J Flegr

Summary

Affiliation: Charles University
Country: Czech Republic

Publications

  1. pmc Toxoplasmosis-associated difference in intelligence and personality in men depends on their Rhesus blood group but not ABO blood group
    Jaroslav Flegr
    Department of Biology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
    PLoS ONE 8:e61272. 2013
  2. doi request reprint How and why Toxoplasma makes us crazy
    Jaroslav Flegr
    Faculty of Science, Charles University in Prague, Prague 128 44, Czech Republic
    Trends Parasitol 29:156-63. 2013
  3. pmc Microevolutionary, macroevolutionary, ecological and taxonomical implications of punctuational theories of adaptive evolution
    Jaroslav Flegr
    Jaroslav Flegr, Department of Philosophy and History of Science, Faculty of Science, Charles University in Prague, Vinicna 7, CZ 12844, Praha 2, Czech Republic
    Biol Direct 8:1. 2013
  4. doi request reprint Influence of latent Toxoplasma infection on human personality, physiology and morphology: pros and cons of the Toxoplasma-human model in studying the manipulation hypothesis
    Jaroslav Flegr
    Faculty of Science, Charles University, Department of Philosophy and History of Science, Prague, Czech Republic
    J Exp Biol 216:127-33. 2013
  5. pmc Rhesus factor modulation of effects of smoking and age on psychomotor performance, intelligence, personality profile, and health in Czech soldiers
    Jaroslav Flegr
    Faculty of Science, Charles University in Prague, Prague, Czech Republic
    PLoS ONE 7:e49478. 2012
  6. ncbi request reprint The relation of cortisol and sex hormone levels to results of psychological, performance, IQ and memory tests in military men and women
    Jaroslav Flegr
    Faculty of Science, Charles University in Prague, Biology Dept, Prague, Czech Republic
    Neuro Endocrinol Lett 33:224-35. 2012
  7. pmc Fatal attraction phenomenon in humans: cat odour attractiveness increased for toxoplasma-infected men while decreased for infected women
    Jaroslav Flegr
    Department of Biology, Charles University, Prague, Czech Republic
    PLoS Negl Trop Dis 5:e1389. 2011
  8. pmc Probable neuroimmunological link between Toxoplasma and cytomegalovirus infections and personality changes in the human host
    Martina Novotna
    Department of Parasitology, Charles University, Vinicna 7, Prague 128 44, Czech Republic
    BMC Infect Dis 5:54. 2005
  9. pmc Longer pregnancy and slower fetal development in women with latent "asymptomatic" toxoplasmosis
    Sárka Kaňková
    Department of Parasitology, Charles University in Prague, Faculty of Science, Vinicna 7, CZ 128 44 Praha 2, Czech Republic
    BMC Infect Dis 7:114. 2007
  10. pmc Increased risk of traffic accidents in subjects with latent toxoplasmosis: a retrospective case-control study
    Jaroslav Flegr
    Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
    BMC Infect Dis 2:11. 2002

Collaborators

Detail Information

Publications49

  1. pmc Toxoplasmosis-associated difference in intelligence and personality in men depends on their Rhesus blood group but not ABO blood group
    Jaroslav Flegr
    Department of Biology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
    PLoS ONE 8:e61272. 2013
    ..Subjects with a Rhesus-positive blood group are protected against certain behavioural effects associated with Toxoplasma infection, including the deterioration of reaction times and personality factor shift...
  2. doi request reprint How and why Toxoplasma makes us crazy
    Jaroslav Flegr
    Faculty of Science, Charles University in Prague, Prague 128 44, Czech Republic
    Trends Parasitol 29:156-63. 2013
    ....
  3. pmc Microevolutionary, macroevolutionary, ecological and taxonomical implications of punctuational theories of adaptive evolution
    Jaroslav Flegr
    Jaroslav Flegr, Department of Philosophy and History of Science, Faculty of Science, Charles University in Prague, Vinicna 7, CZ 12844, Praha 2, Czech Republic
    Biol Direct 8:1. 2013
    ..The punctuational theories offer many new predictions that need to be tested, but also provide explanations for a much broader spectrum of known biological phenomena than classical gradualistic evolutionary theories...
  4. doi request reprint Influence of latent Toxoplasma infection on human personality, physiology and morphology: pros and cons of the Toxoplasma-human model in studying the manipulation hypothesis
    Jaroslav Flegr
    Faculty of Science, Charles University, Department of Philosophy and History of Science, Prague, Czech Republic
    J Exp Biol 216:127-33. 2013
    ....
