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Fulltext Removal of Cationic Dyes by Iron Modified Silica/Polyurethane Composite: Kinetic, Isotherm and Thermodynamic Analyses, and Regeneration via Advanced Oxidation Process

Ahmad A, Jamil SNAM, Choong TSY, Abdullah AH, Faujan NH, Adeyi AA, et al.

Polymers (Basel), 2022 Dec 10;14(24).
PMID: 36559783 DOI: 10.3390/polym14245416

Emerging dye pollution from textile industrial effluents is becoming more challenging for researchers worldwide. The contamination of water by dye effluents affects the living organisms in an ecosystem. Methylene blue (MB) and malachite green (MG) are soluble dyes with a high colour intensity even at low concentration and are hazardous to living organisms. The adsorption method is used in most wastewater plants for the removal of organic pollutants as it is cost-effective, has a high adsorption capacity, and good mechanical stabilities. In this study, a composite adsorbent was prepared by impregnating iron modified silica (FMS) onto polyurethane (PU) foam to produce an iron modified silica/polyurethane (FMS/PU) composite. The composite adsorbent was utilised in batch adsorption of the cationic dyes MB and MG. The effect of adsorption parameters such as the adsorbent load, pH, initial dye concentration, and contact time were discussed. Adsorption kinetics and isotherm were implemented to understand the adsorption mechanism for both dyes. It was found that the adsorption of MB and MG followed the pseudo-second order model. The Langmuir model showed a better fit than the Freundlich model for the adsorption of MB and MG, indicating that the adsorption occurred via the monolayer adsorption system. The maximum adsorption capacity of the FMS/PU obtained for MB was 31.7 mg/g, while for MG, it was 34.3 mg/g. The thermodynamic study revealed that the adsorption of MB and MG were exothermic and spontaneous at room temperature. In addition, the regeneration of FMS/PU was conducted to investigate the composite efficiency in adsorbing dyes for several cycles. The results showed that the FMS/PU composite could be regenerated up to four times when the regeneration efficiency dropped drastically to less than 20.0%. The impregnation of FMS onto PU foam also minimised the adsorbent loss into the environment.
Fulltext Preparation of Ethylene Glycol Dimethacrylate (EGDMA)-Based Terpolymer as Potential Sorbents for Pharmaceuticals Adsorption

Shaipulizan NS, Md Jamil SNA, Kamaruzaman S, Subri NNS, Adeyi AA, Abdullah AH, et al.

Polymers (Basel), 2020 Feb 12;12(2).
PMID: 32059354 DOI: 10.3390/polym12020423

Ethylene glycol dimethacrylate (EGDMA) is used as a crosslinker in poly(acrylonitrile (AN)-co-vinylbenzyl chloride (VBC)) to investigate the effect of long-chain crosslinker to the porosity of the terpolymer system. Poly(AN-co-EGDMA-co-VBC) is synthesized by using precipitation polymerization method and further hypercrosslinked by Friedel-Crafts reaction. FT-IR spectra of poly(AN-co-EGDMA-co-VBC) show that the absorption bands at ~1290 cm-1 that are assigned to the C-Cl vibrations are almost disappeared in hypercrosslinked (HXL) poly(AN-co-EGDMA-co-VBC) polymers, confirming that the hypercrosslinking reaction is successful. SEM images show that the morphologies of the polymers are retained through the hypercrosslinking reactions. Brunauer-Emmett-Teller (BET) analysis shows that hypercrosslinked polymers had a specific surface area up to 59 m2·g-1. The preliminary performance of the terpolymer adsorbent to capture polar analyte is evaluated by adsorbing salicylic acid and mefenamic acid from aqueous solution in a batch system. The maximum adsorption capacity of salicylic acid and mefenamic acid were up to 416.7 mg·g-1 and 625 mg·g-1, respectively, and the adsorption kinetic data obeyed pseudo-second-order rate equation.
Fulltext Recombinant Human erythropoietin reduces viability of MCF-7 breast cancer cells from 3D culture without caspase activation

ShujaaEdin HY, Al-Haj NA, Rasedee A, Alitheen NB, Kadir AA, How CW, et al.

