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Öğe The effect of Nigella sativa oil against experimental allergic encephalomyelitis via nitric oxide and other oxidative stress parameters(C M B Assoc, 2005) Ozugurlu, F; Sahin, S; Idiz, N; Akyol, O; Ilhan, A; Yigitoglu, R; Isik, BReactive oxygen species (ROS) including nitric oxide (NO) are thought to be involved in inflammatory processes, exacerbating inflammation and tissue damage in multiple sclerosis (MS). The oil extracts of Nigella Sativa (N. sativa) has been known as an antioxidant and antiinflammatory agent. The aim of the present study was to investigate the hypothesis that N. sativa components provide protection against oxidative stress induced by experimental autoimmune encephalomyelitis (EAE) in rats. For this purpose, EAE was induced in rats by using guinea pig myelin basic protein (MBP) in Freud's adjuvant with addition of heat-killed M. Tuberculosis H37Ra to test this hypohesis. In study groups, N. sativa was given by oral gavage to the rats. Treatment of the rats with N. sativa inhibited ROS production induced by EAE showing diminished levels of MDA of both brain and medulla spinalis tissues. Although there was a significant decrease in brain NO level, there was an increase in medulla spinalis NO level after EAE induction in rats. N. sativa regulated tissue NO levels in some extend when applied together with EAE. When N. sativa was given alone to the rats, no changes were shown in brain, medulla spinalis, and serum oxidant/antioxidant parameters. In conclusion, N sativa may protect brain and medulla spinalis tissues against oxidative stress induced by EAE. In additon, N. sativa display its antioxidant and regulatory effects via inflammatory cells rather than the host tissue (brain and medulla spinalis) for EAE in rats.Öğe Effects of dominance, body mass index and age on grip and pinch strength(Ios Press, 2003) Ertem, K; Inan, M; Yologlu, S; Elmali, N; Harma, A; Sahin, S; Bora, AMeasurement of grip and pinch strength is an important component in hand evaluation. It assesses the patient's initial limitations and provides a quick reassessment of patient's progress throughout the treatment. This investigation was conducted to examine the effects of hand dominance, body mass index (BMI) and age on grip strength (GS) and pinch strength (PS) tasks. Subjects were 365 apparently healthy young male adults (19-33 years). No correlation was found between the BMI hand strength measures. Grip and pinch strength were measured instrumentally. The rule dominant hand (DH) is approximately 10% stronger than the nondominant hand (NDH) was found to be valid for left handed persons only (11.2%), otherwise these measures should be considered equivalent in both hands in clinical practice.Öğe Effects of halotane, sevoflurane and isoflurane anesthesia on neuromusculer blocking effect of rocuromum(Prof Sci Publ, 1999) Togal, T; Türköz, A; Sahin, S; Toprak, HI; Ersoy, MÖ[Abstract Not Available]Öğe Elimination of the coil shielding for MFE-reactors through a liquid-protected first-wall(King Fahd Univ Petroleum Minerals, 2002) Sahin, S; Sahinaslan, A; Sahin, HMThe idea of a protective, flowing, liquid zone to protect the first wall of a magnetic fusion energy (MFE) reactor from the direct exposure of the fusion reaction products is not new. This could extend the lifetime of the first wall to the lifetime of the fusion power plant, namely to 30 years. The present work discusses the possibility that such a liquid zone could lead also to the elimination of the magnetic coil shielding for WE reactors. Contrary to a related previous work, the liquid wall is now placed at the outermost periphery of the plasma chamber, in order to leave a greater space for the fusion plasma volume and consequently to lead to higher fusion power with the same plasma parameters. In this work, SS-304 type steel, SiC, and graphite are selected as structural materials. Different types of liquid coolant with tritium breeding capabilities (Flibe, Li17Pb83, natural lithium, all with natural lithium component) are investigated to protect the first wall from neutron- and bremsstrahlung-radiation and fusion reaction debris. The calculations are conducted for a power generation of 1GW(el) over 30 years of reactor operation with a thermodynamically conversion efficiency of 35 % leading to 2.857 GW(th) by a capacity factor of 100 %, The most important improvements through the placement of the protective liquid wall at the outer periphery in the new blanket can be cited as follows. Such a blanket: would in practice not necessitate extra shielding for superconducting coils around the fusion plasma chamber; would open the possibility of utilization of conventional stainless steel for fusion reactors due to the sufficiently low residual radioactivity in the structural materials after decommissioning of the plant. Research efforts and costs, involved in searching new alternative ceramic structural materials, such as SiC and graphite, based on unproven technology can be saved; and would make it possible to produce higher fusion power with a greater plasma volume.