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Publication Metadata only 18F-FDG PET/CT mean suv and metabolic tumor volume for mean survival time in non-small cell lung cancer(Lippincott Williams and Wilkins, 2015) Kurtipek, Ercan; Çaycı, Mustafa; Düzgün, Nuri; Esme, Hıdır; Terzi, Yüksel; Bakdık, Süleyman; Ünlü, Yaşar; Burnik, Cengiz; Bekçi, Taha Tahir; N/A; Aygün, Murat Serhat; Teaching Faculty; School of Medicine; Koç University Hospital; 291692Objective: The study was designed to determine the relationship between survival time of standardized uptake value (SUVmax and SUVmean) and metabolic tumor volume (MTV) in patients with non-small cell lung cancer (NSCLC), and examine the impact of demographic, clinical, and radiological data of these patients on survival. Materials and Methods: We performed a retrospective analysis of the records of 79 patients with NSCLC who presented to our hospital between May 2010 and March 2013, received a final diagnosis, and underwent 18F-FDG PET/CT for staging. Clinical, radiological, and 18F-FDG PET/CT parameters with an impact on prognosis such as the SUVmax of the primary tumor as calculated by the volumetric region of interest in the 18F-FDG PET/CT scans during initial diagnosis, mean SUV of the tumor, and MTV obtained with a threshold of SUVmax greater than 2.5 were recorded and statistically analyzed. A statistical analysis was carried out based on the clinical, radiological, and PET/CT findings of the patients who were divided into 2 groups: survivors and nonsurvivors. Results: Seventy patients (88.6%) were men, and 9 (11.4%) were women. The mean age was 63.65 ± 11.51 years in the nonsurvivor group (n = 40) versus 62.74 ± 10.60 years in the survivor group (n = 39) (Table 1). The mean survival time from diagnosis was 7.9 ± 6.52 months in the nonsurvivor group versus 14.09 ± 7.41 months in the survivor group. The mean survival time was 12.9 ± 7.9 months for those aged 60 or younger, whereas it was 9.9 ± 7.2 years for those aged 60 or older. According to the Cox regression analysis, higher MTV [relative risk (RR), 1.006; P = 0.03] and mean SUVmax (mSUV) (RR, 1.302; P = 0.03) had a significant impact on shortening of the mean survival time. However, no statistical significance was reached for SUVmax measurements (RR, 0.970; P = 0.39). Furthermore, there was a significant relationship between increased tumor size (andlt;2 cm, 2-4 cm, and ≥4 cm) and shortened mean survival time (P = 0.03). Conclusion: The present study showed that MTV and mSUV of FDG PET/CT scans of the tumor, but not SUVmax, had a significant impact on survival time of patients with NSCLC. Based on this result, we believe that we might have more accurate information about the survival time of our patients if we also evaluate mSUV and MTV in combination with mSUV, which is frequently used for diagnosis and monitoring of patients with NSCLC during our daily practice. © 2015 Wolters Kluwer Health, Inc. All rights reserved.Publication Open Access A clinical scoring system to predict the development of bronchopulmonary dysplasia(Thieme Medical Publishers, 2015) Hayran, Mutlu; Derin, Hatice; Ovalı, Fahri; N/A; Gürsoy, Tuğba; Faculty Member; School of Medicine; 214691Objective: This study aims to develop a scoring system for the prediction of bronchopulmonary dysplasia (BPD). Methods: Medical records of 652 infants whose gestational age and birth weight were below 32 weeks and 1,500g, respectively, and who survived beyond 28th postnatal day were reviewed retrospectively. Logistic regression methods were used to determine the clinical and demographic risk factors within the first 72 hours of life associated with BPD, as well as the weights of these factors on developing BPD. Predictive accuracy of the scoring system was tested prospectively at the same unit. ResultsBirth weight, gestational age, gender, presence of respiratory distress syndrome, patent ductus arteriosus, intraventricular hemorrhage, hypotension were the most important risk factors for BPD. Therefore, a scoring system (BPD-TM score) ranging from 0 to 13 and grouped in four tiers (0-3: low, 4-6: low