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CRISPR technology for cancer therapy
(Colombo : Sri Lanka Association for the Advancement of Science ,, 2022) Hansika, W.M.S.; Silva, G.N.
Cancer is said to be the second leading cause of global deaths. Even though there are many treatments available for cancer, it is uncertain that cancers are always cured when the treatment ends. Therefore, early detection of cancer with efficient treatments is important to cure the disease and prevent its recurrence. Recent cancer treatments can target rapidly proliferating cancer cells by disrupting their special metabolic processes. However, lack of specificity against cancer cells may result in adverse side effects for such treatments. Therefore, a new therapeutic strategy that selectively targets cancer cells is an attractive treatment option for cancer. “Aerobic Glycolysis” is the major process of cancer cells to achieve their higher energy demands. There are several critical enzymes that catalyze key steps in glycolysis and therefore, targeting one of these enzymes would be an effective approach to suppress cancer progression. Our research focuses on knocking out the regulatory domain of PFK-1 enzyme, which catalyzes one of the main steps in glycolysis. The ultimate objective would be to downregulate the activity of PFK-1 activity and slow down the proliferation of cancer cells. To achieve this objective, we have used the recent genome editing technology, CRISPR/Cas9 to modify PFK-1 gene that will result in a truncated PFK-1 lacking its regulatory domain. Down-regulation of PFK-1 activity may be a safer therapeutic approach to treat cancer over complete inhibition of PFK-1 as the truncated enzyme may still exhibit sufficient catalytic activity for the function of healthy cells yet may have a significant impact on energy-centric metabolism in cancer cells.
Do migratory waterbirds bring parasitic diseases to Sri Lanka?
(Colombo : Sri Lanka Association for the Advancement of Science ,, 2022) Sepalage, C.S.; Yapa, W.B.; Dayawanse, P.N.; Seneviratne, S.S.; Nitsche, A.; Perera, I.C.
Mannar is a place with rich bird diversity in Sri Lanka. Many migratory birds come to Sri Lanka during the migratory season from August to April to avoid the harsh environmental conditions in their native countries. These migrants closely associate with the resident animals during their stay in Sri Lanka by sharing the same roosting and foraging habitats such as forests and water bodies. Ducks, Gulls, and Flamingos are the common aquatic migratory birds found in Mannar. These birds arrive from the far east, north, and central Asian countries covering the central Asian flyway. Due to the different origins, these migrants can carry many infections posing a threat to resident animal where they land. A research team from the University of Colombo, jointly with the Robert Koch Institute, Germany initiated a project to identify these parasitic infections from December 2021 to March 2022. We collected bird droppings to identify parasites in the gut of the migratory water birds. Samples were analyzed at the IDEA Laboratory, Department of Zoology and Environment Sciences at University of Colombo. Capturing and handling of birds were done by a trained ornithologist. Finally, we have identified several parasites that can cause infections in many animals, including humans. For example, duck samples analyzed were positive for parasitic worms which can cause diarrhea, nausea, anemia, seizures, and weight loss. Resident and farm animals could easily get infected by associating infected environments. It is important to continuously survey the parasites that the migratory waterbirds carry into our country to see whether there’s a real threat posed by them on our native wildlife.
Development of concentrated herbal tea based on refuse tea, BOPF, and Dust 2 tea grades incorporated with Allspice, Mint, and Ginger
(Colombo : Sri Lanka Association for the Advancement of Science ,, 2022) Dharmadasa, R.M.; Imesha, B.P.A.
Despite being one of the biggest tea exporters in the world, Sri Lanka currently exports the majority of its tea in bulk without much value addition. Consequently, any effort to increase the value of tea could result in higher earnings for the nation. Accordingly, we have focused on developing a concentrated tea with three distinctive flavour fusions: allspice leaves, mint, and ginger. Numerous bioactive compounds with significant antioxidant and therapeutic properties can be found in these spices. For the study, Refuse tea, BOPF and Dust 2 grades were used to develop the tea base and it was incorporated with the studied flavor fusions. Initially, the amounts of ingredients were optimized according to the preliminary sensory evaluation. Simple boiling method was used to extract the tea samples. Sugar was added and macerated until it reached a final concentration. Dried Allspice leaves (4%), fresh ginger (32%) and mint (24%) were added and kept in less than 40 °C for 10 minutes. Then the concentrated herbal tea was filtered and bottled following refrigeration at 4 °C. Organoleptic, physicochemical characteristics and shelf life of the tea samples were tested. As per the results, sensory attributes like mouth feel, overall taste, and overall acceptability depicted a significant difference between the grades while no significant difference was observed in appearance, color and aroma. The concentrated herbal tea based on BOPF grade was selected as the most preferred sample. Proximate parameters such as Carbohydrate content and energy indicate significant difference within grades and high values comprised in BOPF grade (33.5% and 135 kcal/100mL). Physicochemical characteristics like viscosity, color, antioxidant capacity, total flavonoid content depicted significant difference within three tea grades. We can conclude that unique flavor combinations provided pleasant sensorial experience to concentrated teas while the tea grades used directly impacted on the end quality of the product.
