Araştırmacılar(17)

• Akkaş, Önder
• Akyüz, Sümeyye
• Aslan, Sumeyye
• Aydin, Merve
• Celebi, Selahattin
• Cülhan, Bariş
• Çikman, Aytekin
• Dabanlioglu, Bulent
• Ertek, Mustafa
• Gökhan Taş, Necip
• Gülhan, Barış
• Gültekin, Esra
• Gümral, R.
• Islamoglu, Fatma
• Kara, Murat
• Terzioglu, Merve Aydin
• Yilmaz, Aysun

• ArticleAçık Erişim2026/r/ebyu/19222
  Diagnostic Performance of the BioFire® Joint Infection Panel in Native Septic Arthritis and Periprosthetic Joint Infection: A Retrospective Diagnostic Accuracy Study

  Gür, Volkan; Akyüz, Sümeyye; Yapici, Furkan; Gülhan, Barış; Doğan, İbrahim; Gökgöz, Mehmet Burak; Ozturk, Akin; Topaluğurlu, Nedim Batuhan; Dündar, Harun

  Objective: Rapid identification of causative microorganisms is essential in suspected native septic arthritis and periprosthetic joint infection. This study evaluated the diagnostic performance of the BioFire® Joint Infection Panel and assessed its agreement with conventional culture and systemic inflammatory biomarkers. Methods: Hospital records from January 2025 to April 2026 were retrospectively reviewed. Of 115 screened patients with suspected joint infection, nine were excluded because BioFire® testing had not been performed and only culture results were available. The final analysis included 106 synovial fluid samples. All samples were tested using conventional culture and the BioFire® Joint Infection Panel during the same clinical episode. Demographic data, infection category, localization, C-reactive protein, erythrocyte sedimentation rate, procalcitonin, and white blood cell count were recorded. Agreement was assessed using Cohen’s kappa, discordance using the McNemar test, and diagnostic performance using culture as the reference method. Results: Sixty-five samples (61.3%) were classified as suspected native septic arthritis and 41 (38.7%) as periprosthetic joint infection. BioFire® was positive in 22 samples (20.8%) and culture was positive in 32 (30.2%). Overall agreement was 86.8%, with substantial agreement according to Cohen’s kappa (0.656). Discordance was significant, predominantly due to culture-positive/BioFire®-negative samples (P = 0.013). BioFire® showed 62.5% sensitivity [95% confidence interval (CI): 43.7-78.9), 97.3% specificity (95% CI: 90.6-99.7), 90.9% positive predictive value, 85.7% negative predictive value, and 86.8% accuracy. C-reactive protein, procalcitonin, and white blood cell counts were significantly higher in patients with suspected native septic arthritis. Conclusion: The BioFire® Joint Infection Panel provides rapid and highly specific microbiological support in suspected joint infection. However, its moderate sensitivity and inability to detect off-panel organisms indicate that it should complement rather than replace conventional culture.

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• ArticleYayıncıda açık erişim2026/r/ebyu/19212
  In vitro evaluation of the antimicrobial, antioxidant, and cytotoxic effects of Zingiber officinale Roscoe ethanolic extract on A2780 ovarian cancer cells

  Gunay, Murat; Akyüz, Sümeyye; Akyüz, Emrullah

  Aim: To evaluate the in vitro antimicrobial, antioxidant, and anticancer activities of the ethanol extract obtained from Zingiber officinale Roscoe rhizomes (ZRE) against the A2780 ovarian cancer cell line. Materials and Methods: Antimicrobial activity was assessed using disk diffusion and broth microdilution methods. Antioxidant capacity was determined by DPPH and ABTS radical scavenging assays. Anticancer effects were investigated via the XTT cell viability assay. Results: The highest antimicrobial activity was observed against Staphylococcus aureus (16,67±0,57 mm, MIC 64 μg/mL) and Candida albicans (18,67±0,57 mm, MIC 64 μg/mL). Strong, concentration-dependent antioxidant activity was detected in both DPPH and ABTS assays. The IC₅₀ values in the A2780 cell line were determined to be 185±12 μg/mL at 24h and 92±8 μg/mL at 48h. Conclusion: ZRE exhibited notable antimicrobial activity, potent antioxidant capacity, and cytotoxic effects. The originality of this study lies in the simultaneous investigation of ZRE’s multifaceted biological activities.

