PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7645

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Now showing 1 - 10 of 24
  • Data Paper
    Citation - WoS: 2
    Citation - Scopus: 3
    Assessing 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 Tuğçe
    Lighting 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.
  • Article
    Citation - WoS: 11
    Citation - Scopus: 12
    Characterization of the Self-Assembly and Size Dependent Structural Properties of Dietary Mixed Micelles by Molecular Dynamics Simulations
    (Elsevier Ltd., 2019) Tuncer, Esra; Bayramoğlu, Beste
    The bile salts and phospholipids are secreted by the gallbladder to form dietary mixed micelles in which the solvation of poorly absorbed lipophilic drugs and nutraceuticals take place. A comprehensive understanding of the micellization and structure of the mixed micelles are crucial to design effective delivery systems for such substances. In this study, the evolution of the dietary mixed micelle formation under physiologically relevant concentrations and the dependence of structural properties on micelle size were investigated through coarse grained molecular dynamics simulations. The MARTINI force field was used to model cholate and POPC as the representative bile salt and phospholipid, respectively. The micellization behavior was similar under both fasted and fed state concentrations. Total lipids concentration and the micelle size did not affect the internal structure of the micelles. All the micelles were slightly ellipsoidal in shape independent of their size. The extent of deviation from spherical geometry was found to depend on the micellar POPC/cholate ratio. We also found that the surface and core packing density of the micelles increased with micelle size. The former resulted in more perpendicular alignments of cholates with respect to the surface, while the latter resulted in an improved alignment of POPC tails with the radial direction and more uniform core density.
  • Article
    Citation - WoS: 14
    Citation - Scopus: 15
    Biotransformation of Ruscogenins by Cunninghamella Blakesleeana Nrrl 1369 and Neoruscogenin by Endophytic Fungus Neosartorya Hiratsukae
    (Elsevier Ltd., 2018) Özçınar, Özge; Tağ, Özgür; Yusufoğlu, Hasan; Kıvçak, Bijen; Bedir, Erdal
    Biotransformation of steroidal ruscogenins (neoruscogenin and ruscogenin) was carried out with Cunninghamella blakesleeana NRRL 1369 and endophytic fungus Neosartorya hiratsukae yielding mainly P450 monooxygenase products together with a glycosylated compound. Fermentation of ruscogenins (75:25, neoruscogenin-ruscogenin mixture) with C. blakesleeana yielded 8 previously undescribed hydroxylated compounds. Furthermore, microbial transformation of neoruscogenin by endophytic fungus N. hiratsukae afforded three previously undescribed neoruscogenin derivatives. While hydroxylation at C-7, C-12, C-14, C-21 with further oxidation at C-1 and C-7 were observed with C. blakesleeana, N. hiratsukae biotransformation provided C-7 and C-12 hydroxylated compounds along with C-12 oxidized and C-1(O) glycosylated derivatives. The structures of the metabolites were elucidated by 1-D (1H, 13C and DEPT135) and 2-D NMR (COSY, HMBC, HMQC, NOESY, ROESY) as well as HR-MS analyses.
  • Article
    Citation - WoS: 27
    Citation - Scopus: 30
    Biotransformation of Cyclocanthogenol by the Endophytic Fungus Alternaria Eureka 1e1bl1
    (Elsevier Ltd., 2018) Ekiz, Güner; Duman, Seda; Bedir, Erdal
    The microbial transformation of cyclocanthogenol (CCG), Astragalus sp. originated sapogenin, by the endophytic fungus Alternaria eureka 1E1BL1 isolated from Astragalus angustifolius was investigated. Hydroxylation, oxidation, epoxidation, O-methylation, ring-expansion and methyl migration reactions were observed on the triterpenoid skeleton. As a result, eight metabolites were isolated and the structures of the previously undescribed compounds were established by 1-D, 2-D NMR and HR-MS analyses.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 4
    Sensitive and Specific Detection of Ligands Using Engineered Riboswitches
    (Elsevier Ltd., 2018) Morse, Daniel P.; Nevins, Colin E.; Aggrey-Fynn, Joana Efua; Bravo, Rick J.; Pfaeffle, Herman O.I.; Laney, Jess E.
    Riboswitches are RNA elements found in non-coding regions of messenger RNAs that regulate gene expression through a ligand-triggered conformational change. Riboswitches typically bind tightly and specifically to their ligands, so they have the potential to serve as highly effective sensors in vitro. In B. subtilis and other gram-positive bacteria, purine nucleotide synthesis is regulated by riboswitches that bind to guanine. We modified the xpt-pbuX guanine riboswitch for use in a fluorescence quenching assay that allowed us to specifically detect and quantify guanine in vitro. Using this assay, we reproducibly detected as little as 5 nM guanine. We then produced sensors for 2′-deoxyguanosine and cyclic diguanylate (c-diGMP) by appending the P1 stem of the guanine riboswitch to the ligand-binding domains of a 2′-deoxyguanosine riboswitch and a c-diGMP riboswitch. These hybrid sensors could detect 15 nM 2′-deoxyguanosine and 3 nM c-diGMP, respectively. Each sensor retained the ligand specificity of its corresponding natural riboswitch. In order to extend the utility of our approach, we developed a strategy for the in vitro selection of sensors with novel ligand specificity. Here we report a proof-of-principle experiment that demonstrated the feasibility of our selection strategy.
