@article{MTMT:34779051,
	title = {Resistome analysis of Escherichia coli isolates from layers in Hungary},
	url = {https://m2.mtmt.hu/api/publication/34779051},
	author = {Kerek, Ádám and Szabó, Ábel and Bányai, Krisztián and Kaszab, Eszter and Bali, Krisztina and Papp, Márton and Kovács, László and Jerzsele, Ákos},
	doi = {10.1556/004.2024.00988},
	journal-iso = {ACTA VET HUNG},
	journal = {ACTA VETERINARIA HUNGARICA},
	volume = {72},
	unique-id = {34779051},
	issn = {0236-6290},
	abstract = {The authors aimed to investigate eight strains of Escherichia coli ( E. coli ) strains from Hungarian layer flocks for antimicrobial resistance genes (ARG), using metagenomic methods. The strains were isolated from cloacal swabs of healthy adult layers. This study employed shotgun sequencing-based genetic and bioinformatic analysis along with determining phenotypic minimum inhibitory concentrations. A total of 59 ARGs were identified in the eight  E. coli isolates, carrying ARGs against 15 groups of antibiotics. Among these, 28 ARGs were identified as transferable. Specifically, four ARGs were plasmid-derived, 18 ARGs were phage-derived and an additional six ARGs were predicted to be mobile, contributing to their mobility and potential spread between bacteria.},
	year = {2024},
	eissn = {1588-2705},
	pages = {1-10},
	orcid-numbers = {Papp, Márton/0000-0003-4975-253X}
}

@article{MTMT:34726727,
	title = {In Vitro Microevolution and Co-Selection Assessment of Amoxicillin and Cefotaxime Impact on Escherichia coli Resistance Development},
	url = {https://m2.mtmt.hu/api/publication/34726727},
	author = {Kerek, Ádám and Török, Bence and Laczkó, Levente and Somogyi, Zoltán and Kardos, Gábor and Bányai, Krisztián and Kaszab, Eszter and Bali, Krisztina and Jerzsele, Ákos},
	doi = {10.3390/antibiotics13030247},
	journal-iso = {ANTIBIOTICS-BASEL},
	journal = {ANTIBIOTICS},
	volume = {13},
	unique-id = {34726727},
	abstract = {The global spread of antimicrobial resistance has become a prominent issue in both veterinary and public health in the 21st century. The extensive use of amoxicillin, a beta-lactam antibiotic, and consequent resistance development are particularly alarming in food-producing animals, with a focus on the swine and poultry sectors. Another beta-lactam, cefotaxime, is widely utilized in human medicine, where the escalating resistance to third- and fourth-generation cephalosporins is a major concern. The aim of this study was to simulate the development of phenotypic and genotypic resistance to beta-lactam antibiotics, focusing on amoxicillin and cefotaxime. The investigation of the minimal inhibitory concentrations (MIC) of antibiotics was performed at 1×, 10×, 100×, and 1000× concentrations using the modified microbial evolution and growth arena (MEGA-plate) method. Our results indicate that amoxicillin significantly increased the MIC values of several tested antibiotics, except for oxytetracycline and florfenicol. In the case of cefotaxime, this increase was observed in all classes. A total of 44 antimicrobial resistance genes were identified in all samples. Chromosomal point mutations, particularly concerning cefotaxime, revealed numerous complex mutations, deletions, insertions, and single nucleotide polymorphisms (SNPs) that were not experienced in the case of amoxicillin. The findings suggest that, regarding amoxicillin, the point mutation of the acrB gene could explain the observed MIC value increases due to the heightened activity of the acrAB-tolC efflux pump system. However, under the influence of cefotaxime, more intricate processes occurred, including complex amino acid substitutions in the ampC gene promoter region, increased enzyme production induced by amino acid substitutions and SNPs, as well as mutations in the acrR and robA repressor genes that heightened the activity of the acrAB-tolC efflux pump system. These changes may contribute to the significant MIC increases observed for all tested antibiotics. The results underscore the importance of understanding cross-resistance development between individual drugs when choosing clinical alternative drugs. The point mutations in the mdtB and emrR genes may also contribute to the increased activity of the mdtABC-tolC and emrAB-tolC pump systems against all tested antibiotics. The exceptionally high mutation rate induced by cephalosporins justifies further investigations to clarify the exact mechanism behind.},
	year = {2024},
	eissn = {2079-6382}
}

