| [isolation, characterization and in vitro translation of rna from clones of entamoeba histolytica deficient in adhesion]. | | 1986 | 2439050 |
| [axenic encystment of e. histolytica]. | | 1986 | 2439051 |
| wall synthesis in axenic cultures of entamoeba histolytica grown in pehps medium. | | 1986 | 2439052 |
| [role of histamine in the local anti-amebic immune response]. | | 1986 | 2439053 |
| sensitivity of protein and rna synthesis to emetine in axenic entamoeba histolytica. | the action of emetine on the incorporation of (14c)1-dl-valine and (14c)-8-adenine in tca insoluble fraction of axenic entamoeba histolytica was investigated. these compounds were almost exclusively incorporated in the 'protein' and 'rna' fractions, respectively. incorporation of the purine showed a significantly higher sensitivity to emetine. while the percentage inhibition of valine incorporation by emetine decreased with increasing ph, the susceptibility of adenine incorporation was greater i ... | 1987 | 2449783 |
| the cellular regulation of vesicle exocytosis by entamoeba histolytica. | we studied the cellular regulation of vesicle exocytosis by entamoeba histolytica utilizing release of endocytosed 125iodine (125i) labeled tyrosine conjugated dextran; 125i-dextran entered the acid ph vesicles of the amebae and was not degraded during these studies. exocytosis was temperature dependent with 74%, 36%, 4%, and 0% of 125i-dextran released after 120 min at 37 degrees c, 31 degrees c, 25 degrees c, and 4 degrees c, respectively (p less than 0.01 for each). exocytosis at 37 degrees c ... | 1988 | 2452880 |
| evaluation of faecal preservation and staining methods in the diagnosis of acute amoebiasis and giardiasis. | the use of a faecal preservative and several staining methods, together with formalin ether concentration, were evaluated for the improved diagnosis of intestinal amoebiasis and giardiasis in 1285 patients with diarrhoea or dysentery and from asymptomatic controls. all samples were screened by three wet mount techniques. thirty eight specimens of diarrhoeal or dysenteric stool were preserved in polyvinyl alcohol (pva) and stained by trichrome and spencer and monroe short iron haematoxylin stain. ... | 1988 | 2454958 |
| secretory hydrolases of entamoeba histolytica. | cells of entamoeba histolytica grown over a period of four days contained nadp+-dependent alcohol dehydrogenase exclusively inside the cells. no activity of this enzyme could be found in the growth medium after harvesting the cells. under the same conditions, acid phosphatase, beta-n-acetylglucosaminidase, esterase, alpha-glucosidase, and different amylases of the parasite were found both inside the cells and in the medium. the activities present in the cell homogenate and in the medium before a ... | 1988 | 2456386 |
| bacterial, parasitic and viral enteropathogens associated with diarrhoea in saudi children. | in a 2-year study of stools from saudi children with gastro-enteritis and from controls, rotavirus was the pathogen most frequently detected, either alone (44.3%) or in combination with other enteropathogens (7%). there were two peaks for rotavirus isolates, one during the cold months and the other during the dry, hot season. salmonella spp. and campylobacter jejuni were the second and third most frequently isolated enteropathogens. enteropathogenic escherichia coli did not contribute significan ... | 1988 | 2456718 |
| pathogenic and non-pathogenic entamoeba: pore formation and hemolytic activity. | pore-forming activity in planar lipid bilayers and liposomes of extracts from differentially pathogenic entamoeba and the capacity of trophozoites and subcellular fractions to lyse human red blood cells (hrbc) were investigated. in all amebas studied, the two activities paralleled each other. they were high in e. histolytica irrespective of the virulence of the particular strain, but low in non-pathogenic e. histolytica-like amebas of human origin as well as in e. invadens, which is pathogenic f ... | 1988 | 2460621 |
| entamoeba histolytica: demonstration by pas/martius yellow technique. | | 1987 | 2460714 |
| biochemical and functional characterization of a membrane-associated pore-forming protein from the pathogenic ameboflagellate naegleria fowleri. | a membrane-bound cytolytic pore-forming protein (n-pfp) produced by the pathogenic ameboflagellate naegleria fowleri was characterized. n-pfp was solubilized from ameba membranes by detergent and enriched 300-fold by gel filtration chromatography. when analyzed by gel electrophoresis, n-pfp migrates with a molecular mass of 66 kda and 50-54 kda, under reducing and non-reducing conditions, respectively. in addition to lysing erythrocytes, n-pfp is cytotoxic to several tumor cell lines tested. its ... | 1989 | 2463245 |
| a specific solid-phase assay for the detection of immune complexes containing entamoeba histolytica antigens. | an assay specific for immune complexes containing entamoeba histolytica antigens has been developed. rabbit antibody specific for human gamma globulin is attached to a solid phase (nitrocellulose). during the first incubation step polyethylene glycol-precipitated immune complexes are bound to the rabbit antibody attached to the solid phase. in the second incubation step a radiolabelled rabbit antibody specific for entamoeba histolytica combines with e. histolytica antigens in the complexes. quan ... | 1989 | 2464037 |
| isolation, characterization and partial purification of a transferable membrane channel (amoebapore) produced by entamoeba histolytica. | entamoeba histolytica kills cells by contact dependent cytolysis. the mechanism underlying this process must be of rapid onset because target cells round up and show marked zeiosis within 15 min of contact. in earlier work, we identified a remarkable ion-channel forming protein which we named amoebapore, that may contribute to the amoeba-induced target cell killing. within the amoeba it exists as part of a supramolecular aggregate together with other proteins of unknown function. in this work we ... | 1989 | 2468084 |
