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- PublicationCardioprotective effects of bunga kantan (etlingera elatior) in hypercholesterolaemic myocardial infarction sprague dawley rats(2025-01)Cardiovascular diseases (CVDs), especially myocardial infarction (MI), remain a global health challenge with high mortality rates. Despite advancements in surgical and pharmacological interventions, the prevalence of MI continues to rise, often linked to risk factors such as hypercholesterolaemia. Alternative therapies utilising natural compounds with cardioprotective properties offer a promising alternative for addressing these limitations. This study investigates the potential of Etlingera elatior aqueous extract (EEAE) as a preventive treatment against hypercholesterolaemia-induced MI. The research employed a high-cholesterol diet (HCD) to induce hypercholesterolaemia in male Sprague-Dawley rats, followed by isoprenaline administration to induce MI. Rats treated with EEAE at 1000 mg/kg were evaluated over 12 weeks. Parameters, including blood pressure and cholesterol levels, were taken. Histopathological analyses were conducted to observe structural improvements in the myocardium. Results demonstrated that EEAE had no significant effect in lowering cholesterol levels and blood pressure but showed capability in preserving cardiac integrity. EEAE-treated groups exhibited enhanced histological recovery compared to untreated controls. These findings suggest that EEAE holds potential as a natural therapeutic agent for preventing MI in hypercholesterolemic conditions. Further research is needed to explore its mechanisms and applicability in clinical settings
- PublicationUnderstanding the role of nnav1.5 in breast cancer via sirna approach(2025-02)Neonatal Nav1.5 (nNav1.5) plays a crucial role in the development and spread of breast cancer. This work highlights its potential as a biomarker and treatment target. The hallmarks of breast cancer, a cancer that is common around the world, are unchecked cell growth and metastasis. Targeted therapies are needed since metastasis is responsible for around 90% of cancer-related fatalities, despite the advancements in early identification and therapy. The study explored the molecular mechanisms underlying nNav1.5's role in the invasive property of breast cancer. In MDA-MB-231 cells, siRNA-mediated knockdown was used to assess its effect of nNav1.5 mRNA expression and metastatic behaviour, cell motility. Previous research results showed that nNav1.5 is substantially overexpressed in metastatic breast cancer cells relative to non-metastatic cells, which is associated with increased invasive and migratory capabilities. In this study, the potential role of nNav1.5 in the development of metastases was further supported by the significant decrease in cancer cell motility which siRNA-mediated silencing of nNav1.5. This study also supports nNav1.5 expression as a useful prognostic indicator for aggressive breast cancer subtypes, the triple-negative breast cancer. A solid basis for future research aiming at incorporating nNav1.5-targeted tactics into precision medicine frameworks is established by this work, which also contributes to our understanding of metastatic biology. These results could greatly improve patient survival and breast cancer care by tackling the crucial problem of metastasis
- PublicationDetermination of humoral immune response in mice immunised with milk expressing three-tb epitopes(2025-01)Tuberculosis (TB) continues to pose significant global health challenges despite the widespread use of the Bacillus Calmette-Guérin (BCG) vaccine. However, its limitations in inducing robust mucosal immunity, especially in adults, necessitate alternative approaches. This study explores the potential of a novel oral vaccine utilizing milk containing multi-epitope TB antigens. This study investigates the humoral immune response elicited in Balb/c mice immunized with milk containing multi-epitope tuberculosis antigens. These antigens which are Ag85B, Acr, and RpfE were expressed in goat milk with a secretory IgA fusion construct designed to produce milk containing multi-epitope TB:IgA to enhance mucosal immunity. The mices were immunized with five treatment groups which are Milk Daily (MD), Normal Milk (NM), BCG only (BCG-O), BCG + Milk Daily (BCG-MD), and BCG + Normal Milk (BCG-NM) to assess immune responses against three Mycobacterium tuberculosis epitopes. Two weeks post-immunization, serum, saliva, and BAL fluid samples were collected for analysis. ELISA plates were coated with the respective antigens to measure antigen-specific IgA and IgG levels. Optical density (OD) readings were used to quantify immune responses, and statistical analysis was conducted to determine significant differences between treatment groups. The immunized mice groups, including BCG and milk combinations, demonstrated varying levels of systemic IgG and mucosal IgA antibodies in serum, saliva, and bronchoalveolar lavage samples. Among the treatment groups, the milk-based vaccine candidate elicited robust antigen-specific IgG and IgA responses, indicating its potential for providing targeted immunity. These findings indicate the vaccine's potential to address key challenges of TB prevention, particularly in targeting mucosal surfaces which is the primary site of Mycobacterium tuberculosis infection. This study highlights the promise of oral mucosal vaccines as a complementary or alternative strategy to intradermal BCG vaccination, aiming to enhance protection and control TB more effectively. Future research and clinical trials are needed to validate these findings and further optimize this innovative vaccine approach
- PublicationExpression of sars-cov-2 k51a/s54a nsp7 protein in escherichia coli c41(de3) and escherichia coli bl21(de3)(2025-01)Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) relies on the RNA-dependent RNA polymerase (RdRp) complex, comprising NSP7, NSP8, and NSP12, for replication and transcription. Mutations in NSP7, such as K51A and S54A, disrupt interactions with NSP8 and NSP12, impairing polymerase activity and structural integrity. These mutations offer insights into the development of antiviral therapeutics targeting the RdRp complex. This study aimed to express the mutant K51A/S54A NSP7 protein in Escherichia coli C41(DE3) and BL21(DE3) using the pET-15(b) vector. The methodologies included the preparation of the pET-15(b)-mutant NSP7 plasmid construct, transformation of the plasmid into E. coli, and optimization of protein expression. Parameters such as IPTG concentrations (0–1.0 mM) and different host strains were systematically optimized. The mutant NSP7 (K51A/S54A) protein was successfully expressed in both E. coli strains, with SDS-PAGE revealing distinct bands at the expected molecular weight. Optimal protein expression was achieved at 0.5 mM IPTG concentration. The findings highlighted differences in expression efficiency between E. coli C41(DE3) and E. coli BL21(DE3), with E. coli BL21(DE3) yielding higher expression levels. This research contributes to the understanding of SARS-CoV-2 replication by providing optimized conditions for expressing K51A/S54A NSP7 protein, enabling functional and structural studies. The findings offer a foundation for exploring NSP7 mutations as therapeutic targets and demonstrate the utility of bacterial systems for producing viral proteins in high yield, potentially accelerating antiviral drug discovery
- PublicationEvaluation of phytochemicals, antioxidant & antimicrobial properties of cinnamomum verum extracts(2025-01)Traditional medicine has long relied on plant-based remedies to address various health issues, with cinnamon bark being widely recognized for its therapeutic properties. This study aims to investigate the phytochemical, antioxidant and antimicrobial properties of cinnamon extracts, emphasizing its potential as a natural therapeutic agent. Aqueous extract of C. verum (AECV) and ethanolic extract of C. verum (EECV) were analyzed for their bioactive compounds, revealing the presence of alkaloids, phenols, flavonoids, tannins, glycosides, and terpenoids, while saponins were detected only in AECV. Antioxidant activity was assessed using DPPH radical scavenging and total phenolic content (TPC) assays. AECV demonstrated higher antioxidant potential (IC50 = 0.233 mg/mL) than EECV (IC50 = 0.418 mg/mL), although both exhibited lower activity compared to ascorbic acid (AA) (IC50 = 0.00673 mg/mL). TPC analysis revealed that EECV (0.1001 [0.236] mg GAE/g) showed higher phenolic content than AECV (0.0227 [0.036] mg GAE/g), indicating ethanol's effectiveness in extracting phenolics. Antimicrobial activity against S. aureus and E. coli was evaluated using minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays, where AECV demonstrated limited antibacterial activity against S. aureus (MIC = 20 mg/mL), while EECV exhibited no significant effects. Neither extract inhibited E. coli, likely due to insufficient extract concentrations. These findings indicate that cinnamon bark showed potential as a natural source of antioxidant, while further investigation is needed to explore its antimicrobial potential
