Browsing by Author "Demir, Halit"

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Accelerated Atherosclerosis in Haemodialysis Patients; Correlation of Endothelial Function With Oxidative Dna Damage
(Oxford Univ Press, 2012) Kaya, Yuksel; Ari, Elif; Demir, Halit; Soylemez, Nihat; Cebi, Aysegul; Alp, Hakan; Beytur, Ali
Background. Accelerated atherosclerosis is the major cause of mortality in patients on chronic haemodialysis (HD). The aim of this study was to evaluate the relationship between oxidative DNA damage [8-hydroxy-2'-deoxyguanosine/deoxyguanosine ratio (8-OHdG/dG ratio)], oxidative stress biomarkers and endothelial function in HD patients as an indicator of atherosclerosis. Methods. Forty-four chronic HD patients without known atherosclerotic disease and 55 age- and sex-matched healthy individuals were included in the study. Plasma malondialdehyde (MDA) levels and 8-OHdG/dG ratio were determined as oxidative stress markers. Superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were measured as antioxidants. Endothelial function was assessed by ultrasonography. Results. 8-OHdG/dG ratio and MDA levels were higher in HD patients than controls while SOD and GPx activities were lower in HD patients compared to controls. Flow-mediated dilatation FMD% in HD patients were lower than the control group (7.28 +/- 0.79 versus 11.18 +/- 0.82, P < 0.001). There was a significant negative correlation between FMD% and 8-OHdG/dG ratio (r = -0.678, P < 0.01) and MDA levels (r = 0.517, P < 0.01), while there was a significant positive correlation between FMD% and SOD (r = 0.538, P < 0.01) and GPx levels (r = 0.720, P < 0.01). Conclusions. Our data have demonstrated that HD patients exhibit increased oxidative DNA damage and decreased antioxidant activity. We propose that endothelial function is negatively correlated with 8-OHdG/dG ratio and positively correlated with antioxidant enzymes. To our knowledge, this is the first study to demonstrate the inverse relationship between endothelial function and plasma oxidative DNA damage in HD patients.
Alopecia Areata Different View; Heavy Metals
(Wolters Kluwer Medknow Publications, 2019) Ozaydin-Yavuz, Goknur; Yavuz, Ibrahim Halil; Demir, Halit; Demir, Canan; Bilgili, Serap Gunes
Background: Alopecia areata (AA) is a noncicatricial alopecia affecting any hair-bearing area. Although AA is considered to be an autoimmune disease, oxidative stress has been shown to be an important factor in the etiology of AA. Trace elements are highly essential for humans since they form the building blocks of large molecules, function as the cofactors of enzymes, and have some key biological functions. The aim of this study was to investigate serum levels of heavy metals like iron (Fe), zinc (Zn), manganese (Mn), copper (Cu), magnesium (Mg), cobalt (Co), cadmium (Cd), and lead (Pb) in patients with AA. Materials and Methods: The study included a patient group of 30 with AA and a control group of 31 healthy individuals. Serum levels of heavy metals were measured using atomic absorption spectrophotometry. Results: The 30 patients included 17 (56.7%) men and 13 (43.3%) women with a mean age of 33.8 (range, 19-48) years. Serum Zn and Mn levels were significantly lower and serum Cd, Fe, Mg, Pb, Co, and Cu levels were significantly higher in the patient group compared to that of the control group (P<0.05 for all). Conclusion: The results indicated that low levels of Zn and Mn are associated with AA while other metals were normal. So Zn supplementation may have some beneficial effect in AA while Fe prescription is fruitless.
