Publications

application of local products r-phycoerythrin and monoclonal antibody as a fluorescent antibody probe to detect entamoeba histolytica trophozoites.	r-phycoerythrin (r-pe) was extracted from red algae, gracilaria fisheri from pattani province, thailand, with 50 mm sodium phosphate buffer, ph 7.0, followed by precipitation with 30-50% final concentration of saturated ammonium sulphate solution at 0 degree c. the precipitate was further purified by deae-cellulose (de-52) column chromatography. the purified r-pe showed a single band of mr 240 kda by polyacrylamide gel electrophoresis with the maximum absorption and maximum fluorescence emission ...	1996	9279993
gene amplification in entamoeba histolytica.	we show here data suggesting that entamoeba histolytica, the protozoan responsible for human amebiasis, presents dna amplification in a fashion similar to that described for transformed mammalian cells. by transmission electron microscopy (tem), we found linear, circular and concentric circular dna molecules exhibiting the main events of the unscheduled dna amplification process. loops were formed after the recombination of two nonadjacent dna regions, and bubbles appeared from the recombinant s ...	1996	9371226
comparative evaluation of somatic & excretory-secretory antigens of entamoeba histolytica in serodiagnosis of human amoebiasis by elisa.	the excretory-secretory antigens collected from the axenic culture medium and conventional somatic antigen prepared from the whole trophozoites of e. histolytica were compared for their efficacy in serodiagnosis of amoebiasis. a total of 280 sera collected from different clinically proven cases of amoebiasis and healthy subjects were analysed against both the antigens in elisa. both antigens showed a 100 per cent correlation in amoebic liver abscess cases, patients infected with enteropathogens ...	1996	8783520
partial purification and characterization of ornithine decarboxylase from entamoeba histolytica.	multiplication of e. histolytica was accompanied by a parallel increase in ornithine decarboxylase (odc) specific activity up to 72 h of cultivation in tyi-s-33 medium. thereafter, activity rapidly decayed whereas growth continued for another 24 h before entering into the stationary growth phase. odc was very unstable. partial purification (14-fold) of the enzyme was achieved by a three-step procedure involving high-speed centrifugation, gel filtration and adsorption to hydroxylapatite. the part ...	1996	8786214
molecular evolution of the 14-3-3 protein family.	members of the highly conserved and ubiquitous 14-3-3 protein family modulate a wide variety of cellular processes. to determine the evolutionary relationships among specific 14-3-3 proteins in different plant, animal, and fungal species and to initiate a predictive analysis of isoform-specific differences in light of the latest functional and structural studies of 14-3-3, multiple alignments were constructed from forty-six 14-3-3 sequences retrieved from the genbank and swissprot databases and ...	1996	8798343
sequence-specific detection of pcr-amplified dna by restriction enzyme release of hybrids.	we have developed a method to detect pcr amplicons that contain a restriction enzyme site. the method is called polymerase chain reaction-hybridization and enzymatic release assay (pcr-hera). the pcr product is hybridized to a synthetic oligonucleotide that is immobilized on a microtitre plate. specific cleavage of the resulting hybrid by a restriction endonuclease liberates a fluorescein labeled arm of the immobilized dna. we demonstrate the use of pcr-hera to detect species-specific sequences ...	1996	8799371
entamoeba histolytica: proteinase secretion induced by collagen type i is dependent on cytoskeleton integrity.	proteolytic activities of the protozoan parasite entamoeba histolytica strain hm1:imss and the cytochalasin d-resistant mutant bg-3 were analyzed following stimulation with collagen type i and ca2+, which induces electron-dense associated collagenase secretion. the mutant bg-3 had a protease activity of 73 kda and secretion of total protease activity was not stimulated by collagen type i and ca2+, which produced, in contrast, a 2-fold increase in protease secretion by the parental strain. this c ...	1996	8801549
intestinal parasites among the southeast asian laborers in taiwan during 1993-1994.	a large number of foreign laborers are now working in taiwan, the majority coming from southeast asia where parasitic infections are common. since 1992, monitoring the intestinal parasitic infections of these foreigners has been carried out, particularly to prevent the introduction of some of the parasites into taiwan. this paper reports results obtained during the year 1993-1994.	1996	8803301
relative importance of inositol (1,4,5)trisphosphate and inositol (1,3,4,5)tetrakisphosphate in entamoeba histolytica.	[3h]inositol tetrakisphosphate (ins(1,3,4,5)p4) binding sites which were poorly displaced by unlabelled inositol (1,4,5)-trisphosphate (ins(1,4,5)p3) were detected in membrane fractions of entamoeba histolytica. similarly, unlabelled ins(1,3,4,5)p4 was 30-fold less efficient in displacing [3h]ins(1,4,5)p3 binding. ph sensitivities of binding of the two isomers were markedly different. scatchard analysis of the data revealed single binding sites and similar receptor densities for each of the two ...	1996	8804436
analysis of 69 patients with amebic liver abscess.	all 69 patients with amebic liver abscess that we treated in 1981-1992 were studied retrospectively. men predominated by a 10:1 ratio. of our 227 patients with amebiasis, some 30% yearly had liver involvement. the incidence peaked in 1988, decreasing later but increasing again in 1992. most patients were 30-50 years old, the overall mean age being 45 years (range, 22-79), and decreasing with time. patients with the related factors of travel abroad, positive results of a test for treponema pallid ...	1996	8808427
sequence of a giardia lamblia gene coding for the glycolytic enzyme, pyruvate,phosphate dikinase.	the sequence of the gene coding for pyruvate,phosphate dikinase (ec 2.7.9.1) in giardia lamblia (syn. g. duodenalis) has been established. the deduced amino acid sequence is very similar to all of its known homologs from the protist, entamoeba histolytica, the eubacterium, clostridium symbiosum and plant chloroplasts. phylogenetic reconstruction with neighbor-joining and maximum parsimony methods reveals that the sequences form two clades, one comprising the anaerobic microorganisms, and the oth ...	1996	8813667
