• MeSH
• klinické praxe * MeSH
• nemocnice MeSH
• Geografické názvy
• Portugalsko MeSH

Mice are used most often as a model for human toxocariasis caused by Toxocara canis larvae. Variety of symptoms developing during the infection reflects behaviour of the larvae, which are able to escape from the intestine and further invade and damage various host organs. In order to find an approach enabling observation on parasite behaviour in mouse in vivo, we used an epifluorescence method and a small animal imaging system (SAIS). Larvae of T. canis were labelled by carboxyfluorescein succinimidyl ester (CFSE) which incorporated on the parasite gastrointestinal tract. Following infection of BALB/c mice by CFSE-labelled larvae it has been observed that staining had no influence on viability and further migratory activity of the parasites through the host organs (the intestine, liver, lungs and brain) where they were detected by SAIS until day 17 p.i. In addition, the dye did not affect larval antigenic activity as well as the development of related immune response. Imaging of parasites labelled by CFSE, therefore, may represent a promising way to study behaviour of T. canis larvae in a paratenic host.

• MeSH
• anatomické struktury zvířat parazitologie   MeSH
• barvení a značení MeSH
• časové faktory MeSH
• fluoresceiny metabolismus   MeSH
• fluorescenční barviva metabolismus   MeSH
• modely nemocí na zvířatech MeSH
• myši inbrední BALB C MeSH
• myši MeSH
• nemoci hlodavců parazitologie   MeSH
• sukcinimidy metabolismus   MeSH
• Toxocara canis růst a vývoj   izolace a purifikace   patogenita   MeSH
• toxokaróza parazitologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Toxoplasma gondii, a parasite infecting 20-60% of humans in various countries, influences the behaviour of infected animal and human hosts. Infected human subjects have changes in several of Cattell's and Cloninger's personality factors. Recently, three independent studies have shown that Rh-positive subjects are protected against the T. gondii-induced changes of reaction times and increased risk of traffic accidents. Here we searched for evidence of similar effects of RhD phenotype on toxoplasmosis- or aging-associated changes in the personality profile of about 302 blood donors. We found that Rh-positive and Rh-negative subjects responded differently to toxoplasmosis. In addition to the already known effects of toxoplasmosis on novelty seeking, self transcendence, superego strength and protension, we also found effects of RhD phenotype on ego strength, protension, and praxernia, as well as opposite effects of toxoplasmosis on ego strength, praxernia, ergic tension and cooperativeness in Rh-positive and Rh-negative subjects. Moreover, our results indicate that RhD phenotype might influence not only the effect of toxoplasmosis but also the effect of aging on specific personality traits.

• MeSH
• dospělí MeSH
• financování organizované MeSH
• krevní skupiny - systém Rh-Hr genetika   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• osobnost MeSH
• senioři MeSH
• stárnutí fyziologie   MeSH
• toxoplazmóza psychologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH

Toxoplasma is parasite of cats that uses any warm-blooded animals as intermediate hosts. It is known to induce shifts in behavior, physiology and even morphology of its intermediate hosts, including humans. The lower second to fourth digit ratio (2D:4D ratio) in infected man and women, and higher height in infected man suggest that sex steroid hormones like testosterone could play a role in these shifts. Here, we searched for another indirect indication for a higher postnatal testosterone level, i.e. increased perceived dominance and masculinity in infected men. We showed portrait pictures of 89 male students of which 18 were Toxoplasma-infected to 109 female students. When we statistically corrected for age, men with latent toxoplasmosis were perceived as more dominant (p=0.009) and masculine (p=0.052). These results support the idea that the higher level of testosterone could be responsible for at least some of the toxoplasmosis-associated shifts in human and animal behavior.

• MeSH
• chování MeSH
• dospělí MeSH
• financování organizované MeSH
• lidé MeSH
• percepce MeSH
• sociální dominance MeSH
• testosteron krev   MeSH
• Toxoplasma MeSH
• toxoplazmóza krev   MeSH
• zvířata MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• randomizované kontrolované studie MeSH
• srovnávací studie MeSH

