Calcified embolism: a rare cause of cerebral infarction.

Calcified cerebral emboli (CCE) are a rare cause of stroke and these emboli can be identified on a CT scan of the brain performed for the initial evaluation of stroke. In this report we present a patient who developed a CCE following cardiac catheterisation that lodged in the left middle cerebral artery with resultant right hemiparesis and aphasia. The calcified embolus was seen on CT but could not be identified on MRI. Predisposing factors for CCE include angiography and valve or vessel wall calcification. The natural history and response to standard therapy in patients with CCE as compared with stroke of other aetiologies have not been studied until now. Increased awareness and ability to identify calcified emboli will help us to have an improved understanding of strokes resulting from CCE.

Estimation of salivary protein thiols and total antioxidant power of saliva in brain tumor patients.

BACKGROUND: The role of oxidative stress in the genesis of various types of cancers is well established. Several chemical, cell culture and animal studies also indicate that antioxidants may slow or even prevent the development of cancer. Brain is considered abnormally sensitive to oxidative damage as brain tissue has high rate of oxygen consumption, high lipid content and relatively low antioxidant defenses, compared to other tissues. MATERIALS AND METHODS: The study design chosen for the present study was cross sectional. The biochemical parameters that were estimated in saliva manually using spectrophotometric methods were ferric reducing antioxidant power (FRAP) assay--a direct measure of total antioxidant activity of biological fluids and protein thiols. The physical parameters of saliva that were also assessed were salivary flow rate, pH of the saliva and the osmolality of the saliva. RESULTS: The mean values of salivary flow rate and pH were significantly decreased among malignant and benign tumor patients whereas the salivary osmolality was significantly increased in both the groups of patients. The mean values of salivary FRAP were significantly reduced among malignant and benign tumor patients. However, the salivary protein thiols were significantly increased in these patients. CONCLUSION: Hence with these observations it can be concluded that in saliva, besides the physical characteristics, salivary FRAP and protein thiol levels are appropriate indicators of the antioxidant status in brain tumor patients.

Plasma protein oxidation in patients with brain tumors.

OBJECTIVE: Proteins can undergo numerous covalent changes on exposure to oxidants. Oxidative modification of protein in vivo may affect a variety of cellular functions. Protein oxidation in vivo is a natural consequence of aerobic life. Oxygen radicals and other activated oxygen species generated as byproducts of cellular metabolism or from environmental sources cause modifications to the amino acids of proteins that generally result in loss of protein function/enzymatic activity. It is now well known that reactive oxygen species (ROS) play a key role in human cancer development. Moreover, the brain is especially vulnerable to ROS mediated injury. METHOD: Therefore, in the present study, protein oxidation was assessed in the plasma of 17 patients with brain tumors and 16 age and gender-matched controls by measuring protein thiols and protein carbonyls spectrophotometrically. RESULTS: There was a significant decrease in protein thiols and carbonyls in malignant cases of brain tumors when compared with the control group. No significant change in protein thiols was noted in benign cases compared to controls. A comparison of levels in benign and malignant cases for both the parameters also showed no significant difference. DISCUSSION: Thus, free radical toxicity does lead to protein oxidation in patients with brain tumors.

Free radical toxicity and antioxidants in Guillain-Barre syndrome, a preliminary study.

BACKGROUND: The generation of reactive oxygen species (ROS) has been implicated in the pathogenesis of a vast array of disease processes including some neurological disorders. METHOD: Ten patients with Guillain-Barre syndrome (GBS) and 10 age and sex-matched controls were included in this study. The erythrocyte glutathione (GSH), superoxide dismutase (SOD) and malondialdehyde (MDA) levels, as well as plasma antioxidant vitamins C and E and serum glutathione-S-transferase (GST) levels were estimated spectrophotometrically. RESULTS: The plasma vitamin E and the serum total glutathione-S-transferase levels were markedly increased in both pre- and post-treated cases of GBS when compared to controls. The erythrocyte glutathione and malondialdehyde levels were significantly reduced in GBS cases when compared to normals. However, plasma vitamin C and erythrocyte superoxide dismutase were not altered when compared to controls. CONCLUSION: Free radical toxicity may have an influence in patients suffering from GBS.