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Sample records for amebicides

  1. [Amebicidal plants extracts].

    Science.gov (United States)

    Derda, Monika; Hadaś, Edward; Thiem, Barbara; Sułek, Anna

    2004-01-01

    The free-living amoebae from genus Acanthamoeba are the causative agents of granulomatous amebic encephalitis (GAE), a chronic progressive disease of the central nervous system; amebic keratitis (AK), a chronic eye infection; amebic pneumitis (AP), a chronic lung infection, and skin infection. Chemotherapy of Acanthamoeba infection is problematic. The majority of infections have been fatal. Only a few cases are reported to have been treated successfully with very highly toxic drugs. The therapy might be succeed, if the diagnosis and therapy is made at very early stage of infection. In our experiments we used the following plant extracts: Solidago virgaurea, Solidago graminifolia, Rubus chamaemorus, Pueraria lobata, and natural plants products as ellagic acid and puerarin. Those therapeutic agents and plants extracts have been tested in vitro for amebicidal or amebostatic activity against pathogenic Acanthamoeba spp. Our results showed that methanol extracts obtained from plants are active against axenic pathogenic Acanthamoeba sp. trophozoites in vitro at concentration below 0.1 mg/ml. Further studies are needed to investigate whether these extracts are also effective in vivo in animal model of infection with Acanthamoeba sp.

  2. Amebicidal activity of the essential oils of Lippia spp. (Verbenaceae) against Acanthamoeba polyphaga trophozoites.

    Science.gov (United States)

    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

    2016-02-01

    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.

  3. [Evaluation of the tolerance and efficiency of quinfamide, a new intraluminal amebicide, in man (one day treatment). Double blind study].

    Science.gov (United States)

    Guevara, L

    1980-01-01

    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.

  4. Chloroquine Phosphate Oral

    Science.gov (United States)

    Chloroquine phosphate is in a class of drugs called antimalarials and amebicides. It is used to prevent and treat ... Chloroquine phosphate comes as a tablet to take by mouth. For prevention of malaria in adults, one dose is ...

  5. Drug: D02480 [KEGG MEDICUS

    Lifescience Database Archive (English)

    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 [

  6. A study with quinfamide in the treatment of chronic amebiasis in adults.

    Science.gov (United States)

    Guevara, L; Garcia Tsao, G; Uscanga, L F

    1983-01-01

    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.

  7. Drug: D07353 [KEGG MEDICUS

    Lifescience Database Archive (English)

    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

  8. In vitro evaluation of the effectiveness of new water-stable cationic carbosilane dendrimers against Acanthamoeba castellanii UAH-T17c3 trophozoites.

    Science.gov (United States)

    Heredero-Bermejo, I; Copa-Patiño, J L; Soliveri, J; García-Gallego, S; Rasines, B; Gómez, R; de la Mata, F J; Pérez-Serrano, J

    2013-03-01

    Acanthamoeba is one of the most common free-living amoebas which is widespread in the environment and can infect humans, causing diseases such as keratitis and encephalitis. In this paper we examine for the first time the amebicidal activity of the family of cationic dendrimers nG-[Si{(CH(2))(3)N(+)(Me)(Et)(CH(2))(2)NMe(3) (+)}2I(-)]( x ) (where n denotes the generations: zero (n = 0, x = 1), first (n = 1, x = 4), and second (n = 2, x = 8); for simplicity, they were named as 0G-CNN2, 1G-CNN8, and 2G-CNN16, respectively) against Acanthamoeba castellanii UAH-T17c3 trophozoites. In order to test the amebicidal activity, we cultured the strain A. castellanii UAH-T17c3 in PYG-Bactocasitone medium and later, we treated it with different concentrations of these dendrimers and monitored the effects and damage by optical count, flow cytometry, and scanning electron microscopy. The results showed that all the nanosystems assayed had a strong amebicidal activity. The dendrimer 1G-CNN8 was the most effective against the amoeba. In the morphology of treated throphozoites of A. castellanii UAH-T17c3 analyzed by light and scanning electron microscopy techniques, morphological changes were evident in amoeba cells, such as loss of pseudopodia, ectoplasm increase, roundness, and cellular lysis. Furthermore, flow cytometry results showed alterations in cell granularity, which was dose-time dependent. In conclusion, this family of cationic carbosilane dendrimers has a strong amebicidal activity against the trophozoites of A. castellanii UAH-T17c3 in vitro. They could potentially become new agents significant to the development of new amebicidal compounds for prevention and therapy of Acanthamoeba infections.

