This study aimed to evaluate the effectiveness of combinations of colistin (COL) with cinnamaldehyde (CIN) or eugenol (EUG) against planktonic and biofilm forms of colistin-resistant clinical Acinetobacter baumannii isolates. Minimum inhibitory concentration (MIC) values of COL and essential oil components in 10 colistin-resistant clinical isolates were evaluated by the broth microdilution method. Interactions were classified by the fractional inhibitory concentration index (ΣFICI) using the checkerboard method. Biofilm formation was detected using the crystal violet method and the inhibitory effects of selected combination ratios on biofilm formation were evaluated in isolates showing synergy. In addition, the time-dependent effects of synergy combinations on 48-h pre-formed biofilm biomass were examined. Median MIC values of COL, CIN, and EUG were 8 (4–32), 128 (128–128), and 512 (256–1024) µg/mL, respectively. In combination, the MIC of COL decreased to 1 (0.5–16) µg/mL with CIN and to 2 (0.5-8) µg/mL with EUG (p = 0.002). Synergy was observed in half of the isolates in both combinations (median ΣFICI: 0.532 and 0.469). Three isolates formed strong biofilms and seven formed moderate biofilms. Biofilm inhibition ranged from 1.1

OBJECTIVES:Streptococcus pneumoniae acquiring multidrug resistance globally, which poses a threat to the effective treatment of respiratory infections. This systematic review and meta-analysis aimed to evaluate global and regional antimicrobial susceptibility patterns of S. pneumoniae respiratory isolates collected between 2015 and 2024. METHODS:Scopus, PubMed and Web of Science were searched from January 2015 to December 2024 following PRISMA guidelines. Inclusion criteria comprised English-language original studies reporting antibiotic susceptibility rates of S. pneumoniae isolated from respiratory samples of human origin, while studies with fewer than 10 isolates or lacking clear specification of sample type were excluded. Participants were respiratory samples yielding S. pneumoniae from human subjects across six WHO-defined regions. No interventions were applied, as this was an observational synthesis of surveillance and observational studies. Study quality was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Prevalence Studies. A random-effects model with double arcsine transformation was applied to pool susceptibility proportions, and subgroup analyses were conducted by geographical region. RESULTS:Thirty-three studies comprising 20,768 isolates were included. Overall susceptibility rates were highest for linezolid (100%) and vancomycin (99%). Penicillin susceptibility was 77% (95% CI: 65-88), but markedly lower in the African (61%) and Eastern Mediterranean (26%) regions. Erythromycin (35%) and tetracycline (42%) susceptibility showed significant declines in the Western Pacific region (3% and 11%, respectively). Trimethoprim-sulfamethoxazole (48%) and clindamycin (60%) also displayed regional variability. Sensitivity analyses restricted to low-risk studies confirmed the robustness of findings. CONCLUSIONS:Antimicrobial susceptibility of S. pneumoniae respiratory isolates varies substantially by region. These results support the importance of regional antibiotic stewardship strategies and updated treatment guidelines to address declining susceptibility and emerging resistance patterns.

