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Fulltext Optimisation of Simultaneous Saccharification and Fermentation (SSF) for Biobutanol Production Using Pretreated Oil Palm Empty Fruit Bunch

Md Razali NAA, Ibrahim MF, Kamal Bahrin E, Abd-Aziz S

Molecules, 2018 Aug 03;23(8).
PMID: 30081514 DOI: 10.3390/molecules23081944

This study was conducted in order to optimise simultaneous saccharification and fermentation (SSF) for biobutanol production from a pretreated oil palm empty fruit bunch (OPEFB) by Clostridium acetobutylicum ATCC 824. Temperature, initial pH, cellulase loading and substrate concentration were screened using one factor at a time (OFAT) and further statistically optimised by central composite design (CCD) using the response surface methodology (RSM) approach. Approximately 2.47 g/L of biobutanol concentration and 0.10 g/g of biobutanol yield were obtained after being screened through OFAT with 29.55% increment (1.42 fold). The optimised conditions for SSF after CCD were: temperature of 35 °C, initial pH of 5.5, cellulase loading of 15 FPU/g-substrate and substrate concentration of 5% (w/v). This optimisation study resulted in 55.95% increment (2.14 fold) of biobutanol concentration equivalent to 3.97 g/L and biobutanol yield of 0.16 g/g. The model and optimisation design obtained from this study are important for further improvement of biobutanol production, especially in consolidated bioprocessing technology.
Fulltext Microbiome analysis of Pacific white shrimp gut and rearing water from Malaysia and Vietnam: implications for aquaculture research and management

Md Zoqratt MZH, Eng WWH, Thai BT, Austin CM, Gan HM

PeerJ, 2018;6:e5826.
PMID: 30397546 DOI: 10.7717/peerj.5826

Aquaculture production of the Pacific white shrimp is the largest in the world for crustacean species. Crucial to the sustainable global production of this important seafood species is a fundamental understanding of the shrimp gut microbiota and its relationship to the microbial ecology of shrimp pond. This is especially true, given the recently recognized role of beneficial microbes in promoting shrimp nutrient intake and in conferring resistance against pathogens. Unfortunately, aquaculture-related microbiome studies are scarce in Southeast Asia countries despite the severe impact of early mortality syndrome outbreaks on shrimp production in the region. In this study, we employed the 16S rRNA amplicon (V3-V4 region) sequencing and amplicon sequence variants (ASV) method to investigate the microbial diversity of shrimp guts and pond water samples collected from aquaculture farms located in Malaysia and Vietnam. Substantial differences in the pond microbiota were observed between countries with the presence and absence of several taxa extending to the family level. Microbial diversity of the shrimp gut was found to be generally lower than that of the pond environments with a few ubiquitous genera representing a majority of the shrimp gut microbial diversity such as Vibrio and Photobacterium, indicating host-specific selection of microbial species. Given the high sequence conservation of the 16S rRNA gene, we assessed its veracity at distinguishing Vibrio species based on nucleotide alignment against type strain reference sequences and demonstrated the utility of ASV approach in uncovering a wider diversity of Vibrio species compared to the conventional OTU clustering approach.
Fulltext Synthesis and Optimization of Chitosan Nanoparticles Loaded with L-Ascorbic Acid and Thymoquinone

Othman N, Masarudin MJ, Kuen CY, Dasuan NA, Abdullah LC, Md Jamil SNA

Nanomaterials (Basel), 2018 Nov 07;8(11).
PMID: 30405074 DOI: 10.3390/nano8110920

