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Publication Metadata only 5-HT causes venodilatation to reduce blood pressure in the rat(Karger, 2016) Seitz, Bridget M.; Krieger-Burke, Theresa; Darios, Emma S.; Thompson, Janice M.; Watts, Stephanie W.; N/A; Orer, Hakan S.; Faculty Member; School of Medicine; 53477N/APublication Metadata only A 3-year-old child with multi-drug resistant epilepsy responding to pharmacological and nonpharmacological treatments(Taylor & Francis, 2022) Yıldırım, Canan; N/A; Coşkun, Yeşim; Doctor; N/A; Koç University Hospital; N/AIntroduction: Despite the development of new antiseizure drugs (ASDs), around one third of epilepsy patients become refractory to treatment or experience adverse events due to ASDs. Therefore, discovery of new ASDs and new therapy options are crucial to improve the quality of life. Herein, we report a 3-year-old child with multi-drug resistant epilepsy caused by perinatal asphyxia whose seizures were reduced by 90% after the introduction of ketogenic diet, vagal nerve stimulation (VNS) AspireSR (SR-seizure response) and oral cannabidiol.Case presentation: A 9-month-old female infant had a history of multidrug resistant epilepsy due to perinatal asphyxia. At admission, she was experiencing up to 20-25 seizures per day lasting for 2-3 minutes. In addition to antiseizure drugs (ASDs), she was put on ketogenic diet (KD), vagal nerve stimulation (VNS) aspire seizure response (AspireSR) was inserted and oral cannabidiol (CBD) was started sequentially. Using pharmacological and nonph armacological therapies, her seizures have been reduced by 90%.Conclusion: The concurrent use of pharmacological and nonpharmacological therapies may be beneficial to improve seizures in infants with multi- Furthermore, our patient is the youngest child inserted VNS AspireSR in Turkey.Publication Metadata only A 52-year-old man with progressive weakness and incontinence(Sage, 2022) Danyeli, Ayca Ersen; Bozkurt, Subutay Berke; Uysal, Sanem Pinar; Akpek, Sergin; Kahyaoglu, Bulent; Peker, Selcuk; Altıntaş, Ayşe; Aygün, Murat Serhat; Akay, Olga Meltem; Üre, Ümit Barbaros; Ferhanoğlu, Ahmet Burhan; Faculty Member; Teaching Faculty; Faculty Member; Faculty Member; Faculty Member; School of Medicine; School of Medicine; School of Medicine; School of Medicine; School of Medicine; Koç University Hospital; 11611; 291692; 170966; N/A; 18320Here we report a challenging case of a 52-year-old man presenting with subacute constipation, urinary retention, impotence, absent Achilles reflexes, and hypoesthesia in S2-S5 dermatomes. We review the clinical decision-making as the symptoms evolved and diagnostic testing changed over time. Once the diagnosis is settled, we discuss the sign and symptoms, additional diagnostic tools, treatment options and prognosis.Publication Metadata only A case of chordoma invading multiple neuroaxial bones: report of ten years follow up(Turkish Neurosurgery Society, 2013) Aydın, Ahmet Levent; Sasani, Mehdi; Öktenoğlu, Bekir Tunç; Solaroğlu, İhsan; Özer, Ali Fahir; Faculty Member; Faculty Member; School of Medicine; School of Medicine; 102059; 1022Aim: Chordoma is a rare, slow-growing primary malignant tumor of the axial skeleton, arising from the embryonic cells of primitive notochord. Chordomas may arise at different sites of the vertebral column simultaneously or more probably they may metastasise along the neural axis insidiously. Recurrence despite radical surgery and following adjuvant therapy is possible. MaterIal and Methods: A 46-year-old female patient presented weakness and numbness of the lower extremities. She was operated for clivus chordoma five years ago at another institute. Results: First the patient underwent surgery for resection of the tumor at the cervical region. a second surgery was performed to resect tumor on the foramen magnum and at the C1 level. Histologic examination of the removed vertebra confirmed the diagnosis of chordoma involving the vertebral body. Radiotherapy was administered after the second surgery. Follow-up neurological and radiological examinations revealed no abnormal neurological symptoms 2,5 years after second surgery. There were no distant organ metastases. ConclusIon: A patient with diagnosed chordoma of the spine must be investigated with MRI of other regions of the neuraxis to exclude second or even third source of chordoma metastases. In metastatic chordoma cases, radical or gross total resection