Browsing by Author "Yasawardene, S.G."

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Balangoda man: reconstructed from fossils of Bellan-bandi Palassa, a Mesolithic heritage site in Sri Lanka
(University of Kelaniya, 2008) Kanthilatha, W.S.P.Y.N.; Yasawardene, S.G.; Pathmalal, M.M.; Adikarie, G.
The dental analysis of prehistoric skeletal remains of Pothana, Sigiriya, Sri Lanka
(12th Annual Research Symposium, University of Kelaniya, 2011) Chandimal, K.M.; Yasawardene, S.G.; Adikari, G.
A detailed analysis of dentition is of utmost importance in finding answers to specific questions regarding heath status, dietary preferences, behavioral patterns and biological affinities of prehistoric populations, and is of paramount importance to archaeologists. Dental remains from prehistoric skeletal remains at Pothana date back to more than 4500 BP were used in this study. Permanent teeth (54 in no.) obtained from these adult human skeletal remains were studied. The detailed morphological and metrical analysis of permanent dentition was done and the crown index (B-L/M-Dx100) and robustness values (B-L x M-D) calculated for each tooth by following the methods described in Bass 2005 and Marting and Saller 1957 -1959, using measured mesio-distal and bucco-lingual diameters of lower molar teeth. The morphological traits: shovel shape of incisors, carabelli‟s cusp, taurodontism, para molar cusps and cusp number and molar groove pattern of mandibular teeth of the dentition were studied. The pattern of dental attrition, staining & discoloration of teeth and pathological conditions were studied. The crown surface area (robustness value) of available lower teeth decreases Molar 1 (M1) > M2 >M3 and the crown index decreases M3 > M2 >M1 of Pothana skeletal remains. Five cusp patterns were observed in the available first lower molar and the four cusp pattern was observed in lower second and third molar teeth. The upper molar showed the four and three cusp pattern. The groove patterns were not observed on first and second molar due to high stage of attrition but Y groove pattern was observed on 3rd lower molar teeth. There was no evidence of crowding, taurodontism, shovel shaped incisors, artificial deformations, carabelli‟s cusp, para molar cusps. The attrition differential between the anterior and posterior dentition was clearly evident. High attrition was observed in most of the anterior teeth in many instances rather than in molar and premolar. This is comparable to the dental attrition pattern of Pomparippu population reported by Lukacs 1973, and the dental attrition pattern of Balangoda population by Kennedy 1986. This indicates the higher usage of anterior teeth by extinct population than the post canine dentition. The cause for the higher wear pattern on anterior teeth may be due to the higher usage of incisors and canines as tools to manipulate or to hold various objects. The pathological conditions including carious decay, periodontal diseases were absent in the teeth samples from Pothana. This is comparable to the reported good dental heath state of Balangoda population by Kennedy 1973, and contrasts with the low dental health of Pomparippu population described by Lukacs 1973.
The determination of age, sex and stature of prehistoric human skeletal remains excavated from Sigiriya Potana in Sri Lanka
(Sri Lanka Association for the Advancement of Science, 2009) Chandimal, K.M.; Yasawardene, S.G.; Adikari, G.
The distribution of ABO and Rhesus (Rh) blood groups in purana inhabitants of Sigiriya, Sri Lanka
(12th Annual Research Symposium, University of Kelaniya, 2011) Chandimal, K.M.; Yasawardene, S.G.; Adikari, G.
The ABO blood group system was discovered in 1901, and since then, has been of major importance in medicine. Racial and ethnic differences in blood type and composition are documented. The frequency with which blood types are observed is determined by the frequency with which the alleles of the ABO gene are found in different parts of the world. The blood type purity depends on migration, diseases, inter-relational reproductive opportunity, traditions and customs, geography, and the initial assigned blood type. The purana population in Sigiriya who face imminent threat of extinction, trace their ancestry to the times of the Sinhalese King of the 5th Century A.D. This study was carried out to determine the distribution of ABO and Rh phenotype in purana inhabitants of Talkote, Diyakepilla, Alakolaweva,Pidurangala, purana villages at the foot of Sigiriya rock. One thousand and ten purana inhabitants belonging to purana pedigree were included in this study and those who belong to other pedigrees were excluded. The individual selection was based on verbal pedigree analysis and pedigree was traced back to at least three generations. Capillary blood was used to determine the individual blood group by using commercially available anti A, anti B, anti D antibodies. More than 98% of purana population showed Rh positivity while the distribution of O, B, A, and AB phenotypes were 55%, 32%,10% and 03% respectively. The percentage distribution of blood group phenotype O of purana population is higher than the reported values of Sinhalese-45%, Tamils-39%, Muslims-42% and Burghers-45% in different racial groups in Sri Lanka, reported by N.S De Zoyza in 1985. The reported value of blood group O in vedda group is 47% according to Weber 2005, while the Australian Aborigines being 61% (World Blood Bank record). The percentage value of blood group phenotype A is comparable with the values of Veddas (9.8%) reported by Weber 2005 and this is contrasting with other racial groups in Sri Lanka, value being of more than 20% of each population. The percentage of phenotype A in purana inhabitants in Sigiriya is comparable with the Sakai (Malaysia), Nicobarese (Nicobars) primitive groups in Southeast Asia reported by Weber 2005. The percentage value of AB phenotype of purana inhabitants of Sigiriya is comparable with the Vedda group in Sri Lanka being 2% and Khmer (Combodia) primitive groups in Southeast Asia reported by Weber 2005. The blood group distribution of purana inhabitants confirms their isolated nature with minimum migration, inter-relational marriages and reproductive opportunity.
Extraction and analysis of ancient DNA from human remains from the Polonnaruwa historic site in Sri Lanka
(Sri Lanka Association for the Advancement of Science, 2012) Chandimal, K.M.; Yasawardene, S.G.; Illeperuma, R.
Extraction and analysis of ancient DNA from human skeletal remains from Sri Lanka
(12th Annual Research Symposium, University of Kelaniya, 2011) Chandimal, K.M.; Illeperuma, R.J.; Yasawardene, S.G.
Analysis of ancient DNA (aDNA) gives archaeologists and anthropologists alternative and innovative ways to interpret and understand the past. The postmortem instability of nucleic acids, presence of inhibitory factors for analysis and the contamination with modern DNA prevent authentic and high recovery of undamaged DNA from archeological specimens. Ancient DNA is heavily modified over time, mainly due to spontaneous hydrolysis and oxidation and consequently, most such specimens do not contain any Polymerase Chain Reaction (PCR) amplifiable endogenous DNA while those that do amplify, generate only fragments in 100 – 500 base pairs in size. Nonetheless, the preservation rate of DNA in human remains is very low under tropical conditions in Sri Lanka due to environmental conditions of high temperature and high humidity. The present study attempts to optimize a method of extracting and PCR amplification of DNA from older human skeletal remains. Samples were obtained under strict measures to prevent contamination with modern DNA. A 15year old (15YH) human humerus excavated from a burial site at Kuliyapitiya and a 40year old (40YT) human tibia from the bone collection of Department of Anatomy, Faculty of Medical Sciences, University of Sri Jayewardenapura, were analyzed. DNA was extracted by a modified Phenol / chloroform method from each specimen and was subjected to PCR using nested reactions in generating 4 overlapping fragments between the nucleotide positions 15978 and 16417 of the human mitochondrial genome. The success of PCR amplifications were verified upon agarose gel electrophoresis. At all the four reactions per each bone generated DNA fragments of desired length (378bp, 247bp, 233bp and 233bp). The products were purified and are being sequenced. The present study established methodologies for extracting and analyzing of aDNA which has been exposed to climatic and environment conditions that favor rapid DNA degradation. This optimized methodology is being applied for mtDNA analysis of prehistoric human skeletal remains from Bellan bandi palassa, Fahien lena, Sigiriya Pothana, Miniethiliya etc.
Facial (Prosopic) Index in Purana Inhabitants at the Foot of Sigiriya, Sri Lanka
(University of Kelaniya, 2012) Chandimal, K.M.; Yasawardene, S.G.; Adikari, G.
