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Sample records for amebiasis

  1. 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

  2. [Amebiasis. Surgical treatment in 1989].

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    Sigler Morales, L; Mier y Díaz, J; Melgoza Ortiz, C; Blanco Benavides, R; Medina González, E

    1989-01-01

    Even when the number of patients with invasive amebiasis has decreased, the internist and surgeon must be alert in case that the patient requires an operation. Amebic liver abscess is treated medically; percutaneous evacuation is rarely used and surgical drainage is made when there is not response to medical treatment or there is high risk of abscess rupture. Operation is mandatory when the abscess has ruptured to the abdominal cavity or through the pericardial sac. In fulminant colitis it is necessary to resect the diseased portion of the colon without primary anastomoses. Amebic apendicitis is difficult to diagnosis before an operation. It may be suspected in cases of apendicitis if the cecal wall is inflammed. Colon ameboma requires medical treatment except if it is associated with necrosis or perforation. In a four year period (1985-1988) 294 patients with diagnosis of invasive amebiasis were admitted to three hospitals of the Instituto Mexicano del Seguro Social in Mexico City. 218 had hepatic abscess, 45 required surgical drainage with four deaths (9%) and four not operated patients died. In this series only four patients had their abscess drained percutaneously. 31 patients with amebic colitis were treated; three required colonic resection with one death. Ameboma was seen in five patients and there were 11 cases of amebic apendicitis. No deaths occurred in these last two groups.

  3. Accurate diagnosis is essential for amebiasis

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    @@ Amebiasis is one of the three most common causes of death from parasitic disease, and Entamoeba histolytica is the most widely distributed parasites in the world. Particularly, Entamoeba histolytica infection in the developing countries is a significant health problem in amebiasis-endemic areas with a significant impact on infant mortality[1]. In recent years a world wide increase in the number of patients with amebiasis has refocused attention on this important infection. On the other hand, improving the quality of parasitological methods and widespread use of accurate tecniques have improved our knowledge about the disease.

  4. Amebiasis

    Science.gov (United States)

    2011-06-01

    The nucleus is spherical and varies from 3.5µm to 6.0µm in diameter. The peripheral chromatin lining the inner surface of the nuclear membrane may be...arteriovenous malformation .5 Unusual manifestations of amebic colitis include acute necrotizing colitis, toxic megacolon, ameboma, perianal ul- ceration with...infection optimal therapy must be defined.58 Patients with Balamuthia infection may present with le- sions of the skin, sinus cavities, or middle ear . Skin

  5. Amebiasis

    Science.gov (United States)

    ... infection of the intestines caused by the parasite Entamoeba histolytica . Causes Entamoeba histolytica can live in the large intestine (colon) without ... have major health problems due to this disease. Entamoeba histolytica is spread through food or water contaminated with ...

  6. Human Amebiasis: Breaking the Paradigm?

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    Oswaldo Partida

    2010-03-01

    Full Text Available For over 30 years it has been established that the Entamoeba histolytica protozoan included two biologically and genetically different species, one with a pathogenic phenotype called E. histolytica and the other with a non-pathogenic phenotype called Entamoeba dispar. Both of these amoebae species can infect humans. E. histolytica has been considered as a potential pathogen that can cause serious damage to the large intestine (colitis, dysentery and other extraintestinal organs, mainly the liver (amebic liver abscess, whereas E. dispar is a species that interacts with humans in a commensal relationship, causing no symptoms or any tissue damage. This paradigm, however, should be reconsidered or re-evaluated. In the present work, we report the detection and genotyping of E. dispar sequences of DNA obtained from patients with amebic liver abscesses, including the genotyping of an isolate obtained from a Brazilian patient with a clinical diagnosis of intestinal amebiasis that was previously characterized as an E. dispar species. The genetic diversity and phylogenetic analysis performed by our group has shown the existence of several different genotypes of E. dispar that can be associated to, or be potentiality responsible for intestinal or liver tissue damage, similar to that observed with E. histolytica.

  7. Primary Pulmonary Amebiasis Complicated with Multicystic Empyema

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    Ali Zakaria

    2016-01-01

    Full Text Available Amebiasis is a parasitic infection caused by the protozoan Entamoeba histolytica. While most infections are asymptomatic, the disease could manifest clinically as amebic dysentery and/or extraintestinal invasion in the form of amebic liver abscess or other more rare manifestations such as pulmonary, cardiac, or brain involvement. Herein we are reporting a case of a 24-year-old male with history of Down syndrome who presented with severe right side pneumonia complicated with multicystic empyema resistant to regular medical therapy. Further investigation revealed a positive pleural fluid for E. histolytica cysts and trophozoites. The patient was diagnosed with primary pleuropulmonary amebiasis and he responded promptly to surgical drainage and metronidazole therapy. In patients from endemic areas all physicians should keep a high index of suspicion of amebiasis as a cause of pulmonary disease.

  8. Primary Pulmonary Amebiasis Complicated with Multicystic Empyema

    Science.gov (United States)

    Al-Share, Bayan; Al Asad, Khaled

    2016-01-01

    Amebiasis is a parasitic infection caused by the protozoan Entamoeba histolytica. While most infections are asymptomatic, the disease could manifest clinically as amebic dysentery and/or extraintestinal invasion in the form of amebic liver abscess or other more rare manifestations such as pulmonary, cardiac, or brain involvement. Herein we are reporting a case of a 24-year-old male with history of Down syndrome who presented with severe right side pneumonia complicated with multicystic empyema resistant to regular medical therapy. Further investigation revealed a positive pleural fluid for E. histolytica cysts and trophozoites. The patient was diagnosed with primary pleuropulmonary amebiasis and he responded promptly to surgical drainage and metronidazole therapy. In patients from endemic areas all physicians should keep a high index of suspicion of amebiasis as a cause of pulmonary disease. PMID:27478673

  9. Amebiasis: Epidemiología y Tratamiento

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    Alberto Albornoz Plata

    1986-08-01

    Full Text Available

    Introducción

    El concepto que se tenía hace varios años de “Enfermedades Tropicales” (se pensaba en un tipo de medicina exótica, como se llamaban en Europa, la malaria y amebiasis ha cambiado totalmente en la actualidad y específicamente para la amebiasis en el sentido de considerarla como enfermedad universal a la que puede ser susceptible cualquier ser humano que viva en cualquier sitio del mundo. Actualmente esta parasitosis cobra especial interés por los estudios inmunológicos, enzimáticos, epidemiológicos, metabólicos y terapéuticos que se desarrollan en centros muy especializados y se supone, con fundamento lógico, que no estará lejos el día en que se disponga de una vacuna eficaz contra esta enfermedad que ataca a muchas gentes, es causa de ausentismo al trabajo, incapacita por períodos largos a muchos pacientes por la complicación hepática y muchas veces es causa de mortalidad en los llamados casos de amebiasis invasora-fulminante.

    En este escrito solo se explicará lo referen te al aspecto epidemiológico y preventivo y, además, se hará énfasis para combatir ideas diagnósticas equivocadas con la entidad colon irritable.

    Al final se explicará el tratamiento actual de la amebiasis.

    Prevalencia y Susceptibilidad
    La amebiasis se considera como una enfermedad mundial, pero la mayor frecuencia es en aquellos lugares en donde las condiciones higiénicas ambientales son defectuosas, en especial lo referente al correcto suministro de agua potable, al buen tratamiento de las excretas y al control sanitario de los alimentos; por este motivo, en los países sub-desarrollados, o mejor subprivilegiados, y en las clases socio-económicas débiles, es donde más se encunetra esta enfermedad.

    Se ha calculado que en el mundo, el 20%de la población alberga la Endamoeba histolytica (l pero la gran mayoría no se consideran enfermos ya que son simplemente

  10. Entamoeba Encystation: New Targets to Prevent the Transmission of Amebiasis

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    Mi-ichi, Fumika; Yoshida, Hiroki; Hamano, Shinjiro

    2016-01-01

    Amebiasis is caused by Entamoeba histolytica infection and can produce a broad range of clinical signs, from asymptomatic cases to patients with obvious symptoms. The current epidemiological and clinical statuses of amebiasis make it a serious public health problem worldwide. The Entamoeba life cycle consists of the trophozoite, the causative agent for amebiasis, and the cyst, the form responsible for transmission. These two stages are connected by “encystation” and “excystation.” Hence, developing novel strategies to control encystation and excystation will potentially lead to new measures to block the transmission of amebiasis by interrupting the life cycle of the causative agent. Here, we highlight studies investigating encystation using inhibitory chemicals and categorize them based on the molecules inhibited. We also present a perspective on new strategies to prevent the transmission of amebiasis. PMID:27764256

  11. Impaired consciousness revealing a cerebral amebiasis in an immunocompetent adult

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    Hanane Ezzouine

    2012-01-01

    Full Text Available Amebiasis is a parasitic infection with manifestations, mainly digestives. It is rarely described extra-gastrointestinal locations including the brain. We report the case of a patient aged 42, made five months earlier for an appendectomy, and was admitted to the ICU after a convalescent stable uncomplicated. At admission, he was 12/15 in Glasgow and had a right hemiplegia. Brain CT revealed a discrete diffuse hypodensities perilesional edema. An abdominal ultrasound found an aspect for multiple hepatic abscesses. Abscess puncture was performed, which was not conclusive, and no seed could be identified. On Ultrasound, no cardiac abnormalities were found, and no endocarditis was present. And since the appearance macroscopic (chocolate-brown, amebic serology is performed and has been highly positive. The therapeutic management included an intubation and ventilation as well as a tri-antibiotic-based ceftriaxon, metronidazol and gentamycin. Confirmation of amebiasis required high doses of metronidazol for an extended period. The replay of the play was an appendectomy for an amebome. Evolution was favorable. Amebiasis can have extraintestinal locations, issues to think about including the cerebral forms.

  12. Extra-intestinal amebiasis: clinical presentation in a non-endemic setting

    DEFF Research Database (Denmark)

    Thorsen, S; Rønne-Rasmussen, J; Petersen, E;

    1993-01-01

    37/38 patients with reciprocal titers > or = 512 against Entamoeba histolytica in Denmark over a 5-year period were evaluated retrospectively in order to establish the clinical profile of extra-intestinal amebiasis in a non-endemic area. 24 of these had extra-intestinal amebiasis, all presenting 1...

  13. Does the eosinophil have a protective role in amebiasis?

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    López-Osuna Martha

    1997-01-01

    Full Text Available While normal human eosinophils are destroyed in vitro by virulent Entamoeba histolytica, notwhistanding the presence of antibodies and complement, activated eosinophils promptly destroy the parasite although dying also at the end of the process. To study the possible in vivo participation of eosinophils in invasive amebiasis, we compared the induction of experimental amebic abscess of the liver (AAL in gerbils (Meriones unguiculatus previously made eosinophilic through Toxocara canis antigen injection and in normal control gerbils. After intraportal inoculation of 10(5 ameba trophozoites (6 and 24 hr, the ratio of gerbils with AAL, as well as the number and size of the microabscesses was comparable in eosinophilic and control gerbils. However, at 96 hr the number and size of the microabscesses were significanly smaller (p<0.05 in eosinophilic gerbils. On the other hand the actuarial AAL survival curve up to 45 days post-amebic inoculation was signficantly (p<0.05 shifted to the right in controls. These results suggest that antigen-induced eosinophilia may exert a protective effect against AAL in gerbils.

  14. Prevalence of amebiasis in inflammatory bowel disease in Turkey

    Institute of Scientific and Technical Information of China (English)

    Sebnem Ustun; Hande Dagci; Umit Aksoy; Yuksel Guruz; Galip Ersoz

    2003-01-01

    AIM: To explore the prevalence of amebiasis in inflammatory bowel disease (IBD) in Turkey.METHODS: In this study, amoeba prevalence in 160 cases of IBD, 130 of ulcerative colitis and 30 of Crohn′s disease were investigated in fresh faeces by means of wet mount+Lugol′s iodine staining, modified formol ethyl acetate and trichrome staining methods and to compare the diagnostic accuracy of wet mount+Lugol′s iodine staining,modified formol ethyl acetate and trichrome staining methods in the diagnosis of Entamoeba histolytica (E. histolytica)/Entamoeba dispar (E. dispar).RESULTS: E. histolytica/E. dispar cysts and trophozoites were found in 14 (8.75 %) of a total of 160 cases, 13 (10.0 %)of the 130 patients with ulcerative colitis and 1 (3.3 %) of the 30 patients with Crohn′s disease. As for the 105 patients in the control group who had not any gastrointestinal complaints, 2 (1.90 %) patients were found to have E.histolytica/E. dispar cysts in their faeces. Parasite prevalence in the patient group was determined to be significantly higher than that in the control group (Fischer′s Exact Test, P<0.05).When the three methods of determining parasites were compared with one another, the most effective one was found to be trichrome staining method (Kruskal-Wallis Test, P<0.01).CONCLUSION: Consequently, amoeba infections in IBD cases have a greater prevalence compared to the normal population. The trichrome staining method is more effective for the detection of E. histolytica/E. dispar than the wet mount+Lugol′s iodine staining, modified formol ethyl acetate methods.

  15. Towards the establishment of a porcine model to study human amebiasis.

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    Fabienne Girard-Misguich

    Full Text Available BACKGROUND: Entamoeba histolytica is an important parasite of the human intestine. Its life cycle is monoxenous with two stages: (i the trophozoite, growing in the intestine and (ii the cyst corresponding to the dissemination stage. The trophozoite in the intestine can live as a commensal leading to asymptomatic infection or as a tissue invasive form producing mucosal ulcers and liver abscesses. There is no animal model mimicking the whole disease cycle. Most of the biological information on E. histolytica has been obtained from trophozoite adapted to axenic culture. The reproduction of intestinal amebiasis in an animal model is difficult while for liver amebiasis there are well-described rodent models. During this study, we worked on the assessment of pigs as a new potential model to study amebiasis. METHODOLOGY/PRINCIPAL FINDINGS: We first co-cultured trophozoites of E. histolytica with porcine colonic fragments and observed a disruption of the mucosal architecture. Then, we showed that outbred pigs can be used to reproduce some lesions associated with human amebiasis. A detailed analysis was performed using a washed closed-jejunal loops model. In loops inoculated with virulent amebas a severe acute ulcerative jejunitis was observed with large hemorrhagic lesions 14 days post-inoculation associated with the presence of the trophozoites in the depth of the mucosa in two out four animals. Furthermore, typical large sized hepatic abscesses were observed in the liver of one animal 7 days post-injection in the portal vein and the liver parenchyma. CONCLUSIONS: The pig model could help with simultaneously studying intestinal and extraintestinal lesion development.

  16. Towards the Establishment of a Porcine Model to Study Human Amebiasis

    Science.gov (United States)

    Girard-Misguich, Fabienne; Cognie, Juliette; Delgado-Ortega, Mario; Berthon, Patricia; Rossignol, Christelle; Larcher, Thibaut; Melo, Sandrine; Bruel, Timothée; Guibon, Roseline; Chérel, Yan; Sarradin, Pierre; Salmon, Henri; Guillén, Nancy; Meurens, François

    2011-01-01

    Background Entamoeba histolytica is an important parasite of the human intestine. Its life cycle is monoxenous with two stages: (i) the trophozoite, growing in the intestine and (ii) the cyst corresponding to the dissemination stage. The trophozoite in the intestine can live as a commensal leading to asymptomatic infection or as a tissue invasive form producing mucosal ulcers and liver abscesses. There is no animal model mimicking the whole disease cycle. Most of the biological information on E. histolytica has been obtained from trophozoite adapted to axenic culture. The reproduction of intestinal amebiasis in an animal model is difficult while for liver amebiasis there are well-described rodent models. During this study, we worked on the assessment of pigs as a new potential model to study amebiasis. Methodology/Principal Findings We first co-cultured trophozoites of E. histolytica with porcine colonic fragments and observed a disruption of the mucosal architecture. Then, we showed that outbred pigs can be used to reproduce some lesions associated with human amebiasis. A detailed analysis was performed using a washed closed-jejunal loops model. In loops inoculated with virulent amebas a severe acute ulcerative jejunitis was observed with large hemorrhagic lesions 14 days post-inoculation associated with the presence of the trophozoites in the depth of the mucosa in two out four animals. Furthermore, typical large sized hepatic abscesses were observed in the liver of one animal 7 days post-injection in the portal vein and the liver parenchyma. Conclusions The pig model could help with simultaneously studying intestinal and extraintestinal lesion development. PMID:22205970

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

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    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.

  18. [Amebiasis: implications of the recognition of Entamoeba dispar and the identification of Entamoeba moshkovskii in humans].

    Science.gov (United States)

    Chacín-Bonilla, Leonor

    2010-06-01

    The history of Entamoeba histolytica is very confuse and shows several wrong concepts about the parasite and its relationship with the host. The poor correlation between the prevalence of asymptomatic and symptomatic amebiasis originated the proposal of three explicative hypothesis, among them was the concept of Brumpt that E. histolytica comprised two morphologically identical species, E. dysenteriae and E. dispar. The application of modern molecular techniques irrefutably proved that E. histolytica was really a complex of two species, confirming the concept of Brumpt almost 7 decades later. Recent studies have identified in humans E. moshkovskii, morphologically indistinguishable from E. histolytica and E. dispar, a great genetic diversity within each of these species, and heterogeneity in virulence among E. histolytica strains. The redescription of E. dispar, and the recovery of E. moshkovskii from humans have had a major impact in our understanding of E. histolytica and amebiasis with important clinical and epidemiologic implications. This has led to the need of a reevaluation of the infection in terms of prevalence and morbidity in the global population and to study the geographic distribution, prevalence, and transmission pattern of E. histolytica strains in order to detect those with epidemiologic relevance and predict the risk of amebic disease in a population.

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

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    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%.

  20. Entamoeba moshkovskii perspectives of a new agent to be considered in the diagnosis of amebiasis.

    Science.gov (United States)

    Heredia, Rubén Darío; Fonseca, Jairo Andrés; López, Myriam Consuelo

    2012-09-01

    During the last decade Entamoeba moshkovskii has become relevant given its capacity to infect humans, especially when considering that it is morphologically indistinguishable from E. histolytica. For a long time, E. moshkovskii was considered as a free living amoeba, but in the last decade it has been demonstrated that E. moshkovskii can infect humans and can be found more frequently in regions where amebiasis shows high prevalence values, becoming a challenge to differentiate it from the E. histolytica/E. dispar complex. Recently there have been studies that raise the possibility that E. moshkovskii could be a pathogenic species, as there are reports in different countries that associated this infection with gastrointestinal symptoms even though others have described it as a non pathogenic species. For this reasons, both clinical and epidemiological studies are required.

  1. [Taeniasis, amebiasis and other intestinal parasitosis in school age children from Michoacan State, Mexico].

    Science.gov (United States)

    Lara-Aguilera, R; Aguilar-Bucio, M T; Martínez-Toledo, J L

    1990-03-01

    92.3% schoolchildren aged 6-13 years of a mexican rural village, suspected foci of Taenia solium cysticercosis were screened for intestinal parasites with the main purpose to know the infection rate by taeniasis. An stool sample was collected to schoolchildren of the village and 95.4% of a urban private school as comparative group. Laboratory examinations were performed with the most accurate technics, included microscopies with an ocular micrometer. The general parasitation rate was 4 times higher in the rural village, but the percentages of Taenia spp. infection were 0.6% both of them. Entamoeba histolytica was observed 1.8% and 7.2% in the city and rural village, respectively. All the cases with taeniasis passed T. saginata after treatment with niclosamide. Negative results were obtained with the same chemotherapy in a randomly selected group of 112 schoolchildren which previous stool examination was reported negative. Neither taeniasis were demonstrated in 94 adult persons. These data are suggestive of the great variability on the transmission rates of T. solium cysticercosis in endemic areas and illustrate the faced methodological problems to confirm the diagnosis of taeniasis. By other hand support the hypothesis that estimates of infection rates with E. histolytica have been overdiagnosed in the country. Taeniasis-cysticercosis; schoolchildren; Taenia saginata; amebiasis.

  2. Comparison of real-time PCR protocols for differential laboratory diagnosis of amebiasis.

    Science.gov (United States)

    Qvarnstrom, Yvonne; James, Cleve; Xayavong, Maniphet; Holloway, Brian P; Visvesvara, Govinda S; Sriram, Rama; da Silva, Alexandre J

    2005-11-01

    Specific identification of Entamoeba spp. in clinical specimens is an important confirmatory diagnostic step in the management of patients who may be infected with Entamoeba histolytica, the species that causes clinical amebiasis. Distinct real-time PCR protocols have recently been published for identification of E. histolytica and differentiation from the morphologically identical nonpathogenic Entamoeba dispar. In this study, we compared three E. histolytica real-time PCR techniques published by December 2004. The limits of detection and efficiency of each real-time PCR assay were determined using DNA extracted from stool samples spiked with serially diluted cultured E. histolytica trophozoites. The ability of each assay to correctly distinguish E. histolytica from E. dispar was evaluated with DNA extracted from patients' stools and liver aspirates submitted for confirmatory diagnosis. Real-time PCR allowed quantitative analysis of the spiked stool samples, but major differences in detection limits and assay performance were observed among the evaluated tests. These results illustrate the usefulness of comparative evaluations of diagnostic assays.

  3. [Comparison of quinfamide vs etofamide in the Mexican population with intestinal amebiasis].

    Science.gov (United States)

    Olaeta Elizalde, R; Pérez Huacuja, R; Nájera Ruano, S

    1996-01-01

    An open comparative, prospective and randomized study was carried out to evaluate the efficacy and safety of quinfamide and etofamide in the treatment of intestinal amebiasis. This study evaluate two populations: children (1-16 years) and adults (17-80 years). The drugs used were quinfamide at doses of 4.3 mg/kg b.i.d. in children, and 100 mg t.i.d. adults both for one day; and etofamide at doses of 200 mg t.i.d. in children and 500 mg b.i.d. in adults both for three days. A total of 110 patients were included, 54 in the quinfamide group and 56 in the etofamide group. No significant difference between groups in baseline demographics characteristics were observed. Global healing rate for quinfamide group was 87% and for etofamife group was 76.8% (p = 0.0696). This difference was similar considering both group of populations. It is concluded that the therapeutical response was better for the quinfamide group than for the etofamide group. Both drugs have the same safety profile.

  4. Prevention of intestinal amebiasis by vaccination with the Entamoeba histolytica Gal/GalNac lectin.

    Science.gov (United States)

    Houpt, Eric; Barroso, Lisa; Lockhart, Lauren; Wright, Rhonda; Cramer, Carole; Lyerly, David; Petri, William A

    2004-01-26

    Prevention of intestinal infection by Entamoeba histolytica would block both invasive disease and parasite transmission. The amebic Gal/GalNAc lectin mediates parasite adherence to the colonic surface and fecal anti-lectin IgA is associated with protection from intestinal reinfection in children. We tested if vaccination with the E. histolytica Gal/GalNAc lectin could prevent cecal infection in a C3H mouse model of amebic colitis. Two trials using native lectin purified from the parasite and two trials using a 64 kDa recombinant fragment ("LecA") were performed with a combined intranasal and intraperitoneal immunization regimen using cholera toxin and Freund's adjuvants, respectively. Two weeks after immunization mice were challenged intracecally with trophozoites, and 4-12 weeks after challenge mice were sacrificed for histopathologic evaluation of infection. Vaccination prevented intestinal infection with efficacies of 84 and 100% in the two native lectin trials and 91 and 34% in the two LecA trials. Mice with detectable pre-challenge fecal anti-lectin IgA responses were significantly more resistant to infection than mice without fecal anti-lectin IgA responses. These results show for the first time that immunization with the Gal/GalNAc lectin can prevent intestinal amebiasis in mice and suggest a protective role for fecal anti-lectin IgA in vivo.

  5. Modulation of innate immune response by the vagus nerve in experimental hepatic amebiasis in rats.

    Science.gov (United States)

    Martínez-Jaimes, Mercedes D; García-Lorenzana, Mario; Muñoz-Ortega, Martin H; Quintanar-Stephano, Andrés; Ávila-Blanco, Manuel E; García-Agueda, Carlos E; Ventura-Juárez, Javier

    2016-10-01

    The parasympathetic nervous system has a crucial role in immunomodulation of the vagus nerve, its structure provides a pathogen detection system, and a negative feedback to the immune system after the pathogenic agent has been eliminated. Amebiasis is a disease caused by the protozoan parasite Entamoeba histolytica, considered the third leading cause of death in the world. The rats are used as a natural resistance model to amoebic liver infection. The aim of this study is to analyze the interaction of Entamoeba histolytica with neutrophils, macrophages, and NK cells in livers of intact and vagotomized rats. Six groups were studied (n = 4): Intact (I), Intact + amoeba (IA), Sham (S), Sham + amoeba (SA), Vagotomized (V) and Vagotomized + amoeba (VA). Animals were sacrificed at 8 h post-inoculation of E. histolytica. Then, livers were obtained and fixed in 4% paraformaldehyde. Tissue liver slides were stained with H-E, PAS and Masson. The best development time for E. histolytica infection was at 8 h. Amoeba was identified with a monoclonal anti-220 kDa E. histolytica lectin. Neutrophils (N) were identified with rabbit anti-human neutrophil myeloperoxidase, macrophages (Mɸ) with anti-CD68 antibody and NK cells (NK) with anti-NK. Stomachs weight and liver glycogen were higher in V. Collagen increased in VA, whereas vascular and neutrophilic areas were decreased. There were fewer N, Mɸ, NK around the amoeba in the following order IA > SA > VA (p < 0.05 between IA and VA). In conclusion, these results suggest that the absence of parasympathetic innervation affects the participation of neutrophils, macrophages and NK cells in the innate immune response, apparently by parasympathetic inhibition on the cellular functions and probably for participation in sympathetic activity.

