Browsing by Author "Özbilgin K."
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Item Insulin: Does it induce follicular arrest in the rat ovary?(Parthenon Publishing Group Ltd, 2002) Kuşcu N.K.; Koyuncu F.; Özbilgin K.; Inan S.; Tuǧlu I.; Karaer Ö.The goal of this study was to investigate histological changes of the rat ovary treated with either insulin or insulin plus human chorionic gonadotropin (hCG). The study was conducted in Celal Bayar University, School of Medicine, Animal Research Laboratory. Eighteen adult female Wistar rats were divided into three groups to receive saline, or insulin, or insulin plus hCG for 4 weeks. At the end of treatment the rats were sacrificed and the ovaries were evaluated with hematoxylin and eosin. There was no abnormal change in rats treated with saline. A thickened capsule, stromal hypertrophy and stromal cell hyperplasia, and no developing follicles, were observed in the insulin-only group. A thin capsule, developing follicles and corpora lutea, and normal theca cells and stroma were observed in the insulin-plus-hCG group. We conclude that insulin may lead to histological changes similar to stromal hyperthecosis and polycystic ovary syndrome, and may be one of the factors causing follicular arrest.Item The maturity of intestinal neomucosa: Integrin expression and ultrastructural aspects(2004) Günşar C.; Vatansever H.S.; Arslan O.A.; Şencan A.; Müftüoǧlu S.; Özbilgin K.; Kaymaz F.; Mir E.Background/purpose The maturity of neomucosa growing on a serosal surface for the treatment of short bowel syndrome still is questionable. The aim of this study was to evaluate the intestinal neomucosa to assess its histologic maturity. Methods A 6-cm-long isolated ileal segment (IS) was prepared in 8 Wistar albino-type rats. The IS was divided from the antimesenteric side, and 2 intestinal tubes were established, which shared a common wall and a common pedicle. After ileal biopsy sampling for the control group (CG), the IS was fashioned into a mucous fistula. Eight weeks later, all the rats were killed, and the ISs were investigated for neomucosal growth. Sections were prepared with periodic acid shift (PAS) and H & E staining for light microscopy. They also were evaluated by transmission electron microscopy. The microscopic morphology of the 2 groups was evaluated. Immunohistochemical staining was performed to show the expression of the tissue β1, α3 and α2β1 integrin subunits of both the neomucosa (NS) and control group (CG) segments. Results Sections of the NS showed a well-arranged columnar epithelial cell layer with goblet cells that were generally located superficially and with a complete basement membrane. Under the electron microscope, the sections from the NS group showed an epithelial cell layer with proper microvilli of the same height, although they were shorter than those of the CG, and tight intercellular junctions between the epithelial cells. Significant differences between the NS and CG groups were found in the measurements of villus width at base, microvillus surface, and microvillus height. The lamina propria consisted of rich collagen fibers and active fibroblasts in the NS group. In the immunohistochemical staining, although β1 integrine showed a dense distribution (+++) in the lamina propria, particularly localizing at the depth of the tunica mucosa layer, α3 integrin was observed to have a less dense immunoreactivity (++) in both groups. The expression of α2β1 integrin showed slight and dispersed (+) staining. Conclusions The NS showed histologic maturity and ultimate structural similarity with the native small bowel mucosa, which provides strong indirect evidence for the proper functioning of the neomucosa. © 2004 Elsevier Inc. All rights reserved.Item Ischemic preconditioning - Association of reperfusion and brain damage with metabolic state; [İskemik ön tanitim-reperfüzyon ve beyin hasarinin metabolik durumu ile ilişkisi](2005) Tuǧlu I.; Vural K.; Cezayirli E.; Varol T.; Özbilgin K.Stroke and cardiac arrest, which are major causes of death and disability, affect millions of individuals around the world and are responsible for the leading health care costs of all diseases. The ischemia-induced neuronal death is an energy dependent process and is the result of activation of cascades of detrimental biochemical and histological events