İstanbul Sağlık ve Teknoloji Üniversitesi Kurumsal Akademik Arşivi
DSpace@İSTÜN, Üniversite mensupları tarafından doğrudan ve dolaylı olarak yayınlanan; kitap, makale, tez, bildiri, rapor, araştırma verisi gibi tüm akademik kaynakları uluslararası standartlarda dijital ortamda depolar, Üniversitenin akademik performansını izlemeye aracılık eder, kaynakları uzun süreli saklar ve telif haklarına uygun olarak Açık Erişime sunar.
Güncel Gönderiler
Ozone treatment attenuates neuroinflammation and alters miRNA expression in a rat model of post-traumatic epilepsy
(Springer Nature Link, 2026) Demir, Hüseyin; Demirtaş, Cumaali; Yıldırım, Hava; Demir, Ecem; Kıroğlu Uzun, Sezin; Şevgin, Kübra; Beyaztaş, Hakan; Güler, Eray Metin; Hekimoğlu, Gulam; Çoşkunpınar, Ender Mehmet; Şanlıer, Nafiye; Yıldırım, Mehmet
The aim of this study was to investigate the effects of intraperitoneal ozone therapy in a post-traumatic epilepsy (PTE) model. An in vivo PTE model was established in male Sprague–Dawley rats, which were randomised to control (n=8), PTE (n=10), and PTE+Ozone (n=10) groups. 0.7 mg/kg ozone was administered intraperitoneally for 3 consecutive days. Seizure activity was video recorded for 120 min and evaluated for latency, frequency, duration, and severity. Behav ioral assessments of locomotor activity, anxiety, and spatial memory were conducted using open field, elevated plus, and radial arm maze tests on days 4–6 after the first ozone application. Blood and brain tissues were collected for biochemical assays (SUR1, TRPM4, IL-1β, IL-6, TNF-α, TAS, TOS, OSI, thiol–disulfide homeostasis), histological analyses (H&E, Cresyl Violet, and 8-OHdG immunostaining), and qRT-PCR of epilepsy-related miRNAs. Significant differences were observed among the groups for all serum and brain biomarkers (p<0.001). The PTE group showed marked increases in SUR1, TRPM4, IL-1β, IL-6, TNF-α, TOS, OSI, TT, NT, and DIS levels, accompanied by a decrease in TAS. Ozone treatment partially reversed these changes by reducing cytokine and oxidative stress markers, improving thiol–disulfide balance, and restoring TAS levels. Behavioural testing revealed beneficial effects of ozone, including reduced immobil ity, fewer errors in the radial arm maze, and increased open-arm exploration. Although seizure severity, latency, and duration were not significantly altered, seizure frequency showed a decreasing trend (p=0.067). Immunofluorescence for 8-OHdG revealed increased hippocampal oxidative DNA damage in the PTE group, which was attenuated following ozone treatment. Analysis of miRNA expression revealed downregulation in the PTE group, whereas ozone treatment resulted in overall upregulation. There was no statistically significant difference between miRNA expression results and the PTE+Ozone group (p=0.056–0.076). Ozone therapy mitigated oxidative stress and inflammation, improved redox homeostasis, enhanced cognitive and locomotor performance, and reduced hippocampal DNA damage in the PTE model. Furthermore, the observed upregulation of specific miRNAs following ozone treatment highlights a potential molecular mechanism contributing to its neuroprotective effects.
