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Publication Open Access Effectiveness of posterior structures in the development of proximal junctional kyphosis following posterior instrumentation: a biomechanical study in a sheep spine model(Elsevier, 2019) Akgül, Turgut; Sarıyılmaz, Kerim; Özkunt, Okan; Dikici, Fatih; Yazıcıoğlu, Önder; N/A; Korkmaz, Murat; Doctor; School of MedicineIntroduction: proximal junctional kyphosis – PJK has been defined by a 10 or greater increase in kyphosis at the proximal junction as measured by the Cobb angle from the caudal endplate of the uppermost instrumented vertebrae (UIV) to the cephalad endplate of the vertebrae 1 segments cranial to the UIV. In this biomechanical study, it is aimed to evaluate effects of interspinosus ligament complex distruption and facet joint degeneration on PJK development. Materials and methods: posterior instrumentation applied between T2 – T7 vertebrae using pedicle screws to randomly selected 21 sheeps, divided into 3 groups. First group selected as control group (CG), of which posterior soft tissue and facet joints are protected. In second group (spinosus group, SG) interspinosus ligament complex which 1 segment cranial to UIV has been transected, and third group (faset group-FG) was applied facet joint excision. 25 N, 50 N, 100 N, 150 N and 200 N forces applied at frequency of 5 Hertz as 100 cycles axial to the samples. Then, 250 N, 275 N and 300 N forces applied static axially. Interspinosus distance, kyphosis angle and discus heights was measured in radiological evaluation. Abnormal PJK was defined by a proximal junctional angle greater than 100 and at least 100 greater than the corresponding preoperative measurement. Results: in CG group, average interspinosus distance was 6,6 ± 1.54 mm and kyphosis angle was 2,2 ± 0.46° before biomechanical testing, and they were measured as 9,4 ± 1.21 mm and 3,3 ±0.44° respectively after forces applied to samples. In SG group, average interspinosus distance was 6,2 ± 1.72 mm and kyphosis angle was 2,7 ± 1.01° before experiment, and they were measured as 20,8 ± 5.66 mm and 15,1 ± 2.34° respectively after forces applied to samples. In FG group, average interspinosus distance was 4,8 ± 1.15 mm and kyphosis angle was −1 ± 4.14° before experiment, and they were measured as 11,1 ±1.96mm and 11 ± 2.87° respectively after forces applied to samples. In comparison to group CG, statistically significant junctional kyphosis was seen on both FG and SG group after statistical analysis. (p < 0.05). PJK was seen statistically significant more on SG group than FG group. (p < 0.05). Not any statistically significant difference was seen on measurement of disk distances among three groups. (p > 0.05) Conclusions: protecting interspinosus ligament complex and facet joint unity during posterior surgical treatment for spine deformation is vital to prevent PJK development. Based on our literature review, this is the first biomechanical study that reveals interspinosus ligament complex are more effective on preventing PJK development than facet joints.Publication Open Access Rosiglitazone-induced changes in the oxidative stress metabolism and fatty acid composition in relation with trace element status in the primary adipocytes(Sciendo, 2019) N/A; Aydemir, Duygu; Sarayloo, Ehsan; Ulusu, Nuriye Nuray; PhD Student; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; N/A; N/A; 6807Metabolic syndrome, obesity and type 2 diabetes are metabolic disorders characterized by the insulin resistance and the impairment in the insulin secretion. Since impairment in the oxidative stress and adipocyte metabolism contribute to the formation of obesity and diabetes, targeting adipose tissue can be considered as an effective approach to fight against them. Rosiglitazone is used for treatment for patients with type 2 diabetes via inducing lipogenesis and transdifferentiation of white adipose tissue into brown adipose tissue. Since the development of such therapeutics is required to control the formation and function of brown fat cells, we aimed to reveal possible molecular mechanisms behind rosiglitazone induced biochemical changes in the adipose tissue. Cells were expanded in the adipocyte culture medium supplemented with 5 μg/mL insulin following 2 days' induction. After those cells were treated with rosiglitazone 0, 0.1 3 mol/L and 10 μmol/L rosiglitazone for 48 hours and at 8th day, cells were collected and stored at -80 °C. Then the cells were used to evaluate antioxidant enzyme activities, mineral and trace element levels and fatty acid composition. Glucose-6-phosphate