Objectives:This study aimed to evaluate the diagnostic performance of the combination disk method and carbapenem inactivation method (CIM) for detecting carbapenemase production in Enterobacterales isolates with reduced susceptibility or resistance to carbapenems, using real-time multiplex polymerase chain reaction (PCR) as the reference method. Materials and Methods:Enterobacterales isolates obtained from clinical samples between 2015 and 2016, which were at least minimally susceptible or resistant to at least one carbapenem, were included in the study. Phenotypic evaluation was performed using the KPC&MBL&OXA-48 combination disk kit (Liofilchem, Italy), which detects Klebsiella pneumoniae carbapenemase (KPC), metallo-β-lactamase (MBL), and OXA-48-type carbapenemases. In addition, the CIM method was applied. For genotypic confirmation, the KPC, OXA-48, and New Delhi metallo-β-lactamase (NDM) genes were investigated using the BD MAXTM CRE Assay (Becton, Dickinson and Company, Sparks, MD, USA). Diagnostic accuracy parameters and the agreement coefficient (κ) were calculated for the index tests. Results:A total of 111 Enterobacterales isolates were analyzed. The majority of isolates were K. pneumoniae (n=80; 72.1%) and Escherichia coli (n=20; 18.0%). Carbapenemase genes were detected in 90 isolates by real-time multiplex PCR. The OXA-48 gene predominated (68.5%), while OXA-48+NDM (9.9%) and NDM (2.7%) were also detected; KPC was not detected. The sensitivity and specificity of the temocillin resistance-based phenotypic approach for predicting the presence of OXA-48 or OXA-48+NDM were 100.0% and 95.8%, respectively (κ=0.97). The MBL phenotype of isolates carrying NDM showed complete agreement with multiplex PCR for carbapenemase detection using the CIM test (sensitivity and specificity 100%, κ=1.00). Conclusion:The carbapenem inactivation method demonstrated high diagnostic accuracy for detecting carbapenemase production. The combination disk method, including temocillin resistance and ethylenediaminetetraacetic acid (EDTA)-based evaluation, showed strong performance in predicting OXA-48- and NDM-associated carbapenemases. However, in endemic regions, phenotypic results should ideally be confirmed by molecular methods.

AIMS:A synthesis of four silver(I) complexes was conducted, and they were evaluated for their antimicrobial properties and their ability to inhibit the formation of biofilms. Additionally, their binding affinities to DNA and BSA were investigated. MATERIALS & METHODS:The complexes, chloro[1-isopropyl-3-(3-methylbenzyl)-5,6-dimethylbenzimidazole-2-ylidene]silver(I) (2a), chloro[1-isopropyl-3-(3-chlorobenzyl)-5,6-dimethylbenzimidazole-2-ylidene]silver(I) (2b), chloro[1-methallyl-3-(3-methybenzyl)-5,6-dimethylbenzimidazole-2-ylidene]silver(I) (2c) and chloro[1-methallyl-3-(3-chlorobenzyl)-5,6-dimethylbenzimidazole-2-ylidene]silver(I) (2d) were prepared in 82-84% yields and fully characterized. The biological properties of both ligands and complexes were evaluated in vitro against S.aureus, E.faecalis, E.coli, A.baumannii, C.albicans, DNA and BSA. RESULTS AND CONCLUSIONS:The complexes 2a-d exhibited a significant inhibitory effect on diverse bacterial biofilms, with percentages ranging from 73.6% to 80.3% for S.aureus, 69.5% to 85.9% for E.faecalis, 76.9% to 88.6% for E.coli, 75.9% to 84.6% for A.baumannii and 70.1% to 82.3% for C.albicans. The most significant activities were observed with complex 2b at 8.5 µM. It was observed that silver(I) complexes exhibited more effective binding to DNA (4.92 × 103 for 2a), while NHC precursors displayed a higher binding affinity for BSA (5.52 × 104 with 1-isopropyl-3-(3-methylbenzyl)-5,6-dimethylbenzimidazole chloride). While the precursors of ligands exhibited significant toxicity at their highest MIC concentrations, the complexes demonstrated minimal toxicity.

