Publications

TitleAbstractYear(sorted ascending)
Filter
PMID
Filter
how to diagnose and manage common parasitic pneumonias.parasitic pneumonia is being increasingly reported from many parts of the world due to globalization and travel across the continents. this review outlines the recent developments in the diagnosis and management of parasitic pneumonias.200717414130
transcriptional upregulation of genes related to virulence activation in entamoeba histolytica.to understand the molecular basis of virulence variability in entamoeba histolytica, this study presents results about differential gene expression induced by e. histolytica trophozoites in liver of hamsters in order to produce experimental amebic liver abscess (ala) and consequently reactivate its virulence.200717416282
enteroparasitic occurrence in stools from residents in southwestern region of saudi arabia before and during umrah season.study of the prevalence of human gastro-intestinal parasitic infections among patients living in makkah al-mukkarmah city before and during umrah season.200717334465
entamoeba histolytica: apoptosis induced in vitro by nitric oxide species.apoptosis has been described in some parasites like leishmania, trypanosoma, and trichomonas. this phenomenon has not been observed yet in entamoeba histolytica. this work analyzed the in vitro effect of sodium nitroprusside, sodium nitrite and sodium nitrate (nos) on e. histolytica apoptosis. parasites incubated for 1h with nos revealed apoptosis 6h later (95% viability), demonstrated by yopro-1, tunel, dna fragmentation and low atp levels. the caspase inhibitor z-vad-fmk inhibited total intrac ...200717336295
nitric oxide production and nitric oxide synthase immunoreactivity in naegleria fowleri.free-living ameba naegleria fowleri produces an acute and fatal infectious disease called primary amebic meningoencephalitis (pam), whose pathophysiological mechanism is largely unknown. the aim of this study was to investigate the role of nitric oxide (no) in pam. although no has a cytotoxic effect on various parasites, it is produced by others as part of the pathology, as is the case with entamoeba histolytica. to test for the production of no, we analyzed whether antibodies against mammalian ...200717340143
magnesium promotes structural integrity and conformational switching action of a calcium sensor protein.calcium binding proteins carry out various signal transduction processes upon binding to ca2+. in general, these proteins perform their functions in a high background of mg2+. here, we report the role of mg2+ on a calcium sensor protein from entamoeba histolytica (ehcabp), containing four ca2+-binding sites. mg2+-bound ehcabp exists as a monomer with a conformation different from that of the holo- and apo-ehcabp. nmr and biophysical data on ehcabp demonstrate that mg2+ stabilizes the closed conf ...200717315953
importance of the detection of amoebic antigens in stool samples for the diagnosis of entamoeba histolytica infection, among children in southern turkey.entamoeba histolytica is the predominant causative agent of human amoebiasis, a significant and common diarrhoeal disease among children of developing countries. diagnosis of this illness by the microscopical detection of the parasites in stool samples is insensitive and often incapable of differentiating the pathogenic entamoeba histolytica from the commensal parasite e. dispar. in this study, the results of testing stool samples in an elisa, based on a monoclonal antibody, that detects e. hist ...200717316500
differentiation of entamoeba histolytica and entamoeba dispar by pcr: a preliminary study in izmir, turkey.the causative agent of amoebiasis is currently attributed to two distinct species (e. histolytica and e. dispar). the aim of this study was to differentiate these species by pcr in stool samples. isolated genomic dna was amplified by pcr and band products of 101 bp (e. dispar) were obtained. all seven stool samples were found to be e. dispar, not e. histolytica. our results demonstrated the significance of e. histolytica/dispar differentiation in the diagnosis of amoebiasis. this study is prelim ...200717319599
ehgef3, a novel dbl family member, regulates ehraca activation during chemotaxis and capping in entamoeba histolytica.rho gtpases are critical elements involved in the regulation of signal transduction cascades from extracellular stimuli to cytoskeleton. the rho guanine nucleotide exchange factors (rhogefs) have been implicated in direct activation of these gtpases. here, we describe a novel rhogef, denominated ehgef3 from the parasite entamoeba histolytica, which encodes a 110 kda protein containing the domain arrangement of a dbl homology domain in tandem with a pleckstrin homology domain, the dh domain of eh ...200717323375
stable expression of gal/galnac lectin of entamoeba histolytica in transgenic chloroplasts and immunogenicity in mice towards vaccine development for amoebiasis.chloroplast genetic engineering offers several advantages, including high levels of transgene expression, transgene containment via maternal inheritance and multigene engineering in a single transformation event. entamoeba histolytica infects 50 million people, causing about 100,000 deaths annually, but there is no approved vaccine against this pathogen. leca, a potential target for blocking amoebiasis, was expressed for the first time in transgenic plants. stable transgene integration into chlo ...200717309678
induction of monocyte chemotactic protein 1 in colonic epithelial cells by entamoeba histolytica is mediated via the phosphatidylinositol 3-kinase/p65 pathway.the role intestinal epithelial cells play in the pathogenesis of amebic colitis is poorly understood. herein, we demonstrate that secreted and soluble ameba (entamoeba histolytica) proteins (sap) induce expression of the chemoattractant monocyte chemotactic protein (mcp) in the colonic epithelial cell lines caco-2, t84, and ls174t. mcp-1 mrna induction was both dose and time dependent, with peak induction occurring at 8 h and with 100 mug/ml of sap. significant increase in mcp-1 protein expressi ...200717283105
correlation of interferon-gamma production by peripheral blood mononuclear cells with childhood malnutrition and susceptibility to amebiasis.the contribution of interferon-gamma (ifn-gamma) to immunity from amebiasis was assessed in a three-year prospective study of children 2-5 years of age in an urban slum of dhaka, bangladesh. ifn-gamma produced by peripheral blood mononuclear cells stimulated with soluble amebic antigen was measured upon enrollment. thirty-one of the 209 enrolled children had entamoeba histolytica-associated diarrhea. children who produced higher than the median level of ifn-gamma (median = 580 pg/ml) had longer ...200717297046
