Molecular Biology and Genetics / Moleküler Biyoloji ve Genetik
Permanent URI for this collectionhttps://hdl.handle.net/11147/9
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Article Blank Frame and Intensity Variation Distortion Detection and Restoration Pipeline for Phase-Contrast Microscopy Time-Lapse Images(Aves, 2024) Ucar, Mahmut; Iheme, Leonardo O.; Onal, Sevgi; Pesen-Okvur, Devrim; Yalcin-Ozuysal, Ozden; Toreyin, Behcet U.; Unay, DevrimIn this study, we propose a preprocessing pipeline for the detection and correction of distorted frames in time-lapse images obtained from phase-contrast microscopy. The proposed pipeline employs the average intensities of frames as a foundational element for the analysis. In order to evaluate the degree of correction required for intensity variance, a normalization technique is applied to the difference between the average intensity of a specific frame and the median average intensity of all frames within the study. Our restoration method increases the histogram similarity between the distorted and non-distorted frames, preserves trans-passing pixels in regions of interest, and mitigates the development of additional distortions. The efficacy of the proposed method was evaluated using 15 395 time-lapse image frames from 27 experiments using our own dataset and 830 time-lapse images from four different experiments obtained from the cell tracking challenge. The results of the validation demonstrate a high degree of numerical and visual accuracy of the proposed pipeline.Article Epithelial-Mesenchymal Transition as a Potential Route for Dapt Resistance in Breast Cancer Cells(Walter de Gruyter GmbH, 2023) Tellı, Kubra; Ozuysal, Ozden Yalcın; Telli, Kübra; Yalçın Özuysal, ÖzdenObjectives: Notch is a conserved pathway involved in cell- fate determination and homeostasis. Its dysregulation plays a role in poor prognosis and drug resistance in breast cancer. Targeting Notch signaling via inhibition of the gamma- secretase complex is in the spotlight of modern cancer treat- ments. Gamma-secretase inhibitors (GSI) have shown suc- cessful clinical activity in treating cancers, yet the possible resistance mechanism remains unstudied. Modeling the resistance and understanding culprit molecular mechanisms can improve GSI therapies. Accordingly, the aim of this study is to generate and analyze GSI-resistant breast cancer cells. Methods: Gradually increasing doses of DAPT, a well-known GSI, were applied to MCF-7 breast cancer cell lines to generate resistance. Cell viability, migration and gene expressions were assessed by MTT, wound healing and qRT-PCR analyses. Results: DAPT-resistant MCF-7 cells exhibited abnormal expression of Notch receptors, Notch targets (HES1, HES5, HEY1), and epithelial-mesenchymal transition (EMT) markers (E-cadherin, ZO-1, SNAIL2, N-cadherin) to overcome the continuous increase in DAPT toxicity by increased migration through mesenchymal transition. Conclusions: This study prospects into the role of EMT in the potential resistance mechanism against DAPT treatment for breast cancer cells. Complementary targeting of EMT should be investigated further for a possible effect to potentiate DAPT’s anti-cancer effects.Article Citation - WoS: 4Citation - Scopus: 4Protocol for Cell Surface Biotinylation of Magnetic Labeled and Captured Human Peripheral Blood Mononuclear Cells(Elsevier, 2022) Ayaz Güner, Şerife; Acar, Mustafa Burak; Boyvat, Dudu; Güner, Hüseyin; Bozalan, Habibe; Güzel, Melis; Yıldır, Selin Kübra; Altınsoy, Nilay; Fındık, Fatma; Karakükçü, Musa; Özcan, ServetAnalysis of the surfaceome of a blood cell subset requires cell sorting, followed by surface protein enrichment. Here, we present a protocol combining magnetically activated cell sorting (MACS) and surface biotinylation of the target cell subset from human peripheral blood mononuclear cells (PBMCs). We describe the steps for isolating target cells and their in-column surface biotinylation, followed by isolation and mass spectrometry analysis of biotinylated proteins. The protocol enables in-column surface