Is direct method of low density lipoprotein cholesterol measurement appropriate for targeting lipid lowering therapy?

OBJECTIVES: The aim of this study was to compare the Friedewald Formula with direct homogeneous low density lipoprotein cholesterol (LDL-C) assay for the detection of LDL-C levels. METHODS: Fasting serum samples were obtained for lipid analysis from 1001 patients. Total cholesterol (TC) and triglyceride (TG) levels were measured with enzymatic methods and the measurements of high density lipoprotein cholesterol (HDL-C) and LDL-C levels were detected using direct methods. RESULTS: The mean levels of serum TC, TG, HDL-C and LDL-C were detected with in the reference range. The LDL-C estimated by the Friedewald formula was significantly correlated (P<0.01) with the direct method but there was a negative bias among them. CONCLUSION: Laboratories cannot use direct method as a substitute for Friedewald formula because direct method has not been standardized in large populations and increase cholesterol assay costs.

Early prediction of anthracycline induced cardiotoxicity.

AIM: The purpose of this study is to evaluate echocardiographically determined cardiac functions with serum levels of brain natriuretic peptide (BNP), cardiac troponin I (cTnI) and total antioxidant status (TAOS) in childhood leukemia treated with chemotherapeutics containing anthracyclines. METHODS: A study group of 29 patients who have been followed for acute lymphoblastic leukemia (ALL) and administered a treatment protocol containing chemotherapy of anthracyclines were included in the analysis. Levels of BNP, cTnI and TAOS were studied in serum samples of the patients. RESULTS: We demonstrated that as the drug dosage increased, systolic ejection fraction (EF) and shortening fraction (FS) values decreased (EF r2=0.2327, FS r2=0.251). On the other hand, increased dosage of anthracycline therapy was associated with significant raise in plasma BNP levels (r2=0.246) and significant decrease in serum TAOS levels (r2=0.317) without any change in serum cTnI levels. CONCLUSION: Our study suggest that serum TAOS and BNP levels may be useful as an early and sensitive indicator of anthracycline induced cardiotoxicity.

Reduced antioxidant potential & sensitivity to oxidation in plasma low density lipoprotein fraction in type 2 diabetes mellitus patients.

BACKGROUND & OBJECTIVES: The aim of this study was to investigate LDL oxidation in the ethiopathogenesis of diabetes mellitus. Diabetes mellitus a disease caused due to severe insulin dysfunction, is associated with lipid and protein metabolic disorders. METHODS: A total of 90 type 2 diabetes patients were grouped according to their glycoted haemoglobin (HbA1c) values as regulated (<5.7%), poorly regulated (5.7 - 7.7%) and unregulated (>7.7%). Further, a healthy control group of 37 individuals was included for comparison in terms of sensitivity of low density lipoprotein (LDL) to oxidation and measurements of antioxidant potential (AOP). A heparin - citrate precipitation method was used to obtain LDL from the serum samples of patients and control groups. The LDL fractions were exposed to oxidation with CuSO4 and sensitivity to oxidation was evaluated. Ten patients each from regulated and unregulated groups, and 10 healthy controls were examined for antioxidant potential. RESULTS: The sensitivity of LDL fraction to oxidation was significantly lower in all diabetic groups compared to the control group. AOP was significantly decreased in unregulated diabetic group compared to the control group. INTERPRETATION & CONCLUSION: We hypothesize that oxidant stress increases in diabetes mellitus and oxidant defense systems weaken during the chronic course of the illness. Due to decreased antioxidant potential, that probably shortens the LDL oxidation lag phase, the sensitivity to oxidation appears to be lower in diabetes mellitus patients.