that include perturbion of calcium homeostasis leading to increased excitotoxicity, malfunction of endoplasmic reticulum and mitochondria, elevation of oxidative stress causing DNA damage, alteration in proapoptotic gene expression, and activation of the effector caspases and endonucleases leading to the final degradation of the genome. Ischemic preconditioning of the brain describes the neuroprotection induced by a short, conditioning ischemic episode to a subsequent severe ischemic episode. The tolerance of the brain to an ischemic injury depends not only on the duration and severity of insufficient blood flow but also on various pre- and post-ischemic factors that are able to influence the post ischemic outcome. Recent experimental studies focus on the preischemic factors, that can increase the ischemic tolerance, among which the suppression of metabolic rate, the increase of brain tissue energy reserves and the inhibition of membrane permeability of cations are of particular importance. During the induction phase, aspartate and adenosine receptors, and oxygen free radicals and conservation of energy metabolism are required. Protein kinases, transcription factors, and immediate early genes appear to transduce the signal into a tolerant response. The brain succumbs to ischemic injury as a result of loss of metabolic stores, excessive intracellular calcium accumulation, oxidative stress, and potentiation of the inflammatory response. Neurons can also die via necrotic or apoptotic mechanisms, depending on the nature and severity of the insult. While it has been widely held that ischemia is notable for cessation of protein synthesis, brain regions with marginal reduction in blood supply are especially capable of expressing a variety of genes, the functions of many of which are only beginning to be understood. Gene expression is also upregulated upon reperfusion and reoxygenation. Brain extracellular levels of glutamate, aspartate, GABA and glycine increase rapidly following the onset of ischemia, remain at an elevated level during the ischemia, and then decline following reperfusion. In the early stages neuronal responses to ischem ia are dependent on the modulation of ion channels. Reactive oxygen species generated during ische-mia-reperfusion contribute to the injury. Oxygen free-radicals serve as important signalling molecules that trigger inflammation and apoptosis. The use of appropriate animal models is essential to predict the value and effect of therapeutic approaches in human subjects. Animal models should be used to determine dosage and duration of therapy, which will vary with the pharmacokinetic properties of different agents. Finally, physiological monitoring for the metabolic condition such as cerebral blood flow, blood pressure and gazes, body temperature, glycemia, etc., should be performed to eliminate confounding variables and to observe adverse systemic effects. Therefore, it is very important to know the experimental process, survey of animals, neurologic scoring, histological methods which highly affect the explanation of the results. In this review, we discuss mechanisms of ischemic brain damage and reperfusion related to metabolic condition and histology.Item The aromatase inhibitor anastrozole is associated with favorable embryo development and implantation markers in mice ovarian stimulation cycles(2005) Karaer Ö.; Vatansever H.S.; Oruç S.; Özbilgin K.; Cilaker S.; Koyuncu M.F.Objective: To investigate the embryonic and endometrial effects of anastrozole in preimplantation and implantation phases in FSH-induced cycles in mice. Design: Blind randomized study. Setting: University research laboratory. Animal(s): Twenty-seven mature female mice. Intervention(s): Single-dose anastrozole (25 mg/kg [0.75 mg]), recombinant FSH (5 IU/mL), and hCG (5 IU/mL) (n = 9); recombinant FSH (5 IU/mL) and hCG (5 IU/mL) (n = 9); or sterile saline (1 mL) (n = 9). The morning of finding the vaginal plug was designated as day 1 of embryonic development (E1). Three mice from each group were sacrificed on E1 and embryos aspirated from uterine tubes. The rest of the mice were sacrificed on E2.5-3 and uteruses removed. Main Outcome Measure(s): Embryo quality, endometrial histologic evaluation, and immunohistochemical analysis of tumor necrosis factor-α, leukemia inhibitory factor, laminin, and