dehydrogenase and glutathione reductase significantly reduced in rosiglitazone-treated groups compared to the control. Na, Mg, K, Ca, Cr, Fe, Ni, Cu, Zn, Rb, Sr, Cs, Ba and Pb were determined in the cell lysates via ICP-MS. Also, relative FAME content decreased in the rosiglitazone-treated groups compared to the control. Rosiglitazone treatment at low doses showed promising results which may promote brown adipose tissue formation.Publication Open Access Long-term prognosis of commercially sexually exploited youth in Turkey: brief report(Anadolu Psikiyatri Dergisi - Anatolian Journal of Psychiatry, 2017) Semerci, B.; Tufan, A. E.; Sanli, I.; N/A; Taşkıran, Ali Sarper; Other; School of Medicine; 195168Objective: Factors contribute to commercial sexual exploitation of youth (CSEY) and a variety of physical and psychological consequences of CSEY were previously discussed in the literature. The aim of the current study was to determine the long term prognosis of a sample of CSEY in Turkey. Methods: A sample of 108 CSEY (all females) with a mean age of 16.7 +/- 2.7 (range: 9-22) years living in a specialized center for protection against perpetrators were examined in terms of their sociodemographic variables, previous abuse history, family history and current psychopathology. Identified cases were referred for psychiatric evaluation. We obtained follow-up data 11 years after initial contact from this cohort (mean age 25.9 +/- 2.6 at time of follow-up) with the subjects and received information regarding their current functioning. Results: Follow up data revealed that recommendations during psychiatric follow up could not be acted upon. 71.4% of the initial sample (n= 76) could be reached via direct or indirect contacts. We found that good/superior functioning was very rare and that one-third of the sample that could be reached still was being sexually exploited. Important considerations derived from the results were discussed in the current article.Publication Open Access Homozygous, and compound heterozygous mutation in 3 turkish family with jervell and lange-nielsen syndrome: case reports(BioMed Central, 2017) Uysal, F.; Turkgenc, B.; Toksoy, G.; Bostan, O. M.; Evke, E.; Uyguner, O.; Yakicier, C.; Cil, E.; Temel, S. G.; N/A; Kayserili, Hülya; Faculty Member; School of Medicine; 7945Background: Jervell and Lange-Nielsen syndrome (JLNS) isa recessive model of long QT syndrome which might also be related to possible hearing loss. Although the syndrome has been demonstrated to be originated from homozygous or compound heterozygous mutations in either the KCNQ1 or KCNE1 genes, additional mutations in other genetic loci should be considered, particularly in malignant course patients. Case presentations: Three patients were admitted into hospital due to recurrent seizures/syncope, intrauterine and postnatal bradycardia respectively; moreover all three patients had congenital sensorineural hearing-loss. Their electrocardiograms showed markedly prolonged QT interval. Implantable defibrillator was implanted and left cardiac sympathetic denervation was performed due to the progressive disease in case 1. She had countless ventricular fibrillation and appropriate shock while using an implantable defibrillator. The DNA sequencing analysis of the KCNQ1 gene disclosed a homozygous c.728G > A (p.Arg243His) missense mutation in case1. Further targeted next generation sequencing of cardiac panel comprising 68 gene revealed a heterozygous c.1346 T > G (p.Ile449Arg) variant in RYR2 gene and a heterozygous c.809G > A (p.Cys270Tyr) variant in NKX2-5 gene in the same patient. Additional gene alterations in RYR2 and NKX2-5 genes were thought to be responsible for progressive and malignant course of the disease. As a result of DNA sequencing analysis of KCNQ1 and KCNE1 genes, a compound heterozygosity for two mutations had been detected in KCNQ1 gene in case 2: a maternally derived c.477 + 1G > A splice site mutation and a paternally derived c.520C > T (p.Arg174Cys) missense mutation. Sanger sequencing of KCNQ1 and KCNE1 genes displayed a homozygous c.1097G > A (p.Arg366Gln) mutation in KCNQ1 gene in case 3. beta-blocker therapy was initiated to all the index subjects. Conclusions: Three families of JLNS who presented with long QT and deafness and who carry homozygous, or compound heterozygous mutation in KCNQ1 gene were presented in this report. It was emphasized that broad targeted cardiac panels may be useful to predict the outcome especially in patients with unexplained phenotype-genotype correlation. Clinical presentations and molecular findings will be