| nucleic acids of entamoeba histolytica. | this review will concentrate on certain aspects of the nucleic acids of entamoeba histolytica. utilization and synthesis of purines and pyrimidines will initially be briefly discussed, e.g. salvage vs. de novo pathways, uptake studies and recognition of at least 4 transport loci. data will be presented which show that the distribution and synthesis of rna (to a lesser extent dna) in the nucleus is basically the opposite one finds in other eukaryotes, viz. most rna (ribosomal?) is synthesized (or ... | 1989 | 2470900 |
| pore-forming protein from entamoeba histolytica forms voltage- and ph-controlled multi-state channels with properties similar to those of the barrel-stave aggregates. | pore-forming protein from entamoeba histolytica forms cation-selective channels in planar bilayers. with increasing potentials, the open-state probability of these channels decreases, and channel aggregates collapse (young, j.d.-e. and cohn, z.a. (1985) j. cell. biochem. 29, 299-308). in this communication we report the following observations: (i) incorporation of the pore in black-lipid membranes was stimulated by membrane potential, (ii) pores were rectifying, (iii) breakdown of pores resulted ... | 1989 | 2472838 |
| total and specific ige in sera from patients with invasive amoebiasis. | total and specific ige antibodies were determined in 20 patients with invasive amoebiasis. using a histamine release assay by passive sensitized human leukocytes, a significant increase of entamoeba histolytica induced ige-mediated histamine liberation was found in basophils sensitized with sera from patients with amoebiasis as compared to those of control groups. concerning the total serum ige, no statistically significant changes were found in different serum groups. our results suggest that e ... | 1989 | 2474878 |
| sensitivity of protein and rna synthesis to antiamoebic drugs in axenic entamoeba histolytica (nih-200). | the action of antiamoebic drugs on the incorporation of (14c) 1-dl-valine and (14c)-8 adenine in tca insoluble fraction of axenic entamoeba histolytica was investigated. adenine showed greater sensitivity to all the drugs tested viz. camoquin, chloroquine, diodoquin, metronidazole, entobex and diloxanide furoate except enterovioform. | 1989 | 2476139 |
| use of wright's stain to identify entamoeba histolytica trophozoites in faeces. | | 1989 | 2481895 |
| phosphocholine epitopes on helminth and protozoal parasites and their presence in the circulation of infected human patients. | antigens containing phosphocholine (pc) circulate in the blood during chronic filarial infection. because of the wide occurrence of such pc epitopes, we examined their specificity by evaluating 10 common parasites of humans for the presence of pc epitopes, and sera from patients infected with these parasites for circulating antigens containing pc. immunoblot analysis of extracts from various parasites using an anti-pc monoclonal antibody (ca101) demonstrated the presence of pc epitopes on the pr ... | 1989 | 2482559 |
| [incidence of infection by intestinal parasites among school children in santiago, chile, 1988-1989]. | in december 1988-february 1989 period, a survey on enteroparasitic infections in children (mean age 8.7 years; males 54.4% and females 45.6%) from five schools located in santiago, chile, was undertaken. to each of these individuals, three samples were obtained in order to perform in them the following examinations: co-proparasitological study, modified ziehl-neelsen staining for detecting cryptosporidium sp. and cellulose adhesive test for enterobius vermicularis. parasitic elements were found ... | 1989 | 2484851 |
| [entamoeba histolytica stained with warthin-starry stain]. | the warthin-starry stain have been used for coloring a different microorganism like spirochetas, donovan bodies and campylobacter and also melanin granules demonstration in soft tissues tumors. we started using the stain, as we know it, in order to stain the histolytica amebas. we observed parasite stained black and brown as well as a good differentiation between endoplasm and ectoplasm where granular appearance, bacterial remnants and red cells were apparent. the stain was also usefull in diffe ... | 1989 | 2485237 |
| hepatic abscess among iraqi patients. | hepatic abscess was studied in 21 established cases in basrah hospitals (southern iraq) during 1985 to 1988. age of patients varied from 19 to 60 years. there were 7 females and 14 males and most of them from urban areas. all patients had a single abscess and the common site affected was the right lobe. microorganisms isolated from 19 patients included a variety of aerobic and anaerobic bacteria and a protozoan entamoeba histolytica. escherichia coli was the most common etiologic agent for the p ... | 1989 | 2513421 |
| [parasitic zoonoses in japan, with special reference to the current topics]. | the present situation of parasitic zoonoses in japan is reviewed. a total of 51 species, i.e., 6 species of protozoan parasites, 14 species of trematode parasites, 11 species of cestode parasites, 18 species of nematode parasites and 2 species of acanthocephalan parasites are potential zoonotic parasites. most (11 species) of the zoonotic nematodes provoke larva migrans. habitats of zoonotic parasites vary greatly depending upon individual species. some parasites cause heterotopic parasitism (e. ... | 1989 | 2513435 |
| chinese hamster ovary cells deficient in n-acetylglucosaminyltransferase i activity are resistant to entamoeba histolytica-mediated cytotoxicity. | to study the relationship between carbohydrate-specific amebic cytoadherence and ameba-mediated cytotoxicity, we measured entamoeba histolytica trophozoite-mediated cytolysis directed against a panel of four chinese hamster ovary (cho) cell lines that have defined alterations in their glycosylation patterns. we recently measured amebic trophozoite adherence to this panel of cho cells and showed that trophozoites bind variant cells (ricr 15b), which are deficient in asn-linked n-acetyllactosamine ... | 1989 | 2535835 |