a homologue of the cysteine proteinase gene (acp1 or eh-cpp3) of pathogenic entamoeba histolytica is present in non-pathogenic e. dispar strains.	one of the three cysteine proteinase genes, acp1 (or cp 3), has been reported to be missing in non-pathogenic strains of entamoeba histolytica (or entamoeba dispar as recently labeled). unexpectedly, a gene fragment very similar in its sequence (95% homology) to acp1 of pathogenic strains was obtained by use of the polymerase chain reaction from genomic dna and cdna of various cloned non-pathogenic strains as well as in 23 clinical isolates from asymptomatic carriers. the finding of the acp1 hom ...	1996	8813676
upstream regulatory elements controlling expression of the entamoeba histolytica lectin.	entamoeba histolytica genomic organization and putative promoter elements appear to be distinct from both metazoan and better characterized protozoan organisms. the recent development of dna-mediated transfection for e. histolytica enabled characterization of cis-acting promoter elements required for gene expression. a deletion and replacement analysis was conducted on the promoter of an e. histolytica gene encoding the heavy subunit of the n-acetyl-beta-d-galactosamine-specific adhesin (hgl5). ...	1996	8813680
cloning and characterization of the entamoeba histolytica pyruvate: ferredoxin oxidoreductase gene.		1996	8813698
recombinant antigen-based avidin-biotin microtiter enzyme-linked immunosorbent assay for serodiagnosis of invasive amebiasis.	an immunoscreening approach was used to isolate a strongly positive cdna clone from an entamoeba histolytica hk-9 cdna expression library in the phage vector lambda zap-ii. the 1.85-kb cdna insert was found to be truncated and encoded the cysteine-rich, immunodominant domain of the antigenic 170-kda subunit of the amebal galactose-n-acetylgalactosamine binding lectin. this domain was expressed as a glutathione s-transferase fusion protein in escherichia coli. inclusion bodies of the recombinant ...	1996	8815092
differentiation of korean isolates of entamoeba histolytica from entamoeba dispar.	cysts of entamoeba histolytica are still found from humans in korea, but not all of the cysts are known as pathogenic. the non-pathogenic strain is regarded as a different species, e. dispar. in this study, korean isolates of conventional e. histolytica were subjected for the differentiation by polymerase chain reaction (pcr) and restriction fragment length polymorphism (rflp) analysis. human stools were screened by routine microscopic examination, and cyst or trophozoite positive stools were in ...	1996	8820737
physical mapping and expression of gene families encoding the n-acetyl d-galactosamine adherence lectin of entamoeba histolytica.	adherence of the enteric protozoan parasite entamoeba histolytica is mediated by an n-acetyl d-galactosamine (galnac)-specific lectin, a heterodimer of heavy (170 kda) and light (35/31 kda) subunits. the gene families encoding the lectin subunits were characterized using clamped homogeneous electric field (chef) gel electrophoresis in the strain hm1:imss. the heavy subunit was shown to be encoded by a family of five hgl genes, which were physically mapped to five distinct hindiii restriction fra ...	1996	8821939
[invasive amebiasis at an institution for the mentally retarded in shizuoka prefecture].	amebiasis caused by entamoeba histolytica at an institution for mentally retarded in shizuoka prefecture is reported. five of the 50 patients showed e. histolytica cysts in their stools and 4 were positive serologically. the polymerase chain reaction and restriction fragment length polymorphism revealed that the isolates were pathogenic-type e. histolytica. epidemiological analysis revealed that the amebic infection was caused by the abnormal behavior of mentally retarded patients. administratio ...	1996	8822047
a gene highly homologous to acp1 encoding cysteine proteinase 3 in entamoeba histolytica is present and expressed in e. dispar.	we have cloned the complete gene encoding cysteine proteinase 3 in e. histolytica as well as a cdna encoding a highly homologous protein in e. dispar. in addition, we have demonstrated the presence and expression of the cp3 gene in various e. histolytica and e. dispar isolates. since the expression of the gene is rather similar within both entamoeba species, we assume that it does not constitute the proposed virulence factor of e. histolytica.	1996	8825217
detection and characterization of dna polymerase activity in entamoeba histolytica.	dna polymerase activity was detected and characterized in nuclear extracts from trophozoites of entamoeba histolytica. the activity was high at ph 2 to ph 6, but at ph 8 and 10 the activity was very low. the presence of k+ was inhibitory for the activity and a higher concentration of k+ markedly inhibited the activity. magnesium ions (mg2+) were absolutely required for activity and its optimal concentration was 6 to 8 mm. the activity was markedly inhibited by aphidicolin which is an inhibitor o ...	1996	8825452
recent advances in amebiasis.	advancements in our understanding of amebiasis have been rapid over the decade that i have followed this field. what was identified morphologically for years as entamoeba histolytica has been redescribed with modern techniques as a complex of two species, the commensal parasite e. dispar and the pathogenic parasite e. histolytica that is the cause of colitis and liver abscess. antigen detection tests are now available for the rapid detection in stool of the pathogenic species e. histolytica. new ...	1996	8833626
pcr-based quantitation of transfected luciferase dna: evaluation using an entamoeba histolytica reporter construct.		1996	8723913
role of signalling and cytoskeletal rearrangements in the pathogenesis of entamoeba histolytica.	virulence of entamoeba histolytica is characterized by intestinal tissue invasion, engulfment of host cells and the formation of liver abscesses. the actin-rich cytoskeleton of the amoeba allows rapid changes in morphology in response to signals from external stimuli. cellular and molecular studies have described some of the proteins that participate in signalling and in cytoskeletal changes.	1996	8727599
phylogenetic analysis of beta-tubulin sequences from amitochondrial protozoa.	it has been proposed that certain extant anaerobic protozoa are descended from organisms that diverged early in eukaryotic evolution prior to the acquisition of mitochondria. among these are the extracellular parasites giardia lamblia, trichomonas vaginalis, and entamoeba histolytica, and the obligately intracellular microsporidia. phylogenetic analysis of rrna sequences from these amitochondrial organisms suggests that g. lamblia, t. vaginalis, and microsporidia are near the base of the eukaryo ...	1996	8728394
intestinal parasites of humans in a highland community of irian jaya, indonesia.	an indigenous, highland community in the oksibil valley of irian jaya, indonesia, was examined on two occasions to determine the prevalence of intestinal parasites. overall, 478 subjects from three villages in the study area, about 10% of the available population, were sampled. using a standard, wet-mount technique, 15 different species of parasites were found. hookworm was predominant in all age groups, with prevalences of 51%-86%, followed by ascaris lumbricoides (46%-57%) and trichuris trichi ...	1996	8729627
