| stable transfection and continuous expression of heterologous genes in entamoeba invadens. | amoebiasis is spread by the ingestion of dormant entamoeba histolytica cysts. intervention of encystation could break the transmission cycle, thereby reducing disease burden. the model system used to study trophozoite to cyst differentiation is entamoeba invadens. here we describe an electroporation-based method for stable transfection of e. invadens with a plasmid peineo-luc containing the neomycin phosphotransferase gene under the control of e. invadens ribosomal protein gene s10 promoter. the ... | 2012 | 22426570 |
| efficacy of a gal-lectin subunit vaccine against experimental entamoeba histolytica infection and colitis in baboons (papio sp.). | to determine the efficacy of a gal-lectin based intranasal synthetic peptide vaccine, we developed a new experimental primate model of entamoeba histolytica intestinal infection. release of xenic e. histolytica trophozoites (5×10(6)) into the small bowel of baboons (papio sp.) resulted in a rapid intestinal anti-amebic antibody response and a brief infection; however, release of trophozoites directly into the cecum (5 baboons) elicited a sustained e. histolytica infection, as determined by quant ... | 2012 | 22406457 |
| programmed cell death in giardia. | programmed cell death (pcd) has been observed in many unicellular eukaryotes; however, in very few cases have the pathways been described. recently the early divergent amitochondrial eukaryote giardia has been included in this group. in this paper we investigate the processes of pcd in giardia. we performed a bioinformatics survey of giardia genomes to identify genes associated with pcd alongside traditional methods for studying apoptosis and autophagy. analysis of giardia genomes failed to high ... | 2012 | 22405231 |
| self-circularizing 5'-ets rnas accumulate along with unprocessed pre ribosomal rnas in growth-stressed entamoeba histolytica. | the primary transcript of rrna genes is a large pre rrna which is precisely processed to release the mature rrnas. the 5'-external transcribed spacer (ets) of rrna genes contains important sites for pre rrna processing. once the processing is accomplished the ets is rapidly degraded. we show that in growth-stressed cells of the human parasitic protist entamoeba histolytica the a'-a(0) sub-fragment of the 5'-ets accumulates to high levels as a family of rna molecules of size 666 to 912 nt. these ... | 2012 | 22396851 |
| biochemical, mutational and in silico structural evidence for a functional dimeric form of the ornithine decarboxylase from entamoeba histolytica. | entamoeba histolytica is responsible for causing amoebiasis. polyamine biosynthesis pathway enzymes are potential drug targets in parasitic protozoan diseases. the first and rate-limiting step of this pathway is catalyzed by ornithine decarboxylase (odc). odc enzyme functions as an obligate dimer. however, partially purified odc from e. histolytica (ehodc) is reported to exist in a pentameric state. | 2012 | 22389745 |
| novel protein-protein interactions between entamoeba histolyticad-phosphoglycerate dehydrogenase and phosphoserine aminotransferase. | physical interactions between d-phosphoglycerate dehydrogenase (ehpgdh) and phosphoserine aminotransferase (ehpsat) from an enteric human parasite entamoeba histolytica was observed by pull-down assay, gel filtration chromatography, chemical cross-linking, emission anisotropy, molecular docking and molecular dynamic simulations. the protein-protein complex had a 1:1 stochiometry with a dissociation constant of 3.453 × 10(-7) m. ionic interactions play a significant role in complex formation and ... | 2012 | 22386871 |
| endoplasmic reticulum stress-sensing mechanism is activated in entamoeba histolytica upon treatment with nitric oxide. | the endoplasmic reticulum stores calcium and is a site of protein synthesis and modification. changes in er homeostasis lead to stress responses with an activation of the unfolded protein response (upr). the entamoeba histolytica endomembrane system is simple compared to those of higher eukaryotes, as a canonical er is not observed. during amoebiasis, an infection of the human intestine and liver by e. histolytica, nitric oxide (no) triggers an apoptotic-like event preceded by an impairment of e ... | 2012 | 22384074 |
| multisite performance evaluation of an enzyme-linked immunosorbent assay for detection of giardia, cryptosporidium, and entamoeba histolytica antigens in human stool. | a novel fecal antigen detection assay for fresh and frozen human samples that detects but does not differentiate giardia spp, cryptosporidium spp, and entamoeba histolytica, the tri-combo parasite screen, was compared to three established enzyme-linked immunosorbent assays (elisas) at three international sites. it exhibited 97.9% sensitivity and 97.0% specificity, with positive and negative predictive values of 93.4% and 99.1%, respectively. the tri-combo test proved a reliable means to limit th ... | 2012 | 22378909 |
| toward low-cost affinity reagents: lyophilized yeast-scfv probes specific for pathogen antigens. | the generation of affinity reagents, usually monoclonal antibodies, remains a critical bottleneck in biomedical research and diagnostic test development. recombinant antibody-like proteins such as scfv have yet to replace traditional monoclonal antibodies in antigen detection applications, in large part because of poor performance of scfv in solution. to address this limitation, we have developed assays that use whole yeast cells expressing scfv on their surfaces (yeast-scfv) in place of soluble ... | 2012 | 22363793 |
| leptin signaling protects the gut from entamoeba histolytica infection. | the role of the adipose-derived hormone leptin, and leptin receptors, in signaling satiety to the central nervous system and regulating energy balance is well recognized. but leptin also acts on peripheral tissues such as skeletal muscles, adipose tissues, pancreas, liver, intestine and the immune system. the existence of different splice variants of leptin receptor and the numerous intracellular signaling pathways triggered by leptin make this a truly versatile system. two recent studies explor ... | 2014 | 22356851 |
| virtual screening, identification and in vitro testing of novel inhibitors of o-acetyl-l-serine sulfhydrylase of entamoeba histolytica. | the explosive epidemicity of amoebiasis caused by the facultative gastrointestinal protozoan parasite entamoeba histolytica is a major public health problem in developing countries. multidrug resistance and side effects of various available antiamoebic drugs necessitate the design of novel antiamobeic agents. the cysteine biosynthetic pathway is the critical target for drug design due to its significance in the growth, survival and other cellular activities of e. histolytica. here, we have scree ... | 2012 | 22355310 |
