Researcher: Can, Füsun
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Can, Füsun
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Publication Metadata only Discrepancy between IDSA and ESGBOR in Lyme disease: individual participant meta-analysis in Türkiye(Wiley, 2024) N/A; Yıldız, Abdullah Burak; Çetin, Ecesu; Pınarlık, Fatihan; Keske, Şiran; Can, Füsun; Ergönül, Önder; Koç University İşbank Center for Infectious Diseases (KU-IS CID); School of Medicine; Graduate School of Health SciencesBackground: The evidence on the prevalence of Lyme borreliosis (LB) is limited, but there is a suspicion of overdiagnosis of LB in recent years. We reviewed the LB diagnosis and treatment-related data in Turkiye, based on the Infectious Diseases Society of America (IDSA) 2020 and European Society of Clinical Microbiology and Infectious Diseases Study Group for Lyme Borreliosis (ESGBOR) 2018 guidelines. By detecting the disagreements between these two, we outlined the areas to be improved for future guidelines. Methods: We performed a literature search according to the PRISMA guidelines in PubMed, Ovid-Medline, Web of Science, Turkish Medline, Scopus, CINAHL, ULAKBIM TR Index, Google Scholar and Cochrane Library databases. We included the published cases in a database and evaluated according to IDSA and ESGBOR guidelines. We outlined the reasons for misdiagnoses and inappropriate uses of antibiotics. Results: We included 42 relevant studies with 84 LB cases reported from Turkiye between 1990 and December 2022. Among 84 cases, the most common clinical findings were nervous system findings (n = 37, 44.0%), erythema migrans (n = 29, 34.5%) and ophthalmologic findings (n = 15, 17.9%). The IDSA 2020 and ESGBOR 2018 guidelines agreed on the diagnosis of 71 (84.5%) cases; there was an agreement that 31 cases (36.9%) were misdiagnosed and 40 cases (47.6%) were correctly diagnosed, and there was disagreement for 13 cases (15.5%). Serum immunoglobulin M (IgM), IgG measurements by ELISA and western blot were widely performed, and they were effective in definitive diagnosis merely when used according to guidelines. Inappropriate use of antibiotics was detected in 42 (50.0%) of cases which were classified in the following categories: incorrect LB diagnosis, inappropriate choice of antibiotic, inappropriate route of drug administration and prolonged antibiotic treatment. Conclusion: Overdiagnosis and non-adherence to guidelines is a common problem. The discordance between seroprevalence and clinical studies necessitates a consensus over the best clinical approach.Publication Metadata only Neutralizing antibody levels and cellular immune response against Omicron variant in pregnant women vaccinated with mRNA and inactivated SARS-CoV-2 vaccines(Wiley, 2023) Demirci, O.; Ayaz, R.; N/A; Kalafat, Erkan; Talay, Zeynep Gülce; Can, Füsun; Çelik, Ebru; Koç University İşbank Center for Infectious Diseases (KU-IS CID); Graduate School of Health Sciences; School of MedicinePublication Metadata only Selective antibacterial and antibiofilm activity of chlorinated hemicyanine against gram-positive bacteria(Elsevier B.V., 2024) Onbasli, Kubra; Department of Chemistry; Department of Physics; Department of Electrical and Electronics Engineering; Ataç, Nazlı; Gündüz, Hande; Koç, İrem; Khan, Minahil; Savani, Samira; Can, Füsun; Acar, Havva Funda Yağcı; Kölemen, Safacan; Koç University İşbank Center for Infectious Diseases (KU-IS CID); n2STAR-Koç University Nanofabrication and Nanocharacterization Center for Scientific and Technological Advanced Research; School of Medicine; College of Sciences; Graduate School of Sciences and Engineering; College of EngineeringAntibiotic-free therapies are highly needed due to the limited success of conventional approaches especially against biofilm related infections. In this direction, antimicrobial phototherapy, either in the form of antimicrobial photothermal therapy (aPTT) or antimicrobial photodynamic therapy (aPDT), have appeared to be highly promising candidates in recent years. These are local and promising approaches for antibiotic resistant bacterial infections and biofilms. Organic small photosensitizers (PSs) are extensively preferred in antimicrobial phototherapy applications as they offer a great opportunity to combine therapeutic action (aPTT, aPDT or both) with fluorescence imaging on a single molecule. In this study, the bactericidal effect of cationic chlorinated hemicyanine (Cl-Hem)-based type I PS, which can function as a dual aPDT/aPTT agent, was investigated on both planktonic cells and biofilms of different gram-positive (E. faecalis and S. epidermidis) and gram-negative bacteria (P. aeruginosa and K. pneumoniae) with and without 640 nm laser irradiation. Cl-Hem was shown to induce a