onchocerca volvulus-specific antibody and cytokine responses in onchocerciasis patients after 16 years of repeated ivermectin therapy.the recommended control option against onchocerciasis is repeated ivermectin treatment, which will need to be implemented for decades, and it remains unknown how repeated ivermectin therapy might affect immunity against onchocerca volvulus in the long term. o. volvulus-specific antibody reactivity and cellular cytokine production were investigated in onchocerciasis patients receiving ivermectin (150 microg/kg) annually for 16 years. in treated patients, the t helper type 2 (th2) cytokine interle ...200717302900
the 29-kilodalton thiol-dependent peroxidase of entamoeba histolytica is a factor involved in pathogenesis and survival of the parasite during oxidative stress.the 29-kda surface antigen (thiol-dependent peroxidase; eh29) of entamoeba histolytica exhibits peroxidative and protective antioxidant activities. during tissue invasion, the trophozoites are exposed to oxidative stress and need to deal with highly toxic reactive oxygen species (ros). in this investigation, attempts have been made to understand the role of the 29-kda peroxidase gene in parasite survival and pathogenesis. inhibition of eh29 gene expression by antisense rna technology has shown a ...200717307964
growth of the protozoan parasite entamoeba histolytica in 5-azacytidine has limited effects on parasite gene expression.in higher eukaryotes dna methylation regulates important biological functions including silencing of gene expression and protection from adverse effects of retrotransposons. in the protozoan parasite entamoeba histolytica, a dna methyltransferase has been identified and treatment with 5-azacytidine (5-azac), a potent inhibitor of dna methyltransferase, has been reported to attenuate parasite virulence. however, the overall extent of dna methylation and its subsequent effects on global gene expre ...200717207281
colonic amoebiasis and spirochetosis: morphological, ultrastructural and microbiological evaluation.the present study reports on a prompt diagnosis of colonic amoebiasis with colonic spirochetosis by brachyspira aalborgi and b. pilosicoli; such diagnosis allowed exclusion of other diseases and resolution of the case after specific treatment.200717201883
activation of dendritic cells by the gal-lectin of entamoeba histolytica drives th1 responses in vitro and in vivo.amebiasis is a human disease caused by the protozoan intestinal parasite entamoeba histolytica. vaccine development has focused on the parasite's surface galactose-n-acetyl-d-galactosamine inhibitable lectin (gal-lectin) as a protective antigen. the gal-lectin is immunogenic and has been shown to induce th1 cytokines in vitro and in vivo. the immunological basis of the protective immune response elicited by the gal-lectin is unknown. in this study, we investigated the response of balb/c bone mar ...200717219364
current therapeutics, their problems, and sulfur-containing-amino-acid metabolism as a novel target against infections by "amitochondriate" protozoan parasites.the "amitochondriate" protozoan parasites of humans entamoeba histolytica, giardia intestinalis, and trichomonas vaginalis share many biochemical features, e.g., energy and amino acid metabolism, a spectrum of drugs for their treatment, and the occurrence of drug resistance. these parasites possess metabolic pathways that are divergent from those of their mammalian hosts and are often considered to be good targets for drug development. sulfur-containing-amino-acid metabolism represents one such ...200717223627
pcr detection of entamoeba histolytica, entamoeba dispar, and entamoeba moshkovskii in stool samples from sydney, australia.this study investigated the presence of entamoeba histolytica, entamoeba dispar, and entamoeba moshkovskii in stool samples from a patient population in sydney, australia. stool samples were tested by microscopy and pcr. five patients were found with e. histolytica infections, while e. dispar and e. moshkovskii were observed in 63 (70.8%) and 55 (61.8%) patients, respectively, by pcr. this is the first study in australia using molecular techniques to determine the presence of e. histolytica, e. ...200717229864
fulminant amoebic colitis following loperamide use.toxic megacolon is a rare consequence of infection with entamoeba histolytica. we present such a patient in whom the course of disease may have been influenced by heavy loperamide use. loperamide and other anti-motility agents have been implicated previously in the pathogenesis of toxic megacolon in patients with infectious gastroenteritis.200717241255
identification of developmentally regulated genes in entamoeba histolytica: insights into mechanisms of stage conversion in a protozoan parasite.developmental switching between life-cycle stages is a common feature among many pathogenic organisms. the protozoan parasite entamoeba histolytica converts between cysts (essential for disease transmission) and trophozoites (responsible for tissue invasion). identification of genes involved in the developmental pathway has been severely hindered by the inability to generate e. histolytica cysts in vitro. using parasite strains derived from recent human infections and whole-genome transcriptiona ...200717250591
luminal host-defense mechanisms against invasive amebiasis.most humans infected with the virulent protozoan parasite entamoeba histolytica do not develop invasive disease. available evidence indicates that beneficial bacteria and the mucus gel layer in the colon lumen protect the host mucosa. glycosidases produced by some normal colonic bacteria and luminal proteases degrade the key adherence lectin on e. histolytica trophozoites and decrease their adherence to epithelial cells. the mucus gel layer prevents those trophozoites that escape the hydrolases ...200717258936
syntheses, characterization and in vitro antiamoebic activity of new pd(ii) complexes with 1-n-substituted thiocarbamoyl-3,5-diphenyl-2-pyrazoline derivatives.reaction of neutral ns bidentate ligands, 1-n-substituted thiocarbamoyl-3,5-diphenyl-2-pyrazolines, isolated by cyclization of chalcone with n-4-substituted thiosemicarbazide of aromatic amines (1-8), with [pd(dmso)(2)cl(2)] (dmso=dimethylsulfoxide) leads to the formation of new complexes of the type [pd(l)cl(2)] (1a-8a). the structures of the compounds were elucidated by uv, ir, (1)h nmr, (13)c nmr and esi-ms spectral data and thermogravimetric analysis and their purities were confirmed by elem ...200717156895
antiparasitic drug nitazoxanide inhibits the pyruvate oxidoreductases of helicobacter pylori, selected anaerobic bacteria and parasites, and campylobacter jejuni.nitazoxanide (ntz) exhibits broad-spectrum activity against anaerobic bacteria and parasites and the ulcer-causing pathogen helicobacter pylori. here we show that ntz is a noncompetitive inhibitor (k(i), 2 to 10 microm) of the pyruvate:ferredoxin/flavodoxin oxidoreductases (pfors) of trichomonas vaginalis, entamoeba histolytica, giardia intestinalis, clostridium difficile, clostridium perfringens, h. pylori, and campylobacter jejuni and is weakly active against the pyruvate dehydrogenase of esch ...200717158936