  5. pmc Rhesus factor modulation of effects of smoking and age on psychomotor performance, intelligence, personality profile, and health in Czech soldiers
    Jaroslav Flegr
    Faculty of Science, Charles University in Prague, Prague, Czech Republic
    PLoS ONE 7:e49478. 2012
    ..It is not known, however, whether the RhD phenotype modifies exclusively the response of the body to toxoplasmosis or whether it also influences effects of other factors...
  6. ncbi request reprint The relation of cortisol and sex hormone levels to results of psychological, performance, IQ and memory tests in military men and women
    Jaroslav Flegr
    Faculty of Science, Charles University in Prague, Biology Dept, Prague, Czech Republic
    Neuro Endocrinol Lett 33:224-35. 2012
    ..Cortisol, along with other hormones of hypothalamo-pituitary-adrenal axis, belongs to one of the main factors influencing psychological and pathognomic factors, intelligence, and memory...
  7. pmc Fatal attraction phenomenon in humans: cat odour attractiveness increased for toxoplasma-infected men while decreased for infected women
    Jaroslav Flegr
    Department of Biology, Charles University, Prague, Czech Republic
    PLoS Negl Trop Dis 5:e1389. 2011
    ..While most behavioural effects of toxoplasmosis were confirmed also in humans, neither the fatal attraction phenomenon nor any toxoplasmosis-associated changes in olfactory functions have been searched for in them...
  8. pmc Probable neuroimmunological link between Toxoplasma and cytomegalovirus infections and personality changes in the human host
    Martina Novotna
    Department of Parasitology, Charles University, Vinicna 7, Prague 128 44, Czech Republic
    BMC Infect Dis 5:54. 2005
    ....
  9. pmc Longer pregnancy and slower fetal development in women with latent "asymptomatic" toxoplasmosis
    Sárka Kaňková
    Department of Parasitology, Charles University in Prague, Faculty of Science, Vinicna 7, CZ 128 44 Praha 2, Czech Republic
    BMC Infect Dis 7:114. 2007
    ..The purpose of this study was to confirm that women with latent toxoplasmosis have developmentally younger fetuses at estimated pregnancy week 16 and to test four exclusive hypotheses that could explain the observed data...
  10. pmc Increased risk of traffic accidents in subjects with latent toxoplasmosis: a retrospective case-control study
    Jaroslav Flegr
    Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
    BMC Infect Dis 2:11. 2002
    ..It is not know, however, whether the changes observed in laboratory influence the performance of subjects in real-life situations...
  11. pmc Effects of toxoplasma on human behavior
    Jaroslav Flegr
    Departmeent of Parasitology, Faculty of Science, Charles University, Vinicna 7, CZ 128 44 Praha 2, Czech Republic
    Schizophr Bull 33:757-60. 2007
    ..Other studies have demonstrated reduced psychomotor performance in affected individuals. Possible mechanisms by which T. gondii may affect human behavior include its effect on dopamine and on testosterone...
  12. doi request reprint Sex-dependent toxoplasmosis-associated differences in testosterone concentration in humans
    J Flegr
    Department of Parasitology, Faculty of Sciences, Charles University, Vinicna 7, 128 44 Prague 2, Czech Republic
    Parasitology 135:427-31. 2008
    ..The opposite direction of the testosterone shift in men compared to women can explain the observed gender specificity of behavioural shifts in Toxoplasma-infected subjects...
  13. doi request reprint Brief Communication: Latent toxoplasmosis and salivary testosterone concentration--important confounding factors in second to fourth digit ratio studies
    Jaroslav Flegr
    Department of Philosophy and History of Sciences, Faculty of Sciences, Charles University, 128 44 Prague 2, Czech Republic
    Am J Phys Anthropol 137:479-84. 2008
    ....
  14. ncbi request reprint Neurophysiological effect of the Rh factor. Protective role of the RhD molecule against Toxoplasma-induced impairment of reaction times in women
    Jaroslav Flegr
    Department of Philosophy and History of Natural Science, Charles University, Vinicna 7, Prague 128 44, Czech Republic
    Neuro Endocrinol Lett 29:475-81. 2008
    ..No phenotypic effect of RhD protein, except its role in hemolytic disease of newborns and protective role against Toxoplasma-induced impairment of reaction times in men, has been described...
