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- PublicationThe effect of 660nm light-emitting diode irradiation on human gingival fibroblast cell proliferation(2025-01)Light therapy has become a common treatment modality in various medical fields, including dermatology, dentistry, and cosmetics. This study aimed to evaluate the effect of 660 nm ligh-emitting diode on the proliferation and viability of human gingival fibroblasts in vitro. The cells were irradiated with 660nm light-emitting diode for 60 and 120 seconds 24-hours post-seeding. After 24- and 48-hours irradiation, cell count, and viability were determined. The results then were analysed using a one-way ANOVA test (p < 0.05). The findings revealed a significant increase in cell proliferation rate and viability in the irradiated groups compared to the control group, with the 120 seconds irradiation group showing the highest enhancement at both time points. These results suggest that 660 nm LED light can effectively promote the proliferation and viability of human gingival fibroblasts, highlighting its potential as a valuable tool in regenerative dentistry and periodontal therapy
- PublicationThe evaluation of etlingera elatior flower (bunga kantan) aqueous extract (EEAE) effects on cognitive impairment improvement in diabetic rats (pilot study)(2025-01)Diabetes mellitus (DM) is a global health concern that affects individuals across all countries, sexes, and age groups. It increases the risk of developing multi-organ complications, including cognitive impairment, which is often linked to hyperglycaemia, oxidative stress, insulin resistance, neurovascular dysfunction, and neuroinflammation. Although the pharmaceutical antidiabetic drugs are effective in controlling blood glucose levels, they are often associated with various side effects. Hence, the trend of using medicinal plants that contain bioactive compounds to improve diabetes-induced cognitive impairment is increasing due to their minimal side effects and cost-effectiveness. This pilot study aims to evaluate the effects of Etlingera elatior flower aqueous extract (EEAE) on improving cognitive impairment in diabetic rats. Nine Sprague-Dawley male rats were randomly separated into three groups (n=3/group): (1) normal control group, (2) diabetic control group, and (3) diabetic treatment group receiving 1000 mg/kg EEAE orally for 6 weeks. The DPPH assay was used to measure the antioxidant activity of EEAE, which showed that EEAE exhibited moderate antioxidant potential. Furthermore, EEAE treatment showed slight improvements in fasting blood glucose (FBG) levels and body mass index (BMI) compared to the diabetic control group. Additionally, it improved all parameters related to spatial learning and memory in the Morris Water Maze (MWM) test Histological examination of brain tissue using haematoxylin and eosin (H&E) staining revealed reduced neuronal degeneration with fewer microglia in the EEAE-treated group. These findings suggest that the antidiabetic, antioxidant, anti-inflammatory, and neuroprotective effects could be due to the anthocyanins, a bioactive compound in EEAE. Therefore, it can potentially be developed as a natural therapeutic product in improving diabetes-induced cognitive impairment
- PublicationAssessment of cytokine secretions by monocytes in the presence of synovial fluid-derived exosomes(2025-01)Osteoarthritis (OA) is a prevalent degenerative joint disease marked by inflammation and cartilage deterioration. Synovial fluid-derived exosomes are emerging as key modulators in OA pathogenesis, influencing immune responses and cytokine secretion. This study aimed to assess cytokine secretions, specifically soluble intercellular adhesion molecule-1 (sICAM-1), complement component 5a (C5a), and macrophage migration inhibitory factor (MIF), by monocytes in the presence of synovial fluid-derived exosomes. Exosomes were isolated from the synovial fluid of late-stage OA patients through ultracentrifugation and characterised by Western blot and nanoparticle tracking analysis (NTA). Exosome size has been confirmed between 30 to 150 nm by NTA. Additionally, exosomes expressed tetraspanin markers CD9, CD63, CD81, and HSP70 as demonstrated by Western blot. Monocytes isolated from healthy donor peripheral blood, were cultured with exosomes at various ratios (1:10, 1:20, and 1:40) and time points (24 and 48 hours). Cytokine levels were quantified using enzyme-linked immunosorbent assay (ELISA). The results of this study showed that monocyte-exosome interactions influenced cytokine secretion in a time- and dose-dependent manner. sICAM-1 and C5a exhibited a declining trend with prolonged incubation, except at higher exosome concentrations, where C5a secretion was increased. MIF levels peaked after 48 hours, suggesting delayed cytokine induction. These findings highlight the immunomodulatory role of exosomes in OA, providing insight into the inflammatory processes underlying disease progression
- PublicationThe effect of tlr4 agonist (crx-527) on il-10 production in mice immunized with bcg-msp-1c(2025-01)Malaria, caused by the Plasmodium parasite, continues to be a significant global health burden, particularly in regions with limited access to healthcare. Current malaria vaccines face challenges of suboptimal efficacy and logistical barriers for widespread implementation. One promising antigen for malaria vaccine development is the C-terminal region of merozoite surface protein 1 (MSP-1C), a conserved fragment of MSP-1, the major surface protein of Plasmodium merozoites, which is essential for red blood cell invasion and evasion of host immune responses. This study evaluates the impact of the Toll-like receptor 4 (TLR4) agonist CRX-527 on IL-10 production in mice immunized with the BCG-MSP-1C vaccine, developed in our laboratory by cloning the MSP-1C antigen with the Bacillus Calmette–Guérin (BCG) vaccine, which is primarily used for tuberculosis (TB) prevention. Treatment groups included PBS-T80, LPS, BCG, and BCG-MSP-1C. The results revealed a significant enhancement of IL-10 production across all groups in both liver and lymph node supernatant samples in the presence of CRX-527. Among these, the BCG-MSP-1C group exhibited the highest IL-10 levels, followed by the BCG, LPS, and PBS-T80 groups. IL-10, an anti-inflammatory cytokine, plays a pivotal role in regulating the immune response, ensuring controlled infection management while minimizing tissue damage. These findings highlight CRX-527’s potential as an effective immune-modulatory adjuvant for malaria vaccine strategies. The incorporation of CRX-527 with the BCG-MSP-1C vaccine offers a dual immunization approach, enabling protection against both malaria and tuberculosis with a single immunization. This strategy could significantly reduce the burden of multiple vaccine doses and improve immunization coverage in resource-limited settings. The study underscores the potential of CRX-527 to enhance vaccine efficacy and promote long-term immunity, supporting its role in advancing cost-effective, dual-purpose vaccine solutions for endemic regions