transcriptomic comparison of two entamoeba histolytica strains with defined virulence phenotypes identifies new virulence factor candidates and key differences in the expression patterns of cysteine proteases, lectin light chains, and calmodulin.the availability of rahman, and the virulent hm-1:imss strain of e. histolytica, provides a powerful tool for identifying virulence factors of e. histolytica. here we report an attempt to identify potential virulence factors of e. histolytica by comparing the transcriptome of e. histolytica hm-1:imss and e. histolytica rahman. with phenotypically defined strains, we compared the transcriptome of rahman and hm-1:imss using a custom 70mer oligonucleotide based microarray that has essentially full ...200717141337
isolation of pure compound r/j/3 from pluchea indica (l.) less. and its anti-amoebic activities against entamoeba histolytica.the plant pluchea indica is known for its anti-inflammatory, anti-ulcer, anti-pyretic, hypoglycemic, diuretic and anti-microbial activities besides many other pharmacological activities. we have isolated and purified seven compounds from the methanolic root extract of this plant by column chromatography. the compounds were identified by spectroscopic analyses. the anti-amoebic activities of the pure compound r/j/3 was investigated against the hm1 strain of entamoeba histolytica. the compound, r/ ...200717174538
sine elements of entamoeba dispar.entamoeba histolytica and e. dispar are closely related protozoan parasites; the former causes clinical amoebiasis in humans while the latter appears to be non-pathogenic. the molecular biology of e. histolytica shows a number of unusual features, one of which is the abundance of polyadenylated but apparently untranslatable mrnas produced; many of these are the product of at least three families of sines (ehsine1-3). here we show that the genome of e. dispar contains numerous copies of a sine el ...200717178164
incidence of cyclosporiasis in patients with gastrointestinal symptoms in western turkey.this study was designed to investigate the distribution of cyclosporiasis between october 2003 and october 2004 and the relationship between cyclospora infection and seasonal as well as patient factors in western turkey.200717179908
innate resistance to entamoeba histolytica in murine models.hamano et al. have recently reported that in murine models of amebiasis, innate resistance is associated with nonhemopoietic cells and depends on the activity of interleukin-10. this article raises the issue of the importance of predisposition to amebic colitis and discusses which host factors have a role in innate resistance to invasive disease. resistance studies that elucidate the mechanisms involved in parasite clearance or parasite invasion are essential to understanding the incidence of am ...200717185037
initiation of inflammation and cell death during liver abscess formation by entamoeba histolytica depends on activity of the galactose/n-acetyl-d-galactosamine lectin.the parasite entamoeba histolytica colonizes the human intestine causing amoebic colitis and disseminates through the vascular route to form liver abscesses. the gal/galnac lectin is an adhesion protein complex which sustains tissue invasion by e. histolytica. disruption of the gal/galnac lectin function in engineered parasites (hgl-2 trophozoites) changed the pathophysiology of hamster liver abscess formation. hgl-2 trophozoites produced numerous small inflammatory foci located in the vicinity ...200717188278
molecular methods for diagnosis of entamoeba histolytica in a clinical setting: an overview.the range of clinical outcomes following entamoeba histolytica infection is likely to be influenced by the different strains of the parasite already existing in our population. there is a need for developing faster, reliable and reproducible methods for identifying the different strains of e. histolytica. this would have a major impact on the subsequent course of treatment given to patients. in the post-genomic era, different loci of the entamoeba genome have been targeted for developing suitabl ...200717189632
identification of putative transcriptional regulatory networks in entamoeba histolytica using bayesian inference.few transcriptional regulatory networks have been described in non-model organisms. in entamoeba histolytica seminal aspects of pathogenesis are transcriptionally controlled, however, little is known about transcriptional regulatory networks that effect gene expression in this parasite. we used expression data from two microarray experiments, cis-regulatory motif elucidation, and a naïve bayesian classifier to identify genome-wide transcriptional regulatory patterns in e. histolytica. our algori ...200717355990
comparison of entamoeba histolytica dna isolated from a cynomolgus monkey with human isolates.three protein-coding loci in dna of an entamoeba histolytica strain (ehmfas1) isolated from cynomolgus monkey (macaca fascicularis) were sequenced; these loci corresponded to the genes for chitinase, the serine-rich e. histolytica protein (srehp), and the 16 s-like small subunit ribosomal rna (16s-like ssurrna). the nucleotide and deduced amino-acid sequences of chitinase and srehp were compared with sequences from human isolates. ehmfas1 had several specific mutations in units in the polymorphi ...200717356893
drug targets from human pathogenic amoebas: entamoeba histolytica, acanthamoeba polyphaga and naegleria fowleri.in this review we present our search for the presence of drug targets in several species of human pathogenic parasites, mainly the amoebas entamoeba histolytica, acanthamoeba polyphaga and naegleria fowleri. we started with an analysis of the concepts of essentiality and validity of the targets and continue with a description of the main characteristics of pathogenicity of these amoebas. we then proceed to evaluate these targets arranged mainly in seven groups corresponding to: a) enzymes which ...200717897063
involvement of beta 2-integrin in ros-mediated neutrophil apoptosis induced by entamoeba histolytica.cellular adhesion through beta 2-integrin (cd18) is an important step in signal transduction leading to apoptosis of human neutrophils, and nadph oxidase-derived reactive oxygen species (ros) are essential for neutrophil apoptosis induced by entamoeba histolytica. therefore, we investigated the role of beta 2-integrin-mediated signals in ros-dependent neutrophil apoptosis induced by e. histolytica. entamoeba-induced apoptosis was inhibited by pre-incubation of cells with mab to cd18, but not cd2 ...200717900957
structural and functional analysis of the entamoeba histolytica ehrabb gene promoter.the entamoeba histolytica ehrabb gene encodes for a rab gtpase involved in phagocytosis. it is located at a virulence locus where the ehcp112 gene is in the complementary strand at 332 bp of ehrabb start codon, suggesting a finely regulated transcription of both genes. however, the transcription regulation in this parasite is poorly understood.200717883848
