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Öğe Antibacterial activity and biochemical characteristics of hydrocele fluids(Blackwell Science Ltd, 2000) Ozbek, E; Polat, Y; Kocak, I; Turkoz, Y[Abstract Not Available]Öğe The attenuation of vasospasm by using a SOD mimetic after experimental subarachnoidal haemorrhage in rats(Springer Wien, 2003) Aladag, MA; Turkoz, Y; Sahna, E; Parlakpinar, H; Gul, MBackground. Delayed cerebral vasoconstriction and brain ischemia, are critical problems in the management of a patient affected by rupture of an intracranial aneurysm. Overexpression of Cu-Zn superoxide dismutase (Cu-Zn SOD) can reduce the extent of cerebral vasospasm. We, therefore investigated if vasospasm, can be prevented by a novel, stable, and cell permeable SOD mimetic, MnTBAP [Mn(III) tetrakis (4-benzoic acid) porphyrin] which permeates the biological membranes and scavenges superoxide anions and peroxynitrite. Methods. 28 rats (225-250 g) were divided equally into four groups: group 1: control; group 2: SAH only; group 3: SAH plus placebo; and group 4: SAH plus MnTBAP We used a double haemorrhage method to produce SAH. Starting six hours after SAH, 5 mg/kg MnTBAP (Calbiochem, Darmstadt-Germany; Cat. No 475870)) or an equal volume of 0.9% saline (37degreesC) was administered by intraperitoneal injection twice daily for 5 days to groups 4 and 3 respectively. MnTBAP or 0.9% saline injections were continued up to fifth day after SAH and rats were sacrificied on the fifth day. Brain sections at the level of the pons were examined by light microscopy. Planimetric measurements were made for the cross-sectional areas of the lumen and the vessel wall (intima plus media) of the basilar artery by a micrometer. Finding. Administration of MnTBAP significantly attenuated the vasoconstriction of the basilar artery in group 4 compared with the groups 2 and 3 (p<0.001). Interpretation. These results suggest that this SOD mimetic (MnTBAP) attenuates delayed cerebral vasoconstriction following experimental SAH and that superoxide anions have a role in the pathogenesis of vasospasm after SAH.Öğe Caffeic acid phenethyl ester (CAPE) attenuates cerebral vasospasm after experimental subarachnoidal haemorrhage by increasing brain nitric oxide levels(Pergamon-Elsevier Science Ltd, 2006) Aladag, MA; Turkoz, Y; Ozcan, C; Sahna, E; Parlakpinar, H; Akpolat, N; Cigremis, YBackground: Cerebral vasospasm, a medical complication of aneurysmal subarachnoid hemorrhage (SAH), is associated with high morbidity and mortality rates, even after the aneurysm has been secured surgically or endovascularly. Evidence accumulated during the last decade suggest that scavenging a vasodilator, nitric oxide (NO), by superoxide anions (O-2(-)), and activating a strong vasoconstructor, protein kinase C (PKC), are the two most important mechanisms in the pathogenesis of vasospasm. Our aim in this study was to determine whether caffeic acid phenethyl ester (CAPE), a non-toxic oxygen free radical scavenger, prevents vasospasm in an experimental rat model of SAH. Methods: Twenty eight rats (225-250 g) were divided into four groups equally: group 1, control group group 2, SAH group; group 3, SAH plus placebo group; and group 4, SAH plus CAPE group. We used double haemorrhage method for SAH groups. Starting 6 h after SAH, 10 mu mol/kg CAPE or an equal volume of 0.9% saline were administered by intraperitoneal injection twice daily for 5 days to SAH plus CAPE and SAH plus placebo groups, respectively. CAPE or 0.9% saline injections were continued up to 5th day after SAH. Rats were sacrificed on the 5th day. Brain sections at the level of the pons were examined by light microscopy. Measurements were made for the cross-sectional areas of the lumen and the vessel wall (intimae plus media) of basilar artery by a micrometer. The levels of malondialdehyde (MDA), reduced glutathione (GSH), and nitric oxide (NO) were measured in rat brain tissue. Results: Administration of CAPE significantly attenuated the vasoconstriction of the basilar artery. There were marked narrowing in the lumens of and thickening in the