Bioengineering / Biyomühendislik
Permanent URI for this collectionhttps://hdl.handle.net/11147/4529
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Article The Ordering of Smokers’ Toothpaste Choice Criteria With Fuzzy Model(Atatürk Üniversitesi, 2019) Tarım, Ergün Alperay; Kuruoğlu Kandemir, Emel; Mevsim, VildanAim: There are some measures that smokers can cease or prevent damage caused by smoking. They may also choose some product features that may be more helpful to them like toothpaste selection etc. The preferences of smokers vary because of the variety of toothpaste in the market and a high number of products. The aim of this study is to determine the importance of toothpaste selection criteria in order to determine the decision and toothpaste selection. Material and method: Fuzzy DEMATEL model is used effectively in decision making problems. This model, which can rank the decision criteria in order of importance even for a single individual, is a more effective and important model in ordering the decision criteria of a large number of individuals. In this study, fuzzy DEMATEL model was used to determine the importance of toothpaste selection criteria. In this study, 7 toothpaste selection criteria were determined by data obtained by taking user and expert opinions. After the determination of criteria, the information form was applied to the model to show the criterion importance preferences of smokers. Results: According to the preferences of smokers, the selection criteria of toothpaste were placed in the order with the fuzzy DEMATEL model. The most important criteria is toothpaste package appearance, while the least of the 7 criteria is determined as the criteria that Sensation of Person. Conclusion: As a result, the toothpaste properties that the smokers would prefer, ie the toothpaste selection criteria are listed in importance. In other words, it is given the ranking of preference criteria for smokers when choosing toothpaste.Article Citation - WoS: 4A Src/Abl Kinase Inhibitor, Bosutinib, Downregulates and Inhibits Parp Enzyme and Sensitizes Cells To the DNA Damaging Agents(Türk Biyokimya Derneği, 2018) Kırmızıbayrak, Petek Ballar; İlhan, Recep; Yılmaz, Sinem; Günal, Selin; Tepedelen, Burcu ErbaykentBackground: Poly(ADP-ribosyl)ation (PARylation) catalyzed mainly by PARP1 is a highly regulated posttranslational modification associated with several pathways in cellular physiology and genotoxic deoxyribonucleic acid (DNA) damage response. PAR polymers and PARP enzyme function in DNA integrity maintenance and several PARP inhibitors have entered clinical phase studies for cancer therapies. Material and methods: The effect of bosutinib, a dual Src/Abl kinase inhibitor, on PARylation was fluorometrically measured. The cytotoxic and chemosensitizing effects were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The levels of DNA repair proteins and PARP enzyme were examined by immunoblotting. Results: In this study, bosutinib is characterized as a novel PARP inhibitor. Bosutinib inhibited oxidative stress-induced cellular PARylation and nuclear foci formation by downregulating PARP1 levels. Bosutinib was found to be more cytotoxic on Capan1 cells with BRCA2 mutation. Furthermore by acting as a chemosensitizer, bosutinib enhanced the cytotoxicity of doxorubicin (DOXO) and etoposide (ETP) by decreasing phosphorylation of DNA repair enzymes checkpoint kinase 1 (Chk1) and ataxia-telangiectasia mutated (ATM). Conclusion: By inhibition of both PARP and DNA damage checkpoint kinases, bosutinib increased the phospho-H2AX levels, an early indicator of DNA double strand breaks.Article Optimization of Precursor and Elicitor Utilization in Batch Cultures of Astragalus Trojanus Stev.(2018) Nartop, Pınar; Gürel, Aynur; Akgün, İsmail Hakkı; Bedir, ErdalElicitor and precursor applications are commonly used to induce secondary metabolism in plant cell cultures. In this study, methyl jasmonate, jasmonic acid, salicylic acid and pectin were used as elicitors and ?