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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 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 Dimerization of pyrrole(TÜBİTAK, 1998) Yurtsever, Mine; Department of Chemistry; Department of Chemistry; Yurtsever, İsmail Ersin; Faculty Member; 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.Publication Open Access Discourse analysis: strengths and shortcomings(Center for Foreign Policy and Peace Research, 2019) Aydın-Düzgit, Senem; Department of International Relations; Department of International Relations; Rumelili, Bahar; Faculty Member; College of Administrative Sciences and Economics; 51356Discourse analysis is a much-favoured textual analysis method among constructivist and critically minded International Relations scholars interested in the impact of identity, meaning, and discourse on world politics. The aim of this article is to guide students of Turkish IR in their choice and use of this method. Written by two Turkish IR scholars who have employed discourse analysis in their past and present research, this article also includes a personal reflection on its strengths and shortcomings. The first section of the article presents an overview of the conceptual and epistemological underpinnings of discourse analysis, while charting the evolution of discourse analysis in IR since the late 1980s in three phases. The second section offers insight into the personal history of the researchers in employing discourse analysis in their previous and ongoing research, while the third section provides a how-to manual by performing discourse analysis of an actual text. The concluding section focuses on the challenges faced in the conduct of discourse analysis and the potential ways to overcome them, also drawing from the researchers'own experiences in the field.Publication Open Access Plane symmetric solutions of gravitational field equations in five dimensions(Scientific and Technological Research Council of Turkey (TUBITAK), 2006) Aliev, A.N.; Cebeci, H.; Department of Physics; Department of Physics; Dereli, Tekin; Faculty Member; College of Sciences; 201358We present the effective field equations obtained from a generalized gravity action with Euler-Poincaré term and a cosmological constant in a D dimensional bulk space-time. A class of plane-symmetric solutions that describe a 3-brane world embedded in a D = 5 dimensional bulk space-time are given.Publication Open Access The crime of failure by medical professionals to report an offence (TCC Art. 280)(İstanbul Üniversitesi Yayınevi, 2019) N/A; Özgüç, Levent Emre; Researcher; Law School; 265199The topic of analysis of this paper is the crime of "Failure by Medical Professionals to Report an Offence", found in article 280 of the Turkish Criminal Code numbered 5237. The crime is situated in the second part, titled "Crimes against the Judiciary", under the fourth section, titled "Crimes against the Nation and the State", under the second book of the Code, and is the equivalent of Article 530 of the annulled Turkish Criminal Code numbered 765. Pursuant to Art. 280, medical professionals who encounter an indication pointing towards a crime in the course of their duties, and do not notify the authorities of that fact or show delay in their notifications, are punishable by imprisonment. The lack of any limitation concerning the encountered crime which would create the obligation to report caused the medical professionals to face an obligation of substantial extent. Throughout the analysis of the crime, the doctrinal discussions concerning the crime are evaluated. In this context, the topics such as the norm's protected legal value, the scope of the term medical professional, the status of medical professionals in the public sector, the definition of the term indication in relation to the crime and whether documents and statements are included, whether the crime is committable by probable intent, whether the patient-doctor privilege, the right to be excused from testifying or the obligation to give treatment are justifications for the crime, and the rules of aggregation between TCC Art. 280 and similar crimes are explained. / Bu çalışmada, 5237 sayılı Türk Ceza Kanunu’nun 280. maddesinde düzenlenen “Sağlık Mesleği Mensuplarının Suçu Bildirmemesi” suçu ele alınmaktadır. Suç kanunun ikinci kitabının “Millete ve Devlete Karşı Suçlar” başlıklı dördüncü kısmının “Adliyeye Karşı Suçlar” başlıklı ikinci bölümünde yer almaktadır ve 765 sayılı mülga Türk Ceza Kanunu’nun “Cürmü Haber Vermekte Zühul” başlıklı 530. maddesinin karşılığıdır. 