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- 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
- PublicationEvaluation of the hemavision-28q fusion transcript for acute leukemia screening panel(2025-01)Acute leukemia is a hematopoietic cell malignancy characterized by excessive proliferation of immature blood cells, resulting in severe disruption of normal hematopoiesis. The accurate and timely discovery of genetic abnormalities, particularly chromosomal translocations, is crucial for effective acute leukemia diagnosis, prognosis, and therapy planning. This study compares the performance of the HemaVision-28Q kit, a real-time quantitative PCR (RT-qPCR)-based assay, to the HemaVision-28N assay, which uses nested PCR to detect fusion gene transcripts associated with acute leukemia. The goal was to evaluate HemaVision-28Q's sensitivity, specificity, and clinical value as a diagnostic tool, as well as its capacity to detect both positive and negative fusion transcript cases. Archived RNA samples from the peripheral blood and bone marrow of acute leukemia patients were examined using the HemaVision-28Q and HemaVision-28N assays. The HemaVision-28Q performed admirably, detecting 28 clinically important fusion gene transcripts quickly and consistently, including t(9;22) [BCR-ABL1], t(15;17) [PML-RARA], and inv(16) [CBFB-MYH11]. The assay was found to be highly sensitive and specific, with a faster turnaround time than HemaVision-28N. Its workflow reduced the need for labor-intensive stages such as gel electrophoresis, lowering the danger of contamination and making it an affordable and viable option for regular clinical diagnostics. In contrast, the HemaVision-28N assay, which provided thorough exon-level analysis of fusion genes, was time-consuming and required more technical knowledge. The study's findings emphasize the HemaVision-28Q kit as a dependable diagnostic option for acute leukemia, especially in clinical settings where speed and efficiency are critical
- PublicationEvaluation of the effects of kaffir lime and lemon myrtle essential oils on the digestive vacuole of plasmodium falciparum(2025-01)Malaria is a severe and fatal disease caused by Plasmodium spp. and remains one of the leading global causes of morbidity and mortality. The emergence of drug- resistance P. falciparum in various countries has necessitated an effort to discover new antimalarial drugs targeting different pathways. Medicinal plants have been a fundamental part of traditional medicine for centuries. Natural compounds extracted from these plants have shown great promise in serving as lead candidates for drug development. Despite this, research on the effects of kaffir lime and lemon myrtle essential oils on the digestive vacuole of P. falciparum remains largely unexplored. Therefore, this study aimed to fill this knowledge gap by investigating the antimalarial activity of kaffir lime and lemon myrtle essential oils. The antimalarial potential of the kaffir lime and lemon myrtle against the chloroquine-sensitive strain (3D7) of P. falciparum was assessed by using in vitro antimalarial assay. The kaffir lime and lemon myrtle essential oils demonstrated weak or no antimalarial activity with IC50 values of 150.6 μg/mL and 273.5 μg/mL, respectively. Additionally, the treatment with different concentrations of kaffir lime and lemon myrtle essential oil showed no changes on the digestive vacuole pH. This study revealed that the pH of the digestive vacuole treated with kaffir lime and lemon myrtle essential oils are stable and comparable to the untreated control. This suggests that these essential oils do not alters the digestive vacuole pH of P. falciparum
- PublicationAnxiety, depression and coping strategies among parents of children with autism at zayed higher organization for-people of determination, Abu Dhabi(2025-09)Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder causing social communication impairments, restricted interests, and repetitive behaviors. A global prevalence of one in every 100 children presents lifelong challenges for affected families. Parents often experience psychological stress due to caregiving issues, inadequate support systems, and societal stigma, especially in Arab countries. This study aims to assess the levels of anxiety, depression, and coping strategies as well as determining factors associated with depression, anxiety, and coping strategies among parents of autism spectrum disorder (ASD) children at the Zayed Higher Organization for People of Determination, Abu Dhabi. This cross-sectional study involved 200 parents of children with autism spectrum disorder (ASD), recruited through convenience sampling. Data was collected by inviting available and willing parents of children with ASD at the Zayed Higher Organization in Abu Dhabi to participate in the study by completing an online self-administered questionnaire. The data was collected using a validated online self-administered questionnaire consisting of the hospital anxiety and depression scale (HADS) to measure anxiety and depression and the Ways of Coping Questionnaire (WOC) to measure coping methods. Data were analyzed using SPSS version 27 with a chi-square test for categorical data. The results show that the majority of the respondents