The combination of compounds with different classes (hydrophobic and hydrophilic characters) in single chitosan carrier is a challenge due to the hydrophilicity of chitosan. Utilization of l-ascorbic acid (LAA) and thymoquinone (TQ) compounds as effective antioxidants is marred by poor bioavailability and uptake. Nanoparticles (NPs) solved the problem by functioning as a carrier for them because they have high surface areas for more efficient delivery and uptake by cells. This research, therefore, synthesized chitosan NPs (CNPs) containing LAA and TQ, CNP-LAA-TQ via ionic gelation routes as the preparation is non-toxic. They were characterized using electron microscopy, zetasizer, UV⁻VIS spectrophotometry, and infrared spectroscopy. The optimum CNP-LAA-TQ size produced was 141.5 ± 7.8 nm, with a polydispersity index (PDI) of 0.207 ± 0.013. The encapsulation efficiency of CNP-LAA-TQ was 22.8 ± 3.2% for LAA and 35.6 ± 3.6% for TQ. Combined hydrophilic LAA and hydrophobic TQ proved that a myriad of highly efficacious compounds with poor systemic uptake could be encapsulated together in NP systems to increase their pharmaceutical efficiency, indirectly contributing to the advancement of medical and pharmaceutical sectors.
LY294002, a PI3K pathway inhibitor, prevents leptin-induced adverse effects on spermatozoa in Sprague-Dawley rats

Md Mokhtar AH, Malik IA, Abd Aziz NAA, Almabhouh FA, Durairajanayagam D, Singh HJ

Andrologia, 2019 Apr;51(3):e13196.
PMID: 30456785 DOI: 10.1111/and.13196

This study examined the effects of PI3K and AMPK signalling pathway inhibitors on leptin-induced adverse effects on rat spermatozoa. Sprague-Dawley rats, aged 14-16 weeks, were randomised into control, leptin-, leptin + dorsomorphin (AMPK inhibitor)-, and leptin+LY294002 (PI3K inhibitor)-treated groups with six rats per group. Leptin was given once daily for 14 days via the intraperitoneal (i.p.) route at a dose of 60 ug kg-1 body weight. Rats in the leptin and inhibitor-treated groups received concurrently either dorsomorphin (5 mg kg-1 day-1 ) or LY294002 (1.2 mg kg-1 day-1 ) i.p. for 14 days. Controls received 0.1 ml of normal saline. Upon completion, sperm count, sperm morphology, seminiferous tubular epithelial height (STEH), seminiferous tubular diameter (STD), 8-hydroxy-2-deoxyguanosine (8-OHdG) and phospho-Akt/total Akt ratio were estimated. Data were analysed using ANOVA. Sperm count, STEH and STD were significantly lower, while the percentage of spermatozoa with abnormal morphology and the level of 8-OHdG were significantly higher in rats treated with leptin and leptin + dorsomorphin when compared to those in controls and LY294002-treated rats. Testicular phospho-Akt/total Akt ratio was significantly higher in leptin and leptin + LY294002-treated rats. In conclusion, LY294002 prevents leptin-induced changes in rat sperm parameters, suggesting the potential role of the PI3K signalling pathway in the adverse effects of leptin on sperm parameters.
Is Malaysia's banded langur, Presbytis femoralis femoralis, actually Presbytis neglectus neglectus? Taxonomic revision with new insights on the radiation history of the Presbytis species group in Southeast Asia

Abdul-Latiff MAB, Baharuddin H, Abdul-Patah P, Md-Zain BM

Primates, 2019 Jan;60(1):63-79.
PMID: 30471014 DOI: 10.1007/s10329-018-0699-y

The disjunct distribution of Presbytis femoralis subspecies across Sumatra (P. f. percura), southern (P. f. femoralis) and northern (P. f. robinsoni) Peninsular Malaysia marks the unique vicariance events in the Sunda Shelf. However, the taxonomic positions and evolutionary history of P. f. femoralis are unresolved after decades of research. To elucidate this evolutionary history, we analyzed 501 base pairs of the mitochondrial HVSI gene from 25 individuals representing Malaysia's banded langur, with the addition of 29 sequences of Asian Presbytis from Genbank. Our results revealed closer affinity of P. f. femoralis to P. m. mitrata and P. m. sumatrana while maintaining the monophyletic state of P. f. femoralis as compared to P. f. robinsoni. Two central theses were inferred from the results; (1) P. f. femoralis does not belong in the same species classification as P. f. robinsoni, and (2) P. f. femoralis is the basal lineage of the Presbytis in Peninsular Malaysia. Proving the first hypothesis through genetic analysis, we reassigned P. f. femoralis of Malaysia to Presbytis neglectus (Schlegel's banded langur) (Schlegel in Revue Methodique, Museum d'Histoire Naturelle des Pays-Bas 7:1, 1876) following the International Code of Zoological Nomenclature (article 23.3). The ancestors of P. neglectus are hypothesized to have reached southern Peninsular Malaysia during the Pleistocene and survived in refugium along the western coast. Consequently, they radiated upward, forming P. f. robinsoni and P. siamensis resulting in the highly allopatric distribution in Peninsular Malaysia. This study has successfully resolved the taxonomic position of P. neglectus in Peninsular Malaysia while providing an alternative biogeographic theory for the Asian Presbytis.
Fulltext Emphysematous aortitis: report of two cases and CT imaging findings

