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Browsing by Publisher "ELSEVIER GMBH"

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Effects of ocreotide on intestinal mucosa in rats with portal hypertensive enteropathy
(ELSEVIER GMBH) Aydede, H; Vatansever, HS; Erhan, Y; Ilkgül, O
To clarify the effects of long-term ocreotide (a long-acting somatostatin analogue) treatment on mucosal changes in a rat model of portal hypertensive enteropathy, groups of mate Swiss albino rats (n = 15 each) were randomly assigned to one of three treatment arms. These were: sham laparotomy+twice daily subcutaneous saline 0.5mL (Group 1); portal hypertension induction+twice daily subcutaneous saline 0.5 mL (Group 2); and portal hypertension induction+subcutaneous ocreotide 100 mu g/kg/12h (Group 3). After 12 weeks of treatment, jejunal and ilea( tissue specimens were obtained and evaluated histopathologically (villus/crypt ratio, mean diameter of dilated vessels, mucosal edema, and fibromuscular proliferation in the lamina propria) and immunohistochemically (vascular endothelial growth factor (VEGF), von Willebrand factor (F8), and cluster of differentiation 34 (034) [abetting). In jejunal. specimens, the villus/crypt ratio was markedly lower in Group 2 (2.38 +/- 0.46 mu m) than in Group 1(5.07 +/- 2.25 mu m) or Group 3 (4.97 +/- 2.19 mu m); mean diameter of dilated vessels was markedly higher in Group 2 (43.30 +/- 5.71 mu m) than in Group 1 (33.53 +/- 4.00 mu m) or Group 3 (36.76 +/- 3.96 mu m); mucosal edema and fibromuscular proliferation were universally absent in Group 1 when compared with the other groups. There were statistically significant differences (p<0.05) between Groups 1 and 2 for villus/crypt ratio, mean diameter of dilated vessels, VEGF immunolabelling intensity, and CD34 immunolabelling intensity; between Groups 1 and 3 for mean diameter of dilated vessels, VEGF immunolabelling intensity, and CD34 immunolabelling intensity; and between Groups 2 and 3 for villus/crypt ratio, mean diameter of dilated vessels, and VEGF immunolabelling intensity. In ileal. tissue specimens, the villus/crypt ratio was markedly lower in Group 2 (5.51 +/- 0.67 mu m) than in either Group 1 (7.19 +/- 2.18 mu m) or Group 3 (7.62 +/- 2.58 mu m); mean diameter of dilated vessels was markedly higher in Group 2 (46.36 +/- 4.77 mu m) than in either Group 1 (36.43 +/- 4.57 mu m) or Group 3 (41.31 +/- 4.70 mu m); white mucosal edema was absent in Group 1, it was present in Group 2 and Group 3; and fibromuscular proliferation was universally absent. There were statistically significant differences (p<0.05) between Groups 1 and 2 for villus/crypt ratio and mean diameter of dilated vessels; between Groups 1 and 3 for mean diameter of dilated vessels; and between Groups 2 and 3 for villus/crypt ratio, mean diameter of dilated vessels, and VEGF immunolabelling intensity. Together, these findings indicate that ocreotide treatment ameliorates histomorphological changes in a rat model of portal hypertensive enteropathy. (C) 2008 Elsevier GmbH. All rights reserved.
Reflection and transmission properties of a graphene-dielectric-thin resistive layer structure in the THz range
(ELSEVIER GMBH) Oguzer, T; Kuyucuoglu, F
We studied two-dimensional planar dielectric slab, sandwiched by graphene and thin resistive layer from two sides. Problem geometry is illuminated by a H-polarized electromagnetic plane wave from upper side. It is expected to observe the reflection and transmission performance of such a composite slab geometry depending on the electrical and geometrical parameters. We used the local reflection and transmission coefficients method to determine the overall performance. It is seen that the proper selection of the electrical resistivity of the thin resistive layer reduces the reflection from lower boundary of slab and the electrical thickness becomes less important for high THz range. Then, the geometry turns to be an air-dielectric interface. This is a novel finding and completely different from the pure dielectric slab without coatings which has frequency dependent characteristics. Also higher reflections are observed due to the higher conductivity of graphene in the low THz range. Furthermore, a sample finite plate is constructed in a same manner and it is modeled by using CST software. Presented method using equivalent 2D profile model and CST results are compared and very good consistency is observed. In both cases, the reflection can be controlled with the chemical potential at low THz range and the selection of the relative permittivity of the dielectric material determines the reflectance level at higher THz scale. We demonstrate these statements in the numerical results section for various problem parameters and angle of incidence.
