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1.
Hale Sayan V Haktan Ozacmak Aysel Guven R Gulhan Aktas I Diler Ozacmak 《Journal of investigative surgery》2006,19(3):163-173
Erythropoietin exerts hematopoietic effects by stimulating proliferation of early erythroid precursors. Nonhematopoietic effects of erythropoietin have also been shown. It may act as a new angiogenic factor in wound healing. This study aimed to investigate the effect of systemic administration of recombinant human erythropoietin on wound healing in mice. Dorsal incisional wounds were performed in mice, which were then divided into two groups; a group treated for 7 days with recombinant human erythropoietin, and a control group. Sacrificing animals on day 7, the wound tissues were collected for analysis of wound breaking strength, malondialdehyde, a marker of lipid peroxidation, hydroxyproline, an index of reparative collagen deposition, reduced glutathione levels, and for histological evaluation. The immunohistochemical determination of vascular endothelial growth factor (VEGF) which is believed to be the most prevalent angiogenic factor throughout the skin repair process, was also studied. The treatment significantly increased wound breaking strength by decreasing malondialdehyde and increasing hydroxyproline levels on day 7 after wounding. No statistically meaningful change was observed in reduced glutathione content. VEGF was immunostained significantly more on wound tissue of treated animals compared to the control group. Recombinant human erythropoietin treatment may be effective in wound healing due to inhibition of lipid peroxidation, deposition of collagen, and VEGF expression in wound area. 相似文献
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Doppler ultrasound is known as a reliable technique, which demonstrates the flow characteristics and resistance of ophthalmic arteries. In this study, ophthalmic arterial Doppler signals were obtained from 106 subjects, 54 of whom suffered from ocular Behcet disease while the rest were healthy subjects. Multilayer perceptron neural network (MLPNN) employing delta-bar-delta training algorithm was used to detect the presence of ocular Behcet disease. Spectral analysis of the ophthalmic arterial Doppler signals was performed by least squares (LS) autoregressive (AR) method for determining the MLPNN inputs. The MLPNN was trained with training set, cross validated with cross validation set and tested with testing set. All these data sets were obtained from ophthalmic arteries of healthy subjects and subjects suffering from ocular Behcet disease. Performance indicators and statistical measures were used for evaluating the MLPNN. The correct classification rate was 96.43% for healthy subjects and 93.75% for unhealthy subjects suffering from ocular Behcet disease. The classification results showed that the MLPNN employing delta-bar-delta training algorithm was effective to detect the ophthalmic arterial Doppler signals with Behcet disease. 相似文献
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The synthesis of full and semi interpenetrating networks (IPNs) based on poly(dimethy1-siloxane) (PDMS)/polystyrene, PDMS/polybutadiene and PDMS/poly(glycerylpropoxytriacry-late) 1 1 Glycerylpropoxytriacrylate (GFTA): is described. PDMS was used as host polymer in most cases. PDMS networks were prepared with two prepolymers having different number-average molecular weights between junctions, M?c = 15 · l03 and M?c = 75 · l03. Physical properties of IPN samples such as stress-strain behaviour, swelling and glass transition temperature (Tg) were examined. IPNs of both PDMS/polystyrene and PDMS/poly(glycerylpropoxytriacrylate) exhibit superior mechanical and elastomeric properties with respect to pure PDMS network. Most of the IPN systems studied in this work display two Tgs and indicate phase separation. 相似文献
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In the study, the ameliorating effects of alfa lipoic acid (ALA) against doxorubicin-induced testicular apoptosis, oxidative stress and disrupted mitochondrial fusion were investigated in male rats. Rats were divided into four groups as control, doxorubicin (DOX), DOX + ALA and ALA. A single dose of 15 mg/kg DOX was administered i.p to the DOX and DOX + ALA groups. 50 mg/kg ALA was given to the DOX + ALA and ALA groups by oral gavage every other day. After 28 days, rat testes and serum samples were collected and analysed. Administration of DOX alone caused a decrease in body and relative testicular weights, seminiferous tubule diameter and germinal epithelium thickness, Johnsen's score and serum testosterone levels. DOX treatment led to severe testicular damage such as tubular degeneration, and atrophic tubules. Also, the activities of superoxide dismutase and glutathione peroxidase were reduced, while the level of malondialdehyde was increased in the testis. The mRNA levels of apoptotic-related genes (CASP3, TP53, BAX, BCL2) and apoptotic index were increased, while mitofusin-2 decreased. DOX caused an increase in CASP3 and a decrease in mitofusin-2 immunoreactivities. Treatment with ALA markedly improved all of DOX-induced biochemical, histochemical and molecular alterations in rat testis. Consequently, ALA has a therapeutic role in ameliorating DOX-induced testicular damage in rats. 相似文献
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Apoptosis, or programmed cell death, is a physiological cell suicide program mainly leading to selective elimination of useless cells. This mechanism is important for the homeostasis of the immune system and presumably plays a two-sided role in the pathogenesis of multiple sclerosis (MS). On the one hand, evidence has been provided that impaired apoptosis might result in increased numbers or persistence of activated myelin-specific T cells, thus inducing the pathophysiologic processes in MS. On the other hand, local tissue damage might involve apoptosis of glial and neuronal cells and lead to the clinical symptoms. Here, an overview is presented on the current knowledge of the role of apoptosis in the pathogenesis of MS, and implications for related therapeutic strategies are discussed. 相似文献
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Mehmet Tetikoğlu Serdar Aktas Hacı Murat Sagdık Sıla Tasdemir Yigitoglu Fatih Özcura 《Seminars in ophthalmology》2017,32(5):651-654
Aim: To evaluate the effect of the platelet indices on the stage of diabetic retinopathy (DR) and diabetic macular edema (DME). Methods: In this retrospective study, the mean platelet valume (MPV), Plateletcrit (PCT), platelet (PLT), and platelet distribution width (PDW) of 199 diabetic patients and 76 healthy subjects were enrolled. The participants were divided into four groups. The first group was healthy control; the second group consisted of diabetic patients without DR; the third group was nonproliferative DR (NPDR); and the fourth group was proliferative DR (PDR). Results: Significant differences were found only in MPV and PCT values between patients with diabetes and healthy participants (8.6±0.96 fL vs 8.32±0.9 fL, P=0.011, 0.216± 0.58 vs 0.202±0.52, P=0.038). Comparing the groups, a statistically significant difference in MPV values was found between groups 4 and 1 (8.91±.7 fL vs 8.32±0.9 fL P=0.001) and between groups 4 and 3 (8.91±.7 fL vs 8.42±0.9 fL P=0.014). The MPV values of patients with DME were significantly higher than those of diabetic patients without DME (8.87±0.80 fL vs 8.45±0.97 fL). Conclusion: High MPV values may be an important risk factor for the development of PDR and DME in patients with diabetic retinopathy. 相似文献