Alterations in Oxidative Stress Markers in Laryngeal Carcinoma Patients
(Lippincott Williams & Wilkins, 2018) Bozan, Nazim; Demir, Halit; Gursoy, Tulay; Ozkan, Huseyin; Duzenli, Ufuk; Sankaya, Eren; Cankaya, Hakan
Background: Data describing how laryngeal cancer affects oxidative stress markers and antioxidants are limited. This study investigated serum antioxidant enzyme activities and oxidative stress markers before and after laryngectomies in patients with laryngeal cancer. Methods: A total of 29 patients with laryngeal cancer and 25 healthy control subjects were enrolled. Serum malondialdehyde (MDA) levels and superoxide dismutase (SOD), glutathione peroxidase (GSHPx), catalase (CAT), paraoxonase (PON), and arylesterase activities were measured spectrophotometrically. Blood samples were obtained from each patient just before surgery and 1 month after a laryngectomy. Results: The serum PON, arylesterase, CAT, SOD, and GSHPx activities were significantly decreased (all p < 0.001) and serum MDA levels were significantly increased (p < 0.001) in patients with laryngeal cancer, compared with control subjects. In laryngeal cancer patients, the serum GSHPx and arylesterase activity levels increased significantly following laryngectomies (both p < 0.001), whereas the MDA levels decreased significantly (p = 0.007). Conclusion: In patients with laryngeal cancer, the oxidant/antioxidant balance shifted toward oxidative stress. In addition, following laryngectomies, laryngeal cancer patients had increases in serum antioxidant enzyme activities and decreases in oxidative stress markers. Copyright (C) 2018, the Chinese Medical Association. Published by Elsevier Taiwan LLC.
Altered Serum Levels of Elements in Acute Leukemia Cases in Turkey
(Asian Pacific Organization Cancer Prevention, 2011) Demir, Cengiz; Demir, Halit; Esen, Ramazan; Sehitogullari, Abidin; Atmaca, Murat; Alay, Murat
Objective: The purpose of the study was to compare serum concentrations of some elements [zinc (Zn), copper (Cu), manganese (Mn), magnesium (Mg), lead (Pb), iron (Fe), cadmium (Cd) and cobalt (Co)] in acute leukemia patients with those of healthy subjects. Methods: The study group consisted of newly diagnosed acute leukemia patients and the controls were matched for socioeconomic stauts and eating habits. The elements levels in the patient group were measured before treatment with an atomic absorption spectrophotometer. The selection criteria for the patients and controls were the lack of recent blood transfusion history and taking any medication with mineral supplement. Results: The acute leukemia group composed of 42 patients and there were 40 persons in the control group. There was no difference between the age of the two groups (p=0.239). Serum levels of Zn, Mg and Mn were significantly lower with acute leukemia than in controls (p<0.001, p=0.011, p<0.001, respectively), while Cu, Pb and Cd were significantly elevated (p=0.003, p<0.001, p<0.001, respectively). There were no significant differences regarding Co and Fe (p=0.323 and p=0.508, respectively) Conclusion: In this study, we found levels of Zn, Mg and Mn to be lowered and of Cu, Pb and Cd to be elevated in patients with leukemia. Further studies are needed to clarify the role of these elements in pathogenesis of acute leukemia.
Analysis of Levels of Trace Elements (Zn, Cu, Mg, Pb, Mn, Cd, Co, Fe) in Blood After and Before Operation in Overian Cancered Patients
(2014) Bilici, Mustafa; Demir, Halit
Bu çalışma Yüzüncü Yıl Üniversitesi Tıp Fakültesi Kadın Doğum Anabilim Dalı ve Van Bölge Eğitim Araştırma Hastanesine, Over Kanseri nedeniyle başvuran toplam 33 hastadan, ameliyat öncesi ve sonrasında alınan serum materyali kullanıldı. Yine aynı yaş grubuna yakın sağlıklı ve gönüllü 30 kadından alınan serum örneklerinden eser element, iz ve ağır metal düzeyleri tayin edildi. Over kanserli hastalarda ameliyat öncesi Kurşun, Mangan ve Demir düzeyleri ile Over kanserli hastalarda ameliyat sonrası Kurşun, Mangan ve Demir düzeyleri (p<0.001) arasında anlamlı bir fark bulundu. Over kanserli hastalarda ameliyat öncesi ve sonrasında Çinko, Bakır, Kadmiyum ve Cobalt düzeyleri arasında anlamlı bir fark bulunamazken (p>0.005), Over kanserli hastalarda ameliyat öncesi ve sonrasında Magnezyum düzeyleri (p=0.07) arasında anlamlılığa yakın bir fark bulundu. Sonuç olarak, Zn çok güçlü bir antioksidant element olduğu için hastalığın prognozunda önemlidir. Yine Mg, Mn ve Fe elementler overyum kanserlerinde önemli markırlar olabilir ve özellikle Mn hastalarda düşük olması overyum kanser riskini artırabilir. Ayrıca Zn, Cu, Mg, Pb, Mn, Cd, Co ve Fe gibi elementler over kanserinin patogenezinde önemli rol oynayabilir.