  15. pmc Increased incidence of traffic accidents in Toxoplasma-infected military drivers and protective effect RhD molecule revealed by a large-scale prospective cohort study
    Jaroslav Flegr
    Department of Philosophy, Faculty of Science, Charles University, Prague, Czech Republic
    BMC Infect Dis 9:72. 2009
    ..In the present study we searched for increased incidence of traffic accidents and for protective effect of RhD positivity in 3890 military drivers...
  16. ncbi request reprint Influence of latent 'asymptomatic' toxoplasmosis on body weight of pregnant women
    Jaroslav Flegr
    Department of Parasitology, Charles University, Prague, Czech Republic
    Folia Parasitol (Praha) 52:199-204. 2005
    ..The prevalence of latent toxoplasmosis is extremely high. Therefore, even its mild symptoms such as the decreased body weight in Toxoplasma-positive pregnant women might in fact indicate an unrecognized serious public health problem...
  17. doi request reprint A possible role of intracellular isoelectric focusing in the evolution of eukaryotic cells and multicellular organisms
    Jaroslav Flegr
    Department of Philosophy and History of Science, Charles University, Vinicna 7, 128 44, Praha 2, Czech Republic
    J Mol Evol 69:444-51. 2009
    ....
  18. ncbi request reprint Was Lysenko (partly) right? Michurinist biology in the view of modern plant physiology and genetics
    Jaroslav Flegr
    Department of Parasitology and Hydrobiology, Faculty of Science, Charles University, Vinicna 7, Prague 2, CZ 128 44 Czech Republic
    Riv Biol 95:258-72. 2002
    ..e., by a theory of frozen plasticity...
  19. ncbi request reprint Decreased level of psychobiological factor novelty seeking and lower intelligence in men latently infected with the protozoan parasite Toxoplasma gondii Dopamine, a missing link between schizophrenia and toxoplasmosis?
    Jaroslav Flegr
    Department of Parasitology, Charles University, Vinicna 7, 128 44, Prague, Czech Republic
    Biol Psychol 63:253-68. 2003
    ..003) and lower probability of achieving a higher education (P(2)<0.0000). Decrease of NS suggests that the increase of dopamine in brain of infected subjects can represent a missing link between toxoplasmosis and schizophrenia...
  20. ncbi request reprint Body height, body mass index, waist-hip ratio, fluctuating asymmetry and second to fourth digit ratio in subjects with latent toxoplasmosis
    J Flegr
    Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
    Parasitology 130:621-8. 2005
    ....
  21. ncbi request reprint Testosterone and cortisol levels in university students reflect actual rather than estimated number of wrong answers on written exam
    Jaroslav Flegr
    Faculty of Science, Charles University in Prague, Vinicna 7, Praha, Czech Republic
    Neuro Endocrinol Lett 31:577-81. 2010
    ..It is possible that the complicated patterns in humans result from the methods limitations--measurement of hormone concentrations in simulated competitive events or sport instead in real-life situations...
  22. pmc Potential immunomodulatory effects of latent toxoplasmosis in humans
    Jaroslav Flegr
    Biology Departments, Charles University in Prague, Czech Republic
    BMC Infect Dis 11:274. 2011
    ..For example, the immunosuppression hypothesis explains the higher probability of the birth of male offspring observed in Toxoplasma-positive humans and mice by the protection of the (more immunogenic) male embryos against abortion...
  23. pmc Elastic, not plastic species: frozen plasticity theory and the origin of adaptive evolution in sexually reproducing organisms
    Jaroslav Flegr
    Department of Philosophy and History of Science, Charles University, Vinicna 7, CZ 128 44 Praha 2, Czech Republic
    Biol Direct 5:2. 2010
    ..Two models, the selfish gene theory and frozen plasticity theory were suggested to explain evolution of adaptive traits in sexual organisms in past 30 years...
  24. doi request reprint Toxoplasma and reaction time: role of toxoplasmosis in the origin, preservation and geographical distribution of Rh blood group polymorphism
    M Novotna
    Department of Parasitology, Charles University, Prague 128 44, Czech Republic
    Parasitology 135:1253-61. 2008
    ..Moreover, an unequal prevalence of toxoplasmosis in different countries could explain pronounced differences in frequencies of RhD-negative phenotype in geographically distinct populations...
  25. ncbi request reprint New and old risk-factors for Toxoplasma gondii infection: prospective cross-sectional study among military personnel in the Czech Republic
    P Kolbekova
    Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
    Clin Microbiol Infect 13:1012-7. 2007
    ..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...