caenorhabditis elegans pgp-5 is involved in resistance to bacterial infection and heavy metal and its regulation requires tir-1 and a p38 map kinase cascade.animals and plants respond to bacterial infections and environmental stresses by inducing overlapping repertoires of defense genes. how the signals associated with infection and abiotic stresses are differentially integrated within a whole organism remains to be fully addressed. we show that the transcription of a caenorhabditis elegans abc transporter, pgp-5 is induced by both bacterial infection and heavy metal stress, but the magnitude and tissue distribution of its expression differs, depend ...200717888400
invasive amebiasis: an update on diagnosis and management.in its invasive form, the trophozoite is responsible for clinical syndromes, ranging from classical dysentery to extraintestinal disease with emphasis on hepatic amebiasis. abdominal pain, tenderness and diarrhea of watery stool, sometimes with blood, are the predominant symptoms of amebic colitis. besides the microscopic identification of entamoeba histolytica, diagnosis should be based on the detection of specific antigens in the stool or pcr associated with the occult blood in the stool. ameb ...200717914922
[the evaluation of the techniques used for diagnosis of entamoeba histolytica in stool specimens].in this study, stool samples of 9378 patients from different clinics, who presented at the laboratory of the department of parasitology of the dokuz eylul university, faculty of medicine with several gastrointestinal complaints from january 2004 to may 2006, were examined. all stool samples were examined with the saline-lugol method and, in suspicious cases, by trichrome staining, cultivation in robinson's medium and/or antigen detection in stool with the entamoeba celisa path kit. forty-one cas ...200717918056
[a retrospective analysis of the results of a seven-year parasitological examination of stools from malatya state hospital].the aim of this study was to determine the prevalence of intestinal parasites and to evaluate changes in the annual rates by retrospective screening of the data from our hospital's parasitology laboratory between the period of 2000 and 2006. parasitological examinations were done with native-lugol, cellophane-tape methods and trichrome staining in ambiguous cases, in a total of 67539 samples. the prevalence of the intestinal parasitosis during the years 2000 and 2006 years were found to be 7.2% ...200717918059
profiles of a pathogenic entamoeba histolytica-like variant with variations in the nucleotide sequence of the small subunit ribosomal rna isolated from a primate (de brazza's guenon).a pathogenic entamoeba histolytica-like variant (jsk2004) with genetic variations and a novel isoenzyme pattern was isolated from a de brazza's guenon. a homology of 99.1% was found between the clones of e. histolytica (hm-1:imss) and jsk2004 in the 1,893 nucleotide bases of the small subunit rrna (ssu-rrna) gene. the dna of the pathogenic amoeba species was also extracted from two sterile liver abscesses during the autopsies of an abyssinian colobus and a geoffroy's spider monkey occurring in t ...200717939358
anti-amebic antibody activity in patients, determined with antigens prepared from virulent parasites (indirect hemagglutination assay and enzyme-linked immunosorbent assay).the serology of amebiasis is affected by low sensitivity and specificity.200717939629
[infectious aetiologies of travelers' diarrhoea].traveler's diarrhoea (td) occurs in 20 to 60% of european or north-american travelers in intertropical areas. following return from endemic zone, malaria must always be evocated in front of febrile diarrhoea. many causative infectious agents are involved in td and their frequency may vary according to destination and seasons. the main agents involved in td are escherichia coli pathovars (especially enterotoxigenic and enteroaggregative e. coli) followed by enteroinvasive bacteria (campylobacter ...200717942257
invasive amebiasis and ameboma formation presenting as a rectal mass: an uncommon case of malignant masquerade at a western medical center.a 54-year-old man presented with rectal pain and bleeding secondary to ulcerated, necrotic rectal and cecal masses that resembled colorectal carcinoma upon colonoscopy. these masses were later determined to be benign amebomas caused by invasive entamoeba histolytica, which regressed completely with medical therapy. in western countries, the occurrence of invasive protozoan infection with formation of amebomas is very rare and can mistakenly masquerade as a neoplasm. not surprisingly, there have ...200717948943
epidemiology and aetiology of diarrhoeal diseases in adults engaged in wastewater-fed agriculture and aquaculture in hanoi, vietnam.to determine the occurrence of and risk factors for diarrhoea in an adult population exposed to wastewater used for agricultural and aquacultural productions.200718005312
seroprevalence of entamoeba histolytica infection in hiv-infected patients in china.seroprevalence of entamoeba histolytica infection in hiv-infected individuals from shanghai city, anhui province, and henan province, china, was examined by enzyme-linked immunosorbent assay using crude antigen and a recombinant surface antigen, c-igl, of the parasite. in 215 hiv-infected individuals, the positive rates for these antigens were 12.1% and 7.9%, respectively; these rates were significantly higher than the rates of 3.1% and 0.5%, respectively, in 191 patients with gastrointestinal s ...200717984335
amebiasis presenting as acute appendicitis.amebiasis presenting as acute appendicitis is extremely rare. the case of a 38-year-old hispanic man who presented to the hospital with symptoms and signs suggestive of acute appendicitis is reported. he underwent laparoscopic appendectomy and the pathologic examination of the appendix revealed multiple trophozoites of entamoeba histolytica. the patient was treated postoperatively with metronidazole for amebiasis, and follow-up stool studies showed no sign of residual infection. the patient has ...200717984748
intestinal parasitic infection among children and neonatus admitted to ibn-sina hospital, sirt, libya.a total of 350 stool samples from 196 males and 154 female children and neonatus admitted in ibn-sina hospital, sirt, were examined from june 2001 to may 2002, to determine the prevalence of intestinal parasites. intestinal parasitic infections were identified in 196 (56%) of children and neonates. no intestinal helminthic parasites were detected but 13 intestinal protozoan parasites were detected. the most prevalent protozoan was entamoeba histolytica /e. dispar (36.57%); blastocystis hominis ( ...200717985574
development of a pharmacodynamic screening model with entamoeba histolytica.human amoebiasis caused by entamoeba histolytica is widely distributed in the tropics and subtropics, but also occurring in neighbouring parts of the temperate zones. invasive amoebiasis causes dysentery and, by haematogenous spread, also extra-intestinal hepatic, pulmonary or cerebral abscesses, not rarely fatal conditions. the available anti-amoebic drugs have shortcomings regarding tolerability and efficacy. to facilitate the screening of candidate material, an in vitro system has been develo ...200717987365
