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- PublicationThe significance of capillary electrophoresis in the detection of haemoglobin constant spring and its relationship with high-performance liquid chromatography(2021)Introduction: Haemoglobin Constant Spring (Hb CS) is one of the most common non-deletional types of alpha (α) thalassaemia in Southeast Asia region. The nature of this abnormal globin gene is that it is unstable, labile and is present in minute amount in the peripheral blood. Thus, this may lead to underdiagnosis of the disease. This study was conducted to determine the proportion of Hb CS among the Kelantan population and to compare range of peak value in Zone 2 CE findings for 3 groups of Hb CS (heterozygous, homozygous, and compound heterozygous) and their haematological parameters. The study aimed to look at the findings of HPLC in relation to CE results in detecting Hb CS. Study design and methods: This was a cross-sectional study involving secondary data collection from 378 samples which showed peak value on Zone 2 of CE. The samples were taken from the National Thalassemia screening of Form 4 students from all districts in Kelantan. The haematological parameters of red cells were analysed using Sysmex XN 3000 automated blood cell analyser, Hb analysis was performed using automated CE system (CAPILLARYS2 Flex-Piercing System Sebia), HPLC Biorad variant II, DNA analysed using multiplex polymerase chain reaction (PCR) and multiplex Amplification refractory mutation system (ARMS) to detect both deletional and non-deletional α-thalassaemia. Results: 376 samples (99.5%) with presence of peak value on Zone 2 of CE were confirmed to have termination codon CS mutation. Heterozygous Hb CS is the most common type of Hb CS detected in 344 samples (91.5%), followed by compound heterozygous Hb CS which was 31 samples (8.2%) and only 1 sample (0.3%) of homozygous Hb CS. The mean ± SD of peak value in Zone 2 of heterozygous Hb CS and compound heterozygous Hb CS were 0.61 ± 0.13 and 0.77 ± 0.34 respectively. The only sample of homozygous Hb CS showed the value of 4.9% of peak value in Zone 2 of CE. The significant differences of haematological parameters between heterozygous and compound heterozygous Hb CS were observed in haemoglobin level, MCV, MCH and MCHC. This study showed there was a good linear correlation between peak in C-window on HPLC and peak value in Zone 2 of CE in detecting Hb CS, r=0.73. Conclusion: Thus, by combining the haematological parameters and complementary tests of both CE and HPLC, the diagnosis of Hb CS can be detected prior to confirmation by DNA molecular study that is far more expensive.
- PublicationProgression-free Survival And 5-year Clinical Outcomes Post Empirical High Dose Iodine-131 (I131) Therapy In Tenis Syndrome And Mixed Disease Of Differentiated Thyroid Carcinoma(2022-11)Title: Progression-free survival and 5-year clinical outcomes post empirical high dose Iodine-131 (I-131) therapy in TENIS syndrome and mixed disease of differentiated thyroid carcinoma. Background: Patients with radioactive Iodine-131 (I-131) - refractory differentiated thyroid carcinoma have a poor prognosis due to limited treatment options. The limited availability and expensive tyrosine kinase inhibitor and indolent behavior differentiated thyroid cancer are the factors that drive clinicians to treat these patients empirically with high dose I-131 therapy for curative and disease control intent. Method: A retrospective cohort study of progression-free survival in patients who developed TENIS syndrome and mixed disease of differentiated thyroid carcinoma post total thyroidectomy and remnant ablation from 2010-2018. Cohort A included treatment group in which empirical high dose I-131 therapy was administered, and cohort B were those diagnosed with similar conditions but not given therapy. All patients in both cohorts were followed up for five years to look for clinical outcomes in response to treatment. Findings: Sixty-three patients were included, 46 (73%) patients developed TENIS Syndrome and 17 (27%) patients were identified as mixed disease. There were 40 patients (63.5%) who received the empirical high dose I-131 were allocated to cohort A and 23 patients (36.5%) who did not receive empirical high dose I-131 were assigned to the controlled group (cohort B). Twenty-seven patients with TENIS syndrome and 13 patients with the mixed disease were treated with empirical high dose I-131 therapy (cohort A). Empirical high dose I-131 therapy showed prolonged progression-free survival (PFS) compared to the controlled group (hazard ratio, 0.603: 95% CI, 0.308-1.179; p = 0.139) with a 40% reduction in the risk of disease progression at any given time over five years with median PFS in cohort A is at 4.7 years while cohort B is 3.6 years, though it is not statistically significant. At five years, only 20% (n=8/40) of patients in the treatment group had excellent response compared to 26% (n=6/23) in the surveillance group. However, 80% (n= 32/40; cohort A) and 83% (10/12; cohort B) remained structurally and biochemically incomplete response to therapy. Conclusion: Empirical high dose I-131 therapy prolongs progression-free survival in patients with TENIS syndrome and mixed disease. These results suggest that empirical high dose I-131 therapy represents a treatment option for these patients to prevent further disease deterioration despite statistically does not show significant results.
