Person: MERAL, İSMAİL
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Publication Metadata only Complex regional pain syndrome: A vitamin K dependent entity?(2010-09-01T00:00:00Z) Ediz, Levent; Hiz, Ozcan; Meral, Ismail; Alpayci, Mahmut; MERAL, İSMAİLComplex regional pain syndrome (CRPS) is the complication of some injuries, such as a fracture, which affects the distal end of the injured extremity characterized by pain, allodynia, hyperalgesia, edema, abnormal vasomotor and sudomotor activity, movement disorders, joint stiffness, regional osteoporosis, and dystrophic changes in soft tissue. Exact pathogenic mechanism of CRPS is still unclear. Suggested pathogenic mechanisms of CRPS are evaluated in four major groups consist of classic inflammation, hypoxic changes and chronic ischemia, neurogenic inflammation and sympathetic dysregulation. All of these suggested pathogenic mechanisms produced by inflammatory cytokines mediated by nuclear factor kappaB. Vitamin K is a family of structurally similar, fat-soluble, 2-methyl-1,4-naphthoquinones. Vitamin K exerts a powerful influence on bone formation, especially in osteoporosis. Fat in bone stores some vitamin K. Gamma-carboxylation of the glutamic acid in osteocalcin is vitamin K dependent. Osteocalcin plays a role in calcium uptake and bone mineralization. Osteocalcin, the most abundant non-collagenous protein in bone, is produced by osteoblasts during bone matrix formation. Because osteocalcin is not carboxylated in case of vitamin K deficiency at the distal site of fracture or injury, it cannot bind to hydroxyapatite causing osteoporosis. Fracture starts a local inflammatory process in the fracture site and adjacent tissues as seen in CRPS. Vitamin K was shown to suppress the inflammatory cytokines and NF-kappaB and prevent oxidative, hypoxic, ischemic injury (which have key role in both initiation and progression of CRPS) to oligodendrocytes and neurons. We hypothesized that vitamin K has a key role and modulatory effect in CRPS pathogenesis. Vitamin K deficiency at the distal site of fracture occurs because of diminished and slowed circulation, local immobilization after extremity fracture or injury and use of vitamin K store at the distal site of the injured extremity and in the circulation for fracture healing and bone remodelling. In case of vitamin K deficiency at the distal site of fracture, classic inflammation starts with fracture at the distal tissues could not be restricted and classic inflammation, hypoxic changes, chronic ischemia, neurogenic inflammation, sympathetic dysregulation, which are the pathogenic mechanisms of CRPS, and patchy osteoporosis which occur due to high level of under-carboxylated osteocalcin could not be prevented. Briefly vitamin K level decreases in the distal site of the injured extremity consequently resulting in patchy osteoporosis due to high level of under-carboxylated osteocalcin and unrestricted inflammation which are the cause for both initiation and progression of CRPS. (C) 2010 Elsevier Ltd. All rights reserved.Publication Metadata only FİZYOLOJİ(2019-02-01) MERAL, İSMAİL; ÜSTÜNOVA, SAVAŞ; MERAL, İSMAİL; ÜSTÜNOVA, SAVAŞPublication Metadata only Effects of Angiotensin IV on Learning-Memory and Hippocampal Oxidative Stress in Diabetic Rats(2019-12-01T00:00:00Z) KILIÇ, Aysu; ÜSTÜNOVA, SAVAŞ; ELİBOL, BİRSEN; Bulut, Huri; MERAL, İSMAİL; Sahin, Emine Gulderen; KILIÇ, AYSU; ÜSTÜNOVA, SAVAŞ; ELİBOL, BİRSEN; BULUT, HURI; MERAL, İSMAİLPublication Metadata only Protective effects of caffeic acid phenethyl ester and thymoquinone on toluene induced liver toxicity.