Publications

role of the entamoeba histolytica cysteine proteinase in amebic liver abscess formation in severe combined immunodeficient mice.	evidence from in vitro studies suggest that the entamoeba histolytica cysteine proteinase plays a role in the tissue lysis and cytopathic effects seen in invasive amebiasis. we used affinity-purified antibodies against a recombinant e. histolytica cysteine proteinase to demonstrate that the proteinase is present extracellularly in amebic liver abscesses in mice with severe combined immunodeficiency (scid mice). treatment of e. histolytica trophozoites with specific cysteine proteinase inhibitor ...	1995	7890426
high affinity binding of the entamoeba histolytica lectin to polyvalent n-acetylgalactosaminides.	entamoeba histolytica trophozoites initiate pathogenic colonization by adherence to host glycoconjugates via an amebic surface lectin which binds to galactose (gal) and n-acetylgalactosamine (galnac) residues. monovalent and multivalent carbohydrate ligands were screened for inhibition of e. histolytica lectin-mediated human red cell hemagglutination, revealing that: (i) the synthetic multivalent neoglycoprotein galnac39bsa (having an average of 39 galnac residues linked to bovine serum albumin) ...	1995	7890626
identification of various circular dna molecules in entamoeba histolytica.		1995	7895848
bile salts help entamoeba histolytica to evade from immune attack.		1994	7896326
host-parasite relationships in amebiasis: conference report.	entamoeba histolytica has been redescribed as the separate species e. histolytica and entamoeba dispar. e. dispar is apparently never invasive in humans, while e. histolytica is the etiologic agent of amebic colitis and liver abscess. virulence factors that may enable e. histolytica to invade include a galactose-specific adhesin, secreted proteases, extracellular matrix receptors, and a cell surface lipophosphoglycan. progress in vaccine development includes the identification of the cysteine-ri ...	1994	7908923
brain abscess due to infection with entamoeba histolytica.	we successfully treated a serious case of entamoeba histolytica infection showing brain abscess, meningitis, and liver abscess by oral administration of metronidazole, intramuscular injection of dehydroemetine, and drainage of the brain abscess. the diagnosis of amebic brain abscess was based on a combination of clinical symptoms and signs, computed tomography and magnetic resonance imaging findings, a positive serologic test result for e. histolytica, a dramatic response to anti-amebic drugs af ...	1994	7915500
the use of an elispot assay to evaluate intestinal and systemic antibody responses to locally administered entamoeba histolytica antigen in mice.	the local induction of humoral immune response to entamoeba histolytica trophozoites in the gut has not been studied. this work reports some of our recent studies aimed to induce optimal immune responses against e. histolytica in mice and to describe a novel approach for monitoring mucosal immune responses induced in the gastrointestinal tract and expressed locally and systemically. we have compared the kinetics of both mucosal and systemic primary antibody responses to e. histolytica in the pey ...	1994	7919810
proteins of entamoeba histolytica trophozoites involved in the adhesion to target cells.	to identify the molecules involved in the adhesion of entamoeba histolytica trophozoites to target cells we used monoclonal antibodies (mabs) and adhesion-deficient mutants. human red blood cells (rbcs) were also used as specific carriers to identify the ameba molecules with affinity to the target cell receptors. mabs adh-1 and adh-2 inhibited adhesion of rbcs to the trophozoites and recognized a 112-kda surface protein that was present in the wild type strain, but was absent or modified in adhe ...	1994	7919814
a monoclonal antibody specific for a 40 kda polypeptide recognizes pathogenic strains of entamoeba histolytica.	in vitro interaction of entamoeba histolytica trophozoites with collagen induces the intracellular formation and release of electron-dense granules (edgs). we determined that four polypeptides in edgs total antigen by sds-page were absent in trophozoite extracts. a monoclonal antibody raised against these edgs recognized a polypeptide of 40 kda specific for the pathogenic strains of e. histolytica. in addition, this mab recognized a 96 kda peptide masked by carbohydrates.	1994	7919818
diagnosis of invasive amoebiasis--time to end the morphology era.		1994	7926897
leucocyte migration inhibition index responses of patients of amoebic liver abscess to various antigens of entamoeba histolytica.	the whole amoebic lysate (wal), sephadex g-200 eluted fraction-i. (f-i), detergent dissected membrane proteins (ddmp), amoebic membrane glycoprotein (amg) and amoebal rna were extracted from e. histolytica. amoebal rna recognized 98.21% where as f-i, amg, ddmp and wal recognised 92.85, 91.07, 89.28 and 75% of total 56 clinically proven and amoebic serology positive amoebic liver abscess cases respectively. intensity of recognition of individual fraction i.e., leucocyte migration inhibition index ...	1994	7927532
entamoeba histolytica interactions with polarized human intestinal caco-2 epithelial cells.	to model the initial pathogenic effects of entamoeba histolytica trophozoites on intestinal epithelial cells, the interactions of e. histolytica hm1-imss trophozoites with polarized human intestinal caco-2 cell monolayers grown on permeabilized filters were examined. trophozoites, when incubated with the apical surface of the monolayers at 37 degrees c, induced a rapid decrease in transepithelial resistance over 15 to 60 min. the transmonolayer resistance response was not associated with changes ...	1994	7927794
heterogeneity of the ribosomal dna episome in strains and species of entamoeba.	ribosomal dna sequences in several species of the genus entamoeba are highly repeated and display restriction fragment-length polymorphism (rflp), which has been used to identify species and differentiate strains. however, the continuous variability of the non-transcribed repeat sequences in the ribosomal episome hinders an accurate typification. looking for more reliable markers, we used dna probes containing conserved sequences in the ribosomal episome--coding regions for the 16s and 5.8s rrna ...	1994	7934884
