Publications

frequency of intestinal parasites in adult cancer patients in mexico.	approximately 28% of the mexican population has intestinal parasites. oncologic patients receiving chemotherapy should have a coproparasitoscopic study to avoid disseminated parasitic infections. the frequency of intestinal parasites, including cryptosporidium and isospora, was evaluated in 100 diarrheic (ds) and 100 formed stools (fs) from adult patients recently diagnosed with cancer, using wet mounts stained with kinyoun, saccharose and znso4 procedures stained with lugol's iodine. seven pati ...	1997	9204612
[amebic colitis and amebic liver abscess--epidemiology and personal case report].	the large intestine reacts relatively monomorphically to different stimuli. from this differential-diagnostic problems may result. the history of a patient is described which could be pursued clinically over 12 weeks and during the course of which the correction of the diagnosis ulcerative colitis into amoebic colitis was necessary. it is concluded that in every symptomatology of colitis bacterial and parasitologic examinations of the faeces should be performed primarily specially if there is a ...	1997	9206916
prevalence of intestinal parasites in the human population of león, nicaragua.	intestinal parasites appear to be prevalent in nicaragua, which motivated a more extensive prevalence study in which socioeconomic conditions such as degree of crowding, quality of water supply, type of floor and disposal of excretion, were considered. the study was performed on 1267 stool samples from about 8% of the citizens of the city of león. the overall prevalence of intestinal pathogenic parasites among the 1267 individuals was found to be 47.2%. the prevalence of entamoeba histolytica/di ...	1997	9210962
molecular medicine's applications to the developing world: enlightened self interest.		1997	9211411
preparation of a monoclonal antibody specific for entamoeba dispar and its ability to distinguish e. dispar from e. histolytica.	a monoclonal antibody (mab), mab ed17 (immunoglobulin g2a [igg2a]), prepared against trophozoites of entamoeba dispar saw1734rclar cultured monoxenically with crithidia fasciculata, reacted with 25 of 26 isolates of e. dispar by an indirect fluorescent-antibody test. in contrast, the mab failed to react with any of 20 isolates of e. histolytica or other enteric protozoan parasites. western blot (immunoblot) analysis showed that the molecular mass of the e. dispar antigen recognized by the mab wa ...	1997	9220156
human intestinal epithelial cells produce proinflammatory cytokines in response to infection in a scid mouse-human intestinal xenograft model of amebiasis.	the protozoan parasite entamoeba histolytica causes amebic dysentery and amebic liver abscess, diseases associated with significant morbidity and mortality worldwide. e. histolytica infection appears to involve the initial attachment of amebic trophozoites to intestinal epithelial cells, followed by lysis of these cells and subsequent invasion into the submucosa. a recent in vitro study (l. eckmann, s. l. reed, j. r. smith, and m. f. kagnoff, j. clin. invest. 96:1269-1279, 1995) demonstrated tha ...	1997	9125540
interleukin (il)-2, il-4, and tumor necrosis factor-alpha responses during entamoeba histolytica liver abscess development in gerbils.	to determine cytokine production patterns during hepatic amebiasis, gerbils were infected with entamoeba histolytica in the liver. then spleen and hepatic lymph node cell proliferation and interleukin (il)-2 (a th1 marker), il-4 (a th2 marker), and tumor necrosis factor-alpha (tnf-alpha) production in response to concanavalin a and amebic antigen in vitro were quantified. early abscess development (day 5 after inoculation) coincided with il-2, il-4, and low tnf-alpha production and strong lympho ...	1997	9129082
characterization of nucleoside uptake and transport in entamoeba histolytica.	the uptake and transportation of purine and pyrimidine based nucleosides by trophozoites of axenically grown entamoeba histolytica (hmi-imss) were studied. the trophozoites transported adenosine and its analog tubercidin (1 microm) at a significant rate but poor transportation was observed in case of uridine (about 10% relative rate), inosine (3%), thymidine (2%) and formycin b (1%). the km for adenosine was 160 +/- 42 microm. unlabeled nucleosides (100 microm) inhibited adenosine and tubercidin ...	1997	9134559
in vitro entamoeba histolytica adhesion to human endothelium: a comparison using two strains of different virulence.	extraintestinal dissemination of entamoeba histolytica is frequently manifested by the life-threatening amebic liver abscess (ala). the hepatic establishment of amebas implies invasion of blood vessels and contact with the endothelium. by means of a fluorescence-based quantitative adhesion assay, we assessed the binding to human endothelial cells of two e. histolytica strains of different virulence. the highly virulent strain (l-a) adhered substantially more strongly to unstimulated endothelium ...	1997	9134567
entamoeba histolytica stimulates interleukin 8 from human colonic epithelial cells without parasite-enterocyte contact.	the mechanisms involved in the initiation of host mucosal inflammation in amebiasis are not fully understood. this study characterized the effect of entamoeba histolytica components on interleukin 8 (il-8) gene expression in human colonic cells.	1997	9136832
a mechanism of acquired resistance to complement-mediated lysis by entamoeba histolytica.	some entamoeba histolytica strains resist complement-mediated lysis by serum. susceptible and resistant strains activate the complement system equivalently, but resistant amebas evade killing by membrane attack complexes. our objective was to determine the mechanism by which trophozoites of e. histolytica resist lysis by human serum. amebas were made resistant to lysis by incubation with increasing concentrations of normal human serum. the possibility that resistant cells ingest membrane attack ...	1997	9105303
cloning and expression of chitinases of entamoebae.	entamoeba histolytica (eh) and entamoeba dispar (ed) are protozoan parasites that infect hundreds of millions of persons. in the colonic lumen, amebae form chitin-walled cysts, the infectious stage of the parasite. entamoeba invadens (ei), which infects reptiles and is a model for amebic encystation, produces chitin synthase and chitinase during encystation. ei cysts formation is blocked by the chitinase-inhibitor allosamidin. here molecular cloning techniques were used to identify homologous ge ...	1997	9106188