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- PublicationCharacterisation And Formulation Of Topical Methyl Salicylate Patches: Effect Of Solvents On Adhesion And Drug Permeation(2023-01)Topical methyl salicylate (MS) patch is popular for pain management. The skin permeation profile of MS is important for formulation design but limited studies were conducted. This project aims to investigate the effect of solvents on the characteristics of patches, drug release and permeation of MS. In this project, suitable solvents were first selected for the patch formulation. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy was utilised to scan the stratum corneum (SC) sheets treated with solvents and MS. Next, in vitro permeation studies were carried out with 10%v/v of MS in solvents. After that, patches containing 5%w/w of solvents and/or 10%w/w of MS were prepared with Durabond PC 1879A (8%w/w), Nikasol TS-620 (7%w/w), carboxymethyl cellulose (3.5%w/w) and polyvinyl pyrrolidone (3%w/w). Next, the patches formed were subjected to physiochemical characterisation tests, including ATR-FTIR spectroscopy, tackiness test using stainless-steel probe, peel strength test with porcine ear skin, swelling test, in vitro drug release and skin permeation studies. In in vitro permeation studies, MS in propylene glycol (PG) in drug solution displayed the highest skin permeation of MS and followed by Plurol® oleique (PLU), Labrasol® (LA), Transcutol® (TRC), Maisine® (MAI) and isopropyl myristate (IPM) at 24 h.
- ItemORAL BIOA V AILABILITY ENHANCEMENT OF POORLY SOLUBLE AND POORLY PERMEABLE DRUGS USING SELF-MICROEMULSIFYING DRUG DELIVERY SYSTEMS AND THE EFFECT OF PIPERINE(2010-01)There are approximately 40% of new drug molecules discovered and some drug molecules that are available in the market, having poor bioavailability due to poor solubility and/or poor permeability. The present study aimed at formulating a selfmicroemulsifying drug delivery system (SMEDDS) using two BCS class IV drugs, namely sulpiride and norfloxacin. Sulpiride is a P-gp substrate and norfloxacin is a substrate of MRP2, BCRP and an unknown efflux pump. From the solubility studies of drugs in various oils, surfactants and co-surfactants, oleic acid, Tween 80 and propylene glycol were chosen to prepare SMEDDS formulations. Two formulations were chosen for further study based on droplet size and solubility. The first formulation consisted of 4.76% w/w of oleic acid, 63.49% w/w of Tween 80 and 31.7 5% w/w of propylene glycol, with a mean droplet diameter of 9.27 nrn and drug solubility of 22 mg/1000 mg for sulpiride, 9.57 nrn and 17.33 mg/1000 mg for norfloxacin respectively. The other formulation consisted of 17.71% w/w of oleic acid, 55.14% w/w of Tween 80 and 27.15% w/w ofpropylene glycol, with a mean droplet diameter of 85 nrn and drug solubility of 32 mg/1 000 mg for sulpiride, 92 nrn and 27.53 mg/1000 mg for norfloxacin. !socratic HPLC- fluorescence methods were developed and validated for the determination of sulpiride and norfloxacin in rat intestinal perfusates and rabbit plasma separately. The in situ permeability experiment was performed on three intestinal segments, duodenum, jejunum and ileum in rats using single-pass perfusion technique. The SMEDDS formulation and micellar solution exhibited significant increase in the effective permeability XXXIX coefficient of the drug across all the three intestinal segments compared with drug solution for the two drugs. There was no significant difference in the effective permeability coefficients values between SMEDDS formulation and micellar solution for both drugs. When the effect of droplet sizes on jejunum permeability was studied, it was found that there was no significant difference in permeability coefficients with droplet sizes of less than 100 nm. From the in vivo bioavailability study performed in rabbits, it was found that there was a significant decrease in the T max and significant increase in the Cmax and AUC of the SMEDDS formulations when compared with Dogmatil®/Norfloxin® respectively. On the other hand, the rate and extent of absorption of sulpiride/norfloxacin were not significantly affected, when the droplet sizes of less than 100 nm were compared. When the effect of dietary spice piperine on the oral bioavailability of sulpiride/norfloxacin suspension and SMEDDS formulations was evaluated, it was found that concomitant administration of both the drugs with piperine in suspension and SMEDDS formulations significantly enhanced the oral bioavailability of these two drugs. Concomitant administration of piperine with SMEDDS formulation further increased the bioavailability of the drugs. Hence, SMEDDS can be used to increase the bioavailability of poorly soluble and poorly permeable drugs.
