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Publication Metadata only 1,2,3-Triazole incorporated coumarin carrying metal-free, Zn(II), Mg(II) phthalocyanines: Synthesis, characterization, theoretical studies, photophysical and photochemical properties(ELSEVIER SCIENCE SA, 2020) YALÇIN, BAHATTİN; Ozdemir, Mucahit; Abliatipova, Aziza; Benian, Sueda; Yalcin, Bahattin; Salan, Umit; Durmus, Mahmut; Bulut, MustafaIn this study, the preparation of two novel phthalonitrile compounds, 7-(propargyloxy)-3-(3,4-dicyanophenoxyphenyl)coumarin (1), and 7-(propargyloxy)-3-(2,3-dicyanophenoxy-phenyl)coumarin (2) were performed. Two new coumarinyl-1,2,3-triazole hybrids, (1-phenethy1-1H41,2,A-triazole 4 yl) 7 methyleneoxy 3 [F. (3,4 dicya nophenoxy)phenyl]-coumarin (3), and (1-phenethy1-1H-[1,2,3]-triazole 4 yl) 7 methyleneoxy 3 [F. (2,3 dicya nophenoxy)phenyl]-coumarin (4), were synthesized by the copper(I)-catalysed Huisgen 1,3-dipolar cycloaddition reaction of 2-(azidoethyl)benzene with terminal ethynyl bearing coumarin derivatives (1 or 2). These novel phthalonitrile derivatives (3 and 4) were converted into their peripheral (5-7) and non-peripheral (8-10) metal-free, zinc(II) and magnesium(II) phthalocyanine counterparts. The synthesized phthalocyanine derivatives are first examples on the phthalocyanine-coumarin derivatives bearing triazole ring. The structures of all these novel compounds were characterized by variety of spectroscopic techniques including FT-IR, UV-vis, H-1 NMR, MALDI-TOF MS and elemental analysis. The photophysicochemical properties of all studied Pcs (5-10) were determined in dimethyl sulfoxide. The zinc(II) and magnesium(II) phthalocyanines bearing triazole containing coumarin substituents appear to be useful as Type II photosensitizers because the singlet oxygen quantum yields ranged in acceptable values from 0.17 to 0.49 confirmed that these phthalocyanines can be suggested as photosensitizers in Photodynamic Therapy applications. Geometry optimization, frequency analysis and molecular orbital energy values of coumarin/triazole substituted phthalocyanine were performed in Density Functional Theory method using the B3LYP/LANL2DZ level of theory.Publication Metadata only 17-HYDROXYLASE DEFICIENCY: RARE CAUSE OF DELAYED PUBERTY(KARGER, 2017) Guven, Ayla; Guran, Tulay; Krone, NilsPublication Metadata only 17OH-PREGNENOLONE SEEMS A MAJOR DRIVE OF ANDROGEN EXCESS IN PATIENTS WITH 11 beta-HYDROXYLASE DEFICIENCY(KARGER, 2017) Yildiz, Melek; Turan, Serap; Akcay, Teoman; Atay, Zeynep; Onal, Hasan; Baris, Tugba; Haklar, Goncagul; Bereket, Abdullah; Guran, TulayPublication Metadata only 2-Thiobarbituric acid addition improves structural integrity and controlled drug delivery of biocompatible pectin hydrogels(TAYLOR & FRANCIS AS, 2021) BATIREL, SAİME; Guner, O. Z.; Kocaaga, B.; Batirel, S.; Kurkcuoglu, O.; Guner, F. S.Thiolated polymers are commonly preferred for biomedical applications with their good permeation properties providing them higher bioavailability. However, the thiolation process is mostly time-consuming series of chemical reactions. This study describes a simple irreversible thiol group integration to the pectin hydrogels by noncovalent bonding. We used 2-thiobarbituric acid (TBA) for thiolation. We proved with full-atom molecular dynamics simulations and experimental methods that TBA desertion is negligible. Pectin hydrogels become more flexible and their disintegration is delayed from 4 h up to four days with TBA addition. Also, hydrogels can successfully deliver the model drug, theophylline, showing a controlled release profile.Publication Metadata only 25OH VITAMIN D LEVELS IN REFERENCE HOSPITAL LABORATORIES FROM TURKEY: A MULTICENTER NATIONWIDE STUDY(SPRINGER LONDON LTD, 2019) Yavuz, D. Gogas; Ersoy, R.; Bilen, H.; Canturk, Z.; Altuntas, Y.; Turvida, S. G.Publication Metadata only 3-Pyridinylboronic acid normalizes the effects of 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine exposure in zebrafish embryos(TAYLOR & FRANCIS LTD) ALTURFAN, EBRU IŞIK; Ustundag, Fumet Duygu; Unal, Ismail; Cansiz, Derya; Ustundag, Unsal Veli; Subasat, Hulya Kara; Alturfan, A. Ata; Tiber, Pinar Mega; Emekli-Alturfan, Ebru1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is a neurotoxin that damages dopaminergic neurons. Zebrafish