İstanbul Sağlık ve Teknoloji Üniversitesi Kurumsal Akademik Arşivi
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Long-term outcomes of extended versus segmental resection for transverse colon cancer: A population-based analysis based on the SEER database
No full textObjective: To investigate long-term cancer-specific outcomes associated with extended versus segmental colectomy (SC) in patients with stage I-III transverse colon adenocarcinoma using a large, population-based cohort. Material and Methods: Patients who diagnosed with transverse colon cancer undergoing curative-intent colectomy were identified from the surveillance, epidemiology, and end results database (2013-2019). Surgical procedures were categorized as extended colectomy (EC) or SC based on standardized procedural coding. 1:1 propensity score matching was performed to reduce selection bias and balance baseline characteristics. Cancer-specific survival (CSS) was analyzed using multivariable Cox proportional hazards regression. Results: Among 18,799 eligible patients, 58% underwent EC. EC was more frequently performed in individuals with higher tumor stage (p12 lymph nodes retrieved: 94% vs. 89%, p<0.01). Five-year overall survival did not differ significantly between groups (65.6% for EC vs. 66.9% for SC, p=0.074). However, SC was associated with a modest but statistically significant improvement in CSS (84.3% vs. 81.7%, p<0.01). In adjusted analysis, surgical extent (HR=0.8376, p<0.001), along with age, sex, tumor grade, stage, and lymph node yield, were independently associated with CSS. Conclusion: While EC is more commonly utilized in advanced-stage disease and facilitates higher lymph node retrieval, SC offers comparable—and potentially superior—CSS in selected patients. These findings support the consideration of a tailored surgical strategy based on tumor biology and individual patient characteristics
Integrated use of finite element analysis and gaussian process regression in the structural analysis of AISI 316 stainless steel chimney systems
No full textThis study aimed to conduct a comprehensive structural analysis and machine learning-assisted predictive modelling of a chimney system manufactured from 2 mm thick AISI 316 stainless steel with a diameter of Ø500 mm. The primary motivation of this work was to examine, in detail, the structural behavior of chimney modules under various force and pressure conditions using conventional methods, and to develop a reliable model capable of performing parametric predictions for new scenarios based on the acquired data. The scope of the study encompassed finite element analyses of both the entire chimney system and 3-meter-long intermediate modules, field tests, and the application of the Gaussian Process Regression (GPR) machine learning model. In the analysis of the entire chimney system under an applied force of 22,000 N, a maximum stress of 28 MPa and a safety factor of 8.39 were observed in the chimney clamps. The total deformation was found to be 0.58 mm, which is within acceptable limits. In the structural analysis of the intermediate chimney modules under a force of 1000 N and an internal pressure of 5 MPa, a maximum stress of 11,984 MPa, a safety factor of 1.71, and a total deformation of 0.46 mm were determined, all of which are consistent with the literature. The accuracy of these analyses was validated through pressure and leakage tests conducted in accordance with the EN 1859 standard. The developed GPR machine learning model demonstrated exceptionally high accuracy (R² > 0.999) in predicting Von Mises stress values, providing reliable forecasts with an error rate of less than 3% when compared to ANSYS simulation outputs. However, in predicting total deformation values, error rates exceeded 70%, indicating that the model was less sensitive in low-amplitude deformation cases. These findings suggest that the GPR model can generate reliable predictions for Von Mises stress a more critical parameter than total deformation in chimney design. By integrating conventional structural analysis methods with advanced machine learning techniques, this study demonstrates the potential of predictive modeling as an efficient and reliable tool in engineering design processes, making a significant contribution to the field’s body of knowledge
Çobanoğlu çekme helva işletmesi
No full textÇobanoğlu Çekme Helva işletmesi, Kastamonu'nun geleneksel gıda üretiminde öne çıkan örneklerinden biridir. 1994 yılında Coşkun Çobanoğlu tarafından kurulan işletme, başlangıçta küçük ölçekli bir üretim tesisi olarak faaliyet göstermiştir. Kuruluş sürecinde sınırlı sermaye ve yoğun emek gücü ile üretim yapılırken, zamanla teknolojik gelişmelerin de etkisiyle makineleşmeye geçilmiştir. İşletme sahibi, görüşme sırasında özellikle 1994 sonrasında üretimde modern makinelerin kullanılmaya başlandığını ve bugün üretimin yaklaşık %60'ının makine destekli gerçekleştiğini, geri kalanının ise geleneksel yöntemlerle sürdürüldüğünü ifade etmiştir. Bu durum, işletmenin hem modern üretim kapasitesine ulaşmasını hem de geleneksel tat ve kalitenin korunmasını sağlamaktadır
Tailoring natural solvents: Deep eutectic approach for recovering bioactives from Prunus Spinosa L.