electron probe analysis and biochemical characterization of electron-dense granules secreted by entamoeba histolytica.	the interaction of entamoeba histolytica with collagen induces the intracellular formation and release of electron-dense granules (edgs) containing collagenase activity which are important in the pathogenicity of this parasite. purified edgs contain at least 25 polypeptides with acidic pis, nine gelatinase activities, small molecules, including inorganic phosphate (pi), pyrophosphate (pp) and other elements, including na, mg, s, cl, k, ca and fe as measured by scanning transmission electron micr ...	1997	9106196
an improved colorimetric pcr-based method for detection and differentiation of entamoeba histolytica and entamoeba dispar in feces.	the epidemiological implications of the recent separation of "entamoeba histolytica" into two separate species, pathogenic e. histolytica sensu stricto and commensal e. dispar, will not become apparent without methods of distinguishing between them which are applicable to large numbers of specimens. we have modified a pcr-based method to produce such a technique which may be completed in 1 day while still identifying 10(-1) e. histolytica and 1 to 10 e. dispar trophozoites per g of feces when pr ...	1997	9114390
antimicrobial peptides of leukocytes.	leukocytes use an array of antimicrobial peptides and proteins to help them destroy invading microorganisms. these endogenous antibiotic molecules are remarkable for their structural variety, rapid evolutionary divergence, intraspecies variation, and complex yet subtle interactions with their targets. this arsenal has been studied most extensively in neutrophils, where its members include lactoferrin, secretory phospholipase a2, lysozyme, and the cathelicidins in the secretory granule compartmen ...	1997	9050380
virulent and avirulent entamoeba histolytica and e. dispar differ in their cell surface phosphorylated glycolipids.	virulent strains of entamoeba histolytica have been reported to produce a mixture of phosphoglycoconjugates that share some structural features with the lipophosphoglycans (lpgs) of leishmania. purification of these glycoconjugates is essential to their precise structural characterization. in this study we have extracted 'lpg-like' molecules from various virulent e. histolytica strains and purified on the basis of charge differences, 2 apparently related glycoconjugates a 'lpg' and a 'lipophosph ...	1997	9051918
intragastric immunization of rats with entamoeba histolytica trophozoites induces cecal mucosal ige, eosinophilic infiltration, and type i hypersensitivity.	we have investigated the role of ige in the local immunity of intestinal amebiasis, a parasitic infection known to induce specific antibody-forming cells (afc) and iga antibodies in rodents and humans. we found that intragastric immunization of rats with glutaraldehyde-fixed entamoeba histolytica trophozoites significantly increased antiameba afc in the peyer's patches and spleen and that the lamina propria of the cecum from immunized animals was infiltrated by eosinophils armed with ige antibod ...	1997	9073545
cytoplasmic dna in entamoeba histolytica: its biological significance.	we report a study on the dna organization in entamoeba histolytica using a ribosomal dna probe. the rdna genes were found forming mers which were separated in a typical ladder pattern by pulse field electrophoresis. dna rosette structures were visualized through electron microscopy in dna eluted from bands recognized by the ribosomal probe. the in situ hybridization experiments using a dna probe suggested that the rdna genes are portioned between the nucleus and a cytoplasmic structure. these fi ...	1997	9078580
acute diarrhea in under five-year-old children admitted to king mongkut prachomklao hospital, phetchaburi province.	a prospective epidemiological and clinical study of acute diarrhea in children under 5 years old was done at king mongkut prachomklao hospital in order to provide baseline data for health officers to make a strategic plan to reduce the diarrheal mortality and morbidity, which is one of the mid-decade goals for children. there were 105 cases of acute diarrhea patients admitted to the pediatric ward between may 1995 and april 1996. seventy-six per cent of them were in the younger age group (> 1 mo ...	1997	9078814
molecular modeling of amoebapore and nk-lysin: a four-alpha-helix bundle motif of cytolytic peptides from distantly related organisms.	amoebapore of the protozoan entamoeba histolytica and nk-lysin of porcine cytotoxic lymphocytes are effector peptides from organisms separated extremely early in their evolutionary paths. the peptides intrigued us, however, with indications of some functional similarity. we thus wanted to derive and compare predictions for their as yet unknown three-dimensional structures as a guide for and to be tested by further experiments.	1997	9080198
molecular characterization of the entamoeba histolytica enolase gene and modelling of the predicted protein.	entamoeba histolytica obtains its energy mainly from glucose fermentation. enzymes involved in this pathway could be potential targets for antiparasite drugs. here we report the molecular characterization of the e. histolytica enolase gene (ehenl-i), which in a single copy is located on the 1.6 mb chromosome. it is transcribed into a 1.4 kb mrna which starts 13 nucleotides upstream of the atg start codon. the sequence tataag, at -31, interacted with nuclear proteins suggesting that it has a tata ...	1997	9084139
the root hair defective3 gene encodes an evolutionarily conserved protein with gtp-binding motifs and is required for regulated cell enlargement in arabidopsis.	in plants, morphogenesis is largely determined by the orientation and extent of cell enlargement. to define the molecular mechanisms regulating plant cell enlargement, we have conducted a molecular genetic analysis of the root hair defective3 (rhd3) gene of arabidopsis thaliana. mutations affecting the rhd3 gene were found to alter cell size, but not cell number, in tissues throughout the plant. genetic and physiological analyses suggest that the rhd3 gene is not required for proper cell type sp ...	1997	9087433
entamoeba histolytica and entamoeba dispar infection in children in bangladesh.	the prevalence of infection by the invasive parasite entamoeba histolytica and the noninvasive parasite entamoeba dispar was determined in 2000 children in bangladesh. antigen detection identified more cases of e. histolytica-e. dispar infection than did culture or microscopy. microscopic identification of e. histolytica-e. dispar complex infection in stool did not equate with the diagnosis of amebic dysentery because most amebic infections in this population were due to e. dispar: urban childre ...	1997	9041357
