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Featured researches published by Birsen Aydemir.


Biological Trace Element Research | 2007

High Levels of Cadmium and Lead in Seminal Fluid and Blood of Smoking Men are Associated with High Oxidative Stress and Damage in Infertile Subjects

Ali Riza Kiziler; Birsen Aydemir; Ilhan Onaran; Bulent Alici; Hamdi Özkara; Tevfik Gulyasar; Mehmet Can Akyolcu

We measured the levels of malondialdehyde (MDA), protein carbonyls, glutathione S-transferase (GST) and reducte glutathione (GSH) in seminal plasma and spermatozoa from 95 subjects including 50 infertile patients to evaluate the association between oxidative stress and damage and the components of the anti-oxidant defenses in seminal plasma and spermatozoa of infertile subjects and concentrations of cadmium (Cd) and lead (Pb) in the blood and seminal plasma because of tobacco smoke exposure. The reactive oxygen species (ROS) in spermatozoa were also evaluated by luminol (5-amino-2,3-dihydro-1,4-phthalazinedione)-enhanced chemiluminescence assay. The sperm count, motility, and morphology in the smokers infertile group were found to be lower than those in the fertile male group and nonsmokers infertile group (p < 0.001). Concentrations of Cd, Pb, MDA, protein carbonyls, and ROS levels in the smokers infertile group were significantly higher than those in the fertile male and nonsmokers infertile male groups (p < 0.001). However, GSH levels and GST activities were decreased in the smokers infertile male group than those in the fertile male and nonsmokers infertile male groups (p < 0.001). The results indicate that smoking could affect semen quality and oxidative lipid and protein damage in human spermatozoa. From Pearson correlation analysis, positive correlations were demonstrated between the seminal plasma Cd and seminal plasma protein carbonyls and between seminal plasma Pb and spermatozoa ROS levels in smokers of the subfertile group, while there was a significant positive correlation between blood Cd and ROS levels in smokers of the fertile group. There was also a significant negative correlation of the Cd level of the blood and GSH levels of the sperm and seminal plasma. These findings suggest that cigarette smoking enhances the levels of Cd and Pb in seminal plasma and blood and the extent of oxidative damage associated with a decrease in components of the anti-oxidant defenses in the sperm of infertile males.


Biological Trace Element Research | 2006

Impact of Cu and Fe concentrations on oxidative damage in male infertility

Birsen Aydemir; Ali Riza Kiziler; Ilhan Onaran; Bulent Alici; Hamdi Özkara; Mehmet Can Akyolcu

Oxidative stress in the reproductive system is thought to have an effect on the fertilizing ability of sperm. The purpose of this study was to assess the interaction of iron (Fe) and copper (Cu) ions in suspected subfertile and fertile male groups and to find out the relationships of the semen parameters (sperm count, motility, and abnormal morphology), glutathione, malondialdehyde, and reactive oxygen species with these variables. Semen and blood obtained from 60 subfertile men and from 40 fertile volunteers were examined. The sperm count and motility in the subfertile male group were found lower than those in fertile male group (p<0.001). Cu levels in serum and seminal plasma in the subfertile male group were significantly higher than those in the fertile male group (p<0.001 and p<0.05, respectively). There was also a significant increase in the Fe level of seminal plasma in the subfertile male group (p<0.001). However, there was no significant difference in the Fe level of serum in the subfertile male group. In conclusion, these findings suggest that Cu and Fe might be mediators of the effects of oxidative damage and play an essential role in spermatogenesis and male infertility; the determination of Fe and Cu levels in serum and seminal plasma during infertility investigation is recommended.


Toxicology and Industrial Health | 2006

Lead and cadmium exposure in children living around a coal-mining area in Yatagan, Turkey

Gülçin Yapıcı; Günay Can; Ali Riza Kiziler; Birsen Aydemir; İsmail Hakki Timur; Ayşe Kaypmaz

