93 results on '"Dobay O"'
Search Results
2. Varying fitness cost associated with resistance to fluoroquinolones governs clonal dynamic of methicillin-resistant Staphylococcus aureus
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Horváth, A., Dobay, O., Kardos, S., Ghidán, Á., Tóth, Á., Pászti, J., Ungvári, E., Horváth, P., Nagy, K., Zissman, S., and Füzi, M.
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- 2012
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3. Phenotypic and genetic characterisation of methicillin-resistant Staphylococcus aureus strains isolated from the university hospitals of Debrecen
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Szabó, J., Dombrádi, Z., Dobay, O., Orosi, P., Kónya, J., Nagy, K., and Rozgonyi, F.
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- 2009
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4. Serological evidence of adenovirus infection in cats
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Lakatos, B., Farkas, J., Adám, É., Dobay, O., Jeney, Cs., Nász, I., and Ongrádi, J.
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- 2000
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5. Characterization of intertype specific epitopes on adenovirus hexons
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Ádám, É., Nász, I., Hudecz, F., Lengyel, A., Mezö, G., and Dobay, O.
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- 1998
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6. The relationship between serotypes and PFGE genotypes in isolates of Streptococcus pneumoniae from Hungary
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Dobay, O., Rozgonyi, F., Hajdú, E., Nagy, E., Knausz, M., and Amyes, S.G.B.
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- 2005
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7. Comparison of the clonality of penicillin and macrolide non-susceptible pneumococci
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Dobay, O., Rozgonyi, F., and Amyes, S.
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- 2004
8. Comparison of serotyping and genotyping of Hungarian Streptococcus pneumoniae isolates
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Dobay, O., Hajdú, E., Nagy, E., Knausz, M., Rozgonyi, F., and Amyes, S. G. B.
- Published
- 2003
9. Epidemiological analysis of pneumococcal serotype 19A in healthy children following PCV7 vaccination
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TÓTHPÁL, A., primary, LAUB, K., additional, KARDOS, S., additional, TIRCZKA, T., additional, KOCSIS, A., additional, VAN DER LINDEN, M., additional, and DOBAY, O., additional
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- 2015
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10. Genotypic and phenotypic characterisation of invasive Streptococcus pneumoniae isolates from Hungary, and coverage of the conjugate vaccines
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Dobay, O., primary, Ungvari, A., additional, Kardos, S., additional, Kristof, K., additional, Hajdu, E., additional, Szabo, J., additional, Knausz, M., additional, Nagy, E., additional, Rozgonyi, F., additional, Amyes, S. G. B., additional, and Nagy, K., additional
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- 2010
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11. Phenotypic and genetic characterisation of methicillin-resistant Staphylococcus aureus strains isolated from the university hospitals of Debrecen
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Szabó, J., primary, Dombrádi, Z., additional, Dobay, O., additional, Orosi, P., additional, Kónya, J., additional, Nagy, K., additional, and Rozgonyi, F., additional
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- 2008
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12. P691 Vancomycin-resistant enterococci still persist in slaughtered poultry in Hungary 8 years after the ban on avoparcin
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Ghidan, A., primary, Dobay, O., additional, Kaszanyitzky, E., additional, Samu, P., additional, Amyes, S., additional, Nagy, K., additional, and Rozgonyi, F., additional
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- 2007
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13. P1852 Direct comparison of pulsed-.eld gel electrophoresis and multilocus sequence typing
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Dobay, O., primary, Rozgonyi, F., additional, Walsh, F., additional, Diggle, M., additional, Nagy, K., additional, and Amyes, S., additional
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- 2007
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14. P1429 Serotyping of Streptococcus pneumoniae by PCR-expansion of the method to identify the Hungarian serotypes
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Dobay, O., primary, Nagy, K., additional, Amyes, S., additional, and Rozgonyi, F., additional
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- 2007
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15. The First Steps Towards Fluoroquinolone Resistance in Hungarian Pneumococci
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Dobay, O., primary, Rozgonyi, F., additional, Ghidán, Á, additional, Matuz, M., additional, Nagy, K., additional, and Amyes, S.G.B., additional
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- 2006
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16. Molecular characterisation of bovine faecal Escherichia coli shows persistence of defined ampicillin resistant strains and the presence of class 1 integrons on an organic beef farm
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HOYLE, D, primary, DAVISON, H, additional, KNIGHT, H, additional, YATES, C, additional, DOBAY, O, additional, GUNN, G, additional, AMYES, S, additional, and WOOLHOUSE, M, additional
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- 2006
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17. Antibiotic susceptibility and serotypes of Streptococcus pneumoniae isolates from Hungary
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Dobay, O., primary
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- 2003
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18. Adenovirus Infection in Cats. An Epidemiological Survey in the Czech Republic
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Lakatos, B., primary, Knotek, Z., additional, Farkas, J., additional, Ádám, É., additional, Dobay, O., additional, and Nász, I., additional
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- 1999
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19. Taguchi optimisation of ELISA procedures
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Jeney, C., Dobay, O., Lengyel, A., Adam, E., and Nasz, I.
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- 1999
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20. Fast method to remove UV absorbing agarose gel contamination from DNA samples
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Csaba Jeney, Dobay O, Adám E, and Nász I
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Electrophoresis, Agar Gel ,Spectrophotometry ,Chromatography, Gel ,DNA - Abstract
Agarose gel electrophoresis and subsequent purification of DNA bands from the agarose gel is a widely used molecular biological method. There are different methods to achieve this goal, however they have different advantages and disadvantages. One major problem is the presence of different contaminants in the final sample. We developed a method which is effective in removal of the agarose contaminants.
21. Are volatile isolates containing glucosinolate breakdown products overlooked in testing the activity against mycotoxigenic Penicillium verrucosum?
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Ramić, Dina, Vrca, Ivana, Bilušić, Tea, Blažević, Ivica, Smole Možina, Sonja, Marialigeti, K., and Dobay, O.
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penicillium verrucosum ,antifungal activity ,nasturtium volatile isolate ,benzyl isothiocyanate ,2-phenylacetonirile - Abstract
Moulds that cause food spoilage are a huge problem in the food industry, especially mycotoxin- producing moulds, which pose a major health risk to food consumers. Penicillium verrucosum is one of the major producers of ochratoxin A (OTA) in food. International Agency for Research on Cancer (IARC) classifies OTA as a nephrotoxic, neurotoxic, hepatoxic, teratogenic, genotoxic, immunotoxic, embryotoxic, and carcinogenic toxin. Traditionally, mould growth and OTA production in foods have been controlled by the use of various chemical additives, but nowadays there is an increasing demand from consumers to avoid chemical food additives, which has prompted researchers to search for new safe and biodegradable preservatives. Many studies indicate that essential oils (EOs) and volatile isolates (VIs) rich in low molecular weight phenolic and terpenoid compounds are promising alternative antifungal agents, but there haven’t been many studies showing the antifungal activity of EOs and VIs rich in glucosinolate breakdown products, such as isothiocyanates, nitriles, epithionitriles, and thiocyanates. For that purpose, the antifungal activity of nasturtium (Tropaeolum majus L.) VI was tested. The nasturtium seeds powder was subjected to microwave hydrodiffusion and gravity (MHG) for 15 min at a power of 500 W using an ETHOS X device, and further hydrodistillated with Clevenger system for 2.5 hours to obtain a VI. The chemical composition of nasturtium VI was determined by GC-MS/MS, while the minimal inhibitory concentrations (MIC) of nasturtium VI and its pure compounds (benzyl isothiocyanate, 2- phenylacetonitrile) against P. verrucosum were determined by microdilution method. GC-MS/MS analysis revealed that nasturtium VI was mainly composed of benzyl isothiocyanate (54.35%), and 2- phenylacetonitrile (37%). Among these compounds, nasturtium VI was the most effective with MIC value of 0.05 mg/mL. Excellent antifungal activity was also found for pure benzyl isothiocyanate with MIC value of 0.10 mg/mL, while pure 2- phenylacetonitrile was 8 fold lower with MIC value of 0.8 mg/mL. For comparison, Jeršek et al. (2014) found that oregano EO, mainly composed of phenolic compounds thymol (4.5%) and carvacrol (53.4%), had a MIC of 1.09 mg/mL. The most potent of these compounds was thymol with a MIC of 0.12 mg/mL, while carvacrol had a MIC of 0.38 mg/mL. Thus, it can be concluded that nasturtium VI, which is rich in glucosinolate breakdown products (benzyl isothiocyanate, 2-phenylacetonitrile), has ca. 20 times better antifungal activity against P. verrucosum than oregano EO. It can be assumed that isothiocyanates are the main compounds that confer excellent antifungal activity to nasturtium VI. This result indicates that VIs rich in glucosinolate breakdown products, which are not typically used in mould control studies, are a promising alternative to phenol-rich EOs. Isothiocyanates are lipophilic and therefore can react with membrane-bound enzymes, inhibit fungal growth and cause cell death. In addition, benzyl isothiocyanate is known for its inhibitory effect on mycotoxin production, such as AME, AOH, ALT and TEN (Wang et al., 2020). Therefore, it is necessary to determine the effect of nasturtium VI, benzyl isothiocyanate and 2-phenylacetonitrile on mycotoxin production of P. verrucosum. It is also important to test synergism between the glucosinolate breakdown products in the further studies.
