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Publication Open Access Recommendations for clinical decision-making in children with type 1 diabetes and celiac disease: type 1 diabetes and celiac disease joint working group report(Galenos Yayınevi, 2022) Dalgıç, B.; Gökşen, D.; Aydoğdu, S.; Savaş, Erdeve Ş.; Kuloğu, Z.; Doğan, Y.; Aycan, Z.; Keser, A.; Beşer, Ö.F.; Özbek, M.N.; Bideci, A.; Ertem, D.; Evliyaoğlu, O.; Eliüz Tipici, B.; Gökçe, T.; Muradoğlu, S.; Koca, T.; Tütüncüler, F.; Baş, F.; Darendeliler, F.; Selimoğlu, M.A.; Hatun, Şükrü; Yeşiltepe Mutlu, Rahime Gül; Kızılkan, Nuray Uslu; Taşkın, Orhun Çığ; Faculty Member; Faculty Member; Faculty Member; School of Medicine; Koç University Hospital; 153504; 153511; 221274; 166686It is well-known that in children with type 1 diabetes (T1D), the frequency of Celiac disease (CD) is increased due to mechanisms which are not fully elucidated but include autoimmune injury as well as shared genetic predisposition. Although histopathologic examination is the gold standard for diagnosis, avoiding unnecessary endoscopy is crucial. Therefore, for both clinicians and patients’ families, the diagnosis of CD remains challenging. In light of this, a joint working group, the Type 1 Diabetes and Celiac Disease Joint Working Group, was convened, with the aim of reporting institutional data and reviewing current international guidelines, in order to provide a framework for clinicians. Several controversial issues were discussed: For CD screening in children with T1D, regardless of age, it is recommended to measure tissue transglutaminase-immunoglobulin A (tTG-IgA) and/or endomysial-IgA antibody due to their high sensitivity and specificity. However, the decision-making process based on tTG-IgA titer in children with T1D is still debated, since tTG-IgA titers may fluctuate in children with T1D. Moreover, seronegativity may occur spontaneously. The authors’ own data showed that most of the cases who have biopsy-proven CD had tTG-IgA levels 7-10 times above the upper limit. The decision for endoscopy based solely on tTG-IgA levels should be avoided, except in cases where tTG-IgA levels are seven times and above the upper limit. A closer collaboration should be built between divisions of pediatric endocrinology and gastroenterology in terms of screening, diagnosis and follow-up of children with T1D and suspicious CD.Publication Open Access Quadrant and dermatomal analysis of sensorial block in ultrasound-guided erector spinae plane block(Aves, 2022) Selvi, Onur; Tulgar, Serkan; Şerifsoy, Talat Ercan; Lance, Robert; Thomas, David Terence; Gürkan, Yavuz; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; 154129Objective: as a novel procedure now gaining popularity, erector spinae plane block has been the subject of many studies. However, dermatomal coverage of the sensory block caused by erector spinae plane block has been rarely studied. The goal of this study is to evaluate the sensory block resulting from erector spinae plane block applied at the T9 vertebral level. Materials and methods: this observational, prospective, blinded study was conducted on 50 adult patients undergoing laparoscopic abdominal surgery. All patients underwent bilateral erector spinae plane block at the T9 level after completion of the surgery while under general anesthesia. In order to further evaluate the sensory blockade, we divided the hemiabdomen-hemithorax region into 4 quadrants: dorsal-medial, dorsallaterel, ventral-lateral, and ventral-medial. The sensorial evaluation was performed using the pinprick test, 2 hours following the application of erector spinae plane block. Results: a total of 28 female and 22 male patients were examined in this study. Complete failure of the block was recorded in 7 patients, with no thoracic/lumbar segmental or quadrant involvement. Successful sensory block was achieved in 67% of the dorsolateral quadrants, 58% of the dorsomedial quadrants, 69% of the ventrolateral quadrants, and 55% of the ventromedial quadrants. Conclusion: cutaneous sensory block of erector spinae plane block at T9 vertebral level revealed variable results and low failure rates. Administration of erector spinae plane block for postoperative analgesia in thoracoabdominal surgeries requires further randomized controlled trials to confirm its effectiveness and convenience.Publication Open Access Mutations in AR or SRD5A2 genes: clinical findings, endocrine pitfalls, and genetic features of children with 46,XY DSD(Galenos Yayınevi, 2022) Akcan, Neşe; Uyguner, Oya; Baş, Firdevs; Toksoy, Güven; Karaman, Birsen; Abalı, Zehra