-sitosterol was used as a precursor in batch cultures of Astragalus trojanus in order to trigger astragaloside IV and cycloastragenol productions. Growth parameters (fresh and dry weights and dry weight percentages) of batch cultures were also evaluated in order to understand the effects of elicitors and precursor on primary metabolism. All elicitors and precursor used in this study triggered metabolite production at different stages of culture period. The highest astragaloside IV accumulation (0.9435 µg/mg) was detected in medium supplemented with 50 µM methyl jasmonate at the 14th day of culture period, whereas the highest cycloastragenol concentration (0.3626 µg/mg) was found in medium supplemented with 50 µM jasmonic acid at the 28th day of culture period. Large scale cultivation was also performed and 0.3759 µg/mg astragaloside IV was detected in medium supplemented with 50 µM methyl jasmonate at the 14th day.Article Optimization of Hnox Protein Production in Escherichia Coli(Sivas Cumhuriyet Üniversitesi, 2017) Sürmeli, Nur BaşakHemoproteinler canlılarda steroid biyosentezinden solunuma, sinyalizasyondan ilaç metabolizmasına kadar pek çok farklı biyolojik süreçlerde önemli görevler üstlenirler. Endüstride, hemoproteinler kolesterol düşürücü pravastatin, rahim ve rahim ağzı kanserlerinin hormonal tedavisinde kullanılan progesteron, alerji ve yangı'ya karşı kullanılan kortizon gibi ilaçların üretiminde kullanılmaktadır. Bunların yanı sıra hemoproteinlerin ilaç geliştirilmesi, biyolojik iyileştirme gibi alanlarda kullanılması da planlanmaktadır. Moleküler biyoloji ve protein tasarımı tekniklerinin gelişmesi ile bu proteinlerin endüstriyel uygulama alanları da genişleyecektir. Hemoproteinlerin bu alanlarda yaygın kullanımı karşısındaki en önemli engellerden biri Hem kofaktörüne bağlı bir şekilde yüksek miktarda hemoprotein üretilememesidir. Bu çalışmada Hem kofaktörüne bağlı bir şekilde üretilen hemoprotein miktarını en yüksek seviyeye getirebilecek koşullar araştırılmıştır. Bu çalışma kapsamında bakteride hemoprotein üretimini etkileyen en önemli üç etken olan indükleyici izopropil ?-D-l-tiyogalaktopiranosid (IPTG), ve Hem öncül molekülü ?-aminolevülinik asit (ALA), ve ekspresyon sıcaklığı incelenmiştir. Bu etkenlerin termofilik hemoprotein TtHNOK üretimine etkisi araştırılmıştır. Özellikle, ALA pahalı bir molekül olduğu için hemoproteinlerin üretiminde kullanılan ALA miktarının optimizasyonu önemlidir. Bu çalışma sonucunda Escherichia coli bakterisinde Hem kofaktörüne bağlı TtHNOK proteinin üretimi için en uygun koşulların düşük sıcaklık, 0,5 mM IPTG ve 1 mM ALA olduğu gösterilmiştir. Bu çalışmada çıkan sonuçlar Hem kofaktörüne bağlı hemoprotein üretiminde ALA konsantrasyonun ve ekspresyon sıcaklığının önemli olduğunu göstermiştirArticle Astragalus Trojanus Stev. Batch Cultures: Cycloartane-Type Metabolite Accumulation in Response To Ph, Sucrose and Casein Hydrolysate(Hacettepe Üniversitesi, 2019) Nartop, Pınar; Gürel, Aynur; Akgün, İsmail Hakkı; Bedir, ErdalI n this study, two grams of callus regenerated from stem and leaf explants of Astragalus trojanus Stev. were cultured in Woody Plant Medium (WPM) supplemented with 1 mg/L 2,4-D for four weeks and used as inoculum in order to investigate the effects of working volume and media composition. The highest biomass was obtained in 250 mL flask with astragaloside IV (1.66 µg/mg) and cycloastragenol (0.19 µg/mg) accumulation. Different concentrations of sucrose and casein hydrolysate (1 and 2 g/L) were also tested and the effect of pH was also investigated. Biomass accumulation cannot be enhanced, however, astragaloside IV and cycloastragenol content was ascended. The highest astragaloside IV (95.23 µg/mg) and cycloastragenol (5.93 mg/mg) accumulations were obtained at pH 6.8 and 2 g/L casein hydrolysate, respectivelyArticle Investigation of Breast Cancer Cells and Phospholipid Cell Membrane Interactions(İzmir Tepecik Eğitim ve Araştırma Hastanesi, 2019) Yıldız, Ahu ArslanObjective: Circulating tumor cells have an important role in the pathogenesis of metastasis. Metastasis occurs through few steps including arrival of circulating tumor cells to distant tissue and organs, their adherence to the target tissue, and then formation of a new tumor. To understand the mechanism of this process it is necessary to investigate the interaction of cancer cells with other molecules and cells of the target tissue, and most importantly interaction with lipids forming the cellular membrane. Methods: To better understand the process of cancer cell adhesion onto lipid membranes and the ionic interactions that are involved in cell adherence, surfaces functionalized with tethered bilayer lipid membrane (tBLM) were utilized in this work as an experimental platform. Either lipid surfaces functionalized with cationic POEPC: PC or anionic POPS: PC fwere examined to observe the ionic interaction of charged phospholipid membrane and MDA-MB231 breast cancer cells. Results: Adhesions of MDA-MB-231 breast cancer cells and NIH-3T3 mouse fibroblast cells to positively charged POEPC: PC lipid surfaces,and their dissemination was observed during examinations using Surface Plasmon Resonance (SPR) method. The results were further confirmed with cell viability and proliferation studies that shows cationic POEPC: PC lipid surfaces were able to facilitate and increase the cell adhesion. Conclusion: These results reveal the cationic phospholipid structures favour the enhanced cancer cell adhesion.Article Citation - Scopus: 21Determination of Superoxide Dismutase Activities in Different Cyanobacteria for Scavenging of Reactive Oxygen Species(Taylor and Francis Ltd., 2015) Güneş, Seda; Tamburacı, Sedef; İmamoğlu, Esra; Dalay, Meltem ConkThere is considerable interest in cyanobacteria as sources of antioxidant pigments, antiinflammatory substances, enzymes such as superoxide dismutase (SOD) and vitamins. Antioxidant enzymes have significant role in the removal of reactive oxygen species produced during visible and ultraviolet irradiance stress in cyanobacteria. One of the most ubiquitous protective enzyme is superoxide dismutase (SOD). Most of cyanobacteria are known to have both FeSOD and MnSOD which are associated with photosystem I and II. These enzymes are responsible for scavenging superoxide radicals.Spirulina platensis and Synechococcus nidulans are widely used cyanobacteria as food supplement and cosmetic due to their bioactive compounds. Although the chemical composition of S.platensis has been investigated by many researchers, research on the relationship between protein content and comparison of SOD activity with other cyanobacteria is limited.Among several SOD producing cyanobacteria, the most promising organisms were investigate in terms of SOD activities in this study. The aim of the present work was to investigate and compare the SOD activities of different cyanobacteria including S. platensis, Pseudanabeana sp., S. nidulans and associate with protein contents. SOD activities of these cyanobacteria were determined by xanthine/xanthineoxidase method.Modified Lowry method was used for protein determination. The analysis results showed that the maximum specific SOD activity obtained was 50.4 U/mg from S.nidulans and the minimum specific SOD activity was 18.4 U/mg from Pseudanabeana sp. Total protein amount of S. nidulans, S. platensis, Pseudanabeana sp. was determined as 0.25 mg/ml, 0.27 mg/ml and 0.43 mg/ml respectively. As a result, Synechococcus nidulans was more efficient at scavenging peroxide radicals than Pseudanabeana sp. © 2015, © 2015 Har Krishan Bhalla & Sons.Conference Object Citation - WoS: 1Kinetic and Thermodynamic Properties of Crude and Three-Phase Partitioned Polygalacturonase From Aspergillus Sojae(Elsevier, 2007) Doğan, Nergiz; Tari, Canan; Göğüş, NihanCommercial preparations of pectinolytic enzymes derived from fungi are well known to have high biotechnological value in the industry. Since potential applications of pectinases in vari- ous fields of food, paper, textile and waste water treatment are increasing, it is important to understand the properties of these enzymes for efficient and effective usage.Conference Object Effect of Symbiotic Relationship of Lactobacillus Butgaricus 77 and Streptococcus Thermophilus 9512 on Betagalactosidase and Lactic Acid Production(Elsevier, 2007) Üstok, Fatma Işık; Tari, Canan; Harsa, ŞebnemEnzyme production which is a growing field of biotechnology has an annual world sale close to billion dollars. Therefore isolation of new strains producing novel enzymes is important for industrial enzyme production.Conference Object Citation - WoS: 1Optimization of Exo-Polygalacturonase Production From Orange Peel by Aspergillus Sojae(Elsevier, 2010) Büyükkileci, Ali Oğuz; Tarı, Canan; Fernandez-Lahore, H. M.; Gençkal Demir, Hande; Göğüş, NihanPectinases catalyze the degradation of pectic substances, thus they are used extensively in fruit juice and wine industry to facil-itate extraction and clarification. Aspergillus species, in particular Aspergillus niger, have long been utilized for production of pectinases. Previous studies of our group showed that A. sojae has a potential to produce enhanced amount of polygalacturonase, which is one of the pectic enzymes, in both submerged and solid-state cultures (Gogus et al., 2006; Tari et al., 2007). In this study, several agricultural products were screened in an effort to find a cheap and abundant substrate for submerged polygalacturonase production using a UV-mutated A. sojae strain. Medium composition was optimized to further enhance the enzyme level. Experiments were designed and analyzed statistically using the trial version of the statistical software, Design Expert.