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Öğe The antioxidant effects of taurine, melatonin and N-acetylcysteine in cadmium-induced lung injury(Ekin Tibbi Yayincilik Ltd Sti-Ekin Medical Publ, 2007) Aydogdu, Nurettin; Erbas, Hakan; Kaymak, KadirObjectives: The potential protective and therapeutic effects of taurine, melatonin and N-acetylcysteine (NAC), which are recognized as antioxidant agents, in cadmium chloride (CdCl2)-induced lung injury were compared. Study Design: Ninety male Sprague-Dawley rats were divided into 9 groups. During the 3 months treatment period, group 1 received drinking water, group 2 200 ppm CdCl2, group 3 200 ppm CdCl2 and 1 % taurine, to, group 4, 200 ppm CdC12 and 0.02% melatonin, and group 5 received 200 ppm CdCl2 and 0.5% NAC all added into drinking water in each group. After, groups 6, 7, 8 and 9 received 200 ppm CdC12 in their drinking water for 3 months, group 6 was given drinking water, group 7, 4% taurine, group 8, 0.08% melatonin and group 9, 2% NAC, each for 7 days. Results: Melatonin and NAC which were given for protective purposes, increased the decreased glutathione levels. The 3 substances that were administered for both protective and therapeutic purposes, decreased the increased malondialclehyde levels, one of the end products of lipid peroxiclation. Conclusion: Taurine, melatonin and NAC play protective and therapeutic roles in CdC12 induced lung injury.Öğe Asymmetric dimethylarginine in experimental breast cancer; action of Vitamin C and E(Pakistan Medical Assoc, 2015) Erbas, Hakan; Turksever, Aylin; Aydogdu, Nurettin; Cakir, ErolObjective: To investigate the arginase-nitric oxide synthase paradox through asymmetric dimethylarginine, symmetric dimethylarginine and nitric oxide levels, and to see the effect of antioxidant vitamins on this mechanism of cancer action. Methods: The animal-based study was conducted at Trakya University, Turkey, in 2008, and comprised mice that were divided into five equal groups. Group 1 had healthy controls, while in the other four groups breast cancer was induced. Group 2 received saline solution, group 3 received 200 mg/kg/day vitamin C (tumour +vit C), group 4 received 300 mg/kg/day vitamin E (tumour +vitE) and group 5 received both 200 mg/kg/day vitamin C and 300 mg/kg/day vitamin E (tumour +vit C+vit E) for 15 days intra-peritoneally. Arginine, asymmetric dimethylarginine, symmetric dimethylarginine and nitric oxide levels were determined in each group. Results: The 50 mice in the study were divided into five groups of 10(20%) each. Plasma arginine levels were significantly decreased, asymmetric dimethylarginine and symmetric dimethylarginine levels were increased, while plasma nitric oxide level was significantly decreased in group 2. There was no statistically significant difference in treatment groups for all parameters (p>0.05 each). Conclusion: Understanding of the mechanism may help to develop new anti-cancer agents.Öğe Breast cyst fluid plasmin activity and its effect on TGF-?2 activation(Taylor & Francis Inc, 2008) Erbas, Hakan; Erten, Oya; Irfanoglu, Mehmet E.There are two types of breast cyst and women with apocrine breast cyst may have a higher risk of developing breast cancer than cyst lined by flattened epithelium. Transforming growth factor-beta's growth inhibitory effect on epithelial cells suggests a potential protective role in breast cancer. The aim of this study was to investigate the presence of plasmin in both breast cyst groups and the possible role of plasmin on transforming growth factor beta activation. Presence of high plasmin level may indicate its importance on activation process, but some other proteases may also involve in this activation mechanism.