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
Phenol for pilonidal sinus disease: A nationwide survey of practice patterns and safety gaps among surgeons in Türkiye
(BioMed Central, 2026) Ergüder, Ender; Yahya, Duha; Turan, Ersin; Şimşek, Gürcan; Bulut, Sezer; Arslan, Çiğdem
Background Phenol is widely used as a minimally invasive treatment for pilonidal sinus disease (PSD); however, its clinical application is characterized by substantial heterogeneity in indications, technique, dosing, and safety practices. Despite its routine use in outpatient settings, standardized safety frameworks addressing occupational exposure, environmental controls, and dose documentation are lacking. These gaps may have important implications for both patient outcomes and workplace safety. This nationwide survey aimed to characterize real-world phenol practice patterns among surgeons in Türkiye, with a particular focus on safety infrastructure, exposure control measures, and clinical decision-making. Methods A nationwide, internet-based, cross-sectional survey of surgeons managing PSD in Türkiye (July 8– August 15, 2025), aligned with CHERRIES. The 38-item instrument captured demographics; workload/experience; environmental controls (ventilation), institutional exposure-prevention policies, and personal protective equipment (PPE); patient-side protection strategies; phenol procurement, formulation/concentration, and dosing; treatment planning; and outcomes/perceptions. Descriptive statistics summarized item-level responses. Results A total of 132 surgeons provided responses. 81.1% evaluated more than 30 PSD patients annually, and 48.5% conducted more than 30 phenol procedures per year. Surgeons frequently procured phenol from external pharmacies (36.4%); crystalline phenol predominated (77.3%); 50.8% did not know the concentration (most reported 99.9%); and only 7.6% measured dose per procedure. The majority of surgeons performed 2 to 3 sessions (69.0%) at intervals of 2 to 3 weeks (38.6%). Key safety gaps were identified: only 34.8% reported dedicated ventilation, 53.0% reported none, and 62.1% had no institutional exposure-prevention policy. Routine mask use was reported by 53.8% (primarily surgical masks); additional PPE beyond mask and gloves was used by 22.0% (gowns 51.7%, eye protection 48.3% among those reporting). Patient-side skin protection was common (81.3%). Adverse events in patients were recorded at a rate of 20.5%, with skin burns being the most prevalent, while operator adverse effects occurred at a rate of 5.3%. Despite these gaps, perceived safety was relatively high (patients 83.3%, operators 68.9%), and 89.4% would personally choose phenol if affected. Conclusions Findings support a safety-first national framework specifying permissible formulations/concentrations, mandating dose documentation and skin-protection protocols, and implementing a core safety bundle (effectiveventilation, written exposure-control policies/checklists, and PPE including eye protection). Prospective exposure monitoring with standardized outcomes is warranted.
Synergistic cytotoxicity of bentonite–zeolite 4A nanocomposite in human melanoma cells
(Taylor & Francis, 2026) Duman, Nilay; Evcin, Atilla; Çelik, Sefa; Oraloğlu, Göktürk; Caner, Ayşe
The cytotoxic effects of bentonite and zeolite 4A nanoparticles (NPs), as well as their nanocomposite (NC), were investigated in human melanoma (G361) cells. Although both materials have demonstrated anticancer potential, their effects on melanoma remain insufficiently explored. This study aimed to evaluate the cellular responses induced by bentonite and zeolite 4A NPs, individually and in combination, in G361 cells. Methods: Physicochemical characterization was performed using X-ray diffraction (XRD), X-ray fluorescence (XRF), and scanning electron microscopy (SEM). IC₅₀ values were determined for bentonite NPs, zeolite 4A NPs, and the NC. Cell viability was assessed using the MTT assay, while apoptosis was evaluated through caspase-3 activity measured by ELISA. Results: All treatments exhibited dose-dependent cytotoxicity in melanoma cells. Notably, the NC demonstrated a strong synergistic interaction, enhancing cytotoxic effects and enabling reduced effective concentrations. Despite the pronounced cytotoxicity observed in the NC group, no significant increase in caspase-3 activity was detected compared to control. These findings suggest the involvement of caspase-independent cell death mechanisms, particularly necrotic or non-classical apoptotic processes. Conclusion: The bentonite/zeolite 4A nanocomposite exerts synergistic cytotoxic effects in melanoma cells. While the results highlight its therapeutic potential, further mechanistic studies are required to clarify the underlying pathways prior to clinical translation.
