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1.
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   
2.

Introduction  

Ethanol has a suppressive effect on inflammation and the immune system, but the effect of ethanol on tendon healing in vivo has not been studied. The purpose of this study was to investigate the histological and biomechanical effects of ethanol intake on tendon healing in a rat tendon injury model.  相似文献   
3.
Tranilast is an antiallergic drug that interferes with proliferation and migration of vascular smooth muscle cell induced by platelet-derived growth factor (PDGF) and transforming growth factor-beta1 (TGF-beta1). We investigated the local effect of tranilast on neointimal hyperplasia using tranilast-coated prosthetic grafts. The inner sides of the thin-walled polytetrafluoroethylene (PTFE) grafts were coated with chitosan and tranilast containing chitosan solution. Wistar albino rats (32) were used in the study. Patches (1 x 2 mm) for vascular grafts were prepared. Three groups were tested: group 1 (n = 12; tranilast coated), group 2 (n = 10; adhesive-only film-layer-coated), and group 3 (n = 10; normal ePTFE patch grafts sutured to the carotid arteries of the rats). Recipient sites of the carotid arteries were excised 4 weeks after surgery. All sections were examined histologically for graft patency, thrombus formation, and neointimal thickness. Expression of PDGF, fibroblast growth factor, and TGF-beta1 on cross-sections of the neointima were evaluated by immunohistochemistry. No significant differences were found regarding mean neointimal thicknesses. PDGF and TGF-beta-1 expressions were significantly lower in group 1. Although a decrease in local effect of tranilast was observed for growth factor expressions at a drug concentration of 0.05 mg/cm(2), a significant reduction in neointimal hyperplasia was not achieved. The coating concentration of 0.05 mg/cm(2) may have been too low to produce an antiproliferative effect. Given our promising results, further studies are recommended and planned using different drug concentrations and time intervals.  相似文献   
4.
BACKGROUND: To evaluate transient pattern electroretinography (PERG) and pattern visual evoked potential (VEP) for the diagnosis, differential diagnosis and follow-up of optic nerve diseases. METHODS: Twenty-nine consecutive patients (14 female, 15 male) with the diagnosis of ischaemic optic neuropathy (n=14) and optic neuritis (n=15) were included in this study. Mean age of the patients with ischaemic optic neuropathy was 63.3+/-3.3 (60-78) years and the mean age of the patients with optic neuritis was 28.3+/-8.4 (19-43) years. In each patient ophthalmological examination and systemic evaluation were done and VEP and PERG were recorded. As a control group, VEP recordings of 35 healthy subjects were included. RESULTS: In the ischaemic optic neuropathy group (group 1), mean VEP amplitude (+/-SD) (1.96+/-0.95 microV) was found to be decreased significantly in the affected eyes in comparison to the control group and the unaffected eyes. The delay in latency (116.3+/-20.14 msec in the affected eyes compared with 101.31+/-6.19 msec in unaffected eyes) was statistically significant when compared with the healthy subjects. In the optic neuritis group (group 2), VEP amplitude was decreased (4.13+/-4.04 microV vs 6.97+/-3.35 microV and 6.97+/-4.43 microV) and latency was increased (122.59+/-20.09 msec vs 101.31+/-6.19 msec and 108.76+/-13.57 msec) in affected eyes significantly in comparison to the unaffected eyes and control group, respectively. Even though there were no significant differences for P50 latency and N95/P50 ratios between affected and unaffected eyes in both groups, N95 amplitude decreased significantly in the affected eyes of the ischaemic optic neuropathy patients and N95 latency was found to be decreased in optic neuritis patients. There was no correlation between VEP and PERG findings in both groups. CONCLUSION: VEP amplitude decreased significantly in ischaemic optic neuropathies while latency delay was more significant in patients with optic neuritis. PERG findings showed decreased N95 amplitude in ischemic optic neuropathy without associated latency changes.  相似文献   
5.
6.
Summary The excretion of thioethers was determined in the urine of workers involved in road paving operations and in the preparation of asphalt mixing in an asphalt plant. An occupationally nonexposed group served as control. From the results it was observed that there was no significant difference in urinary thioether levels between the exposed and nonexposed groups, however, smokers of both exposed groups had significantly higher urinary thioether levels than the nonexposed smoking workers. These results suggested that higher urinary thioether excretion could be only due to a difference in smoking behaviour. There were also significant differences in urinary thioether levels between the exposed smoking and nonsmoking workers. The authors suggest that these workers have a low mutagenic/carcinogenic risk and smoking is responsible for the majority of thioether excretion, as has been found by other investigators.  相似文献   
7.
