| entamoeba histolytica: recognition of alpha- and beta-galactose by the 260-kda adherence lectin. | | 1991 | 1993459 |
| giardiasis and amoebiasis infections in three saudi closed communities. | two hundred and eighteen residents (131 healthy and 87 mentally or physically retarded) of a children's nursery, a foster house and a rehabilitation centre for the handicapped in abha, southwestern saudi arabia, were examined for intestinal parasitism. about 30% of the population of the three communities were found to harbour asymptomatic infections with either giardia lamblia and/or entamoeba spp. giardia cysts were identified in 19.3% of those examined. entamoeba histolytica was found in 18.4% ... | 1991 | 1995937 |
| entamoeba histolytica infection and aids. | | 1991 | 1996598 |
| primary structure of the 170-kda surface lectin of pathogenic entamoeba histolytica. | the adherence of entamoeba histolytica to colonic mucins and to host cells appears to be predominantly mediated by a 170-kda surface lectin of the amoebae. by using an antiserum to the purified lectin, the corresponding cdna was isolated from an expression library of the pathogenic e. histolytica isolate hm-1:imss. northern blot analysis indicated a transcript of approximately 4 kilobases, and southern blot analyses suggested that multiple genes may encode the lectin or closely related proteins ... | 1991 | 2000392 |
| mucin and nonmucin secretagogue activity of entamoeba histolytica and cholera toxin in rat colon. | depletion of colonic mucus occurs before invasion of the colonic mucosa by entamoeba histolytica trophozoites. it is hypothesized that e. histolytica releases a mucus secretagogue; this was studied in a rat colonic loop model. in colonic loops exposed to live amebae, mucus secretion was quantitated by release of acid-precipitable [3h]glucosamine-labeled luminal glycoprotein and by specific immunoassay. mucus secretion increased in dose-dependent fashion in response to greater than or equal to 1 ... | 1991 | 2001836 |
| cloning and characterization of an unusual elongation factor-1 alpha cdna from entamoeba histolytica. | the coding sequence deduced from two overlapping cdna inserts obtained from a pathogenic strain of entamoeba histolytica revealed a striking homology (greater than 85%) with elongation factor ef-1 alpha from saccharomyces cerevisiae and artemia salina. the deduced amino acid sequence predicted a size of 49 kda, and antibodies raised against the s. cerevisiae ef-1 alpha cross-reacted with an amoebic protein of similar size (45-47 kda). sequence analysis of the cdna revealed that the 5' untranslat ... | 1991 | 2011152 |
| sexually transmitted parasitic diseases. | sexual activity is the primary method of transmission for several important parasitic diseases and has resulted in a significant prevalence of enteric parasitic infection among male homosexuals. the majority of parasitic sexually transmitted diseases involve protozoan pathogens; however, nematode and arthropod illnesses are also included in this group. trichomoniasis, caused by trichomonas vaginalis, is the most common parasitic std. infection with this organism typically results in the signs an ... | 1991 | 2011632 |
| increased frequency of hla-dr3 and complotype sc01 in mexican mestizo patients with amoebic abscess of the liver. | our preliminary study (31 patients) of hla frequencies and amoebic abscess of the liver (aal) in mexican mestizos was extended to include 110 patients with this condition. the previously found increase in hla-b16 was not confirmed, but the frequency of hla-dr3 was again found significantly increased in patients with aal when compared to the normal, ethnically matched control population, both in its isolated (35.5% vs 12.7%) and in the hla-a2, dr3 haplotypic version (20.9% vs 4.5%). moreover, sev ... | 1991 | 2014135 |
| immunoprecipitation studies with biotinylated entamoeba histolytica antigens. | the biotinylation of protein antigens for use in immunoprecipitation studies with parasite antigens is described. this technique was standardized to produce maximal labelling without compromising either the viability of the parasite or the antigenicity of labelled proteins. live axenic entamoeba histolytica trophozoites were optimally labelled by incubation of 10(7) parasites in 1 ml phosphate-buffered saline for 20 min at 37 degrees c with a final concentration of 10 mm n-hydroxy succinimido-bi ... | 1991 | 2014137 |
| sequence of a cysteine-rich galactose-specific lectin of entamoeba histolytica. | entamoeba histolytica trophozoites adhere to human colonic mucins and epithelial cells by a cell surface galactose-specific lectin. this lectin, which is composed of two subunits linked by disulfide bonds, has been shown to be a protective antigen in an animal model of amebiasis. we have determined the sequence of the mature form of the 170-kda heavy subunit from cdna clones and pcr-amplified fragments. the heavy subunit sequence consisted of a putative extracellular domain containing 1209 amino ... | 1991 | 2014248 |
| entamoeba histolytica: generation and characterization of hybrid clones. | transference of dna to entamoeba histolytica was carried out by polyethylene glycol fusion of two amebic clones with different phenotypes. clone c9, strain hm1:imss, was the donor. it is emetine-resistant, highly phagocytic and virulent, and grows in soft agar. clone l6, strain hm1:imss, the recipient, is emetine-sensitive, phagocytic, and virulence-deficient, and it does not grow in soft agar. clones l6 and c9 have shown high stability in their virulence phenotypes since their isolation more th ... | 1991 | 2015865 |
| intestinal parasites in cambodians: comparison of diagnostic methods used in screening refugees with implications for treatment of populations with high rates of infestation. | we performed a retrospective review of screening parasitology examinations on a cambodian refugee population served by an urban neighborhood health center. five-hundred twenty of 1084 patients were examined for ova and parasites either by purged stool, which was examined immediately, or preserved stool, examined at a teaching hospital and proprietary laboratories. overall, 335 (64 percent) of the tested patients had at least one parasite. the prevalence of infection varied by test technique (pur ... | 1991 | 2028827 |
| fulminant amebic colitis. | amebiasis is the acute and chronic disease produced by entamoeba histolytica, an entity which occurs in endemic fashion in many of the tropical and subtropical areas of the world, capable of affecting diverse organs of the body, especially the colon. amebiasis has different clinical forms of presentation, varying from the asymptomatic carrier state to severe, although not frequent, fulminant or necrotizing colitis, characteristically associated with high morbidity and mortality. we hereby report ... | 1991 | 2031357 |
