Entamoeba histolytica: a snapshot of current research and methods for genetic analysis

Morf, Laura; Singh, Upinder

doi:10.1016/j.mib.2012.04.011

Cited by 25 publications

(22 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Entamoeba spp. are human pathogens that are transmitted by various forms of contact due to their direct life cycle ( Pedersen et al., 2005 , Berrilli et al., 2011 , Morf and Singh, 2012 ). Although, only E. dispar and E. coli were found in this study (Unpublished data) which were non-pathogenic species with low risk of zoonotic transmission from NHPs to human, the zoonotic transmit also should be pay attention.…”

Section: Discussionmentioning

confidence: 99%

An investigation of parasitic infections and review of molecular characterization of the intestinal protozoa in nonhuman primates in China from 2009 to 2015

Dong

Wang

et al. 2017

International Journal for Parasitology: Parasites and Wildlife

View full text Add to dashboard Cite

Parasites are a well-known threat to nonhuman primate (NHP) populations, and potentially cause zoonotic diseases in humans. In this study, the basic data was provided of the parasites in NHPs and the molecular characterization of the Enterocytozoon bieneusi, Giardia duodenalis, Cryptosporidium spp., and Entamoeba spp. were reviewed, which were found in these samples. A total of 3349 fecal samples were collected from 34 species reared at 17 districts in zoos, farms, free-range, or research laboratories, and examined microscopically. Eleven genera of intestinal parasites were detected: five genera of protozoans (Isospora spp., Entamoeba spp., Giardia sp., Cryptosporidium spp., and Cyclospora spp.) and six genera of helminths (Trichuris spp., Strongyloides spp., Ascaris spp., Physaloptera spp., Ancylostoma spp., and Enterobius spp.). The overall sample prevalence of parasitic infection was 54.1% (1811/3349). Entamoeba spp. was the most prevalent (36.4%, 1218/3349). The infection rate was the highest in free-range animals (73.0%, 670/918) (P < 0.01) and Guangxi Zhuang autonomous region (64.8%, 566/873). Mixed infections were mostly detected for Entamoeba spp., Trichuris spp., and Strongyloides spp.. Molecular characterization was reviewed of Enterocytozoon bieneusi, Giardia duodenalis, Cryptosporidium spp., and Entamoeba spp., as these are zoonotic species or genotypes. This parasitological data for NHPs in China, provides important information for veterinarians and public health authorities for the elimination of such parasites and monitor the potential transmission of zoonotic infections from NHPs.

show abstract

Section: Discussionmentioning

confidence: 99%

An investigation of parasitic infections and review of molecular characterization of the intestinal protozoa in nonhuman primates in China from 2009 to 2015

Dong

Wang

et al. 2017

International Journal for Parasitology: Parasites and Wildlife

View full text Add to dashboard Cite

show abstract

“…The potential effect of malnutrition, immune suppression, or AIDS on treatment is not known. Studies have demonstrated that severity of disease outcomes following E histolytica infection are determined by host susceptibility, which can be dependent on genetic factors or on environmental factors, such as malnutrition, and therefore may vary among different populations and geographical locations (Morfl 2012). Although asymptomatic infection with E histolytica is more common than symptomatic disease, treatment of these individuals remains controversial because most will clear their infection within one year, and only about 3% to 10% will manifest invasive disease (Gathiram 1987; Haque 2001; Haque 2002; Blessman 2003).…”

Section: Discussionmentioning

confidence: 99%

Antiamoebic drugs for treating amoebic colitis

Gonzales

Dans

Sio‐Aguilar

2019

Cochrane Database of Systematic Reviews

View full text Add to dashboard Cite

Background Infection with the protozoan Entamoeba histolytica is common in low‐ and middle‐income countries, and up to 100,000 people with severe disease die every year. Adequate therapy for amoebic colitis is necessary to reduce illness, prevent development of complicated disease and extraintestinal spread, and decrease transmission. Objectives To evaluate antiamoebic drugs for treating amoebic colitis. Search methods We searched the available literature up to 22 March 2018. We searched the Cochrane Infectious Diseases Group Specialised Register, CENTRAL, MEDLINE, Embase, LILACS, m RCT, and conference proceedings. We contacted individual researchers, organizations, and pharmaceutical companies, and we checked reference lists. Selection criteria Randomized controlled trials of antiamoebic drugs given alone or in combination, compared with placebo or another antiamoebic drug, for treating adults and children with a diagnosis of amoebic colitis. Data collection and analysis Two review authors independently assessed the eligibility and methodological quality of trials and extracted and analysed the data. We calculated clinical and parasitological failure rates and rates of relapse and adverse events as risk ratios (RRs) with 95% confidence intervals (CIs), using a random‐effects model. We determined statistical heterogeneity and explored possible sources of heterogeneity using subgroup analyses. We carried out sensitivity analysis by using trial quality to assess the robustness of reported results. Main results In total, 41 trials (4999 participants) met the inclusion criteria of this review. In this update, we added four trials to the 37 trials included in the first published review version. Thirty trials were published over 20 years ago. Only one trial used adequate methods of randomization and allocation concealment, was blinded, and analysed all randomized participants. Only one trial used an E histolytica stool antigen test, and two trials used amoebic culture. Tinidazole may be more effective than metronidazole for reducing clinical failure (RR 0.28, 95% CI 0.15 to 0.51; 477 participants, eight trials; low‐certainty evidence) and is probably associated with fewer adverse events (RR 0.65, 95% CI 0.46 to 0.92; 477 participants, 8 trials; moderate‐certainty evidence). Compared with metronidazole, combination therapy may result in fewer parasitological failures (RR 0.36, 95% CI 0.15 to 0.86; 720 participants, 3 trials; low‐certainty evidence), but we are uncertain which combination is more effective than another. Evidence is insufficient to allow conclusions regarding the efficacy of other antiamoebic drugs. Authors' conclusions Compared with metronidazole, tinidazole may be more effective in reducing clinical failur...

