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- PublicationGlobal Differential Gene Expression In Hypoxic Hepg2 Upon Sirtuin-1 Upregulation And Downregulation(2025-04)Hepatocellular carcinoma (hcc) is one of the leading causes of cancer death worldwide, largely due to its poor prognosis and the emergence of chemoresistance, particularly exacerbated by the hypoxic tumor microenvironment (tme). Sorafenib, one of the targeted cancer drugs, is commonly used to treat advanced hcc. However, this treatment frequently induces drug resistance. Sirtuin-1 (sirt1) is found to be associated with chemoresistance and linked to tumor angiogenesis under hypoxia, which may serve as a potential molecular target for hcc treatment. Sirt1 is significantly dysregulated in various cancers, including hcc. Therefore, this study aims to elucidate sirt1 as a potential molecular target for hcc progression in hypoxic conditions. To achieve this objective, crispr/dcas9 was utilized to modulate sirt1 gene expression in hepg2 cells. 20 bp grnas targeting sirt1 were cloned into the plasmid vector pspgrna and verified by sequencing. Sirt1 upregulation and downregulation were accomplished by transducing hepg2 cells with vp64-activator and krab-repressor plasmids, followed by antibiotic selection to establish hepg2_crispra_vp64 and hepg2_crispri_krab stable cells. The transfection with grna was done in normoxic condition followed by incubation in hypoxia. Result on optimization shows upregulation and downregulation to 1.7- and 0.4-fold change in transfected hepg2_crispra_vp64 and hepg2_crispri_krab stable cells, respectively.
- PublicationOptimization Seaweed Drying Efficiency Using Hybrid Solar Dryers And Sparse Robust Regression Models(2025-04)Data analytics in statistics is vital for extracting insights, identifying patterns, and guiding decisions. In precision farming, particularly post-harvest management, challenges arise from iot sensor dependency, system complexity, and variable interactions, leading to issues like variability, multicollinearity, and sensitivity to outliers. Addressing these challenges requires improved data inclusivity, robust data management, and cross-sector collaboration to unlock the full potential of analytics. Variability in agricultural systems impacts crop yield and post-harvest processes. Heterogeneity in sensors, data collection methods, and transmission protocols complicates agricultural drying. Multicollinearity, where independent variables are highly correlated, creates difficulties in post-harvest monitoring as overlapping environmental data from multiple sensors obscures the impact of individual variables. Fluctuations due to environmental changes, sensor errors, and human interventions further complicate modeling, requiring robust statistical methods capable of handling noise and outliers.
- PublicationHigh-Speed Octree Data Structure For Three-Dimensional (3d) Geographical Information System (Gis) Spatial Analysis In Slope Stability Application(2025-05)Geographic information systems (gis) can more realistically model real-world complexity through three-dimensional (3d) spatial analysis than traditional two-dimensional (2d) approaches, but this approach requires significant algorithmic and computational resources, particularly for critical tasks such as slope stability assessment. Most current gis platforms effectively manage 2d/2.5d data but they experience difficulties when dealing with true 3d data structures and often need data conversion processes to the raster. The octree stands as a basic structure for three-dimensional representation, but standard octree implementations demonstrate poor performance in neighbour searches through their slow tree traversal method. This research introduces the high-speed octree (hso) data structure, designed to overcome these limitations by integrating octree principles with modern computational techniques. The fundamental approach of hso stores three-dimensional spatial information directly within the data structure. The system uses an efficient 3-bit binary encoding system at every hierarchical level to determine node paths.
- PublicationRepresentations Of Individuals With Mental Illness In Selected News Reports Of The Star Online And Malaysiakini: A Critical Discourse Analysis(2025-05)Despite the crucial role of news media in shaping dominant narratives about mental health, existing literature shows that news representations of individuals with mental illness have generally been stigmatising. Notably, research on media portrayals of this group has mainly focused on mainstream newspapers, with little attention given to independent newspapers. Therefore, this study aims to compare how individuals with mental illness are represented in two widely read online newspapers in malaysia: the mainstream newspaper the star online and the independent newspaper malaysiakini. Using critical discourse analysis (cda), the study examines 12 selected news reports from each newspaper at both textual and ideological levels. The analysis is informed by van dijk's (1980) theory of semantic macrostructures, halliday and matthiessen’s (2014) systemic functional linguistics, and van dijk’s (1998) theory of ideology. The study’s findings reveal that representations of individuals with mental illness in both newspapers were broadly comparable across all three aspects of textual analysis, highlighting their perceived dangerousness and vulnerability. Furthermore, they were typically positioned as a ‘voiceless’ group in both newspapers. In contrast, individuals without mental illness, notably those in positions of power, were accorded the space to ‘give’ voices on behalf of those with mental illness.
