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Publication Open Access 25-hydroxyvitamin D levels are low but not associated with disease activity in chronic spontaneous urticaria and depression(AEPress, 2020) Vurgun, Eren; Güntaş, Gürkan; Kocatürk Göncü, Özgür Emek; Memet, Bachar; Doctor; School of Medicine; Koç University Hospital; 217219; N/AAim: to evaluate vitamin D levels in patients with chronic spontaneous urticaria (CSU), depression and both of them, thus to fi nd out whether vitamin D may be a common causative factor of CSU and depression. Methods: thirty patients with CSU, 30 patients with depression, 30 patients with both CSU and depression and 30 healthy volunteers as control group were involved in the study. Serum 25-hydroxyvitamin D (25(OH) D) levels of these groups were measured and compared. Correlations between 25(OH)D levels and the activity of CSU and depression were analyzed. Results: healthy controls' 25(OH)D levels (17.2±8.8 ng/mL) were higher than patients with CSU (9.1±5.1 ng/mL), depression (8.9±6.1 ng/mL) and CSU with depression (7.7±4.7 ng/mL) (p<0.001, p<0.001 and p<0.001, respectively). There were no differences in 25(OH)D levels between CSU patients with and without depression, between depression patients and CSU patients with and without depression (p=0.43, p=0.82 and p=0.92, respectively). There were no correlations between 25(OH)D levels and the activity of CSU or depression (p=0.99 and p=0.76, respectively). Conclusion: Lower 25(OH)D levels in CSU and/or depression may appear as a secondary phenomenon, which means being result of these diseases rather than the cause (Tab. 1, Fig. 2, Ref. 41).Publication Open Access 3D engineered neural co-culture model and neurovascular effects of marine fungi-derived citreohybridonol(American Institute of Physics (AIP) Publishing, 2022) Polat, İrem; Özkaya, Ferhat Can; El-Neketi, Mona; Ebrahim, Weaam; Şengül, Gülgün; Department of Mechanical Engineering; Sokullu, Emel; Sarabi, Misagh Rezapour; Taşoğlu, Savaş; Faculty Member; Faculty Member; Department of Mechanical Engineering; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); Koç Üniversitesi İş Bankası Yapay Zeka Uygulama ve Araştırma Merkezi (KUIS AI)/ Koç University İş Bank Artificial Intelligence Center (KUIS AI); KU Arçelik Research Center for Creative Industries (KUAR) / KU Arçelik Yaratıcı Endüstriler Uygulama ve Araştırma Merkezi (KUAR); School of Medicine; Graduate School of Sciences and Engineering; College of Engineering; 163024; N/A; 291971Marine-based biomolecules are emerging metabolites that have gained attention for developing novel biomaterials, drugs, and pharmaceutical in vitro platforms. Here, we developed a 3D engineered neural co-culture model via a 3D prototyped sliding frame-platform for multi-step UV lithography and investigated the neurovascular potential of citreohybridonol in neuroblastoma treatment. Citreohybridonol was isolated from a sponge-derived fungus Penicillium atrovenetum. The model was characterized by Fourier-transform infrared spectroscopy and scanning electron microscopy analysis. Human umbilical cord vein endothelial cells (HUVECs) and neuroblastoma (SH-SY5Y) cell lines were encapsulated in gelatin methacrylate (GelMA) with and without citreohybridonol. The effect of citreohybridonol on the proliferation capacity of cells was assessed via cell viability and immunostaining assays. GelMA and 3D culture characterization indicated that the cells were successfully encapsulated as axenic and mixed with/without citreohybridonol. The cytotoxic test confirmed that the 3D microenvironment was non-toxic for cultural experiments, and it showed the inhibitory effects of citreohybridonol on SH-SY5Y cells and induced the proliferation of HUVECs. Finally, immunohistochemical staining demonstrated that citreohybridonol suppressed SH-SY5Y cells and induced vascularization of HUVECs in mixed 3D cell culture.Publication Open Access A comparison of glycemic parameters and their relationship with C-peptide and Proinsulin levels during partial remission and non-remission periods in children with type 1 diabetes mellitus-a cross-sectional study(BioMed Central, 2021) Çakır, Esra Papatya; Yeşiltepe Mutlu, Rahime Gül; Çapacı, Merve; Can, Ecem; Gökçe, Tuğba; Bayrakçı, Gizem; Muradoğlu, Serra