Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
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| inflammation, complement, ischemia and amoebic survival in acute experimental amoebic liver abscesses in hamsters. | we have examined the role of inflammatory cells, ischemia and serum complement on the development of acute experimental amoebic liver abscess in hamsters (aealah). in hamsters made leukopenic by whole body radiation (800 rad) and daily intraperitoneal glycogen injections, the absence of inflammatory cells and liver tissue damage surrounding the parasites resulted in their rapid (24 h) disappearance from the liver, which showed no lesions. focal liver ischemia, always present in control aealah wi ... | 2004 | 15215052 |
| resistance of entamoeba histolytica to the cysteine proteinase inhibitor e64 is associated with secretion of pro-enzymes and reduced pathogenicity. | cysteine proteinases (cps) have been considered suitable targets for the development of antiparasitic drugs. to assess the importance of cps for the growth and pathogenicity of the protozoan parasite entamoeba histolytica we have cultured amoebae in the presence of various cysteine proteinase inhibitors (cpis). it was found that broad range cpis, which are membrane permeable and rapidly enter the cell, are highly toxic at micromolar concentrations, and all attempts to generate e. histolytica mut ... | 2004 | 15215238 |
| overexpression of myosin ib in living entamoeba histolytica enhances cytoplasm viscosity and reduces phagocytosis. | the human parasite entamoeba histolytica is an ancient protozoan that expresses only one unconventional myosin, which has homology with myosin ib from other amoebae. myosin ib is involved in phagocytosis of human cells by e. histolytica. in this work, we developed a microrheological technique, analysing magnetic phagosomes, which allowed us to probe the density of the f-actin network in living cells. using this technique, we showed that overexpression of myosin ib led to an increase in cytoplasm ... | 2004 | 15226399 |
| protozoal infections in the developmentally disabled: often overlooked cause of rectal digging and fecal smearing. | 2004 | 15226486 | |
| parasite-specific antibody and cytokine profiles in newborns from plasmodium falciparum and entamoeba histolytica/dispar-infected mothers. | passage of parasites and their antigens across the placenta occurs with metazoan as well as protozoan parasites, and this study addressed to which extent exposure to and infection of mothers with plasmodium spp. and entamoeba histolytica/dispar has sensitized their offspring for parasite-specific immune responses. while at delivery none of the mothers presented with an acute malaria attack, 42% were seropositive for p. falciparum. in half of the mothers cysts of e. histolytica/dispar were detect ... | 2004 | 15059189 |
| entamoeba histolytica trophozoites transfer lipophosphopeptidoglycans to enteric cell layers. | transfer of antigens frequently follows adhesion of protozoan parasites to host cells. we were interested in such transfer from the entamoeba surface to enterocytes following adhesion of trophozoites. therefore, cocultures of enterocytes in vitro and ex vivo with entamoeba histolytica (strain hm-1:imss) or entamoeba dispar (strain saw760) trophozoites were processed for immunocytochemistry. the eh5 monoclonal antibody against amoebic proteophosphoglycans marked a dotted pattern on the apical sid ... | 2004 | 15064119 |
| accurate diagnosis is essential for amebiasis. | 2004 | 15069733 | |
| indirect determination of nitric oxide production by reduction of nitrate with a freeze-thawing-resistant nitrate reductase from escherichia coli mc1061. | preparation of a nitrate reductase lysate of escherichia coli mc1061 to measure nitrate and nitrite in biologic fluids is described. to obtain the crude bacterial lysate containing nitrate reductase activity, e. coli mc1061 was subjected to 16-20 freeze-thawing cycles, from -70 to 60 degrees c, until nitrite reductase activity was < or = 25%. nitrate reductase activity was detected mainly in the crude preparation. to validate the nitrate reduction procedure, standard nitrate solutions (1.6-100 m ... | 2004 | 15081902 |
| mitosomes of entamoeba histolytica are abundant mitochondrion-related remnant organelles that lack a detectable organellar genome. | the existence of mitochondrion-related relict organelles (mitosomes) in the amitochondrial human pathogen entamoeba histolytica and the detection of extranuclear dna-containing cytoplasmic structures (ehkos) has led to the suggestion that a remnant genome from the original mitochondrial endosymbiont might have been retained in this organism. this study reports on the mutually exclusive distribution of cpn60 and extranuclear dna in e. histolytica and on the distribution of cpn60-containing mitoso ... | 2004 | 15133087 |
| expression in fibroblasts and in live animals of entamoeba histolytica polypeptides ehcp112 and ehadh112. | ehcpadh is an immunogenic, heterodimeric protein that is formed by ehcp112 (cysteine protease) and ehadh112 (adhesin), polypeptides involved in entamoeba histolytica's cytopathic effect, target-cell adherence and phagocytosis. the ehcpadh complex is located in the plasma membrane and cytoplasmic vacuoles. here, the independent expression of ehcp112 and ehadh112 in fibroblasts and hamsters was analysed. also investigated was the immunological response in animals independently inoculated with plas ... | 2004 | 15133088 |
| microbial contamination of drinking water and disease outcomes in developing regions. | drinking water is a major source of microbial pathogens in developing regions, although poor sanitation and food sources are integral to enteric pathogen exposure. gastrointestinal disease outcomes are also more severe, due to under-nutrition and lack of intervention strategies in these regions. poor water quality, sanitation and hygiene account for some 1.7 million deaths a year world-wide (3.1% of all deaths and 3.7% of all daly's), mainly through infectious diarrhoea. nine out of 10 such deat ... | 2004 | 15138046 |
| contact of entamoeba histolytica with baby hamster kidney-21 (bhk-21) cell line on cysteine proteinase activity. | entamoeba histolytica, the causative agent of amoebiasis and amoebic liver abscess, lyses host cells by direct contact using surface lectins and releases cysteine proteinase (cp). virulence of e. histolytica is directly related to activity of its cp. the relationship of cp activity and cytotoxicity has not been established. the present study was carried out to explore the events following contact of e. histolytica with target cells. | 2004 | 15147121 |
| entamoeba histolytica alcohol dehydrogenase 2 (ehadh2) as a target for anti-amoebic agents. | the current use of metronidazole as an anti-amoebic agent causes significant side-effects. the purpose of this study was to identify alternative compounds with which to treat amoebiasis. | 2004 | 15150165 |