Stress and sulfite can stimulate numerous pathways leading to an increased production of free radicals which generate a peroxidation cascade producing lipid peroxidation, protein oxidation, DNA damage and cell death, and contribute to the occurrence of pathologic conditions. The purpose of our study was to investigate the effects of stress and sulfite on visual evoked potentials (VEPs) and to examine the relationship between lipid peroxidation and VEP changes. Forty male wistar rats, aged three months were used. They were equally divided into four groups: control (C), the group exposed to restraint stress (R), the group treated with sulfite (S) and the group exposed to stress and treated with sulfite (RS). Chronic restraint stress was applied for 21 days (1h/day) and sodium metabisulfite (520 mg/kg/day) was given by gavage for the same period. All latencies of VEP components were prolonged in the R, S and RS groups with respect to the C group. Brain and retina TBARS levels were found to be increased in those groups compared to the C group. Our results strongly suggest that the latency prolongations of all VEP components may have resulted from the enhancement of lipid peroxidation. Correlation analysis between brain and retina TBARS levels and VEP latencies also support this conclusion. Our data in regard to latency prolongations of all VEP components in the stress group exposed to sulfite, reflected an additive effect of sulfite toxicity on VEP components. Therefore it could be suggested that chronic exposure to stress and sulfite together is associated with a considerable health risk.  相似文献   
8.
The protective effect of dietary fiber on human cancer has received great attention during the last decades. Because dietary fiber constitues a large group of complex polysaccharides with various solubilities, degrees of lignification, chemical compositions and structural arrangements, several mechanisms for their effects have been proposed. In this study, in vitro binding capacities of various dietary fibers (potato fiber and glucomannan) and dietary fiber constituents (pectic acid and cellulose) against indirect mutagen 2-amino-3-methyl-3H-imidazo (4,5-f) quinoline (IQ) and direct-acting mutagen sodium azide were investigated. Direct-acting mutagen sodium azide was not adsorbed to the dietary fiber and dietary fiber constituents at 0 C, pH 4.5 and 37 C, pH 7.0. However, indirect-acting mutagen 2-amino-3-methyl-3H-imidazo (4,5-f) quinoline (IQ) were sorbed by them in variable ratios at 0 C, pH 4.5 and 37 C, pH 7.0. The differences between the in vitro binding capacities of the samples at two experimental conditions were found to be statiscially significant (P < 0.01). IQ was not released from the dietary fibers and constituents in distilled water.  相似文献   
9.
Objective. PTSD and major depression occur frequently following traumatic exposure, both as separate disorders and concurrently. Although much of Turkey is under threat of severe earthquakes, risk factors for developing psychiatric disorders among Turkish children have not yet been studied. The aim of the study was to examine risk factors for PTSD and depression develpoment in children. Method. A total of 160 survivors (102 girls and 58 boys) severely impacted by Turkey's 7.4-magnitude quake participated in a psychiatric interview 6–20 weeks after the disaster. The mean age was 14.43. Logistic regression was used to test effects of pre-disaster, disaster-related and post-disaster factors on diagnoses, yielding odds ratios (OR). Results. CAPS indicated that 96 (60%) had PTSD, and psychiatric interview found 49 (31%) with depression. Children diagnosed with PTSD were more likely to have witnessed death (OR=2.47) and experienced an extreme parental reaction (OR=3.45). Children with depression were more likely to be male (OR=4.48), have a higher trait anxiety score (OR=1.12 for every additional point), sustain injury (OR=4.29), and have lost a family member in the quake (OR=10.96). Focusing on the 96 children with PTSD, those with comorbid depression were more likely male, have a higher trait anxiety score, and have lost of family member. Conclusions. Mental health professionals should offer support to children witnessing death or losing a family member in a disaster. The ability of the family to remain calm and reassuring also may be a key factor in preventing PTSD.  相似文献   
10.
Peer educators (PEs) have a significant role in providing education on various health issues like smoking, alcohol, and other substance use. This study aimed to determine the experiences and opinions of PEs regarding a peer education program. Using the qualitative research method, data were collected from the study sample, which consisted of 23 student PEs, via semi-structured focus group discussions. Three main themes were developed: the Perceived Efficacy of Peer Education, Suggestions Regarding a Peer Education Program, and Contribution of the Peer Education Program to PEs. This study showed that peer educators thought peer education to be a highly effective method for the prevention of substance abuse. To improve the effectiveness of the program, it was recommended that it be started during middle school instead of high school, that families and local institutions be involved in the program, and that the students be directed to participate in arts, sports, and social activities.  相似文献   
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