biotinylation of specific cell subsets with minimal membrane disruption.Article Comparative Proteome Profiles of Methicillin-Resistant Staphylococcus Aureus in Response To Vanillic Acid and 2-Hydroxycinnamic Acid(Bentham Science Publishers, 2021) Keman, Deniz; Soyer, FerdaBackground: The ability of Staphylococcus aureus to cause severe infections and the difficulty of the treatments due to the multiple antibiotic resistance make this bacterium a lifethreatening human pathogen. This situation necessitates the exploration of novel antimicrobial compounds with known targets on bacteria. Phenolic acids naturally produced in plants as secondary metabolites are good candidates for being alternative antimicrobials for antibiotic-resistant bacteria. Objective: Investigation of protein profile of Methicillin-Resistant S. Aureus (MRSA) in the presence of subinhibitory concentrations of phenolic acids. Methods: MRSA was subjected to subinhibitory concentrations of Vanillic Acid (VA) and 2-Hydroxycinnamic Acid (2-HCA), separately, and the proteomic analyses were carried out by using liquid chromatography coupled to mass spectrometry. Results: Both phenolic acids elicited identification of differently expressed proteins that have roles in DNA replication, repair, RNA processing and transcription, protein synthesis, maintenance of cell homeostasis, several metabolic reactions in energy, carbohydrate and lipid metabolisms and also proteins related with the virulence and the pathogenicity of MRSA when compared with the control group. The numbers of the proteins identified were 444, 375, and 426 for control, VA-treated MRSA, and 2-HCA-treated MRSA, respectively, from which 256 were shared. While VA treatment resulted in 149 unidentified MRSA proteins produced in control, 2-HCA treatment resulted in 126 unidentified proteins. Data are available via ProteomeXchange with identifier PXD016922. Conclusion: The results obtained from this study might indicate the potential targets on bacteria and the effective use of phenolic acids in the battle with antibiotic-resistant pathogens.Article Citation - WoS: 2Citation - Scopus: 2Antiviral Microrna Expression Signatures Are Altered in Subacute Sclerosing Panencephalitis(Wolters Kluwer Medknow Publications, 2021) Tüfekçi, Kemal Uğur; Allmer, Jens; Çarman, Kürşat Bora; Bayram, Erhan; Topçu, Yasemin; Hız, Semra; Genç, Şermin; Yiş, UluçBackground: Subacute sclerosing panencephalitis (SSPE) is a chronic, progressive disease caused by a persistent infection of the measles virus. Despite extensive efforts, the exact neurodegeneration mechanism in SSPE remains unknown. MicroRNAs (miRNAs) have emerged as an essential part of cellular antiviral defense mechanisms and can be modulated by antiviral cytokines Such as interferon-beta (IFN-beta). Aims and Objectives: In this study, we aimed to elucidate the role of antiviral miRNAs in the pathogenesis of SSPE and analyze the interaction between host antiviral miRNAs and virus genes. Materials and Methods: Thirty-seven patients who were followed with SSPE and age-matched healthy children were included in the study. Peripheral blood mononuclear cell levels of miR-196b, miR-296, miR-431, and miR-448 were analyzed using quantitative polymerase chain reaction. Target predictions and pathway constructions of deregulated miRNAs were assessed. Results: Here, we showed that IFN-beta-modulated miR-196b, miR-296, and miR-431 were significantly upregulated in patients with SSPE compared with healthy controls. Besides, sequence complementarity analysis showed that miR-296 and miR-196b predicted binding regions in measles virus genomic RNA. Conclusion: Our findings suggest that antiviral miRNAs are upregulated in patients with SSPE, which could be a part of the host antiviral defense mechanism. </p>Article Citation - WoS: 15Citation - Scopus: 16The Usability of Juniperus Virginiana L. as a Biomonitor of Heavy Metal Pollution in Bishkek City, Kyrgyzstan(Taylor & Francis, 2015) Kurmanbekova, Gülbübü; Severoğlu, Zeki; Özyiğit, İbrahim İlker; Doğan, İlhan; Demir, Göksel; Yalçın, İbrahim