| [the 'bull's eye' pattern in hepatic tomography]. | invasive fungal infections are more commonly found in patients who develop neutropenia after chemotherapy. a 4-year-old girl with diagnosis of acute lymphoid leukemia developed febrile neutropenia after chemotherapy. broad spectrum antibiotics and antimycotic therapy were initiated. candida albicans was isolated and entamoeba histolytica was observed in stool examination. chronic disseminated candidiasis had developed and was treated with amphotericin b, initially, and fluconazol. computed tomog ... | 2004 | 15239596 |
| detection and genotyping of entamoeba histolytica, entamoeba dispar, giardia lamblia, and cryptosporidium parvum by oligonucleotide microarray. | entamoeba histolytica, giardia lamblia, and cryptosporidium parvum are the most frequently identified protozoan parasites causing waterborne disease outbreaks. the morbidity and mortality associated with these intestinal parasitic infections warrant the development of rapid and accurate detection and genotyping methods to aid public health efforts aimed at preventing and controlling outbreaks. in this study, we describe the development of an oligonucleotide microarray capable of detecting and di ... | 2004 | 15243091 |
| identification of genomic responses to collagen binding by trophozoites of entamoeba histolytica. | attachment of entamoeba histolytica trophozoites to collagen is a known stimulus for parasite activation, leading to subsequent tissue destruction and invasion. to identify cellular mechanisms of trophozoite activation, we assessed global variations in gene expression during collagen interaction with e. histolytica. a shotgun dna microarray was constructed by use of 9600 random inserts from an e. histolytica genomic dna library. through differential hybridization, key differences between gene ex ... | 2004 | 15243916 |
| pyogenic and amebic liver abscesses. | pyogenic and amebic liver abscesses are the two most common hepatic abscesses. amebic abscesses are more common in areas where entamoeba histolytica is endemic, whereas pyogenic abscesses are more common in developed countries. pyogenic abscess severity is dependent on the bacterial source and the underlying condition of the patient. amebic liver abscess is more prevalent in individuals with suppressed cell-mediated immunity, men, and younger people. the right lobe of the liver is the most likel ... | 2004 | 15245694 |
| inhibition of gene expression with double strand rna interference in entamoeba histolytica. | in order to inhibit gene expression in entamoeba histolytica, we have developed a method based on expressing double strand rna interference constructs in stable transformants. the 5' end of eh dia was cloned head to head with an intervening non-specific stuffer fragment in the e. histolytica expression vector pjst4. this construct was transformed in e. histolytica hm1:imss trophozoites and stable transformants were selected with 20microg/ml g418. our results show that expression of eh dia was co ... | 2004 | 15249205 |
| histopathology of cutaneous amebiasis. | cutaneous amebiasis (ca) is the manifestation in the skin and underlying soft tissues of the pathogenic properties of entamoeba histolytica, which may be the only expression of the infection or may be associated with disease in other organs. so far, there have been only isolated case reports on this disease. we herein report the histopathologic findings on a series of seven cases, six adults and one child, of ca. the most common findings include ulcers, areas of necrosis, mixed inflammatory infi ... | 2004 | 15249857 |
| calcium binding protein 1 of the protozoan parasite entamoeba histolytica interacts with actin and is involved in cytoskeleton dynamics. | blocking expression of ehcabp1, a calmodulin-like, four ef-hand protein from the protozoan parasite entamoeba histolytica, resulted in inhibition of cellular proliferation. in this paper we report that ehcabp1 is involved in dynamic changes of the actin cytoskeleton. both endocytosis and phagocytosis were severely impaired in cells where ehcabp1 expression was blocked by inducible expression of the antisense rna. in wild-type cells both actin and ehcabp1 were found to co-localize in phagocytic c ... | 2004 | 15252130 |
| multiple parasite infections and their relationship to self-reported morbidity in a community of rural côte d'ivoire. | concomitant parasitic infections are common in the developing world, yet most studies focus on a single parasite in a narrow age group. we investigated the extent of polyparasitism and parasite associations, and related these findings to self-reported morbidity. | 2004 | 15256525 |
| enteric infection in relapse of inflammatory bowel disease: importance of microbiological examination of stool. | previous reports have suggested that diarrhoeal relapses of inflammatory bowel disease (ibd) may be associated or confused with enteric infection, and that treatment of such infections with appropriate antibiotics may be beneficial. to re-evaluate the suggestion that enteric infection is rare and microbiological testing of stool not routinely necessary in patients presenting with relapse of ibd, we have reviewed the incidence of concurrent infection in patients presenting in relapse over a recen ... | 2004 | 15256979 |
| [screening and expression of recombinant human monoclonal antibody fab fragments specific to entamoeba histolytica]. | to prepare recombinant human monoclonal antibody fab fragments specific to the surface antigen of entamoeba histolytica. | 2004 | 15281441 |
| diagnostic potentials of copro-antigen detection based elisa, compared to microscopy in intestinal amoebiasis. | ninety three patients clinically presumed to have intestinal amoebiasis were chosen and stool samples were collected from all of them. stool samples were subjected to microscopic examination and entamoeba copro-antigens detection using entamoeba and entamoeba ii tests. out of 93 clinically positive samples, 51 (54.8%) were found positive by microscopy, while 49 (52.7%) were detected by entamoeba test as having antigens specific for e. histolytica/e. dispar (88.24% sensitivity). among 49 specimen ... | 2004 | 15287182 |
| selective identification of the pathogenic e. histolytica in fresh stool samples using polymerase chain reaction (pcr). | stool samples from 93 individuals clinically presumed to have intestinal amoebiasis and subjected to microscopic examination and dna extraction. the pcr amplification was performed using two sets of primers that differentiate between pathogenic and nonpathogenic entamoeba dna. of 93 clinically positive cases, 51 (54.8%) were positive by microscopy, while 53 (56.9%) were detected by pcr as having dna specific for either e. histolytica / e. dispar. a specificity of 85.71% and a sensitivity of 92.1 ... | 2004 | 15287183 |