  6. A novel Entamoeba histolytica cysteine proteinase, EhCP4, is key for invasive amebiasis and a therapeutic target.

    Science.gov (United States)

    He, Chen; Nora, George P; Schneider, Eric L; Kerr, Iain D; Hansell, Elizabeth; Hirata, Ken; Gonzalez, David; Sajid, Mohammed; Boyd, Sarah E; Hruz, Petr; Cobo, Eduardo R; Le, Christine; Liu, Wei-Ting; Eckmann, Lars; Dorrestein, Pieter C; Houpt, Eric R; Brinen, Linda S; Craik, Charles S; Roush, William R; McKerrow, James; Reed, Sharon L

    2010-06-11

    Entamoeba histolytica cysteine proteinases (EhCPs) play a key role in disrupting the colonic epithelial barrier and the innate host immune response during invasion of E. histolytica, the protozoan cause of human amebiasis. EhCPs are encoded by 50 genes, of which ehcp4 (ehcp-a4) is the most up-regulated during invasion and colonization in a mouse cecal model of amebiasis. Up-regulation of ehcp4 in vivo correlated with our finding that co-culture of E. histolytica trophozoites with mucin-producing T84 cells increased ehcp4 expression up to 6-fold. We have expressed recombinant EhCP4, which was autocatalytically activated at acidic pH but had highest proteolytic activity at neutral pH. In contrast to the other amebic cysteine proteinases characterized so far, which have a preference for arginine in the P2 position, EhCP4 displayed a unique preference for valine and isoleucine at P2. This preference was confirmed by homology modeling, which revealed a shallow, hydrophobic S2 pocket. Endogenous EhCP4 localized to cytoplasmic vesicles, the nuclear region, and perinuclear endoplasmic reticulum (ER). Following co-culture with colonic cells, EhCP4 appeared in acidic vesicles and was released extracellularly. A specific vinyl sulfone inhibitor, WRR605, synthesized based on the substrate specificity of EhCP4, inhibited the recombinant enzyme in vitro and significantly reduced parasite burden and inflammation in the mouse cecal model. The unique expression pattern, localization, and biochemical properties of EhCP4 could be exploited as a potential target for drug design.

  7. Suburban amoebiasis. CT and US findings and percutaneous treatment of amoebic liver abscess; Amebiasi sub-urbana: aspetti diagnostici con tomografia computerizzata ed ecografia e trattamento percutaneo degli ascessi amebici del fegato

    Energy Technology Data Exchange (ETDEWEB)

    Salzano, A.; De Rosa, A. [Ospedale Loreto Mare, Naples (Italy). Servizio di Radiologia; Rossi, E.; Carbone, M.; Mondillo, F. [Naples Univ. II, Naples (Italy).Dipt. di Scienze Biomorfologiche e Funzionali, Servizio di Diagnostica per Immagini; Tuccillo, M. [Azienda Ospedaliera di Rilievo Nazionale A. Cardarelli, Naples (Italy). Servizio di Radiologia; Capuano, N. [Ospedale Loreto Mare, Naples (Italy). Div. di Chirurgia; Nunziata, A. [Naples Univ. II, Naples (Italy). Ist. di Radiologia

    2000-03-01

    The study reports ultrasonography and computerise tomography findings in 16 patients with amoebic abscesses, 12 of whom lived in a temperate peripheral area north-east of Naples (Italy). All patients have a clinical-diagnostic condition called sub-urban amoebiasis. The personal experience with the US guided therapeutic drainage of amoebic abscess with repeated cavity washing, which is important for positive parasitology. Combined US and CT assessment facilitated the diagnosis of amoebiasis and its differentiation from pyogenic abscess and hepatoma. [Italian] La colonizzazione epatica rappresenta la localizzazione piu' comune dell'amebiasi extraintestinale e gli ascessi epatici ne costituiscono la manifestazione piu' frequente sviluppandosi nel 3-9 % dei pazienti affetti da infezione parassitaria. Diversi studi confermano che la terapia medica dell'amebiasi risulta piu' efficace quando viene associato il drenaggio percutaneo degli ascessi epatici con piu' rapida guarigione clinica e risposta favorevole dell'organismo. Scopo del presente lavoro e' di descrivere gli aspetti ecografici e di tomografia computerizzata degli ascessi amebici in un gruppo di 16 pazienti, 12 dei quali residenti in zona temperata e periferica di una vasta area a nord-est di Napoli presentandosi con caratteristico e raro quadro clinico-diagnostico definito amebiasi sub-urbana. Si discute infine l'esperienza personale del drenaggio terapeutico sotto guida ecografica dell'ascesso con tecnica del lavaggio ripetuto dalla cavita', importante ai fini della positivita' dell'esame. L'associazione dei reperti tipici ecografici e TC ha consentito la diagnosi agevole dell'amebiasi differenziandola dall'ascesso piogenico e dall'epatoma.

  8. Estudio seroepidemiologico de la amibiasis en una comunidad del estado Zulia, Venezuela A seroepidemiological study of amebiasis in a community of Zulia State, Venezuela

    Directory of Open Access Journals (Sweden)

    Leonor Chacin-Bonilla

    1990-12-01

    Full Text Available Se realizó un estudio seroepidemiologico de amibiasis en una comunidad de bajas condiciones socioeconómicas del Municipio Mara, Estado Zulia, Venezuela. Se estudiaron 283 individuos cuyas edades fluctuaron de 2 a 53 años. Se obtuvieron muestras de sueros, las cuales se examinaron con la prueba de hemaglutinación indirecta de KESSEL et al., según una modificación de MILGRAM et al. Se utilizó antígeno amibiano obtenido de cultivos axénicos de la raza HK9 de E. histolytica. La tasa de seropositividad obtenida fué de 46.6%; la mayoría de los reactores tenía títulos bajos y no presentaba signos de amibiasis. El porcentaje de seropositividad aumentó con la edad. Los resultados sugieren una alta endemicidad de la infección en esta comunidad, ocurriendo la transmisión con mucha mayor frecuencia que la amibiasis invasiva.In the present evaluation, a community of low socioeconomical conditions from Zulia State, Venezuela, was analyzed for the prevalence of antibodies to E. histolytica. Two hundred and eighty three serum samples were collected and examined by the indirect hemagglutination test according to a microtiter modification of the KESSEL and LEWIS method, as used by MILGRAM et al. Antigen prepared from axenically-grown. E. histolytica strain HK9 in Diamond's medium was used. The seropositivity rate obtained was 46.6% and the frequency of positive cases was dependent on age. The antibody profiles obtained suggest a high endemicity for this parasitic infection in the area studied, with a much higher level of transmission than invasive amebiasis.

  9. The Clinical Study of Ulcerative Colitis Complicated with Intestinal Amebiasis%溃疡性结肠炎合并阿米巴肠病临床特点探讨

    Institute of Scientific and Technical Information of China (English)

    徐柳; 李胜保; 童强; 王小虎

    2012-01-01

    目的 探讨溃疡性结肠炎合并阿米巴肠病的临床特点.方法 回顾性分析2003~2010年共104例溃疡性结肠炎患者诊治资料,其中15例确诊合并阿米巴肠病(A组),单纯性溃疡性结肠炎患者89例(B组),统计各患者的腹泻次数、贫血程度、低白蛋白血症程度及结肠病变范围.结果 A、B组患者中腹泻>6次/d者分别为13例、40例,血红蛋白<90 g/L患者分别为8例、16例,血清蛋白<30 g/L患者分别为10例、23例,结肠病变范围超过1/2的患者分别为12例、31例,两组存在统计学差异;15例溃疡性结肠炎合并阿米巴肠病患者中7例为先确诊溃疡性结肠炎,后获得阿米巴感染并致病,其余8例患者无法判断两种疾病的发病先后顺序.所统计病例中溃疡性结肠炎并发阿米巴肠病发病率为14.4%(15/104),高于阿米巴肠病在普通人群中发病率(同地区平均为0.44%,最高2.43%).结论 溃疡性结肠炎合并阿米巴肠病病情较单纯性溃疡性结肠炎患者严重;溃疡性结肠炎患者较普通人群更容易获得溶组织内阿米巴感染并致病.%Objective To investigate the clinical characteristics of ulcerative colitis complicated with intestinal amebiasis. Methods There were 104 case of patients diagnosed as ulcerative colitis from 2003 to 2010,of which 15 cases were diagnosed complicated with intestinal amebiasis(group A) ,the other ulcerative colitis not complicated with intestinal amebiasis in 89 cases (greup B). Retrospective analysis the treatment process of patients and record the frequency of diarrhea, degree of anemia, low albumin levels and colonic lesions. Results In group A and B the number of patients with diarrhea more than 6 times everyday respectively for the 13 cases,40 cases, patients with hemoglobin <90 g/L were 8 cases,16 cases. Patients whih serum albumin <30 g/L were 10 cases,23 cases,the patients with colonic lesions over half of the colon were 12 cases,31 cases

  10. Entamoeba histolytica: fecal antigen capture immunoassay for the diagnosis of enteric amebiasis by a monoclonal antibody Entamoeba histolytica: imunodiagnóstico, através de captura de antígeno fecal em amebíase entérica por um anticorpo monoclonal

    Directory of Open Access Journals (Sweden)

    Haydeé Urdaneta

    1996-02-01

    Full Text Available Amebiasis continues to be of epidemiological importance in underdeveloped countries. Clinical diagnosis and epidemiological setting in a region are based on the fecal microscopic identification of cysts or trophozoites. This procedure requires well trained personnel, is laborious, of low sensitivity and frequently yields false-positives results. The present study was designed to develop an immuno-enzymatic fecal 96 kDa antigen capture test (COPROELISA-Eh more sensitive and specific than microscopic diagnosis of amebiasis. Triplicates of 177 stool samples processed by the formol-ether concentration method, were defined as positive or negative by three experienced microscopic observers. Another aliquot was submitted to the antigen capture test by a monoclonal antibody against a specific membrane antigen of pathogenic strains of Entamoeba histolytica. Optical densities were interpreted as positive when they exceeded the mean value of negative samples plus two standard deviations. COPROELISA-Eh showed a 94.4% sensitivity, 98.3% specificity, 96.2% positive predictive value and 97.6% negative predictive value for the detection of E. histolytica in feces. COPROELISA-Eh is more sensitive and specific than microscopic examination, does not require specially trained personnel and allows the simultaneous processing of a large number of samples.A amebíase mantém sua importância epidemiológica em países subdesenvolvidos onde sua prevalência a converteu na parasitose de maior morbidade e mortalidade após malaria e esquistosomose. Em regra, tanto o diagnóstico clínico como os levantamentos epidemiológicos assentam na identificação microscópica de cistos e/ou trofozoítos em extractos fecais. Este procedimento requer pessoal muito bem treinado, é laborioso, e frequentemente fornece resultados contraditórios. Para obviar estas dificuldades, no presente trabalho montamos uma técnica de diagnóstico imunoenzimático baseado na captura de um ant

  11. Amebic liver abscess

    Science.gov (United States)

    Hepatic amebiasis; Extraintestinal amebiasis; Abscess - amebic liver ... Amebic liver abscess is caused by Entamoeba histolytica. This parasite causes amebiasis , an intestinal infection that is also called ...

  12. Amebiasis del sistema nervioso central: reporte de seis casos en el Perú

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    Enrique Orrego-Puelles

    Full Text Available Se reportan seis casos de encefalitis amebiana admitidos en el Instituto Nacional de Enfermedades Neoplásicas entre los años 1994-2010 en Perú; estos casos ingresaron por sospecha clínica de tumor cerebral primario maligno y uno como sarcoma orbito-nasal. Todos los casos provenían de departamentos costeros; tres tenían menos de 24 años de edad y cuatro de sexo masculino. Los síntomas más frecuentes fueron cefalea y convulsiones. Tres casos presentaron más de una lesión cerebral. Se realizó biopsia por estereotaxia en tres pacientes y el diagnóstico anatomopatológico diferencial, en dos casos, fue glioma de alto y bajo grado. Se logró confirmar el diagnóstico mediante técnicas moleculares en muestras parafinadas en tres casos. Todos los pacientes fallecieron en menos de 15 días desde su ingreso al instituto. La encefalitis amebiana puede ser erradamente interpretada como una neoplasia cerebral, ocasionando retraso en el manejo del cuadro infeccioso.

  13. THE USE OF THE INDIRECT HEMAGGLUTINATION TEST FOR THE DIAGNOSIS OF EXTRA - INTESTINAL AMEBIASIS IN JAKARTA

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    Kiap Sahab

    2012-09-01

    Full Text Available Mikro indirek hemagglutinasi test dengan antigen axenik dari Entamoeba histolytica telah dipakai untuk mendapatkan zat2 anti amuba dalam sera dari 15 kasus abses hati yang pasti dan 4 kasus yang tidak pasti, 13 kasus disenteri amubawi akuta, 6 kasus colitis amur.awi chronis, satu asymptomatik carrier, 39 pasien yang menderita penyakit! lain dari 43 donor darah. Sera dari abses hati terdapat 100 per sen positif untuk zat anti amuba sedangkan sera dari orang2 dengan colitis amubawi chronis dan sera dari kasus disenteri amubawi akuta terdapat positif dalam urutan 50 dan 15 persen. Titer dari sera abses hati berkisar antara 1 : 128 dan 1 : 4096 dan titer dari sera amubiasis intestinalis yang positif adalah 1 : 128. Dari kedua kontrol grup tidak terdapat zat2 anti dengan titer lebih dari 1 : 64 (tabel 1 dan 2. Dari penyelidikan ini dapat diambil kesimpulan bahwa test indirek hemagglutinasi test dapat dipakai untuk occult invasive amubiasis bila metoda.2 yang lazim gagal menemukan parasit.

  14. Amebiasis presenting as acute appendicitis: Report of a case and review of Japanese literature

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    Daisuke Ito

    2014-01-01

    CONCLUSION: We report a case of acute amebic appendicitis in a 31-year-old woman and review the ages at presentation, causative factors, treatments, and outcomes of 11 cases reported in Japan between 1995 and 2013.

  15. [Epidemic of autochthonous hepatic and intestinal amebiasis in a place near Grenoble].

    Science.gov (United States)

    Ambroise-Thomas, P; Goullier, A; Grillot, R; Lascaud, D; Rivoire, L; Perrin, Y

    1975-01-01

    We had the opportunity of studying an epidemic of autochthonous amoebiasis occurring in the autumn of 1974 in a small town of 4000 inhabitants 30 km from Grenoble. Attention was originally attracted by the occurrence in this town of two cases of hepatic amoebiasis and one of intestinal amoebiasis identified by rectoscopy. Systematic investigations (coproctic examinations and serological tests for amoebiasis by indirect antibody fluorescence) were then carried out on everyone in the locality with digestive disorders which were possibly referable to amoebiasis, and on the other members of their families. A total number of 148 coproctic examinations were made and in two cases revealed the presence of vegetative forms of Entamoeba histolytica. In both cases the infestation provoked few symptoms (asthenia, vague abdominal discomfort, intermittent and apparently banal diarrhoea). On the other hand 20 out of 94 serological tests revealed positive results, 14 of which were equal to or greater than a titre of 1/100, a level at which all risks of non-specificity are virtually ruled out under our experimental conditions. Material reasons made it impossible to subject these cases to repeated faecal checks, but in two of them at least the rectoscopic appearances were very suggestive of subacute intestinal amoebiasis. Moreover, amoebic disease appears to be well confirmed by the results obtained among the patients as a whole by treatment with Metroinidazole. A variety of hypotheses on the origin of this epidemic have been put forward and then abandoned (market garden produce, receipt by certain families of exotic frut from overseas). In actual fact water seems to be the point of departure, for, although specimens of water taken at 7 different levels in the water supply system failed to reveal the presence of a single amoeba, bacteriological analyses during autumn 1974 showed signs of faecal contamination. The locality, which is situated at the foot of the Chartreuse massif, receives its water solely from springs but there is a holiday camp for the staff of an international airline situated above the main water catchment.

  16. Importancia de las prostaglandinas en la amibiasis hepática The importance of prostaglandins in hepatic amebiasis

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    Blanca Sánchez-Ramírez

    2002-06-01

    Full Text Available Las prostaglandinas son importantes mediadores inflamatorios, pero también desempeñan un papel importante como reguladoras de las funciones de los linfocitos y los macrófagos. La inoculación por vía intrahepática o intraportal de trofozoitos viables de Entamoeba histolytica en hámsteres se caracteriza por una rápida respuesta inflamatoria aguda, en la cual los trofozoitos amibianos se ven rodeados sucesivamente por leucocitos polimorfonucleares, linfocitos y macrófagos. La incapacidad de estas células para contrarrestar la invasión amibiana ha sido demostrada en varios estudios. La prostaglandina E2 (PGE2 tiene potentes efectos sobre las células de la respuesta inmune; su participación durante la formación del absceso hepático se reportó recientemente. En este artículo hacemos una revisión de los hallazgos de los últimos años en relación con el estudio de los mediadores bioquímicos de la inflamación durante la infección con E. histolytica, y su posible participación en el establecimiento de la respuesta inmune en el huésped.Prostaglandins are important mediators of inflammation; they also play a role in the regulation of both lymphocyte and macrophage functions. Hamster's liver lesions resulting from intraportal or intrahepatic inoculation of living Entamoeba histolytica trophozoites are characterized by an acute inflammatory response, where trophozoites are successively surrounded by polymorphonuclear leukocytes, lymphocytes, and macrophages. Incapability of these cells to counteract amebic invasion has been demonstrated in some studies. Prostaglandin E2 (PGE2 has potent effects on immune cells; its participation in amebic liver abscess has been reported recently. This paper presents a review of recent discoveries on biochemical mediators produced during inflammation due to Entamoeba histolytica infection, and their possible role in establishing the host's immune response.

  17. Entamoeba histolytica pleuropulmonary infection. Case report and review of the literature.

    Science.gov (United States)

    Chalhoub, Sanaa; Kanafani, Zeina

    2012-01-01

    Pleuropulmonary amebiasis is the 2nd most common extraintestinal site of amebiasis after liver abscess. We describe a man with pleuropulmonary amebiasis presenting with pulmonary consolidation and pleural effusion. In patients with pneumonia coming from endemic countries such as Lebanon, pleuropulmonary amebiasis should be considered in the setting of chocolate-colored sputum, negative respiratory cultures, and failure of antibacterial therapy.

  18. Invasive amebiasis and ameboma formation presenting as a rectal mass: An uncommon case of malignant masquerade at a western medical center

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A 54-year-old man presented with rectal pain and bleeding secondary to ulcerated, necrotic rectal and cecal masses that resembled colorectal carcinoma upon colonoscopy. These masses were later determined to be benign amebomas caused by invasive Entamoeba histolytica, which regressed completely with medical therapy. In Western countries, the occurrence of invasive protozoan infection with formation of amebomas is very rare and can mistakenly masquerade as a neoplasm. Not surprisingly, there have been very few cases reported of this clinical entity within the United States. Moreover, we report a patient that had an extremely rare occurrence of two synchronous lesions, one involving the rectum and the other situated in the cecum. We review the current literature on the pathogenesis of invasive E. Histolytica infection and ameboma formation, as well as management of this rare disease entity at a western medical center.

  19. Gene migration for re-emerging amebiasis in Iran's northwest-Iraq borders: a microevolutionary scale for reflecting epidemiological drift of Entamoeba histolytica metapopulations.

    Science.gov (United States)

    Mohammadzadeh, Asad; Spotin, Adel; Mahami-Oskouei, Mahmoud; Haghighi, Ali; Zebardast, Nozhat; Kohansal, Kobra

    2017-01-01

    In the microevolutionary scales of Entamoeba isolates, the gene migration shows how Entamoeba spp. has epidemiologically drifted among border countries. Five hundred fecal samples were taken from patients suffering gastrointestinal disorders, abdominal pain, and diarrhea at Saggez, northwest Iran located within the border Iraq country. Following parasitological techniques, DNA samples were extracted and amplified by polymerase chain reaction (PCR) of 18S rRNA region to identify Entamoeba infections. To distinguish the Entamoeba spp., a multiplex PCR was conducted. Amplicons were sequenced to reconfirm their heterogeneity traits and phylogenetic analysis. Additionally, Entamoeba histolytica sequences of Iraq were retrieved from GenBank database. The suspected isolates were diagnosed as E. histolytica (2.2 %), Entamoeba moshkovskii (1 %), and Entamoeba dispar (0.4 %). Mixed Entamoeba infections did not detect among isolates. A parsimonious network of the sequence haplotypes displayed star-like features in the overall isolates containing E.h1, E.d2, and E.m3 as the most common haplotypes. According to analysis of molecular variance (AMOVA) test, high partial value of haplotype diversity (0.700 to 0.800) of E. histolytica was shown the total genetic variability within populations while nucleotide diversity was low among Iranian and Iraqi metapopulations. Neutrality indices of the 18S rRNA were shown negative values in E. histolytica populations which indicating significant deviations from neutrality. A pairwise fixation index (F-statistics [Fst]) as a degree of gene flow had a low value for all populations (0.001) while the number of migrants was 2.48. The statistically Fst value indicates that E. histolytica isolates are not genetically differentiated among shared isolates of Iran and Iraq. Occurrence of E.h1 between two regional populations indicates that there is dawn of Entamoeba flow due to transfer of alleles from one population to another population through host mobility and ecological alterations. To evaluate the hypothetical evolutionary scenario, further study is required to analyze Entamoeba spp. in the neighboring Middle East countries.

  20. 凹甲陆龟溶组织内阿米巴原虫病的病理组织学观察%Patho-histological observation of Manouria impressa with Entamoeba histolytica amebiasis

    Institute of Scientific and Technical Information of China (English)

    牛李丽; 王强; 杨光友; 黄道超; 姜波; 赵波; 余星明; 邓家波; 陈维刚

    2006-01-01

    对患溶组织内阿米巴原虫病而死亡的凹甲陆龟进行了系统的病理组织学观察,该病的病变主要发生在消化道、肝、心脏、肾、脾等部位,尤以胃肠道和肝病变最为明显,表现为卡他性-坏死性胃肠炎和坏死性-肉芽肿性肝炎,胃肠黏膜出血、水肿、上皮细胞变性、坏死脱落,形成溃疡灶;肝细胞水泡变性,细胞核裂解,肝小叶内可见大小不等的结节性坏死灶,并伴有明显的炎症反应.

  1. Prevalence and importance of amebic infestation in patients with ulcerative colitis in two regions in Turkey.

    Science.gov (United States)

    Soylu, Aliye; Dolapcioglu, Can; Alis, Halil; Dolay, Kemal; Yasar, Nurgul; Boduroglu, Omer; Cildas, Aydin; Bolukbas, Fusun F; Bolukbas, Cengiz

    2009-06-01

    We investigated the prevalence of amebiasis in patients with ulcerative colitis residing in two geographical regions with different socioeconomic status and climatic conditions, and its effect on the age of onset, duration, localization, and activity of disease. Ninety patients from a high socioeconomic location (group I) and 28 cases from a low socioeconomic location (group II) were enrolled. Median age at disease onset was significantly higher in group I compared with in group II. Prevalence of amebiasis in group I was significantly lower than in group II. A considerably number of patients with amebiasis in group I had a history of travel to the cities with a lower socioeconomic level, mainly located in the east of Turkey. There was a strong relationship between presence of amebiasis and history of travel to eastern parts of Turkey among residents from the northwestern part of Turkey. Median age and age at time of diagnosis were significantly lower in patients with amebiasis compared with those without infection. In patients with mild disease activity, prevalence of amebiasis was significantly lower compared with those with moderate or severe disease activity. In conclusion, prevalence of amebiasis was markedly higher in the southeast compared to the northwest of Turkey. Travel to regions with low socioeconomic status may be considered a risk factor for amebiasis in patients with ulcerative colitis. Amebiasis enhances disease activity in ulcerative colitis.

  2. Drug: D07359 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available gents against amoebiasis and other protozoal diseases P01AX04 Phanquinone D07359 ...Phanquinone (INN) Antiinfectives [BR:br08307] Antiparasitics Agents against Amebiasis and other antiprotozoa

  3. 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 [

  4. Drug: D03985 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available TOZOAL DISEASES P01AX Other agents against amoebiasis and other protozoal disease...st Amebiasis and other antiprotozoals Others Emetine [ATC:P01AX02] D03985 Emetine hydrochloride (USP) CAS: 3

  5. Drug: D02548 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available PROTOZOAL DISEASES P01AX Other agents against amoebiasis and other protozoal diseases P01AX05 Mepacrine D02...548 Mepacrine dihydrochloride Antiinfectives [BR:br08307] Antiparasitics Agents against Amebiasis and other antiprotozoa

  6. Drug: D00828 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available T AMOEBIASIS AND OTHER PROTOZOAL DISEASES P01AX Other agents against amoebiasis and other protozoa...ntiparasitics Agents against Amebiasis and other antiprotozoals Others Dehydroemetine [ATC:P01AX09] D00828 D

  7. Drug: D07438 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available Other agents against amoebiasis and other protozoal diseases P01AX01 Chiniofon D...07438 Chiniofon (INN) Antiinfectives [BR:br08307] Antiparasitics Agents against Amebiasis and other antiprotozoa

  8. Drug: D07109 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D07109 Drug Broxyquinoline (INN); Starogyn (TN) C9H5Br2NO 300.8738 302.9501 D07109.gif Antiprotozoa... (INN) Antiinfectives [BR:br08307] Antiparasitics Agents against Amebiasis and other antiprotozoa

  9. Amoebicidal Activity of Essential Oil of Dysphania ambrosioides (L.) Mosyakin & Clemants in an Amoebic Liver Abscess Hamster Model

    OpenAIRE

    Manuel Enrique Ávila-Blanco; Martín Gerardo Rodríguez; José Luis Moreno Duque; Martin Muñoz-Ortega; Javier Ventura-Juárez

    2014-01-01

    Amebiasis is a parasitic disease that extends worldwide and is a public health problem in developing countries. Metronidazole is the drug recommended in the treatment of amebiasis, but its contralateral effects and lack of continuity of treatment induce low efficiency, coupled with the appearance of resistant amoebic strains. Therefore, the search of new compounds with amoebicidal activity is urgent and important. In this study, we evaluated the in vitro and in vivo antiamoebic activity of th...