Aesthetic preformed paediatric crowns in primary incisors: A bibliometric study and critical analysis
(Springer Nature Link, 2026) Taşdemir, Tülin; Erbaş Ünverdi, Gizem; Çehreli, Zafer Cavit
Purpose The aim of this bibliometric study was to assess clinical research regarding preformed crowns used for the treat ment of primary anterior teeth. Methods A search was conducted in the Web of Science Core Collection (WoSCC) for publications on preformed crowns for primary anterior teeth, and was completed in a single day (August 8, 2025), identifying 379 articles. After filtering for original research and case report/series published in English, 40 relevant articles were selected for review. These publications were evaluated based on annual publication trends, study designs, journals, citation counts, authors, and keywords, using the ‘biblioshiny’ program in RStudio. Additionally, the review included critical analysis of articles with full texts to collect detailed information on study design, sample size, and clinical outcomes. Results The review of 40 articles over three decades showed a 4.57% annual increase in publication number on preformed crowns for primary anterior teeth, especially since 2012, with USA authors leading. The data reveal temporal trends in preveneered preformed metal crowns for anterior primary teeth, strip crown success, zirconia crowns (gingival health, qual ity of life and parental satisfaction comparisons), and preformed crowns for primary anterior teeth after pulpal treatment. Amongst them, the journal “Pediatric Dentistry” had published the most papers. Recent studies highlighted zirconia crowns’ high retention and gingival health benefits, whilst strip crowns showed lower durability. Conclusion For anterior primary teeth, that zirconia crowns offered high durability, aesthetics, and parental satisfaction. The heterogeneity of study designs underscores the necessity for more comprehensive research to inform paediatric dentistry practices.
Novel peripheral and nonperipheral tetrasubstituted zinc(II) phthalocyanines with ester-containing coumarin substituents: Synthesis, characterization, aggregation, thermal and antioxidant studies
(Springer Nature Link, 2026) Özgül Artuç, Gamze
In this study, nonperipheral and peripheral zinc metallophthalocyanine compounds substituted with coumarin contain ing ester groups were synthesized, their chemical structures were characterized, and their aggregation behaviours were investigated. Their antioxidant properties were investigated using 1,1-diphenyl-2-picrylhydrazine (DPPH). The antioxidant activity studies revealed that the peripheral substituted phthalocyanine compound had higher antioxidant activity than the nonperipheral phthalocyanine compound. Their thermal analysis were investigated using thermal gravimetric analy sis. Thermal analysis studies concluded that the synthesized zinc metal phthalocyanine compounds are thermally stable compounds.
Nicotinic acid–modified chitosan nanoparticles for enhanced resveratrol delivery and anticancer activity
(Wiley, 2026) Şentürk, Sema; Kaplan, Özlem; Bal, Kevser; Küçükertuğrul Çelik, Sibel; Gökşen Tosun, Nazan; Gök, Mehmet Koray
This study focused on functionalizing chitosan with nicotinic acid, the active form of vitamin B3, to obtain a new derivative (ChiNico) with enhanced solubility at physiological pH, improved proton buffering capacity, and in vitro anticancer activity, and to develop resveratrol-loaded nanoparticles (nChiNico-RES) for enhanced anticancer performance. Chitosan was modified through EDC-mediated amidation, and successful conjugation was confirmed by FTIR, 1H NMR, and GPC/SEC analyses. Nicotinic acid grafting increased molecular weight, introduced characteristic amide signals, improved solubility at physiological pH, and enhanced proton buffering capacity. Nanoparticles were prepared by ionotropic gelation and showed sizes of 100–140nm, PDI values below 0.4, and a positive surface charge of +18 to +20mV. Blank nanoparticles exhibited minimal cytotoxicity, while resveratrol-loaded formulations demonstrated significant anticancer activity in HeLa cervical cancer cells and HT-29 human colon adenocarcinoma cell line. Notably, nChiNico-RES reduced HeLa and HT-29 cell viability more effectively than free resver atrol and nanoparticles based on unmodified chitosan, indicating an additive contribution from nicotinic acid. In contrast, the cytotoxic effect on healthy BJ fibroblasts remained considerably lower, supporting the biocompatibility and selective potential of the system. Overall, nicotinic acid modification improves chitosan's carrier performance and offers a novel strategy by combin ing two natural bioactive molecules within a single nanoparticle platform.