- Published
- 2021
22. Cefotaximase (CTX-M) and quinolone resistance genes (qnr) with additional antimicrobial resistance mechanisms in commensal E. coli from healthy pigs
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Szmolka, Ama, Prukner-Radovcic, Estella, Krizek, Ivan, Nagy, Béla, and Marialigeti, K., Dobay, O.
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Cefotaximase (CTX-M) ,quinolone resistance genes (qnr) ,antimicrobial resistance ,E. coli ,pigs - Abstract
Concerning the importance of food producing animals as potential reservoirs of enteric bacteria with clinically relevant antimicrobial resistance traits, we tested the prevalence of extended-spectrum β-lactamase (ESBL)-producing and fluroquinolone resistant E. coli from pigs in order identify multiple resistance mechanisms circulating in pig farms in Hungary and Croatia with special regards to plasmid mediated genes encoding cefotaximases (CTX-M) and quinolone resistance (qnr). For this purpose, faecal samples were collected from pigs representing three farms from Hungary and six farms from Croatia with 45 and 60 samples respectively. Farms were located in separate regions of the countries. Cefotaxime or nalidixic acid resistance were used as prime markers for the isolation of multiresistant E. coli strains. A second selection was based on resistance to additional antimicrobials (i.e. gentamicin) aiming to reduce the collection to isolates with representative multiresistance phenotypes. In several cases more than two different multiresistance phenotypes have been isolated from the same pig, which were considered as independent E. coli isolates. This collection of multidrug resistant E. coli contained 139 strains and was tested for the presence of blaCTX-M and qnr genes by PCR. Selected isolates carrying genes blaCTX-M and/or qnr are being subjected for confirmation and further typing of antimicrobial resistance genes by using the PCR-microarray AMR05. Cefotaxim resistant E. coli have been detected in one Hungarian and one Croatian farm representing 17% of all pigs tested. In majority of the strains, the plasmid-related resistance phenotypes such as ampicillin, cefotaxim, gentamicin and tetracycline occurred in multiple combinations. In 11% of the strains the coexistence of Ctx-Nal phenotypes was detected, together with the presence of the cefotaximase gene blaCTX-M. E. coli strains with nalidixin resistance phenotype have been predominantly (70%) characterizing healthy pigs independently from the farm and country of isolation. Ciprofloxacin resistant strains occured on one farm only. The plasmid-mediated fluoroquinolone resistance gene qnrS was identified in 11% of the strains, with or without the nalidixin-ciprofloxacin resistant phenotype, while genes qnrA and qnrB were absent. Overall, our results lead to conclude that multiresistant commensal E. coli strains carrying plasmid-mediated CTX-M type cefotaximase and/or quinolone resistance genes in different combinations are widespread on some pig farms but much less on others, most likely reflecting differences in use of antimicrobials.
- Published
- 2015
23. High clonal diversity of Staphylococcus aureus isolates from children's playgrounds in Hungary.
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Horváth A, Tormássi Á, Hajósi-Kalcakosz S, Huber A, Sahin-Tóth J, and Dobay O
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- Hungary epidemiology, Humans, Child, Anti-Bacterial Agents pharmacology, Staphylococcal Infections microbiology, Staphylococcal Infections epidemiology, Microbial Sensitivity Tests, Genetic Variation, Play and Playthings, Staphylococcus aureus genetics, Staphylococcus aureus isolation & purification, Staphylococcus aureus drug effects, Staphylococcus aureus pathogenicity, Staphylococcus aureus classification, Multilocus Sequence Typing, Virulence Factors genetics
- Abstract
Staphylococcus aureus is one of the most important human pathogenic bacteria and environmental surfaces play an important role in the spread of the bacterium. Presence of S. aureus on children's playgrounds and on toys was described in international studies, however, little is known about the prevalence and characteristics of S. aureus at playgrounds in Europe. In this study, 355 samples were collected from playgrounds from 16 cities in Hungary. Antibiotic susceptibility of the isolates was tested for nine antibiotics. Presence of virulence factors was detected by PCR. Clonal diversity of the isolates was tested by PFGE and MLST. The overall prevalence of S. aureus was 2.81% (10/355) and no MRSA isolates were found. Presence of spa (10), fnbA (10), fnbB (5), icaA (8), cna (7), sea (2), hla (10), hlb (2) and hlg (6) virulence genes were detected. The isolates had diverse PFGE pulsotypes. With MLST, we have detected isolates belonging to ST8 (CC8), ST22 (CC22), ST944 and ST182 (CC182), ST398 (CC398), ST6609 (CC45), ST3029 and ST2816. We have identified a new sequence type, ST6609 of CC45. S. aureus isolates are present on Hungarian playgrounds, especially on plastic surfaces. The isolates were clonally diverse and showed resistance to commonly used antibiotics. These data reinforce the importance of the outdoor environment in the spread for S. aureus in the community., (© 2024. The Author(s).)
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- 2024
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24. Prevalence, serogroup distribution and risk factors of Neisseria meningitidis carriage in high school and university students in Hungary.
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Huber A, Kovács E, Horváth A, Sahin-Tóth J, Kaptás Á, Juhász E, Kristóf K, and Dobay O
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- Male, Female, Young Adult, Humans, Adolescent, Adult, Serogroup, Universities, Prevalence, Hungary epidemiology, Risk Factors, Students, Carrier State epidemiology, Carrier State microbiology, Neisseria meningitidis, Meningococcal Infections epidemiology, Meningococcal Infections microbiology, Meningococcal Vaccines
- Abstract
Neisseria meningitidis causes life-threatening invasive meningococcal disease (IMD) with high mortality worldwide. Asymptomatic pharyngeal meningococcus colonisation is an important reservoir for the spread of the bacterium. The aim of this study was to determine N. meningitidis colonisation rates in asymptomatic high school and university students and to identify risk factors for carriage. Oropharyngeal swab samples and data from a self-reported questionnaire were obtained from overall 610 students, among them 303 university students and 307 high school students, aged between 15 and 31 years in Budapest, Hungary, between November 2017 and December 2018. Meningococcal carriage and serogroup of N. meningitidis were determined by RT-PCR from DNA extracted directly from the specimen. N. meningitidis was identified in 212 (34.8 %) of the participants. Significantly higher carriage rate was found among high school students (48.9 %) compared to university students (20.5 %). Peak of colonisation rate was among 17-19-year-old students (48.7 %). Most carriage isolates were non-typable (87.3 %). From the 212 meningococcus carriers, 19 were colonised by serogroup B (9 %), 5 by serogroup C (2.4 %), and 1 had serogroup Y (0.5 %). Significantly higher colonisation rate was found among males (42.4 %) than in females (33.1 %). Antibiotic use in the past 2 months has decreased the rate of meningococcal colonisation. Recent respiratory infection, active or passive smoking and attending parties have not influenced meningococcal colonisation rate significantly. In conclusion, we have found high asymptomatic meningococcus carriage rate among high school students and young adults, however, the majority of the colonizing meningococci were non-typable., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
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- 2024
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25. Genomic Evidence for Direct Transmission of mecC -MRSA between a Horse and Its Veterinarian.