entamoeba histolytica has an alcohol dehydrogenase homologous to the multifunctional adhe gene product of escherichia coli.	entamoeba histolytica ferments glucose to ethanol under the anaerobic conditions of the human colon. there is special interest in this metabolic pathway because it provides an opportunity for parasite-specific chemotherapy. peptide sequences from a 97-kda e. histolytica protein, which was originally isolated because of extracellular matrix binding properties, were used to clone and sequence a gene that was found to encode an e. histolytica alcohol dehydrogenase and acetaldehyde dehydrogenase (eh ...	1994	7935603
myo-inositol trisphosphate-mediated calcium release from internal stores of entamoeba histolytica.	calcium mobilisation from internal stores of the parasitic protozoan entamoeba histolytica was studied by fluorescence measurements of the calcium indicator quin 2 and 45ca2+ incorporation studies in saponin-permeabilised amoebae. prior energy-dependent calcium sequestration was found to be necessary for subsequent release of calcium by inositol 1,4,5-trisphosphate (ins(1,4,5)p3). both ins(1,4,5)p3 and inositol 2,4,5-trisphosphate (ins(2,4,5)p3) could release calcium equally well from permeabili ...	1994	7935629
diagnostic methods for intestinal parasites in southern iraq with reference to strongyloides stercoralis.	three hundred and thirty-two stool samples were examined for the presence of intestinal parasites including strongyloides stercoralis. each sample was processed and examined by direct smear, formalin-ether and harada and mori culture methods. nine parasites were recovered from patients attending basrah teaching hospital, southern iraq during 1989. the prevalence rate of infection was 64.2%. it was higher in rural (74.2%) than in urban (57.5%) region (p < 0.01). sex distribution was 120 (36.1%) m ...	1993	7939941
[amoebiasis--a problem in patients with ulcerative colitis].	the increasing problem is presented of entamoeba histolytica invasion in patients with ulcerative colitis. the diagnostic-therapeutic management in five patients with amoebiasis is discussed in detail. this parasitic invasion occurred in five out of 103 patients with ulcerative colitis which accounts for 4.85%. this data is important for the treatment of chronically ill patients with ulcerative colitis.	1994	7941573
the sensitivity of axenic 200:nih entamoeba histolytica to bacitracin and its zinc salt.	this study extends the previous knowledge of the action of bacitracin zinc against xenic cultures of entamoeba histolytica. results presented here, using axenic e. histolytica, confirm the enhanced activity of bacitracin zinc as compared to native bacitracin and demonstrate that this enhancement is due to a direct effect upon the trophozoite. in the presence of zinc, amoebastatic concentrations of bacitracin became amoebacidal. the expression of the amoebacidal characteristics of 5 g/l bacitraci ...	1994	7942350
secretory immunoglobulin a antibodies to the galactose-inhibitable adherence protein in the saliva of patients with amebic liver disease.	monoclonal antibodies directed against the 260-kd galactose-inhibitable adherence protein (giap) of entamoeba histolytica inhibit binding of amebic trophozoites to purified colonic mucins, suggesting that anti-giap secretory immunoglobulin a (siga) may have a role in host defense in invasive amebiasis. we determined by enzyme-linked immunosorbent assay (elisa) whether a salivary anti-giap siga response was present in patients from the republic of south africa with invasive e. histolytica infecti ...	1994	7943572
cyclospora infection in adults infected with hiv. clinical manifestations, treatment, and prophylaxis.	to determine the prevalence and clinical manifestations of cyclospora in haitians infected with human immunodeficiency virus (hiv) who have diarrhea and to evaluate therapy and prophylaxis.	1994	7944073
antibacterial activity of metal complexes of benzil and benzoin thiosemicarbazones.	the metal (ii) complexes of benzyl and benzoin thiosemicarbazones have been synthesized and characterized. they were studied for their antibacterial, antifungal and amoebicidal activity in vitro and for their toxicity in vivo. the ligands and their metal complexes exhibited low antibacterial and amoebicidal activity. the metal chelates of benzoin thiosemicarbazone seem to be the most active compounds.	1994	7945719
amebiasis: human infection with entamoeba histolytica.		1994	7948936
[effects of monoclonal antibodies on phagocytosis of entamoeba histolytica to human erythrocytes].	two monoclonal antibodies 3f7 and 4g6 were produced respectively against plasma membrane and nucleus-cytoplasm of entamoeba histolytica. the erythrocytophagous quantification and ability of pathogenic strain hm-1:imss were evaluated by microscopy immediately at 5 min and 10 min after incubation with mcab 3f7 and mcab 4g6. sera from normal mice and monoclonal antibody tce 04 against trypanosoma cruzi were prepared as negative controls. the mcab 3f7 showed stronger inhibitory action on the erythro ...	1994	7955164
entamoeba histolytica: mechanism of surface receptor capping.	binding of antibodies to the surface of the parasitic protozoan entamoeba histolytica induces capping and release of antigen-antibody complexes, in a process that may be an effective means of evading the host immune response. to analyze the mechanism of capping in e. histolytica trophozoites, optimal conditions were determined for cap induction by sera from patients with amebic liver abscess, by polyclonal anti-amebic antibodies, and by concanavalin a. cocapping of actin and myosin was documente ...	1994	7957761
entamoeba histolytica: pkc transduction pathway activation in the trophozoite-fibronectin interaction.	interaction of entamoeba histolytica trophozoites with fibronectin (fn) induces reorganization of the actin cytoskeleton and an increase in proteolytic activities that results in the degradation of the bound protein. the binding is mediated by a 37-kda fn "receptor" localized in the trophozoite surface and associated to the cytoskeleton. the intracellular signals triggered by the ligand-receptor interaction are not well understood but it is plausible that they drive the observed responses. to ad ...	1994	7957762