(2019-05-01) Esrefoglu, MUKADDES; Bayındır, NİHAN; KURBETLI, N; Selek, S; Akbas, Tosunoglu; Meydan, SEDAT; OZTURK, OSMAN; Bulut, HURİ; Meral, I; MEYDAN, SEDAT; EŞREFOĞLU, MUKADDES; SELEK, ŞAHABETTİN; ÖZTÜRK, OSMAN; BAYINDIR, NİHAN; BULUT, HURI; MERAL, İSMAİLPublication Metadata only Role of Angiotensin TYpe I and II receptor Blockade in Ischemia/Reperfusion Injury of Isolated Rat Heart(2017-05-04) Kılıç, AYSU; ÜSTÜNOVA, SAVAŞ; Usta, Cansu; BULUT, HURİ; ÜYÜKLÜ, MEHMET; Demirci-Tansel, Cihan; MERAL, İSMAİL; Artumak, Elif; Gurevin-Gürel, Ebru; KILIÇ, AYSU; ÜSTÜNOVA, SAVAŞ; BULUT, HURI; ÜYÜKLÜ, MEHMET; MERAL, İSMAİLPublication Metadata only The Prolidase Activity, Oxidative Stress, and Nitric Oxide Levels of Bladder Tissues with or Without Tumor in Patients with Bladder Cancer(2017-10-01) Eryılmaz, Recep; Kavak, Servet; Meral, Ismail; Demir, Halit; Pirincci, Necip; Gunes, Mustafa; Taken, Kerem; MERAL, İSMAİLThis study was designed to evaluate the malondialdehyde (MDA), glutathione (GSH) and nitric oxide (NO) levels, and also prolidase, glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) enzyme activities in malignant and benign cancers of bladder tissue. A total of 59 patients admitted to our clinic due to microscopic or macroscopic haematuria, were prospectively included in the study. Because of some reasons (no request to participate in the study, the inability to reach, other malignancies, alcohol consumption, metabolic disease), eight patients were excluded from study. Of the 51 patients, 25 were bladder tumor patients, and 26 were patients without cancers. The bladder tissue samples were obtained from all patients under anesthesia (spinal, epidural or general) for the measurement of MDA, GSH and NO levels, and prolidase, GSH-Px and SOD enzyme activities. Among the patients with bladder cancers, 7 patients were females and 18 patients were males, with an average age of 68.4 +/- 2.49. Among patients without tumors, 6 patients were females and 20 patients were males, with an average age of 58 +/- 2.05. In patients with bladder tumors, the oxidants (MDA, NO, prolidase) were higher, and the antioxidants (SOD, GSH, GSH-Px) were lower than those in patients without tumors. It was concluded that the oxygen free radicals play a role in the etiology of bladder cancers similar to many other tumors and inflammatory conditions. Therefore, we assume that antioxidants may provide benefits in the prevention and treatment of bladder cancer.Publication Metadata only Effects of shock waves on oxidative stress in parotid gland of rat(2014-06-01) TURAN, Mahfuz; Garca, M. Fatih; Kavak, Servet; Gecit, Ilhan; Meral, Ismail; Demir, Halit; Cegin, Bilal; Bektaş, Hava; Cankaya, Hakan; MERAL, İSMAİLThis study was designed to investigate whether extracorporeal shock wave lithotripsy (ESWL) exposure to parotid gland produces an oxidative stress in parotid glands of rats. Twelve male Wistar-albino rats, 6 months of age with an average body weight of 250-300 g, were divided randomly into two groups, each consisting of six rats. The animals in the first group did not receive any treatment and served as control. The left parotid glands of animals in group 2 (ESWL treated) received a thousand 18 kV shock waves after anesthetizing the rats with 50 mg/kg of ketamine. The animals in both groups were killed 72 hours after the ESWL treatment, and the parotid glands were harvested for the determination of lipid peroxidation product malondialdehyde (MDA), antioxidant glutathione (GSH) levels and the activities of antioxidant enzymes such as superoxide dismutase (SOD), GSH-Px and catalase (CAT). It was found that MDA level increased in parotid glands of rats after the ESWL treatment. The SOD, GSH-Px and CAT enzyme activities, and the level of antioxidant GSH decreased in parotid gland of rats after the ESWL treatment. It was concluded that short-term ESWL treatment caused an increase in the free radical production and a decrease in the antioxidant enzyme activity in parotid glands of ESWL-treated rats.Publication Metadata only Kardiyovasküler Hastalıklarda Biyotinidaz ve TCA Enzim Aktivitelerinin İncelenmesi(2023-07-09) Sarıkaya U.; Çimen Y. A.; Taşlıdere B.; Selek Ş.; Açıkgöz