Chemical Engineering / Kimya Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/14
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Article Citation - WoS: 5Citation - Scopus: 5Evaluation of Liposomal and Microbubbles Mediated Delivery of Doxorubicin in Two-Dimensional (2d) and Three-Dimensional (3d) Models for Breast Cancer(Galenos Publishing House, 2021) Aydın,M.; Özdemir,E.; Altun,Z.; Kılıç,S.; Aktaş,S.Objective: Liposomal cancer treatment strategies are useful in removing the side effects that were the main concern in recent years. In this study, we prepared microbubble (MBs) conjugated with DOX-loaded liposomes (DOX-loaded MBs) and investigated their effectiveness in in vitro breast cancer cells in two dimensions (2D) and three dimensions (3D). Materials and Methods: With this aim, breast cancer cells with different features (4T1, MDA-MB231, MCF-7) were growth in 2D and 3D dimensions. The cytotoxic and cell death effects under different conditions, durations and doses were evaluated with WST-1, trypan-blue, colony counts. Apoptotic effects were investigated with flow cytometric Annexin-V-PI and immunohistochemical (Ki-67, caspase 3, 8, 9) methods. Results: After free DOX and LipoDOX were applied, the proliferation index of three cell lines reduced. Intrinsic and extrinsic apoptotic pathways were activated in both 2D and 3D models. However, this effect was observed at lower levels in the 3D model due to the difficulty of diffusion of DOX into the spheroids. Additionally, the suitability of the 3D model for breast cancer cells was supported by formation of ductus-like structures and spheroids. Cell deaths were not observed significantly with the DOX-loaded microbubbles due to rising of MBs to the surface and not reaching spheroids held in matrigel of 3D model. Conclusion: DOX and LipoDOX showed anti-proliferative and apoptosis-inducing effects in breast cancer cells. However, these effects indicated variability depending on the cell lines and 2D or 3D model types. ©Copyright 2021 by the the Turkish Federation of Breast Diseases Societies.Article Citation - WoS: 11Citation - Scopus: 13Effect of Cnt Incorporation on Pan/Ppy Nanofibers Synthesized by Electrospinning Method(TÜBİTAK, 2020) İnce Yardımcı, Atike; Tanoğlu, Metin; Yılmaz, Selahattin; Selamet, YusufIn this study, carbon nanotubes (CNTs) added polyacrylonitrile/polypyrrole (PAN/PPy) electrospun nanofibers were produced. Average diameters of the nanofibers were measured as 268 and 153 nm for 10 and 25 wt% of PPy contents, respectively. A relatively higher strain to failure values (23.3%) were observed for the low PPy content. When as-grown CNTs (1 and 4 wt%) were added into the PAN/PPy blends, disordered nanofibers were observed to form within the microstructure. To improve the interfacial properties of CNTs/PAN/PPy composites, CNTs were functionalized with H2SO4/HNO3/HCl solution. The functionalized CNTs were well dispersed within the nanofibers and aligned along the direction of nanofibers. Therefore, beads formation on nanofibers decreased. The impedance of the nanofibers was found to decrease with the PPy content and CNT addition. These nanofibers had a great potential to be used as an electrochemical actuator or a tissue engineering scaffold.Article Citation - WoS: 47Citation - Scopus: 54Olive Leaf Extracts Protect Cardiomyocytes Against 4-Hydroxynonenal Toxicity in Vitro: Comparison With Oleuropein, Hydroxytyrosol, and Quercetin(Georg Thieme Verlag, 2014) Bali, Elif Burcu; Ergin, Volkan; Rackova, Lucia; Bayraktar, Oğuz; Küçükboyacı, Nurgün; Karasu, ÇimenOlive (Olea europaea) leaf, an important traditional herbal medicine, displays cardioprotection that may be related to the cellular redox modulating effects of its polyphenolic constituents. This study was undertaken to investigate the protective effect of the ethanolic and methanolic extracts of olive leaves compared to the effects of oleuropein, hydroxytyrosol, and quercetin as a positive standard in a carbonyl compound (4-hydroxynonenal)- induced model of oxidative damage to rat cardiomyocytes (H9c2). Cell viability was detected by the MTT assay; reactive oxygen species production was assessed by the 2′,7′-dichlorodihydrofluorescein diacetate method, and the mitochondrial membrane potential was determined using a JC-1 dye kit. Phospho-Hsp27 (Ser82), phospho-MAPKAPK-2 (Thr334), phospho-c-Jun (Ser73), cleaved-caspase-3 (cl-CASP3) (Asp175), and phospho-SAPK/JNK (Thr183/Tyr185) were measured by Western blotting. The ethanolic and methanolic extracts of olive leaves inhibited 4-hydroxynonenal-induced apoptosis, characterized by increased reactive oxygen species production, impaired viability (LD50: 25 μM), mitochondrial dysfunction, and activation of pro-apoptotic cl-CASP3. The ethanolic and methanolic extracts of olive leaves also inhibited 4-hydroxynonenal-induced phosphorylation of stress-activated transcription factors, and the effects of extracts on p-SAPK/JNK, p-Hsp27, and p-MAPKAPK-2 were found to be concentration-dependent and comparable with oleuropein, hydroxytyrosol, and quercetin. While the methanolic extract downregulated 4-hydroxynonenal-induced p-MAPKAPK-2 and p-c-Jun more than the ethanolic extract, it exerted a less inhibitory effect than the ethanolic extract on 4-hydroxynonenal-induced p-SAPK/JNK and p-Hsp27. cl-CASP3 and p-Hsp27 were attenuated, especially by quercetin. Experiments showed a predominant reactive oxygen species inhibitory and mitochondrial protecting ability at a concentration of 1-10 μg/mL of each extract, oleuropein, hydroxytyrosol, and quercetin. The ethanolic extract of olive leaves, which contains larger amounts of oleuropein, hydroxytyrosol, verbascoside, luteolin, and quercetin (by HPLC) than the methanolic one, has more protecting ability on cardiomyocyte viability than the methanolic extract or each phenolic compound against 4-hydroxynonenal-induced carbonyl stress and toxicity.Article Citation - WoS: 48Citation - Scopus: 58Micro-Encapsulation of Ozonated Red Pepper Seed Oil With Antimicrobial Activity and Application To Nonwoven Fabric(John Wiley and Sons Inc., 2013) Özyıldız, Figen; Karagönlü, S.; Başal, Güldemet; Uzel, Ataç; Bayraktar, OğuzIn recent years, functional fabrics possessing antimicrobial activity have drawn significant interest because antibiotic resistance is becoming widespread among pathogenic micro-organisms. The aim of this study was to produce microcapsules incorporating ozonated red pepper seed oil (ORPSO) with antimicrobial properties and apply them to nonwoven fabrics to prepare functional textiles. Red pepper seed oil (RPSO) was ozonated and micro-encapsulated via a complex coacervation method using gelatin (GE) and gum arabic (GA) as wall materials. While micro-encapsulation yield and oil loading decreased with increases in the amount of surfactant, the mean particle size increased. The antimicrobial activity of the oil was tested via the disc diffusion method. The microcapsules were also tested using the agar well method. While RPSO had no effect on the test micro-organisms, the ORPSO and microcapsules containing ORPSO were found to be active against the test micro-organisms. The microcapsules were then applied to nonwoven fabric using the padding method to produce a disposable functional textile. The microcapsule-impregnated functional fabrics provided a 5 log decrease in 1 h. It is therefore possible to functionalize nonwoven fabrics to have antimicrobial activity against antibiotic-resistant micro-organisms, using microcapsules containing ORPSO.