| subunit structure of the galactose and n-acetyl-d-galactosamine-inhibitable adherence lectin of entamoeba histolytica. | the galactose and n-acetyl-d-galactosamine-inhibitable adherence lectin of entamoeba histolytica is a cell surface protein which mediates parasite adherence to human colonic mucus, colonic epithelial cells, and other target cells. the amebic lectin was purified in 100-micrograms quantities from detergent-solubilized trophozoites by monoclonal antibody affinity chromatography. the adherence lectin was purified 500-fold as judged by radioimmunoassay. the nonreduced lectin had a molecular mass of 2 ... | 1989 | 2536731 |
| effects of covalently bound silica-nitroimidazole drug particles on entamoeba histolytica. | most commonly used antiamoebic drugs are effective in invasive amebiasis, but their response against trophozoites of entamoeba histolytica, present in the lumen of the human colon, is inadequate. we report the development of an antiamoebic drug carrier that may be effective against luminal infections. our preparation consists of small silica particles (5-10 microns in diameter) covalently linked to a potent antiamoebic drug, 2-(4-aminophenoxymethyl)-5-nitro-1-methyl imidazole. silica-drug partic ... | 1989 | 2536782 |
| entamoeba histolytica: from adherence to enteropathy. | entamoeba histolytica, a cause of invasive colitis or liver abscess, is responsible for substantial worldwide morbidity and mortality. an understanding of the biochemical basis for the parasite adherence and cytolytic activities and antiamebic host immune response mechanisms are prerequisites for vaccine development. the e. histolytica galactose (gal) or n-acetyl-d-galactosamine (galnac) inhibitable adherence lectin mediates attachment of trophozoites to colonic mucins or mammalian target cells. ... | 1989 | 2536786 |
| dna probes specific for entamoeba histolytica possessing pathogenic and nonpathogenic zymodemes. | a number of dna probes which hybridize to highly abundant dna sequences of entamoeba histolytica were developed. variations in the hybridization patterns of different e. histolytica strains were detected with selected probes. four types of restriction fragment length patterns were obtained. of these, the first class belonged to e. invadens and e. histolytica-like var. laredo. the next two classes consisted of various strains of e. histolytica which were originally isolated from symptomatic patie ... | 1989 | 2537259 |
| parasitic, bacterial and viral pathogens isolated from diarrhoeal and routine stool specimens of urban bangladeshi children. | few data exist in bangladesh on longitudinal, community-based studies of bacterial or parasitic pathogens identified in routine and diarrhoeal stools of urban dwelling children. we undertook the following study on 343 children of age less than 6 years who resided in one of 51 slum settings in dhaka, bangladesh, between october 1984 and february 1986. specimens from diarrhoeal episodes and from routine stools obtained at 3-monthly intervals were examined for parasites, rotavirus and pathogenic ba ... | 1989 | 2537431 |
| antigenic stability and immunodominance of the gal/galnac adherence lectin of entamoeba histolytica. | immunoprecipitation of entamoeba histolytica proteins was performed with the sera of patients recovered from amebic liver abscess and colitis. the patients' amebic infection had been acquired in diverse areas of the world. the amebic galactose and n-acetyl-d-galactosamine-inhibitable adherence lectin was the major amebic antigen immunoprecipitated. the adherence lectin was recognized by all of the patients' sera tested regardless of the site (liver abscess vs. colitis) or geographic region that ... | 1989 | 2538054 |
| serologic response to the 96,000-da surface antigen of pathogenic entamoeba histolytica. | | 1989 | 2538522 |
| high seropositivity of japanese homosexual men for amebic infection. | | 1989 | 2538524 |
| proteinases of entamoeba histolytica associated with different subcellular fractions. | crude lysates of entamoeba histolytica (strain hm 1:imss) analyzed by substrate gel electrophoresis in 12.5% acrylamide separating gels with reducing agents showed six hydrolysis zones with apparent molecular weights of 73,000 (high), 45,000, 36,000 (intermediate), 30,000, 26,000 and 23,000 (low molecular weight proteinases). amebic lysates fractionated using the procedure of aley et al. or the procedure of rosenberg and gitler and analyzed by the same method show all enzymes in the fractions wi ... | 1989 | 2538746 |
| entamoeba histolytica ribosomal rna genes are carried on palindromic circular dna molecules. | highly abundant dna fragments obtained after restriction enzyme digests of nuclear dna of entamoeba histolytica strain hm-1:imss have been cloned and characterized. northern blot hybridization to e. histolytica rrna and sequence analysis identified the abundant dnas as ribosomal dna containing species. several overlapping clones containing these abundant dnas were isolated from 4 different genomic libraries of e. histolytica. alignment of the restriction maps was consistent with a circular molec ... | 1989 | 2538748 |
| specificity of a cysteine proteinase of entamoeba histolytica against various unblocked synthetic peptides. | the activity of highly purified cysteine proteinase of entamoeba histolytica against different peptides of the sequence x-gly-phe-phe was compared. the synthetic peptide arg-gly-phe-phe of the insulin b-chain was readily hydrolyzed yielding arg-gly and phe-phe as split products. lys-gly-phe-phe and tyr-gly-phe-phe were cleaved at rates of 20 and 4%, respectively. val-gly-phe-phe, gly-gly-phe-phe, glu-gly-phe-phe, and ser-gly-phe-phe were hydrolyzed at rates far below 1%. gly-arg-phe-phe, gly-phe ... | 1989 | 2539563 |
| ribosomal rna genes of pneumocystis carinii. | | 1989 | 2540326 |