characterization of ehcabp, a calcium-binding protein of entamoeba histolytica and its binding proteins.	a novel calcium-binding protein (ehcabp) has been recently identified and characterized from the protozoan parasite entamoeba histolytica. in order to decipher the function of this protein, a few basic properties were investigated and compared with the ubiquitous ca(2+)-signal transducing protein calmodulin (cam). indirect immunofluorescence and immunoprecipitation analyses using specific antibodies against ehcabp suggest that it is a soluble cytoplasmic protein with no major post-translational ...	1997	9041522
tetracycline-controlled gene expression in entamoeba histolytica.	to provide further tools for functional genetics of the protozoan parasite entamoeba histolytica, we have tested the suitability of the bacterial tn10-encoded tet-repressor/tet-operator system for gene regulation in ameba trophozoites. expression of the tet-repressor within the ameba was driven by the wild-type endogenous lectin gene promoter from episomal transfected plasmids. tetracycline-inducible expression of a reporter gene driven by a modified tet-operator-bearing lectin gene promotor was ...	1997	9041523
a tetracycline-inducible gene expression system in entamoeba histolytica.	we have developed an episomal inducible gene expression system in entamoeba histolytica based on the tetr repressor. the tetr gene was placed under control of 5' and 3' ferredoxin (fdx) regulatory sequences on a plasmid encoding the hygromycin resistance gene directed by 5' and 3' hgl sequences. the reporter luciferase constructs were introduced on a second episome bearing the neomycin resistance gene controlled by 5' and 3' actin sequences. the reporter constructs were driven by the hgl5 promot ...	1997	9041524
the entamoeba histolytica proteasome alpha-subunit gene.		1997	9041528
protozoal agents: what are the dangers for the public water supply?	safe and efficient treatment of drinking water has been one of the major public health advances of the twentieth century. people in developed countries generally take for granted that their water is safe to drink, a luxury the majority of the world's population does not have. the leading cause of infant mortality in the developing world is infectious diarrhea, and the prevalence of diarrheal pathogens is largely influenced by the quality and quantity of clean water available for drinking and was ...	1997	9046966
does non-dysenteric intestinal amoebiasis exist?	chronic abdominal pain and frequent bowel disturbance are common symptoms experienced by more than 15% of apparently healthy people. in areas endemic for entamoeba histolytica infection, these symptoms are often diagnosed as non-dysenteric intestinal amoebiasis even though no causal relation between such symptoms and e histolytica has been established and clinical presentation of non-dysenteric intestinal amoebiasis and irritable bowel syndrome (ibs) is not distinct. this study was done to asses ...	1997	8996420
identification of entamoeba histolytica and e. dispar cysts in stool by polymerase chain reaction.	an attempt to identify cysts of entamoeba histolytica and e. dispar in human stool was conducted by polymerase chain reaction (pcr) using two sets of primers (p11 plus p12 and p13 plus p14) specific for either species of ameba. the cysts in stool specimens obtained from 12 infected individuals were concentrated, freeze-thawed, and treated with triton x-100 before their examination by pcr. the results of pcr on the cysts were generally consistent with data obtained by pcr on ameba trophozoites ha ...	1997	9000244
waterborne protozoan pathogens.	protozoan parasites were the most frequently identified etiologic agents in waterborne disease outbreak from 1991 to 1994. the waterborne parasites giardia lamblia, naegleria fowleri, acanthamoeba spp., entamoeba histolytica, cryptosporidium parvum, cyclospora cayetanesis, isospora belli, and the microsporidia are reviewed. for each parasite, the review includes history, life cycle, incidence, symptoms, and therapy. clinical detection methods are compared, and emerging technologies are discussed ...	1997	8993859
royal society of tropical medicine and hygiene meeting at manson house, london, 19 february 1998. amoebic disease. entamoeba histolytica and e. dispar: comparison of molecules considered important for host tissue destruction.	entamoeba histolytica and e. dispar are genetically distinct but closely related protozoan species. both colonize the human gut but only e. histolytica is able to invade tissues and cause disease. comparison of the 2 species may help to elucidate the specific mechanisms involved in the pathogenicity of e. histolytica. during the last few years, various amoeba molecules considered to be important for pathogenic tissue invasion have been identified and characterized, such as a galactose-inhibitabl ...	1998	10326098
the cloning and sequencing of ribosomal protein s18 of parasitic protozoa, entamoeba histolytica.	a cdna clone encoding ribosomal protein s18 has been isolated from parasitic protozoa, entamoeba histolytica. the cdna insert was 495 nucleotides long and an open reading frame (468 nucleotides including the stop codon) coded for 156 amino acid protein which was highly homologous with human, plant and yeast counterparts. prosite analysis of the ribosomal protein s18 in eukaryote revealed homology with prokaryotic ribosomal protein s13 signature, which is known to be involved in the initiation of ...	1998	10520458
crystallization and preliminary x-ray studies of a recombinant calcium-binding protein from entamoeba histolytica.	a calcium-binding protein (cabp) of entamoeba histolytica was purified from an e. coli recombinant clone carrying the cabp gene in a pet-3c expression vector using anion-exchange and size-exclusion chromatography. examination of the amino-acid sequence of the recombinant protein suggested that it has four independent ef-hand motifs. the protein dissolved in cacodylate buffer was crystallized using the hanging-drop method with 2-methylpentane-2,4-diol (mpd) as the precipitant. x-ray diffraction d ...	1998	10089533
[pleuropulmonary manifestations of amebiasis].	amibiasis is the third leading cause of death due to parasitic infections in the world. amibiasis is endemic in the warm regions of the world with deficient hygiene and socio-economic situations. entamoeba histolytica is the causal agent of invasive amibiasis, unlike entamoeba dispar which is not a pathogen for humans. amibian colitis and amibian abscess of the liver are the most frequent intestinal and extra-intestinal manifestations. pleuropulmonary complications almost always occur in patient ...	1998	10100347
trendys in biochemistry-98.		1998	10515725
application of the polymerase chain reaction (pcr) in the epidemiology of entamoeba histolytica and entamoeba dispar infections.	in this paper, we briefly summarize the latest information on the polymerase chain reaction (pcr) as an epidemiologic tool for entamoeba histolytica and entamoeba dispar infections. this method which employs dna template directly extracted from formalin fixed stool specimens offers a good promise for an accurate and reliable epidemiology of the two species. the assay is, sensitive enough to detect as few as five cysts in the stool sample, rapid and selectively differentiates e. histolytica from ...	1998	10622639