Saudi J Biol Sci, 2021 Apr;28(4):2549-2557.
PMID: 33935571 DOI: 10.1016/j.sjbs.2021.01.059

Recombinant human erythropoietin (rHuEPO) is the erythropoiesis-stimulating hormone that is being used concurrently with chemotherapeutic drugs in the treatment of anemia of cancer. The effect of rHuEPO on cancer cells in 3-dimensional (3D) cultures is not known. The objective of the study was to determine the effect of rHuEPO on the viability of MCF-7 breast cancer cells from 2-dimensional (2D) and 3D cell cultures. The monolayer MCF-7 cells from 2D culture and MCF-7 cell from 3D culture generated by ultra-low adhesive microplate technique, were treated with 0, 0.1, 10, 100 or 200 IU/mL rHuEPO for 24, 48 or 72 h. The effects of rHuEPO on MCF-7 cell viability and proliferation were determined using the (4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay (MTT), neutral red retention time (NRRT), trypan blue exclusion assay (TBE), DNA fragmentation, acridine orange/propidium iodide staining (AO/PI) assays. The MCF-7 cells for 3D culture were also subjected to caspase assays and cell cycle analysis using flow cytometry. rHuEPO appeared to have greater effect at lowering the viability of MCF-7 cells from 3D than 2D cultures. rHuEPO significantly (p
Fulltext Semi-empirical study of ortho-cresol photo degradation in manganese-doped zinc oxide nanoparticles suspensions

Abdollahi Y, Zakaria A, Abdullah AH, Fard Masoumi HR, Jahangirian H, Shameli K, et al.

Chem Cent J, 2012 Aug 21;6(1):88.
PMID: 22909072 DOI: 10.1186/1752-153X-6-88

The optimization processes of photo degradation are complicated and expensive when it is performed with traditional methods such as one variable at a time. In this research, the condition of ortho-cresol (o-cresol) photo degradation was optimized by using a semi empirical method. First of all, the experiments were designed with four effective factors including irradiation time, pH, photo catalyst's amount, o-cresol concentration and photo degradation % as response by response surface methodology (RSM). The RSM used central composite design (CCD) method consists of 30 runs to obtain the actual responses. The actual responses were fitted with the second order algebraic polynomial equation to select a model (suggested model). The suggested model was validated by a few numbers of excellent statistical evidences in analysis of variance (ANOVA). The used evidences include high F-value (143.12), very low P-value (<0.0001), non-significant lack of fit, the determination coefficient (R2 = 0.99) and the adequate precision (47.067). To visualize the optimum, the validated model simulated the condition of variables and response (photo degradation %) be using a few number of three dimensional plots (3D). To confirm the model, the optimums were performed in laboratory. The results of performed experiments were quite close to the predicted values. In conclusion, the study indicated that the model is successful to simulate the optimum condition of o-cresol photo degradation under visible-light irradiation by manganese doped ZnO nanoparticles.
Hospital waiting time: the forgotten premise of healthcare service delivery?

Pillay DI, Ghazali RJ, Manaf NH, Abdullah AH, Bakar AA, Salikin F, et al.

Int J Health Care Qual Assur, 2011;24(7):506-22.
PMID: 22204085

This is a national study which aims to determine the average waiting time in Malaysian public hospitals and to gauge the level of patient satisfaction with the waiting time. It also aims to identify factors perceived by healthcare providers which contribute to the waiting time problem.
Fulltext A biomimetic sensor for the classification of honeys of different floral origin and the detection of adulteration

Zakaria A, Shakaff AY, Masnan MJ, Ahmad MN, Adom AH, Jaafar MN, et al.

