Lipoprotein oxidation, plasma total antioxidant capacity and homocysteine level in patients with multiple sclerosis

Free radical-mediated peroxidation of biological molecules, especially of lipids, is implicated in the pathogenesis of a number of diseases like multiple sclerosis. Low concentration of antioxidant vitamins: beta carotene, retinol, alpha tocopherol and ascorbic acid have been observed in serum or cerebrospinal fluid of multiple sclerosis patients. On the basis of these observations, we studied the potential lipoprotein oxidation and total antioxidant capacity in the pathogenesis of multiple sclerosis. Lipoprotein oxidizability for plasma in vitro, serum levels of autoantibodies against oxidized low-density lipoproteins, plasma total homocysteine levels with vitamin B-12 and folate, and plasma total antioxidant capacity were measured in twenty four patients with multiple sclerosis and twenty four healthy sex- and age-matched person as control. In multiple sclerosis patients during an attack, a significant increase in both in vitro lipid oxidizability for plasma and in the levels of autoantibodies against oxidized low-density lipoproteins, and a strong decrease in plasma total antioxidant capacity were detected. Plasma total homocysteine levels were significantly higher in multiple sclerosis patients whose plasma vitamin B-12 and folate levels were lower but not statistically significant, than controls. The present study indicates that lipoprotein oxidation may be important factor in the course of multiple sclerosis and in vitro measurements of plasma oxidation kinetics as an indication for lipoprotein oxidation might be useful as an additional tool for the clinical diagnosis of multiple sclerosis

Serum levels of antioxidant vitamins and lipid peroxidation in multiple sclerosis

We determined serum levels of ascorbic acid, beta-carotene, retinol and alpha tocopherol and lipid peroxidation (as estimated by thiobarbituric acid reacting substances (TBARS) generation) in 24 multiple sclerosis (MS) patients and 24 healthy sex- and age-matched person as control. The levels of four antioxidant vitamins were significantly lower in MS patients compared to controls (p < 0.05). TBARS levels were significantly higher in the patients of MS compared to the controls (p = 0.001). In MS patients, the levels of beta-carotene, alpha tocopherol and ascorbic acid correlated significantly with each other (r(2) = 0.689 - 0.779). It appeared that there was inverse correlation between the serum levels of ascorbic acid or beta-carotene, but not of alpha tocopherol or retinol, and TBARS levels in MS. The present study indicates that antioxidant vitamins (alpha tocopherol, beta-carotene, retinol and ascorbic acid) are decreased in sera of MS patients during an attack, and that this decrease may well be dependent on the increased oxidative burden as reflected by lipid peroxidation products. The role of antioxidant vitamin supplementation in prevention and/or treatment of MS remains to be explored

Preserving effects of melatonin on the levels of glutathione and malondialdehyde in rats exposed to irradiation

In this study we investigated whether pretreatment with melatonin was protective against the injury of the central nervous system(CNS) in rats receiving LD50 whole body irradiation. The wistar rats were randomized into four groups: i) the control group(CG), ii) melatonin-administered group(MG; 1 mg/kg body weight), iii) irradiated group (RG; 6.75 Gy, one dose), and iv) melatonin-administered and irradiated group (MRG). Blood samples were drawn from the rats 24 h after the treatment and plasma glutathione levels were assayed. Plasma glutathione level was significantly higher in RG than CG. The melatonin pretreatment prevented GSH increase induced by irradiation. Lipid peroxidation and glutathione levels of rat cerebral cortex were determined in all groups after 24 h. Cortical malondialdehyde (MDA) was significantly higher in the RG. The melatonin pretreatment prevented cortical MDA increase induced by irradiation. Cortical GSH was significantly lower in RG than the CG. The melatonin pretreatment prevented cortical GSH decrease induced by irradiation. Tissue samples were obtained from cerebral cortex and hypothalamus which also were affected by ionizing irradiation in the CNS and were evaluated with electron microscopy. Histopathological findings showed that LD50 whole body irradiation resulted in damage of the neuronal cells of CNS. The results obtained from this study demonstrated that pretreatment with melatonin prevented the damage that develops in CNS following irradiation. The beneficial effect of melatonin can be related to protection of the CNS from oxidative injury and preventing the decrease in the level of cortical glutathione

Medicolegal aspects of rhinology practice.

Objective: To investigate rhinology-related malpractice claims with the aim of optimising safe practice

Evaluation of receiver-stimulator migration in cochlear implantation using the subperiosteal pocket technique: a prospective clinical study.

Objective: This study aimed to evaluate migration of the receiver-stimulator after cochlear implantation using the subperiosteal pocket technique