had moderate anxiety levels n=72 (36%) and high depression levels (48.5%), and most of the respondents were moderate-level copers (81.3%). There was no significant association between the respondents' coping levels and their levels of depression and anxiety. The analysis identifies several factors that are significantly associated with anxiety levels: education level (p = 0.011), employment (p = 0.028), marital status (p = 0.022), number of children (p = 0.001), and children’s sex (p = 0.028). In addition to the children age/year (p = 0.010). Depression levels are associated with marital status (p = 0.035) and the children’s method of education (p = 0.002). For coping levels, the factors associated are the respondent's age (p = 0.019), marital status (p = 0.009), and the children’s method of education (p = 0.002). In addition, Income (p = <0.001) and Children age (p = <0.001). In conclusion, understanding the experiences and concerns of parents can guide the provision of services that help parents identify needs related to the challenges of raising children with autism. It suggests that nursing professionals, psychoeducation, collaboration between practitioners and families, and future research should involve a large population and awareness-raising programs. The practical implications of these findings highlight the need for targeted psychological support, counseling services, and family-centered interventions, especially for parents with limited education, low income, and those managing older children. Healthcare professionals, particularly nurses, should be trained to provide culturally sensitive psychoeducation and early emotional support. Workplace flexibility, accessible educational resources for children with ASD, and marital support programs may help improve parental well-being. Future research should involve larger, more diverse populations and support awareness-raising programs at the community and institutional levels
- PublicationDevelopment and validation of a malnutrition risk assessment scale for chronic kidney disease (CKD) patients in shaanxi province, China(2025-01)Malnutrition remains a significant complication in Chronic Kidney Disease (CKD), contributing to poor clinical outcomes and reduced quality of life, yet effective tools for its early identification are limited. The current study aimed to develop and validate the Malnutrition Risk Assessment Scale (CKD-MRAS) tailored specifically for CKD patients. Conducted at Xi’an Provincial Hospital of Traditional Chinese Medicine in China, the study followed a multi-phase approach. In the first phase, initial items for the Malnutrition Knowledge, Attitude, and Practice (KAP) Scale and CKD-MRAS were formulated through semi-structured interviews (n=13). These initial items were refined using two rounds of the Delphi method, involving a panel of 15 experts. In the second phase, a pilot study involving 20 CKD patients was conducted to ensure clarity, feasibility, and relevance of the items before large-scale testing. Subsequently the Malnutrition KAP scale underwent validation in the first part, with CKD patients (n=152) participating in item analysis and exploratory factor analysis (EFA). Item analysis revealed the need to eliminate item K1 due to its low difficulty and discrimination index. EFA for the Attitude (A) and Practice (P) domains demonstrated factor loadings above the cut-off value of > 0.5, explaining 69.87% and 61.84% of the total variance, respectively. The scale exhibited strong internal consistency (Cronbach's alpha = 0.967, split-half reliability = 0.974). Confirmatory factor analysis (CFA) was conducted (n=151). The final 6-item model for the 'K' domain displayed good fit based on several fit indices (RMSEA (90%CI) = 0.070 (0.000, 0.124), CFI=0.978, TLI=0.963, SRMR=0.061). Similarly, the 9-item model for the 'A' domain and the 10-item model for the 'P' domain exhibited excellent fit indices. The final measurement model comprised 25 items. In the second part, multivariable logistic regression identified independent risk factors for malnutrition, including Knowledge [AOR 0.719 (0.529-0.978), p=0.035], Attitude [AOR 0.875 (0.826-0.927), p<0.001], Practice [AOR 0.895 (0.847-0.946), p<0.001], monthly per capita household income [AOR 4.658 (1.489-14.566), p=0.008)], appetite [AOR 3.575 (1.602-7.978), p=0.002], and gastrointestinal status [AOR 8.174 (3.622-18.448), p<0.001]. The CKD-MRAS achieved an area under the curve of 0.925 and an overall accuracy of 92.5%. In the third part, the prevalence of malnutrition among CKD patients was found to be 33.7%, with 40.7% at risk according to the CKD-MRAS. Additionally, substantial agreement was observed between the CKD-MRAS and Nutrition Risk Screening (NRS2002) (Kappa = 0.657, p < 0.001). Malnutrition risk demonstrated a negative correlation with various dimensions of quality of life (r value ranging from -0.386 to -0.722, p < 0.001). In conclusion, the CKD-MRAS is a reliable and valid tool for assessing malnutrition risk in CKD patients, offering an opportunity for early intervention to improve patient outcomes. Further studies should explore its application in diverse populations and settings.
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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.
