Bionomics of Aphidius (Hymenoptera: Aphidiidae)

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Influence of non-toxinogenic strains of Clostridium difficile with hemolytic activity on cell morphology in mouse fibroblasts

Bakterija Clostridium difficile je normalno prisotna v naravi in prebavilih sesalcev. Je po Gramu pozitivna, anaerobna, sporogena bakterija. Spore so zelo odporne proti izsuševanju, kemikalijam ter ekstremnim temperaturam. Najpogosteje se okužijo starejši hospitalizirani ljudje, ki se jim poruši ravnovesje v črevesni flori, običajno zaradi daljšega zdravljenja z antibiotiki. Sevi, ki povzročajo bolezen, proizvajajo toksine, med katerimi sta najpomembnejša toksin A in toksin B. V diplomski nalogi smo se osredotočili na vpliv netoksinogenih sevov bakterije Clostridium difficile s hemolitično aktivnostjo na citoskelet mišjih fibroblastov. V raziskavi smo uporabili celice McCoy, ki smo jih tretirali s supernatantom, barvali aktinske filamente in jedra ter opazovali učinek na aktinskem citoskeletu s konfokalnim mikroskopom. Ugotovili smo, da je prišlo pri celicah tretiranih s supernatantom s hemolitično aktivnostjo do določenih sprememb, predvsem na aktinskem citoskeletu, medtem ko na jedrih ni bilo večjih razlik. Spremembe so bile vidne na aktinskih filamentih, ki so bili prekinjeni in združeni v skupke.Clostridium difficile is an anaerobic, Gram-positive bacterium which is usually present in environment and often resides in the gut of mammals. The bacteria forms spores that are resistant to desiccation, chemicals and extreme temperatures. Elderly hospitalized patients with damaged gut microbiota due to prolonged antibiotic treatment are the main population at risk. Strains which cause disease produce toxins. The most important toxins are toxin A and toxin B. In this work we were focusing on the influence of non-toxinogenic strains of Clostridium difficile with hemolytic activity on the cytoskeleton of mice fibroblasts. McCoy cells were treated with bacterial culture supernatant. Actin filaments and nucleuses were stained and the effect on the actin cytoskeleton was observed with confocal microscope. We found some changes on the cells that were treated with supernatant that has hemolytic activity, especially on actin cytoskeleton, but there were no essential modifications on nucleuses