has been shown to be a suitable model organism to investigate the molecular pathways in the pathogenesis of Parkinson's disease and also for potential therapeutic agent research. Boron has been shown to play an important role in the neural activity of the brain. Boronic acids are used in combinatorial approaches in drug design and discovery. The effect of 3-pyridinylboronic acid which is an important sub-class of heterocyclic boronic acids has not been evaluated in case of MPTP exposure in zebrafish embryos. Accordingly, this study was designed to investigate the effects of 3-pyridinylboronic acid on MPTP exposed zebrafish embryos focusing on the molecular pathways related to neurodegeneration and apoptosis by RT-PCR. Zebrafish embryos were exposed to MPTP (800 mu M); MPTP + Low Dose 3-Pyridinylboronic acid (50 mu M) (MPTP + LB) and MPTP + High Dose 3-Pyridinylboronic acid (100 mu M) (MPTP + HB) in well plates for 72 hours post fertilization. Results of our study showed that MPTP induced a P53 dependent and Bax mediated apoptosis in zebrafish embryos and 3-pyridinylboronic acid restored the locomotor activity and gene expressions related to mitochondrial dysfunction and oxidative stress due to the deleterious effects of MPTP, in a dose-dependent manner.Publication Open Access 3D Propolis-Sodium Alginate Scaffolds: Influence on Structural Parameters, Release Mechanisms, Cell Cytotoxicity and Antibacterial Activity(MDPI, 2020-11-02) AKSU, MEHMET BURAK; Aranci, Kubra; Uzun, Muhammet; Su, Sena; Cesur, Sumeyye; Ulag, Songul; Amin, Al; Guncu, Mehmet Mucahit; Aksu, Burak; Kolayli, Sevgi; Ustundag, Cem Bulent; Silva, Jorge Carvalho; Ficai, Denisa; Ficai, Anton; Gunduz, OguzhanIn this study, the main aim was to fabricate propolis (Ps)-containing wound dressing patches using 3D printing technology. Different combinations and structures of propolis (Ps)-incorporated sodium alginate (SA) scaffolds were developed. The morphological studies showed that the porosity of developed scaffolds was optimized when 20% (v/v) of Ps was added to the solution. The pore sizes decreased by increasing Ps concentration up to a certain level due to its adhesive properties. The mechanical, swelling-degradation (weight loss) behaviors, and Ps release kinetics were highlighted for the scaffold stability. An antimicrobial assay was employed to test and screen antimicrobial behavior of Ps against Escherichia coli and Staphylococcus aureus strains. The results show that the Ps-added scaffolds have an excellent antibacterial activity because of Ps compounds. An in vitro cytotoxicity test was also applied on the scaffold by using the extract method on the human dermal fibroblasts (HFFF2) cell line. The 3D-printed SA-Ps scaffolds are very useful structures for wound dressing applications.Publication Metadata only 40 Hz auditory steady-state response in eleven subjects with false hearing loss(WILEY, 2020) ATILGAN, ATILIM; Yuksel, Mustafa; Atilgan, Atilim; Derinsu, UfukPublication Metadata only A 46, XX patient with 21-OHD diagnosed during the etiologic workup of male infertility(KARGER, 2019) Bugrul, Fuat; Yildirak, Ekrem; Guran, TulayPublication Metadata only A broad range of symptoms in allgrove syndrome: single center experience in Southeast Anatolia(SPRINGER, 2020) GÜRAN, TÜLAY; Polat, R.; Ustyol, A.; Tuncez, E.; Guran, T.Background Allgrove syndrome (OMIM 231550) is a rare autosomal recessive disease characterized by non-CAH primary adrenal insufficiency (non-CAH PAI), alacrima, and achalasia. It is caused by mutations in the AAAS gene. The syndrome is also associated with variable progressive neurological impairment and dermatological abnormalities. Methods and results We diagnosed 23 patients from 14 families with Allgrove syndrome, based on the presence of at least two characteristic symptoms, usually adrenal insufficiency and alacrima, between 2008 and 2018. A previously described nonsense variant of AAAS was detected in 19 patients from 12 families at homozygous state. Another novel homozygous mutation (c.394-397delCTGT) in AAAS was detected in four patients from two families. Presenting symptoms were alacrima (23/23; 100%), adrenal insufficiency (18/23; 78%), achalasia (13/23; 57%), short stature/growth retardation (16/23; 70%), hyperreflexia (15/23; 65%), palmoplantar