  26. ncbi request reprint Influence of latent toxoplasmosis on the secondary sex ratio in mice
    S Kaňková
    Department of Parasitology, Faculty of Science, Charles University in Prague, Vinicna 7, CZ 128 44 Prague 2, Czech Republic
    Parasitology 134:1709-17. 2007
    ....
  27. ncbi request reprint Influence of chronic toxoplasmosis on some human personality factors
    J Flegr
    Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
    Folia Parasitol (Praha) 41:122-6. 1994
    ....
  28. ncbi request reprint Decrease of psychomotor performance in subjects with latent 'asymptomatic' toxoplasmosis
    J Havlicek
    Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
    Parasitology 122:515-20. 2001
    ....
  29. ncbi request reprint Changes in the personality profile of young women with latent toxoplasmosis
    J Flegr
    Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
    Folia Parasitol (Praha) 46:22-8. 1999
    ..The difference in several other factors (desurgency/surgency, alaxia/protension, naiveté/shrewdness, and self-sentiment integration) concerned changes in the variances, rather than the mean values of the factors...
  30. doi request reprint Increased pregnancy weight gain in women with latent toxoplasmosis and RhD-positivity protection against this effect
    S Kaňková
    Department of Parasitology, Faculty of Science, Charles University in Prague, Vinicna 7, CZ 12844 Prague 2, Czech Republic
    Parasitology 137:1773-9. 2010
    ..RhD-positive subjects are protected against toxoplasmosis-associated impairment of psychomotor performance. Here we searched for RhD-positivity-associated maternal protection against the effects of toxoplasmosis...
  31. ncbi request reprint Correlation of duration of latent Toxoplasma gondii infection with personality changes in women
    J Flegr
    Department of Parasitology, Charles University, Prague, Czech
    Biol Psychol 53:57-68. 2000
    ..The same evidence questions the view that women with a particular personality profile are more prone to acquisition of T. gondii infection...
  32. ncbi request reprint Women infected with parasite Toxoplasma have more sons
    S Kaňková
    Department of Parasitology, Charles University, Vinicna 7, 128 44, Prague 2, Czech Republic
    Naturwissenschaften 94:122-7. 2007
    ..In light of the high prevalence of latent toxoplasmosis in most countries, the impact of toxoplasmosis on the human population might be considerable...
  33. ncbi request reprint The role of dopamine in Toxoplasma-induced behavioural alterations in mice: an ethological and ethopharmacological study
    A Skallová
    Department of Parasitology, Faculty of Science, Charles University, Vinicna 7, Prague 128 44, Czech Republic
    Parasitology 133:525-35. 2006
    ..These results suggest an association between Toxoplasma gondii infection and changes in the dopaminergic neuromodulatory system...
  34. ncbi request reprint Poorer results of mice with latent toxoplasmosis in learning tests: impaired learning processes or the novelty discrimination mechanism?
    H Hodkova
    Department of Parasitology, Charles University, Vinicna 7, Prague 128 44, Czech Republic
    Parasitology 134:1329-37. 2007
    ....
  35. pmc Concordance between genetic relatedness and phenotypic similarities of Trichomonas vaginalis strains
    V Hampl
    Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
    BMC Evol Biol 1:11. 2001
    ..Furthermore, the distribution of endobionts such as mycoplasmas or Trichomonas vaginalis virus (TVV) in the T. vaginalis metapopulation is poorly characterised...
  36. ncbi request reprint Correlation between aerobic and anaerobic resistance to metronidazole in trichomonads: application of a new computer program for permutation tests
    J Flegr
    Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
    Parasitol Res 84:590-2. 1998
    ..natur.cuni.cz/flegr/PROGRAMS/+ ++TREEPT.ZIP and http://www.karlin. mff.cuni.cz/-zaboj/treept...
  37. ncbi request reprint Decreased level of novelty seeking in blood donors infected with Toxoplasma
    Anna Skallová
    Department of Parasitology, Charles University, Vinicna 7, Prague 128 44, Czech Republic
    Neuro Endocrinol Lett 26:480-6. 2005
    ..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...
  38. ncbi request reprint Construction and bootstrap analysis of DNA fingerprinting-based phylogenetic trees with the freeware program FreeTree: application to trichomonad parasites
    V Hampl
    Department of Parasitology, Faculty of Sciences, Charles University, Prague 2, Czech Republic
    Int J Syst Evol Microbiol 51:731-5. 2001
    ..The FreeTree program makes such analysis possible...