oral immunization with an attenuated vaccine strain of salmonella typhimurium expressing the serine-rich entamoeba histolytica protein induces an antiamebic immune response and protects gerbils from amebic liver abscess.	attenuated salmonellae represent attractive candidates for the delivery of foreign antigens by oral vaccination. in this report, we describe the high-level expression of a recombinant fusion protein containing the serine-rich entamoeba histolytica protein (srehp), a protective antigen derived from virulent amebae, and a bacterially derived maltose-binding protein (mbp) in an attenuated strain of salmonella typhimurium. mice and gerbils immunized with s. typhimurium expressing srehp-mbp produced ...	1996	8613356
fibronectin-induced intracellular calcium rise in entamoeba histolytica trophozoites: effect on adhesion and the actin cytoskeleton.	the interaction of entamoeba histolytica trophozoites with fibronectin (fn) promotes adhesion of the protein to the cells and its later degradation by locally released proteases. binding to fn-covered surfaces induces, in addition, the formation of actin adhesion plates and focal contacts in the amebas. the signaling mechanisms underlying the response to fn are incompletely understood. in this paper we examined the modifications of cytosolic free calcium ([ca2+]i) induced in the trophozoites by ...	1996	8617326
entamoeba histolytica: isoprenylation of p21ras and p21rap in vitro.		1996	8617332
entamoeba histolytica: involvement of pp125fak in collagen-induced signal transduction.	the interaction of entamoeba histolytica trophozoites with collagen involves cell adherence, formation, and release of electron dense granules (edgs) containing collagenase activity leading to the degradation of the bound protein. the binding is thought to be mediated by an "integrin-like" collagen receptor. since the signal transduction mechanisms triggered by the collagen-trophozoite interaction are unknown, but clearly involve cytoskeletal organization, we decided to explore the role of prote ...	1996	8617343
entamoeba histolytica: localization of a 30-kda cysteine proteinase using a monoclonal antibody.	we produced a monoclonal antibody against a major cysteine proteinase of 30kda from trophozoites of entamoeba histolytica strain hm1:imss. the specificity of the monoclonal antibody was confirmed by specific inhibition of azocasein digestion and by electrophoretic analysis, in the presence of sodium dodecyl sulfate or on a substrate gel, of the antigen precipitated by the antibody. immunofluorescent staining of trophozoites with the monoclonal antibody revealed heterogeneity in the intensity of ...	1996	8617344
[the role of aminoglycosides in hiv-infected patients].	the frequency of serious infections due to pseudomonas aeruginosa is increasing among patients with advanced hiv infection; most of the cases are community-acquired. early diagnosis and adequate treatment--usually with the combination of an anti-pseudomonas beta-lactam antibiotic and an aminoglycoside--have a crucial bearing on prognosis. the good in vitro activity of aminoglycosides against mycobacteria contrasts with the need for intravenous administration and toxicity. in patients with mycoba ...	1996	8677419
protozoan infections in the male genital tract.	we reviewed the literature on protozoan infections in the male genital tract, with special reference to histopathological findings and their repercussions on different andrological functions.	1996	8683676
amebiasis and the entamoeba histolytica gal/galnac lectin: from lab bench to bedside.		1996	8689398
antiamoebic activity of piper longum fruits against entamoeba histolytica in vitro and in vivo.	the fruits of piper longum used in traditional remedies against intestinal distress have been tested for their efficacy against experimental caecal amoebiasis of rats. the ethanolic extract, hexane fraction, n-butanol soluble fraction exerted in vitro amoebicidal action at 1000 micrograms/ml and the chloroform fraction at 500 micrograms/ml. the ethanolic extract and piperine, a pure compound, from this plant material cured 90% and 40% of rats with caecal amoebiasis, respectively.	1996	8691851
complementation of an escherichia coli adhe mutant by the entamoeba histolytica ehadh2 gene provides a method for the identification of new antiamebic drugs.	the pathogenic protozoan parasite entamoeba histolytica, the cause of amebic dysentery and amebic liver abscess, is an obligate anaerobe, and derives energy from the fermentation of glucose to ethanol with pyruvate and acetyl coenzyme a as intermediates. we have isolated ehadh2, a key enzyme in this pathway, that is a nad+- and fe2+-dependent bifunctional enzyme with acetaldehyde dehydrogenase and alcohol dehydrogenase activities. ehadh2 is the only known eukaryotic member of a newly defined fam ...	1996	8692838
the influence of conserved aromatic residues on the electron transfer reactivity of 2[4fe-4s] ferredoxins.	the detailed mechanism used by [4fe-4s] ferredoxins to exchange electrons is not known. the importance of two highly conserved aromatic residues, each located close to one cluster of 2[4fe-4s] ferredoxins has been probed by site-directed mutagenesis of clostridium pasteurianum ferredoxin. all generated variants are less stable than the native protein and only hydrophobic residues can replace one of the two conserved aromatic residues. with leucine substituting both aromatics, clostridium pasteur ...	1996	8695647
cloning and expression of a putative alcohol dehydrogenase gene of entamoeba histolytica and its application to immunological examination.	to clone and express the genes encoding major antigens of entamoeba histolytica, we constructed a lambda gt11 cdna library for e. histolytica hm1:imss and screened it with pooled sera from patients with amoebiasis. a 1,223-bp cdna was cloned (clone 1223), and its nucleotide sequence was determined. the amino acid sequence predicted to be encoded by the open reading frame of clone 1223 consisted of 396 residues and showed 32.5 and 32.3% homology to the nadh-dependent butanol dehydrogenases i and ...	1996	8705667
oral immunization with a recombinant cysteine-rich section of the entamoeba histolytica galactose-inhibitable lectin elicits an intestinal secretory immunoglobulin a response that has in vitro adherence inhibition activity.	the lc3-encoded 52-kda recombinant protein includes amino acids 758 to 1134 of the 170-kda subunit of the galactose-inhibitable lectin. oral immunization of balb/c mice with the lc3-encoded protein and cholera holotoxin induced an intestinal secretory immunoglobulin a (iga) response (p < 0.01 compared with the control). there was a negative correlation (p = 0.001) between intestinal anti-lc3 iga and serum iga and igg antibody responses. intestinal secretions from immunized mice completely inhibi ...	1996	8606122