entamoeba histolytica: target cells killed by trophozoites undergo dna fragmentation which is not blocked by bcl-2.	amebic destruction of neutrophils and macrophages is contact-dependent. adherence is mediated by a galactose-specific surface lectin on the amebic membrane. the pathway by which contact-dependent cytolysis of the target cell occurs is unknown. we hypothesized that target cell death is due to the triggering of apoptosis (programmed cell death) by the amebae. the purpose of this study was to determine whether target cell dna is fragmented into a ladder pattern characteristic of apoptosis and to te ...	1994	7957763
characterization of two distinct gene transcripts for ribosomal protein l21 from pathogenic and nonpathogenic strains of entamoeba histolytica.	a second gene (rp-l21) copy, clone g34, coding for ribosomal (r-) protein l21, was isolated from the pathogenic (p) strain hm-1:imss cl6 of the intestinal parasite entamoeba histolytica (eh). the gene was compared to the previously isolated copy, gle3 [petter et al., mol. biochem. parasitol. 56 (1992) 329-334], with respect to its primary structure, mrna levels and binding to the r-complex during translation. unlike the gle3 gene copy [petter et al., mol. biochem. parasitol. 56 (1992) 329-334], ...	1994	7959049
[microbiological diagnosis of malaria and amoebiasis].	all stages of malaria and amebiasis may be sensitively and specifically diagnosed by means of microbiological methods. microscopical parasitology holds a key position when supplemented by immunodiagnostic assays. molecular biology techniques are currently still inferior to the above procedure. tests for the differentiation between pathogenic and nonpathogenic entamoeba histolytica (entamoeba dispar) require further simplification before generally applicable.	1994	7959857
[therapy for malaria and amoebiasis].	treatment of malaria depends on the infecting plasmodium species. in plasmodium falciparum malaria the treatment also depends on whether chloroquine resistances occur and whether the course is uncomplicated or complicated. uncomplicated cases are cared for with chloroquine and with mefloquine or halofantrine when the patient comes from areas with chloroquine resistances. patients with complicated plasmodium falciparum malaria must get chinine and doxycycline. a careful fluid balance is extremely ...	1994	7959858
detection of ubiquinone in parasitic and free-living protozoa, including species devoid of mitochondria.	ubiquinone (coenzyme q, coq) was analyzed and individual homologues quantified in 11 species of parasitic and free-living protozoa by a combination of thin-layer chromatography and high performance liquid chromatography. fast atom bombardment ionization-mass spectrometry was used for the first time to confirm the identity of the fractionated coq homologues and proved to be a fast, gentle and convenient method for ubiquinone identification. ubiquinone was detected in all organisms including those ...	1994	7969263
purification and molecular characterization of the nad(+)-dependent acetaldehyde/alcohol dehydrogenase from entamoeba histolytica.	a bifunctional 95 kda polypeptide (ehadh2) harbouring acetaldehyde dehydrogenase and alcohol dehydrogenase activities was purified to homogeneity from trophozoite extracts of the protozoan parasite entamoeba histolytica. kinetic studies revealed that the enzyme utilizes nad+ rather than nadp+ as cofactor. km values for acetyl-coa, acetaldehyde and ethanol were found to be 0.015, 0.15 and 80 mm respectively in the presence of 0.2 mm nad+. the primary structure of ehadh2 as deduced from respective ...	1994	7980441
[gnathostomiasis after a stay in thailand].	during a 4-week holiday in thailand a 13-year-old boy from germany briefly fell ill with diarrhoea without blood-tinged stools and fever. 5 months later oedematous, reddish swellings occurred, at first on the right upper arm, later over the right side of the chest. especially at night these swellings were associated with severe local and generalized itching. bilaterally the axillary lymph-nodes were hard and slightly enlarged. there was a marked eosinophilia of 56%, the white count was 22,700/mi ...	1994	7982372
monoclonal antibody-based immunohistochemical demonstration of entamoeba histolytica in liver tissues of experimentally infected hamster (mesocricetus auratus).	histopathological changes and the presence of entamoeba histolytica trophozoites was sequentially followed after intrahepatic inoculation of the parasites in 42 hamsters, 35 of which received no treatment whereas the remaining seven were treated with metronidazole. the liver tissues were examined for amoebic trophozoites by a monoclonal antibody (mab)-based immunofluorescence assay (ifa), a mab-based immunoperoxidase (ipx) and h & e staining. the number of hamsters developing abscesses was incre ...	1994	7982753
expression and characterization of a rac family protein kinase of entamoeba histolytica.	we previously reported the isolation from entamoeba histolytica of a novel rac family protein kinase gene, termed ehrac1, for "related to camp-dependent protein kinases and protein kinase cs". to study the function and properties of this kinase gene further, we fused the full-length coding region and the truncated catalytic domain of the ehrac1 gene in frame with the gene encoding glutathione s-transferase in the pgex-kg vector and expressed the fusion in escherichia coli. the thrombin-cleaved a ...	1994	7984173
primary structure of the entamoeba histolytica gene (ehvma1) encoding the catalytic peptide of a putative vacuolar membrane proton-transporting atpase (v-atpase).		1994	7984182
an intron-containing gene coding for a novel 39-kilodalton antigen of entamoeba histolytica.		1994	7984185