- PublicationRetrospective study on the management of liver trauma: a 7-year experience in a hepatobiliary center(2021)Background: Liver trauma is one of the most common injury in abdominal trauma. For the last three decades, there was a paradigm shift from operative to non-operative management (NOM) in liver trauma, with stable haemodynamic, regardless to the grading of liver injury. There are factors that should be considered for anticipating failure of nonoperative management. Therefore, this study is performed to identify these factors, to ensure that early intervention is done in order to achieve less morbidity and mortality in non-operative management of liver trauma. Methods: This is a retrospective study of case record of patients diagnosed with liver injury in Hospital Sultanah Bahiyah, Alor Setar from 1st January 2012 to 31st December 2018. Subjects who met the inclusion criteria were recruited in this study. The outcome of non-operative management and factors leading to its failure were studied. The data were analyzed using Statistical Package for the Social Sciences (SPSS) version 26. Results: A total of 158 patients were included in this study. They were 12 to 80 years old, with mean age of 25.6 years. The subject pool comprised of 125 males and 33 females. Majority of the liver traumas were due to motor vehicle accidents, 141 (89.2%), followed by fall, 6 (3.8%) and industrial injury 3 (1.9%). Grade III and grade IV liver injuries were the two most common grading with a total of 43 (27.2%) and 42 (26.6%) cases encountered respectively. Fifty-three patients underwent emergency laparotomy and 20 (37.2%) of them developed post-operative complications. Hundred and five patients were treated non-operatively. Majority of the patients in this group were young, mean age of 21.0 years old. Simple logistic regression revealed six predictive factors associated with failure of NOM, including haemoglobin at presentation (p 0.015), blood transfusion status (p 0.008), unit of blood transfused (p 0.014), liver injury grade (p0.001), length of stay (p 0.028) and intensive care unit admission (p 0.041). Multiple logistic regression shown that liver injury grade and length of stay had significant association with failure of NOM, with p value of 0.003 and 0.040 respectively. Conclusion: Non-operative management in liver trauma is a safe approach in haemodinamically stable patients. Factors related to its failure must be considered for better outcome in term of morbidity and mortality.
- PublicationProgression-free Survival And 5-year Clinical Outcomes Post Empirical High Dose Iodine-131 (I131) Therapy In Tenis Syndrome And Mixed Disease Of Differentiated Thyroid Carcinoma(2022-11)Title: Progression-free survival and 5-year clinical outcomes post empirical high dose Iodine-131 (I-131) therapy in TENIS syndrome and mixed disease of differentiated thyroid carcinoma. Background: Patients with radioactive Iodine-131 (I-131) - refractory differentiated thyroid carcinoma have a poor prognosis due to limited treatment options. The limited availability and expensive tyrosine kinase inhibitor and indolent behavior differentiated thyroid cancer are the factors that drive clinicians to treat these patients empirically with high dose I-131 therapy for curative and disease control intent. Method: A retrospective cohort study of progression-free survival in patients who developed TENIS syndrome and mixed disease of differentiated thyroid carcinoma post total thyroidectomy and remnant ablation from 2010-2018. Cohort A included treatment group in which empirical high dose I-131 therapy was administered, and cohort B were those diagnosed with similar conditions but not given therapy. All patients in both cohorts were followed up for five years to look for clinical outcomes in response to treatment. Findings: Sixty-three patients were included, 46 (73%) patients developed TENIS Syndrome and 17 (27%) patients were identified as mixed disease. There were 40 patients (63.5%) who received the empirical high dose I-131 were allocated to cohort A and 23 patients (36.5%) who did not receive empirical high dose I-131 were assigned to the controlled group (cohort B). Twenty-seven patients with TENIS syndrome and 13 patients with the mixed disease were treated with empirical high dose I-131 therapy (cohort A). Empirical high dose I-131 therapy showed prolonged progression-free survival (PFS) compared to the controlled group (hazard ratio, 0.603: 95% CI, 0.308-1.179; p = 0.139) with a 40% reduction in the risk of disease progression at any given time over five years with median PFS in cohort A is at 4.7 years while cohort B is 3.6 years, though it is not statistically significant. At five years, only 20% (n=8/40) of patients in the treatment group had excellent response compared to 26% (n=6/23) in the surveillance group. However, 80% (n= 32/40; cohort A) and 83% (10/12; cohort B) remained structurally and biochemically incomplete response to therapy. Conclusion: Empirical high dose I-131 therapy prolongs progression-free survival in patients with TENIS syndrome and mixed disease. These results suggest that empirical high dose I-131 therapy represents a treatment option for these patients to prevent further disease deterioration despite statistically does not show significant results.