Sensors (Basel), 2011;11(8):7799-822.
PMID: 22164046 DOI: 10.3390/s110807799

The major compounds in honey are carbohydrates such as monosaccharides and disaccharides. The same compounds are found in cane-sugar concentrates. Unfortunately when sugar concentrate is added to honey, laboratory assessments are found to be ineffective in detecting this adulteration. Unlike tracing heavy metals in honey, sugar adulterated honey is much trickier and harder to detect, and traditionally it has been very challenging to come up with a suitable method to prove the presence of adulterants in honey products. This paper proposes a combination of array sensing and multi-modality sensor fusion that can effectively discriminate the samples not only based on the compounds present in the sample but also mimic the way humans perceive flavours and aromas. Conversely, analytical instruments are based on chemical separations which may alter the properties of the volatiles or flavours of a particular honey. The present work is focused on classifying 18 samples of different honeys, sugar syrups and adulterated samples using data fusion of electronic nose (e-nose) and electronic tongue (e-tongue) measurements. Each group of samples was evaluated separately by the e-nose and e-tongue. Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) were able to separately discriminate monofloral honey from sugar syrup, and polyfloral honey from sugar and adulterated samples using the e-nose and e-tongue. The e-nose was observed to give better separation compared to e-tongue assessment, particularly when LDA was applied. However, when all samples were combined in one classification analysis, neither PCA nor LDA were able to discriminate between honeys of different floral origins, sugar syrup and adulterated samples. By applying a sensor fusion technique, the classification for the 18 different samples was improved. Significant improvement was observed using PCA, while LDA not only improved the discrimination but also gave better classification. An improvement in performance was also observed using a Probabilistic Neural Network classifier when the e-nose and e-tongue data were fused.
High incidence of Plasmodium knowlesi malaria compared to other human malaria species in several hospitals in Malaysia

Lai MY, Rafieqin N, Lee PYL, Amir Rawa MS, Dzul S, Yahaya N, et al.

Trop Biomed, 2021 Sep 01;38(3):248-253.
PMID: 34362867 DOI: 10.47665/tb.38.3.065

Through the regional control programme, Malaysia has been successfully reducing the incidence of Plasmodium falciparum and Plasmodium vivax infections. However, the incidence of zoonotic malaria Plasmodium knowlesi infection is increasing and now has been the major cause of malaria in Malaysia especially Malaysian Borneo. The emergence of knowlesi infection has threatened the malaria elimination programme which the government aims to reduce the overall malaria infections by 2020. Unlike other benign human Plasmodium spp., P. knowlesi can cause fatal infections. The aim of this study was to determine the incidence and distribution of five human malaria parasites including P. knowlesi in Peninsular Malaysia and Malaysian Borneo. A total of 112 blood samples were collected from seven states and district hospitals in Peninsular Malaysia and Malaysian Borneo from year 2015 to 2016. The samples were examined by microscopy and further confirmed by nested PCR assay targeting 18S rRNA gene of Plasmodium spp. Following the nested PCR assays, a total of 54 (48.2%) samples were positive for P. knowlesi infections, 12 (10.7%) cases were positive for P. vivax infections, followed by 7 (6.3%) cases of P. falciparum and 4 (3.5%) cases of P. malariae. There were 3 cases (2.7%) of mixed infections (P. knowlesi/P. vivax). However, no cases were identified as P. ovale. A total of 32 (28.6%) cases were found as negative infections. LoopMediated Isothermal Amplification Assay (LAMP) was performed to confirm inconclusive results produced by microscopy and nested PCR. P. knowlesi showed the highest prevalence in Sarawak (n= 30), Sabah (n=13), Pulau Pinang (n=5) and Pahang (n=6). PCR and LAMP was not able to detect a large number of microscopy positive samples due to DNA degradation during storage and shipping. Among all the states involved in this study, the highest prevalence of P. knowlesi infection was found in Sabah and Sarawak.
Fulltext Safety and Effectiveness of Bivalirudin in Patients Undergoing Percutaneous Coronary Intervention: A Systematic Review and Meta-Analysis

Ahmad Hamdi AH, Dali AF, Mat Nuri TH, Saleh MS, Ajmi NN, Neoh CF, et al.