Küpçüoğlu; İncir, Said; Hatun, Şükrü; Faculty Member; Faculty Member; School of Medicine; Koç University Hospital; 153511; N/A; N/A; N/A; N/A; N/A; N/A; 153504Background: currently, there is a lack of data relating to glycemic parameters and their relationship with C-peptide (CP) and proinsulin (PI) during the partial remission period (PRP) in type 1 diabetes mellitus (T1D). The aim of this study was to evaluate glycemic parameters in children with T1D who are in the PRP using intermittently scanned continuous glucose monitoring systems (isCGMS) and to investigate any relationships between CP and PI levels. Methods: the study included 21 children who were in the PRP and 31 children who were not. A cross-sectional, non-randomized study was performed. Demographic, clinical data were collected and 2 week- isCGMS data were retrieved. Results: the Serum CP showed a positive correlation with time-in-range in the PRP (p:0.03), however PI showed no correlations with glycemic parameters in both periods. The Serum CP and PI levels and the PI:CP ratio were significantly higher in the PRP group than in the non-PRP group. In the non-PRP group, the PI level was below 0.1 pmol/L (which is the detectable limit) in only 2 of the 17 cases as compared with none in the PRP group. Similarly, only 2 of the 17 children in the non-PRP group had CP levels of less than 0.2 nmol / L, although both had detectable PI levels. Overall time-in-range (3. 9-1.0 mmol/L) was significantly high in the PRP group. In contrast, the mean sensor glucose levels, time spent in hyperglycemia, and coefficient of variation levels (32.2vs 40.5%) were significantly lower in the PRP group. Conclusions: although the mean glucose and time in range during the PRP was better than that in the non-PRP group, the glycemic variability during this period was not as low as expected. While the CP levels showed an association with TIR during the PRP, there was no correlation between PI levels and glycemic parameters. Further studies are needed to determine if PI might prove to be a useful parameter in clinical follow-up.Publication Open Access A new prognostic model for primary sclerosing cholangitis(Aves, 2019) Acar, Sencan; N/A; Akyıldız, Murat; Faculty Member; School of MedicinePublication Open Access A new risk-scoring system for colorectal cancer and polyp screening by Turkish Colorectal Cancer and Polyp Study Group(Aves, 2022) Erdem, L.; Akbal, E.; Koçak, E.; Tucer, D.; Üçbilek, E.; Uyanıkoğlu, A.; Dolapçıoğlu, C.; Şirin, G.; Alkım, H.; Soylu, A.; Doğanay, L.; Kürbüz, A.K.; Özdil, K.; Alagözlü, H.; Erürker Öztürk, T.; Sezikli, M.; Adalı, G.; Çoban, M.; Hülagü, S.; Değertekin, H.; Atasoy, A.; Akyüz, F.; Gaffarlı, İ.; Saruç, M.; Altıntaş, E.; Sezgin, O.; Tözün N.; Ahıshalı, Emel; School of MedicineBackground: colorectal cancer is one of the most commonly diagnosed types of cancer worldwide. An early diagnosis and detection of colon cancer and polyp can reduce mortality and morbidity from colorectal cancer. Even though there are a variety of options in screening tests, the question remains on which test is the most effective for the early detection of colorectal cancer. In this prospective study, we aimed to develop a simple, useful, effective, and reliable scoring system to detect colon polyp and colorectal cancer. Methods: we enrolled 6508 subjects over the age of 18 from 16 centers, with colonoscopy screening. The age, smoking status, alcohol consumption, body mass index, polyp incidence, polyp size, number and localization, and pathologic findings were recorded. Results: the age, male gender, obesity, smoking, and family history were found as independent risk factors for adenomatous polyp. We have developed a new scoring system which can be used for these factors. With a score of 4 or above, we found the following: sensitivity 81%, specificity 40%, positive predictive value 25.68%, and negative predictive value 89.84%, for adenomatous polyp detection; and sensitivity 96%, specificity 39%, positive predictive value 3.35%, negative predictive value 99.29%, for colorectal cancer detection. Conclusion: even though the first colorectal cancer screening worldwide is generally performed for individuals over 50 years of age, we recommend that screening for colorectal cancer might begin for those under 50 years of age as well. Individuals with a score ? 