- PublicationRelationship Between Plasma Na Triuretic Peptide Level And Spect-derived Diastolic Parameters(2022)Introduction: Diastolic dysfunction usually precedes systolic dysfunction and heart failure (HF). Patient with elevated natriuretic peptide such as N-Terminal pro Braintype Natriuretic Peptide (NT-proBNP) without failure symptoms and normal left ventricular ejection fraction (LVEF) may suffer from asymptomatic diastolic dysfunction which is categorized under stage B HF (pre-failure stage). Imaging technique for assessment of ventricular dysfunction (diastolic and systolic) usually performed using echocardiography. However, myocardial perfusion imaging using single photon emission computed tomography (SPECT) also can provide pertinent information on ventricular function such as LVEF for systolic function, ventricular peak filling rate (PFR), second PFR (PFR2), first third mean filling rate during diastole (1/3MFR), and time to PFR (TPFR or TTPF) for diastolic performance. Objectives: This study aims to assess the relationship of natriuretic peptide as ventricular biomarker and the diastolic parameters measured by electrocardiogram-gated myocardial perfusion SPECT (Gated MPS) among patient with normal LVEF and no evidence of myocardial ischaemia or infarction, and to analyse the association of SPECT-derived diastolic parameters with clinico-socio-demographic factors as well as to establish the centre-based reference value. Methods: We enrolled 137 patients with normal stress & rest myocardial perfusion and LVEF. The LV volume-filling curve was automatically calculated by Quantitative Gated SPECT (QGS) software using 16-frames list mode method to derive SPECT's diastolic parameters from rest study including PFR normalised to end diastolic volume (EDV), 1/3MFR normalised to EDV, TTPF (or TPFR) and TTPF normalised to R-R interval of cardiac cycle (TTPF/RR). The potential relationship with NT-proBNP, the association with clinico-socio-demographic factors and the reference values were studied. Results: The diastolic parameters by Gated MPS showed no correlation with NTproBNP. PFR and 1/3MFR were consistently reduced as level of NT-proBNP increases but not statistically significant (p=0.231 vs 0.348) and were influenced by age (p = 0.003 vs 0.002), diastolic blood pressure (p < 0.001 respectively) and hypertension (p = 0.031 vs 0.004). PFR had strong association with gender (p < 0.001) and heart rate (p <0.001) but not 1/3MFR. There was a statistically significant difference between diabetic and nondiabetic (p = 0.001); hypertensive and non-hypertensive (p =0.004) for 1/3MFR. Overall, only TTPF and TTPF/RR showed stable measurement with no influence observed with age, gender, blood pressure, heart rate and co-morbidities. The reference value of PFR, PFR2, 1/3MFR, TTPF and TTPF/RR as diastolic parameters were 1.55 ± 0.41, 0.70 ± 0.42, 0.79 ± 0.21, 333 ± 55 and 0.197 ± 0.044 respectively. Conclusion: Diastolic parameters measured by QGS 16-frame Gated MPS showed no relationship with ventricular biomarker; NT-proBNP. PFR, PFR2 and 1/3MFR were influenced by clinico-socio-demographic factors but not TTPF and TTPF/RR.
