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- PublicationThe screening of alpinia purpurata ethanol extract for selective anticancer activity in vitro(2025-01)Cancer, including breast, cervical, and brain cancers, remains a major health challenge globally, requiring effective treatments. This study investigates the cytotoxic effects of Alpinia purpurata ethanol extract and tamoxifen on HeLa, MCF-7, DTBRG, and Vero cells using the MTT assay and qualitative phytochemical tests to evaluate their potential as anticancer agents. The results revealed that the A. purpurata ethanol extract exhibited significant cytotoxicity, with IC50 values of 18.19±1.5 μg/mL for HeLa, 158.70±1.1 μg/mL for MCF-7, 68.47±1.7 μg/mL for DTBRG, and 3.31±2.5 μg/mL for Vero cells. Tamoxifen, a well-established anticancer drug, demonstrated stronger cytotoxic effects, with IC50 values of 0.13±0.5 μg/mL for HeLa and 1.61±0.7 μg/mL for MCF-7 cells. However, tamoxifen exhibited higher toxicity to normal cells. In conclusion, Alpinia purpurata ethanol extract shows promising anticancer activity with selective toxicity towards cancerous cells, suggesting its potential for development as a safer alternative to tamoxifen
- PublicationCytotoxicity study on the combination of cisplatin and gallic acid on cervical cancer cells (hela)(2025-01)Cervical cancer is the fourth most common cancer among women worldwide and remains a major health concern. Cisplatin, a chemotherapeutic agent, is often limited by severe side effects and the development of resistance. Combining cisplatin with natural compounds, such as gallic acid, may enhance therapeutic efficacy while reducing toxicity. This study aimed to evaluate the cytotoxic and anti-migratory effects of cisplatin combined with gallic acid on cervical cancer cells (HeLa). Cytotoxicity was assessed using the MTT assay the half-maximal inhibitory concentration (IC50). Serial dilution of cisplatin, starting from its IC50 was combined with a fixed concentration of gallic acid at its IC50. The combination effects were analyzed using CompuSyn software to assess potential synergy, additivity, or antagonism. The combination with the greatest synergistic effect was then chosen for wound healing assay, to examine the anti-migratory effects of the combination. The IC50 of cisplatin and gallic acid for HeLa cells were 25.12 μg/mL and 85.70 μg/mL, after 24 hours, which decreased to 1.786 μg/mL and 13.27 μg/mL at 48 hours. For WRL-68 cells, the IC50 values of cisplatin and gallic acid were 28.02 μg/mL and >100 μg/mL at 24 hours, decreasing to 8.842 μg/mL and 21.06 μg/mL at 48 hours. All combinations of cisplatin and gallic acid significantly inhibited HeLa cell proliferation with combination index values below 1, indicating a synergistic effect. Furthermore, the combination exhibited anti-migratory effects, showing the lowest percentage of wound closure compared to control and single treatment groups. These findings suggest that combining cisplatin with gallic acid holds potential as a novel therapeutic strategy to enhance cervical cancer treatment outcomes
- PublicationInvestigation of exon 12 mutations in the janus kinase 2 (jak 2) gene among polycythemia vera patients from Hospital Pakar Universiti Sains Malaysia(2025-01)Polycythemia vera (PV) is a myeloproliferative disorder characterized by excessive red blood cell production. While JAK2 V617F mutations have been extensively studied, mutations in JAK2 exon 12 remain under-explored. This study aimed to determine the prevalence of JAK2 exon 12 mutations among PV patients at Hospital Pakar Universiti Sains Malaysia (HPUSM) and explore their associations with clinical and hematological parameters. A total of 86 PV patients were screened for JAK2 exon 12 mutations using polymerase chain reaction (PCR) followed by Sanger sequencing. Patients were categorized into groups based on the presence of JAK2 exon 12 mutations, JAK2 V617F mutations, both mutations, or neither. Clinical data, including age, gender, splenomegaly, and thrombosis, were obtained from medical records. Hematological parameters, such as hemoglobin, hematocrit, white blood cell (WBC) count, platelet count, and lactate dehydrogenase (LDH), were analyzed. Fifteen patients tested positive for JAK2 exon 12 mutations, revealing two mutation types such as insertion mutations and point mutations. Interestingly, co-occurrence of JAK2 V617F and exon 12 mutations was found in eight patients (9.32%), indicating the potential for complex genetic mechanisms. Patients with both JAK2 V617F and exon 12 mutations had the highest mean age and elevated platelet and WBC counts, indicating a more aggressive disease course. JAK2 V617F mutations were associated with higher rates of thrombosis and splenomegaly compared to exon 12-only mutations. Morphological analysis revealed hypercellularity in the bone marrow of JAK2 exon 12-positive patients, with significant erythroid and megakaryocytic proliferation. This study underscores the clinical significance of JAK2 exon 12 mutations, highlighting their distinct impact on disease progression and clinical features compared to JAK2 V617F mutations