show abstract

“…We look forward to the time when a sixth strategy (targeted knockouts and forward genetics) can be applied to studies of cyst and oocyst walls. This is already the case for tissue cysts of Toxoplasma and may soon be the case for Entamoeba cysts and Eimeria oocysts (56,57,80,(84)(85)(86).…”

Section: Conclusion and Future Strategiesmentioning

confidence: 90%

Strategies To Discover the Structural Components of Cyst and Oocyst Walls

et al. 2013

View full text Add to dashboard Cite

bCysts of Giardia lamblia and Entamoeba histolytica and oocysts of Toxoplasma gondii and Cryptosporidium parvum are the infectious and sometimes diagnostic forms of these parasites. To discover the structural components of cyst and oocyst walls, we have developed strategies based upon a few simple assumptions. Briefly, the most abundant wall proteins are identified by monoclonal antibodies or mass spectrometry. Structural components include a sugar polysaccharide (chitin for Entamoeba, ␤-1,3-linked glucose for Toxoplasma, and ␤-1,3-linked GalNAc for Giardia) and/or acid-fast lipids (Toxoplasma and Cryptosporidium). Because Entamoeba cysts and Toxoplasma oocysts are difficult to obtain, studies of walls of nonhuman pathogens (E. invadens and Eimeria, respectively) accelerate discovery. Biochemical methods to dissect fungal walls work well for cyst and oocyst walls, although the results are often unexpected. For example, echinocandins, which inhibit glucan synthases and kill fungi, arrest the development of oocyst walls and block their release into the intestinal lumen. Candida walls are coated with mannans, while Entamoeba cysts are coated in a dextran-like glucose polymer. Models for cyst and oocyst walls derive from their structural components and organization within the wall. Cyst walls are composed of chitin fibrils and lectins that bind chitin (Entamoeba) or fibrils of the ␤-1,3-GalNAc polymer and lectins that bind the polymer (Giardia). Oocyst walls of Toxoplasma have two distinct layers that resemble those of fungi (␤-1,3-glucan in the inner layer) or mycobacteria (acid-fast lipids in the outer layer). Oocyst walls of Cryptosporidium have a rigid bilayer of acid-fast lipids and inner layer of oocyst wall proteins. Acid-fast lipids, Fibrils of beta-glucan, Dityrosine glows.-Anonymous, Haiku of the oocyst wall I n this minireview, we discuss strategies that have worked well to discover structural components of protist walls that allow them to travel by the fecal-oral route from one person to the next (1-5). Proteins and sugars are the major components of cyst walls of Entamoeba and Giardia, which cause amebic dysentery and diarrhea, respectively (6-8). In addition to proteins and carbohydrates, lipids are important structural components of oocyst walls of Cryptosporidium and Toxoplasma, which cause diarrhea and disseminated infections, respectively (9-11).To characterize the structural components of walls of so many different organisms, we have had to focus on what is likely to matter most. Many of these wall-oriented strategies are based upon a set of assumptions that may not be obvious to investigators working on stages of the parasites that are motile and dividing (12). Therefore, we review here the strategies and assumptions most useful to determine the protein, carbohydrate, and lipid compositions of cyst and oocyst walls. The compositions of these cyst and oocyst walls are then used to make simple, if incomplete, models for their structure and assembly.

show abstract

Entamoeba histolytica: a snapshot of current research and methods for genetic analysis

Cited by 25 publications

References 53 publications

An investigation of parasitic infections and review of molecular characterization of the intestinal protozoa in nonhuman primates in China from 2009 to 2015

An investigation of parasitic infections and review of molecular characterization of the intestinal protozoa in nonhuman primates in China from 2009 to 2015

Antiamoebic drugs for treating amoebic colitis

Strategies To Discover the Structural Components of Cyst and Oocyst Walls

Contact Info

Product

Resources

About