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Item Sociocultural factors contributing to malnutrition(University of Peradeniya: UP(MED)., 1984) LIYANAG, CEMalnutrition in infants, young children, and pregnant and lactating mothers is a serious problem and an important cause of ill health and mortality in Sri Lanka. The problem of protein energy malnutrition that affects millions of children in the world is firmly rooted in the cultural pattern, dietary habits and the general soci.o-economic condition of the people. These are important factors to be considered in raising the nutritional status of the groups in the community.. The paucity of information on some aspects of these factors prompted me to under this study In this project the epidemiology of protein energy malnutrition :was studied. With emphasis on sociocultural factors contributing to the nutritional problems among pr~-school children in four estates in the Kandy Superintendent of Health Services (~HS) area. Estates in the Kandy SHS: area were selected for the prevalence of protein energy malnutrition (PEM) i8 hisrne!3t in the Kandy SHS area and also because , out of the three island wide population sectors (viz. urban, rural and estate) the highest prevalence of PEM is in the estate sector. Assessments were made of the nutritional status of the pre-school children anthropometrically and biochemically In addition the educational and ú work status of parents, weaning and infant feeding practices, dietary patterns of the children, food taboos, beliefs, prejudices, customs and avoidances during infancy, pregnancy and lactation, food purchasing and consumption ;pattern of the family, maternal nutritional status the level of their basic nutritional knowledge and demographic data (e.g. family site, number of pre-school children, birth rank) which were thought to be relevant to malnutrition were also studied. A questionnaire was used for the dietary survey Data thus obtained revealed the widespread prevalence of malnutrition among children the target population and allowed examination of the relationships between the various factors affecting the nutritional status of the children.Item A Study of the uterotonic and anti-implantation activities of some selected plant extracts and products(University of Peradeniya: UP(MED)., 1991) GOONASEKARA, MMSixty one plants reputed to have anti-fertility activity were tested on female Sprague-Dawley rats, in order to isolate active compounds with a potential for use in human fertility regulation. The experiments were carried out with crude plant extracts in the first instance. If any activity was present, the extracts were fractionated. Two bioassay methods were utilized in these investigations. The extracts were assessed for Possible abortifacient effects by an in vitro method of testing for uterotonic activity. In this method the isotonic contractions of the isolated uterine horn of the oestrogenised rat were observed in the presence of various plant extracts. A total of forty two extracts, one fraction and two pure compounds were tested in the in vitro system and thirty extracts gave Positive results. An in vivo method was utilized in order to determine any anti-implantation, early abortifacient and/or foetal resorption effects of these extracts. One hundred and thirty extracts as well as one hundred fractions and seven pure compounds were tested by the in vivo method. The rats were administered the extracts from day 1-10post- coitally and the anti- fertility effect was assessed on the sixteenth day at autopsy. Five plants, namely, calotropis gigantea calotropis procera, plumeria rubra, Juniperus sabina and Jatropha curcas were identified as highly promising leads from which anti-fertility compounds may be isolated. Since several plant extracts resulted in a loss of appetite ,the effect of a reduced feed intake on reproduction in laboratory animals was also investigated. The tests demonstrated the need to monitor the feed intake when using laboratory animals for anti fertility testsItem Studies on cutaneous leishmaniasis in Sri Lanka: clinical presentation diagnosis, molecular charcterisation and screening for possible reservoir hosts(University of Peradeniya: UP(MED)., 2005) Nawaratne, KMGSSKItem Immunological responses to ascaris lumbricoides linnaeus, 1758 in man and experimental animals(University of Peradeniya: UP(MED)., 2011-02-07) DE SILVA WIJESUNDERA, MKItem Mycotoxins in coconut based human and animal foodstuffs(University of Peradeniya: UP(MED)., 1975) SAMARAJEEWA, UAn attempt has been made in this study to determine the extent of the aflatoxic problem in Sri Lanka with special reference to coconut products with a view to suggesting preventive and regulatory measures for the control of contamination. The study of the extent of the aflatoxic problem was made by first establishing the most suitable method for the assay of aflatoxins in coconut products. Although several procedures have been described for the assay of aflatoxins in various agricultural products there was no established procedure for the assay of aflatoxins