@article{MTMT:34714412,
	title = {Susceptibility of Actinobacillus pleuropneumoniae, Pasteurella multocida and Streptococcus suis Isolated from Pigs in Hungary between 2018 and 2021},
	url = {https://m2.mtmt.hu/api/publication/34714412},
	author = {Somogyi, Zoltán and Mag, Patrik and Simon, Reka and Kerek, Ádám and Makrai, László and Biksi, Imre and Jerzsele, Ákos},
	doi = {10.3390/antibiotics12081298},
	journal-iso = {ANTIBIOTICS-BASEL},
	journal = {ANTIBIOTICS},
	volume = {12},
	unique-id = {34714412},
	abstract = {Porcine respiratory disease complex (PRDC) has been a major animal health, welfare, and economic problem in Hungary; therefore, great emphasis should be put on both the prevention and control of this complex disease. As antibacterial agents are effective tools for control, antibiotic susceptibility testing is indispensable for the proper implementation of antibacterial therapy and to prevent the spread of resistance. The best method for this is to determine the minimum inhibitory concentration (MIC) by the broth microdilution method. In our study, we measured the MIC values of 164 Actinobacillus pleuropneumoniae, 65 Pasteurella multocida, and 118 Streptococcus suis isolates isolated from clinical cases against the following antibacterial agents: amoxicillin, ceftiofur, cefquinome, oxytetracycline, doxycycline, tylosin, tilmicosin, tylvalosin, tulathromycin, lincomycin, tiamulin, florfenicol, colistin, enrofloxacin, and sulfamethoxazole-trimethoprim. Outstanding efficacy against A. pleuropneumoniae isolates was observed with ceftiofur (100%) and tulathromycin (100%), while high levels of resistance were observed against cefquinome (92.7%) and sulfamethoxazole-trimethoprim (90.8%). Ceftiofur (98.4%), enrofloxacin (100%), florfenicol (100%), and tulathromycin (100%) were found to be highly effective against P. multocida isolates, while 100% resistance was detected against the sulfamethoxazole-trimethoprim combination. For the S. suis isolates, only ceftiofur (100%) was not found to be resistant, while the highest rate of resistance was observed against the sulfamethoxazole-trimethoprim combination (94.3%). An increasing number of studies report multi-resistant strains of all three pathogens, making their monitoring a high priority for animal and public health.},
	keywords = {DISEASE; RESISTANCE; ESCHERICHIA-COLI; UNITED-STATES; Antimicrobial susceptibility; MIC; Antibacterial agents; Actinobacillus pleuropneumoniae; Infectious Diseases; Pasteurella multocida; Streptococcus suis; EDIBLE TISSUES},
	year = {2023},
	eissn = {2079-6382}
}