  10. Diversity of clinical isolates of Entamoeba histolytica in Japan.

    Science.gov (United States)

    Nozaki, Tomoyoshi; Kobayashi, Seiki; Takeuchi, Tsutomu; Haghighi, Ali

    2006-02-01

    In Japan, amebiasis is domestically transmitted by two major populations: male homosexuals and mentally handicapped persons, which is remarkably different from most other developed countries where Entamoeba dispar infection is predominantly observed. Here we briefly summarize epidemiology of amebiasis in Japan. We also review our current understanding of the diversity of Entamoeba histolytica clinical isolates in Japan, based on polymorphic genetic markers, clinical representations, and in vivo virulence, using an animal model.

  11. Diagnóstico de amebíase intestinal utilizando métodos coproscópicos e imunológicos em amostra da população da área metropolitana de Belém, Pará, Brasil Diagnosis of intestinal amebiasis using coproscopic and immunological methods in a population sample in Greater Metropolitan Belém, Pará, Brazil

    Directory of Open Access Journals (Sweden)

    Marinete Marins Póvoa

    2000-09-01

    Full Text Available O artigo expõe a comparação de métodos de diagnóstico de Entamoeba histolytica em amostra da população de Belém do Pará. Foram analisadas amostras fecais de crianças e adultos (Grupo I, amostras fecais e soros de adultos (Grupo II e material fecal de crianças (Grupo III. Nos grupos I e III foram empregados os métodos direto com lugol (MD, Faust e cols. (MFF e ELISA (detecção de coproantígeno anti-GIAP de E. histolytica; no grupo II, MD, hematoxilina férrica (HF, MFF, ELISA e reação de imunofluorescência indireta (RIFI para detecção de anticorpos IgG. A positividade encontrada foi de 10,50%, empregando (MD + MFF e de 28,99% pelo ELISA. Não houve correlação entre positividade e grupo etário. No Grupo II (n = 87, a positividade encontrada foi de 4,59% pelos métodos coproscópicos (MD + MFF, 8,04% por HF, 4,59% pela RIFI e 21,83% pelo ELISA. O teste de ELISA foi o mais sensível para todos os grupos. Conclui-se que a RIFI ainda não é ferramenta útil para diagnóstico desta protozoose. O teste de ELISA, de fácil execução, foi feito em 1/3 do tempo usado para HF e RIFI, melhorando a qualidade do diagnóstico. Recomenda-se o ELISA como método de diagnóstico nos caso suspeitos de infecções com E. histolytica.We compare diagnostic methods for Entamoeba histolytica in fecal samples from the city of Belém, Pará, Brazil. We analyze stool samples from children and adults (Group I; stool and serum samples from adults (Group II; and stool samples from children (Group III. In groups I and III, we used direct examination with lugol (DM, Faust et al (FM, and ELISA (detection of E. histolytica anti-GIAP coproantigen and in group II, DM, iron hematoxylin staining (IHS, FM, ELISA, and the indirect immunofluorescence test (IFAT for detection of IgG antibodies. Positivity was 10.50% by DM plus FM and 28.99% by ELISA. There was no correlation between positivity and age group. In Group II (n = 87, the positive rate was 4.59% by DM plus FM, 8.04% by IHS, 4.59% by IFAT, and 21.83% by ELISA. The ELISA test was the most sensitive for all groups. IFAT alone is still not a useful tool for diagnosis of E. histolytica infection. The ELISA test is simple, performed in one-third of cases used for IHS and IFAT, and greatly improves quality of diagnosis. We recommend this as the method of choice for diagnosis of suspected E. histolytica infection.

  12. First case of amebic liver abscess 22 years after the first occurrence

    Directory of Open Access Journals (Sweden)

    Nespola Benoît

    2015-01-01

    Full Text Available A 72-year-old man consulted in November 2012 for abdominal pain in the right upper quadrant. The patient had a history of suspected hepatic amebiasis treated in Senegal in 1985 and has not traveled to endemic areas since 1990. Abdominal CT scan revealed a liver abscess. At first, no parasitological tests were performed and the patient was treated with broad-spectrum antibiotics. Only after failure of this therapy, serology and PCR performed after liver abscess puncture established the diagnosis of hepatic amebiasis. The patient was treated with metronidazole and tiliquinol-tilbroquinol. Amebic liver abscess is the most frequent extra-intestinal manifestation. Hepatic amebiasis 22 years after the last visit to an endemic area is exceptional and raises questions on the mechanisms of latency and recurrence of these intestinal protozoan parasites.

  13. Drug: D02125 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available 5.8625 D02125.gif Anti-amebic; Antimalarial; Suppressant [lupus erythematosus] [DS:H00360 H00361] ATC code: P01BA01 Indications: Mala...ria, Amebiasis Chloroquine should be administered with caution to patients having G

  14. Drug: D06238 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available OEBIASIS AND OTHER PROTOZOAL DISEASES P01AX Other agents against amoebiasis and other protozoal diseases P01... [ATC:P01AX07] D06238 Trimetrexate (USAN/INN) Antiinfectives [BR:br08307] Antiparasitics Agents against Amebiasis and other antiproto...zoals Others Trimetrexate [ATC:P01AX07] D06238 Trimetrex

  15. Drug: D03028 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D03028 Drug Azanidazole (USAN/INN) C10H10N6O2 246.0865 246.2254 D03028.gif Antiprotozoa...asitics Agents against Amebiasis and other antiprotozoals Nitroimidazole derivatives Azanidazole [ATC:G01AF1

  16. Drug: D08214 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D08214 Drug Metronidazole benzoate (USP); Elyzol (TN) C13H13N3O4 275.0906 275.26 D08214.gif Antiprotozoa...cs Agents against Amebiasis and other antiprotozoals Nitroimidazole derivatives Metronidazole [ATC:A01AB17 D

  17. Drug: D02486 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available X Other agents against amoebiasis and other protozoal diseases P01AX11 Nitazoxanide D02486 Nitazoxanide (USA...N/INN) USP drug classification [BR:br08302] Antiparasitics Antiprotozoals Nitazoxanide D02486 Nitazoxanide (...USAN/INN) Antiinfectives [BR:br08307] Antiparasitics Agents against Amebiasis and other antiprotozoa

  18. Drug: D01426 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available 0627 247.2715 D01426.gif Antiprotozoal [DS:H00812] Therapeutic category: 2529 6419 ATC code: J01XD02 P01AB02...P/INN) 6 Agents against pathologic organisms and parasites 64 Parasitics (systemic) 641 Antiprotozoans 6419 ...nidazole (JP16/USP/INN) Antiinfectives [BR:br08307] Antiparasitics Agents against Amebiasis and other antiprotozoa

  19. 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

  20. Drug: D07355 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D07355 Drug Etofamide (INN); Kitnos (TN) C19H20Cl2N2O5 426.0749 427.2785 D07355.gif Antiprotozoa...D07355 Etofamide (INN) Antiinfectives [BR:br08307] Antiparasitics Agents against Amebiasis and other antiprotozoa

  1. Drug: D07844 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D07844 Drug Diloxanide (INN) C9H9Cl2NO2 233.001 234.0793 D07844.gif Antiprotozoal, ...de (INN) Antiinfectives [BR:br08307] Antiparasitics Agents against Amebiasis and other antiprotozoals Dichlo

  2. Detection of Entamoeba histolytica by Recombinase Polymerase Amplification

    Science.gov (United States)

    Nair, Gayatri; Rebolledo, Mauricio; White, A. Clinton; Crannell, Zachary; Richards-Kortum, R. Rebecca; Pinilla, A. Elizabeth; Ramírez, Juan David; López, M. Consuelo; Castellanos-Gonzalez, Alejandro

    2015-01-01

    Amebiasis is an important cause of diarrheal disease worldwide and has been associated with childhood malnutrition. Traditional microscopy approaches are neither sensitive nor specific for Entamoeba histolytica. Antigen assays are more specific, but many cases are missed unless tested by molecular methods. Although polymerase chain reaction (PCR) is effective, the need for sophisticated, expensive equipment, infrastructure, and trained personnel limits its usefulness, especially in the resource-limited, endemic areas. Here, we report development of a recombinase polymerase amplification (RPA) method to detect E. histolytica specifically. Using visual detection by lateral flow (LF), the test was highly sensitive and specific and could be performed without additional equipment. The availability of this inexpensive, sensitive, and field-applicable diagnostic test could facilitate rapid diagnosis and treatment of amebiasis in endemic regions. PMID:26123960

  3. Amoebicidal Activity of Essential Oil of Dysphania ambrosioides (L.) Mosyakin & Clemants in an Amoebic Liver Abscess Hamster Model.

    Science.gov (United States)

    Avila-Blanco, Manuel Enrique; Rodríguez, Martín Gerardo; Moreno Duque, José Luis; Muñoz-Ortega, Martin; Ventura-Juárez, Javier

    2014-01-01

    Amebiasis is a parasitic disease that extends worldwide and is a public health problem in developing countries. Metronidazole is the drug recommended in the treatment of amebiasis, but its contralateral effects and lack of continuity of treatment induce low efficiency, coupled with the appearance of resistant amoebic strains. Therefore, the search of new compounds with amoebicidal activity is urgent and important. In this study, we evaluated the in vitro and in vivo antiamoebic activity of the essential oil Dysphania ambrosioides (L.) Mosyakin & Clemants. It exhibited an IC50 = 0.7 mg/mL against trophozoites. The oral administration of essential oil (8 mg/kg and 80 mg/kg) to hamster infected with Entamoeba histolytica reverted the infection. Ascaridole was identified as the main component of essential oil of D. ambrosioides. The identification of amoebicidal activity of Ascaridole gives support to the traditional use. Further studies with Ascaridole will be carried out to understand the mechanism involved.

  4. The future for vaccine development against Entamoeba histolytica.

    Science.gov (United States)

    Quach, Jeanie; St-Pierre, Joëlle; Chadee, Kris

    2014-01-01

    Entamoeba histolytica is the causative agent of amebiasis, one of the top three parasitic causes of mortality worldwide. In the majority of infected individuals, E. histolytica asymptomatically colonizes the large intestine, while in others, the parasite breaches the mucosal epithelial barrier to cause amebic colitis and can disseminate to soft organs to cause abscesses. Vaccinations using native and recombinant forms of the parasite Gal-lectin have been successful in protecting animals against intestinal amebiasis and amebic liver abscess. Protection against amebic liver abscesses has also been reported by targeting other E. histolytica components including the serine-rich protein and the 29-kDa-reductase antigen. To date, vaccines against the Gal-lectin hold the most promise but clinical trials will be required to validate its efficacy in humans. Here, we review the current strategies and future perspectives involved in the development of a vaccine against E. histolytica.

  5. Review: amebic liver abscess in children - the role of diagnostic imaging

    Energy Technology Data Exchange (ETDEWEB)

    Merten, D.F.; Kirks, D.R.

    1984-12-01

    Amebiasis, infection with the protozoan Entamoeba histolytica, affects at least 10% of the world's population, with an incidence exceeding 30% in tropical and subtropical regions. Amebic liver abscess (ALA) is the most common extraintestinal form of invasive amebiasis and is a serious life-threatening disease in children. Recent experience indicates the prognosis of ALA in childhood to be improved with early identification of abscesses and prompt institution of treatment. The authors incorporate experience with a case of ALA in infancy with a review of current literature (1974-1983) to delineate clinical and radiologic features of ALA in childhood and further define the role of hepatic imaging in the diagnosis and treatment.

  6. Discovery of Entamoeba histolytica hexokinase 1 inhibitors through homology modeling and virtual screening.

    Science.gov (United States)

    Saucedo-Mendiola, María Leticia; Salas-Pacheco, José Manuel; Nájera, Hugo; Rojo-Domínguez, Arturo; Yépez-Mulia, Lilián; Avitia-Domínguez, Claudia; Téllez-Valencia, Alfredo

    2014-06-01

    Entamoeba histolytica, the parasite which causes amebiasis is responsible for 110,000 deaths a year. Entamoeba histolytica depends on glycolysis to obtain ATP for cellular work. According to metabolic flux studies, hexokinase exerts the highest flux control of this metabolic pathway; therefore, it is an excellent target in the search of new antiamebic drugs. To this end, a tridimensional model of E. histolytica hexokinase 1 (EhHK1) was constructed and validated by homology modeling. After virtual screening of 14,400 small molecules, the 100 with the best docking scores were selected, purchased and assessed in their inhibitory capacity. The results showed that three molecules (compounds 2921, 11275 and 2755) inhibited EhHK1 with an I50 of 48, 91 and 96 µM, respectively. Thus, we found the first inhibitors of EhHK1 that can be used in the search of new chemotherapeutic agents against amebiasis.

  7. Structure of an ADP-ribosylation factor, ARF1, from Entamoeba histolytica bound to Mg(2+)-GDP.

    Science.gov (United States)

    Serbzhinskiy, Dmitry A; Clifton, Matthew C; Sankaran, Banumathi; Staker, Bart L; Edwards, Thomas E; Myler, Peter J

    2015-05-01

    Entamoeba histolytica is the etiological agent of amebiasis, a diarrheal disease which causes amoebic liver abscesses and amoebic colitis. Approximately 50 million people are infected worldwide with E. histolytica. With only 10% of infected people developing symptomatic amebiasis, there are still an estimated 100,000 deaths each year. Because of the emergence of resistant strains of the parasite, it is necessary to find a treatment which would be a proper response to this challenge. ADP-ribosylation factor (ARF) is a member of the ARF family of GTP-binding proteins. These proteins are ubiquitous in eukaryotic cells; they generally associate with cell membranes and regulate vesicular traffic and intracellular signalling. The crystal structure of ARF1 from E. histolytica has been determined bound to magnesium and GDP at 1.8 Å resolution. Comparison with other structures of eukaryotic ARF proteins shows a highly conserved structure and supports the interswitch toggle mechanism of communicating the conformational state to partner proteins.

  8. Construction and immunogenicity of a codon-optimized Entamoeba histolytica Gal-lectin-based DNA vaccine.

    Science.gov (United States)

    Gaucher, Denis; Chadee, Kris

    2002-09-10

    Invasive amebiasis caused by Entamoeba histolytica is the third leading parasitic cause of mortality, and there are no vaccines available to help control the disease. The galactose-adherence lectin (Gal-lectin) is the parasite's major molecule allowing it to adhere to colonic mucin for colonization and to target cells for tissue destruction. It is immunodominant and is regarded as the most promising candidate molecule to be included in a subunit vaccine against amebiasis. In this study, we are reporting the construction of a codon-optimized DNA vaccine encoding a portion of the Gal-lectin heavy subunit that includes the carbohydrate recognition domain (CRD), and its in vivo testing in mice. The vaccine stimulated a Th1-type Gal-lectin-specific cellular immune response as well as the development of serum antibodies that recognized a recombinant portion of the heavy subunit, and that inhibited the adherence of trophozoites to target cells in vitro.

  9. Rapid Diagnosis of Intestinal Parasitic Protozoa, with a Focus on Entamoeba histolytica

    Directory of Open Access Journals (Sweden)

    Anjana Singh

    2009-01-01

    Full Text Available Entamoeba histolytica is an invasive intestinal pathogenic parasitic protozoan that causes amebiasis. It must be distinguished from Entamoeba dispar and E. moshkovskii, nonpathogenic commensal parasites of the human gut lumen that are morphologically identical to E. histolytica. Detection of specific E. histolytica antigens in stools is a fast, sensitive technique that should be considered as the method of choice. Stool real-time PCR is a highly sensitive and specific technique but its high cost make it unsuitable for use in endemic areas where there are economic constraints. Serology is an important component of the diagnosis of intestinal and especially extraintestinal amebiasis as it is a sensitive test that complements the detection of the parasite antigens or DNA. Circulating Gal/GalNac lectin antigens can be detected in the serum of patients with untreated amoebic liver abscess. On the horizon are multiplex real-time PCR assays which permit the identification of multiple enteropathogens with high sensitivity and specificity.

  10. Detection of Entamoeba histolytica by Recombinase Polymerase Amplification.

    Science.gov (United States)

    Nair, Gayatri; Rebolledo, Mauricio; White, A Clinton; Crannell, Zachary; Richards-Kortum, R Rebecca; Pinilla, A Elizabeth; Ramírez, Juan David; López, M Consuelo; Castellanos-Gonzalez, Alejandro

    2015-09-01

    Amebiasis is an important cause of diarrheal disease worldwide and has been associated with childhood malnutrition. Traditional microscopy approaches are neither sensitive nor specific for Entamoeba histolytica. Antigen assays are more specific, but many cases are missed unless tested by molecular methods. Although polymerase chain reaction (PCR) is effective, the need for sophisticated, expensive equipment, infrastructure, and trained personnel limits its usefulness, especially in the resource-limited, endemic areas. Here, we report development of a recombinase polymerase amplification (RPA) method to detect E. histolytica specifically. Using visual detection by lateral flow (LF), the test was highly sensitive and specific and could be performed without additional equipment. The availability of this inexpensive, sensitive, and field-applicable diagnostic test could facilitate rapid diagnosis and treatment of amebiasis in endemic regions.

  11. Infectious diarrheas of infants and young children

    OpenAIRE

    Mata, Leonardo

    1985-01-01

    artículo -- Universidad de Costa Rica, Instituto de Investigaciones en Salud. 1985 Acute diarrhea' disease was once attributed to "indigestion." Although shigellosis, cholera, salmonellosis, giardiasis, and amebiasis have long been recognized as distinct clinical entities, it was not too long ago that many medical personnel had difficulty accepting the fact that most diarrheas are of infectious origin. The occurrence of diarrhea with the onset of weaning in many animal speci...

  12. A descriptive study of reportable gastrointestinal illnesses in Ontario, Canada, from 2007 to 2009

    OpenAIRE

    Vrbova Linda; Johnson Karen; Whitfield Yvonne; Middleton Dean

    2012-01-01

    Abstract Background Gastrointestinal illnesses (GI) continue to pose a substantial burden in terms of morbidity and economic impact in Canada. We describe the epidemiology of reportable GI in Ontario by characterizing the incidence of each reportable GI, as well as associated demographics, clinical outcomes, seasonality, risk settings, and likely sources of infection. Methods Reports on laboratory confirmed cases of amebiasis, botulism, campylobacteriosis, cryptosporidiosis, cyclosporiasis, g...

  13. Drug: D05017 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ics Agents against Amebiasis and other antiprotozoals Nitroimidazole derivatives Metronidazole [ATC:A01AB17 ...D05017 Drug Metronidazole phosphate (USAN) C6H10N3O6P 251.0307 251.1339 D05017.gif Antibacterial; Antiprotoz...oal ATC code: A01AB17 D06BX01 G01AF01 J01XD01 P01AB01 Anatomical Therapeutic Chemic

  14. Drug: D00236 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ASIS AND OTHER PROTOZOAL DISEASES P01AX Other agents against amoebiasis and other protozoa...asitics Agents against Amebiasis and other antiprotozoals Others Atovaquone [ATC:...l diseases P01AX06 Atovaquone D00236 Atovaquone (JAN/USP/INN) USP drug classification [BR:br08302] Antiparasitics Antiprotoz...oals Atovaquone D00236 Atovaquone (JAN/USP/INN) Antiinfectives [BR:br08307] Antipar

  15. Drug: D08179 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D08179 Drug Mepacrine (INN); Quinacrin C23H30ClN3O 399.2077 399.9568 D08179.gif Antiprotozoa...ZOAL DISEASES P01AX Other agents against amoebiasis and other protozoal diseases P01AX05 Mepacrine D08179 Me...pacrine (INN) Antiinfectives [BR:br08307] Antiparasitics Agents against Amebiasis and other antiprotozoals O

  16. US and CT findings of rectal amebian abscess

    Energy Technology Data Exchange (ETDEWEB)

    Guelek, B. [Dept. of Radiology, Adana Numune Teaching Hospital, Gar-Adana (Turkey); Oenel, S. [Dept. of General Surgery, Adana Numune Teaching Hospital, Gar-Adana (Turkey)

    1999-05-01

    An interesting case of rectal amebic abscess is presented. Ultrasound and CT images provided the diagnosis of a cystic intramural mass at the rectal wall of a young man, who complained of pelvic pain, constipation, and fever. His clinical history of amebiasis and the finding of trophozoids and cysts at the stool swap confirmed the diagnosis. Intravenous metronidazole therapy cured the disease and led to total disappearance of the mass, and clinical well-being. (orig.) With 4 figs., 6 refs.

  17. Tinidazol: un anaerobicida clásico con múltiples usos potenciales en la actualidad

    OpenAIRE

    Granizo Martínez, Juan José; Rodicio Rodicio, María Pía; Manso, Francisco J.; Giménez, María José

    2009-01-01

    El tinidazol es un 5-nitroimidazol activo in vitro frente a una amplia variedad de bacterias y protozoos anaerobios. Sus características farmacocinéticas (Cmáx 51µg/ml, t½ 12,5h) y su actividad in vitro frente a microorganismos anaerobios hacen de tinidazol un tratamiento eficaz para muchas infecciones causadas por estos microorganismos en dosis única o una vez al día. El tinidazol es tan eficaz como metronidazol en infecciones por T. vaginalis, giardiasis y amebiasis intestinal o hepática, a...

  18. Acute amebic appendicitis: Report of a rare case

    Directory of Open Access Journals (Sweden)

    Singh Naorem

    2010-10-01

    Full Text Available Acute appendicitis of amebic origin is considered a rare cause of acute appendicitis. We report a case of amebic appendicitis presenting with fever, severe pain in the right lower quadrant of the abdomen and rebound tenderness. Lab investigations revealed neutrophilic leukocytosis. The patient underwent appendectomy. Histopathological examination revealed numerous Entameba histolytica trophozoites in the mucosa of the appendix. Acute appendicitis of amebic origin does not appear frequently. Appendicular amebiasis can give the clinical features of acute appendicitis and should be treated accordingly.

  19. A Child with Intestinal Basidiobolomycosis

    Directory of Open Access Journals (Sweden)

    Reza Arjmand

    2012-06-01

    Full Text Available Fungal infections of the gastrointestinal tract are not common in children, especially in immunocompetent ones. In this case report we describe a child who was presented with abdominal pain and mass, bloody diarrhea and fever. He was treated for amebiasis, but due to treatment failure and deterioration of his condition, he underwent a laparatomy. Histologic examination of the excised bowel in the second look revealed Basidiobolomycosis, a fungus belonging to the order Entomophthorales. The signs, symptoms, treatment and diagnosis of the present case indicate that fungal infections must be considered not only in immunocompromised patients with abdominal pain and mass, but also in apparently immunocompetent ones.

  20. Drug: D00409 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ate (TN) C6H9N3O3 171.0644 171.154 D00409.gif Antiprotozoal [trichomonas] [DS:H00812] Same as: C07203 Therap...NN) 6 Agents against pathologic organisms and parasites 64 Parasitics (systemic) 641 Antiprotozoans 6419 Oth...le (JP16/USP/INN) Antiinfectives [BR:br08307] Antiparasitics Agents against Amebiasis and other antiprotoz...oals Nitroimidazole derivatives Metronidazole [ATC:A01AB17 D06BX01 G01AF01 J01XD01

  1. New drug target in protozoan parasites: the role of thioredoxin reductase.

    Science.gov (United States)

    Andrade, Rosa M; Reed, Sharon L

    2015-01-01

    Amebiasis causes approximately 70,000 deaths annually and is the third cause of death due to parasites worldwide. It is treated primarily with metronidazole, which has adverse side effects, is mutagenic and carcinogenic, and emergence of resistance is an increasing concern. Unfortunately, better therapeutic alternatives are lacking. Re-purposing of older FDA approved drugs is advantageous to drug discovery since safety and pharmacokinetic effects in humans are already known. In high throughput screening studies, we recently demonstrated that auranofin, a gold containing compound originally approved to treat rheumatoid arthritis, has activity against trophozoites of E. histolytica, the causative agent of amebiasis. Auranofin's anti-parasitic activity is attributed to its monovalent gold molecule that readily inhibits E. histolytica thioredoxin reductase. This anti-oxidant enzyme is the only thiol-dependent flavo-reductase present in E. histolytica. Auranofin has also shown promising activity against other protozoans of significant public health importance. Altogether, this evidence suggests that auranofin has the potential to become a broad spectrum alternative therapeutic agent for diseases with a large global burden.

