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A pilot project on hospital-based universal newborn hearing screening: lessons learned

Mukari SZ, Tan KY, Abdullah A

Int J Pediatr Otorhinolaryngol, 2006 May;70(5):843-51.
PMID: 16246430

This paper reports the performance of a newly implemented hospital-based universal newborn hearing screening programme and the challenges to the effective implementation.
Determination of DPPH free radical scavenging activity: application of artificial neural networks

Musa KH, Abdullah A, Al-Haiqi A

Food Chem, 2016 Mar 1;194:705-11.
PMID: 26471610 DOI: 10.1016/j.foodchem.2015.08.038

A new computational approach for the determination of 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity (DPPH-RSA) in food is reported, based on the concept of machine learning. Trolox standard was mix with DPPH at different concentrations to produce different colors from purple to yellow. Artificial neural network (ANN) was trained on a typical set of images of the DPPH radical reacting with different levels of Trolox. This allowed the neural network to classify future images of any sample into the correct class of RSA level. The ANN was then able to determine the DPPH-RSA of cinnamon, clove, mung bean, red bean, red rice, brown rice, black rice and tea extract and the results were compared with data obtained using a spectrophotometer. The application of ANN correlated well to the spectrophotometric classical procedure and thus do not require the use of spectrophotometer, and it could be used to obtain semi-quantitative results of DPPH-RSA.
Adsorption, desorption, and mobility of metsulfuron methyl in Malaysian agricultural soils

Abdullah AR, Sinnakkannu S, Tahir NM

Bull Environ Contam Toxicol, 2001 Jun;66(6):762-9.
PMID: 11353379
The effect of signal grass (Brachiaria decumbens) on drug-metabolizing enzymes in sheep and comparison with normal cells

Khairi HM, Elsheikh HA, Salam Abdullah A

Vet Hum Toxicol, 2000 Aug;42(4):193-5.
PMID: 10928679

The effect of Brachiaria decumbens (signal grass) on drug-metabolizing enzymes was studied in sheep. After 14 d of grazing a pure signal grass pasture, significant declines were observed in hepatic aminopyrine N-demethylase and aniline 4-hydroxylase (phase I biotransformation) and in conjugative enzymes UDP-glucuronyltransferase and glutathione S-transferase. Kidney enzymes were significantly decreased except for UDP-glucuronyltransferase. Enzyme activities were also compared for normal sheep and cattle livers and kidneys. Lower activities were found in cattle, indicating that factors other than biotransformation are responsible for the clincial tolerance of cattle to B. decumbens toxicity.
Distribution of oil and grease and petroleum hydrocarbons in the Straits of Johor, peninsular Malaysia

Abdullah AR, Woon WC, Bakar RA

Bull Environ Contam Toxicol, 1996 Jul;57(1):155-62.
PMID: 8661474
Hydrocarbons in seawater and sediment from the west coast of Peninsular Malaysia

Abdullah AR, Tahir NM, Wei LK

Bull Environ Contam Toxicol, 1994 Oct;53(4):618-26.
PMID: 8000192
Neurological disorders in sheep during signal grass (Brachiaria decumbens) toxicity

Abdullah AS, Noordin MM, Rajion MA

Vet Hum Toxicol, 1989 Apr;31(2):128-9.
PMID: 2929118

Severe neurological dysfunction was observed in sheep 4 weeks after grazing on Signal grass (Brachiaria decumbens). These neurological disorders included the stamping of forelegs, star-gazing, incoordination, head-pressing against the fence and circling movements. Histologically, numerous vacuolations of various sizes were observed in the white matter of the brain giving rise to a spongy appearance.
Signal grass (Brachiaria decumbens) toxicity in sheep: changes in motility and pH of reticulo-rumen

Abdullah AS, Nordin MM, Rajion MA

Vet Hum Toxicol, 1988 Jun;30(3):256-8.
PMID: 3388753

In addition to generalized icterus, enlargement of the liver and severe photosensitization, signal grass (Brachiaria decumbens) toxicity also caused ruminal stasis and a decreased rumen pH in sheep. Ruminal stasis, which occurred within 3 weeks of grazing on this grass, may be the effect of the toxin produced in the rumen rather than a sequele of a decreased rumen pH. Animals were anorexic and the volume of their rumen content was very much reduced.
Fulltext The different faces of facial nerve schwannomas