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• ArticleYalnız künye2026/r/ebyu/18986
  Retrospective analysis of multiplex panel tests in the diagnosis of respiratory tract infections

  Ozturk, Ali; Koklu, Ramazan; Aydin, Merve; Celebi, Basar; Altun, Zehra Turkmen; Erdogan, Fatma; Evren, Kubra

  Respiratory tract infections (RTIs) remain a major global health concern, particularly in children. The overlapping clinical manifestations of RTIs highlight the need for rapid and accurate diagnostic methods such as multiplex PCR (mPCR). This retrospective single-center study investigated the epidemiology of respiratory pathogens detected by mPCR, focusing on their distribution, age-related patterns, seasonal variation, and coinfections.Nasopharyngeal swab samples from 328 patients with suspected acute RTIs, collected between January 2022 and December 2023, were analyzed using the BioFire FilmArray Respiratory Panel 2.1. Demographic characteristics, clinical findings, pathogen distribution, seasonal trends, and coinfections were evaluated.At least one respiratory pathogen was detected in 270 of 328 specimens, yielding an overall positivity rate of 82.3%. Viral pathogens predominated; human rhinovirus/enterovirus HRV/HEV (28%), adenovirus (21.8%), respiratory syncytial virus (RSV) (14.2%), and influenza viruses (11.3%) were the most frequently identified agents. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and human metapneumovirus (HMPV) were detected in 6.8% and 5.8% of cases, respectively. The vast majority of specimens (91.5%) were from pediatric patients (0-18 years). Coinfections were identified in 31.8% of positive cases, most commonly involving adenovirus and HRV/HEV. Seasonal analysis demonstrated a marked increase in positivity during winter and spring months, accounting for 74% of all positive cases. Bacterial pathogens were rarely detected.mPCR demonstrated high diagnostic value, with pathogens detected in 82.3% of samples, predominantly viral agents. These findings support the role of mPCR in improving diagnostic accuracy and providing valuable regional epidemiological data. Rapid identification of viral pathogens may also support antimicrobial stewardship by facilitating more informed clinical decision-making; however, antibiotic utilization was not evaluated in the present study.

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• ArticleYayıncıda açık erişim2026/r/ebyu/11080
  Evaluation of the Efficacy of Acarbose on Ovarian Microbiota Profile, Ovary–Gut Axis, and SAP (1–10) Gene Expression in Rats Administered With Candida albicans Exosomes

  Dabanlioglu, Bulent; Celebi, Demet; Celebi, Ozgur; Baser, Sumeyye; Guler, Mustafa Can; Tanyeli, Ayhan; Ari, Betul; Kalayci, Sıla Ektas; Fakirullahoglu, Mesud; Kiliclioglu, Metin

  Candida albicans is a commensal fungus of the vaginal and reproductive tract microbiota, but its overgrowth contributes to mucosal infections and reproductive dysfunctions. The fungus secretes exosomes carrying virulence factors, including secreted aspartyl proteinase (SAP) genes, which are critical for tissue invasion and immune modulation. Acarbose, an α-glucosidase inhibitor, has been shown to suppress C. albicans biofilm formation and hyphal transition. This study is aimed at evaluating the effects of acarbose on the ovarian microbiota, gut–ovary axis, and SAP gene expression profile in a rat model following exposure to C. albicans exosomes. Rats were divided into two groups: the control group received intraperitoneal C. albicans exosomes (8 log10 CFU/mL), whereas the acarbose group received the same exosomes followed by oral acarbose (25 mg/kg/day). Exosomes were characterized by NTA and SEM. Ovarian tissue gene expression (SAP1–10) was analyzed by qRT-PCR. Inflammatory cytokines and tight junction proteins were assessed via ELISA, and microbiota composition was determined using 16S rRNA sequencing. Acarbose significantly reduced IL-8 and TNF-α levels while increasing IL-10, ZO-1, claudin-5, and occludin expression compared with Candida-infected controls (p < 0.05). Gut microbiota diversity and classification success were higher in the acarbose group, indicating microbial balance restoration. Acarbose mitigated C. albicans exosome-induced inflammation and barrier dysfunction while enhancing microbial diversity, suggesting its potential role in modulating the ovarian–gut axis and reducing fungal virulence through SAP gene suppression.