Öğe Cognitive dysfunction in patients with chronic obstructive pulmonary disease(Yerkure Tanitim & Yayincilik Hizmetleri A S, 2018) Pekel, Nilufer Buyukkoyuncu; Turgut, Nilda; Altiay, Gundeniz; Demir, Muzaffer; Turgut, Burhan; Erbas, Hakan; Sut, NecdetObjective: Chronic obstructive pulmonary disease (COPD) is characterized with air flow limitation. Cognitive problems can appear in advanced stage of COPD. There is relationship between COPD and levels of homocystein (hcy) and total antioxidant capacity (TAC). There is also relationship between cognitive dysfunction and levels of hcy and TAC. We aimed evaluation of cognitive functions in patients with COPD, and demonstration of the relationship between cognitive function and hcy and TAC. Methods: Twenty-eight hypoxic (group 1), 28 non-hypoxic COPD patients (group 2) and 25 healthy people (control group, group 3) were included to study. Hcy and TAC levels were measured in all subjects. Cognitive functions were evaluated in all subjects with standardized mini mental test (SMMT), clock drawing test (CDT), Blessed orientation memory concentration test (BOMCT), Benton's facial recognition test (BFRT) and clinical dementia rating scale (CDRS). Results: Hcy levels were high in group 1 (p=0.004), TAC levels were high in group 1 and 2 (p=0.04). SMMT (p=0.000) and CDT values were low in group1 (p=0.000), CDRS values were high in group1 and 2 (p=0.000), BFRT values were low in group1 and 2 (p=0.000), BOMCT values were high in group1 (p=0.000). There were a correlation between TAC and SMMT (r=0.582, p=0.001) and CDRS (r=-0.384, p=0.044). Conclusions: We demonstrated presence of cognitive dysfunction in COPD patients. Patients with hypoxic had more profound cognitive dysfunction. In addition, we demonstrated a relationship between TAC and cognitive dysfunction.Öğe The effects of dietary ascorbic acid supplementation on collagen and amino acid concentrations in Japanese quails exposed to heat stress(Tubitak Scientific & Technological Research Council Turkey, 2010) Seyrek, Kamil; Erbas, Hakan; Serter, Mukadder; Yenisey, Cigdem; Kiral, Funda; Bardakcioglu, Huesnue ErbayA considerable body of data exists regarding the role of vitamin C in mammalian physiology; however, there are no data about the effects of dietary ascorbic acid supplementation on collagen concentrations and amino acid levels in animals exposed to heat stress. The present study investigated the effects of supplementary ascorbic acid intake on collagen concentrations in the brain and heart tissue in Japanese quails. In addition, glycine, glutamine, histidine, asparagine, and serine contents in the livers of the same animals were measured. Japanese quails were allocated into 4 groups, each of which was exposed to heat stress (34.8 +/- 1.25 degrees C) for 75 days. Control animals were fed a basal diet, while animals in the experimental groups were fed a basal diet supplemented with 150, 250, or 500 mg of L-ascorbic acid kg(-1) of diet. Compared to the control group, mean collagen concentration in brain tissue significantly (P < 0.05) increased only in Japanese quails given 250 mg of L-ascorbic kg(-1) of diet. On the other hand, heart tissue collagen content in the quails fed vitamin C did not significantly increase; in fact, the collagen content in the group fed 500 mg of L-ascorbic acid kg(-1) of diet significantly decreased (P < 0.01). Amino acid content in the liver significantly increased in the group fed 150 mg of L-ascorbic acid kg(-1) of diet (P < 0.01 for serine and P < 0.001 for the others). In conclusion, vitamin C had profound effects on collagen synthesis and amino acid metabolism in Japanese quails subjected to heat stress. Results of the present study also indicate that addition of high-dose dietary vitamin C-higher than 250 mg kg(-1) of diet-may have detrimental effects in quails exposed to heat stress.