Öğe Maternal serum and amniotic fluid hydroxyproline levels in neural tube defects(Karger, 2003) Özyurt, H; Totan, A; Sahin, S; Kilinç, C; Sögüt, S; Akyol, ÖObjective: The present study was aimed to evaluate the alterations of maternal serum and amniotic fluid OH-proline levels in neural tube defects (NTD). Methods: 38 patients and 23 control subjects were selected from the patients followed up by the Departments of Genetics and Antenatal Care, Zekai Tahir Burak Women's Health, Education and Research Hospital. Amnion fluid and blood samples were synchronously obtained from NTD and control subjects. OH-proline levels were detected spectrophotometrically. Results: Amniotic fluid CH-proline levels were found to be increased in NTID patients compared to control subjects (p < 0.05). There was no statistically significant difference in serum OH-proline levels between the groups. Conclusion: The results showed an increase in amniotic fluid OH-proline levels in NTD compared to the control group. It may be suggested that the increased OH-proline levels reflect increased collagen turnover in NTD patients. Indeed, amniotic fluid OH-proline levels may be a candidate as an additional diagnostic parameter in NTD. Copyright (C) 2003 S. Karger AG, Basel.Öğe Midazolam in treatment of various types of seizures in children(Elsevier Science Bv, 1997) Yakinci, C; Müngen, B; Sahin, S; Karabiber, H; Durmaz, YMidazolam is a recently developed water-soluble benzodiazepine that shares anxiolytic, muscle relaxant, hypnotic and anticonvulsant actions with other members of this class. There are limited studies that midazolam can be used successfully to treat seizures in adults and children. In this study, 0.2 mg/kg intramuscular (IM) midazolam was administered to 11 children (eight boys and three girls), aged 3 days to 4 years (mean age 1.8 +/- 1.4 years), with seizures of various types. In all but one child, seizures stopped in 15 s-5 min after injection. No side effects were observed. These results suggest that IM administration of midazolam may be useful in a variety of seizures during childhood, especially in case of intravenous (IV) line problem. (C) 1997 Elsevier Science B.V.Öğe Neutron and gamma ray heating in the grazing incident liquid metal mirrors for laser inertial fusion energy power plants(Pergamon-Elsevier Science Ltd, 2002) Sahin, S; Sahinaslan, AA thin film of liquid metal can serve as final optics of a laser inertial fusion energy (IFE) power plant. Calculations of pulsed neutron and gamma-ray heating are presented for a grazing incident liquid metal mirror (GILMM) used for robust final optics of a laser IFE power plant. Different liquid films (Li, Na, Mg, Al, Si, K, Ga, Ag, Au, Pb, Bi and Flibe Li2BeF4) are considered at a distance of 30 in from a nominal 1 GJ fusion source as well as different substrate materials (SS-304 and SiC). The effect of neutron heating both in the liquid metal film as well as in the subsrate material will be by around three to four orders of magnitude lower than the laser heating limit. Hence the nuclear heating will not be a limiting factor for grazing incident liquid metal mirror (GILMM) of a laser IFE power plant. (C) 2002 Elsevier Science Ltd. All rights reserved.Öğe Protective effects of caffeic acid phenethyl ester on rotenone-induced myocardial oxidative injury(Academic Press Inc Elsevier Science, 2005) Akpinar, MB; Erdogan, H; Sahin, S; Ucar, F; Ilhan, ARotenone, an insecticide, causes toxicity through inhibition of mitochondrial electron transport chain at complex I and oxidative injury to the tissues. The aim of the present study was to determine in vivo effects of rotenone on myocardium and cardio-protective effects of caffeic acid phenethyl ester (CAPE), an antioxidant agent, against rotenone toxicity in rats. The rats were divided into three groups: untreated control, rotenone (2.5 mg/kg/day for 60 days, i.p.) and rotenone + CAPE groups. CAPE was administrated i.p. 10 ltmol/kg/day for 62 days started two days before first dose rotenone injection. The malondialdehyde, nitric oxide levels and xanthine oxidase activity of rotenone group was significantly higher than control and rotenone + CAPE groups (to < 0.05). However, catalase activity in the rotenone group was decreased in comparison with the other groups (p < 0.05). The superoxide dismutase activity of rotenone group was insignificantly decreased compared to the others. In conclusion, rotenone caused lipid peroxidation in myocardial tissue and CAPE treatment prevented this rotenone-induced lipid peroxiclation in rats. CAPE might be a cardio-protective agent against myocardial toxicities. (c) 2005 Elsevier Inc. All rights reserved.