5237 sayılı TCK m 280 uyarınca, görevi sırasında belirtisiyle karşılaştığı bir suçu yetkili makamlara bildirmeyen veya bildirimde gecikme gösteren sağlık mesleği mensubu hapis cezasıyla cezalandırılmaktadır. Suç tanımında bildirim yükümlülüğünün doğmasına neden olacak suçlara ilişkin herhangi bir sınırlama yapılmamış olması sağlık mesleği mensuplarının oldukça geniş bir yükümlülükle karşı karşıya kalmasına sebep olmuştur. Suçun incelenmesi sırasında düzenlemeye ilişkin tartışmalar hakkında bilgi verilmiştir. Bu kapsamda suçla korunan hukuki değerin ne olduğu, failin sahip olması gereken sağlık mesleği mensubu kavramının kimleri kapsadığı, aynı zamanda kamu görevlisi olan sağlık mesleği mensuplarının suç bakımından durumları, suç işlendiğini gösteren belirti kavramının anlamı, belge ve beyanların bu kapsamda olup olmayacağı, suçun olası kastla işlenip işlenemeyeceği, sağlık mesleği mensubunun sır saklama yükümlülüğü, tanıklıktan çekinme hakkı veya tedavi yükümlülüğünün suçta hukuka aykırılığı kaldıran neden sayılıp sayılmayacağı, TCK m 280 ile benzer yükümlülükleri düzenleyen suçlar arasındaki içtima ilişkisi gibi hususlar çözülmeye çalışılmıştır.Publication Open Access Endovascular treatment of iliofemoral deep vein thrombosis in pregnancy using US-guided percutaneous aspiration thrombectomy(Aves, 2017) Gedikoğlu, Murat; N/A; Oğuzkurt, Levent; Faculty Member; School of MedicinePURPOSE: We aimed to describe ultrasonography (US)-guided percutaneous aspiration thrombectomy in pregnant women with iliofemoral deep vein thrombosis. METHODS: This study included nine pregnant women with acute and subacute iliofemoral deep vein thrombosis, who were severe symptomatic cases with massive swelling and pain of the leg. Patients were excluded from the study if they had only femoropopliteal deep vein thrombosis or mild symptoms of deep vein thrombosis. US-guided percutaneous aspiration thrombectomy was applied to achieve thrombus removal and uninterrupted venous flow. The treatment was considered successful if there was adequate venous patency and symptomatic relief. RESULTS: Complete or significant thrombus removal and uninterrupted venous flow from the puncture site up to the iliac veins were achieved in all patients at first intervention. Complete relief of leg pain was achieved immediately in seven patients (77.8%). Two patients (22.2%) had a recurrence of thrombosis in the first week postintervention. One of them underwent a second intervention, where percutaneous aspiration thrombectomy was performed again with successful removal of thrombus and establishment of in line flow. Two patients were lost to follow-up after birth. None of the remaining seven patients had rethrombosis throughout the postpartum period. Symptomatic relief was detected clinically in these patients. CONCLUSION: Endovascular treatment with US-guided percutaneous aspiration thrombectomy can be considered as a safe and effective way to remove thrombus from the deep veins in pregnant women with acute and subacute iliofemoral deep vein thrombosis.Publication Open Access Gonadotropin-releasing hormone agonist triggering of oocyte maturation in assisted reproductive technology cycles(Turkish Society of Obstetrics and Gynecology, 2015) Türkgeldi, Lale Wetherilt; Seyhan, Ayşe; Türkgeldi, Engin; Ata, Mustafa Barış; Faculty Member; Faculty Member; School of Medicine; Koç University Hospital; N/A; 182910Gonadotropin-releasing hormone agonists (GnRHa) have gained increasing attention in the last decade as an alternative trigger for oocyte maturation in patients at high risk for ovarian hyperstimulation syndrome (OHSS). They