effects of aphidicolin on entamoeba histolytica growth and dna synthesis.	we have detected and characterized dna polymerase activity in cell extracts from trophozoites of entamoeba histolytica and have found that the activity of e. histolytica is inhibited by aphidicolin, which is a specific inhibitor of eukaryotic nuclear replicative dna polymerases. the present study was aimed to evaluate the effect of aphidicolin on growth and dna synthesis by this parasite. aphidicolin blocked the growth of axenic e. histolytica strain hm-1: imss. dna synthesis was also inhibited ...	1998	10622640
role of serum in regulating the entamoeba histolytica cell cycle: a flowcytometric analysis.	to identify stage-specific molecules that might be important in pathogenicity, we focused on synchronizing entamoeba histolytica hm1:1mss axenic cultures by serum deprivation. by growing trophozoites in medium containing 2% serum for 16 h and then replacing with complete medium, we found that most of the trophozoites were in the g0/g1 phase of the cell cycle. subsequently, the distribution of trophozoites in g0/g1, s and g2/m phases was studied for up to 24 h and it was observed that after 8 h, ...	1998	9797069
heat shock protein 70 family: multiple sequence comparisons, function, and evolution.	the heat shock protein 70 kda sequences (hsp70) are of great importance as molecular chaperones in protein folding and transport. they are abundant under conditions of cellular stress. they are highly conserved in all domains of life: archaea, eubacteria, eukaryotes, and organelles (mitochondria, chloroplasts). a multiple alignment of a large collection of these sequences was obtained employing our symmetric-iterative iteralign program (brocchieri and karlin 1998). assessments of conservation ar ...	1998	9797407
secretory immune response in patients with intestinal amoebiasis.	the secretory immune response in saliva from intestinal amoebiasis patients against antigens obtained from entamoeba histolytica membranes was studied. western blot analysis indicated that patient saliva contains secretory iga antibodies against antigens with molecular masses ranging from 170 to 24 kda, some of which were also recognized by saliva from healthy subjects. however, antigens of 170, 125, 46 and 37 kda are recognized more frequently (> 90%) by the secretory iga from patients with int ...	1998	9797512
molecular characterization of an exceptionally acidic lysozyme-like protein from the protozoon entamoeba histolytica.	the protozoan parasite entamoeba histolytica contains a second antibacterial protein with lysozyme-like properties. the newly recognized bacteriolytic protein was purified from extracts of amoebic trophozoites to allow amino-terminal sequencing. subsequent molecular cloning revealed that it is an isoform of the amoeba lysozyme described previously but also demonstrated a substantial sequence divergence of the two forms. as lysozymes typically are basic proteins, the novel amoebic protein differs ...	1998	9804191
entamoeba histolytica: identification of functional gs and gi proteins as possible signal transduction elements in the interaction of trophozoites with fibronectin.	trophozoites of entamoeba histolytica adhere to several components of the extracellular matrix. binding is mediated by specific receptors identified in the parasite surface. interaction of trophozoites with fn induces the formation of special adhesion structures that are dynamic cytoskeleton membrane complexes and facilitate both adhesion and substrate degradation. the process requires activation of signaling pathways in which plc, ip3, ca2-, and pkc participate. these observations, and recent e ...	1998	9806871
ribosomal dna fragments enhance the stability of transfected dna in entamoeba histolytica.	genetic manipulation of entamoeba histolytica is limited by the inability to express foreign genes at high levels. we tested whether sequences from the e. histolytica rdna episome, present in 200 copies per cell, could act to stabilize the episomal transfection vector ptcv1. ligation of the rdna transcription unit, or sequences downstream of the rdna transcription unit, increased ptcv1 copy number and stability and conferred additional zones of dna replication. sequences upstream of the rdna tra ...	1998	9864856
69-year-old man with fever, diarrhea, and abdominal pain.		1998	9868422
induction of a spectroscopically defined transition by guanidinium hydrochloride on a recombinant calcium binding protein from entamoeba histolytica.	sequence analysis and metal ion binding studies reported earlier have established that the calcium binding protein (cabp) from the parasitic ameboid entamoeba histolytica protein has four canonical ef hand motifs which bind calcium. equilibrium denaturation studies on both the apo and the holo forms of this protein indicate the presence of stable transition intermediates at low denaturant concentrations as revealed by the binding of the non-specific hydrophobic dye ans. fast reaction kinetics sh ...	1998	9877168
molecular cloning and characterization of the genes encoding two isoforms of cysteine synthase in the enteric protozoan parasite entamoeba histolytica.	the enteric protozoan parasite entamoeba histolytica was shown to possess cysteine synthase (cs) activity. the cdna and genomic clones that encode two isoforms of the e. histolytica cs were isolated and characterized from a clonal strain of e. histolytica by genetic complementation of the cysteine-auxotrophic escherichia coli nk3 with an e. histolytica cdna library. the two types of the e. histolytica cs genes differed from each other by three nucleotides, two of which resulted in amino acid sub ...	1998	9879885
field study on the distribution of entamoeba histolytica and entamoeba dispar in the northern philippines as detected by the polymerase chain reaction.	we used the polymerase chain reaction (pcr) to study the distribution of entamoeba histolytica and e. dispar in 1,872 individuals in 14 communities in the northern philippines. here we report a field study using a dna extraction protocol from formalin-fixed stool specimens as previously reported. this assay detected 137 stools (7.318%) containing e. dispar and 18 stools (0.961%) containing e. histolytica. the most affected age group for e. histolytica/e. dispar infections were those 5-14 years o ...	1998	9886200