in coconut products. A method based on blending with a mixture of chloroform and water. originally devised for groundnuts, has been used by some workers for coconut products. However no data was available on the comparative suitability of this method as regards its extraction efficiency, interference on thin layer chromatographic estimations and convenience. Therefore the existing methods for the various products were restudied with coconuts to establish the best conditions for each method of extraction. The methods were then compared under optimum conditions. All procedures were found to bring about only partial extraction (about 70percent) of aflatoxins. The 70percent aqueous acetone blending procedure w1th lead acetate purification was found to be the most suitable on account of convenience and the purity of extracts which enabled titration without a preliminary column purification. Since a constant fraction of aflatoxin present in a given type of coconut product was extracted by a single homogenization by the aqueous acetone procedure, the application of a correction factor (to replace 2nd and 3rd homogenizations) is recommended, as a time and solvent saving measure~. Application of correction factors for the observed aflatoxin levels has not been described in the literature for assay of aflatoxins. As regards bioassay of extracts, the tadpole bioassay method established earlier for pure aflatoxins was found to be applicable to crude extracts of commercial samples preceded by a short column purification. A field survey was done for the year 1973 to study in detail the extent and origin of aflatoxin contamination in coconut products by examining copra, poonac and coconut oil samples from almost all oil processing mills in different districts during the periods January to April, May to August and September to December. About 50percent of the s~ples collected at random from the firld were found to contain aflatoxins above the maximum permissible level (0.03 ppm in foods for human consumption, suggested by WHO/FAO/UNICEF). The contamination was found to be due mostly to ignorance and negligence during curing and storage of copra. Education of the copra miller and worker, on the economic and toxicological consequences of contamination is of prime importance in the prevention of contamination. Reorganization of the present inspection network in the mills is suggested as a measure for effective control. The economic loss to the industry due to fungal contamination of copra during storage has been estimated earlier to be around 25percent and such control may therefore minimize these losses. Contaminated coconut oil should be diverted for chemical refining or split into glycerol and fatty acids. The contaminated copra should either be steam treated at high pressure or be rejected totally if the contamination is heavy. Investigation into an outbreak of deaths of young goats of an imported breed at Kottukachchiya (NWP) Government goat breeding centre was shown to be due to aflatoxins. The aflatoxins were detected in the feed samples and in the liver tissues and urine of diseased or dead animals. Strains of Aspergillus flavus were isolated from feed samples and were shown to be toxigenic. Identical clinicle features, postmortem appearances and histopathological lesions were produced by experimental feeding of the goats with artificially infected coconut. The factor that contributed to the toxicity of the industrial feed was found to be an ingredient 'polkudu' added in the preparation of the feed mixtures. As there were significant levels of aflatoxins in local coconut products which could cause toxic and trade problems it became necessary to investigate possible methods of prevention of contamination and detoxification of already contaminated samples. Natural and cheap methods were therefore studied for possible industrial application in decontamination. On account of resistance to fungal growth or aflatoxin accumulation described in the literature for various feed products such as groundnuts, sunflower seeds and soybean varieties, different strains of coconuts were studied for their resistance to fungal growth and aflatoxin accumulation by inoculation of grated coconut with different fungal strains under different conditions of incubation and examined at single or several incubation times. No reproducible results were obtained in any of the experiments. The strains of coconut which showed relative resistance on incubation for a fixed number of days showed equal susceptibility on time course studies. The possible reasons for these discrepancies are discussed. The literature on the resistance of other seed products is also controversial, and it is suggested that time course studies of aflatoxin accumulation may minimize errors in such determinations. The applicability to coconut products of the age old practice of smoking for the preservation of foods was studied by inoculating smoked grated coconut, smoked broth media or broth media containing smoked water for its efficiency in inhibiting aflatoxin accumuulation. The treatment was found