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11.
Oxidative stress is an important factor for aging. The antioxidative enzymes glutathione peroxidase (GPx), glutathione reductase (GRd) and superoxide dismutase (SOD) play a crucial role protecting the organism against the age-dependent oxidative stress. Glutathione (GSH) is present in nearly all living cells. GSH is one of the main antioxidants in the cell and it serves several physiological functions. Our purpose was to evaluate the age-related changes in mitochondrial GPx, GRd and SOD activities, and mitochondrial GSH pool in the brains of young (3months) and aged rats (24months). We also investigated whether melatonin administration influences these brain mitochondrial enzyme activities and GSH levels in young and aged rats. The results showed that GPx activity increased with age, whereas melatonin treatment decreased GPx activity in the aged rats at levels similar to those in young and young+melatonin groups. The activities of GRd and SOD, however, did not change with age. But, melatonin treatment increased SOD activity in the aged rats. GSH levels, which also increased with age, were not modified by melatonin treatment. The reduction in the SOD/GPx and GR/GPx ratios with age was prevented by melatonin administration. Together, our results suggest that the age-related oxidative stress in rat brain mitochondria is more apparent when the antioxidant enzyme ratios are analyzed instead of their absolute values. The antioxidative effects of melatonin were also supported by the recovery of the enzyme ratios during aging. 相似文献
12.
Local recurrence of renal cell carcinoma that simulated multiple renal arteriovenous fistulas after laparoscopic partial nephrectomy: Report of a rare case 下载免费PDF全文
Ahmet Murat Aydin Gonca Eldem Bora Peynircioglu Dilek Ertoy Baydar Cenk Yucel Bilen 《International journal of urology》2016,23(10):888-891
Herein we report a patient who was initially thought to have renal arteriovenous fistulas 3 months after laparoscopic partial nephrectomy for a small renal mass. After timely intervention using selective renal artery embolization, computed tomography 9 months post‐surgery showed persistent renal arteriovenous fistulas and nodular lesions in the perirenal fat. The patient then underwent radical nephrectomy, and histopathological examination showed underlying recurrent clear cell renal cell carcinoma invading the intraparenchymal arteries and veins, which was simulating multiple high‐flow renal arteriovenous fistulas. 相似文献
13.
Gonca Celik Didem Arslan Tas Dilek Altun Varmıs Aysegul Tahiroglu Ayse Avci 《Pediatrics international》2016,58(7):646-648
Vitamin D deficiency not only causes low bone mass but also may lead to neuropsychiatric disorders. In the present case, vitamin D supplementation reduced obsessive–compulsive disorder (OCD) symptoms associated with streptococcal infection in a 7‐year‐old boy. Sudden onset of symptoms, including excessive hand washing and fear of touching anything, had occurred 1 month before presentation. Although there are few studies on a possible causal relationship between vitamin D and neuropsychiatric disorders, the present report; together with previous data, suggest an etiological role of vitamin D‐related immune processes. 相似文献
14.
Keles GC Cetinkaya BO Ayas B Isildak I Diraman E Koprulu H Acikgoz G 《Clinical oral investigations》2007,11(4):369-376
The hypothesis, a relationship between gingival tissue platelet activating factor (PAF) levels and healing after periodontal
surgery, was tested by measuring PAF levels in gingival tissues collected from sites that had undergone flap surgery and guided
tissue regeneration (GTR) or flap surgery alone. Using a split-mouth design, 20 intrabony defects were randomly assigned to
treatment with flap surgery and GTR (group 1) or with flap surgery alone (group 2). Gingival tissue samples were obtained
at surgery (baseline) and at 6-month follow-up evaluation visit. One half of each sample was used for analysis of PAF levels
by high-performance liquid chromatography, and the other half of the sample was used for histomorphometric analysis that included
measurements of number and diameter of blood vessels. PAF levels and diameter of blood vessels were significantly decreased
(p < 0.01), and the number of blood vessels was significantly increased (p < 0.05) in both groups after 6 months compared to the baseline values. Postoperative number of blood vessels were significantly
higher in group 1 (p < 0.05), whereas there was no significant difference in postoperative PAF levels between the two groups (p > 0.05). Based on the reported results, it is suggested that a decrease in gingival PAF levels might be found after conventional
and regenerative periodontal surgery. 相似文献
15.
Cetinkaya BO Keles GC Ayas B Aydin O Kirtiloglu T Acikgoz G 《Clinical oral investigations》2007,11(1):61-68
Guided tissue regeneration is based on preventing the more rapidly proliferating epithelium from growing into the periodontal
defect after surgical procedures incorporating barrier membranes. The aim of this study was to compare the proliferative activity
of gingival epithelium using proliferating cell nuclear antigen (PCNA) as a marker of cell proliferation after surgical treatments
with bioactive glass graft material and bioabsorbable membrane. Using split mouth design, 20 intrabony defects were randomly
assigned treatments with bioactive glass (BG group) or bioabsorbable membrane (BM group). Gingival biopsies were taken at
preoperative and postoperative 12 weeks. After histological processing, the number of the inflammatory cells was measured
in hematoxylin and eosin-stained sections; PCNA expression was determined in immunohistochemically-stained sections. At postoperative
12 weeks, the number of the inflammatory cells was significantly decreased (p < 0.01), PCNA expression was significantly increased (p < 0.001) in both treatment groups compared to baseline data. There was no significant difference in PCNA expression between
baseline values of two groups (p > 0.05), while at postoperative 12 weeks, increase in BG group was significantly greater than that in BM group (p < 0.001). These results suggest that epithelial cell proliferation is more prominent after treatment of intrabony defects
with bioactive glass compared to the treatment with bioabsorbable membrane. 相似文献
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18.
Coronary artery thromboembolism: Unexpected presentation of left atrial myxoma covered with thrombus
Samet Uysal MD Ayse Zehra Karakoc MD Kadir Biyikli MD Benay Erden MD Ozkan Candan MD Gonca Gul Gecmen MD 《Journal of cardiac surgery》2020,35(8):2097-2099
Cardiac myxomas are benign primer cardiac tumors of the heart. They can be fatal with a thromboembolic presentation. Myocardial infarction is one of these unusual thromboembolic presentations. We report a patient who presented with cardiac arrest due to ventricular fibrillation related to myocardial infarction. After successful resuscitation, coronary angiography and transthoracic echocardiography were performed. A left atrial mass was observed and interpreted as a possible cause of coronary embolism leading to myocardial infarction. After surgical excision, the pathological examination confirmed myxoma, which was the essential cause of the tendency to arterial embolism. 相似文献
19.
Hasan Herken Mehmet Emin Erdal Ay?e Nur ?nci Kenar Gonca Ay?e ünal Burcu ?akaloz Mustafa Ertan Ay Erin? Yücel Tuba Edgünlü Cem ?engül 《Psychiatry investigation》2014,11(4):476-480
Objective
The synaptosomal-associated protein of 25 kDa (SNAP-25) gene is a presynaptic plasma membrane protein and an integral component of the vesicle docking and fusion machinery mediating secretion of neurotransmitters. Previously, several studies reported association between SNAP-25 and attention deficit hyperactivity disorder (ADHD). We investigated whether these SNAP-25 polymorphisms (MnlI T/G and DdelI T/C) were also associated with ADHD in the Turkish population.Methods
Our study comprised unrelated 139 subjects who met DSM-IV criteria for ADHD and 73 controls and all were of Turkish origin. Genetic analyses were performed and patients were evaluated with Wender-Utah Rating Scale and Adult ADD/ADHD DSM IV-Based Diagnostic Screening and Rating Scale.Results
SNAP-25 DdelI polymorphism was not associated with ADHD but there was a statistically significant difference between ADHD patients and controls for SNAP-25 MnlI polymorphism. For SNAP-25 MnlI polymorphism patients with G/G genotype of the SNAP-25 gene MnlI polymorphism had higher Wender-Utah scores and higher scores in the 1st and 3rd parts of adult ADD/ADHD Scale.Conclusion
We detected a significant association of the MnlI polymorphism in our ADHD sample which was similar to previous findings. Our study also revealed that SNAP-25 MnlI polymorphism was also associated with symptom severity of ADHD. This study is also, the first report on the association of SNAP-25 with ADHD in the Turkish population. 相似文献20.
Zeynep Pinar Keles Gonca Cayir Keles Bahattin Avci Burcu Ozkan Cetinkaya Gulnur Emingil 《Journal of periodontology》2014,85(9):1240-1246
Background: YKL‐40, a new acute‐phase protein, is shown to be elevated in inflammatory diseases, such as rheumatoid arthritis, type 2 diabetes mellitus, and coronary artery diseases. However, there is no data indicating a relationship between YKL‐40 and periodontal disease. Interleukin‐6 (IL‐6) is the major regulator of acute‐phase protein synthesis and one of the most studied inflammatory markers in periodontal disease. The purpose of the present study is to evaluate YKL‐40 and IL‐6 levels in gingival crevicular fluid (GCF) and serum of patients with periodontal disease and healthy individuals. Methods: Periodontally healthy individuals (n = 15), patients with gingivitis (n = 15), and patients with severe chronic periodontitis (CP) (n = 15) without any systemic disease were included in the study. Clinical measurements were recorded; GCF and blood samples were obtained from each participant. GCF and serum YKL‐40 and IL‐6 levels were analyzed by enzyme‐linked immunosorbent assay. Statistical analysis was performed by parametric and non‐parametric tests. Results: Total amounts of YKL‐40 and IL‐6 in GCF as well as serum YKL‐40 and IL‐6 levels were significantly higher in patients with gingivitis and CP compared with healthy controls (P <0.01). YKL‐40 levels in GCF and serum as well as serum IL‐6 levels were significantly higher in patients with CP compared with patients with gingivitis (P <0.01). Conclusions: YKL‐40 levels in GCF as well as serum YKL‐40 and IL‐6 levels increased from gingivitis to periodontitis. Within the limits of the present study, the YKL‐40 molecule might be a potential novel inflammatory marker of periodontal disease. 相似文献