Analysis of the Influences of Short-Term Levosimendan Exposure on Oxidant/Antioxidant Status and Trace-Element Levels in the Physiological Status of the Thoracic Aorta of Rats
(Springer, 2012) Aydin, Cemalettin; Ay, Yasin; Basel, Halil; Kavak, Servet; Inan, Bekir; Bektas, Hava; Demir, Halit
The objective of this study was to evaluate the effect of levosimendan (chemical formula C14H12N6O) exposure on oxidant/antioxidant status and trace-element levels in the thoracic aorta of rats. Eighteen male Wistar albino rats were randomly divided into two groups of eight animals each. Group 1 was not exposed to levosimendan and served as a control. Levosimendan (12 mu g/kg) diluted in 10 ml 0.5 % dextrose was administered intraperitoneally to group 2. Animals of both groups were killed after 3 days, and their thoracic aortae were harvested for determination of changes in tissue oxidant/antioxidant status and trace-element levels. The animals in both groups were killed 72 h after levosimendan exposure, and thoracic aortae were harvested for determination of the lipid peroxidation product MDA and antioxidant GSH levels and the activities of antioxidant enzymes such as SOD, GSH-Px and CAT. It was found that MDA, GSH and CAT enzyme levels increased in thoracic aortae of rats after levosimendan administration. SOD and CA enzyme activities and the level of antioxidant GSH decreased in thoracic aortae of rats after levosimendan treatment. Pb, Cd and Fe levels of thoracic aortae were significantly higher (P < 0.001) and Mg, Mn, Zn and Cu were significantly lower (P < 0.001) in the levosimendan group compared to the control group. These results suggest that short-term levosimendan treatment caused an increase in free radical production and a decrease in antioxidant enzyme activity in thoracic aortae of levosimendan-treated rats. It also causes a decrease or increase in many mineral levels of the thoracic aorta, which is an undesirable condition for normal pharmacological function.
Antioxidant Activities (superoxide Dismutase, Catalase, Reduced Glutation) and Oxidative Stress (malondialdehyde) Levels in Individuals Successed With Covid-19 Disease
(2022) Kaçmaz, Raci; Demir, Halit; Karakılıç, Uzman Özge
Bu tez çalışmasında S.B.Ü. Van Bölge Eğitim ve Araştırma Hastanesi Covid-19 servisi ve Göğüs Hastalıkları Servisi'ne başvuran ve Covid-19 tanısı konulan hastalardan alınan serum örneklerinden bazı antioksidan aktiviteleri (SOD, CAT ve GSH) ile oksidatif stres (MDA) düzeyleri tayin edildi. Yapılan bu tez çalışmasında Covid-19 olan hastalarda SOD, CAT ve GSH aktiviteleri, sağlıklı kontrol grubu ile kıyaslandığında daha düşük bulundu (p<0.05). Hasta grubun serum MDA düzeyi kontrol grubu ile kıyaslandığında daha yüksek bulundu (p<0.05). Sonuç olarak; SOD, CAT ve GSH aktivitelerinin hastaların kanında düşük, serum MDA düzeyinin ise yüksek oluşu, Covid-19 hastalığını ağır geçirme riskini arttırıcı faktörü olarak değerlendirilebilir.
Assessment of Adenosine Deaminase (Ada) Activity and Oxidative Stress in Patients With Chronic Tonsillitis
(Springer, 2014) Garca, Mehmet Fatih; Demir, Halit; Turan, Mahfuz; Bozan, Nazim; Kozan, Ahmet; Belli, Aeyda Bayel; Cankaya, Hakan
To emphasize the effectiveness of adenosine deaminase (ADA) enzyme, which has important roles in the differentiation of lymphoid cells, and oxidative stress in patients with chronic tonsillitis. Serum and tissue samples were obtained from 25 patients who underwent tonsillectomy due to recurrent episodes of acute tonsillitis. In the control group, which also had 25 subjects, only serum samples were taken as obtaining tissue samples would not have been ethically appropriate. ADA enzyme activity, catalase (CAT), carbonic anhydrase (CA), nitric oxide (NO) and malondialdehyde (MDA) were measured in the serum and tissue samples of patients and control group subjects. The serum values of both groups were compared. In addition, the tissue and serum values of patients were compared. Serum ADA activity and the oxidant enzymes MDA and NO values of the patient group were significantly higher than those of the control group (p < 0.001), the antioxidant enzymes CA and CAT values of the patient group were significantly lower than those of the control group (p < 0.001). In addition, while CA, CAT and NO enzyme levels were found to be significantly higher in the tonsil tissue of the patient group when compared to serum levels (p < 0.05), there was no difference between tissue and serum MDA and ADA activity (p > 0.05). Elevated ADA activity may be effective in the pathogenesis of chronic tonsillitis both by impairing tissue structure and contributing to SOR formation.
