Journal/Magazine Articles
Permanent URI for this collectionhttp://repository.kln.ac.lk/handle/123456789/13
This collection contains original research articles, review articles and case reports published in local and international peer reviewed journals by the staff members of the Faculty of Medicine
Browse
16 results
Search Results
Item Composite carotid intima-media thickness as a risk predictor of coronary heart disease in a selected population in Sri Lanka(Public Library of Science,, 2022) Abeysuriya, V.; Wijesinha, N.A.I.; Priyadharshan, P.P.; Chandrasena, L.G.; Wickremasinghe, A.R.Background: Segment-specific variations of carotid intima-media thickness (CIMT) have not been assessed in South Asian populations. The purpose of this study was to determine if segment-specific CIMTs or a composite-CIMT score is a better risk predictor of coronary heart disease in South Asian populations. Methods: A comparative prospective study was conducted from November 2019 to October 2020 in a hospital in Colombo, Sri Lanka. Based on pre-defined inclusion and exclusion criteria, cases (having a diagnosis of Coronary Heart Disease (CHD), n = 338) and controls (non-CHD group, n = 356) were recruited. Ultrasound examination of the common carotid (CCA), the carotid bulb (CB) and the internal carotid segments (ICA) of the carotid vessels was conducted by a radiologist, and CIMTs were measured. A composite-CIMT score defined as the average value of all six segments of the left and right sides was derived. Results: 694 participants were enrolled (male n = 399, 57.5%). The mean (±SD) age of the study sample was 60.2 (±9.86) years. There were variations in segment-specific values between the left and right vessels. The mean composite-CIMT value of the CHD group was significantly higher than that of the non-CHD group. A composite-CIMT score of 0.758 had a sensitivity of 98.4% and a specificity of 64.6% in distinguishing CHD from non-CHD groups (Area under the curve (AUC): 0.926). Conclusions: Carotid artery segment-specific CIMT variations were present in this population. The composite CIMT score is better than segment-specific CIMTs in predicting CHD and may be used to predict CHD in this population.Item Serum cystatin C as a marker to identify patients with moderately impaired renal function(Association of Clinical Biochemists of India,, 2008) Peiris, H.; Chandrasena, L.G.; Lanerolle, R.D.ABSTRACT: The low molecular weight protein cystatin C produced by all nucleated cells and eliminated by glomerular filtration is of special benefit as a marker of renal function. A study was therefore undertaken to investigate whether serum cystatin C could be used as a marker to identify patients with moderately impaired renal function. A cross-sectional descriptive hospital based study was carried out and serum cystatin C was measured in fifty subjects aged 12 to 74 years with a 24 hr creatinine clearance estimation done at the same time. The gold standard creatinine clearance was used to compare the predicted glomerular filtration rate measured using serum cystatin C. Predicted glomerular filtration rate gave a sensitivity of 82% and specificity of 68% with a diagnostic cut-off value of 1.25mg/L cystatin C for identification of patients with moderately impaired renal function with a single random blood sample. AUTHOR KEYWORDS: Creatinine; Cystatin C; Glomerular filtration rate; Moderately impaired renal functionItem Outcome of patients with ST segment elevation myocardial infarction (STEMI) following percutaneous transluminal coronary angioplasty: a retrospective study(Sri Lanka Medical Association, 2014) Abeysuriya, V.; Chandrasena, L.G.; Kasturiratne, A.; Hettiarachchi, V.S.; Wickremasinghe, A.R.OBJECTIVES: To study the characteristics and long term outcome of patients who had segment elevation myocardial infarction (STEMI) and treated with PTCA in a fee levying hospital in Sri Lanka. METHODS: A retrospective study was conducted among patients diagnosed with STEMI and treated with PTCA in a fee levying private hospital in Colombo from 1st January 2009 to 1st November 2012. Details of patients were obtained from medical records and the survival status, cause of death and date of death where relevant, were obtained from records, patients or close relatives. RESULTS: 197 patients (153 men; 