Deepaka Weerasekera
University of Sri Jayewardenepura
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Featured researches published by Deepaka Weerasekera.
Gastroenterology Research and Practice | 2017
Piyumali Sandareka Arachchi; Neluka Fernando; Manjula Weerasekera; Bimalka Senevirathna; Deepaka Weerasekera; Chinthika Gunasekara
Background The pro- and anti-inflammatory cytokines play an important role in the immune response against H. pylori infection. The proinflammatory cytokines of Th17 cells have been suggested to play a major role in H. pylori infection and resulting gastric inflammation. Objective The objective of this study was to compare the expression of selected inflammatory cytokines (IL-10, IL-17, IL-21, IL-23, and TNF-α) in H. pylori-infected patients and healthy controls and to understand their association with H. pylori infection and disease severity. Results The expression levels of IL-17 and IL-23 were significantly higher in H. pylori-infected patients. The expression of IL-21 was also higher in H. pylori-positive patients but there was no significant association with infection. IL-17 expression showed a significant increase with the severity of chronic gastritis. Conclusion The proinflammatory cytokine, IL-17, shows a significant association with H. pylori infection and disease severity in a Sri Lankan dyspeptic patient population.
Microbiology and Immunology | 2018
Piyumali Sandareka Arachchi; Manjula Weerasekera; Bimalka Senevirathna; Deepaka Weerasekera; Neluka Fernando; Chinthika Gunasekara
Single nucleotide polymorphisms present on the promoter sequence of the TNF‐α gene may affect production of TNF‐α, a pro‐inflammatory cytokine, during immune responses. The presence of TNF‐α polymorphisms is also reportedly associated with more severe manifestations of Helicobacter pylori infection. However, the frequency of TNF‐α polymorphisms and the associated disease severity vary between different patient groups. In this study, gastric biopsies and blood specimens were collected from 138 patients with dyspepsia undergoing routine upper gastrointestinal endoscopy. Our institutions Ethics Review Committee approved the study and written informed consent was obtained from all participants. The presence of H. pylori was confirmed histologically in all patients. The frequency of TNF‐α polymorphisms in the study cohort was investigated using PCR–restriction fragment length polymorphism and expression of serum TNF‐α quantitated using a commercial ELISA assay. The proportions of selected TNF‐α polymorphisms (TNF‐α ‐238, ‐308 and ‐863) were similar in H. pylori‐positive and ‐negative patients. Homozygous mutations of TNF‐α polymorphisms were rarely detected in the study group. There was a significant difference in TNF‐α concentrations between patients with mild chronic gastritis and TNF‐α ‐308 GG genotype and patients with moderate to severe chronic gastritis (P = 0.008). It was not possible to identify an association between these genotypes and disease severity because of the low frequency of heterozygous and homozygous mutated genes in Sri Lankan patients with dyspepsia.
BMC Research Notes | 2018
Piyumali Sandareka Arachchi; Manjula Weerasekera; Bimalka Seneviratne; Deepaka Weerasekera; Neluka Fernando; Chinthika Gunasekara
ObjectiveThe study aimed to compare the usefulness of two staining methods for imprint cytology for diagnosis of Helicobacter pylori infection. Gastric biopsy specimens (from dyspeptic patients attending routine upper gastrointestinal endoscopy) were placed on glass slides to obtain imprints. The imprints were stained with Toluidine blue and Giemsa stains separately and observed under ×400 magnification using a light microscope. Imprinted biopsies were sectioned and stained with H & E stain and Giemsa stain for histological analysis. Diagnosis of H. pylori infection in both imprint and histological sections were confirmed by a consultant pathologist. The sensitivity, specificity, positive predictive value and negative predictive value of each stain were calculated and benchmarked against histological diagnosis.ResultsOf the 55 dyspeptic patients enrolled in the study, 5 were positive for H. pylori by Toluidine blue stain and 4 by Giemsa stain. The sensitivity of Toluidine blue stain (57.1%) was higher than Giemsa stain (42.9%) while the specificity of both stains was equal (97.9%). Giemsa stain gave a better discrimination for identification of H. pylori bacteria among the mucosal background. Imprint cytology is a rapid, simple and cost effective diagnosis method that can supplement histological diagnosis.
