WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
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Article Citation - WoS: 5Citation - Scopus: 7Five New Cardenolides Transformed From Oleandrin and Nerigoside by Alternaria Eureka 1e1bl1 and Phaeosphaeriasp. 1e4cs-1 and Their Cytotoxic Activities(Elsevier Ltd., 2021) Karakoyun, Çiğdem; Küçüksolak, Melis; Bilgi, Eyüp; Doğan, Gamze; Çömlekçi, Yiğit Ege; Bedir, ErdalBiotransformation of oleandrin (1) and nerigoside (2) by endophytic fungi; Alternaria eureka 1E1BL1 and Phaeospheria sp. 1E4CS-1, has led to the isolation of five new metabolites (3, 5, 6, 7 and 8) together with a known compound (4). The structures of the biotransformation products were elucidated by 1D-, 2D NMR and HR-MS. Phaeospheria sp. mainly provided monooxygenation reactions on the A and B rings, whereas A. eureka afforded both monooxygenated and desacetylated derivatives of the substrates. Cytotoxic activity of the compounds was tested against a non-cancerous (HEK-293) and four cancer (PANC-1, MIA PaCa-2, DU 145 and A549) cell lines by MTT cell viability assay. All compounds were less cytotoxic than oleandrin, which had IC50 values ranging between 2.7 and 41.9 nM. Two of the monohydroxylated metabolites, viz. 7(?)-hydroxy oleandrin (3) and 1(?)-hydroxy oleandrin (7), were also potent with IC50 values from 18.45 to 39.0 nM, while desacetylated + monohydroxylated, or dihydroxylated products had much lower cytotoxicity. Additionally, the lesser activity of 2 and its metabolite (6) possessing diginose as sugar residue inferred that oleandrose moiety is important for the toxicity of oleandrin as well as hydrophobicity of the steroid core. © 2020 Phytochemical Society of EuropeArticle Citation - WoS: 3Citation - Scopus: 4Lipid Bilayer on Wrinkled-Interfaced Graphene Field Effect Transistor(Elsevier Ltd., 2021) Özkendir İnanç, Dilce; Çelebi, Cem; Yıldız, Ümit HakanThis study describes lipid bilayer-based sensor interface on SiO2 encapsulated graphene field effect transistors (GFET). The SiO2 layer was utilized as a lipid compatible surface that drives bilayer formation. The two types of surface morphologies i) wrinkled morphology by thermal evaporation (TE) and ii) flat morphology by pulsed electron deposition (PED) were obtained. The sensing performance of wrinkled and flat interfaced-GFETs were investigated, pH sensitivity of wrinkled interfaced-GFETs were found to be ten fold larger than the flat ones. The enhanced sensitivity is attributed to thinning of the oxide layer by formation of wrinkles thereby facilitating electrostatic gating on graphene. We foresee that described wrinkled SiO2 interfaced-GFET holds promise as a cell membrane mimicking sensing platform for novel bioelectronic applications. © 2020Data Paper Citation - WoS: 2Citation - Scopus: 3Assessing Museums' Daylighting Adequacy Without Annual Measurement Campaign: Dataset of a Confrontation Between Measured and Simulated Illuminance Values Inside the Cetacean Gallery of the Charterhouse of Calci(Elsevier Ltd., 2020) Leccese, Francesco; Salvadori, Giacomo; Tambellini, Giuseppe; Kazanasmaz, Zehra TuğçeLighting Cultural Heritage is a complex task: light is necessary for the act of seeing, it can even enhance the visual experience [1,2], in addition proper lighting can significantly cut down energy consumptions [3], but on the same time it has detrimental effects on exhibits, especially daylight. In order to safeguard the exhibits from damages, national and international standards provide specific recommendations for exhibits' exposure, based on their photosensitivity category. These recommendations are the annual luminous exposure(LO) and the Maximum Illuminance Level (E-max), museums' curators have to verify that the display lighting conditions comply with the standards. Historical buildings are often converted into museums but, as their original purpose was different, the lighting conditions are often inadequate (e.g. too much uncontrolled daylight), therefore the lighting conditions' adequacy of the space should be assessed [4]. As the name suggest the annual luminous exposure requires an annual monitoring campaign, unfortunately it often happens that exhibits have been exposed incorrectly for prolonged periods, and therefore it is very important to evaluate the need of a fast intervention. In this casuistry a prolonged measurement campaign is not acceptable. Simulations can help running a great number of analysis while reducing the length and expenses of a measurements campaign, however their previsions must be validated. This paper provides the data acquired through measurements and simulations inside the Cetacean Gallery of the Monumental Charterhouse of Calci, near Pisa (Tuscany Region, Italy). The data comprehends horizontal and vertical illuminance measurements, recorded on December the 6th, and simulations run in Grasshopper with the plugins Honeybee+ and Ladybug. The data are related to the research article entitled "Application of climate-based daylight simulation to assess lighting conditions of space and artworks in historical buildings: the case study