discussed further to clarify the phenotype genotype associations.Publication Open Access Clinical presentation in a series of eight children with abdominal tuberculosis: experience of a single-center in Turkey(Kowsar Publishing Corporation, 2017) Usta, Merve; Urgancı, Nafiye; Dalgıç, Nazan; Kurtaraner, Tuğce; Karadağ, Çetin Ali; N/A; Kızılkan, Nuray Uslu; Faculty Member; School of MedicineBackground: Abdominal tuberculosis, the sixth commonest extrapulmanory tuberculosis, is easily misdiagnosed due to nonspecific gastrointestinal symptoms. The diagnosis is highly dependent on clinician's suspicion of the disease; therefore to increase awareness we retrospectively reviewed clinical features of eight children in a four year-period. Methods: The medical records of children with abdominal TB were retrospectively reviewed. The diagnosis of abdominal TB was defined as Mycobacterium tuberculosis infection of gastrointestinal tract along with peritoneal or solid organ involvement. Results: There were six girls and two boys with a mean age of 13.6 +/- 2.8 years (range, 7 - 16 years). Abdominal pain and weight loss were common complaints in all patients (100%) at presentation; fever was present in four (50%) patients and abdominal distension in two (25%) patients. Mean duration of symptoms before diagnosis was 2.5 +/- 1 months. Laparotomy performed in six patients, and the peritoneum was the most common infection site (in 5 patients). Chest X-rays of 7 patients indicated lung involvement. The most common abdominal computed tomography and ultrasonography finding was ascites. Bowel wall thickening was recorded in 2 patients and ileal thickening in 1 patient. Inguinal lymphadenopathy and multiple mesenteric lymphadenitis were present as single cases. Conclusions: The abdominal tuberculosis should be suspected in children with ongoing abdominal pain, fever, and abdominal distension, laparoscopy or laparotomy could be useful in the differential diagnosis and utilizing imaging techniques, invasive methods with clinical suspicion may prevent delay of the diagnosis.Publication Open Access Transfer of the lesser tuberosity for reverse hill-sachs lesions after neglected posterior dislocations of the shoulder: a retrospective clinical study of 13 cases(Elsevier, 2017) Demirel, M.; Ersen, A.; Karademir, G.; Atalar, A.C.; N/A; Demirhan, Mehmet; Faculty Member; School of Medicine; 9882Objective: This study aimed to present middle-term functional and radiological outcomes of the transfer of the lesser tuberosity in the management of reverse Hill-Sachs lesions following posterior dislocations of the shoulder. Patients and methods: With a diagnosis of neglected posterior shoulder dislocation (8 locked, 5 recurrent), 13 male patients (age range: 28-72; mean age: 39.3 years) who underwent the transfer of the lesser tuberosity due to reverse Hill-Sachs lesions, were retrospectively reviewed based on functional and radiological data. The etiologies were: epilepsy in 9 patients, a traffic accident in 2 patients, and fall in 2 patients. To assess the patients' functional level, American Shoulder and Elbow Surgeons (ASES) and Constant Scores were used, and the patients' range of motion at the last follow-up was measured. To evaluate the development of arthrosis, the final follow-up control plain radiographs were examined. The average size of the defects calculated from the axial computed tomography sets was 27% (range: 20%-40%). Results: The average length of follow-up was 30 months (range: 12-67 months). At the last follow-up visit, the main ASES and Constant Scores were 78 and 85, respectively, and the average degrees of flexion, abduction, and external rotation were 163,151, and 70 respectively. The concentric reduction was observed postoperatively. Conclusion: McLaughlin procedure appears to be a safe and effective method in the treatment of neglected posterior shoulder dislocations with reverse Hill-Sachs lesion. Level of Evidence: Level IV, Therapeutic study. (C) 2017 Turkish Association of Orthopaedics and Traumatology.Publication Open Access Biomechanical comparison of orthogonal versus parallel double plating systems in intraarticular distal humerus fractures(Elsevier, 2017) Atalar, A. C.; Tunali, O.; Ersen, A.; Kapicioglu, M.; Saglam, Y.; N/A; Demirhan, Mehmet; Faculty Member; School of Medicine; 9882Objectives: In intraarticular distal humerus fractures, internal fixation with double plates is the gold standard treatment. However the optimal plate configuration is not clear in the literature. The aim of this study was to compare the biomechanical stability of the