Front Pharmacol, 2017;8:410.
PMID: 28744215 DOI: 10.3389/fphar.2017.00410

Recent clinical trials have shown that while bivalirudin exhibits similar efficacy with heparin, it offers several advantages over heparin, such as a better safety profile. We aimed to evaluate the efficacy and safety of bivalirudin use during Percutaneous Coronary Intervention (PCI) in the treatment of angina and acute coronary syndrome (ACS). We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, PubMed, EMBASE, and Science Direct from January 1980 to January 2016. Randomized controlled trials (RCTs) comparing bivalirudin to heparin during the course of PCI in patients with angina or ACS were included. Outcome measures included all-cause mortality, myocardial infarction, revascularisation, stent thrombosis, stroke, and major bleeding. The selection, quality assessment, and data extraction of the included trials were done independently by four authors, and disagreements were resolved by consensus. Pooled relative risk (RR) estimates and 95% confidence intervals (CIs) were calculated. A total of 12 RCTs involving 44,088 subjects were included. Bivalirudin appeared to be non-superior compared to heparin in reducing all-cause mortality, myocardial infarction, revascularisation, and stroke. Bivalirudin appeared to be related to a higher risk of stent thrombosis when compared to heparin plus provisional use of a glycoprotein IIb/IIIa inhibitor (GPI) at day 30 (RR 1.94 [1.16, 3.24] p < 0.01). Overall, bivalirudin-based regimens present a lesser risk of major bleeding (RR 0.56 [0.44-0.71] p < 0.001), and Thrombolysis In Myocardial Infarction (TIMI) major bleeding (RR 0.56 [0.43-0.73]) compared with heparin-based regimens either with provisional or routine use of a GPI. However, the magnitude of TIMI major bleeding effect varied greatly (p < 0.001), depending on whether a GPI was provisionally used (RR 0.42 [0.34-0.52] p < 0.001) or routinely used (RR 0.60 [0.43 -0.83] p < 0.001), in the heparin arm. This meta-analysis demonstrated that bivalirudin is associated with a lower risk of major bleeding, but a higher risk of stent thrombosis compared to heparin.
Fulltext Effect of fetal bovine serum on erythropoietin receptor expression and viability of breast cancer cells

Teo GY, Rasedee A, Al-Haj NA, Beh CY, How CW, Rahman HS, et al.

Saudi J Biol Sci, 2020 Feb;27(2):653-658.
PMID: 32210684 DOI: 10.1016/j.sjbs.2019.11.032

Erythropoietin receptors (EPORs) are present not only in erythrocyte precursors but also in non-hematopoietic cells including cancer cells. In this study, we determined the effect of fetal bovine serum (FBS) in culture medium on the EPOR expression and viability of the estrogen receptor (ER)-positive MCF-7 and ER-negative MDA-MB-231 breast cancer cells. Using flow cytometry, we showed that the inclusion of 10% FBS in the medium increased the EPOR expressions and viabilities of MDA-MB-231 and MCF-7 cells. The MDA-MB-231 showed greater EPOR expression than MCF-7 cells, suggesting that the presence of ERs on cells is associated with poor expression of EPOR. Culture medium containing 10% FBS also caused increased number of breast cancer cells entering the synthesis phase of the cell cycle. The study also showed that rHuEPO treatment did not affect viability of breast cancer cells. In conclusion, it was shown that the inclusion of FBS in culture medium increased expression of EPOR in breast cancer cells and rHuEPO treatment had no effect on the proliferation of these cancer cells.
Poor sleep quality in children with atopic dermatitis and its effects on behavior: A multicenter cross-sectional study from a low-middle-income country

Abdullah AH, Nathan AM, Jayanath S, Kwan Z, Azanan MS, Hng SY, et al.