- ItemMST 564 - Statistical Reliability - Oktober 2004(Universiti Sains Malaysia, 2004-10)
- ItemEffects Of Repetitive Uncontrolled Temperature Exposure On The Quality Of Packed Red Blood Cells(Universiti Sains Malaysia, 2019)Packed Red Blood Cells (PRBC) must be transfused within 30 minutes upon removal from blood refrigerator and the PRBC should not be hold in the ward where the storage temperature is not controlled. Untransfused blood which returned to the blood bank shall be discarded unless it is kept in an appropriate condition and temperature. Intermittent storage outside allowable temperature range often leads to destruction of the PRBC unit. This was a cross sectional study performed to determine the PRBC warming rates and the quality of PRBC upon repetitive exposure to uncontrolled temperature after 30 minutes and 4 hours. In this study four PRBC units (228 mL ± 37mL) collected from eligible volunteer subjects were equivalently split into two units, producing eight smaller units PRBC (±130mL) which then assigned into two groups; control and experimental group. Eight units of PRBC from both control and experimental group were tested on day 1, day 7, day 14 and day 35 of storage for haemoglobin level, haematocrit, haemolysis rate, potassium, lactate dehydrogenase (LDH), pH and sterility. The PRBC warming rate upon exposure to uncontrolled temperature were monitored and recorded. All PRBCs achieved desired quality requirement from national guideline from day 1 to day 35 for haematocrit, haemolysis rate, and sterility. However, none of the PRBC units met the standard requirement (>45g/unit) for haemoglobin starting day 14 to day 35. No significant changes observed for all PRBC’s quality over repetitive exposure to uncontrolled temperature in 35 days in experimental group (P<0.05). There was also no evidence of bacterial contamination in PRBC at the end of their shelf life.
- ItemSynthesis And Characterization Of Black Silicon By Silver-Assisted Chemical Etching For Solar Cell(Universiti Sains Malaysia, 2021-03)Crystalline silicon (c-Si) suffers from poor light absorption due to its indirect band gap and high reflection from its surface (about 35% in the visible region). This problem can be solved by texturing the surface of c-Si wafer to reduce its broadband reflection. Black silicon (b-Si) or nanotextured c-Si, has a huge potential for applications in solar cell due to its superior broadband light absorption within 300-1100 nm wavelength region. In this work, two-step metal-assisted chemical etching (MACE) is used to synthesize b-Si by combining low-annealing temperature of silver (Ag) film and short duration of etching of the c-Si wafer. For the b-Si fabrication, p-type (100) c-Si wafers are deposited with 15 nm Ag film using radio frequency (RF) sputtering process. Subsequently, the Ag film is annealed at low temperatures (200-230ᵒC) for 40 min in nitrogen (N2) ambient, producing Ag nanoparticles (NPs). Then, the c-Si wafers with the Ag NPs are etched in a solution containing hydrofluoric acid:hydrogen peroxide:deionized water (HF:H2O2:DI H2O) for a short duration (35-180 s). Effects of etching time, etchant volume ratio and annealing temperature towards surface morphological and optical properties by using atomic force microscope (AFM), field emission scanning electron microscope (FESEM) and UV-Vis-NIR (within 300-1100 nm wavelength region) of b-Si are then investigated. From the investigation, the b-Si with the lowest broadband reflection is produced by annealing at 230ᵒC for 40 min and etched for 70 s using HF:H2O2:DI H2O (1:5:10 by volume). The lowest reflection of the b-Si wafer is 3% at wavelength of 600 nm, with weighted average reflection (WAR) of 8%. The b-Si demonstrates average width and height of about 50-100 nm and 300-400 nm respectively for the nanotextures. For solar cell fabrication, the b-Si is diffused with phosphoric acid (H3PO4) and 2-butanol using temperatures between 850 to 950oC for 20 min to form front n+ emitter. The emitter is characterized using Hall effect measurement. Ag and aluminium (Al) are thermally evaporated on the front and rear surfaces respectively to form electrical contacts. From current-voltage measurement, the b-Si solar cells demonstrate short-circuit current density (Jsc) of 20 mA/cm2, open-circuit voltage (Voc) of 423 mV and fill factor (FF) of 25.4%. This corresponds to conversion efficiency (η) of 5.2%. On the other hand, the planar c-Si reference solar cells exhibit Jsc of 7 mA/cm2, Voc of 390 mV and FF of 21.7%. The low conversion efficiency of the solar cells is contributed by high shading loss due to the front metal fingers and poor quality of p-n junction formation.
- ItemMAT 122 - Persamaan Pembezaan - Mac 2005(Universiti Sains Malaysia, 2005-03)