The physical dimensions of the human body depend on age, gender, race, geography, nutrition and many more factors. Cephalometry is an important branch of anthropometry which involves measurements of the head and face. The facial (prosopic) dimension is an important cephalometric parameter which is used to describe gender and racial differences. The Purana population in Sigiriya who face imminent threat of extinction, traces their ancestry to the times of the Sinhalese kings of the 5th century A.D. This study was carried out to describe facial morphological characteristics of Purana inhabitants living at Talkote, Diyakepilla, Pidurangala and Nagalaweva- Purana villages at the foot of Sigiriya. One hundred and seven (107) adult males and 208 adult female Purana inhabitants belonging to Purana pedigree were included in the study. The individual selection was based on verbal pedigree analysis, and pedigree was traced back to at least three generations and those who had craniofacial deformities were excluded from the study. The length and width of the face of the selected Purana inhabitants were measured by spreading caliper, and the facial index was calculated. In general, Purana female measurements were less compared to male. The face length ranged from 9.5cm to 13.5cm in males and 8.5cm to 12.8cm in females. The face width ranged from 10cm to 16cm in males and 10cm to 14cm in females. Among Purana inhabitants, a minimum facial index of 68 and a maximum of 100 was observed in both genders. The maximum facial index was 99 in males and 100 in females. The mean facial index of male inhabitants was 92 ± 5.1 while female was 90 ± 6.2. The results indicate that the dominant type of facial shape in Purana male and female is leptoprosopic, being 67% in male and 61% in female. Least common type was hypereuriprosopic in male (2%) and female (6%).The difference in mean morphology (facial index), facial length and facial width between the two genders was significant (P<0.05). The facial morphology of male and female Purana inhabitants being leptoprosopic differs from the reported facial morphology of Indian male as mesoprosopic and female as mesoprosopic (Vaishalia et al 2011). This study confirms the ethnic diversity of facial dimensions among different groups and races of human population and gender based variation.
Immunohistochemical localization of α1 nicotinic acetylcholine receptors in lymphoid tissues of humans
(University of Kelaniya, 2011) Thayabaran, M.; Yasawardene, S.G.
Although neuroanatomical studies have indicated the occurrence of nicotinic acetylcholine receptors (nAChR) in mononuclear lymphocytes of humans, no specific subtypes of nAChR or their distribution in lymphoid tissue have been investigated. The identification of α1 nAChR in immune tissues of post mortem samples was done by immunohistochemistry using antibodies against the subunits of nAChRs. The tissues were processed for Hematoxillin and Eosin staining and indirect immunohistochemistry. Monoclonal anti-nAChR (α1 subunit) raised in rat was applied to label the tissues and linked to biotinylated anti-rat IgG. Labeled Streptavidin Biotin method was applied with Diaminobenzidene as chromogen. Skeletal muscle (positive to α1nAChR) was processed as control. The microscopic images of immunostained slides were computerized for digital image analysis. The intensity of the staining was determined based upon a score of 0, 1+ (focal staining, > 10% cells), 2+ (focal to diffuse staining, 10% > 50% cells), 3+ (diffuse staining, 50>100% of cells). Diffused (1+) distribution of α1nAChR was observed in the parenchyma of liver. Similar distribution of α1 nAChR was observed in Peyers patches and the lymphoid aggregation of the posterior part of the tongue. The capsule and red pulp areas of spleen were highly immunoreactive to anti-α1nAChRs, while a low grade immunoreactivity (IR) was observed in periarteriolar lymphoid aggregations and germinal centres. In lymph nodes, the sub scapsular sinus, medullary cords and trabeculae were intermediately IR to α1 nAChR, while in lymphoid follicles it was absent. Overall, the α1 nAChR IR was high in regions predominantly having T cells and macrophages, and it was low in regions having B cell subsets of lymphoid tissues. These findings confirm that the neuroimmune modulation could be brought by the presence of parasympathetic nerves in lymphoid tissues through α1nAChRs. Further investigations are needed using antibodies against different cholinergic components to confirm the complete architecture of cholinergic nerve supply in immune tissues which would be essential in understanding the neuro immune modulation.
Morphology and Morphometry of Purana (Old) Villages: Pidurangala, Thalkote, Nagalawewa and Diyakepilla at Sigiriya Suburbs, Sri Lanka
(19th Conference on Postgraduate Research, International Postgraduate Research Conference 2018, Faculty of Graduate Studies,University of Kelaniya, Sri Lanka, 2018) Chandimal, K. M.; Adikari, G.; Yasawardene, S.G.