| surgical complications of ascariasis. | over the past 25 years (1963-1988), a total of 311 children under 12 years of age were admitted to the pediatric surgical service of the san vicente de paúl university hospital, medellín, colombia, with complications resulting from infection with entamoeba histolytica or ascaris lumbricoides. in this group, the abdominal complications produced by ascariasis numbered 145, and included intestinal obstruction (n = 107), perforation of the appendix (n = 10), and migration of the parasite to the bili ... | 1991 | 2031358 |
| infectious diarrhea. | this review singles out several bacterial and parasitic causes of infectious diarrhea about which there have been interesting recent developments in pathogenesis, diagnosis, or treatment. diarrheagenic mechanisms and infections by escherichia coli, salmonella, giardia lamblia, entamoeba histolytica, cryptosporidia, and isopora are discussed. | 1991 | 2035985 |
| amebic liver abscess: a 15-year experience. | amebic liver abscess is increasingly common in the united states, particularly in the west and southwest, due to increased immigration from southeast asia, mexico, and central america. the presentation, course, and treatment of 50 patients treated for amebic liver abscess at a county-community hospital in san jose, california, between 1974 and 1988 is reviewed. the typical patient is an immigrant, usually a hispanic male, 20-40 yr old, who presents with fever, right upper quadrant pain, leukocyt ... | 1991 | 2038992 |
| intestinal parasites in a rural community in kenya: cross-sectional surveys with emphasis on prevalence, incidence, duration of infection, and polyparasitism. | a cross-sectional survey of intestinal parasitic infection in a rural community, nderu, in kiambu district, kenya, was carried out in 1985 by examining 1129 individuals from 203 households (about 25% of the total population). this was followed by 3 more cross-sectional surveys, in january, may and october 1986, of 56 families comprising 461 individuals, who had also participated in the first survey. in the first survey, 81.4% of the sample was positive for at least one intestinal parasite and 78 ... | 1991 | 2040230 |
| sequence analysis of a dna fragment with yeast autonomously replicating sequence activity from the extrachromosomal ribosomal dna circle of entamoeba histolytica. | | 1991 | 2041750 |
| role of leukocytes and amebic proteinases in experimental rat testicular necrosis produced by entamoeba histolytica. | to investigate the role of amebic proteinases and host leukocytes, we studied amebiasis experimentally in the rat testis. the degree of inflammation and necrosis produced by different strains was correlated with proteinase activity and with zymograms. intratesticular injection of axenically grown trophozoites of a pathogenic strain (hm-1 of entamoeba histolytica) produced indistinguishable lesions in normal animals and leukopenic rats (less than 1000 leukocytes/mm3), suggesting that granulocytes ... | 1991 | 2047366 |
| mass treatment of intestinal parasites among ethiopian immigrants. | intestinal parasites are common among the ethiopian immigrants to israel and mass treatment is necessary to prevent local transmission. for this purpose, stool samples obtained from the immigrants in absorption centers were examined. of 5,412 samples obtained, 4,399 (81.3%) were positive: 2,644 (54.2%) for necator americanus, 2,273 (46.6%) for schistosoma mansoni, 990 (20.3%) for ascaris lumbricoides, 1,040 (21.3%) for hymenolepsis nana, 940 (19.2%) for trichuris trichiura, 219 (4.5%) for strong ... | 1991 | 2050509 |
| chromatin organization in entamoeba histolytica. | the chromatin structure of entamoeba histolytica was investigated. it was found that this protozoan organizes its chromatin in nucleosome-like particles 10 nm in diameter, but digestion of the chromatin with micrococcal nuclease did not render a regularly spaced dna ladder in agarose gels. southern blot analysis of the products of entamoeba chromatin digestion using total amebic dna and a non-transcribed repetitive sequence produced a banding pattern characteristic of eukaryotic chromatin with a ... | 1991 | 2052032 |
| detection of hiv-1 in entamoeba histolytica without evidence of transmission to human cells. | intestinal protozoa like entamoeba histolytica and giardia lamblia have been proposed as vectors or cofactors in the development of aids. to determine whether these protozoa could transmit hiv, laboratory strains of protozoa were cocultured with cells chronically infected by a highly replicative strain of hiv-1. entamoeba histolytica, but not giardia lamblia, took up virus. immunologically detectable hiv-1 was present in the amebae up to 48 h after exposure to infected cells, but this virus coul ... | 1991 | 2059366 |
| [histopathology of experimental hepatic amebiasis]. | the method of intrahepatic inoculation was successfully used to establish an experimental model of hepatic amebiasis in golden hamsters for studying its pathological morphology. three types of macroscopic liver lesions, i.e., isolated abscess, multinodular abscess and ruptured lesion were described. on light microscopy the alteration and the proliferation type lesions were found as distinct pathological characteristics of the early and advanced hepatic amebiasis respectively. the development pat ... | 1991 | 2065451 |
| [fundamental study on serological diagnosis of amoebiasis. 3. serological survey of amoebiasis in blood donors showing seropositive for syphilis]. | sera of 375 blood donors which were seropositive for syphilis were examined for antibodies against entamoeba histolytica. antibody prevalences against e. histolytica using complement fixation (cf) test were 12.0%, and enzyme-linked immunosorbent assay (elisa) were 2.7%. the positive rates of antibodies in the cf test were significantly higher in sera showing positive by the venereal disease research laboratory (vdrl) test than in the vdrl-negative sera, and not related to the results of treponem ... | 1991 | 2066582 |
| phagocytosis of human erythrocytes by naegleria is not related to species pathogenicity. a phase-contrast cinemicrographic study. | this phase contrast cinemicrographic study evaluated the phagocytic activity of naegleria spp. (naegleria fowleri, naegleria australiensis and naegleria lovaniensis) towards human red cells. thus erythrophagocytosis, a marker of pathogeneicity for entamoeba histolytica, did not correlate with virulence in either the pathogenic or non-pathogenic naegleria spp. tested. our study also revealed no quantitative differences in phagocytosis by naegleria spp. of human erythrocytes. | 1991 | 2067415 |