| effect of bovine lactoferrin in a therapeutic hamster model of hepatic amoebiasis. | entamoeba histolytica is the causative agent of amoebiasis, a disease that produces dysentery as a result of the perforation of the large intestine. this parasite often invades other organs, primarily the liver, leading to an amoebic liver abscess (ala), which can cause death. metronidazole is the drug of choice for the treatment of ala; however, it produces toxic side effects in patients. lactoferrin (lf) is a glycoprotein of the innate immune response that sequesters iron in the mucosae. lf po ... | 2012 | 22332957 |
| leptin protects host cells from entamoeba histolytica cytotoxicity by a stat3-dependent mechanism. | the adipocytokine leptin links nutritional status to immune function. leptin signaling protects from amebiasis, but the molecular mechanism is not understood. we developed an in vitro model of ameba-host cell interaction to test the hypothesis that leptin prevents ameba-induced apoptosis in host epithelial cells. we demonstrated that activation of mammalian leptin signaling increased cellular resistance to amebic cytotoxicity, including caspase-3 activation. exogenous expression of the leptin re ... | 2012 | 22331430 |
| cloning, expression and evaluation of the efficacy of a recombinant entamoeba histolytica cysteine proteinase (ehcp4) antigen in minipig. | cysteine proteinases 4 (ehcp4) of entamoeba histolytica are considered important for ameba pathogenicity. the recombinant gene was obtained by cloning and expression of the ehcp4 gene in heterologous host escherichia coli bl-21 (de3), were used to evaluate their ability to induce immune protective responses in minipig against challenge infection in a minipig-e. histolytica model. there was a 53.16% reduction (p<0.001) in the group of recovery of challenged e. histolytica compared with that in th ... | 2012 | 22326593 |
| establishment of a transient transfection system and expression of firefly luciferase in entamoeba invadens. | entamoeba invadens is used as a model system to study trophozoite to cyst differentiation since entamoeba histolytica, the causative agent of amoebiasis cannot encyst in culture. however, a system for introduction of cloned genes in e. invadens is not available. here we report an electroporation-based method for transfection of e. invadens tophozoites and demonstrate the expression of firefly luciferase reporter gene driven from the e. invadens ribosomal protein l3 promoter. the efficiency of lu ... | 2012 | 22321531 |
| evaluation of the intestinal microbial diversity in miniature pig after orally infected with entamoeba histolytica. | the objective of this study was to analyze the difference in intestinal microbial diversity between healthy and (entamoeba histolytica) orally infected minipig. enterobacterial repetitive intergenic consensus (eric)-pcr was applied to analyze this diversity and dynamic change, including the duodenum, jejunum, ileum, cecum, and rectum from healthy and orally infected minipig at different time points. the results showed that the intestinal microbial community of the control minipigs was stable and ... | 2012 | 22314784 |
| quantification of diarrhea risk related to wastewater contact in thailand. | wastewater reuse contributes to closing the nutrient recycling loop as a sustainable way of managing water resources. bangkok has over a thousand man-made drainage and irrigation canals for such purposes. its use for agricultural and recreational purposes has a long tradition in rural and peri-urban areas. however, the continuation of these practices is increasingly questioned since potential health risks are an issue if such practices are not appropriately managed. the microbial and chemical qu ... | 2012 | 22311100 |
| synthesis, characterization and antiamoebic activity of some hydrazone and azole derivatives bearing pyridyl moiety as a promising heterocyclic scaffold. | in an effort to develop effective antiamoebic agents, some hydrazones and azoles containing pyridyl moiety were synthesized and screened for in vitro antiamoebic activity against hm1:imss strain of entamoeba histolytica. among all the compounds, only five compounds (1, 3, 5, 9 and 11) were found to be better inhibitors of growth of e. histolytica than the reference drug metronidazole. the cytotoxic studies of these compounds on human breast cancer mcf-7 cell line revealed that all the compounds ... | 2012 | 22309914 |
| profiles of entamoeba histolytica-specific immunoglobulins in human sera. | to determine the profiles of anti-entamoeba histolytica (e. histolytica) iga, igg, and igm in sera of diarrheic and non-diarrheic individuals and partially characterize target antigens. | 2012 | 22305791 |
| porcine colon explants in the study of innate immune response to entamoeba histolytica. | human amebiasis is caused by the protozoan entamoeba histolytica. this protozoan is responsible for muco-hemorrhagic diarrhoea and liver abscess in affected populations. e. histolytica can be asymptomatic commensally confined to the intestinal lumen or can result in invasion of the colonic mucosa leading to ulceration and/or liver abscesses. recently, human colonic explants have been identified as valuable in the study of host-parasite interactions. here we investigated the potential of porcine ... | 2012 | 22297149 |
| obtaining of three recombinant antigens of entamoeba histolytica and evaluation of their immunogenic ability without adjuvant in a hamster model of immunoprotection. | a 30-kda surface collagen binding protein peroxiredoxin of entamoeba histolytica (ehcbp30) was evaluated either alone or fused to the chaperone (chp) or atpase (atp) domains of heat shock protein 70 of trypanosoma cruzi (tchsp70) as a vaccine candidate in a hamster model of experimental amoebic liver abscess (ala) development. three constructs were produced containing the ehcbp30 dna sequence, one expressing ehcbp30 and two expressing ehcbp30 fused to either chp or atp domains of tchsp70. high p ... | 2012 | 22266120 |
| human milk oligosaccharides reduce entamoeba histolytica attachment and cytotoxicity in vitro. | human milk oligosaccharides (hmo), complex sugars that are highly abundant in breast milk, block viral and bacterial attachment to the infant's intestinal epithelium and lower the risk of infections. we hypothesised that hmo also prevent infections with the protozoan parasite entamoeba histolytica, as its major virulence factor is a lectin that facilitates parasite attachment and cytotoxicity and binds galactose (gal) and n-acetyl-galactosamine. hmo contain gal, are only minimally digested in th ... | 2012 | 22264879 |