| signal transduction through the gal-galnac lectin of entamoeba histolytica involves a spectrin-like protein. | capping followed by uroid formation in entamoeba histolytica has been implicated in resistance against the host immune response during development of amoebiasis. the amebic actomyosin cytoskeleton is essential for such a process. a protein from the spectrin family co-localizes with the gal-galnac lectin during capping of this surface protein complex. co-localization is not observed when capping of the gal-galnac lectin is specifically inhibited by production of the carboxyl-terminal region of it ... | 2004 | 15287584 |
| [isolated pleural amebiasis: about one case in france]. | isolated pleural amebiasis is exceptional in the world and specially in france. | 2004 | 15292852 |
| the distribution of entamoeba histolytica and entamoeba dispar in northern, central, and southern iran. | the present study was carried out from august 1999 through february 2002 in order to determine the prevalence of entamoeba histolytica and entamoeba dispar in three different climatic regions of iran by using a pcr-rflp method. a total of 16,592 stool samples were randomly collected from different age-groups in central, northern, and southern iran in both urban and rural areas. the samples were examined by direct and formalin-ether concentration methods. a total of 226 samples were positive for ... | 2004 | 15293045 |
| [investigation of intestinal parasites in aids patients]. | in this study, enteric parasites were investigated in the stool samples of 38 aids patients (23 with chronic diarrhea and 15 without diarrhea) prospectively. at least three stool samples from each patient were investigated microscopically for ova or trophozoites. the samples were concentrated with formol-ether method and wet preparations stained with lugol were examined. in addition, the concentrated samples were stained with modified asid-fast (kinyoun's), rhodamine-auramine, modified trichrom ... | 2004 | 15293911 |
| cytopathologic and genetic diagnosis of pulmonary amebiasis: a case report. | amebiasis is a parasitic infection with entamoeba histolytica. pulmonary amebiasis is rare since the infection is commonly manifested as amebic colitis or liver abscess. most pleuropulmonary amebiasis is seen in patients with amebic liver abscesses. a pulmonary amebic lesion without either a liver abscess or amebic colitis is extremely rare. thus, reported cases of sputum cytologic diagnosis of a pulmonary amebic lesion from a patient without a liver abscess are also very rare. | 2004 | 15296344 |
| etiology of acute diarrhea in adults in southwestern nigeria. | 2004 | 15297567 | |
| amebic liver abscess. | amebic liver abscess is the most common extraintestinal manifestation of infection with entamoeba histolytica, and it is associated with significant morbidity and mortality. in this article the most recent available information is reviewed relating to epidemiology, pathogenesis, presentation, diagnosis, and treatment. we reviewed thousands of cases of amebic liver abscess in the medical literature and present that information as it pertains to mortality, gender, anatomic location of abscesses, a ... | 2004 | 15301125 |
| [nitric oxide and anti-protozoan chemotherapy]. | constitutive nitric oxide (no) is generated by constitutively expressed types of no-synthase enzymes (nos-i and -iii), being involved in physiological processes such as nervous transmission and vasodilatation. inducible no, synthesized by the no-synthase isoform nos-ii, is an anti-pathogen and tumoricidal agent. however, inducible no production requires a tight control because of cytotoxic and immune-modulation activity. no produced by human and canine macrophages has long been demonstrated to b ... | 2004 | 15305696 |
| cyclosporin a inhibits calcineurin (phosphatase 2b) and p-glycoprotein activity in entamoeba histolytica. | cyclosporin a (csa) inhibits the proliferation of several protozoan parasites through blocking the activity of calcineurin (cn) or p-glycoproteins (pgp). we report here, that inhibition of the proliferation of entamoeba histolytica trophozoites, the causal agent of human amebiasis, is due to interference of the phosphatase activity of cn, in a similar fashion to the effect of this immunosuppressive drug on t lymphocytes. the non-immunosuppressive csa analog psc-833, which binds pgp without inter ... | 2004 | 15313136 |
| involvement of raft-like plasma membrane domains of entamoeba histolytica in pinocytosis and adhesion. | lipid rafts are highly ordered, cholesterol-rich, and detergent-resistant microdomains found in the plasma membrane of many eukaryotic cells. these domains play important roles in endocytosis, secretion, and adhesion in a variety of cell types. the parasitic protozoan entamoeba histolytica, the causative agent of amoebic dysentery, was determined to have raft-like plasma membrane domains by use of fluorescent lipid analogs that specifically partition into raft and nonraft regions of the membrane ... | 2004 | 15322032 |
| [the role of parasites and fungi in secondary infertility]. | parasite-host relationships can cause diminished or absent ability to conceive, ectopic pregnancy or pregnancy with undesired course. | 2004 | 15327187 |
| immunosuppressive treatment inhibits the development of amebic liver abscesses in hamsters. | the aim of the present study was to determine if the inflammation and/or immunosuppression induced by entamoeba histolytica may contribute to amebic invasion. | 2004 | 15328476 |
| prospective evaluation of lactose malabsorption by lactose hydrogen breath test in individuals infected with entamoeba histolytica and passing cysts. | the aim of the present prospective study was to detect lactose malabsorption in subjects in northern india infected with entamoeba histolytica and passing cysts. the study group included forty-one patients with e. histolytica cysts in at least one of three consecutive faecal samples. lactose malabsorption was detected by a lactose h2 breath test. the results were compared with those of forty controls subjects. thirty-two of forty-one (78.0 %) subjects passing e. histolytica cysts had lactose mal ... | 2004 | 15333150 |
| rab5-associated vacuoles play a unique role in phagocytosis of the enteric protozoan parasite entamoeba histolytica. | in mammals, rab5 and rab7 play a specific and coordinated role in a sequential process during phagosome maturation. here, we report that rab5 and rab7 in the enteric protozoan parasite entamoeba histolytica, ehrab5 and ehrab7a, are involved in steps that are distinct from those known for mammals. ehrab5 and ehrab7a were localized to independent small vesicular structures at steady state. priming with red blood cells induced the formation of large vacuoles associated with both ehrab5 and ehrab7a ... | 2004 | 15347665 |