  2. Development of loop-mediated isothermal amplification for rapid detection of Entamoeba histolytica

    Institute of Scientific and Technical Information of China (English)

    Windell L Rivera; Vanissa A Ong

    2013-01-01

    Objective: To develop a loop-mediated isothermal amplification (LAMP) assay for the detection of Entamoeba histolytica (E. histolytica), the causative agent of amebiasis. Methods: The LAMP primer set was designed from E. histolytica hemolysin gene HLY6. Genomic DNA of E. histolytica trophozoites strain HK9 was used to optimize the LAMP mixture and conditions. Amplification of DNA in the LAMP mixture was monitored through visual inspection for turbidity of the LAMP mix as well as addition of fluorescent dye. Results: Positive LAMP reactions turned turbid while negative ones remained clear. Upon addition of a fluorescent dye, all positive reactions turned green while the negative control remained orange under ambient light. After elecrophoresis in 1.5%agarose gels, a ladder of multiple bands of different sizes can be observed in positive samples while no bands were detected in the negative control. The sensitivity of the assay was found to be 5 parasites per reaction which corresponds to approximately 15.8 ng/μL DNA. The specificity of the assay was verified by the absence of amplified products when DNA from other gastrointestinal parasites such as the morphologically similar but non-pathogenic species, Entamoeba dispar, and other diarrhea-causing organisms such as Blastocystis hominis and Escherichia coli were used. Conclusions: The LAMP assay we have developed enables the detection of E. histolytica with rapidity and ease, therefore rendering it is suitable for laboratory and field diagnosis of amebiasis.

  3. [Sensibility of Entamoeba histolytica trophozoites to ivermectin].

    Science.gov (United States)

    González-Salazar, Francisco; Mata-Cárdenas, Benito D; Vargas-Villareal, Javier

    2009-01-01

    Amebiasis caused by Entamoeba histolytica is a problem of public world health. The most frequent clinical presentation are the dysentery and the amebic liver abscess. Fifty millions of cases and more than 100.000 deaths for this disease are reported annually worldwide. The life cycle of E. histolytica has two phases: trophozoite and cyst. Trophozoites are the causal agent of disease. The effective treatment for the amebiasis includes drugs with serious collateral effects. Ivermectin is a macrolid with activity against endoparasites and ectoparasites causing strongiloidosis, filariasis, oncocercosis, scabiasis and pediculosis. The use of ivermectin has been extended almost worldwide; it is recognized as a safe drug. The main objective of this study was to determine in vitro sensibility of trophozoites of E. histolytica was to the treatment with ivermectin. To determine the sensibility of the parasites to the drug, E. histolytica was cultivated in PEHPS medium. During its logarithmic growth phase the trophozoites were exposed to different concentrations of ivermectin. As controls other antiparasitic drugs were used. For each drug, serial dilutions were prepared, and mixed in culture tubes with parasites (2 x 104 cells/ml). They were incubated for 72 h and then the percentage of growth inhibition was calculated by Probit analysis. Ivermectin showed activity against trophozoites of E. histolytica. The 50% of growth inhibition of ivermectin was 6.40 mg/ml. This dose was higher than for other anti parasitic drugs. Its activity in vivo in animal models remains to be demonstrated.

  4. Magnetic removal of Entamoeba cysts from water using chitosan oligosaccharide-coated iron oxide nanoparticles.

    Science.gov (United States)

    Shukla, Sudeep; Arora, Vikas; Jadaun, Alka; Kumar, Jitender; Singh, Nishant; Jain, Vinod Kumar

    2015-01-01

    Amebiasis, a major health problem in developing countries, is the second most common cause of death due to parasitic infection. Amebiasis is usually transmitted by the ingestion of Entamoeba histolytica cysts through oral-fecal route. Herein, we report on the use of chitosan oligosaccharide-functionalized iron oxide nanoparticles for efficient capture and removal of pathogenic protozoan cysts under the influence of an external magnetic field. These nanoparticles were synthesized through a chemical synthesis process. The synthesized particles were characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and zeta potential analysis. The particles were found to be well dispersed and uniform in size. The capture and removal of pathogenic cysts were demonstrated by fluorescent microscopy, transmission electron microscopy, and scanning electron microscopy (SEM). Three-dimensional modeling of various biochemical components of cyst walls, and thereafter, flexible docking studies demonstrate the probable interaction mechanism of nanoparticles with various components of E. histolytica cyst walls. Results of the present study suggest that E. histolytica cysts can be efficiently captured and removed from contaminated aqueous systems through the application of synthesized nanoparticles.

  5. Tratamento da colite amebiana não disentérica com dose única de Teclozan

    Directory of Open Access Journals (Sweden)

    Donald Huggins

    1977-12-01

    Full Text Available Os autores trataram 30 pacientes portadores de colite amebiana não disentérica, de ambos os sexos (17 homens e 13 mulheres, com idades compreendidas entre 15 (dois casos a 55 anos (um doente, na Disciplina de Doenças Infecciosas. Parasitárias da Universidade Federal de Pernambuco. A posologia administrada foi de 1.500 mg em dose única e os resultados avaliados pelas técnicas de Hoffman, raspado da mucosa retaí, retossigmoidoscopia (em 16 enfermos e exame direto com ou sem coloração pelo lugol, foram de 80% (24 doentes de cura clínica e laboratorial. Nenhuma manifestação colateral foi relatada petos pacientas e concluem os autores que o Teclozan administrado em nova posologia, representa valioso subsídio no tratamento da amebíase intestinal.The authors report their experience with Teclozan in the treatment of 30 patients with chronic intestinal amebiasis, administering a new dosage 1.500 mgm in a single oral dosa. After a follow-up in the 7th, 14th, and 30th days after the treatment, the para sito togical cure rate obtained was 80% (24 cases and no side-effects were observed. The authors concluded that the drug (Teclozine is a very safe and effective agent in the treatment of amebiasis.

  6. Epidemiological features of intestinal infection with Entamoeba histolytica in Taiwan, 2002-2010.

    Science.gov (United States)

    Leung, Pak-On; Chen, Kou-Huang; Chen, Kwo-Liang; Tsai, Yu-Ting; Liu, Shyun-Yeu; Chen, Kow-Tong

    2014-01-01

    Amebiasis remains an important public health problem worldwide, and immigration and an increase in international travel have affected the incident cases of the disease. The purpose of this study was to assess the prevalence of Entamoeba histolytica in Taiwan between 2002 and 2010. We analyzed data from surveillance programs run by the Centers for Disease Control, Taiwan (Taiwan CDC), and only laboratory-confirmed cases were analyzed. In total, 1796 cases with E. histolytica infections were included in our analysis. Among them, 788 (44%) of the cases were imported, and 1008 (56%) were locally acquired. The average annual incidence rate of E. histolytica infections was 0.49 and 9.26 per 100,000 for local patients and immigrants/foreign workers from endemic countries, respectively. The annual incidence of E. histolytica infections among immigrants/foreign workers was significantly higher than among Taiwanese who had not traveled abroad (P histolytica-endemic areas (e.g., Southeast countries) had a higher risk acquiring an E. histolytica infection. This study emphasized that E. histolytica infection is an important intestinal infectious disease in Taiwan. The risk of infection with E. histolytica for travelers was higher for those with destinations in South and Southeast Asia. To control E. histolytica infections in Taiwan, a sensitive surveillance system needs to be established, and the amebiasis-screening program for immigrants/foreign workers from endemic countries should be enforced.

  7. New drug target in protozoan parasites: the role of thioredoxin reductase

    Directory of Open Access Journals (Sweden)

    Rosa M. Andrade

    2015-09-01

    Full Text Available Amebiasis causes approximately 70,000 deaths annually and is the third cause of death due to parasites worldwide. It is treated primarily with metronidazole, which has adverse side effects, is mutagenic and carcinogenic, and emergence of resistance is an increasing concern. Unfortunately, better therapeutic alternatives are lacking. Re-purposing of older FDA approved drugs is advantageous to drug discovery since safety and pharmacokinetic effects in humans are already known. In high throughput screening studies, we recently demonstrated that auranofin, a gold containing compound originally approved to treat rheumatoid arthritis, has activity against trophozoites of E. histolytica, the causative agent of amebiasis. Auranofin’s anti-parasitic activity is attributed to its monovalent gold molecule that readily inhibits E.histolytica thioredoxin reductase. This anti-oxidant enzyme is the only thiol-dependent flavo-reductase present in E.histolytica. Auranofin has also shown promising activity against other protozoans of significant public health importance. Altogether, this evidence suggests that auranofin has the potential to become a broad spectrum alternative therapeutic agent for diseases with a large global burden.

  8. Amoebicidal Activity of Essential Oil of Dysphania ambrosioides (L. Mosyakin & Clemants in an Amoebic Liver Abscess Hamster Model

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    Manuel Enrique Ávila-Blanco

    2014-01-01

    Full Text Available Amebiasis is a parasitic disease that extends worldwide and is a public health problem in developing countries. Metronidazole is the drug recommended in the treatment of amebiasis, but its contralateral effects and lack of continuity of treatment induce low efficiency, coupled with the appearance of resistant amoebic strains. Therefore, the search of new compounds with amoebicidal activity is urgent and important. In this study, we evaluated the in vitro and in vivo antiamoebic activity of the essential oil Dysphania ambrosioides (L. Mosyakin & Clemants. It exhibited an IC50 = 0.7 mg/mL against trophozoites. The oral administration of essential oil (8 mg/kg and 80 mg/kg to hamster infected with Entamoeba histolytica reverted the infection. Ascaridole was identified as the main component of essential oil of D. ambrosioides. The identification of amoebicidal activity of Ascaridole gives support to the traditional use. Further studies with Ascaridole will be carried out to understand the mechanism involved.

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

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    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

  10. 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

  11. An analysis of the association of gastroenteric lesions with chronic wasting syndrome of marmosets.

    Science.gov (United States)

    Chalifoux, L V; Bronson, R T; Escajadillo, A; McKenna, S

    1982-09-01

    Retrospective pathology data from necropsies of 162 marmosets, Saguinus oedipus, were studied to determine the nature of chronic wasting syndrome, a poorly defined entity associated with a high mortality rate in many marmoset colonies. Paraffin sections of the gastroenteric organs of 116 of these marmosets were re-examined in detail; lesions were identified, quantitated, and analyzed with a method of multiple chi-square testing for possible associations between findings. Five distinct disease entities were identified: prosthenorchosis, amebiasis, paramyxovirus disease, sepsis, and chronic colitis. Lesions of several of these often occurred in the same monkey, and all but the first were associated with cachexia. Lesions of chronic colitis were crypt abscesses, mononuclear and polymorphonuclear infiltration of the lamina propria, epithelial cell atypia, karyorrhexis, and lymphoid hyperplasia. The cause of chronic colitis was not identified, nor was any explanation found for weight loss and increased susceptibility to disease.

  12. PENYAKIT MENULAR SEKSUAL AKIBAT JAMUR, PROTOZOA, DAN PARASIT

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    Max Joseph Herman

    2012-09-01

    Full Text Available Berbagai penyakit akibat hubungan seksual (PHS selain yang disebabkan oleh bakteri, klamidia, virus, dan mikroplasma, juga mungkin disebabkan oleh jamur, protozoa dan parasit, antara lain kandidiasis, trikomoniasis, giardiasis, amebiasis, kudis, dan kutu pubis. Diagnosis PHS yang tepat dan pasti sangat penting karena mcmiliki konotasi sosial dan biasanya diperoleh melalui pemeriksaan mikroskopik, pembenihan bakteriologis atau virologis. Sedangkan penatalaksanaan PHS bergantung pada infeksi masing-masing individu, tetapi secara umum apabila PHS sendiri tidak/kurang serius seperti trikomoniasis atau ektoparasit maka tidak perlu pengamatan pasangan seksual meskipun harus diobati juga karena hampir pasti ia juga terinfeksi. Sebagian besar PHS lain demikian berat (dalam kasus gonore resistensi terhadap antibiotika merupakan masalah sehingga semua kontak seksual harus ditelusuri dan diobati, khususnya pada gonore, sifilis dan AIDS.

  13. Seroprevalence of Entamoeba histolytica infection in China.

    Science.gov (United States)

    Yang, Bin; Chen, Yingdan; Wu, Liang; Xu, Longqi; Tachibana, Hiroshi; Cheng, Xunjia

    2012-07-01

    The seroprevalence of Entamoeba histolytica infection in the residents of seven provinces in China was examined by using an enzyme-linked immunosorbent assay with a crude antigen and a recombinant surface antigen, C-Igl, of the parasites. A total of 1,312 serum samples were investigated. The positivity rates for these two antigens were 11.05% and 6.25%, respectively. There was no significant difference in the seropositivity to E. histolytica between men and women. We used a logistic regression model and maximal-likelihood methods to estimate the prevalence of E. histolytica infection from sequential serologic data. Seropositivity in Sichuan, Guizhou, and Sinkiang Provinces was higher than that in Beijing, Shanghai, and Qinghai Provinces. The present study provides an overview of seropositivity to E. histolytica infection in seven provinces in China and use the logistic regression model estimation method to achieve a more accurate measure of amebiasis prevalence.

  14. Amebic liver abscess with bacterial superinfection in a patient with no epidemiologic risk factors Absceso hepático amebiano sobreinfectado sin antecedentes epidemiológicos

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    P. Sánchez-Pobre

    2004-11-01

    Full Text Available The amebic liver abscess is uncommon in developed countries like Spain, but the incidence is increasing probably due to the migratory movements of the population. We report a case of an amebic abscess, initially unsuspected due to the absence of epidemiologic risk factors and the negative serology for amebiasis, in the early stages of the disease.El absceso hepático amebiano es infrecuente en países desarrollados, como lo es el caso de España, pero su incidencia está aumentando, posiblemente en relación con los movimientos migratorios de la población. Presentamos un caso de absceso hepático amebiano, no sospechado inicialmente, debido a la ausencia de antecedentes epidemiológicos y a la negatividad de las pruebas serológicas en las fases iniciales de enfermedad.

  15. Parasitic Colitis

    Science.gov (United States)

    Hechenbleikner, Elizabeth M.; McQuade, Jennifer A.

    2015-01-01

    Over one billion people worldwide harbor intestinal parasites. Parasitic intestinal infections have a predilection for developing countries due to overcrowding and poor sanitation but are also found in developed nations, such as the United States, particularly in immigrants or in the setting of sporadic outbreaks. Although the majority of people are asymptomatically colonized with parasites, the clinical presentation can range from mild abdominal discomfort or diarrhea to serious complications, such as perforation or bleeding. Protozoa and helminths (worms) are the two major classes of intestinal parasites. Protozoal intestinal infections include cryptosporidiosis, cystoisosporiasis, cyclosporiasis, balantidiasis, giardiasis, amebiasis, and Chagas disease, while helminth infections include ascariasis, trichuriasis, strongyloidiasis, enterobiasis, and schistosomiasis. Intestinal parasites are predominantly small intestine pathogens but the large intestine is also frequently involved. This article highlights important aspects of parasitic infections of the colon including epidemiology, transmission, symptoms, and diagnostic methods as well as appropriate medical and surgical treatment. PMID:26034403

  16. Microbiological and Pharmacological Evaluation of the Micropropagated Rubus liebmannii Medicinal Plant

    Directory of Open Access Journals (Sweden)

    Adelina Jiménez-Arellanes

    2012-01-01

    Full Text Available Rubus liebmannii is an endemic species from Mexico used in traditional medicine primarily to treat dysentery and cough. The in vitro activity against Giardia lamblia and Entamoeba histolytica that produces the ethanolic extract of the aerial parts of the plant led us to expand the pharmacological and phytochemical research of this species. Gastrointestinal disorders including amebiasis remain one of the health problems that need to be addressed and it is of interest to find alternatives that improve their treatment. Also, it is important to emphasize that R. liebmannii grows wild in the country and is not found in abundance; therefore, alternatives that avoid overexploitation of the natural resource are mandatory. Ongoing with the evaluation of the potentialities that R. liebmannii possesses for treating infectious gastrointestinal diseases, the aim of the present study was to evaluate the biological effects and the chemical composition of the micropropagated plant.

  17. Parasitic diseases in the abdomen: imaging findings.

    Science.gov (United States)

    Lim, Jae Hoon

    2008-01-01

    Parasitic diseases of the liver and biliary tract include echinococcosis, schistosomiasis, toxocariasis, clonorchiasis, and opisthorchiasis, affecting millions people in some endemic areas. Amebiasis and ascariasis are believed to be the most common bowel lumen indwelling parasitic diseases, affecting billions people worldwide, but sometimes these parasites migrate inadvertently to the liver and biliary tract, resulting in liver abscess or obstructive jaundice. Imaging findings of these parasitic diseases are fairly characteristic and easy to recognize if radiologists are aware of the findings, especially in endemic areas. Because of increased immigration and frequent travelling, some patients with "exotic" parasitic diseases may be encountered in non-endemic areas, and the diagnosis may be delayed or difficult, and it is often made only after operation. This feature section was designed to provide the detailed imaging features of common parasitic diseases affecting the abdominal organs and peritoneal cavity, based on pathology-image correlation.

  18. Parasitic diseases of the pleura.

    Science.gov (United States)

    Lal, Chitra; Huggins, John Terrill; Sahn, Steven A

    2013-05-01

    Parasitic infections are prevalent in certain parts of the world and may cause pleural involvement, which often goes unrecognized. Common parasites involving the pleura include Entamoeba histolytica, Echinococcus granulosus and Paragonimus westermani. Amebiasis can cause empyema with "anchovy sauce" pus, reactive pleural effusions and bronchopleural fistula with hydropneumothorax. Echinococcosis may result in pleural thickening, pneumothorax, secondary pleural hydatidosis and pleural effusions. Paragonimiasis may cause chylous and cholesterol pleural effusions, pleural thickening and pneumothorax. Less commonly, pulmonary eosinophilia, or Loeffler's syndrome, caused by Ascaris lumbricoides, Ancylostoma duodenale and Necator americanus and tropical pulmonary eosinophilia caused by Wuchereria bancrofti and Brugia malayi may involve the pleura. This article provides a comprehensive review of parasitic infections involving the pleura. A high index of suspicion in the appropriate clinical setting is required to facilitate prompt diagnosis and treatment of these diseases.

  19. [Tourism, imported parasitic diseases, and their prevention].

    Science.gov (United States)

    Tumol'skaia, N I; Zavoĭkin, V D; Mazmanian, M V; Plakhotnaia, G A; Kurbatova, I V; Zelia, O P; Gutova, V P

    2012-01-01

    The paper gives the results of observations of 1558 patients before and after tourist travels to tropical countries and 368 individuals visiting the north areas of the Russian Federation. Different conditions (malaria, amebiasis, leishmaniasis, intestinal and tissue helminthiasis, insect bites, venomous fish pricks, medusa burn, tick bites, etc.) were found in 402 persons. Prophylactic immunization included vaccination against hepatitis A and B viruses, meningitis, typhus, yellow fever, tick-borne encephalitis in more than 2500 patients (not including influenza vaccination in the epidemic season). The performed observations reinforce the statement that imported pathology is urgent to Russia and suggest that it is necessary to develop this section of medicine and to set up a network of health care facilities with a necessary therapeutic and diagnostic base to render skilled care to tourists. It is essential to improve medical staff training in travel medicine.

  20. Microbiological and Pharmacological Evaluation of the Micropropagated Rubus liebmannii Medicinal Plant

    Science.gov (United States)

    Jiménez-Arellanes, Adelina; Cornejo-Garrido, Jorge; Rojas-Bribiesca, Gabriela; Nicasio-Torres, María del Pilar; Said-Fernández, Salvador; Mata-Cárdenas, Benito David; Molina-Salinas, Gloria María; Tortoriello, Jaime; Meckes-Fischer, Mariana

    2012-01-01

    Rubus liebmannii is an endemic species from Mexico used in traditional medicine primarily to treat dysentery and cough. The in vitro activity against Giardia lamblia and Entamoeba histolytica that produces the ethanolic extract of the aerial parts of the plant led us to expand the pharmacological and phytochemical research of this species. Gastrointestinal disorders including amebiasis remain one of the health problems that need to be addressed and it is of interest to find alternatives that improve their treatment. Also, it is important to emphasize that R. liebmannii grows wild in the country and is not found in abundance; therefore, alternatives that avoid overexploitation of the natural resource are mandatory. Ongoing with the evaluation of the potentialities that R. liebmannii possesses for treating infectious gastrointestinal diseases, the aim of the present study was to evaluate the biological effects and the chemical composition of the micropropagated plant. PMID:22966243

  1. The medical care rendering to the infective patients in Afghanistan (1979 – 1989

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    K. S. Ivanov

    2009-01-01

    Full Text Available This article presents the author’s own experience of medical care rendered to the infective patients of the limited contingent of the Soviet troops in Afghanistan is generalized (1979 – 1989. According to factual evidence it is clear that during different periods of time, the percentage of the infective patients averages till 45,2 up to 67, 8% from the general number of the sanitary detachments. The most actual illnesses were typhoid fever, amebiasis, viral hepatitis, malaria and mixt-infections. In the article also covered the main steps of the formation and organization of the hospital base for the infective patients. Special attention is paid to the emergency aid implementation during so-called pre-admission period, realization of the medical grading and prevention of the intensive therapy in the hospitals.  

  2. Role of Eosinophils and Tumor Necrosis Factor Alpha in Interleukin-25-Mediated Protection from Amebic Colitis

    Science.gov (United States)

    Noor, Zannatun; Watanabe, Koji; Abhyankar, Mayuresh M.; Burgess, Stacey L.; Buonomo, Erica L.

    2017-01-01

    ABSTRACT The parasite Entamoeba histolytica is a cause of diarrhea in infants in low-income countries. Previously, it was shown that tumor necrosis factor alpha (TNF-α) production was associated with increased risk of E. histolytica diarrhea in children. Interleukin-25 (IL-25) is a cytokine that is produced by intestinal epithelial cells that has a role in maintenance of gut barrier function and inhibition of TNF-α production. IL-25 expression was decreased in humans and in the mouse model of amebic colitis. Repletion of IL-25 blocked E. histolytica infection and barrier disruption in mice, increased gut eosinophils, and suppressed colonic TNF-α. Depletion of eosinophils with anti-Siglec-F antibody prevented IL-25-mediated protection. In contrast, depletion of TNF-α resulted in resistance to amebic infection. We concluded that IL-25 provides protection from amebiasis, which is dependent upon intestinal eosinophils and suppression of TNF-α. PMID:28246365

  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. Regulation of adherence and virulence by the Entamoeba histolytica lectin cytoplasmic domain, which contains a beta2 integrin motif.

    Science.gov (United States)

    Vines, R R; Ramakrishnan, G; Rogers, J B; Lockhart, L A; Mann, B J; Petri, W A

    1998-08-01

    Killing of human cells by the parasite Entamoeba histolytica requires adherence via an amebic cell surface lectin. Lectin activity in the parasite is regulated by inside-out signaling. The lectin cytoplasmic domain has sequence identity with a region of the beta2 integrin cytoplasmic tail implicated in regulation of integrin-mediated adhesion. Intracellular expression of a fusion protein containing the cytoplasmic domain of the lectin has a dominant negative effect on extracellular lectin-mediated cell adherence. Mutation of the integrin-like sequence abrogates the dominant negative effect. Amebae expressing the dominant negative mutant are less virulent in an animal model of amebiasis. These results suggest that inside-out signaling via the lectin cytoplasmic domain may control the extracellular adhesive activity of the amebic lectin and provide in vivo demonstration of the lectin's role in virulence.

  5. Diagnostic imaging and interventional radiology of the amoebic liver abscess. Personal experience; Diagnostica per immagini e radiologia interventistica degli ascessi amebici del fegato: esperienza personale

    Energy Technology Data Exchange (ETDEWEB)

    De Rosa, A. [Ospedale S. Maria di Lorento Nuovo, NA (Italy). Servizio di Radiologia; Nunziata, A. [Neapel, Presidio Sanitario Intermedio (Italy). Area di Diagnostica per Immagini; Catalano, O.; Cusati, B.; Esposito, M.; Siani, A. [Ospedale di S. Maria delle Grazie, Pozzuoli, NA (Italy). Servizio di Radiologia

    1999-10-01

    The diagnostic imaging findings in hepatic amoebiasis and the capabilities of percutaneous drainage have already been described but some debate is open on both diagnosis and treatment. It is reported the experience with the ultrasound (US) and Computed Tomography (CT) studies of the hepatic amoebic abscess and its management. [Italian] I reperti con diagnostica per immagini nell'amebiasi epatica e le possibilita' del drenaggio percutaneo sono stati gia' illustrati; esistono tuttavia controversie sul piano sia diagnostico che terapeutico. Obiettivo di questo lavoro e' quello di riportare l'esperienza personale nella diagnostica con ecografia e tomografia computerizzata (TC) e nel trattamento degli ascessi amebici del fegato.

  6. FIXED DRUG ERUPTION DUE TO METRONIDAZOLE: REVIEW OF LITERATURE AND A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Wahlang JB

    2012-03-01

    Full Text Available Fixed drug eruption (FDE is common type of drug eruption seen in skin clinics. FDE usually occurs within hours of administration of the offending agent. Most commonly implicated are sulphonamides, salicylates, oxyphenbutazones, tetracycline, dapsone, chlordiazepoxide, barbiturates, phenolphthalein, morphine, codeine,quinine and derivatives, phenacetin, erythromycin, griseofulvin, mebendazole, meprobamate etc. We hereby report a case of fixed drug eruption on glans penis due to metronidazole, a nitroimidazole-derivative clinically indicated in trichomoniasis, amebiasis, giardiasis, anaerobic and mixed antibacterial infections. A patientadministered metronidazole IV developed erythematous superficial non-tender ulceration over the glans penis on the second day of treatment with Inj. Metronidazole. A provisional diagnosis of metronidazole induced fixed drug eruption was made, metronidazole inj. was stopped and the patient was managed with Tab. Prednisolone30mg/day tapered over 10 days and Fusidic acid+Betamethasone cream.