  9. Bacteriocin-like substance from Bacillus amyloliquefaciens shows remarkable inhibition of Acanthamoeba polyphaga.

    Science.gov (United States)

    Benitez, Lisianne Brittes; Caumo, Karin; Brandelli, Adriano; Rott, Marilise Brittes

    2011-03-01

    The effectiveness of a bacteriocin-like substance (BLS) produced by Bacillus amyloliquefaciens was tested against Acanthamoeba polyphaga strains, and its cytotoxic potential on Vero cells was investigated. Amebicidal activity of the purified BLS was tested by plate bioassays with concentrations ranging from 12.5 to 6,400 AU mL(-1). Damage to A. pholyphaga cells was monitored using an inverted microscope and counted in a Fuchs-Rosenthal chamber after 24, 48, and 72 h. According to the results obtained, the BLS showed remarkable amebicidal and amebostatic effect on A. polyphaga and showed no cytotoxicity on the Vero cells. These results may have great relevance in the development of new acanthamoebicidal compounds.

  10. Azole Antifungal Agents To Treat the Human Pathogens Acanthamoeba castellanii and Acanthamoeba polyphaga through Inhibition of Sterol 14α-Demethylase (CYP51).

    Science.gov (United States)

    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

    2015-08-01

    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.

  11. Treatment of chronic amebiasis in pediatric patients with a suspension of quinfamide.

    Science.gov (United States)

    Araujo Rojas, F; Benavides Ledezma, M; Vega Martinez, C; Gomez Garza, R

    1983-01-01

    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%.

  12. Identification of natural inhibitors of Entamoeba histolytica cysteine synthase from microbial secondary metabolites

    Directory of Open Access Journals (Sweden)

    Mihoko eMori

    2015-09-01

    Full Text Available Amebiasis is a common worldwide diarrheal disease, caused by the protozoan parasite, Entamoeba histolytica. Metronidazole has been a drug of choice against amebiasis for decades despite its known side effects and low efficacy against asymptomatic cyst carriers. E. histolytica is also capable of surviving sub-therapeutic levels of metronidazole in vitro. Novel drugs with different mode of action are therefore urgently needed. The sulfur assimilatory de novo L-cysteine biosynthetic pathway is essential for various cellular activities, including the proliferation and anti-oxidative defense of E. histolytica. Since the pathway, consisting of two reactions catalyzed by serine acetyltransferase (SAT and cysteine synthase (CS, O-acetylserine sulfhydrylase, does not exist in humans, it is a rational drug target against amebiasis. To discover inhibitors against the CS of E. histolytica (EhCS, the compounds of Kitasato Natural Products Library were screened against two recombinant CS isozymes: EhCS1 and EhCS3. Nine compounds inhibited EhCS1 and EhCS3 with IC50 values of 0.31-490 μM. Of those, seven compounds share a naphthoquinone moiety, indicating the structural importance of the moiety for binding to the active site of EhCS1 and EhCS3.We further screened >9,000 microbial broths for CS inhibition and purified two compounds, xanthofulvin and exophillic acid from fungal broths. Xanthofulvin inhibited EhCS1 and EhCS3. Exophillic acid showed high selectivity against EhCS1, but exhibited no inhibition against EhCS3. In vitro anti-amebic activity of the 11 EhCS inhibitors was also examined. Deacetylkinamycin, deoxyfrenolicin, and nanaomycin A showed more potent amebicidal activity with IC50 values of 0.3-11 μM in the cysteine deprived conditions. The differential sensitivity of trophozoites against deacetylkinamycin in the presence or absence of L-cysteine in the medium and the IC50 values against EhCS suggest the amebicidal effect of deacetylkinamycin is

  13. Identification of natural inhibitors of Entamoeba histolytica cysteine synthase from microbial secondary metabolites.

    Science.gov (United States)

    Mori, Mihoko; Jeelani, Ghulam; Masuda, Yui; Sakai, Kazunari; Tsukui, Kumiko; Waluyo, Danang; Tarwadi; Watanabe, Yoshio; Nonaka, Kenichi; Matsumoto, Atsuko; Ōmura, Satoshi; Nozaki, Tomoyoshi; Shiomi, Kazuro