[the infectious etiology of acute diarrheal diseases in the republic of cuba, 1991].	this study was carried out in 1991 to learn the behavior of enteropathogenic agents causing acute diarrheal diseases in cuba. 30 children, admitted in hospitals or seen in outpatient services for acute diarrheal diseases, were selected in each province taking into account that they had not received antibiotic or chemotherapy treatments in the previous 72 hours. feces samples were taken from all patients for virological, bacteriological, and parasitological studies, and results were sent to the p ...	1993	7984819
amebic abscess of the spleen complicated by metronidazole-induced neurotoxicity: case report.	we describe a patient with a liver abscess due to entamoeba histolytica, in whom metronidazole therapy (total dose, 21 g over 14 days) was complicated by reversible deafness, tinnitus, and ataxia and who relapsed 5 months later with a splenic abscess. two courses of tinidazole (the second in combination with percutaneous aspiration of the abscess) were required to achieve cure.	1994	7986915
prevalence of intestinal parasites in rural areas of district shahjahanpur, uttar pradesh.	a stool survey was carried out in some of the villages of dadraul and bhawal khera phc's of district shahjahanpur (uttar pradesh). out of 381 individuals examined 111 (29.2 per cent) were found positive for one or the other intestinal parasite. ascaris lumbricoides superseded all the parasites by showing a positivity of 17.85 percent. other parasites found were hookworm, hymenolepis nana, tapeworm, trichuris trichiura, enterobius vermicularis, entamoeba histolytica, e. coli and giardia lamblia. ...	1994	7989672
detection of immune complexes in tissues of persons infected with entamoeba histolytica.	immune complexes were detected by radioimmunoassay in colonic tissue from 71 to 122 patients (58%) excreting entamoeba histolytica cysts and in liver tissue from 5 of 16 of these patients. complexes were also found in colonic tissue from 9 of 56 other patients (16%) who were not excreting cysts.	1994	7992334
a beta 1 integrin-like molecule in entamoeba histolytica.	human invasive amoebiasis is highly destructive, causing rapid necrosis and liquefaction of all tissues reached by the trophozoites. degradation of extracellular matrix components (emc) has been demonstrated during invasion of the basal lamina. pursuing the idea that trophozoites might behave similarly to other invasive cells with respect to their interaction with emc, plasma membrane proteins biochemically or functionally related to integrins were looked for. a 140 kda molecular mass membrane p ...	1994	7992351
an attempt at reversibility and increase of the virulence of axenic strains of entamoeba histolytica.	in this study we have tried to verify whether the interaction "in vitro" with bacteria or small pieces of normal hamster liver would modify the pathogenic behavior of axenic strains of e. histolytica: avirulent ones (icb-32 and icb-rps), of attenuated virulence (icb-csp and hm1) and of mean virulence (icb-462). every attempt to render virulent, recover or increase the virulence of axenic strains of e. histolytica has failed.	1993	7997753
entamoeba histolytica zymodemes in children of osasco, são paulo.		1993	7997764
acid sphingomyelinase possesses a domain homologous to its activator proteins: saposins b and d.	an n-terminal region of the acid sphingomyelinase sequence (residues 89-165) is shown to be homologous to saposin-type sequences. by analogy with the known functions of saposins, this sphingomyelinase saposin-type domain may possess lipid-binding and/or sphingomyelinase-activator properties. this finding may prove to be important in the understanding of niemann-pick disease, which results from sphingomyelinase deficiency.	1994	8003971
recent trends in the diagnosis of amoebiasis.		1993	8005981
exercise-induced diarrhea: when to wonder.	exercise-associated lower gastrointestinal symptoms seem to be a fairly common clinical finding occurring in anywhere from 10-50% of runners. however, it is unclear what percentage of those affected may have discrete medical conditions that are exacerbated by strenuous physical exertion. perhaps, difficult physical training sessions function as a "stress test" for the colon. a case report of exercise induced diarrhea is presented with a discussion of the current medical literature and proposed m ...	1994	8007797
[an analysis of the antigenic structure of the membrane complex in leishmania].		1994	8015520
symptomatic amebic colitis in a japanese homosexual aids patient.	a 30-year-old japanese homosexual aids patient was admitted to hospital because of kaposi's sarcoma and mild diarrhea on february 4, 1993. mud-like stool with blood and mucous was recognized after admission. although serologic tests for entamoeba histolytica were negative, trophozoites of e. histolytica were identified in his bloody stool. daily doses of 1,000 mg of metronidazole were given orally for 6 days and then 750 mg for 4 days, and good results were observed. his cd4 count was 19.5/mm3. ...	1994	8019042
isolation and characterization of a species-specific multicopy dna sequence from entamoeba histolytica.	a genomic library of entamoeba histolytica (pathogenic strain hm-1:imss) was screened to detect repetitive dna clones other than those from the highly abundant ribosomal dna (rdna). one such clone (hmc) had a 2.3 kb insert which hybridized with the main genome and not the rdna circle. southern hybridization of e. histolytica genomic dna, digested with ecor i and probed with hmc, showed multiple bands. the banding pattern was identical in all axenic pathogenic strains tested. differences, however ...	1994	8022651
intestinal parasitism in the united states: update on a continuing problem.	to document patterns of intestinal parasitism in the united states, we analyzed results of 216,275 stool specimens examined by the state diagnostic laboratories in 1987; parasites were found in 20.0%. percentages were highest for protozoans: giardia lamblia (7.2%), entamoeba coli and endolimax nana (4.2% each), blastocystis hominis (2.6%), and entamoeba histolytica (0.9%). the most commonly identified helminths were nematodes: hookworm (1.5%), trichuris trichiura (1.2%), and ascaris lumbricoides ...	1994	8024063
