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
Association of body mass index with orbital fat volume in lower eyelid blepharoplasty
(Springer Nature, 2025) Solmaz, İskender Alkın; Ertan, Elif
Purpose To investigate the relationship between body mass index (BMI) and the volume of orbital fat excised during lower eyelid blepharoplasty. Methods This retrospective cross-sectional study included 58 patients who underwent bilateral transconjunctival lower eyelid blepharoplasty between January and December 2024. Total orbital fat volume was measured intraoperatively using a graduated cylinder. BMI was calculated from preoperative height and weight and classified according to World Health Organization criteria. Statistical analyses included Pearson correlation, one-way ANOVA with Tukey’s post-hoc test, and univariate and multivariable linear regression. Results The mean age of the patients was 49.2±11.6 years, and the mean BMI was 24.5±3.8 kg/m². The mean total orbital fat volume excised was 2.08 ± 0.94 cc. Fat volume differed significantly across BMI categories (p<0.001), with obese and overweight patients having greater excised fat than normal-weight individuals. Pearson correlation demonstrated a strong positive association between BMI and fat volume (r=0.592, p<0.001). In regression analysis, BMI was the only significant predictor of orbital fat volume, explaining 35.1% of the variance (R²=0.351). Conclusion BMI is strongly associated with orbital fat volume excised during lower eyelid blepharoplasty. These findings suggest that systemic adiposity extends to the periorbital region and highlight the relevance of considering BMI in preoperative planning to optimize surgical outcomes.
Limitations of MRI in differentiating solid and cystic components of craniopharyngiomas
(Springer Nature Link, 2025) Karaalioğlu, Banu; Çakıcı Öksüz, Nazlı; İpek, Veyselkarani; Çakır, Aslı; Kahraman, Osman; Özbek, Muhammet Arif
Purpose Craniopharyngiomas (CP) present with both solid and cystic structures in magnetic resonance imaging (MRI) stud ies. Contrary to MRI appearance, components described as cysts are not infrequently found as non-fluent structures during surgery. This study aims to address the discrepancy between radiology and surgery regarding the nature of these lesions and to evaluate them for their preoperative predictability. Materials and methods Preoperative MRI images of 24 CP patients were analyzed. The cystic components of the tumors were assessed in terms of quantitative and qualitative signal properties and contrast enhancement on conventional pulse sequences, and analyzed based on their macroscopic appearances. Results Thirteen of 31 lesions (42%) that suggested cyst on MRI were solid during surgery, with none showing contrast uptake. MRI demonstrated 100% sensitivity and negative predictive value (NPV), 71.7% specificity, and 58% positive pre dictive value (PPV) in identifying true cysts. Most lesions resembling cysts were hyperintense on FLAIR and T1WI and isointense on ADC maps, suggesting high protein content. However, surgically confirmed fluid-filled cysts exhibited similar signal characteristics in a comparable proportion. The only significant imaging indicator was a hypointense appearance on T2WI, with a mean intensity ratio close to that of the basal ganglia. Conclusion Accurate identification of solid and cystic components in craniopharyngiomas is critical for effective treatment planning. Although MRI is traditionally considered reliable for this purpose, 42% of lesions that appeared cystic without contrast enhancement were ultimately confirmed as non-fluid or solid during surgery. This study was unable to establish definitive MRI characteristics to reliably differentiate between cystic and solid components. Further research with larger cohorts is warranted to validate potential imaging markers and improve diagnostic accuracy.
Investigation of the association between nitric oxide synthase gene variants and NAFLD in adolescents with obesity
(De Gruyter, 2025) Hasanoğlu Sayın, Sevde; Kandemir, İbrahim; Oyacı, Yasemin; Khudiyeva, Shahri; Şahin, Memduh; Yetim Şahin, Aylin; Pehlivan, Sacide
Objectives: The present study aimed to investigate whether nitric oxide synthase (NOS) enzyme gene variants (iNOS rs1060826, eNOS rs1799983, eNOS 27-bp VNTR) play a role in the etiopathogenesis of nonalcoholic fatty liver (NAFLD) in adolescents. Methods: This cross-sectional study was conducted with obese adolescents [body mass index (BMI) standard devia tion score (SDS) ≥2] aged 10–19 years (104 individuals) and age- and sex-matched healthy individuals (64 individuals) whose presence of NAFLD was determined by ultrasound. The iNOS rs1060826 and eNOS rs1799983 variants were performed by Polymerase Chain Reaction-Restriction Frag ment Length Polymorphism (PCR-RFLP) method, and the eNOS 27-bp VNTR variant was analyzed using the PCR method. The genotypes detected were compared between the patient group and the healthy controls and with the clinical parameters of the patients. Results: iNOS rs1060826 and eNOS rs1799983 were inde pendent of obesity, whereas eNOS 27-bp VNTR was inde pendent of NAFLD. However, in the obese group, especially in those with NAFLD (+), the iNOS rs1060826 GG genotype was found to be associated with lower diastolic blood pres sure (DBP) (p=0.011). Compared with the clinical parameters, insulin resistance (HOMA-IR) was higher in those carrying the eNOS rs1799983 gene variant-TT genotype in the NAFLD (+) group (p=0.051). Conclusions: While the three functional gene variants of the NOS enzyme did not show a significant difference in terms of genotype between patients and healthy controls, it was determined that both the iNOS rs1060826 gene variant GG allele was associated with low DBP and HOMA-IR may be higher in those carrying the eNOS rs1799983 gene variant TT genotype in NAFLD (+) patients. The iNOS rs1060826 poly morphism is a potentially important genetic variant that may influence DBP regulation through its effects on nitric oxide production.