Assessment of Heavy Metal and Trace Element Levels in Patients With Telogen Effluvium
(Wolters Kluwer Medknow Publications, 2018) Yavuz, Ibrahim Halil; Yavuz, Goknur Ozaydin; Bilgili, Serap Gunes; Demir, Halit; Demir, Canan
Background: Despite a multitude of studies, etiology of primary chronic telogen effluvium (TE) remains incompletely understood. Essential heavy metals are associated with beneficial effects in humans as well as in other living organisms. However, they may lead to toxic effects when the exposure exceeds the higher tolerable limits. We wanted to assess the heavy metal and trace element levels in patients with chronic TE. Materials and Methods: A total of 40 subjects with chronic TE were included in the study, and 30 healthy women served as control. General and dermatological examinations were taken up in all individuals. Those patients with positive hair pull test were evaluated with the help of a trichogram. The presence of >20% telogen hair as documented by trichogram was a requirement for the study inclusion. UNICAM-929 spectrophotometry device was used for determining serum trace element and heavy metal concentrations. Results: In spite of an absence of significant differences in terms of average Zn concentration, weight, or height between patients and controls, significant differences were noted for Cd, Fe, Mg, Mn, Pb, Co, and Cu (P<0.05). Conclusion: Our results suggest that heavy metals may play a causative role in the development of chronic TE. However, contrary to previous reports, zinc did not appear to play an important etiological role, while these patients had elevated serum iron levels.
Can We Reduce Oxidative Stress With Liver Transplantation
(Soc Medical Biochemists Serbia, 2021) Aydin, Mesut; Dirik, Yaren; Demir, Canan; Tolunay, Harun; Demir, Halit
Background: The aim of this study was to determine the levels of lipid peroxidation (MDA) and antioxidants such as reduced glutathione (GSH), catalase (CAT) and superoxide dismutase (SOD) in the blood serum of patients with cirrhosis and liver transplantation. Methods: In this study, serum malondialdehyde acid (MDA) levels, superoxide dismutase (SOD), reduced glutathione (GSH), and catalase (CAT) activities were measured spectrophotometrically and compared to the results of the healthy control group. Results: SOD, CAT and GSH activities were significantly decreased in the patient groups compared to the healthy control group (p<0.05). MDA levels were significantly higher in the patient group compared to the healthy control group (p <0.05). Conclusions: In conclusion, this study demonstrated that oxidative stress may play an important role in the development of liver cirrhosis and in liver transplantation. This study is the first one to show how MDA, SOD, CAT and GSH levels change in liver cirrhosis and liver transplantation, while further studies are essential to investigate antioxidant enzymes and oxidative stress status in patients with cirrhosis and liver transplantation.
Catalase and Carbonic Anhydrase Enzyme Activities, and Some Mineral-Heavy Metal Concentrations in Newborns With Congenital Malformations
(Ortadogu Ad Pres & Publ Co, 2011) Melek, Mehmet; Demir, Halit; Kirimi, Ercan; Meral, Ismail; Keskin, Siddik
Objective: The aim of this study is to evaluate the factors such as antioxidant condition and mineral-heavy metal level association that may play a role in development of congenital malformations. Material and Methods: Fifteen healthy neonates as control group and 15 neonates with various congenital malformations were included study. Erythrocyte cataly (CAT) which is an antioxidant enzyme, erythrocyte carbonic anydrase (CA) enzyme activities which play a important role in acid-base balance, serum copper (Cu), lead (Pb), zinc (Zn), cadmium (Cd), iron (Fe), manganese (Mn) and magnesium (Mg) were measured from venous blood samples of each subject. Results: Erythrocyte CAT enzyme activity, serum Zn and Fe levels were statistically significantly decreased (P<0.05) in the study group while serum Cu and Cd levels were statistically significantly high (P<0.05)in the study group when compared to the control group. A negative correlation between erythrocyte CA activity and serum Pb levels was found in the study group. In the control group, negative correlations were found between erythrocyte CAT activity and serum Pb levels; serum Mg and Cu levels; and serum Cd and Mn levels. In addition, in the control group a positive correlation between serum Zn and Cu levels; erythrocyte CA activity and serum Mn levels was found. Conclusion: Our results suggest that erythrocyte CAT enzyme activity and serum Cu, Zn, Fe and Cd levels may play a role in pathogenesis of congenital malformations. The oxidative stress that rise as a result of an imbalance between prooxidant and antioxidant reactions seems to be associated with congenital malformations. Further studies are needed to confirm the association of antioxidant condition and mineral-heavy metal levels in the pathogenesis of congenital malformations.