| antibodies to gut protozoa in commercial immunoglobulin preparations. | using parasite agglutination, indirect immunofluorescence, enzyme-linked immunosorbent assay, and immunoblotting, giardia lamblia specific antibody was detected in 5 commercially available immunoglobulin (igg) preparations. igg antibodies to entamoeba histolytica were either present in very low titre or were absent. immunoblotting showed that anti-g. lamblia antibodies were detected towards a range of giardia proteins, 25-200 kda. these findings raise the possibility that pooled human igg prepar ... | 1991 | 2068767 |
| the effect of immunosuppressive and immunostimulatory treatment on experimental amoebiasis. | immunosuppressive treatments consisting of ionizing irradiation or drugs were employed in inbred and outbred mice and in golden hamsters. following treatment, mice were challenged intracaecally or intrahepatically with virulent, axenically-grown entamoeba histolytica. hamsters were challenged by intraperitoneal injection of the amoebae. many of the experimental animals died of the combined effects of treatment and challenge. mice remained essentially refractory to infection with e. histolytica r ... | 1990 | 2076035 |
| comparative study of aminosidine, etophamide and nimorazole, alone or in combination, in the treatment of intestinal amoebiasis in kenya. | 417 patients suffering from intestinal amoebiasis were randomly allocated to 6 different treatment groups in a controlled study in 3 district hospitals in kenya. the patients received either aminosidine (a), etophamide (e), nimorazole (n), or the combinations na, ne, ea. treatment in all cases was given twice daily for 5 days. before and after treatment, rectosigmoidoscopy was done in each patient, and stool examination with characterization of invasive (if) and non invasive (nif) forms of amoeb ... | 1990 | 2076717 |
| six enteropathogens isolated from a case of acute gastroenteritis. | isolation of six different gastrointestinal pathogens (entamoeba histolytica, plesiomonas shigelloides, campylobacter jejuni and three different salmonella species [salmonella typhimurium, salmonella blockley and salmonella hadar]) in the feces of a german female tourist suffering from acute diarrhoea after a trip to bali. | 1990 | 2076911 |
| [intestinal parasites and lactose malabsorption]. | breath-test was performed for diagnosis of lactose malabsorption in 50 gabonese children of normal nutritional status, aged 5 to 15 years, with parasites in stools, but without diarrhoea or digestive symptoms. control group was unparasitized and consisted of 17 children and 18 young adults living in the same area. parasites discovered by stool examination were ascaris lumbricoides in 76% of parasitized children, trichuris trichiura in 58%, giardia in 24%, entamoeba histolytica in 20%, schistosom ... | 1990 | 2078108 |
| glutathione transferase activity in some flagellates and amoebae, and purification of the soluble glutathione transferases from acanthamoeba. | glutathione transferase (gst) enzymes are toxicologically important from many points of view. nine protozoans were investigated here for their gst content. six aerobic amoebae had very different specific gst activities, but an anaerobic amoeba and two anaerobic flagellates did not have any gst activity, suggesting that the peroxidase activity of gst is an evolutionarily important property for aerobic organisms. the soluble gst isoenzymes of acanthamoeba culbertsoni and a. polyphaga were purified ... | 1990 | 2078188 |
| prevalence of salmonella, shigella and intestinal parasites in food handlers in irbid, jordan. | during a one-year period, 283 food handlers in irbid, jordan were investigated for the presence of potential enteropathogens in their stools. the prevalence rate of enteropathogens among non-jordanian food handlers (48.0%) was significantly higher (p less than 0.05) than that of the jordanian group (12.3%). the isolation rates of salmonella and shigella were 6% and 1.4% respectively. multi-drug resistance was frequent among isolates of salmonella group b and shigella spp. intestinal parasites de ... | 1990 | 2081882 |
| immunoreactivity of entamoeba histolytica antigens with sera from amoebic patients. | immune sera from 15 patients with cured amoebic liver abscess were used to recognise the antigens of entamoeba histolytica (hmi) by immunoblotting. the amoebic proteins most frequently recognised by sera from patients with cured amoebic liver abscess had molecular masses of 8, 13, 18, 22, 29, 38, 45, 67 and 94 kda. six plasma membrane-associated amoebic proteins of molecular mass 29, 38, 45-67 complex, 85 and 94 kda were strongly recognised by such sera. two plasma membrane-associated antigens o ... | 1990 | 2082159 |
| identification of protein kinase c and its potential substrate in entamoeba histolytica. | 1. protein kinase c (pkc) activity has been identified in various strains of the human parasite, entamoeba histolytica. 2. an amoebic protein of mol. wt 78,000 was recognized by polyclonal antibodies raised against the 82,000 mol. wt rat brain protein kinase c. 3. a partially purified pkc preparation from e. histolytica phosphorylated histone i in the presence of calcium, phospholipids and diacylglycerol, and specifically bound tritiated phorbol ester at an apparent kd of 9 nm. 4. a relocalizati ... | 1990 | 2085954 |
| detection of glycogen-debranching system in trophozoites of entamoeba histolytica. | homogenates of trophozoites of entamoeba histolytica were shown to bring about the total degradation of glycogen while purified phosphorylase of the same source alone yielded a limit dextrin as end product. an enzyme system capable of debranching the limit dextrin was obtained from the 40,000 g pellet by extraction in aqueous medium, purified by gel filtration on fractogel tsk hw-55(f), and separated from phosphorylase by chromatography on blue sepharose cl-6b and aminobutyl agarose. the glycoge ... | 1990 | 2086786 |
| [a survey of the current status of the differential diagnosis of amoebas in mexico]. | the differential diagnostic criteria for the amebas parasitizing the human colon are described. the results of epidemiological studies carried out published in mexico are discussed and the results of a survey performed in some hospitals in mexico city on the current differential diagnosis of these parasites are reported. the findings showed that no carriers of e. hartmanni have been reported in the studies published in mexico so far. however, no differentiation between e. histolytica and e. hart ... | 1990 | 2089634 |
