Search results for "Blastocystis Infections"
showing 10 items of 10 documents
Prevalence of intestinal parasites, with emphasis on the molecular epidemiology of Giardia duodenalis and Blastocystis sp., in the Paranaguá Bay, Bra…
2018
BACKGROUND: Intestinal protozoan parasites are major contributors to the global burden of gastrointestinal disease causing significant socioeconomic consequences. Children living in resource-poor settings with restricted access to water and sanitary services are particularly at risk of these infections. METHODS: A prospective, community-based, cross-sectional survey was conducted in Paraná (southern Brazil) between May 2015 and May 2016. A total of 766 stool samples were individually collected from volunteers (male/female ratio: 0.99; age range: 0-76 years) and used for investigating the presence of intestinal helminth and protozoan species by routine microscopic procedures including the Ka…
Blastocystis subtypes and their association with Irritable Bowel Syndrome.
2018
Blastocystis spp. is a common intestinal protozoan that affects humans and animals. The role of this parasite as a pathogen is still controversial and it is suspected to be linked to Irritable Bowel Syndrome (IBS), a functional bowel disorder characterized by chronic or recurrent abdominal pain associated with altered intestinal habits. A broad search in electronic databases, libraries, portals of journals, etc. for reports on the association between the parasite and IBS without language restriction was performed. The selection was not restricted by date, but articles published in the last seven years were given preference. We investigated the evidence regarding Blastocystis and IBS coexist…
Efficient and reproducible experimental infections of rats with Blastocystis spp.
2018
Although Blastocystis spp. infect probably more than 1 billion people worldwide, their clinical significance is still controversial and their pathophysiology remains poorly understood. In this study, we describe a protocol for an efficient and reproducible model of chronic infection in rats, laying the groundwork for future work to evaluate the pathogenic potential of this parasite. In our experimental conditions, we were unable to infect rats using vacuolar forms of an axenically cultivated ST4 isolate, but we successfully established chronic infections of 4 week-old rats after oral administration of both ST3 and ST4 purified cysts isolated from human stool samples. The infection protocol …
Soluble-protein and antigenic heterogeneity in axenic Blastocystis hominis isolates: pathogenic implications.
1999
The protein profile and the antigenic cross-reactivity of 18 axenic isolates of Blastocystis hominis obtained from symptomatic patients with chronic diarrhea (14 isolates) showing no evidence of parasitic etiology and from patients with acute diarrhea attributable in 2 cases to Salmonella spp. were analyzed. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of soluble proteins showed the existence of a common profile composed of 31 bands, with molecular weights ranging between 24 and >200 kDa, and minor differences in the proteins of 149, 118, 106, 50, 48, 47, and 30 kDa. These differences allowed us to classify the strains into three related patterns (I–III). In an indirect immunof…
Variable geographic distribution of Blastocystis subtypes and its potential implications.
2012
Blastocystis is a common intestinal micro-eukaryote found in both humans and non-human hosts and known to be genetically very diverse. It has been divided into numerous subtypes (STs), nine of which have been identified in humans to date. Surveys of ST prevalence have started to emerge over the past few years but to date no data are available for any African country except Egypt and Tanzania. In this study, we determined the prevalence of Blastocystis STs in populations from Libya, Liberia and Nigeria, as well as expanding the dataset available for the UK. A total of 356 Blastocystis STs were identified in this study, 271 from the UK, 38 from Libya, 25 from Liberia and 22 from Nigeria. SSU …
Karyotypic diversity among Blastocystis hominis isolates
1997
Fifteen Blastocystis hominis strains, 13 axenic and 2 monoxenic, have been included in the present study. The chromosomal pattern was analyzed by the contour-clamped homogeneous electric-field (CHEF) system. The number of chromosomes detected ranged between 9 and 13, with sizes from 2200 kbp to 260 kbp. Eleven karyotypic profiles, with a common pattern constituted by 8 chromosomes of 2200, 1280, 890, 840, 700, 650, 540 and 260 kbp, were observed. The Jaccard index demonstrated that the similarity between isolates ranged from 0.5714 to 1. The different isolates were clustered in 3 karyotypes (A: 8 isolates; B: 6 isolates and C: 1 isolate). All isolates grouped in karyotype A presented a char…
Presence of Blastocystis in gut microbiota is associated with cognitive traits and decreased executive function.
2022
Growing evidence implicates the gut microbiome in cognition. Blastocystis is a common gut single-cell eukaryote parasite frequently detected in humans but its potential involvement in human pathophysiology has been poorly characterized. Here we describe how the presence of Blastocystis in the gut microbiome was associated with deficits in executive function and altered gut bacterial composition in a discovery (n = 114) and replication cohorts (n = 942). We also found that Blastocystis was linked to bacterial functions related to aromatic amino acids metabolism and folate-mediated pyrimidine and one-carbon metabolism. Blastocystis-associated shifts in bacterial functionality translated into …
Intestinal symptoms and Blastocystis load in schoolchildren of Paranaguá Bay, Paraná, Brazil
2017
ABSTRACT The symptomatology of Blastocystis cannot be attributed to any particular subtype, although can be related to a high Blastocystis infection load. One stool sample from each of 217 schoolchildren of Vale de Sol Paranaguá Bay (Paraná, Brazil) was collected. Three milliliters of each fixed stool sample were processed applying the formalin-ether concentration technique. After obtaining the overall prevalence of intestinal parasites, quantification was carried out in Blastocystis positive samples. A total of 75/217 (34.6%) children suffered from intestinal symptoms (abdominal pain and/or persistent diarrhea), of whom 41.3% (31/75) presented moderate/heavy Blastocystis load with a statis…
High prevalence of Blastocystis sp. in pigs reared under intensive growing systems: Frequency of ribotypes and associated risk factors
2007
Three hundred and ninety-five pig fecal samples were analyzed looking for Blastocystis sp. using optical microscopy and PCR. A global prevalence of 46.8% has been observed in this study, although relative values of prevalence differ notably according to the strata examined, ranging from 9.3% in sows to 75% in weaners. Statistic analysis of the data included several risk factors such as different management systems, date of sample collection, fecal consistency, age and sex of the animals. The presence of the parasite was statistically associated to the variables "age" and "date of sample collection", being more prevalent in weaners and grower pigs and warm season. Random fragment-length poly…
Description of an improved method for Blastocystis hominis culture and axenization
1996
An improved method for Blastocystis hominis culture and axenization was developed in the present study. Stool samples were cultured in prereduced Boeck-Drbohlav NHI modified medium (with several modifications) supplemented with antibiotics (0.4% ampicillin, 0.1% streptomycin, 0.0006% amphotericin B). Axenization was performed by the combination of partial purification of B. hominis by Ficoll-metrizoic acid gradient and inoculation in fresh medium containing active antibiotics against remaining bacteria. A total of 25 strains were obtained by this procedure. The time required for axenization ranged between 3 and 5 weeks. The generation time of axenic strains ranged from 6.6 to 12.1 h (mean +…