amebic colitis: new insights into pathogenesis and treatment.amebiasis, caused by the protozoan parasite entamoeba histolytica, affects more than 50 million people worldwide, with over 100,000 deaths annually. the majority of cases are asymptomatic; however, significant morbidity and mortality are associated with illness in the remaining 10% of cases. recent advances in the understanding of the mechanism of infection by e. histolytica, the role of the innate immune system, and the role of genetic disposition to infection will allow the development of nove ...200717991346
effect of vitamin a and zinc supplementation on gastrointestinal parasitic infections among mexican children.gastrointestinal parasites continue to be an important cause of morbidity and stunting among children in developing countries. we evaluated the effect of vitamin a and zinc supplementation on infections by giardia lamblia, ascaris lumbricoides, and entamoeba histolytica.200717908741
a mitosome purification protocol based on percoll density gradients and its use in validating the mitosomal nature of entamoeba histolytica mitochondrial hsp70.mitochondria are indispensable for aerobic respiration, but many microbial eukaryotes have lost this function through reductive evolution. their modified mitochondria are known as hydrogenosomes or mitosomes depending on whether or not they produce molecular hydrogen. the intestinal parasite entamoeba histolytica contains mitosomes whose role in cellular metabolism is unclear. only three proteins have been shown thus far to reside in these organelles: the molecular chaperones hsp10 and hsp60 and ...200717951687
programmed cell death in entamoeba histolytica induced by the aminoglycoside g418.this study presents morphological and biochemical evidence of programmed cell death (pcd) in entamoeba histolytica induced by exposure of trophozoites to the aminoglycoside antibiotic g418. morphological characteristics of pcd, including cell shrinkage, reduced cellular volume, nuclear condensation, dna fragmentation and vacuolization were observed, with preservation of trophozoite membrane integrity. pcd is orchestrated biochemically by alterations in intracellular ion fluxes. in g418-treated t ...200717975094
regulation of the inflammatory immune response by the cytokine/chemokine network in amoebiasis.amoebiasis is caused by the protozoa entamoeba histolytica and persists as one of the leading parasitic diseases affecting millions worldwide. this parasite invades the intestinal mucosa, causing amoebic colitis and ulcers. it may also spread to other organs, mainly the liver, causing amoebic liver abscess (ala). current research efforts have focused on the development of specific diagnostic tests and animal models searching for a better understanding of the complex physiopathology of this disea ...200718042174
novel mitochondrion-related organelles in the anaerobic amoeba mastigamoeba balamuthi.unicellular eukaryotes that lack mitochondria typically contain related organelles such as hydrogenosomes or mitosomes. to characterize the evolutionary diversity of these organelles, we conducted an expressed sequence tag (est) survey on the free-living amoeba mastigamoeba balamuthi, a relative of the human parasite entamoeba histolytica. from 19 182 ests, we identified 21 putative mitochondrial proteins implicated in protein import, amino acid interconversion and carbohydrate metabolism, two c ...200718045382
colitis amebiasis with symptom of occasional dripped anal bleeding.colitis amebiasis is usually characterized by bloody and mucous diarrhea, abdominal pain and anal discomfort. however, there is unusual manifestation of colitis amebiasis, such as occasional dripped anal bleeding, which sometimes spouted. therefore, we often do not suspect such symptoms for colitis amebiasis. laboratory examination includes complete laboratory test, coagulation and hematologic test, ict tbc and colonoscopy. the pathology anatomy examination reveals positive results of trophozoit ...200718046065
[elisa test for the detection of entamoeba histolytica in stool specimens]. 200718053480
structure and content of the entamoeba histolytica genome.the intestinal parasite entamoeba histolytica is one of the first protists for which a draft genome sequence has been published. although the genome is still incomplete, it is unlikely that many genes are missing from the list of those already identified. in this chapter we summarise the features of the genome as they are currently understood and provide previously unpublished analyses of many of the genes.200718063096
antimicrobial susceptibility of shigella flexneri and s. dysenteriae isolated from stool specimens of patients with bloody diarrhoea in mwanza, tanzania.this study was conducted to determine frequency and pattern of antimicrobial susceptibility of shigella species isolated from stool specimens collected from patients presenting with bloody diarrhoea in mwanza city, tanzania. the study was carried out from october 2004 to october 2005 and involved patients attending sekou toure regional hospital and butimba health centre. bacteriological cultures were done at the national institute for medical research laboratory. a total of 489 patients (median ...200718087897
[probable amebic brain abscess in a homosexual man with an entamoeba histolytica liver abscess].a 51-year-old japanese-brazilian homosexual man was admitted to a hospital because of fever, headache and right epigastralgia. he had been homosexual for 20 years. an abdominal ct revealed a liver abscess and microscopic examination of the pus of the drainage revealed cystic forms of entamoeba histolytica. oral administration of metronidazole 2,250 mg/day was started for amebic liver abscess. he complained of severe throbbing headache, and magnetic resonance imaging (mri) of the brain showed a b ...200718095503
two or more enteropathogens are associated with diarrhoea in mexican children.diarrhoeal diseases constitute a major public health problem, particularly in the developing world, where the rate of mortality and morbidity is very high. the purpose of this study was to conduct a 2 years and 3 months study in order to determine the prevalence of five enteropathogen diarrheogenic agents in mexico city.200718162140
intestinal protozoa and helminths among terena indians in the state of mato grosso do sul: high prevalence of blastocystis hominis.a parasitological survey was carried out among terena indians living in the tereré settlement in the municipality of sidrolândia, state of mato grosso do sul, brazil. single samples of feces from 313 indians were processed by means of the spontaneous sedimentation method. in the population studied, 73.5% were infected with at least one intestinal parasite or commensal. protozoa predominated. blastocystis hominis (40.9%), entamoeba coli (33.2%) and entamoeba histolytica/entamoeba dispar (31.6%) w ...200718200414
