Browsing by Author "Ozbilgin, MK"

Now showing 1 - 15 of 15
  • No Thumbnail Available
    Item
    Changed Bcl:Bax ratio in endometrium of patients with unexplained infertility
    Vatansever, HS; Lacin, S; Ozbilgin, MK
    Apoptosis has been shown to be an important regulator of endometrial function during the menstrual cycle and implantation. Recently, some possible implantation defects were identified in patients with unexplained infertility. In this study, we investigated the role of spontaneous apoptosis, which is regulated by death regulatory genes, such as Bc1-2, Bax, p53, and isoenzymes of nitric oxide synthases; eNOS and iNOS during the implantation window in women with unexplained infertility. Endometrial samples were evaluated from fertile (n = 15) and unexplained-infertile women (n = 15) during post-ovulatory 7th or 8th day of their menstrual, cycles. Apoptotic cells were detected using the dUTP nick-end labelling assay and Bcl-2, Bax, p53, iNOS and eNOS were assessed immunohistochemically. Reduced apoptotic cells, weak immunoreactivity of p53 and strong immunoreactivity of Bcl-2 were observed in the unexplained-infertile group compared with the fertile group (p < 0.001). Bax intensity was similar in both groups. White weak iNOS immunoreactivity was detected in both groups, moderately increased eNOS immunoreactivity was observed in infertile cases. Spontaneous apoptosis is reduced in the endometrium of unexplained-infertile women, and is associated with the changed Bcl-2:Bax ratio. This finding may be a contributing factor to defective implantation causing infertility in this group of patients. (c) 2005 Elsevier GmbH. All rights reserved.
  • No Thumbnail Available
    Item
    Effects of adrenomeduline and ramp2 on the lung of mice exposed to total body radiation
    Ozbilgin, MK; Karaman, GZ; Gencur, S; Gumustepe, E; Kurtman, C
    Background: Adrenomedullin (AM) and its receptor, receptor activity-modifying protein (RAMP) 2 have pleiotropic regulatory functions in normal tissue and cancer tissue. AM is produced and secreted both numerous stromal cells and tumor cells. This study aims to investigate a possible role of AM and RAMP2 in the radiation exposure in the normal lung tissue. Materials and Methods: Four groups with 6 male adult Swiss Albino mice per group were investigated. The mice were subjected to a 500 cGy single-dose radiation exposure in the total body radiation device and lung tissues were collected. 1, 2, and 7 days after radiation exposure, with 1 reference group which was not exposed to radiation. Results: The general histology and the immunohistochemistry of the tissue samples prepared with anti-AM, anti-RAMP2, and monoclonal antibodies were investigated, yielding a statistically significant increase for AM on day 3 and for RAMP2 on day 1 after radiation exposure. Conclusion: The observed increase of AM and RAMP2 concentrations in the normal tissue matrix after radiation exposure may play a role in the side effects of radiotherapy.
  • No Thumbnail Available
    Item
    MOLECULAR ANALYSIS OF KERATINOCYTES WHICH DERIVED FROM MOUSE EMBRYONIC STEM CELLS
    Vatansever, HS; Turkoz-Uluer, E; Aydede, H; Ozbilgin, MK
  • No Thumbnail Available
    Item
    The roles of Transforming growth Factor Type β3(TGF-β3) and mast cells in the pathogenesis of scleroderma
    Ozbilgin, MK; Inan, S
    Scleroderma is a connective tissue disorder characterised by excessive accumulation of collagen in the skin and internal organs. The most likely explanation for this process is local activation of collagen synthesis from fibroblasts. Our intention was to elucidate whether TGF-beta(3) and mast cells play a pathogenic role in abnormal connective tissue formation in scleroderma. In this study, skin biopsies from 20 patients with scleroderma and five from healthy individuals were studied by an indirect immunoperoxidase technique to determine the immunoreactivity of TGF-beta(3) in the dermis. In addition, skin samples were stained with toluidine blue to count the number of mast cells in scleroderma, and tissues were examined under the electron microscope to evaluate the ultrastructural changes. Increased TGF-beta(3) immunoreactivities were detected in the dermis in the patient's skin, suggesting the presence of a subpopulation responsible for the increased collagen production. Mast cell counts in the skin of patients with scleroderma were significantly greater (19.2 +/- 4.1/unit) than those of normal controls (4.4 +/- 1.2/unit). Ultrastructural observations indicated that there is a close relationship between the mast cells and fibroblasts. These results suggest that fibrosis in scleroderma could evolve through the activation of fibroblasts and the regulatory mechanisms that appear to modulate the behavior of these cells with respect to collagen production.