N.; Meral İ.; SARIKAYA, UFUK; ÇİMEN, YASİN ALİ; TAŞLIDERE, BAHADIR; SELEK, ŞAHABETTİN; AÇIKGÖZ, NUSRET; MERAL, İSMAİLPublication Metadata only Effects of extracorporeal shock-wave lithotripsy directed at the parotid gland on oxidative stress parameters and some trace element levels in facial nerve of rats(2012-04-01T00:00:00Z) Kavak, Servet; Garca, M. Fatih; Gecit, Ilhan; Meral, Ismail; Cengiz, Nurettin; Demir, Halit; MERAL, İSMAİLIntroduction: This study was designed to assess the effect of extracorporeal shock-wave lithotripsy (ESWL) exposure of the parotid gland on oxidative stress and some trace element levels in the facial nerves of rats. Methods: Twelve male Wistar albino rats were divided into two groups, each consisting of 6 animals. The rats in the first group served as controls. The left parotid glands of animals in the second group were treated with 1000 18-kV shock waves while anesthetized with ketamine. The animals in both groups were euthanized 72 h after the ESWL treatment, and the right facial nerve was harvested for determination of oxidant/antioxidant status and trace element levels. Results: Lipid peroxidation product malondialdehyde (MDA) and antioxidant glutathione (GSH) levels increased, and the activities of antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px), decreased in the facial nerves of ESWL-treated rats. The levels of iron, lead, manganese, and cobalt increased, and magnesium, cadmium, and copper levels decreased. Conclusions: ESWL treatment of the parotid gland may increase lipid peroxidation and decrease antioxidant enzyme activity in adjacent tissues such as the facial nerve. It also causes a decrease or increase in many mineral levels of the facial nerve, which is an undesirable condition for normal physiological function. Muscle Nerve, 2012Publication Metadata only THE EFFECT OF DROSPIRENONE/ESTRADIOL TREATMENT ON CATALASE AND CARBONIC ANHYDRASE ENZYME ACTIVITIES, AND SOME MINERAL CONCENTRATIONS IN OVARIECTOMIZED RATS(2011-01-01T00:00:00Z) ALKIS, Ismet; Kavak, Servet; Meral, Ismail; Oto, Gökhan; Demir, Halit; MERAL, İSMAİLThis study was designed to investigate the effect of drospirenone/estradiol (Angeliq (R)) on erythrocyte CAT and CA enzyme activities, and serum Fe, Mg, Co, Cu, Zn, Pb, Mn and Cd concentrations in ovariectomized- and drospirenone/estradiol-treated rats. Forty Female Wistar-albino rats were divided randomly into four groups, each consisting of ten rats. The animals in the first group were not treated, and served as control. The animals in the second group were operated but not ovariectomized and served as sham group. The animals in the third group were operated, ovariectomized but not treated with drospirenone/estradiol and served as ovariectomized group. The animals in the fourth group were operated, ovariectomized and treated with 0.01 mg/kg 17 beta-estradiol and 0.02 mg/kg drospirenone daily, p.o. for four weeks. Blood samples were collected at the end of the application period for the determination of the erythrocyte catalase (CAT) and carbonic anhydrase (CA) enzyme activities as well as serum Fe, Mg, Co, Cu, Zn, Pb, Mn and Cd concentrations. It was found that although erythrocyte CAT enzyme activity decreased in sham group, CA enzyme activity increased in angeliq group. Serum Pb levels of angeliq group and serum Mg levels of sham, ovariectomized and angeliq groups decreased. Serum Co, Cu, Mn and Fe levels increased in angeliq group. There was no significant difference among groups with regard to the serum Cd or Zn levels. It was concluded that hormonal replacement therapy might provide beneficial effects on blood antioxidant enzyme activity, heavy metal and some trace element levels in menopause. However, more studies are needed to verify and clarify the relationship between the hormonal replacement therapy and blood antioxidant status and trace element levels in menopause.