antiparasitic activity of diallyl trisulfide (dasuansu) on human and animal pathogenic protozoa (trypanosoma sp., entamoeba histolytica and giardia lamblia) in vitro.	garlic (allium sativum l.) and one of its major components, allicin, have been known to have antibacterial and antifungal activity for a long time. diallyl trisulfide is a chemically stable final transformation product of allicin which was synthesized in 1981 in china and used for treatment of bacterial, fungal and parasitic infections in man. the activity of diallyl trisulfide was investigated in several important protozoan parasites in vitro. the ic50 (concentration which inhibits metabolism o ...	1994	8024350
diagnosis of amebic dysentery by detection of entamoeba histolytica fecal antigen by an invasive strain-specific, monoclonal antibody-based enzyme-linked immunosorbent assay.	an invasive strain-specific monoclonal antibody against entamoeba histolytica has been used in a capture enzyme-linked immunosorbent assay (elisa) for the detection of invasive e. histolytica fecal antigen in clinical specimens and for the diagnosis of amebic dysentery in patients from bangladesh. the fecal antigen capture elisa (fac-elisa) did not cross-react with other parasite species in the clinical specimens or with noninvasive e. histolytica present in those specimens and in experimentally ...	1994	8027351
enzyme location and metabolism in entamoeba histolytica.		1993	8032076
invasive amoebiasis is associated with the development of anti-neutrophil cytoplasmic antibody.	features of tissue damage in invasive amoebiasis, in particular polymorphonuclear neutrophil (pmn) degranulation and vasculitis, bear resemblance to that seen in wegener's granulomatosis, the latter being associated with the presence of anti-neutrophil cytoplasmic antibodies (anca). we therefore tested sera from patients with confirmed amoebic liver abscess (ala) for the presence of anca by means of an indirect fluorescent antibody test using pure neutrophils as substrate. anca was detected in 9 ...	1994	8033420
entamoeba histolytica and e. dispar.		1994	8036693
adherence and cytotoxicity of entamoeba histolytica or how lectins let parasites stick around.		1994	8039871
cloning of entamoeba genes encoding proteolipids of putative vacuolar proton-translocating atpases.	molecular cloning techniques were used to identify genes encoding the proteolipids of putative vacuolar proton-transporting atpases (v-atpases; ec 3.6.1.35) of entamoeba histolytica (ehvma3) and entamoeba dispar. the ehvma3 gene encoded a 177-amino-acid peptide, with an m(r) of 18,110, which showed extensive positional identities with peptides of e. dispar (92%), schizosaccharomyces pombe (58%), and humans (56%).	1994	8039932
transfection and transient expression of chloramphenicol acetyltransferase gene in the protozoan parasite entamoeba histolytica.	hybrid plasmids were constructed and used for successful transfection and transient expression of the chloramphenicol acetyltransferase (cat) gene in the protozoan parasite entamoeba histolytica. transfection was performed by electroporation of the amebae in a potassium phosphate-based buffer under conditions of 3000 v/cm and 25 microf, resulting in a time constant of 0.4 ms. expression of cat activity was achieved with constructs in which the cat coding region was flanked by untranslated upstre ...	1994	8041751
transient transfection of the enteric parasite entamoeba histolytica and expression of firefly luciferase.	development of dna-mediated transfection in entamoeba histolytica will facilitate basic research toward the control of this protozoan parasite. a transient transfection system was established by using the firefly luciferase gene ligated to the 5' and 3' flanking regions of the amebic hgl1 gene. the optimal construct tested encoded an hgl1-luciferase fusion protein and contained 1 kb of 5' flanking sequence with 16 bases of coding sequence from the hgl1 gene ligated in-frame to the luciferase sta ...	1994	8041752
[epidemiologic setting of the agricultural use of sewage: valle del mezquital, mexico].	wastewater from mexico city is used to irrigate over 85,000 hectares mainly of fodder and cereal crops in the mezquital valley. a cross-sectional study method is being used to test the impact of exposure to raw wastewater and wastewater from storage reservoirs on diarrheal disease and parasitic infections in farmworkers and their families. the study population in the rainy season survey included 1,900 households: 680 households where the farmworker is exposed to untreated wastewater (exposed gro ...	1994	8042068
characterization of monoclonal antibodies to conserved antigens of entamoeba histolytica and e. dispar and development of a stool elisa.	eight murine monoclonal antibodies (mabs) were generated against entamoeba histolytica nih:200. all mabs reacted with three axenic strains of e. histolytica, nih:200, hm-1: imms, and saw 1734r clar, but not with enteric bacteria or giardia lamblia. five of the mabs reacted with low-molecular-weight, periodate-sensitive antigens of 14-21 kd, while one (ab31) reacted with high-molecular-weight, 90 to 200-kd protein determinants. mab pc14 appeared to be specific for antigen in its native state. ano ...	1994	8050777
extra-intestinal amebiasis: clinical presentation in a non-endemic setting.	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 or more amebic liver abscesses on ultrasonography. fever was the most common finding, present in 91% of the cases. the most striking observation was the lack of both abdominal pain and tenderness in 22 ...	1993	8052815
aids and the gut.	there are increasing challenges for the practising gastroenterologist in treating aids-related gastrointestinal diseases. the differential diagnoses of dysphagia and odynophagia include cytomegalovirus (cmv) and herpes simplex virus (hsv) infection, non-specific aphthous ulceration and non-aids oesophageal diseases, especially reflux oesophagitis. chronic subacute abdominal pain with nausea, vomiting, early satiety and weight loss is suggestive of an obstructive lesion caused by lymphoma or kapo ...	1994	8054532