collagen IV staining. Result(s): Anastrozole use in FSH-induced cycles not only caused an increase in preimplantation receptivity and implantation but also supported release of implantation markers. The enhanced embryo development seen in this study would explain the higher implantation because embryo development is synchronized with endometrial development. Conclusion(s): In mice, the use of anastrozole in FSH-induced cycles has a positive effect on embryo quality and implantation. This effect might be species dependent, and human studies are needed. ©2005 by American Society for Reproductive Medicine.Item Computer assisted image analysis of peroxidase stained endometrial tissue(2006) Toprak A.B.; Vatansever S.; Özbilgin K.Aim: In immunohistochemistry, antibodies are used to detect and localize antigens in cellular compartments in sections taken from frozen or paraffin blocks. Currently, computerized image processing techniques are widely available to analyze immunohistochemically stained tissues; however, the image analysis programs are generally highly specific and expensive. We aimed to show the feasibility of computer assisted image analysis (CAIA) by using two computer programs currently in widespread use. Methods: Two available computer programs, Adobe Photoshop CS and ImageJ, were used to separate areas in the same tissue sections stained with NOS antibody and labeled with peroxidase in human endometrial tissue. CAIA was made on the relevant images using these two programs. Results: There was a significant difference among the groups according to staining intensity, in all three grades of staining (P < 0.001, P < 0.05, and P < 0.001, respectively). Subjective assessment of the images was in good agreement with objective CAIA. One (+) positive stained area was greater in group 1 and less in group 2 and group 3 (P < 0.001 and P < 0.001, respectively). Group 3, which was considered as the most intensely stained by the observer, had the greatest amount of ++ staining. Conclusion: CAIA is a safe and reliable method of analyzing tissue samples stained using immunohistochemical methods. © TÜBİTAK.Item The effect of cardiopulmonary bypass on the expression of inducible nitric oxide synthase, endothelial nitric oxide synthase, and vascular endothelial growth factor in the internal mammary artery(2006) Toprak V.; Şirin B.H.; Tok D.; Özbilgin K.; Saribülbül O.Objective: Endothelial function of a vessel may be impaired by local or systemic inflammation initiated by cardiopulmonary bypass (CPB) during coronary artery bypass graft (CABG) surgery. The present study was designed to investigate the early effects of CPB on nitric oxide production and vascular endothelial growth factor (VEGF) expression in internal mammary artery (IMA). Design: Prospective study. Setting: University hospital. Participants: Twenty patients who were scheduled for elective CABG with CPB. Interventions: IMA sections were studied immunohistochemically from these patients. The samples were taken from the distal end of the IMA before the institution of CPB and just before the construction of the IMA-left anterior descending artery anastomosis. Measurement and Main Results: After CPB, VEGF and endothelial nitric oxide synthase immunoreactivity increased significantly when compared with baseline values in the endothelium (p = 0.0156, p = 0.0313) and adventitia (p = 0.0313, p = 0.0001), respectively. No significant change was observed in inducible nitric oxide synthase immunoreactivity. Conclusions: The increase in eNOS expression may have been induced by the inflammation caused by CPB. © 2006 Elsevier Inc. All rights reserved.Item Analysis of the effects of inhibitor and activator systems (smad's proteins) of TGF-βs on chick neural tube closure; [Tavuk Nöral Tüp Kapanmasinda TGF-βs Inhibitör ve Aktivatör Sisteminin (Smad's Proteinleri) Etkilerinin Araştirilmasi](2010) Umur N.; Vatansever S.; Umur A.