Yavaş; Poyrazoğlu, Şükran; Aghayev, Agharza; Karaman, Volkan; Bundak, Ruveyde; Basaran, Seher; Darendeliler, Feyza; Altunoğlu, Umut; Avcı, Şahin; Faculty Member; Faculty Member; School of Medicine; 126174; N/AObjective: androgen insensivity syndrome (AIS) and 5 alpha-reductase deficiency (5 alpha-RD) present with indistinguishable phenotypes among the 46,XY disorders of sexual development (DSD) that usually necessitate molecular analyses for the definitive diagnosis in the prepubertal period. The aim was to evaluate the clinical, hormonal and genetic findings of 46,XY DSD patients who were diagnosed as AIS or 5 alpha-RD. Methods: patients diagnosed as AIS or 5 alpha-RD according to clinical and hormonal evaluations were investigated. Sequence variants of steroid 5-alpha-reductase type 2 were analyzed in cases with testosterone/dihydrotestosterone (T/DHT) ratio of >= 20, whereas the androgen receptor (AR) gene was screened when the ratio was <20. Stepwise analysis of other associated genes were screened in cases with no causative variant found in initial analysis. For statistical comparisons, the group was divided into three main groups and subgroups according to their genetic diagnosis and T/DHT ratios. Results: a total of 128 DSD patients from 125 non-related families were enrolled. Birth weight SDS and gestational weeks were significantly higher in 5 alpha-RD group than in AIS and undiagnosed groups. Completely female phenotype was higher in all subgroups of both AIS and 5 alpha-RD patients than in the undiagnosed subgroups. In those patients with stimulated T/DHT <20 in the prepubertal period, stimulated T/DHT ratio was significantly lower in AIS than in the undiagnosed group, and higher in 5 alpha-RD. Phenotype associated variants were detected in 24% (n=18 AIS, n=14 5 alpha-RD) of the patients, revealing four novel AR variants (c.94G>T, p.Glu32*, c.330G>C, p.Leu110=; c.2084C>T, p.Pro695Leu, c.2585_2592delAGCTCCTG, p.(Lys862Argfs*16), of these c.330G>C with silent status remained undefined in terms of its causative effects. Conclusion: T/DHT ratio is an important hormonal criterion, but in some cases, T/DHT ratio may lead to diagnostic confusion. Molecular is for the robust of 46,XY DSD Four novel AR variants were identified in our study.Publication Open Access Does resection of heterotopic ossification of the elbow result in satisfactory functional outcomes?(Galenos Yayınevi, 2019) Kapıcıoğlu, Mehmet; Sağlam, Yavuz; Ersen, Ali; Atalar, Ata, Can; Durmaz, Hayati; N/A; Demirhan, Mehmet; Faculty Member; School of Medicine; 9882Objective: heterotopic ossification (HO) is a common cause of elbow stiffness following surgical treatment of elbow trauma. In this study, our aim was to evaluate the mid-term functional outcomes of open surgical procedures for HO. Methods: in this retrospective study approved by the institutional review board (IRB), all patients who were diagnosed as having stiff elbow due to HO and underwent surgical resection at a single institution from 2006 to 2013 were included. Intrinsic (inside the joint) pathologies were excluded. Range of motion (ROM) in sagittal and coronal planes, complications, functional scores such as Quick Disabilities of the Arm, Shoulder and Hand Score (Q-DASH), and Mayo Elbow Performance Score (MEPS) were evaluated before and after surgery. Results: there were 19 patients (16 males, 3 females) with a mean age of 38.6 (range 15-69) years. At an average follow-up of 36 +/- 8 months, the mean flexion-extension arc was improved from 27.4 degrees to 99.2 degrees (p<0.001) and mean supination-pronation arc was improved from 48.9 degrees to 102.3 degrees (p<0.001). The mean Q-DASH score was decreased from 68.2 to 17.1 (p<0.001) and mean MEPS was improved from 37.5 to 85.6 (p<0.001). Conclusion: excision of heterotopic bone and releasing contracted tissues around elbow can provide a substantial increase in range of motion and improvement in clinical scores.Publication Open Access Aberrant methylation profile and microsatellit instability in Turkish sporadic colorectal carcinoma(Galenos Yayınevi, 2019) Ekmekçi, Cumhur Gökhan; Güllüoğlu, Mine; Dizdaroglu, Ferhunde; Özbek, Uğur; N/A; Kapran, Yersu; Faculty Member; School of Medicine; 168101Objective: genomic DNA obtained from paraffin blocks of the intended colorectal cancer cases was evaluated for promoting colorectal cancer by investigating the promoter methylation of 6 different gene promoter regions and microsatellite instability. Methods: DNA was isolated from the paraffin tissue of 76 sporadic colorectal cancer patients by cross