Ertuğrul; Kaşoğlu, GültenUncontrolled and unplanned urbanization and industrialization due to increase of population and rapid industrial development have created severe environmental problems in Kyrgyzstan during the last few decades. In this study, Juniperus virginiana, a dioecious species, was employed in order to make assessment of the heavy metal pollution rate in the area and of the heavy metal pollution impact on the mineral nutrient status of the plant. For this study, leaf (washed and unwashed) and bark samples of J. virginiana, and its co-located soil samples were collected from eight different stations, all in the capital of Kyrgyzstan, Bishkek, in 2012 vegetation period. The standard procedures were used and the determinations of heavy metal and nutrient element contents (Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Pb and Zn) in all samples were done using inductively coupled plasma-optical emission spectroscopy. According to our measurements, J. virginiana was found to be capable of accumulating a considerable amount of metals and the mineral nutrient uptake pattern was altered because of metal deposition in the plant, which showed a contamination risk in the area.Article Citation - WoS: 20Citation - Scopus: 19Using the Turkish Red Pine Tree To Monitor Heavy Metal Pollution(HARD, 2020) Yalçın, Ertuğrul; Özyiğit, İbrahim İlker; Doğan, İlhan; Demir, Göksel; Yarcı, CelalTurkish red pine is an evergreen tree species widely distributed in the Aegean and Mediterranean regions in Turkey. In the present work, the heavy metal pollution level in Istanbul was investigated using Turkish red pine as a biomonitor. For determining heavy metal concentrations (Cd, Co, Cr, Mn, Ni and Pb) in leaf (unwashed and washed) and bark samples of Turkish red pine and its co-located soil samples we used ICP-OES. Additionally, particulate matter profiles of the research areas were investigated. The samples were collected from 5 different localities: 4 from the Bosporus region (Yildiz Grove, Fethi Pasha Grove, Baltalimani Grove and Mihrabad Grove) and one from Prince Island, also known as Buyukada (as control). According to our measurements, the highest heavy metal accumulations (in mg kg(-1) DW) in plant part samples were measured between 1.526 +/- 0.012 and 1.639 +/- 0.015 for Cd, 0.543 +/- 0.007 and 0.600 +/- 0.009 for Co, 5.110 +/- 0.064 and 5.648 +/- 0.072 for Cr, 9.347 +/- 0.105 and 10.331 +/- 0.111 for Mn, 7.483 +/- 0.091 and 8.271 +/- 0.096 for Ni, and 13.848 +/- 0.159 and 14.950 +/- 0.167 for Pb, while the highest heavy metal accumulations (in mg kg(-1) DW) in soil samples were measured between 1.813 +/- 0.021 and 1.974 +/- 0.029 for Cd, 6.326 +/- 0.082 and 6.992 +/- 0.091 for Co, 22.017 +/- 0.284 and 23.685 +/- 0.301 for Cr, 268.333 +/- 3.153 and 297.361 +/- 3.529 for Mn, 15.194 +/- 0.176 and 16.792 +/- 0.193 for Ni, and 68.778 +/- 0.715 and 74.514 +/- 0.883 for Pb. The highest outdoor particulate matter levels (in mu g/m(3)) in research areas were also determined as 27.103 for fine (PM2.5) and 67.792 for coarse (PM10) aerosols. The findings revealed that Turkish red pine could accumulate noteworthy amounts of heavy metals.Article Citation - WoS: 8Citation - Scopus: 8Simple High-Performance Liquid Chromatographic Method for Determination of Donepezil Hcl in Pharmaceutical Formulations(ACG Publications, 2020) Bulduk, İbrahim; Aydın, Beyza SultanDonepezil HCl is a hydrochloride salt of a piperidine derivative acetylcholinesterase inhibitor and, it uses in treatment demantia of Alzheimer’s disease. In this study, a sensitive and rapid HPLC-UV method was developed and validated for determination of Donepezil HCl in API and tablet dosage forms. Chromatographic separation was performed using a Ace 5 C18 (5 ?m, 250 x 4.6 mm) by using isocratic phosphate buffer at pH:2.0 and acetonitrile (55:45, v/v) mobile phase was used at the rate of 1.2 mL/min. The column temperature was set at 30 ?C and the UV detection was recorded at 268 nm. The method was validated with respect to specificity, precision, accuracy, linearity, repeatability