Öğe Protective effects of erdosteine on rotenone-induced oxidant injury in liver tissue(Sage Publications Inc, 2004) Terzi, A; Iraz, M; Sahin, S; Ilhan, A; Idiz, N; Fadillioglu, ERotenone, an insecticide of botanical origin, causes toxicity through inhibition of complex I of the respiratory chain in mitochondria. This study was undertaken to determine whether rotenone-induced liver oxidant injury is prevented by erdosteine, a mucolytic agent showing antioxidant properties. There were four groups of Male Wistar Albino rats: group one was untreated as control; the other groups were treated with erdosteine (50 mg/kg per day, orally), rotenone (2.5 mg/mL once and 1 mL/kg per day for 60 days, i.p.) or rotenone plus erdosteine, respectively. Rotenone treatment without erdosteine increased xanthine oxidase (XO) enzyme activity and also increased lipid peroxidation in liver tissue (P < 0.05). The rats treated with rotenone plus erdosteine produced a significant decrease in lipid peroxidation and XO activities in comparison with rotenone group (P < 0.05). Erdosteine treatment with rotenone led to an increase in catalase (CAT) and superoxide dismutase (SOD) activities in comparison with the rotenone group (P < 0.05). There was no significant difference in nitric oxide (NO) level between groups. There were negative correlations between CAT activity and malondialdehyde (MDA) level (r = -0.934, P < 0.05) with between CAT and SOD activities (r = -0.714, P < 0.05), and a positive correlation between SOD activity and MDA level (r = 0.828, P < 0.05) in rotenone group. In the rotenone plus erdosteine group, there was a negative correlation between XO activity and NO level in liver tissue (r = -0.833, P < 0.05). In the light of these findings, erdosteine may be a protective agent for rotenone-induced liver oxidative injury in rats.Öğe Protective role of ?-tocopherol and caffeic acid phenethyl ester on ischemia-reperfusion injury via nitric oxide and myeloperoxidase in rat kidneys(Elsevier, 2004) Gurel, A; Armutcu, F; Sahin, S; Sogut, S; Ozyurt, H; Gulec, M; Kutlu, NOBackground: The aim of this study was to determine the acute effects of antioxidant caffeic acid phenethyl ester (CAPE) and alpha-tocopherol (vitamin E) on nitric oxide (NO) production, neutrophil infiltration, and antioxidant enzyme activities on an in vivo model of renal ischemia-reperfusion injury. Methods: Rats were divided into five equal groups each consisting six rats: sham operation, ischemia, ischemia-reperfusion (I/R), I/R plus CAPE, and I/R plus vitamin E groups. CAPE or vitamin E was administered intraperitoneally before reperfusion. After experimental procedure, rats were sacrificed and both ipsilateral and contralateral kidneys were removed and prepared for NO concentrations, myeloperoxidase (MPO), catalase (CAT) and superoxide dismutase (SOD) activities. Results: Acute administration of vitamin E decreased NO concentrations in both ipsilateral and contralateral renal tissues compared to I/R group. SOD activity was increased in I/R and I/R + CAPE groups compared to sham operation group. The most prominent results were encountered in MPO activities, which did not change in contralateral kidneys in both ischemia and I/R groups. There was a significant decrease in ipsilateral MPO activity in ischemia group and a significant increase in I/R group compared to sham operation group. Pretreatment with intraperitoneal CAPE significantly diminished the tissue MPO activity indicating the prevention of the neutrophil sequestration into the kidney. Conclusion: There is a role for CAPE in attenuation in renal damage after I/R injury of the kidney, in part at least by inhibition of neutrophil sequestration. (C) 2003 Elsevier B.V. All rights reserved.Öğe The protective role of caffeic acid phenethyl ester (CAPE) on testicular tissue after testicular torsion and detorsion(Springer, 2002) Uz, E; Sögüt, S; Sahin, S; Var, A; Özyurt, H; Güleç, M; Akyol, ÖTesticular artery occlusion causes an enhanced formation of reactive oxygen species, which contributes to the pathophysiology of tissue damage. Here, we have investigated the effects of caffeic acid phenethyl ester (CAPE), a new antioxidant and antiinflammatory agent, in rats subjected to testicular torsion/detorsion (T/D). Thirty-five male rats were divided into four groups: sham operation group (n = 8), torsion group (n = 9), T/ D + saline group (n = 9) and T/D + CAPE group (n = 9). Rats, except the sham operation group, were subjected to left unilateral torsion (720degrees rotation in the clockwise direction) without including the epididymis. After torsion (2 h) and detorsion (4 h) periods, rats were sacrificed and bilateral orchidectomy was performed. Testis tissues were washed with cold saline solution, cut into small pieces with scissors, placed into glass bottles and homogenised in four volumes of ice-cold Tris-HCl buffer. Clear supernatant fluid was used for biochemical analyses. Treating rats with CAPE (applied at 10 mumol/kg, 30 min prior to T/D) attenuated the testicular injury, as well as the increase in the tissue levels of myeloperoxidase and thiobarbituric acid-reactant substances (TBARS) caused by T/D in the testis. Testis tissues showed a significant increase in glutathione peroxidase (GSH-Px) activity compared to the torsion group when CAPE was applied. Taken together, our results clearly demonstrate that CAPE treatment exerts a protective effect on testicular T/D, and part of this effect may be due to inhibiting the neutrophil-mediated cellular injury.