No full textIn this study, several choline chloride (ChCl)-based deep eutectic solvent (DES) combinations were prepared at different molarratios (1/1, 1/2, and 2/1) using amine (urea), polyols (ethylene glycol and glycerol), and carboxylic acids (lactic acid, formic acid,propionic acid, and acetic acid). The performances of the DESs in the homogeniser-assisted extraction of Prunus spinosa L.fresh fruit were compared depending on the total phenolic content (TPC), total anthocyanin content (TAC), and 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity (antioxidant activity [AA]) yields. Based on the findings of Tukey’s test formultiple comparisons, ChCl/formic acid (2/1) provided the best extraction efficiency with statistically significant differences(p < 0.05). Fourier-transform infrared spectroscopy was used to confirm the formation of the proposed DES. Furthermore, theproposed DES also showed better performance compared to conventional aqueous ethanol (60%, v/v) and water. Then, theselected DES (ChCl/formic acid, 2/1) was employed for the optimization study using the Box-Behnken Design of the responsesurface methodology. The optimum process conditions for the maximum yields of TPC (52.34 mg-GAE/g-FF), TAC (2.09 mg-cyn-3-glu/g-FF), and AA (89.21%) were found to be 50% (v/v) water in the DES, 0.833 g of material, and 69.906 s extractiontime
Investigation of the effects of different finishing and polishing systems on the ion release and surface roughness of bioactive restorative materials
No full textBu çalışma, dört farklı bitirme ve cilalama sisteminin sekiz farklı restoratif materyal üzerindeki flor ve kalsiyum iyon salınımı ile yüzey pürüzlülüğü üzerine etkilerini karşılaştırmalı olarak değerlendirmek amacıyla gerçekleştirilmiştir. Her restoratif materyal grubu, uygulanacak bitirme-cilalama sistemine göre beş alt gruba ayrılmıştır (n=10/grup). Başlangıç ve 28. gün yüzey pürüzlülüğü ölçümleri mekanik profilometre ile, flor ve kalsiyum salınım düzeyleri ise 1., 2., 7., 14. ve 28. günlerde iyon-selektif elektrot (ISE) yöntemiyle değerlendirilmiştir. Ardından materyaller 5000 devirlik termal siklusa (TSS) tabi tutulmuş ve son flor, kalsiyum salınımı ile yüzey pürüzlülük değerleri ölçülmüştür. Verilerin istastistiksel incelenmesinde Kolmogorov-Smirnov testi, Levene testi, Wilcoxon İşaret testi, Friedman testi, Dunn-Bonferroni çoklu karşılaştırma testi, Kruskal Wallis testi kullanılmıştır. p0,00625; p>0,010). Ancak bazı kombinasyonlarda belirgin farklar kaydedilmiştir. Buna göre, 1. gün ölçümlerinde Beautifil II hariç tüm materyallerde Ecocomp sistemi, Mylar bant grubuna göre daha yüksek pürüzlülük üretmiştir (p0.00625, p>0.010). However, notable differences were recorded in some combinations. According to the day 1 measurements, the Ecocomp system produced higher roughness than the Mylar strip group in all materials except Beautifil II (p<0.00208). In the day 28 and post-TC measurements, the Ecocomp system was also observed to create higher surface roughness values, particularly in materials like Activa, Cention N, Beautifil II, and Fuji IX (p<0.00208). Similarly, some groups with the Diacomp Plus system also exhibited high roughness. Finally, when the relationship between the time-dependent changes in fluoride and calcium release and the surface roughness levels was examined, no statistically significant correlation was found. This finding suggests that ion release and surface characteristics may change independently of each other. This study revealed that different finishing and polishing systems have significant effects on the fluoride and calcium ion release as well as the surface roughness of restorative materials; however, no statistically significant correlation was found between these two parameters
Çocuk hastada kompound odontomanın konservatif tedavisi: Bir olgu sunumu