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Albert E, Sahin-Tóth J, Horváth A, Papp M, Biksi I, and Dobay O
- Abstract
Methicillin-resistant Staphylococcus aureus bearing the mecC gene ( mecC -MRSA) has been reported from animals and humans in recent years. This study describes the first mecC -MRSA isolates of human and equine origin in Hungary (two isolates from horses and one from a veterinarian, who treated one of the infected horses, but was asymptomatic). MRSA isolates were identified by cultivation and PCR detection of the species-specific spa gene and mecA / mecC methicillin resistance genes. The isolates were characterized by antibiotic susceptibility testing, MLST, spa , SCCmec typing, PFGE and whole genome sequencing (WGS). All three isolates belonged to the ST130-t843- SCCmec XI genotype, and carried the mecC and blaZ genes. Apart from beta-lactam drugs, they were sensitive to all tested antibiotics. The isolates of the infected horse and its veterinarian had the same PFGE pulsotype and showed only slight differences with WGS. Hence, this is the first description of direct transmission of a mecC -carrying MRSA between a horse and its veterinarian. The emergence of mecC in the country highlights the importance of the appropriate diagnostics in MRSA identification.
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- 2023
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26. Prevalence of Staphylococcus aureus in wild hedgehogs (Erinaceus europaeus) and first report of mecC-MRSA in Hungary.
- Author
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Sahin-Tóth J, Albert E, Juhász A, Ghidán Á, Juhász J, Horváth A, Steward MC, and Dobay O
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- Animals, Anti-Bacterial Agents, Bacterial Proteins genetics, Cattle, Hedgehogs, Humans, Hungary epidemiology, Microbial Sensitivity Tests, Prevalence, Staphylococcus aureus genetics, Methicillin-Resistant Staphylococcus aureus genetics
- Abstract
In 2011 mecC, a new mecA gene homologue, was described in a bovine isolate in the UK. Since then, mecC-positive methicillin-resistant Staphylococcus aureus (mecC-MRSA) has also been found in wild animals. An especially high prevalence of mecC-MRSA has been reported among hedgehogs in Sweden (64%) and Denmark (61%). Based on these findings we aimed to survey the hedgehog population for mecC-MRSA in Hungary. Altogether 200 hedgehogs were screened for Staphylococcus aureus using a culture-based method. The antibiotic susceptibility of the isolates to nine drugs was determined, their genetic relatedness was established by PFGE and spa-typing, and virulence genes were identified by PCR. Whole genome sequencing was performed for the single mecC-MRSA isolate found. Of the 200 animals, 13 were carriers of S. aureus (6.5%). Among these, one isolate was mecA positive and one was mecC positive. The isolates were susceptible to non-beta-lactam antibiotics. Toxin genes were not found, but the majority carried genes responsible for adhesion and biofilm production. The mecC-MRSA isolate was a single-locus variant of ST130, had a new spa type (t19701) and belonged to SCCmec type XI. It carried a recently described, novel exfoliative toxin (etE). This is the first report of mecC-MRSA in Hungary and the first survey of staphylococcus carriage among wild animals in the country. The mecC prevalence was much lower than in Northern European countries and rather similar to other countries in our region. MecC-MRSA could potentially emerge as a novel human pathogen, especially where close contact occurs between humans and animals., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2022
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27. Bicarbonate Evokes Reciprocal Changes in Intracellular Cyclic di-GMP and Cyclic AMP Levels in Pseudomonas aeruginosa .
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Ruksakiet K, Stercz B, Tóth G, Jaikumpun P, Gróf I, Tengölics R, Lohinai ZM, Horváth P, Deli MA, Steward MC, Dobay O, and Zsembery Á
- Abstract
The formation of Pseudomonas aeruginosa biofilms in cystic fibrosis (CF) is one of the most common causes of morbidity and mortality in CF patients. Cyclic di-GMP and cyclic AMP are second messengers regulating the bacterial lifestyle transition in response to environmental signals. We aimed to investigate the effects of extracellular pH and bicarbonate on intracellular c-di-GMP and cAMP levels, and on biofilm formation. P. aeruginosa was inoculated in a brain−heart infusion medium supplemented with 25 and 50 mM NaCl in ambient air (pH adjusted to 7.4 and 7.7 respectively), or with 25 and 50 mM NaHCO3 in 5% CO2 (pH 7.4 and 7.7). After 16 h incubation, c-di-GMP and cAMP were extracted and their concentrations determined. Biofilm formation was investigated using an xCelligence real-time cell analyzer and by crystal violet assay. Our results show that HCO3− exposure decreased c-di-GMP and increased cAMP levels in a dose-dependent manner. Biofilm formation was also reduced after 48 h exposure to HCO3−. The reciprocal changes in second messenger concentrations were not influenced by changes in medium pH or osmolality. These findings indicate that HCO3− per se modulates the levels of c-di-GMP and cAMP, thereby inhibiting biofilm formation and promoting the planktonic lifestyle of the bacteria.
- Published
- 2021
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28. Whole genome sequencing of coagulase positive staphylococci from a dog-and-owner screening survey.
- Author
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Sahin-Tóth J, Kovács E, Tóthpál A, Juhász J, Forró B, Bányai K, Havril K, Horváth A, Ghidán Á, and Dobay O
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- Animals, Bacterial Proteins genetics, Bacterial Proteins isolation & purification, Dog Diseases transmission, Humans, Multilocus Sequence Typing, Staphylococcal Infections transmission, Staphylococcus genetics, Staphylococcus aureus genetics, Staphylococcus aureus isolation & purification, Whole Genome Sequencing, Coagulase genetics, Dog Diseases microbiology, Dogs microbiology, Staphylococcal Infections microbiology, Staphylococcal Infections veterinary, Staphylococcus enzymology
- Abstract
Background: Staphylococcus aureus and S. pseudintermedius are the two most common coagulase positive staphylococci (CPS). S. aureus is more prevalent among humans, whereas S. pseudintermedius is more commonly isolated from dogs, however, both can cause various community and hospital acquired diseases in humans., Methods: In the current study we screened 102 dogs and 84 owners in Hungary. We tested the antibiotic susceptibility of the strains and in order to get a better picture of the clonal relationship of the strains, we used pulsed-field gel electrophoresis. In addition, three pairs of isolates with identical PFGE patterns were whole genome sequenced, MLST and spa types were established., Results: Carriage rate of S. aureus was 23.8% in humans and 4.9% in dogs and two cases of co-carriage were found among dogs and owners. S. pseudintermedius carriage rate was 2.4% and 34.3%, respectively, with only one co-carriage. The isolates were generally rather susceptible to the tested antibiotics, but high tetracycline resistance of S. pseudintermedius strains was noted. The co-carried isolates shared almost the same resistance genes (including tet(K), bla(Z), norA, mepR, lmrS, fosB) and virulence gene pattern. Apart from the common staphylococcal enzymes and cytotoxins, we found enterotoxins and exfoliative toxins as well. The two S. aureus pairs belonged to ST45-t630, ST45-t671 and ST15-t084, ST15-t084, respectively. The co-carried S. pseudintermedius isolates shared the same housekeeping gene alleles determining a novel sequence type ST1685., Conclusions: Based on the genomic data, dog-owner co-carried strains displayed only insignificant differences therefore provided evidence for potential human-to-dog and dog-to-human transmission., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2021
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29. Antibacterial Effects of Bicarbonate in Media Modified to Mimic Cystic Fibrosis Sputum.
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Jaikumpun P, Ruksakiet K, Stercz B, Pállinger É, Steward M, Lohinai Z, Dobay O, and Zsembery Á
- Subjects
- Culture Media chemistry, Humans, Anti-Bacterial Agents chemistry, Bicarbonates chemistry, Cystic Fibrosis, Pseudomonas aeruginosa growth & development, Sputum chemistry, Sputum metabolism, Staphylococcus aureus growth & development
- Abstract
Cystic fibrosis (CF) is a hereditary disease caused by mutations in the gene encoding an epithelial anion channel. In CF, Cl
- and HCO3 - hyposecretion, together with mucin hypersecretion, leads to airway dehydration and production of viscous mucus. This habitat is ideal for colonization by pathogenic bacteria. We have recently demonstrated that HCO3 - inhibits the growth and biofilm formation of Pseudomonas aeruginosa and Staphylococcus aureus when tested in laboratory culture media. Using the same bacteria our aim was to investigate the effects of HCO3 - in artificial sputum medium (ASM), whose composition resembles CF mucus. Control ASM containing no NaHCO3 was incubated in ambient air (pH 7.4 or 8.0). ASM containing NaHCO3 (25 and 100 mM) was incubated in 5% CO2 (pH 7.4 and 8.0, respectively). Viable P. aeruginosa and S. aureus cells were counted by colony-forming unit assay and flow cytometry after 6 h and 17 h of incubation. Biofilm formation was assessed after 48 h. The data show that HCO3 - significantly decreased viable cell counts and biofilm formation in a concentration-dependent manner. These effects were due neither to extracellular alkalinization nor to altered osmolarity. These results show that HCO3 - exerts direct antibacterial and antibiofilm effects on prevalent CF bacteria.- Published
- 2020
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30. Attitudes towards varicella vaccination in parents and paediatric healthcare providers in Hungary.
