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Fulltext Synthesis of a nano-silver metal ink for use in thick conductive film fabrication applied on a semiconductor package

Yung LC, Fei CC, Mandeep J, Binti Abdullah H, Wee LK

PLoS One, 2014;9(5):e97484.
PMID: 24830317 DOI: 10.1371/journal.pone.0097484

The success of printing technology in the electronics industry primarily depends on the availability of metal printing ink. Various types of commercially available metal ink are widely used in different industries such as the solar cell, radio frequency identification (RFID) and light emitting diode (LED) industries, with limited usage in semiconductor packaging. The use of printed ink in semiconductor IC packaging is limited by several factors such as poor electrical performance and mechanical strength. Poor adhesion of the printed metal track to the epoxy molding compound is another critical factor that has caused a decline in interest in the application of printing technology to the semiconductor industry. In this study, two different groups of adhesion promoters, based on metal and polymer groups, were used to promote adhesion between the printed ink and the epoxy molding substrate. The experimental data show that silver ink with a metal oxide adhesion promoter adheres better than silver ink with a polymer adhesion promoter. This result can be explained by the hydroxyl bonding between the metal oxide promoter and the silane grouping agent on the epoxy substrate, which contributes a greater adhesion strength compared to the polymer adhesion promoter. Hypotheses of the physical and chemical functions of both adhesion promoters are described in detail.
A new mechanism of thermal sensitivity for rapid drug release and low systemic toxicity in hyperthermia and thermal ablation temperature ranges

Dabbagh A, Abdullah BJ, Abu Kasim NH, Abdullah H, Hamdi M

Int J Hyperthermia, 2015 Jun;31(4):375-85.
PMID: 25716769 DOI: 10.3109/02656736.2015.1006268

The aim of this paper was to introduce a new mechanism of thermal sensitivity in nanocarriers that results in a relatively low drug release at physiological temperature and rapid release of the encapsulated drug at hyperthermia and thermal ablation temperature range (40-60 °C).
Triggering Mechanisms of Thermosensitive Nanoparticles Under Hyperthermia Condition

Dabbagh A, Abdullah BJ, Abdullah H, Hamdi M, Kasim NH

J Pharm Sci, 2015 Aug;104(8):2414-28.
PMID: 26073304 DOI: 10.1002/jps.24536

Nanoparticle-based hyperthermia is an effective therapeutic approach that allows time- and site-specific treatment with minimized off-site effects. The recent advances in materials science have led to design a diversity of thermosensitive nanostructures that exhibit different mechanisms of thermal response to the external stimuli. This article aims to provide an extensive review of the various triggering mechanisms in the nanostructures used as adjuvants to hyperthermia modalities. Understanding the differences between various mechanisms of thermal response in these nanostructures could help researchers in the selection of appropriate materials for each experimental and clinical condition as well as to address the current shortcomings of these mechanisms with improved material design.
Low-melting-point polymeric nanoshells for thermal-triggered drug release under hyperthermia condition

Dabbagh A, Mahmoodian R, Abdullah BJ, Abdullah H, Hamdi M, Abu Kasim NH

Int J Hyperthermia, 2015;31(8):920-9.
PMID: 26670340 DOI: 10.3109/02656736.2015.1094147

The aim of this paper was to synthesise core-shell nanostructures comprised of mesoporous silica core and a low melting-point polyethylene glycol (PEG) nanoshell with a sharp gel-liquid phase transition for rapid drug release at hyperthermia temperature range.
Fulltext Anti-Candida activity of Quercus infectoria gall extracts against Candida species

Baharuddin NS, Abdullah H, Abdul Wahab WN

J Pharm Bioallied Sci, 2015 Jan-Mar;7(1):15-20.
PMID: 25709331 DOI: 10.4103/0975-7406.148742

Galls of Quercus infectoria have been traditionally used to treat common ailments, including yeast infections caused by Candida species.
Fulltext Structural, Morphological, and Electron Transport Studies of Annealing Dependent In2O3 Dye-Sensitized Solar Cell

Mahalingam S, Abdullah H, Shaari S, Muchtar A, Asshari I

ScientificWorldJournal, 2015;2015:403848.
PMID: 26146652 DOI: 10.1155/2015/403848