cloning and expression of an entamoeba histolytica napd+(-)dependent alcohol dehydrogenase gene.	in this paper we cloned, sequenced and expressed a novel entamoeba histolytica alcohol dehydrogenase gene (ehadh3). ehadh3 has a predicted 383 amino acids open reading frame, encoding for a 42.3 kda protein. the deduced amino acid sequence showed 24 to 26% identity to other type iii alcohol dehydrogenases found in prokaryotic and lower eukaryotic organisms, but not in mammalia. there are at least two ehadh3 gene copies in the genome, but only a 1.2 kb transcript was detected. the ehadh3 fusion p ...	1996	8611619
the effect of chronic intestinal parasitic infection on maternal and perinatal outcome.	the main objective of this prospective cohort study was to investigate the prevalence, risk factors and maternal-perinatal consequences of chronic asymptomatic intestinal parasitic infection during pregnancy.	1996	8620997
[a case of amoebiasis as a latent infection].	a 69-year-old male was admitted because of constipation and abdominal distension. a colon fiberscopic examination revealed the formation of ulceration. the trophozite of entamoeba histolytica was detected from from the specimens of colon mucosal biopsy of the ulcer. the stool was positive for the cysts of e. histolytica too. he had been in china and southeast asia during world war ii. he returned home and experienced amoebic dysentry, and was treated with emethin hydrochlolide. he suffered from ...	1996	8621966
prevalence of enteropathogens in stools of rural maasai children under five years of age in the maasailand region of the kenyan rift valley.	stool samples were collected during august 1994 from seventy rural maasai children under the age of five years who were living in the maasailand region of the kenyan rift valley. microbiological analysis was carried out on these samples to identify which intestinal pathogens were present among the infant population of the maasai. of the samples studied 54% were pathogen positive. the most common pathogen isolated was giardia lamblia which was detected in 31% of the samples. other pathogens that ...	1996	8625866
evidence for the existence of both proteasomes and a novel high molecular weight peptidase in entamoeba histolytica.	to screen for high molecular weight proteases in entamoeba histolytica, we subjected a soluble amebal extract to density gradient centrifugation and tested the fractions for activity against the chymotryptic peptide substrate, suc-leucyl-leucyl-valyl-tyrosyl-4-methylcoumaryl-7-amide. two peaks of activity, of approximately 11 and 20 s, were clearly separated. based on sds-electrophoretic pattern and immunoblot analysis, we ascribe the 20 s activity to proteasomes. the 11 s protein was purified f ...	1996	8626412
replication initiates at multiple dispersed sites in the ribosomal dna plasmid of the protozoan parasite entamoeba histolytica.	in the protozoan parasite entamoeba histolytica (which causes amoebiasis in humans), the rrna genes (rdna) in the nucleus are carried on an extrachromosomal circular plasmid. for strain hm-1:imss, the size of the rdna plasmid is 24.5 kb, and 200 copies per genome are present. each circle contains two rrna transcription units as inverted repeats separated by upstream and downstream spacers. we have studied the replication of this molecule by neutral/neutral two-dimensional gel electrophoresis and ...	1996	8628298
shortened amoebapore analogs with enhanced antibacterial and cytolytic activity.	amoebapores are cytolytic peptides of entamoeba histolytica which function by the formation of ion channels in target cell membranes. three isoforms (amoebapore a, b, and c) exist in amoebic cytoplasmic granules. they are composed of 77 amino acid residues arranged in four alpha-helical domains. in order to analyze the structure-function relationships, 15 synthetic peptides of 24-25 residues were constructed based on the assumption that the third helix is the membrane-penetrating domain and on t ...	1996	8641476
unbiased estimation of symmetrical directional mutation pressure from protein-coding dna.	the most generally applicable procedure for obtaining estimates of the symmetrical, or strandnonspecific, directional mutation pressure (microd) on protein-coding dna sequences is to determine the g+c content at synonymous codon sites (psyn), and to divide psyn by twice the arithmetic mean of the g+c content at synonymous codon sites of a large number of randomly generated, synonymously coding dna sequences (psyn). unfortunately, the original procedure yields biased estimates of psyn and microd ...	1996	8642618
intestinal protozoa.	giardia is the best known cause of protozoal gastrointestinal disease in north america, producing significant but not life-threatening gastrointestinal distress and diarrhea. although diagnosis of giardiasis may be challenging, treatment is usually successful. entamoeba histolytica poses a rarer but far more difficult clinical challenge. dysentery caused by e. histolytica may be the most feared intestinal protozoal infection, although cryptosporidium parvum, balantidium coli, isospora belli, sar ...	1996	8644565
pyrophosphate-dependent phosphofructokinase of entamoeba histolytica: molecular cloning, recombinant expression and inhibition by pyrophosphate analogues.	by using oligonucleotide primers derived from regions highly conserved in prokaryotic and eukaryotic phosphofructokinase sequences, a genomic dna fragment was amplified and used to isolate cdna and genomic clones coding for ppi-dependent phosphofructokinase (ppi-pfk) of entamoeba histolytica. the open reading frame consists of 1308 bp and the corresponding protein has a calculated molecular mass of 47.6 kda. the n-terminal half of the protein shows 27-35% identity with ppi-pfks or atp-dependent ...	1996	8645233
[low digestive hemorrhage caused by amebic colitis].	amebiasis is an infectious disease produced by entamoeba histolytica, which has invasion capacity of the colon mucosa. it has different clinical forms, varying from the asymptomatic carrier state to severe, although not frequent, fulminant or necrotizing colitis, with an important necrosis of the colon mucosa. perforation or intestinal bleeding are possible. we report one case of patient who had a history of recent travel to india. was admitted with a clinical picture of abdominal pain, diarrhea ...	1996	8645519