77.7%) were included. More than 50% had a history of diabetes, dyslipidaemia or hypertension. The three year survival was 82.7% (95% CI: 77.9%-90.5%). Based on the Cox's Proportional Hazards model, site of arterial occlusion (proximal vs distal segment of left anterior descending artery [LAD] was significantly associated with mortality due to all causes [HR 10.98; 95% CI: 1.09-110.20]. Low ejection fraction, not on regular medication and delay of more than 3 hours between onset to door time were associated with death due to cardiovascular causes in patients whose right coronary artery or left circumflex artery was the culprit artery. CONCLUSIONS: The three year survival of patients with STEMI and who had PTCA was 83%. Patients with proximal LAD occlusion were 11 times more likely to die within 3 years of PTCA as compared to those who had a distal LAD occlusion.Item Hemoglobin variants in patients with type-2 diabetes mellitus(SEAMEO Regional Tropical Medicine and Public Health Project, 2010) Chandrasena, L.G.; Peiris, H.; Williams, S.; Siribaddana, S.H.Measurement of HbA1c levels in diabetic patients is an established procedure for evaluating long-term control of diabetes. Despite its usefulness, conditions that effect hemoglobin concentration, such as hemoglobinopathies give rise to inappropriate HbA1c values. Since information about hemoglobinopathies in the diabetic population in Sri Lanka is limited, a prospective cross-sectional study was carried out among 2,695 diabetic subjects attending the diabetic clinic at Nawaloka Hospital, Sri Lanka. Hemoglobin type and HbA1c were measured by the HPLC method. The results reveal among 2,695 diabetic subjects, 53 (2%) had abnormal hemoglobin types (HbF and HbS). HbA1c concentrations in diabetic patients without Hb abnormalities show a higher correlation with fasting blood glucose than those with hemoglobin abnormalities. This study emphasizes that patients with inappropriate HbA1c values should be investigated for hemoglobinopathies.Item Biochemical changes associated withnreperfusion after off-pump and on-pump coronary artery bypass graft surgery(Institute for Clinical Science., 2009) Chandrasena, L.G.; Peiris, H.; Waikar, H.D.A prospective study was performed to monitor the postoperative changes in biochemical markers associated with reperfusion injury following (i) cardiopulmonary bypass (CPB) with aortic cross-clamping and cardioplagia (CABG); (ii) CPB with a tissue stabilizing device (SUP.CPB); or (iii) surgery on beating heart (off-pump CABG or OPCABG). Of the 48 patients, 16 were subjected to CABG, 16 to SUP.CPB, and 16 to OPCABG. Arterial and venous blood samples drawn 10 min preoperatively and 0.2, 4, 24, and 48 hr after surgery were assayed for plasma lactate, total calcium, and ionized calcium and erythrocyte glutathione peroxidase (GPX) and superoxide dismutase (SOD). Results revealed that ionized calcium, SOD, and GPX levels of all patients increased at 4 hr following surgery but returned to baseline levels at 24 or 48 hr after surgery. Increased postoperative GPX levels reflect a cellular defense mechanism against oxidative damage during reperfusion, while lactate levels during reperfusion reflect delayed recovery of aerobic myocardial metabolism. The postoperative release of lactate, GPX, and SOD in patients undergoing the CABG (on-pump) technique was significantly higher compared to those subjected to OPCABG or SUP.CPB. There were no significant differences in postoperative patterns of release of biomarkers in patients with OPCABG vs SUP.CPB, suggesting that these surgical techniques are equally acceptableItem Changes in erythrocyte glucose-6-phosphate dehydrogenase (G6PD) and reduced glutathione (GSH) activities in the development of senile and diabetic cataracts(SEAMEO Regional Tropical Medicine and Public Health Project, 2008) Chandrasena, L.G.; de Silva, L.D.R.; de Silva, K.I.; Dissanayaka, P.; Peiris, H.Oxidative and osmotic stress have been implicated in the pathogenesis of cataracts. Reactive oxygen intermediates (ROI) mediate peroxidation of membrane lipids and cause irreversible damage to lens proteins. The purpose of this study was to assess the changes in erythrocyte glucose- 6-phosphate dehydrogenase enzyme (G6PD) and reduced glutathione (GSH) levels in the development of senile and