  7. Respiratory failure caused by intrathoracic amoebiasis

    Directory of Open Access Journals (Sweden)

    Toshinobu Yokoyama

    2010-03-01

    Full Text Available Toshinobu Yokoyama1, Masashi Hirokawa1, Yutaka Imamura2, Hisamichi Aizawa11Division of Respirology, Neurology and Rheumatology, Department of Internal Medicine, Kurume University, Japan; 2Department of Hematology, St. Mary’s Hospital, Kurume, JapanAbstract: A 41-year-old male was admitted to the hospital with symptoms of diarrhea, fever and rapidly progressive respiratory distress. A chest radiograph and computed tomography (CT of the chest and the abdomen showed a large amount of right pleural effusion and a large liver abscess. The patient was thus diagnosed to have amoebic colitis, amoebic liver abscess and amoebic empyema complicated with an HIV infection. The patient demonstrated agranulocytosis caused by the administration of trimethoprim-sulfamethoxazole. However, the administration of granulocyte colony-stimulating factor made it possible for the patient to successfully recover from agranulocytosis, and he thereafter demonstrated a good clinical course.Keywords: amebiasis, amoebic empyema, HIV, agranulocytosis, trimethoprim-sulfamethoxazole

  8. Proteomic Identification of Oxidized Proteins in Entamoeba histolytica by Resin-Assisted Capture: Insights into the Role of Arginase in Resistance to Oxidative Stress.

    Directory of Open Access Journals (Sweden)

    Preeti Shahi

    2016-01-01

    Full Text Available Entamoeba histolytica is an obligate protozoan parasite of humans, and amebiasis, an infectious disease which targets the intestine and/or liver, is the second most common cause of human death due to a protozoan after malaria. Although amebiasis is usually asymptomatic, E. histolytica has potent pathogenic potential. During host infection, the parasite is exposed to reactive oxygen species that are produced and released by cells of the innate immune system at the site of infection. The ability of the parasite to survive oxidative stress (OS is essential for a successful invasion of the host. Although the effects of OS on the regulation of gene expression in E. histolytica and the characterization of some proteins whose function in the parasite's defense against OS have been previously studied, our knowledge of oxidized proteins in E. histolytica is lacking. In order to fill this knowledge gap, we performed a large-scale identification and quantification of the oxidized proteins in oxidatively stressed E. histolytica trophozoites using resin-assisted capture coupled to mass spectrometry. We detected 154 oxidized proteins (OXs and the functions of some of these proteins were associated with antioxidant activity, maintaining the parasite's cytoskeleton, translation, catalysis, and transport. We also found that oxidation of the Gal/GalNAc impairs its function and contributes to the inhibition of E. histolytica adherence to host cells. We also provide evidence that arginase, an enzyme which converts L-arginine into L-ornithine and urea, is involved in the protection of the parasite against OS. Collectively, these results emphasize the importance of OS as a critical regulator of E. histolytica's functions and indicate a new role for arginase in E. histolytica's resistance to OS.

  9. Efficacy of saccharomyces boulardii with antibiotics in acute amoebiasis

    Institute of Scientific and Technical Information of China (English)

    Fariborz Mansour-Ghanaei; Najaf Dehbashi; Kamyar Yazdanparast; Afshin Shafaghi

    2003-01-01

    AIM: To compare the efficacy of antibiotics therapy alone with antibiotics and saccharomyces boulardii in treatment of acute amebiasis.METHODS: In a double blind, random clinical trial on patients with acute intestinal amoebiasis, 57 adult patients with acute amoebiasis, diagnosed with clinical manifestations (acute mucous bloody diarrhea) and amebic trophozoites engulfing RBCs found in stool were enrolled in the study.Regimen 1 induded metronidazole (750 mg Tid) and iodoquinol (630 mg Tid) for 10 days. Regimen 2 contained capsules of lyophilized saccharomyces boulardii (250 mg Tid) orally in addition to regimen 1. Patients were re-examined at two and four weeks after the treatment, and stool examination was performed at the end of week 4. Student′s t-test, χ2and McNemar′s tests were used for statistical analysis.RESULTS: Three patients refused to participate. The other 54 patients were randomized to receive either regimen 1 or regimen 2 (Groups 1 and 2 respectively, each with 27patients). The two groups were similar regarding their age,sex and clinical manifestations. In Group 1, diarrhea lasted 48.0±18.5 hours and in Group 2,12.0±3.7 hours (P<0.0001).In Group 1, the durations of fever and abdominal pain were 24.0±8.8 and 24.0±7.3 hours and in Group 2 they were 12.0±5.3 and 12.0±3.2 hours, respectively (P<0.001).Duration of headache was similar in both groups. At week 4, amebic cysts were detected in 5 cases (18.5 %) of Group 1 but in none of the Group 2 (P<0.02).CONCLUSION: Adding saccharomyces boulardii to antibiotics in the treatment of acute amebiasis seems to decrease the duration of clinical symptoms and cyst passage.

  10. Use of recombinant Entamoeba histolytica cysteine proteinase 1 to identify a potent inhibitor of amebic invasion in a human colonic model.

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    Meléndez-López, Samuel G; Herdman, Scott; Hirata, Ken; Choi, Min-Ho; Choe, Youngchool; Craik, Charles; Caffrey, Conor R; Hansell, Elisabeth; Chávez-Munguía, Bibiana; Chen, Yen Ting; Roush, William R; McKerrow, James; Eckmann, Lars; Guo, Jianhua; Stanley, Samuel L; Reed, Sharon L

    2007-07-01

    Cysteine proteinases are key virulence factors of the protozoan parasite Entamoeba histolytica. We have shown that cysteine proteinases play a central role in tissue invasion and disruption of host defenses by digesting components of the extracellular matrix, immunoglobulins, complement, and cytokines. Analysis of the E. histolytica genome project has revealed more than 40 genes encoding cysteine proteinases. We have focused on E. histolytica cysteine proteinase 1 (EhCP1) because it is one of two cysteine proteinases unique to invasive E. histolytica and is highly expressed and released. Recombinant EhCP1 was expressed in Escherichia coli and refolded to an active enzyme with a pH optimum of 6.0. We used positional-scanning synthetic tetrapeptide combinatorial libraries to map the specificity of the P1 to P4 subsites of the active site cleft. Arginine was strongly preferred at P2, an unusual specificity among clan CA proteinases. A new vinyl sulfone inhibitor, WRR483, was synthesized based on this specificity to target EhCP1. Recombinant EhCP1 cleaved key components of the host immune system, C3, immunoglobulin G, and pro-interleukin-18, in a time- and dose-dependent manner. EhCP1 localized to large cytoplasmic vesicles, distinct from the sites of other proteinases. To gain insight into the role of secreted cysteine proteinases in amebic invasion, we tested the effect of the vinyl sulfone cysteine proteinase inhibitors K11777 and WRR483 on invasion of human colonic xenografts. The resultant dramatic inhibition of invasion by both inhibitors in this human colonic model of amebiasis strongly suggests a significant role of secreted amebic proteinases, such as EhCP1, in the pathogenesis of amebiasis.

  11. Proteomic Identification of Oxidized Proteins in Entamoeba histolytica by Resin-Assisted Capture: Insights into the Role of Arginase in Resistance to Oxidative Stress.

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    Shahi, Preeti; Trebicz-Geffen, Meirav; Nagaraja, Shruti; Alterzon-Baumel, Sharon; Hertz, Rivka; Methling, Karen; Lalk, Michael; Ankri, Serge

    2016-01-01

    Entamoeba histolytica is an obligate protozoan parasite of humans, and amebiasis, an infectious disease which targets the intestine and/or liver, is the second most common cause of human death due to a protozoan after malaria. Although amebiasis is usually asymptomatic, E. histolytica has potent pathogenic potential. During host infection, the parasite is exposed to reactive oxygen species that are produced and released by cells of the innate immune system at the site of infection. The ability of the parasite to survive oxidative stress (OS) is essential for a successful invasion of the host. Although the effects of OS on the regulation of gene expression in E. histolytica and the characterization of some proteins whose function in the parasite's defense against OS have been previously studied, our knowledge of oxidized proteins in E. histolytica is lacking. In order to fill this knowledge gap, we performed a large-scale identification and quantification of the oxidized proteins in oxidatively stressed E. histolytica trophozoites using resin-assisted capture coupled to mass spectrometry. We detected 154 oxidized proteins (OXs) and the functions of some of these proteins were associated with antioxidant activity, maintaining the parasite's cytoskeleton, translation, catalysis, and transport. We also found that oxidation of the Gal/GalNAc impairs its function and contributes to the inhibition of E. histolytica adherence to host cells. We also provide evidence that arginase, an enzyme which converts L-arginine into L-ornithine and urea, is involved in the protection of the parasite against OS. Collectively, these results emphasize the importance of OS as a critical regulator of E. histolytica's functions and indicate a new role for arginase in E. histolytica's resistance to OS.

  12. The NLRP3 Inflammasome Is a Pathogen Sensor for Invasive Entamoeba histolytica via Activation of α5β1 Integrin at the Macrophage-Amebae Intercellular Junction.

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    Leanne Mortimer

    2015-05-01

    Full Text Available Entamoeba histolytica (Eh is an extracellular protozoan parasite of humans that invades the colon to cause life-threatening intestinal and extra-intestinal amebiasis. Colonized Eh is asymptomatic, however, when trophozoites adhere to host cells there is a considerable inflammatory response that is critical in the pathogenesis of amebiasis. The host and/or parasite factors that trigger the inflammatory response to invading Eh are not well understood. We recently identified that Eh adherence to macrophages induces inflammasome activation and in the present study we sought to determine the molecular events upon contact that coordinates this response. Here we report that Eh contact-dependent activation of α5β1 integrin is critical for activation of the NLRP3 inflammasome. Eh-macrophage contact triggered recruitment of α5β1 integrin and NLRP3 into the intercellular junction, where α5β1 integrin underwent activation by an integrin-binding cysteine protease on the parasite surface, termed EhCP5. As a result of its activation, α5β1 integrin induced ATP release into the extracellular space through opening of pannexin-1 channels that signalled through P2X7 receptors to deliver a critical co-stimulatory signal that activated the NLRP3 inflammasome. Both the cysteine protease activity and integrin-binding domain of EhCP5 were required to trigger α5β1 integrin that led to ATP release and NLRP3 inflammasome activation. These findings reveal engagement of α5β1 integrin across the parasite-host junction is a key regulatory step that initiates robust inflammatory responses to Eh. We propose that α5β1 integrin distinguishes Eh direct contact and functions with NLRP3 as pathogenicity sensor for invasive Eh infection.

  13. Influence of parasite density and sample storage time on the reliability of Entamoeba histolytica-specific PCR from formalin-fixed and paraffin-embedded tissues.

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    Frickmann, Hagen; Tenner-Racz, Klara; Eggert, Petra; Schwarz, Norbert G; Poppert, Sven; Tannich, Egbert; Hagen, Ralf M

    2013-12-01

    We report on the reliability of polymerase chain reaction (PCR) for the detection of Entamoeba histolytica from formalin-fixed, paraffin-embedded tissue in comparison with microscopy and have determined predictors that may influence PCR results. E. histolytica-specific and Entamoeba dispar-specific real-time PCR and microscopy from adjacent histologic sections were performed using a collection of formalin-fixed, paraffin-embedded tissue specimens obtained from patients with invasive amebiasis. Specimens had been collected during the previous 4 decades. Association of sample age, parasite density, and reliability of PCR was analyzed. E. histolytica PCR was positive in 20 of 34 biopsies (58.8%); 2 of these 20 were microscopically negative for amebae in neighboring tissue sections. PCR was negative in 9 samples with visible amebae in neighboring sections and in 5 samples without visible parasites in neighboring sections. PCR was negative in all specimens that were older than 3 decades. Low parasite counts and sample ages older than 20 years were predictors for false-negative PCR results. All samples were negative for E. dispar DNA. PCR is suitable for the detection of E. histolytica in formalin-fixed, paraffin-embedded tissue samples that are younger than 2 decades and that contain intermediate to high parasite numbers. Negative results in older samples were due to progressive degradation of DNA over time as indicated by control PCRs targeting the human 18S rRNA gene. Moreover, our findings support previous suggestions that only E. histolytica but not E. dispar is responsible for invasive amebiasis.

  14. [Comparison of direct microscopy, culture, ELISA and molecular methods for diagnosis of Entamoeba histolytica].

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    Tüzemen, Nazmiye Ulkü; Doğan, Nihal

    2014-01-01

    Amebiasis, a parasitic infection caused by Entamoeba histolytica, is one of the most common parasitic infections worldwide. Since it is still an important public health problem in developing countries, rapid differential diagnosis of amebiasis is crucial in terms of treatment. The most frequently used method for laboratory diagnosis is direct microscopy, however more reliable and specific methods are needed in order to differentiate the apathogenic Entamoeba dispar under the microscope. This study was conducted to compare the results of different methods namely, direct microscopy, culture, ELISA and PCR for the detection of E.histolytica in stool samples and to evaluate the performances of those methods. A total of 1049 stool samples collected from pediatric and adult patients who were admitted to hospital with diarrhea complaint between January 2011-March 2013, and randomly selected samples from primary school children, were included in the study. Direct microscopic examination was performed by native-lugol, physiological saline, modified formol-ethyl acetate sedimentation and trichrome staining methods. The stool samples were also inoculated into TYI-S-33 media for axenic cultivation of amoeba. The presence of amebic antigens in the samples were screened by a commercial ELISA kit (TechLab, E.histolytica II, USA). For the molecular diagnosis, a multiplex tandem real-time PCR (MT-PCR) kit (AusDiagnostics Pty Ltd, Australia) was used, after the extraction of DNAs with QIAamp DNA Stool Mini Kit (Qiagen, USA). A total of 354 samples which could be evaluated by all of the methods, were included in the study. Of the 354 stool samples, 84 (23.7%) were found E.histolytica/E.dispar positive by direct microscopy, 61 (17.2%) by trichrome staining, 46 (12.9%) by culture, 31 (8.7%) by ELISA and 9 (2.5%) by MT-PCR. Of direct microscopy positive samples 54.7% (46/84) were also positive with trichrome staining, 39.3% (33/84) with culture, 15.5% (13/84) with ELISA and 7.1% (6

  15. Proteomic Identification of S-Nitrosylated Proteins in the Parasite Entamoeba histolytica by Resin-Assisted Capture: Insights into the Regulation of the Gal/GalNAc Lectin by Nitric Oxide

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    Hertz, Rivka; Ben Lulu, Shani; Shahi, Preeti; Trebicz-Geffen, Meirav; Benhar, Moran; Ankri, Serge

    2014-01-01

    Entamoeba histolytica is a gastrointestinal protozoan parasite that causes amebiasis, a disease which has a worldwide distribution with substantial morbidity and mortality. Nitrosative stress, which is generated by innate immune cells, is one of the various environmental challenges that E. histolytica encounters during its life cycle. Although the effects of nitric oxide (NO) on the regulation of gene expression in this parasite have been previously investigated, our knowledge on S-nitrosylated proteins in E.histolytica is lacking. In order to fill this knowledge gap, we performed a large-scale detection of S-nitrosylated (SNO) proteins in E.histolytica trophozoites that were treated with the NO donor, S-nitrosocysteine by resin-assisted capture (RAC). We found that proteins involved in glycolysis, gluconeogenesis, translation, protein transport, and adherence to target cells such as the heavy subunit of Gal/GalNac lectin are among the S-nitrosylated proteins that were enriched by SNO-RAC. We also found that the S-nitrosylated cysteine residues in the carbohydrate recognition domain (CRD) of Gal/GalNAc lectin impairs its function and contributes to the inhibition of E.histolytica adherence to host cells. Collectively, these results advance our understanding of the mechanism of reduced E.histolytica adherence to mammalian cells by NO and emphasize the importance of NO as a regulator of key physiological functions in E.histolytica. PMID:24626316

  16. Proteomic identification of S-nitrosylated proteins in the parasite Entamoeba histolytica by resin-assisted capture: insights into the regulation of the Gal/GalNAc lectin by nitric oxide.

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    Rivka Hertz

    Full Text Available Entamoeba histolytica is a gastrointestinal protozoan parasite that causes amebiasis, a disease which has a worldwide distribution with substantial morbidity and mortality. Nitrosative stress, which is generated by innate immune cells, is one of the various environmental challenges that E. histolytica encounters during its life cycle. Although the effects of nitric oxide (NO on the regulation of gene expression in this parasite have been previously investigated, our knowledge on S-nitrosylated proteins in E.histolytica is lacking. In order to fill this knowledge gap, we performed a large-scale detection of S-nitrosylated (SNO proteins in E.histolytica trophozoites that were treated with the NO donor, S-nitrosocysteine by resin-assisted capture (RAC. We found that proteins involved in glycolysis, gluconeogenesis, translation, protein transport, and adherence to target cells such as the heavy subunit of Gal/GalNac lectin are among the S-nitrosylated proteins that were enriched by SNO-RAC. We also found that the S-nitrosylated cysteine residues in the carbohydrate recognition domain (CRD of Gal/GalNAc lectin impairs its function and contributes to the inhibition of E.histolytica adherence to host cells. Collectively, these results advance our understanding of the mechanism of reduced E.histolytica adherence to mammalian cells by NO and emphasize the importance of NO as a regulator of key physiological functions in E.histolytica.

  17. The monocyte locomotion inhibitory factor an anti-inflammatory peptide; therapeutics originating from amebic abscess of the liver.

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    Velazquez, Juan R

    2011-01-01

    Entamoeba histolytica in culture produces a pentapeptide (MQCNS). This oligopeptide inhibits the in vitro and in vivo locomotion of human monocytes, hence its denomination Monocyte Locomotion Inhibitory Factor (MLIF). The original isolated peptide and its synthetic construct display similar effects, among others, being inhibition of the respiratory burst in monocytes and neutrophils, decrease of Dinitrochlorobenzene (DNCB) skin hypersensitivity in guinea pigs and gerbils, and delay of mononuclear leukocytes in human Rebuck skin windows with inhibition of vascular cell Very late antigen (VLA)-4 and Vascular adhesion molecules (VCAM) in endothelia and monocytes. The MLIF molecular mechanism of action is unknown, but data reveal its implication in Nuclear factor-kappa B (NF-κB) and Mitogenactivated protein kinase (MAPK) pathways. This could explain MLIF multiplicity of biological effects. On the other hand, the amebic peptide has been useful in treating experimental amebiasis of the liver. The amebic peptide is effective in reducing inflammation induced by carragenin and arthritis in a Collagen-induced arthritis (CIA) model. Microarray data from experimental arthritis revealed an MLIF gene expression profile that includes genes that are involved in apoptosis, cell adhesion, extracellular matrix, and inflammation / chemotaxis. MLIF could be involved in unsuspected biological factions because there is increasing data on the peptide effect on several cell activities. This review also presents uses of MLIF as described in patents.

  18. Entamoeba histolytica Cysteine Proteinase 5 Evokes Mucin Exocytosis from Colonic Goblet Cells via αvβ3 Integrin.

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    Steve Cornick

    2016-04-01

    Full Text Available Critical to the pathogenesis of intestinal amebiasis, Entamoeba histolytica (Eh induces mucus hypersecretion and degrades the colonic mucus layer at the site of invasion. The parasite component(s responsible for hypersecretion are poorly defined, as are regulators of mucin secretion within the host. In this study, we have identified the key virulence factor in live Eh that elicits the fast release of mucin by goblets cells as cysteine protease 5 (EhCP5 whereas, modest mucus secretion occurred with secreted soluble EhCP5 and recombinant CP5. Coupling of EhCP5-αvβ3 integrin on goblet cells facilitated outside-in signaling by activating SRC family kinases (SFK and focal adhesion kinase that resulted in the activation/phosphorlyation of PI3K at the site of Eh contact and production of PIP3. PKCδ was activated at the EhCP5-αvβ3 integrin contact site that specifically regulated mucin secretion though the trafficking vesicle marker myristoylated alanine-rich C-kinase substrate (MARCKS. This study has identified that EhCP5 coupling with goblet cell αvβ3 receptors can initiate a signal cascade involving PI3K, PKCδ and MARCKS to drive mucin secretion from goblet cells critical in disease pathogenesis.

  19. Data set for the proteomics analysis of the endomembrane system from the unicellular Entamoeba histolytica

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    Doranda Perdomo

    2014-12-01

    Full Text Available Entamoeba histolytica is the protozoan parasite agent of amebiasis, an infectious disease of the human intestine and liver. This parasite contact and kills human cells by an active process involving pathogenic factors. Cellular traffic and secretion activities are poorly characterized in E. histolytica. In this work, we took advantage of a wide proteomic analysis to search for principal components of the endomembrane system in E. histolytica. A total of 5683 peptides matching with 1531 proteins (FDR of 1% were identified which corresponds to roughly 20% of the total amebic proteome. Bioinformatics investigations searching for domain homologies (Smart and InterProScan programs and functional descriptions (KEGG and GO terms allowed this data to be organized into distinct categories. This data represents the first in-depth proteomics analysis of subcellular compartments in E. histolytica and allows a detailed map of vesicle traffic components in an ancient single-cell organism that lacks a stereotypical ER and Golgi apparatus to be established. The data are related to [1].

  20. Acute diarrhea in children

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    Radlović Nedeljko

    2015-01-01

    Full Text Available Acute diarrhea (AD is the most frequent gastroenterological disorder, and the main cause of dehydration in childhood. It is manifested by a sudden occurrence of three or more watery or loose stools per day lasting for seven to 10 days, 14 days at most. It mainly occurs in children until five years of age and particularly in neonates in the second half-year and children until the age of three years. Its primary causes are gastrointestinal infections, viral and bacterial, and more rarely alimentary intoxications and other factors. As dehydration and negative nutritive balance are the main complications of AD, it is clear that the compensation of lost body fluids and adequate diet form the basis of the child’s treatment. Other therapeutic measures, except antipyretics in high febrility, antiparasitic drugs for intestinal lambliasis, anti-amebiasis and probiotics are rarely necessary. This primarily regards uncritical use of antibiotics and intestinal antiseptics in the therapy of bacterial diarrhea. The use of antiemetics, antidiarrhetics and spasmolytics is unnecessary and potentially risky, so that it is not recommended for children with AD.

  1. A review of the proposed role of neutrophils in rodent amebic liver abscess models

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    Campos-Rodríguez Rafael

    2016-01-01

    Full Text Available Host invasion by Entamoeba histolytica, the pathogenic agent of amebiasis, can lead to the development of amebic liver abscess (ALA. Due to the difficulty of exploring host and amebic factors involved in the pathogenesis of ALA in humans, most studies have been conducted with animal models (e.g., mice, gerbils, and hamsters. Histopathological findings reveal that the chronic phase of ALA in humans corresponds to lytic or liquefactive necrosis, whereas in rodent models there is granulomatous inflammation. However, the use of animal models has provided important information on molecules and mechanisms of the host/parasite interaction. Hence, the present review discusses the possible role of neutrophils in the effector immune response in ALA in rodents. Properly activated neutrophils are probably successful in eliminating amebas through oxidative and non-oxidative mechanisms, including neutrophil degranulation, the generation of free radicals (O2−, H2O2, HOCl and peroxynitrite, the activation of NADPH-oxidase and myeloperoxidase (MPO enzymes, and the formation of neutrophil extracellular traps (NETs. On the other hand, if amebas are not eliminated in the early stages of infection, they trigger a prolonged and exaggerated inflammatory response that apparently causes ALAs. Genetic differences in animals and humans are likely to be key to a successful host immune response.

  2. [Clinical microbiology laboratory and imported parasitic diseases].

    Science.gov (United States)

    Martín-Rabadán, Pablo; Martínez-Ruiz, Rocío; Cuadros, Juan; Cañavate, Carmen

    2010-12-01

    Imported parasitosis represents an increasingly frequent diagnostic challenge for microbiology laboratories. A surge in immigration and international travel has led to a rise in the number of imported cases of parasitosis, and this trend is expected to continue in the future. The present article addresses this challenge by reviewing recommended diagnostic approaches and tests. Currently, microscopy is always recommended when analysing blood samples for parasites. If malaria is suspected, rapid antigen testing (including at least HRP2 antigen) should also be performed. The work-up for suspected leishmaniasis should include serology, culture, and in selected cases detection of antigen in urine. In suspected Chagas disease, two different serological tests should be performed. PCR for blood protozoa is highly sensitive, although it cannot be used to rule out Chagas disease, since this condition may be present without parasitemia. Accurate diagnosis of intestinal amebiasis usually requires PCR or antigen detection tests. In helminthiasis, traditional microscopy may need to be complemented with other tests, such as agar plate culture for strongyloidiasis, Og4C3 antigen detection for bancroftian filariasis, and antibody detection test for filariasis and schistosomiasis.

  3. Parasitic diseases of zoonotic importance in humans of northeast India, with special reference to ocular involvement

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    Das D

    2014-09-01

    Full Text Available Dipankar Das,1 Saidul Islam,2 Harsha Bhattacharjee,1 Angshuman Deka,1 Dinakumar Yambem,1 Prerana Sushil Tahiliani,1 Panna Deka,1 Pankaj Bhattacharyya,1 Satyen Deka,1 Kalyan Das,1 Gayatri Bharali,1 Apurba Deka,1 Rajashree Paul1 1Sri Sankaradeva Nethralaya, Guwahati, 2Department of Parasitology, College of Veterinary Science, Assam Agricultural University, Guwahati, Assam, India Abstract: Parasitic zoonotic diseases are prevalent in India, including the northeastern states. Proper epidemiological data are lacking from this part of the country on zoonotic parasitic diseases, and newer diseases are emerging in the current scenario. Systemic manifestation of such diseases as cysticercosis, paragonimiasis, hydatidosis, and toxoplasmosis are fairly common. The incidence of acquired toxoplasmal infection is showing an increasing trend in association with acquired immunodeficiency syndrome. Among the ocular parasitic diseases, toxoplasmosis, cysticercosis, toxocariasis, dirofilariasis, gnathostomiasis, hydatidosis, amebiasis, giardiasis, etc, are the real problems that are seen in this subset of the population. Therefore, proper coordination between various medical specialities, including veterinary science and other governing bodies, is needed for better and more effective strategic planning to control zoonoses. Keywords: zoonoses, regional infections, toxoplasmosis, cysticercosis, toxocariasis, hydatidosis 

  4. [Parasitology and entomology in the 29th century in Latin American narrative].

