http://dr.lib.sjp.ac.lk/handle/123456789/761 2026-04-23T10:23:44Z http://dr.lib.sjp.ac.lk/handle/123456789/1028 The Impact of the Change in the Medium of Instruction on the Performance of Undergraduates in University Examinations Hewapathirana, T.K. The objective of the present study is to determine the impact of the medium of instruction on the performance of undergraduate students in university examinations. The results of six Biological Science course units in Zoology and Microbiology and six Physical Science course units in Physics and Statistics & Computer Science of two groups of undergraduates who entered the Faculty of Science of the University of Kelaniya in years 2000 and 200 I were considered in the analysis. Those who have entered in 2000 followed all course units in Zoology, Physics and Statistics & Computer Science in Sinhala medium and Microbiology in English medium. Those who entered in 2001 followed all Microbiology course units and those in other subjects from 2nd semester onwards in English medium. Analysis of results using the Kolmogrov - Smimov tests revealed that the medium of instruction has no significant effect on the performance of undergraduates in university examinations. 2002-01-01T00:00:00Z http://dr.lib.sjp.ac.lk/handle/123456789/1027 Studies on the Effect of the Heat on the Neurotoxic Factor of Palmyrah Flour Keerthi, A.A.P.; Hoevan, R. Van Der; Nikawaka, J.K.; Jansz, E.R. Previous reports state that the flour of palmyrah (Borassus flabellfer L), called odiyal, on heating at 80·C for 45 minutes caused removal of hepatotoxic and neurotoxic factors effectively, and that odiyal flour originated from Kalpitiya was more toxic to Wistar rats than odiyal flour from Jaffna. These studies show that the heating can cause loss of volatiles but there is apparently no toxic factor in the volatiles. GC-MS analysis shows that the decanoic acid (capric acid), undecanoic acid (hendecanoic acid), 2- butenedioic acid and their esters as main volatile compounds. No amines were present. Heating of Kalpitiya odiyal flour shows a decline in ninhydrin positives prominently those from the MPLC fractions from ethyl acetate to methanol. Kalpitiya odiyal flour unheat-treated had higher total amine concentration than that of Jaffna odiyal. Circumstancial evidence shows that the increased toxicity of Kalpitiya odiyal flour compared to Jaffna odiyal flour may be due to the kottakilangu (dried shoot of palmyra h) milling temperature (58- 60°C) for Kalpitiya flour and >80°C for Jaffna flour. 2002-01-01T00:00:00Z http://dr.lib.sjp.ac.lk/handle/123456789/1026 Studies on Amines of Hurulla (Amblygaster sirm) Do They Cause Allergic Reactions of Hurulla? Perera, P. Shiromi; Jansz, E.R.; Peiris, H. Past studies stated that consumption ofhurulla (Amblygaster sirm) gave an adverse reaction to tuberculosis patients treated with isoniazid drugs and that the cause may be tyramine. In order to test this hypothesis fresh hurulla samples were tested for histamine and tyramine with and without storage at room temperature using TLC and enzymatic methods. Only traces of tyramine (RfO.88) were found in only 5% of the samples ofhurulla even in the presence of exogenous tyrosine. However, histamine (Rf 0.63) was detected and it was low, 0.34 mg/g of fish. Many other free amino acids were detected on keeping the fish at room temperature. The bacteria producing these amines were isolated from the fish and cultured in a liquid medium. TLC was carried out from these bacterial supernatants to detect histamine. Histamine spots were then quantified by (I) ninhydrin reaction using a spectrophotometer at 570nm or densitometer. (II) Using an ELISA technique. (III) Histaminase assay. All forty-four bacterial colonies isolated were tested for histamine production from histidine. Eleven colonies showed> 0.8mg/m!. However studies with this culture in the log phase of the growth showed that the bacteria produced maximum histamine at 24 hours. However histamine content declined thereafter and was not detected in a 48 h culture. Adjusting pH to 1to solubilize histamine complex increased histamine levels. Addition of EDTA (0.005mg.ml-') increased histamine content with the age of supernatant indicating that chelation could prevent the breakdown of histamine decarboxylase. There was no evidence of breakdown of histamine or tyramine. Studies show that tyramine is not the cause for adverse reactions with isoniazid drugs. Although the histamine content is low, it may contribute to allergic reactions. 2002-01-01T00:00:00Z http://dr.lib.sjp.ac.lk/handle/123456789/1025 Neurotoxic Effect Traditional Cooking of Wistar Rats Fed with Recipies of Palmyrah Flour Sumudunie, K.A.V.; Jayasekara, S.; Jansz, E.R.; Wickramasinghe, S.M.D.N. Palmyrah (Borassus flabellifer L.) shoot has been proved to give a neurotoxic effect. This study using male Wistar rats shows that the time for advent of neurotoxic symptoms is affected by the location from which the seed shoot (which gives rise to this flour) is collected. Studies show that the advent of neurotoxic symptoms can be delayed but not eliminated by washing and steaming the flour and using boiled shoots to prepare traditional foods. The neurotoxic effect was always accompanied by a significant elevation of serum aspartate aminotransferase (AST) but not alanine aminotransferase (ALT). Showing that there is no evidence, even sub-clinically, for the hepatotoxic effect previously reported. The findings are alarming as these traditional foods are widely consumed in North-east Sri Lanka. The only mitigating factor is the possibility of the neurotoxic effect being species dependent. 2002-01-01T00:00:00Z