| newly visualized fibrillar collagen scaffolds dictate entamoeba histolytica invasion route in the human colon. | the extracellular matrix (ecm) and its role in the outcome of infectious diseases have been poorly investigated. in this study, we determined the impact of the collagen fibres architecture on the invasive process of the enteric parasite entamoeba histolytica. the behaviour of e. histolytica wild-type and silenced for the cysteine protease a5 (cp-a5) were compared on a three-dimensional collagen matrix and within human colon fragments for fibrillar collagen cleavage and migration. the interstitia ... | 2012 | 22233454 |
| amoebicidal activity of the rhizomes and aerial parts of allium sivasicum on entamoeba histolytica. | amebiasis is a severe illness caused by entamoebachistolytica. the aim of this study is to evaluate the in vitro amebicidal activity of the rhizomes and aerial parts of allium sivasicum, an endemic plant species from the flora of turkey. both extracts showed a time- and dose-dependent amebicidal action on the trophozoites. among the extracts tested, rhizomes of a. sivasicum showed the strongest amebicidal effect on the trophozoites. in the presence of the rhizome extract at 2.0 mg/ml concentrati ... | 2012 | 22215196 |
| [ileocecal ameboma: a case diagnosed by pathology and molecular biology]. | colonic ameboma is a rare benign inflammatory tumor due to the infection by entamoeba histolytica and poses frequently the problem of colon cancer. we report a case of a 52 year-old patient who presented a cecal amoeboma revealed by a painful mass in the right iliac fossa. radiologic and endoscopic examinations depicted a parietal thickening of the right colon and the cecum. a presumptive diagnosis of colon cancer was firstly discussed. confirmation of ameboma was made on pathological examinatio ... | 2012 | 24834662 |
| detection of entamoeba histolytica in experimentally induced amoebic liver abscess: comparison of three staining methods. | to compare the efficacy of three different tissue stains, namely haematoxylin and eosin (h&e), periodic-acid schiff (pas) and immunohistochemical (ihc) stains for detection of entamoeba histolytica (e. histolytica) trophozoites in abscessed liver tissues of hamster. | 2012 | 23569836 |
| amoebic ulcer of the male genitala: a rare case report. | amoebic ulcer of the penis is a very rare clinical entity. we report a case of amoebic ulcer of the glans penis in a 47-year-old male homosexual, symptomatic with severe pain and foul-smelling hemopurulent discharge of acute onset. he had received systemic antibiotics like ciprofloxacin and azithromycin prior to presentation with no improvement. diagnosis was confirmed by wet mount microscopic examination of the discharge. the patient responded well to a course of metronidazole. | 2010 | 21716788 |
| new insights into host-pathogen interactions during entamoeba histolytica liver infection. | amoebiasis is the third worldwide disease due to a parasite. the causative agent of this disease, the unicellular eukaryote entamoeba histolytica, causes dysentery and liver abscesses associated with inflammation and human cell death. during liver invasion, before entering the parenchyma, e. histolytica trophozoites are in contact with liver sinusoidal endothelial cells (lsec). we present data characterizing human lsec responses to interaction with e. histolytica and identifying amoebic factors ... | 2011 | 24466432 |
| caecal amoebic colitis mimicking a colorectal cancer. | intestinal entamoeba histolytica infection in the uk is rare but it can lead to colitis, abscess formation, colonic perforation and rarely amoeboma. although most patients are asymptomatic, it can present with a wide range of gastrointestinal symptoms depending on the phase of the infection. we present a case of amoebic colitis that caused diagnostic uncertainty by mimicking a colonic carcinoma. | 2011 | 24972391 |
| efficacy and safety of quinfamide versus secnidazole in the management of amoebic non-dysenteric colitis in children. | to compare the efficacy and safety of single doses of quinfamide and secnidazole in the treatment of amoebic non-dysenteric colitis in children. | 2000 | 23315350 |
| clinical studies on amoebiasis and giardiasis evaluating the efficacy of kutaja (holarrhena antidysenterica) in entamoeba histolytica cyst passers. | the clinical study records the clinical presentations of forty cases with amoebias and / or giardiasis including the efficacy of kutaja (holarrhena antidysenterica) in intestinal amoebiasis. e. h. cyst passers also have symptoms like loose motions, constipation, flatulence, abdominal cramping, diminished appetite and mucus in stools. patients with giardiasis have more tendency to diarrhoea and flatulence with no mucus in stools. 70 per cent good response was observed in e. h. cyst passers when t ... | 1986 | 22557529 |
| [pulmonary amebiasis; entamoeba histolytica schaudinn, 1903]. | | 1956 | 13323451 |
| multiplex pcr detection of cryptosporidium sp, giardia lamblia and entamoeba histolytica directly from dried stool samples from guinea-bissauan children with diarrhoea. | in developing countries, diarrhoea is the most common cause of death for children under five years of age, with giardia lamblia, cryptosporidium and entamoeba histolytica as the most frequent pathogenic parasites. traditional microscopy for stool parasites has poor sensitivity and specificity, while new molecular methods may provide more accurate diagnostics. in poor regions with sample storage hampered by uncertain electricity supply, research would benefit from a method capable of analysing dr ... | 2017 | 28446068 |
| intestinal parasitic infections: current status and associated risk factors among school aged children in an archetypal african urban slum in nigeria. | intestinal parasitic infections (ipis) among school aged children (sac) in nigeria remains endemic, hence the need for regular surveillance to attract the attention of policy makers. this cross-sectional study investigated the current prevalence and factors associated with intestinal parasitic infections among school aged children in an urban slum of lagos city, nigeria. | 2017 | 28711437 |
| antiprotozoal, antibacterial and antidiarrheal properties from the flowers of chiranthodendron pentadactylon and isolated flavonoids. | chiranthodendron pentadactylon larreat. (sterculiaceae) is a mexican plant used in traditional medicine for the treatment of heart disease symptoms and infectious diarrhea. | 2017 | 28539715 |