direct amplification and differentiation of pathogenic and nonpathogenic entamoeba histolytica dna from stool specimens.	discrimination of pathogenic and nonpathogenic entamoeba histolytica is of great clinical importance. a simple and rapid dna extraction method that can be used directly with stool specimens was developed without the need for prior cultivation of the parasites. the entire protocol can be performed at room temperature in a 1.5-ml microcentrifuge tube format. there is no dna precipitation step. the subsequent nested polymerase chain reaction consists of an initial e. histolytica-specific amplificat ...	1994	8059910
[prevalence of enteropathogens in children with liquid diarrhea].	between january 1 and october 31, 1991 148 samples of feces corresponding to the same number of children with acute diarrhea, aged 0-2 years, admitted to hospital o'horan of the secretariat of health in the city of merida, yucatan, mexico, were studied. stools from 105 (70.9%) patients were described as watery diarrhea; from these samples at least one enteric pathogen was detected in 49 (46.6%): a single pathogen was isolated in 37 (35.2%), and mixed infections were observed in 12 (11.4%). we is ...	1993	8066329
detection of cryptosporidium and giardia intestinalis in bedouin children from southern israel.	during an 18 month period, a total of 4796 stool specimens collected from 151 bedouin children enrolled in a cohort study and followed from birth, were screened for giardia intestinalis, cryptosporidium spp. and other intestinal parasites. specimens were collected in phenol-alcohol-formalin (paf) preservative and examined prior to, and after, formalin-ether concentration (fec). during 6 months of the second year giardia intestinalis was observed in 17.6% of the specimens and cryptosporidium in 0 ...	1994	8070959
antibodies to the serine rich entamoeba histolytica protein (srehp) prevent amoebic liver abscess in severe combined immunodeficient (scid) mice.	amoebic liver abscess caused by entamoeba histolytica is a major cause of morbidity and mortality worldwide. we used mice with severe combined immunodeficiency (scid mice) to study the role of antibody in protection from amoebic liver abscess, and to identify protective antigens of e. histolytica. antisera to recombinant versions of two major surface antigens of e. histolytica, the serine rich e. histolytica protein (srehp) and the 170 kda adhesin were used in this study. we found that 100% of s ...	1994	8072766
[bacterial dysentery in 1992].		1994	8073150
phylogenetic place of a mitochondria-lacking protozoan, entamoeba histolytica, inferred from amino acid sequences of elongation factor 2'.	partial dna regions encoding a major part of translation elongation factor 2 (ef-2) from a mitochondria-lacking protozoan, entamoeba histolytica, were amplified by polymerase chain reaction and their primary structures were analyzed. the deduced amino acid sequence was aligned with other eukaryotic and archaebacterial ef-2's, and the phylogenetic relationships among eukaryotes were inferred by the maximum likelihood (ml) method. the ml analyses using four different stochastic models of amino aci ...	1994	8074887
socio-economic factors associated with intestinal parasites among children living in gombak, malaysia.	fecal specimens collected from 456 school children in gombak, malaysia, revealed an overall prevalence rate of 62.9%. the most common parasite found was trichuris trichiura (47.1%) followed by giardia intestinalis (14.7%), entamoeba coli (11.4%), entamoeba histolytica (9.9%) and ascaris lumbricoides (7.9%). infection rates were high among the indonesian immigrant workers' children (90%) followed by the orang asli (79.5%), malay (59.4%) and indians (36.4%). females (66.3%) had a higher prevalence ...	1994	8074940
cloning, genomic organization and transcription of the entamoeba histolytica alpha-tubulin-encoding gene.	we have isolated and characterized an entamoeba histolytica alpha-tubulin (alpha tub)-encoding gene (eh alpha tub). a 700-bp dna fragment was amplified by pcr using primers derived from consensus alpha- and beta-tub amino acid (aa) sequences from different organisms and e. histolytica dna as the template. these pcr fragments were used to screen both genomic dna and cdna libraries in order to isolate an eh alpha tub structural gene. two overlapping clones containing the complete alpha tub orf (13 ...	1994	8076825
two-year study of endemic enteric pathogens associated with acute diarrhea in new caledonia.	a longitudinal study of diarrheal disease among patients of all ages with acute diarrhea was carried out in new caledonia from january 1990 to december 1991. stool samples from 2,088 diarrheal patients were examined for parasites, rotavirus, and bacterial pathogens. potential sources of contamination (drinking water, seawater and bovine and porcine feces) were investigated. one or more enteric pathogens were identified in 41.8 and 40.6% of the persons with diarrhea, in 1990 and 1991, respectivel ...	1994	8077399
molecular cloning of ras and rap genes from entamoeba histolytica.	to better understand growth regulation in the protozoan parasite entamoeba histolytica, ameba genes homologous to the ras oncogene and rap (krev-1) anti-oncogene were cloned. two putative ameba ras genes (ehras1 and ehras2) were identified, which contain 205 and 203 amino acid (aa) open reading frames (orfs), respectively. the ehras1 orf shows an 91% positional identity with that of ehras2, a 55% identity with dictyostelium discoideum (dd) ras, and a 47% identity with human (hs) ras. two ameba r ...	1994	8078515
zymodeme alteration of entamoeba histolytica isolates under varying conditions.	cysts of entamoeba histolytica obtained from 2 asymptomatic subjects were cloned in vitro and the isoenzyme patterns and virulence of the cultures derived from them were determined. incubation in diamond's tyi-s-33 medium with crithidia sp. for 80 d resulted in a change from zymodeme iii to zymodeme ii, with consistent virulence. axenization by replacing crithidia sp. with crithidial lysate had no further effect on the zymodeme but the virulence of the amoebae was attenuated. a reversal to zymod ...	1993	8080488