Md Noh MSF, Abdul Rashid AM, Ar A, B N, Mohammed Y, A R E

BJR Case Rep, 2017;3(3):20170006.
PMID: 30363220 DOI: 10.1259/bjrcr.20170006

Emphysematous aortitis is a rare condition that manifests through the presence of air within or surrounding the inflamed aorta. Aortic inflammation may result from either an infective or a non-infective cause. Recognition of this rare condition is important as the resultant clinical deterioration may be rapid and lead to inevitable death. Cross-sectional imaging, with its relatively wide availability, proves an important tool in the diagnosis and subsequent management of this condition. We report two such cases encountered in our centre, with particular focus on the imaging findings on CT.
Postoperative major surgery patients developing silent deep vein thrombosis: A prospective observational study

Wong MP, Zahari Z, Abdullah MS, Ramely R, Md Hashim MN, Zakaria Z, et al.

J Vasc Nurs, 2018 Dec;36(4):173-180.
PMID: 30458938 DOI: 10.1016/j.jvn.2018.07.001

Surgical patients are at high risk for developing deep vein thrombosis (DVT). There are many reports concerning DVT, but little is known about silent deep vein thrombosis (sDVT). This study aimed to determine the incidence of sDVT. Secondary objective is to identify the associated factors for the use of DVT prophylaxis and Caprini risk scores among major surgery patients. This prospective observational study involved postoperative surgical patients who are at risk of developing sDVT. The Caprini risk-assessment scores were calculated, and each subject had a preoperative and postoperative compression ultrasound complemented by duplex venous ultrasonography of deep venous system. No patient from the study experienced sDVT. There were significant associations between Caprini risk score group (odds ratio, 8.16; 95% confidence interval [CI], 1.01-68.74; P = .016) and the use of central venous catheter (odds ratio, 6.34; 95% CI, 1.62-24.80; P = .008) with DVT prophylaxis. Interestingly, the use of central venous catheter resulted in more than four-point increment of Caprini risk scores (mean increment, 4.19; 95% CI, 3.16-5.21; P
Fulltext Influence of Secondary Reinforcement on Behaviour of Corbels with Various Types of High-Performance Fiber-Reinforced Cementitious Composites

Md Zin N, Al-Fakih A, Nikbakht E, Teo W, Anwar Gad M

Materials (Basel), 2019 Dec 11;12(24).
PMID: 31835775 DOI: 10.3390/ma12244159

An experimental study is conducted to determine the influence of secondary reinforcement on the behaviour of corbels fabricated with three different types of high-performance fiber-reinforced cementitious composites, including engineered cementitious concrete (ECC); high-performance steel fiber-reinforced composite (HPSFRC); and hybrid fiber-reinforced composite (HyFRC). Two shear span-to-depth ratios (a/d = 0.75 and 1.0) are explored. The mechanical properties of the composites in terms of tensile, compressive, and flexural strengths are investigated. Next, the structural behaviour of the high-performance cementitious composite corbels in terms of ultimate load capacity, ductility, and failure modes under the three-point bending test are investigated. The secondary reinforcement is proven to significantly affect stiffness and ultimately load capacity of all three high-performance composite corbels with an aspect ratio of 0.75. However, the secondary reinforcement was more impactful for the HPSFRC corbels, with 51% increase of ultimate strength. Moreover, in terms of damage, fewer cracks occurred in ECC corbels. HPSFRC corbels displayed the highest level of ductility and deformation capacity compared to the other specimens. The results were comparatively analyzed against the predicted results using truss and plastic truss models which provided relatively reliable shear strength.
Fulltext Effect of Lignin Modification on Properties of Kenaf Core Fiber Reinforced Poly(Butylene Succinate) Biocomposites