of Cetacean Gallery of the Monumental Charterhouse of Calci", published on the Journal of Cultural Heritage [5]. (C) 2020 The Author(s). Published by Elsevier Inc.Conference Object Expression Levels of Ceramide-Metabolising Genes in Newly Diagnosed and Tyrosine Kinase Inhibitor-Resistant Chronic Myeloid Leukemia (cml) Patients: the Discovery of Novel Targets in Cml(Elsevier Ltd., 2014) Yandım, Melis Kartal; Kozanoğlu, İlknur; Özdoğu, Hakan; Pişkin, O.; Özcan, Mehmet Ali; Saydam, Göksel; Baran, Yusuf[No abstract available]Conference Object Inhibition of Jumonji C Domain Containing Histone Demethylases in Acute Myeloid Leukemia(Elsevier Ltd., 2014) Hastar, N.; Koca, D.; Baran, Yusuf[No abstract available]Conference Object Cytotoxic and Cytostatic Effects of Ponatinib on Imatinib-Sensitive And-Resistant Chronic Myeloid Leukemia Cells(Elsevier Ltd., 2014) Yandım, Melis Kartal; Baran, Yusuf[No abstract available]Conference Object Targeting Sphingosine Kinase-1/Spingosine-1-phosphate Receptor 2 Signalling Pathway To Overcome T315i Mutation in 32dcl3 Cells(Elsevier Ltd., 2014) Adan Gökbulut, Aysun; Öğretmen, Besim; Baran, YusufThe main problem in chronic myeloid leukemia patients is the development of resistance against tyrosine kinase inhibitors. The expression of BCR-ABL1 having T315 mutation is responsible for the development of nilotinib resistance. The alterations in sphingolipid signalling pathway is a significant BCR-ABL1-dependent resistance mechanism. Recently, we showed that sphingosine kinase-1 (SK-1)/sphingosine-1 phosphate (S1P)-mediated drug resistance is transduced via sphingosine-1 phosphate receptor 2 (S1P2) that inhibits protein phosphatase 2A (PP2A), causing increased stability of BCR-ABL1. However, specific signaling cascade involved in this process remain unkown. In this study, BCR-ABL1 expressing 32Dcl3 cells, 32D-p210Bcr-Abl(wt) and 32D-p210Bcr-Abl (T315I) were used. The antiproliferative effects of nilotinib, SK-1 inhibitor (PF-543), S1P2 inhibitor (JTE-013), phospholipase C inhibitor (U-73122) and nilotinib/PF-543 and nilotinib/JTE-013 combinations on wt and resistant cells were determined by MTT assay. Isobologram analysis was performed using CompuSyn program.Conference Object Therapeutic Potential of Fisetin, Vitexin and Hesperetin on Chronic Myeloid Leukemia Cells(Elsevier Ltd., 2014) Adan Gökbulut, Aysun; Baran, YusufIn Chronic Myeloid Leukemia (CML) treatment, despite therapeutic efficacy of tyrosine kinase inhibitors, resistance development and side effects cause problems. Fisetin, vitexin and hesperetin are plant-derived flavonoids. In this study, therapeutic potentials of fisetin, vitexin and hesperetin were determined in CML cells. Cytotoxic effects of flavonoids were determined by MTT assay while apoptotic effects were determined by changes in caspase- 3 activity, loss of mitochondrial membrane potential (MMP) and Annexin V/PI double staining. Cytostatic effects of the flavonoids were evaluated by propidium iodide staining using flow cytometry.Conference Object A Novel Biomarker for Drug Resistance in Chronic Myeloid Leukemia: Microrna-17(Elsevier Ltd., 2014) Baran, Yusuf; Fıratlıgil, Burcu; Kartal Yandım, Melis; Kiraz, Yağmur; Kozanoğlu, İlknur; Özdoğu, Hakan; Ünal, AlimiRNAs are single stranded small RNA molecules (20–22 nt), which do not have ability to code for proteins. These types of RNAs play significant roles on gene regulation through inhibition of their target genes. In animals, most of miRNAs show their translational inhibitor effect on target mRNAs by semi-complementation to 3’UTR sequences of mRNAs and deadenylation that cause degradation of these mRNAs. The importance of miRNAs is increasing in cancer diagnosis and treatment since they are one of the major regulators of genes such as oncogenes, tumor suppressor genes. miR-17 is an oncogenic miRNA that suppress the activation of tumor suppressor genes like CDKN1A, p21 and E2F1. Based on previous information, we aimed to determine the correlation between expression levels of miR-17 microRNA in newly diagnosed, tyrosine kinase inhibitors treated and drug resistant CML patients.Conference Object Cytotoxic and Apoptotic Effects of Fisetin, Hesperetin and Vitexinon Acute Promyelocytic Leukemia Cells(Elsevier Ltd., 2014) Adan Gökbulut, Aysun; Baran, YusufAcute Promyelocytic Leukaemia (APL) is characterized by abnormal accumulation of immature granulocytes in the bone marrow and the blood stream. To date, there is no definitive treatment strategy. Fisetin, hesperetin and vitexin are flavanoids found in fruits and vegetables. Their anticancer properties have been studied on several cancer types. In this study, we aimed to examine the cytotoxic, cytostatic and apoptotic effects of fisetin, hesperetin and vitexin on Acute Promyelocytic Leukaemia cells. Cytotoxic effects were evaluated by MTT assay while apoptotic effects of these flavonoids were examined by changes in caspase-3 activity, loss of mitochondrial membrane potential (MMP) and Annexin V/PI double staining. Cytostatic effects of the flavonoids were evaluated by propidium iodide staining using flow cytometry.