to inhibit aflatoxin accumulation to a greater extent than mycelial growth. The moisture content of coconut kernels appeared to be critical as moisture levels above 40percent and 15percent supported aflatoxin accumulation in smoke dried and electrically dried kernels respectively. The inhibition of aflatoxin accumulation by coconut charcoal smoke was found to be apparently due to water soluble fractions in smoke as smoked sterile water or broth were also effective in inhibition of aflatoxin accumulation. As spontaneous loss of aflatoxins was previously observed during storage of contaminated coconut the possible cause of the loss were investigated by storing coconut oil under different laboratory conditions. Of the various natural factors studied (heat, light, enzymic activity) only sunlight was found to be effective. The effect was studied in detail. Detoxification of aflatoxins in coconut oil was brought about by subjecting oil in the form of a thin layer of about 2-4 cm. in thickness under experimental conditions to sunlight. The quality (FFA. coolur) of the treated oil was the same as the untreated oil. Pilot plant experiments with the method are suggested for possible adaptation to industrial decontamination. With solid products, copra and poonac, sunlight was not effective in degrading aflatoxin probably because the sunlight did not penetrate solid particles as effectively as through liquid oil. Some strains of Aspergillus flavus isolated from local copra were found to exhibit intense blue fluorescence on hyflosupercel toxigenicity screening plates. These strains were cultured on grated coconut and the metabolites were extracted. A blue fluorescent compound having different but close Rfs with aflatoxins in several TLC solvent systems was isolated. The compound produced fatty changes in the livers of ducklings after oral dosage. The spectral characteristics and the TLC data suggest it to be a hitherto undescribed factor of possible toxicological interest. The lines on which further research in the field of aflatoxins in coconut products are indicated.Item Rapid diagnosis of typhoid in a poorly resourced clinical microbiology Laboratory(University of Peradeniya: UP(MED)., 1996) JAYASEELAN, SFour hundred adult patients from General Hospital, Kandy and Base Hospital, Trincomalee were studied for a one year period. But only 159 patients were included in the study because the others have not had confirmative alternative diagnosis. Whole blood, blood clot, urine and stool sample were obtained from patients for culturing. These patients were classified into 3 groups according to the clinical and laboratory findings. Group 01 comprised 30 patients ,,-ho .were definitively diagnosed as having typhoid/paratyphoid by isolation of Salmonella typhi or S. paratvphi A from blood. Group 02 consisted of 50 patients who had a strong presumptive diagnosis of typhoid, ie., a clinical illness suggestive of typhoid with an "O" antibody titre of \>1/240 in the SAT and isolation of S .tvphi from urine. Group 03 included 79 patients whose blood culture was negative and had proven non - typhoidal illnesses in whom typhoid was considered in the differential diagnosis. An improved blood culture system was developed using Tryptone Soya broth-Sodium Polyanethol Sulphonate combination. Thirty eight S.tvphi and two S.paratvphi A were isolated from the patients' blood. S.typhi was also isolated from stool cultures of 4 patients and a urine culture of one patient. Antibody status of group 1, group 2 and group 3 were assessed by the single Widal tube agglutination test. Widal testas maximally efficient at "0" antibody titre of 1/480 and "H" antibody titre of 1/120. At "0" titre of 1/480 Widal test had sensitivity of 92.0per cent, specificity of 94.9per cent, positive predictive value of 85.1per cent, negative predictive value of 97.4per cent with efficiency of 94.2per cent. At "H" titre of 1/120 Widal test had sensitivity of 80.0per cent, specificity of 94.9per cent, positive predictive value of 83.3per cent, negative predictive value of 93.8per cent and efficiency of 91.3 per cent.Bacterial antigen detection was carried out by coagglutination (COAG) procedure from blood culture broth, clot culture broth, urine supernatant and serum in parallel to the routine cultures. In addition, COAG was done on 24 hour growth on Kligler Iron Agar (KIA) slopes. Twenty six out of 26 blood culture supernates (100per cent) became COAG positive 1 day before the presumptive blood culture results. Eighteen out of 18 clot cultures supernates (100per cent) supernates were positive by COAG 1 day before the presumptive clot culture results. None of the 30 non S.typhi and S.paratyphi A blood and/or clot culture isolates were positive with the COAG. Therefore, COAG is 100per cent sensitive, specific and rapid for identifying Salmonella typhi in blood and clot cultures. Sixteen out of 28 urine samples (57per cent) in group 1, 37 out of 50 urine samples (74per cent) in group 2 and 23 out of 76 urine samples (30per cent) in group 3 became positive for COAG test but S.tvphi was isolated only in one urine sample belonging to group 1. Although Urine COAG has a relatively high sensitivity in groups 1 and 2, false positive reactions occurred all groups (1, 2 and 3) mainly from patients who had fever at the time of urine collection. This results indicate that something other than the presence of antigens of S.typhi or S.paratvphi A gave positive reaction. Further studies are necessary to eliminate the false positivity problem in order to improve the efficiency of this test in all 3 groups. The COAG test was not helpful in serum as all patients with typhoid gave negative results. 