The study was designed to determine asymptomatic lead poisoning prevalence and cadmium exposure of preschool children living in a coal-mining area in Yatağan, Mugla, Turkey. The research was conducted between May and June 2002. The study included 236 children (53.4% female and 46.6% male) who were identified among the healthy children between the ages of 6 months and 6 years, using a systematic sampling method, from the records of the local medical centre of Yatağan. Assessments of the levels of blood lead and cadmium were performed by an atomic absorption spectrophotometer, in the Department of Biophysics, Cerrahpaşa Medical Faculty. The mean age of females and males were 49±18 and 43±19 months, respectively. The mean blood lead level was 33.8±15.6 μg/dL in females and 38.8±16.0 μg/dL in males. The mean blood lead level of the males was significantly higher than the females (P<0.05). Correlation analysis showed a statistically significant negative correlation between blood lead level and age in both sex groups (r=-0.367, P< 0.001). The blood lead level was found to be > 10 μg/dL in 95.7% and > 20 μg/dL in 87.6% of all children. The mean blood cadmium level of all children was 1.31±0.72 mg/dL. The blood cadmium level was found to be >0.5 μg/dL, which is considered to be toxic, in 85% of all children. The difference in blood cadmium levels between sexes was not significant. A statistically significant negative correlation was found between blood cadmium level and age of all children (r=-0.382, P<0.001). Although it is not possible to understand from this study what proportion of the biological lead and cadmium burden results from mining waste and what proportion comes from other sources, such as paint and gasoline residue deposited in soil and air, these results do indicate that asymptomatic lead poisoning and cadmium exposure are significant problems in children living in the Yatağan area. In conclusion, environmental lead measurements (house dust, soil, drinking water and air) must be performed, the results must be compared with the normal limits, and precautions must be taken if necessary in the Yatağan area. Future public health research efforts should focus on reducing the excessive levels of lead and cadmium in the environment.


Biological Trace Element Research | 2012

Association of Pb, Cd, and Se Concentrations and Oxidative Damage-Related Markers in Different Grades of Prostate Carcinoma

Savas Guzel; Lebriz Kiziler; Birsen Aydemir; Bulent Alici; Süleyman Ataus; Abdullah Aksu; Haydar Durak

Prostate cancer is known to be affected by the heavy metal levels and oxidative damage of the body, yet there are very few studies which look into the way it occurs. The aim of this study was to determine whether blood and tissue lead (Pb), cadmium (Cd), and selenium (Se) levels are associated with oxidative damage in the context of prostate cancer progression and development. Seventy-nine patients comprising 25 patients with benign prostatic hypertrophy (BPH), 23 patients with malignant prostatic carcinoma (malign Ca), 16 patients with low-grade prostatic intraepithelial neoplasia (LGPIN), and 15 patients with high-grade prostatic intraepithelial neoplasia (HGPIN) diagnosed on the basis of their clinical profile, transrectal ultrasonography, and histopathology were included in this study. Cd and Pb levels in whole blood were found to be increased in patients with HGPIN compared with the BPH group; also, the levels of Cd in whole blood and tissue were found to be increasing in patients with malign Ca, unlike BPH patients. Moreover, the levels of malondialdehyde (MDA) in plasma and tissue were significantly increased in malign Ca, LGPIN, and HGPIN than those in BPH. However, the levels of tissue Pb were found to be decreasing in BPH, unlike the malign Ca and HGPIN patients, and the levels of tissue protein carbonyls in malign Ca were significantly lower than those in HGPIN. The levels of tissue reduced glutathione (GSH) in malign Ca were significantly lower than those in BPH. Additionally, the levels of Se in serum and tissue in LGPIN were significantly lower than those in BPH. The serum Se levels in HGPIN were also significantly lower than those in BPH and malign Ca groups. Furthermore, the concentrations of serum Se in LGPIN were significantly lower than those in malign Ca. From the Pearson correlation analysis, there were significant positive correlations between tissue Cd and MDA levels in malign Ca, LGPIN, and HGPIN and between the tissue Pb and tissue MDA and protein carbonyl levels in malign Ca. Blood Pb and tissue Pb were also significantly positively correlated with plasma MDA and protein carbonyl levels in malign Ca. In addition, blood Pb was significantly positively correlated with tissue MDA and protein carbonyl levels in malign Ca, and a significant positive correlation was also found between blood Cd and plasma protein carbonyls and tissue MDA in LGPIN. We observed that altered prooxidant–antioxidant balance and heavy metal levels may lead to an increase in oxidative damage and may consequently play an important role in prostate carcinogenesis. These findings indicate that changes in the levels of Pb, Cd, Se, MDA, protein carbonyls, and GSH in the blood and/or tissue are related to the prostatic carcinoma development and progression, although triggering one of the mentioned changes is unknown; therefore, further study is required to determine the exact steps of the process and clarify the roles of different substances in order to obtain a more detailed explanation of the phenomenon.