Öğe The effects of taurine, melatonin and acetylcysteine on nitric oxide, lipid peroxidation and some antioxidants in cadmium induced liver injury(Erciyes Univ Sch Medicine, 2007) Aydogdu, Nurettin; Kanter, Mehmet; Erbas, Hakan; Kaymak, KadirPurpose: Our aim was to investigate both the potential protective and therapeutic effects of taurine, melatonin and acetylcysteine in cadmium induced liver injury. Material and Methods: Ninety male Spraque Dawley rats were divided into nine groups. For the three months treatment period, drinking water was administered to Group 1 whereas 200 ppm CdCl2 to Group 2, 200 ppm CdCl2 and 1% taurine to Group 3, 200 ppm CdCl2 and 0.02% melatonin to Group 4 and 200 ppm CdCl2 and 0.5%acetylcysteine to Group 5. Groups 6, 7, 8 and 9 received 200 ppm CdCl2 in their drinking water for 3 months. After this period, for 7 days, 4% taurine to group 7, 0.08% melatonin to Group 8 and 2% acetylcysteine to group 9 were applied. Results: In liver tissues of cadmium received rats, the levels of glutathione (GSH) and the enzyme activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) were decreased. Thiobarbituric acid reactive substances (TBARS), nitric oxide (NO) and inducible nitric oxide synthase (iNOS) activities were increased. While, taurine, melatonin and acetylcysteine increased GSH levels, SOD and GPx activities, it decreased TBARS, NO and iNOS activities. Conclusion: Taurine, melatonin and acetylcysteine may have both protective and therapeutic effects in cadmium induced liver injuries.Öğe The Effects of Taurine, Melatonin and N-Acetylcystein on Cadmium Exposure Bone Changes The Surprising Effect of Taurine(Gazi Univ, Fac Med, 2020) Tastekin, Nurettin; Aydogdu, Nurettin; Altun, Gulay Durmus; Erbas, Hakan; Uzunca, Kaan; Birtane, Murat; Kaplan, MustafaBackground: Chronic environmental and occupational exposure to cadmium can result in skeletal system changes. The main objective of the present study was to investigate and compare the effects of taurine, melatonin and N-acetyl cysteine on cadmium exposure induced bone density loss. Methods: 90 adult male Sprague-Dawley rats were allocated into four main groups: Group I was the control group; Group II was the cadmium exposure group; Group 3 was cadmium exposure for 3 months + concurrent antioxidant administration group. The concept of Group 4 was cadmium exposure for 3 months + subsequent antioxidant administration. Bone mineral density values were evaluated in all the groups. Serum calcium, phosphorus, alkaline phosphatase (ALP) enzyme activities and 24 hours urine calcium excretion levels were measured. Kruskal-Wallis test was used to compare the all groups. Between two group comparisons, the Mann-Whitney U test was used. Results: There was no significant difference in terms of bone mineral density values only between control group and cadmium exposure group (p 0.05). Mean bone mineral density values obtained in cadmium + concurrent taurine and cadmium + subsequent taurine groups were significantly lower than all the other groups (p<0.05). 24 hours urine calcium excretion levels were significantly higher in groups which taurine and n-asetylcystein were administered after cadmium exposure. Conclusion: Taurine, which is thought to have protective effects as an antioxidant caused a marked bone damage after exposure to cadmium. Further studies are needed to clarify this effect of taurine.Öğe Effects of Vitamin A and E on arginase activity, ornithine and urea levels in brain tissues of rats on long-term alcohol administration(Aves Yayincilik, Ibrahim Kara, 2007) Kundak, Ayse A.; Erbas, Hakan; Guelen, Sendogan; Doekmeci, Guelbin; Celik, Hueseyin; Oezcan, TurgutObjectives: The effect of long-term alcohol administration on brain arginase enzyme activity, ornithine and urea levels and the changes induced by administration of vitamins C and E were investigated. Study Design: I Seventy-five, male Wistar Albino rats between 4-6 months of age were used. Five study groups, each consisting of 15 rats were formed. The first group received oral glucose with a calorie value equivalent to alcohol. The second group received alcohol, the third, fourth and fifth groups received vitamins C, E and C+E, respectively, in addition to alcohol, for 20 weeks. All animals were sacrificed by the end of 20 weeks and arginase activity, ornithine and urea levels were measured in brain tissue samples. Results: In the treatment groups, arginase activities, ornithine and urea levels were significantly higher than the alcohol group (group 2). Conclusion: These results suggest that the nitric oxide synthase (NOS) enzyme which. isshown to. have increased in chronic alcohol intake, may cause a decrease in arginase enzyme activity via depleting the L-arginine pool. Antioxiclant replacement therapy may increase the arginase enzyme activity and therefore lead to a decrease in nitric oxide production which has been shown to have some negative effects. On the other hand, simultaneously increased polyamine production may potentiate the beneficial effects of these vitamins. Thus, vitamins C and E may prove to be effective in reducing the deleterious effects of chronic alcohol consumption.