Using a small animal imaging system, migratory activity of Toxocara canis larvae stained by carboxyfluorescein succinimidyl ester (CFSE) was observed post primary infection (PPI) and post reinfection (PR) of BALB/c mice. Each infection was performed with 1,000 larvae per mouse. Primary infections were performed with labeled larvae, while for challenge infections the reinfecting larvae were stained by CFSE. The worm burden in mouse organs was determined during a period from 6 h to 21 days and 4 months PPI and PR. In comparison with primary infections that led to the first larvae appearance in the brain after 60 h, greatly accelerated migration of the parasites administered 3 weeks PPI to the CNS and eyes of challenged mice was noted-in both organs the larvae appeared 6 h PR. In all challenged mice, reinfecting larvae prevailed in the resident parasite population. Preliminary experiments with Toxocara cati larvae also revealed early brain involvement in primarily infected mice. Staining of T. canis larvae by CFSE had no effect on the development of a humoral antibody response against T. canis excretory-secretory antigens. In ELISA, elevated levels of specific IgG and IgG1 were noted on day 14 PPI and the levels of antibodies increased till the end of experiment. Reinfection induced an increase in the levels of both antibodies. In terms of optical density, IgG1 antibodies gave higher values in all sera examined. In ELISA for IgG antibodies, an increase in the avidity index of around 50% was detected 1 month PPI; higher-avidity antibodies were also detected in sera of reinfected animals.

• MeSH
• barvení a značení MeSH
• časové faktory MeSH
• ELISA MeSH
• helmintózy centrálního nervového systému patologie   MeSH
• imunoglobulin G krev   MeSH
• larva patogenita   MeSH
• mozek parazitologie   MeSH
• myši inbrední BALB C MeSH
• myši MeSH
• oči parazitologie   MeSH
• oční nemoci parazitologie   patologie   MeSH
• parazitární zátěž MeSH
• protilátky helmintové krev   MeSH
• Toxocara canis patogenita   MeSH
• toxokaróza parazitologie   patologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The aims of this study were to evaluate seroprevalence and the importance of various risk-factors for Toxoplasma infection in the Czech Republic. A prospective cross-sectional survey was conducted among military personnel in Prague. Consenting subjects (n = 3250) completed a questionnaire concerning demographics and risk-factors, and blood samples were taken to determine anti-Toxoplasma antibody titres according to complement fixation and ELISA IgG and IgM tests. The seroprevalence of toxoplasmosis was 23%. In multivariate analysis, independent predictors of Toxoplasma seropositivity were age (OR 1.03 / year), consumption of raw meat (OR 1.35), owning a cat (OR 1.25), owning rabbits (OR 1.47), childhood residence in a town with a population of <10 000 inhabitants (OR 1.63) vs. location of the childhood residence in a town with population of >100 000 inhabitants, and blood group type A (OR 1.28), B (OR 1.33) or AB (OR 1.43) vs. O. These results suggested that horizontal toxoplasmosis transmission in the Czech Republic may occur through consumption of raw meat, contact with cat faeces and farming.

• MeSH
• financování organizované MeSH
• hospodářská zvířata MeSH
• kočky MeSH
• králíci MeSH
• lidé MeSH
• ozbrojené síly MeSH
• prevalence MeSH
• prospektivní studie MeSH
• protilátky protozoální krev   MeSH
• průřezové studie MeSH
• průzkumy a dotazníky MeSH
• psi MeSH
• rizikové faktory MeSH
• séroepidemiologické studie MeSH
• Toxoplasma imunologie   MeSH
• toxoplazmóza zvířat parazitologie   přenos   MeSH
• toxoplazmóza epidemiologie   parazitologie   přenos   MeSH
• zvířata MeSH
• Check Tag
• kočky MeSH
• králíci MeSH
• lidé MeSH
• psi MeSH
• zvířata MeSH
• Geografické názvy
• Česká republika MeSH

OBJECTIVES: Toxoplasma gondii, a parasitic protozoan, infects about 30 - 60% of people worldwide. Toxoplasma is known to induce behavioral changes and an increase of dopamine in mice. The presence of anti-Toxoplasma antibodies (latent toxoplasmosis) is also a risk factor for schizophrenia. Latent toxoplasmosis in men (male soldiers) is associated with lower novelty seeking. As the novelty seeking is supposed to negatively correlate with level of dopamine, the observed effect was interpreted as indirect evidence of increased dopamine levels in subjects with toxoplasmosis. However, it is also possible that the observed effect was caused by association of both novelty seeking and Toxoplasma infection with a third factor, e.g. size of place of residence. METHODS: Personality profile of 290 blood donors (205 men and 85 women) were measured by Cloninger's TCI (Temperament and Character Inventory) and their blood samples were assayed for the presence of anti-Toxoplasma antibodies. Difference between Toxoplasma-infected and Toxoplasma-free subjects was tested with ANCOVA method with gender, size of place of residence, and age as covariates. RESULTS: The present analysis revealed that lower novelty seeking was associated with latent toxoplasmosis both in men and women. The effect of infection on novelty seeking remained significant even after adjustment for size of place of residence (p<0.01). CONCLUSION: Decreased novelty seeking in Toxoplasma-infected subjects have been already confirmed in three independent populations (male soldiers and male and female blood donors). These findings suggest that the local inflammation-induced increase in dopamine in the brain of infected subjects can represent a missing link between toxoplasmosis and schizophrenia.

