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Publication Metadata only Coupled nonparametric shape and moment-based intershape pose priors for multiple basal ganglia structure segmentation(2010) Uzunbaş, Mustafa Gökhan; Soldea, Octavian; Ünay, Devrim; Çetin, Müjdat; Unal, Gozde Bozkurt; Erçil, Aytül; Ekin, Ahmet; Uzunbaş, Mustafa Gökhan, Faculty of Engineering and Natural Sciences, Sabancı Üniversitesi, Tuzla, Turkey, Department of Computer Science, Piscataway, United States; Soldea, Octavian, Faculty of Engineering and Natural Sciences, Sabancı Üniversitesi, Tuzla, Turkey; Ünay, Devrim, Department of Electrical and Electronic Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Çetin, Müjdat, Faculty of Engineering and Natural Sciences, Sabancı Üniversitesi, Tuzla, Turkey; Unal, Gozde Bozkurt, Faculty of Engineering and Natural Sciences, Sabancı Üniversitesi, Tuzla, Turkey; Erçil, Aytül, Faculty of Engineering and Natural Sciences, Sabancı Üniversitesi, Tuzla, Turkey; Ekin, Ahmet, Video Processing and Analysis Group, Philips Research, Eindhoven, NetherlandsThis paper presents a new active contour-based, statistical method for simultaneous volumetric segmentation of multiple subcortical structures in the brain. In biological tissues, such as the human brain, neighboring structures exhibit co-dependencies which can aid in segmentation, if properly analyzed and modeled. Motivated by this observation, we formulate the segmentation problem as a maximum a posteriori estimation problem, in which we incorporate statistical prior models on the shapes and intershape (relative) poses of the structures of interest. This provides a principled mechanism to bring high level information about the shapes and the relationships of anatomical structures into the segmentation problem. For learning the prior densities we use a nonparametric multivariate kernel density estimation framework. We combine these priors with data in a variational framework and develop an active contour-based iterative segmentation algorithm. We test our method on the problem of volumetric segmentation of basal ganglia structures in magnetic resonance images. We present a set of 2-D and 3-D experiments as well as a quantitative performance analysis. In addition, we perform a comparison to several existent segmentation methods and demonstrate the improvements provided by our approach in terms of segmentation accuracy. © 2010 IEEE. © 2010 Elsevier B.V., All rights reserved.Publication Metadata only Local and global volume changes of subcortical brain structures from longitudinally varying neuroimaging data for dementia identification(2012) Ünay, Devrim; Ünay, Devrim, Biomedical Engineering, Bahçeşehir Üniversitesi, Istanbul, TurkeyQuantification of structural changes in the human brain is important to elicit resemblances and differences between pathological and normal aging. Identification of dementia, associated with loss of cognitive ability beyond normal aging, and especially converters - the subgroup of individuals at risk for developing dementia - has recently gained importance. For this purpose atrophy markers have been explored and their effectiveness has been evaluated both cross-sectionally and longitudinally. However, more research is needed to understand the dynamics of atrophy markers at different disease stages, which requires temporal analysis of local along with global changes. Unfortunately, most of the longitudinal neuroimaging data available in the clinical settings is acquired at largely varying time intervals. In the light of the above, this study presents a novel methodology to process longitudinal neuroimaging data acquired incompletely and at different time intervals, and explores complementary nature of local and global brain volume changes in identifying dementia. Results on the OASIS database demonstrate discriminative power of global atrophy in hippocampus (as early as two years after the first visit) for identifying demented cases, and local volume shrinkage of