Bioengineering / Biyomühendislik
Permanent URI for this collectionhttps://hdl.handle.net/11147/4529
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Article Expression of Steroidogenic Enzymes in Placentome of Ewes With Pregnancy Toxemia After Two Parturition Induction Methods(Hellenic Veterinary Medical Society, 2023) Risvanlı, A.; Özalp, G. R.; Ortaç, C. T.; Bozkurt, Berkay; Aktar, A.; Yavuz, A.; Korlu, Y.; Şeker, İ.The regulation pattern of important enzymes in placental steroidogenesis and prostaglandin production in ewes with pregnancy toxemia is reviewed. The alterations of gene expressions after the administration of aglepristone (AG) and dexamethasone (DEX) are also discussed. Four healthy (CG) and 22 ewes with experimental pregnancy toxemia were included in the study. Ewes with pregnancy toxemia of group AG (n=9) and group DEX (n=9) were injected twice with 10 mg/kg of aglepristone and once with 5 ml dexamethasone respectively to induce parturition on 141 & PLUSMN;1,3 day of gestation; whereas healthy control [Group CG (n=4)] and pregnancy toxemia [Group PT (n=4)] group received no treatment for parturition induction. Placentomes were immediately collected right after the expulsion of the last lamb. mRNA extraction from total placentome capsule, cotyledon and caruncle was carried out and Real-Time PCR was performed. Serum samples were collected from ewes and cortisol, PGFM, PGE2, estrone sulfate and progesterone concentrations were measured after treatments until parturition. The lowest mRNA expressions of steroidogenic enzymes were detected in group PT. Interestingly expression pattern of steroidogenic enzymes in group AG was similar to group PT. No difference was found in mRNA expressions of 3 & beta;HSD and CYP19 among groups. Between groups, AG-DEX the mRNA expressions in the caruncle of PTGS2/COX2 and PGFS were statistically different respectively (P<0.005). A significant difference could be observed in EP3 expression in the caruncle of DEX and AG compared to CG (P<0.05); however PTGES, EP1, EP2, and EP4 expressions were not statistically different among groups (P>0,05). Estrone sulfate, PGE,2 and PGFM concentrations were statistically different, however, no difference was observed in cortisol levels between groups. The present study suggests that the endocrinologic pathway controlling parturition is different in ewes with pregnancy toxemia. Dexamethasone administration endocrinologically mimicked normal partu-rition, but the genes regulating uterine contractions were similarly expressed, as in group PT. Probably expressions of EP1 and tissue-specific counter-expressions of cervical EP genes could refer to the pathogenesis of insufficient cervical dilatation, observed in pregnancy toxemia and dexamethasone applications.Article Citation - WoS: 3Citation - Scopus: 2Bacterial Mirobiota and Chemical Properties of Turkish Tarhana(Slovak University of Agriculture, 2023) Al, Rabia; Yurt, Mediha Nur Zafer; Ersoy Ömeroğlu, Esra; Can, Özge; Temiz, Sevval Nur; Altunbas, Osman; Soyucok, AliTarhana is one of the traditional Turkish fermented food and it is served as a soup. In this study, bacterial microbiota and chemical properties (acidity, salt, and moisture content) of tarhana samples (n=96) were examined. The metagenomic analysis revealed that Firmicutes were the dominant phylum and Bacillaceae, Enterococcaceae, Paenibacillaceae, Enterobacteriaceae, and Clostridiaceae were the dominant bacterial families. In the samples, Bacillus, Enterococcus, and Paenibacillus were mostly identified at the genus level. Alpha diversity and evenness showed that sample 30 had the highest diversity collected from Izmir. Principal Coordinate Analysis was used to identify relationships of samples at different taxonomic levels and it was found that most of the samples were closely related at the phylum level. Chemical analysis indicated that the acidity of tarhana samples varied between 5.00% and 42.5%, moisture contents were 4.39- 18.66% and