228 research outputs found
Effect of various stress factors on mitochondrial processes of pathogenic protists
No full textMitochondria perform various important functions in cells. They are the main site of energy metabolism, biosynthetic and regulatory processes, and the center of iron metabolism. Additionally, mitochondria are also the central organelle responsible for the production of potentially dangerous reactive oxygen species and possess a self-destructive arsenal capable of inducing whole-cell apoptosis. This single organelle thus controls the fate of the entire cell. Given these facts, this organelle has become the focus of interest for many scientists and pharmaceutical companies developing drugs targeting mitochondria. During evolution, unicellular parasites have evolved several mechanisms to survive, defend themselves and reproduce in the hostile environment of their host. One of these mechanisms is the ability to adapt its mitochondrial metabolism to maintain the viability of the whole cell. This work focuses on mitochondria from two different perspectives: First, concerning the phenomenon of nutritional immunity, we studied the effect of iron and copper deprivation on the mitochondria of the "brain-eating" amoeba Naegleria fowleri. Proteomic analysis of cells pre-incubated with specific chelators, together with the determination of several enzyme activities and measurements of oxygen consumption,..
Vliv různých stresových faktorů na mitochondriální procesy patogenních protistů
Get PDFMitochondrie plní v buňkách různé důležité funkce. Jsou hlavním místem energetického metabolismu, biosyntetických a regulačních procesů a také centrem metabolismu železa. Kromě toho jsou mitochondrie také ústřední organelou odpovědnou za produkci potenciálně nebezpečných reaktivních forem kyslíku a disponují sebedestruktivním arzenálem schopným vyvolat apoptózu celé buňky. Tato jediná organela tak řídí osud celé buňky. Vzhledem k těmto skutečnostem se tato organela stala středem zájmu mnoha vědců a farmaceutických společností vyvíjejících léčiva cílená na mitochondrie. Jednobuněční parazité si během evoluce vyvinuli několik mechanismů, jak přežít, bránit se a rozmnožovat se v nepřátelském prostředí svého hostitele. Jedním z těchto mechanismů je schopnost přizpůsobit svůj mitochondriální metabolismus k udržení životaschopnosti celé buňky. Tato práce se zaměřuje na mitochondrie ze dvou různých hledisek: Za prvé, s ohledem na fenomén nutriční imunity, jsme studovali vliv deprivace železa a mědi na mitochondrie "mozkožravé" améby Naegleria fowleri. Proteomická analýza buněk předem preinkubovaných se specifickými chelátory, spolu se stanovením aktivit enzymů a měřením spotřeby kyslíku ukázala, že mitochondrie N. fowleri se těmto limitujícím faktorům přizpůsobují upregulací alternativních složek...Mitochondria perform various important functions in cells. They are the main site of energy metabolism, biosynthetic and regulatory processes, and the center of iron metabolism. Additionally, mitochondria are also the central organelle responsible for the production of potentially dangerous reactive oxygen species and possess a self-destructive arsenal capable of inducing whole-cell apoptosis. This single organelle thus controls the fate of the entire cell. Given these facts, this organelle has become the focus of interest for many scientists and pharmaceutical companies developing drugs targeting mitochondria. During evolution, unicellular parasites have evolved several mechanisms to survive, defend themselves and reproduce in the hostile environment of their host. One of these mechanisms is the ability to adapt its mitochondrial metabolism to maintain the viability of the whole cell. This work focuses on mitochondria from two different perspectives: First, concerning the phenomenon of nutritional immunity, we studied the effect of iron and copper deprivation on the mitochondria of the "brain-eating" amoeba Naegleria fowleri. Proteomic analysis of cells pre-incubated with specific chelators, together with the determination of several enzyme activities and measurements of oxygen consumption,...Katedra parazitologieDepartment of ParasitologyPřírodovědecká fakultaFaculty of Scienc
Monkey malaria in the Netherlands in a traveler from Malaysia:A sporadic imported malaria which can evolve seriously