The present human population living in Sigiriya suburbs with the Purana surnames such as Aluthgedara, Gamagedara, Undiyagedara, Millagahagedara, Kongahagedara etc are considered as the Purana population whose ancestry could be traced back to the times of Sinhalese Kings of 5th Century A.D (1,450 YBP). The quantitative (morphometrical) and qualitative (morphological) anthropological traits of the Purana populations (n=313) representing Purana villages: Pidurangala, Thalkote, Nagalawewa and Diyakepilla at Sigiriya suburbs were investigated. The quantitative anthropological traits such as height, cranial index, facial index, nasal index and qualitative traits such as skin colour, hair type and colour etc of thePurana population revealed that the Purana populations living in these four villages' possess increased variations. Results analyzed by ANOVA showed higher variations of most of studied phenotypic characteristics (morphometrical) among Purana female populations living in four villages in Sigirya suburbs. Principle component analysis (PCA) confirmed that Purana male populations of Talkote and Diyakepilla are closer in terms of morphometrical characteristics while the inhabitants at Pidurangala and Nagalaweva are quite isolated from the rest of the population. In contrast to male population, PCA analysis of female populations living in four villages are morphometrically placed in different clusters. The gender, pedigree or caste system, geographical location and socioeconomic status have been identified as limiting factors for the extent of phenotypic divergence among the Purana population. When comparing the present findings and other documented studies based on morphological and morphometrical traits of population groups in Sri Lanka, the analysed percentage distribution of each blood groups (A, B, AB, O and Rh) of Sinhalese, Tamils, Muslims, Burgers and the Purana population showed that the Purana population was phenotypically different from the rest of Sri Lankans. The individual quantitative traits (stature, cranial length, cranial breadth, facial height, facial length etc) and qualitative anthropological traits (skin colour, hair type and colour) of the Purana population were observed to be different when compared with other Sri Lankans.
Morphometric and morphological analysis of prehistoric skeletal remains excavated from Pothana, Sigiriya, Sri Lanka
(Sri Lanka Association for the Advancement of Science, 2011) Chandimal, K.M.; Yasawardene, S.G.; Adikari, G.
Pothana-Sigiriya, a prehistoric Mesolithic heritage site in Sri Lanka has yielded three human skeletons dating back to 4500-5000 BC according to radiocarbon (C14) dating. The detailed morphometric and morphological analysis was performed on human skeletons excavated from Pothana, Sigiriya and presently displayed at National Museum Sri Lanka, Sigiriya Museum and at Osteology laboratory, Postgraduate Institute of Archaeology (PGIAR), University of Kelaniya. The skeleton at National Museum with less prominent superciliary arches, the medium sized mastoid process, less prominent muscle attachment sites over the cranium and wide sciatic notch of the pelvic bone was comparable with that of females. The estimated age was around 25–35 years considering the complete eruption of all 3 molars and the wearing pattern. The skeleton presently at the Sigiriya museum with prominent morphological features of highly robust, heavy, prominent muscle attachment sites, the large mastoid process, highly marked superciliary arches, prominent external occipital protuberance and narrow sciatic notch of the pelvic bone was comparable with that of males. Since all three molars were fully erupted and showed no signs of wearing on their occlusal surfaces, the estimated age was around 25–30 years. The cranium displayed at PGIAR is probably female according to observed small size of the mastoid processes. The age and stature estimation was not possible as the available teeth were mineralized and limb bones were not available. Using the measured lengths of restored long bones and applying regression formulae of Trotter & Gleser (1952) and Krogman (1962), the reconstructed height of the extinct female and male is 170 cm and 173.61 cm respectively. This estimated height is more than the mean height of the present day population (164.6 cm and 151.3 cm for males and females reported in Priyanga et al. 2010). The current study confirms reports by Kennedy (1965) that with the male being 164.70 cm and the female 164 cm, Balangoda man was taller than the mean height of the modern Sri Lankan population. This contrasts with the reconstructed mean height of males 140.05 cm of Bellan bandi pallassa skeletal remains as reported by Kanthilatha 2008.