should be performed for each lesion but if complete surgical resections are impossible, preoperative or postoperative radiation therapy should be planned to improve life expectancy. / AMAÇ: Kordoma, omurganın ender rastlanan, yavaş ilerleyen malign karakterli bir tümörüdür. Primitif notokordun embryo hücrelerinden köken alır. Omurganın farklı bölgelerinde, birbirinden bağımsız kordoma odakları eş zamanlı olarak gelişmeye başlayabilir. Fakat daha sıklıkla, birinci tümör odağından kaynaklanan metastatik kordoma lezyonları tüm nöral aks boyunca yayılabilir. Radikal cerrahiye ve ek onkolojik tedaviye rağmen rekürens sık görülür. YÖNTEM ve GEREÇLER: Bu sunumda tartışılan 46 yaşındaki kadın hasta, bacaklarında kuvvet ve his kaybı şikayetiyle kliniğimize başvurmuştur. Hasta, beş yıl önce, ayrı bir merkezde klivus kordoması tanısıyla opere edilmiştir. BULGULAR: Hasta öncelikle servikal bölgedeki tümör için opere edilmiştir. İkinci seansta foramen magnum ve C1 seviyesindeki tümör çıkarılmıştır. Patolojik inceleme sonucunda, omurga cismini tutan kordoma lezyonu tanısı konmuştur. İkinci cerrahi seansından sonra hasta radyoterapiye yönlendirilmiştir. Bu tedaviden ikibuçuk yıl sonra yapılan değerlendirmede, hastanın nörolojik muayenesinde progresyon gözlenmemiştir. SONUÇ: Omurganın herhangi bir lokalizasyonunda kordoma tanısı konulan bir hastada, tüm spinal bölge manyetik rezonans görüntüleme (MRG) tetkiki ile incelenmelidir. Bu hastalarda birden fazla kordoma odağına rastlanabilir. Birden fazla odak tespit edilmesi durumunda, her ayrı tümör odağı için rezeksiyon planlanmalıdır. Total rezeksiyonun mümkün olmaması durumunda, yaşam süresini uzatmak için operasyon öncesi ve sonrası dönemlerde radyoterapi uygulanmalıdır.Publication Metadata only A case of pathologic complete response after neoadjuvant triplet chemotherapy for locally advanced colon cancer with mismatch repair enzyme proficiency(Via Medica, 2023) Kocak, Mehmet Zahid; Cakir, Murat; Kerimoglu, Ulku; Araz, Murat; Eryilmaz, Melek Karakurt; Artac, Mehmet; Yumuk, Perran Fulden; School of MedicinePatients with potentially resectable colon cancer and expected to have negative margins should undergo resection rather than neoadjuvant chemotherapy. Recent studies have suggested that neoadjuvant immunotherapy may be an option for tumors with mismatch repair enzyme deficiency (dMMR), but standard treatment for locally advanced colon cancer with mismatch repair enzyme proficiency (pMMR) is still unclear. A 37-year-old male patient was diagnosed with clinical stage IIIC (T4b N1a M0) transverse colon cancer. Mismatch repair proteins were proficient. After 3 cycles of oxaliplatin (85 mg/m(2), day 1), irinotecan (150 mg/m2, IV, day 1), leucovorin (200 mg/m(2), IV, day 1), and 5-fluorouracil (3000 mg/m(2), 46 hours of continuous infusion initiating from day 1), there was a remarkable reduction in the tumoral mass on the abdominal computed tomography. A right hemicolectomy was performed. A pathologic complete response was obtained. Although there is no consensus on which patients are suitable for neoadjuvant therapy in pMMR locally advanced colon cancer, triplet chemotherapy may be a reasonable option in selected patients.Publication Metadata only A case with new-onset neuromyelitis optica spectrum disorder following COVID-19 mRNA BNT162b2 vaccination(Lippincott Williams & Wilkins, 2022) Afşar, Nazire; N/A; N/A; N/A; Çalışkan, İlay; Buluş, Eser; Polat-Altıntaş, Sevgi; Master Student; Doctor; Researcher; N/A; N/A; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); Graduate School of Health Sciences; School of Medicine; N/A; N/A; N/A; 150017Introduction: In the midst of the coronavirus disease of 2019 pandemic, active immunization by effective vaccination gained utmost importance in terms of global health. The messenger RNA (mRNA) vaccines are novel strategies requiring clinical surveillance for adverse events. Case Report: We report a 43-year-old previously healthy female with an optic neuritis attack 24 hours following immunization with the second dose of coronavirus disease of 2019 mRNA BNT162b2 vaccine. A second transverse myelitis attack together with an elevated anti-AQP-4 antibody titer confirmed the diagnosis of neuromyelitis optica spectrum disorder. Conclusion: Our case identifies the BNT162b2 vaccine as a possible trigger for neuromyelitis optica spectrum disorder. This rare and potentially coincidental event has no implications for vaccine