selective phototheranostic activity against gram-positive bacteria (E. faecalis and S. epidermidis). Cl-Hem exhibited both dose and laser irradiation time dependent bactericidal effect on planktonic and biofilms of S. epidermidis. These results clearly showed that highly potent Cl-Hem can treat resistant microbial infections, while allowing fluorescence detection at the same time. High biofilm reduction observed with combined aPDT/aPTT action of Cl-Hem together with its non-cytotoxic nature points out that Cl-Hem is a promising PS for antibacterial and antibiofilm treatments. © 2024 Elsevier B.V.Publication Metadata only Resensitization to colistin results in rapid and stable recovery of adherence, serum resistance and ompW in Acinetobacter baumannii(Public Library of Science, 2024) Menekşe, Şirin; Department of Industrial Engineering; Department of Industrial Engineering; Boral, Jale; Vatansever, Cansel; Özcan, Gülin; Keske, Şiran; Gönen, Mehmet; Can, Füsun; Koç Üniversitesi İş Bankası Yapay Zeka Uygulama ve Araştırma Merkezi (KUIS AI)/ Koç University İş Bank Artificial Intelligence Center (KUIS AI); College of Engineering; Graduate School of Health Sciences; School of Medicine; Koç University HospitalBackground Colistin resistance in Acinetobacter baumannii is an emerging problem that limits antimicrobial therapy options. Materials & methods We isolated two pairs of colistin susceptible and colistin-resistant A. baumannii (K1007/ K1006 and K408/K409) from two patients diagnosed with carbapenem-resistant A. baumannii infection. Colistin susceptible isolates were exposed to in vitro colistin induction for 50 generations. The selected cell populations were subjected to DNA and RNA sequencing and phenotypic assays. Results In the in vitro induction assay, K408 gained colistin resistance on the corresponding day of clinical resistance (K408-G25) and got resensitized to colistin in the consecutive generation (K408-G26). A significant upregulation of ompW, ata, adeFGH genes on K408-G25 was followed by a downregulation upon resensitization to colistin (G26). Despite the upregulation of the ompW gene in transcriptomic analysis, the ompW protein disappeared on K408-G25 and recovered in the resensitized generation (G26). In parallel, disrupted cell membrane integrity recovered in K408-G26. In the K408-G25, downregulation of pbpG and upregulation of pbp1a/pbp3 genes decreased serum-resistance which was reversed in the resensitized generation (G26). The K1007 did not gain colistin resistance amongst 50-generations, however, the generation corresponding to clinical resistance day (K1007-G9) had a similar trend with K408-G25. The clinical colistin-resistant K409 and K1006 had SNPs on pmrA and pmrB genes. Conclusion In this study, we observed that A. baumannii regulates adhesion, efflux pumps and serum-resistance associated genes as an early response to colistin stress. Besides, the ompW protein disappears in the cell membrane of colistin resistant cells which recovers after resensitization to colistin. The lack of ompW protein in colistin-resistant cells should be taken into consideration for escape mutants in development of antivirulence vaccination or treatment options. © 2024 Public Library of Science. All rights reserved.Publication Metadata only Prof. Dr. Kenan Midilli (1963-2022) Anısına(DOC Design Informatics Co Ltd, 2022) Aygun, Gokhan; Aygun, Pakize; Azap, Alpay; Benzonana, Nur; Kurt-Azap, Ozlem; Kuskucu, Mert Ahmet; Simsek-Yavuz, Serap; Turan, Ayfer; Can, Füsun; Ergönül, Önder; Koç Üniversitesi İş Bankası Enfeksiyon Hastalıkları Uygulama ve Araştırma Merkezi (EHAM) / Koç University İşbank Center for Infectious Diseases (KU-IS CID); School of MedicineN/APublication Metadata only Two pioneers of women medical doctors(Doc Design Informatics Co Ltd, 2024) Azap, Özlem Kurt; Can, Füsun; Koç Üniversitesi İş Bankası Enfeksiyon Hastalıkları Uygulama ve Araştırma Merkezi (EHAM) / Koç University İşbank Center for Infectious Diseases (KU-IS CID); School of MedicineN/APublication Open Access Determination of carbapenem resistance in gram-negative bacteremia in the burn intensive care unit(Bilimsel Tıp Yayınevi, 2024) Çaydaşı, Özge; Benzonana, Nur; Hacıseyitoğlu, Demet; Gideroğlu, Kaan; Özer, Raşit Serdar; Can, Füsun; Ergönül, Önder; School of MedicineIntroduction: Gram-negative sepsis constitutes a significant cause of mortality and morbidity in the burns intensive care unit (BICU). In the current era of a global antibiotic resistance crisis, it is imperative to monitor the geographical distribution of carbapenem-resistant microorganisms. Therefore, we aimed to determine the resistance rates of gram -negative microorganisms and the mechanisms that cause carbapenem resistance in the BICU. Materials and Methods: From February 