AIMS:Metal-N-heterocyclic carben (NHC) complexes have garnered significant attention from synthesis chemistry. Silver is well known for its broad-spectrum antimicrobial activity, and it exhibits their activities with different mechanisms. In this study, we combined these two important scaffolds, analyzed for possible antimicrobial and antibiofilm activity, and evaluated the interactions against DNA Gyrase, SarA, Human Serum Albumin, and DNA for getting insight into the antimicrobial and antibiofilm details. MATERIALS & METHODS:Four new Ag-NHC complexes (2a-d) were prepared from corresponding benzimidazolium salts (1a-d) and revealed by elemental analysis, FT-IR, NMR, LC-MS, and HRMS. The antimicrobial and antibiofilm properties of both ligands and complexes were evaluated with in-vitro and molecular docking methods which were performed against DNA Gyrase, SarA, Human Serum Albumin, and DNA. RESULTS AND CONCLUSIONS:1d showed superior activity while 2a and 2d were effective against C. albicans, with activity comparable to fluconazole in the range of 8.6-8.7 µM. The highest binding affinity was recorded for 2a as -7.93 kcal/mol against DNA Gyrase, while 2b has the best interactions with -5.49 kcal/mol against SarA. and -7.74 kcal/mol binding affinity was determined for 2a with molecular docking. All the molecules interacted with the same grove of DNA.

Introduction: The "ESKAPE" group of bacteria is a group of pathogens that poses aglobal health threat due to their ability to escape the biocidal effects of antibiotics. This group includes Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. This study aimed to determine the biofilm-forming activities of ESKAPE group bacteria from different clinical specimens using two different methodologies and to compare the results of these two approaches. Materials and Methods: In cultures obtained from various clinical specimens collected from patients in Sivas Cumhuriyet University Faculty of Medicine Practice and Research Hospital services and intensive care units, 27 isolates of E. faecium, S. aureus, K. pneumoniae, A. baumannii, P. aeruginosa, and 26 isolates of Enterobacter spp. were identified. The biofilm production capacities of these microorganisms were assessed using the Congo red agar method and the microtiter plate assay. Statistical analyses were conducted using the McNemar test and Cohen's kappa test. Results: No concordance was observed between the methods in S. aureus, A. baumannii, and P. aeruginosa isolates. In A. baumannii and P. aeruginosa isolates, the microtiter plate assay appears to be more sensitive than other methods. Using this method, biofilm formation was detected at a higher frequency. For E. faecium and K. pneumoniae, a moderate level of concordance was observed between the methods, whereas for Enterobacter spp., both methods demonstrated perfect agreement. The p-values determined for S. aureus, E. faecium, A. baumannii, P. aeruginosa, K. pneumoniae, and Enterobacter spp. were found to be 0.023, 0.025, <0.001, <0.001, and 0.366, respectively. The corresponding kappa values were calculated as-0.068, 0.501, 0, 0.13, 0.375, and 1. Conclusion: Since different methods used for biofilm detection may yield varying results, it is of paramount importance to select the most appropriate research method. This study demonstrated the consistency of the methods in biofilm research. It showed that the microtiter plate method provides more consistent results, especially in biofilm detection in non-fermenting bacteria such as P. aeruginosa and A. baumannii.

Objective: Hepatitis B virus (HBV) infections cause a major public health problem worldwide diagnosis and treatment of HBV infection is an important issue. Detection of HBV DNA by polymerase chain reaction (PCR) and demonstration of viral replication together with serologic and biochemical indicators are very useful in diagnosis and treatment. In this study, we aimed to evaluate the relationship between HBsAg serum concentration values and other serologic parameters related to HBV in the diagnosis of hepatitis B. Methods: HBsAg, HBV DNA, Anti HBc IgG, Anti HBc IgM, HBeAg, and Anti HBe values obtained from blood sera taken from patients in Sivas Cumhuriyet University Application and Research Hospital Microbiology Laboratory between 2012-2020 were retrospectively analyzed from laboratory records. Results: A positive correlation was found between HBsAg serum titers and HBV DNA and between HBeAg and HBV DNA. It was found that HBV DNA positivity rates increased as HBsAg titers increased. Similarly, it was found that HBc IgG positivity increased as HBsAg titers increased. HBeAg positivity increased with increasing HBsAg titers up to a certain point, while HBeAg positivity decreased after a certain titer. When HBV DNA results were compared with HBeAg results, the relationship between the two values was found to be significant. Conclusion: We think that it is useful to investigate the relationship between serum concentrations of HBsAg and HBV DNA and other serologic parameters in the accurate identification of HBV infection and monitoring of treatment.