- Author
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Huber A, Gazder J, Dobay O, Mészner Z, and Horváth A
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- Child, Cross-Sectional Studies, Health Knowledge, Attitudes, Practice, Humans, Hungary, Parents, Surveys and Questionnaires, Vaccination, Chickenpox prevention & control
- Abstract
Background: Varicella vaccination is important in prevention of childhood infection. Aim of this cross-sectional study was to survey attitudes and determinants of support or refusal of varicella vaccination in parents and in paediatric healthcare professionals, mainly health visitors in Hungary prior to the introduction of this vaccine in National Immunization Program in 2019., Methods: Between October 2018 and February 2019, 1042 parents and 198 healthcare professionals completed a self-administered anonymous questionnaire regarding sociodemographic background, knowledge and attitudes towards varicella vaccination, and reasons for non-vaccination., Results: From the participating parents 53.3% have vaccinated at least one of their children. Vaccination rate was significantly higher in families with <3 children, living in the capital, among those who have seen complications of varicella and among parents with university degree. Most important positive determinant was recommendation of the vaccine by healthcare professionals: 77.8% of parents accepted vaccination when recommended by the paediatrician, despite the cost of the vaccine, whereas only 17.3% of parents vaccinated their children when the vaccine was not recommended by paediatrician. Most important reasons for non-vaccination was finding the vaccine unnecessary, concerns regarding side effects, and not believing in the vaccine's effectiveness. Among paediatric healthcare professionals, support rate of universal varicella vaccination was 76.3%. Support rate was higher among those who have seen complications of varicella more often and those who consider varicella a severe infection. Reasons of professionals who do not support universal varicella vaccination were similar to those of vaccine hesitant parents. Practice of intentional exposure of non-immune child to infected ones still exist., Conclusions: Educational programs are needed for parents and health visitors to address concerns regarding vaccination. Paediatricians are the most trusted source of information for parents hence they have a significant responsibility and parents likely follow their recommendations., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2020
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31. Characterisation of antibiotic resistance, virulence, clonality and mortality in MRSA and MSSA bloodstream infections at a tertiary-level hospital in Hungary: a 6-year retrospective study.
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Horváth A, Dobay O, Sahin-Tóth J, Juhász E, Pongrácz J, Iván M, Fazakas E, and Kristóf K
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Bacteremia microbiology, Child, Child, Preschool, Female, Genotype, Humans, Hungary, Infant, Infant, Newborn, Male, Methicillin Resistance, Methicillin-Resistant Staphylococcus aureus classification, Methicillin-Resistant Staphylococcus aureus genetics, Middle Aged, Mortality, Retrospective Studies, Staphylococcal Infections genetics, Tertiary Care Centers, Young Adult, Drug Resistance, Multiple, Bacterial, Staphylococcal Infections microbiology, Staphylococcus aureus classification, Staphylococcus aureus drug effects, Staphylococcus aureus genetics, Virulence Factors genetics
- Abstract
Background: Staphylococcus aureus bloodstream infections (BSI) cause significant morbidity and mortality due to the frequent antibiotic resistance, toxin and adhesin production of the bacterium. These characteristics differ significantly in methicillin resistant (MRSA) and methicillin sensitive S. aureus (MSSA) and also among isolates of different MRSA clones, contributing to the outcome of S. aureus bacteraemia., Methods: In this study, all MRSA BSI isolates from Semmelweis University, Budapest, Hungary, isolated between 2011-2016 and the same number of matched MSSA (overall 306 isolates) were characterised in terms of antibiotic susceptibility, virulence genes, clonality and their association with all-cause 30-day mortality. Effect of patient related variables, such as age, gender and comorbidities were also investigated., Results: ST22-MRSA-IV and ST5-MRSA-II were the most prevalent clones in our study. SCCmec I isolates showed the highest resistance rates and SCCmec II carried most virulence genes. Infections caused by SCCmec IV isolates were associated with the highest mortality rate (42.2%), despite the similar comorbidity rates of the different patient groups. All-cause 30-day mortality was 39.9% in the MRSA and 30.7% in the MSSA group. Increased teicoplanin MIC was associated with high mortality rate. Resistance to ciprofloxacin, erythromycin and clindamycin was common in MRSA, whereas MSSA isolates were more sensitive to all antibiotics with the exception of doxycycline. All MRSA isolates were sensitive to glycopeptides and linezolid; resistance to rifampicin and sulfamethoxazole-trimethoprim was low. MRSA isolates carried more adhesion genes, superantigens were more frequent in MSSA. Panton-Valentine leukocidin was found in 2.3% of the isolates., Conclusion: This study provides insight into the clonal composition and associated mortality of BSI S. aureus isolates in Hungary. The results suggest that the outcome of the infection is determined by the antibiotic resistance, genotype of the bacterium, and patient-related factors; rather than the virulence factors carried by the bacteria.
- Published
- 2020
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32. Co-carriage of Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis among three different age categories of children in Hungary.
- Author
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Kovács E, Sahin-Tóth J, Tóthpál A, van der Linden M, Tirczka T, and Dobay O
- Subjects
- Adolescent, Age Factors, Anti-Bacterial Agents pharmacology, Child, Child, Preschool, Coinfection epidemiology, Coinfection microbiology, Female, Haemophilus Infections epidemiology, Haemophilus Infections microbiology, Humans, Hungary epidemiology, Infant, Male, Microbial Sensitivity Tests, Moraxellaceae Infections epidemiology, Moraxellaceae Infections microbiology, Pneumococcal Infections epidemiology, Pneumococcal Infections microbiology, Public Health Surveillance, Risk Factors, Serogroup, Carrier State epidemiology, Carrier State microbiology, Haemophilus influenzae classification, Haemophilus influenzae drug effects, Haemophilus influenzae genetics, Haemophilus influenzae isolation & purification, Moraxella catarrhalis classification, Moraxella catarrhalis drug effects, Moraxella catarrhalis genetics, Moraxella catarrhalis isolation & purification, Nasopharynx microbiology, Staphylococcus aureus classification, Staphylococcus aureus drug effects, Staphylococcus aureus genetics, Staphylococcus aureus isolation & purification, Streptococcus pneumoniae classification, Streptococcus pneumoniae drug effects, Streptococcus pneumoniae genetics, Streptococcus pneumoniae isolation & purification
- Abstract
Background: The nasopharynx can from time to time accommodate otherwise pathogenic bacteria. This phenomenon is called asymptomatic carriage. However, in case of decreased immunity, viral infection or any other enhancing factors, severe disease can develop. Our aim in this study was to survey the nasal carriage rates of four important respiratory pathogens in three different age groups of children attending nurseries, day-care centres and primary schools. This is the first study from Hungary about the asymptomatic carriage of H. influenzae and M. catarrhalis., Methods: Altogether 580 asymptomatic children were screened in three Hungarian cities. Samples were collected from both nostrils with cotton swabs. The identification was based on both colony morphology and species-specific PCRs. Serotyping was performed for S. pneumoniae, H. influenzae and M. catarrhalis. Antibiotic susceptibility was determined with agar dilution, according to the EUCAST guidelines. Clonality was examined by PFGE., Results and Conclusions: Whereas the carriage rates of S. pneumoniae, H. influenzae and M. catarrhalis clearly decreased with age, that of S. aureus showed an opposite tendency. Multiple carriage was least prevalent if S. aureus was one of the participants. The negative association between this bacterium and the others was statistically significant. For pneumococcus, the overall carriage rate was lower compared to earlier years, and PCV13 serotypes were present in only 6.2% of the children. The majority of H. influenzae isolates was non-typeable and no type b was detected; serotype A was dominant among M. catarrhalis. All four bacteria were more sensitive to antibiotics compared to clinical isolates. No MRSAs were detected, but we found three mupirocin resistant strains. The positive effect of Hib- and PCV-vaccination is undoubted. Continued surveillance of these pathogens is required., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2020
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33. High prevalence of group B streptococcus ST17 hypervirulent clone among non-pregnant patients from a Hungarian venereology clinic.