administration practices. However, further research is needed to elucidate the effects of mRNA vaccines on humoral and cell-mediated immunity.Publication Metadata only A challenge for peptide coarse graining: transferability of fragment-based models(Wiley-V C H Verlag Gmbh, 2011) Villa, Alessandra; Peter, Christine; N/A; Department of Mechanical Engineering; Engin, Özge; Sayar, Mehmet; Master Student; Faculty Member; Department of Mechanical Engineering; Graduate School of Sciences and Engineering; College of Engineering; N/A; 109820Peptides are highly promising building blocks for design and development of novel materials with potential application areas ranging from drug design to biotechnology. The necessity to understand the structural and thermodynamic properties of these complex materials has led to a dramatic increase in the development of computational techniques geared specifically towards peptide-based systems. Both all-atom (AA) and coarse-grained (CG) simulations of such materials have become extremely important, where the latter is an indispensable tool for reaching the time and length scales relevant to the experiments. Here, we review different approaches and discuss the challenges in the development of CG models for peptides. In particular, we concentrate on the transferability of fragment-based CG models. We analyze the transferability of a solvent-free CG model developed to model hydrophobic phenylalanine dipeptides (FF) in water. Here, we employ the same CG strategy-with non-bonded potentials based on peptide fragments-to two other hydrophobic dipeptides, valine-phenylalanine (VF) and isoleucine-phenylalanine (IF). In line with the previously developed model, the dipeptides are described by seven beads and the potentials developed for FF (bonded and non-bonded) are directly applied to describe the phenylalanine and backbone atoms, while new potentials are developed to account for the valine and isoleucine sidechains. By comparing AA and CG intra and intermolecular samplings, we show the ability of the CG model to reproduce the conformational behavior and thermodynamic association properties of the corresponding atomistic systems.Publication Metadata only A clinical comparison of home-based and hospital-based exercise programs following arthroscopic capsulolabral repair for anterior shoulder instability(Human Kinetics Publ Inc, 2020) Atalar, Ata Can; Eren, Şule Meral; Uçak, Ayla; Çerezci, Önder; N/A; Eren, İlker; Canbulat, Nazan; Demirhan, Mehmet; Faculty Member; Faculty Member; Faculty Member; School of Medicine; School of Medicine; School of Medicine; Koc University Hospital; 168021; 58534; 9882Context: Ideal rehabilitation method following arthroscopic capsulolabral repair surgery for anterior shoulder instability has not been proven yet. Although rapid or slow protocols were compared previously, home- or hospital-based protocols were not questioned before. Objective: The aim of this prospective unrandomized controlled clinical trial is to compare the clinical outcomes of home-based and hospital-based rehabilitation programs following arthroscopic Bankart repair. Design: Non-randomized controlled trial. Setting: Orthopedics and physical therapy units of a single institution. Patients: Fifty-four patients (49 males and 5 females) with an average age of 30.5 (9.1) years, who underwent arthroscopic capsulolabral repair and met the inclusion criteria, with at least 1-year follow-up were allocated into 2 groups: home-based (n = 33) and hospital-based (n = 21) groups. Interventions: Both groups received identical rehabilitation programs. Patients in the home-based group were called for follow-up every 3 weeks. Patients in the hospital-based group admitted for therapy every other day for a total of 6 to 8 weeks. Both groups were followed identically after the eighth week and the rehabilitation program continued for 6 months. Main Outcome Measures: Clinical outcomes were assessed using Disabilities of Arm Shoulder Hand, Constant, and Rowe scores. Mann-Whitney U test was used to compare the results in both groups. Wilcoxon test was used for determining the progress in each group. Results: Groups were age and gender matched (P= .61, P = .69). Average number of treatment sessions was 13.8 (7.3) for patients in the hospital-based group. Preoperative Disabilities of Ann Shoulder Hand (27.46 [11.81] vs 32.53 [16.42], P= .22), Constant (58.23 [14.23] vs 54.17 [10.46], P = .13), and