effect of solar disinfection on viability of intestinal protozoa in drinking water.the effect of solar disinfection on the viability of intestinal protozoa giardia lamblia, microsporidia sp., cryptosporidium parvum, cyclospora cyatenensis and entamoeba histolytica in drinking water was studied as compared to chlorine disinfection. the protozoa were collected from stool samples, to infect to the distilled water. chlorinated water samples were prepared at concentration of 4 ppm, and the parasites were incubated overnight at room temperature with the treated water. sun treatment ...200717580569
detection of entamoeba histolytica/dispar in stool specimens by using enzyme-linked immunosorbent assay in the population of jeddah city, saudi arabia.this study determined the prevalence of intestinal parasites, particularly pathogenic entamoeba sp. (e. histolytica), in patients attending three hospitals in jeddah city, king abdulaziz university hospital, king abdulaziz hospital and king fahad hospital for gastro-intestinal troubles. 186 stool specimens were examined microscopically for parasites and by elisa kit (e. histolytica ii) for true e. histolytica. 83 samples (44.6%) were positive by microscopy for at least one parasite. of which, 23 ...200717580574
prevalence of intestinal parasites among primary schoolchildren in derna district, libya.the prevalence of intestinal parasites and some hygienic factors was evaluated in primary schoolchildren in derna district. a total of 1039 stool specimens were examined by direct smear and formaline-ether concentration methods. the results showed that 31% of the children were infected with at least one or two parasites. these parasites were giardia lamblia (12.7%), blastocystis hominis (6.7%), entamoeba histolytica/ entamoeba dispar (6.6%), entamoeba coli (3.2%), e. hartmanni (1.0%), enterobius ...200717580578
detection and differentiation of entamoeba histolytica and entamoeba dispar isolates in clinical samples by pcr.a total of 140 out of 180 outpatients attended misr university for science and technology hospital complained of abdominal pain, diarrhoea and/or dysentery. stool examination showed 47 (33.6%) had entamoeba sp., 36 (25.7%) had cysts and 11 (7.9%) had trophozoites. of 40 asymptomatic ones, 4 (10%) had cysts. a total of 51 positive stool samples for entamoeba sp. (40 cysts & 11 trophozoites) were tested by ne-sted polymerase chain reaction (n-pcr) and restriction enzyme digestion (red) to clarify ...200717580582
entamoeba histolytica: adp-ribosylation of secreted glyceraldehyde-3-phosphate dehydrogenase.in addition to its classic glycolytic role, glyceraldehyde-3-phosphate dehydrogenase (gapdh) has been implicated in many activities unrelated to glycolysis, such as membrane fusion, binding to host proteins and signal transduction. gapdh can be the target of several modifications that allow incorporation to membranes and possible regulation of its activity; among these modifications is mono-adp-ribosylation. this post-translational modification is important for the regulation of many cellular pr ...200717586498
two rab7 isotypes, ehrab7a and ehrab7b, play distinct roles in biogenesis of lysosomes and phagosomes in the enteric protozoan parasite entamoeba histolytica.rab7 small gtpase plays a crucial role in the regulation of trafficking to late endosomes, lysosomes and phagosomes. while most eukaryotes encode a single rab7, the parasitic protist entamoeba histolytica possesses nine rab7. in this study, to understand the significance of the presence of multiple rab7 isotypes, a role of two representative rab7 isotypes, ehrab7a and ehrab7b, was investigated. ehrab7b was exclusively localized to acidic vacuoles containing lysosomal proteins, e.g. amoebapore-a ...200717359234
prevalence of enteric protozoa in human immunodeficiency virus (hiv)-positive and hiv-negative men who have sex with men from sydney, australia.a prospective, comparative study of the prevalence of enteric protozoa was determined among human immunodeficiency virus (hiv)- positive and hiv-negative men who have sex with men (msm) in sydney, australia. a total of 1,868 patients submitted stool specimens; 1,246 were from msm (628 hiv positive and 618 hiv positive) and 622 from non-msm were examined over a 36-month period. a total of 651 (52.2%) stool specimens from msm were positive for protozoa compared with 85 (13%) from non-msm. there wa ...200717360882
late experimental amebic liver abscess in hamster is inhibited by cyclosporine and n-acetylcysteine.during early experimental amebic liver abscess in hamsters (ealah), acute inflammation is primarily responsible for tissue damage. however, during the late stages of this process, the relative contribution to tissue destruction of both parasite factors and host response is unknown. in the present work, the role of the cellular immune response in tissue damage during ealah is explored by using the immunosuppressor drug cyclosporine a (csa). csa treatment inhibits tissue damage after 72 h (but not ...200717362925
transcriptional and secretory responses of entamoeba histolytica to mucins, epithelial cells and bacteria.invasive intestinal amebiasis, caused by entamoeba histolytica, is initiated with attachment of trophozoites to the colonic mucous layer, mucous disruption and/or depletion, and adherence to and cytolysis of host epithelial and inflammatory cells. a current working model of intestinal amebiasis suggests that the microenvironment of the host intestine, particularly intestinal mucins and the bacterial biofilm, may influence the behavior of pathogenic amebae. the invasive phenotype is dependent on ...200717362964
genome re-duplication and irregular segregation occur during the cell cycle of entamoeba histolytica.heterogeneity of genome content is commonly observed in axenic cultures of entamoeba histolytica. cells with multiple nuclei and nuclei with heterogenous genome contents suggest that regulatory mechanisms that ensure alternation of dna synthesis and mitosis are absent in this organism. therefore, several endo-reduplicative cycles may occur without mitosis. the data also shows that unlike other endo-reduplicating organisms, e.histolytica does not undergo a precise number of endo-reduplicative cyc ...200717592766
[nitric oxide participation during amoebic liver abscess development].nitric oxide participates in both physiological and pathophysiological functions, and it plays an important role in the mammalian immune system in killing or inhibiting the growth of many pathogens, including parasites, viruses and bacteria. entamoeba histolytica is a protozoan parasite that causes amoebiasis, which is characterized by intestinal damage and amoebic liver abscess development. the development of amoebic liver abscess in hamsters is similar to that in humans, whereas mice are resis ...200717593605
[evaluation of parasitology laboratory results of a group of people older than 15 years of age in kutahya].this research has been based on microscopic examination of stool specimens taken from 675 persons older than 15 years of age. the examinations were conducted in parasitology laboratory of the dumlupinar university hospital. laboratory examinations of stools were done with native and formalin-ethyl acetate sedimentation methods. different intestinal parasites were found in 52 (7.7%) of the stool specimens. at least one parasite species was found in 3.11% of women and 4.59% of men. the prevalence ...200717594654