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• ArticleYayıncıda açık erişim2026/r/ebyu/11018
  Evaluation of gossypetin’s effects on gut microbiota profile and TLR4, Myd88, NFKB, and NLRP3 signaling pathways in rats

  Akkas, Onder; Celebi, Demet; Celebi, Ozgur; Baser, Sumeyye; Kalayci, Sıla Ektas; Ari, Betül; Guler, Mustafa Can; Dabanlıoglu, Bulent; Celebi, Selahattin; Kılıclıoglu, Metin

  Gut microbiota plays a crucial role in maintaining host homeostasis by regulating metabolic processes and immune responses. Disruptions in microbial composition are closely associated with inflammatory diseases and are often linked to the activation of key signaling pathways such as Toll-like receptor 4/myeloid differentiation primary response 88/nuclear factor kappa TLR4/MyD88/NF-κB and NLR family pyrin domain-containing 3 (NLRP3) inflammasome. Natural bioactive compounds, particularly flavonoids, have gained attention due to their potential to modulate both gut microbiota and inflammation-related pathways. In this context, the present study aimed to evaluate the effects of gossypetin on gut microbiota composition and its regulatory role on TLR4, MyD88, NF-κB, and NLRP3 signaling pathways in a rat model. Adult female Wistar albino rats were divided into control and gossypetin-treated groups (50 mg/kg, oral gavage/56 days dose). Gut microbiota was analyzed by 16S rRNA sequencing, and protein expression levels were assessed using Western blot. Histopathological, immunohistochemical, and immunofluorescence analyses were also in liver, intestinal, and spleen tissue performed. Gossypetin administration reduced microbial diversity and altered microbiota composition, with increases in Mediterraneibacter spp., Blautia spp., and Lactobacillus spp. Western blot results showed significant decreases in NLRP3 (p ≤ 0.01) and NF-κB (p ≤ 0.05) levels, while TLR4 and MyD88 remained unchanged. Histological analyses revealed mild tissue alterations and increased oxidative stress markers. These results suggest that gossypetin modulates microbiota composition and exerts selective anti-inflammatory effects, highlighting its potential in microbiota-associated inflammatory regulation.

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• ArticleYayıncıda açık erişim2026/r/ebyu/10922
  Alternative therapy against CTX-M broad spectrum β-lactamase resistance gene in Klebsiella pneumoniae infection: bee venom and bee venom-derived nanovesicle fraction

  Celebi, Demet; Celebi, Ozgur; Baser, Sumeyye; Taghizadehghalehjoughi, Ali; Dabanlıoglu, Bulent; Guler, Mustafa Can; Aydın, Elif; Yıldırım, Serkan

  Antibiotic resistance is one of the most important problems threatening global public health by complicating the treatment of infections worldwide. The increase in resistant microorganisms creates a serious economic and social burden on healthcare systems and increasingly limits treatment options. Conscious use of antibiotics, infection control measures and the development of alternative treatment strategies are vital to ensure sustainability in health. Klebsiella pneumoniae is the most common gram-negative bacterium among urinary tract infections. Treatment of infections has become difficult due to the resistance to beta-lactam antibiotics. Bee venom (BV) and nanovesicle fractions isolated from BV are bioactive compounds with antimicrobial and antibiofilm activity. The aim of this study was to determine the antimicrobial and antibiofilm effects of BVand bee venom-derived nanovesicle fractions against the nosocomial infection agent K. pneumoniae, and to evaluate CTX-M PCR band detection under the tested conditions. Minimum inhibitory concentration (MIC), antibiofilm activity, fractional inhibition concentrations (FIC), CTX-M PCR band detection, and viability rates in L929 cells were evaluated for both BVand the bee venom-derived nanovesicle fraction against K. pneumoniae. MIC value of nanovesicle fractions isolated from BVwas determined as 1.95 mg/L. In combination with piperacillin and tazobactam, a synergistic effect was detected with a value of 0.5. Antibiofilm activity was measured with the highest absorbance value of 0.163 and 0.094 for BV nanovesicle fractions. A detectable CTX-M PCR band was observed in the BVgroup at 0.5× MIC, whereas no detectable band was observed at both concentrations by day 4. In the bee venom-derived nanovesicle fraction group, no detectable CTX-M PCR band was observed at 2× MIC and 0.5× MIC under the tested conditions. In contrast, detectable CTX-M PCR bands were observed in the piperacillin-tazobactam group. It was reported that the combination groups decreased the viability rate in L929 cell lines. The bee venom-derived nanovesicle fraction showed antimicrobial, antibiofilm, and PCR-based detection findings under the tested conditions, supporting the need for further investigation in broader in vitro and in vivo models.