  • No Thumbnail Available
    Item
  • No Thumbnail Available
    Item
    Keratinocytes derived from embryonic stem cells induce wound healing in mice
    Uluer, ET; Vatansever, HS; Aydede, H; Ozbilgin, MK
    The skin plays an important role in defending the body against the environment. Treatments for burns and skin injuries that use autologous or allogenic skin grafts derived from adult or embryonic stem cells are promising. Embryonic stem cells are candidates for regenerative and reparative medicine. We investigated the utility of keratinocyte-like cells, which are differentiated from mouse embryonic stem cells, for wound healing using a mouse surgical wound model. Mice were allocated to the following groups: experimental, in which dressing and differentiated cells were applied after the surgical wound was created; control, in which only the surgical wound was created; sham, in which only the dressing was applied after the surgical wound was created; and untreated animal controls with healthy skin. Biopsies were taken from each group on days 3, 5 and 7 after cell transfer. Samples were fixed in formalin, then stained with Masson's trichrome and primary antibodies to interleukin-8 (IL-8), fibroblast growth factor-2 (FGF-2), monocyte chemoattractant protein-1 (MCP-1), collagen-1 and epidermal growth factor (EGF) using the indirect immunoperoxidase technique for light microscopy. Wound healing was faster in the experimental group compared to the sham and control groups. The experimental group exhibited increased expression of IL-8, FGF-2 and MCP-1 during early stages of wound healing (inflammation) and collagen-1 and EGF expression during late stages of wound healing (proliferation and remodeling). Keratinocytes derived from embryonic stem cells improved wound healing and influenced the wound healing stages.
  • No Thumbnail Available
    Item
    Analysis of transferred keratinocyte-like cells derived from mouse embryonic stem cells on experimental surgical skin wounds of mouse
    Vatansever, HS; Uluer, ET; Aydede, H; Ozbilgin, MK
    Autologous/allogenic skin grafts constituted from differentiated adult or embryonic stem cells can be used in treatment of skin disorders. In our study we aimed to differentiate keratinocytes from mouse embryonic stem cells and the transfer of viable keratinocyte-like cells to a model of surgical skin wound of mouse. Embryoid bodies, derived from mouse embryonic stem cells, were cultured on basement membrane matrix with added BMP-4 for 10 days. The identification of differentiated keratinocyte-like cells was done by detection of cytokeratin-8 and cytokeratin-14 localization using an indirect immunoperoxidase technique and transmission electron microscopy evaluation. Distribution of BrdU, cytokeratin-8 and cytokeratin-14 were evaluated using an indirect immunoperoxidase technique from the experimental (dressing including BrdU labelled cells applied after the surgical wound was created on mouse), control (only the surgical wound was created on mouse) and sham (only the dressing applied after the surgical wound was created on mouse) in groups after 3, 5 and 7 days. Immunohistochemically and ultrastructurally, cells derived from mouse embryonic stem cells were similar to differentiated keratinocyte-like cells. Differentiated keratinocyte-like cells were demonstrated by positive BrdU, cytokeratin-8 and cytokeratin-14 staining after transfer to the wound area. In the experimental group wound healing was better after transferring differentiated keratinocytes when compared to the sham and control groups. In vivo continuity and usability of derived cells are very important issues. In wound repair mechanisms, keratinocyte-like cells could provide positive effects during the wound healing and could be used in clinical treatments of wound repair process. (C) 2012 Elsevier GmbH. All rights reserved.
  • No Thumbnail Available
    Item
  • No Thumbnail Available
    Item
    Effect of angiotensin-converting enzyme-inhibiting therapy on the expression of vascular endothelial growth factor in hyperstimulated rat ovary
    Ozcakir, HT; Giray, SG; Ozbilgin, MK; Inceboz, US; Caglar, H
    Objective: To determine the effect of angiotensin-converting enzyme-inhibiting therapy on the expression of vascular endothelial growth factor (VEGF) in the hyperstimulated rat ovary. Design: Experimental study. Setting: University animal research laboratory. Animal(s): Thirty Wistar albino adult female rats were studied; 20 rats were stimulated with gonadotropins (groups 1 and 2), and 10 were controls (group 3). Ten of the stimulated rats received additional treatment with enalapril (group 2). Intervention(s): At the end of the treatment period, rat ovaries were subjected to immunohistochemical staining with anti-VEGF antibodies. Main Outcome Measure(s): VEGF staining intensity was graded semi quantitatively, and the H-score was calculated by light microscopic examination of the groups. Result(s): VEGF expression was found to be significantly higher in the endothelium and stroma in groups 1 and 2 compared with group 3. Although VEGF immunoreactivity was lower in the stimulation regimen plus enalapril group compared with the stimulation regimen-only group, the difference was insignificant. Conclusion(s): Enalapril does not seem to have a significant effect on VEGF expression in the hyperstimulated rat ovary. Because angiotensin 11 exerts its multiple actions via specific receptors, there may be other factors, such as a receptor blockade, that contribute to the VEGF expression. (C) 2004 by American Society for Reproductive Medicine.
  • No Thumbnail Available
    Item
    Immunohistochemical detection of transforming growth factor-α, epidermal growth factor, and vascular endothelial growth factor expression in hyperstimulated rat ovary
    Ozcakir, HT; Giray, SG; Ozbilgin, MK; Uyar, Y; Lacin, S; Caglar, H
    Objective. The aim of the present study is to figure out the immunohistochemical expression of transforming growth factor-alpha (TGF-alpha), epidermal growth factor (EGF), and vascular endothelial growth factor (VEGF) in hyperstimulated rat ovaries. Methods. Twenty Wistar-Albino adult female rats (250-300 g) were taken into the study. The animals were randomly divided into two groups, each containing 10 rats: (i) stimulation group and (ii) control group. In the stimulation group, a stimulation regimen was administered to induce follicular maturity and ovarian hyperstimulation syndrome (OHSS) at the end using a 30-IU follicle-stimulating hormone that was administered subcutaneously for 4 consecutive days, followed by a 30-IU human chorionic gonadotropin on day 5 to induce ovulation. The rats, in the control group, received 0.2 ml of 0.9% NaCl for 5 consecutive days to mimic the conditions of the study animals. At the end of the treatment period, all rats underwent ovariectomy and the sections of ovaries were stained for the TGF-alpha, EGF, and VEGF. Results. The expression of TGF-alpha, EGF, and VEGF in the endothelium, the stroma, the granulosa cells, and the corpus luteum was found to be significantly higher in the stimulated group, compared to that in the control group ( p < 0.05). Conclusion. TGF-alpha, EGF, and VEGF are found to have increased in the hyperstimulated ovaries and this finding seems to be involved in the OHSS pathogenesis.
  • No Thumbnail Available
    Item
    POMC expression of the urothelium of the urinary bladder of mice submitted to pelvic radiation
    Ozbilgin, MK; Aktas, C; Temel, M; Önal, T; Uluer, ET; Vatansever, HS; Kurtman, C
    Objective: Patients who have had pelvic radiotherapy as part of their cancer therapy may develop subsequent urinary bladder injury. The acute changes that the urothelium undergo after radiation are known, but the healing mechanism of the urothelium of the urinary bladder after pelvic radiotherapy is not clearly understood. Proopiomelanocortin (POMC) peptides, which have immunomodulatory effects, are produced locally in sites outside of the central nervous system. This study aims to determine the role of POMC expression in the urothelium during radiation injury. Methods: Twenty-four male Swiss Albino mice were divided into four groups. A single-fractioned 10 Gy of ionizing radiation was applied to the pelvic zone of all mice with Cobalt-60 radiotherapy. The first group 1, which consisted intact animal and not irradiated was the control group, and the second, third, and fourth groups were euthanized after 24 h (Group 2), 48 h (Group 3), and 7 days (Group 4) after irradiation. All bladders were prepared for histochemical analysis using hematoxylin eosin (H&E) and immunohistochemical analysis using anti-POMC antibody. Results: No morphological differences were seen in all the group samples stained with H&E. POMC expression of the urothelium of bladder tissue samples shows different staining levels. Group 1 (96.7 +/- 7.68), Group 2 (88.3 +/- 8.04), and Group 3 (85.10 +/- 10.9) were very weakly stained, but the POMC immunoreactivity of Group 4 (113.0 +/- 12.8) was observed to be strong. Conclusion: Expression of POMC from urothelium seems to prevent bladder damage from radiation supplying differentiation and restoration of the urothelium.
  • No Thumbnail Available
    Item
    Influence of Radiation Exposure During Radiotherapy Evidence for the Increase of Versican and Heparin-Binding EGF-like Growth Factor Concentrations
    Ozbilgin, MK; Aktas, C; Uluer, ET; Buyukuysal, MC; Gareveran, MS; Kurtman, C
    OBJECTIVE: To investigate the reaction of versican and heparin-binding EGF-like growth factor (HB-EGF) molecule concentrations to acute radiation exposure in normal bladder and rectal tissue samples in order to gain more insight into the effects of cancer radiotherapy. STUDY DESIGN: Four groups with 6 male adult Swiss Albino mice per group were investigated. The mice bladder and rectum tissue samples were subjected to a 10-Gy single-dose radiation exposure in the pelvic region with a Co-60 teletherapy device and investigated 1, 2, and 7 days after radiation exposure, with 1 reference group which was not exposed to radiation. RESULTS: In the immunohistochemical examination of the tissue samples with anti-versican and anti-HB-EGF primary antibodies was observed a statistically significant increase 7 days after radiation exposure. CONCLUSION: The observed increase of versican and HB-EGF concentrations in the normal tissue matrix after radiation exposure may play a role in the side effects of radiotherapy.
  • No Thumbnail Available
    Item
    Calcitonin expression of high endothelial venules during lymphocyte migration in human pharyngeal tonsil
    Ozbilgin, MK; Kirmaz, C; Yüksel, H; Kurtman, C; Kaya, M
    The migration routes of lymphocytes through high endothelial venules (HEVs) of control and hypertrophic pharyngeal tonsil (HPT) tissue sections were investigated by immunohistochemistry using the expression of a hormone [calcitonin (CT)] and two calcium-dependent endothelial adhesion molecules (E-selectin and P-selectin), as well as electron microscopy. A marked increase in CT-specific staining was observed in the endothelial cells of HE V in the HPT group compared to the control group. Expressions of E-selectin and P-selectin on HEVs of control group were faint, when compared to the strong expression of these selectins on HEVs of HPT. Electron microscopically, we demonstrated that lymphocytes transmigrated through HEV and observed the close membranous contact between endothelial cells and lymphocytes during this process. We speculate that increasing CT during inflammation may be important for lymphocyte migration through the HEVs via controlling the expression of E-selectin and P-selectin.
  • No Thumbnail Available
    Item
    PTX3 levels in murine pulmonary parenchymal tissues are correlated with radiation-induced injuries
    Sarper, B; Ozbilgin, MK; Gumustepe, E; Gencur, S; Karaman, GZ; Kilicaslan, P; Kurtman, C
    Background: Pentraxins (PTX) play key roles in innate immunity and inflammatory responses. An increase in PTX3 levels may be a marker of early radiation injury in the lung. Thus, we aimed to determine the effect of radiation on PTX3 expression in a lung injury mouse model. Materials and Methods: Twenty-four 6-8-week-old mice were divided into 4 groups, one control (group 1) and three experimental groups (groups 2-4) irradiated with 6 MV photons and 5 Gy in a single fraction. Groups 2, 3, and 4 were sedated and euthanized 24, 72, and 168 h after radiation, respectively. The right lung middle lobe was then removed for histochemical examination and immunostaining for PTX3 expression, which was evaluated semiquantitatively using H-SCORE analysis. Kolmogorov-Smirnov and Kruskal Wallis one-way analysis of variance were used for statistical analysis. Results: Immunohistochemistry of lung tissue samples showed different PTX3 expression levels across the four groups. Group 1 showed weak staining (232.50 +/- 9.501), while group 2 (301.50 +/- 7.472) and group 3 (283.50 +/- 7.090) showed strong immunoreactivity. Group 4 showed moderate PTX3 immunoreactivity (271.50 +/- 10.013). Moreover, H-score values between control and early radiation groups were statistically significant (group 1 vs. group 2, p < 0.001; group 1 vs. group 3, p = 0.002). Conclusion: PTX3 levels may be an early marker for long-term radiation effects. Our study provides insights into the pathological processes of pulmonary inflammation and acute radiation injury, and may provide novel therapeutic strategies for controlling pulmonary inflammation without eliciting radiation injury.
  • No Thumbnail Available
    Item
    Effects of Cyclooxygenase on the Urothelium of the Urinary Bladder of Mice Exposed to Pelvic Radiation
    Ozbilgin, MK; Onal, T; Ozcan, C; Temel, E; Aktas, C; Gareveran, MS; Uluer, ET; Limn, S; Kurtman, C
    Objective: To determine the role of cyclooxygenase (COX) expression in the urothelium of the urinary bladder during radiation injury caused by pelvic radiotherapy for cancer therapy. Study Design: Twenty-four male Swiss Albino mice were separated into 4 groups. The first group was the control group (Group 1) and the second, third, and fourth groups were euthanized after 24 hours (Group 2), 48 hours (Group 3), and 7 days (Group 4), respectively. A single-fractioned 10 Gy of ionizing radiation was applied to all mices pelvic zone with Co-60. Bladders were removed completely from the pelvic region. Histochemical analysis using hematoxylin and eosin and immunohistochemical analysis using anti-COX-1 and COX-2 antibodies were performed on tissue samples. The immunoreactivities of the urinary bladder were quantified using H-score measurement, and statistical comparison was performed. Results: In the immunohistochemical examination the COX-1 immunoreactivities were found to be higher in the urothelium of the bladder in the radiation exposed groups than in the normal control group (group 1) (p<0.005). Additionally, high immunoreactivity of COX-2 molecule was established in groups 2, 3, and 4 of radiation groups as compared to group 1 (p<0.005) in examination of the urothelium. COX-1 and COX-2 immunoreactivities in the submucosa were detected higher in group 4 than in the other groups (p<0.005). Conclusion: COX-1 and COX-2 expressions in the urothelium and subepithelium of the urinary bladder were investigated in mice during the acute radiation response. The expression of COX-1 and COX-2 in the urothelium seems to prevent bladder damage from radiation, supplying differentiation and restoration of the urothelium.