thalamus proper (as early as three years after the first visit) for differentiating converters. © 2012 Elsevier Ltd. © 2013 Elsevier B.V., All rights reserved., MEDLINE® is the source for the MeSH terms of this document.Publication Metadata only Collection and analysis of a Parkinson speech dataset with multiple types of sound recordings(Institute of Electrical and Electronics Engineers Inc., 2013) Erdogdu Sakar, Betul; Isenkul, M. Erdem; Sakar, C. Okan; Sertbaş, Ahmet; Gürgen, Fïkret S.; Delil, Sakir; Apaydin, H.; Kursun, Olcay; Erdogdu Sakar, Betul, Department of Computer Programming, Bahçeşehir Üniversitesi, Istanbul, Turkey; Isenkul, M. Erdem, Department of Computer Engineering, Istanbul Üniversitesi, Istanbul, Turkey; Sakar, C. Okan, Department of Computer Engineering, Bahçeşehir Üniversitesi, Istanbul, Turkey; Sertbaş, Ahmet, Department of Computer Engineering, Istanbul Üniversitesi, Istanbul, Turkey; Gürgen, Fïkret S., Department of Computer Engineering, Boğaziçi Üniversitesi, Bebek, Turkey; Delil, Sakir, Department of Neurology, İstanbul University-Cerrahpaşa Cerrahpaşa Faculty of Medicine, Istanbul, Turkey; Apaydin, H., Department of Neurology, İstanbul University-Cerrahpaşa Cerrahpaşa Faculty of Medicine, Istanbul, Turkey; Kursun, Olcay, Department of Computer Engineering, Istanbul Üniversitesi, Istanbul, TurkeyThere has been an increased interest in speech pattern analysis applications of Parkinsonism for building predictive telediagnosis and telemonitoring models. For this purpose, we have collected a wide variety of voice samples, including sustained vowels, words, and sentences compiled from a set of speaking exercises for people with Parkinson's disease. There are two main issues in learning from such a dataset that consists of multiple speech recordings per subject: 1) How predictive these various types, e.g., sustained vowels versus words, of voice samples are in Parkinson's disease (PD) diagnosis? 2) How well the central tendency and dispersion metrics serve as representatives of all sample recordings of a subject? In this paper, investigating our Parkinson dataset using well-known machine learning tools, as reported in the literature, sustained vowels are found to carry more PD-discriminative information. We have also found that rather than using each voice recording of each subject as an independent data sample, representing the samples of a subject with central tendency and dispersion metrics improves generalization of the predictive model. © 2013 IEEE. © 2022 Elsevier B.V., All rights reserved.Publication Metadata only Genomic analysis of non-NF2 meningiomas reveals mutations in TRAF7, KLF4, AKT1, and SMO(American Association for the Advancement of Science, 2013) Clark, Victoria E.; Erson-Omay, Emine Zeynep; Harmancı, Akdes Serin; Yin, Jun; Cotney, Justin L.; Ozduman, Koray; Avşar, Timuçin; Li, Jie; Murray, Phillip B.; Henegariu, Octavian; Clark, Victoria E., Departments of Neurosurgery and Genetics, Yale School of Medicine, New Haven, United States; Erson-Omay, Emine Zeynep, Departments of Neurosurgery and Genetics, Yale School of Medicine, New Haven, United States; Harmancı, Akdes Serin, Departments of Neurosurgery and Genetics, Yale School of Medicine, New Haven, United States; Yin, Jun, Department of Genetics, Yale School of Medicine, New Haven, United States; Cotney, Justin L., Department of Genetics, Yale School of Medicine, New Haven, United States; Ozduman, Koray, Department of Neurosurgery, Acıbadem Mehmet Ali Aydınlar Üniversitesi, Istanbul, Turkey; Avşar, Timuçin, Dr. Orhan Öcalgiray Molecular Biology, İstanbul Teknik Üniversitesi, Istanbul, Turkey; Li, Jie, Department of Pathology, Yale School of Medicine, New Haven, United States; Murray, Phillip B., Departments of Neurosurgery and Genetics, Yale School of Medicine, New Haven, United States; Henegariu, Octavian, Departments of Neurosurgery and Genetics, Yale School of Medicine, New Haven, United StatesWe report genomic analysis of 300 meningiomas, the most common primary