| ruptured amebic liver abscess. | we treated two patients with a ruptured amebic liver abscess. the diagnosis was made at a relatively early stage and treatment was successful for one patient, but an accurate diagnosis of liver abscess was not made and invasive extraintestinal amebiasis led to multiple organ failure and to death for the other. neither patient had been outside of japan, and both were heterosexual. the origins of entamoeba histolytica infection could not be determined. though the mortality rate is high in cases of ... | 1990 | 2090186 |
| [prevalence of entamoeba histolytica and other intestinal parasites in a neighborhood of the mara municipality, zulia state, venezuela]. | a parasitologic survey of a low socioeconomic level community from mara county, zulia state, venezuela was done. a single stool specimen per person from 327 individuals was obtained and examined by hematoxylin stained fecal smears and formol-ether concentrates. the overall parasitic infection rate was 92%. multiple infections were present in 89% of the population. the amebic prevalence rate (apr) was 41.5%. entamoeba histolytica was found in 9.2% of the individuals, most of them being asymptomat ... | 1990 | 2090263 |
| molecular karyotype of entamoeba histolytica and entamoeba invadens. | we report the size-fractionation of entamoeba histolytica and e. invadens deoxyribonucleic acid (dna) by pulsed field gradient electrophoresis. using 3 different electrophoretic conditions, we were able to resolve 6 to 9 bands between 300 and 2000 kilobases (kb), distributed in 16-22 large and up to 31 small chromosomes for e. histolytica dna. for e. invadens, 4 to 5 bands between 300 and over 2000 kb were resolved and discriminated in 4 large and 6 small chromosomes. a ribosomal probe from tryp ... | 1990 | 2091349 |
| [massive production of entamoeba histolytica cysts under axenic conditions]. | after an exponential phase of growth, hk9 strain amebas, kept in the axenic medium pehps, spontaneously acquire a form morphologically similar to various natural cysts, as well as a resistance to hypotonic shock, due to the effect of a wall, partially composed of polysaccharides. the number of differentiated amebas increases gradually, although their viability diminishes, in function of the incubation time. on the ninth day, 96% of the population is made up of these cells, although only 6% are v ... | 1990 | 2093567 |
| entamoeba histolytica infections in flight personnel of an international airline. | a cohort of 99 subjects, members of the flight staff of lufthansa german airlines, all infected with entamoeba histolytica, were followed over a period of 2.5 years to monitor their clinical and parasitological status. all but 4 of the subjects were infected with non-pathogenic zymodemes of e. histolytica and had negative amoebic serology, and most were clinically well. one male heterosexual carrying a pathogenic zymodeme was found, despite massive treatment regimes, to carry the infection persi ... | 1990 | 2096512 |
| pathogenic zymodemes of entamoeba histolytica remain unchanged throughout their life-cycle. | | 1990 | 2096514 |
| purification and characterization of e. histolytica antigen for diagnosis of amoebiasis. | entamoeba histolytica soluble crude antigen was fractionated by gel filtration on sephacryl s-300 into four fractions, viz. f1(669 kda); f2(51.2 kda); f3(25.1 kda) and f4(10.5 kda). f1 fraction was observed to be more sensitive and specific for the detection of antibody in amoebiasis than the crude and other fractions of purified antigens employing ihat and elisa. elisa was found to be better than ihat since it could detect antibody in the sera (3/6) of asymptomatic cyst passers. the cross react ... | 1990 | 2099326 |
| etiological agents of diarrhoea. | two decades of research have established newer pathogens and techniques in establishing several organisms of diarrhoeal diseases as aetiological agents. it is now possible to detect an agent in 80% of the situation of diarrhoea in a standard laboratory. the brief review describes the list of pathogens, their diagnostic techniques with short description on clinical and epidemiological status. | 1990 | 2101388 |
| a profile of diarrhoea in an urban slum area. | researchers followed 90 households (445 people) in sunderpur slum in varanasi in upper pradesh, india for 1 year and collected stool samples when people were ill with diarrhea to determine diarrhea incidence and causes of diarrheal disease. the water supply consisted of a well, public tap, or house tap with 30 households in each group. they noted 106 diarrheal episodes for an incidence of around 23%. incidence decreased significantly with age (p.001). for example, it was 62.9% for children 5 ... | 1990 | 2101391 |
| helminths and protozoa as an incidental finding in cytology specimens. | this is a description of some helminths and protozoa found incidentally in routine cytology specimens submitted to this laboratory. eight different organisms are described together with the case history for each patient. all the specimens were stained with papanicolaou technique. | 1990 | 2102355 |
| counterimmunoelectrophoresis in the immunodiagnosis of amoebiasis. | counterimmunoelectrophoresis (cie) detection of antiamoebic antibodies in the patients' sera, has been carried out and correlated with the routine diagnostic microscopic examination of stool and pus samples. the clinically suspected amoebiasis cases were divided into two main groups, (i) proved positive for entamoeba histolytica as detected by microscopic examination of samples, and (ii) negative for the parasite. a total 153 cases of intestinal amoebiasis were studied. cie was positive in 27 of ... | 1990 | 2102909 |
| causative agents of acute diarrhoea in the first 3 years of life: hospital-based study. | during the 2 years of the study, 402 patients and an equal number of age- and sex-matched controls were investigated for the presence of diarrhoeal pathogens. pathogenic organisms were recovered from 277 (68.9%) patients and 97 (24.1%) controls. in the patient group, possible bacterial pathogens were found in 210 (52.2%) cases. enteropathogenic escherichia coli (epec) was the most frequently found potential pathogen, being recovered in 132 cases (32.8%) with serotypes 026, 086, 0111 and 0124 bei ... | 1990 | 2103408 |
| detection of entamoeba histolytica immunoglobulins g and m to plasma membrane antigen by enzyme-linked immunosorbent assay. | sixty-one serum specimens from 22 patients with clinically diagnosed amoebic liver abscess (ala), 10 hospitalized patients with a variety of diseases other than amoebiasis, 12 normal healthy controls, and 17 subjects from an amoebiasis-endemic area were assayed by enzyme-linked immunosorbent assay (elisa). the plasma membrane fraction of axenic cultures of entamoeba histolytica hk9 separated from other subcellular fractions by differential centrifugation was used as the antigen to detect specifi ... | 1990 | 2107203 |