provide a short luteinizing hormone (LH) peak that limits the production of vascular endothelial growth factor, which is the key mediator leading to increased vascular permeability, the hallmark of OHSS. Initial studies showed similar oocyte yield and embryo quality compared with conventional human chorionic gonadotropin (hCG) triggering; however, lower pregnancy rates and higher miscarriage rates were alarming in GnRHa triggered groups. Therefore, two approaches have been implemented to rescue the luteal phase in fresh transfers. Intensive luteal phase support (iLPS) involves administiration of high doses of progesterone and estrogen and active patient monitoring. iLPS has been shown to provide satisfactory fertilization and clinical pregnancy rates, and to be especially useful in patients with high endogenous LH levels, such as in polycystic ovary syndrome. The other method for luteal phase rescue is low-dose hCG administiration 35 hours after GnRHa trigger. Likewise, this method results in statistically similar ongoing pregnancy rates (although slightly lower than) to those of hCG triggered cycles. GnRHa triggering decreased OHSS rates dramatically, however, none of the rescue methods prevent OHSS totally. Cases were reported even in patients who underwent cryopreservation and did not receive hCG. GnRH triggering induces a follicle stimulating hormone (FSH) surge, similar to natural cycles. Its possible benefits have been investigated and dual triggering, GnRHa trigger accompanied by a simultaneous low-dose hCG injection, has produced promising results that urge further exploration. Last of all, GnRHa triggering is useful in fertility preservation cycles in patients with hormone sensitive tumors. In conclusion, GnRHa triggering accompanied by appropriate luteal phase rescue protocols is a relatively safe option for patients at high risk for OHSS. / Gonadotropin salgılayıcı hormon agonistleri (GnRHa), ovaryan hiperstimülasyon sendromu (OHSS) açısından yüksek riskli olan hastalarda oosit matürasyonunun tetiklenmesi için bir alternatif olarak dikkat çekmişlerdir. Kısa süren bir lüteinizan hormon (LH) piki yarattıkları için OHSS’nin patogenezinde yatan artmış damar geçirgenliğinin sorumlusu vasküler endoteliyal büyüme faktörünün üretimini sınırlandırırlar. İnsan koryonik gonadotropin (hCG) ve GnRHa ile oosit matürasyonunun tetiklenmesini karşılaştıran ilk çalışmalarda, elde edilen oosit sayısı ve embryo kalitesi açısından iki grup arasında fark yokken, GnRHa kullanılan grupta gebelik oranlarının daha düşük ve gebelik kaybı oranlarının daha yüksek olduğu gözlenmiştir. Bu nedenle, taze transfer sikluslarında luteal fazın kurtarılması için iki yöntem geliştirilmiştir. Bunların ilki yoğun luteal faz desteği (iLPS) olup, yüksek doz progesteron ve östrojen verilmesini luteal fazing aktif takibini gerektirir. iLPS ile tatminkar fertilizasyon ve klinik gebelik oranları sağlanmış, polikistik ove sendromu gibi endojen LH seviyeleri yüksek olan hastalarda özellikle faydalı bulunmuştur. Luteal fazın kurtarılması için önerilen diğer yöntem ise GnRHa’dan 35 saat sonra düşük doz hCG uygulanmasıdır. Bu yöntemle, konvansiyonel hCG’dekine yakın (fakat bir miktar daha düşük) gebelik oranları elde edilmiştir. GnRHa kullanımı OHSS oranlarını belirgin biçimde düşürmekle birlikte, hiç bir yöntemin OHSS’yi tamamen ortadan kaldıramadığı bilinmelidir. hCG almayan ve doğrudan kriyoprezervasyon yapılan hastalarda dahi OHSS olguları bildirilmiştir. GnRHa ile oosit matürasyonunun tetiklenmesi sırasında, doğal sikluslardakine benzer bir folikül stimulan hormone artışı sağlanır. Bu artışın olası faydaları göz önüne alınarak ikili tetikleme (dual triggering) metodu geliştirilmiştir. GnRHa ile tetikleme sırasında düşük doz hCG uygulanmış, umut vadeden sonuçlar alınmıştır. Ayrıca, GnRHa ile oosit matürasyonu sağlanmasının, hormonlara duyarlı kanseri olan hastalarda fertilite korunmasında faydalı olabileceği gösterilmiştir. Sonuçta, GnRHa ile tetiklemeyi takiben uygun luteal faz kurtarma protokollerinin uygulanması OHSS açısından yüksek risk taşıyan hastalarda büyük ölçüde güvenli bir yöntemdir.