brain tumors, leading to the discovery of mutations in TRAF7, a proapoptotic E3 ubiquitin ligase, in nearly one-fourth of all meningiomas. Mutations in TRAF7 commonly occurred with a recurrent mutation (K409Q) in KLF4, a transcription factor known for its role in inducing pluripotency, or with AKT1E17K, a mutation known to activate the PI3K pathway. SMO mutations, which activate Hedgehog signaling, were identified in ∼5% of non-NF2 mutant meningiomas. These non-NF2 meningiomas were clinically distinctive - nearly always benign, with chromosomal stability, and originating from the medial skull base. In contrast, meningiomas with mutant NF2 and/or chromosome 22 loss were more likely to be atypical, showing genomic instability, and localizing to the cerebral and cerebellar hemispheres. Collectively, these findings identify distinct meningioma subtypes, suggesting avenues for targeted therapeutics. © 2015 Elsevier B.V., All rights reserved.Publication Metadata only Thyroid dyshormonogenesis is mainly caused by TPO mutations in consanguineous community(2013) Cangül, Hakan; Aycan, Zehra; Olivera-Nappa, Alvaro; Saǧlam, Halil; Schoenmakers, Nadia A.; Boelaert, Kristien; Çetinkaya, Semra Çaǧlar; Tarim, Ömer Faruk; Böber, Ece; Darendeli̇Ler, Feyza F.; Cangül, Hakan, Department of Medical Genetics, Bahçeşehir Üniversitesi, Istanbul, Turkey, Centre for Rare Diseases and Personalised Medicine, University of Birmingham, Birmingham, United Kingdom; Aycan, Zehra, Division of Paediatric Endocrinology, Children's Hospital, Ankara, Turkey; Olivera-Nappa, Alvaro, Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom; Saǧlam, Halil, Department of Paediatric Endocrinology, Bursa Uludağ Üniversitesi, Bursa, Turkey; Schoenmakers, Nadia A., University of Cambridge, Cambridge, United Kingdom; Boelaert, Kristien, Centre for Endocrinology, Diabetes and Metabolism, University of Birmingham, Birmingham, United Kingdom; Çetinkaya, Semra Çaǧlar, Division of Paediatric Endocrinology, Children's Hospital, Ankara, Turkey; Tarim, Ömer Faruk, Department of Paediatric Endocrinology, Bursa Uludağ Üniversitesi, Bursa, Turkey; Böber, Ece, Department of Pediatrics, Dokuz Eylül Üniversitesi, Izmir, Turkey; Darendeli̇Ler, Feyza F., Pediatric Endocrinology Unit, İstanbul Tıp Fakültesi, Istanbul, TurkeyObjective In this study, we aimed to investigate the genetic background of thyroid dyshormonogenesis (TDH). Context Thyroid dyshormonogenesis comprises 10-15% of all cases of congenital hypothyroidism (CH), which is the most common neonatal endocrine disorder, and might result from disruptions at any stage of thyroid hormone biosynthesis. Currently seven genes (NIS, TPO, PDS, TG, IYD, DUOX2 and DUOXA2) have been implicated in the aetiology of the disease. Design As TDH is mostly inherited in an autosomal recessive manner, we planned to conduct the study in consanguineous/multi-case families. Patients One hundred and four patients with congenital TDH all coming from consanguineous and/or multi-case families. Measurements Initially, we performed potential linkage analysis of cases to all seven causative-TDH loci as well as direct sequencing of the TPO gene in cases we could not exclude linkage to this locus. In addition, in silico analyses of novel missense mutations were carried out. Results TPO had the highest potential for linkage and we identified 21 TPO mutations in 28 TDH cases showing potential linkage to this locus. Four of 10 distinct TPO mutations detected in this study were novel (A5T, Y55X, E596X, D633N). Conclusions This study underlines the importance of molecular genetic studies in diagnosis, classification and prognosis of CH and proposes a comprehensive mutation screening by new sequencing technology in all newly diagnosed primary CH cases. © 2012 John Wiley & Sons Ltd. © 2014 Elsevier B.V., All rights reserved., MEDLINE® is the source for the MeSH terms of this document.Publication Metadata only Interaction between cardioverter defibrillator and enhanced external counterpulsation