|
|
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,...
|
|
|
Population differences in the distribution of HLA-B27 allele in ankylosing spondylitis
Lennerová, Tereza ; Hušáková, Markéta (advisor) ; Novota, Peter (referee)
Ankylosing spondylitis (AS) is a chronic inflammatory disease affecting mainly the spine and the sacroiliac joints. This disorder has a genetic background and is strongly associated with HLA-B27 gene which occurs in about 90 % of patients. The prevalence of ankylosing spondylitis usually correlates with the frequency of HLA-B27. The strength of association HLA-B27 with AS varies between different populations and is also distinct for individual alleles of HLA-B27 gene. Some alleles can increase a risk of ankylosing spondylitis while others may have a protective effect. This work deals with the population differences in the occurrence of HLA-B27 alleles and their relation to development of ankylosing spondylitis. Key words: ankylosing spondylitis, HLA-B27, allele, subtype, population differences
|
|
| |
|
|
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,...
|
|
|
Population differences in the distribution of HLA-B27 allele in ankylosing spondylitis
Lennerová, Tereza ; Hušáková, Markéta (advisor) ; Novota, Peter (referee)
Ankylosing spondylitis (AS) is a chronic inflammatory disease affecting mainly the spine and the sacroiliac joints. This disorder has a genetic background and is strongly associated with HLA-B27 gene which occurs in about 90 % of patients. The prevalence of ankylosing spondylitis usually correlates with the frequency of HLA-B27. The strength of association HLA-B27 with AS varies between different populations and is also distinct for individual alleles of HLA-B27 gene. Some alleles can increase a risk of ankylosing spondylitis while others may have a protective effect. This work deals with the population differences in the occurrence of HLA-B27 alleles and their relation to development of ankylosing spondylitis. Key words: ankylosing spondylitis, HLA-B27, allele, subtype, population differences
|
|
|
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.
|
guest ::