Ahmad Saffian H, Hyun-Joong K, Md Tahir P, Ibrahim NA, Lee SH, Lee CH

Materials (Basel), 2019 Dec 05;12(24).
PMID: 31817323 DOI: 10.3390/ma12244043

In this study, the effects of lignin modification on the properties of kenaf core fiber reinforced poly(butylene succinate) biocomposites were examined. A weight percent gain (WPG) value of 30.21% was recorded after the lignin were modified with maleic anhydride. Lower mechanical properties were observed for lignin composites because of incompatible bonding between the hydrophobic matrix and the hydrophilic lignin. Modified lignin (ML) was found to have a better interfacial bonding, since maleic anhydrides remove most of the hydrophilic hydrogen bonding (this was proven by a Fourier-transform infrared (FTIR) spectrometer-a reduction of broadband near 3400 cm-1, corresponding to the -OH stretching vibration of hydroxyl groups for the ML samples). On the other hand, ML was found to have a slightly lower glass transition temperature, Tg, since reactions with maleic anhydride destroy most of the intra- and inter-molecular hydrogen bonds, resulting in a softer structure at elevated temperatures. The addition of kraft lignin was found to increase the thermal stability of the PBS polymer composites, while modified kraft lignin showed higher thermal stability than pure kraft lignin and possessed delayed onset thermal degradation temperature.
Fulltext Exploring stroke survivors' self-efficacy in understanding and taking medication and determining associated factors: a cross-sectional study in a neurology clinic in Malaysia

Appalasamy JR, Joseph JP, Seeta Ramaiah S, Quek KF, Md Zain AZ, Tha KK

Patient Prefer Adherence, 2019;13:1463-1475.
PMID: 31695338 DOI: 10.2147/PPA.S215271

Background and aim: Evidence-based prescribing practices for stroke-preventive medication have benefited stroke survivors; however, medication-nonadherence rates remain high. Medication understanding and use self-efficacy (MUSE) has shown great importance in medication-taking behavior, but its relationship with medication nonadherence in stroke-preventive regimens lacks exploration. The aim of this study was to determine the prevalence of MUSE and its association with nonadherence causes and other potential factors among stroke survivors in Malaysia.
Methods: This cross-sectional study was conducted among 282 stroke patients who provided informed consent and were in follow-up at the Neurology Outpatient Department of Hospital Kuala Lumpur, Malaysia. The study employed a data-collection form that gathered information on sociodemographics, clinical treatment, outcome measures on MUSE, and medication-nonadherence reasons.
Results: The prevalence of poor medication understanding and use self-efficacy among stroke patients was 46.5%, of which 29.1% had poor "learning about medication" self-efficacy, while 36.2% lacked self-efficacy in taking medication. Beliefs about medicine (74.02%) was the commonest reason for medication nonadherence, followed by medication-management issues (44.8%). In the multivariate model, independent variables significantly associated with MUSE were health literacy (AOR 0.2, 95% CI 0.069-0.581; P=0.003), medication-management issues (AOR 0.073, 95% CI 0.020-0.266; P<0.001), multiple-medication issues (AOR 0.28, 95% CI 0.085-0.925; P=0.037), beliefs about medicine (AOR 0.131, 95% CI 0.032-0.542; P=0.005), and forgetfulness/convenience issues (AOR 0.173, 95% CI 0.050-0.600; P=0.006).
Conclusion: The relatively poor learning about medication and medication-taking self-efficacy in this study was highly associated with health literacy and modifiable behavioral issues related to nonadherence, such as medication management, beliefs about medicine, and forgetfulness/convenience. Further research ought to explore these underlying reasons using vigorous techniques to enhance medication understanding and use self-efficacy among stroke survivors to determine cause-effect relationships.
Food restriction, nutrition status, and growth in toddlers with atopic dermatitis