  • Data Paper
    Citation - WoS: 3
    Citation - Scopus: 3
    Small Rna Data Set That Includes Trna-Derived Fragments From Jurkat Cells Treated With Camptothecin
    (Elsevier Ltd., 2018) Coşacak, Mehmet İlyas; Erdoğan, İpek; Nalbant, Ayten; Akgül, Bünyamin
    In this article, we report a small RNA data set obtained from human T cell acute leukemia Jurkat cells, which were treated with the universal apoptotic agent camptothecin. Based on the Annexin-V labeling pattern, we sorted two Jurkat subpopulations in treated cells: one that is sensitive to the drug and the other being relatively more resistant. We report new original data that include the frequency of tRNA-derived fragments (tRF) in drug-sensitive and resistant cells. We also present partially analyzed data to show the origin of reads on tRNAs as well as the borders of the fragments. We believe that this data can benefit the science community working in the field of tRF and/or apoptosis.
  • Article
    Citation - WoS: 1
    Cellular Distribution of Invadopodia Is Regulated by Nanometer Scale Surface Protein Patterns
    (Elsevier Ltd., 2017) Batı Ayaz, Gizem; Can, Ali; Pesen Okvur, Devrim
    Invadopodia are proteolytic structures formed by cancer cells. It is not known whether their cellular distribution can be regulated by the organization of the extracellular matrix or the organization of the golgi complex or whether they have an adhesion requirement. Here, we used electron beam lithography to fabricate fibronectin (FN) nanodots with isotropic and gradient micrometer scale spacings on K-casein and laminin backgrounds. Investigating cancer cells cultured on protein nanopatterns, we showed that (i) presence of FN nanodots on a K-casein background decreased percent of cells with neutral invadopodia polarization compared to FN control surfaces; (ii) presence of a gradient of FN nanodots on a K-casein background increased percent of cells with negative invadopodia polarization compared to FN control surfaces; (iii) polarization of the golgi complex was similar to that of invadopodia in agreement with a spatial link; (iv) local adhesion did not necessarily appear to be a prerequisite for invadopodia formation.
  • Article
    Citation - WoS: 19
    Citation - Scopus: 20
    Specialized Metabolites From the Aerial Parts of Centaurea Polyclada Dc.
    (Elsevier Ltd., 2017) Demir, Serdar; Karaalp, Canan; Bedir, Erdal
    The genus Centaurea L. (Asteraceae) is represented by 200 taxa in the flora of Turkey and several Centaurea species are used as herbal remedies against different conditions. Previous phytochemical investigations on this genus generally revealed the isolation of sesquiterpene lactones and flavonoid derivatives. In our continuous search on Centaurea genus, a phytochemical study was performed on Centaurea polyclada DC., an endemic of West Anatolia. Previously undescribed two sesquiterpene-amino acid conjugates, an elemane and an eudesmane derivative were isolated from the aerial parts of Centaurea polyclada, together with eight known compounds; two elemane derivatives, three flavonoids, a lignan, a phenolic glucoside and a phenylpropanoid glucoside. Structural elucidation of the compounds was based on spectroscopic evidence, including 1D and 2D NMR and high-resolution mass spectrometry, chemical degradation results and reference data comparison. Sesquiterpene-amino acid conjugates are representatives of an unusual group of sesquiterpenes, and elemane-amino acid conjugates are herein reported for the first time in nature.
  • Article
    Citation - WoS: 8
    Citation - Scopus: 9
    Crm1 Inhibitory and Antiproliferative Activities of Novel 4'-alkyl Substituted Klavuzon Derivatives
    (Elsevier Ltd., 2017) Kanbur, Tuğçe; Kara, Murat; Kutluer, Meltem; Şen, Ayhan; Delman, Murat; Alkan, Aylin; Otaş, Hasan Ozan; Akçok, İsmail; Çağır, Ali
    Klavuzons are 6-(naphthalen-1-yl) substituted 5,6-dihydro-2H-pyran-2-one derivatives showing promising antiproliferative activities in variety of cancer cell lines. In this work, racemic syntheses of nine novel 4′-alkyl substituted klavuzon derivatives were completed in eight steps and anticancer properties of these compounds were evaluated. It is found that size of the substituent has dramatic effect over the potency and selectivity of the cytotoxic activity in cancerous and healthy pancreatic cell lines. The size of the substituent can also effect the CRM1 inhibitory properties of klavuzon derivatives. Strong cytotoxic activity and CRM1 inhibition can be observed only when a small substituent present at 4′-position of naphthalen-1-yl group. However, these substituents makes the molecule more cytotoxic in healthy pancreatic cells rather than cancerous pancreatic cells. Among the tested compounds 1,2,3,4-tetrahydrophenanthren-9-yl substituted lactone was the most cytotoxic compound and its antiproliferative activity was also tested in 3D spheroids generated from HuH-7 cell lines.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 7
    High-Speed Dynamic Atomic Force Microscopy by Using a Q-Controlled Cantilever Eigenmode as an Actuator
    (Elsevier Ltd., 2015) Balantekin, Müjdat
    We present a high-speed operating method with feedback to be used in dynamic atomic force microscope (AFM) systems. In this method we do not use an actuator that has to be employed to move the tip or the sample as in conventional AFM setups. Instead, we utilize a Q-controlled eigenmode of an AFM cantilever to perform the function of the actuator. Simulations show that even with an ordinary tapping-mode cantilever, imaging speed can be increased by about 2 orders of magnitude compared to conventional dynamic AFM imaging.