Improving radiation performance of the cylindrical dielectric reflector sandwiched by thin resistive layer illuminated by a complex line source
(ELSEVIER GMBH) Kuyucuog, F; Og, T
We studied two-dimensional (2-D) thin dielectric parabolic reflector, sandwiched by thin resistive layer from both sides. It is illuminated by an E-polarized electromagnetic plane wave from front side. It is expected to observe the radiation performance of such a composite reflector depending on the electrical and geometrical parameters. We applied two-sided generalized boundary conditions which are modified for a thin multilayer structure. The electromagnetic boundary value problem is formulated and it finally produced a set of two coupled singular integral equations (SIEs). They are handled with the analytical regularization method based on the Riemann-Hilbert Problem solution. The final numerical results are in the Fredholm second-kind matrix equation form and any desired accuracy can possibly be obtained. Also the solution procedure guarantees the convergence. It is observed that the proper selection of the electrical resistivity of the thin resistive layer produces wider bandwidth in the aperture efficiency and the directivity variation approaches to the perfect electric conductor (PEC) reflector case for higher dielectric constants. This selection can increase the allowable frequency band in the applications by coating dielectric layer from both sides. We demonstrate these statements in the numerical results section in the microwave frequency range.
Significance of apoptosis related proteins on malignant transformation of ovarian tumors: A comparison between Bcl-2/Bax ratio and p53 immunoreactivity
(ELSEVIER GMBH) Zeren, T; Inan, S; Vatansever, HS; Sayhan, S
In this study, we compared the immunoreactivities of Bcl-2, Bax and p53 proteins in ovarian tumors and related the immunohistochemical findings to the histological type of the tumors. Formalin-fixed, paraffin wax-embedded tissue sections from 40 patients who had serous-mucinous borderline tumors and serous-mucinous adenocarcinoma of the ovary (n = 10 each) were stained with hematoxylin-eosin (H&E). After histopathological examination, serial sections were stained immunohistochemically with primary antibodies to Bcl-2, Bax and p53 using an avidin-biotin-peroxidase method. A semi-quantitative grading system was used to compare the immunohistochemical staining intensities. The nuclear DNA fragmentation of apoptosis was determined using TUNEL method. As a result of immunohistochemical staining, increased immunoreactivity of Bcl-2 was observed in adenocarcinomas when compared to borderline tumors (P < 0.001). Strong immunoreactivity of Bcl-2 and mild immunoreactivities of Bax and p53 were detected in ovarian adenocarcinomas. There were no significant statistical differences in the immunoreactivity of Bax among the histological type of ovarian tumors. Whereas a balance was observed between the immunoreactivities of Bcl-2 and Bax in the borderline cases, and this balance was strongly changed toward the anti-apoptotic Bcl-2 protein in patients with adenocarcinoma. TUNEL staining of 'sections indicated apoptotic cells in the serous borderline tumors were about 8-fold higher than in the serous adenocarcinoma. The results of this study on apoptosis-related factors might help to develop novel protective and therapeutic approaches, such as isofiavonoids and isothiocyanates, which were associated with decreased Bcl-2/Bax ratio, against the malignant epithelial ovarian tumors. (C) 2014 Elsevier GmbH. All rights reserved.