| profile of intestinal parasitosis among school-aged children in kiliba (eastern dr congo). | this study of feces sought to determine the prevalence of human intestinal parasites in the kiliba area of the eastern dr congo. feces of 602 school children aged from 9 to 20 years were collected from april to june 2014 and examined. direct analyses were supplemented with the kato and ritchie methods. the global prevalence of intestinal parasitosis in school-aged children in the kiliba area was 91.4 % [95 % ci: 87.6-94.3%]. the frequency of helminthiasis was high at 73.8 % (95 % ci: 68.4-78.6%) ... | 2017 | 28655684 |
| gastrointestinal parasites in captive and free-ranging cebus albifrons in the western amazon, ecuador. | currently, there is a lack of surveys that report the occurrence of gastrointestinal parasites in the white-headed capuchin monkey (cebus albifrons). we therefore assessed the presence and richness (= number of different parasite genera) of parasites in c. albifrons in wildlife refuges (n = 11) and in a free-ranging group near a human village (n = 15) in the ecuadorian amazon. in the 78 samples collected (median of 3 samples per animal), we identified a total of 6 genera of gastrointestinal para ... | 2017 | 28808619 |
| an integrated study of human and animal infectious disease in the lake victoria crescent small-holder crop-livestock production system, kenya. | the neglected zoonotic diseases (nzd) are an understudied group that are a major cause of illness throughout the developing world. in general, little is known about the prevalence and burden of nzds in affected communities, particularly in relation to other infectious diseases with which they are often co-endemic. we describe the design and descriptive epidemiological outputs from an integrated study of human and animal zoonotic and non-zoonotic disease in a rural farming community in western ke ... | 2017 | 28666412 |
| hookworm infection is associated with decreased cd4+ t cell counts in hiv-infected adult ugandans. | most studies evaluating epidemiologic relationships between helminths and hiv have been conducted in the pre-art era, and evidence of the impact of helminth infections on hiv disease progression remains conflicting. less is known about helminth infection and clinical outcomes in hiv-infected adults receiving antiretroviral therapy (art). we sampled hiv-infected adults for eight gastrointestinal parasites and correlated parasitic infection with demographic predictors, and clinical and immunologic ... | 2017 | 28542260 |
| high prevalence of enteroparasites in children from ribeirão preto, são paulo, brazil. | to determine the prevalence of intestinal parasites and possible associated factors. | 2017 | 28562805 |
| intestinal parasitic infections: current prevalence and risk factors among schoolchildren in capital area of the republic of marshall islands. | intestinal parasitic infections (ipis) among schoolchildren in republic of marshall islands (rmi) largely remains unknown, thus investigation on ipis status to establish the baseline data is urgently needed. this cross-sectional study intended to investigate the current ipis status and associated risk factors among schoolchildren at capital of rmi. single stool sample from 400 schoolchildren (207 boys and 193 girls) aged 9.73±2.50 yrs old was examined by employing merthiolate-iodine-formaldehyde ... | 2017 | 28847672 |
| molecular analysis of the enteric protozoa associated with acute diarrhea in hospitalized children. | pediatric diarrhea is a common cause of death among children under 5 years of age. in the current study, we investigated the frequency of intestinal parasites among 580 pediatric patients with chronic diarrhea. parasitic protozoa (all species combined) were detected by molecular tools in 22.9% of the children and the most common parasite was cryptosporidium spp. (15.1%). blastocystis hominis was detected in 4.7%, dientamoeba fragilis in 4%, giardia duodenalis in 1.7%, and entamoeba histolytica i ... | 2017 | 28824878 |
| evaluation of primitive ground water supplies as a risk factor for the development of major waterborne zoonosis in egyptian children living in rural areas. | endemic waterborne zoonosis frequently occurs in both developed and less developed countries. thus, bio-surveillance of waterborne zoonosis is a "necessity" for the implementation of effective preventive public health measures in egyptian rural areas. the primitive individual water supplies created by the rural agriculture population, primarily from ground water, usually maximize the customers' exposure to impurity pathogens via diffused humans and animal excreta or wastages. the current study a ... | 2017 | 28843417 |
| detection of cryptosporidium in stool samples of immunocompromised patients. | cryptosporidium species is the most common opportunistic enteric parasite encountered in the immunocompromised patients. considering the need to diagnose them early relies mostly on rapid tests such as antigen detection by immunochromatographic test (ict), elisa, and microscopy. however, the sensitivity and specificity varies with different methods and different kits used. this study was conducted to determine the intestinal parasitic profile in immunocompromised patients and to assess the diagn ... | 2017 | 28459014 |
| evaluation of the bd max enteric parasite panel for the detection of cryptosporidium parvum/hominis, giardia duodenalis and entamoeba histolytica. | conventional laboratory detection methods for gastrointestinal parasites are time consuming, require considerable technical expertise and may suffer from poor analytical sensitivity. this study sought to evaluate the automated bd max enteric parasite panel (epp) for the detection of cryptosporidium parvum/hominis, entamoeba histolytica and giardia duodenalis.methodolgy. a total of 104 known positive samples (43 cryptosporidium parvum/hominis and 61 g. duodenalis), 15 simulated samples (e. histol ... | 2017 | 28792380 |
| use of serologic responses against enteropathogens to assess the impact of a point-of-use water filter: a randomized controlled trial in western province, rwanda. | diarrhea is a leading contributor to childhood morbidity and mortality in sub-saharan africa. given the challenge of blinding most water, sanitation, and hygiene (wash) interventions, diarrheal disease outcome measures in wash intervention trials are subject to potential bias and misclassification. using the platform of a cluster-randomized controlled trial of a household-based drinking water filter in western province, rwanda, we assessed the impact of the drinking water filter on enteric seroc ... | 2017 | 28749764 |