100per cent serological identification of all the 115 S.tvphi isolates and 05 S.paratvphi A isolates were made using COAG reagents. 134 non S. tvphi and S. paratvphi A enterobacteriaceae isolates were negative by COAG. The "0" antigen gave weakly positive results in 5 minutes with 9-0 coated COAG reagent. Ninety four out of one hundred and fifteen S.tvohi isolates (85.2per cent) were positive on direct testing. A further 14 out of twenty one (66.7per cent) required 50per cent ethanol treatment and the rest (33.4per cent) immersed in a boiling water bath for 10 minutes. d-H reaction were much stronger (2+) and appearing wi thin 2 minutes. The 5 strains of S. paratvohi A gave strong positive reactions for both "0" and "H'T antigens. Although COAG has been explored in the diagnosis of typhoid, its value in the Sri lankan diagnostic laboratory has not hitherto been tested. Although insensitive in antigen detection in serum, it appears to have a potential value in antigen detection in urine which needs further study. However, its main value at present could be its use in the laboratory both for early identification of positive cultures and for serological identification of likely isolates of S.typhi and S.paratyphi A.Item The Effect of intrauterine infection on neonatal thyroid function(University of Peradeniya: UP(MED)., 1980) DE SILVA, LVKIntrauterine infections were diagnosed by the determination of cord serum IgM levels. The incidence of intrauterine infection was found to be 11per cent in Kandy District. The functional status of the foetal thyroid in relation to intrauterine infection was assessed by the determination of cord serum T3, T4 and TSH levels. It was observed that when cord serum IgM levels were elevated, the levels of TJ and TSH were also elevated. However, no significant difference was seen in the T4 levels. Since IgM does not cross the human placenta. cord serum IgM is of foetal origin and elevated levels of cord serum IgM levels are non-specific indicators of intrauterine infection. Therefore, it was concluded that intrauterine infections probably affect foetal thyroid function. Nevertheless clinical symptoms of altered thyroid function were not seen in any of the neonates studied. Antibodies to thyroid microsomal antigen were seen in 4 neonates with elevated levels of cord serum IgM. In 2 of these neonates, thyroid microsomal antibodies were not seen in the corresponding maternal sera, suggesting a foetal autoimmune response to thyroid microsomal antigen. By determination of specific IgM antibodies in cord serum it was shown that filarial antigens cross the human placenta. It is unlikely that such passage of antigens can establish an infection in the foetus. but may have important implications in the maturation of the immune system. This study therefore. shows that foetal thyroid activity is affected by intrauterine infection. Further. the passage of filarial antigens across the human placenta is also shown.Item The Effects of early clinical training on cognitive ability in anatomy and physiology(University of Peradeniya: UP(MED)., 1983) BABAPULLE, CJThe main objectives of the study were to determine the effect of early clinical training on the acquisition of cognitive abilities in structure and function of (selected parts of) the human body and on the development of perceptual motor (clinical) skills. Clinical training was provided under controlled conditions to three stratified and randomly matched groups in respect of three instructional topics (cardiovascular, respiratory and nervous systems). For each system, one group had clinical training before the lectures, another had clinical training after the lectures, whilst a third group was exposed to lectures only on that system. The groups were randomised in respect of the instructional method for the three systems. The results show that, in respect of cognitive ability the groups which received clinical training before the lectures, performed significantly better than the group Which received lectures only. Two of the three groups which received clinical training after the lectures performed significantly better than the lecture only group. There was no significant difference between the groups which received clinical training though the mean scores of the group that received clinical training before the lectures was higher than the group which received the clinical training after the lectures. With respect to the development of perceptual-motor (clinical) skills the groups that