Antibiotic resistance is one of the most important public health problem and one of the most critical steps in preventing resistance is the monitorization of the resistance. Local, regional and global monitoring enables the spread of antibiotic resistance to be understood more clearly. In this study, it was aimed to evaluate the results of the pilot study for the establishment of molecular-based carbapenem surveillance system in Escherichia coli and Klebsiella pneumoniae isolates and to investigate the carbapenemase epidemiology in Turkey. Hospitals (n= 28) from 26 different statistical level II regions from Turkey were included in the study. The hospitals participated in the study submitted ten carbapenem susceptible and ten carbapenem resistant E.coli and K.pneumoniae isolates to our laboratory that were isolated in two different periiods of six-month either between 1 March-31 August or 1 April-30 September 2019. A total of 509 isolates were collected from 26 of the 28 participating hospitals in the study. Isolates were identified by matrix assisted laser desorptionization-time of flight mass spectrophotometry (MALDI TOF MS) (Bruker Daltonics, Germany) method and antibiotic susceptibility tests for imipenem, meropenem and colistin were studied by broth microdilution. Moreover, susceptibilities to amikacin, amoxicillin-clavulanic acid, ampicillin, aztreonam, cefepime, cefotaxime, ceftazidime, ciprofloxacin, ertapenem, gentamicin, piperacillin-tazobactam, tobramycin and trimethoprim-sulfamethoxazole were determined by disc diffusion method. The resistance genes were investigated in isolates which were found to be phenotypically resistant to carbapenem and colistin, in house method was used to investigate carbapenemase genes and a commercial colistin resistant real-time PCR kit (Biospeedy, Turkey) was used for colistin resistance genes. In total, 493 of the 509 isolates collected from hospitals were identified as E.coli (25.7%, n= 127) and K.pneumoniae (74.3%, n= 366) and included in the study. It was determined that 31% of the isolates evaluated were from community-acquired infections and 69% were either from healthcare-associated infections or from colonization sites. Among the tested isolates, 248 (50.3%) were susceptible to carbapenems and 245 (49.7%) were resistant. The types of carbapenemases in carbapenemase-producing isolates were OXA-48 (52.2%), KPC (16.1%), NDM-1 (15%), OXA-48 + NDM-1 (12.6%), KPC + NDM-1 (2.8%) and VIM (0.5%) and OXA-48+VIM (0.5%). Resistance to colistin was detected in 23.3% of the isolates but mcr1-8 genes were not detected. It was found that all colistin resistant isolates are resistant to at least one of the carbapenems. The importance of a molecular-based antimicrobial resistance surveillance system in our country was demonstrated with this pilot study. It is thought that continuous monitoring of these epidemiological features will contribute to the management of infections due to carbapenemase-producing organisms.

The present study aims to characterize twenty-seven Staphylococcus aureus isolates among a total of forty-four Staphylococci recovered from raw milk and traditional artisanal dairy foods (n = 285) in Central Anatolia and the Mediterranean Regions of Turkey, using MALDI-TOF MS-based phyloproteomic principal component analysis (PCA). The data shown by the spectra were analyzed, followed by composite correlation index (CCI), virtual gel, and cluster analysis for validation. The correlation between standard strain S. aureus 25,923 THL (SA-18) and all strains was significant since protein peak of m/z 5305 ± 2 Da was common in all strains, including SA-18. Twenty-six (9.12%) and fifteen (5.26%) out of all samples were found as contaminated by Staphylococci and S. aureus, respectively. The findings suggest that MALDI-TOF MS-based PCA is a promising fast method to categorize S. aureus in dairy foods, in need of continuous monitoring of foodborne pathogens for public health. Eficacia del método EM MALDI-TOF para la detección de Staphylococcus aureus aislados de leche cruda y alimentos lácteos artesanalesEl presente estudio tuvo por objeto caracterizar 27 aislados de Staphylococcus aureus entre un total de 44 estafilococos recuperados de leche cruda y alimentos lácteos artesanales tradicionales (n=285) en Anatolia Central y las regiones mediterráneas de Turquía. Para ello se utilizó el análisis de componentes principales (PCA) filoproteómico, basado en la EM MALDI-TOF. Se analizaron los datos mostrados por los espectros, seguidos por el índice de correlación compuesto (CCI), el gel virtual y el análisis de clúster para su validación. Se constató que la correlación entre la cepa estándar S. aureus 25923 THL (SA-18) y todas las cepas fue significativa, ya que el pico proteico de m/z 5305 ± 2 Da fue común a todas ellas, incluida la SA-18. De todas las muestras analizadas, 26 (9.12%) resultaron contaminadas por estafilococos y 15 (5.26%) por S. aureus. Los resultados dan cuenta de que el PCA basado en la EM MALDI-TOF es un método rápido y prometedor para categorizar S. aureus en los alimentos lácteos que requieren, para garantizar la salud pública, un seguimiento continuo de los patógenos transmitidos por los alimentos.

No abstract

Teh venoms of teh scorpions Androctonus crassicauda and Leuris abdullahbayrami, scorpion species each of teh two members of teh Buthidae family, were analyzed by MALDI–TOFMS in a mass range between 1 and 50 kDa. Interspecies differentiation was evaluated over peptide and protein molecules in dis mass range. Teh similarities and differences between two different scorpion species were revealed wif teh TEMPprincipal component analysis study, which was conducted wif spectral patterns including peptide and protein profiles. Teh similarity rate of teh LAB-123 and teh LAB460 scorpion venoms of teh same species was found as 66% while teh similarity rates of venoms of teh ACR species to teh LAB species ranged from zero to 37%. It was demonstrated dat scorpion venoms belonging to two different species from teh Buthadia family can be differentiated wif teh halp of dendrogram and gel profile, CCI color matrix, 3D or 2D-scattering profile, spectral mass loading data formed by peptide and protein spectral patterns of eleven scorpion venoms. It is anticipated dat dis approach, which was used for teh first time wif teh application of MALDI-TOFMS-based PCA analysis for teh differentiation of scorpion venoms, will be useful in differentiating venoms wif different spectral patterns.

No abstract