and reproducibility parameters in a concentration range of 25-125 µg/mL. The limit of detection (LOD) and limit of quantification (LOQ) were determined as 1.40 and4.20 µg/mL, respectively. The uncertainty budget of the measurement for Donepezil HCl was estiamted as 5.80 % at 95% confidence level (k = 2).Article Citation - WoS: 3Citation - Scopus: 4Applicability of Low-Intensity Vibrations as a Regulatory Factor on Stem and Progenitor Cell Populations(Bentham Science Publishers, 2020) Baskan, Öznur; Karadaş, Özge; Meşe, Gülistan; Özçivici, EnginPersistent and transient mechanical loads can act as biological signals on all levels of an organism. It is therefore not surprising that most cell types can sense and respond to mechanical loads, similar to their interaction with biochemical and electrical signals. The presence or absence of mechanical forces can be an important determinant of form, function and health of many tissue types. Along with naturally occurring mechanical loads, it is possible to manipulate and apply external physical loads on tissues in biomedical sciences, either for prevention or treatment of catabolism related to many factors, including aging, paralysis, sedentary lifestyles and spaceflight. Mechanical loads consist of many components in their applied signal form such as magnitude, frequency, duration and intervals. Even though high magnitude mechanical loads with low frequencies (e.g. running or weight lifting) induce anabolism in musculoskeletal tissues, their applicability as anabolic agents is limited because of the required compliance and physical health of the target population. On the other hand, it is possible to use low magnitude and high frequency (e.g. in a vibratory form) mechanical loads for anabolism as well. Cells, including stem cells of the musculoskeletal tissue, are sensitive to high frequency, low-intensity mechanical signals. This sensitivity can be utilized not only for the targeted treatment of tissues, but also for stem cell expansion, differentiation and biomaterial interaction in tissue engineering applications. In this review, we reported recent advances in the application of low-intensity vibrations on stem and progenitor cell populations. Modulation of cellular behavior with low-intensity vibrations as an alternative or complementary factor to biochemical and scaffold induced signals may represent an increase of capabilities in studies related to tissue engineering.Article Citation - WoS: 2Citation - Scopus: 2Identification of Cytoplasmic Sialidase Neu2-Associated Proteins by Lc-ms/Ms(Türk Biyokimya Derneği, 2019) Akyıldız Demir, Seçil; Seyrantepe, VolkanBackground: Cytoplasmic sialidase (NEU2) plays an active role in removing sialic acids from oligosaccharides, gly-copeptides, and gangliosides in mammalian cells. NEU2 is involved in various cellular events, including cancer metabolism, neuronal and myoblast differentiation, proliferation, and hypertrophy. However, NEU2-interacting protein(s) within the cell have not been identified yet. Objective: The aim of this study is to investigate NEU2 interacting proteins using two-step affinity purification (TAP) strategy combined with mass spectrometry analysis. Methods: In this study, NEU2 gene was cloned into the pCTAP expression vector and transiently transfected to COS-7 cells by using PEI. The most efficient expression time of NEU2- tag protein was determined by real-time PCR and Western blot analysis. NEU2-interacting protein(s) were investigated by using TAP strategy combined with two different mass spectrometry experiment; LC-MS/MS and MALDI TOF/TOF. Results: Here, mass spectrometry analysis showed four proteins; a-actin, beta-actin, calmodulin and histone H1.2 proteins are associated with NEU2. The interactions between NEU2 and actin filaments were verified by Western blot analysis and immunofluorescence analysis. Conclusions: Our study suggests that association of NEU2 with actin filaments and other protein(s) could be important for understanding the biological role of NEU2 in mammalian cells.