• MeSH
• dárci krve psychologie   MeSH
• dospělí MeSH
• ELISA MeSH
• financování organizované MeSH
• lidé MeSH
• odměna MeSH
• osobnostní testy MeSH
• pátrací chování fyziologie   MeSH
• protilátky protozoální analýza   MeSH
• toxoplazmóza imunologie   psychologie   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH

Cercariae of bird schistosomes (genus Trichobilharzia) are able to penetrate the skin of mammals (noncompatible hosts), including humans, and cause a Th2-associated inflammatory cutaneous reaction termed cercarial dermatitis. The present study measured the antibody reactivity and antigen specificity of sera obtained after experimental infection of mice and natural infection of humans. Sera from mice re-infected with T. regenti showed a bias towards the development of antigen-specific IgM and IgG1 antibodies and elevated levels of total serum IgE, indicative of a Th2 polarized immune response. We also demonstrate that cercariae are a source of antigens triggering IL-4 release from basophils collected from healthy human volunteers. Analysis of sera from patients with a history of cercarial dermatitis revealed elevated levels of cercarial-specific IgG, particularly for samples collected from adults (> 14 years old) compared with children (8-14 years old), although elevated levels of antigen-specific IgE were not detected. In terms of antigen recognition, IgG and IgE antibodies in the sera of both mice and humans preferentially bound an antigen of 34 kDa. The 34 kDa molecule was present in both homogenate of cercariae, as well as cercarial excretory/secretory products, and we speculate it may represent a major immunogen initiating the Th2-immune response associated with cercarial dermatitis.

• MeSH
• antigeny helmintové chemie   imunologie   MeSH
• bazofily imunologie   MeSH
• dermatitida imunologie   parazitologie   MeSH
• dítě MeSH
• dospělí MeSH
• financování organizované MeSH
• imunoglobulin E MeSH
• imunoglobulin G krev   MeSH
• imunoglobulin M krev   MeSH
• interleukin-4 sekrece   MeSH
• lidé MeSH
• mladiství MeSH
• molekulová hmotnost MeSH
• myši MeSH
• protilátky helmintové krev   MeSH
• Schistosomatidae imunologie   MeSH
• věkové faktory MeSH
• zvířata MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• práce podpořená grantem MeSH

The RhD protein which is the RHD gene product and a major component of the Rh blood group system carries the strongest blood group immunogen, the D-antigen. This antigen is absent in a significant minority of the human population (RhD-negatives) due to RHD deletion or alternation. The origin and persistence of this RhD polymorphism is an old evolutionary enigma. Before the advent of modern medicine, the carriers of the rarer allele (e.g. RhD-negative women in the population of RhD-positives or RhD-positive men in the population of RhD-negatives) were at a disadvantage as some of their children (RhD-positive children born to pre-immunized RhD-negative mothers) were at a higher risk of foetal or newborn death or health impairment from haemolytic disease. Therefore, the RhD-polymorphism should be unstable, unless the disadvantage of carriers of the locally less abundant allele is counterbalanced by, for example, higher viability of the heterozygotes. Here we demonstrated for the first time that among Toxoplasma-free subjects the RhD-negative men had faster reaction times than Rh-positive subjects and showed that heterozygous men with both the RhD plus and RhD minus alleles were protected against prolongation of reaction times caused by infection with the common protozoan parasite Toxoplasma gondii. Our results suggest that the balancing selection favouring heterozygotes could explain the origin and stability of the RhD polymorphism. Moreover, an unequal prevalence of toxoplasmosis in different countries could explain pronounced differences in frequencies of RhD-negative phenotype in geographically distinct populations.

• MeSH
• dárci krve MeSH
• dospělí MeSH
• financování organizované MeSH
• heterozygot MeSH
• krevní skupiny - systém Rh-Hr analýza   genetika   krev   MeSH
• lidé MeSH
• molekulární evoluce MeSH
• ozbrojené síly MeSH
• polymorfismus genetický MeSH
• protilátky protozoální krev   MeSH
• psychomotorický výkon MeSH
• reakční čas fyziologie   MeSH
• selekce (genetika) MeSH
• Toxoplasma imunologie   patogenita   MeSH
• toxoplazmóza parazitologie   prevence a kontrola   MeSH
• zvířata MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH