Biomedical subjects

Yasemin Delen Akçay

Publications and source records attributed to Yasemin Delen Akçay.

4 recordsLinked to original sources

PubMed2004

A modified method for preparing platelet-rich plasma: an experimental study.

PURPOSE: In this study, our aim was to prepare low-cost autogenous platelet-rich plasma (PRP) for use in minor bone grafting procedures. This was the preliminary study of an experimental study concerning augmentation of bony defects with a mixture of PRP and beta-tricalcium phosphate. MATERIALS AND METHODS: Venous blood was collected from marginal ear veins of New Zealand White rabbits in EDTA (K3) vacutainer tubes. Blood samples were divided into 2 groups, and PRP was prepared through 2 methods, 1 of which is a variant of the other. The 2 PRP preparation methods described in this study were modified from Landesberg et al (J Oral Maxillofac Surg 58:297, 2000) after several trials, because the platelet enrichment percentages we obtained using their method were very low. Complete blood counts of venous blood samples, PRP, and platelet poor plasma (PPP) were made. Statistical analyses were performed using SPSS for Windows (SPSS, Chicago, IL). RESULTS: It took approximately 30 minutes to prepare PRP with both methods. Platelet counts in PRP were increased with respect to venous blood platelet counts. The differences between the experimental groups and genders were evaluated statistically with Mann-Whitney U tests (P < .05). Correlations between the groups and genders were also evaluated (P < .05). CONCLUSION: It was experimentally shown that PRP with high platelet counts can be prepared using this modified method without the need for costly autotransfusion systems.

Animals↗

PubMed2004

Protection capacity against low-density lipoprotein oxidation and antioxidant potential of some organic and non-organic wines.

Current research suggests that phenolics from wine may play a positive role against oxidation of low-density lipoprotein (LDL), which is a key step in the development of atherosclerosis. Considering the effects of different wine-making techniques on phenols and the wine consumption preference influencing the benefical effects of the product, organically and non-organically produced wines were obtained from the grapes of Vitis vinifera origin var: Carignan, Cabernet Sauvignon, Merlot, Grenache, Columbard and Semillon. Levels of total phenols [mg/l gallic acid equivalents (GAE)], antioxidant activity (%) and inhibition of LDL oxidation [%, inhibition of diene and malondialdehyde (MDA) formation] were determined. Some phenolic acids (gallic acid, p-hydroxybenzoic acid, syringic acid, 2,3-dihydroxybenzoic acid, ferulic acid, p-coumaric acid and vanillic acid) were quantified by high-performance liquid chromatography equipped with an electrochemical detection carried at +0.65 V (versus Ag/AgCl, 0.5 microA full scale). The highest concentrations of gallic, syringic and ferulic acids were found in organic Cabernet Sauvignon; 2,3-dihydroxybenzoic acid in organic Carignan and p-coumaric and vanillic acids in non-organic Merlot wine. High levels of antioxidant activity (AOA), inhibition of LDL oxidation and total phenol levels were found in non-organic Merlot (101.950% AOA; 88.570% LDL-diene; 41.000% LDL-MDA; 4700.000 mg/l GAE total phenol) and non-organic Cabernet Sauvignon (92.420% AOA; 91.430% LDL-diene; 67.000% LDL-MDA; 3500.000 mg/l GAE total phenol) grape varieties. Concentrations of some individual phenolic constituents (ferulic, p-coumaric, vanillic) are correlated with high antioxidant activity and inhibition of LDL oxidation. The best r value for all examined characteristics was determined for gallic acid, followed by 2,3-dihydroxybenzoic, syringic, ferulic and p-coumaric acids. Negative correlation of vanillic with MDA and p-hydroxybenzoic acid with LDL were confirmed by principal component analysis (PCA) analyses. Red wines display a higher antioxidant activity (81.110% AOA) than white ones (19.512% AOA). The average level of LDL inhibition capacity in red wine was determined as 87.072% and for the white as 54.867%.

Antioxidants↗

PubMed2003

Contradictory effects of chlorpromazine on endothelial cells in a rat model of endotoxic shock in association with its actions on serum TNF-alpha levels and antioxidant enzyme activities.

We examined the effects of the phenothiazine derivative, chlorpromazine on thoracic aortic endothelial cell histology (14 h after LPS challenge) in a model of endotoxic shock in rats. Since excessive formation of tumor necrosis factor-alpha (TNF-alpha) and oxygen-derived free radicals contribute to endothelial injury in endotoxemia, we also evaluated the effect of the drug on the activities of antioxidant enzymes superoxide dismutase (SOD) and catalase in liver tissue in this model and tried to find out whether this possible effect was associated with a change in serum TNF-alpha levels (measured 90 min after chlorpromazine administration). Endotoxemia was induced by a single i.p. injection of lipopolysaccharide (LPS) (5 mg kg(-1) in 1.5 ml of saline; LPS from Escherichia coli serotype 055:B5, L-2880, Sigma Chemical Company). Electron microscopic evaluation of the aortas revealed that chlorpromazine (administered 30 min prior to LPS challenge), in smaller doses (3 mg kg(-1)) ameliorated the endothelial cell injury caused by LPS, whereas it caused deterioration of endothelial cell morphology in higher doses (10 and 25 mg kg(-1)). Chlorpromazine administration caused a significant reduction in serum TNF-alpha levels, which was correlated well with an increase in SOD activity in all drug doses (3, 10 and 25 mg kg(-1)). Catalase activity was increased only in the 25 mg kg(-1) chlorpromazine group.

Analysis of Variance↗

PubMed2003

Effects of iron(II) salts and iron(III) complexes on trace element status in children with iron-deficiency anemia.

Iron-deficiency anemia (IDA) is the most common nutritional deficiency in childhood throughout the world. Although it has been shown that IRA is associated with elevated plasma copper and depleted zinc levels in children, there are conflicting results on the effect of iron supplementation on the absorption of these elements. The aim of this study was to investigate the effects of ferrous and ferric iron supplementation on the trace element status in children (n=25, aged 8-168 mo) with IDA. Fourteen of them were treated with ferric hydroxide-polymaltose complex (Ferrum, Vifor, Switzerland) (6 mg/d in the first 3 mo for initial therapy and 3 mg/kg for 3 mo as maintenance); the others were treated with a ferrous sulfate complex (FerroSanol, Schwarz, Germany) (6 mg/d in the first 3 mo for initial therapy and 3 mg/kg for 3 mo as maintenance). Plasma copper, zinc, and ceruloplasmin levels as well as hematological parameters were determined at baseline and the first, third, and sixth month of the treatment period. The hemoglobin and iron levels of patients in both groups were higher in the first and sixth months compared to baseline. Although the ceruloplasmin levels were depleted (48.9 mg/dL vs 41.4 mg/dL, p=0.035) during ferrous iron treatment, the copper and zinc levels remained unchanged. On the other hand, ferric iron supplementation led to an increase in zinc levels in the sixth month of treatment (0.77 mg/L vs 1.0 mg/L, p=0.021). The plasma copper levels were lower in the ferrous iron-treated group at the end of the first month of treatment than in the ferric irontreated group (1.06 mg/L vs 1.29 mg/L, p=0.008). In conclusion, our data showed that copper and ceruloplasmin metabolisms were affected by ferrous iron supplementation, whereas ferric iron kept them to normal levels of zinc, possibly by affecting their absorption. We conclude that the copper and zinc status of patients with IDA should be taken into consideration before and after iron therapy.

Adolescent↗