| secretion of acid phosphatase by axenic entamoeba histolytica nih-200 and properties of the extracellular enzyme. | entamoeba histolytica (nih-200) secreted large amounts of acid phosphatase in its external environment when grown axenically in modified tps-ii medium. fractionation by deae-cellulose chromatography of the precipitate obtained from the cell-free medium at 60% ammonium sulfate saturation yielded 3 distinct peaks of enzyme activity. the enzyme in all the peaks showed resistance to tartrate but was inhibited by fluoride, cupric chloride, ethylene diamine-tetra acetic acid, ammonium molybdate and cy ... | 1989 | 2540328 |
| serological differentiation between zymodemes of entamoeba histolytica. | | 1989 | 2540346 |
| further characterization of a human monocyte locomotion inhibitory factor produced by axenically grown entamoeba histolytica. | | 1989 | 2540491 |
| nondysenteric intestinal amebiasis. colonic morphology and search for entamoeba histolytica adherence and invasion. | there is controversy regarding the presence of colonic mucosal abnormalities or mucosal invasion by entamoeba histolytica in patients with "nondysenteric intestinal amebiasis." to determine the role of e. histolytica in causing symptoms and mucosal changes and to detect if mucosal invasion by e. histolytica is present in nondynsenteric intestinal amebiasis, we evaluated 24 e. histolytica-infected patients (stool microscopy positive for e. histolytica) and 12 noninfected controls who presented wi ... | 1989 | 2540942 |
| cytokine activation of murine macrophages for in vitro killing of entamoeba histolytica trophozoites. | macrophage-mediated effector mechanisms against the protozoan parasite entamoeba histolytica were studied. unstimulated macrophages were inefficient at killing e. histolytica trophozoites in vitro and were killed by the trophozoites. conversely, immature cells of the mononuclear phagocyte lineage (promonocytes) were shown to display a strong spontaneous amebicidal activity. the acquisition of macrophage amebicidal activity following cytokine treatment was investigated. gamma interferon, tumor ne ... | 1989 | 2542164 |
| a military dependent with a hepatic mass. | | 1989 | 2542346 |
| dna hybridization probe for clinical diagnosis of entamoeba histolytica. | as an alternative to microscopic identification of entamoeba histolytica parasites isolated from stool, a sensitive and species-specific dna hybridization probe was made for rapid diagnosis of e. histolytica parasites in clinical samples directly applied to nylon membranes. the dna hybridization probe was made by screening a genomic library of a virulent hm-1:imss strain of e. histolytica to detect recombinant plasmids containing highly repeated parasite dna sequences. four plasmid clones that r ... | 1989 | 2542361 |
| indirect haemagglutination (iha) test in the serodiagnosis of amoebiasis. | among 72 patients clinically suspected of entamoeba histolytica (e. histolytica) infections, 39 positive cases (54%) were detected serologically by the indirect hemagglutination (iha) test. parasitologically, microscopic examination of three consecutive stool specimens from all these patients indicated positivity for e. histolytica cysts and or trophozoites in 10 of the patients with iha antibody titers greater than or equal to 1:128, which is of clinical significance. another 2 patients were pa ... | 1989 | 2542399 |
| pyogenic and amebic liver abscess. | amebic liver abscess is more common than pyogenic liver abscess on a global scale. in the united states, pyogenic liver abscess is more frequently seen. the epidemiology, etiology, microbiology, clinical features, natural history, diagnostic studies, and treatment of pyogenic and amebic liver abscess are discussed. | 1989 | 2542705 |
| delayed-type hypersensitivity to entamoeba histolytica in mice and hamsters: a comparison. | delayed-type hypersensitivity (dth) to live or fixed entamoeba histolytica was induced and compared in mice and hamsters. peak reactions were obtained 24 h post-challenge. in mice, challenge with 10(5) amoebae produced maximal, specific footpad swelling; in hamsters, 5 x 10(4) were required. elicitation of dth in mice was strongest 1 week after induction and remained comparatively high for 8 weeks. in hamsters, elicitability declined after 1-2 weeks. cyclophosphamide increased footpad reactions ... | 1989 | 2542927 |
| [invasive amebiasis with detection of entamoeba histolytica in rectal biopsies and liver abscesses]. | a 45-years old man after having returned from thailand was admitted to the hospital with a severe ulcerative, pyogenic colitis and multiple liver abscesses. in the endoscopically taken rectal biopsies as well as in the liver abscess aspirate gained by fine needle puncture throphozoites of e. histolytica could be demonstrated. on the other hand stool specimens and serology were negative. the various diagnostic facilities in invasive amebiasis are discussed. because of the problems, which may aris ... | 1989 | 2543150 |
| characterization of cell surface carbohydrate receptors for entamoeba histolytica adherence lectin. | binding and cytolysis of chinese hamster ovary (cho) cells by entamoeba histolytica trophozoites is inhibitable by galactose (gal) or n-acetyl-d-galactosamine (galnac). to better define the carbohydrate receptor for e. histolytica, we compared the binding and cytolytic target properties of 10 cho glycosylation mutants. each mutant expresses a uniquely altered array of n- and/or o-linked cell surface carbohydrates. amebic adherence was reduced when lactosamine-containing n-linked carbohydrates we ... | 1989 | 2543634 |
| cleavage of c3 by a neutral cysteine proteinase of entamoeba histolytica. | the major secreted proteinase of entamoeba histolytica, a 56-kda neutral cysteine proteinase, activates c by cleaving c3. the action of the proteinase is similar to c-derived c3 convertases because it produces a single cleavage of the alpha-chain in a dose- and time-dependent manner and cleaves c3 between residues 78 and 79, only one amino acid residue distal to the natural site acted on by the c3 convertases. c3a generation was detected by ria. the 105-kda fragment produced by the cleavage of t ... | 1989 | 2543700 |