    Science.gov (United States)

    Schenone, H

    2000-01-01

    In the present review of twelve pieces produced by distinguished 20th century Latin American writers--Jorge Luis Borges from Argentina, Jorge Amado and João Ubaldo Ribeiro from Brazil, José Donoso from Chile, Gabriel García Márquez from Colombia, Alejo Carpentier from Cuba, Miguel Angel Asturias from Guatemala, Octavio Paz from Mexico, Mario Vargas Llosa from Perú, Horacio Quiroga and Mario Benedetti from Uruguay and Arturo Uslar-Pietri from Venezuela--paragraphs or parts of paragraphs in which parasitological or entomological situations of the most varied hues are referred to or described, have been extracted in a selective form. Sometimes in these descriptions appear, local or regional expressions, without ignoring colorful folklore representations. For a easier interpretation these or part of these paragraph sentences have been arranged by thematic similarities. In a varied and kaleidoscopic vision, it will be possible to find protozoiasis (malaria, Chagas disease, leishmaniasis, amebiasis), helminthiases (ascariasis, hydatidosis, trichinosis, schistosomiasis, cysticercosis, onchocerciasis), parasitoses produced by arthropods (pediculosis, scabies, tungiasis, myiasis), passing progressively to hemaphagous arthropods (mosquitoes, gnats, horse flies, bedbugs, ticks), venomous arthropods (Latrodectus spiders, scorpions, wasps, bees), mechanical vectors (flies and cockroaches), culminating with a conjunction of bucolic arthropods (butterflies, crickets, grasshoppers cicadas, ants, centipedes, beetles, glow worms, dragonflies).

  5. N-acetyl ornithine deacetylase is a moonlighting protein and is involved in the adaptation of Entamoeba histolytica to nitrosative stress

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    Shahi, Preeti; Trebicz-Geffen, Meirav; Nagaraja, Shruti; Hertz, Rivka; Alterzon-Baumel, Sharon; Methling, Karen; Lalk, Michael; Mazumder, Mohit; Samudrala, Gourinath; Ankri, Serge

    2016-01-01

    Adaptation of the Entamoeba histolytica parasite to toxic levels of nitric oxide (NO) that are produced by phagocytes may be essential for the establishment of chronic amebiasis and the parasite’s survival in its host. In order to obtain insight into the mechanism of E. histolytica’s adaptation to NO, E. histolytica trophozoites were progressively adapted to increasing concentrations of the NO donor drug, S-nitrosoglutathione (GSNO) up to a concentration of 110 μM. The transcriptome of NO adapted trophozoites (NAT) was investigated by RNA sequencing (RNA-seq). N-acetyl ornithine deacetylase (NAOD) was among the 208 genes that were upregulated in NAT. NAOD catalyzes the deacetylation of N-acetyl-L-ornithine to yield ornithine and acetate. Here, we report that NAOD contributes to the better adaptation of the parasite to nitrosative stress (NS) and that this function does not depend on NAOD catalytic activity. We also demonstrated that glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is detrimental to E. histolytica exposed to NS and that this detrimental effect is neutralized by NAOD or by a catalytically inactive NAOD (mNAOD). These results establish NAOD as a moonlighting protein, and highlight the unexpected role of this metabolic enzyme in the adaptation of the parasite to NS. PMID:27808157

  6. Activity, stability and folding analysis of the chitinase from Entamoeba histolytica.

    Science.gov (United States)

    Muñoz, Patricia L A; Minchaca, Alexis Z; Mares, Rosa E; Ramos, Marco A

    2016-02-01

    Human amebiasis, caused by the parasitic protozoan Entamoeba histolytica, remains as a significant public health issue in developing countries. The life cycle of the parasite compromises two main stages, trophozoite and cyst, linked by two major events: encystation and excystation. Interestingly, the cyst stage has a chitin wall that helps the parasite to withstand harsh environmental conditions. Since the amebic chitinase, EhCHT1, has been recognized as a key player in both encystation and excystation, it is plausible to consider that specific inhibition could arrest the life cycle of the parasite and, thus, stop the infection. However, to selectively target EhCHT1 it is important to recognize its unique biochemical features to have the ability to control its cellular function. Hence, to gain further insights into the structure-function relationship, we conducted an experimental approach to examine the effects of pH, temperature, and denaturant concentration on the enzymatic activity and protein stability. Additionally, dependence on in vivo oxidative folding was further studied using a bacterial model. Our results attest the potential of EhCHT1 as a target for the design and development of new or improved anti-amebic therapeutics. Likewise, the potential of the oxidoreductase EhPDI, involved in oxidative folding of amebic proteins, was also confirmed.

  7. Entamoeba histolytica contains an occludin-like protein that can alter colonic epithelial barrier function.

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    Goplen, Michael; Lejeune, Manigandan; Cornick, Steve; Moreau, France; Chadee, Kris

    2013-01-01

    The exact mechanism by which Entamoeba histolytica disrupts the human colonic epithelium and invades the mucosa has yet to be clearly elucidated. E. histolytica produces a diverse array of putative virulent factors such as glycosidase, cysteine proteinases and amebapore that can modulate and/or disrupt epithelial barrier functions. However, it is currently thought that E. histolytica produces numerous other molecules and strategies to disrupt colonic mucosal defenses. In this study, we document a putative mechanism whereby the parasite alters the integrity of human epithelium by expressing a cognate tight junction protein of the host. We detected this protein as "occludin-like" as revealed by immunoblotting and immunoprecipitation studies and visualization by confocal microscopy using antibodies highly specific for human occludin. We propose that E. histolytica occludin-like protein might displace mucosal epithelial occludin-occludin tight junction interactions resulting in epithelial disruption analogous to sub mucosal human dendritic cells sampling luminal contents. These results indicate that E. histolytica occludin is a putative virulent component that can play a role in the pathogenesis of intestinal amebiasis.

  8. Erythrophagocytosis in Entamoeba histolytica and Entamoeba dispar: a comparative study.

    Science.gov (United States)

    Talamás-Lara, Daniel; Chávez-Munguía, Bibiana; González-Robles, Arturo; Talamás-Rohana, Patricia; Salazar-Villatoro, Lizbeth; Durán-Díaz, Ángel; Martínez-Palomo, Adolfo

    2014-01-01

    Entamoeba histolytica is the causative agent of human intestinal and liver amebiasis. The extraordinary phagocytic activity of E. histolytica trophozoites has been accepted as one of the virulence mechanisms responsible for their invasive capacity. The recognition of the noninvasive Entamoeba dispar as a different species has raised the question as to whether the lack of pathogenic potential of this ameba correlates with a limited phagocytic capacity. We have therefore compared the process of erythrophagocytosis in both species by means of light and video microscopy, hemoglobin measurement, and the estimation of reactive oxygen species (ROS). In the present study, we confirmed that E. dispar has lower erythrophagocytic capacity. We also observed by video microscopy a new event of erythrocyte opsonization-like in both species, being more characteristic in E. histolytica. Moreover, E. dispar showed a lower capacity to produce ROS compared with the invasive species and also showed a large population of amoebae that did not engulf any erythrocyte over time. Our results demonstrate that E. histolytica has a higher phagocytic capacity than E. dispar, including a higher rate of production of ROS in the course of ingesting red blood cells.

  9. Susceptibility testing of Entamoeba histolytica

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    Cedeno, J.R.; Krogstad, D.J.

    1983-12-01

    The growth of Entamoeba histolytica in microtiter plates in vitro in a variety of environments with reduced oxygen tensions is reported. With 3% O/sub 2/, 3% CO/sub 2/, and 94% N/sub 2/, the parasite growth in microtiter plates was identical to that in screw-capped culture tubes, as measured by (/sup 3/H)thymidine incorporation and by quantitative parasite counts. There were no significant differences between the drug concentrations necessary to inhibit parasite growth by 50% based on (/sup 3/H)thymidine incorporation vs those defined by quantitative parasite counts for the 15 antimicrobial agents tested (including seven drugs used for the treatment of amebiasis). This technique provides a reproducible method to quantitate the activity of potential antiamebic agents in vitro. The isotopic method should be of particular value in defining the metabolism of the parasite and effects of antimicrobial agents on it, whereas the morphologic method may be more valuable for workers with limited resources available to them.

  10. A whole-genome RNAi screen uncovers a novel role for human potassium channels in cell killing by the parasite Entamoeba histolytica.

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    Marie, Chelsea; Verkerke, Hans P; Theodorescu, Dan; Petri, William A

    2015-09-08

    The parasite Entamoeba histolytica kills human cells resulting in ulceration, inflammation and invasion of the colonic epithelium. We used the cytotoxic properties of ameba to select a genome-wide RNAi library to reveal novel host factors that control susceptibility to amebic killing. We identified 281 candidate susceptibility genes and bioinformatics analyses revealed that ion transporters were significantly enriched among susceptibility genes. Potassium (K(+)) channels were the most common transporter identified. Their importance was further supported by colon biopsy of humans with amebiasis that demonstrated suppressed K(+) channel expression. Inhibition of human K(+) channels by genetic silencing, pharmacologic inhibitors and with excess K(+) protected diverse cell types from E. histolytica-induced death. Contact with E. histolytica parasites triggered K(+) channel activation and K(+) efflux by intestinal epithelial cells, which preceded cell killing. Specific inhibition of Ca(2+)-dependent K(+) channels was highly effective in preventing amebic cytotoxicity in intestinal epithelial cells and macrophages. Blockade of K(+) efflux also inhibited caspase-1 activation, IL-1β secretion and pyroptotic death in THP-1 macrophages. We concluded that K(+) channels are host mediators of amebic cytotoxicity in multiple cells types and of inflammasome activation in macrophages.

  11. Entamoeba histolytica and E. dispar infections in captive macaques (Macaca fascicularis) in the Philippines.

    Science.gov (United States)

    Rivera, Windell L; Yason, John Anthony D L; Adao, Davin Edric V

    2010-01-01

    Entamoeba histolytica is a protozoan parasite that infects man and animals. This parasite has a global distribution and the disease it causes is usually characterized by diarrhea. In order to detect the parasite, it is necessary to differentiate it from Entamoeba dispar. E. dispar appears morphologically similar to E. histolytica but does not cause disease and tissue invasion. This study reports on the prevalence of E. histolytica and E. dispar among captive macaques in a primate facility in the Philippines. PCR was used to correctly identify both Entamoeba species. Indirect fluorescent antibody test (IFAT) was also performed to determine the seroprevalence of amebiasis in the captive macaques. Based on PCR targeting of the peroxiredoxin gene, of the 96 stool samples collected, 23 (24%) contained E. histolytica while 32 (33%) contained E. dispar. IFAT revealed 26 (27%) serum samples positive for antibodies against E. histolytica. Sequence analysis of the 18S rRNA gene showed that the 23 E. histolytica isolates were identical to human E. histolytica isolates deposited in the GenBank and not Entamoeba nuttalli as found in macaques in other recent reports. The Philippines is a major exporter of monkeys for biomedical research purposes, so screening animals before transporting them to other locations lessens the risk of spreading zoonoses to a wider area. This is the first report of the molecular detection of E. histolytica and E. dispar among macaques in the Philippines. This study complements the limited information available on the animal hosts of E. histolytica in the Philippines.

  12. Prevalence of Entamoeba histolytica/Entamoeba dispar in the city of Campina Grande, in northeastern Brazil.

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    Silva, Maria Teresa Nascimento; Santana, José Valfrido; Bragagnoli, Gérson; Marinho, Alexandre Magno da Nóbrega; Malagueño, Elizabeth

    2014-01-01

    There is a clear need to perform epidemiological studies to find the true prevalence of Entamoeba histolytica around the world. The evaluation of this prevalence has been hindered by the existence of two different species which are morphologically identical, but genetically different, namely E. histolytica, which causes amebiasis, and E. dispar, which is non-pathogenic. In Brazil, the E. dispar has been detected in communities in the Southeastern (SE) and Northeastern (NE) regions with poor sanitation. However, individuals infected with E. histolytica have been identified in other regions. There is an absence of reports on the prevalence of these parasites in the state of Paraíba, which also has areas with poor sanitary conditions where a high prevalence of the E. histolytica/E. dispar complex has been detected in children from urban slums. The present study evaluated the prevalence of E. histolytica and E. dispar in 1,195 asymptomatic children between two and 10 years of age, living in a sprawling urban slum in Campina Grande, in the state of Paraíba, in Northeastern Brazil. These children were examined and their feces samples were analyzed microscopically. A total of 553 children tested positive for the E. histolytica/E. dispar complex, and 456 of the positive samples were tested with the E. histolytica II® ELISA kit. All 456 samples were negative for the presence of the adhesin E. histolytica specific antigen. The evidence suggests that in this community E. histolytica is absent and E. dispar is the dominant species.

  13. Insights into Entamoeba histolytica virulence modulation.

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    Padilla-Vaca, F; Anaya-Velázquez, F

    2010-08-01

    Entamoeba histolytica is able to invade human tissues by means of several molecules and biological properties related to the virulence. Pathogenic amebas use three major virulence factors, Gal/GalNAc lectin, amebapore and proteases, for lyse, phagocytose, kill and destroy a variety of cells and tissues in the host. Responses of the parasite to host components such as mucins and bacterial flora influence the behavior of pathogenic amebas altering their expression of virulence factors. The relative virulence of different strains of E. histolytica has been shown to vary as a consequence of changes in conditions of in vitro cultivation which implies substantial changes in basic metabolic aspects and factors directly and indirectly related to amebic virulence. Comparison of E. histolytica strains with different virulence phenotypes and under different conditions of growth will help to identify new virulence factor candidates and define the interplay between virulence factors and invasive phenotype. Virulence attenuate mutants of E. histolytica are useful also to uncover novel virulence determinants. The comparison of biological properties and virulence factors between E. histolytica and E. dispar, a non-pathogenic species, has been a useful approach to investigate the key factors involved in the experimental presentation of amebiasis and its complex regulation. The molecular mechanisms that regulate these variations in virulence are not yet known. Their elucidation will help us to better understand the gene expression plasticity that enables the effective adaptation of the ameba to changes in growth culture conditions and host factors.

  14. Amoebic PI3K and PKC is required for Jurkat T cell death induced by Entamoeba histolytica.

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    Lee, Young Ah; Kim, Kyeong Ah; Min, Arim; Shin, Myeong Heon

    2014-08-01

    The enteric protozoan parasite Entamoeba histolytica is the causative agent of human amebiasis. During infection, adherence of E. histolytica through Gal/GalNAc lectin on the surface of the amoeba can induce caspase-3-dependent or -independent host cell death. Phosphorylinositol 3-kinase (PI3K) and protein kinase C (PKC) in E. histolytica play an important function in the adhesion, killing, or phagocytosis of target cells. In this study, we examined the role of amoebic PI3K and PKC in amoeba-induced apoptotic cell death in Jurkat T cells. When Jurkat T cells were incubated with E. histolytica trophozoites, phosphatidylserine (PS) externalization and DNA fragmentation in Jurkat cells were markedly increased compared to those of cells incubated with medium alone. However, when amoebae were pretreated with a PI3K inhibitor, wortmannin before being incubated with E. histolytica, E. histolytica-induced PS externalization and DNA fragmentation in Jurkat cells were significantly reduced compared to results for amoebae pretreated with DMSO. In addition, pretreatment of amoebae with a PKC inhibitor, staurosporine strongly inhibited Jurkat T cell death. However, E. histolytica-induced cleavage of caspase-3, -6, and -7 were not inhibited by pretreatment of amoebae with wortmannin or staurosporin. In addition, we found that amoebic PI3K and PKC have an important role on amoeba adhesion to host compartment. These results suggest that amebic PI3K and PKC activation may play an important role in caspase-independent cell death in Entamoeba-induced apoptosis.

  15. A Toll/IL-1R/resistance domain-containing thioredoxin regulates phagocytosis in Entamoeba histolytica

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    Mancilla-Herrera Ismael

    2012-10-01

    Full Text Available Abstract Background Entamoeba histolytica is a protozoan parasite that infects humans and causes amebiasis affecting developing countries. Phagocytosis of epithelial cells, erythrocytes, leucocytes, and commensal microbiota bacteria is a major pathogenic mechanism used by this parasite. A Toll/IL-1R/Resistance (TIR domain-containing protein is required in phagocytosis in the social ameba Dictyostelium discoideum, an ameba closely related to Entamoeba histolytica in phylogeny. In insects and vertebrates, TIR domain-containing proteins regulate phagocytic and cell activation. Therefore, we investigated whether E. histolytica expresses TIR domain-containing molecules that may be involved in the phagocytosis of erythrocytes and bacteria. Methods Using in silico analysis we explored in Entamoeba histolytica databases for TIR domain containing sequences. After silencing TIR domain containing sequences in trophozoites by siRNA we evaluated phagocytosis of erythrocytes and bacteria. Results We identified an E. histolytica thioredoxin containing a TIR-like domain. The secondary and tertiary structure of this sequence exhibited structural similarity to TIR domain family. Thioredoxin transcripts silenced in E. histolytica trophozoites decreased erythrocytes and E. coli phagocytosis. Conclusion TIR domain-containing thioredoxin of E. histolytica could be an important element in erythrocytes and bacteria phagocytosis.

  16. Ensaio clinico com Teclozan: 500mg no tratamento da colite amebiana não disentérica. (Resultados com esquema terapêutico de 24 horas

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    Donald Huggins

    1978-12-01

    Full Text Available O Autor relata sua experiência com novo esquema terapêutico com Teclozan - dose total de 1.500mg empregada em 24 horas, em 40 pacientes portadores de colite amebiana não disentérica na Disciplina de Doenças Infecciosas e Parasitárias da Universidade Federal de Pernambuco. Após um controle de cura realizado no 4º, 8º, 12º e 20º dias após o tratamento, obteve eficácia em 75% dos enfermos (30 casos e excelente tolerância.The author report his experience with Teclozine in the treatment on 40 patients suffering chronic intestinal amebiasis, employing a new therapeutical schedule - 1,500 mg as the total dose, within the period of 24 hours. After a follow-up on the 4th, 8th, 12th, and 20th days of treatment, the parasitological cure rate obtained was 75% (30 cases, and the drug was very well tolerated by all the patients.

  17. Entamoeba histolytica: Adhesins and Lectins in the Trophozoite Surface

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    Magdalena Aguirre García

    2015-02-01

    Full Text Available Entamoeba histolytica is the causative agent of amebiasis in humans and is responsible for 100,000 deaths annually, making it the third leading cause of death due to a protozoan parasite. Pathogenesis appears to result from the potent cytotoxic activity of the parasite, which kills host cells within minutes. Although the mechanism is unknown, it is well established to be contact-dependent. The life cycle of the parasite alternates with two forms: the resistant cyst and the invasive trophozoite. The adhesive interactions between the parasite and surface glycoconjugates of host cells, as well as those lining the epithelia, are determinants for invasion of human tissues, for its cytotoxic activity, and finally for the outcome of the disease. In this review we present an overview of the information available on the amebic lectins and adhesins that are responsible of those adhesive interactions and we also refer to their effect on the host immune response. Finally, we present some concluding remarks and perspectives in the field.

  18. [Parasitosis and irritable bowel syndrome].

    Science.gov (United States)

    Ibarra, Catalina; Herrera, Valentina; Pérez de Arce, Edith; Gil, Luis Carlos; Madrid, Ana María; Valenzuela, Lucía; Beltrán, Caroll J

    2016-06-01

    Irritable bowel syndrome (IBS) is a functional disorder of the gastrointestinal tract characterised by multi-factorial aetiology. In IBS physiopathology are involved diverse factors between them biological, psychosocial, and environmental components which affect the immune activation status of gut mucosa. Among these factors is recognized the intestinal parasitosis. Post-infection IBS (PI-IBS) is recognised as a subgroup of functional disorders whose symptoms onset appear after a symptomatic intestinal infection caused by microbial agents. There are few studies regarding of relationship between IBS and intestinal parasitosis in Chile. However, is has been well described a positive association between IBS and Blastocystis hominis infections, one of prevalent parasites in Chile. In other countries, is also described a relationship between IBS and amebiasis and giardiasis. Both, characterized by a common mode of transmission through water as well as contaminated food. Because the high prevalence of parasitosis in our country it is necessary to expand the association studies to clarify the strength of the parasites ethiology in IBS.

  19. Dehydroepiandrosterone decreases while cortisol increases in vitro growth and viability of Entamoeba histolytica.

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    Carrero, Julio C; Cervantes, Claudia; Moreno-Mendoza, Norma; Saavedra, Emma; Morales-Montor, Jorge; Laclette, Juan P

    2006-02-01

    In vitro exposure of Entamoeba histolytica trophozoites to the sex steroids 17beta-estradiol, progesterone, and dehydrotestosterone had little effect on parasite viability or proliferation. However, treatment with the adrenal steroid dehydroepiandrosterone (DHEA) markedly inhibited parasite proliferation, adherence and motility, and at a certain dose it induced trophozoite lysis. The opposite effect on proliferation was found when the trophozoites were exposed to cortisol. Moreover, DHEA decreased while cortisol increased the parasite's DNA synthesis determined by 3H-thymidine incorporation. Trophozoite lysis by DHEA appeared to be caused by a necrotic rather than an apoptotic process, as observed in propidium iodide and terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling assays. A possible mechanisms of action was derived from experiments demonstrating that the activity of a putative 3-hydroxy-3-methyl glutaryl CoA reductase detected in trophozoite extracts was inhibited in the presence of DHEA. Contrary to its in vitro inhibitory effect, in vivo administration of DHEA to infected hamsters resulted in exacerbation of the amebic liver abscesses. These results demonstrated that androgen steroids act directly upon E. histolytica growth and viability, and may shed new light on some age and gender differences in disease progression, as well as finding application in the drug treatment of human amebiasis.

  20. Activation of dendritic cells by the Gal-lectin of Entamoeba histolytica drives Th1 responses in vitro and in vivo.

    Science.gov (United States)

    Ivory, Catherine P A; Chadee, Kris

    2007-02-01

    Amebiasis is a human disease caused by the protozoan intestinal parasite Entamoeba histolytica. Vaccine development has focused on the parasite's surface galactose-N-acetyl-D-galactosamine inhibitable lectin (Gal-lectin) as a protective antigen. The Gal-lectin is immunogenic and has been shown to induce Th1 cytokines in vitro and in vivo. The immunological basis of the protective immune response elicited by the Gal-lectin is unknown. In this study, we investigated the response of BALB/c bone marrow-derived DC to E. histolytica Gal-lectin. Incubation of immature DC with Gal-lectin resulted in activation and maturation after 24 h. FACS analysis demonstrated an up-regulation of DC maturation markers CD80, CD86, CD40 and MHC class II upon exposure to Gal-lectin. The Gal-lectin also induced DC production of IL-12, indicating a Th1 response. Gal-lectin-activated DC were able to stimulate T cell proliferation in an allogeneic mixed leukocyte reaction and adoptive transfer of Gal-lectin-treated DC into naïve mice resulted in IFN-gamma-producing Gal-lectin-sensitized T cells. The activation of DC by Gal-lectin was mediated by MAPK and NF-kappaB. These findings indicate that E. histolytica Gal-lectin is a potent vaccine antigen capable of directly initiating DC maturation and activation characterized by Th1 cytokine production.

  1. A novel anti-inflammatory oligopeptide produced by Entamoeba histolytica.

    Science.gov (United States)

    Kretschmer, R R; Rico, G; Giménez, J A

    2001-02-01

    The monocyte locomotion inhibitory factor (MLIF), a heat-stable oligopeptide found in the supernatant fluid of Entamoeba histolytica axenic cultures was isolated by ultra-filtration, gel-sieve chromatography and high powered liquid chromatography (HPLC), and its primary structure (Met-Gln-Cys-Asn-Ser) established by Edman sequencing and mass-spectrometry (MS). A synthetic peptide had the same selective anti-inflammatory features as the native material in comparable concentrations: in vitro inhibition of the locomotion in human peripheral blood monocytes, and of the respiratory burst in the same cells and in human neutrophil polymorphonuclear leucocytes; and in vivo depression of delayed hypersensitivity skin reactions to dinitrochlorobenzene in guinea pigs. This oligopeptide is apparently synthesized by the ameba as suggested by [(35)S]-Cys and Met incorporation, probably as part of a larger molecule, from which it is cleaved by proteolysis. The full sequence was not found in the 431 available E. histolytica protein sequences. The factor may contribute to the unexpected paucity of the late inflammatory reaction found in advanced invasive amebiasis and, perhaps in consequence, to the regeneration without scarring (restitutio ad integrum) of the affected organs that is observed following successful treatment of this disease

  2. Microbes and microbial toxins: paradigms for microbial-mucosal interactions. VI. Entamoeba histolytica: parasite-host interactions.