No full textGiriş ve Amaç: Odontomalar, morfolojik olarak normal hücreler içermekle birlikte yapısal organizasyonları kusurlu olan odontojenik lezyonlar olarak kabul edilirler (1) . Mine, dentin, sement ve pulpa gibi odontojenik yapılardan oluşan, yüksek derecede farklılaşma gösteren, genellikle asemptomatik ilerleyen benign tümörlerdir (2). Yavaş ve ağrısız büyümeleriyle tanımlanan odontomalar, bazı durumlarda diş sürmesinde gecikme, dişlerin gömülü kalması, ilgili bölgede ağrı, kemikte ekspansiyon ve kök rezorbsiyonu gibi belirtilere yol açabilirler (3). Odontomaların tedavisi cerrahi eksizyondur. Kistik dejenerasyon potansiyeli nedeniyle odontomanın etrafındaki yumuşak doku ile birlikte eksizyonu önerilen tedavi şeklidir (4). Bu olgu raporunda sağ maksiller bölgede gelişmiş olan kompound odontoma tanısı alan 7 yaşındaki hastanın klinik ve radyografik bulguları sunulmuştur. Olgu: 7 yaşındaki hasta sağ maksiller kanin-premolar bölgesinde 1 senedir mevcut olan ağrısız, fikse bir şişlik ve 54 - 55 numaralı dişlerin mobilitesi şikayetiyle kliniğimize başvurmuştur. Aldığımız anamnez doğrultusunda sistemik hastalığı bulunmayan hastanın 53 numaralı dişinin 2 ay önce kendiliğinden eksfoliye olduğu bilgisi edinilmiştir. İntraoral muayenede bölgeyi içine alan abse,fistül veya çürük tespit edilmemiştir. Yapılan radyografik muayenede ilgili bölgede çok sayıda radyoopak diş benzeri yapının mevcudiyeti dikkat çekmiştir. Çevre dokularla ilişkisini görmek ve tanımızı desteklemek amacıyla konik ışınlı bilgisayarlı tomografi görüntüsü alınmıştır. Kompound odontoma ön tanısı ile hastanın sağ maksiller kanin-premolar bölgesindeki diş benzeri yapılar lokal anestezi altında eksize edilmiştir. Mobilitesi olan 54 ve 55 numaralı dişlerin çekimi yapılmıştır. Histopatolojik inceleme ile eksize edilen dokunun kompound odontoma olduğunu doğrulanmıştır. 1 hafta sonraki kontrolde ilgili bölgedeki intraoral şişliğin iyileştiği gözlenmiştir. Yer kaybını önlemek amacıyla üst çeneye Nance apareyi yapılmış ve dişlerin fizyolojik sürmesi takip edilmiştir. Sonuç: Kompound odontomanın enükleasyon yöntemiyle tedavisinin ardından semptomlar ortadan kalkmıştır. Daimi dentisyona geçişteki boşluğu idame ettirebilmek amacıyla Nance apareyi uygulanmış, dişlerin fizyolojik sürmesi devam etmiştir. Böylece erken yaşta tanı ve tedavisinin yapılması ile gelişmekte olan oklüzyon üzerine herhangi bir zararlı etki oluşmaksızın tüm dişlerin normal pozisyonlarını almaları sağlanabilecektir. Karışık dişlenme döneminde yapılacak ayrıntılı dental muayene daimi dişlenmeye sağlıklı bir geçişin sağlanmasında büyük yararlar sağlayacaktır
Examination of anatomical features of zygomaticofacial foramen in children: A 3d reconstruction study
No full textBackground Considering the implications of surgical fixation techniques such as plating, screwing, or wiring in pediatric zygomatic fractures, a detailed understanding of the zygomaticofacial foramen (ZFF) anatomy in children may help reduce intraoperative complications particularly injury to the zygomaticofacial nerve, which passes through the ZFF. Objective The aim of the present study is to examine the morphometric and morphological features of the ZFF in the pediatric population. Methods Before the study commenced, approval was obtained from Gaziantep University Clinical Research Ethics Committee (Approval number: 2024/177). Cone-beam computed tomography (CBCT) images of 119 patients who applied to Gaziantep University Faculty of Dentistry, Department of Oral and Maxillofacial Radiology for any reason were retrospectively examined with Radiant DICOM Viewer program. The presence, number, localization and distances to certain anatomical points of ZFF were measured. The ZFF was classified based on the number of foramina. To determine the localization of the foramen, the lateral surface of zygomatic bone was divided into four quadrants using two reference lines. These quadrants were designated as a, b, c, and d in a clockwise direction from the inferomedial to the superomedial region. Statistical analyses were performed with SPSS 24.0 package program and p < 0.05 was considered statistically significant. Results A total of 119 children (male: 65, female: 54; mean age: 13.14 ± 3.24) CBCT images (238 sides) were examined. In the classification based on the number of foramina, the absence of any foramen was defined as Type 0 (106, 44.5%); the presence of one, two, and three foramina was classified as Type I (91, 38.2%), Type II (35, 14.7%), and Type III (6, 2.5%), respectively. The mean distance between ZFF-orbit and ZFF-temporozygomatic suture was greater in male than in female (p = 0.006, p = 0.009, respectively). The mean distance between ZFF-frontozygomatic suture was greater in female (p = 0.032). The distances between ZFF-zygomaticomaxillary suture and lowest point of zygomatic bone were significantly different between age groups (p = 0.026, p = 0.004, respectively). Conclusion The findings of the present study indicate that the zygomaticofacial foramen (ZFF) is most frequently located in region c and rarely in region b. Based on this observation, region b may represent a safer zone for surgical interventions in this area. The findings of the present study may help to minimize complications in surgeries and invasive procedures involving the zygoma region in children
