Chu, D M; Miles, H; Toney, D; Ngyuen, C; Marciano-Cabral, F
The effect of 100 polar and 100 nonpolar plant extract materials obtained from Southeast Asia were evaluated for amebicidal activity in vitro against three species of Acanthamoeba. A. culbertsoni, A. castellanii, and A. polyphaga, the causative agents of granulomatous amebic encephalitis and amebic keratitis, were studied in vitro to determine whether the plant extracts exhibited amebicidal activity or induced encystment of the amebae. Of the 200 plant extracts tested, extracts obtained from three plants (Ipomoea sp., Kaempferia galanga, and Cananga odorata) were amebicidal for all three species of Acanthamoeba and a fourth extract prepared from Gastrochilus panduratum was lytic for A. polyphaga and growth-inhibitory for A. castellanii and A. culbertsoni. Three plant extracts induced encystment of all three species of Acanthamoeba. Select plant extracts were tested as well for tumoricidal activity against B103 neuroblastoma cells. Some plant extracts that exhibited tumoricidal activity for B103 cells were not amebicidal for Acanthamoeba spp. Additionally, the polar and nonpolar extracts that exhibited amebicidal activity were also tested for activity against primary murine peritoneal macrophage cultures. Plant extracts that demonstrated tumoricidal or amebicidal activity were not lytic for normal macrophage cultures. PMID:9766904
Santos, Israel Gomes de Amorim; Scher, Ricardo; Rott, Marilise Brittes; Menezes, Leociley Rocha; Costa, Emmanoel Vilaça; Cavalcanti, Sócrates Cabral de Holanda; Blank, Arie Fitzgerald; Aguiar, Jaciana dos Santos; da Silva, Teresinha Gonçalves; Dolabella, Silvio Santana
Amoebic keratitis and granulomatous amoebic encephalitis are caused by some strains of free-living amoebae of the genus Acanthamoeba. In the case of keratitis, one of the greatest problems is the disease recurrence due to the resistance of parasites, especially the cystic forms, to the drugs that are currently used. Some essential oils of plants have been used as potential active agents against this protist. Thus, the aim of this study was to determine the amebicidal activity of essential oils from plants of the genus Lippia against Acanthamoeba polyphaga trophozoites. To that end, 8 × 10(4) trophozoites were exposed for 24 h to increasing concentrations of essential oils from Lippia sidoides, Lippia gracilis, Lippia alba, and Lippia pedunculosa and to their major compounds rotundifolone, carvone, and carvacrol. Nearly all concentrations of oils and compounds showed amebicidal activity. The IC50 values for L. sidoides, L. gracilis L. alba, and L. pedunculosa were found to be 18.19, 10.08, 31.79, and 71.47 μg/mL, respectively. Rotundifolone, carvacrol, and carvone were determined as the major compounds showing IC50 of 18.98, 24.74, and 43.62 μg/mL, respectively. With the exception of oil from L. alba, the other oils evaluated showed low cytotoxicity in the NCI-H292 cell line. Given these results, the oils investigated here are promising sources of compounds for the development of complementary therapy against amoebic keratitis and granulomatous amoebic encephalitis and can also be incorporated into cleaning solutions to increase their amebicidal efficiency.
A new intraluminal amebicide (Quinfamide) was tested to assess its effectivity and tolerance for treatment of non-dysenteric intestinal amebiasis. The drug was administered to three groups of ten patients each, whom received 300, 600 and 1 200 mg. on a 24 hours schedule. Another group of ten patients received Teclozan as control drug. Diagnosis and results were judged by rectosigmoidoscopy before, 15 and 30 days after treatment. In addition, microscopic investigation of ameba was performed in freshly passed stools, before, and after 8, 15 and 30 days of treatment. Success after treatment with the three doses of Quinfamide was obtained in 89.2% of the cases. Side reactions were clinically non-significant. More experience is needed before the effectivity of the drug is stablished.
Lamb, David C.; Warrilow, Andrew G. S.; Rolley, Nicola J.; Parker, Josie E.; Nes, W. David; Smith, Stephen N; Kelly, Diane E.; Kelly, Steven L.
In this study, we investigate the amebicidal activities of the pharmaceutical triazole CYP51 inhibitors fluconazole, itraconazole, and voriconazole against Acanthamoeba castellanii and Acanthamoeba polyphaga and assess their potential as therapeutic agents against Acanthamoeba infections in humans. Amebicidal activities of the triazoles were assessed by in vitro minimum inhibition concentration (MIC) determinations using trophozoites of A. castellanii and A. polyphaga. In addition, triazole e...
Full Text Available 328.1474 D02480.gif Antiprotozoal, Amebicide [DS:H00360] Same as: C07637 ATC code: P01AC01 Anatomical Thera... Antiparasitics Agents against Amebiasis and other antiprotozoals Dichloroacetamide derivatives Diloxanide [
Guevara, L; Garcia Tsao, G; Uscanga, L F
Quinfamide, a luminal amebicide, is a dichloroacetyl quinolol used to treat chronic and subacute intestinal amebiasis. Several previous dose-ranging studies have indicated that quinfamide is effective in a total dose of 300, 600, or 1,200 mg. The present study was undertaken to determine the efficacy of 100- and 200-mg doses, each given three times daily. A cure rate of 100% was found at a dosage of 100 mg/8 hr and of 93.3% at 200 mg/8 hr. These results indicate that quinfamide is an effective luminal amebicide at the doses studied.