| role of entamoeba histolytica in acute watery diarrhea in hospitalized under-five children. | 2004 | 15347882 | |
| [hepatic abscesses in childhood: retrospective study about 33 cases observed in new-caledonia between 1985 and 2003]. | hepatic abscesses in childhood are rarely observed in europe. the aim of this word was to study how to diagnose and how to treat an hepatic abscess. | 2004 | 15350993 |
| pyruvate formate lyase (pfl) and pfl activating enzyme in the chytrid fungus neocallimastix frontalis: a free-radical enzyme system conserved across divergent eukaryotic lineages. | fermentative formate production involves the activity of pyruvate formate lyase, an oxygen-sensitive enzyme that employs a glycyl radical in its reaction mechanism. while common among anaerobic prokaryotes, this enzyme has so far been found in only two distantly related eukaryotic lineages, anaerobic chytridiomycetes and chlorophytes. sequence comparisons of homologues from the chytridiomycetes piromyces and neocallimastix, the chlorophyte chlamydomonas, and numerous prokaryotes suggest a single ... | 2004 | 15352329 |
| synthesis, characterization and in vitro anti-amoebic activity of new palladium(ii) complexes with 5-nitrothiophene-2-carboxaldehyde n(4)-substituted thiosemicarbazones. | reaction between [pd(dmso)(2)cl(2)] (dmso=dimethylsulfoxide) and n(4)-substituted thiosemicarbazones derived from 5-nitrothiophene-2-carboxaldehyde (l) afforded the complexes [pd(l)cl(2)]. these new complexes have been characterized by elemental analyses and spectroscopic studies. spectroscopic studies reveal that thionic sulfur and azomethine nitrogen atom of thiosemicarbazones are coordinated to metal ion. the testing of the anti-amoebic activity of these complexes against the protozoan parasi ... | 2004 | 15358294 |
| polymicrobial infections in children with diarrhoea in a rural area of jordan. | polymicrobial infections associated with diarrhoea are common in developing countries. stool specimens were collected from 220 patient children and 100 controls. potential pathogenic agents isolated from 143 (65%) children were identified by molecular and standard microbiological methods. co-infections with two or more agents were detected in 50 (35%) cases. escherichia coli, shigella dysenteriae, giardia and entamoeba histolytica were found to be predominant. the etiologic agents could not be d ... | 2004 | 15364112 |
| role of cysteine proteinase of entamoeba histolytica in target cell death. | the bacterial flora of the intestine plays an important role in the virulence caused by entamoeba histolytica. cysteine proteinase (cp), an amoebic virulence factor, plays a major role in host cell destruction. the mechanism of increased virulence following bacterial co-association is not understood. we studied cp of e. histolytica hm1:imss which was co-associated with escherichia coli k12 strain pre-incubated with galnac or cp specific inhibitor e 64. co-association of e. histolytica with bacte ... | 2004 | 15376772 |
| structural analysis of the acetaldehyde dehydrogenase activity of entamoeba histolytica alcohol dehydrogenase 2 (ehadh2), a member of the adhe enzyme family. | the adhe family of enzymes are bifunctional acetaldehyde dehydrogenase (aldh)/alcohol dehydrogenase (adh) enzymes that probably arose from the fusion of genes encoding separate aldh and adh enzymes. here we have used the entamoeba histolytica alcohol dehydrogenase 2 (ehadh2) enzyme as a prototype to analyze the structure and function of the aldh domain of adhe enzymes. we find that the n-terminal domain of ehadh2, encompassing amino acids 1-446, is sufficient for aldh activity, consistent with t ... | 2004 | 15383290 |
| multiple cerebral amoebic abscesses in a child. | 2004 | 15455218 | |
| prevention of intestinal amebiasis by vaccination with the entamoeba histolytica gal/galnac lectin. | prevention of intestinal infection by entamoeba histolytica would block both invasive disease and parasite transmission. the amebic gal/galnac lectin mediates parasite adherence to the colonic surface and fecal anti-lectin iga is associated with protection from intestinal reinfection in children. we tested if vaccination with the e. histolytica gal/galnac lectin could prevent cecal infection in a c3h mouse model of amebic colitis. two trials using native lectin purified from the parasite and two ... | 2004 | 14741152 |
| expression of amoebapores is required for full expression of entamoeba histolytica virulence in amebic liver abscess but is not necessary for the induction of inflammation or tissue damage in amebic colitis. | entamoeba histolytica trophozoites produce amoebapores, a family of small amphipathic peptides capable of insertion into bacterial or eukaryotic membranes and causing cellular lysis. recently, e. histolytica trophozoites that are totally deficient in the production of amoebapore-a were created through a gene silencing mechanism (r. bracha, y. nuchamowitz, and d. mirelman, eukaryot. cell 2:295-305, 2003). here we tested the virulence of amoebapore a(-) trophozoites in models of the two major form ... | 2004 | 14742508 |
| influence of human leukocyte antigen class ii alleles on susceptibility to entamoeba histolytica infection in bangladeshi children. | the association of antibody responses with both innate and acquired immunity to amebiasis indicate that cd4+ t cells play a role in protection against entamoeba histolytica infection. to test this hypothesis, we compared the genotype frequencies of human leukocyte antigen (hla) class ii alleles in a cohort of bangladeshi children intensively monitored for e. histolytica infection for a 3-year period. | 2004 | 14745711 |
| [indigenous amebic liver abscess. presentation of a case]. | 2004 | 14746764 | |
| gastrointestinal parasite infestation. | twenty-five percent of the world's population could be suffering parasitic infestation. highest prevalence is in underdeveloped agricultural and rural areas in the tropical and subtropical regions. in some areas incidence may reach 90% of the population. in contrast, some major economic projects intended to promote local development have, paradoxically, caused parasitic proliferation, e.g. bilharziasis in egypt and sudan and chagas disease in brazil. the commonest cosmopolitan gastrointestinal p ... | 2004 | 14749961 |
| an entamoeba histolytica line/sine pair inserts at common target sites cleaved by the restriction enzyme-like line-encoded endonuclease. | the non-long-terminal-repeat (non-ltr) retrotransposons (also called long interspersed repetitive elements [lines]) are among the oldest retroelements. here we describe the properties of such an element from a primitive protozoan parasite, entamoeba histolytica, that infects the human gut. this 4.8-kb element, called ehline1, is present in about 140 copies dispersed throughout the genome. the element belongs to the r4 clade of non-ltr elements. it has a centrally located reverse transcriptase do ... | 2004 | 14871947 |