| measuring changes in transmission of neglected tropical diseases, malaria, and enteric pathogens from quantitative antibody levels. | serological antibody levels are a sensitive marker of pathogen exposure, and advances in multiplex assays have created enormous potential for large-scale, integrated infectious disease surveillance. most methods to analyze antibody measurements reduce quantitative antibody levels to seropositive and seronegative groups, but this can be difficult for many pathogens and may provide lower resolution information than quantitative levels. analysis methods have predominantly maintained a single diseas ... | 2017 | 28542223 |
| self-reported infections during international travel and notifiable infections among returning international travellers, sweden, 2009-2013. | we studied food and water-borne diseases (fwds), sexually transmitted diseases (stds), vector-borne diseases (vbds) and diseases vaccinated against in the swedish childhood vaccination programme among swedish international travellers, in order to identify countries associated with a high number of infections. we used the national database for notifiable infections to estimate the number of fwds (campylobacteriosis, salmonellosis, giardiasis, shigellosis, ehec, entamoeba histolytica, yersinosis, ... | 2017 | 28753671 |
| occurrence and removal efficiency of parasitic protozoa in swedish wastewater treatment plants. | giardia intestinalis, cryptosporidium spp., entamoeba histolytica and dientamoeba fragilis are parasitic protozoa and causative agents of gastroenteritis in humans. g. intestinalis and cryptosporidium spp. in particular are the most common protozoa associated with waterborne outbreaks in high-income countries. surveillance of protozoan prevalence in wastewater and evaluation of wastewater treatment removal efficiencies of protozoan pathogens is therefore imperative for assessment of human health ... | 2017 | 28458199 |
| comparison of hemolytic activity of the intermediate subunit of entamoeba histolytica and entamoeba dispar lectins. | galactose and n-acetyl-d-galactosamine-inhibitable lectin of entamoeba histolytica has roles in pathogenicity and induction of protective immunity in rodent models of amoebiasis. recently, the intermediate subunit of the lectin, igl1, of e. histolytica has been shown to have hemolytic activity. however, the corresponding lectin is also expressed in a non-virulent species, entamoeba dispar, and another subunit, igl2, is expressed in the protozoa. therefore, in this study, we compared the activiti ... | 2017 | 28750000 |
| no detection of entamoeba histolytica by multiplex pcr in children with acute non-bloody diarrhea in guatemala. | entamoeba histolytica is believed to be a ubiquitous cause of pediatric non-bloody diarrhea. using a multiplex pcr assay, we identified stool pathogens in 298 guatemalan children presenting with acute, non-bloody diarrhea. despite a high overall pathogen burden, we identified no cases of e. histolytica. knowledge of local epidemiology is important to inform e. histolytica therapeutic strategies in low-income settings. | 2017 | 28858041 |
| antiprotozoal activity of extracts of elaeodendron trichotomum (celastraceae). | chagas disease, amebiasis, giardiasis and trichomoniasis represent a serious health problem in latin america. the drugs employed to treat these illnesses produce important side effects and resistant strains have appeared. the present study was aimed to evaluate the antiprotozoal activity of leaves, stem bark and root bark of elaeodendron trichotomum, a celastraceus, that is used in mexico as an anti-infective in febrile-type diseases. | 2016 | 28852732 |
| inhibition of amebic lysosomal acidification blocks amebic trogocytosis and cell killing. | entamoeba histolytica ingests fragments of live host cells in a nibbling-like process termed amebic trogocytosis. amebic trogocytosis is required for cell killing and contributes to tissue invasion, which is a hallmark of invasive amebic colitis. work done prior to the discovery of amebic trogocytosis showed that acid vesicles are required for amebic cytotoxicity. in the present study, we show that acidified lysosomes are required for amebic trogocytosis and cell killing. interference with lysos ... | 2017 | 28851845 |
| synthetic analogs of an entamoeba histolytica glycolipid designed to combat intracellular leishmania infection. | intracellular pathogens belonging to the genus leishmania have developed effective strategies that enable them to survive within host immune cells. immunostimulatory compounds that counteract such immunological escape mechanisms represent promising treatment options for diseases. here, we demonstrate that a lipopeptidephosphoglycan (lppg) isolated from the membrane of a protozoan parasite, entamoeba histolytica (eh), shows considerable immunostimulatory effects targeted against leishmania (l.) m ... | 2017 | 28842620 |
| the macrophage cytoskeleton acts as a contact sensor upon interaction with entamoeba histolytica to trigger il-1β secretion. | entamoeba histolytica (eh) is the causative agent of amebiasis, one of the major causes of dysentery-related morbidity worldwide. recent studies have underlined the importance of the intercellular junction between eh and host cells as a determinant in the pathogenesis of amebiasis. despite the fact that direct contact and ligation between eh surface gal-lectin and ehcp-a5 with macrophage α5β1 integrin are absolute requirements for nlrp3 inflammasome activation and il-1β release, many other undef ... | 2017 | 28837696 |
| bioflow: a non-invasive, image-based method to measure speed, pressure and forces inside living cells. | cell motility is governed by a complex molecular machinery that converts physico-chemical cues into whole-cell movement. understanding the underlying biophysical mechanisms requires the ability to measure physical quantities inside the cell in a simple, reproducible and preferably non-invasive manner. to this end, we developed bioflow, a computational mechano-imaging method and associated software able to extract intracellular measurements including pressure, forces and velocity everywhere insid ... | 2017 | 28835648 |
| in vitro testing of potential entamoeba histolytica pyruvate phosphate dikinase inhibitors. | adverse effects and resistance to metronidazole have motivated the search for new antiamoebic agents against entamoeba histolytica. control of amoeba growth may be achieved by inhibiting the function of the glycolytic enzyme and pyruvate phosphate dikinase (ppdk). in this study, we screened 10 compounds using an in vitro ppdk enzyme assay. these compounds were selected from a virtual screening of compounds in the national cancer institute database. the antiamoebic activity of the selected compou ... | 2017 | 28820699 |
