Platelet nitric oxide signaling system in patients with coronary artery disease.

BACKGROUND: Coronary artery disease (CAD) is the leading cause of death worldwide, and the major cause of hospital admissions in the Western countries. The pathogenesis of CAD is closely related to nitric oxide release and formation. The purpose of this study was to investigate the status of platelets nitric oxide in patients with coronary artery disease. METHODS: We measured platelets aggregation, cGMP, NO (nitrite/nitrate level), NO synthase activity, plasma NO, and ionized Ca(2+) in 40 healthy volunteers and 120 patients with myocardial infarction, unstable and stable angina, with 40 subjects in each group. The subjects' age mean range was from 40-51 years. RESULTS: Platelets aggregation, NO, cGMP, NO synthase activity, plasma NO and ionized Ca(2+) have increased significantly (P <0.001) across the patients groups compared to controls. Platelets NO synthase activity (mean ± SD / U / 10(9) platelets) in healthy controls, MI, unstable angina and stable angina patients were 1.19 ± 0.56, 1.21 ± 0.64, 1.64 ± 0.98 and 1.57 ± 0.81 respectively. The cGMP (mean ± SD / pmole / 10(9) platelets) levels were 0.95 ± 0.41, 1.53 ± 0.64, 3.18 ± 0.77, and 5.12 ± 1.5 respectively. CONCLUSIONS: The present study demonstrated that platelets aggregation, NO, cGMP, NO synthase activity, plasma NO, and ionized Ca(2+) profoundly increased in CAD. The increases in NO-cGMP components may have resulted as a compensatory response to ameliorate platelet activity and Ca(2+) levels in CAD patients.

Application of sigma metrics for the assessment of quality assurance in clinical biochemistry laboratory in India: a pilot study.

Ensuring quality of laboratory services is the need of the hour in the field of health care. Keeping in mind the revolution ushered by six sigma concept in corporate world, health care sector may reap the benefits of the same. Six sigma provides a general methodology to describe performance on sigma scale. We aimed to gauge our laboratory performance by sigma metrics. Internal quality control (QC) data was analyzed retrospectively over a period of 6 months from July 2009 to December 2009. Laboratory mean, standard deviation and coefficient of variation were calculated for all the parameters. Sigma was calculated for both the levels of internal QC. Satisfactory sigma values (>6) were elicited for creatinine, triglycerides, SGOT, CPK-Total and Amylase. Blood urea performed poorly on the sigma scale with sigma <3. The findings of our exercise emphasize the need for detailed evaluation and adoption of ameliorative measures in order to effectuate six sigma standards for all the analytical processes.

Platelets oxidative stress in Indian patients with ischemic heart disease.

BACKGROUND: Oxidative stress has been implicated in the development of atherosclerosis and vascular tissue injury. Both platelet activation and lipid peroxidation are known to play major role in ischemic heart disease. The purpose of this study was to investigate the status of platelets oxidative stress in Indian patients with ischemic heart disease. METHODS: We measured platelets aggregation, malonyldialdehyde (MDA), plasma-ionized Ca2+, and antioxidant enzymes, i.e., glutathione peroxidase and superoxide dismutase in healthy volunteers and patients with myocardial infarction, unstable and stable angina 40 subjects each. RESULTS: Platelets aggregation, MDA, and plasma-ionized Ca(2+) have increased significantly across the patients groups compared with controls, this increase was accompanied by an overall decrease in the antioxidant enzymes activity; except for the slight increases in the glutathione peroxidase levels among the myocardial infarction patients. CONCLUSIONS: The current results suggest that platelet lipid peroxidation as marked by increased MDA level is augmented in ischemic heart diseases. The increased oxidative stress seen in these patients was accompanied by platelet activation and impaired antioxidant enzymes activity.

Evaluation of errors in a clinical laboratory: a one-year experience.

BACKGROUND: Efficient laboratory service is the cornerstone of modern health care systems. Scientific innovations have contributed to substantial improvements in the field of laboratory science, but errors still prevail. These errors are classified as preanalytical, analytical and postanalytical, depending upon the time of presentation. METHODS: The data for 67,438 routine venous blood specimens were scrutinized, and errors were documented over the period of 1 year in the clinical biochemistry laboratory of Govind Ballabh Pant Hospital in Delhi, India. RESULTS: Preanalytical errors were most common, with a frequency of 77.1% followed by postanalytical 15% and analytical 7.9%, respectively. CONCLUSIONS: Our study illustrates the importance of proper venipuncture procedures, analytical expertise and correct transcription of numerical data for precise and accurate reporting of results to clinicians. There is an urgent need for close inter-departmental cooperation to meet the goal of ensuring patient well being.

Apo-B/apo-AI ratio: a better discriminator of coronary artery disease risk than other conventional lipid ratios in Indian patients with acute myocardial infarction.