- Author
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Kardos S, Tóthpál A, Laub K, Kristóf K, Ostorházi E, Rozgonyi F, and Dobay O
- Subjects
- Adult, Anti-Bacterial Agents pharmacology, Bacterial Proteins genetics, DNA, Bacterial genetics, DNA, Bacterial metabolism, Drug Resistance, Bacterial drug effects, Female, Humans, Hungary epidemiology, Macrolides pharmacology, Microbial Sensitivity Tests, Phenotype, Prevalence, Serogroup, Streptococcal Infections epidemiology, Streptococcus agalactiae drug effects, Streptococcus agalactiae isolation & purification, Streptococcus agalactiae pathogenicity, Virulence genetics, Streptococcal Infections diagnosis, Streptococcus agalactiae genetics
- Abstract
Background: Although Streptococcus agalactiae is the leading causative agent of neonatal sepsis and meningitis, recently it is increasingly isolated from non-pregnant adults. The relation between its presence in the genitourinary tract and manifested clinical symptoms of STD patients remains an open question. In this study, a complex epidemiological investigation of GBS isolates from a venerology clinic was performed., Methods: Ninety-six GBS isolates were serotyped and their genetic relatedness determined by PFGE. MLST was also performed for a subset of 20 isolates. The antibiotic susceptibility was tested with agar dilution. Surface proteins and the ST-17 hypervirulent clone was detected by PCR., Results: The serotype prevalence was the following: V (29.2%), III (27.1%), Ia (22.9%), IV (10.4%), II (5.2%) and Ib (4.2%). A strong association was demonstrated between surface protein genes and serotypes. All isolates were fully susceptible to penicillin, but erythromycin and clindamycin resistance was high (41.7 and 35.4%, respectively), and 8 phenotypically macrolide sensitive isolates carried the ermB gene. 21.9% of all strains belonged to the hypervirulent ST17 clone, most being of serotype III and all were rib +. We found a few serotype IV isolates belonging to several STs and one serotype V/ST110 strain, containing a 44-bp deletion in the atr allele., Conclusions: The presence of silent ermB genes is of worry, as their expression upon macrolide exposure could lead to unforeseen therapeutic failure, while clindamycin is used for intrapartum antibiotic prophylaxis, in case of penicillin allergy. The other alarming result is the high prevalence of ST17 among these strains from STD patients, who could be sources of further infections. This is the first report from Hungary providing both serotyping and genotyping data of GBS isolates. These results could be helpful for vaccine production as the major vaccine candidates are capsular antigens or surface proteins.
- Published
- 2019
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34. Vaccine-driven serotype-rearrangement is seen with latency in clinical isolates: Comparison of carried and clinical pneumococcal isolates from the same time period in Hungary.
- Author
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Kovács E, Sahin-Tóth J, Tóthpál A, Kristóf K, van der Linden M, Tirczka T, and Dobay O
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Anti-Bacterial Agents pharmacology, Carrier State epidemiology, Child, Child, Preschool, Drug Resistance, Bacterial, Female, Heptavalent Pneumococcal Conjugate Vaccine immunology, Heptavalent Pneumococcal Conjugate Vaccine therapeutic use, Humans, Hungary epidemiology, Infant, Infant, Newborn, Male, Microbial Sensitivity Tests, Middle Aged, Nasopharynx microbiology, Pneumococcal Infections epidemiology, Pneumococcal Vaccines immunology, Pneumococcal Vaccines therapeutic use, Streptococcus pneumoniae drug effects, Young Adult, Carrier State microbiology, Pneumococcal Infections microbiology, Serogroup, Streptococcus pneumoniae classification
- Abstract
Young children - the main asymptomatic carriers of pneumococcus - are often the source of pneumococcal infections. PCV13 replaced PCV7 in 2010 in Hungary and it became a mandatory vaccine in 2014. In this work we surveyed the effect of vaccination in three groups: in healthy children under 7 years; in children of the same age but infected with pneumococcus (P1); in older patients (P2) who were very likely not vaccinated. Nasal swabs were taken from 522 healthy children to screen pneumococcal carriage between March 2015 and May 2016. In the same time period, 146 clinical isolates were collected, mainly from mucosal infections. Serotypes, antibiotic susceptibility and clonality of the isolates was determined and compared. The carriage rate was 39.1%. Regarding carriage, the serotype distribution showed the total disappearance of serotypes 3 and 6A compared to former Hungarian studies. The prevalence of PCV13 serotypes was only 5.8% represented by three serotypes (19F, 19A, 9V). Of note, serotype 19A (a very resistant and invasive type) also decreased significantly. In the patient groups, PCV13 prevalence was higher: 17.5% (P1) and 32.6% (P2). Although serotype 3 was present in P1 (7.9%), the leading serotype was 23B (22.2%), a non-vaccine type (NVT). P2 showed the most diverse serotype distribution, but serotype 3 was predominant here (15.7%). Pneumococcal isolates from the patients were more resistant towards the tested antibiotics compared to those from carriers. PCV13 seems to be highly successful in reducing the prevalence of vaccine serotypes. The serotype-rearrangement can be seen also among clinical isolates, albeit somewhat later in time. Fortunately, the replacing serotypes are less invasive and less resistant, but, most worrisome, serotype 19F can be found again with increased frequency among carriage isolates and mucosal infections. Further surveillance is needed to carefully monitor such successful, antibiotic resistant "refugees"., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2019
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35. The complexity of serotype replacement of pneumococci.
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Dobay O
- Subjects
- Anti-Bacterial Agents pharmacology, Carrier State immunology, Drug Resistance, Bacterial, Humans, Pneumococcal Infections prevention & control, Serogroup, Serotyping, Streptococcus pneumoniae drug effects, Vaccines, Conjugate immunology, Carrier State microbiology, Pneumococcal Infections immunology, Pneumococcal Vaccines immunology, Streptococcus pneumoniae classification
- Abstract
Pneumococci respond extremely rapidly to the vaccine pressure created by the conjugate vaccines (PCVs). Vaccine serotypes are disappearing, meanwhile new, often previously very rare types are emerging, and it is difficult to establish what makes certain serotypes more successful in replacement. The situation is very complex: every serotype has different antibiotic sensitivity or invasive capacity. However, despite this dynamic serotype rearrangement, the overall pneumococcal carriage rate remains quite stable, suggesting that these bacterial species can be considered as a commensal colonizer.
- Published
- 2019
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36. Bicarbonate Inhibits Bacterial Growth and Biofilm Formation of Prevalent Cystic Fibrosis Pathogens.
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Dobay O, Laub K, Stercz B, Kéri A, Balázs B, Tóthpál A, Kardos S, Jaikumpun P, Ruksakiet K, Quinton PM, and Zsembery Á
- Abstract
We investigated the effects of bicarbonate on the growth of several different bacteria as well as its effects on biofilm formation and intracellular cAMP concentration in Pseudomonas aeruginosa . Biofilm formation was examined in 96-well plates, with or without bicarbonate. The cAMP production of bacteria was measured by a commercial assay kit. We found that NaHCO
3 (100 mmol l-1 ) significantly inhibited, whereas NaCl (100 mmol l-1 ) did not influence the growth of planktonic bacteria. MIC and MBC measurements indicated that the effect of HCO 3 - is bacteriostatic rather than bactericidal. Moreover, NaHCO3 prevented biofilm formation as a function of concentration. Bicarbonate and alkalinization of external pH induced a significant increase in intracellular cAMP levels. In conclusion, HCO 3 - impedes the planktonic growth of different bacteria and impedes biofilm formation by P. aeruginosa that is associated with increased intracellular cAMP production. These findings suggest that aerosol inhalation therapy with HCO 3 - solutions may help improve respiratory hygiene in patients with cystic fibrosis and possibly other chronically infected lung diseases.- Published
- 2018
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37. High prevalence of Staphylococcus aureus nasal carriage among children in Szolnok, Hungary.