    2015-01-01

    Amebiasis is a common worldwide diarrheal disease, caused by the protozoan parasite, Entamoeba histolytica. Metronidazole has been a drug of choice against amebiasis for decades despite its known side effects and low efficacy against asymptomatic cyst carriers. E. histolytica is also capable of surviving sub-therapeutic levels of metronidazole in vitro. Novel drugs with different mode of action are therefore urgently needed. The sulfur assimilatory de novo L-cysteine biosynthetic pathway is essential for various cellular activities, including the proliferation and anti-oxidative defense of E. histolytica. Since the pathway, consisting of two reactions catalyzed by serine acetyltransferase (SAT) and cysteine synthase (CS, O-acetylserine sulfhydrylase), does not exist in humans, it is a rational drug target against amebiasis. To discover inhibitors against the CS of E. histolytica (EhCS), the compounds of Kitasato Natural Products Library were screened against two recombinant CS isozymes: EhCS1 and EhCS3. Nine compounds inhibited EhCS1 and EhCS3 with IC50 values of 0.31-490 μM. Of those, seven compounds share a naphthoquinone moiety, indicating the structural importance of the moiety for binding to the active site of EhCS1 and EhCS3. We further screened >9,000 microbial broths for CS inhibition and purified two compounds, xanthofulvin and exophillic acid from fungal broths. Xanthofulvin inhibited EhCS1 and EhCS3. Exophillic acid showed high selectivity against EhCS1, but exhibited no inhibition against EhCS3. In vitro anti-amebic activity of the 11 EhCS inhibitors was also examined. Deacetylkinamycin C and nanaomycin A showed more potent amebicidal activity with IC50 values of 18 and 0.8 μM, respectively, in the cysteine deprived conditions. The differential sensitivity of trophozoites against deacetylkinamycin C in the presence or absence of L-cysteine in the medium and the IC50 values against EhCS suggest the amebicidal effect of deacetylkinamycin C is due to CS

  14. In vitro efficacy of corifungin against Acanthamoeba castellanii trophozoites and cysts.

    Science.gov (United States)

    Debnath, Anjan; Tunac, Josefino B; Silva-Olivares, Angélica; Galindo-Gómez, Silvia; Shibayama, Mineko; McKerrow, James H

    2014-01-01

    Painful blinding keratitis and fatal granulomatous amebic encephalitis are caused by the free-living amebae Acanthamoeba spp. Several prescription eye medications are used to treat Acanthamoeba keratitis, but the infection can be difficult to control because of recurrence of infection. For the treatment of encephalitis, no single drug was found useful, and in spite of the use of a combination of multiple drugs, the mortality rate remains high. Therefore, efficient, novel drugs are urgently needed for the treatment of amebic keratitis and granulomatous amebic encephalitis. In this study, we identified corifungin, a water-soluble polyene macrolide, as amebicidal. In vitro, it was effective against both the trophozoites and the cysts. Transmission electron microscopy of Acanthamoeba castellanii incubated with corifungin showed the presence of swollen mitochondria, electron-dense granules, degeneration of cytoplasm architecture, and loss of nuclear chromatin structure. These changes were followed by lysis of amebae. Corifungin also induced the encystment process of A. castellanii. There were alterations in the cyst cell wall followed by lysis of the cysts. Corifungin is a promising therapeutic option for keratitis and granulomatous amebic encephalitis.

  15. Cytotoxic effect of acriflavine against clinical isolates of Acanthamoeba spp.

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    Polat, Zubeyda Akin; Karakus, Gulderen

    2013-02-01

    Acanthamoeba keratitis (AK) is a potentially devastating and sight-threatening infection of the cornea caused by the ubiquitous free-living amoebae, Acanthamoeba species. Its eradication is difficult because the amoebas encyst, making it highly resistant to anti-amoebic drugs. Acriflavine neutral (ACF) has been used for treatment of microbial infections for humans and fishes. The aim of our study was to evaluate the time-dependent cytotoxicities of ACF against Acanthamoeba spp. Trophozoites and cysts of three different strains (strain PAT06 Acanthamoeba castellanii, strain 2HH Acanthamoeba hatchetti, and strain 11DS A. hatchetti) of Acanthamoeba spp. were tested. All strains had been isolated from patients suffering from a severe AK. The effects of the ACF with the concentrations ranging from 15 to 500 mg mL(-1) on the cytotoxicity of Acanthamoeba strains were examined. ACF showed a time- and dose-dependent amebicidal action on the trophozoites and cysts. Pat06 (A. castellanii) was the most resistant, while strain 11DS (A. hatchetti) was the most sensitive. As a result, ACF could be concluded as a new agent for the treatment of Acanthamoeba infections. On the other hand, it still needs to be further evaluated by in vivo test systems to confirm the efficiency of its biological effect.

  16. [Investigation of the in vitro effects of Melissa officinalis L., Mentha x piperita L. and Ocimum basilicum L. (Lamiaceae) essential oils on the cysts and trophozoites of Acanthamoeba castellani].