Öğe Evaluation of Glucose Metabolism and Cardiovascular Risk Factors in Prepubertal Girls with Premature Pubarche(Galenos Publ House, 2022) Bezen, Digdem; Kokenli, Filiz Tutunculer; Dilek, Emine; Seleci, Didem Ag; Erbas, HakanObjective: Premature pubarche (PP) is a risk factor for metabolic syndrome (MS). The aim was to evaluate if glucose-insulin metabolism, cardiovascular risk factors, familial cardiovascular risk factors (FCVRF) created a risk for insulin resistance (IR) and if PP was a risk factor alone for MS in normal weight prepubertal girls with PP. Methods: Thirty-five prepubertal, non-obese girls with PP with normal birth weight and 35 age-matched control girls were evaluated for FCVRF, anthropometric measurements, blood pressure, lipid profile, fasting blood glucose-insulin, hemoglobin A1c (HbA1c), sex hormone binding globulin (SHBG), leptin, adiponectin, tumor necrosis factor-alpha (TNF-alpha), androgen levels, and bone age. Oral glucose tolerance test was performed in PP participants. Homeostasis model of assessment of IR (HOMA-IR), fasting glucose/insulin ratio, atherogenic index (AI), and free androgen index (FAI) were calculated. PP participants were further stratified by FCVRF. Results: HbA1c, lipid profile, testosterone, leptin, adiponectin, TNF-alpha, HOMA-IR, glucose/insulin ratio, AI, and fasting glucose-insulin levels were similar. In the PP group FAI was significantly higher (p=0.001), whereas SHBG was significantly lower (p=0.010) than the control group. Leptin levels of FCVRF+ and FCVRF-subgroups were 15.2 +/- 9.1 and 9.7 +/- 7.2 ng/mL, respectively and the difference was significant (p=0.016). Conclusion: As PP does not appear to be a risk factor alone for impaired glucose metabolism and IR in prepubertal non-obese girls with normal birth weight, it is our opinion that it is unnecessary to examine in detail such cases before puberty. Low SHBG levels in the PP group and high leptin levels in FCVRF+ subgroup might suggest that these may be predictive for MS in the future.Öğe Investigation of the Effects of Tetrahydrobiopterin and L-arginine on the Renal Function and Damage in the Physiopathology of the Experimental Myoglobinuric Acute Kidney Injury(Wiley, 2017) Aydogdu, Nurettin; Erbas, Hakan; Tastekin, Ebru; Kaya, Oktay; Sut, Necdet[Abstract Not Available]Öğe Melatonin reduces nitric oxide via increasing arginase in rhabdomyolysis-induced acute renal failure in rats(Taylor & Francis Ltd, 2006) Aydogdu, Nurettin; Erbas, Hakan; Atmaca, Gulizar; Erten, Oya; Kaymak, KadirMelatonin, the chief secretory product of the pineal gland, is a direct free radical scavenger. In addition to a direct scavenging effect on nitric oxide (NO), its inhibitory effect on nitric oxide synthase (NOS) activity has been also reported. L-arginine is the substrate for both NOS and arginase. It has been suggested that there is a competition between arginase and NOS and that they control each other's level. NO plays a crucial role in the pathogenesis of myoglobinuric acute renal failure (ARF). In this study, the authors aimed to investigate the effect of melatonin on arginase activity, ornithine, and NO levels on the myoglobinuric ARF formed by intramuscular (im) injection of hypertonic glycerol. Forty rats were randomly divided into four groups. Rats in SHAM were given saline, and those in groups ARF, ARF-M5, and ARF-M10 were injected with glycerol (10 mL/kg) im. Concomitant and 24 hours after glycerol injection for the