| microbiome-mediated neutrophil recruitment via cxcr2 and protection from amebic colitis. | the disease severity of entamoeba histolytica infection ranges from asymptomatic to life-threatening. recent human and animal data implicate the gut microbiome as a modifier of e. histolytica virulence. here we have explored the association of the microbiome with susceptibility to amebiasis in infants and in the mouse model of amebic colitis. dysbiosis occurred symptomatic e. histolytica infection in children, as evidenced by a lower shannon diversity index of the gut microbiota. to test if dysb ... | 2017 | 28817707 |
| outbreak of intestinal amoebiasis among men who have sex with men, barcelona (spain), october 2016 and january 2017. | entamoeba histolytica has been recently recognised as an emerging sexually transmissible pathogen in men who have sex with men (msm), causing sporadic outbreaks in countries where it is not endemic. here we report two closed clusters of invasive amoebiasis occurring in barcelona, spain, in october 2016 (four cases) and in january 2017 (four cases). | 2017 | 28797327 |
| different behavior of myeloperoxidase in two rodent amoebic liver abscess models. | the protozoan entamoeba histolytica is the etiological agent of amoebiasis, which can spread to the liver and form amoebic liver abscesses. histological studies conducted with resistant and susceptible models of amoebic liver abscesses (alas) have established that neutrophils are the first cells to contact invasive amoebae at the lesion site. myeloperoxidase is the most abundant enzyme secreted by neutrophils. it uses hydrogen peroxide secreted by the same cells to oxidize chloride ions and prod ... | 2017 | 28796788 |
| larrea tridentata: a novel source for anti-parasitic agents active against entamoeba histolytica, giardia lamblia and naegleria fowleri. | protozoan parasites infect and kill millions of people worldwide every year, particularly in developing countries where access to clean fresh water is limited. among the most common are intestinal parasites, including giardia lamblia and entamoeba histolytica. these parasites wreak havoc on the epithelium lining the small intestines (g. lamblia) and colon (e. histolytica) causing giardiasis and amebiasis, respectively. in addition, there are less common but far more deadly pathogens such as naeg ... | 2017 | 28793307 |
| crystal structure of the peg-bound sh3 domain of myosin ib from entamoeba histolytica reveals its mode of ligand recognition. | the versatility in the recognition of various interacting proteins by the sh3 domain drives a variety of cellular functions. here, the crystal structure of the c-terminal sh3 domain of myosin ib from entamoeba histolytica (ehmysh3) is reported at a resolution of 1.7 å in native and peg-bound states. comparisons with other structures indicated that the peg molecules occupy protein-protein interaction pockets similar to those occupied by the peptides in other peptide-bound sh3-domain structures. a ... | 2017 | 28777082 |
| a unique case of empyema secondary to amoebic liver abscess. | an amoebic liver abscess is an extraintestinal manifestation of amoebiasis that can present with complaints such as right upper quadrant pain and fever. it might not necessarily be associated with abdominal complaints and can have many other atypical presentations. it may present with lung diseases, cardiac diseases, or brain abscesses. we present a case of a patient with empyema secondary to amoebic liver abscess whose diagnosis was delayed due to an unusual presentation. a combination of radio ... | 2017 | 28775917 |
| differential expression of pathogenic genes of entamoeba histolytica vs e. dispar in a model of infection using human liver tissue explants. | we sought to establish an ex vivo model for examining the interaction of e. histolytica with human tissue, using precision-cut liver slices (pcls) from donated organs. e. histolytica- or e. dispar-infected pcls were analyzed at different post-infection times (0, 1, 3, 24 and 48 h) to evaluate the relation between tissue damage and the expression of genes associated with three factors: a) parasite survival (peroxiredoxin, superoxide dismutase and 70 kda heat shock protein), b) parasite virulence ... | 2017 | 28771523 |
| agc family kinase 1 participates in trogocytosis but not in phagocytosis in entamoeba histolytica. | the protozoan parasite entamoeba histolytica is the aetiologic agent of amoebiasis, an endemic infection in developing countries with considerable morbidity and mortality. recently, trogocytosis has been recognized as the key step in amoebic cytolysis and invasion, a paradigm shift in understanding pathogenicity of this organism. here we report that agc family kinase 1 is specifically involved in trogocytosis of live human cells and does not participate in phagocytosis of dead cells. live imagin ... | 2017 | 28740237 |
| investigation of pyrophosphate versus atp substrate selection in the entamoeba histolytica acetate kinase. | acetate kinase (ack; e.c. 2.7.2.1), which catalyzes the interconversion of acetate and acetyl phosphate, is nearly ubiquitous in bacteria but is present only in one genus of archaea and certain eukaryotic microbes. all acks utilize atp/adp as the phosphoryl donor/acceptor in the respective directions of the reaction (acetate + atp [formula: see text] acetyl phosphate + adp), with the exception of the entamoeba histolytica ack (ehack) which uses pyrophosphate (ppi)/inorganic phosphate (pi) (acety ... | 2017 | 28724909 |
| occult amoebic liver abscess as cause of extensive inferior vena cava and hepatic vein thrombosis. | the most common extraintestinal complication of entamoeba histolytica is amoebic liver abscess (ala). hepatic vein and inferior vena cava (ivc) thrombosis are rare but well-documented complications of ala, typically attributed to mechanical compression and inflammation associated with a large abscess. we present a case of a previously healthy 43-year-old canadian man presenting with constitutional symptoms and right upper quadrant abdominal pain. he was found to have thrombophlebitis of the ivc, ... | 2017 | 28722597 |
| case report: endemic amebiasis in australia: implications for residents, travelers, and clinicians. | entamoeba histolytica is considered endemic in australia; however, cases are rare, occurring almost exclusively in high-risk individuals. we describe a series of locally acquired, complicated cases in low-risk individuals from far north queensland in whom the diagnosis was delayed. amebiasis may pose a greater local threat than is currently recognized. | 2017 | 28719303 |
| x-ray snapshots of a pyridoxal enzyme: a catalytic mechanism involving concerted [1,5]-hydrogen sigmatropy in methionine γ-lyase. | pyridoxal 5'-phosphate (plp)-enzymes are essentially involved in amino acid and amine metabolism of a wide variety of organisms. despite their extensive biochemical studies, there are little evidence and structural data to comprehensively elaborate the catalytic mechanism. we obtained x-ray snapshots of l-methionine γ-lyase from entamoeba histolytica (ehmgl), a plp-enzyme catalyzing the γ-elimination reaction of methionine. here, we suggest a catalytic mechanism of ehmgl by using the x-ray snaps ... | 2017 | 28687762 |