sections from the areas determined to be tumorous. The methylation specific PCR (MS-PCR) method was used for these DNA samples fo rmethlylation studies in promoter region of six different APC, hMLH1, p16INK4A, p15, p73 and DAPK1 genes. In the same samples, the presence of microsatellite instability (MSI). Results: the fequencey of methylation was 24% for hMLH1, 31.5% for APC, 19.6% for DAPK1, 42.8% for p16, 30% for p15, 17% for p73. We calculated a methylation index (MI=ratio between the number of genes methylated and the number of genes analyzed). MI was ranged from 0-0.83, with an average of 0.271 corresponding to 1.6 genes/sample and median was 0.225 and there were 15 samples which doesn't methylated in any loci. We analysed MSI in C-kit (21%), hMSH2 (18%) and APC (15%), microsatellite region. Conclusion: we observed APC methylation was common then the other population for Turkish patient. P16 was the most commenest methylated loci among the 6 of gene and it seems storongly related with female patients. P73 was releated with left colorectal cancer and additionally it was related with the MSI.Publication Open Access Do dividend distributions and dividend commitments of a target company violate the prohibition of financial assistance (TCC Article 380/1)?(İstanbul Üniversitesi Yayınevi, 2018) Paslı, Ali; Veziroğlu, Cem; Faculty Member; Law School; 265198Pursuant to Turkish Commercial Code ("TCC") Article 380 paragraph 1, "[L]egal transactions concluded between the company and another person for acquisition of its shares and the subject of which is granting of advance, loan or security, shall be null and void." According to this provision, a public company cannot provide financial assistance to a third party with a view to acquiring its shares. This article examines a target company's dividend payout or commitment to its buyer (who would be a shareholder following an acquisition of the target company's shares) that is financed by a bank loan or from its retained earnings (i.e., without using any external source). We ask whether use of such funds in acquisition finance constitute "financial assistance" in the meaning of TCC 380/1. According to TCC, the prohibition of financial assistance applies only if three conditions exist cumulatively: (1) There must be an acquisition of shares; (2) there must be a financial assistance transaction, and (3) financial assistance must be made for the acquisition of shares. Therefore, the aforementioned transactional mechanism must be filtered through these three conditions. In our view, dividend payouts or commitments to the buyer following her share acquisition does not violate the prohibition of financial assistance, regardless of whether such amount is funded by a bank loan or the company's retained earnings. Using profits distributed by the target company in order to finance the acquisiton of the target company's shares makes no differrence according to our analysis. It is also possible that a commitment may be given for the target company's dividend payout in certain periods and for certain amounts in order to ensure repayment of the credit provided for the acquisition. The obligor of the said commitment may be the buyer or the target company (as a legal entity). If the target company is the obligor, the consequences for violating the commitment will vary according to the modality of the undertaking. Nonetheless, we believe that the target company's dividend payout must be made in compliance with the rules and procedures laid down by the TCC and by the company's articles of association. Otherwise, in addition to sanctions with respect to distribution of profit (TCC 512), the prohibition of financial assistance may step in. Hence, both the general assembly's resolution towards dividend payout and the payment of dividend (act of disposal) may be considered null and void regardless of whether the buyer's receipt of the dividend was wrongful and in bad faith. / 6102 sayılı Türk Ticaret Kanunu’nun (“TTK”) 380. maddesinin 1. fıkrası uyarınca “[P]aylarının iktisap edilmesi amacıyla, şirketin başka bir kişiyle yaptığı, konusu avans, ödünç veya teminat verilmesi olan hukuki işlemler batıldır”. Anılan hüküm, payları üçüncü kişi tarafından iktisap edilen anonim ortaklığın alıcıya finansal yardımda bulunmasını yasaklamaktadır. İşbu makalede incelediğimiz husus hedef anonim ortaklığın bir bankadan kredi temin etmesinin ardından söz konusu meblağı, yahut dış finansman kullanmaksızın birikmiş kârını, şirketin paylarını iktisap ederek pay sahibi sıfatını kazanan alıcıya kâr dağıtımı yoluyla aktarması ve bu