hyperkeratosis (13/23; 57%), hyperpigmentation of the skin (10/23; 43%), hypoglycemia-induced convulsion (7/23; 30%), swallowing difficulty and vomiting (6/23; 26%). Serum DHEAS concentrations were low in all patients (23/23; 100%). Conclusions Clinical symptoms vary even among patients carrying the same mutation. Triple A syndrome should be considered in the etiology of non-CAH PAI in Arab populations and in Southeast Turkey. Any child with non-CAH PAI should be evaluated for the presence of alacrima and/or achalasia or family history of alacrima and/or achalasia. Children with alacrima and/or achalasia should also be investigated for adrenal insufficiency. Definitive molecular diagnosis is essential for early diagnosis and management of adrenal insufficiency, neurological symptoms, and growth retardation in patients and early diagnosis of as yet asymptomatic cases in the family, together with genetic counseling.Publication Metadata only A Case Of Syndromic Hypopituitarism(KARGER, 2019) Kaygusuz, Sare Betul; Ates, Esra Arslan; Kirkgoz, Tarik; Eltan, Mehmet; Abali, Zehra Yavas; Helvacioglu, Didem; Menevse, Tuba Seven; Tosun, Busra Gurpinar; Tutar, Engin; Volkan, Burcu; Tuney, Davut; Turan, Serap; Bereket, Abdullah; Guran, TulayPublication Open Access A case report: Successful treatment of influenza B associated acute necrotizing encephalopathy in an adult using combination of high dose oseltamivir-ivig-pulse metylprednisolone(ELSEVIER, 2019-10) TUNCER, EMİNE NEŞE; Erdil, E.; Vural, E.; Koytak, P. Kahraman; Tuncer, E. N.Publication Metadata only A case series of 3 primitive myxoid mesenchimal tumour of infancy, including one case with brain metastasis; histopathologic, immunohistochemical and molecular investigation(SPRINGER, 2019) Kutlu, I.; Turkoz, H. K.; Celkan, T.; Ozel, S. Cinar; Comunoglu, N.Publication Metadata only A city-wide survey of dental students' opinions on undergraduate oral surgery teaching(WILEY, 2020) GÖNÜL, ONUR; Burdurlu, Muammer Cagri; Cabbar, Fatih; Dagasan, Volkan; Cukurova, Zeynep Gulen; Doganay, Ozge; Yalcin Ulker, Gul Merve; Atalay, Berkem; Gonul, Onur; Ozcakir Tomruk, CeydaPurpose This study aimed to carry out a city-wide survey to evaluate undergraduate students' opinions on their oral surgery training by measuring their self-confidence. Materials and Methods A cross-sectional survey of 383 3rd year, 412 4th year and 363 5th year undergraduate dental students from six dental schools in Istanbul with a mean age of 22.73 +/- 1.55 was conducted towards the end of the academic year. A web link to the questionnaire was sent to the contact person at the participating dental schools. The questionnaires were anonymously evaluated. Descriptive statistics were calculated, and Chi-square tests were performed to examine the data. A P-value of In total, 1158 responses were returned, representing 67% of the overall students in the 2018-2019 academic year. The male respondents were significantly more self-confident than females in the general aspects of surgical skills. More than half of the respondents (53%) felt confident in oral surgery knowledge to undertake independent practice. Although 5th year respondents felt more confident in the general aspect of the questionnaire, their ability of differentiation of odontogenic and non-odontogenic pain was lower than their counterparts. The majority (86%) of the participants disagreed that the only knowledge required for oral surgery was that of tooth and jaw anatomy. Conclusion This survey revealed perceived confidence in tooth and retained root extraction. The male respondents were found to be more self-confident. There is a need for improvement in surgical skills, recognition of malignancies and differentiation of the origin of the pain.Publication Open Access A comparative exploration of the phytochemical profiles and bio-pharmaceutical potential of Helichrysum stoechas subsp. barrelieri extracts obtained via five extraction techniques(ELSEVIER SCI LTD, 2020-04) EMRE, GİZEM; Zengin, Gokhan; Cvetanovic, Aleksandra; Gasic, Uros; Tesic, Zivoslav; Stupar, Alena; Bulut, Gizem; Sinan, Kouadio Ibrahime; Uysal, Sengul; Picot-Allain, Marie Carene Nancy; Mahomoodally, Mohamad FawziWe endeavoured to probe into and compare the possible effect(s) of different extraction techniques (accelerated solvent