- PublicationInsights into the interaction between statins and monocarboxylate transporter 1: a molecular docking approachl(2025-01)Statins are commonly prescribed in the management of cardiovascular diseases; however, they can lead to statin-associated muscle symptoms (SAMS), which are often related to mitochondrial dysfunction. Monocarboxylate transporter (MCT1) is a proton-linked monocarboxylate transporter that facilitates the cellular uptake of statins, influencing their pharmacokinetics and potential effects on cellular metabolism and mitochondrial function. Although direct interactions between statins and MCT1 are not well-documented, emerging evidence suggests that mitochondrial dysfunction associated with statins may involve MCT1-mediated mechanisms, potentially through alterations in lactate transport and metabolic regulation.. This study explores the molecular interactions between statins and MCT1, focusing on their binding affinities and the subsequent effects on mitochondrial function and gene regulation. The 3D structure of MCT1 from Rattus norvegicus was modeled using the Swiss-Model database, based on similar sequences from Mus musculus. Molecular docking analyses, employing both blind and specific docking methods, indicated that atorvastatin lactone had the highest binding affinity to MCT1 (-8.7 kcal/mol and -9.2 kcal/mol, respectively), followed by rosuvastatin lactone (-7.5 kcal/mol and -7.9 kcal/mol), simvastatin lactone (-7.7 kcal/mol for both), pravastatin lactone (-7.4 kcal/mol for both), and simvastatin acid (-5.7 kcal/mol and -6.0 kcal/mol). Of all statins analyzed, simvastatin acid does not have any hydrogen bonds with amino acid residues of MCT1 thus could explained its lowest binding affinity. It unlike other statins. Important binding residues, including LEU132, TYR70, and THR388, were identified as essential for ligand interactions. By identifying the key molecular interactions that contribute to SAMS, this study establishes a solid framework for early prediction of MCT1 involvement during the pathology process
- PublicationElucidating the role of dendritic cells and b cells in imiquimod (IMQ)-induced psoriasis-like mouse model(2025-08)Psoriasis is a chronic inflammatory skin disorder characterised by keratinocyte hyperproliferation and immune dysregulation. Although psoriasis is a T cell-mediated disease, increasing evidence suggests the important roles of dendritic cells (DCs) and B cells in initiating, sustaining and regulating psoriatic inflammation. Therefore, this study aims to elucidate the roles of DCs and B cells in an imiquimod (IMQ)-induced psoriasis-like mouse model through a time-based analysis of immune responses in the skin, spleen and blood. BALB/c mice were divided into control (n=6) and IMQ-induced (n=6) groups, with samples collected on day 3, day 5 and day 7. Psoriasis-like inflammation was induced via topical IMQ application, leading to increased skinfold thickness, modified Psoriasis Area and Severity Index (PASI) scores and splenomegaly compared to controls. Histological analysis (hematoxylin and eosin (H&E) and Masson’s trichrome staining) revealed hallmark psoriasis features, including epidermal hyperplasia, hyperkeratosis, immune cell infiltration and visible blood vessel observation, as well as increased immune cell density in the spleen. Notably, the white pulp of the spleen exhibited significant germinal centre (GC) enlargement, indicating heightened lymphoid activity. Flow cytometry was used to analyse DC and B cell dynamics across samples. The results demonstrated an increasing trend in CD11chi/+MHCII+ DC populations across all samples, accentuating their involvement in antigen presentation and immune activation. Concurrently, B220+CD38+ B cells increased in the spleen, while CD19+CD38+ B cells were significantly higher in the skin but decreased in the blood, suggesting distinct migration and activation dynamics. Subsequent gene expression analysis (RT-PCR) of CD11c, H2-Aa, BAFF, IL-10, IL-6 and CXCR5 revealed consistent upregulation in the IMQ-induced group, supporting a sustained inflammatory state driven by DC and B cell activation. ELISA-based cytokine analysis showed elevated serum levels of BAFF, IL-10 and IL-6 at each time point, further reinforcing their role in chronic inflammation and B cell activation. Overall, the increment of DC and B cell markers at both cellular and molecular levels, accompanied by elevated pro- and anti-inflammatory cytokines, reflects a robust and evolving immune response. These findings affirm the successful establishment of the IMQ-induced psoriasis-like mouse model and support the study objectives in elucidating the dynamic involvement of DCs and B cells during disease progression as well as offering a foundation for future therapeutic research
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- ItemProperties Of Recycled Crosslink Polyethylene Filled High Density Polyethylene Composites(Universiti Sains Malaysia, 2013-07)Waste crosslinked polyethylene (XLPE) obtained from a high voltage electric cable was directly utilized, recycled and incorporated into a high density polyethylene matrix. Due to the high gel content (93%), the possibility of producing a completely miscible blend is quite unlikely. However due to that factor, the waste is break down into small filler. They are then compounded with HDPE in concentrations of 5, 10, 15, 20 and 30wt% to produce a composite material. The tensile properties, DSC and morphology of the composite were obtained. However, addition of the waste did not give any reinforcing properties to HDPE matrix. This is visible from the tensile properties of the composite where the tensile strength decreases as the waste concentration increase from 5, 10, 15, 20 and 30%. The elongation at break of the composite decreases as the waste concentration increases from 5, 10, 15, 20 and 30%. The chemical resistance test was done to obtain the tensile properties of before and after immersion. The two chemicals selected are nitric acid and ammonium hydroxide. The tensile strength of the composite decreased compared to virgin HDPE samples. Chemical resistance properties show that overall the tensile strength of the composite decreases with increasing waste concentration from 5, 10, 15, 20 and 30% with chemical concentration of 50 and 100%. For elongation at break of the composite, the value shows irregularity for different waste concentration. Different heating rates of 5, 10 and15°C/min of the DSC scans shows co-crystalization with increasing waste content form 5, 10, 15, 20 and 30%.
- PublicationRational Design And Synthesis Of Peptide Inhibitors Of Ns2b/Ns3 Protease As Therapeutic Agents For Dengue Virus Type 2(2021-10)The main objectives of this study are to design potent and selective peptide inhibitors by studying the interactions between the designed peptides and the NS2B/NS3 dengue protease using two independent docking programs (MOE and AutoDock4.2), thus, to evaluate the quantitative and qualitative docking results from both programs. The other objectives are to synthesize and characterize the potential peptides by using Fmoc Solid Phase Peptide Synthesis (SPPS) technique, to perform NS2B/NS3 dengue protease expression and purification, and finally to investigate the biological evaluation of the selected peptides using in vitro NS2B/NS3 dengue protease inhibition assay.
- ItemDesign And Development Of Robot End-Effector For The Use In Lower-Limb Stroke Rehabilitation Exercises(Universiti Sains Malaysia, 2022-07-25)Stroke is the second largest cause of human death worldwide and is also a major cause of long-term disability such as walking gait abnormalities. Rehabilitation is essential in helping patients regain as much motor function as possible. Robot assisted rehabilitation is currently the forefront in this regard. However, no solutions are currently widely available for use in developing countries like Malaysia. Therefore, there is space for such a product to be developed and commercialized. Thus, a smart lower-limb end-effector prototype that can be installed on a collaborative robot to aid patients performing exercises such as plantarflexion, dorsiflexion, hip abduction and hip adduction was developed. The project kick started by designing the end effector as four different parts on in Solidwork. This step is then followed by slicing process using Ultimaker Cura and then 3D printing. The 3D printed is then assembled up and tested for strength and design accuracy. At this stage, any design failure is then followed by redesigning and 3D printing again. Meanwhile, MPU6050 sensor was coded using Arduino Uno and powered by NodeMcu. This set up was placed on the foot holder to measure the rehabilitation angle. The sensor is also connected any app which was developed using Blynk to showcase the data obtained in terms of angle X˚, Y˚ and Z˚ Then, two healthy subjects, a male and female were choosen to carry out all four type of exercises mentioned above. The results obtained shows that angle recorded falls within the range of a human to carry out those exercise (20-35° of dorsiflexion, 15-30° of plantarflexion, 30–55° of hip abduction and 15–30° of hip adduction). This shows that the end effector perms well and can be used to aid physiotherapist and the patient. Therefore, a smart lower-limb end-effector prototype that can be installed on a collaborative robot to aid patients performing various leg exercises has been successfully created which also incooperates IoT elements.
