Axenic culture of Giardia lamblia in TYI-S-33 Medium Supplemented with Bile
Available from: Raúl Argüello-García
- "Trophozoite Cultures, Growth of ABZ-Resistant Clones and Obtention of H 2 O 2 -Resistant Trophozoites Giardia duodenalis trophozoites of the WB strain (ATCC#30957) and ABZ-resistant clones were maintained in TYI-S-33 medium supplemented with 10% adult bovine serum (HyClone) and antibiotic/antimycotic solution (Thermo, USA) at 37 • C (Keister, 1983) in 4.5 mL screw-capped vials. ABZ-resistant trophozoites were selected by continuous subculture under increasing sublethal concentrations of ABZ (Sigma cat. "
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ABSTRACT: The control of Giardia duodenalis infections is carried out mainly by drugs, among these albendazole (ABZ) is commonly used. Although the cytotoxic effect of ABZ usually involves binding to β-tubulin, it has been suggested that oxidative stress may also play a role in its parasiticidal mechanism. In this work the effect of ABZ in Giardia clones that are susceptible or resistant to different concentrations (1.35, 8, and 250 μM) of this drug was analyzed. Reactive oxygen species (ROS) were induced by ABZ in susceptible clones and this was associated with a decrease in growth that was alleviated by cysteine supplementation. Remarkably, ABZ-resistant clones exhibited partial cross-resistance to H 2 O 2, whereas a Giardia H 2 O 2-resistant strain can grow in the presence of ABZ. Lipid oxidation and protein carbonylation in ABZ-treated parasites did not show significant differences as compared to untreated parasites; however, ABZ induced the formation of 8OHdG adducts and DNA degradation, indicating nucleic acid oxidative damage. This was supported by observations of histone H2AX phosphorylation in ABZ-susceptible trophozoites treated with 250 μM ABZ. Flow cytometry analysis showed that ABZ partially arrested cell cycle in drug-susceptible clones at G2/M phase at the expense of cells in G1 phase. Also, ABZ treatment resulted in phosphatidylserine exposure on the parasite surface, an event related to apoptosis. All together these data suggest that ROS induced by ABZ affect Giardia genetic material through oxidative stress mechanisms and subsequent induction of apoptotic-like events.
Frontiers in Microbiology 08/2015; 6(800). DOI:10.3389/fmicb.2015.00800 · 3.99 Impact Factor
Available from: Alejandra Rojas-Molina
- "E. histolytica strain HM-1:IMSS, T. vaginalis strain GT-13, and G. lamblia strain 0989:IMSS were used in this study. E. histolytica and T. vaginalis were grown in PEHPS medium (Said-Fernández et al., 1988), and G. lamblia in TYI-S-33 supplemented with bile (Keister, 1983). All three species were subcultured three times each week. "
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ABSTRACT: Background: Crataegus mexicana, Hyptis albida, Larrea tridentata, Ocimum baislicum, Prunus serotina, and Smilax spp. are used in Mexican traditional medicine to treat respiratory and gastrointestinal diseases such as flu, cough, diarrhea, dysentery, and other parasitic or microbial infections. Therefore this study was aimed at the pharmacological prospection of these plants against eleven bacterial species and three amitochondrial protist pathogens. Material and methods: The fruits or aerial parts of C. mexicana, H. albida, L. tridentata, O. baislicum, P. serotina, and Smilax spp. were extracted with different solvents. The antibacterial properties of organic and aqueous extracts of these plants were determined by the microdilution method and the microplate alamar blue assay against Stenotrophomonas maltophilia, Escherichia coli, Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, Enterobacter cloacae, Staphylococcus aureus, methicillin-resistant S. aureus, Listeria monocytogenes, Enterococcus faecalis, and Mycobacterium tuberculosis, whereas anti-protozoal activities of extracts were evaluated by a vial micro-assay against strains of Entamoeba histolytica, Trichomonas vaginalis, and Giardia lamblia. Results: H. albida, Smilax spp, and C. mexicana showed good activity against the Gram-positive strains, S. aureus, methicillin-resistant S. aureus, and E. faecalis. Four extracts (C. mexicana, H. albida, O. basilicum, and L. tridentata) showed good activity against E. histolytica, T. vaginalis, and G. lamblia. Conclusion: The extracts of these six medicinal plants could be a source for new antibacterial and antiprotozoal drugs. For this reason they are currently under investigation to isolate and characterize their active compounds.
African Journal of Traditional, Complementary and Alternative Medicines 07/2015; 12(3):104-112. DOI:10.4314/ajtcam.v12i3.13 · 0.56 Impact Factor
Available from: James Anthony Cotton
- "Giardia NF trophozoites were originally obtained from a water sample during an outbreak of giardiasis in Newfoundland, Canada , while Giardia GS/M clone H7 trophozoites were obtained from ATCC (50581) as previously described . Trophozoites were grown axenically in 15 mL polystyrene tubes (Becton-Dickinson Falcon) in Keister’s modified TYI-S-33 medium ,  supplemented with piperacillin (Sigma-Aldrich) and used at peak density culture. "
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ABSTRACT: Giardia duodenalis (syn. G. intestinalis, G. lamblia) is a predominant cause of waterborne diarrheal disease that may lead to post-infectious functional gastrointestinal disorders. Although Giardia-infected individuals could carry as much as 106 trophozoites per centimetre of gut, their intestinal mucosa is devoid of overt signs of inflammation. Recent studies have shown that in endemic countries where bacterial infectious diseases are common, Giardia infections can protect against the development of diarrheal disease and fever. Conversely, separate observations have indicated Giardia infections may enhance the severity of diarrheal disease from a co-infecting pathogen. Polymorphonuclear leukocytes or neutrophils (PMNs) are granulocytic, innate immune cells characteristic of acute intestinal inflammatory responses against bacterial pathogens that contribute to the development of diarrheal disease following recruitment into intestinal tissues. Giardia cathepsin B cysteine proteases have been shown to attenuate PMN chemotaxis towards IL-8/CXCL8, suggesting Giardia targets PMN accumulation. However, the ability of Giardia infections to attenuate PMN accumulation in vivo and how in turn this effect may alter the host inflammatory response in the intestine has yet to be demonstrated. Herein, we report that Giardia infection attenuates granulocyte tissue infiltration induced by intra-rectal instillation of Clostridium difficile toxin A and B in an isolate-dependent manner. This attenuation of granulocyte infiltration into colonic tissues paralled decreased expression of several cytokines associated with the recruitment of PMNs. Giardia trophozoite isolates that attenuated granulocyte infiltration in vivo also decreased protein expression of cytokines released from inflamed mucosal biopsy tissues collected from patients with active Crohn's disease, including several cytokines associated with PMN recruitment. These results demonstrate for the first time that certain Giardia infections may attenuate PMN accumulation by decreasing the expression of the mediators responsible for their recruitment.
PLoS ONE 10/2014; 9(10):e109087. DOI:10.1371/journal.pone.0109087 · 3.23 Impact Factor
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