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- PublicationThe synthesis and characterization of hydroxylapatite microtubules/polylactic acid GTR membranes and its effect on periodontal bone regeneration(2024-11)The general objective of the study is to develop novel hydroxylapatite microtubules/PLA GTR membranes and evaluate them for mechanical and biological properties. HAp microtubules were prepared through hydrothermal synthesis. The composition and morphology of the synthesized materials were examined by a scanning electron microscope (SEM), transmission electron microscopy (TEM), Xray powder diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Then the novel hydroxylapatite microtubules/PLA GTR membranes were fabricated. The membranes were verified whether they met the clinical mechanical requirements in degradation and stretching properties. In addition, we examined its interaction with human periodontal ligament stem cells (hPDLSCs), harvested from healthy teeth. The osteogenic effect of the membrane on hPDLSCs was examined by evaluating the gene and protein expressions of the RUNX2, OPN, and OCN using Quantitative PCR (qPCR) and Western blotting analysis, respectively. In this study, all data for the mechanical property tests, which include water contact angle tests, tensile tests, swelling analysis and biodegradation analysis were expressed as mean and standard deviation. For cell proliferation and osteogenic differentiation experiments, the data were numerical. The normality of distribution was assessed using Q-Q plot analysis. In some cases, natural log transformation was employed to aid in representing data that exhibited normal distribution. The significance level was set at p = 0.05. The HAp microtubules/PLA membrane had better tensile and breaking strengths and lower fracture productivity than the PLA membrane. The expansion rate reached 34% after 2 h, and the degradation rate exceeded 25% after 40 days. Water contact angle measurement results showed that the bilayer membrane was hydrophilic on one side and hydrophobic on the other side. The results of the cell experiments also showed that the membrane had no cytotoxicity. The number of cells in the HAp microtubule/PLA membrane group was found to be significantly higher than that observed in the group with a PLA membrane (p<0.05). Furthermore, the expression of genes and proteins associated with bone composition was significantly elevated in the HAp microtubule/PLA membrane group compared to the HAp powder/PLA membrane and hPDLSCs group (p<0.05). The HAp microtubule side can promote the expression of genes and proteins related to osteogenesis, while the PLA side can inhibit cell adhesion. The HAp microtubules/PLA membrane has stability and good mechanical properties. The double-layer structure has the function of a biological barrier and promotes bone formation.
- PublicationPremature mortality from cardiovascular disease: global burden and country-specific estimate through review study, trend analysis, prediction modelling, and causal inference study(2024-12)Cardiovascular disease (CVD) is a leading cause of premature mortality worldwide, with its burden growing in recent years. Despite considerable research into CVD, there are noticeable gaps in addressing premature mortality associated with it. For example, there is insufficient information on global research activity and pool estimation of the global burden of premature CVD mortality from existing literature. Additionally, within-country estimates of this burden and country-specific CVD risk profiles are lacking. Therefore, this thesis aims to comprehensively analyze and understand various aspects of premature CVD mortality, including global research activities, estimating the global burden of CVD related to premature mortality, examining country-specific trends and risk profiles for premature CVD mortality, and constructing causal pathways for premature CVD mortality. This thesis consists of five interrelated studies aimed at addressing all research objectives. The first study summarizes the global publication information related to premature mortality through bibliometric analysis. The bibliometric analysis shows that premature mortality research has increased substantially in the past decade; however, there have been disparities in research output between high-income countries (HICs) and low-middle-income countries (LMICs), emphasizing the need for collaborative efforts in LMICs. In the second study, consisting of two parts: Study 2a, a systematic review concentrating on premature CVD mortality using the Years of Life Lost (YLL) indicator, followed by study 2b, a subsequent meta-analysis based on the age-standardized mortality rate (ASMR) indicator. Studies 2a and 2b underscore the persistent burden of premature CVD mortality, particularly in LMICs and among men, emphasizing the importance of targeted interventions and public health strategies. The third study involves trend analysis utilizing Malaysia country-specific mortality data from Dapartment of Statistics Malaysia employing a joinpoint regression model. This study reveals a persistent increasing trend of premature CVD mortality rates in Malaysia over the past decades, underscoring the ongoing burden in the country. In study four, a modeling study is conducted to assess the premature CVD risk profile by applying various survival models. This study utilizes data from Malaysia's National Health and Morbidity Survey (NHMS) conducted in 2006, 2011, and 2015, linked with mortality records through 2021. The semi-parametric and parametric survival models both highlight the considerable impact of socioeconomic status and modifiable risk factors on premature CVD mortality in Malaysia. Finally, the fifth study entails a causal inference study systematically demonstrating the construction of a Directed Acyclic Graph (DAG) model for premature CVD mortality. This study introduces a new approach integrating evidence synthesis and expert opinion using the Fuzzy Delphi method to construct the DAG model, followed by testing the model with available data. This step demonstrates a step-by-step process for constructing a causal model, offering a systematic, practical, and transparent approach, contributing to DAG methodology. In summary, through meticulous methodologies, the findings of this thesis contribute to the growing body of literature on premature mortality from CVD and provide valuable insights and frameworks for informing public health strategies and guiding future research endeavours in tackling premature CVD mortality.