2015 to February 2016, we conducted a patient follow-up in the BICU of our hospital. Carbapenem-resistant gram -negative bacteria were identified in the blood cultures of 39 patients. Forty-nine episodes of bacteremia in 39 patients were included in this study. The study assessed the relationship between patients' demographic characteristics, signs associated with burn, abbreviated burn severity index (ABSI), and acute physiology and chronic health evaluation (APACHE -II) score with mortality. The carbapenemase enzyme was identified using genotypic methods. Carbapenemase gene regions in DNA samples were investigated by multiplex polymerase chain reaction (PCR). Results: Out of the total cases, 77% were male patients with a median age of 36 (1-89) years. Flame burn was detected as the most common. The mortality rate in this study was 43%. Statistically significant relationships were identified between ABSI and APACHE -II scores with mortality. Of the blood culture isolates, 27 (55%) were Acinetobacter baumannii, 17 (34%) Pseudomonas aeruginosa, three (6%) Klebsiella pneumoniae, one (2%) Enterobacter cloacae, one (2%) Proteus vulgaris. OXA-23 enzyme was detected in all of the A. baumannii strains. KPC enzyme was detected in one of the P. aeruginosa strains. NDM was found in two of the K. pneumoniae strains, and NDM-1 and OXA-48 enzymes were detected together in one. NDM enzyme was detected in the E. cloacae strain. Conclusion: In this study, it was observed that A. baumannii strains are the most prevalent agents causing bacteremia in the burns intensive care unit (BICU). While the OXA-23 gene was detected in all of the A. baumannii strains, the Carbapenemase enzyme was not detected in 94% of the P. aeruginosa strains. It is anticipated that these data will guide the selection of antibiotics in the burns intensive care unit (BICU).Publication Metadata only Surveillance of respiratory viruses by aerosol screening in indoor air as an early warning system for epidemics(WILEY, 2024) Palaoğlu, Erhan; Besli, Yeşim; Eren, Zeynep Bengi; Vatansever, Cansel; Kabadayı, Berk; Haykar, Bedirhan; Kuloğlu, Zeynep Ece; Ay, Sedat; Nurlybayeva, Kamila; Eyikudamacı, Gül; Barlas, Tayfun; Kuşkucu, Mert Ahmet; Ergönül, Önder; Can, Füsun; Koç Üniversitesi İş Bankası Enfeksiyon Hastalıkları Uygulama ve Araştırma Merkezi (EHAM) / Koç University İşbank Center for Infectious Diseases (KU-IS CID); School of Medicine; Graduate School of Health SciencesThe development of effective methods for the surveillance of seasonal respiratory viruses is required for the timely management of outbreaks. We aimed to survey Influenza-A, Influenza-B, RSV-A, Rhinovirus and SARS-CoV-2 surveillance in a tertiary hospital and a campus over 5 months. The effectiveness of air screening as an early warning system for respiratory viruses was evaluated in correlation with respiratory tract panel test results. The overall viral positivity was higher on the campus than in the hospital (55.0% vs. 38.0%). Influenza A was the most prevalent pathogen in both locations. There were two influenza peaks (42nd and 49th weeks) in the hospital air, and a delayed peak was detected on campus in the 1st-week of January. Panel tests indicated a high rate of Influenza A in late December. RSV-A-positivity was higher on the campus than the hospital (21.6% vs. 7.4%). Moreover, we detected two RSV-A peaks in the campus air (48th and 51st weeks) but only one peak in the hospital and panel tests (week 49). Although rhinovirus was the most common pathogen in panel tests, rhinovirus positivity was low in air samples. The air screening for Influenza-B and SARS-Cov-2 revealed comparable positivity rates with panel tests. Air screening can be integrated into surveillance programs to support infection control programs for potential epidemics of respiratory virus infections except for rhinoviruses. © 2024 The Author(s). Environmental Microbiology Reports published by John Wiley & Sons Ltd.Publication Open Access Dysbiosis in pregnant mice induced by transfer of human vaginal microbiota followed by reversal of pathological changes in the uterus and placenta via progesterone treatment(BMC, 2024) Department of Computer Engineering;Department of Chemical and Biological Engineering; Kuyucu, Gülin Özcan; Talay, Zeynep Gülce; Paerhati, Erxiati; Eren, Özgür Can; Coşkun, Nilhan; Şahin, Deniz; Alnajjar, Iman; Albayrak, Özgür; Gürsoy, Attila; Keskin, Özlem; Çelik, Ebru; Can, Füsun; Koç Üniversitesi İş Bankası Enfeksiyon Hastalıkları Uygulama ve Araştırma Merkezi (EHAM) / Koç University İşbank Center for Infectious Diseases (KU-IS CID); Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); Graduate School of Health Sciences; College of Engineering; School of Medicine; Koç University HospitalObjective