İstanbul Galata Üniversitesi Kurumsal Akademik Arşivi
DSpace@Galata, İstanbul Galata Üniversitesi 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
Endocrine and metabolism modulating effects of paracetamol: From in vitro signaling to in vivo metabolic reprogramming in male mice
(Elsevier, 2026) Entezari, Bita; Bozdağ, Deniz; Buhur, Aylin; Sabuncuoğlu, Suna; Yavaşoğlu, Altuğ; Orhan, Hande Gürer
Obesity is a major global health challenge associated with a cluster of comorbidities, including metabolic syndrome and type 2 diabetes, necessitating a deeper understanding of the environmental factors contributing to this epidemic. This study investigated the in vitro adipogenic/lipogenic potential of paracetamol and its in vivo endocrine and metabolic modulating effects following prenatal exposure. Using the 3T3-L1 preadipocyte model, cells were exposed to paracetamol at physiologically relevant concentrations. Results demonstrated that paracetamol promoted lipid accumulation and upregulated G3PDH activity. Furthermore, low concentrations significantly increased the protein expression of key adipogenic regulators (PPARγ, C/EBPα, LPL, and SREBP1), suggesting interference with transcriptional cascades governing adipogenesis and lipogenesis. To assess in vivo effects, pregnant CD1 mice were exposed to paracetamol at three human relevant doses (Cmax/10, Cmax, and Cmax×10). In male F1 offspring, prenatal exposure resulted in increased anogenital distance and a higher incidence of sperm morphological abnormalities, indicating reproductive developmental alterations despite unchanged circulating hormone levels. Metabolically, offspring exhibited dyslipidemia characterized by elevated serum triglycerides and total cholesterol. Although body weight and glucose tolerance remained unaffected, lipidomic profiling of epididymal adipose tissue revealed pronounced remodeling, including the accumulation of neutral lipids and altered membrane phospholipid composition. This was accompanied by the upregulation of the adipogenic genes Pparγ, Lpl, and Fasn in adipose tissue. Collectively, these findings suggest that paracetamol may act as an endocrine modulator and metabolic disruptor when exposed prenatally, inducing latent metabolic dysregulation that may predispose offspring to metabolic syndrome later in life, even in the absence of overt obesity
Comparison of tensile bond strengths of different impression materials used with custom trays fabricated by 3D printing
(2026) Topalan, Onur; Özyılmaz, Özgün Yusuf
Background: This study aimed to evaluate and compare the tensile bond strength between four different impression materials and custom trays fabricated using various photopolymer-based threedimensional (3D) printing materials and one conventional method. Additionally, the effect of three surface treatments on bond strength was investigated. Methods: A total of 288 custom tray specimens were fabricated using four different techniques: Stereolithography (SLA), liquid crystal display (LCD), digital light processing (DLP), and a conventional light-cured urethane dimethacrylate (UDMA)-based acrylic. Each tray type was subjected to three surface treatments: adhesive-only, perforated-only, and perforated + adhesive. Four elastomeric impression materials were tested: polyvinylsiloxane, condensation silicone, polyether, and vinylsiloxanether. A standardized CAD model was used for all trays. The impression materials were applied onto the tray surfaces, and tensile bond strength was tested using a universal testing machine. Each condition was tested with six replicates (n = 6). Data were recorded in Newtons and converted to megapascal (MPa) using a standardized bonding surface area of 825 mm². Three-way ANOVA and Tukey’s post-hoc tests were conducted (α=0.05). Results: All three independent variables - printing technique, surface treatment, and impression material - had a statistically significant effect on tensile bond strength (p < 0.001). The highest mean bond strength (0.272 MPa) was observed with the DLP-printed tray using perforatedonly and polyether impression material. The lowest value (0.018 MPa) was found with the same tray type and surface treatment, but with condensation silicone. Among surface treatments, adhesive-only and adhesive + perforated trays showed significantly higher bond strengths compared to perforated-only groups (p = 0.001). Polyether showed significantly higher bond strength than all other impression materials, while condensation silicone yielded the lowest. Conclusions: Within the limitations of this in vitro study, tray fabrication method and surface treatment significantly influenced bonding with impression materials. The present findings may provide useful preliminary data for future clinical investigations evaluating retention characteristics of 3D-printed custom trays.