Öğe Reduced shielding mass for the VISTA spacecraft(Springer Heidelberg, 2002) Sahin, S; Sahin, HM; Sahinaslan, AAn innovative concept for the direct utilization of fusion energy with laser ignited (D,T) capsules for propulsion is presented with the so called VISTA (Vehicle for Interplanetary Space Transport Applications) concept. VISTA's overall geometry is that of a 50degrees-half-angle cone to avoid massive radioactive shielding. The 50degrees-half-angle maximizes the jet efficiency, and is determined by selecting the optimum pellet firing position along the axis of the cone with respect to the plane of the magnet coil. The pellet firing position is in the vacuum. Assuming a total fusion power production of 17 500 MW with a repetition rate of 5 Hz and 3500 MJ per shot, the propulsion power in form of charged particles has been calculated as similar to7000 MW, making similar to40% of the total fusion power. About 60% of the fusion energy is carried by the leaking neutrons out of the pellet. Most of them (96%) escape into vacuum without striking the space ship. Only 4% enter the frozen hydrogen expellant in the conical shape (about 50 gr.). Two design limits are discussed, 5 and 1 mW/cm(3). Total peak nuclear heat generation in the coils is calculated as 4.7 mW/cm(3). The peak neutron heating is 1.9 mW/cm(3) and the peak gamma-ray heating density is 2.8 mW/cm(3). However, volume averaged nuclear heat generation in the coils is much lower. It is calculated as 0.18, 0.48, and 0.66 mW/cm(3) for neutron, gamma-ray, and total nuclear heating, respectively. With higher design limits for nuclear heat generation in the coils and using natural lithium in the shielding, it was possible to reduce the net shielding mass from 595 tonne down to 170 tonne, making <3% of the vehicle mass, by a total vehicle mass of VISTA similar to 6 000 tonne.Öğe The relationship between serum trace element changes and visual function in heavy smokers(Wiley, 2003) Uz, E; Sahin, S; Hepsen, IF; Var, A; Sogut, S; Akyol, OPurpose: The aim of this prospective study was to evaluate serum manganese (Mn), zinc (Zn) and copper (Cu) levels and visual functions including visual acuity, colour vision, pattern visual evoked potentials (PVEPs), and contrast sensitivity in heavy smokers and to compare these with the equivalent levels and functions in non-smokers. Methods: Data were recorded in 24 healthy, chronic and heavy cigarette smokers and 16 healthy, non-smoking control subjects. Serum Zn, Cu and Mn concentrations in all subjects were measured by atomic absorption spectrophotometry. Results: Both study and control subjects had normal visual acuity and colour vision. Pattern visual evoked potentials were normal in all study and control subjects. Contrast sensitivity was significantly reduced in heavy smokers compared to non-smokers (p<0.023), despite the fact that central vision and PVEP responses were not affected. Mean serum Mn and Zn levels were significantly lower in smokers than in non-smokers (p<0.0001 and p<0.005, respectively). Conclusions: Reduced contrast sensitivity values associated with low levels of serum Mn and Zn, which function as cofactors of superoxide dismutase in erythrocyte and other nucleated cells, suggest a possible role of trace elements in smoking-induced early retinal toxicity.Öğe Tissue xanthine oxidase activity and nitric oxide levels after spinal cord ischemia/reperfusion injury in rabbits(Wiley, 2002) Sahin, S; Sögüt, S; Özyurt, H; Uz, E; Ilhan, A; Akyol, ÖCaffeic acid phenethyl ester exhibits antioxidant properties. This experimental study was designed to determine the effect of CAPE on nitric NO level and XO activity after reperfusion injury of spinal cord. New Zealand white rabbits were undergone aortic occlusion. CAPE, methylprednisolone or saline were injected intraperitoneally before surgical intervention. Animals were subjected to 21 min of crossclamp time. At the end of occlusion time, the clamps were removed and restoration of the blood flow was verified visually. Animals in sham group underwent a surgical procedure similar to the other groups but the aorta was not occluded. Spinal cord specimens were obtained to determine the tissue levels of NO and XO activity. Both XO activity and NO level in ischemia group were significantly higher than those of sham group (p = 0.0005 and 0.0003, respectively). MP and CAPE had no effect on XO activity after reperfusion. These two agents decreased NO levels nearly to that of sham group after reperfusion. There were no differences between MP and CAPE on reducing NO level. These results suggest that rabbits with ischemia-reperfusion injury in spinal cord have increased cord concentrations of nitrite and nitrate that are indicative of endogenous overproduction of NO. CAPE may be regarded as an agent that protects spinal cord from ischemia-reperfusion injury.