| the stool examination reports amoeba cysts: should you treat in the face of over diagnosis and lack of specificity of light microscopy? | amoebiasis is a common clinical diagnosis in tropical settings and clinicians continue to treat asymptomatic carriers diagnosed by light microscopy. a minority of carriers, however, are infected with entamoeba histolytica and the remaining with the non-pathogenic entamoeba dispar. we compared the diagnostic results of 298 asymptomatic residents of aracaju, brazil, obtained by different diagnostic methods, and ascertained their clinical symptoms, to highlight the implications for practitioners. f ... | 2004 | 14959971 |
| origins, lineage-specific expansions, and multiple losses of tyrosine kinases in eukaryotes. | tyrosine kinases are important components of metazoan signaling pathways, and their mutant forms are implicated in various malignancies. searching the sequences from the genomes of 28 eukaryotes and the genbank, we found tyrosine kinases not only in metazoans but also in the green algae chlamydomonas reinhardtii, the potato late blight pathogen phytophthora infestans, and the protozoan pathogen entamoeba histolytica, contrary to the current view that tyrosine kinases are animal-specific. based o ... | 2004 | 14963097 |
| amoebiasis distribution in the past: first steps using an immunoassay technique. | the identification of parasites in ancient human faeces is compromised by differential preservation of identifiable parasite structures. however, protein molecules can survive the damage of the environment and can be detected even after centuries. in this paper it is shown that is possible to detect copro-antigen of entamoeba histolytica in historic and prehistoric human faecal remains, using a commercially available enzyme immunoassay (elisa) kit. the kit uses monoclonal antibody-peroxidase con ... | 2004 | 14964807 |
| cryopreservation of protozoan parasites. | conventional methods for the propagation and preservation of parasites in vivo or in vitro have some limitations, including the need for labor, initial isolation and loss of strains, bacterial, and fungal contamination, and changes in the original biological and metabolic characteristics. all these disadvantages are considerably reduced by cryopreservation. in this study, we examined the effects of various freezing conditions on the survival of several protozoan parasites after cryopreservation. ... | 2004 | 14969677 |
| solution structure of the pore-forming protein of entamoeba histolytica. | amoebapore a is a 77-residue protein from the protozoan parasite and human pathogen entamoeba histolytica. amoebapores lyse both bacteria and eukaryotic cells by pore formation and play a pivotal role in the destruction of host tissues during amoebiasis, one of the most life-threatening parasitic diseases. amoebapore a belongs to the superfamily of saposin-like proteins that are characterized by a conserved disulfide bond pattern and a fold consisting of five helices. membrane-permeabilizing eff ... | 2004 | 14970207 |
| present characteristics of symptomatic entamoeba histolytica infection in the big cities of japan. | medical records, for 2000 and 2001, of symptomatic amoebic patients who were treated at our hospitals in tokyo, yokohama and osaka were studied retrospectively for the purpose of gathering epidemiological data on symptomatic entamoeba histolytica infection. a total of 58 patients were treated. fifty-five of them were male, and 96% of the male patients were japanese. the mean age of patients was 44.9 years old, and 91% of patients contracted the disease in japan. fifty-six per cent of the male pa ... | 2004 | 14979590 |
| in vitro and in vivo interaction of entamoeba histolytica gal/galnac lectin with various target cells: an immunocytochemical analysis. | the gal/galnac lectin of entamoeba histolytica trophozoites plays an important role in adhesion. the distribution and final destiny of the lectin during the interaction with host cells are poorly understood. using monoclonal and polyclonal antibodies against the lectin we studied by immunocytochemistry the in vitro and in vivo interaction of e. histolytica trophozoites with human and hamster hepatocytes. we also analyzed the presence and distribution of the lectin in a mouse model of intestinal ... | 2004 | 14984834 |
| a description of the mei2-like protein family; structure, phylogenetic distribution and biological context. | the schizosaccharomyces pombe mei2 gene encodes an rna recognition motif (rrm) protein that stimulates meiosis upon binding a specific non-coding rna and subsequent accumulation in a "mei2-dot" in the nucleus. we present here the first systematic characterization of the family of proteins with characteristic mei2-like amino acid sequences. mei2-like proteins are an ancient eukaryotic protein family with three identifiable rrms. the c-terminal rrm (rrm3) is unique to mei2-like proteins and is the ... | 2004 | 14986133 |
| effect of human milk and colostrum on entamoeba histolytica. | many defense factors of the mother's colostrum or milk protect infants from intestinal, respiratory and systemic infections. in the present study, we investigated the effect of colostrum and mature human milk on e. histolytica parasites in vitro. | 2004 | 14991951 |
| determination of the prevalence of entamoeba histolytica and e. dispar in the pernambuco state of northeastern brazil by a polymerase chain reaction. | previous studies using methods varying from traditional serologic tests to molecular biology techniques have shown that in northeastern brazil, entamoeba dispar was more prevalent than e. histolytica. in this study, the prevalence was established by using e. histolytica stool antigen detection kits and a polymerase chain reaction (pcr) with genomic dna extracted from cultured trophozoites in all four-nuclei, amoeba-positive samples from a population living in macaparana in northeastern brazil. a ... | 2004 | 14993636 |
| ameboma mimicking carcinoma of the cecum: case report. | 2004 | 14997156 | |
| the use of real-time pcr to identify entamoeba histolytica and e. dispar infections in prisoners and primary-school children in ethiopia. | in ethiopia, it is generally unknown what proportion of the amoebic infections commonly found, by microscopy, in humans are caused by non-invasive entamoeba dispar rather than the potentially invasive e. histolytica. faecal samples were therefore collected from 363 primary-school students and 409 prisoners from various regions of ethiopia. each of these samples was checked for entamoeba infection by the microscopical examination of formol-ether concentrates. dna was then extracted from the 213 s ... | 2004 | 15000730 |