Dermoscopy-guided surveillance in xeroderma pigmentosum: A retrospective analysis
No full textAim: Xeroderma pigmentosum (XP) is a life-threatening disease characterized by high rates of skin cancers. Therefore, it is important to establish key guidelines for the follow-up of these patients to detect skin cancers, particularly melanoma, at an early stage. Materials and Methods: This is a retrospective study that includes the analysis of the follow-up findings and medical records of XP patients who were followed up with whole-body skin examination, dermoscopic examination, and whole-body photographing between 2003 and 2021 in the Dermato Oncology unit of Ege University Department of Dermatology. Results: Of the 19 patients, 10 were male and 9 were female. The youngest patient was 5 years old, while the oldest patient was 64 years old. A total of 234 lesions were excised from these patients. Seventeen melanomas were excised, including 11 in situ, with a Breslow thickness of less than 1 mm. The highest Breslow scores belong to patients who missed their appointments or did not receive follow-up care previously. Conclusion: It was observed that regular full-body skin examinations, whole-body photography, and dermoscopic monitoring performed at 3-month intervals in XP patients are helpful in detecting skin malignancies at an early stage and preventing unnecessary excisions
Determination of oxidant and antioxidant status in the saliva of mouth-breathing children
No full textSüperoksit dismutaz (SOD), Katalaz (CAT) ve Malondialdehit (MDA), tükürükte ölçülebilen biyokimyasal belirteçler olup; oral ve sistemik oksidatif dengeyi değerlendirmede önemli göstergeler olarak kabul edilmektedir. Bu çalışmanın amacı, ağız solunumu yapan çocukların tükürüklerindeki oksidatif stres göstergelerini değerlendirmektir. Bu doğrultuda lipid peroksidasyonu ürünü olan Malondialdehit ile temel antioksidan enzimler olan Süperoksit Dismutaz ve Katalaz düzeyleri tükürükte karşılaştırmalı olarak incelenmiştir. Çalışma İstanbul Sağlık ve Teknoloji Üniversitesi Diş Hekimliği Fakültesi Pedodonti Anabilim Dalı Kliniği'ne başvuran, 6-12 yaş aralığında, koopere ve herhangi bir sistemik hastalığı bulunmayan çocuklar üzerinde yapılmıştır. Kliniğe çalışmadan bağımsız nedenlerle başvuru yapan ve araştırmaya dahil edilme kriterlerini sağlayan hastalara, klinik muayene ve solunum değerlendirme testleri uygulanarak, ağız veya burun solunumu yapan hasta grupları oluşturulmuştur. Ardından tükürük numunelerinin alınması için hastalara ikinci bir randevu verilmiştir. Bu ziyarette, her katılımcıdan sabah saatlerinde pasif yöntem kullanılarak 3 mL uyarılmamış tam tükürük örneği toplanmış ve −20 °C'de saklanmıştır. Soğuk zincir ile laboratuvara iletilen numuneler +4 derece buzdolabında çözdürülerek deney aşamasına geçilmiştir. Bu çalışmada, antioksidan savunma enzimleri olarak SOD, CAT ve oksidatif stres belirteci olarak MDA düzeyleri, NBT ve TBARS esaslı spektrofotometrik yöntemler kullanılarak analiz edilmiştir. Ağız solunumu yapan çocukların tükürüklerinde MDA düzeylerinin burun solunumu yapanlara kıyasla belirgin şekilde yüksek olduğunu tespit edilmiştir. Buna karşılık ağız solunumu grubunda SOD ve CAT aktivitelerinin kontrol grubuna göre anlamlı derecede düşük olduğu belirlenmiştir. Yapılan regresyon analizleri, solunum paterninin oksidatif stres parametreleri üzerinde yaş ve cinsiyetten bağımsız olarak anlamlı bir belirleyici faktör olduğu göstermektedir. Bu çalışma, çocuklarda ağız solunumunun, yaş ve cinsiyetten bağımsız olarak tükürükte artmış oksidatif stres ve azalmış antioksidan aktivite ile ilişkili olduğunu ortaya koymuştur.Superoxide dismutase (SOD), Catalase (CAT), and Malondialdehyde (MDA) are biochemical markers that can be measured in saliva and are considered important indicators for assessing oral and systemic oxidative balance. This study aimed to enroll children aged 6–12 years who exhibited mouth breathing and presented to the Clinic of the Department of Pediatric Dentistry, Faculty of Dentistry, Istanbul Health and Technology University. The objective was to evaluate salivary oxidative stress indicators in children with mouth breathing. Accordingly, salivary levels of malondialdehyde, a lipid