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- ItemSimulation of preventive and corrective maintenance schedule in reducing machine stoppage and downtime(2017-06)Maintenance approaches or strategies has been studied since many decades ago and nowadays it varies from the complex mathematical approach to improved and simplified yet effective time-based strategies. However, simulation of maintenance strategies is an intermittent field of research thus current maintenance strategies simulation model created a benchmark to imitate the methodology of implement maintenance strategies in real production. Currently, the major drawback of most of the published researchers is in the application of only single machine, single maintenance strategies or multiple machines of the same type working in parallel which does not reflect the real and complex manufacturing system. Thus, this project is conducted to create a model of maintenance strategies integrated with a dynamic manufacturing system. The system consists of five different machines and each cycle time of machines differ considering the shift time of maintenance team and spare part availability. The work has been conducted using WITNESS 14 Manufacturing Performance Edition software. The model was developed to imitate a Surface Mounted Technology (SMT) production system by considering the changeover time, minor and major breakdown, corrective maintenance (CM) as well as preventive maintenance (PM) scheduling. The aim is to study the effect of maintenance strategies towards the machine downtime. The SMT line was simulated and evaluated based on the availability of individual machines via discrete event simulation system. Presuming that each machine has different degradation level, which follows a Weibull distribution, the maintenance scheduling strategies were planned based on First Come First Serve (FCFS) basis if the same type of maintenance strategies is due on different machines but prior to CM. The findings of this project demonstrated that a daily PM schedule can improve the system availability by 30% while increasing the availability of machine up to 90%.
- ItemPhotocatalytic Degradation Of Phenol By Silica Gel-Supported Titania Nanotubes(2012)TiO2 nanotubes and immobilized TiO2 nanotubes were successfully synthesized by a hydrothermal method and binding method. The produced photocatalysts were characterized by the Brunauer-Emmett-Teller (BET) method, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscope (TEM) and X-ray diffraction (XRD). The photocatalytic activities of the photocatalysts were evaluated through the photocatalytic degradation of aqueous phenol solution in a batch reactor. TiO2 nanotubes produced at 130 °C for 3 h showed the highest degradation rate of phenol compared with the other samples prepared at 130 °C for 1 h, 5 h and 7 h, complete degradation being achieved in 130 min. Special focus was given in order to determine the optimum composition of each component (catalyst, support and binder) in the immobilization of TiO2 nanotubes. The highest efficiency of phenol degradation was achieved when the ratios of TiO2 nanotubes: silica gel: colloidal silica was 1:2:20. For the comparison, TiO2 nanotubes and immobilized TiO2 nanotubes showed higher photocatalytic activity as compared with pure TiO2. The photocatalytic performance of TiO2 nanotubes and immobilized TiO2 nanotubes achieved 100 % and 98.0 % respectively, of phenol degradation, whereas pure TiO2 attained only 77.0 % degradation. The photocatalytic activity of the immobilized TiO2 nanotubes was slightly decreased after four cycles for phenol degradation. The loss in percentage of photocatalytic degradation was less than 2 % even after four cycles. The results for the studied operating parameters were: the presence of the anions were found to inhibit the photocatalytic degradation of phenol in the order of SO4 2- > Cl- > HCO3 -; the optimal medium pH was found to be pH 5.5 (natural pH); the air flow rate gave an optimum value of 0.3 L/min; the phenol degradation efficiency decreased as initial phenol concentration increased. Response surface methodology (RSM) based on the central composite design (CCD) was used to optimize and predict the interactions between process variables by reducing the numbers and the times for the experimental runs. Finally, the reaction kinetics of phenol degradation by the immobilized TiO2 nanotubes obeyed well with the Langmuir-Hinshelwood model. The values of the reaction rate constant, k and the adsorption constant, K obtained were found to be 0.9324 mg/L.min and 0.0121 L/mg, respectively.