Catalase, Carbonic Anhydrase and Other Biochemical Parameters in Esophageal Cancers in Turkey
(Asian Pacific Organization Cancer Prevention, 2010) Demir, Halit; Akkus, Zeynel Abidin; Cebi, Aysegul; Cakir, Tahir; Izmirli, Mustafa
Purpose: The main aim of our investigation is to show possible changes in antioxidant balance and selected biochemical parameters in esophageal cancers. Materials and Methods: This study was performed for the determination of levels in 25 patients diagnosed as having cancer in the Yuzuncu Yil University (Medical Oncology) and 15 healthy volunteers at same department with negative cancer signs. Results: The activity levels of catalase of sick and health groups were 33.8 +/- 4.31 (EU/gHg)(-1), 122.4 +/- 31.7 (EU/gHg)(-1), respectively. Th differance between the average levels was significant (p<0.001). CA (carbonic anhydrase) activity was 2.19 +/- 0.12 (EU/gHg)(-1), 2.46 +/- 0.32 (EU/gHg)(-1) in groups at same order with no statistical significance (p>0.05). The levels of albumin, globulin, ferritin, ALT, LDH, glucose, CRP, AST and uric acid were also determined in sick and healthy groups: 4.04 +/- 0.24, 4.04 +/- 0.43 gr/dl (p>0.05); 4.46 +/- 0.82, 3.17 +/- 0.10g/dl (p>0.05); 175.4 +/- 29.1, 260.4 +/- 15.45g/dI (p<0.001); 12.7 +/- 1.13, 19.5 +/- 1.91 ng/ml (p<0.001); 317.6 +/- 13.8, 298.0 +/- 12.1 mg/dl (p>0.05); 106.5 +/- 12.1, 89.7 +/- 2.2 (p>0.05), 5.94 +/- 1.04, 4.41 +/- 0.28 U/L (p>0.05); 19.4 +/- 1.68, 19.5 +/- 1.91 mg/dl (p>0.05); 30.0 +/- 3.24, 10.5 +/- 0.64 mg/dl (p<0.01) respectively. Conclusions: Consequently, in diagnosis of esophageal cancer, CA, CRP, uric acid and antioxidant examinations may be very important factors. Additional studies are needed to further address this important issue.
Cerrahi Tedavi Yapılmış Kolon Kanserli Hastalarda Kemoterapi Öncesi ve Sonrası Tümör Belirleyicileri ve Bazı Biyokimyasal Parametrelerin İncelenmesi
(2010) Gür, Tuğba; Demir, Halit
Bu çalışmada, Yüzüncü Yıl Üniversitesi Tıp Fakültesi Eğitim Araştırma Hastanesi Medikal Onkoloji Anabilim Dalında kolon kanseri teşhisi konmuş toplam 40 hasta ve sağlıklı 29 kişi gönüllü olarak katılımı sağlandı, daha sonra kemoterapi öncesi ve sonrası tümör belirleyicileri ve bazı biyokimyasal parametreler incelendi. Kolon kanserli hasta ve sağlıklı bireyler arasında yapılan bu çalışmada karbonik anhidraz ve katalaz aktiviteleri, hasta gurubunda komoterapi öncesi ve kemoterapi sonrası ile sağlıklı bireyler arasında istatistiksel olarak anlamlılık bulundu (p<0.001; p<0.05). Kolon kanserli hasta ile sağlıklı bireyler arasındaki yapılan istatiksel analizde komoterapi öncesi ve kemoterapi sonrası kanserli hasta gurubu ile sağlıklı bireyler arasında albümin düzeyleri istatistiksel olarak anlamlı bulundu (p<0.001). Kolon kanserli hasta ve sağlıklı bireyler arasındaki yapılan istatiksel analizde kemoterapi sonrası kanserli hasta gurubu ve sağlıklı bireyler arasında globülin düzeyleri istatistiksel olarak anlamlı bulunmazken (p>0.05) yine kolon kanserli hastanın kemoterapi öncesi ve sonrası globülin