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Laub K, Tóthpál A, Kovács E, Sahin-Tóth J, Horváth A, Kardos S, and Dobay O
- Subjects
- Anti-Bacterial Agents pharmacology, Carrier State epidemiology, Carrier State microbiology, Child, Child, Preschool, Drug Resistance, Bacterial, Female, Humans, Hungary epidemiology, Male, Microbial Sensitivity Tests, Prevalence, Staphylococcal Infections epidemiology, Staphylococcus aureus classification, Staphylococcus aureus drug effects, Staphylococcus aureus genetics, Nose microbiology, Staphylococcal Infections microbiology, Staphylococcus aureus isolation & purification
- Abstract
We collected nasal samples from 1,390 healthy 3-7 years old children in Szolnok city, Hungary, in 2012. We detected 476 Staphylococcus aureus isolates from 474 children. In two occasions, two different S. aureus were isolated, based on hemolysis type and pulsed-field gel electrophoresis pattern. S. aureus carriage rate was calculated to be 34.1% similar to others studies. Male gender was found to be a risk factor for carriage by statistical analysis. Altogether, four methicillin-resistant S. aureus (MRSA) strains were detected by mecA polymerase chain reaction, which means 0.8% community-acquired MRSA prevalence among the S. aureus isolates. All MRSA strains harbored the SCCmec type IV cassette (typical for CA-MRSA) and belonged to ST45 by multilocus sequence typing. During antibiotic susceptibility testing, we measured the following resistance rates: 0.0% for mupirocin, 0.2% for ciprofloxacin, 0.6% for gentamicin and oxacillin, 3.4% for tetracycline, 9.5% for clindamycin, 10.3% for erythromycin, and 91.4% for penicillin, which are generally lower compared with Hungarian clinical isolates.
- Published
- 2018
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38. First description of a catalase-negative Staphylococcus aureus from a healthy carrier, with a novel nonsense mutation in the katA gene.
- Author
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Laub K, Kristóf K, Tirczka T, Tóthpál A, Kardos S, Kovács E, Sahin-Tóth J, Horváth A, and Dobay O
- Subjects
- Child, Child, Preschool, Female, Genotype, Humans, Hungary, Male, Microbial Sensitivity Tests, Molecular Typing, Nasal Cavity microbiology, Staphylococcus aureus drug effects, Staphylococcus aureus isolation & purification, Young Adult, Acatalasia, Carrier State microbiology, Codon, Nonsense, Staphylococcal Infections microbiology, Staphylococcus aureus enzymology, Staphylococcus aureus genetics
- Abstract
We have screened 2568 healthy individuals (mostly children) for Staphylococcus aureus and Streptococcus pneumoniae nasal carriage between 2010 and 2012. Out of the isolated 751 S. aureus strains, we found one methicillin-sensitive catalase-negative S. aureus (CNSA). Our CNSA isolate possessed a novel nonsense point mutation in the katA gene leading to early truncation of the protein product. The strain was resistant to penicillin and erythromycin, but sensitive to all other tested antibiotics and carried the enterotoxin A gene. It belonged to sequence type 5 (ST5), which is a successful, worldwide spread, usually MRSA clone. Catalase has been described as a virulence factor strictly required for nasal colonisation, and this is the first case contradicting this theory, as all previous CNSA isolates derived from infections. This is the first report of a CNSA from a symptomless carrier as well as the first occurrence in Hungary., (Copyright © 2017 Elsevier GmbH. All rights reserved.)
- Published
- 2017
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39. Epidemiology and antibiotic sensitivity of Staphylococcus aureus nasal carriage in children in Hungary.
- Author
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Laub K, Tóthpál A, Kardos S, and Dobay O
- Subjects
- Child, Child, Preschool, Drug Resistance, Bacterial, Female, Genotype, Humans, Hungary epidemiology, Male, Microbial Sensitivity Tests, Phylogeny, Staphylococcal Infections epidemiology, Staphylococcus aureus classification, Staphylococcus aureus genetics, Anti-Bacterial Agents pharmacology, Carrier State microbiology, Nose microbiology, Staphylococcal Infections microbiology, Staphylococcus aureus drug effects, Staphylococcus aureus isolation & purification
- Abstract
The aim of this study was to assess the Staphylococcus aureus nasal carriage rate in healthy children all over Hungary and to specify some risk factors, the antibiotic resistance patterns of the bacteria, and their genetic relatedness. In total, 878 children (aged 3-6 years) were screened at 21 day-care centers in 16 different cities in Hungary, between February 2009 and December 2011. Samples taken from both nostrils were cultured on blood agar, and suspected S. aureus isolates were identified by β-hemolysis, catalase positivity, clump test, and nucA PCR. Methicillin-resistant strains were screened by mecA and mecC PCR. Antibiotic susceptibility was determined by agar dilution or gradient test strips. Pulsed-field gel electrophoresis was used for genotyping. S. aureus carriage rate was found to be 21.3%, which correlates well with international data. We found no statistically significant correlation between the gender or the sibling status and S. aureus carriage. All isolates were sensitive to oxacillin, trimethoprim-sulfamethoxazole, and mupirocin. The resistance rates for erythromycin, ciprofloxacin, clindamycin, gentamicin, and tetracycline were 7.5%, 0.5%, 1.1%, 3.7%, and 4.3%, respectively. The isolates showed very high genetic diversity. In summary, carried S. aureus isolates are more sensitive to antibiotics compared with clinical isolates in Hungary, and methicillin-resistant S. aureus carriage rate is very low yet.
- Published
- 2017
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40. Life without dUTPase.
- Author
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Kerepesi C, Szabó JE, Papp-Kádár V, Dobay O, Szabó D, Grolmusz V, and Vértessy BG
- Abstract
Fine-tuned regulation of the cellular nucleotide pools is indispensable for faithful replication of Deoxyribonucleic Acid (DNA). The genetic information is also safeguarded by DNA damage recognition and repair processes. Uracil is one of the most frequently occurring erroneous bases in DNA; it can arise from cytosine deamination or thymine-replacing incorporation. Two enzyme activities are primarily involved in keeping DNA uracil-free: dUTPase (dUTP pyrophosphatase) activity that prevent thymine-replacing incorporation and uracil-DNA glycosylase activity that excise uracil from DNA and initiate uracil-excision repair. Both dUTPase and the most efficient uracil-DNA glycosylase (UNG) is thought to be ubiquitous in free-living organisms. In the present work, we have systematically investigated the genotype of deposited fully sequenced bacterial and Archaeal genomes. We have performed bioinformatic searches in these genomes using the already well described dUTPase and UNG gene sequences. For dUTPases, we have included the trimeric all-beta and the dimeric all-alpha families and also, the bifunctional dCTP (deoxycytidine triphosphate) deaminase-dUTPase sequences. Surprisingly, we have found that in contrast to the generally held opinion, a wide number of bacterial and Archaeal species lack all of the previously described dUTPase gene(s). The dut - genotype is present in diverse bacterial phyla indicating that loss of this (or these) gene(s) has occurred multiple times during evolution. We discuss potential survival strategies in lack of dUTPases, such as simultaneous lack or inhibition of UNG and possession of exogenous or alternate metabolic enzymes involved in uracil-DNA metabolism. The potential that genes previously not associated with dUTPase activity may still encode enzymes capable of hydrolyzing dUTP is also discussed. Our data indicate that several unicellular microorganisms may efficiently cope with a dut - genotype lacking all of the previously described dUTPase genes, and potentially leading to an unusual uracil-enrichment in their genomic DNA.
- Published
- 2016
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41. Radical serotype rearrangement of carried pneumococci in the first 3 years after intensive vaccination started in Hungary.
- Author
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Tóthpál A, Kardos S, Laub K, Nagy K, Tirczka T, van der Linden M, and Dobay O
- Subjects
- Child, Child, Preschool, Female, Humans, Hungary, Male, Nasopharynx microbiology, Pneumococcal Vaccines blood, Serogroup, Streptococcus pneumoniae isolation & purification, Vaccination methods, Vaccines, Conjugate classification, Pneumococcal Vaccines immunology, Streptococcus pneumoniae immunology, Vaccines, Conjugate microbiology
- Abstract
Unlabelled: Streptococcus pneumoniae is responsible for a significant amount of morbidity and mortality worldwide. Healthy carriers, mainly young children, are the most important sources of infections. In the current study, we aimed to determine the changes that have occurred since the introduction of PCV-7 in Hungary. Nasal specimens were collected from 1,022 healthy children aged 3-6 years attending day-care centres. After thorough identification, pneumococcal isolates were serotyped, and their antibiotic sensitivity was determined. The carriage rate was found to be 34.9%. A huge serotype rearrangement was detected compared to earlier results, with the previously leading serotype 14 having completely disappeared. Serotypes 11A, 35F, 19A, 6B, 15B, 3 and 38 were most prevalent, and 29 different types were identified in total. The PCV-7 types were responsible for 16.5% of all serotypes, and 36.0% are not covered by any pneumococcal vaccines. The isolates were sensitive to most tested antibiotics, except erythromycin (resistance was 21.6%). Only one penicillin-resistant strain was found. The newly and rapidly emerging non-vaccine serotypes are much more sensitive, except serotype 19A., Conclusion: Due to PCV vaccination, a complete serotype arrangement occurred also in Hungary. The old "paediatric" serotypes were replaced by serotypes 11A, 35F, 19A, 6B, 15B, 3 and 38.