| evaluation of recombinant fragments of entamoeba histolytica gal/galnac lectin intermediate subunit for serodiagnosis of amebiasis. | we have recently identified a 150-kda surface antigen of entamoeba histolytica as an intermediate subunit (igl) of galactose- and n-acetyl-d-galactosamine-inhibitable lectin, which is a cysteine-rich protein consisting of 1,101 amino acids (aa) and containing multiple cxxc motifs in amino acid sequences. in the present study, full-length igl except for the signal sequences (aa 14 to 1088) and three fragments of igl-the n-terminal part (aa 14 to 382), the middle part (aa 294 to 753), and the c-te ... | 2004 | 15004055 |
| simultaneous detection of entamoeba histolytica, giardia lamblia, and cryptosporidium parvum in fecal samples by using multiplex real-time pcr. | entamoeba histolytica, giardia lamblia, and cryptosporidium are three of the most important diarrhea-causing parasitic protozoa. for many years, microscopic examination of stool samples has been considered to be the "gold standard" for diagnosis of e. histolytica, g. lamblia, and c. parvum infections. recently, more specific and sensitive alternative methods (pcr, enzyme-linked immunosorbent assay, and direct fluorescent-antibody assay) have been introduced for all three of these parasitic infec ... | 2004 | 15004079 |
| the ehadh112 recombinant polypeptide inhibits cell destruction and liver abscess formation by entamoeba histolytica trophozoites. | the entamoeba histolytica ehcpadh complex, formed by a cysteine proteinase (ehcp112) and an adhesin (ehadh112), is involved in adherence, phagocytosis and cytolysis. this makes this complex an attractive candidate as a vaccine against amoebiasis. here, we produced the recombinant polypeptide ehadh243, which includes the adherence epitope detected by a monoclonal antibody against the ehcpadh complex. ehadh243 was purified, and the effect of the polypeptide on in vitro and in vivo virulence was st ... | 2004 | 15009028 |
| purification and biochemical characterisation of a membrane-bound alpha-glucosidase from the parasite entamoeba histolytica. | an alpha-glucosidase was solubilised from a mixed membrane fraction of entamoeba histolytica and purified to homogeneity by a two-step procedure consisting of ion exchange chromatography in a mono q column and affinity chromatography in concanavalin a-sepharose. although the enzyme failed to bind the lectin, this step rendered a homogenous and more stable enzyme preparation that resolved into a single polypeptide of 55 kda after sds-page. as measured with 4-methylumbelliferyl-alpha-d-glucopyrano ... | 2004 | 15013735 |
| entamoeba histolytica: kinetic and molecular evidence of a previously unidentified pyruvate kinase. | we report the kinetic characterization of a previously unidentified pyruvate kinase (pk) activity in extracts from entamoeba histolytica trophozoites. this activity was about 74% of the activity of pyruvate phosphate dikinase. ehpk differed from most pks in that its ph optimum was 5.5-6.5 and was inhibited by high pep concentrations (1-5mm); these are concentrations at which pk is usually assayed. the optimal temperature was above 40 degrees c with negligible activity below 20 degrees c. ehpk ex ... | 2004 | 15013784 |
| common intestinal parasites. | intestinal parasites cause significant morbidity and mortality. diseases caused by enterobius vermicularis, giardia lamblia, ancylostoma duodenale, necator americanus, and entamoeba histolytica occur in the united states. e. vermicularis, or pinworm, causes irritation and sleep disturbances. diagnosis can be made using the "cellophane tape test." treatment includes mebendazole and household sanitation. giardia causes nausea, vomiting, malabsorption, diarrhea, and weight loss. stool ova and paras ... | 2004 | 15023017 |
| diabetes and amoebiasis: a high risk encounter. | amoebiasis is the second most common parasitic disease worldwide. it occurs mainly in developing countries. a high percentage of people in countries where it is endemic are asymptomatic carriers. it results in severe disease that can be fatal in rare cases. diabetics are at increased risk of exposure as travel to countries where it is endemic becomes more frequent, as indicated by the present case. this patient suffered from amoebiasis that produced an amoeboma which is most rare in cases of col ... | 2004 | 15029104 |
| the iron-sulfur cluster assembly genes iscs and iscu of entamoeba histolytica were acquired by horizontal gene transfer. | iron-sulfur (fes) proteins are present in all living organisms and play important roles in electron transport and metalloenzyme catalysis. the maturation of fes proteins in eukaryotes is an essential function of mitochondria, but little is known about this process in amitochondriate eukaryotes. here we report on the identification and analysis of two genes encoding critical fes cluster (isc) biosynthetic proteins from the amitochondriate human pathogen entamoeba histolytica. | 2004 | 15040816 |
| [epidemiological, social, and sanitary aspects in an area of the rio negro, state of amazonas, with special reference to intestinal parasites and chagas' disease]. | a cross-sectional study was carried out on the residents of one in every four dwellings in the town of barcelos (in the northern part of the state of amazonas, on the right bank of the rio negro, 490 kilometers from manaus by river), in order to evaluate social and sanitary conditions and specific indicators for intestinal parasites and chagas' infection. during the survey, two questionnaires were applied, a household one to evaluate social and sanitary aspects, and an individual one, for social ... | 2004 | 15042222 |
| cytogenetic study of metronidazole and three metronidazole analogues in cultured human lymphocytes with and without metabolic activation. | metronidazole (mtz) and other nitroimidazole derivatives have been extensively used to treat infections caused by protozoa and anaerobic bacteria. however, the need for new derivatives with similar therapeutic activity but lower toxicity to human beings prevails. on this purpose, three metronidazole analogues were synthesized, namely: 1-(p-methylphenacyl)-2-methyl-4-nitro imidazole (cpme), 1-(p-methoxyphenacyl)-2-methyl-4-nitroimidazole (cpmeo), and 1-(p-fluorphenacyl)-2-methyl-4-nitroimidazole ... | 2004 | 15046779 |
| membrane lipid composition protects entamoeba histolytica from self-destruction by its pore-forming toxins. | the protozoan parasite and human pathogen entamoeba histolytica is protected against killing by its own lytic effector proteins. amoebae withstand doses of amoebapores, their pore-forming polypeptides, that readily kill human jurkat t cells. moreover, the polypeptides do not bind to the amoebic surface membrane as evidenced by using fluorescently labelled amoebapores and confocal laser microscopy. experiments employing liposomes as a minimalistic membrane system and the major isoform amoebapore ... | 2004 | 15094050 |
