Demircan, Y.
Erdem, Murat
Ozgur, E.
Gündüz, Ufuk
Külah, Haluk
In this study, 3D-electrode contactless dielectrophoresis (DEP) system is utilized to drive a relationship between the drug resistance level and dielectrophoretic response of doxorubicin resistant K562 (K562/dox) cells. The number of trapped cells, stained fluorescently, is ascertained by measuring the light intensity with Image J. For accurate counting of cells through intensity analysis, an algorithm was developed, which exploits cell transparency. K562/dox cells resistant to 100, 300, 500 and 1000 nM doxorubicin are used for the analysis. A significant increase in trapped cell number is observed up to 300 nM. However, further increase in drug resistance level is not reflected in DEP response, considerably.


Investigation of the role of programmed cell death 10 (PDCD10) protein in multidrug resistance
Urfalı Mamatoğlu, Çağrı; Gündüz, Ufuk; Department of Biology (2018)
Drug resistance, a major obstacle in chemotherapy, is the sum of several cellular alterations including resistance to induction of apoptosis. Apoptosis is a well-regulated cell death mechanism which is controlled by several signaling pathways and a vast number of proteins. Alterations in the proteins involved in the apoptotic regulation have been associated with drug resistance in cancer. Programmed Cell Death 10 (PDCD10) protein is a novel apoptotic regulator that is recently linked to the modulation of ce...
Assessment of effects of multi drug resistance on dielectric properties of K562 leukemic cells using electrorotation
Bahrieh, Garsha; Erdem, Murat; Ozgur, Ebru; Gündüz, Ufuk; Külah, Haluk (2014-01-01)
In this study, dielectric characterization of multidrug resistant (MDR) K562 human leukemia cells was carried out using a MEMS based electrorotation (ER) device with 3D electrodes. P-glycoprotein (P-gp) dependent MDR causes variation in cell dielectric properties (cell interior conductivity (sigma(i)), membrane capacitance (C-m) and total effective membrane conductance (G(m)*)) due to overexpression of P-gp, which modulates the activity of membrane-bound Cl- channels. Different cell populations resistant to...
Prediction of multiphase flow properties from nuclear magnetic resonance imaging
Karaman, Türker; Akın, Serhat; Department of Petroleum and Natural Gas Engineering (2009)
In this study a hybrid Pore Network (PN) model that simulates two-phase (water-oil) drainage and imbibition mechanisms is developed. The developed model produces Nuclear Magnetic Resonance (NMR) T2 relaxation times using correlations available in the literature. The developed PN was calibrated using experimental relative permeability data obtained for Berea Sandstone, Kuzey Marmara Limestone, Yeniköy Dolostone and Dolomitic Limestone core plugs. Pore network body and throat parameters were obtained from ser...
Prediction of the effects of single amino acid variations on protein functionality with structural and annotation centric modeling
Cankara, Fatma; Tunçbağ, Nurcan; Department of Bioinformatics (2020)
Whole-genome and exome sequencing studies have indicated that genomic variations may cause deleterious effects on protein functionality via various mechanisms. Single nucleotide variations that alter the protein sequence, and thus, the structure and the function, namely non-synonymous SNPs (nsSNP), are associated with many genetic diseases in human. The current rate of manually annotating the reported nsSNPs cannot catch up with the rate of producing new sequencing data. To aid this process, automated compu...
Engineering of alcohol dehydrogenase 2 hybrid-promoter architectures in Pichia pastoris to enhance recombinant protein expression on ethanol
Ergun, Burcu Gunduz; Gasser, Brigitte; Mattanovich, Diethard; Çalık, Pınar (2019-07-09)
The aim of this work is to increase recombinant protein expression in Pichia pastoris over the ethanol utilization pathway under novel-engineered promoter variants (NEPVs) of alcohol dehydrogenase 2 promoter (P-ADH2) through the generation of novel regulatory circuits. The NEPVs were designed by engineering of transcription factor binding sites (TFBSs) determined by in silico analyses and manual curation systematically, by (a) single-handedly replacement of specified TFBSs with synthetic motifs for Mxr1, Ca...
Citation Formats
Y. Demircan, M. Erdem, E. Ozgur, U. Gündüz, and H. Külah, “DETERMINATION OF MULTIDRUG RESISTANCE LEVEL IN K562 LEUKEMIA CELLS BY 3D-ELECTRODE CONTACTLESS DIELECTROPHORESIS,” 2014, Accessed: 00, 2020. [Online]. Available: