Displaying publications 41 - 60 of 142 in total

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  1. Evaluation of heavy metals and environmental risk assessment in the Mangrove Forest of Kuala Selangor estuary, Malaysia
    ELTurk M, Abdullah R, Rozainah MZ, Abu Bakar NK
    Mar Pollut Bull, 2018 Nov;136:1-9.
    PMID: 30509789 DOI: 10.1016/j.marpolbul.2018.08.063
    This study was carried out to evaluate the distribution, enrichment and ecological risk of heavy metals (arsenic (As), zinc (Zn), manganese (Mn), copper (Cu) and lead (Pb)) concentration in Kuala Selangor estuary at the Kuala Selangor Nature Park. The results suggested that As and Pb in sediment were as high as the background value, suggesting the presence of anthropogenic contamination. The risk assessment of sediment Igeo, CD, and PERI, on the other hand, showed low risk of heavy metals in Kuala Selangor estuary. Meanwhile, risk assessment code (RAC) results showed that Mn, As and Zn presented medium to high level of environmental risk. The translocation factor and bioaccumulation factors of heavy metal concentration by mangrove vegetation showed a variety of trends, which indicates the different partitioning and uptake ability of heavy metal in the tissues of different mangrove species. Therefore, underscores the importance of preserving the high diversity of mangroves at securing the health and productivity of the coastal region. These results may play a critical role in facilitating decision makers in managing the sustainability of mangrove forests.
  2. Fulltext Anti-Enterococcus Faecalis, Cytotoxicity, Phytotoxicity, and Anticancer Studies on Clausena excavata Burum. f. (Rutaceae) Leaves
    Albaayit SFA, Maharjan R, Abdullah R, Noor MHM
    Biomed Res Int, 2021;2021:3123476.
    PMID: 33748267 DOI: 10.1155/2021/3123476
    BACKGROUND: Clausena excavata Burum. f. has long been applied in ethnomedicine for the treatment of various disorders like rhinitis, headache, cough, wound healing, fever, and detoxification. This study is aimed at investigating the antibacterial activity against Enterococcus faecalis ATCC 49532 using AlamarBlue assay and atomic force microscopy (AFM) as well as the cytotoxicity, anticancer, and phytotoxicity of C. excavata.

    METHOD: Bacterial cell viability was performed by using microplate AlamarBlue assay. Atomic force microscopy was used to determine morphological changes in the surface of bacterial cells. Cytotoxicity and phytotoxicity were determined by brine shrimp lethality and Lemna minor bioassay. Caco-2 (colorectal adenocarcinoma) cell line was used for the evaluation of the anticancer effects.

    RESULT: Among the fractions tested, ethyl acetate (EA) fraction was found to be active with minimum inhibitory concentration (MIC) of 750 μg/mL against E. faecalis, but other fractions were found to be insensitive to bacterial growth. Microscopically, the EA fraction-treated bacteria showed highly damaged cells with their cytoplasmic content scattered all over. The LC50 value of the EA fraction against brine shrimp was more than 1000 μg/mL showing the nontoxic nature of this fraction. Chloroform (CH), EA, and methanol (MOH) fractions of C. excavata were highly herbicidal at the concentration of 1000 μg/mL. EA inhibited Caco-2 cell line with an IC50 of 20 μg/mL.

    CONCLUSIONS: This study is the first to reveal anti-E. faecalis property of EA fraction of C. excavata leaves, natural herbicidal, and anticancer agents thus highlight the potential compound present in its leaf which needs to be isolated and tested against multidrug-resistant E. faecalis.

  3. Appraisal of data-driven techniques for predicting short-term streamflow in tropical catchment
    Yeoh KL, Puay HT, Abdullah R, Abd Manan TS
    Water Sci Technol, 2023 Jul;88(1):75-91.
    PMID: 37452535 DOI: 10.2166/wst.2023.193
    Short-term streamflow prediction is essential for managing flood early warning and water resources systems. Although numerical models are widely used for this purpose, they require various types of data and experience to operate the model and often tedious calibration processes. Under the digital revolution, the application of data-driven approaches to predict streamflow has increased in recent decades. In this work, multiple linear regression (MLR) and random forest (RF) models with three different input combinations are developed and assessed for multi-step ahead short-term streamflow predictions, using 14 years of hydrological datasets from the Kulim River catchment, Malaysia. Introducing more precedent streamflow events as predictor improves the performance of these data-driven models, especially in predicting peak streamflow during the high-flow event. The RF model (Nash-Sutcliffe efficiency (NSE): 0.599-0.962) outperforms the MLR model (NSE: 0.584-0.963) in terms of overall prediction accuracy. However, with the increasing lead-time length, the models' overall prediction accuracy on the arrival time and magnitude of peak streamflow decrease. These findings demonstrate the potential of decision tree-based models, such as RF, for short-term streamflow prediction and offer insights into enhancing the accuracy of these data-driven models.
  4. Risk assessment of aflatoxin B1 in herbal medicines and plant food supplements marketed in Malaysia using margin of exposure and RISK21 approaches
    Ab Dullah SS, Sabran MR, Hasiah AH, Abdullah R
    Genes Environ, 2023 Nov 23;45(1):31.
    PMID: 37993956 DOI: 10.1186/s41021-023-00286-1
    Aflatoxin B1 (AFB1) is a mycotoxin produced by several species of Aspergillus fungi which can cause liver cancer in animals and humans. This study aims to perform the risk assessment of AFB1 in herbal medicines and plant food supplements (PFS) in Malaysian market. A total of 31 herbal medicines and PFS were purchased through online platforms and over the counter using a targeted sampling strategy. Of 31 samples analysed using the ELISA method, 25 (80.6%) were contaminated with AFB1 at levels ranged from 0.275 to 13.941 μg/kg. The Benchmark Dose Lower Confidence level of 10 (BMDL10) of 63.46 ng/kg bw/day and the estimated dietary intake of the adult population ranged from 0.006 to 10.456 ng/kg bw/day were used to calculate the Margin of Exposure (MOE). The MOEs for 24 (96%) out of the 25 positive samples were lower than 10,000. The RISK21 matrix revealed that AFB1 exposure levels from herbal medicines and PFS differed greatly over the world. The calculated population risk of acquiring liver cancer from AFB1 exposure ranged from 0 to 0.261 cancers/100,000 populations/year and accounted for an estimated percentage of liver cancer incidence ranged from 0.002 to 4.149%. This study revealed a moderate risk of liver cancer attributable to AFB1 from herbal medicine and PFS among Malaysian populations and emphasised an urgency for risk management actions.
  5. Fulltext Exploration of vulnerability factors of digital hoarding behavior among university students and the moderating role of maladaptive perfectionism
    Zaremohzzabieh Z, Abdullah H, Ahrari S, Abdullah R, Md Nor SM
    Digit Health, 2024;10:20552076241226962.
    PMID: 38298527 DOI: 10.1177/20552076241226962
    In light of the rapidly evolving digital landscape, there is an increasing need to explore digital hoarding behavior. This need is driven by concerns regarding its intricate psychological foundations and its impact on individuals within our technology-centric society. This research investigates the influence of various factors, including the fear of missing out, emotional attachment, information overload, and decision fatigue, on digital hoarding behaviors among university students in Iran. Additionally, the study examines the moderating role of maladaptive perfectionism in these relationships. The study involved 275 university students (mean age = 21.62 years; standard deviation = 2.28 years; 65.6% female) selected from four universities in Iran. The data were analyzed using partial least squares structural equation modeling (PLS-SEM). The results revealed that the fear of missing out, emotional attachment, information overload, and decision fatigue significantly predict university students' digital hoarding behavior. Moreover, the findings highlighted the moderating effect of maladaptive perfectionism on the association between emotional attachment and digital hoarding behavior. This suggests that individuals with higher levels of maladaptive perfectionism exhibit amplified digital hoarding tendencies when emotionally attached to their digital data. This study provides a deeper understanding of the relationship between psychological factors and digital hoarding tendencies. These findings have practical implications for educational institutions and mental health professionals, as they can help in developing targeted strategies and interventions to manage digital hoarding behavior in university freshmen and promote healthier digital habits.
  6. Fulltext Evaluation of anti-methicillin-resistant Staphylococcus aureus property of zerumbone
    Fadhel Abbas Albaayit S, Maharjan R, Abdullah R, Hezmee Mohd Noor M
    J Appl Biomed, 2022 Feb 11.
    PMID: 35170271 DOI: 10.32725/jab.2022.002
    CONTEXT AND OBJECTIVE: Zerumbone has been reported to exert anti-microbial effects, but the mechanism by which the compound exerts its action is not known. Thus, this study aimed to investigate the mechanism of action of zerumbone against methicillin-resistance Staphylococcus aureus (MRSA), using the atomic force microscopy (AFM), scanning electron microscopy (SEM), and flow cytometry techniques.

    METHODS: MRSA (NCTC 13277) cell viability was determined using the microplate AlamarBlue assay. AFM and SEM were used to determine the morphology of zerumbone-treated MRSA cells. Flow cytometric analysis was used to determine the effect of zerumbone on bacterial membrane permeability and membrane potential, using the propidium iodide (PI) staining method, membrane potential-sensitive fluorescence probe, and DiBAC4(3) dye. DCFDA dye was used to determine the generation of reactive oxygen species (ROS) by MRSA.

    RESULTS: Zerumbone significantly inhibited MRSA growth with a minimum inhibitory concentration (MIC) of 125 µg/ml. The AFM analysis showed that zerumbone caused leakage of cytoplasmic content from the bacterial cells. Ultrastructure analysis showed small colonies of the bacteria with pores on the membrane surface. There were increases in zerumbone-treated MRSA PI and DiBAC4(3) fluorescence, indicating an increase in cell membrane permeability and a decrease in membrane potential that culminated in the loss of membrane structural integrity and bacterial death. Based on DCFDA dye analysis, zerumbone also reduced ROS production by MRSA.

    CONCLUSIONS: Zerumbone exerts anti-MRSA effects by causing membrane depolarization, increasing membrane permeability, and finally disrupting cell membrane and bacterial killing.

  7. Fulltext Evaluation of Antioxidant Activity and Acute Toxicity of Clausena excavata Leaves Extract
    Albaayit SF, Abba Y, Abdullah R, Abdullah N
    Evid Based Complement Alternat Med, 2014;2014:975450.
    PMID: 25610488 DOI: 10.1155/2014/975450
    Clausena excavata (Lour.), locally known as "Kemantu hitam," is a common plant in Malaysian folklore medicine. This study evaluated the antioxidant properties of the solvent extracts of C. excavata leaves and determined the acute toxicity of methanolic extract C. excavata (MECE) leaves in Sprague-Dawley rats. Harvested leaves were dried and subjected to solvent extraction using petroleum ether, chloroform, ethyl acetate and methanol in succession. The antioxidant activity of each extract was determined using the ferric-reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picryl dihydrazyl (DPPH) radical scavenging activity. The total phenolic content (TPC) and total flavonoids content (TFC) were estimated by Folin-Ciocalteu and ethanolic aluminium chloride method, respectively. The chloroform extract was found to be highest in flavonoid content, while the methanolic extract showed the highest TPC and antioxidant activity. There was no mortality in rats treated with MECE leaves even at a high dose of 5000 mg/kg body weight. However, the MECE leaves produced mild to moderate pathological changes in the liver and kidneys, shown by mild degenerative changes and leucocyte infiltration. The extract did not affect the haematological parameters or relative weights of the liver or kidneys. Overall, the MECE leaves have potent antioxidant activity and are presumed safe to be used orally as health-promoting product at low to moderate doses.
  8. Carbohydrate polymers-based surface modified nano delivery systems for enhanced target delivery to colon cancer - A review
    Ibrahim IAA, Alzahrani AR, Alanazi IM, Shahzad N, Shahid I, Falemban AH, et al.
    Int J Biol Macromol, 2023 Dec 31;253(Pt 2):126581.
    PMID: 37652322 DOI: 10.1016/j.ijbiomac.2023.126581
    Carbohydrate polymers-based surface-modified nano-delivery systems have gained significant attention in recent years for enhancing targeted delivery to colon cancer. These systems leverage carbohydrate polymers' unique properties, such as biocompatibility, biodegradability, and controlled release. These properties make them suitable candidates for drug delivery applications. Nano-delivery systems loaded with bioactive compounds are well-studied for targeted colorectal cancer delivery. However, those drugs' target reach is still limited in various nano-delivery systems. To overcome this limitation, surface modification of nanoparticles with carbohydrate polymers like chitosan, pectin, alginate, and guar gum showed enhanced target-reaching capacity along with enhanced anticancer efficacy. Recently, a chitosan-decorated PLGA nanoparticle was constructed with tannic acid and vitamin E and showed long-term release of specific targets along with higher anticancer efficacy. Similarly, Chitosan-conjugated glucuronic acid-coated silica nanoparticles loaded with capecitabine were studied against colon cancer and found to be the pH-responsive controlled release of capecitabine with higher anticancer efficacy. Surface-modified carbohydrate polymers have promising potential for improving colon cancer target delivery. By leveraging the unique properties of these polymers, such as surface modification, pH responsiveness, mucoadhesion, controlled drug release, and combination therapy, researchers are working toward developing more effective and targeted treatment strategies for colon cancer.
  9. Chitosan biopolymer functionalized with graphene oxide and titanium dioxide with Escin metallic nanocomposites for anticancer potential against colon cancer
    Ibrahim IAA, Alzahrani AR, Alanazi IM, Shahzad N, Shahid I, Falemban AH, et al.
    Int J Biol Macromol, 2023 Dec 31;253(Pt 7):127334.
    PMID: 37820908 DOI: 10.1016/j.ijbiomac.2023.127334
    Our study produced GO-TiO2-chitosan-escin nanocomposites (GTCEnc), characterized them using physical and biological methods, and evaluated their potential as cancer treatment candidates. Standard protocols were used to produce GTCEnc. Nanocomposites are created using XRD, FTIR, UV-Vis, and PL spectroscopy analysis. The morphology and ultrastructure of nanocomposites were investigated using SEM and TEM. Nanocomposites containing TiO2, GO, chitosan, and escin nanostructures were characterized using diffraction, microscopy, and spectroscopy; the antimicrobial activity of GTCEnc was investigated. Various methods were used to test the anticancer activity of GTCEnc against COLO 205 cell lines, including MTT, EtBr/AO, DAPI, JC-1, Annexin-V/FITC, cell cycle analysis, and activation of pro-apoptotic markers, such as caspase-3, -8, and -9. The nanocomposites were cytotoxic to COLO 205 cells, with an IC50 of 22.68 μg/mL, but not to 293T cells. In cells treated with nanomaterials, cytotoxicity, nuclear damage, apoptosis induction, and free radical production were significantly increased. Our finding suggests that GTCEnc has potent anticancer and antibacterial activity in vitro because of its unique nanocomposite properties and antibacterial and anticancer activity in vitro. Additional research is required to understand the clinical efficacy of these nanocomposites.
  10. Fulltext Synthesis and Characterization of Graphene Oxide/Polyethylene Glycol/Folic Acid/Brucine Nanocomposites and Their Anticancer Activity on HepG2 Cells
    Ibrahim IAA, Alzahrani AR, Alanazi IM, Shahzad N, Shahid I, Falemban AH, et al.
    Int J Nanomedicine, 2024;19:1109-1124.
    PMID: 38344441 DOI: 10.2147/IJN.S445206
    BACKGROUND: Liver cancer is the sixth most prevalent form of cancer and the second major cause of cancer-associated mortalities worldwide. Cancer nanotechnology has the ability to fundamentally alter cancer treatment, diagnosis, and detection.

    OBJECTIVE: In this study, we explained the development of graphene oxide/polyethylene glycol/folic acid/brucine nanocomposites (GO/PEG/Bru-FA NCs) and evaluated their antimicrobial and anticancer effect on the liver cancer HepG2 cells.

    METHODOLOGY: The GO/PEG/Bru-FA NCs were prepared using the co-precipitation technique and characterized using various techniques. The cytotoxicity of the GO/PEG/Bru-FA NCs was tested against both liver cancer HepG2 and non-malignant Vero cells using an MTT assay. The antimicrobial activity of the GO/PEG/Bru-FA NCs was tested against several pathogens using the well diffusion technique. The effects of GO/PEG/Bru-FA NCs on endogenous ROS accumulation, apoptosis, and MMP levels were examined using corresponding fluorescent staining assays, respectively. The apoptotic protein expressions, such as Bax, Bcl-2, and caspases, were studied using the corresponding kits.

    RESULTS: The findings of various characterization assays revealed the development of GO/PEG/Bru-FA NCs with face-centered spherical morphology and an agglomerated appearance with an average size of 197.40 nm. The GO/PEG/Bru-FA NCs treatment remarkably inhibited the growth of the tested pathogens. The findings of the MTT assay evidenced that the GO/PEG/Bru-FA NCs effectively reduced the HepG2 cell growth while not showing toxicity to the Vero cells. The findings of the fluorescent assay proved that the GO/PEG/Bru-FA NCs increased ROS generation, reduced MMP levels, and promoted apoptosis in the HepG2 cells. The levels of Bax, caspase-9, and -3 were increased, and Bcl-2 was reduced in the GO/PEG/Bru-FA NCs-treated HepG2 cells.

    CONCLUSION: The results of this work demonstrate that GO/PEG/Bru-FA NCs suppress viability and induce apoptosis in HepG2 cells, indicating their potential as an anticancer candidate.

  11. Fulltext Therapeutic strategy of biological macromolecules based natural bioactive compounds of diabetes mellitus and future perspectives: A systematic review
    Shahzad N, Alzahrani AR, Aziz Ibrahim IA, Shahid I, Alanazi IM, Falemban AH, et al.
    Heliyon, 2024 Jan 30;10(2):e24207.
    PMID: 38298622 DOI: 10.1016/j.heliyon.2024.e24207
    High blood glucose levels are a hallmark of the metabolic syndrome known as diabetes mellitus. More than 600 million people will have diabetes by 2045 as the global prevalence of the disease continues to rise. Contemporary antidiabetic drugs reduce hyperglycemia and its consequences. However, these drugs come with undesirable side effects, so it's encouraging that research into plant extracts and bioactive substances with antidiabetic characteristics is on the rise. Natural remedies are preferable to conventional anti-diabetic drugs since they are safer for the body, more affordable and have fewer potential adverse effects. Biological macromolecules such as liposomes, niosomes, polymeric nanoparticles, solid lipid nanoparticles, nanoemulsions and metallic nanoparticles are explored in this review. Current drug restrictions have been addressed, and the effectiveness of plant-based antidiabetic therapies has enhanced the merits of these methods. Plant extracts' loading capacity and the carriers' stability are the primary obstacles in developing plant-based nanocarriers. Hydrophilic, hydrophobic, and amphiphilic drugs are covered, and a brief overview of the amphipathic features of liposomes, phospholipids, and lipid nanocarriers is provided. Metallic nanoparticles' benefits and attendant risks are highlighted to emphasize their efficiency in treating hyperglycemia. Researchers interested in the potential of nanoparticles loaded with plant extracts as antidiabetic therapeutics may find the current helpful review.
  12. Anise (Pimpinella anisum L.) attenuates azoxymethane-induced colorectal cancer by antioxidant, anti-inflammatory, and anti-apoptotic pathways in rats
    Almaimani G, Jabbar AAJ, Ibrahim IAA, Alzahrani AR, Bamagous GA, Almaimani RA, et al.
    Environ Sci Pollut Res Int, 2024 Jan;31(3):4439-4452.
    PMID: 38103135 DOI: 10.1007/s11356-023-31349-z
    Herbal medicine is one of the most common fields explored for combating colon cancers, and Pimpinella anisum L. seeds (PAS) have been utilized widely as medicinal agents because of their increased essential oil (trans-anethole) contents. In this essence, our study investigates the toxic effect and chemoprotective potentials of PAS against azoxymethane (AOM)-induced colon cancer in rats. The toxicity trial for PAS conducted by clustering fifteen rats into three groups (five rats each): A, normal control had 10% Tween 20; B, ingested with 2 g/kg PAS; and C, supplemented with 4 g/kg PAS. The in vivo cancer trial was performed by using 30 rats (Sprague-Dawley) that were randomly adapted in five steel cages (six rats each): group A, normal controls received two subcutaneous injections of normal saline 0.09% and ingested orally 10% Tween 20; groups B-E, rats received two injections of 15 mg/kg of azoxymethane (AOM) subcutaneously in 2 weeks and treated orally with 10% Tween 20 (group B) or intraperitoneal injection of 5-fluorouracil (35 mg/kg) (group C), or orally given 200 mg/kg PAS (group D) and 400 mg/kg PAS (group E) for 8 weeks. After the scarification of rats, the colon tissues were dissected for gross and histopathological evaluations. The acute toxicity trial showed the absence of any toxic signs in rats even after 14 days of ingesting 4 g/kg of PAS. The chemoprotective experiment revealed significant inhibitory potentials (65.93%) of PAS (400 mg/kg) against aberrant crypto foci incidence that could be correlated with its positive modulation of the immunohistochemically proteins represented by a significant up-regulation of the Bax protein and a decrease of the Bcl-2 protein expressions in colon tissues. Furthermore, PAS-treated rats had notably lower oxidative stress in colon tissues evidenced by decreased MDA levels and increased antiradical defense enzymes (SOD, CAT, and GPx). The outcomes suggest 400 mg/kg PAS as a viable additive for the development of potential pharmaceuticals against colorectal cancer.
  13. Fulltext Binding mode analysis of zerumbone to key signal proteins in the tumor necrosis factor pathway
    Fatima A, Abdul AB, Abdullah R, Karjiban RA, Lee VS
    Int J Mol Sci, 2015 Jan 26;16(2):2747-66.
    PMID: 25629232 DOI: 10.3390/ijms16022747
    Breast cancer is the second most common cancer among women worldwide. Several signaling pathways have been implicated as causative and progression agents. The tumor necrosis factor (TNF) α protein plays a dual role in promoting and inhibiting cancer depending largely on the pathway initiated by the binding of the protein to its receptor. Zerumbone, an active constituent of Zingiber zerumbet, Smith, is known to act on the tumor necrosis factor pathway upregulating tumour necrosis factor related apoptosis inducing ligand (TRAIL) death receptors and inducing apoptosis in cancer cells. Zerumbone is a sesquiterpene that is able to penetrate into the hydrophobic pockets of proteins to exert its inhibiting activity with several proteins. We found a good binding with the tumor necrosis factor, kinase κB (IKKβ) and the Nuclear factor κB (NF-κB) component proteins along the TNF pathway. Our results suggest that zerumbone can exert its apoptotic activities by inhibiting the cytoplasmic proteins. It inhibits the IKKβ kinase that activates the NF-κB and also binds to the NF-κB complex in the TNF pathway. Blocking both proteins can lead to inhibition of cell proliferating proteins to be downregulated and possibly ultimate induction of apoptosis.
  14. Fulltext Thymoquinone-loaded nanostructured lipid carrier exhibited cytotoxicity towards breast cancer cell lines (MDA-MB-231 and MCF-7) and cervical cancer cell lines (HeLa and SiHa)
    Ng WK, Saiful Yazan L, Yap LH, Wan Nor Hafiza WA, How CW, Abdullah R
    Biomed Res Int, 2015;2015:263131.
    PMID: 25632388 DOI: 10.1155/2015/263131
    Thymoquinone (TQ) has been shown to exhibit antitumor properties. Thymoquinone-loaded nanostructured lipid carrier (TQ-NLC) was developed to improve the bioavailability and cytotoxicity of TQ. This study was conducted to determine the cytotoxic effects of TQ-NLC on breast cancer (MDA-MB-231 and MCF-7) and cervical cancer cell lines (HeLa and SiHa). TQ-NLC was prepared by applying the hot high pressure homogenization technique. The mean particle size of TQ-NLC was 35.66 ± 0.1235 nm with a narrow polydispersity index (PDI) lower than 0.25. The zeta potential of TQ-NLC was greater than -30 mV. Polysorbate 80 helps to increase the stability of TQ-NLC. Differential scanning calorimetry showed that TQ-NLC has a melting point of 56.73°C, which is lower than that of the bulk material. The encapsulation efficiency of TQ in TQ-NLC was 97.63 ± 0.1798% as determined by HPLC analysis. TQ-NLC exhibited antiproliferative activity towards all the cell lines in a dose-dependent manner which was most cytotoxic towards MDA-MB-231 cells. Cell shrinkage was noted following treatment of MDA-MB-231 cells with TQ-NLC with an increase of apoptotic cell population (P < 0.05). TQ-NLC also induced cell cycle arrest. TQ-NLC was most cytotoxic towards MDA-MB-231 cells. It induced apoptosis and cell cycle arrest in the cells.
  15. Fulltext Development of a decision support system for analysis and solutions of prolonged standing in the workplace
    Halim I, Arep H, Kamat SR, Abdullah R, Omar AR, Ismail AR
    Saf Health Work, 2014 Jun;5(2):97-105.
    PMID: 25180141 DOI: 10.1016/j.shaw.2014.04.002
    BACKGROUND: Prolonged standing has been hypothesized as a vital contributor to discomfort and muscle fatigue in the workplace. The objective of this study was to develop a decision support system that could provide systematic analysis and solutions to minimize the discomfort and muscle fatigue associated with prolonged standing.

    METHODS: The integration of object-oriented programming and a Model Oriented Simultaneous Engineering System were used to design the architecture of the decision support system.

    RESULTS: Validation of the decision support system was carried out in two manufacturing companies. The validation process showed that the decision support system produced reliable results.

    CONCLUSION: The decision support system is a reliable advisory tool for providing analysis and solutions to problems related to the discomfort and muscle fatigue associated with prolonged standing. Further testing of the decision support system is suggested before it is used commercially.

  16. Fulltext Cytotoxic effects of Mangifera indica L. kernel extract on human breast cancer (MCF-7 and MDA-MB-231 cell lines) and bioactive constituents in the crude extract
    Abdullah AS, Mohammed AS, Abdullah R, Mirghani ME, Al-Qubaisi M
    BMC Complement Altern Med, 2014;14:199.
    PMID: 24962691 DOI: 10.1186/1472-6882-14-199
    Waterlily Mango (Mangifera indica L.) is thought to be antioxidant-rich, conferred by its functional phytochemicals.
  17. Comparison of in vitro developmental competence of cloned caprine embryos using donor karyoplasts from adult bone marrow mesenchymal stem cells vs ear fibroblast cells
    Kwong PJ, Nam HY, Wan Khadijah WE, Kamarul T, Abdullah RB
    Reprod. Domest. Anim., 2014 Apr;49(2):249-53.
    PMID: 24456113 DOI: 10.1111/rda.12262
    The aim of this study was to produce cloned caprine embryos using either caprine bone marrow-derived mesenchymal stem cells (MSCs) or ear fibroblast cells (EFCs) as donor karyoplasts. Caprine MSCs were isolated from male Boer goats of an average age of 1.5 years. To determine the pluripotency of MSCs, the cells were induced to differentiate into osteocytes, chondrocytes and adipocytes. Subsequently, MSCs were characterized through cell surface antigen profiles using specific markers, prior to their use as donor karyoplasts for nuclear transfer. No significant difference (p > 0.05) in fusion rates was observed between MSCs (87.7%) and EFCs (91.3%) used as donor karyoplasts. The cleavage rate of cloned embryos derived with MSCs (87.0%) was similar (p > 0.05) to those cloned using EFCs (84.4%). However, the in vitro development of MSCs-derived cloned embryos (25.3%) to the blastocyst stage was significantly higher (p < 0.05) than those derived with EFCs (20.6%). In conclusion, MSCs could be reprogrammed by caprine oocytes, and production of cloned caprine embryos with MSCs improved their in vitro developmental competence, but not in their fusion and cleavage rate as compared to cloning using somatic cells such as EFCs.
  18. Research and development of transgenic plants in Malaysia: an example from an Asian developing country
    Hashim M, Osman M, Abdullah R, Pillai V, Abu Bakar UK, Hashim H, et al.
    Food Nutr Bull, 2002 Dec;23(4):367-75.
    PMID: 16619743
    In 2000, agriculture contributed 13% to the national gross domestic product of Malaysia. The country of 23 million people has created a competitive program coordinated by the Ministry of Science, Technology and the Environment, research institutions, and universities to undertake biotechnology research in several areas. Intensified research efforts are under way on oil palm, rubber, rice, papaya, and orchids. Although the most progress has been made in rice and papaya, no transgenic crop is ready for field trials. Nonetheless, preliminary steps have been taken to prepare for the trials, and detailed testing protocols are being developed.
  19. Comparison of tamoxifen with edible seaweed (Eucheuma cottonii L.) extract in suppressing breast tumor
    Shamsabadi FT, Khoddami A, Fard SG, Abdullah R, Othman HH, Mohamed S
    Nutr Cancer, 2013;65(2):255-62.
    PMID: 23441613 DOI: 10.1080/01635581.2013.756528
    The tropical edible red seaweed (Eucheuma cottonii L.) is rich in nutrients and polyphenolic compounds that may suppress cancer through its antioxidant and antiproliferative properties. The study reports on rat mammary tumor suppression and tissue antioxidant status modulation by E. cottonii ethanol extract (ECE). The effect of orally administered ECE (100 mg/kg body-weight) was compared with that of tamoxifen (10 mg/kg body-weight). Rat was induced to develop mammary tumor with subcutaneous injection of LA-7 cells (6 × 10(6) cells/rat). The ECE was more effective than tamoxifen in suppressing tumor growth (27%), improving tissues (plasma, liver, and kidney) malondialdehyde concentrations, superoxide dismutase activity and erythrocyte glutathione concentrations (P < 0.05). Unlike tamoxifen, the ECE displayed little toxicity to the liver and kidneys. The ECE exhibited strong anticancer effect with enzyme modulating properties, suggesting its potential as a suppressing agent for mammary gland tumor.
  20. Fulltext Monte Carlo dose calculation in dental amalgam phantom
    Aziz MZ, Yusoff AL, Osman ND, Abdullah R, Rabaie NA, Salikin MS
    J Med Phys, 2015 Jul-Sep;40(3):150-5.
    PMID: 26500401 DOI: 10.4103/0971-6203.165080
    It has become a great challenge in the modern radiation treatment to ensure the accuracy of treatment delivery in electron beam therapy. Tissue inhomogeneity has become one of the factors for accurate dose calculation, and this requires complex algorithm calculation like Monte Carlo (MC). On the other hand, computed tomography (CT) images used in treatment planning system need to be trustful as they are the input in radiotherapy treatment. However, with the presence of metal amalgam in treatment volume, the CT images input showed prominent streak artefact, thus, contributed sources of error. Hence, metal amalgam phantom often creates streak artifacts, which cause an error in the dose calculation. Thus, a streak artifact reduction technique was applied to correct the images, and as a result, better images were observed in terms of structure delineation and density assigning. Furthermore, the amalgam density data were corrected to provide amalgam voxel with accurate density value. As for the errors of dose uncertainties due to metal amalgam, they were reduced from 46% to as low as 2% at d80 (depth of the 80% dose beyond Zmax) using the presented strategies. Considering the number of vital and radiosensitive organs in the head and the neck regions, this correction strategy is suggested in reducing calculation uncertainties through MC calculation.
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