ARF-M5 and ARF-M10 groups, melatonin-5 mg/kg and 10 mg/kg, respectively-was administrated intraperitoneally. Forty-eight hours after the glycerol injection, kidneys of the rats were taken under anesthesia. Arginase activity, ornithine, and NO levels in the kidney tissue were determined. Melatonin had an increasing effect on kidney tissue arginase activities and ornithine levels while decreasing NO concentration. It is possible that besides the direct scavenging effect, the stimulatory effect of melatonin on arginase activity may result in an inhibition of NOS activity and, finally, a decrease in the kidney NO level.Öğe The Protective Effect of Curcumin on Ionizing Radiation-induced Cataractogenesis in Rats(Galenos Publ House, 2012) Ozgen, Seher Cimen; Dokmeci, Dikmen; Akpolat, Meryem; Karadag, Cetin Hakan; Gunduz, Ozgur; Erbas, Hakan; Benian, OmerObjective: The aim of the study was to determine the protective effect of curcumin against ionizing radiation-induced cataract in the lens of rats. Material and Methods: Rats were divided into six groups. Group 1: Control, Group 2: Dimethyl sulfoxide (DMSO), Group 3: DMSO+curcumin, Group 4: Irradiation, Group 5: Irradiation+DMSO, Group 6: Irradiation+DMSO+curcumin. A 15 Gy total dose was given to 4, 5, 6 groups for radiation damage. Curcumin (100 mg/kg) was dissolved in DMSO and given by intragastric intubation for 28 days. At the end of the experiment, lenses were graded and enucleated. The lenticular activity of the antioxidant enzymes, total antioxidant and glutathione peroxidase (GSH-Px), and the malondialdehyde (MDA) were measured. Results: 100% Cataract was seen in the irradiation group. Cataract rate fell to 40% and was limited at grade 1 and 2 in the curcumin group. In the irradiation group, antioxidant enzyme levels were decreased, MDA levels were increased. There was an increase in antioxidant enzyme levels and a significant decrease in MDA in the group which was given curcumin. Conclusion: Curcumin has antioxidant and radioprotective properties and is likely to be a valuable agent for protection against ionizing radiation. Hence, it may be used as an antioxidant and radioprotector against radiation-induced cataractogenesis.Öğe Protective role of carnitine in breast cancer via decreasing arginase activity and increasing nitric oxide(Wiley, 2007) Erbas, Hakan; Aydogdu, Nurettin; Usta, Ufuk; Erten, OyaBreast cancer remains one of the most common types of cancer. High levels of arginase and ornithine in different carcinomas may indicate their relation to cancer. Carnitine is a cofactor required for the transformation of free long-chain fatty acids into acetyl-carnitines. We have examined the protective effect of carnitine and the possibility that it disturbs arginase-nitric oxide (NO) interaction. Histopathological examination, arginase activity, ornithine and NO levels were determined in tumour tissues. Mitotic cells significantly decreased in the treatment group. Tissue arginase activity and ornithine levels decreased significantly with carnitine. NO levels were significantly higher in the treatment group. One of the possible mechanisms of carnitine's protective role in tumour progression might be its promotion of NO. This mechanism could decrease the production of tumour-promoting agents, polyamines, and increase the production of NO, thereby exerting a protective effect on cancer development. (c) 2007 International Federation for Cell Biology. Published by Elsevier Ltd. All rights reserved.