Amoebicidal action

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. ... 

Diiodohydroxyquinoline is directly amoebicidal. It has activity against motile and cystic forms. It kills cyst forming trophozoites in intestine but has no tissue amoebicidal action. It is ineffective in extraintestinal amoebiasis. It is also effective in cyst passing patients. 

The amoebicidal action is used in the treatment of amoebic dysentery, which occurs endemically in tropical and subtropical... 

Iodine has also been used for the disinfection of swimming pool water. The concentration range in which it shows strong bactericidal, virucidal, or amoebicidal action is 5-50 mg/cm, leaving a 0.2-0.6 mg/dm residual iodine concentration. Traces of iodine or iodide ions are found in raw waters. The iodine is an essential trace element for humans. The adult daily requirement of iodine or iodide is 80-150 xg. Iodide content of the drinking water is sometimes checked to decide the amount of supplement needed. The iodide is usually supplied as a table-salt additive in areas where it is needed. As a matter of fact, the determination of iodine or iodide content of water samples is not needed very often. However, the titration or back titration of iodine content is an everyday trick in iodometric analytical procedures. 

Of the dichloroacetamides diloxanide furoate, clefamide, teclozan and etofamide the most frequently used agent is diloxanide furoate. It is the luminal amoebicide of choice in chronic intestinal amoebiasis, however it lacks efficacy acute intestinal amoebiasis. Its mechanism of action is unknown. Given orally, diloxanide is formed by bacterial hydrolases. Diloxanide is for 90% absorbed and then metabolized to diloxanide glucuronide. The remaining 10% remains in the intestine as the active drug. Diloxanide is generally well tolerated. Adverse effects include flatulence, nausea and abdominal cramps. 

The ipecacuanha root has three actions expectorant, emetic and amoebicidal. The expectorant action is due to the irritant effect of emetine and cephaeline on the gastrointestinal tract, which causes a reflex increase in the secretion of respiratory tract fluid. The dose is... 

A nitrogen mustard derivative of barbituric acid has been reported without antitumour data [206]. 5-Diazobarbituric anhydride (XLVI) has been found to be amoebicidal at 0-001 mg/ml vs. Endamoeba histolytica [207]. The inhibition is reversed by nucleotides, but not by the bases or nucleosides. It had previously been found that (XLVI) is a cytosine antagonist in the yeasts, Torula utilis and Saccharomyces cerevisiae Hansen [208]. This compound is prepared by the action of nitrous and nitric acids on 5-aminouracil-6-sulphonic acid [209], and as a cyclic derivative of a barbituric acid, it has quite different properties from the pyrimidinetriones. 

Therapeutic Uses of Ipecacuanha Alkaloids. Emetine is used in medicine as an emetic, and in small doses as an expectorant but for the latter purpose ipecacuanha itself, or one of its galenical preparations, is generally used. Emetine is chiefly of interest as a remedy for amoebic dysentery owing to its direct toxic action on Entamceba histolytica, for which purpose it is employed as the hydrochloride for injection, or in one of the insoluble forms, such as emetine bismuth iodide, for oral administration. Methods devised by Dobell et al. have been much used for testing amoebicidal agents in vitro, and show that emetine is much more toxic to Entamceba histolytica than its stereoisomeride woemetine, or than A -methylemetine or 0-methylpsychotrine, aU of which have been tried clinically and found inactive. Pyman and his collaborators have synthesised for trial as amoebicides four series of substanees, of which typical examples are represented by formulae A, B (and B ), C and D. Representatives of type A... 

Diseases caused by amoebae. Many useful new amoebicidal drugs have been found which exert their action by contact with colonies of amoebae, and on trophozoites present in the colonic lumen. Metronidazole (6.79)... 

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