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Publication 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 Open Access A new risk-scoring system for colorectal cancer and polyp screening by Turkish Colorectal Cancer and Polyp Study Group(Aves, 2022) Erdem, L.; Akbal, E.; Koçak, E.; Tucer, D.; Üçbilek, E.; Uyanıkoğlu, A.; Dolapçıoğlu, C.; Şirin, G.; Alkım, H.; Soylu, A.; Doğanay, L.; Kürbüz, A.K.; Özdil, K.; Alagözlü, H.; Erürker Öztürk, T.; Sezikli, M.; Adalı, G.; Çoban, M.; Hülagü, S.; Değertekin, H.; Atasoy, A.; Akyüz, F.; Gaffarlı, İ.; Saruç, M.; Altıntaş, E.; Sezgin, O.; Tözün N.; Ahıshalı, Emel; School of MedicineBackground: colorectal cancer is one of the most commonly diagnosed types of cancer worldwide. An early diagnosis and detection of colon cancer and polyp can reduce mortality and morbidity from colorectal cancer. Even though there are a variety of options in screening tests, the question remains on which test is the most effective for the early detection of colorectal cancer. In this prospective study, we aimed to develop a simple, useful, effective, and reliable scoring system to detect colon polyp and colorectal cancer. Methods: we enrolled 6508 subjects over the age of 18 from 16 centers, with colonoscopy screening. The age, smoking status, alcohol consumption, body mass index, polyp incidence, polyp size, number and localization, and pathologic findings were recorded. Results: the age, male gender, obesity, smoking, and family history were found as independent risk factors for adenomatous polyp. We have developed a new scoring system which can be used for these factors. With a score of 4 or above, we found the following: sensitivity 81%, specificity 40%, positive predictive value 25.68%, and negative predictive value 89.84%, for adenomatous polyp detection; and sensitivity 96%, specificity 39%, positive predictive value 3.35%, negative predictive value 99.29%, for colorectal cancer detection. Conclusion: even though the first colorectal cancer screening worldwide is generally performed for individuals over 50 years of age, we recommend that screening for colorectal cancer might begin for those under 50 years of age as well. Individuals with a score ? 4 must be included in the screening tests for colorectal cancer.
Publication Metadata only A Turkish 3-center study evaluation of serum folic acid and vitamin B12 levels in Alzheimer disease(Scientific and Technical Research Council Turkey (TUBITAK), 2015) Yılmaz, Gökhan; Erbayraktar, Zübeyde; Evlice, Ahmet Turan; Aras, Sevgi; Yener, Görsev; Avcı, Aslıhan; Ulusu, Nuriye Nuray; Faculty Member; School of Medicine; 6807Background/Aim: Alzheimer disease, a common proteopathy of advanced age, is characterized by cortical atrophy, neuron degeneration, neuronal loss, and accumulation of extracellular amyloid beta plaques. We aimed to investigate serum vitamin B12 and folic acid levels in Alzheimer disease and other dementia patients, as a potential screening test to detect presymptomatic Alzheimer disease in Turkish patients. Materials and Methods: We evaluated folic acid and vitamin B12 levels in Alzheimer disease patients as well as in other dementia and geriatric patients from Ankara, Dokuz Eylul, and Cukurova university hospitals; 290 female and male geriatric subjects were enrolled. Vitamin B12 and folic acid levels were measured using Roche E170 and Beckman Coulter DXI 800 immunoassays (chemiluminescence) according to the manufacturers' guideline in all centers. Results: We evaluated the results of folic acid and vitamin B12 in Alzheimer disease, other dementias and geriatric patients. No significant difference between the groups regarding the routine control of biochemical parameters was observed. Conclusion: Currently, serum folic and vitamin B12 levels are not diagnostically reliable tests for screening presymptomatic Alzheimer disease. However, the results may statistically be significant if we increase the sample size.Publication Metadata only A very rare case of cervicothoracic vertebral synostosis spanning eight adjacent segments: congenital vs acquired(Marmara Univ, Fac Medicine, 2018) Cengiç, İsmet; Altaş, Hilal; Buğdayci, Onur; N/A; Türeli, Derya; Doctor; N/A; Koç