| therapy of entamebiasis. | therapy of entamebiasis is critical in that, if untreated, the disease can be fatal. recently, a new method for differentiating pathogenic and non-pathogenic amebae has been standardized. this method relies upon the electrophoretic analysis of 4 isoenzymes which allow the identification of 20 different zymodemes. it is now widely accepted that non-pathogenic strains of entamoeba histolytica are not a hazard for humans and therefore don't need therapy. as a consequence, treatment must be addresse ... | 1989 | 2543800 |
| mechanism of innate immunity to amoebic infection in guineapigs. | the direct lymphocyte cytotoxicity and antibody dependent cell mediated cytotoxicity against entamoeba histolytica was studied in 3-4 wk old and 8-10 wk old guineapigs. both these parameters were significantly increased in splenic cells in the older animals. this might be due to maturation of the immune system or to natural infection by related parasite, leading to immunity. | 1989 | 2544516 |
| genomic dna differences between pathogenic and nonpathogenic entamoeba histolytica. | cdna libraries were constructed from pathogenic (hm-1:imss) and nonpathogenic (saw 1734) isolates of entamoeba histolytica. a cdna clone (ceh-p1) specific for pathogenic amoebae was identified by screening with a pool of sera from patients with invasive amoebiasis that had been absorbed with nonpathogenic amoebae. this clone was used for the identification of a homologous clone (ceh-np1) in the cdna from nonpathogenic amoebae. sequence analysis and comparison of the predicted amino acid sequence ... | 1989 | 2544890 |
| effects of gamma interferon on syntheses of dna and proteins by entamoeba histolytica. | to define the participation of cell-mediated immunity in resistance to amebic infection through the action of soluble mediators or lymphokines (lks), including gamma interferon (ifn-gamma), we studied their effect on entamoeba histolytica. supernatants from cultures of lymphoid cells, which had been stimulated in vitro with concanavalin a and were rich in lymphokines (lrsns), and recombinant ifn-gamma were used. lrsn and recombinant ifn-gamma inhibited the growth of e. histolytica trophozoites i ... | 1989 | 2547719 |
| amebic colitis masquerading as acute inflammatory bowel disease: the role of serology in its diagnosis. | amebic colitis needs to be considered in the differential diagnosis of infectious colitis or inflammatory bowel disease (ibd). misdiagnosing amebic colitis as idiopathic inflammatory disease may be fatal. although stool studies remain the initial approach to diagnosis, the incidence of false-negatives associated with this method is high. we report two cases of amebic colitis presenting as inflammatory bowel disease in which the diagnosis of amebic colitis was made by serology. neither patient ha ... | 1989 | 2547865 |
| human neutrophils activated by interferon-gamma and tumour necrosis factor-alpha kill entamoeba histolytica trophozoites in vitro. | the interaction between cytokine-activated human neutrophils and entamoeba histolytica trophozoites was studied as well as the mechanism(s) involved. treatment of neutrophils with rifn-gamma alone allowed them to kill 30% of e. histolytica trophozoites; however, rifn-gamma and rtnf-alpha pretreatments in combination increased neutrophil killing to 70%. in the absence of direct contact between neutrophils and amebae, rifn-gamma-treated neutrophils were shown to kill 70% of amebae, and rifn-gamma- ... | 1989 | 2547889 |
| chemoattractant activity of entamoeba histolytica for human polymorphonuclear neutrophils. | the ability of axenic entamoeba histolytica trophozoites and amoebic protein preparations to stimulate chemotaxis of human polymorphonuclear neutrophils (pmn) was evaluated. virulent e. histolytica (strain hm1:imss) stimulated chemotaxis (delta distance = 0.55 +/- 0.02 mm, p less than 0.01 vs. control medium). sonicated (100 micrograms protein/ml) or homogenized (500 micrograms protein/ml) virulent amoebae also significantly stimulated pmn chemotaxis, whereas preparations of the nonpathogenic "e ... | 1989 | 2547924 |
| unusual presentation of amoebic liver abscess. | two cases of amoebic liver abscess are described. the unusual, purely left pleuritic, presentation in the first patient is emphasised. amoebic liver abscess should still be thought of in any patient presenting with an acute febrile illness, upper abdominal and or thoracic manifestations and polymorphonuclear leucocytosis. such a consideration should obviate unnecessary morbidity, mortality and the injudicious use of ineffective therapeutic agents. | 1989 | 2548311 |
| [a new experimental model of cecal amebiasis in rats]. | the young rat was used as an experimental model of caecal amebiasis by implanting, without injury of the caecum, a suspension of e. histolytica trophozoites gnotoxenic strain rahman of high virulence. the degree of pathogenicity is demonstrated by the macroscopic aspect of caecum, by the density of trophozoites and by an anatomopathologic examination. as a correlation exits between all these macroscopic parameters and histology, a degree of illness is fixed which include several macro- and micro ... | 1989 | 2548430 |
| in vitro susceptibilities of entamoeba histolytica to azithromycin, cp-63,956, erythromycin, and metronidazole. | current therapy of entamoeba histolytica infection requires use of multiple agents effective at different body sites, including the intestinal lumen, intestinal tissue, and liver. azithromycin and cp-63,956, new extended-half-life macrolides which reach high levels in tissue, exhibit in vitro antiamebic activity at 18 or 48 h of incubation at concentrations comparable to that of erythromycin and slightly higher than that of metronidazole. azithromycin and cp-63,956 have the potential to be usefu ... | 1989 | 2548442 |
| [reliability of the pehps culture medium for the in vitro evaluation of antiamebic drugs]. | monophasic liquid media for axenical cultivation of entamoeba histolytica, have permitted to define diverse aspects of this parasite's biology, without associated organisms interference. in addition, these media have allowed the in vitro evaluation of new drugs with potential antiamebic properties. pehps, a new medium recently developed in our laboratory, was used in order to determine its usefulness in the searching for new antiamebic compounds. the antiamebic potency of currently employed drug ... | 1989 | 2548449 |
| [report on a fungus parasitizing entamoeba histolytica]. | infection of entamoeba histolytica with chytridiaceous fungus sphaerita was observed in some specimens obtained from a farmer and stained with iron-haematoxylin. the fungi were found in 78% of the cysts, mostly immature ones. within the amoebae this parasite occurred singly, in groups, or in the form of a sporangium. it was located in the cytoplasm, the glycogen mass or the chromatoidal bars. in the same specimen, the parasitic fungus was also found in 18% of e. coli cysts; in 11% of e. nana cys ... | 1989 | 2548767 |
| immunobiology of human infection by entamoeba histolytica. | | 1989 | 2549533 |
| isoenzyme analysis of entamoeba histolytica for evaluation of pathogenicity: detection of zymodeme xix in south america. | authors report the results of the isoenzyme analysis of strains of entamoeba histolytica isolated from international travellers. this recently developed method allows the detection of pathogenic strains by evaluating the electrophoretic mobility of cytoplasmic enzymes and was proved to be more reliable and quickly feasible than previous ones. the experience reported refers to three strains isolated from travellers coming from ecuador, brazil and indonesia, respectively; the zymodeme xix (in acco ... | 1989 | 2549611 |
| a simple spot-test for circulating entamoeba histolytica antigen-antibody complexes in patients with amoebic liver abscess. | an enzyme linked immunosorbent assay (elisa) is described for the detection of e. histolytica immune complexes in serum. antiamoebic antibody purified by affinity chromatography was used both to precoat strips of nitrocellulose membrane and as an enzyme carrier. these strips were incubated with samples of concentrated test serum and the enzyme conjugate. following treatment with the peroxidase substrate 3-amino-9-ethylcarbazole the presence of e. histolytica antigens was visualized as red spots. ... | 1989 | 2550365 |
| destruction of normal human eosinophils by entamoeba histolytica. | we evaluated the in-vitro interaction of normal human eosinophil leucocytes and a virulent strain of entamoeba histolytica (hm1-imss) in the presence of immune serum. at a 10:1 (eosinophil:amoeba) ratio a significant time-dependent destruction of eosinophils was found from the first hour onward, and a similar, albeit weaker, cytopathic effect was found in the 200:1 ratio mixtures, with some delay in the microscopic evidence of such effect. results were unaffected by serum factors, and amoebae em ... | 1989 | 2550874 |
| [a medium available in czechoslovakia for the culture of entamoeba histolytica and giardia intestinalis]. | from nutritive media produced in the cssr a modification of diamond's medium tyi-s-33 was prepared which ensures the long-term axenic cultivation of entamoeba histolytica and giardia intestinalis. details of the cultivation technique are also presented. | 1989 | 2551514 |
| interaction of different strains of entamoeba histolytica with target cells: characterization of electrophysiological and morphological features. | two strains of entamoeba histolytica with pathogenic zymodemes (sfl3, hk9), one strain with non-pathogenic zymodeme ("bru") and one non-pathogenic entamoeba sp. strain ("cold strain"), were investigated with respect to their interaction with target cells. three test systems were used: 1) direct microscopical observation and qualitative as well as quantitative evaluation of contact and binding events with mdck cells as targets, 2) kinetics of cytotoxic activity as measured by means of chromium re ... | 1989 | 2551817 |
| [amebic dysentery; diarrhea with blood and mucus urges to a study of the feces]. | | 1989 | 2552336 |
| lectins as cell recognition molecules. | lectins on cell surfaces mediate cell-cell interactions by combining with complementary carbohydrates on apposing cells. they play a key role in the control of various normal and pathological processes in living organisms. | 1989 | 2552581 |
| ultrastructure of experimental intestinal invasive amebiasis. | the morphological features of early intestinal ulcerations induced in rodents with axenic cultures of entamoeba histolytica were studied by scanning and transmission electron microscopy. amebas did not attach to the luminal surface of the mucosa except at interglandular regions, where parasites penetrated apparently through pseudopodial movement. once in the lamina propria, trophozoites multiplied and destroyed mucosal components. damage extended laterally through the mucosa, but progression to ... | 1989 | 2552849 |
| amebiasis now. | | 1989 | 2552852 |
| entamoeba histolytica depresses chemiluminescence in stimulated human polymorphonuclear leukocytes. | effect of entamoeba histolytica proteinase/toxin (ehp/t) on the luminol-dependent chemiluminescence (cl) in stimulated human polymorphonuclear leukocytes (pmn) was studied. the role of superoxide (so) and hydroxyl (oh) anions in the ehp/t-associated enhancement/inhibition of cl was also studied using specific scavengers and a biological response modifier, muramyldipeptide (mdp). ehp/t was isolated from axenic trophozoites of the hm-1:imss strain of virulent strain of e. histolytica. proteinase a ... | 1989 | 2553622 |
| circular dna of entamoeba histolytica encodes ribosomal rna. | the presence of repeated dna sequences encoding rna in entamoeba histolytica has been reported. in the present study we demonstrate by agarose gel electrophoresis. dnase digestion and electron microscopic analysis that these genes are located on extrachromosomal circular dna molecules with an approximate size of 26 kb. detection of replication intermediates suggests the episomal nature of these molecules. amplified, extrachromosomal rrna genes appear to be a common feature among the lower eukary ... | 1989 | 2553935 |
| [amebiasis. its epidemiology today]. | | 1989 | 2554461 |
| [amebiasis. features of its immunologic behavior]. | | 1989 | 2554462 |
