYON1-BU Santé (693882101) / SudocSudocFranceF

LA GALE ET SON TRAITEMENT

LYON1-BU Santé (693882101) / SudocSudocFranceF

La Toxoplasmose congénitale (cas de l'uvéite à Toxoplasma gondii)

LYON1-BU Santé (693882101) / SudocSudocFranceF

Les Pathologies dues à Ctenocephalides felis et leurs prises en charge à l'officine chez le chat et chez l'homme

LYON1-BU Santé (693882101) / SudocSudocFranceF

DONNEES RECENTES SUR ENTEROBIUS VERMICULARIS

LYON1-BU Santé (693882101) / SudocSudocFranceF

La Maladie de lyme

LYON1-BU Santé (693882101) / SudocSudocFranceF