Immunolocalization of VEGF, VEGF receptors, EGF-R and Ki-67 in leiomyoma, cellular leiomyoma and leiomyosarcoma
(ELSEVIER GMBH) Sanci, M; Dikis, C; Inan, S; Turkoz, E; Dicle, N; Ispahi, C
Angiogenic factors, such as vascular endothelial growth factor (VEGF), its receptors and epidermal growth factor receptor (EGF-R), are involved in increased progression in many carcinomas. The aim of this study was to investigate the role of angiogenesis and immunolocalization of VEGF, its receptors, EGF-R and Ki 67 in leiomyomas and leiomyosarcomas using an indirect immunohistochemical method. Samples from patients with leiomyoma, cellular leiomyoma and cellular leiomyosarcoma (n=20 per group) were fixed in 10% formalin and processed using routine paraffin protocols. Following initial histological analysis, samples were immunostained with primary antibodies for VEGF, VEGFR-1, VEGFR-2, EGF-R and Ki-67 using an indirect avidin-biotin peroxidase method. Immunostaining intensities were evaluated as mild, moderate or strong and a semi-quantitative method (H-Score) was used to compare the samples. While mild/moderate EGF-R immunostaining and moderate immunostaining for VEGF and its receptors were observed in samples of leiomyomas, much less immunoreactivity was observed in cellular leiomyomas. All immunoreactivities and immune-stained cells increased in leiomyosarcomas. When scores of intensity and percentage of positive staining cells were compared, all immunoreactivities were shown to be significantly increased in leiomyosarcomas compared to leiomyomas. These results suggest that in leiomyosarcoma, angiogenic factors, such as VEGF, its receptors and EGF-R, may be involved in tumor angiogenesis. Active tumor cells can trigger angiogenesis, interaction with surrounding tissue and in the tissue itself initiating angiogenic activity. Angiogenic growth factors play an important role and induce malignant transformation through both autocrine and paracrine mechanisms. Anti-angiogenic agents may provide a novel therapeutic approach for the treatment of leiomyosarcoma. (C) 2010 Elsevier GmbH. All rights reserved.
The role of ATP sensitive K+ channels and of nitric oxide synthase on myocardial ischemia/reperfusion-induced apoptosis
(ELSEVIER GMBH) Gok, S; Vatansever, S; Vural, K; Sekuri, C; Izanli, A; Tezcan, A; Cilaker, S
During ischemia, ATP-sensitive K+ channels (KATP channels) open, and this triggers necrotic processes and apoptosis. In this study, we investigated whether selective sarcoplasmic and mitochondrial KATP channel blockers affected myocardial apoptosis and nitric oxide synthase (NOS) activity in a rat model of myocardial ischemia/reperfusion in vitro. Isolated rat hearts were subjected to 30 min of coronary artery occlusion followed by 30 min of reperfusion. A selective sarcKATP channel blocker, HMR1098 and a selective mitoKATP channel blocker, 5-hydroxydecanoate, were added to the perfusion fluid 10 min before occlusion. Myocardial apoptosis was detected immunohistochemically using the TUNEL method. Myocardial inducible NOS (iNOS) and endothelial NOS (eNOS) were determined immunohistochemically. In control hearts, apoptosis induction was associated with a greater immunoreactivity of iNOS than eNOS. Treatment with HMR1098, at a concentration of 3 mu mol/l, significantly reduced the TUNEL-positive cardiomyocytes and this was associated with decreased iNOS and increased eNOS immunoreactivity. When this drug was administered at a higher concentration, at 30 mu mol/l, a more marked reduction in apoptosis was observed but, in contrast to the effects observed at the lower drug concentration, eNOS immunoreactivity was almost completely abolished while iNOS was strong. Moreover, ischemia-induced cardiac dysfunction (e.g. contractile force and recovery of coronary flow) was increased by the higher concentration of HMR 1098. In hearts treated with 5-hydroxydecanoate, myocyte apoptosis was slightly reduced, and this was associated with an almost equal increase in both iNOS and eNOS immunoreactivity. These findings suggest that iNOS appears to be more important than eNOS in the reduction of apoptosis. However, the further inhibition of apoptosis by the higher concentration of HMR 1098 was associated with poorer cardiac function. (C) 2006 Elsevier GmbH. All rights reserved.
Thermoluminescence kinetic parameters of yttrium niobate
(ELSEVIER GMBH) Ege, A; Özkan, A
Yttrium niobate (YNbO4) phosphorus produced using the solid-state technique by sintering at 1200 degrees C investigated for thermoluminescence (TL) kinetics after irradiated with ultraviolet radiation (UV). The TL glow curve of UV irradiated yttrium niobate phosphorus recorded with a heating rate of 2 Ks(-1) exhibited glow peaks at 366 and 424 K. The TL kinetic parameters belonging to main glow peak (424 K) of yttrium niobate phosphor, namely trap energy (E), frequency factor (s) and kinetic order (b) were investigated using Various Heating Rates (VHR), Computerized Glow Curve Deconvolution (CGCD), and Chen's Peak Shape (PS) methods after exposure to UV radiation. Trap energies of the phosphor by all methods were calculated as 1.09 eV. The frequency factors of the phosphor by CGCD, VHR and Chen's PS methods were obtained as 0.96 x 10(12) s(-1), 1.38 x 10(12) s(-1) and 0.98 x 10(12) s(-1), respectively. The results attained by all methods are discussed and compared.
Development an optical sensor using lyotropic cholesteric liquid crystals for the detection of toxic gases
(ELSEVIER GMBH) Kemiklioglu, E; Gurboga, B; Tuncgovde, EB
In the current study, a lyotropic cholesteric liquid crystal (ChLC) based sensor for the identification of vapors of polar (toluene and phenol) and apolar (1,2 dicholoropropane) toxic gases was investigated. The lyotropic ChLC sample including cholesteryl oleyl carbonate, cholesteryl pelargonate, and cholesteryl benzoate was supported on the chemically modified glass surfaces as an optical sensor for the detecting of these toxic gases vapors. The glass surfaces were modified by coating Dimethyloctadecyl [3-(trimethoxysilyl) propyl] ammonium chloride (DMOAP). The optical signal generated by the incorporation of different toxic gases vapors in the lyotropic ChLC layers which disturbs the pitch length. These toxic gases were evaporated at different temperatures and the exposure time was differentiated. Increasing solvent evaporation temperature lead a shift in the wavelength maximum to smaller wavelengths which can be observed by a naked eye.
Novel inflammatory targets for immunotherapies in pediatric patients with trichotillomania
(ELSEVIER GMBH) Kutuk, MO; Tufan, AE; Kilicaslan, F; Mutluer, T; Gokcen, C; Karadag, M; Yektas, C; Kandemir, H; Buber, A; Aksu, GG; Topal, Z; Giray, A; Celik, F; Acikbas, U; Kutuk, O
Immune dysregulation may be important in the etiology of obsessive-compulsive and related disordersandbody-focusedrepetitivebehaviors, such as Trichotillomania (TTM). The role of inflammation and inflammatory markers in TTM has received relatively little attention. This study was aimed to determine the expression levels of inflammatory markers (i.e. IL-1 beta, IL-1 alpha, IL-4, IL-6, IL-17, TNF-alpha and TGF-5) in peripheral blood mononuclear cells of children with TTM and healthy controls and to evaluate their association with clinical variables. Seventy-seven patients with TTM and 107 healthy controls were enrolled in the study. Peripheral blood was collected in standardized conditions. The mean age of patients and controls did not differ significantly (10.8 +/- 4.4 and 12.0 +/- 3.2 years; respectively). The majority of patients with TTM and controls were females (n = 55, 71.4 % and n = 55, 51.4 %; respectively); with a greater preponderance of females among TTM. Patients with TTM had significantly elevated expression levels of TNF-alpha, IL-6 and IL-17 compared to controls. However, the expression level of IL-4 was significantly reduced in TTM patients compared to controls. Accordingly, we found a proinflammatory state in TTM and those findings may suggest novel treatment options for TTM and further, crossdisciplinary studies focusing on neuro- inflammation in TTM conducted on larger samples are needed.
Estimating elasticity modulus of the piezo ceramic disc (PCD) using basic mathematical modelling
(ELSEVIER GMBH) Parali, L; Sari, A; Malgaca, L; Pechousek, J; Latal, F
The objective of this paper is to determine a mathematical modelling of piezoceramic disc vibration using a single degree freedom mechanical model, with estimation of its elasticity modulus. The experimental vibration displacement values of piezo ceramic disc have been achieved utilizing the swept-sine signal excitation following the peak values in the signal response measured by the laser Doppler vibrometer. Consistency between the mathematical modelling and experimental values have been observed from 97 to 80% between excitation amplitudes of 0.5 and 3.5 V when the mathematical modeling of piezo ceramic disc is normally taken into consideration with a linear working range. The results obtained from experimental studies on resonance frequency are in a compliance with reference value declared by producer of the piezo ceramic disc.
Immunolocalization of VEGF, VEGFR-1 and VEGFR-2 in lung tissues after acute hemorrhage in rats
(ELSEVIER GMBH) Ekerbicer, N; Tarakci, F; Barut, T; Inan, S
In treatment of hypovolemia it is important to reestablish normal tissue hemodynamics after fluid resuscitation. Vascular endothelial growth factor (VEGF) and VEGF receptors (VEGFR) have been identified as important in many physiological and pathological, processes. In this study, we aimed to investigate the histophysiological effects of VEGF, VEGFR-1 (flt-1) and VEGFR-2 (KDR/flk-1) in resuscitation with different plasma substitutes on lung tissues after acute hemorrhage in rats. Mate Sprague-Dawley rats (n = 25) were used in this study. The left femoral. vein and artery were cannulated for the administration of volume expanders and for direct measurement of mean arterial blood pressure (MAP) (Power-Lab) and heart rate (HR). Fifteen rats were bled (5 ml/10 min) and infused (5 ml/5 min) with one of three randomly selected fluids: (a) dextran-70 (Macrodex); (b) gelatin (Gelofusine); or (c) physiological saline (PS, 0.9% isotonic saline) solutions. Five rats were bled and none were infused (hypovolemia group) and five rats were untreated as the control group. At the end of the experiment, rats were sacrificed and lung tissues were removed for routine processing and paraffin wax embedding. Sections of tissue were stained with hematoxylin and eosin (H&E) and selected blocks were then prepared for indirect immunohistochemical labeling for anti-VEGF, anti-VEGFR-1 and anti-VEGFR-2 primary antibodies. It was observed that both MAP and HR decreased parallel to blood withdrawn in this time interval. The MAP and HR were restored in the following periods. In the control rats, positive immunoreactivity of VEGF and its receptors (VEGFR-1 and VEGFR-2) were detected in respiratory epithelial, cells, respiratory and vascular smooth muscle cells, alveolar cells and endothelial cells. White strong immunoreactivities of VEGF and VEGFR-1 were observed in the hypovolemia group, only moderate immunoreactivity of VEGFR-2 was seen in this group. Moderately strong immunolabeling of VEGF and VEGFR-1 were observed in the dextran-70, gelatin and PS resuscitated groups, whereas only weak immunolabeling of VEGFR-2 was observed in these groups. In summary, the vascular protecting effects of these factors were observed with fluid resuscitation, contributing to the pathophysiological changes seen in hypovolemia. (C) 2007 Elsevier GmbH. All rights reserved.
A new approach to design multi section wideband transmissive absorber using thin resistive sheets and dielectric slabs
(ELSEVIER GMBH) Oguzer, T; Kuyucuoglu, F
A new design and analytical procedure are presented that greatly enhance the absorption bandwidth and absorptivity level with few dielectric layers without using the metallic ground plane. The performance of the proposed structure is beyond what is possible with Salisbury screen or Jaumann absorber. The performance improvement is obtained using the resistive sheets coated on the surface of each lossless dielectric slab. Reflected waves inside each dielectric layer are eliminated and input reflection coefficient can easily be written with the aid of binomial expansion without any approximation. So we can apply Binomial design and considerable improvement at the absorption level and bandwidth is realized by the selection of the resistive sheets with the critical resistivity values. Alternatively, we observed that transmission is inde-pendent from frequency and layer number and it can be controlled only by the initial and final layer's dielectric constants. Two cases are analyzed as air to air and air to dielectric. Absorptivity, transmittivity and reflectivity variations are presented versus frequency in 0-20 GHz band, in both cases. It is shown that choosing three layers backed with a final layer (epsilon rb=20) structure in air to air case gives absorptivity greater than 90% in 5.45-14.55 GHz band where fractional bandwidth is 91% at 10 GHz design frequency. The design is performed at normal incidence and also wide angular stability at a reasonable level is presented. CST Microwave Studio and AWR simulation programs are also used to prove the correctness of the proposed method.
Effects of levosimendan and dobutamine on experimental acute lung injury in rats
(ELSEVIER GMBH) Erbüyün, K; Vatansever, S; Tok, D; Ok, G; Turköz, E; Aydede, H; Erhan, Y; Tekin, I
The effects of levosimendan on acute lung injury induced by peritonitis and abdominal hypertension in the early stages of sepsis in rats were investigated. Twenty-four adult male Wistar rats were randomized into: (1) sham, (2) subjected to abdominal hypertension and peritonitis induced lung injury using cecal ligation and puncture, then treated by dobutamine, (3) subjected to abdominal hypertension and peritonitis induced lung injury using cecal ligation and puncture, then treated by levosimendan, and (4) controls subjected to abdominal hypertension and peritonitis induced lung injury using cecal ligation and puncture with no treatment. In the control and levosimendan groups, cecal ligation and puncture resulted in moderate IL-1 beta immunolabelling in lung tissue; marked IL-1 beta immunolabelling was demonstrated in the dobutamine group. TNF-alpha immunolabelling was negative in both the sham and levosimendan groups, but moderate and weak immunoreactivities were observed in the dobutamine and control groups, respectively. There were almost no TUNEL positive cells in the sham, but they were prominent in the control. TUNEL positive cells were significantly less in the levosimendan treated lungs when compared to control and dobutamine groups. Immunoreactivity of eNOS was stronger in the dobutamine group when compared with the levosimendan group. In addition, iNOS immunoreactivity was strongly detected in the control group; this immunoreactivity was less in the levosimendan group than the dobutamine group. In this experimental sepsis model, treatment with levosimendan had a marked effect on attenuating or decreasing apoptosis and inflammation in the lung. (C) 2008 Elsevier GmbH. All rights reserved.
The effect of Misoprostol, a prostaglandin E1 analog, on apoptosis in ischemia-reperfusion-induced intestinal injury
(ELSEVIER GMBH) Topcu, I; Vatansever, S; Var, A; Cavus, Z; Cilaker, S; Sakarya, M
The aim of this study was to investigate whether Misoprostol, a synthetic prostaglandin (PG) E1 analog, has any effect on the prevention of apoptosis in ischemia-reperfusion (I/R)-induced intestinal injury. Thirty adult mate Wistar albino rats were divided into three groups: group I = sham operated+satine; group II = I/R+saline; and group III = I/R+Misoprostol. Misoprostol. (50 mu g/kg/d) was administered as an intragastric meat for 3 days. The terminal ileum was collected for histological and biochemical. investigations. Apoptotic cells were detected by terminal deoxynucteotidyl transferase-mediated dUTP nick end-labetted (TUNEL) reaction. Immunohistochemical. analysis was performed to determine the distribution of inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS). Samples were also analyzed for matondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px). The number of TUNEL-positive cells was higher in group II when compared to the other two groups (p < 0.05). In group III this value was higher when compared to group I, but lower than group II (p<0.05). iNOS immunoreactivity was not detected in ileum sections of group I animals, but moderate immunoreactivity was seen in group II and mild immunoreactivity in group III. The immunoreactivity of eNOS was moderate in ileum sections of all three groups. In ileum tissue, MDA was found to be higher in group II compared to group I (p<0.05), but there was no difference in group III. SOD was not different between groups I and III, but was significantly higher in group II (p<0.05). In our experimental model of I/R-induced intestinal injury, apoptosis is induced in enterocytes, whereas Misoprostol decreases enterocyte apoptosis in this experimental model. Our results indicate that Misoprostol may play a key rote in the pathophysiologic events leading to failure of the intrinsic gut barrier defense mechanisms of intestinal epithelium. (c) 2007 Elsevier GmbH. All rights reserved.
The role of CAPE in PI3K/AKT/mTOR activation and oxidative stress on testis torsion
(ELSEVIER GMBH) Dilber, Y; Inan, S; Ercan, GA; Sencan, A
Ischemia reperfusion injury arises from testicular torsion resulting in a loss of spermatogenesis and significant germ cell apoptosis. This study evaluates the prooxidant/antioxidant effects of caffeic acid phenethyl ester (CAPE) through PI3K/AKT/mTOR signal pathways on testis torsion. A total of (28) male Wistar rats were divided randomly into 4 groups (n = 7 for each group):group A (sham) group,group B torsion/detorsion group, group C (saturation group, during four days of CAPE, one dose (10 mu mol/kg, i.p)) and group D (a single dose of CAPE 2 h after torsion and before detorsion). At the end of the study, unilateral orchiectomies were performed for measurements of MDA and 8OHdG levels, histopathologic and immunohistochemical and TUNEL apoptotic cell examination. Testicular torsion-detorsion led to a significant decrease in the mean values of the Johnsen's scores and a significant increase in the apoptotic cell values of group B. There were no significant differences between group D and group A. In addition, the MDA and 8OHdG levels increased significantly in group B. The MDA and 8OHdG values were lower in group D. However, the 8OHdG levels were higher in group C than the groups A and D. On the other hand, CAPE suppresses mTOR activation and reduces the apoptosis on ischemia/reperfusion damage in rat testis. These results demonstrate that CAPE suppresses mTOR activation and reduces the apoptosis on ischemia/reperfusion damage in rat testis. (C) 2015 Elsevier GmbH. All rights reserved.
The investigation of immunomodulatory effects of adipose tissue mesenchymal stem cell educated macrophages on the CD4 T cells
(ELSEVIER GMBH) Özdemir, RBÖ; Özdemir, AT; Sariboyaci, AE; Uysal, O; Tuglu, MI; Kirmaz, C
Mesenchymal stem cells (MSCs) are strong immunomodulatory cells investigated in numerous clinical studies on fatal pathologies, such as graft versus host disease and autoimmune diseases; e.g., systemic lupus erythematosus, Crohn's disease, and ulcerative colitis. Macrophages are one of the critical cells linking the innate and adaptive immune system, and it has been shown that MSCs can differentiate between pro-inflammatory M1 phenotype and anti-inflammatory M2 phenotype of macrophages. However, it has not yet been fully clarified whether these differentiated macrophages are functional. In this study, we compared the immunomodulatory effects on the CD4 T cells of M1, M2a and M2c macrophages with the macrophages that directly and indirectly cultured with MSCs. We analyzed the changes in CD14, CD64, CD80, CD163 and CD200R expression to evaluate macrophage phenotypes, and the changes in CD4, IFN-g, IL-4, IL-17a and FoxP3 expression to evaluate T helper subsets using the FACS method. The changes in IL-1b, IL-4, IL-10, IL-12p70, IL-17a and IFN-g in the media supernatants were analyzed using the Luminex method. We also performed WST-1 and Caspase-3 ELISA analyses to observe the proliferation and apoptosis status of the T cells. MSCs were found to differentiate macrophages into a distinctive phenotype, which was close to the M2c phenotype, but was not considered as an M2c cell due to the low expression of CD163, a characteristic marker for M2c. While MEM-D, MEM-ID and MSCs showed similar inhibitory effects on the Th2 and Th17 cells, the most significant increase in Treg cell frequencies was seen in MEM-D cells. Macrophages can alter their phenotypes and functions according to the stimuli from the environment. The fact that macrophages educated with MSCs suppressed the production of all the cytokines we evaluated even after the removal of MSCs suggests that these cells may be differentiated by MSCs into a suppressive macrophage subgroup. However, the Treg cell activation caused by direct interactions between MSCs and macrophage cells may be the most prominent observation of this study compared to previous work. As a result, according to our data, the interactions between MSCs and macrophages may lead to differentiation of macrophage cells into an immunosuppressive phenotype, and these macrophages may suppress the T lymphocyte subgroups at least as effectively as MSCs. However, our data obtained from in vitro experiments should be supported by future in vivo studies.