Using existing adrentimicrobials with essential oil components to prevent antimicrobial resistance is an alternative strategy. This study aimed to evaluate the resistance status, synergistic combinations, and in vitro biofilm formation activities of clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA), Stenotrophomonas maltophilia and Candida albicans against antimicrobial agents and cinnamaldehyde, carvacrol, eugenol, limonene and eucalyptol. Antimicrobial activities were evaluated by microdilution, cytotoxicity by XTT, synergy by checkerboard and time-kill, and biofilm inhibition by microplate methods. Cinnamaldehyde and carvacrol showed strong antimicrobial activity. Synergistic effects were observed when using all essential oils with antimicrobials. Only two C. albicans isolates showed antagonism with cinnamaldehyde and fluconazole. The constituents showed cytotoxic effects in the L929 cell line (except limonene). A time-kill analysis revealed a bacteriostatic effect on S. maltophilia and MRSA isolates and a fungicidal effect on C. albicans isolates. These results are important for further research to improve antimicrobial efficacy or to develop new agents.

One of the mechanisms responsible for antibiotic resistance in Klebsiella pneumoniae is the enzymes produced by the bacteria; another important mechanism is the ability to form biofilm. In this study, antibiotic resistance, genes associated with virulence, and biofilm-forming properties of K. pneumoniae strains were investigated. A total of 100 K. pneumoniae isolates were obtained from different clinical samples identified by Matrix-Assisted Laser Desorption/Ionization time-of-flight Mass Spectrometry. Antimicrobial susceptibility testing was performed with the Phoenix 100 apparatus. The biofilm forming properties of strains were determined by the microtiter plate method. For molecular analysis, genes encoding the carbapenemase enzyme (bla(OXA-48), bla(NDM-1), bla(IMP), and bla(VIM)) and biofilm-related genes (treC, luxS, mrkA, and wza) were investigated by polymerase chain reaction (PCR). While 76% of clinical isolates were resistant to three or more antimicrobials, 24% were classified as non-multidrug resistant (non-MDR). When biofilm-forming capacities of clinical isolates were tested, it was determined that the resistant-isolates produced 59.2% strong biofilm, and susceptible-isolates produced 12.5% strong biofilm. According to PCR results, carbapenemase genes were determined as follows: bla(OXA-48)-70%, bla(NDM)-49%, and bla(KPC)-19%, bla(OXA-48)/bla(NDM)/bla(KPC)-12%, bla(OXA-48)/bla(NDM)-26%, and bla(OXA-48)/bla(KPC)-4%. The biofilm-associated genes in bacterial isolates were determined as follows: luxS-98%, treC-94%, mrkA-88%, and wza-15%. In addition, Hierarchical Clustering Tree and Heatmap analysis revealed an association between isolates that lacks resistance genes and isolates lacks biofilm-formation related genes that were included in MDR or non-MDR classes. As a result, biofilm should be considered in the treatment of MDR infections, and therapy should be planned accordingly. In addition, pursuing the data and genes of antibiotic resistance is significant for combating resistance.

In recent years, resistance to antimicrobials has become a global problem. Despite the need for new antibiotics with the increase of resistant bacteria, developing new antimicrobials is problematic. Biofilms formed by microorganisms play an essential role in the development of resistance. We aimed to investigate the antimicrobial and antibiofilm activities of N-heterocyclic carbene (NHC) complexes. In this study, previously synthesized and characterized NHC complexes on standard bacterial and fungal strains were investigated. The minimal inhibition concentration (MIC) test was used to determine the antimicrobial activities of the compounds, and the biofilm inhibition concentration test was used to determine the anti-biofilm activities. Compounds 2b and 2c showed potent antimicrobial activity on microorganisms between <=1.9 and 7.8µg/mL. Antimicrobial activity in salts of compounds (1a-1c) was weaker than silver compounds (2a-2c). The antibiofilm activity was between 27 and 79%, especially in silver-bound compounds (2a-2c). Benzimidazole derivative NHC compounds that we evaluated in our study were found to have significant antimicrobial and antibiofilm effects on pathogenic microorganisms. These compounds, which we assessed in our study, may be antimicrobial drug candidates that can be used in different areas. It will be essential to conduct further in vitro and in vivo studies on this subject.

