Entamoeba histolytica

7 Iron-Sulfur Cluster Biosynthesis and the Evolution of Mitochondria 

Eukaryotic cells have several internal compartments, each of which has a discrete metabolic function. There are different evolutionary scenarios attempting to explain the history of these organelles and the selection pressure that propelled their genesis. To further this aim, an important point is to define the essential functions of the organelles conserved in organisms amongst all branches of the eukaryotic tree. 

Mitochondria were derived some two billion years ago from endosymbi-otic bacteria, most likely of a-proteobacterial origin (Gray et al. 1999 Kurland and Andersson 2000). Modern mitochondria have evolved into a 

The origin of eukaryotic cells and particularly mitochondria is an old but still hotly debated topic. The endosymbiotic model proposed the 

The essential character of the FeS cluster assembly machinery and its conservation in all eukaryotes suggests that FeS cluster assembly might have been among the original and essential functions of the ancestral endosymbiont, which gave rise to mitochondria and related organelles. If so, eubacte-rial FeS cluster assembly should provide a functional advantage in comparison with the archaebacterial machinery. At the same time, the archaebacterial host should have been dependent on the function of the 

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Umbellatine was examined by Gupta and Kahali, who found that it killed Paramoecium at 1 in 500 and Leishmania tropica at 1 in 50,000, but did not inhibit L. donovani or Entamoeba histolytica at 1 in 10,000. It remembles berberine in the nature and range of its pharmacological activity but is more active in producing cardiovascular response and is possibly more potent in the treatment of oriental sore. 

Coulthard for amoebicidal action. Each kind of activity increases to a peak as the series is ascended and then diminishes. In the 0-n-alkyl series the peak is at 0-n-butylharmol for Bacillus typhosus, at 0-n-amyl-harmol for Staphylococcus aureus and at 0-n-nonylharmol for Entamoeba histolytica. In the 0-io-diethylaminoalkyl series the peak for B. typhosus is at 0-to-diethylaminononylharmol. No trypanocidal or anti-malarial action was observed in a selection of the compounds tested. ... 

Entamoeba histolytica is an anaerobic rhizopod that occurs in tropical and subtropical areas. It can cause intestinal and extraintestinal manifestations. It is transmitted orally by ingestion of cysts that develop into trophozoites in the large intestine. Amebic trophozoites release several cytolytic factors, e.g. amoe-bapore, which enable the parasite to invade tissue. In intestinal amoebiasis, E. histolyticatrophozoites invade the intestinal mucosa, causing a form of ulcerative colitis with bloody and mucous diarrhoea. Extraintestinal manifestation of amebiasis results in abscess formation, usually in the liver but sometimes in the brain. 

Unmodified antisense PNA oligomers were also recently shown to downregu-late targeted genes in an amoeba (Entamoeba histolytica) [68]. These results suggest the potential development of PNA as a new class of antimicrobial drugs. 

Stock R. P., Olvera A., Sanchez R., Saralegui a., Scarei S., Sanchez-Lopez R., Ramos M.A., Boeea L.C., Benatti U., Alagon a. Inhibition of gene expression in Entamoeba histolytica with anti-sense peptide nucleic acid oligomers. Nature Biotechnol. 2001, 19 231-234. 

Bacteria are likely precipitants in many other cases including Escherichia coli, Salmonella species, Shigella species, Vibrio cholerae, and Clostridium difficile. The term dysentery has often been used to describe some of these bacterial infections when associated with serious occurrences of bloody diarrhea. Additionally, acute diarrheal conditions can be prompted by parasites-protozoa such as Entamoeba histolytica, Microsporidium, Giardia lamblia, and Cryptosporidium parvum. Most of these infectious agents can be causes of traveler s diarrhea, a common malady alflicting travelers worldwide. It usually occurs during or just after travel subsequent to the ingestion of fecally-contaminated food or water. It has an abrupt onset but usually subsides within 2 to 3 days. 

Abscesses suspected of being caused by Entamoeba histolytica may be aspirated, and the material may be submitted to the laboratory. 

Belley, A., Keller, K., Grove, J. and Chadee, K. (1996) Interaction of LS174T human colon cancer cell mucins with Entamoeba histolytica an in vitro model for colonic disease. Gastroenterology 111, 1484—1492. 

Consider parasites Giardia Entamoeba histolytica Strongyloides stercoralis Cryptosporidium Cyclospora Isospora belli ... 

A. L. Elias, J. C. Carrero-Sanchez, H. Terrones, M. Endo, J. P. Laclette, M Terrones, Viability studies of pure carbon- and nitrogen-doped nanotubes with Entamoeba histolytica From amoebicidal to biocompatible structures, Small, vol. 3, pp. 1723-1729, 2007. 

Entamoeba histolytica — Euglena gracilis Cryptosporidium parvum... 

Acute intestinal amebiasis Due to Entamoeba histolytica as adjunct to amebicides. 

Amebiasis For the treatment of intestinal amebiasis and amebic liver abscess caused by Entamoeba histolytica in adults and pediatric patients older than 3 years of age. 

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