peroxidation product, together with the activities of key antioxidant enzymes superoxide dismutase and catalase were assessed. The study was conducted on cooperative children aged 6–12 years without systemic disease who presented to the clinic. Patients who presented to the clinic for reasons unrelated to the study but met the inclusion criteria were subjected to clinical examination and respiratory assessment tests, after which they were categorized into mouth-breathing or nasal-breathing groups. Participants were then given a second appointment for saliva collection. At this visit, 3 mL of unstimulated whole saliva was collected from each participant in the morning using the passive method and stored at −20 °C.Upon arrival, the samples were thawed at +4 °C and processed for analysis. In this study, SOD activity and MDA levels were analyzed using NBT- and TBARS-based spectrophotometric assays, respectively and CAT activity was determined by a spectrophotometric method. The findings showed that salivary MDA levels were significantly higher in children with mouth breathing than in those with nasal breathing. Conversely, SOD and CAT activities were significantly lower in the mouth-breathing group than in the control group. This study revealed that mouth breathing in children is associated with increased oxidative stress and decreased antioxidant activity in saliva, independent of age and sex
More than one century: Intravenous procaine therapy - A systematic review
No full textProcaine, traditionally introduced as a local anaesthetic, has revealed over more than a century a broad spectrum of systemic, pleiotropic pharmacological properties that far exceed its classical use. More than thirty distinct biological mechanisms have now been identified, including anti-inflammatory, vasodilatory, sympatholytic, membrane-stabilising, neuromodulatory, geroprotective, and epigenetically active effects. These actions provide the scientific foundation for its expanding clinical relevance in pain medicine, neuro-regulation, cardiovascular modulation, immune-related and degenerative disorders, and complementary oncology. Within Neural Therapy, Procaine occupies a central and irreplaceable role: its segmental, interference-field–oriented and autonomic-regulatory actions uniquely position it as the primary agent capable of restoring disturbed vegetative patterns, resolving chronic dysfunctions, and re-establishing physiological self-regulation. Beyond its local anaesthetic function, intravenous Procaine—especially in combination with bicarbonate—demonstrates profound regulatory effects on microcirculation, autonomic balance, inflammatory cascades, and mitochondrial and cellular resilience. The so-called “Procaine reset” reflects its capacity to transiently interrupt maladaptive neural patterns, modulate limbic activation, influence neurotransmitter systems, and restore homeostatic regulatory loops. The addition of bicarbonate prolongs Procaine’s plasma availability, enhances its intracellular penetration, and amplifies its eutrophic and anti-inflammatory properties. Although Procaine remains the primary therapeutic molecule in Neural Therapy, Lidocaine has also been utilised in selected clinical contexts. Lidocaine shares certain membrane-stabilising and anti-inflammatory features; however, its pharmacodynamics, autonomic influence, and regulatory depth are comparatively limited. Thus, Lidocaine may complement specific applications but cannot replace the superior vegetative-regulatory potential documented for Procaine. Procaine-Base infusion, when properly adapted to the patient's acid–base balance, represents a cornerstone therapy in regenerative medicine, improving pain thresholds, vascular perfusion, lymphatic drainage, and emotional equilibrium. Its safety profile—documented in hundreds of thousands of applications—is exceptionally favourable, with adverse effects being rare, transient, and mild. Given rising global burdens of chronic inflammatory, neurodegenerative, cardiovascular, metabolic, and oncologic disorders, Procaine emerges as a valuable multi-target regulatory agent capable of reducing symptom burden, complementing multimodal therapeutic strategies, and potentially lowering long-term health-care costs. Future high quality, large-scale studies are warranted to validate its systemic mechanisms, clarify dose–response relationships, and further integrate Procaine-based therapies into modern evidence-based frameworks