Plasma concentrations of lipid peroxidation products in children with acute leukaemia.

Acute leukaemia is the most common childhood malignancy. The cause of leukaemia is not known in most of the cases and of late free radicals have been implicated in the pathogenesis of leukaemia. The degree of lipid peroxidation was studied in the present study as a marker of disease activity in 15 patients of acute lymphoblastic leukaemia and 20 healthy age and sex matched individuals served as control. Serum malonaldehyde (MDA) levels were increased in leukaemia and were higher in the active phase of disease as compared to those in remission, Hence, serum MDA estimation in leukaemia can be of help in diagnosis and to predict the chances of relapse.

Role of oxygen free radicals in shock.

AIMS OF THE STUDY: To study lipid peroxidation, magnesium levels (Mg) in plasma and red cells (RBC), superoxide dismutase (SOD) and catalase (CAT) activities in the plasma and RBC of shock patients. METHODOLOGY: Twenty five patients with clinically defined septic shock and 30 healthy volunteers were selected for the study to study the parameters of oxidative stress. RESULTS: Septic shock patients had higher activities of plasma and RBC SOD and CAT activities as compared to control. Also, plasma Mg and malonaldehyde (MDA) levels were higher in shock patients as compared to controls. While, RBC Mg levels were similar in two groups. CONCLUSIONS: The finding of increased concentration of MDA, Mg, SOD and CAT in sepsis implicates oxygen free radicals in the pathophysiology and free radical scavengers may have a role in organ preservation.

Oxidative stress after acute myocardial infarction: effect of thrombolytic treatment.

OBJECTIVE: Treatment with thrombolysis plays a crucial role in salvaging the myocardium in myocardial infarction (MI) patients, but reperfusion of ischaemic areas may itself be associated with reperfusion injury mediated by free radical induced oxidation. Hence the present study was planned to evaluate oxidative stress in patients receiving thrombolytic therapy during MI and to compare them with those not receiving thrombolysis. METHODS: Thiobarbituric acid reactive substance (TBARS) was used as a marker of lipid peroxidation in 30 patients after acute MI. Thirteen were treated by intravenous thrombolysis and 17 served as control. Also, vitamin E levels were estimated in these patients. RESULTS: Patients treated with thrombolysis showed a fall in vitamin E and increase in TBARS within first hours. The decrease in vitamin E was independent of a change in cholesterol. However, the levels were similar at 72 hours. CONCLUSION: The results indicate increased free radical production after MI and reperfusion also increases in free radical production and antioxidants may have a part in improving thrombolytic reperfusion of ischaemic myocardium.

Magnesium deficiency potentiates free radical production associated with myocardial infarction.

OBJECTIVE: Oxidative injury and magnesium deficiency may accompany cardiovascular disease states and the study was planned to find out whether magnesium deficiency promotes oxidative injury. METHODS: Serum malonaldehyde (MDA), magnesium, vitamin E and total glutathione levels (GSH) were estimated in 22 patients with acute myocardial infarction and 15 healthy controls. RESULTS: Low levels of Mg, GSH, vitamin E and elevated levels of MDA were observed in patients of acute myocardial infarction. Statistically significant correlations were observed between Mg and MDA, MDA and GSH, Mg and vitamin E. CONCLUSION: Our findings suggest that Mg deficiency can potentiate oxidative injury to post ischaemic myocardium and that antioxidants may have a role in protection against the prooxidant influence(s) of Mg deficiency.

Glutathione levels in health and sickness.

We speculate that the glutathione (GSH) status of human subjects could be an indicator of health and functional age. In this regard, in a study in which, 80 young and 40 elderly healthy individuals were selected as control. We also studied 145 patients with chronic illnesses namely, ischaemic heart disease, diabetes, preeclampsia, cataract, chronic renal failure and leukaemia (age 52 +/- 8.6 years). We observed that all the subjects had high malonadildehyde and low glutathione levels as compared to control. These early observations support the hypothesis that oxidative stress may have an important aetiological rule and antioxidants a potential therapeutic role.

Serum vitamin E in chronic myeloid leukaemia.

OBJECTIVE: Experimental evidence suggests that free radicals can participate in tumour promotion and malignant conversion and free radical scavengers like alphatocopherol act as first line of defense against peroxidation of polyunsaturated fatty acids. The present study was planned to estimate serum vitamin E levels in patients of chronic myeloid leukaemia (CML). METHODS: Serum vitamin E levels were estimated in 25 CML patients before and after the treatment. Twenty five age and sex matched healthy individuals served as control. RESULTS: Mean serum vitamin E levels were significantly decreased in CML patients before starting the treatment as compared to control. Also, vitamin E levels increased significantly after the treatment, but, remained lower than the control. CONCLUSION: Vitamin E levels were lower in CML patients as compared to control and the levels increased significantly after treatment in these patients. This could be due to decrease in oxidative stress due to decrease in tumour load.

Immunological assessment in patients of leukaemia.

In the present study delayed cutaneous hypersensitivity response (DNCB test) and humoral response (by uantification of immunoglobulins) ware carried out in 20 cases of leukaemias. None of the cases was found to be anergic or immunodeficient. In remission also patients showed the normal response.

Distribution of blood viscosity values and biochemical correlates in healthy adults.

OBJECTIVE: Increase in the viscosity of blood predict clinical manifestation of atherothrombotic vascular disease. The clinical utility of viscosity measurements in cardiovascular risk factor requires a reference value established from a healthy disease free population. METHODS: Blood viscosity (based on empirical Merill's formula), fibrinogen, haematocrit and lipid profile were measured in 100 fasting healthy nonsmoking adults (50 men, 50 women). RESULTS: The mean (+/- SD) blood viscosity values were 0.030 +/- 0.015 dyne/cm2. Men had higher viscosity values than women. Also, men had higher triglycerides, haematocrit as well as fibrinogen as compared to women. CONCLUSION: This study provides reference values for the blood viscosity, fibrinogen haematocrit and lipid profile. Viscosity measurements may improve identification and risk stratification of patients at high risk for atherothrombotic vascular disease and its complications.

Alpha tocopherol concentration in serum of critically ill patients.

OBJECTIVE: Alpha tocopherol is the biologically and chemically active form of vitamin E and is the most abundant lipid-soluble antioxidant in humans protecting the cell membranes. Serum concentration of the antioxidant alpha tocopherol was measured in critically ill patients in whom the excessive generation of reactive oxygen species could compromise antioxidant defence mechanisms. METHOD: Alpha tocopherol concentration in serum was measured spectrofluorometrically in critically ill patients admitted in intensive care unit and age matched healthy adults, patients with diabetes mellitus (DM) and chronic myeloid leukaemia (CML) served as control. RESULTS: Alpha tocopherol levels were significantly lower in critically ill patients (p < 0.001) as compared to healthy control subjects and those in two other disease groups (DM, CML) in which reactive oxygen species are reported to be increased. Elderly patients and patients who stayed longer than 8 days had lower plasma concentration of vitamin E. CONCLUSION: These findings indicate that antioxidant defence could be considerably compromised in these very sick patients and vitamin E supplementation may be beneficial in increasing their antioxidant reserve.