Low DW, Jamil A, Md Nor N, Kader Ibrahim SB, Poh BK

Pediatr Dermatol, 2020 Jan;37(1):69-77.
PMID: 31667896 DOI: 10.1111/pde.14004

BACKGROUND: Multiple factors affect growth in children with atopic dermatitis (AD). We investigated food restriction practice, nutrition, and growth in children with AD. Food restriction is defined as restriction ≥3 types of food due to AD or food allergy.
METHODS: A cross-sectional study was performed in 150 children aged 12-36 months.
EXCLUSION CRITERIA: recurrent infections, moderate to severe asthma, recent systemic steroid, other diseases affecting growth/nutrition. Growth parameters, SCORing Atopic Dermatitis (SCORAD), hemoglobin, hematocrit, sodium, potassium, albumin, protein, calcium, phosphate, B12, iron, and folate values were determined. Parents completed a 3-day food diary.
RESULTS: The prevalence of food restriction was 60.7%. Commonly restricted foods were shellfish 62.7%, nuts 53.3%, egg 50%, dairy 29.3%, and cow's milk 28.7%. Food-restricted children have significantly lower calorie, protein, fat, riboflavin, vitamin B12, calcium, phosphorus and iron intakes and lower serum iron, protein and albumin values. Z scores of weight-for-age (-1.38 ± 1.02 vs -0.59 ± 0.96, P = .00), height-for-age (-1.34 ± 1.36 vs -0.51 ± 1.22, P = .00), head circumference-for-age (-1.37 ± 0.90 vs -0.90 ± 0.81, P = .00), mid-upper arm circumference (MUAC)-for-age (-0.71 ± 0.90 vs -0.22 ± 0.88, P = .00), and BMI-for-age (-0.79 ± 1.15 vs -0.42 ± 0.99, P = .04) were significantly lower in food-restricted compared to non-food-restricted children. More food-restricted children were stunted, underweight with lower head circumference and MUAC. Severe disease was an independent risk factor for food restriction with OR 5.352; 95% CI, 2.26-12.68.
CONCLUSION: Food restriction is common in children with AD. It is associated with lower Z scores for weight, height, head circumference, MUAC, and BMI. Severe disease is an independent risk factor for food restriction.
Leptin and reproductive dysfunction in obese men

Almabhouh FA, Md Mokhtar AH, Malik IA, Aziz NAAA, Durairajanayagam D, Singh HJ

Andrologia, 2020 Feb;52(1):e13433.
PMID: 31773771 DOI: 10.1111/and.13433

Infertility is somewhat more prevalent in men who are obese. They are also reported to have low sperm concentration, higher fraction of spermatozoa that look morphologically abnormal, higher DNA fragmentation index and evidence of oxidative stress. The precise cause for this remains uncertain. Leptin levels in serum and percentage body fat correlate positively, and obese men therefore usually have elevated serum leptin levels. Although leptin is important for normal reproductive function, but when present in excess, leptin could seriously affect reproductive function in men. Reports on the findings of sperm parameters in obese men, particularly those who are subfertile or infertile, seem to be similar to those reported from studies on normal-weight rats treated with leptin. Collectively, the observations reported in human and experimental animal studies point to leptin as a possible link between infertility and obesity. Herein, we review some findings on sperm function in obese subfertile or infertile men and those from animal studies following leptin treatment, and discuss the possible link between leptin and reproductive dysfunction in obese men. The large amounts of leptin secreted by the adipose tissue and its higher circulating levels could indeed be responsible for the higher prevalence of infertility in obese men.
Impacts of morphological-controlled ZnO nanoarchitectures on aerobic microbial communities during real wastewater treatment in an aerobic-photocatalytic system

Chang JS, Chong MN, Poh PE, Ocon JD, Md Zoqratt MZH, Lee SM

Environ Pollut, 2020 Apr;259:113867.
PMID: 31896479 DOI: 10.1016/j.envpol.2019.113867