    Science.gov (United States)

    Ergüden, Ceren; Özkoç, Soykan; Öztürk, Bintuğ; Bayram Delibaş, Songül

    2016-10-01

    Acanthamoeba species are free living amoeba found widely all over the world. They are responsible for Acanthamoeba keratitis (AK), an infection which is especially seen in contact lens users and after minor corneal traumas, that may lead blindness. At present, antifungals and antiseptics are used for the treatment of AK cases, however, some problems such as long treatment periods and the occurrence of side effects, resistance of cyst forms against drugs, emphasize the need for new drugs. There are some published studies that pointed out the effectiveness of plant extracts and essential oils on Acanthamoeba spp. The aim of this study was to investigate the in vitro effects of essential oils of Mentha x piperita L. (peppermint), Melissa officinalis L. (lemon balm) and Ocimum basilicum L. (basil) belonging to Lamiaceae family, on the cysts and trophozoites of Acanthamoeba castellanii. The strain used in our study, namely A. castellanii T4 genotype, is the most frequently isolated amoeba from environment and also the causative agent of AK and granulomatous amebic encephalitis. For the determination of amebicidal activity, essential oils obtained from Mentha x priperita L., Melissa officinalis L. and Ocimum basilicum L. by Neo-Clevenger type of distillation apparatus have been used. In vitro experiments were performed by using 96-well microplates. Cyst and trophozoite solutions were added on the essential oil dilutions to obtain the last concentrations of 40, 20, 10, 5, 2.5 and 1.25 µg/ml for the cysts, and 10, 5, 2.5, 1.25, 0.625 and 0.313 µg/ml for the trophozoites. After the incubation of microplates at 30oC for 1, 6, 24, 48 and 72 hours, the viability of parasitic forms were evaluated under the light microscope followed by staining trypan blue. It was found that, each essential oil showed amebicidal effect on A.castellani cysts and trophozoites dependent on dosage and time, when compared with the control group, The maximum lethal effect occured with Melissa

  17. Hepatic amebiasis

    Directory of Open Access Journals (Sweden)

    José Maria Salles

    2003-04-01

    Full Text Available Amebiasis can be considered the most aggressive disease of the human intestine, responsible in its invasive form for clinical syndromes, ranging from the classic dysentery of acute colitis to extra-intestinal disease, with emphasis on hepatic amebiasis, unsuitably named amebic liver abscess. Found worldwide, with a high incidence in India, tropical regions of Africa, Mexico and other areas of Central America, it has been frequently reported in Amazonia. The trophozoite reaches the liver through the portal system, provoking enzymatic focal necrosis of hepatocytes and multiple micro-abscesses that coalesce to develop a single lesion whose central cavity contains a homogeneous thick liquid, with typically reddish brown and yellow color similar to "anchovy paste". Right upper quadrant pain, fever and hepatomegaly are the predominant symptoms of hepatic amebiasis. Jaundice is reported in cases with multiple lesions or a very large abscess, and it affects the prognosis adversely. Besides chest radiography, ultrasonography and computerized tomography have brought remarkable contributions to the diagnosis of hepatic abscesses. The conclusive diagnosis is made however by the finding of Entamoeba histolytica trophozoites in the pus and by the detection of serum antibodies to the amoeba. During the evolution of hepatic amebiasis, in spite of the availability of highly effective drugs, some important complications may occur with regularity and are a result of local perforation with extension into the pleural and pericardium cavities, causing pulmonary abscesses and purulent pericarditis, respectively The ruptures into the abdominal cavity may lead to subphrenic abscesses and peritonitis. The treatment of hepatic amebiasis is made by medical therapy, with metronidazole as the initial drug, followed by a luminal amebicide. In patients with large abscesses, showing signs of imminent rupture, and especially those who do not respond to medical treatment, a

  18. Diminazene aceturate--An antiparasitic drug of antiquity: Advances in pharmacology & therapeutics.

    Science.gov (United States)

    da Silva Oliveira, George Laylson; de Freitas, Rivelilson Mendes

    2015-12-01

    Diminazene aceturate (C14H15N7.2C4H7NO3) is an aromatic diamidine that was developed more than six decades ago and has been marketed until today for the control of trypanosomiasis. In recent years, however, this trypanocidal compound has been extensively studied with respect to its therapeutic potential and has consequently attracted much interest for the development of further research. The objective of this study was to conduct a systematic review on diminazene aceturate regarding its pharmacological properties. In this way, databases were searched for articles (ScienceDirect, Scopus, PubMed, Web of Science and SciFinder) and patents (INPI, USPTO, WIPO, DPMA, SIPO, DERWENT, CIPO and EPO). For the development of this review, 115 articles and 22 patents were selected and analyzed. It was thus possible to highlight several researches that have investigated alternatives in order to improve success in the treatment of animal trypanosomiasis, by using new drugs in associations with diminazene aceturate, as well as looking for new pharmacological applications for this compound, such as leishmanicidal, amebicidal, anti-pneumocystis, anti-rheumatoid arthritis, antihypertensive agent, and mainly as an activator of angiotensin-converting enzyme 2. Another pharmacological property still little studied is the inhibition of acid-sensitive ion channels (ASIC1a, ASIC1b, ASIC2a and ASIC3), which are related to the development of various diseases. Collectively, these studies conducted by several research groups extend the use of diminazene aceturate beyond the antitrypanosomal activity and suggest promising new applications.