kaynağın devralma işleminin finansmanında kullanılmasının TTK 380/1 anlamında “finansal yardım” sayılıp sayılmayacağıdır. Finansal yardım yasağının uygulama alanı bulabilmesi için şu üç şartın bir arada bulunması gerekmektedir. Bunlar; (1) pay iktisabı, (2) finansal yardım işlemi ve (3) finansal yardımın alıcının pay iktisabı amacıyla yapılmasıdır. O halde yukarıda açıklanan işlem örgüsü de bu üç şartın süzgecinden geçirilmelidir. Kanımızca bir bankanın anonim ortaklığa kredi temin etmesi ve söz konusu kredinin, anonim ortaklığın paylarını iktisap ederek pay sahibi sıfatını kazanan alıcıya kâr dağıtımı yoluyla aktarılması, yahut zaten hedef şirketin malvarlığına dâhil olan mevcut kaynağın kâr dağıtımı suretiyle alıcıya tahsis edilmesi TTK 380/1’de düzenlenen finansal yardım yasağının kapsamına girmemektedir. Ulaştığımız bu sonuç açısından, hedef şirketin nakit ihtiyacı sebebiyle bankanın sağlayacağı kredi neticesinde hedef şirketin dağıtacağı kârın, yine hedef şirketin paylarının iktisabı amacıyla kullanılacak olması da hiçbir fark yaratmamaktadır. Aynı şekilde, hedef şirketin paylarının iktisabının ve bunun finansmanı için sağlanan kredinin geri ödenmesini teminen, hedef şirketin belirli süreler içinde ve belirli oranlarda kâr dağıtımı yapacağına dair bir taahhüdün verilmiş olması da mümkündür. Söz konusu taahhüdün yükümlüsü alıcı olabileceği gibi, hedef şirket tüzel kişiliği de olabilir. Yükümlülüğün şirket üzerinde olması şeklindeki ikinci ihtimalde taahhüde aykırılığın sonuçları, taahhüdün veriliş şekline göre değişiklik gösterecektir. Ancak bunun için, hedef şirket nezdinde yapılacak kâr dağıtımının TTK ve esas sözleşmede öngörülen usul ve esaslara riayet edilerek gerçekleştirilmesi gerekmektedir. Aksi hâlde hedef şirket tarafından pay sahibine yapılacak malvarlığı aktarımına ilişkin kâr dağıtımını düzenleyen hükümlerde öngörülen yaptırımlara (TTK 512) ek olarak, finansal yardım yasağının da uygulanması riski doğabilecektir. Keza bu durumda pay sahibi konumundaki alıcının, kâr payını haksız yere ve kötü niyetle alıp almadığına bakılmaksızın, hem genel kurulun kâr payı dağıtım kararı hem de tasarruf işlemi niteliğindeki hedef şirketin temettü ödeme işlemleri kesin hükümsüz sayılabilecektir.Publication Open Access Lumbar plexus block performance for femur fracture for a Hamamy syndrome patient(Aves, 2022) Gürkan, Yavuz; Kalyoncu, İlayda; Gedik, Cemil Cihad; Manici, Mete; Gönen, Emel; Faculty Member; Resercher; Researcher; Faculty Member; Faculty Member; School of Medicine; 154129; 353184; 327612; 113502; 220454NAPublication Open Access Clinicopathologic and prognostic features in gallbladder malignancies: retrospective analysis of 5206 cases(Galenos Yayınevi, 2019) Ferhatoglu, Murat Ferhat; Kıvılcım, Taner; Kartal, Abdulcabbar; Gürkan, Alp; N/A; Şenol, Kazım; Doctor; School of MedicineAim: Gallbladder cancer is the sixth most common cancer of the gastrointestinal system. Clinical presentation may not be distinguished from cholelithiasis or cholecystitis and most patients are diagnosed intraoperatively or in the postoperative histologic examination. In this study, we aimed to investigate the association of incidentally detected gallbladder cancer with gallbladder premalignant lesions, age, gender, ultrasonography features and gallbladder stones. Methods: demographic and clinical characteristics and pathology results of 5206 patients who underwent cholecystectomy between January 2012 and December 2015 were evaluated retrospectively. Results: three thousand eight hundred and eighty four (74.6%) patients were female. Pathologic reports showed pre-malignant and malignant lesions in 102 (1.95%) cases. Metaplasia was significantly more common in females, while no significant difference was found in development of dysplasia and cancer between genders. Gallbladder stone was found to be a risk factor for the development of metaplasia. Gallbladder wall thickening and advanced age are the most important risk factors for gallbladder cancer. Conclusion: female gender and gallstone are important risk factors for the development of metaplasia. Advanced age, gallstone and gallbladder wall thickening on ultrasonography are the most important factors in the development cancer. Cholecystectomy should be kept in mind as the most effective method to prevent cancer development in elderly patients with gallbladder stones. / Amaç: safra kesesi kanseri, gastrointestinal sistemin en yaygın altıncı kanseridir. Klinik prezentasyon safra kesesi taşı veya kolesistitden ayırt edilemez ve çoğu hasta intraoperatif veya postoperatif histolojik incelemede tanı