| in-silico prediction and modeling of the entamoeba histolytica proteins: serine-rich entamoeba histolytica protein and 29 kda cysteine-rich protease. | amoebiasis is the third most common parasitic cause of morbidity and mortality, particularly in countries with poor hygienic settings. there exists an ambiguity in the diagnosis of amoebiasis, and hence there arises a necessity for a better diagnostic approach. serine-rich entamoeba histolyticaprotein (srehp), peroxiredoxin and gal/galnac lectin are pivotal in e. histolyticavirulence and are extensively studied as diagnostic and vaccine targets. for elucidating the cellular function of these pro ... | 2017 | 28674640 |
| adherens junctions and desmosomes are damaged by entamoeba histolytica: participation of ehcpadh complex and ehcp112 protease. | entamoeba histolytica trophozoites adhere to epithelium at the cell-cell contact and perturb tight junctions disturbing the transepithelial electrical resistance. behind tight junctions are the adherens junctions (ajs) that reinforce them and the desmosomes (dsms) that maintain the epithelium integrity. the damage produced to ajs and dmss by this parasite is unknown. here, we studied the effect of the trophozoites, the ehcpadh complex, and the ehcp112 recombinant enzyme (rehcp112) on aj and dsm ... | 2017 | 28656597 |
| multiplex pcr gastro-intestinal panels for the management of traveller's diarrhea : are they accurate and useful? | until recently, the search for enteropathogens causing travellers' diarrhea was based on stool culture (campylobacter spp., salmonella spp. and shigella spp.), direct microscopy with (cryptosporidium spp.) or without specific staining (giardia lamblia, entamoeba histolytica) or specific antigen detection (giardia lamblia, entamoeba histolytica). molecular analyses are progressively replacing traditional diagnostic methods but their clinical usefulness remains to be better defined. this article a ... | 2017 | 28627855 |
| enteric multiplex pcr panels: a new diagnostic tool for amoebic liver abscess? | invasive amoebiasis is a life-threatening infection requiring immediate detection and treatment. however, diagnosis is challenging because conventional methods such as light microscopy and serology are unreliable. molecular techniques are therefore considered the new diagnostic reference standard, but most of the developed assays are research tools and not widely available. recently commercial multiplex pcr panels have been introduced which permit the simultaneous detection of multiple enteric p ... | 2017 | 28626584 |
| antiamoebic activity of petiveria alliacea leaves and their main component, isoarborinol. | petiveria alliacea l. (phytolacaceae) is a medicinal plant with a broad range of traditional therapeutic properties, including the treatment of dysentery and intestinal infections caused by protozoan parasites. however, its effects against entamoeba histolytica have not been reported yet. we investigated the antiamoebic activity present in the leaves of p. alliacea antiamoebic activity was evaluated in methanolic and aqueous extracts, as well as in the hexanic, methanolic, and etoac fractions. t ... | 2017 | 28621111 |
| intestinal parasitic infestation among paediatric diarrhoea patients attending hospitals in port blair, andaman and nicobar islands. | acute childhood diarrhoea remains one of the leading causes of childhood morbidity and mortality in developing countries. the present study was conducted to estimate the prevalence of various intestinal parasitic infestation among children aged 5 years and less suffering from acute diarrhoea disease attending hospitals in andaman islands. during the period from january 2012 to december 2013, a total of 675 acute diarrhoea patients were included in the study. among these samples, 476 (70.5, 95 % ... | 2017 | 28615884 |
| heavy subunit of cell surface gal/galnac lectin (hgl) undergoes degradation via endo-lysosomal compartments in entamoeba histolytica. | the human gut parasite entamoeba histolytica uses a multifunctional virulence factor, hgl, a cell surface transmembrane receptor subunit of gal/galnac lectin that contributes to adhesion, invasion, cytotoxicity and immune response in the host. at present, the physiologic importance of hgl receptor is mostly known for pathogenicity of e. histolytica. however, the molecular mechanisms of hgl trafficking events and their association with the intracellular membrane transport machinery are largely un ... | 2017 | 28613117 |
| entamoeba histolytica infection in female sex workers: a matched case-control study in durango, mexico. | infection with entamoeba histolytica (e. histolytica) can be potentially transmitted by sexual contact. the seroepidemiology of e. histolytica in female sex workers has not been studied. the aim of the study was to determine whether e. histolytica is associated with the occupation of female sex work. in addition, the correlates of e. histolytica seroprevalence in female sex workers were also investigated. | 2017 | 28611864 |
| investigation of a food-borne outbreak of gastroenteritis in a school canteen revealed a variant of sapovirus genogroup v not detected by standard pcr, sollentuna, sweden, 2016. | a food-borne outbreak of gastroenteritis with more than 650 suspected cases occurred in april 2016 in sollentuna, sweden. it originated in a school kitchen serving a total of 2,700 meals daily. initial microbiological testing (for campylobacter, salmonella, shigella, yersinia, giardia, cryptosporidium, entamoeba histolytica, adeno-, astro-, noro-, rota- and sapovirus) of stool samples from 15 symptomatic cases was negative, despite a clinical presentation suggestive of calicivirus. analyses of t ... | 2017 | 28602163 |
| synthesis, antiprotozoal activity, and chemoinformatic analysis of 2-(methylthio)-1h-benzimidazole-5-carboxamide derivatives: identification of new selective giardicidal and trichomonicidal compounds. | a series of twelve new 2-(methylthio)-1h-benzimidazole-5-carboxamide derivatives (1-12) were synthesized and their antiparasitic activity was tested in vitro against giardia intestinalis, trichomonas vaginalis and entamoeba histolytica. experimental evaluations showed ic50 values within the nanomolar range for all tested compounds, some showing higher activity than metronidazole and albendazole. a chemoinformatic study was used to compare the structure-activity relationship of the synthesized ca ... | 2017 | 28595066 |