intermediate, 7-9: high intermediate, and 10-13: high risk) was developed based on these factors. Below the score of 4, 4.1% of infants (18/436), above the score of 9, 100% (29/29) of the infants developed BPD. The score was validated successfully in 172 infants. Conclusion: With this easy to use scoring system, one can predict the neonate at risk for BPD at 72 hours of life and direct preventive measures toward these infants.Publication Restricted A closer look at family medicine implementation in Turkey in regard to the doctor-patient relationship(Koç University, 2017) Ayar, Balacan Fatıma; Can, Başak Bulut; 0000-0002-4441-2272; Koç University Graduate School of Social Sciences and Humanities; Comparative Studies in History and Society; 219278Publication Open Access A combined VBM and DTI study of schizophrenia: bilateral decreased insula volume and cerebral white matter disintegrity corresponding to subinsular white matter projections unlinked to clinical symptomatology(Aves, 2017) Ulaşoğlu-Yıldız, Çiğdem; Aslan, Selçuk; Talı, Erhan Turgut; N/A; N/A; Onay, Aslıhan; Eser, Hale Yapıcı; Faculty Member; School of Medicine; N/A; 134359PURPOSE: Grey matter and white matter changes within the brain are well defined in schizophrenia. However, most studies focused on either grey matter changes or white matter integrity separately; only in limited number of studies these changes were interpreted in the same frame. In addition, the relationship of these findings with clinical variables is not clearly established. Here, we aimed to investigate the grey matter and white matter changes in schizophrenia patients and exhibit the relation of these imaging findings with clinical variables. METHODS: A total of 20 schizophrenia patients and 16 matched healthy controls underwent magnetic resonance imaging to investigate the grey matter and white matter alterations that occur in schizophrenia patients using voxel-based morphometry (VBM) and whole brain voxel-wise analysis of diffusion tensor imaging (DTI) parameters with SPM8, respectively. While the preprocessing steps ofVBM were performed with the default parameters of VBM8 toolbox, the preprocessing steps of DTI were carried out using FSL. Additionally, VBM results were correlated with clinical variables. RESULTS: Bilateral insula showed decreased grey matter volume in schizophrenia patients compared with healthy controls (P < 0.01). The opposite contrast did not show a significant difference. Psychiatric scores, duration of illness, and age were not correlated with the decreased grey matter volume of insula in schizophrenia patients. DTI analysis revealed a significant increase in mean, radial, and axial diffusivity, mainly of the fibers of bilateral anterior thalamic radiation and superior longitudinal fasciculus with left predominance, which intersected with bilateral subinsular white matter (P < 0.05). CONCLUSION: Our findings suggest that insula may be the main affected brain region in schizophrenia, which is also well supported by the literature. Our results were independent of disease duration and schizophrenia symptoms. White matter alterations were observed within bilateral anterior thalamic radiation and superior longitudinal fasciculus that intersects with subinsular white matter. Studies with larger sample sizes and more detailed clinical assessments are required to understand the function of insula in the neurobiology of schizophrenia.Publication Metadata only A common genetic variation of melanoma inhibitory activity-2 labels a subtype of pancreatic adenocarcinoma with high endoplasmic reticulum stress levels(Nature, 2015) Kong, Bo; Wu, Weiwei; Valkovska, Nataliya; Jäger, Carsten; Hong, Xin; Nitsche, Ulrich; Friess, Helmut; Esposito, Irene; Kleeff, Jörg; Michalski, Christoph W.; N/A; Erkan, Murat Mert; Faculty Member; School of Medicine; 214689HNF1 homeobox A (HNF1A)-mediated gene expression constitutes an essential component of the secretory pathway in the exocrine pancreas. Melanoma inhibitory activity 2 (MIA2), a protein facilitating protein secretion, is an HNF1A target. Protein secretion is precisely coordinated by the