Abdullah A, Mahmud MR, Sabir HA, Saim L

Med J Malaysia, 2003 Aug;58(3):450-3.
PMID: 14750390

Facial nerve schwannomas are rare benign tumors. The tumor can arise anywhere along the course of the facial nerve. The most common presentation for this tumor is a slowly progressive facial nerve paralysis. Sensorineural hearing loss (SNHL) and tinnitus are later symptoms. The symptoms and signs depend on the site of tumor along the nerve. We report three cases of facial nerve schwannomas with different clinical presentations. Appropriate management of a facial nerve schwannoma should be based on the site and extent of the tumor and status of the nerve function.
Fulltext Distinctive accuracy measurement of binary descriptors in mobile augmented reality

Tan SY, Arshad H, Abdullah A

PLoS One, 2019;14(1):e0207191.
PMID: 30605474 DOI: 10.1371/journal.pone.0207191

Mobile Augmented Reality (MAR) requires a descriptor that is robust to changes in viewing conditions in real time application. Many different descriptors had been proposed in the literature for example floating-point descriptors (SIFT and SURF) and binary descriptors (BRIEF, ORB, BRISK and FREAK). According to literature, floating-point descriptors are not suitable for real-time application because its operating speed does not satisfy real-time constraints. Binary descriptors have been developed with compact sizes and lower computation requirements. However, it is unclear which binary descriptors are more appropriate for MAR. Hence, a distinctive and efficient accuracy measurement of four state-of-the-art binary descriptors, namely, BRIEF, ORB, BRISK and FREAK were performed using the Mikolajczyk dataset and ALOI dataset to identify the most appropriate descriptor for MAR in terms of computation time and robustness to brightness, scale and rotation changes. The obtained results showed that FREAK is the most appropriate descriptor for MAR application as it able to produce an application that are efficient (shortest computation time) and robust towards scale, rotation and brightness changes.
Fulltext Quality of Service Class Identifier (QCI) radio resource allocation algorithm for LTE downlink

Mamman M, Hanapi ZM, Abdullah A, Muhammed A

PLoS One, 2019;14(1):e0210310.
PMID: 30682038 DOI: 10.1371/journal.pone.0210310

The increasing demand for network applications, such as teleconferencing, multimedia messaging and mobile TV, which have diverse requirements, has resulted in the introduction of Long Term Evolution (LTE) by the Third Generation Partnership Project (3GPP). LTE networks implement resource allocation algorithms to distribute radio resource to satisfy the bandwidth and delay requirements of users. However, the scheduling algorithm problem of distributing radio resources to users is not well defined in the LTE standard and thus considerably affects transmission order. Furthermore, the existing radio resource algorithm suffers from performance degradation under prioritised conditions because of the minimum data rate used to determine the transmission order. In this work, a novel downlink resource allocation algorithm that uses quality of service (QoS) requirements and channel conditions to address performance degradation is proposed. The new algorithm is formulated as an optimisation problem where network resources are allocated according to users' priority, whereas the scheduling algorithm decides on the basis of users' channel status to satisfy the demands of QoS. Simulation is used to evaluate the performance of the proposed algorithm, and results demonstrate that it performs better than do all other algorithms according to the measured metrics.
Fulltext Classification of botnet attacks in IoT smart factory using honeypot combined with machine learning