received clinical training performed significantly (p "0.001) better than the control I (lecture only) group. There was no significant difference between the groups which received the clinical training, though the groups which received the training after the lectures had mean scores above that of the group which received the training before lectures.The other purpose of the study was to determine the effects on short and long term retention the former being evaluated immediately after instruction and the latter three months after the conclusion of experimental treatment. With respect to sort term retention in cognitive ability all groups showed significant gains ( p \< 0.01) after instruction, on all three system, With regard to long- term retention there were slight games in cognitive ability in respect of the cardiovascular and respiratory systems, with a slight drop in knowledge in respect of the nervous system. Where perceptual-motor skills were concerned lecture only (contro1.) groups showed mean sc0re gains over 'their first performance though their performances were always significantly poorer than the clinically trained groups Adequate long-term retention of skills was observed in the clinlcul1y trained úgroups - there being no significant change in four of the six groups, over the three month period. One group however recorded significant drops in mean scores (p \<0.05) on two occasions with regard to prediction of performance, the result: revealed that post instructional scores cannot reliably be predicted from pre-instructional score in respect of cognitive ability. However, on re-test three months after the post-instructional tests reliable predictions of scores could be made in respect in cognitive ability in the cardiovascular but not of the nervous system. Scores on a second clinical test (three months after the first) cannot be reliably predicted from scores on the first test. The overall analysis revealed that probably about 28 percent of the variance in cognitive ability can be attributed to clinical training while the training would explain nearly 85percent of the variance in respect of perceptual-motor (clinical) skills .Item A Study of the carbohydrate and serine metabolism in relation to starvation in staphylococcus epidermids(University of Peradeniya: UP(MED)., 1979) SIVAKANENSA, RItem Size of particles produced by mastication of food(University of Peradeniya: UP(MED)., 1976) JIFFRY, MTMItem Histology and histopathology of the human submandibular salivary gland based on stereological Techniques(University of Peradeniya: UP(MED)., 1995) ATTELE, AThis investigation quantifies the spatial distribution and inhomogeneity of tissue constituents of the human submandibular salivary gland in three states: normal, calculus sialadenitis and pleomorphic adenoma. With the aid of a light microscope and an ocular graticule for point counting, the basic stereological parameter of volume density was computed for 8 histological components. The volume density represents the distribution and the biologic variation its inhomogeneity. Within the 20-30 year age group, the normal submandibular gland does not show a difference in distribution of serous or mucous acini between the topological exterior and interior. If we assume a one-to-one relationship between acini and intercalated ducts, then the intercalated ducts are also equally distributed between the (topological) exterior and the interior. Thus, from the perspective of development of the gland, it may be deduced that primitive terminal ducts have an equal potential to form acini in the exterior or interior of the gland. The volume density of serous acini is as much as 11 times more than that of mucous acini, which confirms the wide disparity in the prevalence of, serous acini compared to mucous acini reported in qualitative studies. In calculus sialadenitis, the volume densities of serous acini and mucous acini diminished by 58 percent and 85 percent, respectively. The volume densities vf fibrous tissue and chronic infiamatory cells rose from 14.33 percent to 48.54 percent, 0.3 percent to 9.30 percent, respectively. The relative loss is higher for mucous acini than for serous acini; evidencing that mucous acini are more susceptible to inflammatory changes than serous acini. It is interesting to note that the biological variation of mucous acini does not undergo a change in sialadenitis, i.e., the disease process has equally affected mucous acini throughout the gland. To compensate for the loss of secretory function ducts proliferate. This study has identified intralobular ducts as the component contributing to this increase. The biologic variation of intralobular ducts has increased; for, one would expect the proliferation of intralobular ducts to be concentrated among those leading to unobstructed extralobuar ducts. Fibrous tissue, which replaces lost parenchyml elements,has seen an almost 3 fold increase in its volume density. The increase in its biologic variation reflects the inhomogeneous distribution of intralobular ducts. Age was not a factor in sampling, however, age