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Studium prevalence a subtypové diverzity střevního prvoka rodu Blastocystis sp. ve zdravé lidské populaci v České republice
BROŽOVÁ, Kristýna
Blastocystis sp. is a common intestinal protist colonizing the human intestine. Its role in the human gut ecosystem remains unclear. Here, we aimed to expand the knowledge of the epidemiology of Blastocystis sp. in the gut-healthy humans in the Czech Republic, including the distribution of its subtypes, the correlation between its occurrence and several factors such as lifestyle, contact with animals, age, and sex. A total of 288 stool samples were obtained from asymptomatic individuals over the entire age-range and 136 samples from animals with which the volunteers were in frequent contact. All samples were examined in parallel by PCR and xenic in vitro culture.
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Diversity of Blastocystis (Stramenopiles) in reptiles and arthropods
Lorencová, Markéta ; Čepička, Ivan (advisor) ; Jirků, Kateřina (referee)
The genus Blastocystis has recently attracted the attention of scientists, especially parasitologists. Similarly to the related opalines and proteromonads, Blastocystis is anaerobic and lives endobiotically in the intestine of various animals. This organism is also often found in humans, where it is associated with irritable bowel syndrome, though its pathogenic potential remains uncertain. The genus Blastocystis is remarkable for its rich genetic diversity. The taxonomy of Blastocystis is inconsistent and problematic. The strains isolated from homoiothermic vertebrates are divided into 17 subtypes, while strains from poikilotherms are either classified as separate species or are not considered in taxonomic studies at all. The aim of the study was to further examine the genetic diversity of the genus Blastocystis. We determined SSU rDNA sequences of 38 strains isolated from poikilothermic vertebrates and arthropods. The results of our phylogenetic analysis showed that Blastocystis is considerably diverse in these hosts, and we defined 21 new subtypes. The total number of known subtypes of Blastocystis has thus increased to 38. We also examined light-microscopical morphology of some strains. Most of the newly defined subtypes show identical morphology, ST20 (Blastocystis geocheloni) is an exception,...
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Diversity of Blastocystis (Stramenopiles) in reptiles and arthropods
Lorencová, Markéta ; Čepička, Ivan (advisor) ; Jirků, Kateřina (referee)
The genus Blastocystis has recently attracted the attention of scientists, especially parasitologists. Similarly to the related opalines and proteromonads, Blastocystis is anaerobic and lives endobiotically in the intestine of various animals. This organism is also often found in humans, where it is associated with irritable bowel syndrome, though its pathogenic potential remains uncertain. The genus Blastocystis is remarkable for its rich genetic diversity. The taxonomy of Blastocystis is inconsistent and problematic. The strains isolated from homoiothermic vertebrates are divided into 17 subtypes, while strains from poikilotherms are either classified as separate species or are not considered in taxonomic studies at all. The aim of the study was to further examine the genetic diversity of the genus Blastocystis. We determined SSU rDNA sequences of 38 strains isolated from poikilothermic vertebrates and arthropods. The results of our phylogenetic analysis showed that Blastocystis is considerably diverse in these hosts, and we defined 21 new subtypes. The total number of known subtypes of Blastocystis has thus increased to 38. We also examined light-microscopical morphology of some strains. Most of the newly defined subtypes show identical morphology, ST20 (Blastocystis geocheloni) is an exception,...
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Diversity of the genus Blastocystis (Stramenopiles)
Lorencová, Markéta ; Čepička, Ivan (advisor) ; Kostka, Martin (referee)
Although the genus Blastocystis is only little known, it has recently attracted much attention of protistologists and parasitologists. Similarly to the related opalines and proteromonads, Blastocystis is anaerobic and lives endobiotically in intestines of many animals. On the other hand, members of the genus have completely lost flagella. Therefore, the phylogenetic position of Blastocystis had been puzzling for a long time. B. hominis is one of the most common intestinal parasites of humans and has been found also in a wide variety of animals. It is highly prevalent not only in the developing nations, but also in the developed countries. Its enormous genetic diversity, pathogenic and zoonotic potential (B. hominis is often associated with irritable bowel syndrome) make from B. hominis an important emerging pathogen.
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Blastocystis subtypes in pigs
LAKATOSOVÁ, Lucie
Blastocystis is an anaerobic single-celled protozoan that commonly occurs in the intestinal tract of animals and humans. It is a genetically very variable organism. Blastocystis can be found both in healthy specimens and in patients with gastrointestinal disorders. In 2011/2012, I examinated already isolated DNA samples from domestic and wild pigs by molecular methods in the laboratory of the ASCR Parasitology Institute. In total, 110 samples were examined. The domestic pigs were positive in 91 % (51/56) and wild pigs in 67 % (36/54). The overall prevalence of domestic pigs was higher by 24 %. Several sequences of SSU rRNA gene obtained during the work suggest that pigs may serve as host for atypical Blastocystis subtypes.
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Blastocystis in domestic birds
HRDLIČKOVÁ, Jaroslava
During 2010, faeces samples for parasitology research oriented on Blastocystis were collected from an anonymous farm. A total of 55 samples were collected (of them for 10 faeces samples from hens, ducks and geese and 25 from pigeons). The samples were cultured in Dobell-Leidlaw medium and viewed by light microscopy. However, this method led to only two foundings of Blastocystis (one from hen, the other from pigeon). Thus, PCR and nested-PCR with specific primers were later used for better detection of Blastocystis. The samples for PCR detection were not collected from the aforementioned farm, but they originated from a collection of isolated DNA samples that was available on the Parasitology institute of AS CR. The results of PCR were checked after electrophoresis and verified by sequenation. The obtained sequences of bird-isolated Blastocystis were phylogenetically analysed and as described to subtype 7.
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Blastocystis in pigs
HORSKÁ, Ivana
Blastocystis is an obligately anaerobic protist, commonly found in intestinal tract of numerous animals and humans across whole world. It is genetically very variable and rather enigmatic organism. Many aspects of its biology need to be further studied and clarified. On a chosen farm were during the year 2010 collected samples of pig faeces for parasitological survey. A total number of 40 samples was collected and cultivated by the method of Dobel-Leidlaw (1926). Of them, 19 was positive for Blastocystis. Other samples were checked by molecular methods (PCR). Using them, five Blastocystis sequences were obtained, which clearly belong to subtypes 1 and 5.
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Blastocystis in pigs
LAKATOSOVÁ, Lucie
The genus Blastocystis belongs among anaerobic unicellular, polymorphic organisms living in intestinal tract of many invertebrates and vertebrates including humans. Genetic variability and spectrum of hosts of this protist is tremendous. Several subtypes exist that are able to inhabit intestine of specific hosts. For example, the subtype 3 is probably the only human-borne subtype and is therefore most often isolated human subtype. It not clear how many species of Blastocystis exist. Anyway, the best known one is B. hominis isolated from humans. It is possible that Blastocystis is responsible for some diseases. It can be found in both healthy individuals and patients with gastrointestinal disorders. The Blastocystis infection can spread easily via orally transmitted cysts. Blastocystis is commonly found in epidemiological studies. During the year 2009/2010 I collected samples in the breeding and production facilities of a pig farm from different categories (bred or auction sows and boars, female barren, gravid, suckling, and one bred boar). A total of 46 samples was cultivated using two-phase media (Dobell Leidlaw).In most specimens I found Blastocystis and, to a lesser extent, trichomonads.
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