Öğe The Reasons of Elevated Serum Transaminases in Childhood(Turkish Biochem Soc, 2008) Celtik, Coskun; Erbas, Hakan; Kursun, Oemer Serhat; Bostancioglu, Musa; Inan, Mustafa; Oner, Naci; Acunas, Betuel AysePurpose: To determine the reasons of high serum serum transaminases levels and show the differences according to age and aetiology. Method: During the three years period, 250 cases with elevated serum transaminase levels among the children who hospitalized with various reasons were included to this study. The aetiological factors which caused high serum transaminase levels were classified according to the age groups (newborn, infants and older children). The mean serum transaminase levels were also determined according to aetiological factors. Results: In newborn period, most of the hipertransaminasemia causes were idiopathic. The most frequent pathological causes were perinatal asphyxia, haemolytic diseases and non-hepatitis infections, respectively. The most frequent causes of hipertransaminasemia were drug usage and non-hepatic infections in infancy period, while infectious hepatitis and drug usage were in older children. Among all of the groups, maximum transaminase levels were observed in the patients with infectious hepatitis. Interestingly, in some cases with abdominal blunt trauma, hypertransaminasemia were determined without hepatic injury. Conclusion: The ages and enzyme levels are important for the differential diagnosis of hipertransaminasemia and it should be taken into consideration that high serum transaminase levels could be obtained, even direct hepatic damage had not been observed.Öğe Tissue damage in rat ovaries subjected to torsion and detorsion(Springer, 2008) Usta, Ufuk; Inan, Mustafa; Erbas, Hakan; Aydogdu, Nurettin; Puyan, Fulya Oz; Altaner, SemsiWe aimed to evaluate histopathological changes, to detect HIF-1 alpha staining intensities and to determine MDA levels in rat ovaries, which were subjected to torsion and detorsion and treated with L-carnitine or N-acetyl cysteine (NAC). Forty-eight prepubertal female Sprague-Dawley rats were divided into five groups (n = 8): 1, control; 2, ischemia; 3, reperfusion; 4, L-carnitine; and 5, NAC groups. In groups 3, 4 and 5, an ischemic period of 3 h was followed by reperfusion for 24 h. In groups 4 and 5, ischemia was performed and either L-carnitine or NAC was infused intraperitoneally 30 min before reperfusion. Ovarian tissues were examined histopathologically; tissue MDA levels and serum IL-6 levels were determined biochemically. HIF-1 alpha was applied to all ovaries immunohistochemically. Total tissue damage scores, tissue MDA levels and HIF-1 alpha scores, were significantly higher in group 2 (all P < 0.001) than group 4, and group 3 than group 4 (P < 0.001, P = 0.05 and P < 0.001, respectively). They were also significantly higher in group 2 (all P < 0.001) than group 5. When group 3 is compared to group 5, total tissue damage scores and tissue MDA levels were significantly higher in the former (P < 0.01 and P < 0.001, respectively). Serum IL-6 levels were significantly higher in group 2 when compared to groups 1, 4 and 5 (all P < 0.01). The degree of tissue damage of the torsioned ovaries decreased after a reperfusion period of 24 h in the torsioned ovaries. However, ovaries of both L-carnitine and NAC groups showed better recovery than the reperfusion group.Öğe VEGFR-1, Bcl-2, and HO-1 Ratios in Pregnant Women With Hypertension(Sage Publications Inc, 2015) Varol, Fusun; Uzunoglu, Renginar; Erbas, Hakan; Sut, Necdet; Sayin, CenkBackgound/Aim: Preeclampsia (PE) is a multisystem disease resulting in high maternal-fetal morbidity and mortality. The aim of the study was to investigate antiangiogenesis-associated alterations in antiapoptotic and antioxidative proteins in PE. Method: Of the 46 patients with PE, 25 (54.3%) were with gestational hypertension (GH), 12 (26%) were with mild, and 9 (19.5%) were with severe PE. The serum levels of vascular endothelial growth factor receptor 1 (VEGFR-1), heme oxygenase 1 (HO-1), and B-cell lymphoma/leukemia (Bcl-2) levels were measured by enzyme-linked immunosorbent assay. Results: In the severe PE group, the VEGFR-1 serum levels (27.3 16.8 vs 13.3 +/- 10.7 ng/mL, P = .023) were higher, but the Bcl-2 levels (1.5 +/- 0.2 vs 2.1 +/- 1.7 ng/mL, P = .047) were lower than the levels in the GH-mild PE group (P = .047). Also, VEGFR-1/Bcl-2 ratio in the severe PE group was significantly higher (P = .003) than the ratio in the GH-mild PE group. Conclusion: The Bcl-2 and HO-1 proteins seem to have important roles in the antiangiogenic environment of preeclampsia.