dependent changes were corrected for serous acini; I the corrected data corroborated its remarkable decrease. The volume densities of epithelium and stroma in pleomorphic adenoma were computed, and was used to apply Seifert's classification. The 9 pleomorphic adenomas examined belonged to either type 1 or type 2. Quantifying epithelium and stroma clearly provide a more rigorous basis to interpret and apply Seifert's criteria to classify pleomorphic adenoma. In order to provide for the maximum use of the pathologist's time and effort, the optimal number of Items at the sampling levels of sections and fields were computed. When 10 blocks from each tumour are selected: per block the optimal number of sections turns out to be 7 and the number of fields 2.Item A Lymphoscintigraphic study of the pattern of lymphatic flow in patients with lower limb lymphoedema in Kandy Sri Lanka(University of Peradeniya: UP(MED)., 2001) UDUGAMA, JMCIncreasing numbers of patients with unilateral or bilateral below or above knee lymphoedema with no apparent secondary cause have sought medical help in Kandy, Sri Lanka. Radionuclide Lymphoscintigraphy has emerged in recent years as the standard procedure for the visualization of the lymphatic system in patients with peripheral lymphoedema. Scintigraphic studies using radionuclides to examine the status of the lymphatic system of lower limbs in patients who suffer from lymphoedema in Sri Lanka using an available radiopharmaceutical have not been published. This study explains reasons for different levels of clinical lymphoedema found with each location of lymphoscintigraphic obstruction and compensatory mechanisms responsible for these differences based on lymphoscintigraphic findings. It also documents the prevalence and possible aetiology of lower limb lymphoedema in this group of patients. This study was done on eighty consecutive patients with lymphoedema of lower limbs with no apparent secondary cause, referred from Vascular Clinic of Teaching Hospital, Peradeniya. To asses the main compensatory mechanisms that control the extent of lymphoedema in these patients, the hypothesis of possible lymphovenous shunting was explored by studying the percentage and rate of liver uptake on scintigraphy. Lymphoscintigraphy was performed by injecting 148 MBq. of 99mTc Sulfur Colloid according to a standard protocol using a Gamma camera with a dedicated computer system. Visual assessments of appearance of lymph vessels, nodes and tracer in the liver in each category over time intervals were carried out. The liver uptake percentages were recorded and quantified using a standard formula. To evaluate the compensatory mechanisms taking place to control the progression of lymphoedema at different levels of blocks, possible evidence for collateral flows and Iymphovenous shunting was studied. Based on the demographic structure of this group of patients, it is apparent that lymphoedema in lower extremities were common in young females in 21 - 40 years age group with female dominance (F: M = 30:9) and a family predisposition. A female dominance was found in all levels of lymphoscintigraphic obstruction. These findings would strongly suggest the presence of primary lymphoedema in this group. Non visualization of lymphatics proximally but visualization of lymph nodes more distally suggests distal hypoplasia. Therefore I would suggest that the evidence of obstruction in the medial lymphatics in patients is due to primary lymphoedema in this group and may be an appearance caused by hypoplastic lymphatics or hypoplastic and fibrotic nodes often visualized in this group of lymph nodes. This hypoplastic and fibrotic nodal obstruction was considered the main cause for lymphatic obstruction. Other possibilities included stenosis of the lymphatics or lymph nodal channels consequent to peri lymphangitis or lymphadenitis caused by secondary sepsis. It may be speculated in the clay soil, the aluminum and silica may playa role in the fibrotic process in this country as well and needs to be further studied. Percentage liver uptake in each of the clinical presentation of lymphoedema revealed a distinct pattern. Patients with unilateral below knee lymphoedema with popliteal nodal block, blocks in the lymphatics on the medial, side of the knee and lower vertical set of inguinal nodes showed a different pattern. These groups had significantly higher liver uptake values than even the control groups (p = 0.00 I, 0.0002 and 0.000 I), suggestive of lymphovenous or Iymphnodovenous shuntingThis could possibly account for the lower level of clinical lymphoedema in those with blocks in the inguinal nodes. Since the collateral flow was observed, this would suggest the presence of collateral circulation to minimize the extent of lymphoedema. The fact that increased liver uptake were seen in 'patients with unilateral lymphoedema presenting with lymphatic blocks in the popliteal, medial side of the knee and lower vertical set of the inguinal nodes when compared to control normal limbs clearly suggest early diversion of tracer through into the systemic