humoral and mucosal iga antibody response to a recombinant 52-kda cysteine-rich portion of the entamoeba histolytica galactose-inhibitable lectin correlates with detection of native 170-kda lectin antigen in serum of patients with amebic colitis.	humoral and mucosal iga responses to a recombinant cysteine-rich portion (designated lc3) of the entamoeba histolytica galactose-inhibitable lectin's 170-kda subunit were determined in patients with amebic colitis. all patients had 170-kda amebic antigen in serum, compared with 1 of 50 cyst passers and 1 of 31 controls (p < .01). seven days after treatment, serum and fecal 170-kda antigen became undetectable in 12 of the 13 patients (p < .001). serum anti-lc3 iga was found in 83.8% of colitis pa ...	1996	8655985
entamoeba histolytica encodes a highly divergent beta-tubulin.	the microtubules of the amitochondrial parasite entamoeba histolytica are atypical in certain respects. consistent with this, we report that e. histolytica encodes the most divergent beta-tubulin identified to date, with only 54% to 58% identity to beta-tubulins from various species. a similarly divergent beta-tubulin is encoded by the related entamoeba invadens; single gene copies appear to be present in both organisms. the entamoeba sequences were compared with a database of 101 beta-tubulins, ...	1996	8563707
entamoeba histolytica: gene linkage groups and relevant features of its karyotype.	we identified some gene linkage groups in entamoeba histolytica using a 4-m urea improved transversal alternating field electrophoresis (tafe) method. complex rosette-structured dna molecules were found trapped along the gel lanes, explaining the fuzziness of the patterns. using several episomal probes, including 16 s, 5.8 s, and 25 s ribosomal (r)dna genes, an autonomous replication sequence (ars), and ehvr1, we identified a complete ribosomal episome linkage group (celg) at the 1.2-mb position ...	1996	9003315
[synthesis and antiparasitic activity of new n-alkyl derivatives of 1-(nitrophenyl)-3-(methyl-3-indolyl)-prop-2-ene-1-ones (nitroindolylchalcones)].		1996	9008902
[impact of new methodologies in the study of parasites].		1996	9011513
differentiation of entamoeba histolytica and entamoeba dispar in cyst-passers by immunoblot.	differentiation of invasive strains of entamoeba histolytica according to their pathogenicity has been a topic of long debate, but now the pathogenic species only is regarded as e. histolytica while the non pathogenic species is e. dispar. the present study applied immunoblot to differentiate infections of the two species among microscopically-detected cyst-passers in korea. the crude extract of e. histolytica separated in 5.20% gradient gels, revealed many fractions of 94, 81, 71, 50, 44, 38.5, ...	1996	9017910
does anti-parasitic treatment normalize platelets morphology in patients infested with entamoeba histolytica?	platelets are part of body defence system, especially the anti-parasite immunologic response. platelets manifest their functions only after their activation. thrombine activates platelets inducing change of their shape and causing secretion of certain substances. this study was designed to estimate platelet morphology as an indicator of their activation and effectiveness of anti-parasite therapy. the study was conducted in group of 30 patients infested with e. histolytica before treatment (a) an ...	1996	9020537
rapid postmortem invasion of cecal mucosa of macaques by nonpathogenic entamoeba chattoni.	although entamoeba histolytica is the third leading parasitic cause of death in the world, most infections in humans are asymptomatic and restricted to the intestinal lumen. entamoeba histolytica infections have also been reported in most species of captive nonhuman primates, with new world monkeys being particularly susceptible to fatal invasive amebiasis. in contrast, old world monkeys appear to be resistant to the disease, although tissue invasion in asymptomatic monkeys has been reported. ou ...	1996	9025684
seroepidemiology of entamoeba histolytica in a slum in northeastern brazil.	infection with the human pathogenic parasite entamoeba histolytica has not been well-characterized in northeastern brazil. in this study, the prevalence of e. histolytica infection in a slum in northeastern brazil was assayed using an enzyme-linked immunosorbent assay (elisa) for antibodies against the galactose/n-acetyl-d-galactosamine (gal/galnac)-inhibitable adherence lectin of e. histolytica. sera from a total of 335 individuals were examined for anti-gal/galnac lectin antibodies. the overal ...	1996	9025700
stable episomal transfection and gene expression in entamoeba dispar.		1996	9027760
pyruvate: ferredoxin oxidoreductase from entamoeba histolytica recognized by a monoclonal antibody.	a mouse monoclonal antibody, eh208c2-2 mab, raised against whole cell antigens of entamoeba histolytica trophozoites of the pathogenic strain hm-1: imss and polyclonal antisera (pab) against membrane antigens of e. histolytica trophozoites of strain hth-56: mutm were screened against a cdna library of the pathogenic strain, sfl3. the monoconal antibody detected many phage plaques expressing an e. histolytica protein. the dna sequence encoding the protein was approximately 55% identical, over 1,1 ...	1996	9031403
application of polymerase chain reaction for diagnosing amebic liver abscess.	polymerase chain reaction (pcr) has been applied in diagnosing amebic liver infection by detecting pathogenic entamoeba histolytica dna in liver aspirates. oligonucleotide primers found to be specific for the gene encoding the 30 kda molecule of this pathogenic ameba were used in the test. liver aspirates obtained from 23 patients with amebic liver abscess substantiated by typical clinical manifastation or with very high titres of anti-e histolytica antibodies by elisa were found to be positive ...	1996	9387418
[presence of various pathogenic microorganisms in fresh vegetables in costa rica].	this study reports the occurrence of some pathogenic microorganisms in vegetable consumed on a daily basis by costa ricans. cryptosporidium sp. oocysts were found in 5.2% (4/80) of cilantro leaves, in 8.7% (7/80) of cilantro roots and 2.5% of lettuce samples. a 1.2% (1/80) incidence was found in other vegetables samples (carrot, cucumber, radish and tomatoe). oocysts of this parasite were absent in cabbage. giardia intestinalis was only detected in 5.2% (4/80) of cilantro leaves and in 2.5% (2/ ...	1996	9429609
recent advances in dna-mediated gene transfer of entamoeba histolytica.	during the past few years, the introduction of dna-mediated gene transfer into parasite research has permitted subtle studies on fundamental aspects of parasite biology. in this paper, egbert tannich describes the recent breakthrough of successful entamoeba histolytica transfection, and the subsequent developments in this field.	1996	15275214