No full textEen 38-jarige Maleisische arbeider uit de Rotterdamse haven kreeg een week na aankomst uit Maleisië in Nederland piekende koorts en malaiseklachten. Ook was hij icterisch. Onderzoek naar malaria was positief, maar de morfologie van de malariaparasieten was ongewoon. Op basis van het recente verblijf in Maleisisch Borneo en de vreemde parasietenmorfologie, werd gedacht dat patiënt een infectie met Plasmodium knowlesi had. Hij werd behandeld met chloroquine, waarna de parasieten binnen 40 h uit het bloed verdwenen waren. Moleculair onderzoek bevestigde de P. knowlesi-infectie. P. knowlesi veroorzaakt voornamelijk malaria bij apen (makaken), maar wordt sinds kort steeds vaker herkend als veroorzaker van al dan niet ernstige malaria bij mensen in Zuidoost-Azië. P. knowlesi-infecties kunnen op basis van de morfologische kenmerken gemakkelijk verward worden met Plasmodium malariae-infecties. [...]<br/
Monkey malaria in the Netherlands in a traveler from Malaysia:A sporadic imported malaria which can evolve seriously
No full textEen 38-jarige Maleisische arbeider uit de Rotterdamse haven kreeg een week na aankomst uit Maleisië in Nederland piekende koorts en malaiseklachten. Ook was hij icterisch. Onderzoek naar malaria was positief, maar de morfologie van de malariaparasieten was ongewoon. Op basis van het recente verblijf in Maleisisch Borneo en de vreemde parasietenmorfologie, werd gedacht dat patiënt een infectie met Plasmodium knowlesi had. Hij werd behandeld met chloroquine, waarna de parasieten binnen 40 h uit het bloed verdwenen waren. Moleculair onderzoek bevestigde de P. knowlesi-infectie. P. knowlesi veroorzaakt voornamelijk malaria bij apen (makaken), maar wordt sinds kort steeds vaker herkend als veroorzaker van al dan niet ernstige malaria bij mensen in Zuidoost-Azië. P. knowlesi-infecties kunnen op basis van de morfologische kenmerken gemakkelijk verward worden met Plasmodium malariae-infecties. [...]<br/
Is paromomycin the drug of choice for eradication of Blastocystis in adults?
No full textBlastocystis is a protozoan parasite of controversial clinical significance that is often detected in stools of patients with gastrointestinal complaints. Patients infected with Blastocystis and persistent, unexplained gastrointestinal complaints are often treated with the intention to eradicate Blastocystis. However, there is no consensus on the most effective drug. We performed a retrospective follow-up study with a large cohort of patients in which the natural disease course and efficacy of treatment with either paromomycin, clioquinol, or metronidazole were evaluated. With an eradication rate of 77 %, treatment with paromomycin appeared significantly more effective than treatment with clioquinol (38 %), metronidazole (38 %), or no treatment (22 %). This study showed that (1) Blastocystis was frequently observed in the stools of our patient group (34 %), (2) spontaneous clearance of Blastocystis infections occurred only in a small proportion of patients (22 %), and therefore (3) drug treatment is required for more efficient eradication of Blastocystis. Paromomycin exhibited superior performance in comparison to both metronidazole and clioquinol
Surprising variety in energy metabolism within Trypanosomatidae
No full textThe metabolism of Trypanosomatidae differs significantly between distinct species and can even be completely different between various life-cycle stages of the same species. It has been proposed that differences in energy metabolism are related to differences in nutrient supply in the environments of the various trypanosomatids. However, the literature shows that availability of substrates does not dictate the type of energy metabolism of trypanosomatids, as Trypanosoma theileri, Trypanosoma lewisi and African trypanosomes all live in the bloodstream of their mammalian host, but have surprisingly large differences in metabolism. Furthermore, in trypanosomatids no obvious relationship exists between energy metabolism and phylogeny or mode of transmission. We provide an overview of the metabolic capacities in the energy metabolism of distinct trypanosomatids, and suggest that these can be divided into four different metabolic categories of increasing complexity
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