circulation. This is a strong argument to suggest the presence of lymphovenous shunts or Iymphnodovenous shunts. It also suggests that such shunting may be responsible for the varying levels of lymphoedema in these patients.Item Characterization of toxocara canis antigen and seroepidemiological studies on toxocariasis in children in the Hindagala community Health project(University of Peradeniya: UP(MED)., 2003) IDDAWELA, DRToxocariasis, a zoonotic infection in humans caused by Toxocara canis, T. cati and T. vitulorum of dogs, cats and ruminants respectively, is now recognized as an important childhood infection worldwide. In Sri Lanka, although a few case studies have been reported there is no information on the prevalence of infection in the population and further, the epidemiological factors determining transmission are unknown. Diagnosis of toxocariasis is currently based on serology to detect antibodies. The widely used assay is the ELISA test based on the excretory-secretory antigens of second stage larvae derived from culture (TES-ELISA). However, this assay cannot differentiate between infections caused by different Toxocara species and further cross reactions with other intestinal nematodes have been documented. The latter, although small, could be significant in Sri Lanka. Thus this study addresses the isolation of a T. canis species-specific ES antigen and the development of an ELISA assay based on this antigen to validate seroprevalence obtained on the conventional TES-ELISA in a defined childhood population in Sri Lanka. The ES antigens of T. canis, T. vitulorum, Ascaris lumbricoides and Necator american us larval antigens were separated on SDS-PAGE and immunoblotted. An antigen TeES-57 was identified that was specific for T. canis and was not shared by the other ES or larval antigens used. Using this product a specific anti serum was produced in rabbits and a double sandwich ELISA developed. This was validated using known seropositive sera from patients with toxocariasis. A seroepidemiology study was carried out in 1020 children aged 1-12 years in 7 study sites at the Hindagala Community Health Project (HCHP) between August 1998 to August 2000. The toxocariasis seroprevalence was 43per cent with 166per cent showing high antibody levels. On assessment of risk by unconditional logistic regression analysis. the age at the highest risk was the 7- 9 year age group (adjusted odds ratio 3.0820; CI= J .95-4.87). Dog ownership, especially puppies (adjusted odds ratio 29.28; CI= 7.40-] 16.0), was a highly significant risk factor and geophagia-pica (adjusted odds ratio 6.3732; CI= 3.87- 10.50), was also shown to be a significant risk factor to infection. Sex and socio economic status of the family were found to be confounding factors. Family clustering oftoxocariasis was significant (X2 = 88.000; P= 0.000) Common childhood symptoms comprising abdominal pain (45per cent), cough (30per cent), limb pain (23per cent) and skin rashes (20per cent) were shown to be higher in the seropositive group indicating that toxocariasis causes covert morbidity in these children. These findings are, overall, applicable to other inhabited areas in Sri Lanka. However, it is recommended that similar studies be extended to the dry zone as the hot and dry climate, by limiting survival of infective eggs in the soil, could affect prevalence More importantly, prevalence studies are required in the agricultural areas with a high buffalo population as T. vitulorum of the buffalo could account for human toxocariasis. Using the TeES-57 based ELISA it is demonstrated that 9]per cent of the seropositives in this study area were due to the dog parasite T. callis. These studies have clearly shown that along with rabies and dirofilariasis, toxocariasis is an important zoonotic health hazard from dogs in Sri Lanka and preventive measures directed towards dog fouling of public places is urgent with awareness of veterinarians, pet owners and public health personnel. The control of stray dogs is mandatory to limit transmission to humans.Item The Aetiology of cataract and the effect of prednisolone on the development of cataract(University of Peradeniya: UP(MED)., 1983) ANGUNAWELA, IIInvestigations were carried out to clarify the role of auto immune phenomena in the pathogenesis of cataract in the adult human lens. Studies were carried out to determine the presence of serum antibodies to lens protein in patients with senile cataract, in patients with diabetes mellitus with and without cataract and in healthy adult (non-diabetic and free of cataract) control subjects. The sera from these subjects were investigated for the presence of antibodies to lens protein 'using the interfacial test and the gel diffusion technique. Non-specific antibodies were removed by adsorption of sera in homogenised rat liver. A high proportion of healthy adults were found to have antilens protein antibodies (44.4per cent by the gel diffusion method). In contrast, the patients with cataract and the diabetic patients with no cataract demonstrated double this incidence, while all diabetic patients