    Science.gov (United States)

    Stanley, S L; Reed, S L

    2001-06-01

    The protozoan intestinal parasite Entamoeba histolytica remains a significant cause of morbidity and mortality worldwide. E. histolytica causes two major clinical syndromes, amebic colitis and amebic liver abscess. Recent advances in the development of in vitro and in vivo models of disease, new genetic approaches, the identification of key E. histolytica virulence factors, and the recognition of crucial elements of the host response to infection have led to significant insights into the pathogenesis of amebic infection. E. histolytica virulence factors include 1) a surface galactose binding lectin that mediates E. histolytica binding to host cells and may contribute to amebic resistance to complement, 2) amebapores, small peptides capable of lysing cells, which may play a role in killing intestinal epithelial cells, hepatocytes, and host defense cells, and 3) a family of secreted cysteine proteinases that play a key role in E. histolytica tissue invasion, evasion of host defenses, and parasite induction of gut inflammation. Amebae can both lyse host cells and induce their suicide through programmed cell death. The host response is also an important factor in the outcome of infection, and neutrophils may play a key role in contributing to the tissue damage seen in amebiasis and in controlling amebic infection.

  3. Could the homologous sequence of anti-inflammatory pentapeptide (MLIF) produced by Entamoeba histolytica in the N protein of rabies virus affect the inflammatory process?

    Science.gov (United States)

    Morales, M E; Rico, G; Gómez, J L; Alonso, R; Cortés, R; Silva, R; Giménez, J A; Kretschmer, R; Aguilar-Setién, A

    2006-02-01

    Amebiasis and rabies are public health problems, and they have in common a poor inflammatory effect in the target organs that they affect. In the GenBank, it was found that the anti-inflammatory peptide monocyte locomotion inhibitory factor (MLIF) produced by Entamoeba histolytica homologates 80%, with a fragment of the N protein of the rabies virus. We speculated if the N protein could contribute to the scant inflammatory reaction produced by rabies virus in central nervous system. The N protein was obtained and studied in vitro and in vivo. The N protein, as MLIF, inhibited the respiratory burst in human mononuclear phagocytes (43%, p<0.05), but in contrast to MLIF, it increased chemotaxis and it did not significantly inhibit delayed hypersensitivity skin reaction to 1-chloro-2-4-dinitrobenzene in guinea pigs. Therefore, the full peptide sequence has to be present or it has to be cleaved-free from the large recombinant N protein molecule (55 kDa) to become active.

  4. Discrimination of Entamoeba moshkovskii in patients with gastrointestinal disorders by single-round PCR.

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    Nazemalhosseini Mojarad, Ehsan; Nochi, Zahra; Sahebekhtiari, Navid; Rostami Nejad, Mohammad; Dabiri, Hossein; Zali, Mohammad Reza; Kazemi, Bahram; Haghighi, Ali

    2010-03-01

    Entamoeba moshkovskii and Entamoeba dispar are impossible to differentiate microscopically from the pathogenic species Entamoeba histolytica. There are limited data on the prevalence of these commensal parasites in Iran. We utilized a single-round PCR assay to determine the prevalence of E. moshkovskii, E. dispar, and E. histolytica in stool samples from Iranian patients infected with gastrointestinal disorders. After culturing of microscopy-positive isolates and extraction of DNA, PCR was carried out to differentiate the Entamoeba isolates. Out of 3,825 stool samples examined by microscopy, 58 specimens (1.52%) were infected with E. histolytica, E. dispar, or E. moshkovskii. By PCR, 2 E. histolytica (3.45%), 53 E. dispar (91.37%), 2 E. moshkovskii (3.45%), and one mixed E. dispar/E. moshkovskii infection (1.73%) were detected. In view of the reporting of E. moshkovskii in this study in Iran and the difficulty in discriminating this ameba from two similar Entamoeba spp. by microscopy, we recommend the single-round PCR assay as an alternative tool in routine diagnosis and in epidemiological studies of amebiasis.

  5. Erythrophagocytosis in Entamoeba histolytica and Entamoeba dispar: A Comparative Study

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    Daniel Talamás-Lara

    2014-01-01

    Full Text Available Entamoeba histolytica is the causative agent of human intestinal and liver amebiasis. The extraordinary phagocytic activity of E. histolytica trophozoites has been accepted as one of the virulence mechanisms responsible for their invasive capacity. The recognition of the noninvasive Entamoeba dispar as a different species has raised the question as to whether the lack of pathogenic potential of this ameba correlates with a limited phagocytic capacity. We have therefore compared the process of erythrophagocytosis in both species by means of light and video microscopy, hemoglobin measurement, and the estimation of reactive oxygen species (ROS. In the present study, we confirmed that E. dispar has lower erythrophagocytic capacity. We also observed by video microscopy a new event of erythrocyte opsonization-like in both species, being more characteristic in E. histolytica. Moreover, E. dispar showed a lower capacity to produce ROS compared with the invasive species and also showed a large population of amoebae that did not engulf any erythrocyte over time. Our results demonstrate that E. histolytica has a higher phagocytic capacity than E. dispar, including a higher rate of production of ROS in the course of ingesting red blood cells.

  6. Amoebiasis vaccine development: A snapshot on E. histolytica with emphasis on perspectives of Gal/GalNAc lectin.

    Science.gov (United States)

    Singh, Ram Sarup; Walia, Amandeep Kaur; Kanwar, Jagat Rakesh; Kennedy, John F

    2016-10-01

    Amoebiasis/amebiasis is a gastrointestinal infection caused by an enteric dwelling protozoan, Entamoeba histolytica. The disease is endemic in the developing world and is transmitted mainly via the faecal-oral route (e.g., in water or food) and may or may not be symptomatic. This disease of socio-economic importance worldwide involves parasite adherence and cytolysis of human cells followed by invasion that is mediated by galactose-binding (Gal/GalNAc) surface lectin. Disruption of the mucus layer leads to invasive intestinal and extraintestinal infection. Gal-lectin based vaccinations have conferred protection in various animal models against E. histolytica infections. Keeping in view the pivotal role of Gal/GalNAc lectin in amoebiasis vaccine development, its regulation, genomic view of the parasite involving gene conversion in lectin gene families, current knowledge about involvement of Gal/GalNAc lectin in adherence, pathogenicity, signalling, encystment, generating host immune response, and in turn protozoa escape strategies, and finally its role as effective vaccine candidate has been described. This review will help researchers to explore pathogenesis mechanism along with genomic studies and will also provide a framework for future amoebiasis vaccine development studies.

  7. Effects of Cd+2, Cu+2, Ba+2 and Co+2 ions on Entamoeba histolytica cysts

    Institute of Scientific and Technical Information of China (English)

    Umit Aksoy; Sebnem Ustun; Hande Dagci; Suleyman Yazar

    2004-01-01

    AIM: The effects of cobalt, copper, cadmium and barium ions on the cysts of Entamoeba histolytica (E.histolytica),an amebic dysentery agent, cultured in Robinson medium were investigated.METHODS: E. histolytica cysts and trophozoites isolated from a patient with amebiasis were cultivated in the medium,incubated at 37 ℃ for a period of 4 days and 40x104/ml amebic cysts were then transferred to a fresh medium. At the second stage, 0.05, 0.1 and 0.2 mM of selected metal ions were added to the medium, and the effects of these ions on parasitic reproduction compared with the control group were observed.RESULTS: It was determined that the number of living parasites in all the groups containing metal ions decreased significantly rtarting from 30 minutes (P<0.01). CuCl2 showed the highest lethal effect on E.histolytita cysts, whereas the lowest lethal effect was observed with CoCl2. It was also seen that the number of living cells was decreased as the ion concentration and exposure time were increased, and that there were no living paasites in the medium at the end of 24 h (P<0.01).CONCLUSION: It may be stated that the effect of everincreasing contamination of the environment with metal waste materials on parasites should be investigated further.

  8. Fixed drug eruption due to metronidazole: a case report

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    Dr. Maxilline D. Marak

    2014-06-01

    Full Text Available Metronidazole is commonly used for the treatment of amebiasis, giardiasis and trichomonous vaginitis. Its side effects are relatively frequent and unpleasant, but nonserious. It has the potential to cause fixed drug eruption (FDE. Case Presentation: This 10 year male boy presented for the itching in some part of the body including an itchy, erythematous oval lesion over the right side of the lower part of anterior abdominal wall. He developed these problems after intake of metronidazole tablet. He was diagnosed to be a case of FDE due to metronidazole. This case of adverse drug reaction (ADR was “probable” type (Score=7 of reaction based on Naranjo ADR probability scale and severity assessment showed “mild” type (level 2 based on Hartwig et al scale. The offending drug was stopped immediately and managed with deflazacort tablet 12 mg for 10 days and Fusidic acid+Betamethasone cream for topical application. Discussion: FDE due to metronidazole usually occur within 30 min to 8 hours following its administration and mean length of time from drug intake to the onset of symptoms is approximately 2 hr. Tissue damage in FDE results from the preferential activation of intraepidermal CD8+T cells

  9. Proteomic identification of S-nitrosylated proteins in the parasite Entamoeba histolytica by resin-assisted capture: insights into the regulation of the Gal/GalNAc lectin by nitric oxide.

    Science.gov (United States)

    Hertz, Rivka; Ben Lulu, Shani; Shahi, Preeti; Trebicz-Geffen, Meirav; Benhar, Moran; Ankri, Serge

    2014-01-01

    Entamoeba histolytica is a gastrointestinal protozoan parasite that causes amebiasis, a disease which has a worldwide distribution with substantial morbidity and mortality. Nitrosative stress, which is generated by innate immune cells, is one of the various environmental challenges that E. histolytica encounters during its life cycle. Although the effects of nitric oxide (NO) on the regulation of gene expression in this parasite have been previously investigated, our knowledge on S-nitrosylated proteins in E.histolytica is lacking. In order to fill this knowledge gap, we performed a large-scale detection of S-nitrosylated (SNO) proteins in E.histolytica trophozoites that were treated with the NO donor, S-nitrosocysteine by resin-assisted capture (RAC). We found that proteins involved in glycolysis, gluconeogenesis, translation, protein transport, and adherence to target cells such as the heavy subunit of Gal/GalNac lectin are among the S-nitrosylated proteins that were enriched by SNO-RAC. We also found that the S-nitrosylated cysteine residues in the carbohydrate recognition domain (CRD) of Gal/GalNAc lectin impairs its function and contributes to the inhibition of E.histolytica adherence to host cells. Collectively, these results advance our understanding of the mechanism of reduced E.histolytica adherence to mammalian cells by NO and emphasize the importance of NO as a regulator of key physiological functions in E.histolytica.

  10. IN-VITRO STUDY OF ENTAMOEBA HISTOLYTICA WITH COCONUT JUICE ACT AS AN ANTIAMOEBIC AGENT AT DIFFERENT CONCENTRATION IN NIH MEDIUM

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    Shrivastava Bhanu

    2011-10-01

    Full Text Available Amoebiasis is a parasitic infection caused by Entamoeba histolytica. It is usually contracted by ingesting water or food contaminated with amoebic cysts. Amoebiasis is an intestinal infection that may or may not be symptomatic. When symptoms are present it is generally known as invasive amoebiasis. It is anaerobic parasitic protozoan, motile, commonly found in human intestine and it is also found in animals example like cat and goat but its definitive host is human beings. Its Infective stage is quadrinucleated cyst is called trophozoite. Invasive intestinal amebiasis is initiated with attachment of trophozite to the colonic mucous layer and it starts the mucous disruption and depletion. Mucous secret by fecal. Infection spread mainly by soiled hands, contaminated water and food or direct contact with carrier containing cysts of the protozoa. Man who has sex with man can also become infected. Approximately 50 million people have invasive disease resulting in 1, 00,000 death/year. After malaria it is the second severe disease because the parasite has a worldwide distribution so it is called worldwide disease. More than 10% of the population have been reported from various developing countries.

  11. Examination of genotoxic effects of fumagillin in vivo

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    Kulić Milan

    2009-01-01

    Full Text Available Fumagillin is an antibiotic derived from the fungus Aspergillus fumigatus. It has been used successfully for the treatment of intestinal microsporidiosis in HIV-positive humans, as well as in those suffering from intestinal amebiasis and microsporidial keratoconjunctivitis. In veterinary medicine it is approved for the treatment of microsporidiosis in bees and fish. In this research fumagillin was tested for the ability to provoke chromosomal aberrations in mouse bone marrow cells. BALB/c mice were administered fumagillin by gastric probe in doses of 5, 10 and 20 mg/kg b.w. Water-sugary syrup was the negative and cyclophosphamide (15 mg/kg b.w. the positive control. Significantly increased frequencies (p<0.01 or p<0.001 of numerical chromosomal aberrations (aneuploidies and poliploidies was observed both in the medium (10 mg/kg b.w. and the highest (20 mg/kg b.w. dose of fumagillin. Structural chromosomal aberrations (gaps, breaks and insertions were noticeably more frequent in comparison to negative control only in the highest experimental dose of dycikloheksilamine. These results clearly showed that fumagillin in concetrations 10 and 20 mg/kg b.w. had a genotoxic potential in vivo.

  12. Association between amebic liver abscess and Human Immunodeficiency Virus infection in Taiwanese subjects

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    Chen Mao-Yuan

    2008-04-01

    Full Text Available Abstract Purpose Invasive amebiasis is an emerging parasitic disorder in Taiwan, especially in patients diagnosed with human immunodeficiency virus (HIV infection. Thirty-three Taiwanese subjects with amebic liver abscess (ALA were examined and a possible correlation between ALA and HIV infection was investigated. Results Among ALA patients, the proportion of HIV-positive individuals increased during the study period. ALA was the first major clinical presentation in 54% of HIV patients with ALA. Overall, 58% (14/24 of HIV-infected patients had a CD4+ count > 200 cells/μL and 82.1% (23/28 had no concurrent opportunistic infection or other evidence of HIV infection. There was no marked difference in clinical characteristics between HIV-positive and HIV-negative ALA patients except the level of leukocytosis. Conclusion While the clinical characteristics described herein cannot be used to determine whether ALA patients have HIV infection, routine HIV testing is recommended in patients with ALA, even in the absence of HIV symptoms.

  13. Sensibilidad de trofozoítos de Entamoeba histolytica a ivermectina Sensibility of Entamoeba histolytica trophozoites to ivermectin

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    Francisco González-Salazar

    2009-06-01

    Full Text Available La amibiasis producida por Entamoeba histolytica es un problema de salud pública. Las formas clínicas más frecuentes son la disentería y el absceso hepático amibiano. En el mundo se notifican anualmente 50 millones de casos y más de 100 000 muertes por esta enfermedad. El ciclo de vida de E. histolytica tiene dos fases: trofozoíto y quiste. Los trofozoítos son los responsables de producir enfermedad. El tratamiento actual para la amibiasis incluye medicamentos con efectos colaterales serios. La ivermectina es un macrólido con actividad contra endoparásitos y ectoparásitos causantes de strongiloidosis, filariasis, oncocercosis, sarna y pediculosis. Su uso está extendido a casi todo el mundo y se lo reconoce como un medicamento seguro. El objetivo de este trabajo fue determinar la sensiblidad in vitro de trofozoítos de E. histolytica al tratamiento con ivermectina. Para determinar su sensibilidad a la droga, se utilizaron trofozoítos de E. histolytica cultivados en medio PEHPS. Durante su fase de crecimiento logarítmico se expusieron a diferentes concentraciones de ivermectina. Como controles se usaron otras drogas antiparasitarias. Se prepararon diluciones seriadas de cada droga, luego se agregaron a tubos con parásitos (2 x 10(4 células/ml. Se incubó por 72 h y luego se determinó el porcentaje de inhibición de crecimiento calculado por análisis Probit. La ivermectina tiene actividad contra trofozoítos de E. histolytica. La dosis de ivermectina que produjo el 50% de inhibición de crecimiento fue de 6.40 mg/ml. Esta dosis fue mayor a la encontrada con otras drogas antiparasitarias. Falta demostrar su actividad in vivo en modelos animales.Amebiasis caused by Entamoeba histolytica is a problem of public world health. The most frequent clinical presentation are the dysentery and the amebic liver abscess. Fifty millions of cases and more than 100.000 deaths for this disease are reported annually worldwide. The life cycle of E

  14. IMPORTANT PROTOZOAN PARASITES IN INDONESIA

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    Srisasi Gandahusada

    2012-09-01

    anomalies are found. T. gondii as one of the causes, is widely spread in man and animals. The prevalence of Toxoplasma antibodies in man varies from 2 % to 63 %, in cats and other animals it can reach up to 75%. Confirmed cases of congenital toxoplasmosis are reported. The diagnosis of toxoplasmosis in the Department of Parasitology, University of Indonesia is done with detection of specific IgM and IgG antibodies with ELISA. A test for antigenemia to get a rapid and direct diagnosis of active infection is not yet available. A suitable Toxoplasma vaccine to prevent toxoplasmosis would be desirable. E. histolytica infection is endemic throughout the archipelago. The prevalence rates are 18% to 25% . Extraintestinal infection mostly occurs in the liver. Pulmonary amebiasis is occasionally found. Medication with metronidazole has obtained good results. Diagnosis of extraintestinal amebiasis in our laboratory is by the immunodiffusion test, which is not capable to differentiate active infection from infection in the past. A more accurate diagnosis would be the use of monoclonal antibodies to detect antigens.

  15. Water-soluble ruthenium complexes bearing activity against protozoan parasites.

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    Sarniguet, Cynthia; Toloza, Jeannette; Cipriani, Micaella; Lapier, Michel; Vieites, Marisol; Toledano-Magaña, Yanis; García-Ramos, Juan Carlos; Ruiz-Azuara, Lena; Moreno, Virtudes; Maya, Juan Diego; Azar, Claudio Olea; Gambino, Dinorah; Otero, Lucía

    2014-06-01

    Parasitic illnesses are major causes of human disease and misery worldwide. Among them, both amebiasis and Chagas disease, caused by the protozoan parasites, Entamoeba histolytica and Trypanosoma cruzi, are responsible for thousands of annual deaths. The lack of safe and effective chemotherapy and/or the appearance of current drug resistance make the development of novel pharmacological tools for their treatment relevant. In this sense, within the framework of the medicinal inorganic chemistry, metal-based drugs appear to be a good alternative to find a pharmacological answer to parasitic diseases. In this work, novel ruthenium complexes [RuCl2(HL)(HPTA)2]Cl2 with HL=bioactive 5-nitrofuryl containing thiosemicarbazones and PTA=1,3,5-triaza-7-phosphaadamantane have been synthesized and fully characterized. PTA was included as co-ligand in order to modulate complexes aqueous solubility. In fact, obtained complexes were water soluble. Their activity against T. cruzi and E. histolytica was evaluated in vitro. [RuCl2(HL4)(HPTA)2]Cl2 complex, with HL4=N-phenyl-5-nitrofuryl-thiosemicarbazone, was the most active compound against both parasites. In particular, it showed an excellent activity against E. histolytica (half maximal inhibitory concentration (IC50)=5.2 μM), even higher than that of the reference drug metronidazole. In addition, this complex turns out to be selective for E. histolytica (selectivity index (SI)>38). The potential mechanism of antiparasitic action of the obtained ruthenium complexes could involve oxidative stress for both parasites. Additionally, complexes could interact with DNA as second potential target by an intercalative-like mode. Obtained results could be considered a contribution in the search for metal compounds that could be active against multiple parasites.

  16. Conjugation of metronidazole with dextran: a potential pharmaceutical strategy to control colonic distribution of the anti-amebic drug susceptible to metabolism by colonic microbes

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    Kim, Wooseong; Yang, Yejin; Kim, Dohoon; Jeong, Seongkeun; Yoo, Jin-Wook; Yoon, Jeong-Hyun; Jung, Yunjin

    2017-01-01

    Metronidazole (MTDZ), the drug of choice for the treatment of protozoal infections such as luminal amebiasis, is highly susceptible to colonic metabolism, which may hinder its conversion from a colon-specific prodrug to an effective anti-amebic agent targeting the entire large intestine. Thus, in an attempt to control the colonic distribution of the drug, a polymeric colon-specific prodrug, MTDZ conjugated to dextran via a succinate linker (Dex-SA-MTDZ), was designed. Upon treatment with dextranase for 8 h, the degree of Dex-SA-MTDZ depolymerization (%) with a degree of substitution (mg of MTDZ bound in 100 mg of Dex-SA-MTDZ) of 7, 17, and 30 was 72, 38, and 8, respectively, while that of dextran was 85. Depolymerization of Dex-SA-MTDZ was found to be necessary for the release of MTDZ, because dextranase pretreatment ensures that de-esterification occurs between MTDZ and the dextran backbone. In parallel, Dex-SA-MTDZ with a degree of substitution of 17 was found not to release MTDZ upon incubation with the contents of the small intestine and stomach of rats, but it released MTDZ when incubated with rat cecal contents (including microbial dextranases). Moreover, Dex-SA-MTDZ exhibited prolonged release of MTDZ, which contrasts with drug release by small molecular colon-specific prodrugs, MTDZ sulfate and N-nicotinoyl-2-{2-(2-methyl-5-nitroimidazol-1-yl)ethyloxy}-d,l-glycine. These prodrugs were eliminated very rapidly, and no MTDZ was detected in the cecal contents. Consistent with these in vitro results, we found that oral gavage of Dex-SA-MTDZ delivered MTDZ (as MTDZ conjugated to [depolymerized] dextran) to the distal colon. However, upon oral gavage of the small molecular prodrugs, no prodrugs were detected in the distal colon. Collectively, these data suggest that dextran conjugation is a potential pharmaceutical strategy to control the colonic distribution of drugs susceptible to colonic microbial metabolism. PMID:28243064

  17. Analysis of parasitic diseases diagnosed by tissue biopsy specimens at KyungHee Medical Center (1984-2005) in Seoul, Korea.

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    Choi, Won-Hyung; Chu, Jong-Phil; Jiang, Meihua; Lee, Yun-Sik; Kim, Bum-Shik; Kim, Deog-Gon; Park, Yong-Koo

    2010-03-01

    We analyzed parasitic diseases diagnosed by tissue biopsy specimens at KyungHee Medical Center (KMC) from 1984 to 2005. The total number of parasite infection cases was 150 (0.07%) out of the total 211,859 biopsy specimens submitted for histopathological examinations. They consisted of 62 cysticercosis, 23 sparganosis, 16 paragonimiasis, 15 amebiasis, 11 anisakiasis, 11 clonorchiasis, 3 ascariasis, 2 scabies, 2 enterobiasis, 2 trichuriasis, 1 leishmaniasis, 1 taeniasis, and 1 thelaziasis. Out of 62 cysticercosis cases, 55 were detected in subcutaneous tissues or the central nerve system. Eighteen out of 23 sparganosis cases were involved in muscular and subcutaneous tissues. In most anisakiasis cases, the involved organ was the stomach. The lung and the pleura were the most common site of paragonimiasis. The incidence of parasitic diseases during the first 5 years (1984-1988) was the highest of all observed periods. After 1989, similar incidences were shown throughout the period. Whereas cysticercosis was diagnosed in 34 cases during 1984-1988, no case has been diagnosed since 2000. In the case of sparganosis, the chronological incidence was almost uniform throughout the period 1984-2005. Paragonimiasis showed a similar tendency to cysticercosis. In gender and age distribution of parasitic diseases, men showed higher incidence rates than females, and the age groups of the 40s or older indicated higher infection frequencies than other age groups. Therefore, these results are a significant report to appear the tendency of human parasitic disease diagnosed by tissue biopsy in association with parasitosis at KMC in Seoul.

  18. Immunization with the Entamoeba histolytica surface metalloprotease EhMSP-1 protects hamsters from amebic liver abscess.

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    Roncolato, Eduardo C; Teixeira, José E; Barbosa, José E; Zambelli Ramalho, Leandra N; Huston, Christopher D

    2015-02-01

    Diarrhea and amebic liver abscesses due to invasive Entamoeba histolytica infections are an important cause of morbidity and mortality in the developing world. Entamoeba histolytica adherence and cell migration, two phenotypes linked to virulence, are both aberrant in trophozoites deficient in the metallosurface protease EhMSP-1, which is a homologue of the Leishmania vaccine candidate leishmanolysin (GP63). We examined the potential of EhMSP-1 for use as a vaccine antigen to protect against amebic liver abscesses. First, existing serum samples from South Africans naturally infected with E. histolytica were examined by enzyme-linked immunosorbent assay (ELISA) for the presence of EhMSP-1-specific IgG. Nine of 12 (75%) people with anti-E. histolytica IgG also had EhMSP-1-specific IgG antibodies. We next used a hamster model of amebic liver abscess to determine the effect of immunization with a mixture of four recombinant EhMSP-1 protein fragments. EhMSP-1 immunization stimulated a robust IgG antibody response. Furthermore, EhMSP-1 immunization of hamsters reduced development of severe amebic liver abscesses following intrahepatic injection of E. histolytica by a combined rate of 68% in two independent animal experiments. Purified IgG from immunized compared to control animals bound to the surface of E. histolytica trophozoites and accelerated amebic lysis via activation of the classical complement cascade. We concluded that EhMSP-1 is a promising antigen that warrants further study to determine its full potential as a target for therapy and/or prevention of invasive amebiasis.

  19. Crystal Structure Analysis of Wild Type and Fast Hydrolyzing Mutant of EhRabX3, a Tandem Ras Superfamily GTPase from Entamoeba histolytica.