BACKGROUND: Coronary artery disease (CAD) is a leading cause of morbidity and mortality in the developed world and is rapidly assuming epidemic proportions in developing countries including India. This has led to extensive research to determine the risk factors unique to this group which may predispose to the elevated risk of this disease. Important amongst them are lipoproteins, homocysteine, lipoprotein (a), pro-inflammatory cytokines etc. The following study was undertaken to evaluate the role of the apolipoprotein-B100 (apo-B)/apolipoprotein-AI (apo-AI) ratio as a predictor of CAD risk in the atherosclerosis-prone Indian population, as compared to other conventional lipid ratios. MATERIAL AND METHODS: The study group comprised 100 clinically assessed patients with acute myocardial infarction (AMI) diagnosed on electrocardiographic and biochemical criteria and 100 age-matched healthy control subjects. Apo-B and apo-AI levels were estimated by the immunoturbidimetric method, using kits from Randox, UK. Lipid profile was determined using standard enzymatic methods. The exponential regression coefficient beta was calculated for total cholesterol/high-density lipoprotein cholesterol (TC/HDL), TC-HDL/HDL, low-density lipoprotein ( LDL) cholesterol/HDL and apo-B/apo-AI ratios. RESULTS: The TC/HDL ratio was 5.15 +/- 1.7 and 3.45 +/- 0.87 in patients with AMI and control subjects, respectively (P< 0.001). The TC-HDL/HDL ratio was 4.61 +/- 2.6 and 2.22 +/- 1.14 in the patients with AMI and the control subjects (P <0.001). The LDL/HDL ratio was 3.32 +/- 1.5 in the AMI patients and 1.84 +/- 0.78 in the control subjects (P < 0.001); whilst the apo-B/apo-AI ratio in the patients with AMI was 0.96 +/- 0.30 and 0.71 +/- 0.20 in the control subjects (P <0.001). The exponential value of the regression coefficient beta (Exp [beta]) for apo-B/apo-AI ratio was 111.9, as compared to 4.4 for the LDL/HDL ratio, 3.5 for the TC/HDL ratio and 2.2 for the TC-HDL/HDL ratio, though all the lipid ratios were significantly higher in cases than in control subjects. CONCLUSION: Our findings suggest that the apo-B/apo-AI ratio is a better discriminator of CAD risk in the atherosclerosis-prone Indian population, than any of the conventional lipid ratios. The reduction of value of the apo-B/apo-AI ratio may drastically decrease the risk for CAD. Hence, the apo-B/apo-AI ratio may be suggested as an alternative to other lipid ratios fo risk assessment in patients with CAD.

A prospective, partially randomized study of pregnancy outcomes and hematologic responses to oral and intramuscular iron treatment in moderately anemic pregnant women.

BACKGROUND: Daily oral iron supplementation during pregnancy fails to reduce the prevalence of anemia. However, 2 or 3 intramuscular doses of iron given at monthly intervals were recently found to be effective. OBJECTIVE: We compared the safety and efficacy in treating pregnancy anemia of 3 intramuscular doses of iron given at monthly intervals with those of daily oral iron supplementation. DESIGN: In a prospective, partially randomized study, 148 pregnant women received daily oral doses of 100 mg elemental Fe and 500 micro g folic acid, and 106 pregnant women received 3 intramuscular doses of 250 mg elemental Fe as iron dextran at 1-mo intervals and oral doses of 5 mg folic acid twice weekly. One hundred women in each group completed the study. Changes in hemoglobin, iron indicators, pregnancy outcomes, and birth weight were compared between the 2 groups. RESULTS: Hemoglobin and iron indicators improved significantly with both treatments. The increase in serum ferritin concentration after parenteral iron treatment was significantly higher than that after oral iron treatment. No significant differences between the 2 groups in pregnancy outcomes and birth weight were observed. Systemic side effects were more common in the parenteral iron group, whereas gastrointestinal side effects were more common in the oral iron group. CONCLUSIONS: The intramuscular administration of 3 doses of 250 mg Fe at monthly intervals appears to have good compliance and efficacy and may be used in women who cannot tolerate oral administration of iron. However, intramuscular administration of iron is appropriate only in hospital settings well equipped to treat anaphylactic crises.

Etiology and clinical predictors of intractable epilepsy.

To determine the etiology and clinical predictors of intractable epilepsy, a case-control study comprising 50 patients and 50 control subjects was performed. Patients included children who had more than one seizure per month over at least 6 months. Control subjects included children with epilepsy who had been seizure-free for more than 6 months. Patients were evaluated with special reference to birth history and development. Clinical examination and neurodevelopmental assessment were performed in all the patients. Drug monitoring was performed to exclude pseudointractability. Epilepsy in the study group was caused by perinatal problems (48%) and sequelae of central nervous system infection (24%) and was idiopathic in 20%. In the control group, epilepsy was idiopathic in 72%, a result of calcified granuloma in 22%, and perinatal problems comprised 6% of the subjects. On univariate analysis, strong association was evident between intractable epilepsy and several factors, including age at onset of seizure, remote symptomatic epilepsy, initial seizure type, history of neonatal seizure, high initial seizure frequency, microcephaly, and neurologic impairment. On multivariate analysis, neurologic impairment (odds ratio [OR] 12.25; 95% confidence interval [CI] 3.58-41.89), age at onset of seizure less than 1 year (OR 11.70; 95% CI 2.95-46.43), myoclonic seizure/infantile spasm (OR 10.36; 95% CI 2.39-44.93), and remote symptomatic epilepsy (OR 2.9; 95% CI 1.13-7.43), were independent predictors of intractability.