walls of basilar arteries in the SAH, and the SAH plus placebo compared with CAPE group (p < 0.001). We also observed that CAPE administration significantly decreased the tissue level of MDA, while significantly increased the tissue levels of GSH, NO in the SAH plus CAPE group compared to only SAH group, p < 0.05. Conclusions: Our results indicate that CAPE is effective in attenuating delayed cerebral vasoconstriction following experimental SAH. Our findings also suggest that the elevation of lipid peroxidation and reduction of NO bioavailability, resulting from the generation and the interaction of free radicals, have a significant role in the pathogenesis of vasospasm after SAH. (c) 2005 ISDN. Published by Elsevier Ltd. All rights reserved.Öğe Cerebrospinal fluid adrenomedullin levels in patients with pre-eclampsia(Blackwell Munksgaard, 2003) Celik, O; Hascalik, S; Yurekli, M; Turkoz, Y[Abstract Not Available]Öğe Cerebrospinal fluid nitric oxide level changes in preeclampsia(Elsevier Sci Ireland Ltd, 2003) Celik, O; Hascalik, S; Turkoz, Y; Hascalik, M; Gokdeniz, RObjective: The purpose of this study was to determine the level of nitric oxide (NO) metabolites, nitrite and nitrate in human cerebrospinal fluid (CSF) and serum and to assess whether there is any relationship among CSF, serum nitrate-nitrite levels and preeclampsia. Study design: Twenty-one preeclamptic and 27 healthy pregnant women as control group who underwent cesarean section (C/S) were included in the study. Before administering local anesthetic for spinal anesthesia, 2 ml CSF and 4 ml venous blood sample were taken. CSF and serum total nitrite, direct nitrite and nitrate levels were determined spectrophotometrically. Results: CSF total nitrite, direct nitrite and nitrate levels were significantly different between the two groups (21.00 +/- 1.68, 8.28 +/- 0.89 and 12.71 +/- 1.08 mumol/l, respectively versus 15.53 +/- 1.49, 5.57 +/- 0.39 and 9.96 +/- 1.45 mumol/l, respectively, P < 0.05). Significantly higher serum nitrate level was found (31.84 +/- 2.31 mumol/l) in the control group compared to the preeclamptic group serum nitrate level (25.06 +/- 2.02 mumol/l). Statistical comparisons were performed by the Mann-Whitney U-test. Conclusion: CSF-NO is significantly higher but serum NO is lower in preeclamptic group compared with control group may suggest independent regulation of NO in the two compartments. The determination of CSF-NO metabolites could be useful to clarify whether increased NO production is predominantly associated with poor perfusion of the brain in preeclampsia. (C) 2003 Elsevier Ireland Ltd. All rights reserved.Öğe cFN and NO levels as indexes of endothelial damage in pre-eclampsia(Elsevier Sci Ireland Ltd, 2003) Celik, O; Hascalik, S; Turkoz, Y[Abstract Not Available]Öğe Clip Turcica: a new apparatus for experimental ovarian ischemia and reperfusion model in rats(Elsevier Science Inc, 2005) Hascalik, S; Celik, O; Turkoz, Y; Mizrak, BClip Turcica is a unique, malleable, aluminum that facilitates holding and release of the adnexa during a period of experimental ovarian ischemia and reperfusion, without anesthesia and laparotomy. The simple opening and closing mechanism of the Clip Turcica allows easier, quicker, and safer application compared with previous methods. (c) 2005 by American Society for Reproductive Medicine.Öğe Comparison of the effects of Argon and Neodymium: YAG laser iridotomy on cytokines in the rabbit aqueous humor(Wichtig Editore, 2002) Er, H; Doganay, S; Evereklioglu, C; Turkoz, Y; Gündüz, A; Borazan, M; Ozyalin, FPURPOSE. We compared the effects in rabbits of iridotomy using the argon or Nd:YAG laser on cytokines such as interleukin 1-beta (IL-1beta), interleukin 6 (IL-6), interleukin 8 (IL-8), and tumor necrosis factor-alpha (TNF-alpha). METHODS. Twenty pigmented rabbits (20 eyes) underwent argon and Nd:YAG iridotomy under general and topical anesthesia. Group 1 (10 right eyes) was treated with the argon laser and group 2 (10 right eyes) with the Nd:YAG laser, using an equal number of shots and the same laser parameters for each group. Left eyes in both