Pediatr Int, 2023 Jan;65(1):e15473.
PMID: 36645391 DOI: 10.1111/ped.15473

BACKGROUND: Sleep disturbance in children with atopic dermatitis (AD) frequently goes unnoticed and can be associated with behavioral challenges. The aims of this study were to determine (a) the prevalence and factors associated with sleep disturbance and behavioral problems and (b) the correlation between sleep disturbance and behavioral problems in children with AD.
METHODS: This cross-sectional study involved children aged 4-12 years old with moderate to severe AD. Age and sex-matched healthy children were recruited as the comparison group. The Children's Sleep Habits Questionnaire (CSHQ) and the Strengths and Difficulties Questionnaire (SDQ) were used to assess sleep disturbance and behavioral problems, respectively. Higher scores in both questionnaires signify more disturbance.
RESULTS: Seventy patients and 141 controls were recruited. Median (interquartile range) age of patients was 5 (4,8) years. Patients had later sleep time (p
Fulltext Knowledge and Perception of Facial Candling for Allergic Rhinitis among University Staff and Students

Hamdan NKA, Lean QY, Neoh CF, Abdullah AH, Lim SM, Ramasamy K, et al.

Evid Based Complement Alternat Med, 2020;2020:5713134.
PMID: 32831870 DOI: 10.1155/2020/5713134

Introduction: Facial candling is a traditional method used for relieving symptoms of allergic rhinitis (AR). This study aims to investigate the knowledge and perception of facial candling in a sample of staff and students in a public university in Malaysia.
Methods: An online questionnaire survey method was used. Based on sample size calculation, a total of 1,508 UiTM staff and students from ten selected campuses of Universiti Teknologi MARA (UiTM) were invited to participate in this survey. An up-to-date e-mail list of staff in the selected campuses was used as the sampling frame for the study, whereas the students were recruited from the official university student Facebook portal.
Results: A total of 788 respondents participated in this survey, 72.2% of them knew about facial candling, though only 35.4% had tried the treatment. Approximately one-fifth of respondents agreed that facial candling might treat AR. It was found that a higher number of users than nonusers agreed that facial candling was a traditional medicine (78.9% vs 55.0%); could be used on the face and ears (83.5% vs 45.4%); and could be self-administered at home (83.5 vs 45.4%). Interestingly, more than half of them were uncertain about its long-term effects and adverse reactions.
Conclusion: This study confirms the facial candling use among patients with AR although the percentage is low. The patients and general public need to be better informed about the use of facial candling in AR and its associated risks.
Fulltext Non-rebreather mask and low-flow nasal cannula vs high-flow nasal cannula in severe COVID-19 pneumonia in the emergency department

Mohd Kamil MK, Yuen Yoong KP, Noor Azhar AM, Bustam A, Abdullah AH, Md Yusuf MH, et al.

Am J Emerg Med, 2023 Jan;63:86-93.
PMID: 36327755 DOI: 10.1016/j.ajem.2022.10.029

BACKGROUND: To assess the effectiveness of non-rebreather mask combined with low-flow nasal cannula (NRB + NC) compared to high-flow nasal cannula (HFNC) in improving oxygenation in patients with COVID-19-related hypoxemic respiratory failure (HRF).
METHODS: This retrospective study was conducted in emergency departments of two tertiary hospitals from June 1 to August 31, 2021. Consecutive patients aged >18 years admitted for COVID-19-related HRF (World Health Organization criteria: confirmed COVID-19 pneumonia with respiratory rate > 30 breaths/min, severe respiratory distress, or peripheral oxygen saturation < 90% on room air) requiring NRB + NC or HFNC were screened for enrollment. Primary outcome was improvement of partial pressure arterial oxygen (PaO2) at two hours. Secondary outcomes were intubation rate, ventilator-free days, hospital length of stay, and 28-day mortality. Data were analyzed using linear regression with inverse probability of treatment weighting (IPTW) based on propensity score.
RESULTS: Among the 110 patients recruited, 52 (47.3%) were treated with NRB + NC, and 58 (52.7%) with HFNC. There were significant improvements in patients' PaO2, PaO2/FIO2 ratio, and respiratory rate two hours after the initiation of NRB + NC and HFNC. Comparing the two groups, after IPTW adjustment, there were no statistically significant differences in PaO2 improvement (adjusted mean ratio [MR] 2.81; 95% CI -5.82 to 11.43; p = .524), intubation rate (adjusted OR 1.76; 95% CI 0.44 to 6.92; p = .423), ventilator-free days (adjusted MR 0.00; 95% CI -8.84 to 8.85; p = .999), hospital length of stay (adjusted MR 3.04; 95% CI -2.62 to 8.69; p = .293), and 28-day mortality (adjusted OR 0.68; 95% CI 0.15 to 2.98; p = .608).
CONCLUSION: HFNC may be beneficial in COVID-19 HRF. NRB + NC is a viable alternative, especially in resource-limited settings, given similar improvement in oxygenation at two hours, and no significant differences in long-term outcomes. The effectiveness of NRB + NC needs to be investigated by a powered randomized controlled trial.
Fulltext Enhancing sand screen performance with integrated slurry testing and CFD-DEM modelling