Impact by value-added coconut (Cocos nucifera L.) jaggery on blood glucose level
(Colombo : Sri Lanka Association for the Advancement of Science ,, 2022) Hewa Pathirana, H.P.D.T.; Wijesekara, I.; Yalegama, L.L.W.C.; Jayasinghe, M.A.
Consumer awareness of low sugar-containing food intake has increased, and people use different types of rating method to identify the quality of food such as Glycemic Index (GI). GI shows how quickly each food intake impact on your blood sugar level. Three categories of GI could be identified such as low, medium, and high. We have studied GI of different types of coconut jaggery such as jaggery prepared from traditionally collected coconut sap with hal (Vateria capallifera) bark (HAL Jaggery), valueadded coconut jaggery with 0.2% cinnamon (Cinnamomum zeylanicum) (CIN Jaggery) and nutmeg (Myristica fragrans) (0.05%) added jaggery (NUT Jaggery). Twenty-one healthy human volunteers (female: 9 and male:11) aged between 20 to 40 years were used to evaluate the GI of jaggery samples after analyzing fasting blood glucose concentration, body mass index, and a simple blood test that measures your average blood sugar levels over the past 3 months (HbA1c). After fasting, intake of food sample blood sugar concentrations were analyzed during 2 hr duration while keeping 30 min gaps to evaluate the fluctuation of blood sugar concentration. When we look at the results of initial blood analysis, participants of the study had healthy limits of fasting blood glucose concentration and HbA1c values. The total and digestible starch percentages were similar in three types of jaggery, but higher resistant starch content was observed in HAL Jaggery. The peak value of glucose concentration of three types of jaggery, were 143.33±12.61 mg/dL, 153.07±15.25 mg/dL and 145.13± 22.39 mg/dL, respectively, in HAL, CIN and NUT Jaggery types. The results confirmed that the GI of HAL (55.79±20.36), NUT (57.56±22.95) and CIN (59.45±20.36) Jaggery was similar, and all three types can be categorized as medium GI sweeteners.
Exposure to aerosol pollution and reported respiratory symptoms among segments of urban and rural populations in Sri Lanka
(Sri Lanka Institue of Architects:Colombo, 2007) Perera, G.B.S.^i; Emmanuel, R.; Nandasena, Y.L.S.; Premasiri, H.D.S.
Health effects due to exposure to air pollution have become a growing concern as an ill-effect of rapid urbanization in several regions of Sri Lanka. Evidence suggests that exposure to particulate matter and other aerosols such as SO 2 and NOx have increased in urbanized areas in Sri Lanka. But presently adequate evidence to show the association between health effects and air pollution is not available. In this ecological study, we present the micro-level picture of aerosol pollution obtained by using an interviewer administered questionnaire survey and comparing the results against exposure to aerosols. Secondary data were gathered on Sri Lankan health issues from the Ministry of Health to understand the most common causes of mortality and morbidity in the city. Symptoms and the medical diagnosis information were collected from randomly selected probability proportionate samples of five categories of street users (commuters in buses, three wheelers, outdoor venders, shop keepers and residents) in an urbanized area of Colombo and in a rural area of a peripheral district. Exposure levels were measured using passive air samplers in both locations. Moreover active sampling measurements of curbside levels of Total Suspended Particulate Matters (TSP), Sulfur Dioxide (S0 2 ) and Nitrogen Dioxide (N0 2 ) were collected in urbanized area. Aerosol exposure of urban and rural dwellers in all five categories, have shown significant differences in levels of SO (p = 0.001) and N0 2 (p < 0.001). Three wheeler drivers and shop keepers showed no significant difference in SO* levels in both locations (p = 0.045 and p = 0.113) while buses at both locations showed the highest NOz and S0 2 levels at both sites while houses had the lowest levels. Further analysis showed that the exposure levels of bus drivers significantly vary (S02 - F= 13.399, p = 0.001; NO2 , F =52.283, p < 0.001) on the route characteristics (urban, urban to sub urban and rural). Urban street users had higher prevalence of cough (p < 0.001, OR = 3.43, CI = 2.29 - 5.15) and phlegm (p <0.001, OR = 2.19, CI = 2.29 - 5.15). Wheezing among city dwellers was 20.5% and among rural dwellers was 13.7 %(p = 0.043, OR = 1.62, CI = 0.99 - 2.67).There was no significant difference in breathlessness over the different locations. The association might be overridden by localized risk factors such as difference in lifestyles among the urban and rural populations such as the higher number of people using wood as cooking fuel being in the rural site. Short- and long-term mitigation strategies are needed to reduce people's exposure to such air pollutants. The outcome of this study has been extended for necessary policy implications and mitigation guidelines by introducing recommendations of land use development in the city limits.