groups were evaluated as controls. Aqueous humor specimens were collected from each eye preoperatively and 1 and 3 days postoperatively. RESULTS. Aqueous IL-6 and TNF-a levels rose more on day 1 in the Nd:YAG group than the argon group. IL-6 and TNF-a levels were significantly higher on days 1 and 3 than the pre-operative and control levels (p<0.05). TNF-alpha levels on day 1 were significantly lower in the Nd:YAG than the argon group. There were no significant differences between the two laser groups for IL-6 on days 1 and 3. IL-1beta and IL-8 did not change CONCLUSIONS. Our findings suggest that cytokines, particularly IL-6 and TNF-alpha, may be inflammatory mediators in the early inflammation following argon and Nd:YAG laser iridotomies. These results also indicate that cytokines contribute to the acute effects of Nd:YAG and argon laser applications on inflammation.Öğe Decreased nitric oxide production in primary open-angle glaucoma(Wichtig Publ, 2002) Doganay, S; Evereklioglu, C; Turkoz, Y; Er, HPURPOSE. Raised intraocular pressure (IOP) is the major risk factor responsible for optic nerve damage in primary open-angle glaucoma (POAG). The trabecular meshwork acts as a valve in aqueous outflow and relaxes with nitric oxide (NO) agonists. Since NO is synthesized by endothelium and smooth muscle elsewhere in the body, this study investigated the NO levels in the aqueous humor of patients with POAG compared with cataract patients. MATERIALS AND METHODS. Aqueous humor samples were taken by paracentesis from 16 consecutive patients with POAG (9 male and 7 female; mean age 69.0 +/- 3.4 yrs) and 14 age and sex-matched controls with cataract (8 male and 6 female; mean age 66.7 +/- 4.1 yrs) during elective surgery. As an indicator for NO, aqueous total nitrite levels (end - product of NO) were measured by Greiss reaction. The Mann-Whitney U test was used for statistical analysis and P <0.05 was considered significant. RESULTS. The mean age and sex in two groups were comparable. The mean aqueous humor NO levels were significantly (P = 0.001) lower in patients with glaucoma (72.72 +/- 11.21 mumol/L) than in patients with cataract and no glaucoma (86.92 +/- 11.23 mumol/L). CONCLUSIONS. Decreased NO production in patients with POAG indicates that NO-producing cells may be lost as the disease progresses. The control of NO levels in the eye might be a therapeutic target in glaucoma.Öğe Effect of nitric oxide synthase inhibition in experimental Pseudomonas keratitis in rabbits(Wichtig Editore, 1998) Er, H; Turkoz, Y; Ozerol, IH; Uzmez, EPurpose. The aim of this study was to assess the efficacy of the nitric oxide synthase inhibitor L-NG-nitro-arginine-methyleser (L-NAME) in the treatment of experimental Pseudomonas keratitis. Methods. Twelve young New Zealand white rabbits were given intrastromal injections of Pseudomonas aeruginosa strains. Twenty-four hours later, the rabbits were randomly divided into four groups: group I was treated with topical 0.3% ciprofloxacin drops and a single subconjunctival injection of L-NAME (150 mg/kg); group 2 received topical 0.3% ciprofloxacin drops alone; group 3 received a single subconjunctival injection of L-NAME alone; group 4, the control group, was treated with topical balanced salt solution (BSS) drops. One drop of either ciprofloxacin of BSS was applied at each treatment interval. Twenty-six hours after the start of treatment, the eyes were examined by slit lamp to assess inflammation. Aqueous humor specimens were collected from each eye to measure the nitric oxide concentration. Corneas were removed to count bacteria results. Results. Slit lamp examination cell scores were significantly lower for groups 1 and 3 than groups 2 and 4 eyes (p = 0.002 to p = 0.004). No Viable bacteria were detected in the corneas of groups 1 and 2. Group 3 corneas had significantly fewer bacteria (6.33 +/- 0.42 x 10(3)) than group 4 (5.94 +/- 0.16 x 10(4)) (p < 0.05). Nitric oxide levels in the aqueous humor were significantly lower for group I eyes than for groups 2, 3, or 4 (p = 0.02, p = 0.01, and p = 0.003, respectively). Conclusions. We conclude that nitric oxide synthase inhibitors may be a useful adjunct but are not a replacement for traditional antibiotic drop therapy.