diabetic cataracts. The activity of erythrocyte G6PD and the concentration of GSH were measured to assess changes in oxidation-reduction status. The oxidation-reduction status of 26 non-diabetic non-cataract (control) subjects were compared with 24 diabetic non-cataract, 30 diabetic cataract and 28 non-diabetic cataract subjects. The results revealed that the GSH and G6PD levels of the subjects with senile cataracts were significantly lower than the subjects without cataracts. The present study reveals the risk of developing senile cataracts is associated with decreased levels of erythrocyte G6PD and GSH. In the formation of diabetic cataracts an adequate supply of NADPH (G6PD activity) is essential to produce osmotically active sorbitol in the lensItem Fifty years after Watson and Crick(University of Sri Jayewardenepura, 2007) Chandrasena, L.G.; Peiris, H.; Welihinda, J.AbstractItem Erythrocyte antioxidant enzymes in patients with cataract(Institute for Clinical Science., 2006) Chandrasena, L.G.; Chackrewarthy, S.; Perera, P.T.; de Silva, D.The pathogenesis of cataract has been found to be influenced by a number of factors including oxidative stress. Catalase, glutathione peroxidase (GPX), and superoxide dismutase (SOD) are some of the antioxidant enzymes that protect the body from oxidative damage. The present study investigates the activities of erythrocyte catalase, GPX, and SOD with respect to senile cataract (non-diabetic cataract) and osmotic cataract (diabetic cataract) in a Sri Lankan population. One hundred and two non-diabetic subjects (50 with cataract and 52 non-cataract) and 106 diabetic subjects (56 with cataract and 50 non-cataract) were recruited into the study. Erythrocyte catalase, GPX, and SOD activities were assayed and the data were analysed by t-test (p <0.05 for significance). In the non-diabetic group, significantly low levels of catalase, GPX, and SOD activities were associated with cataract when compared with non-cataract. No significant changes in catalase, GPX, and SOD activities were observed in the diabetic group between cataract and non-cataract. Senile cataract (non-diabetic cataract) was associated with significantly low levels of erythrocyte catalase, GPX, and SOD when compared with osmotic cataract (diabetic cataract). Positive correlations were observed between catalase and SOD (r = 0.75), catalase and GPX (r = 0.63), and SOD and GPX (r = 0.59) in subjects with senile cataracts. Our results indicate that erythrocyte antioxidant enzyme levels are decreased in senile cataract as opposed to osmotic cataract. Assays of these erythrocyte enzyme activities could provide a marker to identify individuals predisposed to senile cataract.Item Laboratory statistics in Clinical Decision marking Sri Lanka(The Kandy Society of Medicine, 2005) Chandrasena, L.G.; Peiris, H.; Sivayogan, S.No Abstract Available.Item Red blood cell antioxidant levels in Wuchereria bancrofti infections(Academic Press, 2002) Premaratna, R.; Chandrasena, T.G.A.N.; Abeyewickreme, W.; Chandrasena, L.G.; Senerath, S.; de Silva, N.R.; de Silva, H.J.The elimination of microfilariae of Wuchereria bancrofti is probably mediated by free radicals. Red cell catalase (C), glutathione peroxidase (GPX), and superoxide dismutase (SOD) activity levels were measured as an indirect method of assessing blood oxidant status in 29 asymptomatic microfilaraemics, 29 "endemic normals", and 29 controls living in a non-endemic area. Changes in the activity of these enzymes were also compared over a one month period in 22 asymptomatic microfilaraemics randomised to receive either single dose or 14 day treatment with diethyl carbamazine citrate (DEC). Red cell GPX activity levels were significantly higher in "endemic normals" when compared to mf positive cases and non-endemic controls. An early and significant increase in GPX activity (on days 3, 7 and 14 compared to pretreatment levels, p<0.01) was observed after DEC in both treatment groups. Increases in the activity of catalase and SOD became significant only on days 14 and 30 respectively. The percentage reduction in microfilaraemia correlated significantly with the percentage increase in GPX activity levels (R(2)=0.58, p=0.6 x 10(-5)). Our results may suggest a role for GPX related oxidant species in the elimination of microfilariae.