endoplasmic reticulum (ER) stress/unfolded protein response (UPR) system. Here, we demonstrate that HNFA and MIA2 are expressed in a subset of human PDAC tissues and that HNF1A induced MIA2 in vitro. We identified a common germline variant of MIA2 (c.A617G: p.I141M) associated with a secretory defect of the MIA2 protein in PDAC cells. Patients carrying MIA2I141M survived longer after tumor resection but the survival benefit was restricted to those patients who received adjuvant chemotherapy. The MIA2I141M variant was associated with high expression of ER stress/UPR genes – in particular those of the ERN1/XBP arm – in human PDAC samples. Accordingly, PDAC cell lines expressing the MIA2I141M variant expressed high levels of ERN1 and were more sensitive to gemcitabine. These findings define an interaction between the common MIA2I141M variant and the ER stress/UPR system and specify a subgroup of PDAC patients who are more likely to benefit from adjuvant chemotherapy. © 2015, Nature Research. All rights reserved.Publication Metadata only A late preterm infant with progressive respiratory distress(Marmara Univ, Fac Medicine, 2017) N/A; Gürsoy, Tuğba; Faculty Member; School of Medicine; Koç University Hospital; 214691A 2300 g female baby was born at 36+4 gestational age via caesarean section. Prenatal history was unremarkable. At 2 hours of age the baby was transferred to neonatal intensive care unit due to progressive respiratory distress and received poractant alfa as intubation-surfactant-extubation therapy after which FiO2 requirement decreased from 0.50 to 0.25. At 34 hours of age, while she was still on nasal continuous positive airway pressure (CPAP), she had sudden deterioration with retractions, desaturation and bradycardia. The infant was immediately intubated and put on high frequency oscillatory ventilation (HFOV) after which her oxygen saturations and heart rate stabilized.Publication Metadata only A low cost training phantom model for radio-guided localization techniques in occult breast lesions(Wiley, 2015) Aydoğan, Fatih; Mallory, Melissa Anne; Tükenmez, Mustafa; Sagara, Yasuaki; Özturk, Erkan; Çelik, Varol; Akça, Tamer; Golshan, Mehra; N/A; İnce, Hüseyin Yavuz; Faculty Member; School of Medicine; N/ARadio-guided localization (RGL) for identifying occult breast lesions has been widely accepted as an alternative technique to other localization methods, including those using wire guidance. An appropriate phantom model would be an invaluable tool for practitioners interested in learning the technique of RGL prior to clinical application. The aim of this study was to devise an inexpensive and reproducible training phantom model for RGL. We developed a simple RGL phantom model imitating an occult breast lesion from inexpensive supplies including a pimento olive, a green pea and a Turkey breast. The phantom was constructed for a total cost of less than $20 and prepared in approximately 10 min. After the first model's construction, we constructed approximately 25 additional models and demonstrated that the model design was easily reproducible. The RGL phantom is a time- and cost-effective model that accurately simulates the RGL technique for non-palpable breast lesions. Future studies are warranted to further validate this model as an effective teaching tool. J. Surg. Oncol. 2015; 112:449-451. © 2015 Wiley Periodicals, Inc.Publication Open Access A missed Behçet’s case presenting with spontaneous epidural hematoma(Aves, 2015) Karataş, Levent; Mengi, Gönen; N/A; Taşkıran, Özden Özyemişçi; Faculty Member; School of Medicine; 133091Spinal vascular events related to Behçet's disease are relatively uncommon. Deep vein thrombosis is the most frequent vascular involvement. Anticoagulant therapy is a debated issue in Behçet's disease. In this case report, we present a patient with a delayed diagnosis of Behçet's disease after development of cervical epidural hematoma following anticoagulant therapy due to deep venous thrombosis. Anticoagulant therapy without immunosuppressive therapy leading to uncontrolled systemic inflammation may be the cause of spinal epidural hematoma. On