with cataract showed the presence of antibodies. The antigenicity of the lens protein waS found to be weak, and this feature is discussed in relation to the proteins of normal lenses as well as cataractous and diabetic lenses. The possible methods by which lens antigen is released to evoke an antibody response is also discussed. The auto antibody status and the role of lens protein antibodies in heal thy humans is discussed. The possible causes for the higher incidence of anti-lens protein antibodies in the patients with cataract, and in the diabetic patients with no clinical evidence of cataract are considered, in relation to cataract formation. Homogenates of cataractous lenses when investigated for the presence of immunoglobulins, revealed the presence of both Ig G and Ig M immunoglobulins, the former probably to a greater extent. Fluorescent microscopy, on cryosections of senile and diabetic cataractous lenses, revealed the presence of immunoglobulins within the lens., The role of immune complexes within the lens in relation to the pathogenesis of cataract is discussed. The antigen in the immune complexes isolated from homogenized lens was characterised by the SDS-polyacrylamidegel-electrophoresis method. A single band was consistently obtained and the molecular weight of the protein was estimated to be between 35,000 and 40,000. An animal model was used to determine the effects of anti-human lens protein antibodies on the lens, and to ascertain the effects of prednisolone on the production of antibodies in immunized animals. Ten rabbits were immunized with human cataractous lens homogenate in Freund's adjuvant according to a schedule. Half the immunized animals were treated with prednisolone. Only one out of the five animals that were treated with prednisolone produced antibodies. On slit lamp examination of the lenses of all 12 rabbits under investigation, two out of the six rabbits who produced anti-lens antibodies showed cortical lens opacities at the end of 16 weeks. The strong possibility of auto-antibodies to lens protein being of aetiological significance in the pathogenesis of cataract is discussed.Item The Chronological age and sequence of eruption of the permanent dentition of children in the Kandy district of Sri Lanka(University of Peradeniya: UP(MED)., 1988) NANAYAKKARA, CDStudies regarding chronology of tooth eruption have been reported from many parts of the world. This data has been of importance in clinical, anthropological and medico-legal work. Use of the chronology of tooth eruption as a measure of maturational status will prove to be of even greater importance. Information regarding the chronology of eruption of the permanent dentition in Sri_ Lanka is scanty. In the present study 2860 males and 2767 females, 5 to 16 years of age, in the Kandy district of Sri Lanka were examined in order to establish norms for tooth eruption for Sri Lankan children. The children were grouped according to sex, age and socio-economic status. The times of eruption of teeth were calculated using a modification of Karber's method. All teeth in the females erupted significantly earlier (P \< 0.0 I) than the corresponding teeth in males. An average difference of 4.4 months between the mean age of eruption of the males and females was observed showing females to be more mature than males at any given age with regard to tooth eruption. The existence of this highly significant sex difference necessitated ~he tooth eruption to be sex specific. A definite influence of the socio-economic status on tooth eruption was evident from the results of this study, the children of the high socio-economic group showing advanced eruption times. The sequence of eruption of teeth has been shown to be group specific. The sequence of eruption established for the Sinhalese arc as follows : Males, Females (Refer the original thesis) Using the relationship between the clinical emergence of teeth in the oral cavity and the chronological age a simple measure of maturational status for Sri Lankan children between the ages of 5 and 12 years has been established. The growth curves drawn using heights for males and females of the present study are very similar to the established curves for a representative sample of Sri Lanka. The sample from the Kandy district may therefore be also taken as representative of the population of Sri Lanka.Item A Study of streptococcus and it's role in dental caries in Sri Lanka(University of Peradeniya: UP(MED)., 1977) DENIPITIYA, JCLItem Labour force participation and reproductive behaviour of women in an agrarian community of Sri Lanka(University of Peradeniya: UP(MED)., 1992) ABHAYARATNE, ASPItem Aetio-pathology of respiratory infections in pigs in Sri lanka(University of Peradeniya: UP(MED)., 2011-02-07) DILEEPAN, MItem A Pathological and bacteriological study of caprine pneumonia in Sri Lanka(University of Peradeniya: UP(VET)., 1981) HORADAGODA, NUItem A Study on histamine production and control measures for fish and dried-fish and the effects of processing on histamine(University of Peradeniya: UP(MED)., 1999) GUNARATNE, S