[investigation of intestinal parasites in food workers in hospitals in aydin, turkey].food workers are an important risk group for intestinal parasite contamination and dissemination. in the present study food workers, working in food preparation and distribution in the adnan menderes university hospital, aydin state hospital and 82. yil state hospital, were screened for the presence of intestinal parasites. out of 58 food workers 22 were females and 36 were males, and the age of workers ranged from 20 to 56. all workers included in the study answered a questionnaire concerned wi ...200717594656
[distribution of intestinal parasites detected in camlihemşin healthcare center during the period from july 2005 to january 2007].in the present study, 142 persons admitted to the camlihemşin healthcare center between july 2005 and january 2007, carriage of intestinal parasites was investigated in 93 male and 49 female patients. all of the stool samples were examined by using native-lugol technique. cellophane tape method was applied to the 0-19 age group. parasite cysts and/or eggs were found in total of 17,6 % of the patients. of the patients carrying parasites, 64% (16/25) was female, and 36% (9/25) was male. giardia in ...200717594658
use of recombinant entamoeba histolytica cysteine proteinase 1 to identify a potent inhibitor of amebic invasion in a human colonic model.cysteine proteinases are key virulence factors of the protozoan parasite entamoeba histolytica. we have shown that cysteine proteinases play a central role in tissue invasion and disruption of host defenses by digesting components of the extracellular matrix, immunoglobulins, complement, and cytokines. analysis of the e. histolytica genome project has revealed more than 40 genes encoding cysteine proteinases. we have focused on e. histolytica cysteine proteinase 1 (ehcp1) because it is one of tw ...200717513563
eradication of amebiasis in a large institution for adults with mental retardation in taiwan.investigation of a program to eradicate amebiasis using consecutive intensive mass screenings followed by medication in a large institute for adults with mental retardation in taiwan.200717520540
a novel nested multiplex polymerase chain reaction (pcr) assay for differential detection of entamoeba histolytica, e. moshkovskii and e. dispar dna in stool samples.e. histolytica, a pathogenic amoeba, is indistinguishable in its cyst and trophozoite stages from those of non-pathogenic e. moshkovskii and e. dispar by light microscopy. we have developed a nested multiplex pcr targeting a 16s-like rrna gene for differential detection of all the three morphologically similar forms of e. histolytica, e. moshkovskii and e. dispar simultaneously in stool samples.200717524135
adherence-inhibitory intestinal immunoglobulin a antibody response in baboons elicited by use of a synthetic intranasal lectin-based amebiasis subunit vaccine.we designed an amebiasis subunit vaccine that is constructed by using four peptide epitopes of the galactose-inhibitable lectin heavy subunit that were recognized by intestinal secretory immunoglobulin a (iga) antibodies from immune human subjects. these epitopes are contained in the region encompassing amino acids 758 to 1134 of the lectin heavy subunit, designated lc3. baboons (papio anubis) are natural hosts for entamoeba histolytica; naturally infected baboons raised in captivity possess ser ...200717526742
characterization of entamoeba histolytica alpha-actinin2.we have cloned and characterized a second alpha-actinin isoform in entamoeba histolytica. this protein, alpha-actinin2, has a n-terminal actin-binding domain, a c-terminal calcium-binding domain and an intervening rod domain containing two spectrin repeats. the protein binds and cross-links actin filaments in a calcium-dependent manner. therefore alpha-actinin2 is a genuine alpha-actinin except for the shorter rod domain compared to the rod domain of isoforms of higher organisms. a alpha-actinin ...200717537529
the potential usefulness of the modified kato thick smear technique in the detection of intestinal sarcocystosis during field surveys.a total of 479 stool specimens were collected from rural communities of ubon ratchathani province, thailand and examined by two techniques: the modified kato thick smear and the direct smear. the prevalence of opisthorchis viverrini (14.8%), hookworm (10.2%), sarcocystis spp (4.6%), taenia spp (2.9%), strongyloides stercoralis (2.1%), giardia lamblia (1.2%), echinostoma spp (0.6%), ascaris lumbricoides (0.4%), entamoeba histolytica (0.2%), chilomastix mesnili (0.2%) and endolimax nana (0.2%) wer ...200717539271
amebic liver abscess in hiv-infected patients, republic of korea. 200717552123
replacement of the essential dictyostelium arp2 gene by its entamoeba homologue using parasexual genetics.cell motility is an essential feature of the pathogenesis and morbidity of amoebiasis caused by entamoeba histolytica. as motility depends on cytoskeletal organisation and regulation, a study of the molecular components involved is key to a better understanding of amoebic pathogenesis. however, little is known about the physiological roles, interactions and regulation of the proteins of the entamoeba cytoskeleton.200717553170
crystallization and preliminary crystallographic analysis of cysteine synthase from entamoeba histolytica.entamoeba histolytica, the causative agent of human amoebiasis, is essentially anaerobic, requiring a small amount of oxygen for growth. it cannot tolerate the higher concentration of oxygen present in human tissues or blood. however, during tissue invasion it is exposed to a higher level of oxygen, leading to oxygen stress. cysteine, which is a vital thiol in e. histolytica, plays an essential role in its oxygen-defence mechanisms. the major route of cysteine biosynthesis in this parasite is th ...200717554175
crystal structure of calcium binding protein-1 from entamoeba histolytica: a novel arrangement of ef hand motifs.calcium plays a pivotal role in the pathogenesis of amoebiasis, a major disease caused by entamoeba histolytica. several ef-hand containing calcium-binding proteins (cabps) have been identified from e. histolytica. even though these proteins have very high sequence similarity, they bind to different target proteins in a ca2+ dependent manner, leading to different functional pathways (yadava et al., mol biochem parasito 1997;84:69-82; chakrabarty et al., j biol chem 2004;279:12898-12908) the crys ...200717554780
the entamoeba histolytica genome: primary structure and expression of proteolytic enzymes.a number of studies have shown that peptidases and in particular cysteine peptidases constitute major pathogenicity factors in entamoeba histolytica. recent studies have suggested that a considerable number of genes coding for proteolytic enzymes are present within the e. histolytica genome and questions remain about the mode of expression of the various molecules.200717567921