- PublicationApplication Of In Silico And In Vitro Approaches On Repurposed Drugs Targeting Putative Rho Gtpase And Rhogap Of Giardia Lamblia.(2025-05)Giardia lamblia is a globally distributed protozoan parasite that causes an intestinal disease named giardiasis. The primary treatment relies on nitroimidazole drugs such as metronidazole, tinidazole, and albendazole. However, the incidence of refractory cases had increased, leading to therapeutic non-compliance. Although numerous research studies have been conducted to address these concerns, they remain unresolved. The small gtpase, rho subfamily protein, and its positive regulator, putative rho gtpase activating protein (rhogap), were found to be involved in various biological and cellular processes. They were found to work in tandem in regulating encystation and membrane trafficking and were involved in the metabolic processes of this protozoan parasite. Thus, it was hypothesized that inhibiting these proteins would lead to the killing of the parasite. The target sequence analysis showed that two repurposed drugs, dextromethorphan and azathioprine, were matched to the small gtpase, rho subfamily proteins. On the other hand, three re-purposed drugs were matched to the putative rhogap, which were imatinib, dasatinib, and ponatinib. Molecular docking analysis showed the binding energies of the five drugs to their respective proteins were -8.5 kcal/mol, -8.0 kcal/mol, -7.0 kcal/mol, -5.3 kcal/mol, and -6.8 kcal/mol, represented by imatinib, ponatinib, dasatinib, azathioprine, and dextromethorphan, respectively. Molecular
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- ItemApplication of control mechanisms on marketing decisions in multinational company marketing units in Malaysia(2006)Research in international subsidiary management has made significant advances in understanding the cross-border control mechanisms. However there is very limited research done on issues related to marketing related control mechanisms. Using a questionnaire survey, this study investigates the types and level of control mechanisms used specifically on marketing-related decisions, and examines the determinants and moderating factors of the mechanisms. From the responses of 96 local marketing units of multinational companies operating in Malaysia, four types of control mechanisms on marketing decisions are identified, namely direct value control, direct support control, control by socialization and networks and output control. Control by socialization and network is found to be used most extensively in marketing decisions. Among marketing mix elements, product decisions received the highest level of control. Factors influencing the choice and the level of control mechanisms include organization model, the size of local marketing unit, and interdependence between local unit and headquarters. The relationship between the determinants and control mechanisms are found to be moderated by environmental complexity and target market.
- PublicationKnowledge and attitude towards Vaginal delivery and cesarean section Among primigravida in hospital Universiti Sains Malaysia.(2016)As first time mother, primigravida might have different knowledge and attitude towards vaginal delivery (VD) and cesarean section (CS). A cross sectional study was carried out to assess knowledge and attitude towards VD and CS among primigravida in Hospital USM. A total of 105 primigravida attending antenatal visit in teaching hospital completed selfadministered questionnaires. Sampling was done using non-probability purposive sampling technique. Data was analyzed using the software package SSPS version 22. Statistical significance was considered at p value <0.005. This study found that majority of the participants have good knowledge towards VD and CS (51.4%, n=54). Chi Square test showed a significant association between monthly household income with level of knowledge towards VD and CS among primigravida (p=0.022). This study found no association between other socio-demographic characteristics (age, highest education level and occupational status) with knowledge on VD and CS. For attitude towards VD and CS, the current study found no association with socio-demographic characteristics (age, monthly household income, highest education level and occupational status). Chi Square test showed a significant association between the level of knowledge and attitude towards VD (p=0.025). In conclusion, the study findings show a need for educating pregnant women, especially among primigravida about the pros and cons of different modes of delivery to maternal and perinatal health.