| [amebiasis. has its clinical expression changed?]. | in mexico, like in other countries, there is an special interest for amebiasis because it represents a public health problem; there are about 5 million people that in some time of their lives had tissue invasion by this parasite. 1-2% of mexicanas have intestinal amebiasis and probably there are 850,000 to 1,700,000 carriers of entamoeba cysts. 6% of the general population have circulating antiameba antibodies. in 1988 we studied the amebic hepatic abscess seen in the hospitals of the instituto ... | 1989 | 2554463 |
| [amebiasis. the technology of the 80's. ii. studies of fecal material and serology for the diagnosis of amebiasis: have they helped improve the diagnosis of hepatic abscess?]. | | 1989 | 2554464 |
| coincidence of deficient delayed hypersensitivity and intestinal protozoa in homosexual men. | stool samples of 134 subjectively and apparently healthy male homosexual volunteers were studied, and in 86 men (64.2%) 190 parasite infestations, up to 6 per host, were identified. the most frequent species were endolimax nana (40), entamoeba coli (38), entamoeba histolytica (34), entamoeba hartmanni (32), and iodamoeba bütschlii (22); cryptosporidium was not found. all 11 isolates of entamoeba histolytica analysed belonged to a noninvasive zymodeme: 10 were of zymodeme i and i of zymodeme iii. ... | 1989 | 2555912 |
| cytologic detection of parasites in cervical smears. | | 1989 | 2555991 |
| thiol proteinase expression and pathogenicity of entamoeba histolytica. | expression of the 56-kilodalton (kda) neutral thiol proteinase has been shown to correlate with the potential of clinical isolates of entamoeba histolytica to produce invasive disease. a 56-kda band was identified by gelatin substrate gel electrophoresis in 10 of 10 isolates from patients with colitis or amebic liver abscesses, but in only 1 of 10 isolates from asymptomatic patients. pathogenic isolates appear capable of releasing significantly larger quantities of the proteinase, as measured by ... | 1989 | 2556432 |
| [results and experiences with several methods for the immunodiagnosis of amebiasis]. | results and experiences of some immunodiagnostic methods for amebiasis. experiences concerning the laboratory diagnosis of invasive amebiasis are described and discussed. technics used include the passive hemagglutination test with e. histolytica antigen (behring frg) and sheep erythrocytes as carrier and the indirect fluorescence antibody reaction (ifar) with corpuscular antigen prepared from cultures of e. histolytica strain hk 9. comparatively for a part infected hamster liver (dr. richle str ... | 1989 | 2556950 |
| action of the major protease from entamoeba histolytica on proteins of the extracellular matrix. | the action of the major protease from the parasitic protozoon entamoeba histolytica, a cysteine protease of mr 27,000-29,000, on some important proteins of the extracellular matrix has been studied. the isolated protease degraded the extracellular matrix proteins from human tissue collagen type iv and v as well as laminin and fibronectin with different velocities and specificities under native conditions. whereas the degradation of fibronectin and laminin proceeded rapidly, yielding distinct fra ... | 1989 | 2557443 |
| characterization of a cytochalasin d-resistant mutant of entamoeba histolytica. | characterization of a cytochalasin d-resistant mutant of the human parasite entamoeba histolytica capable of growing at 10 microm cytochalasin is described. the mutant cells also show resistance to 5 mm colchicine and 100 microm cytochalasin b, drugs proved deleterious for wild type trophozoites. the mutants show increased osmotic fragility and electric mobility but reduced phagocytic activity, and agglutination by concanavalin a. on the other hand pinocytic activity remains unaltered when compa ... | 1989 | 2557444 |
| breakdown of glucopolysaccharides in entamoeba histolytica by phosphorylase. | homogenates of trophozoites of entamoeba histolytica released glucose 1-phosphate from amylopectin, glycogen, and amylose in a ratio of 100:78:74 at glucopolysaccharide concentrations of 0.1%. by use of self-generating percoll gradients this activity was shown to be particulate and associated with glycogen. the phosphorylase was extracted from the 40,000 g pellet in aqueous medium and purified to homogeneity by gel filtration on fractogel tsk hw-55(f) followed by chromatography on blue sepharose ... | 1989 | 2557445 |
| magnetic separation of pinocytic vesicles of defined age from entamoeba histolytica. | we describe a rapid and simple method to isolate pinocytic vesicles of defined age (residing time within the cell) from entamoeba histolytica. amoebas are allowed to pinocytize for greater than 5 min a suspension of superparamagnetic iron oxide particles, washed, and resuspended for predetermined periods (up to 150 min) in iron oxide-free medium. subsequently, the cells are homogenized and iron oxide-containing vesicles are separated magnetically. recovery of vesicles (estimated with fluorescein ... | 1989 | 2557779 |
| detection of entamoeba histolytica trophozoites in liver pus by the indirect fluorescent antibody test for the aetiological diagnosis of amoebic liver abscess. | the indirect fluorescent antibody test was used to detect trophozoites of entamoeba histolytica in liver pus aspirated from patients with amoebic liver abscess. the test can be carried out in no more than two hours. trophozoites with fluorescence were observed in 17 of the 18 patients with amoebic liver abscesses who were studied. cells with fluorescence were not found in any negative control specimens from patients with bacterial liver abscess, primary liver cancer, cirrhosis or tuberculous per ... | 1989 | 2557802 |
| evidence for selection of virulent sub-populations of entamoeba histolytica by cholesterol. | quantitatively much higher concanavalin a (con. a) agglutinability, haemolytic potency, and activities of acid hydrolases, namely phosphatase (ec 3.1.3.2), ribonuclease (ec 2.7.7.16), deoxyribonuclease (ec 3.1.4.5) and proteinase--were observed in a virulent strain of entamoeba histolytica (ip-106), as compared to attenuated and avirulent strains (200-nih) and dkb respectively. in addition, significant differences in these parameters were observed among clonal cultures derived from the latter tw ... | 1989 | 2557803 |