Annals of Vascular Surgery | 2010

The Role of Oxidative Stress and Antioxidant Defenses in Buerger Disease and Atherosclerotic Peripheral Arterial Occlusive Disease

Caner Arslan; Hakan Altan; Kazim Besirli; Birsen Aydemir; Ali Riza Kiziler; Şeyma Denli

The aim of this study was to determine the status and the role of oxidative stress and antioxidant defenses in patients with Buerger disease and atherosclerotic peripheral arterial occlusive disease (PAOD). Seventy-three subjects resembling each other in general characteristics were involved in the study: 21 with lower extremity PAOD (mean age 53.05 +/- 10.8 years, 17 men and four women), 22 with Buerger disease (mean age 38.59 +/- 6.4 years, 19 men and three women), and 30 healthy volunteers (mean age 38.59 +/- 6.4 years, 22 men and eight women). We measured the levels of plasma malondialdehyde (MDA), paraoxonase (PON1), protein carbonyls, arylesterase, nitric oxide (NO), serum oxidized low-density lipoprotein (ox-LDL) and MDA, glutathione (GSH), glutathione reductase (GSH-red), glutathione peroxidase (GSH-px), superoxide dismutase (SOD), and catalase (CAT) in erythrocytes. Plasma protein carbonyls, serum ox-LDL, and plasma and erythrocyte MDA were significantly high in the Buerger disease group compared to the PAOD and control groups (p < 0.001). Plasma PON1 levels and GSH and GSH-px levels in erythrocytes in the Buerger disease group were significantly low compared to the PAOD and control groups (p < 0.001). GSH-red, SOD, and CAT levels in erythrocytes in the Buerger disease group were significantly lowcompared to the PAOD group (p < 0.01, p < 0.001, and p < 0.001, respectively). NO levels were significantly lower in the PAOD group compared to the control group (p < 0.05). The balance between oxidative stress and antioxidant capacity is more seriously impaired in Buerger disease than PAOD.


Gynecological Endocrinology | 2013

The relationship between copper, homocysteine and early vascular disease in lean women with polycystic ovary syndrome

Cem Celik; Ercan Bastu; Remzi Abali; Seref Alpsoy; Eda Çelik Güzel; Birsen Aydemir; John Yeh

Abstract This study investigates copper (Cu) levels and vascular dysfunction in lean women with polycystic ovary syndrome (PCOS). 44 subjects with PCOS, diagnosed according to Rotterdam criteria, and 42 healthy subjects matched for body mass index and age. Comparison of serum Cu, homocysteine, carotid intima-media thickness (CIMT), brachial artery flow mediated dilation (FMD) was carried out between PCOS patients and the control group. Clinical study was done in Namik Kemal University School of Medicine. The CIMT and concentration of Cu in PCOS patients was significantly higher than the healthy controls. FMD levels in PCOS patients were significantly lower than those in controls. In PCOS patients, CIMT was correlated with estrogen and Cu levels. However, FMD was correlated with age and Cu levels. Among these contributing factors, Cu levels were correlated with a change in CIMT and FMD. CIMT and FMD in PCOS patients were related to Cu levels as well as several cardiovascular risk factors. Thus, increased Cu levels may be responsible for the increased risk of early vascular disease in women with PCOS.


Archives of Andrology | 2007

Relationships between levels of estradiol and testosterone in seminal plasma and GSTM1 polymorphism in infertile men.

Ilhan Onaran; Birsen Aydemir; Ali Riza Kiziler; T. Demiryurek; Bulent Alici

Glutathione S-transferase M1 (GSTM1) enzyme serves as a steroid-binding protein by its ability to bind to testosterone and estradiol. The levels of total estradiol and testosterone were measured by using an electrochemiluminescence immunoassay in serum and seminal plasma from 103 subjects including 62 subfertile patients. GSTM1 polymorphism was examined using polymerase chain reaction. The estradiol and testosterone levels in seminal plasma were not different in control and subfertile subjects. No role for GSTM1 enzyme as a steroid-binding protein seemed likely as there was also no significant difference in seminal plasma estradiol and testosterone levels according to GSTM1 genoytpe. Significant positive correlations were found between seminal estradiol and serum estradiol in infertile males, and between seminal testosterone and serum testosterone in fertile males, independent of GSTM1 genotype. GSTM1 polymorphism is not a genetic risk factor of seminal estradiol and testosterone levels in infertile males although further studies are warranted.