Indium oxide (In2O3) thin films annealed at various annealing temperatures were prepared by using spin-coating method for dye-sensitized solar cells (DSSCs). The objective of this research is to enhance the photovoltaic conversion efficiency in In2O3 thin films by finding the optimum annealing temperature and also to study the reason for high and low performance in the annealed In2O3 thin films. The structural and morphological characteristics of In2O3 thin films were studied via XRD patterns, atomic force microscopy (AFM), field-emission scanning electron microscopy (FESEM), EDX sampling, and transmission electron microscopy (TEM). The annealing treatment modified the nanostructures of the In2O3 thin films viewed through FESEM images. The In2O3-450 °C-based DSSC exhibited better photovoltaic performance than the other annealed thin films of 1.54%. The electron properties were studied by electrochemical impedance spectroscopy (EIS) unit. The In2O3-450 °C thin films provide larger diffusion rate, low recombination effect, and longer electron lifetime, thus enhancing the performance of DSSC.
Fulltext Thermal Annealing Effect on Structural, Morphological, and Sensor Performance of PANI-Ag-Fe Based Electrochemical E. coli Sensor for Environmental Monitoring

Mohammad Naim N, Abdullah H, Umar AA, Abdul Hamid A, Shaari S

ScientificWorldJournal, 2015;2015:696521.
PMID: 26078996 DOI: 10.1155/2015/696521

PANI-Ag-Fe nanocomposite thin films based electrochemical E. coli sensor was developed with thermal annealing. PANI-Ag-Fe nanocomposite thin films were prepared by oxidative polymerization of aniline and the reduction process of Ag-Fe bimetallic compound with the presence of nitric acid and PVA. The films were deposited on glass substrate using spin-coating technique before they were annealed at 300 °C. The films were characterized using XRD, UV-Vis spectroscopy, and FESEM to study the structural and morphological properties. The electrochemical sensor performance was conducted using I-V measurement electrochemical impedance spectroscopy (EIS). The sensitivity upon the presence of E. coli was measured in clean water and E. coli solution. From XRD analysis, the crystallite sizes were found to become larger for the samples after annealing. UV-Vis absorption bands for samples before and after annealing show maximum absorbance peaks at around 422 nm-424 nm and 426 nm-464 nm, respectively. FESEM images show the diameter size for nanospherical Ag-Fe alloy particles increases after annealing. The sensor performance of PANI-Ag-Fe nanocomposite thin films upon E. coli cells in liquid medium indicates the sensitivity increases after annealing.
Fulltext Quercus infectoria Gall Extract Enhanced the Proliferation and Activity of Human Fetal Osteoblast Cell Line (hFOB 1.19)

Hapidin H, Rozelan D, Abdullah H, Wan Hanaffi WN, Soelaiman IN

Malays J Med Sci, 2015 Jan-Feb;22(1):12-22.
PMID: 25892946 MyJurnal

The present study investigated the effects of Quercus infectoria (QI) gall extract on the proliferation, alkaline phosphatase (ALP), osteocalcin, and the morphology of a human fetal osteoblast cell line (hFOB 1.19).
The impact of CO2 emissions on economic growth: evidence from selected higher CO2 emissions economies

Azam M, Khan AQ, Bin Abdullah H, Qureshi ME

Environ Sci Pollut Res Int, 2016 Apr;23(7):6376-89.
PMID: 26620862 DOI: 10.1007/s11356-015-5817-4

The main purpose of this work is to analyze the impact of environmental degradation proxied by CO2 emissions per capita along with some other explanatory variables namely energy use, trade, and human capital on economic growth in selected higher CO2 emissions economies namely China, the USA, India, and Japan. For empirical analysis, annual data over the period spanning between 1971 and 2013 are used. After using relevant and suitable tests for checking data properties, the panel fully modified ordinary least squares (FMOLS) method is employed as an analytical technique for parameter estimation. The panel group FMOLS results reveal that almost all variables are statistically significant, whereby test rejects the null hypotheses of non cointegration, demonstrating that all variables play an important role in affecting the economic growth role across countries. Where two regressors namely CO2 emissions and energy use show significantly negative impacts on economic growth, for trade and human capital, they tend to show the significantly positive impact on economic growth. However, for the individual analysis across countries, the panel estimate suggests that CO2 emissions have a significant positive relationship with economic growth for China, Japan, and the USA, while it is found significantly negative in case of India. The empirical findings of the study suggest that appropriate and prudent policies are required in order to control pollution emerging from areas other than liquefied fuel consumption. The ultimate impact of shrinking pollution will help in supporting sustainable economic growth and maturation as well as largely improve society welfare.
Pathways to Youth Empowerment and Community Connectedness: A Study of Youth-Adult Partnership in Malaysian After-School, Co-Curricular Programs

Zeldin S, Krauss SE, Kim T, Collura J, Abdullah H

J Youth Adolesc, 2016 08;45(8):1638-51.
PMID: 26092232 DOI: 10.1007/s10964-015-0320-2