salt values were from 0.32% to 6.64%. The results of this study extensively demonstrated the chemical properties and the dominant bacterial communities present in tarhana samples collected from different parts of Turkiye.Article Novel Coronavirus Disease: Overview and Recent Situation(İstanbul Üniversitesi-Cerrahpaşa Sağlık Bilimleri Fakültesi, 2020) Öksel, Ceyda; Bilgi, Eyüp; Başlar, Muhammet Semih; Çeşmeli, Selin; Tomak, Aysel; Hanoğlu, Berçem DilanIn the last days of 2019, local hospitals in Wuhan city (population of 11 million) reported several pneumonia cases with unknown etiology among people linked to the Huanan Seafood Wholesale Market. The virus, which is thought to be the source of the unknown viral infection, was first identified as a new type of coronavirus on January 7, 2020. With the first case reported in Thailand about a week later, the virus’s spread outside the borders of China became apparent. In an alarmingly short time, the new type of coronavirus disease (called COVID-19) started to gain worldwide recognition with the detection of various COVID-19 cases in multiple countries, including Japan, South Korea, USA, Singapore, France, Germany, Italy, Spain, and England. As a result of its rampant spread and fatal clinical manifestations, the coronavirus outbreak was declared a pandemic on March 11, 2020, by the World Health Organization (WHO). Turkey announced its first confirmed case of COVID-19 on the same date that WHO characterized COVID-19 as a pandemic. As of April 2020, the COVID-19 pandemic has traveled to 209 countries and territories around the world, infecting more than 3 million people. Since specific treatment and vaccine for COVID-19 are not yet available, early case detection and preventive healthcare practices (isolation, social distancing, and personal hygiene) play a critical role in combating the COVID-19 outbreak. This review is intended to build an overall picture of the COVID-19 outbreak based on the available scientific knowledge.Article Citation - WoS: 3Citation - Scopus: 4Frequency-Specific Sensitivity of 3t3-L1 Preadipocytes To Low-Intensity Vibratory Stimulus During Adipogenesis(Springer, 2022) Baskan, Öznur; Sarıgil, Öykü; Meşe Özçivici, Gülistan; Özçivici, EnginAdipocyte accumulation in the bone marrow is a severe complication leading to bone defects and reduced regenerative capacity. Application of external mechanical signals to bone marrow cellular niche is a non-invasive and non-pharmaceutical methodology to improve osteogenesis and suppress adipogenesis. However, in the literature, the specific parameters related to the nature of low-intensity vibratory (LIV) signals appear to be arbitrarily selected for amplitude, bouts, and applied frequency. In this study, we performed a LIV frequency sweep ranging from 30 to 120 Hz with increments of 15 Hz applied onto preadipocytes during adipogenesis for 10 d. We addressed the effect of LIV with different frequencies on single-cell density, adipogenic gene expression, lipid morphology, and triglycerides content. Results showed that LIV signals with 75-Hz frequency had the most significant suppressive effect during adipogenesis. Our results support the premise that mechanical-based interventions for suppressing adipogenesis may benefit from optimizing input parameters.Article Citation - WoS: 6Citation - Scopus: 8A “sweet” Way To Increase the Metabolic Activity and Migratory Response of Cells Associated With Wound Healing: Deoxy-Sugar Incorporated Polymer Fibres as a Bioactive Wound Patch(TÜBİTAK, 2022) Dikici, SerkanThe selection of a wound dressing is crucial for successful wound management. Conventional dressings are preferable for the treatment of simple wounds. However, a bioactive wound dressing that supports wound management and accelerates the healing process is required when it comes to treating non-self-healing wounds. 