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• ArticleYayıncıda açık erişim2026/r/ebyu/10676
  Biotechnological application of Escherichia coli outer membrane vesicles for the delivery of Myristica fragrans phytochemicals in pancreatic cancer therapy

  Celebi, Ozgur; Baser, Sumeyye; Ari, Betul; Celebi, Demet; Dabanlioglu, Bulent; Genc, Sidika; Taghizadehghalehjoughi, Ali

  Bacterial outer membrane vesicles (OMVs) are emerging as natural nanocarriers for cancer therapy due to their ability to deliver bioactive molecules and to penetrate the tumor microenvironment. This study investigated the combined effects of Escherichia coli-derived OMVs and Myristica fragrans extract on pancreatic ductal adenocarcinoma (PDAC) cells. OMVs (50 µg/mL) and M. fragrans extract (IC₅₀: 25 µg/mL) significantly reduced PANC-1 cell viability and increased LDH release after 24 h of treatment (p < 0.01). The combination treatment induced oxidative stress, evidenced by increased total oxidant status and decreased antioxidant capacity. Molecular analysis showed upregulation of PTEN expression, reduced phosphorylated AKT levels, and an increased IL-1β/IL-10 ratio. These changes elevated the Bax/Bcl-2 ratio and activated caspase-3, indicating induction of apoptosis (p < 0.01). Our findings suggest that OMVs can effectively deliver M. fragrans phytochemicals to cancer cells, modulating oxidative balance and triggering apoptosis through the PTEN/AKT signaling pathway. This study provides preclinical evidence that combinations of microbial vesicles and plant extracts may enhance therapeutic efficacy against PDAC.

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• ArticleYayıncıda açık erişim2026/r/ebyu/10595
  Determinate the effects of Arabic gum and Lactobacillus acidophilus on the gut microbiota ALPK1/NFKB/NLRP6 and NLRP2 signaling pathway and virulence gene profile in rats with Campylobacter jejuni exosome application

  Ucar, Mahmut; Celebi, Ozgur; Celebi, Demet; Baser, Sumeyye; Guler, Mustafa Can; Tanyeli, Ayhan; Kiliclioglu, Metin; Dabanlioglu, Bulent; Shahbazova, Masma; Yilmaz, Ahmet

  Campylobacter jejuni (CJ), a major cause of bacterial gastroenteritis, employs exosomes to disseminate virulence factors and disrupt host immune homeostasis. This study investigated the therapeutic potential of Arabic Gum (AZ) and Lactobacillus acidophilus (LA), individually and in combination, against CJ exosome-induced intestinal injury in rats, with emphasis on inflammasome-related signaling and microbiota modulation. Rats received AZ, LA, or both following CJ exosome exposure. Molecular analyses, histopathology, and microbiome sequencing were performed to elucidate mechanistic responses. CJ exosomes activated key virulence pathways and triggered pronounced inflammatory signaling characterized by alpha kinase 1 (ALPK1), Nuclear Factor Kappa B (NF-κB), and NOD-like Receptor Pyrin (NLRP) upregulation, accompanied by epithelial injury and dysbiosis. Treatment with AZ or LA alone attenuated inflammasome activation and partially restored immune and microbial balance. Notably, the combined treatment produced a synergistic effect, effectively suppressing ALPK1/NF-κB/NLRP signaling and reestablishing a more physiologic microbial community structure. These improvements were associated with reductions in pro-inflammatory cytokines and markers of tissue damage, as well as substantial recovery in intestinal, hepatic, and splenic architecture. Overall, AZ and LA significantly mitigated CJ exosome-mediated pathology, with the combined therapy demonstrating superior efficacy. The findings suggest that co-administration of AZ and LA may offer a promising dual-modal strategy to counteract CJ-induced inflammatory and microbial disturbances, potentially supporting future therapeutic approaches targeting exosome-mediated pathogenesis.