extraction (ASE), microwave-assisted extraction (MAE), ultrasonication-assisted extraction (UAE), maceration, and Soxhlet extraction (SE)) on the bioactivity (antioxidant and enzyme inhibitory activities) of the aerial parts of Helichrysum stoechas subsp. barrelieri (Ten.) Nyman. Total phenolic and flavonoid contents of the extracts obtained by different extraction methods followed the order of ASE > MAE > UAE > maceration > SE. Extract obtained by ASE was the most potent radical scavenger (219.92 and 313.12 mg Trolox equivalent [FE]/g, against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), respectively) and reducing agent (927.39 and 662.87 mg TE/g, for cupric reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP), respectively). Helichrysum stoechas extract obtained by UAE (18.67 mg ethylenediaminetetraacetic equivalent [EDTAE]/g) was the most active metal chelator and inhibitor of acetylcholinesterase (4.23 mg galantamine equivalent [GALAE]/g) and butyrylcholinesterase (6.05 mg GALAE/g) cholinesterase. Extract from maceration (183.32 mg kojic acid equivalent [KAE]/g) was most active against tyrosinase while ASE extract (1.66 mmol acarbose equivalent [ACAE]/g) effectively inhibited alpha-glucosidase. In conclusion, data amassed herein tend to advocate for the use of non-conventional extraction techniques, namely ASE and UAE, for the extraction of bioactive secondary metabolites from H. stoechas aerial parts.Publication Metadata only A comparison of flood cooling, minimum quantity lubrication and high pressure coolant on machining and surface integrity of titanium Ti-5553 alloy(ELSEVIER SCI LTD, 2018) KAYNAK, YUSUF; Kaynak, Yusuf; Gharibi, Armin; Yilmaz, Umit; Koklu, Ugur; Aslantas, KubilayTi-5553 alloy is considered as a next generation aerospace alloy, however, it is also considered as difficult-to machine material due to its thermal and mechanical properties. As limited research work presented in literature on machining process of this alloy, more research is needed to determine appropriate machining strategies for this alloy. Thus, this study presents extensive experimental work to asses the machining performance of this next generation aerospace alloy in a wide range of cutting speeds by utilizing high pressure coolant (HPC) delivery, minimum quantity lubrication (MQL), and flood cooling. Machining performance measures are tool wear rate, force components, and chip breaking. Surface and subsurface characteristics of machined parts were evaluated focusing on surface topography, dimensional accuracy, microhardness and XRD analysis. The obtained results showed that high pressure coolant delivery remarkable improved machining performance of this alloy at higher cutting speeds as compared to flood cooling and MQL. Considering surface integrity characteristics, surface and subsurface hardness shows decreased trend in all conditions and cutting speeds as compared to hardness of as received material resulting from thermal softening. XRD analysis illustrated that alfa and beta peaks shows noticeable broadening and reduced intensity but no phase transformation is observed.Publication Metadata only A DEMATEL Integrated Interval Valued Intuitionistic Fuzzy PROMETHEE Approach for Parking Lots Evaluation(OLD CITY PUBLISHING INC, 2018) Sennaroglu, Bahar; Yilmazer, Kadriye Busra; Tuzkaya, Gulfem; Tuzkaya, Umut RifatHigh population density of Istanbul results with the scarcity of parking spaces. Authorities are planning to construct various parking lots in Istanbul to satisfy increasing car park requirement. To find convenient locations and construct well-designed parking lots, current ones should be evaluated firstly. In this study, a special version of parking lots, Park&Ride (P&R) facilities, are studied considering the need to support public transport usage. Randomly chosen P&R lots in Istanbul are compared according to the literature based criteria by using interval-valued intuitionistic fuzzy Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE). However, the number of evaluation criteria for P&R lots are large and firstly some of them are eliminated by using Decision-Making Trial and Evaluation Laboratory (DEMATEL) technique. The case study verifies the effectiveness of the proposed methodology. Also, results are analyzed for different