This study aimed to evaluate the impacts of morphological-controlled ZnO nanoarchitectures on aerobic microbial communities during real wastewater treatment in an aerobic-photocatalytic system. Results showed that the antibacterial properties of ZnO nanoarchitectures were significantly more overwhelming than their photocatalytic properties. The inhibition of microbial activities in activated sludge by ZnO nanoarchitectures entailed an adverse effect on wastewater treatment efficiency. Subsequently, the 16S sequencing analysis were conducted to examine the impacts of ZnO nanoarchitectures on aerobic microbial communities, and found the significantly lower microbial diversity and species richness in activated sludge treated with 1D-ZnO nanorods as compared to other ZnO nanoarchitectures. Additionally, 1D-ZnO nanorods reduced the highest proportion of Proteobacteria phylum in activated sludge due to its higher proportion of active polar surfaces that facilitates Zn2+ ions dissolution. Pearson correlation coefficients showed that the experimental data obtained from COD removal efficiency and bacterial log reduction were statistically significant (p-value
Fulltext Edible Bird's Nest Protects Against Hyperglycemia-Induced Oxidative Stress and Endothelial Dysfunction

Murugan DD, Md Zain Z, Choy KW, Zamakshshari NH, Choong MJ, Lim YM, et al.

Front Pharmacol, 2019;10:1624.
PMID: 32116666 DOI: 10.3389/fphar.2019.01624

Increased oxidative stress by hyperglycemia is a major cause of vascular complications in diabetes. Bird's nest, which is made from the saliva of swiftlets has both medicinal and nutritional values dated back to ancient China. However, its role in improving endothelial dysfunction due to diabetes is yet to be elucidated. The present study examined the protective effect and mechanism of action of the aqueous extract of hydrolyzed edible bird nest (HBN) on endothelium in models of diabetes, in vitro and in vivo. Male db/m+ and db/db mice were orally administered with or without HBN and glibenclamide for 28 days, followed by vascular reactivity studies in mouse aortas. Human umbilical vein endothelial cells (HUVECs) and isolated mouse aorta from C57BL/6J were treated with high glucose (HG), HBN, sialic acid (SA), glibenclamide, and apocynin, respectively. The effects of HBN on reactive oxygen species (ROS) production and nitric oxide (NO) bioavailability were assessed by Western blot, 2',7'-dichlorofluorescin-diacetate (DCF-DA), and 4-amino-5-methylamino-2',7' difluorofluorescein (DAF-FM DA) in HUVECs, isolated mouse aorta, and db/db diabetic mice. HBN significantly reversed the endothelial dysfunction in diabetic mice and isolated mouse aorta. HBN normalized ROS over-production of NOX2 and nitrotyrosine, reversed the reduction of anti-oxidant marker, SOD-1 as well as restored NO bioavailability in both HUVECs challenged with HG and in db/db diabetic mice. Similarly, HG-induced elevation of oxidative stress in HUVECs were reversed by SA, glibenclamide, and apocynin. This attests that HBN restores endothelial function and protects endothelial cells against oxidative damage induced by HG in HUVECs, isolated mouse aorta, and db/db diabetic mice via modulating ROS mechanism, which subsequently increases NO bioavailability. This result demonstrates the potential role of HBN in preserving endothelial function and management of micro- or macrovascular complications in diabetes.
Nutritional and bone health status in young men with mild-to-moderate intellectual disability and without intellectual disability residing in community setting in Malaysia

Jamil NA, Jia Ling C, Md Ibrahim HI, Hamzaid NH, Kok Yong C

J Appl Res Intellect Disabil, 2020 May;33(3):632-639.
PMID: 32080943 DOI: 10.1111/jar.12708