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• ArticleAçık Erişim2026/r/ebyu/10369
  Antifungal susceptibility and in vitro virulence characteristics of clinical Magnusiomyces/Saprochaete isolates: a multicenter study from Türkiye

  Ozturk, Ali; Aydin, Merve; Sahin, Elif Ayca; Gulmez, Dolunay; Tanrıverdi, Elif Seren; Otlu, Baris; Arikan-Akdagli, Sevtap; Ibrahim, Bashar; Ozhak, Betil; Ozyurt, Ozlem Koyuncu

  Invasive infections due to Magnusiomyces/Saprochaete species are an emerging problem in immunocompromised patients and are often underrecognized because of misidentification and intrinsic resistance to some antifungals. This multicenter study investigated the species distribution, antifungal susceptibility patterns, and key virulence traits of clinical isolates from Türkiye. A total of 133 clinical isolates collected between 2010 and 2024 from 18 hospitals in 10 cities were identified by MALDI-TOF MS and ITS/LSU sequencing. MICs of amphotericin B, fluconazole, voriconazole, itraconazole, posaconazole, and flucytosine were determined using the EUCAST broth microdilution method. Biofilm formation and esterase, caseinase, secreted aspartyl proteinase, phospholipase, and hemolysin activities were assessed phenotypically. Sequencing identified 107 isolates (80.4%) as Magnusiomyces capitatus and 26 (19.6%) as Magnusiomyces clavatus, MALDI-TOF MS identified 106 (79.7%) as M. capitatus and 27 isolates (20.3%) as M. clavatus. There was 99.2% agreement between MALDI-TOF MS and sequencing results. Voriconazole, amphotericin B, and posaconazole showed the lowest MICs, whereas fluconazole displayed wide MIC ranges and limited activity. Overall, 97.7% of isolates were strong biofilm producers, with significantly higher biofilm production in M. capitatus. In contrast, M. clavatus showed higher caseinase and esterase activity. This study provides the most extensive multicenter dataset on Magnusiomyces/Saprochaete in Türkiye and underscores their considerable pathogenic potential through strong biofilm formation and tissue-degrading enzyme activities. Accurate species-level identification using MALDI-TOF MS supported by molecular methods is essential, and limited fluconazole activity suggests that voriconazole and amphotericin B should be prioritized in species-guided treatment strategies.

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• ArticleYayıncıda açık erişim2026/r/ebyu/10335
  Comparison of clinical outcomes associated with RSV and influenza infections in adults: a multicenter study from Türkiye (for AP-TR)

  Akdemir, İrem; Selçuk Özger, Hasan; Hocagil, Tuğba Akkaya; Kayaaslan, Bircan; Alay, Handan; Top, Özge Özgen; Kazak, Esra; Kalın Ünüvar, Gamze; Erbay, Ayşe; Çınar, Güle

  Objectives Respiratory syncytial virus (RSV) is an increasingly recognized cause of serious respiratory illness in adults, yet data from middle-income countries remain scarce. This study aimed to compare clinical outcomes of RSV and influenza virus infections in hospitalized and outpatient adults in Türkiye. Methods This retrospective multicenter study included 3299 adult patients (≥18 years) with polymerase chain reaction-confirmed RSV (n = 628) or influenza (n = 2671) from 21 centers across Türkiye between January 2022 and March 2024. The primary outcome was viral infection–related hospitalization. The secondary composite outcome was intensive care unit (ICU) admission and/or 30-day mortality among hospitalized patients. Propensity score–based overlap weighting was used to adjust for baseline differences including age, risk group, clinical severity, co-infection status, and study center. Results After overlap weighting, RSV infection was not significantly associated with increased hospitalization risk compared to influenza (odds ratio [OR]: 0.96, 95% confidence interval [CI]: 0.77-1.20, P = 0.705). Similarly, no significant difference was observed in the composite outcome of ICU admission or 30-day mortality (OR: 1.40, 95% CI: 0.95-2.05, P = 0.088). Age ≥60 years, high-risk comorbidities, and severe acute respiratory infection presentation were the primary independent predictors of both hospitalization and worse outcomes. Bacterial or fungal co-infections and secondary infections were observed in 12.9% and 7.3% of hospitalized patients, respectively, with no significant difference between RSV and influenza groups. Conclusion After adjustment for baseline characteristics, RSV and influenza were associated with comparable risks of hospitalization and severe clinical outcomes in adults. Host-related factors, particularly older age and underlying comorbidities, were the dominant determinants of adverse outcomes. These findings from a largely unvaccinated, middle-income country cohort highlight the need to expand RSV and influenza vaccination programs targeting high-risk adult populations.

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