Rowe (51.72 [15.36] vs 43.81 [19.16], P= .12) scores were similar between groups. Postoperative scores at sixth month were significantly improved in each group (P = .001, P = .001, and P = .001). No significant difference was observed between 2 groups regarding clinical scores in any time point. Conclusions: We have, therefore, concluded that a controlled home-based exercise program is as effective as hospital-based rehabilitation following arthroscopic capsulolabral repair for anterior shoulder instability.Publication Metadata only A comparative evaluation of segmental analysis of macular layers in patients with early glaucoma, ocular hypertension, and healthy eyes(2020) Aksoy, F. E.; Altan, C.; Yılmaz, B. S.; Yılmaz, I; Tunç, U.; Kocamaz, M.; Paşaoğlu, I; N/A; Kesim, Cem; Doctor; Koç University Hospital; 387367Purpose: To compare macular layer thicknesses between early glaucoma, ocular hypertension, and healthy eyes and to evaluate the accuracy of spectralis optical coherence tomography (OCT) segmentation software in discriminating early glaucoma from ocular hypertension and healthy eyes. Methods: OCT scans were performed using the standard macular and peripapillary retinal nerve fiber layer (pRNFL) protocols on the Spectralis-OCT. The following macular thickness parameters were compared in the inner and outer circles of the Early Treatment Diabetic Retinopathy Study: total macular thickness (MT), retinal nerve fiber layer (mRNFL), ganglion cell layer (mGCL), inner plexiform layer (mIPL), inner nuclear layer (mINL), outer plexiform layer (mOPL), outer nuclear layer (mONL) and ganglion cell complex (mGCC: sum of mRNFL, mGCL, and mIPL). Sectors and layers with the best area under the receiver operating characteristic curve (AUC) were determined and compared between groups. Results: Of a total of 200 eyes included in this study, 64 eyes had primary open angle glaucoma, 69 had ocular hypertension, and 67 were healthy. Peripapillary RNFL was significantly thinner in the early glaucoma group (P < 0.05). For the macular variables, there was a significant reduction in the MT, mGCC, mRNFL, mGCL, and mIPL thicknesses in the early glaucoma group; while there were no statistically significant differences between the ocular hypertension and control groups (P > 0.05). For distinguishing early glaucoma from normal eyes, AUCs for mGCC, mGCL, and mRNFL were similar to the pRNFL; and for early glaucoma and ocular hypertension, AUCs for mGCC, mGCL mRNF and mIPL were comparable to the pRNFL. Conclusion: Macular segmentation can assist in the early diagnosis of glaucoma as a complementary study to pRNFL analysis.Publication Metadata only A comparative study on thyroid function in alzheimer's disease: results from a Turkish multi-centre study(Journal Neurological Sciences, 2015) Yılmaz, Gökhan; Erbayraktar, Zübeyde; Evlice, Ahmet; Genç, Metin; Aras, Sevgi; Avcı, Aslıhan; Yener, Görsev; Ulusu, Nuriye Nuray; Faculty Member; School of Medicine; 6807Alzheimer's disease is a very severe degenerative disease that affects brain function. Neuronal loss, accumulation of extracellular amyloid beta containing plaques and accumulation of intracellular (tau) neurofibrillary tangles are the hallmarks of this disease. We aim to investigate serum thyroid function tests in Alzheimer's disease, in addition to other dementias, and geriatric Turkish patients. We evaluated patients from Ankara, Dokuz Eylul, Cukurova University Hospitals. 357 female and male geriatric subjects were enrolled. All the cases were selected from three different geographical regions irrespective of sex and socioeconomic status. In this study, we evaluated the results of thyroid functions in Alzheimer disease patients as well as in other dementias and geriatric patients. In patients from Ankara, Central Anatolia region, no significant difference between groups regarding the routine control of biochemical parameters was observed. However, thyroid function results revealed that hypothyroidism in Alzheimer's disease patients from Mediterranean region, Adana and Aegean region, Izmir is a recurrent medical condition and is often an embedded side of the normal aging process. We concluded that currently, routine thyroid functions tests should be a part of all geriatric patients for screening presymptomatic Alzheimer's disease. There might be an interplay between reduced thyroid function and Alzheimer's disease that could be exploited for diagnostic purposes.