Lee S, Abdullah A, Jhanjhi N, Kok S

PeerJ Comput Sci, 2021;7:e350.
PMID: 33817000 DOI: 10.7717/peerj-cs.350

The Industrial Revolution 4.0 began with the breakthrough technological advances in 5G, and artificial intelligence has innovatively transformed the manufacturing industry from digitalization and automation to the new era of smart factories. A smart factory can do not only more than just produce products in a digital and automatic system, but also is able to optimize the production on its own by integrating production with process management, service distribution, and customized product requirement. A big challenge to the smart factory is to ensure that its network security can counteract with any cyber attacks such as botnet and Distributed Denial of Service, They are recognized to cause serious interruption in production, and consequently economic losses for company producers. Among many security solutions, botnet detection using honeypot has shown to be effective in some investigation studies. It is a method of detecting botnet attackers by intentionally creating a resource within the network with the purpose of closely monitoring and acquiring botnet attacking behaviors. For the first time, a proposed model of botnet detection was experimented by combing honeypot with machine learning to classify botnet attacks. A mimicking smart factory environment was created on IoT device hardware configuration. Experimental results showed that the model performance gave a high accuracy of above 96%, with very fast time taken of just 0.1 ms and false positive rate at 0.24127 using random forest algorithm with Weka machine learning program. Hence, the honeypot combined machine learning model in this study was proved to be highly feasible to apply in the security network of smart factory to detect botnet attacks.
Fulltext Serological response to Group A Streptococcus

Zainal Z, Jamal J, Abdullah A, Abdullah A

Family Practitioner, 1986;9(3):35-37.
Antioxidant Modulation of mTOR and Sirtuin Pathways in Age-Related Neurodegenerative Diseases

Abdullah A, Mohd Murshid N, Makpol S

Mol Neurobiol, 2020 Dec;57(12):5193-5207.
PMID: 32865663 DOI: 10.1007/s12035-020-02083-1

In the human body, cell division and metabolism are expected to transpire uneventfully for approximately 25 years. Then, secondary metabolism and cell damage products accumulate, and ageing phenotypes are acquired, causing the progression of disease. Among these age-related diseases, neurodegenerative diseases have attracted considerable attention because of their irreversibility, the absence of effective treatment and their relationship with social and economic pressures. Mechanistic (formerly mammalian) target of rapamycin (mTOR), sirtuin (SIRT) and insulin/insulin growth factor 1 (IGF1) signalling pathways are among the most important pathways in ageing-associated conditions, such as neurodegeneration. These longevity-related pathways are associated with a diversity of various processes, including metabolism, cognition, stress reaction and brain plasticity. In this review, we discuss the roles of sirtuin and mTOR in ageing and neurodegeneration, with an emphasis on their regulation of autophagy, apoptosis and mitochondrial energy metabolism. The intervention of neurodegeneration using potential antioxidants, including vitamins, phytochemicals, resveratrol, herbals, curcumin, coenzyme Q10 and minerals, specifically aimed at retaining mitochondrial function in the treatment of Alzheimer's disease, Parkinson's disease and Huntington's disease is highlighted.
Tocotrienols Activate Nrf2 Nuclear Translocation and Increase the Antioxidant- Related Hepatoprotective Mechanism in Mice Liver

Atia A, Alrawaiq NS, Abdullah A

Curr Pharm Biotechnol, 2021;22(8):1085-1098.
PMID: 32988349 DOI: 10.2174/1389201021666200928095950

BACKGROUND: The most common preparation of tocotrienols is the Tocotrienol-Rich Fraction (TRF). This study aimed to investigate whether TRF induced liver Nrf2 nuclear translocation and influenced the expression of Nrf2-regulated genes.
METHODS: In the Nrf2 induction study, mice were divided into control, 2000 mg/kg TRF and diethyl maleate treated groups. After acute treatment, mice were sacrificed at specific time points. Liver nuclear extracts were prepared and Nrf2 nuclear translocation was detected through Western blotting. To determine the effect of increasing doses of TRF on the extent of liver nuclear Nrf2 translocation and its implication on the expression levels of several Nrf2-regulated genes, mice were divided into 5 groups (control, 200, 500 and 1000 mg/kg TRF, and butylated hydroxyanisole-treated groups). After 14 days, mice were sacrificed and liver RNA was extracted for qPCR assay.
RESULTS: 2000 mg/kg TRF administration initiated Nrf2 nuclear translocation within 30 min, reached a maximum level of around 1 h and dropped to half-maximal levels by 24 h. Incremental doses of TRF resulted in dose-dependent increases in liver Nrf2 nuclear levels, along with concomitant dosedependent increases in the expressions of Nrf2-regulated genes.
CONCLUSION: TRF activated the liver Nrf2 pathway resulting in increased expression of Nrf2-regulated cytoprotective genes.
Fulltext Proteomic profiles of young adults with acute myocardial infarction.

Mohamed Bakrim N, Mohd Shah AS, Mohd. Shah ANS, A. Talib N, A.Rahman J, Muhamad Bunnori N, et al.

IIUM Medical Journal Malaysia, 2019;18(3):112-119.
MyJurnal

Proteomic profiling is essential in understanding the pathophysiological process of multifactorial diseases such as acute myocardial infarction (AMI). Despite the increasing incidence of AMI in young adults, proteomic-based study focusing on young AMI remains limited. This study aimed to examine the plasma proteomic profiles of young adults with AMI compared to control subjects. We also hope to identify disease-specific protein biomarkers that contribute to the development of AMI in the young. Methods:Pooled plasma protein from 10 AMI patients aged 18 to 45 years and 10 age, gender and race-matched volunteers were separated using two-dimensional electrophoresis (2-DE). The spots proteins were analysed using the PD Quest analysis software. The spots proteins that were found to have been expressed differently between the two groups were identified by Matrix Assisted Laser Desorption/Ionization Time of Flight (MALDI-TOF) Mass Spectrometry. Results:There were three differently expressed proteins namely Apolipoprotein AI (Apo AI), Apolipoprotein AIV (Apo AIV) and Haptoglobin (p < 0.05). The expressions of these proteins were found to be increased in young patients with AMI compared to control subjects. Conclusion: The up regulation of Apo AI, Apo AIV and Haptoglobin in AMI patients indicate their important roles in the development of atherosclerotic disease. Thus, Apo AI, Apo AIV and Haptoglobin are potential disease biomarkers for young AMI.
Fulltext Review of forensically important entomological specimens in the period of 1972 - 2002

Lee HL, Krishnasamy M, Abdullah AG, Jeffery J

Trop Biomed, 2004 Dec;21(2):69-75.
PMID: 16493401

Forensic entomological specimens received by the Unit of Medical Entomology, IMR., from hospitals and the police in Malaysia in the last 3 decades (1972 - 2002) are reviewed. A total of 448 specimens were received. From these, 538 identifications were made with the following results: Eighteen species of cyclorrphaga flies were identified consisting of Chrysomya megacephala (Fabricius) 215 cases (47.99%), Ch. rufifacies (Masquart) 132 (29.46%), Ch. villeneuvi Patton 10 (2.23%), Ch. nigripes Aubertin 7 (1.56%), Ch. bezziana Villeneuve 4 (0.89%), Ch. pinguis (Walker) 1 (0.22%), Chrysomya sp. 47 (10.49%), Sarcophaga sp. 28 (6.25%), Lucilia sp. 21 (4.69%), Hermetia sp. 15 (3.35%), He. illucens (Linnaeus) 1 (0.22%), Hemipyrellia ligurriens (Wiedemann) 3 (0.67%), Hemipyrellia sp. 2 (0.45%), Ophyra spinigera 1 (0.22%), Ophyra sp. 6 (1.34%), Calliphora sp. 24 (5.36%), Synthesiomyia nudiseta (Wulp) 1 (0.22%) and Eristalis sp. 1 (0.22%). Other non - fly insect specimens are Pthirus pubis (Linnaeus) (Pubic louse) 2 (0.45%) and Coleoptera (Beetles) 1 (0.22%). Ch. megacephala and Ch. rufifacies were the commonest species found in cadavers from different ecological habitats. Sy. nudiseta is an uncommon species, thus far found only on cadavers from indoors. Sy. nudiseta is reported for the second time in Peninsular Malaysia. A total of 329 cases (73.44%) had a single fly infestation, 109 cases (24.33%) had double fly infestation and 10 cases (2.23%) had triple fly infestation. Five cases (1.12%) had eggs and 3 cases (0.67%) had larval stages that were not identifiable. No arthropods were retrieved from cadavers in 8 cases (1.79%). In conclusion, although large number of fly species were found on human cadavers, the predominant species are still those of Chrysomya.
Fulltext A New Technique for Solving Tightrope Cutout during Acromioclavicular Joint Fixation: A Case Report

Ng BW, Abdullah AF, Nadarajah S

Malays Orthop J, 2017 Mar;11(1):57-59.
PMID: 28435576 MyJurnal DOI: 10.5704/MOJ.1703.003

