Browsing by Author "Bandara, A."

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Application of nucleic acid technology (NAT) in the diagnosis of active viral replication in HBV and HCV infections and evidence for HBV surface antigen mutants
(Sri Lanka Association for the Advancement of Science, 2008) Manamperi, A.; Gunawardene, Y.I.N.S.; Hapuarachchi, C.; Bandara, A.; Wellawaththage, C.; Abeyewickreme, W.; de Silva, J.
Introduction: The community prevalence of Hepatitis B (HBV) and hepatitis C (HCV) infections, although considered low (< 1%) in Sri Lanka based on serological markers, pose a significant health threat to patients in high risk groups. The early diagnosis of active viral infection is crucial in such situations to prevent further transmission and to enable the clinicians to initiate successful therapeutic interventions. Objective: This study was carried out to investigate the usefulness of polymerase chain reaction (PCR) in the diagnosis of active viral replication in HBV and HCV infections. Methodology: All specimens from patients with serological evidence of hepatitis B (HBV surface antigen and/or antibodies for HBV core protein) or hepatitis C (antibodies for hepatitis C core protein-Anti-HCV) and referred to the Molecular Medicine Unit from May 2005 to May 2008 were analyzed by PCR and reverse-transcription PCR (RT-PCR) for HBV DNA (n=130) and HCV RNA (n=95) respectively. Results: Of the 130 patients tested, 57 (44%) were positive for HBV DNA. The positive group of patients included 10 renal transplant patients, 4 multiply transfused patients, 4 paediatric patients with lymphoma, and 1 patient with cirrhosis. Six HBV DNA positive patients had negative HBsAg serology profiles indicating the possibility of surface antigen mutant strains. The HBV DNA negative patients with positive serology profiles indicate sero-converted/ patients with resolved infections or false positive serology results. Of the 95 patients tested, 14 (15%) were positive for HCV RNA and included 3 paediatric patients with thalassaemia. HCV RNA negative, anti-HCV positive profiles reflect either false positive serology results (due to less specific antibody assays) or donors who have been exposed to HCV previously and subsequently resolved their infections. Conclusions: A major proportion of patients with serological markers for HBV have active viral infection whereas only relatively a minor proportion of patients with serological markers for HCV have active viral replication. We have also found the first possible evidence of hepatitis B surface antigen mutant strains. This underlines the importance of the nucleic acid based technology in the diagnosis and assessment of infection with or suspected to have hepatitis B or C infections. We also emphasize the importance of introducing NAT for screening donors for HBV DNA and HCV RNA to substantially lower the risk of acquiring HBV/HCV infection from a transfusion.
Genetic Polymorphism in Pvmsp-3a. and Pvcs genes in Plasmodium vivax infections in Sri Lanka
(Sri Lanka College of Microbiologists, 2008) Manamperi, A.; Fernando, D.; Mahawithanage, S.; Wickremasinghe, R*.; Bandara, A.; Wellawatta, C.; Hapuarachchi, C.; Abeyewickreme, W.; Wickremasinghe, R.
INTRODUCTION: Plasmodim vivax malaria accounts for about 70% of all malaria infections in Sri Lanka. There is limited information on the genetic heterogeneity of P. vivax parasites in endemic areas of the country. OBJECTIVE: The objective of this study was to assess the potential of two P. vivax genes, Pvmsp-3v. and Pvcs. as genetic markers for their use in genotyping parasites collected from the field. METHOD: DNA was extracted from 12 Geimsa-stained P. vivax positive slides by phenol/chloroform method. A nested polymerase chain reaction (PCR) approach was adopted for both Pvmsp-3a and Pvcs genes. RFLP analysis ofPvmsp-la nested PCR products was carried out with Hha\ restriction enzyme. RESULTS AND DISCUSSION: Nested amplification of the marker genes resulted in 4 size variants for Pvcs (~ 600-750 bp) and 2 size variants for Pvmsp-3a (1.9 kb and 1.1 kb). Further, all PCR-RFLP products of Pvmsp-3a. Gene showed a major size polymorphism. Three samples showed evidence of infections with mixed genotypes and there was also evidence to identify a relapse infection. Analysis of these two genetic markers revealed 11 distinguishable variant types: 4 for Pvcs and 7 for Pvmsp-3a. CONCLUSIONS: The observed PCR and PCR-RFLP profiles of the Pvcs and Pvmsp-3& genes demonstrate that the P. vivax parasites in Sri Lanka were highly diverse despite the prevailing low transmission levels. It could be concluded that these two genes in combination could be considered suitable genetic markers to analyze P. vivax parasite dynamics in Sri Lanka.
Screening of hepatitis C (HCV) antibody reactive donors by RT-PCR in a sample population of blood bank donors in Sri Lanka
(Malaysian Society of Parasitology and Tropical Medicine, 2007) Manamperi, A.; Gunawardena, N.K.; Nugawela, P.; Bandara, A.; Wellawaththage, C.; Bindusara, R.M.; de Silva, H.J.; Abeyewickreme, W.