After-school programs are prevalent across the world, but there is a paucity of research that examines quality within the "black box" of programs at the point of service. Grounded in current theory, this research examined hypothesized pathways between the experience of youth-adult partnership (youth voice in decision-making; supportive adult relationships), the mediators of program safety and engagement, and the developmental outcomes of youth empowerment (leadership competence, policy control) and community connectedness (community connections, school attachment). Surveys were administered to 207 ethnically diverse (47.3 % female; 63.3 % Malay) youth, age 15-16, attending after-school co-curricular programs in Kuala Lumpur, Malaysia. Results showed that youth voice in program decision-making predicted both indicators of youth empowerment. Neither youth voice nor supportive adult relationships was directly associated with community connectedness, however. Program engagement mediated the associations between youth-adult partnership and empowerment. In contrast, program safety mediated the associations between youth-adult partnership and community connectedness. The findings indicate that the two core components of youth-adult partnership-youth voice and supportive adult relationships-may operate through different, yet complementary, pathways of program quality to predict developmental outcomes. Implications for future research are highlighted. For reasons of youth development and youth rights, the immediate challenge is to create opportunities for youth to speak on issues of program concern and to elevate those adults who are able and willing to help youth exercise their voice.
Fulltext Nicotine-prevented learning and memory impairment in REM sleep-deprived rat is modulated by DREAM protein in the hippocampus

Abd Rashid N, Hapidin H, Abdullah H, Ismail Z, Long I

Brain Behav, 2017 06;7(6):e00704.
PMID: 28638710 DOI: 10.1002/brb3.704

INTRODUCTION: REM sleep deprivation is associated with impairment in learning and memory, and nicotine treatment has been shown to attenuate this effect. Recent studies have demonstrated the importance of DREAM protein in learning and memory processes. This study investigates the association of DREAM protein in REM sleep-deprived rats hippocampus upon nicotine treatment.
METHODS: Male Sprague Dawley rats were subjected to normal condition, REM sleep deprivation and control wide platform condition for 72 hr. During this procedure, saline or nicotine (1 mg/kg) was given subcutaneously twice a day. Then, Morris water maze (MWM) test was used to assess learning and memory performance of the rats. The rats were sacrificed and the brain was harvested for immunohistochemistry and Western blot analysis.
RESULTS: MWM test found that REM sleep deprivation significantly impaired learning and memory performance without defect in locomotor function associated with a significant increase in hippocampus DREAM protein expression in CA1, CA2, CA3, and DG regions and the mean relative level of DREAM protein compared to other experimental groups. Treatment with acute nicotine significantly prevented these effects and decreased expression of DREAM protein in all the hippocampus regions but only slightly reduce the mean relative level of DREAM protein.
CONCLUSION: This study suggests that changes in DREAM protein expression in CA1, CA2, CA3, and DG regions of rat's hippocampus and mean relative level of DREAM protein may involve in the mechanism of nicotine treatment-prevented REM sleep deprivation-induced learning and memory impairment in rats.
Fulltext Fetal MRI of thoraco-omphalopagus conjoined twins

Abdullah H, Abdul Wahab N, Abu Bakar K

BMJ Case Rep, 2017 Jun 13;2017.
PMID: 28611167 DOI: 10.1136/bcr-2017-219793
Undiagnosed acute phase endobronchial tuberculosis with progression to irreversible tracheobronchial stenosis

Abdullah H, Quek CZ

BMJ Case Rep, 2017 Aug 07;2017.
PMID: 28784877 DOI: 10.1136/bcr-2017-219877
Multimodality cardiac imaging of submitral left ventricular aneurysm with concurrent descending aorta mycotic aneurysm

Abdullah H, Jiyen K, Othman N

BMJ Case Rep, 2017 Sep 27;2017.
PMID: 28954754 DOI: 10.1136/bcr-2017-221466

We present a case of a 20-year-old Malay man with underlying tuberculous (TB) lymphadenitis who presented with shortness of breath and found to have submitral left ventricular aneurysm (SLVA). SLVA is well recognised but rare. Incidence of SLVA in Malay has never been documented. This is the first reported case of SLVA in Malays with concomitant thoracic aorta mycotic aneurysm. TB has been reported to be associated with SLVA. Treatment is either surgical or conservative. Imaging is required for diagnosis and preoperative assessment. Multimodality imaging include echocardiography (ECHO), cardiac CTangiography and the robust multiparametric cardiac MR (CMR). ECHO is the first line imaging and useful for initial detection of the aneurysm. CMR including the late gadolinium enhancement allows excellent visualisation of the LV aneurysm, tissue characterisation, cardiac function and detection of associated pathology as shown in this case.
Fulltext The use of febuxostat for gout in Hospital Tengku Ampuan Afzan (HTAA) Kuantan. [Abstract]