| zoonotic intestinal parasites in papio anubis (baboon) and cercopithecus aethiops (vervet) from four localities in ethiopia. | a total of 59 faecal samples from ranging papio anubis (baboons) and another 41 from cercopithecus aethiops (vervet) from the rift valley areas of ethiopia were microscopically examined to determine the prevalence and species of major gastro-intestinal parasites of zoonotic importance. faecal smears were prepared from fresh faecal samples, stained using modified ziehl-neelsen method and microscopically examined. about 3 gm of the dropping was also preserved separately in clean and properly label ... | 2004 | 15099809 |
| rna interference in protozoan parasites. | rna interference or rnai is defined as the mechanism through which gene-specific, double-stranded rna (dsrna) triggers degradation of homologous transcripts. besides providing an invaluable tool to downregulate gene expression in a variety of organisms, it is now evident that rnai extends its tentacles into both the nucleus and the cytoplasm and is involved in a variety of gene silencing phenomena. here we review the current status of rnai in protozoan parasites that cause diseases of considerab ... | 2004 | 15104593 |
| stereotypic and specific elements of the human colonic response to entamoeba histolytica and shigella flexneri. | the clinical presentations of bacillary dysentery caused by shigella, and amoebic dysentery caused by the protozoan parasite entamoeba histolytica, can be indistinguishable, with both organisms causing colonic mucosal damage and ulceration. however, the two organisms are quite distinct, and have very different pathogenic mechanisms. this raises the fundamental question of whether the similar clinical manifestations reflect a stereotypic response of the human gut to mucosal injury, or whether the ... | 2004 | 15104595 |
| involvement of protein kinases on the process of erythrophagocytis by entamoeba histolytica. | erythrophagocytic capacity of trophozoites of entamoeba histolytica is considered a factor in the virulence of this pathogenic protozoan. we present evidence showing that such activity resembles the ingestion of microorganisms by highly differentiated phagocytic cells, such as macrophages. previous treatment of the trophozoites with genistein or tyrphostin, inhibitors of tyrosine protein kinases, with staurosporine, a protein kinase c inhibitor, and wortmannin, a fungal metabolite that inhibits ... | 2004 | 15109979 |
| a unique rab gtpase, ehraba, of entamoeba histolytica, localizes to the leading edge of motile cells. | entamoeba histolytica, an enteric protozoan parasite, infects 10% of the world's population leading to 50 million cases of invasive amoebiasis annually. parasite vesicle trafficking and motility, which relies on vesicle trafficking to deliver membrane and membrane components to the leading edge, are important for virulence however little is known about the molecular mechanisms regulating these functions. since rab gtpases are known modulators of vesicle trafficking we have characterized a rab gt ... | 2004 | 15110460 |
| synthesis, characterization and in vitro antiamoebic activity of 5-nitrothiophene-2-carboxaldehyde thiosemicarbazones and their palladium (ii) and ruthenium (ii) complexes. | synthesis of new palladium(ii) and ruthenium(ii) complexes of the type, [pd(l)cl(2)] and [ru(eta(4)-c(8)h(12))(l)cl(2)] [where, l = thiosemicarbazones derived from 5-nitrothiophene-2-carboxaldehyde and cycloalkylaminothiocarbonyl hydrazines] have been isolated by the reaction of [pd(dmso)(2)cl(2)] and [ru(eta(4)-c(8)h(12))(ch(3)cn)(2)cl(2)] with 5-nitrothiophene-2-carboxaldehyde thiosemicarbazones. the spectral data revealed that the thiosemicarbazones act as bidentate ligands, making use of thi ... | 2004 | 15110972 |
| short communication: misleading microscopy in amoebiasis. | high prevalences of intestinal amoebiasis are commonly reported by microscopy in ethiopia. in order to confirm the actual occurrence of entamoeba histolytica we collected 108 stool specimens from different hospitals & health centers from patients in whom haematophagous trophozoites were believed to be found. we detected only a single e. histolytica case while 77 (71.3%) were e. dispar and the remaining 30 samples were negative for both species by real-time pcr based on the small subunit ribosoma ... | 2004 | 15117312 |
| intestinal parasitic infections in hiv/aids and hiv seronegative individuals in a teaching hospital, ethiopia. | the magnitude of intestinal parasitic infection in human immunodeficiency virus (hiv) /aids patients requires careful consideration in the developing world. however, there have been very few studies addressing this issue in ethiopia. this study was conducted to determine the prevalence of intestinal parasitic infection in hiv/aids patients at jimma hospital, southwest ethiopia, between january and february 2002. stool specimens from hiv/aids patients and control groups were screened for intestin ... | 2004 | 15118206 |
| effects of piper longum fruit, piper sarmentosum root and quercus infectoria nut gall on caecal amoebiasis in mice. | the anti-amoebic effects of crude methanol extracts of piper longum fruit, piper sarmentosum root and quercus infectoria nut gall against entamoeba histolytica infecting the caecum of mice were studied. caecal amoebiasis in mice was induced by injection of entamoeba histolytica trophozoites directly into the caecum. the mice were then treated orally with the extract, a standard drug (metronidazole), or vehicle p.o. for five consecutive days, beginning 24 h after the infection and were examined o ... | 2004 | 15120461 |
| molecular cloning and characterization of a protein farnesyltransferase from the enteric protozoan parasite entamoeba histolytica. | genes encoding alpha- and beta-subunits of a putative protein farnesyltransferase (ft) from the enteric protozoan parasite entamoeba histolytica were obtained and their biochemical properties were characterized. deduced amino acid sequences of the alpha- and beta-subunit of e. histolytica ft (ehft) were 298- and 375-residues long with a molecular mass of 35.6 and 42.6 kda, and a pi of 5.43 and 5.65, respectively. they showed 24% to 36% identity to and shared common signature domains and repeats ... | 2004 | 14583615 |