Acromioclavicular joint (ACJ) dissociation is one of the common injuries affecting adults. The stability of ACJ largely depends on the integrity of acromioclavicular ligament, coracoclavicular ligament, capsule, trapezius muscle and deltoid muscle. The injury has been classified by Rockwood into six types and treatment options can be guided by the classification. TightRope fixation is one of the many surgical procedures available to address acromioclavicular joint separation. It consists of tensioning of a no. 5 Fibrewire suture secured at both ends to low-profile metallic buttons. Despite various advantages of using this technique, complications such as suture cut-out, clavicle fracture and suture failure have been documented. The author presents a case of a type III acromioclavicular joint dissociation treated with TightRope which suture cutout was noted intra-operatively. Decision to amend the fixation using a cut one-third tubular plate as an additional anchor for the metallic button on the clavicle was made. Patient's progress was evaluated using the University of California at Los Angeles Shoulder Score (UCLA Shoulder Score) and significant improvement was noted six months post operatively. We propose this technique as a solution to the encountered problem.
Fulltext Optimization of essential oil and Fucoxanthin extraction from Sargassum Binderi by Supercritical Carbon Dioxide (SC-CO2) extraction with Ethanol as co-solvent using Response Surface Methodology (RSM)

Jaswir, I., Noviendri, D., Salleh, H.M., Taher, M., Mohamed, F., Octavianti, F., et al.

International Food Research Journal, 2017;24(101):514-521.
MyJurnal

Supercritical carbon dioxide (SC-CO2) extraction of fucoxanthin is more advantageous over conventional solvent extraction as it is less toxic, less hazardous to the environment and preserves the bioactivity of fucoxanthin. A face-centered central composite design (FCCCD) based on response surface methodology (RSM) was employed for SC-CO2 extraction of oils and fucoxanthin from the brown seaweed Sargassum binderi, with ethanol as a co- solvent. Three independent parameters namely, extraction temperature (A: 40, 50, 60oC), pressure (B: 2900, 3625, 4350 psig and particle size (C: 90, 500 and 1000 µm) were investigated to optimize extraction oil yields (EOY) and fucoxanthin yields (FY). A regression model was developed, tested for quality of fit (R2) and expressed in the form of 3D response surface curve and 2D contour. The optimum extraction conditions were obtained at extraction temperature (A) 50oC, pressure (B) 3625 psig and particle size (C) 500 µm. Under these conditions, optimal EOY and FY were 10.04 mg/g and 3188.99 µg/g, respectively. The difference between the lowest and the highest response in EOY and FY were 5.44 – 10.04 mg/g and 2109.10 - 3188.90 µg/g, respectively. The lowest yields were identified at 60oC, 2900 psig and 1000 µm. The regression models generated showing interactions between the variables and EOY and FY response were significant as tested by ANOVA (p < 0.0005 and p < 0.0007, respectively) with high R2 values (0.9848 and 0.9829, respectively). Interactions between the parameters had a strong synergistic effect on EOY and FY values, as indicated by the 3D response surface curve and 2D contour. The experimental results matched the predicted results closely. This indicated the suitability of the models developed and the success of FCCCD under RSM in optimizing the S. binderi extraction conditions.
Catalytic fast pyrolysis of durian rind using silica-alumina catalyst: Effects of pyrolysis parameters

Tan YL, Abdullah AZ, Hameed BH

Bioresour Technol, 2018 Sep;264:198-205.
PMID: 29803811 DOI: 10.1016/j.biortech.2018.05.058

Silica-alumina catalyst was prepared and used in the catalytic fast pyrolysis of durian rind in a drop-type two-stage reactor. The effects of catalytic temperature (400 °C-600 °C) and catalyst-to-durian rind ratio (1:30-3:30) were evaluated. Bio-oil yield was increased with increased catalytic temperature due to considerable dehydration process, but it was reduced with high catalyst loading due to the overcracking of organics into light gases. Silica-alumina catalyst possessed good selectivity and the products changed according to the temperature. The major components in bio-oil were hydrocarbons, furan derivatives, and aromatic compounds at 400 °C, 500 °C, and 600 °C, respectively. The hydrogen and carbon contents of bio-oil were reduced with high catalyst loading due to the overcracking of organics, and the deoxygenation process became unfavorable. The silica-alumina catalyst worked well in catalytic fast pyrolysis of durian rind, and the condition may be adjusted based on the desired products.

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