| travelers' diarrhea among u.s. navy and marine corps personnel during a western pacific deployment. | the incidence and etiology of travelers' diarrhea was studied in a crew of 1,914 sailors and marines aboard a u.s. navy ship during a western pacific deployment. questionnaires completed by 301 troops indicated that 52% had at least one episode of diarrhea during the deployment; however, only 5% of the ship's company sought treatment. enterotoxigenic escherichia coli was the most commonly identified pathogen (23%), followed by giardia lamblia (6%), salmonella (3%), rotavirus (2%), and shigella, ... | 1990 | 2107464 |
| suppression of t-lymphocyte responses to entamoeba histolytica antigen by immune sera. | lymphocytes from patients cured of amebic liver abscesses proliferate and produce gamma interferon upon incubation with soluble entamoeba histolytica antigen: however, amebic liver abscesses exhibit a relentless progression without treatment. to determine whether suppressive factors are present in sera, we studied t-lymphocyte responses to total soluble e. histolytica antigen by using cells from five patients treated for amebic liver abscesses in the presence of 15 different immune sera and 10 c ... | 1990 | 2123828 |
| kupffer cell functions during intestinal amoebiasis in guinea pigs. | kupffer cells play an important role in all alimentary tract infections. their role in intestinal amoebiasis is not clear. hence, the present study examined kupffer cell functions--phagocytic capacity and levels of a key lysosomal enzyme, n-acetyl-beta-glucosaminidase -- in guinea pigs infected with entamoeba histolytica intracaecally. animals were sacrificed on days 0, 3, 7, 14 and 21 post-infection. during intestinal amoebiasis the phagocytic capacity in kupffer cells was depressed, whereas ly ... | 1990 | 2129823 |
| amoebicidal effect of essential oils in vitro. | the toxic effect of 84 essential oils was tested at different concentrations on entamoeba histolytica. 15 of them were the most efficient. 5 of the latter were detailed to give the percentages of their components. some families of plants have shown an homogeneity in the toxicity of their essential oils, while others, to the contrary, have presented heterogeneous amoebicidal activities. further investigations should be made to identify amoebicidal effects of essential oils in vivo. | 1990 | 2130180 |
| effects of berberine, a plant alkaloid, on the growth of anaerobic protozoa in axenic culture. | extracts obtained by organic solvents from the root of coptis teeta in myanmar (burma), were tested for growth inhibitory activity against giardia lamblia, trichomonas vaginalis and entamoeba histolytica in axenic culture. all extracts had anti-protozoal activity with the methanol extract, in particular, being effective against all 3 parasites. by chromatographic analysis, the extracts were shown to contain berberine compounds and other alkaloids. comparing the inhibitory effects of the methanol ... | 1990 | 2131648 |
| [growth inhibition of entamoeba histolytica and e. invadens produced by pomegranate root (punica granatum l.)]. | the purpose of the present work has been to evaluate the biological activity of alkaloids and tannins extracted from roots of punica granatum l. on axenic cultures from entamoeba histolytica and e. invadens, strains. initially, the total aqueous extract and later some of its components obtained by thin layer chromatography were tested. these compounds were identified by chromatography as alkaloids or tannins. the density of amebic cultures was determined with a hemocytometer after 48 and 96 hour ... | 1990 | 2131771 |
| [determination of cytoplasmic glycogen in 4 strains of amoeba of the genus entamoeba]. | the purpose of this work was made to determine the cytoplasmic glycogen concentration in trophozoites from four different strains of entamoeba genus. we used ip-1 and pz from e. invadens; hm-2 and hk-9 from e. histolytica strains, axenically cultured in tp-s-1 medium. the growth of different strains was determined each 24 hours during 10-days, with the aid of a hemocytometer. the quantification of cytoplasmic glycogen was made by two methods: 1) montgomery and 2) krisman. the glycogen concentrat ... | 1990 | 2131772 |
| [development of a simplified method for the axenic culture of entamoeba histolytica]. | since the tps-1 medium description, by diamond, for axenic cultivation of entamoeba histolytica trophozoites, a spectacular advance in this parasite biology knowledge has been occurred. recently we described a new medium, called pehps, which is as reliable as those of current use, and besides offers a more stable final density. from this latter, we developed, a new simpler medium, after being evaluated the specific contribution of several components of pehps. yields as high as those obtained wit ... | 1990 | 2131773 |
| [virulence factors of entamoeba histolytica]. | a panoramic view of the amebiasis concept, its pathogenesis and its epidemiologic importance is presented. besides, a brief description of the characteristic lesions of the mainly affected organs is done. then it is proposed a sequential relationship must occur in the amebic lesion production. finally, the best characterized amoebal infective factors are analyzed. this paper does not pretend to be an exhaustive review, but to offer an image of the pathogenetic mechanisms of amebiasis. | 1990 | 2131774 |
| experimental hepatic amoebiasis in inbred mice. | a model of hepatic amoebiasis in two inbred strains of mouse (swiss and balb/c, has been developed by introducing entamoeba histolytica-infected hamster liver tissue in between the adjacent liver lobes of mouse. it is expected that this model might be useful in studying various parameters of host-parasitic interactions and experimental chemotherapy of amoebiasis with relative ease. | 1990 | 2132506 |
| [host-parasite interactions: mechanisms for recognition and attack]. | host-parasite interactions were studied by several researchers in these last years, both to better understand some parasite diseases and to identify new targets and strategies for the control of these infections. in this paper some of the most important recognition's mechanisms demonstrated between specific parasite structures and host cell receptors are reported, and particularly those concerning protozoa leishmania, plasmodium, entamoeba, giardia and pneumocystis. | 1990 | 2133333 |
| overview of entamoeba histolytica and amebiasis in korea with special reference to research notes. | amebiasis caused by entamoeba histolytica infection has been a prevalent protozoan disease in korea since old times. for this reason, a number of scientific publications in relation to this protozoa has totaled 186 so far in the literature, as of 1989. the subjects ranged from biology to its treatment and prevention. the overall achievement by scientists and clinicians in korea has been meritorious in elucidating some of the pending problems in the areas of pathogenesis, diagnosis, and treatment ... | 1990 | 2133418 |