| demonstration of histamine receptors on the surface of entamoeba histolytica. | histamine receptors on the surface of e. histolytica could be demonstrated by histochemical method using three isolates of the protozoa grown and maintained in modified boeck and drbohlav's medium. prior treatment of e. histolytica with cimetidine a h2 blocker, blocked the histamine uptake. similar treatment with mepyramine maleate, a h1 blocker, did not prevent histamine uptake by the protozoa. it is postulated that e. histolytica has h2 receptors on its surface. | 1989 | 2558075 |
| two rapid and simple enzyme immunoassays for human antibodies to entamoeba histolytica. | two rapid and simple enzyme immunoassays (eia) for antibodies to e. histolytica the protozoa causing ambiasis, are described. in the rapid dot eia, a qualitative procedure, antigens were dried as a small dot (3 mm in diameter) on a thin white opaque polystyrene strip and serum samples were assayed undiluted. the assay required 3 incubation periods, 1 to 3 minutes each, and was completed in 9 minutes, with a positive reaction revealed as a blue color (precipitate) on the antigen dot and negative ... | 1989 | 2558127 |
| presence of a fructose-2,6-bisphosphate-insensitive pyrophosphate: fructose-6-phosphate phosphotransferase in the anaerobic protozoa tritrichomonas foetus, trichomonas vaginalis and isotricha prostoma. | extracts of the anaerobic protozoa tritrichomonas foetus, trichomonas vaginalis and isotricha prostoma contained a high activity (0.5-1 mumol min-1 (mg protein)-1) of pyrophosphate:fructose-6-phosphate phosphotransferase (ppi-pfk), but no detectable atp: fructose-6-phosphate phosphotransferase. ppi-pfk from i. prostoma was purified close to homogeneity by adsorption on phospho-ultrogel and elution with fructose-1,6-bisphosphate, and subsequent anion-exchange chromatography. the enzyme had an mr ... | 1989 | 2558319 |
| suitability of the phast system for discrimination of entamoeba isolates by isoenzyme isoelectrofocusing. | | 1989 | 2558434 |
| [laboratory diagnosis of entameba histolytica]. | | 1989 | 2559004 |
| entamoeba histolytica and other parasitic infections in south kanara district, karnataka. | single stool specimens collected from 1,020 apparently healthy people of the south kanara district, were processed for intestinal parasites using three parasitological methods viz. (a) direct smear in physiological saline and d'antoni's iodine, (b) zinc sulfate concentration method and (c) by culture in modified boek and drbolhav medium. of these 781 (76.51 per cent) were found to be infected with parasites. the prevalence of various intestinal parasites was: ascaris lumbricoides (48.33 per cent ... | 1989 | 2559118 |
| a simple micropore system for experimental studies on trichomonad parasites. | a simple leak-free micropore chamber containing protozoan parasite species was implanted subcutaneously on the back of hamsters and evaluated for viability and multiplication of protozoan parasites. trophozoites of defined strains of entamoeba histolytica, giardia lamblia, trichomonas vaginalis, and tritrichomonas foetus were used; their survival and multiplication in the chambers formed the basis of evaluation. entamoeba histolytica and g. lamblia did not survive more than 6 hr and succumbed du ... | 1989 | 2559180 |
| entamoeba histolytica: molecules involved in the target cell-parasite relationship. | to detect molecules of entamoeba histolytica involved in the trophozoite-target cell interaction, three different antisera were generated: (a) two rabbit antisera, one against total amebic proteins and another directed specifically to the 112-kda adhesin; and (b) a mouse antiserum against amebic molecules adhering to the red blood cell (rbc) surface after incubation of rbcs with total soluble protein from trophozoites (anti-adhesion serum). all three antisera recognized the 112-kda adhesion. adh ... | 1989 | 2559329 |
| in vitro activity of nalidixic acid and its iron (iii) complex on entamoeba histolytica. | the in vitro activity of the antibacterial agent nalidixic acid (hnal) and its iron (iii) complex (fenal) against entamoeba histolytica hm1 strain trophozoites in axenic or monoxenic (associated with clostridium symbiosum) cultures was investigated. using a dilution test with tyi-s-33 medium, this protozoan was found to be susceptible to both drugs, but fenal showed amoebicidal activity only at concentrations higher than those used with hnal. | 1989 | 2559504 |
| kinetics of the immune responses during the course of hepatic amoebic infection--an experimental study. | following intrahepatic inoculation of axenic entamoeba histolytica (strain nih:200v), all hamsters developed amoebic abscesses in the liver by 7 d after inoculation. all the animals cleared the infection spontaneously by 28 d after inoculation. the establishment of amoebae leading to acute liver abscess was accompanied by significantly reduced levels of antibodies to the plasma membrane (pm) protein of e. histolytica, reduced direct macrophage cytotoxicity, and reduced anti-pm antibody-mediated ... | 1989 | 2559505 |
| high susceptibility of five axenic entamoeba histolytica strains to gossypol. | the antiamoebic potency of gossypol was tested against 5 axenic entamoeba histolytica strains, in logarithmic phase growth in pehps medium. all of the strains were moderately susceptible to this polyphenolic drug. the 50% inhibitory concentration (ic50) was of the same order of magnitude in all strains: 0.015 microm (for strain hm-1) to 0.067 microm (for hm-38). the difference between the ic50 of hm-1 and the remaining 4 strains (hm-38, hk-9, hm-2 and hm-3) was significant, although it was great ... | 1989 | 2559507 |
| pathogenic zymodemes of entamoeba histolytica in japanese male homosexual population. | | 1989 | 2559508 |