modulation of host cell intracellular ca2+.	during the course of evolution, protozoan parasites have developed strategies to subvert the immune response of their host in order to multiply, reproduce and survive. one of these inherited strategies is their capacity to modulate the host cell transductional mechanisms in their favor. alteration of host cells ca(2-) homeostasis following interaction and/or invasion by protozoan parasites such as leishmania donovani, trypanosoma cruzi, plasmodium falciparum or entamoeba histolytica has been rep ...	1996	15275223
differentiation of entamoeba histolytica and entamoeba dispar infections.	in this article, terry jackson and jonathan ravdin briefly review the latest information on monoclonal antibody-based elisas that use antigen capture as a tool in the differential detection of human infection with entamoeba histolytica and e. dispar. current technology of culture and isoenzyme analysis is not widely available, is cumbersome and too time-consuming. a further potential benefit of antigen detection tests is that they can be used to monitor the efficacy of therapy; this is a shortco ...	1996	15275293
progress towards an amebiasis vaccine.	amebiasis (infection by entamoeba histolytica) remains a major health problem in much of the developing world. morbidity and mortality from amebic dysentery and amebic liver abscess have persisted despite the availability of effective anti-amebic therapy, suggesting a need for alternative measures of disease control. through the application of recombinant dna technology, several e. histolytica antigens have now been expressed in prokaryotic systems and tested in animal models as vaccines to prev ...	1996	15275302
the invasiveness of entamoeba histolytica - a continuing enigma.		1996	16696073
association of parasites and diarrhoea among children less than five years of age in a rural area in egypt.	a case control study was conducted in kafr el-sheikh governorate, egypt, a rural community, to assess the relation of parasites and diarrhoea among children <5 years. a sample of 196 cases with diarrhoea and 83 non-diarrhoeic controls were included in the study. a questionnaire was completed for every child and weight and height were recorded. a stool sample was obtained and examined for parasites present. the results revealed that 70.3% of cases had parasites compared to 59% of controls. the mo ...	1996	17214190
[enteropathogenic agents isolated in persistent diarrhoea].	out of 45558 patients admited in our hospital, from january 1990 to december 1993, the clinical records of 4445 children with diarrhoea (4289 with acute diarrihoea and 156 with persistent diarrhoea) were reviewed. those with positive bacteriological or parasitological results were taken as sample. salmonella was the bacteria most frequently isolated in both groups of patients. ecep and eceh had a similar distribution while shigella showed a higher frequency in cases of persistent diarrhoea, for ...	1996	12165786
[amebiosis]	this is a short review of the infection and disease caused by entamoeba histolytica. the morphology of the evolutive stages and the life cycle of the parasite is described, including biochemical and immunological data.the intestinal and extraintestinal forms of this disease are briefly characterized as well as the diagnosis by images and laboratory. differentiation between e. histolytica and e. dispar (known as nonpathogenic e. histolytica) with similar morphology is crucial for individual or ma ...	1997	12297882
[parasitary infections of the liver]	in perú three are the parasites which affect frequently the liver: entamoeba histolytica, echinococcus granulosus and hepatic fasciola.amebic liver abscess can start acutely or insidiously with fever and right upper quadrant abdominal pain, with or without liver or intercostal tenderness. the main complications are thoracic, peritoneal or pericardial extension (left lobe abscess). diagnosis by images study and serology techniques are effective. currently, metronidazole is the treatment of choice ...	1997	12297885
[prevalence of intestinal parasitosis in schoolchildren].	aiming to identify the prevalence and the social risk factors of the intestinal parasitosis in first grade school children of campinas, state of são paulo, brazil.	1997	14685375
amoebapores.	the enormous cytolytic potential of entamoeba histolytica appeals to parasitologists and immunologists because it kills target cells in a contact-dependent reaction resembling that of cytotoxic lymphocytes. in this review, matthias leippe summarizes what is currently known about a family of pore-forming peptides termed 'amoebapores', to which the cytolytic effect has been attributed, and describes the structural and functional properties of these potent factors, as well as their structure-activi ...	1997	15275088
survival strategies of entamoeba histolytica: modulation of cell-mediated immune responses.	tissue invasion and disease associated with the protozoan entamoeba histolytica has long been connected with suppression of host cellular immunity. dampening of the host's defences may facilitate survival of amoebae in extraintestinal sites and development of the characteristic amoebic abscesses. in recent years, several studies have begun to clarify, at the cellular level, the specific effects e. histolytica has on immune cell accessory and effector cell functions. here, darren campbell and kri ...	1997	15275089
the role of extracellular cysteine proteinases in pathogenesis of entamoeba histolytica invasion.	the extracellular cysteine proteinases of entamoeba histolytica have been implicated as important virulence factors in the pathogenesis of amebiasis and play a key role in tissue invasion and disruption of host defenses. these proteinases have attracted considerable interest as targets for novel therapeutic agents and as vaccine candidates. here, xuchu que and sharon reed highlight some of the more recent findings, focusing in particular on functional and structural features of the extracellular ...	1997	15275090
short report: identification of b-cell epitopes in the serine-rich entamoeba histolytica protein.	the serine-rich entamoeba histolytica protein (srehp) has been shown to be a protective antigen in animal models of amebic liver abscess when delivered by either parenteral or oral routes of immunization, and antibodies to srehp can prevent amebic liver abscess in severe combined immunodeficient mice. to identify b cell epitopes of the srehp molecule that could serve as the basis for a peptide-based vaccine, we synthesized overlapping peptides spanning the amino acid sequence of srehp, and looke ...	1997	9430535
present characteristics of symptomatic amebiasis due to entamoeba histolytica in the east-southeast area of tokyo.	admitted medical records, from january 1988 to december 1995, of 28 symptomatic amebic patients who lived in the east-southeast area of tokyo were studied retrospectively, in order to find the present characteristics of symptomatic amebiasis due to entamoeba histolytica in this area. categorized by disease, there were 14 cases of colitis, 9 cases of liver abscess, 4 cases of colitis with liver abscess, and 1 case of liver abscess with brain abscess. patients consisted of 26 japanese males, 0 jap ...	1997	9440441