| [seroepidemiologic study of amebiasis in a community of the state of zulia, venezuela]. | in the present evaluation, a community of low socioeconomical conditions from zulia state, venezuela, was analyzed for the prevalence of antibodies to e. histolytica. two hundred and eighty three serum samples were collected and examined by the indirect hemagglutination test according to a microtiter modification of the kessel and lewis method, as used by milgram et al. antigen prepared from axenically-grown. e. histolytica strain hk9 in diamond's medium was used. the seropositivity rate obtaine ... | 1990 | 2135495 |
| [multidrug resistance in entamoeba histolytica]. | | 1990 | 2136471 |
| immunoreactivities for entamoeba histolytica in patients with amebic liver abscesses. | we defined the major specificities of antibodies present in sera from patients with amebic liver abscesses, diagnosed by gamagrafia. these immune reactivities were analyzed against plasma membrane and extract antigens of entamoeba histolytica, resolved by electrophoresis and blotted to nitrocellulose scheets. we observed that each of the 26 patients revealed a distinct pattern in the plasma membrane and in the total extract preparations. most of these sera detected a prominent plasma membrane po ... | 1990 | 2136472 |
| [trans-membrane potential in entamoeba]. | the membrane potential in entamoeba is an important driving force for the uptake of substrates. in entamoeba invadens pz a membrane potential of -36 mv was obtained when nernst equation was applied to the distribution at equilibrium of 86rb+ in the presence of valinomycin. this could explain the levels of accumulation of up to 4 times found for positively charged substrates. membrane potential was diminished by depolarizing conditions (high external k+ concentration in the presence of valinomyci ... | 1990 | 2136474 |
| [microcultures of entamoeba]. | the purpose of this study was the development of a microculture system for entamoeba using ultrathin culture chambers, characterized by constant culture conditions, where the growing amebas can constantly be observed under the microscope, and which allows rapid variations in the characteristics of the culture medium, so as to determine the optimal conditions for growth and encystment of the ameba. after a lag phase the number of amebas increased following exponential kinetics. the e. invadens di ... | 1990 | 2136475 |
| [direct relation between secretion of proteolytic enzymes and virulence in entamoeba histolytica]. | | 1990 | 2136478 |
| pathogenic and non-pathogenic zymodemes of entamoeba histolytica in a rural area of mexico. concordance with serology. | a) to describe the frequency of pathogenic and nonpathogenic zymodemes of e. histolytica in asymptomatic carriers in rural mexico, b) to identify the isoenzymatic pattern of the zymodemes and c) to measure the concordance of pathogenic zymodemes and positive serology. | 1990 | 2136479 |
| entamoeba histolytica: naturally occurring infections in baboons. | entamoeba chattoni frequently occurs as an intestinal infection in non-human primates. it has been isolated from both wild and captive animals. morphologically this amoeba resembles e. histolytica. e. histolytica has also been isolated from non-human primates on a number of occasions but these isolations have been from captive animals. in recent years identification of e. histolytica has been enhanced by the introduction of iso-enzyme electrophoresis methods. this technology has been widely appl ... | 1990 | 2136480 |
| [the mechanism of natural resistance in the rat to entamoeba histolytica]. | the data presented in this paper may be summarized as follows: 1) intraportal injection of a virulent strain (hm-1) of entamoeba histolytica in wistar rats, of both sexes, gives way to non-progressive microscopic changes, characterized by a rapid leukocytic reaction surrounding the amebas, disappearance of the parasites within 5 hours, and total lack of hepatic damage; 2) leucopenia only modifies the previous description by the fact that there are no leucocytes around the amebas, although these ... | 1990 | 2136481 |
| [seroepidemiology of amebiasis in the northern region of the republic of mexico]. | the object of paper has been the study of amebic seroepidemiology in the northern region of mexico, by means of an immunoenzymatic assay in solid phase (elisa). the proteic antigen was obtained from axenic culture of e. histolytica's trophozoites of strain hm1:imss, by means of solubilization with phenoxy polyethoxyethanol (triton x-100). standardization of the method was obtained by analysis of 80 sera from patients with both a clinical and radiologic diagnosis of amebic hepatic abscess and 80 ... | 1990 | 2136482 |
| [immunochemical differences in the surface polysaccharides obtained from entamoeba histolytica strain hm1:imss and its virulent (c-a) and non-virulent (l-6) clones]. | there probably exist many different surface molecular polysaccharides with different compositions of their constituent sugars, in the different zymodemes. this fact might have a repercussion upon the resistance to the lysis of the complement. seeking to prove this hypothesis, the ideal would be to obtain polysaccharide molecules of type lpfg of pathogenic and non-pathogenic zymodemes, demonstrating that there is a difference in the chemical composition of their polysaccharides. if this were true ... | 1990 | 2136483 |
| [proteins associated with actin: profilin in the trophozoites of entamoeba histolytica]. | the presence and distribution of profilin, an actin binding protein that regulates the actin organization, in trophozoites of entamoeba histolytica, strain hm1-imss was examined using polyclonal antibodies against calf spleen profilin. the results shows: (1) in entamoeba extracts a peptide that comigrates with spleen profilin and representing 0.86% of the total cells proteins, (2), this peptide is immunoprecipitated by antibodies antiprofilin, and (3) stained cells with the antibodies shows the ... | 1990 | 2136484 |
| [characterization of entamoeba histolytica proteins which participate in the interaction with target cells of different species]. | | 1990 | 2136485 |
| efficacy of zymodemes of e. histolytica technique in an epidemiologic study and report of new zymodemes in mexico. | to determine the efficacy of zymodemes of e. histolytica technique in an epidemiologic study. to report the zymodemes for the first time described in mexico. to report the main difficulties in the correct classification of zymodemes in this study. to describe the zymodemes identified in two evaluations done in 100 healthy individuals. | 1990 | 2136486 |