  39. ncbi request reprint Higher perceived dominance in Toxoplasma infected men--a new evidence for role of increased level of testosterone in toxoplasmosis-associated changes in human behavior
    Hana Hodková
    Department of Parasitology, Charles University, Vinièná 7, Prague 128 44, Czech Republic
    Neuro Endocrinol Lett 28:110-4. 2007
    ..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...
  40. ncbi request reprint Pattern of money allocation in experimental games supports the stress hypothesis of gender differences in Toxoplasma gondii-induced behavioural changes
    Jitka Lindová
    Department of Philosophy and History of Science, Faculty of Science, Charles University, Vinicna 7, 128 44 Prague, Czech Republic
    Folia Parasitol (Praha) 57:136-42. 2010
    ..016), but both genders appeared less generous when infected in the Dictator Game modified to minimize social connotation (p = 0.048)...
  41. pmc Differences in the 2nd to 4th digit length ratio in humans reflect shifts along the common allometric line
    Lukáš Kratochvíl
    Department of Ecology, Faculty of Science, Charles University in Prague, Vinicna 7, 128 44 Praha 2, Czech Republic
    Biol Lett 5:643-6. 2009
    ..We conclude that previously published results on the 2D : 4D ratio are biased by its covariation with finger length. We strongly recommend regression-based approaches for comparisons of hand shape among different groups...
  42. doi request reprint Differences in onset of disease and severity of psychopathology between toxoplasmosis-related and toxoplasmosis-unrelated schizophrenia
    D Holub
    Medical Faculty Charles University, Hradec Kralove, Czech Republic
    Acta Psychiatr Scand 127:227-38. 2013
    ..Toxoplasmosis is a lifelong parasitic disease that appears to be associated to schizophrenia. However, no distinguishing attributes in Toxoplasma-infected schizophrenia patients have been described as yet...
  43. ncbi request reprint The influence of RhD phenotype on toxoplasmosis- and age-associated changes in personality profile of blood donors
    Jaroslav Flegr
    Biology Section, Faculty of Science, Charles University, Vinicna 7, 128 44 Prague, Czech Republic
    Folia Parasitol (Praha) 57:143-50. 2010
    ..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...
  44. ncbi request reprint Dominance, submissivity (and homosexuality) in general population: testing of evolutionary hypothesis of sadomasochism by Internet-trap-method
    Eva Jozifkova
    Department of Anthropology and Human Genetics, Faculty of Science, Charles University in Prague, Czech Republic
    Neuro Endocrinol Lett 27:711-8. 2006
    ..Here, we studied prevalence and strength of particular preferences in general population by Internet-trap-method...
  45. ncbi request reprint Comparison of european Trichobilharzia species based on ITS1 and ITS2 sequences
    J Dvorak
    Department of Parasitology, Charles University, Prague, Czech Republic
    Parasitology 124:307-13. 2002
    ..franki is more related to the nasal T. regenti, than to the visceral T. szidati. The newly designed primer, which is specific for T. regenti, might be used as a tool for diagnosis of this potential pathogen...
  46. ncbi request reprint Tetratrichomonads from the oral cavity and respiratory tract of humans
    K Kutisova
    Department of Parasitology, Faculty of Science, Charles University in Prague, Vinicna 7, Prague 2, 128 44, Czech Republic
    Parasitology 131:309-19. 2005
    ..Consistent differences between 'bronchial' and 'oral' groups were confirmed by analysis of ITS1-5.8S rRNA-ITS2 sequences. Our results have revealed novel trichomonad species of the human oral cavity and bronchi...
  47. pmc Women's preference for dominant male odour: effects of menstrual cycle and relationship status
    Jan Havlicek
    Department of Anthropology, Faculty of Humanities, Charles University, Husnikova 2075, 155 00 Prague, Czech Republic
    Biol Lett 1:256-9. 2005
    ..In accordance with the theory of mixed mating strategies, this preference varies with relationship status, being much stronger in fertile women in stable relationships than in fertile single women...
  48. ncbi request reprint Inference of the phylogenetic position of oxymonads based on nine genes: support for metamonada and excavata
    Vladimir Hampl
    Department of Parasitology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
    Mol Biol Evol 22:2508-18. 2005
    ....
  49. ncbi request reprint Gender differences in behavioural changes induced by latent toxoplasmosis
    Jitka Lindová
    Department of Parasitology, Faculty of Science, Charles University, Vinicna 7, 128 44, Praha 2, Czech Republic
    Int J Parasitol 36:1485-92. 2006
    ..In the composite behavioural variable Mistrust (analogue to factor L), the pattern was affected by environment (rural versus urban). Possible interpretations of the gender differences are discussed...