- Published
- 2015
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42. Re-evaluation of in vitro activity of primycin against prevalent multiresistant bacteria.
- Author
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Feiszt P, Mestyán G, Kerényi M, Dobay O, Szabó J, Dombrádi Z, Urbán E, and Emődy L
- Subjects
- Gram-Negative Bacteria drug effects, Humans, Microbial Sensitivity Tests, Microbial Viability drug effects, Mutation, Selection, Genetic, Serial Passage, Anti-Bacterial Agents pharmacology, Drug Resistance, Multiple, Bacterial, Gram-Positive Bacteria drug effects, Macrolides pharmacology
- Abstract
With the increasing emergence of antibiotic resistances old antibiotics became a valuable source to find agents suitable to address this problem. More than 20 years after the last report, our purpose was to re-evaluate the in vitro antibacterial activity of the topical agent primycin against current important bacterial pathogens. Minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations (MBC) of primycin were tested in comparison with agents widely applied topically, and with those of mupirocin and vancomycin, the topical and the non-topical gold-standard anti-MRSA agents. Primycin was ineffective (MIC>64 μg/ml) against all the Gram-negative isolates tested. On the other hand, all the tested Gram-positive isolates were susceptible with MIC90 values of 0.06 μg/ml for staphylococci and 0.5-1 μg/ml for enterococci, streptococci, and P. acnes isolates, including all the multiresistant strains. Against MRSA isolates primycin showed slightly higher activity than mupirocin, and inhibited the mupirocin-resistant strains also. MBC90 values ranged from 0.25 to 2 μg/ml for the investigated Gram-positive species. The bactericidal effect proved to be concentration-dependent in time-kill experiments. Spontaneous resistant mutants did not emerge in single-step mutation experiments and the resistance development was very slow by serial passaging. Passaged S. aureus strains showing increased primycin MIC values exhibited elevated vancomycin and daptomycin MIC values also. Though elucidation of the mechanisms behind warrants further investigations, these correlations can be related to development of vancomycin-intermediate phenotype. From the point of view of medical practice it is noteworthy that the increased primycin MIC values remained far below the concentration accessible by local application of the agent. These data make primycin a remarkable object of further investigations as well as a promising candidate for topical application against multiresistant Gram-positive pathogens., (Copyright © 2014 Elsevier GmbH. All rights reserved.)
- Published
- 2014
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43. Changes in the serotypes of Hungarian pneumococci isolated mainly from invasive infections: a review of all available data between 1988 and 2011.
- Author
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Tóthpál A, Laub K, Kardos S, Nagy K, and Dobay O
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Child, Child, Preschool, Female, Humans, Hungary epidemiology, Infant, Male, Middle Aged, Pneumococcal Infections epidemiology, Pneumococcal Infections prevention & control, Pneumococcal Vaccines administration & dosage, Pneumococcal Vaccines genetics, Serotyping, Streptococcus pneumoniae genetics, Young Adult, Pneumococcal Infections microbiology, Streptococcus pneumoniae classification, Streptococcus pneumoniae isolation & purification
- Abstract
Streptococcus pneumoniae is responsible for a high level of morbidity and mortality, especially among children. For a long time, only the polysaccharide vaccine was available against pneumococcal infections, but in the last decade special conjugate vaccines were developed for paediatric use. These vaccines have made a deep impact on serotype distribution all over the world, by suppressing those serotypes included in the vaccines, while new, previously rare types emerged. These changes have been monitored closely in numerous publications all over the world. Nevertheless, data on pneumococcal serotypes in Hungary were mostly published in Hungarian, therefore not available in the international literature. In this meta-analysis, our aim was to collect and summarise all available data, and try to follow the changes observed after the introduction of the conjugate vaccines.
- Published
- 2012
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44. [Drastic changes in serotypes of carried pneumococci due to an increased vaccination rate in Hungary].
- Author
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Tóthpál A and Dobay O
- Subjects
- Carrier State, Humans, Hungary, Infant, Mass Vaccination statistics & numerical data, Nose microbiology, Pneumococcal Infections immunology, Pneumococcal Vaccines immunology, Streptococcus pneumoniae isolation & purification, Vaccines, Conjugate administration & dosage, Mass Vaccination trends, Pneumococcal Infections prevention & control, Pneumococcal Vaccines administration & dosage, Serotyping, Streptococcus pneumoniae immunology
- Abstract
Unlabelled: Introduction of the conjugate pneumococcal vaccine into the voluntary childhood vaccine program in Hungary in April 2009 resulted in a sharp increase of the vaccination rate. However, changes in serotypes as a consequence of vaccination should be considered., Aims: The aim of the authors was to compare pneumococci isolated from children with high-level and low-level vaccination rates., Methods: Nasal specimens from 854 children attending 20 nurseries at various locations in Hungary have been collected since 2009. The serotypes, antibiotic susceptibility and genetic relatedness of the isolated pneumococci were determined., Results: 324 strains were isolated, and the carriage rate was 37.94%. The strains were sensitive to most antibiotics, except for macrolides. A definite suppression of vaccine types was detected during these 3 years, from the initial 78.85% to 35.30%., Conclusions: The authors conclude that the results reflect the efficacy of the vaccine, which underlines the need for the inclusion of pneumococcal vaccine into the list of obligatory vaccines.
- Published
- 2012
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45. Nasal carriage of Streptococcus pneumoniae among Hungarian children before the wide use of the conjugate vaccine.
- Author
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Tóthpál A, Kardos S, Hajdú E, Nagy K, Linden M, and Dobay O
- Subjects
- Child, Child, Preschool, Female, Humans, Hungary, Male, Vaccination, Vaccines, Conjugate immunology, Carrier State microbiology, Nose microbiology, Pneumococcal Vaccines immunology, Streptococcus pneumoniae isolation & purification
- Abstract
Streptococcus pneumoniae is responsible for a significant amount of morbidity and mortality worldwide, especially among children <5 years. Healthy carriers are the most important sources of infections and the carriage also peaks in the first years of life, especially among children attending communities. In this study, for the first time in Hungary, we surveyed the nasal carriage of healthy children, just before the use of the conjugate vaccine started increasing.Nasal specimens of 358 children were cultured and pneumococci isolated. The strains were serotyped with antisera and PCR, genotyped by PFGE and their antibiotic sensitivity determined by agar dilution method.The carriage rate was 37.71%. The isolates were sensitive to most tested antibiotics, except for macrolides. In this cohort of specimens still the widespread, so-called "pediatric serotypes" dominated (14, 19F, 23F, 6A, 6B in ranking order), but three of the previously rare types: 15B, 11A and 13 were represented already by 21.5% of all strains and also a few other rare non-vaccine types (e.g. 10A or 37) were detected.The calculated vaccine coverage was 55.6% for PCV-7, 69.6% for PCV-13 and 86.7% for Pneumovax. In this cohort, only 15.9% of the children (n = 57) were vaccinated. The carriage rate of PCV-7 vaccinated children was significantly lower (30.4%) than that of the non-vaccinated group (39.2%). The clonality of the isolates was significant within each group, revealing the extensive bacterium exchange among children.
- Published
- 2012
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46. Prevalence of vanC vancomycin-resistant enterococci in the teaching hospitals of the University of Debrecen, Hungary.
- Author
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Dombrádi Z, Dobay O, Nagy K, Kozák A, Dombrádi V, and Szabó J
- Subjects
- Cross Infection epidemiology, Cross Infection microbiology, Electrophoresis, Gel, Pulsed-Field, Enterococcus drug effects, Enterococcus isolation & purification, Gentamicins pharmacology, Hospitals, Teaching, Humans, Hungary epidemiology, Longitudinal Studies, Microbial Sensitivity Tests, Multiplex Polymerase Chain Reaction, Phylogeny, Prevalence, Anti-Bacterial Agents pharmacology, Bacterial Proteins genetics, Cross Infection drug therapy, Enterococcus genetics, Genes, Bacterial, Vancomycin pharmacology, Vancomycin Resistance genetics
- Abstract
Vancomycin-resistant enterococci (VRE) are common nosocomial pathogens; however, until now they have been rarely encountered in Hungary. In the present study, we investigated the prevalence of VRE in the teaching hospitals of the University of Debrecen. Of 7,271 Enterococcus-containing clinical samples collected between 2004 and 2009, we identified 16 VRE. Species-specific polymerase chain reaction was used to detect Enterococcus faecalis, Enterococcus faecium, Enterococcus casseliflavus, and Enterococcus gallinarum. Multiplex polymerase chain reaction was performed to identify the vancomycin resistance genes: vanA, vanB, vanC1/C2, vanD, vanE, and vanG. Restriction digestion with SalI and HindIII was introduced to differentiate the vanC1 and vanC2 genes from each other. Genetic relationships between the strains were investigated by pulsed-field gel electrophoresis. Overall, we identified the vanC1 resistance gene in 14 E. gallinarum and the vanC2 resistance gene in two E. casseliflavus strains. Except for two samples, the isolates had different pulsed-field gel electrophoresis types, suggesting sporadic emergence of the resistant bacteria. In addition, antibiotic resistance profile was determined by E-test. Three E. gallinarum strains proved to be resistant to gentamicin because of the presence of the aacA-aphD gene. Although the prevalence of VRE in Debrecen is rather low, the appearance of multiple resistances is of concern.