etiologies of acute, persistent, and dysenteric diarrheas in adults in bangui, central african republic, in relation to human immunodeficiency virus serostatus.	a study of the etiologies of diarrhea in adults in relation to their human immunodeficiency virus (hiv) serostatus and number of cd4+ cells was carried out in the central african republic. in cases and controls, multi-parasitism was observed. salmonella spp. were identified mainly during acute diarrhea, with 50% of the s. enteritidis isolated during the study being responsible for septicemia and/or urinary tract infection in immunodeficient patients. enteroaggregative escherichia coli (eaggec) w ...	1998	9886215
inhibition of entamoeba histolytica proteolytic activity by human salivary iga antibodies.	entamoeba histolytica is a protozoan parasite that causes amoebiasis in humans; as the infection occurs mainly in the intestinal epithelium, the secretory immune response of the host could have an influence on the outcome. secretory iga antibodies against e. histolytica have been detected in asymptomatic and symptomatic patients, but little is known about their protective role. e. histolytica cysteine proteases seem to be involved in the pathogenesis of amoebiasis; therefore, it is important to ...	1998	9890272
giardia lamblia: in-vitro sensitivity to some chemotherapeutic agents.	the susceptibility of giardia lamblia to eight chemotherapeutic agents was studied in vitro. the criteria of viability of the parasite was the ability of the parasite to attach to the coverslip surface in situ, and to multiply in drug free media on subcultures. the giardicidal and 50% inhibitory concentrations of each drug were measured. the activity of metronidazole in vitro was found to be similar to that of mepacrine, whilst that of chloroquine was inferior. the sensitivity of g. lamblia to m ...	1998	9914672
evaluation of laboratory techniques for diagnosis of amoebiasis.	evaluation of 82 cases of amoebiasis including 4 of liver abscess was done. microscopy of 62 stool samples revealed trophozoites in 19 (30.6%) and cysts in 8 (12.9%). pva preserved samples were stained by iron-hamatoxylin and trichrome. twenty-nine samples (46.7%) were positive by culture on endamoeba, nih and charcoal agar. additional two culture positive cases were negative by direct microscopy. three (75%) samples of liver abscess pus were culture positive. of the sera screened for amoebic an ...	1998	9914676
amoebapore homologs of caenorhabditis elegans.	it is shown that the caenorhabditis elegans genome contains several distantly related members of the gene family of saposin-like proteins. the putative products of genes t07c4.4, t08a9.7a, t08a9.7b, t08a9.8, t08a9.9, t08a9.10 are similar to the amoebapores of entamoeba histolytica, granulysin of cytotoxic t lymphocytes and a putative amoebapore-related protein of the liver fluke fasciola hepatica inasmuch as they consist of only a single saposin-like domain and a secretory signal peptide. the sa ...	1998	9920402
cloning and bacterial expression of adenosine-5'-triphosphate sulfurylase from the enteric protozoan parasite entamoeba histolytica.	a gene encoding adenosine-5'-triphosphate sulfurylase (as) was cloned from the enteric protozoan parasite entamoeba histolytica by polymerase chain reaction using degenerate oligonucleotide primers corresponding to conserved regions of the protein from a variety of organisms. the deduced amino acid sequence of e. histolytica as revealed a calculated molecular mass of 47925 da and an unusual basic pi of 9.38. the amebic protein sequence showed 23-48% identities with as from bacteria, yeasts, fung ...	1998	9920405
[laboratory diagnosis of protozoan and parasitic infections. 1. protozoan infections. b. amebic dysentery].		1998	9921248
overdiagnosis of intestinal amoebiasis associated to serial microscopical examination of faeces. some precisions on a problem.		1998	9921305
interactions between epithelial cells and immune cells in the intestine.	not merely a passive barrier as previously assumed, epithelial cells act as sensitive indicators of infection that initiate defense responses. noninvasive as well as invasive organisms have been demonstrated to elicit production of chemoattractants. that noninvasive organisms have this capacity suggests that receptor-mediated signaling pathways may be involved. epithelial cells have been found to release both chemokines and cytokines in a precise mixture that varies according to the origin or ma ...	1998	9928368
anaemia and intestinal parasitic infections among school age children in behera governorate, egypt. behera survey team.	anaemia is considered a serious public health problem in egypt, although updated population-based data are lacking. similarly, data on prevalence and intensity of infection with intestinal parasites, which are considered one possible cause of anaemia, are available only from small, unrepresentative sample surveys. the present research was implemented on an entire governorate representative sample. the aim of the study was to assess the prevalence of anaemia and intestinal parasites in the area a ...	1998	9972072
henoch schönlein purpura and amebiasis.	the pathogenesis of henoch schönlein purpura (hsp) is unknown but is believed to result from an immune complex reaction to various antigenic stimuli, such as infectious agents. however, its association with entamoeba histolytica has not been reported before. we present an 11-year-old boy with hsp, confirmed by the demonstration of leukocytoclastic vasculitis from skin and diffuse endocapillary proliferative glomerulonephritis, together with immunoglobulin a and complement component c3 deposition ...	1998	9821714
host-pathogen interaction in amebiasis and progress in vaccine development.	entamoeba histolytica, the causative organism of invasive intestinal and extraintestinal amebiasis, infects approximately 50 million people each year, causing an estimated 40 to 100 thousand deaths annually. because amebae only infect humans and some higher non-human primates, an anti-amebic vaccine could theoretically eradicate the organism. uncontrolled epidemiologic studies indicate that acquired immunity to amebic infection probably occurs and that such a vaccine might be feasible. applicati ...	1998	9832261
epithelial cell-initiated inflammation plays a crucial role in early tissue damage in amebic infection of human intestine.	entamoeba histolytica infection of the intestine can induce severe gut inflammation. the aims of this study were to assess the role of the host inflammatory response in the tissue damage observed with amebiasis and the role of the intestinal epithelial cell in initiating that response.	1998	9834272
case report: a patient who developed an amoebic liver abscess during treatment with interferon.	a 65-year-old female received recombinant interferon (ifn) alpha-2b daily for the treatment of chronic hepatitis c. fever (39 degrees c or higher) developed 14 days after the start of administration. abdominal computed tomography suggested multiple liver abscesses, which had not been detected before ifn administration. an autopsy revealed an amoebic liver abscess. a subclinical infection of entamoeba histolytica in this case developed into amoebic liver abscess during ifn administration.	1998	9835326