2-deoxy-D-ribose (2dDR) is a small deoxy sugar that naturally occurs in human body. Although we have previously demonstrated that 2dDR can be used to induce neovascularisation and accelerates wound healing in vitro and in vivo, the literature on small sugars is conflicting, and the knowledge on how 2dDR achieves its biological activity is very limited. In this study, several small sugars including D-glucose (DG), 2-deoxy-D-glucose (2dDG), 2deoxy-L-ribose (2dLR) were compared to 2dDR by investigating their effects on the metabolic activities of both human dermal microvascular endothelial cells (HDMECs) and human dermal fibroblasts (HDFs). Then, for the first time, a two-dimensional (2D) scratch wound healing model was used to explore the migratory response of HDFs in response to 2dDR treatment. Finally, 2dDR was incorporated into Poly(3-hydroxybutyrate-co3-hydroxyvalerate) (PHBV) polymer fibres via electrospinning, and the metabolic activity of both types of cells in vitro was investigated in response to sugar release via Alamar Blue assay. The results demonstrated that 2dDR was the only sugar, among others, that enhances the metabolic activity of both HDMECs and HDFs and the migratory response of HDFs in a 2D scratch assay in a dose-dependent manner. In addition to direct administration, 2dDR was also found to increase the metabolic activity of HDMECs and HDFs over 7 days when released from polymer fibres. It is concluded that 2dDR is a potential pro-angiogenic agent that has a positive impact not only on endothelial cells but also fibroblasts, which take a key role in wound healing. It could easily be introduced into polymeric scaffolds to be released quickly to enhance the metabolic activity and the migratory response of cells that are associated with angiogenesis and wound healing.Article Citation - WoS: 12Citation - Scopus: 12Evaluation of Adjuvant Activity of Astragaloside Vii and Its Combination With Different Immunostimulating Agents in Newcastle Disease Vaccine(Academic Press, 2021) Yakuboğulları, Nilgün; Çöven, Furkan Ozan; Cebi, Nusin; Çöven, Fethiye; Çöven, Nejdet; Genç, Rukan; Bedir, ErdalAstragaloside VII (AST-VII), a major cycloartane saponin isolated from Turkish Astragalus species, turned out to be one of the most active metabolites demonstrating Th1/Th2 balanced immune response. As Quillaja saponins are extensively used in adjuvant systems, this study made an attempt to improve AST-VII based adjuvant systems by using different immunostimulatory/delivery agents (monophosphoryllipid A (MPL), Astragalus polysaccharide (APS) and squalene) and to induce cellular and humoral immune response against a viral vaccine. For this purpose, Newcastle Disease vaccine (NDV) was chosen as a model vaccine. Swiss albino mice were immunized subcutaneously with LaSota vaccines in the presence/absence of AST-VII or developed adjuvant systems. AST-VII administration both in live/inactivated LaSota vaccines induced neutralizing and NDV specific IgG, IgG1 and IgG2b antibodies response as well as IL-2 and IL-4 production. APS based delivery systems enhanced the production of neutralizing antibody and the minor augmentation of IFN-? and IL-2 levels. Squalene emulsion (SE) alone or combined with AST-VII were effective in NDV restimulated splenocyte proliferation. As a conclusion, AST-VII and AST-VII containing adjuvant systems demonstrated Th1/Th2 balanced antibody and cellular immune responses in NDV vaccines. Thus, these systems could be developed as vaccine adjuvants in viral vaccines as alternative to saponin-based adjuvants.Article Citation - WoS: 8Citation - Scopus: 12Adjuvant Potency of Astragaloside Vii Embedded Cholesterol Nanoparticles for H3n2 Influenza Vaccine(TÜBİTAK, 2020) Genç, Rukan; Yakuboğulları, Nilgün; Nalbantsoy, Ayşe; Coven, Fethiye; Bedir, ErdalAdjuvants are substances that increase the immune response to a given antigen. In the development of novel vaccine adjuvants/systems, saponins are one of the most attractive molecules due to their altered immunomodulatory activities. In this study, we tried to develop PEG (polyethylene