the other hand, epidural vascular involvement as a vasculitic manifestation of Behçet's disease in conjunction with anticoagulant therapy may have predisposed to spontaneous bleeding via increased fragility or microaneurysms in epidural arteries. In this case report, the importance of a multidisciplinary approach to Behçet's disease is emphasized.Publication Open Access A multi-center study on the efficacy of eltrombopag in management of refractory chronic immune thrombocytopenia: a real-life experience(Galenos Yayınevi, 2019) Çekdemir, Demet; Güvenç, Serkan; Özdemirkıran, Füsun; Eser, Ali; Toptaş, Tayfur; Özkocaman, Vildan; Haydaroğlu Şahin, Handan; Ermiş Turak, Esra; Esen, Ramazan; Cömert, Melda; Sadri, Sevil; Aslaner, Müzeyyen; Uncu Ulu, Bahar; Karakuş, Abdullah; Selim Bapur, Derya; Alacacıoğlu, İnci; Aydın, Demet; Tekinalp, Atakan; Namdaroğlu, Sinem; Ceran, Funda; Tarkun, Pınar; Kiper, Demet; Çetiner, Mustafa; Yenerel, Mustafa; Demir, Ahmet Muzaffer; Yılmaz, Güven; Terzi, Hatice; Atilla, Erden; Malkan, Ümit Yavuz; Acar, Kadir; Öztürk, Erman; Tombak, Anıl; Sunu, Cenk; Salim, Ozan; Alayvaz, Nevin; Sayan, Özkan; Ozan, Ülkü; Ayer, Mesut; Gökgöz, Zafer; Andıç, Neslihan; Kızılkılıç, Ebru; Noyan, Figen; Özen, Mehmet; Pepedil Tanrıkulu, Funda; Alanoğlu, Güçhan; Özkan, Hasan Atilla; Aslan, Vahap; Çetin, Güven; Akyol Erikçi, Alev; Deveci, Burak; Ersoy Dursun, Fadime; Dermenci, Hasan; Aytan, Pelin; Gündüz, Mehmet; Karakuş, Volkan; Özlü, Can; Demircioğlu, Sinan; Akay Yanar, Olga Meltem; Özatlı, Düzgün; Ündar, Levent; Tiftik, Eyüp Naci; Türköz Sucak, Ayhan Gülsan; Haznedaroğlu, İbrahim; Özcan, Muhit; Şencan, Mehmet; Tombuloğlu, Murat; Özet, Gülsüm; Bilgir, Oktay; Turgut, Burhan; Özcan, Mehmet Ali; Bahriye Payzın, Kadriye; Sönmez, Mehmet; Ayyıldız, Orhan; Dal, Mehmet Sinan; Ertop, Şehmus; Turgut, Mehmet; Soysal, Teoman; Kaya, Emin; Ünal, Ali; Pehlivan, Mustafa; Atagündüz, Işık; Tuğlular Fıratlı, Tülin; Saydam, Güray; Diz Küçükkaya, Reyhan; N/A; Çetiner, Mustafa; Öztürk, Erman; Faculty Member; Doctor; School of MedicineObjective: the aim of the present study was to evaluate the efficacy and safety of eltrombopag, an oral thrombopoietin receptor agonist, in patients with chronic immune thrombocytopenia (ITP). Materials and Methods: A total of 285 chronic ITP patients (187 women, 65.6%; 98 men, 34.4%) followed in 55 centers were enrolled in this retrospective cohort. Response to treatment was assessed according to platelet count (/mm3) and defined as complete (platelet count of >100,000/mm3), partial (30,000-100,000/mm3 or doubling of platelet count after treatment), or unresponsive (<30,000/mm3). Clinical findings, descriptive features, response to treatment, and side effects were recorded. Correlations between descriptive, clinical, and hematological parameters were analyzed. Results: The median age at diagnosis was 43.9±20.6 (range: 3-95) years and the duration of follow-up was 18.0±6.4 (range: 6-28.2) months. Overall response rate was 86.7% (n=247). Complete and partial responses were observed in 182 (63.8%) and 65 (22.8%) patients, respectively. Thirty-eight patients (13.4%) did not respond to eltrombopag treatment. For patients above 60 years old (n=68), overall response rate was 89.7% (n=61), and for those above 80 years old (n=12), overall response rate was 83% (n=10). Considering thrombocyte count before treatment, eltrombopag significantly increased platelet count at the 1st, 2nd, 3rd, 4th, and 8th weeks of treatment. As the time required for partial or complete response increased, response to treatment was significantly reduced. The time to reach the maximum platelet levels after treatment was quite variable (1-202 weeks). Notably, the higher the maximum platelet count after eltrombopag treatment, the more likely that side effects would occur. The most common side effects were headache (21.6%), weakness (13.7%), hepatotoxicity (11.8%), and thrombosis (5.9%). Conclusion: results of the current study imply that eltrombopag is an effective therapeutic option even in elderly patients with chronic ITP. However, patients must be closely monitored for response and side effects