Öğe The effect of pinealectomy and zinc deficiency on nitric oxide levels in rats with induced Toxoplasma gondii infection(E M H Swiss Medical Publishers Ltd, 2004) Baltaci, AK; Mogulkoc, R; Turkoz, Y; Bediz, CS; Ozugurlu, FPrinciples: This study aims at investigating how zinc deficiency and pinealectomy affect nitric oxide levels in rats infected by Toxoplasma gondii. Methods: The study was conducted on a total of 50 adult, male rats of Spraque-Dawley species. The study groups were as follows: General, intact control group (Group I, n = 10), infected control group (Group II, n = 10), infected and zinc-deficient group (Group III, n = 10), infected and pincalectomized group (Group IV, n = 10), infected, zinc-deficient and pinealectomized group (Group V, n = 10). After the experiment the rats were decapitated and levels of zinc, melatonin and total nitrite were identified in the blood samples collected. Results: The total nitrite levels in groups TV and V were more than those in all other groups (p <0.01). The total nitrite levels in Group II were also higher than those in Groups I and III (p <0.01). Plasma zinc levels in the zinc-deficient group and zinc-deficient and pinealectomized group were lower than those in all other groups, while melatonin levels were lower in Infected pinealectomized group (Group IV) and infected, zinc-deficient and pinealectomized group (Group V) than all others (p <0.01). Conclusions: The present study shows that plasma nitric oxide levels increase during Toxoplasma gondii infection, but this increase becomes more apparent in the presence of melatonin deficiency and is inhibited by zinc deficiency.Öğe Effect of resveratrol in experimental osteoarthritis in rabbits(Springer Basel Ag, 2005) Elmali, N; Esenkaya, I; Harma, A; Ertem, K; Turkoz, Y; Mizrak, BObjective: Resveratrol (trans-3,4',5-trihydroxystilbene) is a phytoalexin found in high concentration in the skins of grapes and red wines which has been shown to have antiinflammatory, anticancerogen and antioxidant properties. Resveratrol is a potent and specific inhibitor of nuclear factor kappa B ( NF-kappa B). Resveratrol also inhibits COX-2 gene expression and enzyme activity. We aimed to determine the in vivo effects of intra-articular injections of resveratrol on cartilage and synovium in an experimental osteoarthritis (OA) model in rabbits. Methods: As OA model, rabbits underwent unilateral anterior cruciate ligament transection (ACLT). Five weeks after test group was injected with 10 mu Mol/kg resveratrol in dimethylsulphoxide ( DMSO) in the knees once daily for two weeks and as the control group at the same time DMSO was injected into the knees. All rabbits were killed one week after the last injection. Cartilage tissue and synovium were evaluated with a histological scoring system. Results: Histological evaluation of cartilage tissue by H&E staining revealed a significantly reduced average cartilage tissue destruction score of 1.7 in the resveratrol group versus 2.8 in the control group ( p = 0.016). Loss of matrix proteoglycan content in cartilage was also much lower, as determined by safranin O staining. Scores of synovial inflammation didn't show difference between groups ( 1,3 vs 2,2; p = 0.057). Conclusion: A characteristic parameter in arthritis is the progressive loss of articular cartilage. This study suggests that intraarticular injections of resveratrol starting at the onset of disease may protect cartilage against the development of experimentally induced OA.Öğe Effects of aminoguanidine against renal ischaemia-reperfusion injury in rats(Wiley, 2006) Sahna, E; Parlakpinar, H; Cihan, OF; Turkoz, Y; Acet, AAminoguanidine is an inhibitor of nitric oxide synthase (NOS), with high selectivity for the inducible isoforrn (iNOS). In addition to being all inhibitor of NOS, aminoguanidine also exhibits antioxidant activity. Recent studies suggest that aminoguanidine reduces ischaemia-reperfusion (I/R)-induced damage. However, the role of aminoguanidine, in renal injury associated with I/R remains unknown. This Study was designed to investigate the effects of aminoguanidine on renal I/R injury. There were three groups of eight rats each. I/R was induced by occlusion of the left renal vessels for 60 min, followed by 24 h reperfusion in rats. Malondialdehyde (MDA) levels, a stable metabolite of the free radical-mediated lipid peroxidation cascade, were found to be significantly higher in the I/R group (30.3 +/- 0.1 nmol g(-1) tissue) than in the control group (10 +/- 0.05 nmol g(-1)). Aminoguanidine (100 mg kg(-1)) administration to rats significantly reduced the MDA values. We also demonstrated that I/R leads to structural change but aminoguanidine did not reverse this change. Aminoguanidine, according to the biochemical finding is protective but histopathological findings did not reveal protection against I/R injury in kidney. The effects of aminoguanidine on I/R-induced damage remain a subject for future investigations. Copyright (c) 2004 John Wiley & Soils, Ltd.Öğe Effects of aminoguanidine and antioxidant erdosteine on bleomycin-induced lung fibrosis in rats(Academic Press Inc Elsevier Science, 2004) Yildirim, Z; Turkoz, Y; Kotuk, M; Armutcu, F; Gurel, A; Iraz, M; Ozen, SReactive oxygen and nitrogen species have been implicated in the pathogenesis of bleomycin -induced lung fibrosis. The effects of aminoguanidine and erdosteine on the bleomycin-induced lung fibrosis were evaluated in rats. The animals were placed into five groups: Vehicle + vehicle, vehicle + bleomycin (2.5U/kg), bleomycin + aminoguanidine (200mg/kg), bleomycin + erdosteine (10mg/kg), and bleomycin + erdosteine + aminoguanidine. Bleomycin administration resulted in prominent lung fibrosis as measured by lung hydroxyproline content and lung histology, which is completely prevented by erdosteine and aminoguanidine. A strong staining for nitro tyrosine antibody in lung tissue and increased levels of lung NO were found in bleomycin group, that were significantly reduced by aminoguanidine and erdosteine. Aminoguanidine and erdosteine significantly prevented depletion of superoxide dismutase and glutathione peroxidase and elevated myeloperoxidase activities, malondialdehyde level in lung tissue produced by bleomycin. Data presented here indicate that aminoguanidine and erdosteine prevented bleomycin-induced lung fibrosis and that nitric oxide mediated tyrosine nitration of proteins plays a significant role in the pathogenesis of bleomycin-induced lung fibrosis. Also our data suggest that antifibrotic affect of antioxidants may be due to their inhibitory effect on nitric oxide generation in this model. (C) 2004 Elsevier Inc. All rights reserved.Öğe The effects of chronic exposure to ethanol and cigarette smoke on the level of reduced glutathione and malondialdehyde in rat kidney(Springer, 2004) Cigremis, Y; Turkoz, Y; Akgoz, M; Sozmen, MThe aim of this study was to investigate the effects of chronic ethanol intake and cigarette smoke exposure on rat kidney. The animals were divided into four experimental groups: (1) the control group (C), (2) the ethanol group (E), (3) the cigarette smoke group (CS), and (4) the cigarette smoke plus ethanol group (CS+E). Apart from the control group, these were treated with ethanol and/or cigarette smoke for 6 months. The animals were killed and the kidneys removed to determine the levels of reduced glutathione (GSH) and malondialdehyde (MDA) and for histopathological analysis. The levels of GSH/g wet tissue were 1.58+/-0.09 mumol, 0.91+/-0.05 mumol, 1.14+/-0.06 mumol, and 0.82+/-0.04 mumol for C, E, CS, and CS+E, respectively. In groups of E, CS, and CS+E, the GSH values were significantly lower than that of group C animals (P<0.05). Although, we detected lower GSH levels in the CS+E than the CS group (P<0.05), a significant difference in GSH levels between CS+E and E was not observed. The levels of MDA/g wet tissue were 40.1+/-3.4 nmol, 71.4+/-2.8 nmol, 64.0+/-3.6 nmol, and 76.5+/-4.3 nmol, for C, E, CS and CS+E, respectively. In E, CS, and CS+E, the MDA values were significantly higher than in group C (P<0.05). The increase in MDA levels in CS+E were not significantly different from groups E or CS. Histopathological analysis of the kidney slices showed severe degeneration of the tissues. Advanced hydropic degeneration of kidney tubules was clearly observed in the CS group. In group E, advanced tubular and interstitial damage, mononuclear cell infiltration and tubular thyroidization were clearly visible. In group CS+E, an intense inflammatory cell infiltration was detected under the transitional epithelium. We conclude that chronic exposure to ethanol and cigarette smoke may cause an oxidative burst in rat kidney by increasing the formation of reactive oxygen species.Öğe Effects of misoprostol on lipoprotein (a) levels of ovariectomized rats(Elsevier Science Inc, 1999) Sonmez, AS; Birincioglu, M; Turkoz, Y; Adam, B; Lurie, D; Chuong, CJObjective: To determine the effects of misoprostol on plasma lipoprotein (a) concentrations of ovariectomized rats. Design: Controlled prospective study. Setting: Animal research laboratory. Animal(s): Four-month-old female Sprague-Dawley rats. Intervention(s): Blood samples were obtained before and 60 days after ovariectomy, and the rats were divided into three groups. Group I (five rats) was treated with vehicle (water); groups II and III (nine and eight rats, respectively) were treated with oral misoprostol at 100 and 200 mu g/kg/d, respectively, for 60 days, after which blood was drawn again. Main Outcome Measure(s): Serum lipoprotein (a) levels. Result(s): The median lipoprotein (a) level before ovariectomy was 10.8 mg/dL (range, 10.6-46.5 mg/dL). Sixty days after ovariectomy, the level increased significantly to 15.9 mg/dL (range, 10.6-36.9 mg/dL). After treatment, there was no change in lipoprotein (a) levels in the vehicle-treated group (range, 16.3-21.1 mg/dL); however, the lipoprotein (a) levels decreased significantly in the group treated with 100 mu g/kg/d of misoprostol, from 15.4 mg/dL to 10.8 mg/dL, and in the group treated with 200 mu g/kg/d of misoprostol, from 17.1 mg/dL to 10.6 mg/dL. Conclusion(s): Misoprostol caused a significant decrease in lipoprotein (a) levels. (Fertil Steril(R) 1999;72: 518-21. (C) 1999 by American Society for Reproductive Medicine.) 518.Öğe Effects of NG-nitro L-arginine and corticosteroids on aqueous humor levels of nitric oxide and cytokines after cataract surgery(Elsevier Science Inc, 1999) Er, H; Gündüz, A; Turkoz, Y; Çigli, A; Isci, NPurpose: To assess the efficacy of nitric oxide synthesis (NOS) inhibitor, topical steroids, and nonsteroidal anti-inflammatory drugs on aqueous levels of nitric oxide (NO) and cytokines after cataract surgery. Setting: Research Laboratory, Inonu University Turgut Ozal Medical Center, Malatya, Turkey. Methods: Fifteen rabbits had intercapsular phacoemulsification and were randomly divided into 3 treatment groups: Group 1 was treated with topical prednisolone acetate 1% drops 5 times a day for 1 week; Group 2, flurbiprofen 0.03% drops 5 times a day for 1 week; Group 3, a 0.1 cc subconjunctival injection of NG-nitro L-arginine (L-NAME) (150 mg/kg) 1 day and 3 days after surgery. Three rabbits serving as controls received a subconjunctival injection of an equal volume of balanced salt solution (BSS(R)) at the same times as the L-NAME injections. Aqueous humor specimens were collected from each eye to determine NO and cytokine levels including interleukin-1-beta (IL-1 beta), interleukin-2R (IL-2R), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha), Results: The levels of IL-1 beta and IL-6 were higher in Group 2 and the control group than in Groups 1 and 3 at ail times. The differences were not statistically significant (P <.05), Nitric oxide and TNF-alpha levels in Groups 1 and 3 were significantly lower than in Groups 2 and the controls 1, 3, and 7 days postoperatively (P <.05). Conclusion: These findings suggest a strong inhibitory effect of NOS inhibitors and corticosteroids on aqueous levels of TNF-alpha and NO and no inhibitory effect on IL-1 beta and IL-6 levels after cataract surgery. J Cataract Refract Surg 1999; 25:794-799 (C) 1999 ASCRS and ESCRS.