alır. Bu çalışmada, insidental olarak tespit edilmiş safra kesesi kanserli olguların safra kesesi pre-malign lezyonları, yaş, cinsiyet, ultrasonografi özellikleri ve safra kesesi taşı ile ilişkisi araştırılmıştır. Yöntemler: Ocak 2012-Aralık 2015 tarihleri arasında kolesistektomi uygulanan 5206 hastanın demografik ve klinik özellikleri, patoloji sonuçları retrospektif olarak değerlendirildi. Bulgular: hastaların 3884’ü (%74,6) kadındı. Patoloji raporlarında 102 (%1,95) olguda pre-malign ve malign lezyonlar olduğu tespit edildi. Metaplazi kadınlarda anlamlı olarak daha fazla iken, displazi ve kanser gelişimi arasında cinsiyete göre anlamlı bir fark bulunamadı. Safra kesesi taşı metaplazi gelişiminde bir risk faktörü olarak bulundu. Safra kesesi duvar kalınlaşmasının ve ileri yaşın safra kesesi kanseri gelişimi için en önemli risk faktörleri olduğu tespit edildi. Sonuç: metaplazi gelişiminde kadın cinsiyet ve taş varlığı önemli faktörlerdir. Ultrasonografide safra kesesi duvar kalınlaşması, ileri yaş, safra kesesinde taşı varlığı kanser gelişiminde en önemli faktörlerdir. Kolesistektomi, ileri yaşta safra kesesi taşı olan hastalarda kanser gelişimini önlemek için en etkili yöntem olarak akılda tutulmalıdır.Publication Open Access The situation of nursing education in Turkey during the Coronavirus-19 Pandemic(Aves, 2021) Karaöz, Sümeyye; Üstün, Besti; Doğan, Selma; Eroğlu, Kafiye; Faculty Member; School of Nursing; 6061Aim: in this research, it is aimed to determine how applied education in nursing is carried out in Turkey, the education-teaching methods used, the difficulties experienced, and solution suggestions during the COVID-19 pandemic. Methods: the sample of the descriptive study consisted of nursing education administrators of 80 universities in Turkey that provide undergraduate education in nursing. The data were collected online between February 2021 and March 2021, in the Qualtrics program, through a questionnaire containing 43 questions about the introductory features of the institution and educational management during the epidemic process. In the evaluation of the data, descriptive statistics such as number, percentage, and mean were used. Results: in 56.6% of the institutions, the number of students was over 500, the average number of students per instructor was 36.13 ± 17.71, and there were no instructors at the rate of 13-18.8% in the courses who have intensive credit and clinical practice; 52.5% of the administrators found the skill laboratory equipment in their schools partially sufficient; 52.5% of them had problems with education before the pandemic. During the pandemic, almost all of the schools held meetings (96.1%) on how to conduct education, and the university’s top management (82.5%) and higher education institution (73.7%) were most influential in the decisions taken. It was determined that while all of the theoretical courses were conducted remotely and hybrid, only 8.8% of the laboratories and 12.5% of the clinical/ field practices were conducted face-to-face. Almost all the administrators (96.5%) stated that they could not reach the learning outcomes due to the inability to perform clinical/ field practices. Administrators have easy access to the document of the course of distance education (72.5%); they stated that distance education has positive contributions to save time and flexibility of the course time (48.8%). Conclusion: the problems experienced in nursing education programs due to the COVID-19 pandemic, especially the inability to carry out laboratory and clinical/field applications, made it difficult to reach the educational goals. For this reason, it was concluded that practical education should be made face-to-face and the missing practices should be compensated.Publication Open Access Dimerization of pyrrole(TÜBİTAK, 1998) Yurtsever, Mine; Department of Chemistry; Yurtsever, İsmail Ersin; Faculty Member; Department of Chemistry; College of Sciences; 7129Accurate ab-inito quantum mechanical calculations of pyrrole dimers are reported. The thermodynamical stabilities of dimers with alpha - alpha, alpha -beta, and beta - beta type linkages are compared in order to predict the possibilities of branching in polypyrroles. Calculations employing large basis sets and including electron correlation effects predict the alpha - alpha dimers as the most stable form. However, an alpha - beta type bonding requires only 1.5-2.0 kcal/mol, and the energy necessary to introduce a beta - beta type bond is 3.6-4.0 kcal/mol. These values show that a high degree of branching is possible even at room temperatures.