- PublicationStigma, anxiety, depression, social support and quality of life in young women with breast cancer undergoing chemotherapy: a predictive model(2024-12)Young women diagnosed with breast cancer (BC) are increasing annually, and they are prone to mental health problems, which significantly reduce their quality of life (QoL). Social support is crucial for enhancing the QoL in patients with BC. However, the relationship between stigma, anxiety, depression, social support, and QoL in young women with BC undergoing chemotherapy remains unclear. This study aims to examine the relationship between stigma, anxiety, depression, social support, and QoL among young women with BC undergoing chemotherapy. This cross-sectional study was done in the First Affiliated Hospital of Guangxi Medical University, China, from December 2022 to October 2023. The research instruments were the Functional Assessment of Cancer Therapy-Breast (FACT-B), the Social Support Rating Scale (SSRS), the Social Impact Scale (SIS), and the Hospital Anxiety Depression Scale (HADS). SPSS 26.0 and AMOS28.0 software were used for statistical analyses. Data were analysed using descriptive, univariate, correlation analysis, structural equation model (SEM) and multiple linear regression (MLR). 196 women with BC aged ≤ 40 were included in the study. The mean QoL score of participants was at a moderate level, 98.01 (SD = 16.97). The findings indicated participants' QoL was associated with education level (p = 0.010), residence (p = 0.004), surgery type (p = 0.021), current chemotherapy cycle (p = 0.002) and postoperative time (p = 0.020). Stigma (r = −0.590), anxiety (r = −0.344), and depression (r = −0.236) were negatively correlated with the QoL among young women with BC. However, there was a positive correlation between social support and QoL (r = 0.416). In addition, social support significantly mediated the impact of stigma (β = −0.214, p = 0.016) and depression (β = −0.084, p = 0.030) on the QoL. However, social support did not significantly mediate the relationship between anxiety and QoL (β = 0.054, p = 0.105). 41.3% of the variance in QoL among young women with BC was explained by stigma, anxiety, and social support. In conclusion, a significant interaction exists among stigma, social support, anxiety, depression, and QoL in young women with BC undergoing chemotherapy. This finding highlights the importance of assessing the psychological challenges faced by young women with BC as part of routine care. Furthermore, it underscores the need for the future development and implementation of mental health support programs tailored to young women with BC undergoing chemotherapy.
- PublicationDari Daerah Ke Kerajaan : Sejarah Politik Perlis, 1841-1957(2000)Dua objektif tesis ini ialah untuk membina sejarah penubuhan sebuah kerajaan Melayu bernama Perlis dan untuk menggalurkan pertumbuhannya dari sebuah unit politik yang baru di alam politik Melayu yang berjuang bagi hak mengekalkan kewujudannya sehingga sebuah entiti berautonomi di dalam Persekutuan Tanah Melayu. Penemuan-penemuannya menawarkan empat sumbangan utama. Paling penting ia telah mendedahkan satu bahagian di dalam sejarah Malaysia yang paling sedikit dikenali, iaitu sejarah negeri Perlis. Kedua, dalam menggalurkan sejarah Perlis dari permulaannya sebagai sebuah daerah Kedah sehingga menjadi sebuah kerajaan baru pada 1841, tesis ini telah cuba mendedahkan pelbagai ketidaktepatan berkenaan kelahirannya yang wujud dalam pensejarahan setakat ini lalu menetapkan tarikh penubuhannya yang didapati lebih betul dan tepat. Ketiga, dan sehubungan dengan itu, kajian ini telah memperbetulkan beberapa tanggapan umum yang utama berkenaan sejarah Malaysia dan sejarah Kedah. Sedangkan kebanyakan pemberontak berjuang demi menaiki takhta yang ada atau demi melawan British dan Siam dan apabila gagal terpaksa meninggalkan kampung halaman, pemberontak dalam kajian ini, yakni Syed Hussein bin Syed Harun Jamalullail, telah berjuang demi membina sebuah takhta dan wangsa pemerintah yang baru bagi dirinya. Sememangnya ia bukan berjuang semata-mata untuk berdiri di belakang Sultan tetapi untuk mendapatkan kemerdekaan daripadanya.