Öğe Effects of pinealectomy and exogenous melatonin on rat hearts(Elsevier Gmbh, 2004) Muzrak, B; Parlakpinar, H; Acet, A; Turkoz, YThe effects of pinealectomy and administration of melatonin, the major secretory product of the pineal gland, which is a direct free radical scavenger and an indirect antioxidant, were studied in rat hearts on the basis of cardiac morphology and biochemical findings. Three groups of Wistar rats were used: one group was the shamoperated control, one group consisted of pinealectomized rats and one group consisted of pinealectomized rats that were treated with melatonin. Serum cholesterol, tissue levels of malondialdehyde (MDA) and reduced glutathione (GSH), and heart weight were determined. Histochemical staining with the Van Gieson, PAS/ Alcian blue at pH 2.5 and Masson's trichrome methods were performed in addition to hematoxylin-eosin staining. Levels of serum cholesterol and tissue MDA, and heart weight were increased in pinealectomized rats whereas GSH levels did not change. Melatonin administration reversed these effects. Microscopically, myocardial fibrosis and myxomatous degeneration of cardiac valves were detected in all pinealectomized rats. It can be concluded that pineatectomy of rats causes morphological changes in rat hearts, and short-term application of metatonin does not reverse these changes. (C) 2003 Elsevier GmbH. All rights reserved.Öğe Hypochlorous acid for accidental vincristine overdose: A preliminary experimental study(Inst Exp Pathol Oncol Radiobiol, 2003) Ozgen, U; Stout, M; Turkoz, Y; Ozugurlu, F; Kutlu, NO; Soylu, H; Koltuksuz, UAim: to investigate the potential efficacy of in vivo treatment of accidental vincristine (VCR) overdose using hypochlorous acid (HOCl). Methods: 24 New Zealand rabbits were divided into 4 groups as control, HOCl-treated, VCR + treated and HOCl + VCR-treated, and their clinical and laboratory indexes were examined. Results: there were no clinical and laboratory abnormalities observed in control and HOCl group subjects. All rabbits died after quadriplegia and respiratory insufficiency in VCR and HOCl + VCR groups. Bone marrow suppression was more pronounced and onset of the neurotoxicity was early in VCR group compared to HOCl + VCR group subjects. Serum half-life of VCR was lower in HOCl + VCR group animals suggesting a contribution of HOCl in eliminating VCR resulting in the observed clinical and laboratory differences in these two groups. Conclusion: although further research is necessary, our results indicate a potential role for HOCl in the treatment of accidental VCR overdose.Öğe Increased nitric oxide production in patients with Behcet's disease: Is it a new activity marker?(Mosby, Inc, 2002) Evereklioglu, C; Turkoz, Y; Er, H; Inaloz, HS; Ozbek, E; Cekmen, MBackground. The origin of Behcet's disease (BD) is unclear. One of the prominent features of BD is vasculitis and thrombosis as a result of endothelial dysfunction. Because nitric oxide (NO) is synthesized by endothelium, we considered it as an interesting target of investigation in BD. Objective: Our purpose was to define the level of NO in the serum of patients with BD and its relation with disease activity. Methods: As an indicator for NO, serum total nitrite levels (end product of NO) were measured by Griess reaction in 52 consecutive patients with BD and compared with 32 age- and sex-matched healthy staff volunteers. Serum NO levels of active and inactive patients were compared. Results: The overall serum nitrite levels in patients with BD (40.25 +/- 10.51 mumol/L) were significantly higher (P < .001) than those in healthy volunteers (25.09 +/- 5.33 mumol/L). The difference in serum total nitrite levels among patients with active BD (46.74 +/- 10.62 mumol/L) and inactive BD (33.24 +/- 3.73 mumol/L) was significant (P < .001). Significant differences were observed in serum nitrite between patients in the inactive period of BD and the control group (P < .001). Conclusion: Increased NO production might be responsible for the inflammatory process of BD, NO seems to be related to disease activity.