molecular methods for diagnosis and epidemiological studies of parasitic infections.	direct microscopy is widely used for the diagnosis of parasitic infections although it often requires an experienced microscopist for accurate diagnosis, is labour intensive and not very sensitive. in order to overcome some of these shortcomings, molecular or nucleic acid-based diagnostic methods for parasitic infections have been developed over the past 12 years. the parasites which have been studied with these techniques include the human plasmodia, leishmania, the trypanosomes, toxoplasma gon ...	1997	9394184
virulence parameters in the characterization of strains of entamoeba histolytica.	differences in virulence of strains of entamoeba histolytica have long been detected by various experimental assays, both in vivo and in vitro. discrepancies in the strains characterization have been arisen when different biological assays are compared. in order to evaluate different parameters of virulence in the strains characterization, five strains of e. histolytica, kept under axenic culture, were characterized in respect to their, capability to induce hamster liver abscess, erythrophagocyt ...	1997	9394517
effect of intestinal parasite treatment on the efficacy of oral iodized oil for correcting iodine deficiency in schoolchildren.	oral supplementation with iodized oil for correction of iodine deficiency in a population has advantages over intramuscular injection but the duration of effect is shorter. the relation of intestinal parasite treatment and efficacy of oral iodized oil was examined in an intervention study in 8-10-y-old schoolchildren in malawi. severely iodine-deficient schoolchildren with a single parasitic infestation of ascaris lumbricoides (n = 44), hookworm (n = 42), or entamoeba histolytica (n = 24) were r ...	1997	9394695
fibronectin-derived fragments as inducers of adhesion and chemotaxis of entamoeba histolytica trophozoites.	active migration of entamoeba histolytica trophozoites through extracellular matrixes might play a role in host tissue destruction. trophozoites degrade soluble fibronectin (fn) bound to their surface and adhere to substrate-bound fn, producing local degradation. fn proteolytic fragments were used to determine the nature of adhesion and motility-promoting domains within the protein. the 70-kda fragment (amino-terminal end) promoted the highest adhesion, followed by the 120-kda fragment, which co ...	1997	9395373
epidemiological study on infectious diarrheal diseases in children in a coastal rural area of kenya.	diarrheal diseases are major causes of morbidity and mortality among children in developing countries. we have analyzed the causative agents of diarrhea in children under five years of age who resided in rural environments but attended a hospital in malindi, a coastal town in kenya. bacterial diarrhea was found in 239 (27.7%) of 862 patients with diarrhea. diarrheagenic escherichia coli, including enteropathogenic, enterotoxigenic, and enterohaemorrhagic strains, was isolated from 119 (13.8%) pa ...	1997	9403500
amebiasis in schistosomiasis endemic and non-endemic areas in egypt.	stool and blood specimens were collected from each of 404 and 576 individuals at sindbis village (qualiubia governorate) in the nile delta where schistosomiasis is endemic and el-rashda village (new valley governorate) in the western desert of egypt where there is no schistosomiasis; respectively. based on the microscopical examination of stool specimens, the prevalence of infection with entamoeba (e. histolytica and/or e. dispar which are morphologically indistinguishable) was higher at sindbis ...	1997	9425808
blastocystis hominis among apparently healthy food handlers in jeddah, saudi arabia.	a prospective study was carried out to investigate the prevalence of blastocystis hominis among random sample of apparently healthy food handlers. a total of 250 non saudi males over 21 years of age were examined. ninety (36%) had pathogenic and non pathogenic intestinal parasites. a total of 143 parasites were detected in their stool specimens. twenty were b. hominis (13.99%) while other parasites were 123 (86.01%). b. hominis was found in 20 positive cases (22.22%) with an overall rate of 8%. ...	1997	9425825
characterization for virulence of an axenic strain of entamoeba histolytica: evidence for overexpression of two proteins.	the pattern of protein from membrane and crude homogenate of entamoeba histolytica strain 462 axenically cultivated (462ac) and submitted to hamster liver passage (462hp) was obtained by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. the substrains 462ac and 462hp were compared by zymodeme analysis, erythrophagocytosis, cytopathic effect upon mammalian cells and the capability to induce abscess in hamster liver. the results showed no differences for erythrophagocytosis, cytopathic ef ...	1997	9428571
[the diagnosis and surgical treatment of intestinal amebiasis].	ninety-one patients with intestinal amebiasis (ia) were studied. all had been long suffering from ia due to the fact that it had not been diagnosed in time. indications for emergency surgery were profuse hemorrhage, perforation of amebic ulcers, gangrene, and toxic dilatation of the large intestine. planned operations were made in pseudopolyposis, strictures of the large intestine. surgical treatment was performed along with specific therapy. seven patients died due to late diagnosis, ineffectiv ...	1997	9446003
pyogenic liver abscess in children: some observations in the espírito santo state, brazil.	pyogenic liver abscess in children is uncommon in developed countries and there are few reports about the disease in developing countries including brazil. as pyogenic liver abscesses in children are frequently diagnosed in vitória (e. santo state, brazil), the records of admissions at the children's hospital (hospital infantil n.s. da glória) were surveyed. sixty-five cases of pyogenic liver abscess were observed over a period of three years, from may 1991 through april 1994 (mean of admissions ...	1997	9458960
involvement of superoxide dismutase and pyruvate:ferredoxin oxidoreductase in mechanisms of metronidazole resistance in entamoeba histolytica.	metronidazole resistance has been induced in an axenic strain of entamoeba histolytica (hth-56:mutm) following continuous exposure to steadily increasing drug concentrations. the drug-resistant line is routinely maintained in normally lethal levels of metronidazole (10 microm). resistance to this concentration of drug was developed over 177 days. decreased pyruvate:ferredoxin oxidoreductase (pfor) activity in anaerobic organisms is one mechanism of metronidazole resistance but in entamoeba, pfor ...	1997	9462435