The practice of screening donors for HCV antibodies has substantially lowered the risk of acquiring HCV infection from a transfusion. However, detection of molecular markers in blood is the most reliable means of diagnosing active viral infection. Molecular studies on HCV antibody reactive donors have not been previously performed in Sri Lanka. The present study was carried out to investigate the RNA positive rates in a sample population of anti-HCV antibody reactive blood donors in Sri Lanka, with a view of determining whether RT-PCR testing for HCV RNA should be carried out at the initial donor screening level. Eighty nine (89) HCV antibody reactive donors were tested for the presence of HCV RNA by RT-PCR (sensitivity 200 copies/ml) during the period October 2005 to May 2006. The 89 serology positive donors were initially detected by a third generation ELISA by routine screening of an initial pool of 26,176 blood donors. Of the 89 Anti-HCV antibody positive donors (0.34% of the total donor pool), 6 (0.023% of the total donor pool, and 6.74 % of antibody positive individuals) were positive for HCV RNA. The prevalence of HCVRNA positivity was low in this cohort of Sri Lankan blood donors. This is in keeping with the low prevalence of HCV infection in the community. Routine individual HCV-RNA screening of donors does not seem cost-effective in our setting. The RNA negative, antibody positive profiles reflect either false positive serology results or donors who have been exposed to HCV previously and subsequently resolved their infections.
STR polymorphisms in Sri Lanka: evaluation of forensic utility in identification of individuals and parentage testing
(Sri Lanka Medical Association, 2009) Manamperi, A.; Hapuarachchi, C.; Gunawardene, N.S.; Bandara, A.; Dayanath, D.; Abeyewickreme, W.
OBJECTIVES: This preliminary study was carried out to determine the allele frequencies and forensic efficiency parameters for the short tandem repeat loci CSF1PO, TPOX, THO1, D16S539, D7S820, D13S317, vWA, FESFPS and F13B in a test sample population of Sri Lankans. DESIGN: Test samples were obtained from 305 non-related individuals originating from all 9 provinces of Sri Lanka. DNA was extracted from whole blood using chelex-100 and amplified by PCR using the GenePrint STR kit and silver stained. Final DNA profiles were analysed for forensic efficiency parameters and paternity indices using PowerStats version 12. Possible divergence from Hardy-Weinberg Equilibrium was tested using the chi-square test and exact test. RESULTS: All common alleles in the allelic ladders were found in the test sample studied. PIC values >0.5 for all 9 STR loci indicate this STR system to be informative and useful for identification purposes. The D13S317, vWA and D7S820 loci were found to be the most polymorphic markers of the system studied. CONCLUSIONS: No deviations from Hardy-Weinberg Equilibrium were found for any of the loci examined. The results indicate that the 9 STR loci system described here is suitable for estimating DNA profile frequencies in human identification and forensic and parentage testing for legal purposes among Sri Lankans.
A study on anxiety and depression among military personnel injured in the war
(Sri Lanka Medical Association, 2001) Ariyaratne, R.; Arulrajah, S.; Ariyananda, D.; Ariyaratne, J.; Athanayake, S.; Azhar, M.; Bandara, A.; Bandara, R.; Williams, S.S.; Kuruppuarachchi, K.A.L.A.
OBJECTIVES: To determine the proportion of army personnel with symptoms of anxiety and depression following injuries on the battlefield and to identify associated factors. DESIGN, SETTING AND METHODS: We administered a pretested closed and open ended questionnaire and a validated Sinhala translation of the Beck Depression and Beck Anxiety Inventory to 128 injured soldiers at the Military Hospital in Colombo between 9th and 11th of December 1999. We excluded soldiers with head injuries or impaired consciousness and those blind or deaf. RESULTS: In terms of the Beck Depression Inventory 35.15% had scores for severe depression, 15,62% for moderate depression and 28.1% for mild depression. In terms of the Beck Anxiety Inventory 7.81% has scores for severe anxiety, 5.46% for moderate anxiety and 36.7% for mild anxiety. There was a significant association between severity of depression and anxiety (Chi square for linear trend =21.8, p < 0.001). We also found a significant association between severity of depression and thoughts of deserting the army (Chi square for linear trend = 10.674, pO.OOl and severity of depression and problems at work or in the family (Chi square for linear trend = 4.373. p < 0.05). Among those who scored for severe depression there was a suicidal risk in 42.33%. CONCLUSIONS: We found that the majority of injured soldiers had symptoms of depression and nearly half had symptoms of anxiety, There was a significant association between severity of depression and thoughts of deserting the army and problems at work or in the family. The suicidal risk among depressed patients was high.
The use of the word “Seriously” in social network
(Department of English, University of Kelaniya, 2015) Alwis, S.; Bandara, A.; Mayakaduwe, C.; Salwatura, T.; Koralage, A.; Bandara, T.
Nowadays, many of the slangs have emerged from social network and they are used to state disbelief, doubts, as intensifiers and also as responses to someone stating the obvious. Word “seriously” is an adverb which uses to indicate the importance of an action. However, in today’s context there is a question “what is the present status of the word?” The aim of this research is to find answers for this question. According to the findings of the research, the word “seriously” is using as a positive exclamation in social network. The word “seriously” is using as a negative exclamation in social network. It has become a trend among young generation to change the real meaning of the word “seriously” and currently they are using this word as a slang exclamation too. Nevertheless the old generation is still using the word to convey the real meaning. According to the analysis of the findings final outcome is the word “seriously”, is more often used as an exclamation than as a general word. It is also used as both positive (grave, sincere, nothing humorous) and negative exclamation (disbelief). The word “seriously” is mostly used by the young generation as a slang exclamation but middle age people also use it to a certain extent.