Aloe vera ve ayva çekirdeği müsilajı içeren aljinat türevli biyobozunur filmlerin üretimi ve karakterizasyonu
(Çanakkale Onsekiz Mart Üniversitesi, 2025) Keke, Zeynep Serra; Temizkan Özdamar, Kevser
Bu çalışma, biyobozunur ve fonksiyonel film üretimi amacıyla ayva çekirdeği musilajı ve aloe vera jeli içeren sodyum aljinat bazlı biyopolimer filmlerin sentezini ve karakterizasyonunu kapsamaktadır. Ayva çekirdeği, yüksek viskozite sağlayan doğal polisakkarit içeriği ile film matrisine mukavemet kazandırırken, aloe vera jeli antimikrobiyal ve antioksidan özellikleriyle biyolojik aktiviteyi güçlendirmektedir [1, 2]. Sodyum aljinat, biyouyumluluk ve film oluşturma kabiliyeti yüksek bir hidrojel olması nedeniyle temel taşıyıcı polimer olarak seçilmiştir [3]. Bu çalışma kapsamında, dört farklı hidrojel film formülasyonu hazırlanmıştır. Her bir formülasyon, sodyum aljinat, aloe vera, ayva çekirdeği, selüloz hidroksi etil selüloz (HEC) ve gliserol bileşenlerinin belirli oranlarda karıştırılmasıyla oluşturulmuştur. Film yapısında bulunan bileşenlerin birbirleriyle olan kimyasal ve fiziksel etkileşimleri, malzemenin mekanik ve fonksiyonel özelliklerini belirlemektedir. Film üretiminde solvent dökme yöntemi uygulanmış ve karakterizasyon aşamasında mekanik dayanım, su buharı geçirgenliği, biyobozunurluk ve antibakteriyel aktivite parametreleri değerlendirilmiştir. Fourier Dönüşümlü Kızılötesi Spektroskopisi (FTIR), UV-Vis Spektroskopisi ve Termogravimetrik Analiz (TGA) ile kimyasal yapı ve termal stabilite analizleri gerçekleştirilmiştir. Biyobozunurluk testleri, filmlerin çevresel koşullarda zamanla parçalanabilir olduğunu gösterirken, antibakteriyel testler inhibisyon etkisini doğrulamıştır. Elde edilen sonuçlar, ayva çekirdeği ve aloe vera içeren biyopolimer filmlerin sürdürülebilir ve çevre dostu bir alternatif sunduğunu göstermektedir. Bu bulgular, organik çözücü ve yüksek sıcaklık kullanmaksızın, biyobozunur malzemeler üzerine yapılan araştırmalara katkı sağlaması hedeflenmektedir.
A randomised clinical trial to evaluate a digital therapeutic (TH-001) for improving glycaemic control in adults with prediabetes
(SAGE Publications, 2025) Çakmak, Ramazan; Tosun, İlker; Avcu, Hasan; Birer, Gürkan Caner; Akgül, Özer; Saini, Kamal S.; Carnell, Jonathan; Kutlu, Orkide
Background and Aims: Prediabetes, characterized by elevated blood glucose levels below diabetes diagnostic thresh olds, presents a significant global health challenge due to high prevalence and associated risks for developing type 2 dia betes. Traditional diabetes prevention programs (DPPs) often face challenges in scalability and accessibility, particularly in underserved communities. Digital therapeutics (DTx), like TH-001, offer potential scalable solutions requiring clinical val idation. This randomized, open-label, controlled, parallel-group clinical trial aimed to evaluate the efficacy and safety of TH-001, a digital therapeutic application, reducing hemoglobin A1c (HbA1c) among adults with prediabetes over a 90-day intervention period. Methods: 68 eligible adults were randomly assigned to either standard care alone or standard care plus the TH-001 intervention. Primary outcomes measured were glycaemic parameters including HbA1c, fasting glucose, 2-h post-load glucose from an oral glucose tolerance test, and insulin levels, while secondary outcomes included anthropometric mea sures. User engagement metrics were also assessed. Results: The intervention significantly reduced HbA1c levels (mean difference −0.22%, p = .023) and body weight (−2.53 kg, p < .001) compared to the control group. Although fasting glucose and insulin levels showed positive trends, differences were not statistically significant. User engagement was high, correlating strongly with HbA1c reduction (r = .95, p < .001), demonstrating the critical role of sustained interaction with TH-001. Conclusions: TH-001 demonstrates significant effectiveness in HbA1c reduction and body weight, with strong user engagement suggesting it may effectively overcome traditional barriers of DPPs. Long-term studies are needed to confirm sustained benefits.