identification of a putative pore-forming hemolysin active at acid ph in leishmania amazonensis.	several organisms, including the protozoa entamoeba histolytica and trypanosoma cruzi, have been shown to contain pore-forming proteins (pfp) thought to play a role in the pathogenesis of the diseases they generate. in the present report, we show that promastigotes of leishmania amazonensis express a hemolysin that appears to cause colloid-osmotic lysis, typical of pore formation. this hemolysin affects red blood cells of different species at 37 degrees c, but not at 0 degrees c, with maximum ac ...	1994	8081268
rapid latex agglutination test for extraluminal amoebiasis.	to develop a rapid latex agglutination screening test for invasive amoebiasis.	1994	8089223
differential effects of the (+)- and (-)-gossypol enantiomers upon entamoeba histolytica axenic cultures.	the in-vitro anti-amoebic effects of (+/-)-, (+)-, (-)-gossypol and emetine were tested against axenic trophozoites from five entamoeba histolytica strains. the (-)-isomer was more active than the racemate and the (+)-isomer. these results indicate that the gossypol anti-amoebic activity is mainly due to its content of (-)-gossypol in all strains tested.	1993	8095532
[intestinal parasite infections in rural students of chiloé archipelago, x region, chile].	in order to contribute to the knowledge of intestinal parasite infection a survey was performed in 462 primary school children from eight rural localities sited in two islands of the chiloe archipelago. stool samples and perianal scotch tape scrapings for intestinal protozoa and helminths were microscopically examined. the prevalence rates of the main species found were: ascaris lumbricoides 43.3%, trichuris trichiura 26.8%, enterobius vernicularis 20.1%, entamoeba histolytica 5.6%, giardia inte ...	1993	8110371
a glyceraldehyde-3-phosphate dehydrogenase with eubacterial features in the amitochondriate eukaryote, trichomonas vaginalis.	glyceraldehyde-3-phosphate dehydrogenase (gapdh), localized in the cytosol of trichomonas vaginalis, was partially purified. the enzyme is specific for nad+ and is similar in most of its catalytic properties to glycolytic gapdhs from other organisms. its sensitivity to koningic acid is similar to levels observed in gapdhs from eubacteria and two orders of magnitude lower than those observed for eukaryotic gapdhs. the complete amino acid sequence of t. vaginalis gapdh was derived from the n-termi ...	1993	8114116
analysis of a polymorphic locus present upstream of rdna transcription units in the extrachromosomal circle of entamoeba histolytica.		1993	8114815
molecular cloning of the gene for a novel abc superfamily transporter of entamoeba histolytica.		1993	8114816
primary structure of the pyruvate phosphate dikinase in entamoeba histolytica.		1993	8114821
analysis of the gene family encoding the entamoeba histolytica galactose-specific adhesin 170-kda subunit.	the 170-kda or heavy subunit of the galactose binding adhesin of entamoeba histolytica is seminal in target cell binding and lysis. to determine the existence and complexity of the 170-kda subunit gene family, hgl, an amebic genomic library in lambda phage was hybridized with dna fragments from the 5' or 3' ends of hgl1. termini from three distinct heavy subunit genes were identified including hgl1, hgl2, and a third, unreported gene designated hgl3. the open reading frame of hgl3 was sequenced ...	1993	8114826
intracellular digestion of human erythrocytes by entamoeba histolytica: a kinetic study in vitro.	the objective of this investigation was to quantitatively evaluate, by using light and transmission electron microscopy, the intracellular digestion of human erythrocytes (he), ingested by entamoeba histolytica trophozoites in vitro. amebas fed 10 min with he were postincubated 3-12 h at 36.5 degrees c without he, and fixed with glutaraldehyde. after staining by the benzidine reaction, he per ameba, and percent of amebas containing at least one he were determined by light microscopy. trophozoite ...	1993	8118158
protein phylogeny gives a robust estimation for early divergences of eukaryotes: phylogenetic place of a mitochondria-lacking protozoan, giardia lamblia.	a partial nucleotide sequence of the mrna encoding a major part of elongation factor 1 alpha (ef1 alpha) from a mitochondria-lacking protozoan, giardia lamblia, was reported, and the phylogenetic relationship among lower eukaryotes was inferred by the maximum-likelihood and maximum-parsimony methods of protein phylogeny. both the methods consistently demonstrated that, g. lamblia among the four protozoan species being analyzed, is the earliest offshoot of the eukaryotic tree. although the giardi ...	1994	8121287
amoebic brain abscess: a rare but serious complication of entamoeba histolytica infection.		1994	8126521
coding of hemolysins within the ribosomal rna repeat on a plasmid in entamoeba histolytica.	the pathogenesis of amoebic dysentery is a result of cytolysis of the colonic mucosa by the parasitic protozoan entamoeba histolytica. the cytolysis results in extensive local ulceration and allows the amoeba to penetrate and metastasize to distant sites. factors involved in this process were defined with three clones that express hemolytic activities in escherichia coli. these potential amoebic virulence determinants were also toxic to human colonic epithelial cells, the primary cellular target ...	1994	8128227
[evaluation of 3 tests applied in the immunological diagnosis of hepatic amebiasis in gabon].	the diagnosis of hepatic amoebiasis is not always easy. in case of suspicion of hepatic amoebiasis in an endemic area, the patient is immediately treated with a 5-nitroimidazole. immunological diagnosis is indispensable. after a comparative study of bla, iha and ifa reactions, the bla test has shown to be well adapted to the context of a country with insufficient sanitary infrastructure. the bla test is easily performed and enables rapid detection of antibodies. the result obtained in about 5 mi ...	1993	8129470