International Journal of Enteric Pathogens | 2016
Piyumali Sandareka Arachchi; Chinthika Gunasekara; Manjula Weerasekera; Nushka Lahiri Ubhayawardana; Deepaka Weerasekera; Kamani Samarasinghe; Bimalka Seneviratne; Neluka Fernando
Background: Helicobacter pylori has been identified as a group I carcinogenic bacteria that infect the gastric mucosa leading to gastritis, peptic ulcer disease, lymphoma and gastric cancer. Pathogenesis of H. pylori depends on the virulence of the strain, host immune response and modulating factors like smoking and diet. Objective: This study aimed to assess the association of selected HLA (Human Leukocyte Antigen) alleles; HLA-DQA1*0102, HLA-DQA1*0103 and HLA-DQB1*0301, with the presence of H. pylori infection and disease severity among dyspeptic patients. Methods: Gastric tissue samples from 100 dyspeptic patients, who underwent upper gastrointestinal endoscopy at a tertiary care hospital, were collected. Presence of HLA alleles was confirmed using Polymerase Chain Reaction (PCR). H. pylori infection was determined using PCR and Histology. The histological interpretation was done according to the ‘Sydney classification’. Statistical analysis was done with the Statistical Package of Social Sciences (SPSS) (version 22; SPSS, Inc., Chicago, Illinois, USA). Results: Respective percentages of HLA-DQA1*0102, HLA-DQA1*0103 and HLA-DQB1*0301 were 39%, 31% and 20%. Of the 25 samples positive for H. pylori infection respectively 56% (14/25), 36% (9/25) and 12% (3/25) were positive for HLA-DQA1*0102, HLA-DQA1*0103 and HLA-DQB1*0301 alleles. Considering the association with H. pylori infection, only HLA-DQA1*0102 showed significant association (p=0.044). No significant association was found between the HLA alleles and the histological severity among the H. pylori infected patients. Conclusion: In conclusion, HLA-DQA1*0102 allele has a significant association with H. pylori infection while HLA-DQA1*0103 and HLA-DQB1*0301 shows no significant association in a Sri Lankan dyspeptic patient population.
World Journal of Gastroenterology | 2005
Rachel O’Mahony; Huda Al-Khtheeri; Deepaka Weerasekera; Neluka Fernando; Dino Vaira; John Holton; Christelle Basset
Journal of The National Science Foundation of Sri Lanka | 2008
Deepaka Weerasekera; Neluka Fernando; Lbae Bogahawatta; R Rajapakse-Mallikahewa; Dj Naulla
International Journal of Enteric Pathogens | 2015
D.L. Nushka L. Ubhayawardana; Manjula Weerasekera; Deepaka Weerasekera; T.D. Chinthika P. Gunasekera; S.S. Neluka Fernando
World Academy of Science, Engineering and Technology, International Journal of Medical and Health Sciences | 2018
Ayomi Dilhari; Chinthika Gunasekara; Neluka Fernando; Deepaka Weerasekera; Uditha Bulugahapitiya; Sujatha Pathirage; Chris H. Sissons; Andrew J. McBain; Manjula Weerasekera
Proceedings of Annual Scientific Sessions of Faculty of Medical Sciences | 2017
K.A.A. Dilhari; T.D.C.P. Gunasekera; Ssn Fernando; Deepaka Weerasekera; Uditha Bulugahapitiya; S Pathirage; Chris H. Sissons; Andrew J. McBain; Manjula Weerasekera
Proceedings of Annual Scientific Sessions of Faculty of Medical Sciences | 2015
D.L.N.L. Ubhayawardana; Deepaka Weerasekera; Ssn Fernando; A. Kishokumar; I.W.M.P. Wanigasooriya; Manjula Weerasekera; T.D.C.P. Gunasekera; K. Samarasinghe