Mushrooms, which have been collected to meet the nutritional needs of the world for many years, have gained medical importance thanks to the bioactive compounds they produce. Thanks to studies carried out to determine mushroom diversity, the number of species identified is increasing year by year. Accordingly, in recent years, studies conducted to determine the biological activities of metabolites produced by fungi have been increasing. The present study was conducted to determine the cytotoxic, antioxidant, antibiofilm and antimicrobial activities of the seven different mushroom species (Craterellus cornucopioides, Hymenopellis radicata, Lepista nuda, Pisolithus arhizus, Ramaria flava, Schizophyllum commune, and Tricholoma ustale) collected from Tokat and Yozgat regions located in northern and central Turkey. Laboratory studies have demonstrated that mushrooms used in this study have different degrees of antibiofilm, antimicrobial, antioxidant and cytotoxic activities. At the end of the study, it is determined that C. cornucopioides and L. nuda species have the highest antimicrobial activity. In addition, mushroom species have biofilm inhibitory effects on indicator microorganisms at varying degrees ranging between 20.7 and 96.3%. As a result of antioxidant activity studies, it was determined that T. ustale has the highest free radical scavenging effect and P. arhizus, which has the highest polyphenol content, has the highest reducing power. Finally, it is determined that, among the mushrooms used in the present study, H. radicata showed higher selectivity on the MDA-MB-231 breast cancer cell line than on the normal cell line tested, while C. cornucopioides showed higher selectivity on the MCF-7 breast cancer cell line.

Five silver(I) complexes, namely chloro[1-methallyl-3-benzyl)benzimidazol-2-ylidene] silver (6), chloro[1-methallyl-3-(2,3,5,6-tetramethylbenzyl)benzimidazol-2-ylidene]silver (7), chloro[1-methallyl-3-(3,4,5-trimethoxylbenzyl)benzimidazol-2-ylidene]silver (8), chloro[1-methallyl- 3-(naphthylmethyl)benzimidazol-2-ylidene]silver (9), and chloro [1-methallyl-3-(anthracen-9-yl- methyl)benzimidazol-2-ylidene]silver (10), were prepared starting from their corresponding benzimidazolium salts and silver oxide in 71–81% yields. A single-crystal X-ray structure of 7 was determined. These five Ag-NHC complexes were evaluated for their antimicrobial and biofilm formation inhibition properties. Complex 10 exhibited high antimicrobial activities comparable to those obtained with standard drugs such as Fluconazole in contact with Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Acinetobacter baumannii, and Candida albicans. The latter complex has been shown to be very efficient in antibiofilm activity, with 92.9% biofilm inhibition at 1.9 μg/mL on Escherichia coli. Additionally, the molecules were optimized with DFT-based computational methods for obtaining insight into the structure/reactivity relations through the relative energies of the frontier orbitals. The optimized molecules were also analyzed by molecular docking method against DNA gyrase of Escherichia coli and CYP51 from Candida albicans.