Gastroenterology Research and Practice | 2012

Paraoxonase and arylesterase activities, lipid profile, and oxidative damage in experimental ischemic colitis model.

Ethem Unal; Cengiz Eriş; Bülent Kaya; Hafize Uzun; Faruk Cavdar; Murat Yildar; Ali Riza Kiziler; Birsen Aydemir; Pembegul Gunes; Riza Kutanis; Izzet Titiz

Objective. In the present study, since PON1 is known as an HDL-associated antioxidant enzyme that inhibits the oxidative modification of LDL and oxidative stress plays a role in the pathogenesis of mesenteric ischemia, we investigated the changes in PON1 activity and lipid profile in an experimental ischemic colitis model. Methods. Forty male Wistar albino rats were divided into two groups: the control group (N = 15) and the experimental group (N = 25). All animals were anesthetized with ether and ketamine anesthesia to undergo a midline laparotomy. Ischemic colitis was induced by marginal vessel ligation in the splenic flexura (devascularization process). A sham laparotomy was performed in the control group. All animals were sacrificed on the seventh postoperative day. Oxidative stress marker (malonyldialdehyde, MDA), lipid profile, and paraoxonase (PON-1) and arylesterase activities were determined. Histopathological evaluation was done under light microscopy, after sectioning and staining with hematoxyline and eosin. Statistical analysis was conducted using Students t-test and Mann-Whitney U test, and P < 0.05 was considered as statistically significant. Results. There was a significant decrease in both serum and tissue PON1 activity in ischemic colitis group (P < 0.01, for each). Similarly, arylesterase levels showed a parallel decrease in both tissue and serum of the experimental group (P < 0.01 and P < 0.001, retrospectively). MDA, an oxidative stress marker, was seen to increase in the experimental group (P < 0.01, tissue; P < 0.05, serum). In experimental group, there was a significant rise in serum total cholesterol and LDL levels (P < 0.001, for each). However, HDL level decreased significantly (P < 0.001). Triglycerides did not show any change between the groups (P > 0.05). Conclusions. PON1 and arylesterase play an important role in the pathophysiology of ischemic colitis.


Medicinal Chemistry | 2007

Effect of Alpha-lipoic Acid Supplementation on Trace Element Levels in Serum and in Postmitotic Tissue in Aged Rats

Refik Kayali; Ufuk Çakatay; Ali Riza Kiziler; Birsen Aydemir

Redistribution of redox-active divalent metal ions (e.g. copper, zinc, and iron) in postmitotic tissues of lipoic acid supplemented aging rats has been proposed to contribute to metal-catalyzed protein oxidation. DL-alpha lipoic acid (LA) (100 mg/kg body wt/day) was administered intraperitoneally to the Sprague-Dawley rats for 14 days. Serum copper levels lowered in the aged rats with LA supplementation compared to the rats without LA supplementation. On the other hand, serum zinc and iron levels increased in the aged rats with LA supplementation compared to the rats without LA supplementation. Copper levels of the postmitotic tissues were not changed in the aged rats with LA supplementation compared to the controls. The heart zinc levels detected in LA supplemented rats were significantly lower than controls. Similarly, the iron levels of the heart were found to be significantly lower in LA supplemented rats when compared to control rats. LA supplementation did not affect brain and muscle iron levels. The brain and muscle zinc levels remained the same in both group of rats. Based on the findings of our study, we have concluded that LA may exhibit prooxidant effect depending on the altered trace element homeostasis. Therefore, our results emphasize the importance of monitoring the dose of LA supplementation, duration of treatment and its potential harmful effects in the postmitotic tissues of aged rats.


Journal of Genetics | 2017

Association of NFKB1A and microRNAs variations and the susceptibility to atherosclerosis

Tuba Oner; Caner Arslan; Guven Yenmis; Berk Arapi; Cigdem Tel; Birsen Aydemir; Gönül Sultuybek

Atherosclerosis (AT) is a chronic immuno-inflammatory disease characterized by inflammatory mediators and immune activation in arterial wall. Although NF-

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