Su NC, Izwani Jusof SA, Zainal AZ, Jian YY, Xian CK, Laziz AM, et al.

Heliyon, 2025 Jan 15;11(1):e40877.
PMID: 39801980 DOI: 10.1016/j.heliyon.2024.e40877

Understanding the behavior of sand screens is crucial for optimizing sand control strategies and preventing wellbore failure, which can significantly impact reservoir management and production efficiency. This paper presents a comprehensive experimental and numerical modeling study on sand screen performance, aimed at providing insights prior to real-field applications. The study evaluated a 200-μm wire-wrapped screen (WWS) using slurry tests to determine the amount of sand retained, sand produced and retained permeability to assess screen efficiency. The particle size distribution (PSD) of sand samples was crucial for selecting the appropriate screen size, with results showing that highly uniform and well-sorted sand exhibited higher sand retention and lower sand production due to reduced fines content and maximized void spaces, enhancing fluid flow while mitigating sand production. A coupled Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) simulation platform was employed to model particle-fluid interactions, using an optimal mesh size of 0.005 m. The simulation results showed a high degree of correlation with experimental data, with 93.1 % similarity in sand retention and 63.22 % in sand production. These findings underscore the potential of CFD-DEM simulations in accurately replicating complex sand control processes and optimizing screen performance for enhanced wellbore stability and production efficiency.
From tap to table: An assessment of drinking water quality in Perak, Malaysia

Ibrahim TNBT, Feisal NAS, Azmi NM, Nazli SN, Salehuddin ASM, Nasir NICM, et al.

Med J Malaysia, 2024 Mar;79(Suppl 1):14-22.
PMID: 38555880

INTRODUCTION: A study on the quality of drinking water was conducted at Air Kuning Treatment Plant In Perak, Malaysia, based on a sanitary survey in 14 sampling points stations from the intake area to the auxiliary points. This was to ensure the continuous supply of clean and safe drinking water to the consumers for public health protection. The objective was to examine the physical, microbiological, and chemical parameters of the water, classification at each site based on National Drinking Water Standards (NDWQS) and to understand the spatial variation using environmetric technique; principal component analysis (PCA).
MATERIALS AND METHODS: Water samples were subjected to in situ and laboratory water quality analyses and focused on pH, turbidity, chlorine, Escherichia coli, total coliform, total hardness, iron (Fe), aluminium (Al), zinc (Zn), magnesium (Mg) and sodium (Na). All procedures followed the American Public Health Association (APHA) testing procedures.
RESULTS: Based on the results obtained, the values of each parameter were found to be within the safe limits set by the NDWQS except for total coliform and iron (Fe). PCA has indicated that turbidity, total coliform, E. coli, Na, and Al were the major factors that contributed to the drinking water contamination in river water intake.
CONCLUSION: Overall, the water from all sampling point stations after undergoing water treatment process was found to be safe as drinking water. It is important to evaluate the drinking water quality of the treatment plant to ensure that consumers have access to safe and clean drinking water as well as community awareness on drinking water quality is essential to promote public health and environmental protection.

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