device(2013) Çelik, Ömer Faruk; Aydin, Alper; Yılmazer, Mustafa Serdar; Sarıgül, Nedim Umutay; Gürol, Tayfun; Daǧdeviren, Bahadïr; Çelik, Ömer Faruk, Department of Cardiology, Training and Research Hospital, Istanbul, Turkey; Aydin, Alper, Department of Cardiology, Bahçeşehir Üniversitesi, Istanbul, Turkey; Yılmazer, Mustafa Serdar, Department of Cardiology, T.C. Maltepe Universitesi Tip Fakültesi, Istanbul, Turkey; Sarıgül, Nedim Umutay, Department of Cardiology, T.C. Maltepe Universitesi Tip Fakültesi, Istanbul, Turkey; Gürol, Tayfun, Department of Cardiology, Bahçeşehir Üniversitesi, Istanbul, Turkey; Daǧdeviren, Bahadïr, Department of Cardiology, Bahçeşehir Üniversitesi, Istanbul, TurkeyBackground Potential interference between implanted cardiac devices and other medical instruments is an important concern. Therefore, we aimed to investigate the possible device interaction between implantable cardioverter defibrillators (ICDs) and external enhanced counterpulsation (EECP) treatment. Methods Twenty-one patients with an implanted ICD or cardiac resynchronization therapy with defibrillator (CRT-D) were enrolled into the study. EECP had applied as two sessions of 5 minutes. Data from device interrogations before and after the first EECP session and during second EECP session were recorded and analyzed for signs of possible device interaction. Results There was no sign of inappropriate sensing or noise during EECP session. There was no difference regarding electrode impedance, pacing, and sensing values before and after EECP. There was a statistically significant difference regarding heart rates during EECP therapy between rate response off and on modes (68.69 ± 5.92 beats/min and 90.32 ± 11.05 beats/min, respectively P = 0,001). In four patients with CRT-D and unipolar left ventricular pacing, counterpulsation could not be done because of QRS sensing problems. Conclusions EECP seems to be a safe treatment modality in patients with implanted ICD and CRT-D devices. It should be kept in mind that in those patients with CRT-D, rate responsive mode is on, inappropriate sinus tachycardia can be seen during EECP therapy. Also in patients with CRT-D using a unipolar sensing mode, problems of QRS complex sensing by the EECP may occur and, therefore, this effects synchronization and success of EECP therapy. ©2013, The Authors. Journal compilation ©2013 Wiley Periodicals, Inc. © 2013 Elsevier B.V., All rights reserved.Publication Metadata only Pure brucellar discitis mimicking lumbar disc herniation: A case report and review of the literature, Lomber disk hernisini taklit eden saf brusellar diskit: Bir olgu sunumu ve literatürün gözden geçirilmesi(2013) Ekşi̇, Murat Şakir; Bayri, Yasar; Özen, Ali; Daǧçinar, Adnan; Konya, Deniz; Ekşi̇, Murat Şakir, Marmara Üniversitesi Tip Fakültesi, Istanbul, Turkey; Bayri, Yasar, Marmara Üniversitesi Tip Fakültesi, Istanbul, Turkey; Özen, Ali, Marmara Üniversitesi Tip Fakültesi, Istanbul, Turkey; Daǧçinar, Adnan, Marmara Üniversitesi Tip Fakültesi, Istanbul, Turkey; Konya, Deniz, Bahçeşehir Üniversitesi, Istanbul, TurkeyBrucellosis is a zoonotic infection, endemic in the Middle East, the Mediterranean region, Central and South America. Osteoarticular involvement is the most common form of the disease process with spinal complications in third place in this group. We presented a 36-yearold male patient with signs and symptoms of lumbar disc herniation. On lumbar magnetic resonance imaging, a right-sided L5-S1 disc extrusion was detected and the patient was operated. Frozen material pointed out an inflammatory process with Brucella melitensis in disc specimen culture. He was put on rifampicin and doxycycline chemotherapies. After 6 months of follow-up, his clinical, laboratory, and radiological findings became normal. Medical treatment was stopped with ongoing routine outpatient follow-ups. Discitis without spondylitis in Brucella infection is very rare. There have been 2 case reports in the literature. Also, Brucella disc infection