The vaginal microbiota dysbiosis induces inflammation in the uterus that triggers tissue damage and is associated with preterm birth. Progesterone is used to prevent labor in pregnant women at risk of preterm birth. However, the mechanism of action of progesterone still needs to be clarified. We aimed to show the immunomodulatory effect of progesterone on the inflammation of uterine tissue triggered by dysbiotic vaginal microbiota in a pregnant mouse model.Methods Healthy (n = 6) and dysbiotic (n = 7) vaginal microbiota samples isolated from pregnant women were transferred to control (n = 10) and dysbiotic (n = 14) pregnant mouse groups. The dysbiotic microbiota transferred group was treated with 1 mg progesterone (n = 7). Flow cytometry and immunohistochemistry analyses were used to evaluate inflammatory processes. Vaginal microbiota samples were analyzed by 16 S rRNA sequencing.Results Vaginal exposure to dysbiotic microbiota resulted in macrophage accumulation in the uterus and cellular damage in the placenta. Even though TNF and IL-6 elevations were not significant after dysbiotic microbiota transplantation, progesterone treatment decreased TNF and IL-6 expressions from 49.085 to 31.274% (p = 0.0313) and 29.279-21.216% (p = 0.0167), respectively. Besides, the macrophage density in the uterus was reduced, and less cellular damage in the placenta was observed.Conclusion Analyzing the vaginal microbiota before or during pregnancy may support the decision for initiation of progesterone therapy. Our results also guide the development of new strategies for preventing preterm birth.Publication Metadata only The vaginal microbiome composition during pregnancy in a region compromising different ethnic origins(Springer Heidelberg, 2024) Department of Computer Engineering;Department of Chemical and Biological Engineering; Kuyucu, Gülin Özcan; Vatansever, Cansel; Paerhati, Erxiati; Turğal, Mert; Gürsoy, Tuğba; Çekiç, Sebile Güler; Ünal, Ceren; Özek, Murat Aykut; Gürsoy, Attila; Keskin, Özlem; Can, Füsun; Çelik, Ebru; Koç Üniversitesi İş Bankası Enfeksiyon Hastalıkları Uygulama ve Araştırma Merkezi (EHAM) / Koç University İşbank Center for Infectious Diseases (KU-IS CID); Graduate School of Health Sciences; Graduate School of Sciences and Engineering; School of Medicine; College of Engineering; Koç University HospitalBackgroundThe vaginal microbiota plays a significant role in pregnancy outcomes and newborn health. Indeed, the composition and diversity of the vaginal microbiota can vary among different ethnic groups. Our study aimed to investigate the composition of the vaginal microbiome throughout the three trimesters of pregnancy and to identify any potential variations or patterns in the Turkish population compromising mixed ethnicities.MethodWe conducted a longitudinal study to characterize the vaginal microbiota of pregnant women. The study included a total of 25 participants, and the samples were collected at each trimester: 11-13 weeks, 20-24 weeks and 28-34 weeks gestation.ResultsLactobacillus species were consistently found to be dominant in the vaginal microbiota throughout all trimesters of pregnancy. Among Lactobacillus species, L. crispatus had the highest abundance in all trimesters (40.6%, 40.8% and 44.4%, respectively). L. iners was the second most prevalent species (28.5%, 31% and 25.04, respectively). Our findings reveal that the dominant composition of the vaginal microbiota aligns with the CST-type I, commonly observed in the European population.ConclusionsThis suggests that there are shared mechanisms influencing the microbial communities in the vagina, which are likely influenced by factors such as genetics, lifestyle, and cultural behaviors rather than ethnicity alone. The complex interplay of these factors contributes to the establishment and maintenance of the vaginal microbiota during pregnancy. Understanding the underlying mechanisms and their impact on vaginal health across diverse populations is essential for improving pregnancy outcomes.The study was approved by the Koc University Ethical Committee (no:2019.093.IRB2.030) and registered at the clinical trials.ConclusionsThis suggests that there are shared mechanisms influencing the microbial communities in the vagina, which are likely influenced by factors such as genetics, lifestyle, and cultural behaviors rather than ethnicity alone. The complex interplay of these factors contributes to the establishment and maintenance of the vaginal microbiota during pregnancy. Understanding the underlying mechanisms and their impact on vaginal health across diverse populations is essential for improving pregnancy outcomes.The study was approved by the Koc University Ethical Committee (no:2019.093.IRB2.030) and registered at the clinical trials.