University Hospital; N/AAn elderly female presented with acute post-traumatic neck pain. Cervical roentgenogram revealed a long-segment cervicothoracic vertebral fusion spanning 8 adjacent spinal levels. The patient was evaluated with computed tomography (CT) and magnetic resonance (MR) imagings of the spine, electromyography (EMG) and growth differentiation factor 6 (GDF6) gene mutation analysis. Imaging findings were atypical for congenital block vertebrae and there was no GDF6 mutation. A revision of very old medical records and patient's recollections revealed long-term stay in sanatorium for rehabilitation of chronic partially-treated brucella spondylodiscitis during adolescence. Block vertebrae spanning several levels have previously been reported; but, this is the first report of an acquired cervicothoracic fusion spanning 8 adjacent vertebral bodies. / Yaşlı bir kadın hasta travma sonrası akut boyun ağrısı ile başvurdu. Servikal direkt grafisinde 8 ardışık spinal seviyeyi kapsayan uzun segment servikotorakal vertebral füzyon saptandı. Hasta spinal bilgisayarlı tomografi (BT) ve magnetik rezonans (MR) görüntüleme, elektromiyografi (EMG), ve büyüme-farklılaşma faktörü 6 [Growth differentiation factor 6 (GDF6)] gen mutasyonu analizi ile detaylı tetkik edildi. Görüntüleme bulguları konjenital blok vertebra için atipik olan olguda GDF6 gen mutasyonu saptanmadı. Hastanın eski tıbbi raporları ve anamnezinde adolesan dönemde kronik ve kısmen tedavi edilmiş brucella spondilodiskiti rehabilitasyonu amacıyla sanatoryumda uzun dönemli yatış mevcut idi. Birkaç seviyeyi kapsayan blok vertebra olguları daha önceden bildirilmiş olmakla birlikte; bu, 8 ardışık vertebral cismi kapsayan ilk edinsel servikotorakal füzyon olgusudur.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 Acil serviste Akdeniz benekli ateşi(Aves, 2015) Dikme, Özgür; Topaçoğlu, Hakan; Dikme, Özlem; Faculty Member; Koç University HospitalIntroduction: Mediterranean spotted fever (MSF) is one of the tick-borne rickettsial infections caused by Rickettsia conorii. In this case, we describe a patient who was admitted to the Emergency Department (ED) with persistent fever caused by MSF. Case Report: A 36-year-old male patient was admitted to the ED with persistent fever. Six days ago, antibacterial therapy had been started by his family practitioner; however, his fever continued. Upon admission on the seventh day of fever, the patient appeared ill. He had complaints such as malaise, myalgias, and nausea/vomiting. His fever was 38.6 degrees C, and other vital signs were normal. On physical examination, a single, crusted, ulcerated papule with a red halo resembling a cigarette burn was observed on the left leg. According to the diagnostic criteria for MSF, his score was 33, and he was admitted to the infectious disease department. Antibodies against Rickettsia were positive with the immunofluorescence assay. Fever after continuing for 24 hours reduced when a dose of 200 mg/daily doxycycline treatment was started. Conclusion: The aim of this presentation is to point out that MSF should be considered in the ED for the differential diagnosis of patient with a history of tick bite, persistent fever, maculopapular rash, headache, myalgia, arthralgia, and particularly with black eschar/tache noire.Publication Metadata only After a workshop on the novel antivirals for treatment of Hepatitis c virus infection (4-6 December 2015, İstanbul)(Aves, 2016) Aygen, Bilgehan; Aydın, Mehtap; Şimsek, Funda; Tekin, Süda; Faculty Member; School of Medicine; Koç University Hospital; 42146N/APublication Metadata only An alarming emergence of measles in Europe: gaps and future directions(Galenos Publ House, 2024) Ozsurekci, Yasemin; Ergönül, Önder; Koç Üniversitesi İş Bankası Enfeksiyon Hastalıkları Uygulama ve Araştırma Merkezi (EHAM) / Koç University İşbank Center for Infectious Diseases (KU-IS CID); School of MedicineN/APublication Open Access Antipacdus-pan: antibacterial utilization among adult patients before and during COVID-19 Pandemic within 12-months period: a tertiary hospital pharmacoepidemiology study(Design Oriented Community (DOC), 2022) Uçar, Ege Anıl; Karakuş, Mehmet Batuhan; Güldan, Mustafa; Şahin, Selin