4 must be included in the screening tests for colorectal cancer.Publication Open Access A novel modular dynamic stabilization system for the treatment of degenerative spinal pathologies(Turkish Neurosurgical Society, 2019) Çevik, Orhun Mete; Erbulut, Deniz Ufuk; Goel, Vijay; N/A; Özer, Ali Fahir; Yaman, Onur; Şentürk, Salim; Öktenoğlu, Bekir Tunç; Sasani, Mehdi; Süzer, Süleyman Tuncer; Faculty Member; Doctor; Doctor; Faculty Member; School of Medicine; 1022; N/A; N/A; N/A; N/A; 221691Aim: to show the preliminary clinical results of the Orthrus modular dynamic stabilization system that is a new instrumentation system intended for degenerative diseases of the lumbar spine. Material and methods: the system utilizes two different types of screws that can be used in conjunction with different types of rods such as titanium, carbon fiber or PEEK. The first type of screw is a double headed screw to interconnect to the upper and lower level with independent rods. The second type of screw is a sliding screw to be used on a immovable vertebrae that allows movement in two planes on the tip. Results: the system has been used on 36 patients with pathology varying from degenerative disc disease to degenerative lumbar scoliosis. Satisfactory results have been obtained in a all 36 patients in the 12-month follow-up period. Conclusion: the Orthrus dynamic system shows better clinical results than the available dynamic systems on the market. It also proves to provide similar fusion with considerably less postoperative morbidity which makes it a better method to treat adult degenerative spine diseases for carefully chosen patients.Publication Open Access A practitioner’s guide to handling irregularities resulting from the 2014 revisions of the Turkish Household Labor Force Survey(Boğaziçi Üniversitesi İktisadi ve İdari Bilimler Fakültesi, 2021) Poyraz, Meltem; Department of Economics; Demirci, Murat; Faculty Member; Department of Economics; College of Administrative Sciences and Economics; 272082We document the implications of the 2014 revisions to the Turkish Household Labor Force Survey and offer guidance on how to handle the irregularities in population and unemployment statistics that resulted from two particular revisions. First, new population projections were adopted to assign survey weights. Second, a narrower definition of unemployment was adopted. We propose methods to adjust the survey weights for the pre-2014 period in order to discern changes in population statistics by age groups and regions without interruption over time and to calculate the unemployment rates according to both broader and narrower definitions since 2004. / Bu çalışmada TÜİK Hanehalkı İşgücü Anketi’ninde 2014 yılında yapılan düzenlemelerden kaynaklanan bazı sonuçları bulguluyor, nüfus ve işsizlik istatistiklerinde yapılan revizyonların özellikle ikisinden kaynaklanan sorunların nasıl ele alınması gerektiği hakkında yol gösteriyoruz. İlk revizyon, anket ağırlıklarının dayandırıldığı yeni nüfus projeksiyonlarının kabul edilmesidir. İkincisi ise, dar tanımlı bir işsizlik tanımına geçilmesidir. Bu çalışmada 2014 öncesindeki anket ağırlıklarını nüfus istatistiklerinde yaş bazında ve bölgesel olarak kopma olmayacak şekilde yeniden ayarlamak ve işsizlik oranlarını geniş ve dar tanımlı olarak 2004 yılından itibaren hesaplamak için yöntemler öneriyoruz.Publication Open Access A rare case of juvenile amyotrophic lateral sclerosis(Turkish National Pediatric Society, 2021) Bodur, Muhittin; Toker, Rabia Tütüncü; Okan, Mehmet Sait; Başak, Ayşe Nazlı; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; 1512Background: amyotrophic lateral sclerosis (ALS) is a chronic motor neuron disease characterised by progressive weakness in striated muscles resulting from the destruction of neuronal cells. The term juvenile ALS (JALS) is used for patients whose symptoms start before 25 years of age. JALS may be sporadic or familial. Case: here, we present a sporadic case of JALS because of its rarity in children. The heterozygous p.Pro525Leu (c.1574C>T) variation was identified in the fused in sarcoma (FUS) gene. Conclusion: the p.Pro525Leu mutation in the FUS gene has been detected