protection of gerbils from amebic liver abscess by immunization with a recombinant entamoeba histolytica antigen.	amebiasis, infection by the intestinal protozoan parasite entamoeba histolytica, is a leading parasitic cause of death. as a step in the development of a recombinant antigen vaccine to prevent e. histolytica infection, we looked at the ability of a recombinant version of the serine-rich e. histolytica protein (srehp) to elicit a protective immune response against invasive amebic disease. gerbils, a standard model for amebic liver abscess, were immunized with either a recombinant srehp/maltose-bi ...	1994	8132322
crude or recombinant proteins applied to latex agglutination, complement fixation and enzyme-linked immunosorbent assays for the serodiagnosis of invasive amebiasis.	three different agglutination tests were developed for the detection of serum antibodies against entamoeba histolytica. these tests are based on carboxylated polystyrene beads loaded either with a purified recombinant e. histolytica protein, designated receh-p1, or a soluble fraction, or a membrane fraction (m-la) both prepared from e. histolytica trophozoites. the three agglutination tests were compared with an enzyme-linked immunosorbent assay and a complement fixation test based on crude solu ...	1993	8134767
in vitro antiplasmodial, antiamoebic, and cytotoxic activities of a series of bisbenzylisoquinoline alkaloids.	twenty-four bisbenzylisoquinoline alkaloids were screened for antiplasmoidal, antiamoebic, and cytotoxic activities by use of in vitro microtests. eight of the alkaloids had antiplasmodial activity, with a 50% inhibitory concentration (ic50) of less than 1 microm against a multidrug-resistant strain of plasmodium falciparum (chloroquine had an ic50 of 0.2 microm). the three alkaloids most active against entamoeba histolytica, aromoline, isotrilobine, and insularine, had ic50s of 5 to 11.1 microm ...	1994	8141587
cytolytic and antibacterial activity of synthetic peptides derived from amoebapore, the pore-forming peptide of entamoeba histolytica.	the pore-forming peptide amoebapore is considered part of the cytolytic armament of pathogenic entamoeba histolytica. amoebapore is composed of 77 amino acid residues arranged in four alpha-helical domains. for structure-function analysis, synthetic peptides were constructed corresponding to these four domains: h1 (residues 1-22), h2 (25-39), h3 (40-64), and h4 (67-77). the peptides h1 and h3, representing two highly amphipathic alpha-helical regions of amoebapore, possessed pore-forming activit ...	1994	8146160
inhibitory activity of saccharomyces yeasts on the adhesion of entamoeba histolytica trophozoites to human erythrocytes in vitro.	adhesion to target cells represents the first step in infection by entamoeba histolytica. binding of axenic amoeba (hmi strain) to human red cells in vitro was employed as a model of the adhesion process. the influence of precontact of trophozoites with suspensions of live saccharomyces boulardii yeasts, their fractions (membranes and yeast-content supernatant before and after filtration to eliminate the membrane) or yeast culture medium before and after fermentation was investigated. n-acetylga ...	1994	8153119
chemotherapy of entamoeba histolytica: studies in vitro with bacitracin and its zinc salt.	twenty-one entamoeba histolytica isolates from a range of geographical locations and representing 3 different zymodemes were tested under xenic anaerobic conditions for their sensitivities to bacitracin and bactracin zinc. isolates were over 13 times more sensitive to bacitracin zinc than to bacitracin. our results indicate that bacitracin zinc may form the basis of an alternative non-toxic treatment of luminal amoebiasis.	1994	8154020
[research of antiparasitic agents: 1(nitrophenyl)-3-(methyl-3-indolyl)-prop-2-ene-1-ones (nitroindolylchalcones)].	the synthesis and the study of the antiparasitic properties of various 1-(nitro-phényl)-3-(méthyl-3-indolyl)-prop-2-ene-1-ones (nitroindolylchalcones) show interesting antiprotozoal activities on e. histolytica and t. vaginalis. no significative activity appears in vivo with animals on helminthes.	1993	8154794
endometrial amoebiasis.	a case of endometrial infection by entamoeba histolytica is described in an elderly lady who presented with profuse vaginal discharge and was clinically misdiagnosed as endometrial carcinoma.	1993	8157142
the etiology of early childhood diarrhea: a community study from guinea-bissau.	a potential enteropathogen was found in 50% of 1219 diarrheal episodes and 48% of 511 asymptomatic controls in a 1-year community study of childhood diarrhea. rotavirus (3% of episodes), cryptosporidium species (6%), and enteropathogenic escherichia coli (epec) with epec adherence factor (4%) were more prevalent in cases than controls. giardia lamblia (19%) was the most prevalent organism but was not associated with diarrhea. enterotoxigenic e. coli (12%), strongyloides stercoralis (5%), shigell ...	1994	8158030
axenic cultivation of entamoeba histolytica from liver abscess and its zymodeme.	a local strain of entamoeba histolytica, the hth-56: mutm from a human liver abscess was successfully axenized. the culture was initially established monoxenically in diamond's tyi-s-33 medium in the presence of crithidia luciliae and maintained at 34 +/- 0.5 degrees c. after 5 passages it was adapted to axenic cultivation by addition of 0.02% bacto agar in diamond's tyi-s-33 medium in place of crithidia. subcultures or replacement with fresh complete media were done twice or thrice for 7 days, ...	1993	8160057
value of microscopy in the diagnosis of dysentery associated with invasive entamoeba histolytica.	to assess the reliability of the detection of erythrophagocytic amoebic trophozoites in stool samples in the diagnosis of dysentery associated with invasive entamoeba histolytica.	1994	8163695
seroepidemiology of amebiasis in mexico.	the presence of serum antibodies to entamoeba histolytica was detected by indirect hemagglutination in a representative sample of the 32 federal entities of the mexican republic. this study was designed to include biologic, geographic, social, economic, and educational variables. the total percentage of positive sera was 8.41%. seroprevalence varied with geographic zones, with the south central, south pacific, and yucatan peninsula areas showing the highest values (> or = 9%), and the north, nor ...	1994	8166347