should be in differential diagnosis of lumbar disc herniation clinic in endemic parts of the world. © 2013 Elsevier B.V., All rights reserved.Publication Metadata only Posttraumatic stress disorder among Turkish veterans of the southeast, Güneydoǧu gazilerinde travma sonrasi{dotless} stres bozukluǧu geliģimi(2013) Güloǧlu, Berna; Karaırmak, Özlem; Güloǧlu, Berna, Bahçeşehir Üniversitesi, Istanbul, Turkey; Karaırmak, Özlem, Bahçeşehir Üniversitesi, Istanbul, TurkeyObjective: Traumatic events induced deliberately by humans such as terrorism causes posttraumatic stress disorder (PTSD) and other psychiatric disorders. Data analysis of the present study consists of two phases. At first phase, the prevalence of PTSD and depression comorbid to PTSD of veterans who were physically injured while doing their military service at South East Region was investigated. At the second phase, the role of risk factors of negative changes at the relationship with their environment and the need of psychological help on developing PTSD and depression comorbid to PTSD was examined. Methods: The study conducted with 247 southeast veterans. Age range of veterans is 24-49 (36.55±5.29). The years after the injury ranged from 2 to 28 years (15.35±5.3). All participants were evaluated with Demographic Information Questionnaire and Traumati Stress Symptom Checklist (TSSC). Findings: The prevalence of PTSD was %29.6, depression comorbid to PTSD %16.6. There was a significant difference on PTSD and depression comorbid to PTSD among veterans who reported negative changes in the relationship with their environment and veterans who don't reported negative changes in the relationship with their environment. Similarly, there was a significant difference on PTSD and depression comorbid to PTSD between veterans who need of psychological help and veterans who don't need psychological help. However, there was no significant interaction effect among veterans who reported negative changes in the relationship with their environment and need of psychological help. Discussion: Southeast veterans are under the risk of direct death treat such as taking a part in battle or facing with mine explosion. Therefore, psychological and psychiatric services should be constituted to those who are physically injured and veterans who done military service at that region but not injured. Although it has been a long time, PTSD and depression comorbid to PTSD was found among southeast veterans who were exposed to frequent life-threatening traumatic experiences such as being in the middle of battle or stepping on mine. Since it is observed that both having a negative relationships with their surroundings and the need of psychological help increase the probability of PTSD and depression comorbid to PTSD, institutions which will provide psychological and psychiatric services to veterans deployed in the area should established. © 2013 Elsevier B.V., All rights reserved.Publication Metadata only Cardiovascular effects of abduction shoulder sling in elderly patients, Is it really safe?(Springer Verlag, 2013) Canbora, Mehmet Kerem; Kose, Ozkan; Gürkan, Ufuk; Polat, Atillâ; Erdem, Şevki; Haklar, Uğur; Canbora, Mehmet Kerem, Department of Orthopaedics and Traumatology, Haydarpasa Numune Egitim ve Arastýrma Hastanesi, Istanbul, Turkey; Kose, Ozkan, Department of Orthopaedics and Traumatology, Antalya Training and Research Hospital, Antalya, Turkey, Kultur mah, Antalya, Turkey; Gürkan, Ufuk, Department of Cardiology, Siyami Ersek Thoracic and Cardiovascular Surgery Center, Istanbul, Turkey; Polat, Atillâ, Department of Orthopaedics and Traumatology, Haydarpasa Numune Egitim ve Arastýrma Hastanesi, Istanbul, Turkey; Erdem, Şevki, Department of Orthopaedics and Traumatology, Haydarpasa Numune Egitim ve Arastýrma Hastanesi, Istanbul, Turkey; Haklar, Uğur, Department of Orthopaedics and Traumatology, Bahçeşehir Üniversitesi, Istanbul, TurkeyObjective: The purpose of the prospective study is to investigate the cardiovascular