Cell surface glycosylation diversity of embryonic thymic tissues
(ELSEVIER GMBH) Balcan, E; Tuglu, I; Sahin, M; Toparlak, P
In the thymus, glycosylation status of many cell surface molecules changes during the thymocyte maturation and selection processes. In this study, we evaluated the glycosylation changes and possible relationships with programmed cell death in the thymic tissues from mouse embryos at the days 14 (E14), 15 (E15), 16 (E16), 17 (E17) and 18 (E18) of embryonic development. In order to determine glycosylation changes we used three different plant Lectins: peanut agglutinin (PNA), Moackia amurensis leucoagglutinin (MAL or MAAI) and Sombucus nigra agglutinin (SNA), which recognize core disaccharide galactose (1-3) N-acetylgalactosamine [Gal beta(1 -> 3)GalNAc], siatic acid linked (2 -> 3) to galactose [SA alpha(2 -> 3)Gal] and siatic acid linked to galactose [SA)alpha(2 -> 6)Gal] structures, respectively. Our lectin histochemistry and lectin blotting studies indicated that glycosylation pattern was modified in thymocytes at the embryonic developmental. stages analyzed. The immature cortical thymocytes were labeled by PNA, whereas medullary thymocytes were positive for MAL and SNA binding. Many medullary thymocytes exhibited alpha(2 -> 6)-linked siatic acid on their surface and this increased throughout the gestational stages. In the lectin blotting studies, different protein bands of various molecular weights were identified in thymocytes. Two of them were putatively identified as CD43 and CD45 glycoproteins. In addition, TUNEL (deoxynucleotdyltransferase-mediated dUDP nick end labeling) indicated that only PNA-positive cortical thymocytes were deleted in all embryonic stages. These results indicate that the glycosylation pattern was modified in thymocytes at all embryonic developmental stages, and these modifications can affect the T cell deletion, probably via the galectin-1 molecule in the embryonic thymus. (C) 2007 Elsevier GmbH. All. rights reserved.
A digital measurement system based on laser displacement sensor for piezoelectric ceramic discs vibration characterization
(ELSEVIER GMBH) Parali, L; Pechousek, J; Sabikoglu, I; Novak, P; Navarik, J; Vujtek, M
This study describes the innovative design of a digital measurement system based on a laser displacement sensor (LDS) as a vibrometer which is capable to measure a dynamic displacement response dependence on a stimulated vibration. The frequency response of a piezoelectric ceramic disc is obtained by processing the input/output signals obtained from the function generator and digital oscilloscope (digitizer) cards driven by a personal computer. Resonant frequencies of vibration are achieved utilizing the swept-sine signal excitation following the peak values in the signal response measured by LDS. The analogue signal from LDS controller represents directly a mechanical vibration of a piezoceramic disc. The test measurement results indicate that the system can distinguish resonance frequencies of piezoelectric ceramic discs up to 40 kHz with the resolution 1 Hz. Piezoelectric coefficient d(33) and its linearity along the excited voltage amplitudes have been calculated by the applied methods as a demonstration of a successful system concept. The results achieved are in compliance with the reference value declared by the manufacturer of the piezoceramic disc. (C) 2015 Elsevier GmbH. All rights reserved.
Effects of 5-fluorouracil and gemcitabine on a breast cancer cell line (MCF-7) via the JAK/STAT pathway
(ELSEVIER GMBH) Uluer, ET; Aydemir, I; Inan, S; Ozbilgin, K; Vatansever, HS
Aberrant activation of the JAK/STAT pathway may predispose to malignancy as a consequence of the deregulation of cell proliferation, differentiation or apoptosis such as in cancer of the blood, head and neck, and breast. In our study we aimed to investigate the effects of 5-fluorouracil (5-FU) and gemcitabine on a breast cancer cell line (MCF-7 cells) via the JAK/STAT pathway. Distribution of JAK1, JAK2, JAK3 and STAT2, STAT3, STAT4, STAT5 were evaluated on MCF-7 cells following gemcitabine and 5-FU treatment and in the absence of drug treatment by an indirect immunohistochemical method. It was observed that JAK1, JAK3, STAT5 and particularly STAT2 activation were more effective than the other JAK/STATs in breast cancer progression. Following treatment with 5-FU, JAK1 and STAT5 immunoreactivities were decreased in MCF-7 cells in comparison with both gemcitabine-treated and non-treated groups. These results suggest that the JAK/STAT pathway plays an important role in breast cancer pathogenesis and may be more affected after 5-FU treatment rather than gemcitabine. Drugs which block STAT5 may provide a novel therapeutic approach for the treatment of breast cancer. (c) 2011 Elsevier GmbH. All rights reserved.

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