Ş.; Özbilgin K.; Selçuki M.The families of TGF-βs and Smads proteins that controls its intracellular signaling pathways are known to play a role in early neurulation. The aim of this study is to demonstrate distribution of TGF-βs (1, 2, 3) and Smads (1/2/3, 6, 7) proteins as a system in different hours of neural tube development of chick embryos. The SPF eggs were incubated at 37.8±2°C for 24th, 30th, 48th, 72nd h. After that, embryos were examined using immunohistochemistry and western blotting techniques. To the results, TGF-βs immunoreactivities (particularly TGF-β3) at the 24th, 30th and 48th h of chick development (during neural tube closure) were determined and decreased at the 72nd h (after neural tube closure), but expressions of TGF-βs were detected in all stage of embryos in western blotting. While Smad 1/2/3 immunoreactivitiy and expression was less than that of the Smad 6 and 7 at the 24th, it was increased at the 30th h. Smads proteins immunoreactivities were decresead at the 72nd h. In conclusion, the members of TGF-βs are play a role in chick neural tube closure, the secretions of TGF-βs are controlled different Smad proteins. In addition, immunoblotting results showed that TGF-βs and Smads proteins were effective in the development of all tissues and organs of the embryos.Item The role of selectins in the first trimester pregnancy loss(Studio K Krzysztof Molenda, 2014) Eskicioglu F.; Laçin S.; Özbilgin K.; Köse C.Objective: There are no well-defined findings about reasons for first trimester abortion in some pregnancy cases. Selectins are cell adhesion proteins which are important for blastocyst implantation in the decidua. The goal of the study was to investigate the role of selectins in first trimester pregnancy loss by immunohistochemistry. Study design: Decidual and placental tissue samples have been obtained from the women with unwanted pregnancy as the control group (n=40) and missed abortion (n=40) as the study group. Immunohistochemistry technique has been used to compare P, L and E-selectin expression of the fibroblast and the decidual cells in uterine decidual stroma; and fibroblasts and mesenchymal cells in placental villous stroma. Immunostaining for P,L,E-Selectin has been evaluated semiquantitatively by HSCORE analysis. Results: Decidual cells, for E and L-selectin showed stronger staining in the study group than controls, and the difference was statistically significant (p = 0.001, p = 0.001). P-selectin showed stronger staining in the control group, but the difference was not as significant as the E and L-selectins (p=0.04). In the placenta, cytotrophoblasts and syncytiotrophoblasts showed stronger staining for P,E,L-selectins for the control group (p<0.001, p=0.001 and p<0.001, respectively). Conclusion: Strong expression of each of the three investigated selectins in healthy pregnancy villi shows their contribution to implantation and strong placentation. There is a need for better understanding of the functions of adhesive molecules in these events to reveal unknown causes for pregnancy loss.Item The diferentiation of neuronal cells from mouse embryonic stem cells; [Fare embriyonik kök hücrelerden nöronal hücrelerin farkli{dotless}laşmasi{dotless}](Veteriner Fakultesi Dergisi, 2014) Umur N.; Vatansever H.S.; Umur A.Ş.; Türköz E.; Özbilgin K.With new technologies emerging today, the importance of stem cells in the cell therapy of nervous system diseases is supported by recent studies. Therefore, the development of neuronal cell differentiation protocols from stem cells is of great importance. In our study, the differentiation of neuronal and neuroglial cells from mouse embryonic stem (ES) cell line and their analysis with neuronal cell markers are aimed. Mouse ES cells were differentiated to neurogenic series cells by adding N2 and bFGF to the culture medium on coated Fibronectin dishes. For the identification of differentiated cells, they were evaluated by light microscopy using immunhistochemistry techniques and by electron microscopy. Indirect immunohistochemical staining method was performed with SSEA-1 (mouse embriyonic stem cells marker), Nestin (neural precursor cells marker), βIII-Tubulin (neuronal cells marker), MAP-2 (neuronal cells marker), GFAP (astrocyte marker), and O4 (oligodendrocyte marker). After 1 week of differentiation of cells, immunoreactivities of SSEA-1 and Nestin were detected to be negative and moderate, respectively. After 2 weeks culture time, the differentiation was still continuing and especially positive immunoreactivities of β-III Tubulin and MAP-2 and weak immunoreactivities of O4 and GFAP were supported neuronal differentiation. In conclusion, our results suggest that neuronal cell derived from mouse ES cells were differentiated particularly