Vladislav Raclavsky

Summary

Affiliation: Palacky University
Location: Olomouc, Czech Republic
Summary:
M.D. in 1990, Ph.D. in 1997, works part-time as principal investigator and part-time as routine mycologist in University Hospital.

My aim is to work for rapid translation of new scientific knowledge into clinical microbiology practice for the benefit of patient. I also strive to supplement this translational research by basic research focused on medically relevant topics in yeasts. Individual topics pursued are as follows:

Hypoxia-response in Cryptococcus neoformans
Ability to adapt to oxygen limitation was identified as a signal for unbudded G2-arrest in this obligate aerobic pathogenic yeast. Furthermore, a role of hypoxia response in cryptococcal virulence has emerged recently. Therefore, we focus on characterisation of cryptococcal hypoxia response useful for development of a cultivating system that should serve as a model for cryptococcal growth in human tissue.

Identification and typing of medically relevant yeasts
Recently, the technology of high resolution melting analysis of double-stranded DNA (typically PCR amplicons) is gradually more affordable to routine clinical microbiology laboratories. Therefore, we focus on developing competitive amplification systems which should best cover the whole spectrum of medically important yeast, enabling for their rapid species identification and possibly also strain typing in a convenient automated or semi-automated way. The McRAPD and PCR-HRMA approaches are at the center of our efforts, including development of multi-purpose software QAS useful for quantitative comparison of complex melting data (melting curves).

Publications

  1. Plachy R, Hamal P, Raclavsky V. McRAPD as a new approach to rapid and accurate identification of pathogenic yeasts. J Microbiol Methods. 2005;60:107-13 pubmed
    ..We have termed this new approach melting curve of random amplified polymorphic DNA (McRAPD) to emphasize its rapidity and potential for automation, highly desirable features for a routine laboratory test. ..
  2. Hamal P, Ostransky J, Dendis M, Horvath R, Ruzicka F, Buchta V, et al. A case of endocarditis caused by the yeast Pichia fabianii with biofilm production and developed in vitro resistance to azoles in the course of antifungal treatment. Med Mycol. 2008;46:601-5 pubmed publisher
    ..To our knowledge, this is the first published case of endocarditis and the fourth human infection caused by this yeast species. ..
  3. Raclavsky V, Husičková V, Moranova Z, Ohkusu M, Fischer O, Precek J, et al. Growth strategy of the pathogenic yeast Cryptococcus neoformans submerged culture under different cultivation formats. Folia Microbiol (Praha). 2009;54:349-52 pubmed publisher
  4. Trtkova J, Pavlicek P, Ruskova L, Hamal P, Koukalova D, Raclavsky V. Performance of optimized McRAPD in identification of 9 yeast species frequently isolated from patient samples: potential for automation. BMC Microbiol. 2009;9:234 pubmed publisher
    ..It can also serve as a broad-range high-throughput technique for epidemiological surveillance. ..
  5. Hamal P, Hanzen J, Horn F, Trtkova J, Ruskova L, Vecerova R, et al. Usefulness of McRAPD for typing and importance of biofilm production in a case of nosocomial ventriculoperitoneal shunt infection caused by Candida lusitaniae. Folia Microbiol (Praha). 2011;56:407-14 pubmed publisher
    ..A ventriculoperitoneal shunt colonized by C. lusitaniae was revealed as the source of this nosocomial infection, and the ability of the strain to form biofilm on its surface likely caused treatment failure. ..
  6. Ohkusu M, Raclavsky V, Takeo K. Deficit in oxygen causes G(2) budding and unbudded G(2) arrest in Cryptococcus neoformans. FEMS Microbiol Lett. 2001;204:29-32 pubmed
    ..Thus, a deficit in oxygen was demonstrated to delay the timing of budding, prolong the G(2) phase and cause accumulation of cells after DNA synthesis, but before commitment to budding. ..
  7. Moranova Z, Kawamoto S, Raclavsky V. Hypoxia sensing in cryptococcus neoformans: biofilm-like adaptation for dormancy?. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2009;153:189-93 pubmed
    ..Our further conclusion is that the ability of the immune system and antifungal agents to cope with hypoxia-adapted cells is crucial for the successful eradication of cryptococcal infection. ..
  8. Ruskova L, Raclavsky V. The potential of high resolution melting analysis (hrma) to streamline, facilitate and enrich routine diagnostics in medical microbiology. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2011;155:239-52 pubmed publisher
  9. Raclavsky V, Ohkusu M, Hruskova P, Takeo K. Preparation and characterization of Cryptococcus neoformans synchronous culture. J Microbiol Methods. 2002;51:29-33 pubmed
    ..The C. neoformans synchronous culture system has revealed important characteristics with respect to cellular morphology, DNA content and cell volume distribution. The method can be used for further cell cycle studies. ..

Detail Information

Publications12

  1. Trtkova J, Raclavsky V. Molecular-genetic approaches to identification and typing of pathogenic Candida yeasts. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2006;150:51-61 pubmed
  2. Raclavsky V, Pavlicek J, Novotny R, Moranova Z, Ohkusu M, Trtkova J, et al. Peculiar clusters of daughter cells observed in Cryptococcus neoformans grown in sealed microtiter plates. Folia Microbiol (Praha). 2009;54:369-71 pubmed publisher
    ..However, their daughters were unable to separate from them and to continue their proliferation under such conditions. ..
  3. Raclavsky V, Novotny R, Stary L, Navrátilová L, Zatloukal J, Jakubec P, et al. NAS agar is more suitable than McKay agar for primary culture of Streptococcus milleri group (SMG) fastidious bacteria, S. intermedius in particular. Folia Microbiol (Praha). 2017;62:11-15 pubmed publisher
    ..Therefore, when economic conditions are not limiting and maximum recovery rate is desirable, both plates are advised to be used in parallel for primary cultivation of clinical samples. ..