Merve; Şişman, Uluman; Baygül, Arzu Eden; Gülmez, Sinem Ezgi; Undergraduate Student; Undergraduate Student; Undergraduate 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; N/A; N/A; N/A; 272290; 281312Objective: irrational use of antibacterials is a concern during the COVID-19 pandemic. Hospital pharmacoepidemiology studies are important for evaluating the rational use of medicines, especially antibacterials, during pandemics. Defined daily doses (DDD) and drug utilization 90% (DU90%) are established methods for the evaluation of drug utilization. We aimed to evaluate antibacterial utilization in a tertiary hospital setting at Koç University Hospital (KUH). Materials and methods: this cross-sectional, descriptive study was retrospectively conducted with data extracted from KUH Inpatient Electronic Order System (CP) and was carried out for a period of one year. Antibacterial utilization of adult (aged ? 18 years) inpatients, who were prescribed at least one type of systemic antibacterial (ATC code J01), was evaluated using the recommended parameter DDD/100 admission and compared between 6 months before COVID-19 and during COVID-19 periods. March 11, 2020, the very first COVID-19 diagnosed case in Turkey, was set as the cutoff date of the 6-month period for the selection of the compared antibacterials using the DU90% method. Results: finally, 3280 of 5942 and 2605 of 4942 prescriptions for pre-COVID-19 and COVID-19 periods were included, respectively. Antibacterial utilization according to DDD/100 admissions increased from 193.96 to 201.26 DDD/100 admissions after the initiation of COVID-19 pandemic. The most utilized antibacterials were piperacillin and enzyme inhibitors in pre-COVID-19 period, whereas meropenem was utilized the most during COVID-19 period. Azithromycin utilization increased by 656.24%, whereas clarithromycin utilization decreased by 52.12%. Antibacterials were utilized most in general surgery department, with an increase of 17.57%. Conclusion: there is an increase in antibacterial utilization in KUH during COVID-19 pandemic, especially reserved antibacterials, which is a concern for antibacterial resistance.Publication Metadata only Artifact-removed quantitative analysis of choriocapillaris flow voids(Turkish Ophthalmological Association, 2023) Ersöz, M. Giray; Hocaoğlu, Mümin; Muslubaş, Işıl Sayman; Arf, Serra; Karaçorlu, Murat; N/A; Yıldız, Erdost; PhD Student; Graduate School of Health Sciences / Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM; N/A; N/AObjectives: To investigate choriocapillaris flow voids (FV) with a new optical coherence tomography angiography (OCTA) image processing strategy that can eliminate artifacts caused by vitreous opacities, sub-retinal pigment epithelium fluid and deposits, and subretinal fluid (SRF) by thresholding the en-face OCT image of the outer retina. Materials and Methods: We retrospectively reviewed medical records of patients with drusen and patients with active central serous chorioretinopathy (CSC). FV number (FVn), average area (FVav), and maximum area (FVmax) and the percentage of nonperfused choriocapillaris area (PNPCA) obtained using the proposed strategy were compared with those obtained by removing only artifacts caused by the superficial capillary plexus (SCP). Results: The SRF group included 21 eyes with active CSC and the drusen group included 29 eyes with nonexudative age-related macular degeneration. FVav, FVmax, FVn, and PNPCA obtained using the algorithm were significantly lower than those obtained by removing only SCP-related artefacts in both groups (all p<0.05). The algorithm was also able to remove 96.9% of artifacts secondary to vitreous opacities and all artifacts secondary to serous pigment epithelial detachments. Conclusion: Choriocapillaris nonperfusion areas on OCTA images may be overestimated in eyes with RPE abnormalities and SRF due to artifacts. These artifact areas on choriocapillaris OCTA images can be removed using thresholded images of the outer retina en-face OCT scans. Our new artifact-removal strategy is useful in the assessment of choriocapillaris FV in eyes with SRF, drusen, drusen-like deposits, and pigment epithelial detachment.