@article{MTMT:34516912,
	title = {Determining the In Vivo Efficacy of Plant-Based and Probiotic-Based Antibiotic Alternatives against Mixed Infection with Salmonella enterica and Escherichia coli in Domestic Chickens},
	url = {https://m2.mtmt.hu/api/publication/34516912},
	author = {Kerek, Ádám and Szabó, Á. and Dobra, Péter Ferenc and Bárdos, K. and Ózsvári, László and Fehérvári, Péter and Bata, Z. and Molnár-Nagy, V. and Jerzsele, Ákos},
	doi = {10.3390/vetsci10120706},
	journal-iso = {VET SCI},
	journal = {VETERINARY SCIENCES},
	volume = {10},
	unique-id = {34516912},
	issn = {2306-7381},
	abstract = {Restrictions on the use of antimicrobial compounds have led to a surge of interest in alternative solutions, such as natural, plant-based compounds. In our study, we investigated the efficacy of three feed supplements containing different additives, namely, probiotics (Lactobacillus spp., “Test substance A”), turmeric (Curcuma longa L., “Test substance B”), and fenugreek (Trigonella foenum graecum, “Test substance C”). In the experiment, we tested 180 birds of the Bábolna Tetra-SL laying hybrid breed that were infected with Salmonella enteritidis strains. The birds were randomly divided into six groups: three groups treated with the different additives, a negative control group, a positive control group, and an antibiotic-treated group using enrofloxacin. We examined the maturation and the time course of shedding of Salmonella; at the end of rearing, pathological and histopathological examinations were performed. When Salmonella was isolated from the cloacal swab samples, the enrofloxacin-treated group had a high number of animals shedding Salmonella by day 9, which was like the group treated with test material C. The greatest reduction in Salmonella shedding was observed in the groups treated with test materials A and B. In terms of pathological parameters, villus length and crypt depth were significantly better in the group treated with test material C compared to the positive and negative controls, and when comparing the body weight of the tested animals, the group treated with test material B had a significantly larger absorption surface area compared to the positive control group. Overall, the supplement with test material C proved to be the most effective. In the future, it is worthwhile to investigate the combination of the tested active substances for their possible synergistic effects and to perform a dose-response study to select the optimal dosage. © 2023 by the authors.},
	keywords = {Body Weight; ARTICLE; Triticum aestivum; Triticum aestivum; Escherichia coli; controlled study; nonhuman; dose response; animal tissue; animal model; animal experiment; Histopathology; pathology; Histology; diet supplementation; antibiotic agent; Salmonella enteritidis; bacterial strain; Small intestine; optimal drug dose; colony forming unit; health hazard; egg laying; hen; Gallus gallus; Surface area; Probiotics; Cloaca; Synergistic effect; Escherichia coli infection; body weight gain; Curcuma longa; typhoid fever; bacterial shedding; Curcuma longa extract; Lactobacillus casei; fenugreek; Laying hens; Enrofloxacin; Antibiotic alternatives; Salmonella enterica serovar Enteritidis; fenugreek extract; Trigonella foenum graecum; Curcuma longaL; Bifidobacterium breve extract; Lactobacillus casei extract},
	year = {2023}
}

@article{MTMT:34436855,
	title = {In Vitro Microevolution and Co-Selection Assessment of Florfenicol Impact on Escherichia coli Resistance Development},
	url = {https://m2.mtmt.hu/api/publication/34436855},
	author = {Kerek, Ádám and Török, Bence and Laczkó, Levente and Kardos, Gábor and Bányai, Krisztián and Somogyi, Zoltán and Kaszab, Eszter and Bali, Krisztina and Jerzsele, Ákos},
	doi = {10.3390/antibiotics12121728},
	journal-iso = {ANTIBIOTICS-BASEL},
	journal = {ANTIBIOTICS},
	volume = {12},
	unique-id = {34436855},
	abstract = {The issue of antimicrobial resistance is becoming an increasingly serious challenge in both human and veterinary medicine. Prudent antimicrobial use in veterinary medicine is warranted and supported by international guidelines, with the Antimicrobial Advice Ad Hoc Expert Group (AMEG) placing particular emphasis on the critically important group B antimicrobials. These antimicrobials are commonly employed, especially in the poultry and swine industry. The impact of florfenicol, a veterinary antibiotic, was studied on the resistance development of Escherichia coli. The aim of the study was to investigate the effect of the use of florfenicol on the development of phenotypic and genomic resistances, not only to the drug itself but also to other drugs. The minimum inhibitory concentrations (MICs) of the antibiotics were investigated at 1×, 10×, 100× and 1000× concentrations using the adapted Microbial Evolution and Growth Arena (MEGA-plate) method. The results demonstrate that florfenicol can select for resistance to fluoroquinolone antibiotics (167× MIC value increase) and cephalosporins (67× MIC value increase). A total of 44 antimicrobial resistance genes were identified, the majority of which were consistent across the samples. Chromosomal point mutations, including alterations in resistance-associated and regulatory genes (acrB, acrR, emrR and robA), are thought to trigger multiple drug efflux pump activations, leading to phenotypically increased resistance. The study underscores the impact of florfenicol and its role in the development of antimicrobial resistance, particularly concerning fluoroquinolone antibiotics and cephalosporins. This study is the first to report florfenicol’s dose-dependent enhancement of other antibiotics’ MICs, linked to mutations in SOS-box genes (mdtABC-tolC, emrAB-tolC and acrAB-tolC) and increased multidrug efflux pump genes. Mutations in the regulatory genes acrR, emrR and rpbA support the possibility of increased gene expression. The results are crucial for understanding antimicrobial resistance and its development, highlighting the promising potential of in vitro evolutionary and coselection studies for future research.},
	year = {2023},
	eissn = {2079-6382},
	pages = {1728-1746}
}