- ItemRemaining competitive in China: a case study of ACIC's business model on work-integrated -learning(2010-10)This case study explores the strategy engaged by Australia China Investment Corporation (ACIC), taking into account the effects of globalization and the emerging-economy environment of the People’s Republic of China (PRC). ACIC’s business model is based on Work-Integrated-Learning. The Company’s flagship programme, Study Abroad Internship Programme, is chosen as the study object. This case study aims to confirm if the current strategy employed by the company is applicable to remain competitive in the PRC market and further find out the effects of these strategies. The country analysis conducted is PESTLE, based on the framework of Global Competitive Index. SWOT analysis, TOWS matrix with attributes of Balanced Scorecard, and Quality Function Deployment (QFD) concepts together with Sun Tzu Art of Strategy are employed as analysis techniques. It is found that ACIC is employing a combination of strategies and has managed to remain competitive in PRC with an increasing revenue trend. The company focuses on learning and growth as well as its internal processes. Intelligence and information is its utmost priority while positioning, targeting, strength and weakness estimation are also regarded as important. The case study results, while answering the research questions, have also encourage a paradigm shift on defining global business strategy, especially in the dynamic emerging economy of PRC.
- ItemRenal survival and its prognostic factors in chronic kidney disease patients in Hospital Universiti Sains Malaysia, Kelantan(Pusat Pengajian Sains Perubatan, Universiti Sains Malaysia, 2016-04)Introduction: End Stage of Renal Disease (ESRD) in Chronic Kidney Disease (CKD) patients represents a heavy burden for patients, families, and health care systems. Objectives: The objectives of this study were to determine the renal survival time of CKD patients at Hospital USM and to identify the prognostic factors that influence the renal survival of patients. Methodology: A retrospective cohort study was conducted involving 247 CKD patients at Hospital USM, Kelantan from January 2005 until December 2015. All patients who fulfilled the criteria were included in the study. The medical record were reviewed and the renal survival time based on the time of the first date of diagnosis with CKD until the the first date of diagnosis with ESRD or received dialysis. The Kaplan-Meier and Cox proportional hazard regression analyses were used in the statistical analysis. Results: Overall renal survival time of CKD patients was 26 months. The significant prognostic factors that influence the renal survival of CKD patients were GFR (adjusted hazard ratio (HR)=0.96, 95% confidence interval (CI): 0.98,0.99; p value <0.001), smoking status (adjusted HR=2.19, 95% CI: 1.53, 3.13; p value=0.042), comorbid hyperlipidemia (adjusted HR=1.87, 95% CI: 1.34,2.60; p value =0.005), analgesics (adjusted HR=1.87, 95% CI: 1.21,2.88; p value =0.015), functional GI disorder (adjusted HR=1.42, 95% CI:1.07,2.01; p value =0.016), lipid lowering agents (adjusted HR=1.41, 95% CI: 1.02,1.97; p value=0.039), corticosteroid (adjusted HR=2.10, 95% CI: 1.25,3.55; p value =0.005), urea (adjusted HR=1.03, 95% CI: 1.01,1.05; p value <0.001), and creatinine (adjusted HR=0.99, 95% CI: 0.98,1.00; p value =0.005). Conclusion: The medium renal survival time of CKD patients in this study very fast within 26 month. The prognostic factors of renal survival identified were GFR level, smoking status, comorbid hyperlipidemia, analgesics, lipid lowering agents, functional GI disorder, corticosteroid drugs, urea and creatinine are significant to renal survival among CKD patients in Hospital USM. Thus, the clinician can change the clinical management by focus on the factors and slow the progression to ESRD.