Volumetric Three-Dimensional Evaluation of the Pharyngeal Airway After Orthognathic Surgery in Patients with Skeletal Class III Malocclusion
(MDPI, 2025) Öz, Aslıhan Zeynep; El, Hakan; Öz, Abdullah Alper; Palemo, Juan Martin
Background: Orthognathic surgery significantly alters the dimensions of the pharyngeal airway. This study’s objective was to assess alterations in the pharyngeal airway volume via cone-beam computed tomography (CBCT) after orthognathic surgery in patients with skeletal Class III malocclusion. Methods: This retrospective study analyzed CBCT images from 23 patients with skeletal Class III malocclusion (13 females, 10 males), who were categorized into two groups based on the surgical approach: double-jaw and single-jaw surgery. The double-jaw group included 13 patients who underwent bilateral sagittal split osteotomy (BSSO) and Le Fort I osteotomy, whereas the single-jaw group included of 10 patients who had underwent BSSO only. CBCT images were evaluated both before surgery and at a minimum of three months after surgery. The oropharyngeal volume (OP), nasopharyngeal volume (NP), total airway volume, posterior airway space (PAS), and the most constricted area at the base of the tongue (minAx) were measured. Statistical analyses were performed using either paired t-tests or Wilcoxon signed-rank tests depending on data normality, with a significance level set at p < 0.01. Results: In the double-jaw group, a significant volumetric increase was observed in the nasopharynx (5316 ± 1948 mm3 to 6064 ± 1899 mm3 ; p = 0.010) and oropharyngeal volume decreased from 17,097 ± 5675 mm3 to 14,290 ± 5835 mm3 ; however, this reduction was not statistically significant (p = 0.017). In contrast, the single-jaw group showed a significant reduction in oropharyngeal volume from 15,620 ± 5040 mm3 to 12,444 ± 4701 mm3 (p = 0.010), with no significant change in nasopharyngeal volume (p = 0.551). Total airway volume significantly decreased only in the single-jaw group (from 20,452 ± 7754 mm3 to 16,846 ± 6529 mm3 , p = 0.010). Additionally, both groups exhibited marked decreases in PAS and minimum axial area values (all p < 0.01). Conclusions: Orthognathic surgery led to a significant volumetric increase in the nasopharynx in the double-jaw group, whereas the oropharynx volume significantly decreased only in the single-jaw group. Additionally, both surgical approaches resulted in a marked reduction in PAS and minimum axial area values, highlighting a notable impact on posterior airway dimensions.
A cross-sectional study on the determinants of parents' giving vitamin C to their children engaged in sportive activities
(Campus EDUCA SPORTIS S.L., 2026) Kuyucu, Mihalis; Yücel, Ali Serdar; Korkmaz, Murat; Özpinar, Saliha; Öztaş, Dilek; Düz, Serkan; Cihaner, Perihan
The primary objective of this study is to examine the sociodemographic determinants influencing parents' administration of vitamin C to children participating in sports activities. The research was conducted with the participation of 697 parents residing in various districts of Istanbul and having children aged 9–18 years. Data were collected using a questionnaire and analysed using logistic regression, chi-square test, t-test, and multiple regression analyses in the SPSS 25 programme. The child's regular vitamin C use was considered the dependent variable. The parents' educational level, income level, occupational status, and family structure were evaluated as independent variables. When evaluating the findings, we observed that as the level of education increased, parental awareness became more pronounced. In particular, we found that the rate of regular vitamin C use was significantly higher among children of parents with high income levels, university degrees, and office jobs (p<0.05). Another finding wasthat individuals who exercised regularly were more aware. It was also determined that vitamin C use is more prevalent among children who engage in significantly more weekly exercise and are younger in age (p<0.001). In conclusion, parents' socioeconomic and educational levels play a decisive role in children's immune support behaviours. These findings have the potential to contribute to the development of parent-focused educational programmes and health policies aimed at supporting children's health.
Yeşil Büyüme Bağlamında Enerji ve Sağlık: BRICS Ülkeleri Örneği
(2025) Mutlu, Hatice; Ateş, Gözde Bozkurt; Türkoğlu, Mesut Can
Bu araştırma, BRICS (Brezilya, Rusya, Hindistan, Çin ve Güney Afrika) ülkelerinde yeşil büyüme, enerji kullanımı, yenilenebilir enerji arzı, sağlık göstergeleri ve kişi başına düşen gayrisafi yurtiçi hasıla (GSYİH) arasındaki ilişkileri incelemektedir. Araştırmada, zaman serisi verilerinde uzun dönem ilişkileri analiz eden Bootstrap Otoregresif Dağıtılmış Gecikme Modeli (ARDL) kullanılmıştır. 1990-2021 yılları arasını kapsayan araştırma verileri, Ekonomik İşbirliği ve Kalkınma Örgütü (OECD) veri havuzunda yer alan yeşil büyüme göstergelerinden elde edilmiştir. Bulgular, belirtilen yıllar arasında BRICS ülkelerinde farklı eşbütünleşme süreçleri bulunduğunu, ayrıca yenilenebilir enerji arzı ve kişi başına reel GSYİH ile doğumda beklenen yaşam süresi arasında eşbütünleşik bir ilişkinin var olduğunu göstermektedir. Granger nedensellik testi sonuçları, yenilenebilir enerji kullanımının doğumda beklenen yaşam süresini olumlu etkilediğini, enerji yoğunluğunun ise ekonomik büyüme üzerinde belirleyici bir faktör olduğunu ortaya koymuştur. Ancak, ekonomik büyüme bağımlı değişken olarak ele alındığında uzun dönemli eşbütünleşme tespit edilmemiştir. Sonuçlar, enerji tüketimi ve CO2 emisyonlarının kısa vadede ekonomik büyümenin önemli belirleyicileri olduğunu göstermektedir. Araştırma, sürdürülebilir ekonomik ve çevresel kalkınma stratejilerinin sağlık politikaları ile entegrasyonunun önemini vurgulamakta ve politika yapıcılara yenilenebilir enerji yatırımlarını artırmaya yönelik öneriler sunmaktadır.