- PublicationIn vitro antioxidative evaluation of plukenetia volubilis aqueous extract in ovarian aging process(2025-01)Ovarian aging is the aging process related to the decline in ovarian cellular function primarily driven by oxidative stress which affects hormonal production, resulting in reduced fertility and hormonal dysfunction in women. Although there are many medications have been developed to increase fertility and reproductive hormones such as clomiphene citrate and gonadotropins, they can cause short- and long-term effects on women. Plukenetia volubilis (Sacha Inchi) is a plant that originated from Northwestern Brazil and Peru and has proven to contain high antioxidant contents such as tocopherols and phenolic compounds. Therefore, our study aims to evaluate the antioxidative potential of P. volubilis aqueous extract in combating oxidative stress during the ovarian aging process using in vitro models. This study assesses the total phenolic content of P. volubilis aqueous extract via total phenolic content (TPC) assay, its radical scavenging ability via DPPH assay, and its protective effects on granulosa cells (COV434) subjected to oxidative stress via MTT assay. Ascorbic acid is used as a standard antioxidant to compare the results. As a result, the TPC assay confirms the presence of significant phenolic content in the extract where the phenolic contents increase as the concentration increases from 0.2 mg/ml to 15 mg/ml. Next, The DPPH assay shows the increase of DPPH radical scavenging with the IC50 value of 2.27 mg/ml. P. volubilis aqueous extract also shows a significant radical scavenging activity when compared to ascorbic acid (p = 0.009). Additionally, the MTT assay reveals the significant protective effects of the extract against hydrogen peroxide-induced oxidative stress in COV434 cells when compared to ascorbic acid (p = 0.089) with the EC50 value of 23.82 mg/ml. This is proven by increasing cell viability when treated with P. volubilis aqueous extract. Overall, the findings successfully underscore the promise of P. volubilis as a natural antioxidant to mitigate oxidative stress-related ovarian aging
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- PublicationDesign of a retrofit inferarm cruthes(2008-04-01)The walking stick is a great aid when the person had an accident and his walking is impaired. It provides steadiness and stability, allowing the user to get around pretty well. By the way, for a person that unable to walk, the easiest way to help them to get around is using a wheelchair. It would help them hanging around easily with no burden to walk. But, wheelchair is not able to use in all aspect. For example, the user can't use the wheelchair to go up the staircase. Furthermore, if a person always sits on the wheelchair s without exercise, the bones of legs will get weaker. The main objective of this project is to design a crutch that can assist the disable or leg's injury person to climb up the staircase. It would help to prevent further damage or accidents when the user climbs up the staircase. Besides, the user is able to maintain proper posture, relieves damaging. stress, and reduces the overall chance of injury when climbing staircase. The project has completed with 3D solid modeling of the designed crutches with SolidWork 2007. Furthermore. COSMOS analysis was done on the critical parts of the designed crutches to make sure the factor of safety required was achieved.
- PublicationEvaluation of captopril and nefediplne in Treatment of hypertension secondary to Post streptococcal acute Glomerulonephritis - A randomized control trial.(2012)Post-streptococcal Acute Glomerulonephritis (PSAGN) is still common in Malaysia. Hypertension is one of its main complications which can lead to severe morbidity in children. Conventional method in treating hypertension in these patients was to use nifedipine to reduce the blood pressure. Recent study in the pathophysiology of the disease had shown apart from water and sodium retention, inappropriate production of angiotensin II could also contributes to the development of hypertension. Captopril, an angiotensin converting enzyme inhibitor can help to reduce the production of angiotensin II which can cause blood pressure reduction. To compare the effectiveness of captopril versus nifedipine in controlling blood pressure in children with PSAGN with hypertension. This was a double blinded randomized controlled trial, registered with ANZCTR (Trial No: ACTRN12611000778987) All children admitted to Wad 6 Selatan HUSM diagnosed clinically with PSAGN with hypertension during a one year study period are eligible for the study. Subjects were randomized either to receive nifedipine (control) or captopril (intervention). Outcomes measured are blood pressure changed in the first 4 hours and blood pressure changes until Day 3 of starting the medication, duration of days to achieve blood pressure control, total duration of admission and the need to use additional medication. Blood urea and serum creatinine levels are compared from before starting treatment and at Day 3 after starting treatment. Out of 40 patients who were recruited and randomized, only 19 from the nifedipine treatment group and 13 from the captopril treatment group completed the study. Both treatment groups had no difference in their baseline data. Nifedipine produces a more significant reduction in SBP and DBP compared to captopril in the first 4 hours of starting treatment (SBP p= 0.001, DBP — 0.016). There was no difference in reduction of SBP and DBP after 8 hours of treatment between the groups (SBP p=0.630, DBP p=0.497). There were no significant differences in the duration of blood pressure normalization (nifedipine: 2.7 days, captopril 2.9 days, p= 0.803) and duration of admission (nifedipine: 6.9 days, captopril: 5.4 days; p=0.183) and the need for additional medication to control the blood pressure (p=0.32) between the groups. Changes of blood urea and serum creatinine levels were not significant before and after treatment (Blood urea changes, /?= 0.564; serum creatinine changes, p- 0.236). Nifedipine produces more significant blood pressure reduction in SBP and DBP in the first 4 hours of starting treatment.