@article{MTMT:34125170,
	title = {In Vitro Efficacy of Hungarian Propolis against Bacteria, Yeast, and Trichomonas gallinae Isolated from Pigeons—A Possible Antibiotic Alternative?},
	url = {https://m2.mtmt.hu/api/publication/34125170},
	author = {Kerek, Ádám and Csanády, Péter and Tuska-Szalay, Barbara and Kovács, László and Jerzsele, Ákos},
	doi = {10.3390/resources12090101},
	journal-iso = {RESOURCES-BASEL},
	journal = {RESOURCES (BASEL)},
	volume = {12},
	unique-id = {34125170},
	abstract = {The spread of antimicrobial resistance is one of the most serious human and animal health problems of our time. Propolis is a natural substance with antibacterial, antifungal, and antiparasitic activity, the most active components of which are polyphenols and terpenoids. In the present study, the authors investigated the efficacy of propolis against Staphylococcus spp., Enterococcus spp., Escherichia coli and Salmonella enterica, Candida albicans fungi, and Trichomonas gallinae isolated from pigeons. For each pathogen, the minimum inhibitory concentration (MIC) and minimum eradication concentration (MEC) of eight isolates were determined for 96%, 90%, 80%, 70%, and 60% ethanolic extracts of propolis from the region of Észak-Alföld. Propolis was shown to be effective in inhibiting the growth of Gram-positive bacteria, Candida albicans, and Trichomonas gallinae strains. Propolis showed a much better efficacy against Gram-positive bacteria (1.56–400 µg/mL) than against Gram-negative bacteria (>13,000 µg/mL). For Staphylococcus spp., MIC values ranged within 1.56–400 µg/mL and MEC values within 12.5–3260 µg/mL, while for Enterococcus spp. MIC values ranged within 1.56–400 µg/mL and MEC values within 12.5–800 µg/mL. MIC values > 13,000 µg/mL were found for Escherichia coli and Salmonella enterica species. For Candida albicans, MIC values ranging from 1.56 to 400 µg/mL and MEC values ranging from 3.125 to 800 µg/mL were effective. MEC values between 2.5 and 5 mg/mL were observed for three Trichomonas gallinae strains. The effectiveness against Gram-positive bacteria has, in some cases, approached that of antibiotics, making propolis a potential alternative in the treatment of wound infections. Its outstanding efficacy against Trichomonas gallinae holds promise as a potential alternative for treating this widespread infection in pigeons.},
	year = {2023},
	eissn = {2079-9276},
	pages = {101}
}