- ItemPerak Shimbun August 07 2605 (07 August 1945).(1945-08-07)
- PublicationIntracranial volume post cranial expansion surgery using 3D CT scan imaging in children with craniosynostosis(2018)Background: Craniosynostosis is a congenital defect that cause one or more suture to fuse prematurely. Cranial expansion surgery which consist of cranial vault reshaping with or without fronto-orbital advancement (FOA) is done to correct the skull to a more normal shape of the head as well as to increase the intracranial volume. Therefore, it is important to evaluate the changes of intracranial volume (ICV) after the surgery and the effect of surgery both clinically and radiologically. Objective: This study is to (1) evaluate the ICV in primary craniosynostosis patients after the cranial vault reshaping with or without fronto-orbital advancement and to compare between syndromic and non-syndromic synostosis group, (2) to determine factors that associated with significant changes in the ICV postoperative, and (3) to evaluate the resolution of copper beaten sign and improvement in neurodevelopment after the surgery. Method: A prospective observational study of all primary craniosynostosis patients who underwent operation cranial vault reshaping with or without FOA in Hospital Kuala Lumpur from January 2017 until Jun 2018. The ICV preoperative and postoperative was measured using the 3D CT imaging and analysed. The demographic data, clinical and radiological findings was identified and analysed. Result: 14 cases (6 males and 8 females) with 28 3D CT scan were identified. The mean age of patients was 23 months. The patients were 7 syndromic synostosis (4 Crouzon syndrome and 3 Apert syndrome) and 7 were non-syndromic synostosis. The mean preoperative ICV was 880 mL (range, 641-1234 mL) while the mean postoperative ICV was 1081 mL (range,811-1385 mL) The difference was 201 mL which was statistically significant (P<0.001). In comparison, the mean volume increment for syndromic synostosis and non-syndromic synostosis were 282 mL and 120 mL respectively. The difference was statistically significant (P<0.004). Me Nemar’s test was used to analyse pre and post-operative changes within the same patients. At 3 months post-surgery, all 13 patients with copper beaten sign pre-operatively did not show complete resolution on 3D CT imaging. Therefore the p-value was insignificant (P>1.0). While 2 patients with neurodevelopmental delay pre-operatively showed no improvement during assessment at 3 months post-surgery. Again the p-value was insignificant (P>1.0). Hence, there were no significant resolution in copper beaten sign and improvement in neurodevelopmental delay in this study. Conclusion: Surgery in craniosynostosis patients increases the intracranial volume besides it improves the shape of the head. From this study, the syndromic synostosis had better increment of intracranial volume compared to non-syndromic synostosis.
- ItemDifferences in the chromatic visual event related potentials in number and non-number plates of the ishihara colour vision test(Kampus Kesihatan, Universiti Sains Malaysia, 2017-04)Event-related potentials (ERPs) are very small voltages existed within the brain structures in response to particular events or stimuli. Ishihara colour vision test is a test that made of a number of coloured plates that might be either number plates or non- number plates. In a recent study, we looked for the differences of chromatic visual ERPs in number and non-number plates during visual presentation session in trichromatic participants to discover furthermore about which plate design can elicit more cognitive processes like attention and memory wherein these differences might be used as a new clinical knowledge, which might be applicable clinically in the future. A total of 25 participants both males and females were used for our study. All of them were apparently healthy with normal colour vision. Firstly, we recorded the electroencephalography (EEG) when participants attended to the lab in the Hospital of Universiti Sains Malaysia (HUSM) from 19 electrode sites using 128 electrode sensors net which were applied on the participant’s scalp according to 10-20 international electrode placement system. Then, we recorded ERPs through presenting a visual oddball task of number and non-number plates in a random order at inter-stimulus intervals (ISI) of 2 seconds.The latency and amplitude of the evoked N100, N200, P200 and P300 components were identified. To determine the statistical significance, the amplitude and latency of all components and the reaction time (RT) was analysed by using paired-t test. The results showed higher amplitudes of N100, P200 and N200 ERP components for number plates indicating that the participants had greater visual selective attention, visual searching perception and visual identification for number plates as compared to non- number. The results of longer latencies of N200 and P300 ERP components and the higher amplitude of P300 for non-number plates signifying that the participants were taking more time to identify and distinct visually the non- number plates and delaying in cognitive processing and attention for non- number plates as compared to number plates. About RT, the results showed significant increasing in mean of the non- number plates as compared with number plates indicating that the participants responded to number plates faster than non- number plates.Therefore, we concluded that besides colour vision tests, in research fields, the plates of Ishihara colour vision test could be potentially used in studies that deal with cognition, attention and memory which has been evidenced through the differences of the latencies and amplitudes of N100, P200, N200 and P300 ERP components in number and non-number plates viewing in our study. The findings of this study might be translatable clinically in patients with neuropsychological and attention disorders to discover new findings that might give benefits to the patients, medical researchers and clinicians in the future.