heterogeneity of dna content and expression of cell cycle genes in axenically growing entamoeba histolytica hm1:imss clone a.	the cell division cycle of entamoeba histolytica was studied using multi-parametric flow cytometry in asynchronous and partially synchronised cells. dynamic changes in the dna synthesis and dna content of axenically growing trophozoites were observed by using 5-bromo-2'-deoxyuridine (brdu) uptake and dna specific fluorochromes. it was observed that dna synthesis in these cells continues beyond the typical s-phase stop point when dna duplication is complete. asynchronously growing e. histolytica ...	1997	9497028
molecular and biochemical characterization of phosphoglucomutases from entamoeba histolytica and entamoeba dispar.	entamoeba histolytica and entamoeba dispar have only recently been defined as two separate species. e. histolytica, the pathogenic species, is the microorganism causing invasive intestinal amoebiasis and/or liver abscess, while the morphologically similar e. dispar is nonpathogenic and noninvasive. the gold standard for the distinction of the two species has been the isoenzyme electrophoresis of phosphoglucomutases (ec 5.4.2.2) and hexokinases (ec 2.7.1.1), but there had also been a controversy ...	1997	9497037
primary structure of entamoeba histolytica gamma-tubulin and localisation of amoebic microtubule organising centres.		1997	9497056
[infection by intestinal protozoa and helminths in schoolchildren from riverside sectors, with different fecal contamination levels, of valdivia river, chile].	during 1993, the prevalences of infection by intestinal protozoa and helminths (iph) in the riverside schoolchildren population of two sectors of valdivia river, with different levels of fecal contamination, were compared in relation to their contact with river water (swimming, bathing) and basic sanitation elements (bse) of their houses: feces and garbage disposal, and water supply. populations of children from sectors a (n = 418), with significatively greater (sg) total coliform most probable ...	1997	9497533
[human infection by intestinal protozoa and helminths in calbuco county, x region, chile, 1997].	by the performance of parasitological examination of one fecal sample per individual, a total of 256 persons from a rural county in the x region (41 degrees 50 minutes south lat., 73 degrees 05 minutes west long.) were studied. the general rates of infection by intestinal parasite and/or commensal protozoa and helminths found were: giardia intestinalis 14.1%, entamoeba histolytica 11.7%, blastocystis hominis 36.0%, entamoeba coli 9.8%, endolimax nana 16.4%, iodamoeba buetschlii 1.2%, chilomastix ...	1997	9497539
glycosidases in mucin-dwelling protozoans.	a range of protozoans were tested for the presence of glycosidases using p-nitrophenyl sugars as substrates. some of the organisms were mucin dwellers whereas others were blood borne parasites. it had been hypothesized that glycosidase production would be significantly higher in the mucin dwellers. the results obtained demonstrated that the urogenital protozoans tritrichomonas foetus and trichomonas vaginalis produced a vast range of glycosidases which included those required for mucin breakdown ...	1997	9511996
[an amebic liver abscess; early suspicion, late detection].	two men aged 38 and 26 years developed symptoms including pain in the (upper) abdomen, malaise and fever 1.5-5 months after visiting the caribbean. it was only after repeated ultrasonography that liver abscesses were observed. adequate treatment was instituted and the patients recovered. the diagnosis of 'amoebic abscess of the liver' is usually based on the clinical presentation, the serological findings and characteristic observations at ultrasonography. however, if patients are seen at an ear ...	1997	9542869
[enteroparasitoses in food handlers of the public schools in uberlândia (minas gerais), brazil].	a prospective study based on a parasitologic survey was carried out with a view toward controlling enteroparasitoses in food handlers who work in public primary schools in uberlândia, minas gerais, brazil. the study subjects were 264 individuals from 57 schools, from whom three fecal samples (c) were collected: c1 in september 1989, c2 in april 1990, and c3 in september 1990. the participants were predominantly female (259 women and 5 men) and ranged in age from 20 to 66 years. a total of 792 sa ...	1997	9546081
nitazoxanide for the treatment of intestinal protozoan and helminthic infections in mexico.	a study to evaluate the efficacy and safety of nitazoxanide as a single agent for the treatment of a broad spectrum of mixed parasitic infections, both protozoa and helminths, was conducted at a primary school in san pedro tolimán, querétaro, mexico. three faecal samples from 1824 adults and children were screened for the presence of oocysts, cysts, trophozoites, eggs or larvae of intestinal protozoa or helminths. two hundred and forty-six adults and children infected with at least one protozoan ...	1997	9580117
the bactericidal activity of blood platelets in patients infested with entamoeba histolytica/entamoeba dispar.	blood platelets participate actively in organism defensive reactions and particularity in antiparasitic immunity. platelets stimulation can be the result of contact with a parasite, the presence of immunoglobulins, complement and lymphokines. the aim of the study was to evaluate the blood platelets bactericidal activity in the course of amoebiasis. the examination was carried out in the group of 22 patients with e. histolytica/e. dispar, diagnosed on the basis of cyst forms presence in faeces. t ...	1997	9581473
characterization and quantitation of parasite species in the effluents of the berisso main sewage channel, buenos aires, argentina.	outbreaks of disease can be caused by pathogenic intestinal parasites in drinking water. la plata, the capital of the province of buenos aires, argentina, is located on the la plata river; a principal tributary receiving the raw sewage from the city's 500,000 inhabitants via the berisso main septic channel at an estimated volume of 108,390 m3/day (4516.3m3/h). to determine the parasite-contamination level of the la plata river, we obtained 18 sewage effluents from the berisso main septic channel ...	1997	9638888
[vegetables for human consumption as probable source of toxocara sp. infection in man].	although toxocara canis life cycle is known, other possible mechanisms dynamically involved in its transmission to man are still ignored. the object of the present investigation was to search the occurrence of toxocara sp. eggs in vegetables which humans consume. five hundred and thirty six vegetables from a supply distribution center in mexico city (distrito federal) were examined. those included 212 carrots, 76 potatoes, 31 radishes, 22 mushrooms, 27 lettuces, 20 sweet potatoes and 66 bundles ...	1997	9640678