Abdullah H

International Medical Journal Malaysia, 2017;16(11):50.
MyJurnal

Introduction: Febuxostat is a non-purine-selective oral xanthine oxidase inhibitor drug, and is an alternative to Allopurinol to lower serum uric acid in gout patients. It is probably more effective than Allopurinol, however, its use is limited because of its cost and availability. Allopurinol has been the mainstay treatment for gout for about 50 years. However, its use has been associated with allergic reactions especially in patients with renal impairment.The objective of this study was to describe HTAA Rheumatology Unit experiences with Febuxostat in the management of gout.
Materials and method: Case records belonging to 6 patients who had been started on Febuxostat between January 2012 and January 2017 were analysed.
Results: The majority of patients on Febuxostat were males (83.3%) as well as Malays (83.3%). About 66.7% of patients had already developed mild to moderate chronic kidney disease (GFR between 30-89 mL/min) due to multifactorial causes by the time they were started on Febuxostat. Also 33% of patients had mild liver impairment (ALT & AST < 1.5 ULN) due to fatty liver prior to Febuxostat. All patients had been started on Febuxostat due to allergic reactions to Allopurinol. All patients were on Febuxostat 40 mg once a day. Following Febuxostat, a significant decrease in the uric acid levels much closer to the target level i.e. less than 360 µmol/L were achieved in all patients. Only 1 patient (16.7%) developed a side effect i.e. ALT > 1.5 ULN while the rest tolerated the drug very well.
Conclusion: Although the number of patients analysed was small, Febuxostat was shown to be very effective and safe for use in patients with gout even with concomitant mild to moderate renal impairment. Serum uric acid levels reduced significantly while on the lowest dose of 40 mg once a day.
Fulltext Clinical Outcomes and Predictors of Satisfaction in Patients with Improved Lithium Disilicate All-Ceramic Crowns

Samer MS, Faraz Q, Al-Dubai SAR, Vohra F, Abdullah H, Taiyeb-Ali TB, et al.

Med Princ Pract, 2017;26(5):470-479.
PMID: 28965115 DOI: 10.1159/000481864

OBJECTIVES: The aim of this study was to determine the clinical outcomes and predictors of satisfaction in patients with lithium disilicate (LD) ceramic crowns.
SUBJECTS AND METHODS: Clinical outcomes were assessed in 47 patients with 88 LD crowns using modified United States Public Health Service (USPHS) evaluation criteria and survival rates. The questionnaire for predictors included 3 aspects: (a) sociodemographic characteristics, (b) oral health habits (tooth brushing frequency, flossing frequency, and dental visits), and (c) satisfaction of the restorations (aesthetics, function, fit, cleansability, and chewing ability of the crowns, and overall satisfaction). Frequency distributions were computed using univariate and multivariate analysis. The Student t test and analysis of variance (ANOVA) were used to compare means across variables. Correlation analysis was done to assess the association between continuous variables.
RESULTS: The age of crowns was 34.7 ± 9.7 months. The survival rate was 96.6% at 35.9 ± 9.2 months. There was a significant association between successful crown function and oral hygiene measures: tooth brushing (p˂ 0.001), dental visits (p = 0.006), and flossing (p = 0.009). A strong negative correlation was observed between aesthetic satisfaction (r = -0.717, p˂ 0.001) and chewing ability (r = -0.639, p˂ 0.001) with crown age. The linear regression model was significant for all predictors (p < 0.05) except overall satisfaction (p > 0.05).
CONCLUSION: The LD crowns had long survival rates of 96.6% up to 35.9 ± 9.2 months and provided satisfactory clinical performance (low risk of failure). Oral hygiene habits such as brushing, flossing, and regular dental visits influenced patient satisfaction with LD crowns.
Clinical Outcomes of Lithium Disilicate Single Crowns after a Mean Duration of 3 Years - A Retrospective Study

Saleh Samer M, Ali TT, Abdullah H

Oral Health Prev Dent, 2018 7 22;16(3):249-257.
PMID: 30027164 DOI: 10.3290/j.ohpd.a40758