amoebic relaxant derived factor with activity on vascular smooth muscle.		1998	9836255
mucosal and systemic suppression of the immune response to e. histolytica provoked by metronidazole and mebendazole in balb/c mice.		1998	9836259
prevalence and epidemiologic characteristics of opportunistic and non-opportunistic intestinal parasitic infections in hiv positive patients in manipur.	a survey of the intestinal parasites among the hiv positive asymptomatic injecting drug users (idus) in manipur state in north-east india revealed the presence of three protozoan and two nematode species. of these, the two opportunistic parasitic protozoans i.e., cryptosporidium sp. (94.4 percent) and isospora sp. (10.7 percent) were predominant over entamoeba histolytica (5.6 percent), while non-opportunistic parasitic nematodes, i.e. ascaris lumbricoides (4.6 percent) and ancylostoma sp. (1 pe ...	1998	9842160
[validation in havana city, cuba of enzymeba, an immunoassay for detecting entamoeba histolytica in feces].	parasitologists from different medical institutions in havana city carried out the external validation of enzymeba, a diagnostic procedure of intestinal amebiasis developed at the "pedro kourí" institute of tropical medicine. to this end, serial faeces specimens from 212 individuals were collected and observed on the microscope (reference test). the enzymeba immunoassay (validation test) was also made. on comparing enzymeba with the microscopic examination, satisfactory indexes of sensitivity an ...	1998	9842262
the pyrophosphate-dependent phosphofructokinase of the protist, trichomonas vaginalis, and the evolutionary relationships of protist phosphofructokinases.	the pyrophosphate-dependent phosphofructokinase (ppi-pfk) of the amitochondriate protist trichomonas vaginalis has been purified. the enzyme is a homotetramer of about 50 kda subunits and is not subject to allosteric regulation. the protein was fragmented and a number of peptides were sequenced. based on this information a pcr product was obtained from t. vaginalis gdna and used to isolate corresponding cdna and gdna clones. southern analysis indicated the presence of five genes. one open readin ...	1998	9847416
royal society of tropical medicine and hygiene meeting at manson house, london, 19 february 1998. amoebic disease. entamoeba dispar, an organism reborn.	entamoeba dispar was described by emile brumpt in 1925, and was promptly dismissed as a synonym of e. histolytica by almost all his contemporaries. in the 1970s, however, evidence began to accumulate indicating that brumpt may have been correct and e. dispar is now accepted as a distinct species. this review introduces the organism's history and briefly summarizes what we currently know about its biology. the acceptance of e. dispar has profound implications for our understanding of the epidemio ...	1998	9850382
effect of bacterial association on virulence of entamoeba histolytica to baby hamster kidney cell monolayers.	axenic e. histolytica trophozoite strain nih:200 and hmi:imss when co-associated with aerobic bacteria escherichia coli strain k12 and serotype 056 showed marked increase in virulence as observed by destruction of baby hamster kidney (bhk) monolayers. however, when incubated with anaerobic bacterial strains clostridium perfringens and bacteroides fragilis virulence remained unaltered. further, adherence of e. histolytica to bhk monolayer was found to be mediated by n-acetyl-d-galactosamine.	1998	9854433
the novel core promoter element gaac in the hgl5 gene of entamoeba histolytica is able to direct a transcription start site independent of tata or initiator regions.	entamoeba histolytica, an enteric protozoa, is the third leading parasitic cause of death worldwide. investigation of the transcriptional machinery of this eukaryotic pathogen has revealed an unusual core promoter structure that consists of nonconsensus tata and initiator regions and a novel third conserved core promoter sequence, the gaac element. mutation of this region in the hgl5 promoter decreases reporter gene expression and alters the transcription start site. using positional analysis of ...	1998	9705300
effects of aphidicolin on entamoeba histolytica growth and dna synthesis.	we have previously demonstrated that dna polymerase activity of entamoeba histolytica is inhibited by aphidicolin, which is a specific inhibitor of eukaryotic nuclear replicative dna polymerases. the present study was aimed to evaluate the effect of aphidicolin on growth and dna synthesis by this parasite. aphidicolin blocked the growth of axenic e. histolytica strain hm-1:imss. dna synthesis was also inhibited by aphidicolin when assayed by incorporation of [3h]thymidine into the dna. the inhib ...	1998	9714225
substructural specificity and polyvalent carbohydrate recognition by the entamoeba histolytica and rat hepatic n-acetylgalactosamine/galactose lectins.	both the entamoeba histolytica lectin, a virulence factor for the causative agent of amebiasis, and the mammalian hepatic lectin bind to n-acetylgalactosamine (galnac) and galactose (gal) nonreducing termini on oligosaccharides, with preference for galnac. polyvalent galnac-derivatized neoglycoproteins have >1000-fold enhanced binding affinity for both lectins (adler,p., wood,s.j., lee,y.c., lee,r.t., petri,w.a.,jr. and schnaar,r.l.,1995, j. biol. chem ., 270, 5164-5171). substructural specifici ...	1998	9719685
identification and characterisation of early reactions of asparagine-linked oligosaccharide assembly in entamoeba histolytica.	sequential incubation of a mixed membrane fraction isolated from entamoeba histolytica trophozoites with the nonionic detergents brij 35 and igepal ca-630 rendered a soluble fraction with the ability to transfer n-acetylglucosamine (glcnac) from udp-glcnac to dolichol phosphate to form a lipid saccharide that was identified as a mixture of dolichol-p-p-glcnac and dolichol-p-p-(glcnac)2 as follows. (a) the reaction occurred only in the presence of exogenously added dolichol phosphate and was stro ...	1998	9770617
simultaneous amoebic liver abscess and hepatitis a infection.	hepatitis a virus (hav) infection and amoebic liver abscess have an identical mode of transmission (fecal-oral route) and similar epidemiology. either of these diseases might be considered in patients presenting with clinical signs and symptoms of liver disease in areas of the world where hepatitis and entamoeba histolytica are endemic. the following two cases describe patients with simultaneous infection of hav and amoebic liver abscess. this report emphasizes the role of dual infection in pati ...	1998	9772324