Full Text Available D07353 Drug Secnidazole (INN); Secnidal (TN) C7H11N3O3 185.08 185.1805 D07353.gif Antiprotozoa...l, amebicide; Antiprotozoal, trichomonacidal ATC code: P01AB07 Anatomical Therapeutic Chemical (A...nst Amebiasis and other antiprotozoals Nitroimidazole derivatives Secnidazole [ATC:P01AB07] D07353 Secnidazo
Iasmine A.B.S. Alves; Henrique M. Miranda; Luiz A. L. Soares; Karina P. Randau
The Simaroubaceae family includes 32 genera and more than 170 species of trees and brushes of pantropical distribution. The main distribution hot spots are located at tropical areas of America, extending to Africa, Madagascar and regions of Australia bathed by the Pacific. This family is characterized by the presence of quassinoids, secondary metabolites responsible of a wide spectrum of biological activities such as antitumor, antimalarial, antiviral, insecticide, feeding deterrent, amebicid...
Lamb, David C; Warrilow, Andrew G S; Rolley, Nicola J; Parker, Josie E; Nes, W David; Smith, Stephen N; Kelly, Diane E; Kelly, Steven L
In this study, we investigate the amebicidal activities of the pharmaceutical triazole CYP51 inhibitors fluconazole, itraconazole, and voriconazole against Acanthamoeba castellanii and Acanthamoeba polyphaga and assess their potential as therapeutic agents against Acanthamoeba infections in humans. Amebicidal activities of the triazoles were assessed by in vitro minimum inhibition concentration (MIC) determinations using trophozoites of A. castellanii and A. polyphaga. In addition, triazole effectiveness was assessed by ligand binding studies and inhibition of CYP51 activity of purified A. castellanii CYP51 (AcCYP51) that was heterologously expressed in Escherichia coli. Itraconazole and voriconazole bound tightly to AcCYP51 (dissociation constant [Kd] of 10 and 13 nM), whereas fluconazole bound weakly (Kd of 2,137 nM). Both itraconazole and voriconazole were confirmed to be strong inhibitors of AcCYP51 activity (50% inhibitory concentrations [IC50] of 0.23 and 0.39 μM), whereas inhibition by fluconazole was weak (IC50, 30 μM). However, itraconazole was 8- to 16-fold less effective (MIC, 16 mg/liter) at inhibiting A. polyphaga and A. castellanii cell proliferation than voriconazole (MIC, 1 to 2 mg/liter), while fluconazole did not inhibit Acanthamoeba cell division (MIC, >64 mg/liter) in vitro. Voriconazole was an effective inhibitor of trophozoite proliferation for A. castellanii and A. polyphaga; therefore, it should be evaluated in trials versus itraconazole for controlling Acanthamoeba infections. PMID:26014948
Araujo Rojas, F; Benavides Ledezma, M; Vega Martinez, C; Gomez Garza, R
Quinfamide, a dichloroacetyl quinolol synthesized and tested at Sterling Winthrop Research Institute, is a potent luminal amebicide with potential utility for a one-day treatment of chronic and subacute amebiasis caused by Entamoeba histolytica. Previous studies demonstrated that quinfamide is a safe and efficacious drug for adult patients when given as a one-day treatment regimen of 300 mg taken in tablet form at a dosage of 100 mg every eight hours. To test the drug in suspension form in pediatric patients, 46 children from newborn to 12 years old, assigned to groups according to age, were administered quinfamide in doses ranging from 50 to 300 mg/day as either single or divided doses. In all age groups quinfamide suspension, given as multiple doses in a single day, was shown to be highly effective in eliminating trophozoites from the stool. Cure rates ranged from 77.8% to 100%.
Iasmine A.B.S. Alves
Full Text Available The Simaroubaceae family includes 32 genera and more than 170 species of trees and brushes of pantropical distribution. The main distribution hot spots are located at tropical areas of America, extending to Africa, Madagascar and regions of Australia bathed by the Pacific. This family is characterized by the presence of quassinoids, secondary metabolites responsible of a wide spectrum of biological activities such as antitumor, antimalarial, antiviral, insecticide, feeding deterrent, amebicide, antiparasitic and herbicidal. Although the chemical and pharmacological potential of Simaroubaceae family as well as its participation in official compendia; such as British, German, French and Brazilian pharmacopoeias, and patent registration, many of its species have not been studied yet. In order to direct further investigation to approach detailed botanical, chemical and pharmacological aspects of the Simaroubaceae, the present work reviews the information regarding the main genera of the family up to 2013.
Full Text Available Although amebic liver abscess can be a cause of significant morbidity and mortality in all ages, there are few reports dealing with this entity in children. Twenty-four children with amebic liver abscess. Ages ranging between 8 weeks and 14.5 years were managed at the Tehran university hospital of children, Iran, between November 1987, and October 2001. The most frequency presentation was high-grade fever and right upper quadrant pain, associated with tender hepatomegaly, leukocytosis and an elevated erythrocyte sedimentation rate. The diagnosis was confirmed by elevated indirect hemagglutination titers and ultrasonograpy of the liver. Unlike the experience in adult patients, none of the patients had concomitant jaundice and significant derangement of liver enzymes. The abscesses were likely to be solitary (22 of 24 patients. There were 17 males and 7 females. Most patients (80% were between 8 weeks to 14.5 years of age. In five patients possible predisposing factors were tuberculosis, chickenpox, tetralogy of fallot and thalassemia major. All patients received metronidazole (50 mg/kg/day, followed by a therapeutic course of a luminal amebicide. There was no death despite a mean delay of 15 days before presentation to our hospital. In conclusion a high index of suspicion, early institution of metronidazole therapy and aspiration of abscesses with potential to rupture are believed to have contributed to the better outcome in these children when compared with results in previous reports.