Human papillomavirus (HPV) is a non-enveloped, commonly sexually transmitted virus with icosahedral symmetry and double-stranded circular DNA. Its genome, which is about 8 kb in size, encodes early genes (E1-8) and two late structural capsid genes (L1 and L2). Among the genes that play a role in viral pathogenesis, L1, E6, and E7 genes frequently exist. The E6 and E7 viral genes have a significant role in apoptosis inhibition, viral spread, development of squamous intraepithelial lesion (SIL), cell immortalization, neoplastic transformation, and invasive cancer. Demonstration of the relationship between cervical cancer and HPV infections has led to increased interest in this subject and the classification of some HPV genotypes in the high-risk group (HR-HPV) for cervical cancer. Numerous commercial molecular tests have been developed for the identification of HPV genotypes involving different approaches. HPV molecular tests approved by the US Food and Drug Administration (FDA) include Hybrid Capture® 2 (HC2), Cervista™, cobas®, Aptima®, and BD Onclarity™. This article reviews the methodologies, limitations, and commonalities of five FDA-approved tests. The HC2 and Cervista™ tests use non-PCR-based signal amplification methods, while the cobas® and BD Onclarity™ tests use PCR-based target amplification methods. On the other hand, the Aptima® test uses the mRNA transcriptional mediated amplification (TMA) method. Each of these methods used in the diagnosis and follow-up of HPV has its strengths and weaknesses. These HPV molecular tests have high sensitivity and specificity. They are also more automated and repeatable than cytological methods. In addition to these advantages, there are also several limitations. Because of these limitations, molecular tests are no more perfect than cytological tests. This situation shows that these tests should not be used alone in the evaluation of HPV infections and cancer identification. On the contrary, HPV test results should be correlated with cytology or biopsy findings.

Objective: Helicobacter pylori (H. pylori) is a Gram-negative microaerophilic bacterium that is associated with diseases such as peptic ulcer, chronic gastritis, gastric MALT lymphoma, and gastric cancer. H. pylori infection is more common in developing countries. The high socioeconomic conditions and elimination of bacterial carriage by antimicrobial treatment reduce the prevalence of H. pylori in developed countries. The fecal H. pylori antigen test has been widely used recently. This test with high sensitivity and specificity constitutes a significant diagnostic method alternative due to its cost-effectiveness and rapid results. In this study, we retrospectively analyzed the presence of H. pylori antigen in the stool samples of patients with gastroduodenal complaints from laboratory records. Methods: Test results of patients who underwent H. pylori antigen rapid cassette test from fresh fecal samples between January 2018 and May 2022 in the Medical Microbiology Laboratory were included in the study. Fresh fecal samples from patients were analyzed using H. pylori Antigen Rapid Test Cassette (Acro Biotech Inc, USA) kits. The statistical analysis of the research was made with IBM-SPSS 25.0 (IBM Co., USA). The chi-square test was used to evaluate the research data. P<0.05 value was considered statistically significant. Results: A total of 5,718 patients, 3,285 (57.5%) women with gastroduodenal complaints, were included in the study. Fecal H. pylori antigen test positivity was determined in 1,429 (25%) of these patients. The antigen positivity rate was found to be higher in women (26.6%) compared to men (22.9%) (p<0.05). In addition, this rate was higher in adult patients (27.4%) than in pediatric patients (10.1%). In addition, this rate was higher in adult patients (27.4%) compared with pediatric patients (10.1%) (p<0.01). Conclusion: The regional prevalence data are informative about the development levels of countries in socioeconomic issues such as urbanization, infrastructure services, and access to clean water. In addition, these data may provide insight into the future prevalence of H. pylori-related diseases. We think that this study, in which the data of our region is shared, contributes to the literature.

Purpose: To investigate the antimicrobial, antibiofilm, and cytotoxicity properties of methallyl substituted benzimidazolium-based, silver-bound N-heterocyclic carbene (Ag(I)-NHC) complexes, with respect to their potential to act as antimicrobial agents.Methods: The antimicrobial, antibiofilm, and cytotoxicity properties of the four complexes, the synthesis and characterization of which were carried out previously, were investigated. The antimicrobial properties were tested using the broth microdilution method, while their antibiofilm potential were determined by microtiter plate assay. The L-929 cell line was used for cytotoxic studies.Results: Strong antibiofilm and antimicrobial effects were produced by Ag(I)-NHC complexes. Compounds 2 and 3 showed potent activities against E. coli strain, with effects similar to that of positive control antibiotic, while compounds 1 and 4 exhibited antimicrobial activity at a concentration of 31.2 μg/mL. The compounds were effective against biofilms formed at concentrations in the range of 32 – 84 %, and degraded mature biofilms at a concentration range of 14 - 66 %. Compounds 1 and 2 did not significantly affect cell survival (p > 0.05), while compounds 3 and 4 significantly reduced cell survival, when compared with untreated cells in the control group (p < 0.001).Conclusion: This study may be one of the few studies on benzimidazolium-derived NHCs. The compounds which produced antimicrobial, antibiofilm, and cytotoxic properties in this study may be valuable and novel antimicrobial agents. Therefore, there is need for further in vivo and in vitro studies on these compounds.