- PublicationDetermination of total immunoglobulin g and immunoglobulin g subclass response against sars-cov-2 omicron variant in pfizer and sinovac vaccinated serum samples(2025-01)The COVID-19 pandemic, caused by the highly transmissible SARS-CoV-2 virus, continues to pose significant global health challenges. The emergence of variants such as Omicron has raised concerns regarding immune escape, waning immunity, and the long-term effectiveness of COVID-19 vaccines. While vaccination remains the most effective strategy in mitigating severe disease and transmission, differences in immune responses elicited by various vaccine platforms necessitate further investigation. This study aimed to evaluate the humoral immune response, focusing on total Immunoglobulin G (IgG) levels and IgG subclasses (IgG1 and IgG4), in individuals vaccinated with Pfizer-BioNTech (BNT162b2) and Sinovac (CoronaVac) vaccines. A total of 14 participants were recruited, with seven receiving Pfizer and seven receiving Sinovac. Serum samples were collected at six critical time points: pre-vaccination, post-first dose, two weeks after the second dose, and post-booster doses at two, 26, and 52 weeks. An indirect enzyme-linked immunosorbent assay (ELISA) was employed to quantify spike-specific IgG responses. The results demonstrated a significant increase in total IgG levels over time in both vaccine groups (p < 0.0001). Sinovac recipients exhibited higher total IgG levels (predicted mean: 1.984) compared to Pfizer recipients (predicted mean: 1.442). IgG1 levels remained comparable between both groups across all time points (p > 0.05), with Sinovac showing a transiently higher IgG1 response at two- and 26-weeks post-booster. In contrast, IgG4 levels significantly increased in Pfizer recipients at later booster time points (26 and 52 weeks, p < 0.05), whereas Sinovac elicited a less pronounced IgG4 response. These findings suggest that Sinovac induces a stronger early total IgG response, while Pfizer leads to a more pronounced IgG4 response after booster doses. The distinct patterns of IgG subclass distribution may influence long-term immunity and immune regulation following vaccination. Understanding these differential immune responses is essential for optimizing booster strategies, refining vaccine policies, and ensuring prolonged protection against emerging SARS-CoV-2 variants
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- ItemElectrical Parameters Determination For Shallow Subsurface Using 2-D Resistivity Imaging And Ground Penetrating Radar(Universiti Sains Malaysia, 2017-08)Electrical parameters can be obtained using 2-D resistivity imaging and Ground Penetrating Radar (GPR) methods. 2-D resistivity imaging method measures directly the parameter but calculations are needed for GPR method as the method only provide image of the subsurface. This research aims to determine electrical parameters for shallow subsurface using 2-D resistivity imaging and Ground Penetrating Radar (GPR) methods and to validate electrical parameters related to resistivity, ρ and frequency-dependent conductivity, σ using the two methods. The research also aims to determine the correlation between electrical parameters for horizontal and vertical resolution and establish Frequency-dependent Electrical Parameters worksheet. A borehole was drilled in USM and two boreholes in Sungai Batu for verification. Frequency-dependent conductivity values representing GPR method were calculated using two equations. The first equation is suitable for media that is not influenced by relative dielectric permeability while the second equation is suitable for low-loss dielectric medium. Mean absolute percentage errors (MAPE) for both equations are calculated to determine the efficiency in correlating electrical parameters. USM (weathered granite) has conductivity and resistivity values of 0.41 – 3.03 mS/m and 330 – 2425 Ωm respectively with N-value of 6 – 10. Tupah (weathered granite) display conductivity and resistivity values of 0.09 – 1.38 mS/m and 724 – 10994 Ωm respectively. The conductivity and resistivity values in Bukit Jambul (granitic rock) are 0.13 – 0.25 mS/m and 3999 – 7743 Ωm. Conductivity and resistivity values of Sungai Batu (sedimentation from fluvial system) are 1.2 – 189.18 mS/m and 5 – 878 Ωm with N-value of 7 – 20. Bukit Kalong (weathered limestone) exhibits values of 9.24 – 29.94 mS/m and 33 – 109 Ωm. The electrical parameters for shallow subsurface in all study areas are successfully determined through direct measurement and calculations. The validation of electrical parameters from 2-D resistivity imaging and GPR methods indicate that the values between measured and calculated are in range and correspond well. The correlation of electrical parameters is effective for horizontal and vertical resolution for most of the study areas indicated by low MAPE values. The MAPE for both equations in all study areas are < 5 % except in Sungai Batu. The first equation obtained MAPE > 5 % in Sungai Batu due to high radar energy attenuation value that largely influence the equation. The research is able to establish Frequency-dependent Electrical Parameters worksheet that can be used to calculate electrical parameters for GPR with the aid from 2-D resistivity imaging method.