in patients with ALS, characterised by early onset and a severely progressive course.Publication Open Access A rehabilitation protocol for patients with lumbar degenerative disc disease treated with posterior transpedicular dynamic stabilization(Turkish Neurosurgical Society, 2017) Ataker, Yaprak; Çerezci, Önder; Canbulat, Nazan; Öktenoğlu, Bekir Tunç; Sasani, Mehdi; Erçelen, Ömür; Süzer, Süleyman Tuncer; Özer, Ali Fahir; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Koç University Hospital; 58534; N/A; N/A; N/A; 221691; 1022AIM: To evaluate the efficacy of the rehabilitation protocol on patients with lumbar degenerative disc disease after posterior transpedicular dynamic stabilization (PTDS) surgery. MATERIAL and METHODS: Patients (n=50) with single level lumbar degenerative disc disease were recruited for this study. Patients had PTDS surgery with hinged screws. A rehabilitation program was applied for all patients. Phase 1 was the preoperative evaluation phase. Phase 2 (active rest phase) was the first 6 weeks after surgery. During phase 3 (minimal movement phase, 6-12 weeks) pelvic tilt exercises initiated. In phase 4 (dynamic phase, 3-6 months) dynamic lumbar stabilization exercises were started. Phase 5 (return to sports phase) began after the 6th month. The primary outcome criteria were the Visual Analogue Pain Score (VAS) and the Oswestry Disability Index (ODI). Patients were evaluated preoperatively, postoperative 3rd, 12th and 24th months. RESULTS: The mean preoperative VAS and ODI scores were 7.52±0.97 and 60.96±8.74, respectively. During the 3rd month, VAS and ODI scores decreased to 2.62±1.05 and 26.2±7.93, respectively. VAS and ODI scores continued to decrease during the 12th month after surgery to 1.4±0.81 and 13.72±6.68, respectively. At the last follow-up (mean 34.1 months) the VAS and ODI scores were found to be 0.68±0.62 and 7.88±3.32, respectively. (p=0.0001). CONCLUSION: The protocol was designed for a postoperative rehabilitation program after PTDS surgery for patients with lumbar degenerative disc disease. The good outcomes are the result of a combination of very careful and restrictive patient selection, surgical technique, and the presented rehabilitation program.Publication Open Access A single-center report of COVID-19 disease course and management in liver transplanted pediatric patients(Wiley, 2021) Yüksel, Muhammed; Aktürk, Hacer; Mızıkoğlu, Özlem; Toroslu, Ertuğ; Arıkan, Çiğdem; Researcher; Faculty Member; Researcher; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; Koç University Hospital; N/A; N/A; N/A; N/A; 240198Background: in 2019, SARS-CoV-2 causing COVID-19 emerged. Severe COVID-19 symptoms may evolve by virtue of hyperactivation of the immune system. Equally, immunocompromised patients may be at increased risk to develop COVID-19. However, treatment guidelines for children following liver transplantation are elusive. Methods: as a liver transplantation center, we diagnosed and followed up 10 children (male/female: 8/2) with a median age of 8.5 years (IQR: 5.2-11.0), with COVID-19 post-liver transplant between March 2019 and December 2020. COVID-19 diagnosis was based on PCR test and or florid X-ray findings compatible with COVID-19 in the absence of other cause. We retrospectively collected clinical and laboratory data from electronic patient records following written consent from patients/parents. Results: nine patients were diagnosed as definitive (PCR positive) with one patient being diagnosed as probable COVID-19. Seven patients recovered without any support whereas three were admitted for non-invasive oxygenation. Lymphopenia and/or high levels of serum IL-6 were detected in four patients. Six patients mounted anti-SARS-CoV-2 antibodies at median 30 days (IQR: 26.5-119.0) following COVID-19 diagnosis. Antibiotic therapy, favipiravir, anakinra, and IVIG were used as treatment in 4,1,1 and 2 patients, respectively. Furthermore, we kept the tacrolimus with or without everolimus but stopped MMF in 2 patients. Importantly, liver allograft function was retained in all patients. Conclusions: we found that being immunocompromised did not affect disease severity nor survival. Stopping MMF yet continuing with tacrolimus was an apt treatment modality in these patients.