düzeyleri istatistiksel olarak anlamlı bulundu (p<0.01). Kolon kanserli hasta ve sağlıklı bireyler arasındaki yapılan istatiksel analizde komoterapi öncesi, kemoterapi sonrası, kanserli hasta gurubu ve sağlıklı bireyler arasında CRP, fibrinojen, CA125, kreatinin, alkalen fosfataz, AFP ve ferritin düzeylerinde istatistiksel olarak anlamlılık bulundu (p<0.001). Glukoz düzeylerinde kanserli hasta kemoterapi öncesi, sonrası ve kontrol gurubu arasında istatistiksel olarak önemli derecede bir anlamlılık saptandı (p<0.001; p<0.01). LDH düzeylerinde kanserli hasta kemoterapi öncesi, sonrası ve kontrol gurupu arasında istatistiksel olarak önemli derecede bir anlamlılık bulunmamıştır (p>0.05). Kanserli hasta kemoterapi öncesi, sonrası ve kontrol gurupu AST ve amilaz düzeylerinde istatistiksel olarak önemli derecede bir anlamlılık saptanırken (p<0.05) fakat ALT düzeylerinde ise istatistiksel olarak önemli derecede bir anlamlılık bulunmadı (p>0.05). Yine kanserli hasta kemoterapi öncesi, sonrası ve kontrol gurupu arasında CA19-9 ve CA15-3 düzeylerinde istatistiksel olarak önemli derecede bir anlamlılık bulunurken (p<0.05; p<0.01) CEA düzeylerinde ise anlamlılık saptanmadı (p<0.05; p<0.001).Anahtar Kelimeler: Kolon kanseri, AST, ALT, karbonik anhidraz, katalaz.
Change of Antioxidant Enzyme Activities, Some Metals and Lipid Peroxidation in Alzheimer's Disease
(Carbone Editore, 2016) Arslan, Ayse; Tuzun, Fatma Aykan; Tamer, Sibel; Demir, Halit; Aycan, Abdurrahman; Demir, Canan; Gonullu, Edip
Introduction: Alzheimer's disease (AD) is a neurodegenerative disease characterized by progressive cognitive regression and memory loss. It has been claimed that oxidative stress and factors such as metal accumulation in the brain play important roles in the etiopathogenesis of the disease. Material and methods: The subjects of this study consisted of 24 individuals with Alzheimer's disease and 15 healthy agematched controls. Blood samples were withdrawn from the patients and healthy controls, and the activities of antioxidant enzymes SOD (Superoxide Dismutase), GSH (Glutathion), GSHPx (Glutathion peroxidase), GST (Glutathion S-Transferase) and MDA (Malondialdehyde) levels were determined by Spectrometer. Some metals and heavy metals were measured by atomic absorption spectrometry (AAS). Results: Biochemical analyses showed a significant decrease of the main enzymatic antioxidant defences (SOD, GSH, GST and GSHPx) and increased production of lipid peroxidation marker (MDA) in the serum of AD patients, compared to age-matched control group (p< 0.001). Also the levels of Zn, Mg, and Mn was lower and Fe, Pb, and Cd was higher in the patient group, compared to the control group. Serum Cu and Co levels did not differ significantly between the patient and control groups (p> 0.001). Conclusion: These results supports the theory that in AD there is a defect in the antioxidant defense system, which may lead to oxidative damage. Also alterations in some trace metals and their related enzymes may play a role of etiopathogenesis in AD.