- Published
- 2012
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47. A marked shift in the serotypes of pneumococci isolated from healthy children in Szeged, Hungary, over a 6-year period.
- Author
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Tóthpál A, Ordas A, Hajdú E, Kardos S, Nagy E, Nagy K, and Dobay O
- Subjects
- Anti-Bacterial Agents pharmacology, Carrier State microbiology, Child, Child Day Care Centers, Child, Preschool, Drug Resistance, Bacterial drug effects, Electrophoresis, Gel, Pulsed-Field, Female, Humans, Hungary epidemiology, Male, Microbial Sensitivity Tests, Pneumococcal Infections microbiology, Prevalence, Serotyping, Streptococcus pneumoniae classification, Streptococcus pneumoniae pathogenicity, Vaccines, Conjugate administration & dosage, Pneumococcal Infections epidemiology, Pneumococcal Vaccines administration & dosage, Streptococcus pneumoniae isolation & purification
- Abstract
Streptococcus pneumoniae is an important pathogen with significant morbidity and mortality rates worldwide, especially among children <5 years. Healthy carriers are the most important sources of pneumococcal infections, and the nasopharyngeal colonisation is the most prevalent among children attending communities such as day-care centres (DCCs). The conjugate pneumococcal vaccines (PCVs) were shown to have an impact on the colonisation, and so play an important role in inhibiting infections. In this study we compared the nasal carriage of healthy children attending DCCs in Szeged, Hungary in 2003/2004, when nobody was vaccinated, and in 2010, when already 1/5 of the children received PCV-7. Significant differences were observed in the serotype distribution, representing a marked shift from the previously widespread vaccine-types (mostly 6A or 14) to others (11A and 23F). The new serotypes showed higher antibiotic susceptibility. The bacterium exchange between children was clear from the pulsed-field gel electrophoresis (PFGE) patterns, and the circulation of certain international clones plays also a role in these dynamic changes.
- Published
- 2011
- Full Text
- View/download PDF
48. Detection of Staphylococcus aureus nasal carriage in healthy young adults from a Hungarian University.
- Author
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Laub K, Kardos S, Nagy K, and Dobay O
- Subjects
- Anti-Bacterial Agents pharmacology, Carrier State epidemiology, Electrophoresis, Gel, Pulsed-Field methods, Humans, Hungary epidemiology, Microbial Sensitivity Tests methods, Prevalence, Risk Factors, Staphylococcal Infections epidemiology, Students, Universities, Young Adult, Carrier State microbiology, Nose microbiology, Staphylococcal Infections microbiology, Staphylococcus aureus genetics, Staphylococcus aureus isolation & purification
- Abstract
Asymptomatic carriage of Staphylococcus aureus in healthy individuals has a high prevalence, especially in children and young adults. Nasal colonisation is a well-known risk factor for subsequent severe infection, or can be the source of transmission of this bacterium to other susceptible persons. In this study, we have surveyed the nasal carriage rate of students of the Semmelweis University, by screening 300 volunteers. We have determined the antibiotic sensitivity of the isolates by Etest, and their genetic relatedness by pulsed-fieled gel electrophoresis. The nasal carriage rate of S. aureus was found to be 29.3%, and that of MRSA only 0.67% (2/300). The isolates were generally sensitive to antibiotics, except for macrolides. We could observe a noticeably great genetic diversity, even among strains deriving from students of the same university group.
- Published
- 2011
- Full Text
- View/download PDF
49. Taguchi optimisation of a multiplex pneumococcal serotyping PCR and description of 11 novel serotyping primers.
- Author
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Dobay O, Juhász E, Ungvári A, Jeney C, Amyes SG, and Nagy K
- Subjects
- Base Sequence, Humans, Molecular Sequence Data, Sequence Alignment, Species Specificity, Streptococcus pneumoniae classification, Streptococcus pneumoniae genetics, DNA Primers genetics, Pneumococcal Infections microbiology, Polymerase Chain Reaction methods, Serotyping methods, Streptococcus pneumoniae isolation & purification
- Abstract
Recently, a PCR-derived method for serotyping Streptococcus pneumoniae has been devised to substitute the conventional antiserum phenotypic method. The method initially used a multiplex PCR reaction, dividing the isolates into 6 different groups based on the detected PCR gel pattern. In order to optimise and refine this crucial step, the Taguchi technique was employed, which can evaluate the individual effect of six parameters (in this case: primers, MgCl2, nucleotide mix, polymerase and buffer), with only 18 experiments; varying the parameter levels in an orthogonal matrix which suppresses the interactions between them. With this method, clear and sharp bands were observed in 5 experiments out of the 18, while the PCR did not work reliably in the remaining cases. In addition, the PCR-based technique could be rendered more economic by the 10-fold lowering of the quantities of two primers. The modified reaction yielded identical results to those obtained with the original method. Furthermore, we have designed serotype-specific primers for 11 new serotypes. The most important ones are those that can distinguish the very closely related, but equally important serotypes 6A and 6B.
- Published
- 2009
- Full Text
- View/download PDF
50. Vancomycin resistant enterococci (VRE) still persist in slaughtered poultry in hungary 8 years after the ban on avoparcin.
- Author
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Ghidán A, Dobay O, Kaszanyitzky EJ, Samu P, Amyes SG, Nagy K, and Rozgonyi F
- Subjects
- Animal Husbandry standards, Animals, Anti-Bacterial Agents administration & dosage, Anti-Bacterial Agents adverse effects, Bacterial Proteins genetics, Carbon-Oxygen Ligases genetics, Enterococcus faecalis classification, Enterococcus faecalis genetics, Enterococcus faecalis isolation & purification, Enterococcus faecium classification, Enterococcus faecium genetics, Enterococcus faecium isolation & purification, Glycopeptides administration & dosage, Glycopeptides adverse effects, Gram-Positive Bacterial Infections prevention & control, Humans, Hungary epidemiology, Intestines microbiology, Microbial Sensitivity Tests, Animal Husbandry organization & administration, Enterococcus faecalis drug effects, Enterococcus faecium drug effects, Poultry microbiology, Vancomycin pharmacology, Vancomycin Resistance genetics
- Abstract
In this report we examined the glycopeptide susceptibility of enterococci, isolated in 2005, from slaughtered animals, within the confines of Hungarian Antibiotic Resistance Monitoring System. We determined the presence of the van genes as well as their genetic relatedness in enterococci from poultry. Enterococcus sp. strains (n=175) were collected from intestinal samples of slaughtered poultry in 2005. The origin of the samples was registered at county level. After screening the strains with 30 mg vancomycin disc 19 (86%) intermediate resistant and 4 (3%) fully resistant strains were found. The distribution of minimum inhibitory concentration (MIC)-values among 23 enterococcus strains which were intermediate or resistant to vancomycin were 0.25 mg/L (4.4%), 2 mg/L (8.6%), 4 mg/L (8.6%), 8 mg/L (61%), 16 mg/L (8.6%) and 256 mg/L (8.6%). The MICs of teicoplanin were 0.25 mg/L (4.3%), 1 (8.6%), 4 mg/L (78.3%), 16 mg/L (4.3%) and 256 mg/L (4.3%). The two most vancomycin-resistant strains were vanA carriers (1 E. faecalis and 1 E. faeciuum). The farms that produced these strains can be reservoirs of VRE and the affected farms should change the technology of disinfection and breeding in order to prevent the emergence of high numbers of human VRE isolates in Hungary.
- Published
- 2008
- Full Text
- View/download PDF
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