Today, the number of antimicrobials used in treatment has decreased, especially due to drug resistance. We need new antimicrobials. Biofilms are an important cause of antimicrobial resistance. In this study, the antimicrobial and antibiofilm properties of the salt and silver complex of benzimidazolium-based NHC compound, which were previously synthesized and characterized, were evaluated. The antimicrobial properties were tested using the broth microdilution method, while their antibiofilm potential was determined by microtiter plate assay. Salt of the NHC compound (1a) showed antimicrobial activity on microorganisms at concentrations between 31.25-125 µg/mL. The silver complex (2a) of the NHC compound showed higher antimicrobial and antibiofilm activity than the salt compound. This activity was highest on Candida albicans yeast (MIC 3.9 µg/mL). Compound 2a reduced the biofilm structure of C. albicans yeast by 86.1% compared to the control. In addition, compound 2a showed 76.4-80.6% antibiofilm activity on gram-negative bacteria. NHC compounds are seen as a promising resource for the development of new generation antimicrobials. The NHC compound evaluated in this study was found to have significant antimicrobial and antibiofilm activity. These compounds could be an important resource for the discovery of future biofilm-acting antimicrobials.

Kan dolaşım enfeksiyonları (KDE) yüksek mortalite ve morbidite ile seyreden en önemli nozokomiyal enfeksiyonlardandır. Gram negatif bakteriler içerisinde en sık KDE etkeni olan bakterilerden ikisi Escherichia coli ve Klebsiella pneumoniae’dır. Antimikrobiyal direnç bu bakterilerin neden olduğu enfeksiyonların tedavisinin önündeki en büyük sorunlardan birisidir. Direnç sürecinin izlenmesi ve seyrinin belirlenmesi, ampirik tedaviye yön vermesi açısından önemlidir. Bu çalışmada kan dolaşımı örneklerinden izole edilen K. pneumoniae ve E. coli bakterilerinin direnç durumları değerlendirilerek, hastanemizdeki güncel verilerin ortaya konulması amaçlanmıştır. Çalışmada 2016-2021 yılları içerisinde kan örneklerinden izole edilen E. coli ve K. pneumoniae bakterilerinin antibiyotiklere karşı direnç durumları, laboratuvar bilgi sistemi verilerinden alınarak geriye dönük olarak incelenmiştir. Çalışmada 963 kan kültüründen 659 E. coli ve 304 K. pneumoniae izole edilmiştir. Bu bakterilerin %34’ü yoğun bakımlardan, %66’sı diğer kliniklerde yatan hastalardan izole edilmiştir. Tüm antibiyotikler değerlendirildiğinde, yoğun bakımlarda yatan hastalarda direnç oranlarının daha yüksek olduğu görülmüştür. En etkili antibiyotik amikasin olarak bulunmuştur. Yoğun bakım ünitesi izolatlarında Genişlemiş spektrumlu beta laktamaz (GSBL) pozitifliği %51 olarak bulunurken, diğer kliniklerde bu oran %36 olarak tespit edilmiştir. GSBL pozitif izolatlarda direnç oranlarının anlamlı oranda yüksek olduğu görülmüştür. K. pneumoniae izolatlarında amikasin ve meropenem sonuçlarında pandemi öncesi ve pandemi dönemi arasında anlamlı bir fark görülmüştür. Ülkemizdeki sağlık merkezlerinin kendi antibiyotik kullanım politikalarını bilimsel çalışma verilerini dikkate alarak belirlemeleri yararlı olacaktır. Bu nedenle bu çalışma sonuçlarının E. coli ve K. pneumoniae kaynaklı sepsiste uygulanacak olan ampirik tedavi modellerini belirlemede yol gösterici olabileceğini düşünüyoruz.