to neuron using N2+bFGF+fibronectin culture condition. Therefore, these differentiated cells may be used as a treatment method in degenerative diseases of the nervous system.Item A comparison of the molecular distribution of proangiogenic factors in endometrium of missed abortions and of voluntary first trimester termination cases(S.O.G. CANADA Inc., 2015) Özçakir T.; Turan M.A.; Şimşek F.; Atay C.; Vatansever S.; Özbilgin K.Objective: The authors aimed to evaluate the angiogenic changes that occur in the cases with missed abortions compared with the voluntary termination of pregnancy as control group, with this controlled clinical study. Materials and Methods: The study included fifteen healthy volunteer women with unwanted pregnancy less than 10th gestational week in an academic research environment. The patients were 19 women between 6th and 11th gestational weeks diagnosed with missed abortion as the patient group. Immunohistochemistry was utilized to examine temporal and spatial expression of vascular endothelial growth factor (VEGF) and their two receptors: VEGF-R1 (Flt-1) and VEGF-R2 (Flk-l/KDR), and Trombospondin-1, eNOS, iNOS, and HIF-la in the both deciduas and placenta of the both groups. Results: This study discovered the significant difference (p < 0.005) between the groups of controlled and missed abortion in the decidual and placental cell components, and has put forward that thrombospondin and iNOS have an impact on abortion through antiangiogenic effect in cases of missed abortions. Conclusions: The potential role of molecules affecting angiogenesis in the etiology of missed abortion has been evaluated and the authors aimed for this to be a guide for studies on further treatments and on the prevention of the development of missed abortions.Item The role of angiogenic factors in first trimester pregnancy losses(S.O.G. CANADA Inc., 2017) Eskicioǧlu F.; Özbilgin K.; Taşkend S.; Önal T.; Gökmen T.Objective: A good blood supply towards the peri-implantation endometrium is an essential requirement for pregnancy. Intermedin (IMD), vascular endothelial growth factor (VEGF), and endothelial nitric oxide synthase (eNOS), are angiogenic and vasoactive agents that play contributory roles in endometrial vascularity. The goal of this study was to immunohistochemically investigate the roles of various vasoactive factors in first trimester pregnancy losses. Materials and Methods: This was a prospective case-controlled study carried out on decidual and placental tissue samples obtained from women with unwanted pregnancies who served as the control group (n=10), and those with missed abortions who were the "missed abortion group"(n = 10). Immunohistochemistry techniques were used to compare IMD, receptor activity modifying protein (RAMP)1, RAMP2, RAMP3, VEGF, and eNOS expression of decidual and placental cells. Immunostaining for these factors was evaluated semiquantitatively by H-score analysis. Results: IMD and RAMPs in decidual cells exhibited higher expression in the control group. However, IMD and RAMP2 had a stronger expression in placental cells in the missed abortion group. In the control group, VEGF and eNOS had a higher expression in decidual cells and on the placental side, especially in syncytiotrophoblasts and cytotrophoblasts. Conclusion: Expressions of vasoactive agents, such as IMD, VEGF, and eNOS, decrease in first trimester pregnancy losses. Additionally, a compensatory mechanism against decreased endometrial and subendometrial vascularity results in the death of the embryo/fetus enhances in missed abortion cases. This mechanism characterized by increased expressions of IMD and RAMP2 initially begins in the syncytiotrophoblasts and cytotrophoblasts.Item Effects of α-lactalbumin and sulindac on primary and metastatic human colon cancer cell lines(De Gruyter, 2019) Aydemir I.; Vatansever S.; Özbilgin K.Background: HAMLET (human α-lactalbumin made lethal to tumor cells) and sulindac are active ingredients which are used in the treatment of cancers. Under both in vivo and in vitro conditions, HAMLET binds to the surface of tumor cells and enters the cells. Sulindac is one of nonsteroidal anti-inflammatory drugs. It inhibits the growth of tumor cells by inducing the apoptosis. In our study, we aimed to investigate effects of α-lactalbumin and sulindac on COLO- 320 