- PublicationDiet quality and predictor factors of body weight status among children with learning disabilities in Kelantan(2022-08)Evidence suggests that children with Learning Disabilities (LD) have unhealthy Body Weight Status (BWS) and poor dietary patterns. A cross-sectional study was conducted to determine the diet quality and the predictors of Body Mass Index (BMI) of LD children. This study recruited LD children who attended the Special Education Integration Program from nine schools located in districts with high, moderate and low socio-economic status in Kelantan. Parents completed a Malay language self-administered questionnaire on demographic and socio-economic background, child’s feeding problems, food frequency questionnaire and comprehensive parental feeding practices. Height and weight of children were measured by researcher to determine BWS. Diet quality was assessed using The Malaysian Healthy Eating Index. Multiple linear regression analysis was applied to test the research hypothesis. A total of 259 children with LD aged 10.54±1.69 years (68.0% males, 32.0% females) participated in this study. Their average BMI was 18.38±4.79 kg/m2; males (18.79±4.76 kg/m2) had significantly higher BMI than females (17.52±4.77 kg/m2), p= 0.046. The prevalence of underweight, thin and severely thin were 11.9%, while 28.1% were overweight and obese. The diet quality average score was 48.15±9.23%, where 40.5% of the children were at risk of poor diet quality. The total daily energy intake was 1831.96±542.15 kcal with a mean carbohydrate intake (241.80±74.75g), protein intake (76.10±25.54g) and fat intake (63.42±21.33g), respectively. Majority of children had a higher score for the occurrence of rapid eating (2.00±1.32), food refusal (1.47±1.35), and food selectivity (1.26±1.13) during mealtimes in the past six months. Parental feeding practice including pressure to eat (Beta =-0.282), restriction of weight control (Beta =0.351) and modelling (Beta =-0.162), child age (Beta =0.222), and childbirth weight (Beta =0.137) were significantly related to BMI (R=0.561, R2=0.315; F(5,217) =19.972, p<0.001). The current findings suggested that early detection of nutrition issues in children with LD and regular positive feeding practice by parents during mealtime is essential to address the poor nutritional status of LD children.
- PublicationAir flow in an air conditioning car(2002-03-01)It is necessary for cars in Malaysia to have air-conditioning due to its environment and weather. Basically, this final year project covers the analysis of airconditioning in a model of general shape cabin of a car. For this computer assisted analysis, it involves computation of airflow in the cabin from different sources of airflow positions. The title of my project is “ Airflow In An Air-Conditioning Car”. The analysis was carried out in a standard basic shape of car cabin design which is available in Malaysia. Analysis was in three dimensional (3D) case.
- PublicationModelling and simulation of bio-oil production from palm oil biomass via fast pyrolysis using aspen plus(2021-07-01)The increase in energy consumption, limited fuel resources, massive dependency on fossil fuels, and greenhouse gas emission has resulted in increased research development on renewable energy sources. Renewable energy is the best option for meeting the current energy demands and reduce the dependence on fossil fuels. In this final year project, three palm oil biomass, namely empty fruit bunches (EFB), mesocarp fibre (MF), and palm kernel shell (PKS) were optimized to produce bio-oil via fast pyrolysis. Process modelling and simulation were carried out using ASPEN PLUS V10.0. The simulation includes pre-treatment, fast pyrolysis section, gas-solid separation, and bio-oil refining section. The model developed was successfully validated with the experimental data obtained from literature. Then, the effect of pyrolysis temperature and residence time during the fast pyrolysis of oil palm biomass were studied to maximize the yield of bio-oil product. Based on the results, the maximum bio-oil yields for EFB, MF, and PKS were 56.46 wt.%, 47.39 wt.%, and 44.03 wt.%, respectively, obtained at a temperature of 550 °C and residence time of 2 s. PKS achieved the highest biochar and gas yield of 49.77 wt.% and 37.21 wt.% at 450 °C and 600 °C, respectively due to its highlignin content. The obtained yields in this study are consistent with experimental results found in the literatures. Therefore, the model developed can be used to optimize fast pyrolysis process for different biomass sources without the need to perform complex experimental investigations. Such model will make an important contribution on the improvement and intensification of fast pyrolysis of biomass.