- PublicationION exchange equilibria of Copper (II), Nickel (II) and Manganese (II) on the Amberlite IRC 748 ION Exchange Resin(2009-05-01)Malaco Copper Mine at Mengapor, Pahang is planning to treat their low grade copper ores using heap leaching technique. Unfortunately, the pregnant leach solution produced from this leaching is believed to contain impurities which is manganese, nickel, iron and zinc. Therefore, a simulation of this problem is developed by treating the synthetic copper(II), nickel(II) and manganese(II) aqueous solution with selected chelating ion exchange resin Amberlite IRC 748 which has iminodiacetic (IDA) functional group. The results showed that the maximum loading of copper(II) obtained is 47.50 g/l, while maximum loading for nickel(II) and manganese(II) is 2.50 g/l and 10 g/l respectively. Besides, the equilibrium data obtained is better fitted to Langmuir isotherm model. Throughout this study, conclusion could be made that among of these three metal ions, copper is highly selective towards the selected resin.
- ItemPeperiksaan Perkhidmatan Pembantu Tadbir (Kewangan) W19 Kertas I – Umum 30 April 2019(Universiti Sains Malaysia, 2019-04-30)Tarikh : 30 April 2019 (Selasa) Masa : 9.00 pagi – 11.00 pagi (2 jam) Tempat : Kampus Induk
- PublicationAnalisis Sirah Nabi Saw Dalam Buku Teks Pendidikan Islam Tingkatan Satu Di Malaysia Berdasarkan Manhaj Al-muḥaddithīn(2024-09)Visual dialogue dataset, i.e. VisDial v1.0 includes a wide range of Microsoft Common Objects in Context (MSCOCO) image contents and collected questions via a crowdsourcing marketplace platform (i.e. Amazon Mechanical Turk). The use of existing question history and images no longer contributes to a better understanding of the image context as they do not cover the entire image semantic context. This research proposes the DsDial dataset, which is a context-aware visual dialogue that groups all relevant dialogue histories extracted based on their respective MSCOCO image categories. This research also exploits the overlapping visual context between images via adaptive relevant dialogue history selection during new dataset generation based on the groups of all relevant dialogue histories. It is half of 2.6 million question-answer pairs. Meanwhile, this research proposes Diverse History-Dialog (DS-Dialog) to resolve the missing visual semantic information for each image via context-aware visual attention. The context-aware visual attention includes the question-guided and relevant-dialoguehistory- guided visual attention modules to get the relevant visual context when both have achieved great confidence. The qualitative and quantitative experimental results on the VisDial v1.0 and DsDial datasets demonstrate that the proposed DS-Dialog not only outperforms the existing methods, but also achieves a competitive results by contributing to a better visual semantic extraction. DsDial dataset has proven its significance on LF model as compared to VisDal v1.0. Overall quantitative results show that DS-Dialog with DsDial dataset has achieved the best test scores for recall@1, recall@5, recall@10, mean rank, MRR, and NDCG respectively.
- PublicationModelling of biochemical oxygen demand, chemical oxygen demand and ammoniacal nitrogen for sungai perai basin using hydrodynamic model(2023-05-01)Shortage of clean water has been an issue for an urbanised areas. To overcome the problem, Pulau Pinang tries to find an alternative source of water; and one of the options is Sungai Perai. The river has a large catchment area and is located in Pulau Pinang state boundary however the river was polluted and not suitable to be extracted for domestic consumption. To understand the behaviour of the river, a water quality model was developed for Sungai Perai, Sungai Jarak and Sungai Kulim using InfoWork ICM. Rainfall data and topographical information were use for hydrological analysis; while sampling and demographical information as pollution input for the water quality model. Year 2016 was selected as model event due to data availability. The result of three parameters (BOD, COD and NH4) was used for analysis and TMDL calculation; load duration curve approach was used to estimate TMDL. Based on the analysis, it was observed the concentration of pollutants is highest in March and lowest in November. The concentration was observed to be in relation to seasonal change; as the flow increased, the concentration decreased. The simulation data was used to generate TMDL. It was discovered that pollutant load exceedance about 95% which is the highest during the rainy season and the problematic pollutant is NH4.