diagnosis of trichomonas vaginalis infection by pcr using vaginal swab samples.	trichomonas vaginalis infection is the most prevalent nonviral sexually transmitted disease (std) in the world. a pcr test using vaginal swab samples for the detection of t. vaginalis was developed to add t. vaginalis infection to the growing list of stds that can be detected by dna amplification techniques. a primer set, btub 9/2, was designed to target a well-conserved region in the beta-tubulin genes of t. vaginalis. all strains (15 of 15) of t. vaginalis tested were successfully detected by ...	1998	9774566
intestinal amoebiasis: antibody-secreting cells and humoral antibodies.	splenic plasma cell response and systemic antibody response to intestinal amoebiasis were studied in c3h/hej mice from 5 to 60 days post-inoculation with entamoeba histolytica. at various time intervals specific antibody-secreting cells (asc) in the spleen were measured in infected mice and non-infected control mice by enzyme-linked immunospot (elispot) assay. serum antibodies were measured by enzyme-linked immunosorbent assay (elisa). the infected animals showed high iga asc from 30 to 50 days ...	1998	9775574
some gastro-intestinal parasites of zoonotic (public health) importance commonly observed in old world non-human primates in kenya.	a study was undertaken to categorise some gastro-intestinal (git) parasites commonly observed in kenyan non-human primates (nhps) on the basis of their health implications for humans. six species of locally available non-human primates, namely olive baboons (papio cyanocephalus anubis), vervet monkey (cercopithecus aethiops), sykes monkey (cercopithecus mitis), black and white colobus (colobus abyssinicus), debrazzas monkey (cercopithecus neglectus) and grey and black mangabeys (cercocebus torqu ...	1998	9776144
involvement of the actin cytoskeleton and p21rho-family gtpases in the pathogenesis of the human protozoan parasite entamoeba histolytica.	it has been estimated that infection with the enteric protozoan parasite entamoeba histolytica kills more than 50,000 people a year. central to the pathogenesis of this organism is its ability to directly lyse host cells and cause tissue destruction. amebic lesions show evidence of cell lysis, tissue necrosis, and damage to the extracellular matrix. the specific molecular mechanisms by which these events are initiated, transmitted, and effected are just beginning to be uncovered. in this article ...	1998	9777011
pna molecular beacons for rapid detection of pcr amplicons.	the authors have developed a method for rapid detection of polymerase chain reaction (pcr) amplicons based on surface immobilized pna-dna hybrid probes ('molecular beacons') that undergo a fluorescent-linked conformational change in the presence of a complementary dna target. amplicons can be detected by simply adding a pcr reaction to a microtitre-well containing the previously immobilized probe, and reading the generated fluorescence. no further transfers or washing steps are involved. the aut ...	1998	9727198
disparate amoebae.		1998	9734879
seropositivity for and intestinal colonization with entamoeba histolytica and entamoeba dispar in individuals in northeastern brazil.	in a slum community in northeastern brazil 20% of a sample population was colonized with entamoeba histolytica or entamoeba dispar and 10.6% was colonized with e. histolytica alone. no correlation between seropositivity for anti-ga1nac lectin antibody and colonization was found. these results suggest that colonization does not necessarily produce immunity to reinfection.	1998	9738064
hepatic amebiasis among patients in a public teaching hospital.	the increase in immigration to the united states is associated with diseases, such as amebiasis, that are endemic to developing countries. we retrospectively reviewed 49 public-hospital patients with hepatic amebiasis occurring between 1985 and 1995. most patients were immigrants (47) from latin america (43), male (43), and young (mean age, 39.8 years). symptoms noted by more than half were abdominal pain and fever. ultrasonography showed single lesions in 70% and right-sided involvement in 85%. ...	1998	9743053
prevalence of intestinal parasites among children in southern sudan.	a study was conducted in southern sudan to determine the prevalence of intestinal parasites among school children. a total of 275 stool samples which were examined using formol-ether concentration techniques yielded 15 different species of parasites. hook worm with a prevalence of 13.1% was the predominant nematode followed by strongyloides stercoralis (3.3%), trichostrongylus (2.5%), schistosoma mansoni (2.2%) and trichuris trichiura (1.8%). ascaris lumbricoides and cestodes were not detected i ...	1998	9747000
identification of the 150-kda surface antigen of entamoeba histolytica as a galactose- and n-acetyl-d-galactosamine-inhibitable lectin.	a monoclonal antibody that reacts with a 150-kda protein of entamoeba histolytica on western immunoblotting under nonreducing conditions inhibits the adherence and cytotoxicity of the ameba to mammalian cells in vitro. affinity purification of solubilized trophozoites using the monoclonal antibody and electrophoresis yielded three glycoproteins with molecular masses of 150, 170, and 260 kda, suggesting the existence of either a common epitope or the close association of these proteins. the 260-k ...	1998	9747935
an upstream regulatory element containing two nine basepair repeats regulates expression of the entamoeba histolytica hgl5 lectin gene.		1998	9747982
development of monoclonal antibodies specifically recognizing the cyst stage of entamoeba histolytica.	protozoan cysts were isolated according to a two-step sucrose gradient procedure. pure cysts of entamoeba histolytica, in fixed and native states, were injected into balb/c mice intraperitoneally for immunization. the spleens of these animals were used for fusion with ag8 mouse myeloma cells. hybridomas were obtained and tested for the recognition of e. histolytica, e. dispar, e. coli, e. hartmanni, endolimax nana, jodamoeba biitschlii, and giardia lamblia. three monoclonal antibodies were ident ...	1998	9749623
serum igm antibody response to the galactose-inhibitable adherence lectin of entameoba histolytica.	an elisa for detection of serum igm antibodies to the galactose-inhibitable adherence lectin of entamoeba histolytica revealed that 2.8% of uninfected controls, 0.0% of controls infected with other parasites, 13.4% of asymptomatic amebic infections, 55% of colitis patients, and 77% of amebic liver abscess patients from cairo, egypt and durban, south africa had serum anti-lectin igm antibodies. of acute amebic colitis patients with symptoms for less than one week, only 6% possessed serum igg anti ...	1998	9749639
[a case of intestinal amebiasis].		1998	9750051