| study of human entamoeba histolytica infection by zymodeme, indirect hemagglutination and electroimmunotransfer blot assays. | human amebiasis is a parasitic infection which involves asymptomatic as well as intestinal and extraintestinal symptomatic stages in individuals harbouring entamoeba histolytica. several factors have been proposed to explain the variability in the outcome of the disease. among these are differences in virulence of e. histolytica strains and methods such as zymodeme analysis have been used to differentiate invasive from non invasive strains of this parasite (sargeaunt and williams, 1978). in orde ... | 1990 | 2136487 |
| [molecular differences between pathogenic and nonpathogenic amoebae of entamoeba histolytica]. | | 1990 | 2136488 |
| [identification of entamoeba histolytica chromosomes by pulsed field gradient electrophoresis]. | the use of pulsed field gradient electrophoresis (pfg) has simplified the study of chromosomic organization in protozoan parasites whose chromosomes do not condense during division. in this paper we used pcg to analyzed chromosome organization entamoeba histolytica's. in the conditions which we used (200 volts, 24 hours, 3 minute pulses and the anode at 7.5 cm. from the end of the cathode) 6 and 9 band of amebic dna were resolved. by means of a ribosomal dna probe from trypanosoma brucei amebic ... | 1990 | 2136489 |
| [in vitro sensitivity of entamoeba histolytica to metronidazole]. | the chemotherapy of amebiasis includes different substances with intra and extraintestinal action. nowadays, metronidazole is the election drug by its high efficacy and low toxicity. some therapeutic failures with metronidazole in patients with invader amebiasis and some reports of resistance to it, of certain strains of trichomonas vaginalis and species of bacteroides have caused an increased interest to do new in vitro evaluation of this compound and to search of new antiamebic drugs. the obje ... | 1990 | 2136490 |
| [fecal and serum anti-amebic antibodies in acute intestinal amebiasis]. | antiamebic antibody titers, were investigated in the feces and sera of 30 adults patients with intestinal amoebiasis, during the first two weeks of disease. also, 29 control samples of healthy adult subjects were studied. the objective of this study was to determine if the local or systemic igg, igm or iga levels were modified during the early stages of acute intestinal amoebiasis, for this purpose elisa technique was use. anti e. histolytica antibody titers in fecal samples of patients were not ... | 1990 | 2136492 |
| [axenic and polyxenic antigens of entamoeba histolytica in the diagnosis of human amebiasis]. | a comparison of the antigenic activity of soluble extracts of entamoeba histolytica kept in axenic and polyxenic cultures is undertaken. special care was kept so as to keep the protein native structure unharmed. chromatographic separation at g-200 was performed, and three fractions were obtained and submitted to reactions with the sera of 10 patients with a proven diagnosis of amebic hepatic abscess, 5 patients with amebic dysentery from whom the protozoon was isolated and cultured from feces, a ... | 1990 | 2136493 |
| [entamoeba histolytica proteins which participate in the adhesion to human erythrocytes]. | | 1990 | 2136494 |
| [identification and localization of molecules which intervene in the interaction between entamoeba histolytica and epithelial cells]. | during the initial stages of host-parasite interaction between entamoeba histolytica and its target cell, superficial molecules of both cells participate. the purpose of this study has been the study of the parasite's proteins which are involved in the process of adhesion, as well as localize the superficial sites of the host which bind with the amebic proteins. antibodies directed against adhesin 112 kda, and other amebic adhesins, specifically inhibited the destruction of the monolayers of the ... | 1990 | 2136495 |
| an entamoeba histolytica antigen devoid of enzymatic activity, but endowed with immunogenic and protective properties. | one of the most relevant features of entamoeba histolytica extracts is their great enzymatic activity. the consequence of this peculiarity is that these extracts digest not only extrinsic proteins but also those within the parasite, causing instability during extract preparation which makes their characterization more difficult and hinders their use in immunoprophylaxis. this report presents evidence which indicates that treatment of e. histolytica extracts with a ph2 acid shock for 30 min at 37 ... | 1990 | 2136496 |
| [localization of entamoeba histolytica antigens using iga]. | the presence of iga anti-entamoeba histolytica antibodies has been demonstrates in intestinal secretions and serum of human amebiasis. we investigated which are the cellular components of trophozoites that react with iga anti-ameba antibodies from immune serum, colostrum and human milk. the cellular localization of such antigens was accomplished by an indirect immunoperoxidase technique using anti-human iga (alpha chain specific) labeled with peroxidase, both for light and transmission electron ... | 1990 | 2136497 |
| evaluation of an immunoblot methodology for the detection of relevant entamoeba histolytica antigens by antibodies induced in human amebiasis. | the complexity of the clinical spectrum in human amebiasis and the high variability in laboratory methods used to detect entamoeba histolytica infections have impeded the collection and evaluation of reliable epidemiological data. thus, more sensitive, specific and standardized methods are needed in order to accurately identify infections with this parasite. an important step in the development of serological diagnostic methods is the identification and isolation of specific parasite antigens wh ... | 1990 | 2136499 |
| [presence of proteins and genes homologous to the c-myc proto-oncogene in entamoeba]. | | 1990 | 2136500 |
| detection of igg, iga, igm and ige in antibodies in invasive amoebiasis in endemic areas. | entamoeba histolytica--specific serum igg, iga, igm and ige were assayed in cases of amoebiasis in an endemic area. patient groups consisted of amoebic liver abscess (n = 18), pre abscess hepatic amoebiasis (n = 22) and amoebic colitis (n = 30). control subjects comprised 26 asymptomatic cyst passers, 13 giardiasis cases, 20 typhoid patients and 24 non amoebic individuals. serum igg was assayed by elisa: using a monoclonal anti igg beta-galactosidase (igg beta-gal) conjugate, a polyclonal avidin ... | 1990 | 2136501 |