parallel and the orthogonal anatomical locking plating systems in intraarticular distal humerus fractures in artificial humerus models. Methods: Intraarticular distal humerus fracture (AO13-C2) with 5 mm metaphyseal defect was created in sixteen artificial humeral models. Models were fixed with either orthogonal or parallel plating systems with locking screws (Acumed elbow plating systems). Both systems were tested for their stiffness with loads in axial compression, varus, valgus, anterior and posterior bending. Then plastic deformation after cyclic loading in posterior bending and load to failure in posterior bending were tested. The failure mechanisms of all the samples were observed. Results: Stiffness values in every direction were not significantly different among the orthogonal and the parallel plating groups. There was no statistical difference between the two groups in plastic deformation values (0.31 mm-0.29 mm) and load to failure tests in posterior bending (372.4 N-379.7 N). In the orthogonal plating system most of the failures occurred due to the proximal shaft fracture, whereas in the parallel plating system failure occurred due to the shift of the most distal screw in proximal fragment. Conclusion: Our study showed that both plating systems had similar biomechanical stabilities when anatomic plates with distal locking screws were used in intraarticular distal humerus fractures in artificial humerus models. (C) 2016 Turkish Association of Orthopaedics and Traumatology.Publication Open Access Diffusion MRI features of acute encephalopathy due to stopping steroid medication abruptly in congentila adrenal hyperplasia(Medknow Publications, 2015) Serter, Aslı; Alkan, Alpay; N/A; Demirkol, Demet; Faculty Member; School of MedicineCongenital adrenal hyperplasia (CAH) is characterized by adrenal steroid biosynthesis defect. Steroid replacement therapy should be performed regularly in these patients. Adrenal crisis may be present in acute stress due to increased cortisol requirements or in steroid deficiency due to stopping steroid medication abruptly. In patients with acute adrenal insufficiency, severe hypotension or hypovolemic shock occurs typically. Acute encephalopathy can be seen due to hypoxia, hypervolemia, or hypoglycemia. Diffusion restriction can be seen in cortical-subcortical regions of frontal and parieto-occipital lobes and in splenium of corpus callosum. In CAH patients with neurologic symptoms, Diffusion weighted images (DWI) is very important in the diagnosis and follow-up of acute encephalopathy.Publication Open Access Screening for hepatic fibrosis and steatosis in Turkish patients with type 2 diabetes mellitus: a transient elastography study(Aves, 2019) Demir, Meryem; Yılmaz, Yusuf; N/A; Deyneli, Oğuzhan; Faculty Member; School of MedicineBackground/aims: non-alcoholic fatty liver disease is highly prevalent in patients with type 2 diabetes mellitus (T2DM). The aim of the present study was to investigate the potential usefulness of transient elastography (TE), which is a technique that allows measuring both fibrosis and liver fat content simultaneously, as a screening tool for hepatic involvement in Turkish patients with T2DM. Materials and methods: we obtained liver stiffness measurements (LSMs, as a measure of fibrosis) and controlled attenuation parameter (CAP, as a marker of steatosis) in 124 (46 males and 78 females; mean body mass index (BMI): 33.2 +/- 6.6 kg/m(2)) Turkish patients with T2DM. The prevalence rates of overweight, obesity, and metabolic syndrome in our sample were 28.2%, 64.5%, and 77.4%, respectively. Probe-specific LSM cut-off values were used to define advanced fibrosis (>= F3) and cirrhosis (F4) (M probe: F3=9.6-11.4 kPa, F4 >= 11.5 kPa and XL probe: F3=9.3-10.9 kPa, F4 >= 11.0 kPa). Mild, moderate, and severe steatosis were defined as CAP 222-232 dB/m, CAP 233-289 dB/m, and CAP >= 290 dB/m, respectively. Results: advanced fibrosis and cirrhosis were identified in 21 (16.9%) and 10 (8.0%) patients, respectively. TE-defined hepatic steatosis (CAP>222 dB/m) was detected in 117 (94.3%) patients. Mild, moderate, and severe steatosis were identified in 0, 29, and 88 patients, respectively. Conclusion: TE is a useful non-invasive imaging modality to screen for liver involvement in Turkish patients with T2DM. High rates of TE-defined fibrosis and steatosis in our sample reflect the presence of an elevated mean BMI.Publication Open Access Neuronal autoantibodies call for attention in epilepsy(Türk Nöropsikiyatri Derneği, 2017) Ekizoğlu, Esme; N/A; Vanlı-Yavuz, Ebru Nur; Doctor; School of Medicine