BackgroundA toxin-antitoxin (TA) system is a set of two or more closely linked genes that are encoded as a poison and a corresponding antidote on a protein. In typical bacterial physiology, an antitoxin binds to a toxin and neutralizes it, which prevents the bacterium from killing itself. We aimed to determine whether P.aeruginosa and Staphylococcus isolates have TA genes and to investigate whether there is a relationship between the expression levels of TA genes and resistance to antibiotics.MethodsThis study included 92 P. aeruginosa and 148 Staphylococcus isolates. RelBE, higBA genes were investigated in P.aeruginosa by multiplex polymerase chain reaction (PCR). The mazEF gene and the all TA genes expression were detected by real time PCR.ResultsRelBE and higBA genes were detected in 100% of P. aeruginosa. It was found that the level of relBE TA gene expression is increased in isolates sensitive to aztreonam compared to resistant isolates (p<0.05). The mazEF gene was detected in 89.1% of Staphylococcus isolates. In terms of MazEF gene expression level there was no significant difference between methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA) isolates (p>0.05) whereas there was a significant difference between MSSA and coagulase-negative Staphylococcus (CNS) isolates, MRSA and CNS isolates (p<0.05). The levels of mazEF gene expression were found to be higher in isolates sensitive to gentamicin, ciprofloxacin, levofloxacin, clindamycin, phosphomycine, nitrofurantoin, fusidic acid, cefoxitin compared to resistant isolates (p<0.05).ConclusionStudies on the prevalence and functionality of TA systems emphasize that it may be possible to have new sensitive regions in bacteria by activating TA systems. The results of this study lead to the idea that resistance to antibiotics can be reduced by increasing TA gene expression levels. But there is need for further studies to support and develop this issue.

OBJECTIVE: Toxin-antitoxin genes RelBE and HigBA are known to be involved in the formation of biofilm, which is an important virulence factor for Pseudomonas aeruginosa. The purpose of this study was to determine the presence of toxin-antitoxin genes and exoenzyme S and exotoxin A virulence genes in P. aeruginosa isolates and whether there is a relationship between toxin-antitoxin genes and virulence genes as well as antibiotic resistance. METHODS: Identification of the isolates and antibiotic susceptibilities was determined by a VITEK 2 (bioMérieux, France) automated system. The presence of toxin-antitoxin genes, virulence genes, and transcription levels were detected by real-time polymerase chain reaction. RESULTS: RelBE and HigBA genes were detected in 94.3% (82/87) of P. aeruginosa isolates, and exoenzyme S and exotoxin A genes were detected in all of the isolates (n=87). All of the isolates that harbor the toxin-antitoxin and virulence genes were transcribed. There was a significant increase in the RelBE gene transcription level in imipenem-and meropenem-sensitive isolates and in the HigBA gene transcription level in amikacin-sensitive isolates (p<0.05). There was a significant correlation between RelBE and exoenzyme S (p=0.001). CONCLUSION: The findings suggest that antibiotic resistance may be linked to toxin-antitoxin genes. Furthermore, the relationship between RelBE and exoenzyme S indicates that toxin-antitoxin genes in P. aeruginosa isolates are not only related to antibiotic resistance but also play an influential role in bacterial virulence. Larger collections of comprehensive studies on this subject are required. These studies should contribute significantly to the solution of the antibiotic resistance problem.

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Background/aim: To contribute to case management algorithms and guidelines by evaluating the clinical symptoms, laboratory data, risk factors and mortality rates of patients admitted to health institutions with tick bite in Tokat. Materials and methods: A total of 141 patients has at least two criteria determined by the CCHF study group of the Ministry of Health of the Republic of Turkey were included in the study. The virus determination was made from the blood by conventional PCR. Epidemiological data such as socio-demographic variables (gender, age groups, occupation) and risk factors were compared with clinical symptoms, biochemical and hematological parameters. Results: Of the patients, 83 (58.9%) were male, 84(59.6%) were positive. Five patients (5.95%) died in the PCR-positive group. Fever (p=0.036) (Table 3) and tick contact history (p

Introduction: Breast cancer consists huge amount of the cancerrelated death in population. Ovarian cancer is the second most frequent seen type of gynecological cancer and has the highest mortality among gynecological cancers since most cases are detected late. The current study intended to determine the prevalence of oncogene mutations, especially BRCA1 and BRCA2, in high-risk patients diagnosed with ovarian and breast cancer in the Black Sea region of our country. Material and method: Between August 2017 and January 2022, a total of 223 individuals who applied to our center and met the genetic test criteria were included in the study. Next-generation sequencing (NGS) was used to detect germ-line deleterious variants in genes included in the oncogenetic panel of patients (34 genes). Results: Among the 223 patients analyzed within the scope of the study, 195 had breast cancer, and 28 had ovarian cancer, resulting in the detection of 15 different pathogenic variants of BRCA1 (%4,9) and BRCA2 (%6,7) genes in 26 (11.6%) patients. In the analysis of 32 oncogenes other than BRCA1 and BRCA2 genes, 26 different pathogenic (P) or likely pathogenic (LP) variants were detected in a total of 35 patients (15.7%). Based on the analysis of 223 breast/ ovarian cancer patients together, 41 different pathogenic (P) or likely pathogenic (LP) variants were found in 61 patients (27.3%). Furthermore, 65 different VUSs (Variant of Uncertain Significance) were detected in 73 patients (32.7%). Conclusion: This is the first study to be conducted in our region in a single center located in the Black Sea region. The study was conducted in a single center within the Black Sea region and, to our knowledge, provides the first data in this region in terms of cancer genes other than BRCAs. To appreciate of the genetic susceptibility spectrum of hereditary breast and/or ovarian cancer better, it is imperative to clarify the risks associated with genes other than BRCAs, which carry a high risk for other breast and ovarian cancers, as well as BRCA1 and BRCA2. Therefore, patients in the risk group must undergo multigene panel testing in addition to routine BRCA1 and BRCA2 gene testing. We detected two novel variants in the BRCA2 gene and five novel variants other than BRCA oncogenes. Furthermore, the results of this study contributed to the development of our country's specific variant pool.