effects of abduction shoulder sling (ASS) in elderly patients who underwent rotator cuff surgery. Methods: The study included 49 consecutive patients older than 50 years (mean 59.3 ± 8.2 years) who underwent arthroscopic rotator cuff repair surgery and used ASS in postoperative period. All cases underwent Holter electrocardiographic monitoring before (24 h) and after (48 h) the operation. The Holter findings were read by an experienced cardiologist and a pause of longer than 3 s and heart rate of <40 bpm was evaluated as significant bradycardia. Results: One patient (61-year-old male) described feeling faint (presyncope) which was confirmed with the Holter finding of a pause more than 3 s which occurred in the day time. Two other patients (52-year-old male, and 62-year-old female) reported severe dizziness (hypotensive attack) which required admission to a general practitioner. However, Holter findings were normal in these patients. These three cases were referred to cardiology department for evaluation of carotid hypersensitivity syndrome (CSH). CSH was confirmed with tests made with provocative maneuvers in a sitting position. CSH was defined as at least 3 s of asystole (cardio-inhibitor type) during carotid massage or systolic blood pressure falling below 50 mmHg (vaso-depressor type). All three patients were obese patients and BMI was higher than 30. Conclusions: ASS may trigger CSH in short necked and obese patients by exerting mechanical stimulation to the carotid sinus. These patients should be informed about symptoms and signs of CSH and educated on the proper use of ASS and correct positioning of shoulder strap. CSH should be kept in mind in patients who present with dizziness, presyncope and palpitation during the postoperative period. © 2013 Springer-Verlag Berlin Heidelberg. © 2021 Elsevier B.V., All rights reserved.Publication Metadata only Turkish nursing students' knowledge of and attitudes towards patients with HIV/AIDS(2013) Akin, Semiha; Mendi, Basak; Mendi, Onur; Durna, Zehra; Akin, Semiha, Nursing Department, Bahçeşehir Üniversitesi, Istanbul, Turkey; Mendi, Basak, Faculty of Health Sciences, Bahçeşehir Üniversitesi, Istanbul, Turkey; Mendi, Onur, Distance Education Department, Bahçeşehir Üniversitesi, Istanbul, Turkey; Durna, Zehra, Faculty of Health Sciences, Bahçeşehir Üniversitesi, Istanbul, TurkeyAims and objectives: To assess nursing students' knowledge of and attitudes towards such patients and to determine the variables associated with students' knowledge and attitudes towards them. Background: Improving nurses' and nursing students' knowledge and attitudes towards patients with HIV/AIDS is vital for providing quality care for such patients. Design: This descriptive, cross-sectional study was conducted at three nursing schools located in two different cities in Turkey. The inclusion criteria for the nursing students were as follows: being at least 18 years old, being a first-, second-, third- or fourth-year nursing student, and giving consent to participate in the research. Methods: The sample comprised 580 nursing students. The study used three data collection tools: (1) the Student Socio-Demographic Questionnaire, (2) the HIV/AIDS Knowledge Questionnaire and (3) the HIV/AIDS Attitude Questionnaire. Results: Participants' knowledge was found to be insufficient, particularly with regard to HIV transmission routes. They generally had positive attitudes towards patients with HIV/AIDS. However, they expressed some concerns and were hesitant about working with AIDS and HIV-positive patients. Conclusions: The current results reveal that nursing students still have misconceptions and a lack of knowledge of HIV/AIDS and that their attitudes need to be improved. Relevance to clinical practice: Improving education programmes about HIV/AIDS and using information sources effectively may contribute to better knowledge and more desirable attitudes towards HIV/AIDS. © 2013 John Wiley & Sons Ltd. © 2013 Elsevier B.V., All rights reserved.