| regulation of toll-like receptor-2 expression by the gal-lectin of entamoeba histolytica. | the gal/galnac lectin (gal-lectin) of entamoeba histolytica is a surface molecule involved in parasite adherence to host cells and is the most promising subunit vaccine candidate against amoebiasis. as macrophages are the major effector cells in host defense against amoebas, we studied the molecular mechanisms by which gal-lectin activates macrophage. microarray analysis showed that gal-lectin up-regulated mrnas of several cytokines and receptor genes involved in proinflammatory responses. the m ... | 2004 | 14630697 |
| effects of bisphosphonates on the growth of entamoeba histolytica and plasmodium species in vitro and in vivo. | the effects of a series of 102 bisphosphonates on the inhibition of growth of entamoeba histolytica and plasmodium falciparum in vitro have been determined, and selected compounds were further investigated for their in vivo activity. forty-seven compounds tested were active (ic(50) < 200 microm) versus e. histolytica growth in vitro. the most active compounds (ic(50) approximately 4-9 microm) were nitrogen-containing bisphosphonates with relatively large aromatic side chains. simple n-alkyl-1-hy ... | 2004 | 14695831 |
| molecular cloning, expression and characterization of a serine proteinase inhibitor gene from entamoeba histolytica. | serine proteinase inhibitors (serpins) are irreversible suicide inhibitors of proteinases that regulate a wide range of biological processes, including pathogen evasion of the host defence system. we report the cloning and characterization of a gene encoding a serpin from the protozoan parasite entamoeba histolytica (ehserp) that may function in this manner. the protein encoded by ehserp contains 371 amino acids with a predicted mass of 42.6 kda. antibodies to a 42 kda recombinant ehserp react s ... | 2004 | 14698428 |
| genes induced by a high-oxygen environment in entamoeba histolytica. | entamoeba histolytica, although a microaerophilic protozoan parasite, encounters a high-oxygen environment, during invasive amoebiasis. the parasite requires specific regulation of certain proteins to maintain its physiological functions to survive in the more oxygenated condition. our endeavor was to know how does amoeba adapt itself in a high-oxygen environment. reactive oxygen species (ros) was found to accumulate in an increasing concentration within the stressed trophozoites in a time-depen ... | 2004 | 14698431 |
| parasite and host contributions to the pathogenesis of amebic colitis. | 2004 | 14700586 | |
| identification and characterization of ehcabp2. a second member of the calcium-binding protein family of the protozoan parasite entamoeba histolytica. | entamoeba histolytica, an early branching eukaryote, is the etiologic agent of amebiasis. calcium plays a pivotal role in the pathogenesis of amebiasis by modulating the cytopathic properties of the parasite. however, the mechanistic role of ca(2+) and calcium-binding proteins in the pathogenesis of e. histolytica remains poorly understood. we had previously characterized a novel calcium-binding protein (ehcabp1) from e. histolytica. here, we report the identification and partial characterizatio ... | 2004 | 14711825 |
| bacterial expression of a human monoclonal antibody-alkaline phosphatase conjugate specific for entamoeba histolytica. | we previously produced human monoclonal antibody fab fragments specific to entamoeba histolytica in escherichia coli. in order to use these fab fragments for diagnostic purposes, an expression vector to produce a fusion protein of fab and alkaline phosphatase (phoa) in e. coli was designed and constructed. the e. coli phoa gene was fused to the 3' terminus of the gene encoding the heavy-chain fd region. the kappa and fd genes from a previously prepared antibody clone, cp33, which is specific for ... | 2004 | 14715571 |
| characterization of cytosine methylated regions and 5-cytosine dna methyltransferase (ehmeth) in the protozoan parasite entamoeba histolytica. | the dna methylation status of the protozoan parasite entamoeba histolytica was heretofore unknown. in the present study, we developed a new technique, based on the affinity of methylated dna to 5-methylcytosine antibodies, to identify methylated dna in this parasite. ribosomal dna and ribosomal dna circles were isolated by this method and we confirmed the validity of our approach by sodium bisulfite sequencing. we also report the identification and the characterization of a gene, ehmeth, encodin ... | 2004 | 14715927 |
| an intestinal parasitic protist, entamoeba histolytica, possesses a non-redundant nitrogen fixation-like system for iron-sulfur cluster assembly under anaerobic conditions. | we have characterized the iron-sulfur (fe-s) cluster formation in an anaerobic amitochondrial protozoan parasite, entamoeba histolytica, in which fe-s proteins play an important role in energy metabolism and electron transfer. a genomewide search showed that e. histolytica apparently possesses a simplified and non-redundant nif (nitrogen fixation)-like system for the fe-s cluster formation, composed of only a catalytic component, nifs, and a scaffold component, nifu. amino acid alignment and phy ... | 2004 | 14757765 |
| intestinal parasites among presumably healthy individuals in lebanon. | to determine the prevalence period of intestinal parasites among presumably healthy subjects in lebanon. | 2004 | 14758375 |
| effects of cd(+2), cu(+2), ba(+2) and co(+2) ions on entamoeba histolytica cysts. | the effects of cobalt, copper, cadmium and barium ions on the cysts of entamoeba histolytica (e. histolytica), an amebic dysentery agent, cultured in robinson medium were investigated. | 2004 | 14760778 |
| parasitic diseases of the heart. | the following chapter is one of a series of chapters in the volume entitled infections of the myocardium appearing in frontiers in bioscience. the full table of contents can be found at http://www.bioscience.org/current/special/tanowitz.htm. in this chapter, we review several parasitic infections involving the myocardium and pericardium. the most widely studied parasitic infection affecting the heart is chagas' disease or american trypanosomiasis. in this chapter we describe issues relating to c ... | 2004 | 14766402 |
| prevalence of parasitism among students of the karen hill-tribe in mae chame district, chiang mai province, thailand. | infection caused by intestinal parasites is still a common health problem in a poor-hygiene population especially for children in developing countries. a cross-sectional study was conducted among 781 karen students (age: 3 to 19, males: 325, females: 456) to determine the current status of intestinal parasitic infections in a mountainous area in the north of thailand. the study was drawn from three schools in the doi inthanon region, in mae chame district of chiang mai province, from december 20 ... | 2004 | 16083202 |
| microorganisms and parasites in chronic infective diarrhea. | to reveal the pattern of microorganisms in chronic infective diarrhea cases. | 2004 | 15931720 |