| [experimental intestinal amebiasis: invasion and extension of the amebic lesion]. | a morphological analysis of an experimental model of invasive intestinal amebiasis was carried out using the washed-closed cecal loop model in hamsters and guinea-pigs. by light microscopy, few amebic trophozoites adhered to the intestinal epithelium, whereas many associated to the mucus blanket. some trophozoites attached to the interglandular epithelium, during the first 10 to 15 hours of interaction. hereafter, the parasites destroyed gradually the epithelium and were associated with normal a ... | 1990 | 2136502 |
| early expression in mice of genetic resistance to intestinal amebiasis. | some strains of mice are known to be relatively resistant to hepatic or intestinal amebic infections. in order to know if the intestinal resistance is expressed few hours after infection, we inoculated axenic amebae in three inbred strains of mice either by direct intracecal injection or by infection of a washed-closed cecal loop. we found that amebae do not survive in conventional animals but they colonize longer in animals with the cecal loop. however, the survival was low after 24 hours posti ... | 1990 | 2136503 |
| entamoeba histolytica inhibits the respiratory burst of polymorphonuclear leukocytes. | since toxic oxygen metabolites generated during the respiratory burst of polymorphonuclear neutrophils (pmns) constitute one of the most potent microbicidal mechanisms of pmns, we evaluated the in vitro capacity of e histolytica to trigger the respiratory burst of human pmns using a luminol-enhanced chemiluminescence assay a highly virulent strain of e. histolytica (hm1-imss) and a less virulent one (hk9-nih) were incubated with pmns at 4:1, 2:1 and 1:1 pmn:amoebae ratios. we have observed that ... | 1990 | 2136504 |
| antibodies against entamoeba histolytica antigens in sera from individuals with amoebiasis of different localization. | the over-all contents and relative component composition of entamoeba histolytica antigens in abscess fluids and in extracts of cultured amoebae, strain nih 200, were studied by antigen-catching eia, counterimmunoelectrophoresis (cie) and immunoblotting techniques. the antigen contents of liver abscess fluid were determined semiquantitatively by the antigen-catching eia in four cases. in cie against a standard "diagnostic" extract of cultured amoebae, sera from cases of acute amoebic liver absce ... | 1990 | 2136505 |
| mitosis and polykaryon formation of entamoeba histolytica in axenic cultures. | axenic cultures of e. histolytica were established in coplin jars containing glass slides. the cultures were harvested after 72 hours, fixed and stained with giemsa and acridine orange. sedimented parasites were used for inclusion in methacrylate for thin sections that were stained with acridine orange, and epon-araldite for ultrathin sections for electron microscope study. the giemsa stain showed trophozoites of different sizes and variation in the shape, size and number of the nuclei. division ... | 1990 | 2136506 |
| [subcellular localization and biochemical characterization of the 112-kd adhesin in entamoeba histolytica]. | | 1990 | 2136507 |
| [role of macrophages and t-lymphocytes: resistance of guinea pigs to amebic liver infection]. | the mechanisms of host resistance in hepatic amebiasis are poorly understood. previous studies in guinea-pigs have shown that amebic liver infection is mild and cures spontaneously in approximately four days, in contrast to hamsters, where amebic liver infection progresses to coalescent abscesses that kill the animals in about one month. to determine the role of macrophages in the resistance of guinea-pigs to hepatic amebic infection, animals were treated with intraportal injection of entamoeba ... | 1990 | 2136508 |
| identification of entamoeba histolytica antigens recognized by iga class human antibodies in sera and colostra of puerperal women using immunoblotting techniques. | immunodetection of total antigens of entamoeba histolytica trophozoites transferred to nitrocellulose paper was realized with iga antibodies present in colostra and sera samples of 28 puerperal women and in 24 sera samples of patients with a diagnosis of amebic hepatic abscess. the most frequently recognized antigens by colostra antibodies were those which correspond to 1290, 82.79, 52.14, 40.91, 37.75, 35.08, 33.52, 28.53, 27.53 and 25.32 kda of molecular weight, in the case of puerperal sera t ... | 1990 | 2136509 |
| entamoeba histolytica--the virulence of imported strains. | we tested the virulence of 15 strains of entamoeba histolytica, imported to czechoslovakia, by intracaecal inoculation of laboratory rats. according to the scoring system of neal, none of the 15 strains possessed the virulence index greater than 2. this indicates that all the organisms tested should be classified as avirulent. however, it should be noted that all the strains produced infection of the caecum and thus should be considered infective for rat. for 7 strains, isoenzyme patterns were d ... | 1990 | 2139631 |
| zymodeme conversion of isolates of entamoeba histolytica. | a non-cloned and a cloned isolate of non-pathogenic (zymodeme i) entamoeba histolytica derived from homosexual males were incubated in diamonds' tp-s-1 medium in the presence of crithidia for 52 d. a single addition of escherichia coli irradiated at 1000 gy rendered the culture axenic. analysis of zymodeme patterns established that both isolates had transformed to zymodeme ii. the re-establishment of cultures in the presence of microflora from the original cultures resulted in a return to zymode ... | 1990 | 2140626 |
| evidence for a vacuolar-type proton atpase in entamoeba histolytica. | entamoeba histolytica is a primitive eukaryote that lacks mitochondria. golgi and a well-developed endoplasmic reticulum. close to half of the cell volume is occupied by pinocytic vesicles, which are in continuous turnover with the plasma membrane and perform functions that in higher eukaryotic cells are taken over by lysosomes. similar to the latter, the amebal vesicles are acidified. we report here that bafilomycin a1, a specific inhibitor of vacuolar-type (v-) atpases, suppressed this acidifi ... | 1990 | 2141984 |
| [current questions in parasitology and infection prevention]. | topical treatment of cutaneous larva migrans with thiabendazole and cambendazole is briefly described. aids has focused attention on the coccidial parasites cryptosporidium spp. and isospora belli because they can be responsible for severe chronic enteritis in immunodeficient patients. the species formerly known as isospora hominis--after detection of its life cycle--has now been correctly named sarcocystis bovihominis and s. suihominis, respectively. in future, patients harbouring commensal str ... | 1990 | 2146554 |