Clinical and molecular features of ovarian stimulation in peripubertal girls with mosaic turner’s syndrome
(Oxford University Press, 2026) Öktem, Özgür; Kalajahi, Hesam Ghafouri; Esmaeilian, Yashar; Benlioğlu, Can; Hela, Francesko; Yusufoğlu, Sevgi; Kalkan, Üzeyir; Turan, Volkan; Ata, Barış
STUDY QUESTION: Do peripubertal girls with mosaic Turner’s syndrome (TS) respond to ovarian stimulation (OS) for oocyte freezing as adult women with normal ovarian reserve? SUMMARY ANSWER: Clinical and molecular reproductive/endocrine features of OS in these patients are similar to those of adult females. WHAT IS KNOWN ALREADY: OS for oocyte freezing is quite a new concept in peripubertal and young adolescent girls with TS be cause ovarian tissue cryopreservation (OTC) does not have proven efficacy, likely due to already diminished ovarian reserve and ac celerated follicle atresia. No data are available in the literature regarding the molecular IVF characteristics of these cycles in this group of patients. We aimed to address this issue in the current study by analyzing gonadotropin receptor expression, response to gonadotropins, and steroidogenic function at the molecular level in four peripubertal patients aged 9, 12, 13, and 15 in comparison to control adult females with normal ovarian reserve undergoing OS for male factor infertility. STUDY DESIGN, SIZE, DURATION: This is a clinical and research study that simultaneously analyzes the clinical and molecular characteristics of OS in peripubertal young girls with TS between 2021 and 2023 at a university hospital and translational re search center. PARTICIPANTS/MATERIALS, SETTING, METHODS: All participants underwent OS using a progestin-primed protocol with recombi nant forms of FSH and LH, and final maturation was induced with recombinant hCG. Control patients who had normal ovarian re serve and underwent OS for male factor infertility were randomly recruited during the study period to simultaneously compare and analyze the clinical and molecular OS characteristics of the peripubertal TS cases. Luteinized mural granulosa cells obtained during oocyte retrieval procedures were used for the experiments. Cell culture, quantitative real-time PCR, immunoblotting, confocal time lapse live-cell imaging, and hormone assays were used. MAIN RESULTS AND THE ROLE OF CHANCE: All TS cases responded to gonadotropin stimulation. Nine mature oocytes were re trieved and vitrified in the 9-year-old prepubertal mosaic TS case after four cycles of OS with r-FSH (300 IU) and r-LH (150 IU)/day after a mean stimulation period of 9.72 ± 2.1 days. Eight mature oocytes were retrieved in the case aged 13 after three rounds of OS. The other cases, aged 12 and 15, underwent only one cycle of OS, and two mature oocytes from each were retrieved. The expression of FSH/LH receptors and steroidogenic enzymes, basal and gonadotropin-induced up-regulation in the expression of the steroidogenic enzymes, and estradiol and progesterone productions of the GCs of the TS patients were similar to those of adult control patients. Confocal immunofluorescence microscopy and live imaging revealed no differences in cholesterol uptake/trafficking or in staining patterns of the steroidogenic enzymes and their co-localization with mitochondria and cholesterol-laden lipid droplets. LIMITATIONS, REASONS FOR CAUTION: Findings were obtained from a limited number of mosaic TS patients. It is unclear if these findings are reproducible in non-mosaic peripubertal cases. Furthermore, no data are available yet regarding the post-thaw survival, fertilization, embryo development competency, euploidy status, and obstetrical outcomes of the vitrified oocytes of these patients. WIDER IMPLICATIONS OF THE FINDINGS: This study provides reassuring clinical and molecular evidence that OS for oocyte freez ing can be an option in young girls with mosaic TS who are not ideal candidates for OTC due to diminished ovarian reserve. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the School of Medicine, the Graduate School of Health Sciences, and the Research Center for Translational Medicine (KUTTAM) at Koc¸ University. The authors declare no competing interests. TRIAL REGISTRATION NUMBER: Not applicable.