- ItemPENGHASILAN SEBATIAN AKTIF BERSIFAT ANTIBIOTIK DARIP ADA BAKTERIA MARIN PSEUDOMONAS DOUDOROFFI ABK37-MM(2003-07)A total of 450 bacterial and 7 fungal isolates were obtained from seawater, marine mud, l:· ~beach sand, floating material and marine macroorganisms collected from 11 sampling F sites around the Penang Island. These marine microorganisms isolates were screened for ·the production of antimicrobially active compound. From 450 bacterial isolates, 71.1% . were pigmented and sample from marine mud produced the highest marine bacterial isolates by 55.6% compared to other samples. Screening for the production of antimicrobial active compound from these bacterial isolates was performed by streaking and submerged culture fermentation techniques using yeast extract medium with half strength artificial seawater produced 3.3% and 47.1% positive isolates respectively, with various strength of antimicrobial activities. From these 47.1% marine bacterial isolates, sample from marine mud and yellow or yellowish pigmented isolates produced the highest potential isolates by 73.6% and 66.0%, respectively. Of the 47.1%, 87.3% isolates produced antibacterial compound, 19.3% isolates produced antifungal compound and 6.1% isolates produced antiyeast compound. Despite this, only 1.9% marine bacterial isolates showed antimicrobial activities against all the 8 test microorganisms. One potential marine bacterial isolate which produced the highest antibiotically active compound was chosen for the optimization of medium and cultural conditions in a shake XX!l nask system and was then identified as Pseudomonas duodoroffi ABK37-MM. The optimized medium for the production of antibiotically active compound against the test bacteria, Staphylococcus aureus was 1/8 diluted yeast extract medium ~~th half strength artificial seawater. The optimized medium compositions (%; w/v) were 0.06 maltose, . 0.06 yeast ext-act, 0.145 malt extract and 0.4 L-histidine. The optimized artificial ,. seawater compositions (%; w/v) were 1.8 NaCl , 0.5 MgCb.6H20, 0.1 CaCb,2H20, 0.1 r,KCI, 0.1 KBr, 0.2 Na2S04 and 0.05 NaHC03. The optimized cultural conditions for the ·production of antibiotically active compound were at an initial medium pH of 7.4, agitation rate of 140 rpm, incubation at room temperature (30±2°C), inoculum size of 6% and the volume of medium to the volume of flask ratio at 0.5. The production of antibiotically active compound increased by 37.0% with 14.3% faster than before optimization in a shake flask system .. Medium compositions, buffer concentration and a few physical parameters were reoptimized in the tubular air lift fermenter. The optimized medium (%; w/v) were 0.08 maltose, 0.08 yeast extract, 0.145 malt extract and 0.4 Lhistidine with 0.1 NaHC03. The optimized physical parameters were 1.5 vvm rate of aeration, inoculum size of 8% and the volume of medium to the volume of fermenter ratio of 0.75. Optimization at the fermenter level increased the production of antibiotically active compound by 26.0% at the same production time after optimization at the shake flask level, that was at 144 hours of cultivation. In general, there was an increase of about 72.6% in the production of antibiotically compound after optimization at a fermenter level compared to shake flask system. XX Ill Partial purification of the antibiotically active compound with sephadex G-1 00 gel filtration chromatography produced 9.2 folds of purity with specific antibiotically active compound of 1148.2 U/mg protein. Determination of molecular weigh!_ was done using SDS-PAGE and was estimated about 39 kD compared to known low molecular weight protein. Determination of protein compound and reducing sugar in the compound were 4.9 mg/ml and 0.02 mg/ml, respectively. The antibiotically active compound was found stable at and below of room temperature (30±2°C) and was fully deactivated at the temperature of 40°C. This compound was also found stable at pH range of 6 to 8 and fully deactivated by proteolytic enzyme suggesting that the major part of the compound was protein or protein moiety. TEM studies on the effects of the antibacterial compound on the test bacterial cell, Staphylococcus aureus revealed a chain reaction that occurred at the cell wall and cell membrane leading to cell lysis compared to untreated cell. The frequency and magnitude of the cell wall and cell membrane bleb bing and fragmentation of the test bacterial cell increased with the prolonged of exposure time to antibacterial compound, and it seems to produced pores in the bilayer cell wall leading to cell lysis.