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    Srivastava, Vijay Kumar; Chandra, Mintu; Saito-Nakano, Yumiko; Nozaki, Tomoyoshi; Datta, Sunando

    2016-01-16

    The enteric protozoan parasite, Entamoeba histolytica, is the causative agent of amoebic dysentery, liver abscess and colitis in human. Vesicular trafficking plays a key role in the survival and virulence of the protozoan and is regulated by various Rab GTPases. EhRabX3 is a catalytically inefficient amoebic Rab protein, which is unique among the eukaryotic Ras superfamily by virtue of its tandem domain organization. Here, we report the crystal structures of GDP-bound fast hydrolyzing mutant (V71A/K73Q) and GTP-bound wild type EhRabX3 at 3.1 and 2.8Å resolutions, respectively. Though both G-domains possess "phosphate binding loop containing nucleoside triphosphate hydrolases fold", only the N-terminal domain binds to guanine nucleotide. The relative orientation of the N-terminal domain and C-terminal domain is stabilized by numerous inter-domain interactions. Compared to other Ras superfamily members, both the GTPase domains displayed large deviation in switch II perhaps due to non-conservative substitutions in this region. As a result, entire switch II is restructured and moved away from the nucleotide binding pocket, providing a rationale for the diminished GTPase activity of EhRabX3. The N-terminal GTPase domain possesses unusually large number of cysteine residues. X-ray crystal structure of the fast hydrolyzing mutant of EhRabX3 revealed that C39 and C163 formed an intra-molecular disulfide bond. Subsequent mutational and biochemical studies suggest that C39 and C163 are critical for maintaining the structural integrity and function of EhRabX3. Structure-guided functional investigation of cysteine mutants could provide the physiological implications of the disulfide bond and could allow us to design potential inhibitors for the better treatment of intestinal amebiasis.

  20. Knockdown of Five Genes Encoding Uncharacterized Proteins Inhibits Entamoeba histolytica Phagocytosis of Dead Host Cells.

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    Sateriale, Adam; Miller, Peter; Huston, Christopher D

    2016-04-01

    Entamoeba histolytica is the protozoan parasite that causes invasive amebiasis, which is endemic to many developing countries and characterized by dysentery and liver abscesses. The virulence of E. histolytica correlates with the degree of host cell engulfment, or phagocytosis, and E. histolytica phagocytosis alters amebic gene expression in a feed-forward manner that results in an increased phagocytic ability. Here, we used a streamlined RNA interference screen to silence the expression of 15 genes whose expression was upregulated in phagocytic E. histolytica trophozoites to determine whether these genes actually function in the phagocytic process. When five of these genes were silenced, amebic strains with significant decreases in the ability to phagocytose apoptotic host cells were produced. Phagocytosis of live host cells, however, was largely unchanged, and the defects were surprisingly specific for phagocytosis. Two of the five encoded proteins, which we named E. histolytica ILWEQ (EhILWEQ) and E. histolytica BAR (EhBAR), were chosen for localization via SNAP tag labeling and localized to the site of partially formed phagosomes. Therefore, both EhILWEQ and EhBAR appear to contribute to E. histolytica virulence through their function in phagocytosis, and the large proportion (5/15 [33%]) of gene-silenced strains with a reduced ability to phagocytose host cells validates the previously published microarray data set demonstrating feed-forward control of E. histolytica phagocytosis. Finally, although only limited conclusions can be drawn from studies using the virulence-deficient G3 Entamoeba strain, the relative specificity of the defects induced for phagocytosis of apoptotic cells but not healthy cells suggests that cell killing may play a rate-limiting role in the process of Entamoeba histolytica host cell engulfment.

  1. X-ray structures of thioredoxin and thioredoxin reductase from Entamoeba histolytica and prevailing hypothesis of the mechanism of Auranofin action.

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    Parsonage, Derek; Sheng, Fang; Hirata, Ken; Debnath, Anjan; McKerrow, James H; Reed, Sharon L; Abagyan, Ruben; Poole, Leslie B; Podust, Larissa M

    2016-05-01

    The anti-arthritic gold-containing drug Auranofin is lethal to the protozoan intestinal parasite Entamoeba histolytica, the causative agent of human amebiasis, in both culture and animal models of the disease. A putative mechanism of Auranofin action proposes that monovalent gold, Au(I), released from the drug, can bind to the redox-active dithiol group of thioredoxin reductase (TrxR). Au(I) binding in the active site is expected to prevent electron transfer to the downstream substrate thioredoxin (Trx), thus interfering with redox homeostasis in the parasite. To clarify the molecular mechanism of Auranofin action in more detail, we determined a series of atomic resolution X-ray structures for E. histolytica thioredoxin (EhTrx) and thioredoxin reductase (EhTrxR), the latter with and without Auranofin. Only the disulfide-bonded form of the active site dithiol (Cys(140)-Cys(143)) was invariably observed in crystals of EhTrxR in spite of the addition of reductants in various crystallization trials, and no gold was found associated with these cysteines. Non-catalytic Cys(286) was identified as the only site of modification, but further mutagenesis studies using the C286Q mutant demonstrated that this site was not responsible for inhibition of EhTrxR by Auranofin. Interestingly, we obtained both of the catalytically-relevant conformations of this bacterial-like, low molecular weight TrxR in crystals without requiring an engineered disulfide linkage between Cys mutants of TrxR and Trx (as was originally done with Escherichia coli TrxR and Trx). We note that the -CXXC- catalytic motif, even if reduced, would likely not provide space sufficient to bind Au(I) by both cysteines of the dithiol group.

  2. Resistance to intestinal Entamoeba histolytica infection is conferred by innate immunity and Gr-1+ cells.

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    Asgharpour, Amon; Gilchrist, Carol; Baba, Duza; Hamano, Shinjiro; Houpt, Eric

    2005-08-01

    Establishment of intestinal infection with Entamoeba histolytica depends on the mouse strain; C57BL/6 mice are highly resistant, and C3H/HeJ mice are relatively susceptible. We found that resistance to intestinal infection was independent of lymphocyte activity or H-2 haplotype and occurred in the first hours to days postchallenge according to in vivo imaging. At 18 h postchallenge, the ceca of resistant C57BL/6 mice were histologically unremarkable, in contrast to the severe inflammation observed in susceptible C3H/HeJ mice. Comparison of cecal gene expression in C3H/HeJ and C57BL/6 mice demonstrated that there was parasite-induced upregulation of proinflammatory and neutrophil chemotaxis transcripts and there was downregulation of transforming growth factor beta signaling molecules. Pretreatment with dexamethasone abrogated the partial resistance of C3H/HeJ or CBA mice through an innate, lymphocyte-independent mechanism, but it had no effect on the high-level resistance of C57BL/6 mice. Similarly, administration of a neutrophil-depleting anti-Gr-1 monoclonal antibody (RB6-8C5) decreased the partial resistance of CBA mice and led to severe pathology compared to control antibody-treated mice, but it had no effect on C57BL/6 resistance. These data indicate that there are discrete mechanisms of innate resistance to E. histolytica depending on the host background and, in contrast to other reports, imply that neutrophils are protective and not damaging in intestinal amebiasis.

  3. Entamoeba histolytica cysteine proteinase 5 binds integrin on colonic cells and stimulates NFkappaB-mediated pro-inflammatory responses.

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    Hou, Yongzhong; Mortimer, Leanne; Chadee, Kris

    2010-11-12

    Integrins are important mammalian receptors involved in normal cellular functions and the pathogenesis of inflammation and disease. Entamoeba histolytica is a protozoan parasite that colonizes the gut, and in 10% of infected individuals, causes amebic colitis and liver abscess resulting in 10(5) deaths/year. E. histolytica-induced host inflammatory responses are critical in the pathogenesis of the disease, yet the host and parasite factors involved in disease are poorly defined. Here we show that pro-mature cysteine proteinase 5 (PCP5), a major virulent factor that is abundantly secreted and/or present on the surface of ameba, binds via its RGD motif to α(V)β(3) integrin on Caco-2 colonic cells and stimulates NFκB-mediated pro-inflammatory responses. PCP5 RGD binding to α(V)β(3) integrin triggered integrin-linked kinase(ILK)-mediated phosphorylation of Akt-473 that bound and induced the ubiquitination of NF-κB essential modulator (NEMO). As NEMO is required for activation of the IKKα-IKKβ complex and NFκB signaling, these events markedly up-regulated pro-inflammatory mediator expressions in vitro in Caco-2 cells and in vivo in colonic loop studies in wild-type and Muc2(-/-) mice lacking an intact protective mucus barrier. These results have revealed that EhPCP5 RGD motif is a ligand for α(V)β(3) integrin-mediated adhesion on colonic cells and represents a novel mechanism that E. histolytica trophozoites use to trigger an inflammatory response in the pathogenesis of intestinal amebiasis.

  4. Transcriptome analysis of encystation in Entamoeba invadens.

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    De Cádiz, Aleyla Escueta; Jeelani, Ghulam; Nakada-Tsukui, Kumiko; Caler, Elisabet; Nozaki, Tomoyoshi

    2013-01-01

    Encystation is an essential differentiation process for the completion of the life cycle of a group of intestinal protozoa including Entamoeba histolytica, the causative agent of intestinal and extraintestinal amebiasis. However, regulation of gene expression during encystation is poorly understood. To comprehensively understand the process at the molecular level, the transcriptomic profiles of E. invadens, which is a related reptilian species that causes an invasive disease similar to that of E. histolytica, was investigated during encystation. Using a custom-generated Affymetrix platform microarray, we performed time course (0.5, 2, 8, 24, 48, and 120 h) gene expression analysis of encysting E. invadens. ANOVA analysis revealed that a total of 1,528 genes showed ≥3 fold up-regulation at one or more time points, relative to the trophozoite stage. Of these modulated genes, 8% (116 genes) were up-regulated at the early time points (0.5, 2 and 8h), while 63% (962 genes) were up-regulated at the later time points (24, 48, and 120 h). Twenty nine percent (450 genes) are either up-regulated at 2 to 5 time points or constitutively up-regulated in both early and late stages. Among the up-regulated genes are the genes encoding transporters, cytoskeletal proteins, proteins involved in vesicular trafficking (small GTPases), Myb transcription factors, cysteine proteases, components of the proteasome, and enzymes for chitin biosynthesis. This study represents the first kinetic analysis of gene expression during differentiation from the invasive trophozoite to the dormant, infective cyst stage in Entamoeba. Functional analysis on individual genes and their encoded products that are modulated during encystation may lead to the discovery of targets for the development of new chemotherapeutics that interfere with stage conversion of the parasite.

  5. Nitroimidazole carboxamides as antiparasitic agents targeting Giardia lamblia, Entamoeba histolytica and Trichomonas vaginalis.

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    Jarrad, A M; Debnath, A; Miyamoto, Y; Hansford, K A; Pelingon, R; Butler, M S; Bains, T; Karoli, T; Blaskovich, M A T; Eckmann, L; Cooper, M A

    2016-09-14

    Diarrhoeal diseases caused by the intestinal parasites Giardia lamblia and Entamoeba histolytica constitute a major global health burden. Nitroimidazoles are first-line drugs for the treatment of giardiasis and amebiasis, with metronidazole 1 being the most commonly used drug worldwide. However, treatment failures in giardiasis occur in up to 20% of cases and development of resistance to metronidazole is of concern. We have re-examined 'old' nitroimidazoles as a foundation for the systematic development of next-generation derivatives. Using this approach, derivatisation of the nitroimidazole carboxamide scaffold provided improved antiparasitic agents. Thirty-three novel nitroimidazole carboxamides were synthesised and evaluated for activity against G. lamblia and E. histolytica. Several of the new compounds exhibited potent activity against G. lamblia strains, including metronidazole-resistant strains of G. lamblia (EC50 = 0.1-2.5 μM cf. metronidazole EC50 = 6.1-18 μM). Other compounds showed improved activity against E. histolytica (EC50 = 1.7-5.1 μM cf. metronidazole EC50 = 5.0 μM), potent activity against Trichomonas vaginalis (EC50 = 0.6-1.4 μM cf. metronidazole EC50 = 0.8 μM) and moderate activity against the intestinal bacterial pathogen Clostridium difficile (0.5-2 μg/mL, cf. metronidazole = 0.5 μg/mL). The new compounds had low toxicity against mammalian kidney and liver cells (CC50 > 100 μM), and selected antiparasitic hits were assessed for human plasma protein binding and metabolic stability in liver microsomes to demonstrate their therapeutic potential.

  6. Prevalence of Entamoeba histolytica, Giardia lamblia, and Cryptosporidium spp. in Libya: 2000–2015

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    Ghenghesh, Khalifa Sifaw; Ghanghish, Khaled; BenDarif, Elloulu T.; Shembesh, Khaled; Franka, Ezzadin

    2016-01-01

    Introduction The intestinal protozoa Entamoeba histolytica, Giardia lamblia, and Cryptosporidium spp. are the causative agents of giardiasis, amebiasis, and cryptosporidiosis, respectively. Adequate knowledge of the geographical distribution of parasites and the demographic variables that influence their prevalence is important for effective control of infection in at-risk populations. Methods The data were obtained by an English language literature search of Medline and PubMed for papers using the search terms ‘intestinal parasites and Libya, G. lamblia and Libya, E. histolytica and Libya and Cryptosporidium and Libya’ for the period 2000–2015. Results The data obtained for the period 2000–2015 showed prevalence rates of 0.8–36.6% (mean 19.9%) for E. histolytica/dispar, 1.2–18.2% (mean 4.6%) for G. lamblia and 0.9–13% (mean 3.4%) for Cryptosporidium spp. among individuals in Libya with gastroenteritis (GE). On the other hand, prevalence rates of 0.8–16.3% (mean 8.3%), 1.8–28.8% (mean 4.8%), and 1.0–2.5% (mean=2.4), respectively, were observed for individuals without GE. The mean prevalence rate of E. histolytica/dispar was significantly higher among individuals with GE compared with those without GE (phistolytica, G. lamblia, and Cryptosporidium spp. may play a minor role in GE in Libya. The observed high prevalence rates of E. histolytica/dispar reported from Libya could be due mainly to the non-pathogenic E. dispar and E. moshkovskii. However, more studies are needed in the future using E. histolytica-specific enzyme immunoassays and/or molecular methods to confirm this observation. PMID:27363524

  7. Control of Entamoeba histolytica adherence involves metallosurface protease 1, an M8 family surface metalloprotease with homology to leishmanolysin.

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    Teixeira, Jose E; Sateriale, Adam; Bessoff, Kovi E; Huston, Christopher D

    2012-06-01

    Invasive amebiasis due to Entamoeba histolytica infection is an important cause of morbidity in developing countries. The E. histolytica genome contains two homologues to the metalloprotease leishmanolysin gene, Entamoeba histolytica MSP-1 (EhMSP-1) and EhMSP-2, while the commensal ameba Entamoeba dispar has lost EhMSP-1. In this study, we sought to characterize E. histolytica metallosurface protease 1 (EhMSP-1). Using immunoprecipitation and a model substrate, we found that EhMSP-1 was a functional metalloprotease. Confocal microscopy and flow cytometry revealed that EhMSP-1 localized to the cell surface and revealed the existence of distinct, nonclonal trophozoite populations with high and low EhMSP-1 surface abundance that became synchronized following serum starvation. Phenotypic assays were performed after silencing EhMSP-1. Adherence of EhMSP-1-deficient trophozoites to tissue culture cell monolayers was more than five times greater than that of control amebas, but surface staining of several antigens, including the galactose adherence lectin, was unchanged. EhMSP-1 silencing similarly increased adherence to both viable and apoptotic Jurkat lymphocytes. Tissue culture cell monolayer destruction was reduced by EhMSP-1 silencing, although it was blocked almost completely by inhibiting cysteine proteases. Consistent with a primary defect in regulation of amebic adherence, EhMSP-1 silencing also resulted in reduced mobility on tissue culture cell monolayers and in increased phagocytosis. In conclusion, EhMSP-1 was shown to be a surface metalloprotease involved in regulation of amebic adherence, with additional effects on cell motility, cell monolayer destruction, and phagocytosis.

  8. Identification and characterization of microRNAs from Entamoeba histolytica HM1-IMSS.

    Directory of Open Access Journals (Sweden)

    Fermín Mar-Aguilar

    Full Text Available BACKGROUND: Entamoeba histolytica is the causative agent of amebiasis, a disease that is a major source of morbidity and mortality in the developing world. MicroRNAs (miRNAs are a large group of non-coding RNAs that play important roles in regulating gene expression and protein translation in animals. Genome-wide identification of miRNAs is a critical step to facilitating our understanding of genome organization, genome biology, evolution, and post-transcriptional regulation. METHODOLOGY/PRINCIPAL FINDINGS: We sequenced a small RNA library prepared from a culture of trophozoites of Entamoeba histolytica Strain HM1-IMSS using a deep DNA sequencing approach. Deep sequencing yielded 16 million high-quality short sequence reads containing a total of 5 million non-redundant sequence reads. Based on a bioinformatics pipeline, we found that only 0.5% of these non-redundant small RNA reads were a perfect match with the drafted E. histolytica genome. We did not find miRNA homologs in plant or animal miRNAs. We discovered 199 new potential Entamoeba histolytica miRNAs. The expression and sequence of these Ehi-miRNAs were further validated through microarray by µParaflo Microfluidic Biochip Technology. Ten potential miRNAs were additionally confirmed by real time RT-PCR analysis. Prediction of target genes matched 32 known genes and 34 hypothetical genes. CONCLUSIONS/SIGNIFICANCE: These results show that there is a number of regulatory miRNAs in Entamoeba histolytica. The collection of miRNAs in this parasite could be used as a new platform to study genomic structure, gene regulation and networks, development, and host-parasite interactions.

  9. Participación del óxido nítrico durante el desarrollo del absceso hepático amebiano Nitric oxide participation during amoebic liver abscess development

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    Joel Ramírez-Emiliano

    2007-04-01

    Full Text Available El óxido nítrico participa en funciones fisiológicas y fisiopatológicas, así como en el mecanismo de defensa del sistema inmunológico de mamíferos contra parásitos, virus y bacterias. La Entamoeba histolytica es un parásito protozoario causante de la amebiasis, la cual se caracteriza por el daño intestinal y la formación del absceso hepático amebiano (AHA. El desarrollo del absceso hepático amebiano en el hámster es similar al que desarrolla el humano, mientras que el ratón es resistente a la formación de este absceso, debido a un incremento en la producción de óxido nítrico. A diferencia del ratón, el desarrollo del absceso hepático amebiano en el hámster es debido a un exceso en la producción de óxido nítrico o posiblemente a una mayor susceptibilidad del hámster al daño producido por el óxido nítrico. Por lo tanto, sería importante realizar más estudios para determinar si en el humano, un exceso en la producción de óxido nítrico favorece la formación del absceso hepático amebiano.Nitric oxide participates in both physiological and pathophysiological functions, and it plays an important role in the mammalian immune system in killing or inhibiting the growth of many pathogens, including parasites, viruses and bacteria. Entamoeba histolytica is a protozoan parasite that causes amoebiasis, which is characterized by intestinal damage and amoebic liver abscess development. The development of amoebic liver abscess in hamsters is similar to that in humans, whereas mice are resistant to amoebic liver abscess development due to an increase in nitric oxide production. Unlike in mice, amoebic liver abscess development in hamsters is due to an excess in nitric oxide production or possibly to a greater susceptibility of the hamster to damage caused by nitric oxide. Therefore, it could be important to elucidate if, in humans, an excess in nitric oxide production favors amoebic liver abscess development.

  10. Five prevalent antiprotozoal herbal drugs

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    Mohammad Azadbakht1

    2008-01-01

    Full Text Available , (Received 21 Jun, 2008 ; Accepted 12 Nov, 2008 AbstractAccording to the statistics provided by the World Health Organization (WHO, about 80% of the world population nowadays uses herbal drugs for treatment of diseases. Natural products obtained from medicinal plants, serve as a great source for drug production and are the main basis of new drug compounds. Unicellular organisms (Protozoa are the cause of deaths and spread of diseases in various societies, especially in developing countries. There are anti-malaria herbal dugs produced from various medicinal plants, some of which are used for treatment of the disease and some under study. The first anti-malaria drug was quinine, produced from bark of the Cinchona tree. Recently, the drug artemisinin has been introduced by Chinese scientists for the treatment of malaria and is currently used extensively. Coetaneous leishmaniosis (salak is one of the endemic diseases in most parts of Iran. Common drugs used against leishmaniosis (such as glucantim, have severe side-effects and in 10 to 25% of cases, there is a recurrence of the disease. Emetine is one of the drugs obtained from a root of the plant Ipecac, which is used for treatment of the disease sub-cutaneously. Giardiasis is an acute protozoan infection usually with no clinical symptoms, however, may appear as acute or chronic diarrhea. According to the announcement of WHO, more than 2/3 of the world’s population is infected with intestinal parasites and the prevalence of giardia is higher than other intestinal parasites. Herbal drugs, such as wild garlic, eucalyptus and thyme, are some of the major plants which can annihilate the giarda cysts. Annually, 75000 to 100000 people die of amebiasis (dysentery worldwide. Due to the motility of the organism, it causes sever pathological changes and sometimes colon ulcers, and if entered into the blood stream, it may appear as liver or brain abscess. Medicinal plants such as ipecac, mango, and papaya

  11. Prevalent HLA Class II Alleles in Mexico City Appear to Confer Resistance to the Development of Amebic Liver Abscess

    Science.gov (United States)

    Hernández, Eric G.; Granados, Julio; Partida-Rodríguez, Oswaldo; Valenzuela, Olivia; Rascón, Edgar; Magaña, Ulises; Escamilla-Tilch, Mónica; López-Reyes, Alberto; Nieves-Ramírez, Miriam; González, Enrique; Morán, Patricia; Rojas, Liliana; Valadez, Alicia; Luna, Alexandra; Estrada, Francisco J.; Maldonado, Carmen; Ximénez, Cecilia

    2015-01-01

    Amebiasis is an endemic disease and a public health problem throughout Mexico, although the incidence rates of amebic liver abscess (ALA) vary among the geographic regions of the country. Notably, incidence rates are high in the northwestern states (especially Sonora with a rate of 12.57/100,000 inhabitants) compared with the central region (Mexico City with a rate of 0.69/100,000 inhabitants). These data may be related to host genetic factors that are partially responsible for resistance or susceptibility. Therefore, we studied the association of the HLA-DRB1 and HLA-DQB1 alleles with resistance or susceptibility to ALA in two Mexican populations, one each from Mexico City and Sonora. Ninety ALA patients were clinically diagnosed by serology and sonography. Genomic DNA was extracted from peripheral blood mononuclear cells. To establish the genetic identity of both populations, 15 short tandem repeats (STRs) were analyzed with multiplexed PCR, and the allelic frequencies of HLA were studied by PCR-SSO using LUMINEX technology. The allele frequencies obtained were compared to an ethnically matched healthy control group (146 individuals). We observed that both affected populations differed genetically from the control group. We also found interesting trends in the population from Mexico City. HLA-DQB1*02 allele frequencies were higher in ALA patients compared to the control group (0.127 vs 0.047; p= 0.01; pc= NS; OR= 2.9, 95% CI= 1.09-8.3). The less frequent alleles in ALA patients were HLA-DRB1*08 (0.118 vs 0.238 in controls; p= 0.01; pc= NS; OR= 0.42, 95% CI= 0.19-0.87) and HLA-DQB1*04 (0.109 vs 0.214; p= 0.02; pc= NS; OR= 0.40, 95% CI= 0.20-0.94). The haplotype HLA-DRB1*08/-DQB1*04 also demonstrated a protective trend against the development of this disease (0.081 vs. 0.178; p=0.02; pc=NS; OR= 0.40, 95% CI= 0.16-0.93). These trends suggest that the prevalent alleles in the population of Mexico City may be associated with protection against the development of ALA

  12. Prevalent HLA Class II Alleles in Mexico City Appear to Confer Resistance to the Development of Amebic Liver Abscess.

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    Eric G Hernández

    Full Text Available Amebiasis is an endemic disease and a public health problem throughout Mexico, although the incidence rates of amebic liver abscess (ALA vary among the geographic regions of the country. Notably, incidence rates are high in the northwestern states (especially Sonora with a rate of 12.57/100,000 inhabitants compared with the central region (Mexico City with a rate of 0.69/100,000 inhabitants. These data may be related to host genetic factors that are partially responsible for resistance or susceptibility. Therefore, we studied the association of the HLA-DRB1 and HLA-DQB1 alleles with resistance or susceptibility to ALA in two Mexican populations, one each from Mexico City and Sonora. Ninety ALA patients were clinically diagnosed by serology and sonography. Genomic DNA was extracted from peripheral blood mononuclear cells. To establish the genetic identity of both populations, 15 short tandem repeats (STRs were analyzed with multiplexed PCR, and the allelic frequencies of HLA were studied by PCR-SSO using LUMINEX technology. The allele frequencies obtained were compared to an ethnically matched healthy control group (146 individuals. We observed that both affected populations differed genetically from the control group. We also found interesting trends in the population from Mexico City. HLA-DQB1*02 allele frequencies were higher in ALA patients compared to the control group (0.127 vs 0.047; p= 0.01; pc= NS; OR= 2.9, 95% CI= 1.09-8.3. The less frequent alleles in ALA patients were HLA-DRB1*08 (0.118 vs 0.238 in controls; p= 0.01; pc= NS; OR= 0.42, 95% CI= 0.19-0.87 and HLA-DQB1*04 (0.109 vs 0.214; p= 0.02; pc= NS; OR= 0.40, 95% CI= 0.20-0.94. The haplotype HLA-DRB1*08/-DQB1*04 also demonstrated a protective trend against the development of this disease (0.081 vs. 0.178; p=0.02; pc=NS; OR= 0.40, 95% CI= 0.16-0.93. These trends suggest that the prevalent alleles in the population of Mexico City may be associated with protection against the