Evaluating a pathogen-specific IgG binding assay for rapid detection of healthcare-associated infections
(Nature Portfolio, 2026) Karakullukçu, Asiye; Akker, Mustafa; Kuşkucu, Mert Ahmet; Aygün, Gökhan; Dikmen, Yalım
Rapid and accurate diagnosis of healthcare-associated infections (HAIs) is an unmet need for improving outcomes in intensive care units (ICUs). Traditional culture-based methods, while the gold standard, are time-consuming and can delay therapeutic interventions. In this study, we evaluated the diagnostic utility of pathogen-specific immunoglobulin G (IgG) binding levels using an enzyme-linked immunosorbent assay (ELISA). We measured IgG binding against pathogens including Acinetobacter baumannii, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Enterococcus faecium, and Staphylococcus aureus. Diagnostic performance was evaluated through receiver operating characteristic (ROC) curve analysis, with culture results as the reference. The assay demonstrated an overall diagnostic accuracy of 83.2%, with a sensitivity of 85.4%, a specificity of 81.4%, and an area under the curve (AUC) of 0.910. Pathogen-specific cutoff values ranged from 0.918 to 1.534. Especially, A. baumannii showed the highest performance metrics, achieving a sensitivity of 94.7%, a specificity of 93.6%, and an AUC of 0.975. The pathogen-specific IgG binding levels can offer a novel and effective diagnostic tool for the initial assessment of HAIs, enhancing early detection and improving patient management across healthcare settings.
Kontrollü solunum teknikleri, diyafram aktivasyonu ve gevşeme egzersizlerinin nöroplastisite üzerine etkisi
(Nobel Tıp Kitabevleri, 2025) Şahin, Okan; Gür Özmen, Selen; Köseoğlu Kurt, Aygül
Solunum; fiziksel, ruhsal, zihinsel, davranışsal çıktılar oluşturan, karmaşık fizyolojik süreçleri barındıran ve istemli olarak da kontrol edilebilen otonomik bir fonksiyon olarak tanımlanmaktadır. Solunum ritmi ve derinliği gibi solunum paternini belirleyen parametrelerin, bireyin duygusal ve zihinsel durumu ile etkileşim halinde olması bu kompleks olguyu derinleştirmektedir. Bu nedenle solunum hem fizyolojik mekanizmalarla hem de davranışsal çıktılarla tanımlanan bütünsel bir fenomen olarak kabul edilir (Del Negro vd., 2018). Başka bir deyişle, solunum oksijen-karbondioksit değişimi dışında, kapsamlı bir dönüşüm ve boyutsal bir değişim olarak düşünülür. Ruh, zihin ve beden arasında bir bağlantı kurduğuna inanılmaktadır (Önder, 2019).
Green synthesis of titanium dioxide nanoparticles using a deep eutectic solvent-based extract of Prunus spinosa L. for photocatalytic degradation of 2,4-dichlorophenoxyacetic acid
(Elsevier, 2026) Bozkurt, Rabia Nur; Şahin, Selin; Cadar, Oana
In this study, polyphenol-rich extract obtained from Prunus spinosa L. fruit using choline chloride/lactic acid (1/ 1) deep eutectic solvent was used as reducing, stabilizing and capping agent in the green synthesis of TiO2 nanoparticles (TiO2-NPs). The extraction system using a homogenizer was optimized using the Response Surface Methodology (RSM). The conditions providing the highest efficiency for total phenolic content (40.885 mg-GAE/ g-FF) and antioxidant activity (86.22%) were determined as 46.179% (v/v) water ratio to DES, 1.478 g sample amount and 65.513 s extraction time. UV–Vis DRS, PL, SEM-EDX, HR-TEM-EDX, FTIR, XRD, DLS, and Zeta Potential analyses revealed that the TiO2-NPs had a band gap of 2.8 eV, a spherical morphology, nanosize, and high crystalline purity. Comparative DLS and zeta potential analyses of aqueous extract and DES-based systems showed that the DES-based environment yields smaller and more stable TiO2-NPs. Furthermore, TiO2-NPs showed notable antioxidant activity, with an IC50 value of 52.4 μg/mL. The TiO2-NPs were utilized as photo catalysts to degrade 2,4-dichlorophenoxyacetic acid (2,4-D). Photocatalytic tests showed the highest efficiency, achieving 66.9% degradation of an 80 mg/L 2.4-D solution with 50 mg of TiO2-NPs at pH 5.5 within 120 min. The photocatalyst remained stable after three cycles. A nanomaterial has been sustainably created using an extremely environmentally friendly method for photocatalytic pollutant destruction.