primary and COLO-741 metastatic human colon carcinoma cell lines via mitochondrial apoptotic pathway by indirect immunocytochemistry and TUNEL assays. Materials and methods: The effects of α-lactalbumin and sulindac were assessed by using MTT assay at 24, 48 and 72 h and apoptosis markers caspase-3, caspase-9 and cytochrome-c were detected using immunocytochemistry and TUNEL methods. Results: It was appeared that α-lactalbumin and sulindac may triggger mechanisms of apoptosis in both primary and metastatic colon carcinoma cell lines and the primary colon carcinoma cell line was affected more than the metastatic cells. Conclusion: It is proposed that α-lactalbumin and sulindac can be used in cancer treatments and future in vivo experiments. © 2019 De Gruyter. All rights reserved.Item Effects of verteporfin-mediated photodynamic therapy in breast cancer cells(National Institute of Science Communication and Information Resources, 2020) Sönmez P.K.; Turhan A.; Öztatlıcı M.; Özbilgin K.Photodynamic therapy works with a photosensitizer that is stimulated when exposed to a light source of a specific wavelength and produces a form of oxygen that can be used in cancer treatments. In this study, we investigated the effect of laser on apoptosis on breast cancer cell lines (MDA-MB-231) treated with verteporfin in cell culture media. Verteporfin added MDA-MB-231 cells were incubated without light for 24 hours after applying laser light at a wavelength of 695 nm at an intensity of 50 J/cm2 at various times. Anti-proliferative effects were evaluated by immunoreactivity of anti-Bcl-2 and anti-Bax antibodies by immunocytochemical staining. When anti-Bax/Anti-Bcl-2 ratio are compared, the ratio of 1.5 in the control group cells decreases in short-term laser applications, while it approaches normal values in the 7th min after long-term laser application and reaches a very high value in the 9th min. Therefore, our results suggest that verteporfin-mediated PDT may be a potential combined therapy strategy against breast carcinoma by increasing apoptosis. © 2020, National Institute of Science Communication and Information Resources (NISCAIR). All rights reserved.Item Intraoperative evaluation of testicular vascularization and perfusion in rat testicles with indocyanine green (ICG)/near-infrared (NIR) fluorescent imaging after torsion–detorsion and reperfusion(Springer Science and Business Media Deutschland GmbH, 2022) Şencan A.; Tanrıverdi H.İ.; Şimşek F.B.; Usta İ.B.; Üçöz M.; Özbilgin K.Introduction: The aim of this study was to evaluate testicular perfusion and vascularization with intraoperative ICG/NIR imaging in a testicular ischemia–reperfusion model and to investigate the effects of ICG on testicular tissue. Materials and methods: 24 male rats were divided into four groups. In the ICG group, only ICG was given and images of the testicles were recorded with NIR camera. In the torsion group, the testicles were left in torsion for 4 h. ICG/NIR images were obtained after torsion and detorsion. In the reperfusion group, ICG/NIR images of the testicles were obtained at the 4th hour of reperfusion. After the procedures, testicles were collected and evaluated with histological, immunohistochemical examination and qRT-PCR. Results: There was no histologically negative effect of ICG on testicular tissue. There was no testicular perfusion in the torsion group, but perfusion started after detorsion. At the 4th hour of reperfusion, testicular perfusion continued. TNF-a, IL-6, MCP-1 and caspase-3 immunoreactivity were found to be at low levels in the control and ICG groups, while high in the torsion and reperfusion groups (p < 0.05). In qRT-PCR, TNF-a, IL-6, MCP-1 and caspase-3 expressions were lower in the control and ICG groups, but higher in the torsion and reperfusion groups. Conclusion: There was no histologically negative effect of ICG on testicles. The ICG/NIR imaging technique seems to be a feasible method in testicular torsion and may contribute to the surgeon in the intraoperative management of testicular torsion. In testicles that started to be perfused after detorsion, perfusion still continued at the 4th hour of reperfusion. Our next goal is to test whether testicles showing ICG fluorescence in during reperfusion maintain their viability for long term. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.