@article{MTMT:34113765,
	title = {A propolisz különböző kivonatainak in vivo hatékonysága brojlercsirke szalmonellózisa esetén},
	url = {https://m2.mtmt.hu/api/publication/34113765},
	author = {Olasz, Ákos and Jerzsele, Ákos and Balta, László and Dobra, Péter Ferenc and Kerek, Ádám},
	doi = {10.56385/magyallorv.2023.08.461-475},
	journal-iso = {MAGY ALLATORVOSOK},
	journal = {MAGYAR ÁLLATORVOSOK LAPJA},
	volume = {145},
	unique-id = {34113765},
	issn = {0025-004X},
	abstract = {A terjedő antimikrobiális rezisztencia következtében egyre nagyobb hangsúlyt kap az antibiotikumalternatívák fejlesztése és alkalmazása. Ilyen pl. a propolisz, amely a méhek által készített természetes bakteriosztatikus vagy baktericid hatásmódú anyag. Vizsgálatukban a szerzők a propolisz brojlercsirkék szalmonellózisának megelőzésében és kezelésében betöltött lehetséges szerepét vizsgálták. Kimutatták, hogy a propolisz szignifikánsan nem befolyásolja a testtömeg-gyarapodást, ill. a fajlagos takarmányértékesítést a kontrollhoz képest, de csökkenti a szalmonellózis megeredésének esélyét. Kijelenthető, hogy a propolisz biztonságosan alkalmazható takarmánykiegészítő brojlercsirkék számára.},
	year = {2023},
	pages = {461-475}
}

@article{MTMT:34113287,
	title = {Gyógynövényekből kivont illóolajok antimikrobiális spektruma – állategészségügyi vonatkozások},
	url = {https://m2.mtmt.hu/api/publication/34113287},
	author = {Kovács, László and Nagy, Dominika and Könyves, László and Jerzsele, Ákos and Kerek, Ádám},
	doi = {10.56385/magyallorv.2023.08.497-510},
	journal-iso = {MAGY ALLATORVOSOK},
	journal = {MAGYAR ÁLLATORVOSOK LAPJA},
	volume = {145},
	unique-id = {34113287},
	issn = {0025-004X},
	abstract = {Az antimikrobiális szerekkel szembeni rezisztencia terjedése egyre növekvő köz- és állategészségügyi problémát jelent. Az Egy Egészség elve szerint a figyelem egyre inkább az alternatív megoldások felé irányul. Ezek egyik fő területe a gyógynövényekből kivonható illóolajok antimikrobiális hatékonyságának vizsgálata, amelyek kiválthatják az antibiotikumok használatát. Ezen túlmenően az illóolajok és az antibiotikumok együttes használata során azok szinergista vagy additív hatása is ma már tudományosan bizonyított. A szerzők jelen irodalmi összefoglalóban szakirodalmi adatok alapján bemutatják az egyes gyógynövények és a belőlük kivont illóolajok antimikrobiális hatékonyságát.},
	year = {2023},
	pages = {497-510}
}

@article{MTMT:34087634,
	title = {Microbial evolution and growth arena (MEGA-plate), accelerated evolution and co-selection studies with Escherichia coli strains for extended spectrum beta-lactamase (ESBL) production},
	url = {https://m2.mtmt.hu/api/publication/34087634},
	author = {Kerek, Ádám and Torok, B. and Jerzsele, Ákos},
	doi = {10.1111/jvp.13292},
	journal-iso = {J VET PHARMACOL THER},
	journal = {JOURNAL OF VETERINARY PHARMACOLOGY AND THERAPEUTICS},
	volume = {46},
	unique-id = {34087634},
	issn = {0140-7783},
	keywords = {Pharmacology & Pharmacy},
	year = {2023},
	eissn = {1365-2885},
	pages = {91-91}
}

@article{MTMT:34087329,
	title = {Metagenomic analysis of veterinary probiotics in broiler chickens},
	url = {https://m2.mtmt.hu/api/publication/34087329},
	author = {Kerek, Ádám and Roman, I and Jerzsele, Ákos},
	doi = {10.1111/jvp.13295},
	journal-iso = {J VET PHARMACOL THER},
	journal = {JOURNAL OF VETERINARY PHARMACOLOGY AND THERAPEUTICS},
	volume = {46},
	unique-id = {34087329},
	issn = {0140-7783},
	keywords = {Pharmacology & Pharmacy},
	year = {2023},
	eissn = {1365-2885},
	pages = {92-93}
}