PURPOSE: To investigate the clinical performance and clinical survival rate of lithium disilicate-based core ceramic (IPS e.max Press) utilised in single crowns and to the accompanying periodontal health status.
MATERIALS AND METHODS: A total of 47 patients with 88 IPS e.max Press single crowns were examined at the Faculty of Dentistry, University of Malaya, using modified United States Public Health Service evaluation criteria (USPHS). These 88 crowned teeth included 19 vital and 69 nonvital teeth that were restored with different post and core materials. The periodontal status was compared using the plaque index (PI), gingival recession (GR), modified papillary bleeding index (MPBI) and probing pocket depth (PPD) between the crowned teeth and contralateral control (sound) teeth.
RESULTS: About 96.6% of the crowns exhibited satisfactory clinical performance. The mean survival rate at three years was 97.7%, and 100% at two years with a low incidence of fractures. There were no staitistically significant differences in the mean gingival recession (p = 0.182) and mean plaque scores (p = 0.102) between crowned and control teeth. The crowned teeth had higher mean MPBI (p = 0.000) and PPD (p = 0.051) compared to the contralateral sound teeth. Periodontal response in relation to subgingival crown margins, was statistically significantly lower regarding pocket depths (p = 0.01) and bleeding on probing (p = 0.00).
CONCLUSION: IPS e.max Press crowns exhibited satisfactory clinical performance with high survival rate. No dentinal sensitivity was recorded. Plaque retention and gingival recession were similar to contralateral control teeth. Poor periodontal health was related to the subgingival crown margins.
Novel docetaxel chitosan-coated PLGA/PCL nanoparticles with magnified cytotoxicity and bioavailability

Badran MM, Alomrani AH, Harisa GI, Ashour AE, Kumar A, Yassin AE

Biomed Pharmacother, 2018 Oct;106:1461-1468.
PMID: 30119220 DOI: 10.1016/j.biopha.2018.07.102

In the present study, docetaxel (DTX)-loaded poly(lactic-co-glycolic acid) (PLGA) and polycaprolactone (PCL) nanoparticles were successfully prepared and coated with chitosan (CS). The prepared nanoparticles (NPs) were evaluated for their particle size, zeta potential, particle morphology, drug entrapment efficiency (EE%), and in vitro drug release profile. The anticancer activity of DTX-loaded NPs was assessed in human HT29 colon cancer cell line utilizing MTT assay. The pharmacokinetics of DTX-loaded NPs was monitored in Wistar rats in comparison to DTX solution. The prepared NPs exhibited particle sizes in the range 177.1 ± 8.2-287.6 ± 14.3 nm. CS decorated NPs exhibited a significant increase in particle size and a switch of zeta potential from negative to positive. In addition, high EE% values were obtained for CS coated PCL NPs and PLGA NPs as 67.1 and 76.2%, respectively. Moreover, lowering the rate of DTX in vitro release was achieved within 48 h by using CS coated NPs. Furthermore, a tremendous increase in DTX cytotoxicity was observed by CS-decorated PLGA NPs compared to all other NPs including DTX-free-NPs and pure DTX. The in vivo study revealed significant enhancement in DTX bioavailability from CS-decorated PLGA NPs with more than 4-fold increase in AUC compared to DTX solution. In conclusion, CS-decorated PLGA NPs are a considerable DTX-delivery carrier with magnificent antitumor efficacy.
Fulltext RESPIRE: The National Institute for Health Research's (NIHR) Global Respiratory Health Unit

Sheikh A, Campbell H, Balharry D, Baqui AH, Bogaert D, Cresswell K, et al.

J Glob Health, 2018 Dec;8(2):020101.
PMID: 30603074 DOI: 10.7189/jogh.08.020101
Fulltext Effect of porosity on compressive strength of resin modified glass ionomer luting cements

Al-Kadhim, A.H.A., Abdullah H.

International Medical Journal Malaysia, 2018;17(2):33-40.
MyJurnal

Introduction: The purpose of this study was to decide on the relation between types of mixing and the porosity of diameter (1-100) µm and compressive strength of RMGIC. Methods: Fifteen specimens 6mm height and 4mm in diameter were prepared for each type of luting cement and were stored in distilled water at 37° C for 24 hours. The compressive strength was determined. The fractured surfaces of 10 randomly selected specimens of each cement type were analyzed using SEM at 250 times magnification, and five photomicrographs were taken at five random places. All the photomicrographs were analyzed using image analyzer software to determine the amount and size of porosity present. Results: There was no significant difference in compressive strength between different mixing methods, but it had a significant impact by increasing the percentage of porosity of diameter (1-100) µm in diameter of RMGIC. There was no linear relationship between compressive strength and porosity (1-100) µm in diameter for both types of luting cements (P>0.05). Conclusion: No significant differences in compressive strength were found using different mixing methods. The size and number of porosity in the specimens of encapsulated cements were greater than those of hand-mixed cements. The porosity (1-100) µm in diameter and the compressive strength bore no linear relationship to each other.

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