during treatment. Since both response and side effects may be variable throughout the follow-up period, patients should be evaluated dynamically, especially in terms of thrombotic risk factors. / Amaç: bu çalışmanın amacı kronik immün trombositopeni (ITP) hastalarında bir oral trombopoietin reseptör agonisti olan eltrombopagın etkinlik ve güvenirliliğini değerlendirmektir. Gereç ve Yöntemler: elli beş merkezde izlem altındaki toplam 285 kronik ITP hastası (187 kadın, %65,6) bu geriye dönük küme çalışmasına alınmıştır. Tedaviye yanıt trombosit sayısına göre değerlendirilmiş ve tam yanıt (>100.000/mm3), kısmi yanıt (30.000-100.000/mm3 veya tedaviden sonra trombosit sayısının bir kat artmış olması) ve yanıtsızlık (<30.000/mm3) olarak tanımlanmıştır. Hastaların klinik bulguları, tanımlayıcı özellikleri, tedaviye yanıt ve yan etki bilgileri toplanmış ve aralarındaki ilişki incelenmiştir. Bulgular: tanı anında yaş ortalaması 43,9±20,6 (3-95) yıl olan hastalar ortalama 18,0±6,4 (6-28,2) ay izlenmiştir. Tam ve kısmi yanıtı içeren toplam yanıt %86,7 (n=247) bulundu. Sırasıyla 182 (%63,8) ve 65 (%22,8) hastada tam ve parsiyel tedavi yanıtları gözlenmiştir. Otuz sekiz hasta (%13,4) eltrombopag tedavisine yanıt vermemiştir. Altmış yaş üzerindeki hastalarda (n=68) toplam yanıt %89,7 (n=61) bulunurken, bu oran 80 yaş üzerindeki (n=12) hastalarda %83 (n=10) olmuştur. Tedavi öncesi trombosit sayısı göz önüne alındığında, eltrombopag, tedavinin 1., 2., 3., 4. ve 8. haftalarında trombosit sayısını anlamlı şekilde artırmıştır. Kısmi veya tam cevap için gereken süre arttıkça, tedaviye cevap önemli ölçüde azaldığı saptanmıştır. Eltrombopag tedavisinden sonra maksimum trombosit sayısı ne kadar yüksekse, yan etkilerin oluşabilme ihtimalinin o kadar yüksek olabildiği dikkati çekmiştir. En sık görülen yan etkiler baş ağrısı (%21,6), güçsüzlük (%13,7) ve hepatotoksisite (%11,8) ve trombozdur (%5,9). Sonuç: Mevcut çalışmanın sonuçları, eltrombopag tedavisinin kronik ITP’de, yaşlı hastalar dahil olmak üzere, etkili bir tedavi seçeneği olduğunu göstermektedir. Bununla birlikte, hastalar tedavi sırasında yanıt ve yan etkiler açısından yakından izlenmelidir. Hem cevap hem de yan etkiler, takip süresi boyunca değişken olabileceğinden, hastalar özellikle tromboz risk faktörleri açısından dinamik olarak değerlendirilmelidir.Publication Open Access A new method to determine reflex latency induced by high rate stimulation of the nervous system(Frontiers, 2014) Karacan, İlhan; Çakar, Halil İ.; Cidem, Muharrem; Kara, Sadık; N/A; Yılmaz, Gizem; Sebik, Oğuz; Türker, Kemal Sıtkı; PhD Student; Researcher; Faculty Member; School of Medicine; N/A; N/A; 6741High rate stimulations of the neuromuscular system, such as continuous whole body vibration, tonic vibration reflex and high frequency electrical stimulation, are used in the physiological research with an increasing interest. In these studies, the neuronal circuitries underlying the reflex responses remain unclear due to the problem of determining the exact reflex latencies. We present a novel 'cumulated average method" to determine the reflex latency during high rate stimulation of the nervous system which was proven to be significantly more accurate than the classical method. The classical method, cumulant density analysis, reveals the relationship between the two synchronously recorded signals as a function of the lag between the signals. The comparison of new method with the classical technique and their relative accuracy was tested using a computer simulation. In the simulated signals the EMG response latency was constructed to be exactly 40 ms. The new method accurately indicated the value of the simulated reflex latency (40 ms). However, the classical method showed that the lag time between the simulated triggers and the simulated signals was 49 ms. Simulation results illustrated that the cumulated average method is a reliable and more accurate method compared with the classical method. We therefore suggest that the new cumulated average method is able to determine the high rate stimulation induced reflex latencies more accurately than the classical method.