Abstract Rosemary officinalis L., Pelargonium graveolens L., and Mentha piperita L., essential oils are used by complementary medicine specialists simultaneously with traditional antibiotics for treatment purposes. The chemical composition of essential oils was analyzed by the gas chromatography-mass spectrometry method. In vitro antibacterial and antibiofilm activities of the essential oils were tested against extreme drug-resistant (XDR) colistin-resistant and colistin susceptible Acinetobacter baumannii clinical strains. The synergistic activities between essential oils and colistin antibiotics were investigated by the checkerboard method. The highest antibacterial effect was detected in mint essential oil (2.5–5 μl/ml), followed by pelargonium essential oil (5–20 μl/ml) and rosemary essential oil (5–20 μl/ml). The combination of rosemary essential oil or pelargonium essential oil with colistin showed strong synergistic activity in most of the bacterial strains tested (fractional inhibitory concentration index ≤ 0.5; synergy). As a result of the combination of mint essential oil and colistin, an indifferent effect was observed in only two bacterial strains, and other strains could not be evaluated. No antagonistic effects were observed in any of the tested essential oils. As a result of the effectiveness of the combination, the minimum inhibitory concentration (MIC) values of colistin in XDR-A. baumannii clinical isolates decreased 2–32 fold. Additionally, the sub-MIC concentration of essential oils exhibited an inhibitory effect (48–90%) against the biofilm layer of tested A. baumannii strains.

Candida species are commonly encountered strains associated with a wide range of infections. Unlike bacterial pathogens, fungal pathogens treatment is difficult and the development of resistance has been increasing at an alarming rate. In this study, the antifungal and antibiofilm effect of thyme oil, rosemary oil, mint oil, citronella oil, was tested on Candida albicans, Candida tropicalis, Candida kefyr, Candida glabrata, Candida parapsilosis isolated from clinical samples. The agar disc diffusion method was employed to determine the antifungal effect of the essential oils, and the inhibition of biofilm formation was assessed using microtiter biofilm inhibition assay. The results indicated that all the essential oils inhibited Candida strains and their biofilm in varying degrees. The highest antifungal activity in all isolates was observed in the thyme oil (>50mm), while rosemary oil showed the highest antibiofilm effect (>77%) in all tested strains. These findings led us to assume that the active components found in essential oils might be potential antifungal agents, adding to the repertoire of therapeutic options for the treatment of candidiasis.

Benzimidazole type N‐heterocyclic carbene molecules and their metal complexes have well‐known biological activity. Elemental silver and silver complexes also have antibacterial and antifungal activity. In this study, silver complexes with 1‐allyl 5,6‐dimethylbenzimidazolium derivative ligands were analyzed for their antimicrobial and antibiofilm activities. Additionally, bovine serum albumin (BSA) binding properties of the molecules were analyzed by spectrophotometric methods, and the details of interactions of the molecules with BSA were investigated by molecular docking methods. While N‐heterocyclic carbene salts showed moderate antifungal and antibiofilm activity, silver complexes of these salts have strong antimicrobial activity with <1.9–15.6 μg/ml minimal inhibitory concentration (MIC) values. On the other hand, carbene salts have better affinity against BSA than the complexes. Additionally, the interaction of the optimized complexes with SarA and BSA were analyzed by molecular docking methods. According to in vitro and in silico evaluation, the studied Ag complexes may be utilized for advanced studies.