Change of the Levels of Trace Elements and Heavy Metals in Threatened Abortion
(Lippincott Williams & Wilkins, 2019) Turan, Kasim; Arslan, Ayse; Uckan, Kazim; Demir, Halit; Demir, Canan
Backround: This study aimed to investigate the impact of changes in the serum levels of trace elements and heavy metals in threatened abortion, which is a common complication in early pregnancy. Earlier studies have shown that changes in the serum levels of some trace elements and increased serum concentrations of heavy metals are associated with spontaneous abortion; however, this relationship has not been fully clarified. Methods: The patient group consisted of 45 pregnant women diagnosed with threatened abortion. There were 40 healthy nonpregnant women in the control group. Blood samples were obtained from the patients and the healthy controls, and the concentrations of serum trace elements and heavy metals were measured using atomic absorption spectrophotometry. Results: Statistically significant decreases were found in the serum zinc (Zn), iron (Fe), magnesium (Mg) and manganese (Mn) levels, and significant increases were found in the serum copper (Cu), cadmium (Cd) and lead (Pb) levels in cases of threatened abortion in comparison to the controls (p < 0.001). However, there was no difference between the groups in terms of the serum cobalt (Co) levels (p > 0.001). Conclusion: Changes in the balance of some essential trace elements (especially decreases in Fe and Zn) and elevated concentrations of some toxic heavy metals in the blood may be important diagnostic and prognostic parameters for threatened abortion
Characterisation of Carbonic Anhydrase Purified From Erythrocytes of Van Cat (Felis Catus)
(Parlar Scientific Publications (p S P), 2013) Soyler, Muhammed; Demir, Halit; Celikezen, Fatih Caglar; Celik, Ismail; Akan, Zafer
Carbonic anhydrase plays different roles in various tissues. It is a key enzyme that regulates the acid-base homeostasis under both normal and pathological conditions. In this study, carbonic anhydrase (CA; E.C 4.2.1.1) was purified from erythrocytes of Van cat (Fells catus) by affinity chromatography. The purification rate was found to be 367.21-fold. SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) was used to control the purity of enzyme. Optimal pH, ionic strength, and temperature for enzyme activity were determined. Molecular weight of CA was identified to be about 30 kDa by SDS-PAGE. Optimal pH and temperature were 8.0 and 40 degrees C. The highest activity was found at a concentration of 0.12 M (NH4)(2)SO4 as ionic strength. The Van cat (Fells catus) is a unique and endemic species; therefore, the characterisations of carbonic anhydrase enzyme are crucial. This study will shed light to future studies regarding the Van cat.
Cinacalcet May Improve Oxidative Dna Damage in Maintenance Hemodialysis Patients: an Observational Study
(Springer, 2014) Ari, Elif; Kaya, Yuksel; Demir, Halit; Asicioglu, Ebru; Eren, Zehra; Celik, Eray; Arikan, Hakki
Oxidative stress is accepted as a non-classical cardiovascular risk factor in patients on maintenance hemodialysis (HD). The aim of this study was to evaluate the impact of cinacalcet on oxidative stress biomarkers, oxidative DNA damage (8-hydroxy-2'-deoxyguanosine/deoxyguanosine), endothelial function (FMD %) and carotid artery intima-media thickness (CIMT) in HD patients. Forty-two chronic HD patients with secondary hyperparathyroidism undergoing 60 mg/day cinacalcet treatment with a follow-up of 6 months and 38 age- and sex-matched healthy individuals were included in this prospective study. Plasma malondialdehyde (MDA) levels and 8-hydroxy-2'-deoxyguanosine/deoxyguanosine ratio (8-OHdG/dG) were determined as oxidative stress markers. Superoxide dismutase (SOD), paraoxonase (PON), catalase (CAT), carbonic anhydrase (CAN) and glutathione peroxidase (GPx) activities were measured as antioxidants. FMD % and CIMT were assessed by ultrasonography. MDA levels were decreased; SOD, PON, CAT, CAN and GPx activities were increased after 6 months of cinacalcet treatment in HD patients. Although CIMT remained stabile, there was a significant improvement in FMD % as well as a notable reduction trend in 8-OHdG/dG ratio after 6 months of treatment. Our data have demonstrated that cinacalcet improves oxidative stress, genomic damage, endothelial function and increases antioxidant protection in HD patients after 6 months of treatment.