- ItemEnhanced Image Processing Techniques Based On Technical Challenges Of Mammogram Image Characteristics(Universiti Sains Malaysia, 2010-04)Breast cancer is the leading type of cancer in Malaysia. More than 30% of total cancer case reported among women in Malaysia is made up of breast cancer. At the moment, one of the best known techniques used for breast cancer detection is mammography. Unfortunately, the image produced through mammography is normally noisy and low in contrast making detection of early signs of breast cancer (i.e. microcalcification and mass) difficult. Therefore, a lot of studies have been conducted to develop image processing techniques which would help in the detection of these early signs. However, most of these techniques were developed without a thorough study upon the mammogram image technical characteristics. Hence, an image which has been enhanced from one aspect may end up worst from another aspect. In this study, new image processing techniques have been developed based on findings which have been gathered from characterization of mammogram images. The characterization process covered the analysis of grey level distribution, noise, edge and texture. Detailed understanding of these characteristics, provide a solid basis for the development of new image processing techniques in this study. The new techniques brought forth through this study include contrast enhancement (i.e. Moving Contrast Sweep), noise suppression (i.e. Mean Approximation Adaptive Wiener Filter) and segmentation algorithm (i.e. Mean Median Crossing Segmentation). In addition to that, a new edge detection algorithm (i.e. Delta Variance Edge Detection) has also been developed to assist in microcalcification detection. Furthermore, a new classification system which is based on texture characteristic has also been developed for mass detection. Based on the analysis, it has been found that the Mean Approximation Adaptive Wiener Filter and Delta Variance Edge Detection techniques perform better than their predecessor. The performance of Mean Median Crossing Segmentation and Moving Contrast Sweep techniques is equivalent to existing techniques but they can be implemented through a more practical approach. The mass detection technique through statistical texture analysis demonstrates a lot of potential but still has room for improvement. It is hoped that, the new image processing techniques developed through solid understanding of mammogram image characteristic in this study could provide a strong foundation for the development of medical imaging applications in the future.
- ItemThe Sigficance of spatial factors in influencing the price of heritage properties in George Town, Penang.(2010)The aim of this research is to determine the significance of selected spatial factors and the influence of these spatial factors on heritage property prices in George Town 1. Spatial factors related to location, neighbourhood ·and local amenities such as transportation points, highway, shopping centre and school are tested in this research. Hedonic regression analysis is used to study the relationship between spatial factors and heritage property price in George Town 1. A total of 231 heritage property transaction records from year 1998 to 2004 are used in this analysis. The empirical result shows that spatial factor has significant influence on heritage property prices. 'Ferry route', 'shopping centre' and 'primary and secondary school' are three significant factors influencing heritage property prices in George Town 1. To further verify the significance of the above spatial factors, a spatial autocorrelation analysis is used for the second test. The analysis result indicates that property prices in George Town 1 are positive spatial autocorrelated. The positive spatial autocorrelated transaction prices in George Town reflect that property prices in George Town tend to depend on its neighbour. A geo-statistical method called Kriging is then used to verify the dependency of heritage property prices on its neighbours. A comparison between the predicted prices obtained from the Kriging map with actual transaction prices found that the predicted prices are reasonably close to the actual prices. As the Kriging method uses neighbouring properties prices to predict prices, the findings indicate that spatial factors especially neighbourhood has an influence on heritage property prices in George Town.