| identification of s-nitrosylated (sno) proteins in entamoeba histolytica adapted to nitrosative stress: insights into the role of sno actin and in vitro virulence. | we have recently reported that entamoeba histolytica trophozoites can adapt to toxic levels of the nitric oxide (no) donor, s-nitrosoglutathione (gsno). even if the consequences of this adaptation on the modulation of gene expression in no-adapted trophozoites (nat) have been previously explored, insight on s-nitrosylated (sno) proteins in nat is missing. our study aims to fill this knowledge gap by performing a screening of sno proteins in nat. employing sno resin-assisted capture (rac), we ide ... | 2017 | 28589096 |
| antiprotozoal activities of tiliroside and other compounds from sphaeralcea angustifolia (cav.) g. don. | sphaeralcea angustifolia (malvaceae) is extensively used in mexican traditional medicine for the treatment of gastrointestinal disorders such as diarrhea and dysentery. | 2017 | 28539736 |
| parallel elisas using crude soluble antigen and excretory-secretory antigen for improved serodiagnosis of amoebic liver abscess. | crude soluble antigen (csa) produced from entamoeba histolytica trophozoite is conventionally used for serodiagnosis of invasive amoebiasis. however, high background seropositivities by csa-assay in endemic areas complicate the interpretation of positive result in clinical settings. instead, incorporating a second assay which indicates active or recent infection into the routine amoebic serology could possibly complement the limitations of csa-assay. hence, the present study aimed to evaluate th ... | 2017 | 28506795 |
| structure of ca2+-binding protein-6 from entamoeba histolytica and its involvement in trophozoite proliferation regulation. | cell cycle of entamoeba histolytica, the etiological agent of amoebiasis, follows a novel pathway, which includes nuclear division without the nuclear membrane disassembly. we report a nuclear localized ca2+-binding protein from e. histolytica (abbreviated hereafter as ehcabp6), which is associated with microtubules. we determined the 3d solution nmr structure of ehcabp6, and identified one unusual, one canonical and two non-canonical cryptic ef-hand motifs. the cryptic ef-ii and ef-iv pair with ... | 2017 | 28505197 |
| crystal structure of the entamoeba histolytica rna lariat debranching enzyme ehdbr1 reveals a catalytic zn(2+) /mn(2+) heterobinucleation. | the rna lariat debranching enzyme, dbr1, is a metallophosphoesterase that cleaves 2'-5' phosphodiester bonds within intronic lariats. previous reports have indicated that dbr1 enzymatic activity is supported by diverse metal ions including ni(2+) , mn(2+) , mg(2+) , fe(2+) , and zn(2+) . while in initial structures of the entamoeba histolytica dbr1 only one of the two catalytic metal-binding sites were observed to be occupied (with a mn(2+) ion), recent structures determined a zn(2+) /fe(2+) het ... | 2017 | 28504306 |
| the e. histolytica genome structure and virulence. | the outcome of an entamoeba histolytica infection is variable and the contribution of genetic diversity within e. histolytica to human disease is not fully understood. the information provided by the whole genome sequence of the e. histolytica reference laboratory strain (hm-1:imss) and thirteen additional laboratory strains have been made publically available. in this review theories on the source of the unexpected level of structural diversity found in e. histolytica will be discussed. | 2016 | 28497014 |
| treatment of diarrhoea using traditional medicines: contemporary research in south africa and zimbabwe. | gastrointestinal disorders, diarrhoea in particular remain a major concern in south africa and zimbabwe resulting in high mortality rates when left untreated. this investigation was aimed at documenting herbal medicines used in the treatment of diarrhoea in south africa and zimbabwe. | 2016 | 28480353 |
| ehrho1 regulates plasma membrane blebbing through pi3 kinase in entamoeba histolytica. | the protozoan parasite entamoeba histolytica causes amoebiasis, a major public health problem in developing countries. motility of e. histolytica is important for its pathogenesis. blebbing is an essential process contributing to cellular motility in many systems. in mammalian cells, formation of plasma membrane blebs is regulated by rho-gtpases through its effectors, such as rho kinase, mdia1, and acto-myosin proteins. in this study, we have illuminated the role of ehrho1 in bleb formation and ... | 2017 | 28477431 |
| an anti-amoebic vaccine: generation of the recombinant antigen lc3 from entamoeba histolytica linked to mutated exotoxin a (peδiii) via the pichia pastoris system. | to generate an immunogenic chimeric protein containing the entamoeba histolytica lc3 fragment fused to the retrograde delivery domains of exotoxin a of pseudomonas aeruginosa and kdel3 for use as an effective vaccine. | 2017 | 28470625 |
| proliferating cell nuclear antigen restores the enzymatic activity of a dna ligase i deficient in dna binding. | proliferating cell nuclear antigen (pcna) coordinates multienzymatic reactions by interacting with a variety of protein partners. family i dna ligases are multidomain proteins involved in sealing of dna nicks during okazaki fragment maturation and dna repair. the interaction of dna ligases with the interdomain connector loop (idcl) of pcna through its pcna-interacting peptide (pip box) is well studied but the role of the interacting surface between both proteins is not well characterized. in thi ... | 2017 | 28469979 |
| entamoeba histolytica: host parasite interactions at the colonic epithelium. | entamoeba histolytica (eh) is the protozoan parasite responsible for intestinal amebiasis and interacts dynamically with the host intestinal epithelium during disease pathogenesis. a multifaceted pathogenesis profile accounts for why 90% of individuals infected with eh are largely asymptomatic. for 100 millions individuals that are infected each year, key interactions within the intestinal mucosa dictate disease susceptibility. the ability for eh to induce amebic colitis and disseminate into ext ... | 2017 | 28452682 |
| prevalence of parasitic contamination in salad vegetables collected from supermarkets and street vendors in amman and baqa’a - jordan. | one of the main ways in transmitting parasites to humans is through consuming contaminated raw vegetables. the aim of this study was to evaluate the prevalence of parasitological contamination (helminthes eggs, giardia and entamoeba histolytica cysts) of salad vegetables sold at supermarkets and street vendors in amman and baqa’a – jordan. a total of 133 samples of salad vegetables were collected and examined for the prevalence of parasites. it was found that 29% of the samples were contaminated ... | 2016 | 28517923 |