importance degrees of criteria.Publication Metadata only A developmental study of glutamatergic neuron populations in the ventrobasal and the lateral geniculate nucleus of the thalamus: Comparing Genetic Absence Rats from Strasbourg (GAERS) and normal control wistar rats(PERGAMON-ELSEVIER SCIENCE LTD, 2017) ONAT, FİLİZ; Kirazhi, Ozlem; Caydar, Safiye; Yildizel, Sercan; Onat, Filiz; Kaptanoglu, ErkanAn imbalance of GABAergic inhibition and glutamatergic excitation is suspected to be the cause of absence epileptic seizures. Absence seizures are known to be generated in thalamocortical circuitry. In the present study we used light microscopy immunohistochemistry to quantify the density of glutamate+ve neurons at two developmental stages (P10 and P60) in two thalamic nuclei, the ventrobasal (VB) and lateral geniculate nucleus (LGN) in Wistar rats and compared the results with similar data obtained from genetic absence epilepsy rats from Strasbourg (GAERS). Rats were perfused transcardially with glutaraldehyde and paraformaldehyde fixative, then samples from VB and LGN were removed from each animal and sectioned. The glutamatergic neurons were labelled using light-microscopic glutamate immunohistochemistry. The disector method was used to quantify the glutamate+ve neurons in VB and LGN of GAERS and Wistar rats. The data were statistically analyzed. The distribution of the glutamate+ve neurons in the VB thalamic nucleus showed a significant reduction in the neuronal profiles per unit thalamic area from P10 to P60 in both Wistar and GAERS. The decrease was greater in the GAERS compared to the Wistar animals. However, in the LGN no reduction was observed either in the Wistar or in the GAERS. Comparing the density of glutamate+ve neurons in the VB thalamic nucleus of P10 of Wistar animals with of P10 GAERS showed statistically significant greater densities of these neurons in GAERS than in the Wistar rats. However no significant difference was present at P60 between the Wistar and GAERS animals. The disproportional decrease in GAERS may be related to the onset of absence seizures or may be related to neurogenesis of absence epilepsy. (C) 2016 ISDN. Published by Elsevier Ltd. All rights reserved.Publication Metadata only A double auction based mathematical market model and heuristics for internet-based secondhand durable good markets(PERGAMON-ELSEVIER SCIENCE LTD, 2019) ÖZER, ALİ HAYDAR; Ozer, Ali HaydarTrading of used goods in secondhand markets is considered to have both environmental and economic benefits. For the trading of used goods as well as new ones, this study proposes a periodic double auction model for Internet-based electronic markets whereby each bidder can place both asks and bids for selling and purchasing goods respectively during a trading period. The proposed model allows each bidder to place a spending limit order such that the difference between the cost of the purchased goods and the income obtained from the sold goods does not exceed this limit. Furthermore, since a bidder may be indifferent to multiple goods, e.g. copies of a same title, the model also provides a mechanism so that bidders may combine a number of bids inside a set and put a limit on the number of goods to be purchased in this set. The model is mathematically defined, and the corresponding winner determination problem is formulated using linear integer programming. Since the problem is shown to be NP-hard, a number of heuristic methods are also proposed. Performances of these methods are evaluated on a comprehensive test suite and statistical analyses of the results are presented. Furthermore, possible economical contribution of the model is also evaluated. The results indicate that the proposed model can be used efficiently in large-scale markets with tens of thousands of bidders. (C) 2019 Elsevier Ltd. All rights reserved.Publication Metadata only A European Survey to Identify New Roads for Care, Training and Research Around Rare Metabolic Bone Diseases(KARGER, 2016) Fernandez, Isabelle; Ahmed, Syed Faisal; Bishop, Nick; Brandi, Maria Luisa; Doulgeraki, Artemis; Haeusler, Gabriele; Hogler, Wolfgang; Kostik, Mikhail; Makitie, Outi; Moreno, Gabriel Martos; Nilsson, Ola; Schnabel, Dirk; Sumnik, Zdenek; Tillmann, Vallo; Turan, Serap; Zillikens, Carola; Linglart, Agnes