glycol)/cholesterol-based lipid nanoparticles (LNPs) to deliver the Astragaloside VII (AST-VII) and potentiate adjuvant properties of AST-VII for the influenza vaccine. In the formation of PEG/cholesterol/AST-VII-based LNPs (PEG300: Chol-AST-VII LNPs), 3 different primary solvents (acetone, ethanol, and chloroform) were evaluated, employing their effects on hydrodynamic particle size, distribution, surface chemistry, and colloidal stability. Prepared nanoparticles were simply admixtured with inactivated influenza antigen (H3N2) and applied to PMA (phorbol 12-myristate 13-acetate)-ionomycin treated human whole blood to evaluate their cytokine release profile. PEG300: Chol-AST-VII LNPs (80.2 +/- 7.7 nm) were obtained using chloroform as a desolvation agent. Co-treatment of PMA-ionomycin with AST-VII and PEG300: Chol-AST-VII LNPs significantly increased the levels of IL-2 and IFN-gamma, compared to PMA-ionomycin alone. In the presence of H3N2, AST-VII was able to augment IL-17A, while PEG300: Chol-AST-VII LNPs stimulated the production of IFN-gamma. Hemolysis was only observed in PEG300: Chol-AST-VII LNPs (250 mu g/mL) treatment. AST-VII and AST-VII-integrated LNPs could be used as efficacious adjuvants for an inactivated H3N2 vaccine in vitro, and cytokine response through Th1/Th17 route was reported.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.Article Citation - WoS: 8Citation - Scopus: 11Application of Low Intensity Mechanical Vibrations for Bone Tissue Maintenance and Regeneration(TÜBİTAK, 2016) Ölçüm, Melis; Baskan, Öznur; Karadaş, Özge; Özçivici, EnginPhysical exercise is beneficial for bone tissue health, yet its usage is limited for preventing osteoporosis. Even though natural for the bone tissue from development to homeostasis, mechanical loads present with a multitude of physical parameters, including amplitude, duration, frequency, and distribution. Utilizing the most beneficial parameters of mechanical loads may potentiate a nonpharmaceutical tool for biotechnology to prevent and treat bone loss related to aging, bedrest, sedentary lifestyles, weightlessness, and other diseases. Low intensity vibrations (LIVs) consist of mechanical loads with amplitudes smaller than loads prescribed by habitual activity, with a higher frequency. In this review, literature covering LIV signal application on bone tissue and cellular and molecular level is presented. Studies indicate that LIV signals are safe, anabolic, and anticatabolic for skeletal tissue and are of great significance in regenerative medicine applications.Article Citation - WoS: 18Citation - Scopus: 17Cnt Incorporated Polyacrilonitrile/Polypyrrole Nanofibers as Keratinocytes Scaffold(Trans Tech Publications, 2019) İnce Yardımcı, Atike; Aypek, Hande; Öztürk, Özgür; Yılmaz, Selahattin; Özçivici, Engin; Meşe, Gülistan; Selamet, YusufPolypyrrole (PPy) is an attractive scaffold material for tissue engineering with its non-toxic and electrically conductive properties. There has not been enough information about PPy usage in skin tissue engineering. The aim of this study is to investigate biocompatibility of polyacrilonitrile (PAN)/PPy nanofibrous scaffold for human keratinocytes. PAN/PPy bicomponent nanofibers were prepared by electrospinning, in various PPy concentrations and with carbon nanotube (CNT) incorporation. The average diameter of electrospun nanofibers decreased with increasing PPy concentration. Further, agglomerated CNTs caused beads and disordered parts on the surface of nanofibers. Biocompatibility of these PAN/PPy and PAN/PPy/CNT scaffolds were analyzed in vitro. Both scaffolds provided adhesion and proliferation of keratinocytes. Nanofiber diameter did not significantly influence the morphology of cells. However, with increasing number of cells, cells stayed among nanofibers and this affected their shape and size. In this study, we demonstrated that PAN/PPy and PAN/PPy/CNT scaffolds enabled the growth of keratinocytes, showing their biocompatibility.