Correlation Ima With Timi Frame Count in Slow Coronary Flow: Can It Be a Guide for Treatment
(Taylor & Francis Ltd, 2020) Babat, Naci; Kaya, Yuksel; Demir, Halit
Aim Coronary slow flow (CSF) is defined as late opacification in epicardial coronary arteries with no significant stenosis. The aim of this study is to evaluate the relationship between ischemia-modified albumin (IMA) by using Spectrophotometer in CSF. Methods Level of IMA was measured by spectrophotometer. CSF patients were chosen for the determination of IMA level. All obtained data were compared with control groups. Results Serum IMA levels increased in the CSF group. It was observed that there was a significant increase in IMA levels in patients with CSF when compared to controls (p < 0.05). Conclusion IMA may play a role in the pathogenesis of CSF. IMA levels in the serum can be considered as a marker to predict coronary slow flow. IMA level can be used as a guide for coronary slow flow. Also, as increases number square frame, value IMA Increases similarly. It was found that the severity of impotence was correlated with CSF. Therefore, the IMA level may be predictive of the course of treatment. This study is the first one to show the relationships of IMA in CSF. In addition, further studies should be performed on IMA in CSF patients.
The Correlation of Serum Trace Elements and Heavy Metals With Carotid Artery Atherosclerosis in Maintenance Hemodialysis Patients
(Springernature, 2011) Ari, Elif; Kaya, Yuksel; Demir, Halit; Asicioglu, Ebru; Keskin, Siddik
Changes in essential trace elements and heavy metals may affect the atherosclerotic state of patients on maintenance hemodialysis (HD). The aim of the study was to evaluate the relation between the serum levels of some trace elements and heavy metals (iron, zinc, manganese, copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio) and carotid artery intima-media thickness (CIMT) in HD patients. Fifty chronic HD patients without known atherosclerotic disease and 48 age- and sex-matched healthy individuals were included in the study. The serum levels of trace elements (iron, zinc, manganese, copper, and magnesium) and heavy metals (cobalt, cadmium, and lead) were measured by Atomic Adsorption Spectrophotometer (UNICAM-929). CIMT was assessed by carotid artery ultrasonography. The serum levels of iron, zinc, and manganese were lower; levels of copper, magnesium, cobalt, cadmium, lead, and copper/zinc ratio were higher in HD patients compared to controls. CIMT in HD patients were higher than the control group (0.64 +/- 0.11 vs 0.42 +/- 0.05, p < 0.001). There was a significant negative correlation between CIMT and serum levels of zinc (r = -0.70, p < 0.01), iron (r = -0.71, p < 0.01), and manganese (r = -0.47, p < 0.01), while there was a significant positive correlation between CIMT and serum levels of copper (r = 0.63, p < 0.01), magnesium (r = 0.77, p < 0.01), cobalt (r = 0.63, p < 0.01), cadmium (r = 0.48, p < 0.01), lead (r = 0.38, p < 0.01), and copper/zinc ratio (r = 0.68, p < 0.01). A linear regression analysis showed that serum levels of magnesium, cadmium, lead, and copper/zinc ratio were still significantly and positively correlated with CIMT. We propose that copper/zinc ratio, magnesium and toxic metals cadmium and lead are independent determinants of CIMT in maintenance HD patients without known atherosclerotic disease.
Correlations Between Oxidative Dna Damage, Oxidative Stress and Coenzyme Q10 in Patients With Coronary Artery Disease
(Ivyspring int Publ, 2012) Kaya, Yuksel; Cebi, Aysegul; Soylemez, Nihat; Demir, Halit; Hakan, Hamit A. L. P.; Bakan, Ebubekir
The correlation of coronary artery disease ( CAD) with pro-oxidant/antioxidant balance and oxidative DNA damage was investigated. Seventy-seven patients with CAD and 44 healthy individuals as control were included in this study. The comparative ratios of ubiquinol-10/ubiquinone-10, 8-hydroxy-2'-deoxyguanosine/ deoxyguanosine and the level of MDA measured by HPLC and the activities of GPX and SOD by colorimetric approach in blood samples obtained from patients with CAD were unraveled. 8-OHdG/dG ratios, serum MDA level and GPX activity were found significantly elevated level in serum of CAD patients compared to control group. The SOD activity was observed in stable levels in CAD patients. Ubiquinol-10/ubiquinone-10 ratio was significantly lower in patients with CAD than the controls. The positive correlation was observed between 8-OHdG/dG ratios in both MDA levels and GPX activity, while the significant negative correlation was seemed between the ratio of 8-OHdG/dG and ubiquinol-10/ ubiquinone-10 as well as MDA levels and ubiquinol-10/ubiquinone-10 ratio. We conclude that, both the disruption of pro-oxidant/antioxidant balance and oxidative stress in DNA may play an important role in the pathogenesis of coronary artery disease.