an essential methionine residue involved in substrate binding by phosphofructokinases.	an alignment of all ppi-dependent phosphofructokinases and all allosteric atp-dependent pfks shows relatively few residues that are fully conserved. one residue that is conserved is a methionine residue that appears from the crystal structure of escherichia coli pfk to be interacting with fructose 6-p. very conservative substitutions for this methionine with leucine or isoleucine by site-directed mutagenesis of e. coli atp-pfk and entamoeba histolytica ppi-pfk produced profound decreases either ...	1998	9753654
[cytoskeletal actin and its associated proteins. some examples in protista].	many processes, cell motility being an example, require cells to remodel the actin cytoskeleton in response to both intracellular and extracellular signals. reorganization of the actin cytoskeleton involves the rapid disassembly and reassembly of actin filaments, a phenomenon regulated by the action of particular actin-binding proteins. in recent years, an interest in studying actin regulation in unicellular organisms has arisen. parasitic protozoan are among these organisms and studies of the c ...	1998	9754306
schistosoma mansoni, intestinal parasites and perceived morbidity indicators in schoolchildren in a rural endemic area of western côte d'ivoire.	there is a great need for rapid and low-cost identification of communities at high risk of intestinal schistosomiasis. we report the development of a questionnaire approach that may do so. in the first phase, 209 schoolchildren from 3 neighbouring villages in a rural area endemic for intestinal schistosomiasis in western côte d'ivoire were screened for schistosoma mansoni and other helminths on 4 consecutive days using kato-katz thick smears. daily infection prevalences of s. mansoni were high ( ...	1998	9754666
helminth and protozoan gastrointestinal tract parasites in captive and wild-trapped african non-human primates.	the objective of this study was to investigate the gastro-intestinal (git) parasites commonly occurring in captive and wild-trapped (wt) non-human primates (baboons, vervets and sykes) in kenya and compare their prevalence. three hundred and fifteen faecal samples were subjected to a battery of diagnostic tests, namely, direct smear, modified formal ether sedimentation, kato thick smear, harada-mori techniques for parasite detection and culture to facilitate nematode larvae identification. of th ...	1998	9760061
[intestinal parasitism in a parakanã indigenous community in southwestern pará state, brazil].	to determine the occurrence and epidemiological aspects of intestinal parasites among the parakanã indigenous people in the paranatinga settlement (in the eastern amazon region), parasitological tests were performed in april 1992 and february 1995. one fresh stool specimen was obtained and immediately processed using the hoffman and direct methods. some 126 samples were obtained in april 1992 (from a total population of 215 individuals). some 80. 2% (101) of those tested were infected with at le ...	1998	9761604
[amebiasis--a differential diagnosis from inflammatory bowel disease].	entamoeba histolytica is a very uncommon etiology of travelers diarrhoea, but may be an important differential diagnosis to inflammatory bowel disease. a misdiagnosis of amoebic colitis as inflammatory bowel disease followed by inadvertent treatment with corticosteroids may be fatal. current techniques for the diagnosis of amoebiasis include stool studies, endoscopic biopsy and serology. demonstration of haematophagous trophozoites in feces or in tissue biopsy is the definitive method for diagno ...	1998	9763927
antiamoebic and phytochemical screening of some congolese medicinal plants.	results from the in vitro antiamoebic activity of some congolese plant extracts used as antidiarrhoeic in traditional medicine indicated that of 45 plant extracts tested, 35 (77.78%) exhibited an antiamoebic activity and 10 (22.22%) were inactive. the highest activity (mic < 100 microg/ml) was obtained with extracts from root bark of paropsia brazzeana, cryptolepis sanguinolenta, alchornea cordifolia, hensia pulchella, maprounea africana, rauwolfia obscura and voacanga africana, leaves and stem ...	1998	9687082
regulation of adherence and virulence by the entamoeba histolytica lectin cytoplasmic domain, which contains a beta2 integrin motif.	killing of human cells by the parasite entamoeba histolytica requires adherence via an amebic cell surface lectin. lectin activity in the parasite is regulated by inside-out signaling. the lectin cytoplasmic domain has sequence identity with a region of the beta2 integrin cytoplasmic tail implicated in regulation of integrin-mediated adhesion. intracellular expression of a fusion protein containing the cytoplasmic domain of the lectin has a dominant negative effect on extracellular lectin-mediat ...	1998	9693367
application of lactophenol cotton blue for identification and preservation of intestinal parasites in faecal wet mounts.	wet mounting is the simplest and easiest technique for the examination of faeces. routinely employed wet mounts in most of the laboratories include saline, iodine and buffered methylene blue. lactophenol cotton blue [lcb] staining--mounting medium is commonly used for microscopic identification of fungi. lcb and its modifications were tested as staining mounting medium on parasite positive faecal samples [both fresh as well as formalin fixed] to stain and demonstrate morphology and to preserve p ...	1998	9670627
isolation and molecular characterization of a surface-bound proteinase of entamoeba histolytica.	major pathogenic functions of entamoeba histolytica involved in destruction of host tissues are the degradation of extracellular matrix proteins mediated by secreted cysteine proteinases and contact-dependent killing of host cells via membrane-active factors. a soluble protein with an affinity for membranes was purified from amoebic extracts to apparent homogeneity. n-terminal sequencing and subsequent molecular cloning of the factor revealed that it is a member of the cysteine proteinase family ...	1998	9484883
prevalence of intestinal parasites in rural southern indians.	to determine the prevalence of intestinal protozoal and helminthic infection in a rural population.	1998	9484973
recombinant expression and biochemical characterization of an nadph:flavin oxidoreductase from entamoeba histolytica.	the gene encoding a putative nadph:flavin oxidoreductase of the protozoan parasite entamoeba histolytica (eh34) was recombinantly expressed in escherichia coli. the purified recombinant protein (receh34) has a molecular mass of about 35 kda upon sds/page analysis, exhibits a flavoprotein-like absorption spectrum and contains 1 mol of non-covalently bound fmn per mol of protein. receh34 reveals two different enzymic activities. it catalyses the nadph-dependent reduction of oxygen to hydrogen pero ...	1998	9494088