prevalence of intestinal protozoa in an aborigine community in pahang, malaysia.the objective was to estimate the prevalence of intestinal protozoa among the aborigines and to determine the problems regarding the infection. the study was carried out in january 2006 in pos senderut, pahang, malaysia. samples of faeces were collected from children and adults and these were fixed in pva and trichrome staining was carried out. from the 130 individuals studied, 94 (72.3%) were positive with at least one intestinal protozoa. nine intestinal protozoa namely blastocystis hominis, g ...200717568378
morbidity due to schistosoma mansoni--entamoeba histolytica coinfection in hamsters (mesocricetus auratus).data on schistosoma mansoni-entamoeba histolytica coinfection are scarce in the literature. in the present study, hamsters that had been infected for 70 days with schistosoma mansoni (le strain) were inoculated via the portal vein with two strains of trophozoites of entamoeba histolytica: icb-egg (highly virulent) and icb-rps (non-virulent). the most evident result of coinfection was increased morbidity and mortality, in comparison with either of the infections alone. histologically, there were ...200717568883
[urticaria and parasites: case report and general view over the most common pathogens of chronic urticaria].chronic urticaria is a disease with numerous aetiologies. in case of blood hypereosinophilia a parasitosis is probable an should be mentioned. infections with echinococcus and helminths can cause ige mediated release of histamine. different cytokines are involved and lead to chronic urticaria as well. there are only a few case repoorts about chronic urticaria caused by amoebiasis. the transmission of amoebas is faeco oral and the pathogen can be detected with stool examinations or with testing o ...200717569439
entamoeba histolytica: ouabain-insensitive na(+)-atpase activity.our aim was to determine the presence of sodium pumps in entamoeba histolytica. it is shown through the measurement of ouabain-sensitive atpase activity and immunoblotting that e. histolytica does not express (na(+)+k(+))atpase. on the other hand, we observed a na(+)-atpase with the following characteristics: (1) stimulated by na(+) or k(+), but these effects are not addictive; (2) the apparent affinity is similar for na(+) and k(+) (k(0.5) = 13.3 +/- 3.7 and 15.4 +/- 3.1mm, respectively), as we ...200717574551
the role of the secretory immune response in the infection by entamoeba histolytica.intestinal infection with the protozoan parasite entamoeba histolytica elicits a local immune response with rising of specific secretory iga (siga) antibodies detectable in several compartments associated to mucosa. anti-amoebic siga antibodies have been reported in faeces, saliva, bile and breast milk from dysenteric patients and research trying to elucidate their role in protection has recently intensified. iga antibodies inhibit the in vitro adherence of e. histolytica trophozoites to epithel ...200717576362
primary structure, expression and localization of two intermediate subunit lectins of entamoeba dispar that contain multiple cxxc motifs.we have recently identified 2 surface proteins in entamoeba histolytica as intermediate subunits of galactose- and n-acetyl-d-galactosamine-inhibitable lectin (ehigl1 and ehigl2); these proteins both contain multiple cxxc motifs. here, we report the molecular characterization of the corresponding proteins in entamoeba dispar, which is neither pathogenic nor invasive. two igl genes encoding 1110 and 1106 amino acids (edigl1 and edigl2) were cloned from 2 strains of e. dispar. the amino acid seque ...200717803840
kinetic modeling can describe in vivo glycolysis in entamoeba histolytica.glycolysis in the human parasite entamoeba histolytica is characterized by the absence of cooperative modulation and the prevalence of pyrophosphate-dependent (over atp-dependent) enzymes. to determine the flux-control distribution of glycolysis and understand its underlying control mechanisms, a kinetic model of the pathway was constructed by using the software gepasi. the model was based on the kinetic parameters determined in the purified recombinant enzymes, and the enzyme activities, and st ...200717824961
identification of an entamoeba histolytica serine-, threonine-, and isoleucine-rich protein with roles in adhesion and cytotoxicity.entamoeba histolytica is a leading cause of parasitic death globally. however, the molecular framework regulating pathogenesis is poorly understood. we have previously used expression profiling to identify entamoeba genes whose expressions were strictly associated with virulent strains (r. c. macfarlane and u. singh, infect. immun. 74:340-351, 2006). one gene, which we have named ehstirp (entamoeba histolytica serine-, threonine-, and isoleucine-rich protein), was exclusively expressed in virule ...200717827347
differences in protein profiles of the isolates of entamoeba histolytica and e. dispar by surface-enhanced laser desorption ionization time-of-flight mass spectrometry (seldi-tof ms) proteinchip assays.surface-enhanced laser desorption ionization time of flight mass spectrometry (seldi-tof ms) proteinchip assays with weak cationic exchange chips were used for protein profiling of different isolates of entamoeba histolytica and e. dispar. when seldi-tof ms spectra of cell lysates from e. histolytica strain hm-1:imss were compared with those from four other laboratory strains (200:nih, hk-9, dkb, and saw755cr) grown under the same culture conditions, different peak patterns of seldi-tof ms were ...200717846790
viability studies of pure carbon- and nitrogen-doped nanotubes with entamoeba histolytica: from amoebicidal to biocompatible structures. 200717849378
[a case of amebic brain abscess].amebic brain abscess is a rare and usually fatal complication of entamoeba histolytica infections. we successfully treated a patient with this infection accompanied by brain, liver and pulmonary abscesses. treatment consisted of administration of metronidazole through a nasogastric tube, and drainage of the brain abscess. a 51-year-old male patient presented with a two-week history of fever, severe back pain, and chest pain. liver and pulmonary abscesses were drained upon admission. biopsy of th ...200717867313
detection of diarrhoea-causing protozoa in general practice patients in the netherlands by multiplex real-time pcr.the diagnostic value of a multiplex real-time pcr for the detection of entamoeba histolytica, giardia lamblia and cryptosporidium parvum/cryptosporidium hominis was evaluated by comparing the pcr results obtained with those of routinely performed microscopy of faecal samples from patients consulting their general practitioner (gp) because of gastrointestinal complaints. analysis of 722 faecal dna samples revealed that the prevalence of g. lamblia was 9.3% according to pcr, as compared to 5.7% by ...200717714523
epidemiology of amoebic liver abscess in mexico: the case of sonora. 200717716437
Refresh
firstprev
...51525354555657585960...
nextlast
Displaying items 5401 - 5500 of 7191