- ItemEvaluation Of Salmonella Typhi Antigens Hlye And Ynce For The Detection Of Typhoid Fever And Its Carriers(Universiti Sains Malaysia, 2019-06)Salmonella Typhi (S. Typhi) is the causative agent of typhoid fever (TF) that causes millions of infections and 1% of mortality worldwide. TF is highly endemic in Southeast Asia and sub-Saharan Africa. Certain individuals with TF may not recover fully and can become carriers that do not show any symptoms of the disease. The carriers can then spread the disease when they come into contact with food and water. Antibodies against S. Typhi HlyE are elevated among patients with TF compared to healthy individuals, while antibodies against YncE were reported to be elevated among carriers of S. Typhi. Rapid and accurate methods to diagnose individuals with TF or who are carriers are crucial to manage the disease. In this study, recombinant HlyE and YncE antigens were found to be useful for the identification of individuals with TF and those who are possible carriers. Firstly, recombinant HlyE and YncE were expressed and purified. Next, rHlyE and rYncE ELISAs were developed to enable quantitative screening of many samples simultaneously to identify those with elevated IgM, IgG and IgA antibodies against the antigen. A total of 425 serum samples (acute typhoid patients, carriers, food handlers, other febrile, and healthy individuals) were screened with the ELISAs.The rHlyE-IgG, -IgA and -IgM ELISAs demonstrated a sensitivity of 70%, 80% and 11% respectively to detect acute typhoid patients, and with a combined sensitivity of 83%.The rYncE ELISA identified 16 possible carriers based on their antibody profiles. Taken together, this study showed that HlyE antigen could be used to identify individuals with TF while the YncE antigen may be used to identify possible carriers, but further validation is required.
- PublicationFactors Affecting The Use Of Gamification In Online Learning Environment Among School Teachers In The Kingdom Of Saudi Arabia(2023-05)The use of technology and e-learning systems in classrooms can have a significant impact on students’ learning. Not to be left behind, the Saudi government launched the ‘Future Gate’ project to implement technology in secondary schools in which gamification is applied in this e-learning platform. However, what are the factors that might influence its acceptance and utilization among the school teachers? Specifically, this study examined the effects of performance expectancy, effort expectancy, social influence, hedonic motivation, facilitating conditions, and habit on teachers’ behavioural intention to use gamification in teaching and learning activities in the Future Gate platform. It also investigated the impact of age, gender, and experience on these variables. In addition, the study evaluated the effects of task and technology characteristics and how they influence teachers’ perception of Task-Technology Fit (TTF) and the teachers’ behavioural intention to use gamification. This study utilised SEM-Partial Least Square (PLS-SEM) to analyse the relationships between the constructs identified from the literature review. A total of 328 secondary school teachers participated in this study from seven districts in Saudi Arabia.
- ItemNurses' knowledge and practice regarding prevention of surgical site infection (SSI) in Hospital Universiti Sains Malaysia (USM)(Pusat Pengajian Sains Perubatan, Universiti Sains Malaysia, 2021-06)Surgical site infection is an infection that occur 30 days after surgery and cause many effects such as increasing risk of death, increasing hospital stay and financial constraints for patient and health care system. A cross sectional study has been conducted to determine nurses’ knowledge and practice regarding prevention of SSI in Hospital USM. This study also examined the difference of knowledge and practice between general surgery and orthopaedic nurses. Pearson Chi-square was used to determine the association between clinical working experience with knowledge and practice towards prevention of SSI. A total of 66 nurses, 34 nurses were from surgical and 32 nurses from orthopaedic wards were recruited through proportional sampling. Data were collected September 2019 until June 2020 using self-administered questionnaires and analysed using SPSS version 26.0 for Window. Ethical approval was obtained from Human Research Ethics Committee (HREC), Universiti Sains Malaysia. The mean age of the participants was 31 years old. The results revealed staff nurses were having poor knowledge level (M=16.18, SD= 2.745) regarding prevention of SSI. Meanwhile for level of practice, nurses were found to be having good practice towards prevention of SSI (M=67.82, SD=6.44). There was no significant difference in knowledge between general surgery and orthopaedic nurses (p=0.467). While, there was significant difference in practice between general surgery and orthopaedic nurses (p=0.013). There was no association to be found between clinical working experience with knowledge (p=0.834) and practice (p=0.197) regarding prevention of SSI. It showed that nurses need more exposure towards SSI and its prevention for them to identify, assess and implementing the correct practice. As a conclusion, it is shown that knowledge and practice towards SSI is important as the results shows that nurses in Hospital USM had insufficient knowledge. A workshop or course training should be implemented to enhance their knowledge.