BACKGROUND: This study aimed to compare the nutritional and bone health status between young men with mild-to-moderate intellectual disability and those without intellectual disability and to determine predictors for their bone health status.
METHOD: A total of 95 men (47 men with intellectual disability; 48 men without intellectual disability), aged 20-39 years, participated in this study. Anthropometric profile, dietary intake, physical activity level and calcaneal speed of sound (SOS) were collected.
RESULTS: The men with intellectual disability had moderate diet quality whilst the men without intellectual disability had poor diet quality. More participants with intellectual disability (97.9%) were inactive compared with their counterparts (10.4%). The SOS value was similar between groups and was lower than the reference. Increasing age and low physical activity level were negative predictors for bone health status.
CONCLUSION: Both young men with and without intellectual disability have suboptimal nutritional and bone health status. Strategies to improve their nutritional and bone health status are warranted.
Gold nano-urchin integrated label-free amperometric aptasensing human blood clotting factor IX: A prognosticative approach for "Royal disease"

Letchumanan I, Gopinath SCB, Md Arshad MK, Anbu P, Lakshmipriya T

Biosens Bioelectron, 2019 Apr 15;131:128-135.
PMID: 30826647 DOI: 10.1016/j.bios.2019.02.006

This article is clearly presenting the development of a biosensor for human factor IX (FIX) to diagnose the blood clotting deficiency, a so-called 'Royal disease' using an interdigitated electrode (IDE) with the zinc oxide surface modification. Gold nano-urchins (GNUs) with 60 nm in diameter was integrated into a streptavidin-biotinylated aptamer strategy to enhance the active surface area. Two different comparative studies have been done to validate the system to be practiced in the current work holds with a higher capability for the high-performance sense. Whereby, the presence and absence of GNUs in the aptasensing system for FIX interaction were investigated using the amperometric measurement, using a linear sweep voltage of 0-2 V at 0.01 V step voltage. The detection limit was 6 pM based on 3σ calculation when GNUs integrated aptamer assay was utilized for FIX detection, which shows 8 folds sensitivity enhancement comparing the condition in the absence of GNU and 50 folds higher than sensitive radio-isotope and surface plasmon resonance assays. Albeit, the surface and molecular characterizations were well demonstrated by scanning electron microscopy, atomic force microscopy, 3D nano-profilometry and further supports were rendered by UV-Vis spectroscopy and Enzyme-linked apta-sorbent assay (ELASA). Furthermore, the spiking experiment was done by FIX-spikes in human blood serum in order to demonstrate the stability with a higher non-fouling.
Fulltext Real Time Microwave Biochemical Sensor Based on Circular SIW Approach for Aqueous Dielectric Detection

Mohd Bahar AA, Zakaria Z, Md Arshad MK, Isa AAM, Dasril Y, Alahnomi RA

Sci Rep, 2019 04 02;9(1):5467.
PMID: 30940843 DOI: 10.1038/s41598-019-41702-3

In this study, a critical evaluation of analyte dielectric properties in a microvolume was undertaken, using a microwave biochemical sensor based on a circular substrate integrated waveguide (CSIW) topology. These dielectric properties were numerically investigated based on the resonant perturbation method, as this method provides the best sensing performance as a real-time biochemical detector. To validate these findings, shifts of the resonant frequency in the presence of aqueous solvents were compared with an ideal permittivity. The sensor prototype required a 2.5 µL volume of the liquid sample each time, which still offered an overall accuracy of better than 99.06%, with an average error measurement of ±0.44%, compared with the commercial and ideal permittivity values. The unloaded Qu factor of the circular substrate-integrated waveguide (CSIW) sensor achieved more than 400 to ensure a precise measurement. At 4.4 GHz, a good agreement was observed between simulated and measured results within a broad frequency range, from 1 to 6 GHz. The proposed sensor, therefore, offers high sensitivity detection, a simple structural design, a fast-sensing response, and cost-effectiveness. The proposed sensor in this study will facilitate real improvements in any material characterization applications such as pharmaceutical, bio-sensing, and food processing applications.
Diagnosis of cancer is not a death sentence: Examining posttraumatic growth and its associated factors in cancer patients

Leong Abdullah MFI, Hami R, Appalanaido GK, Azman N, Mohd Shariff N, Md Sharif SS

J Psychosoc Oncol, 2019 03 01;37(5):636-651.
PMID: 30821660 DOI: 10.1080/07347332.2019.1574946

Objectives: Posttraumatic growth (PTG) is the experience of positive psychological growth as a result of struggle with highly challenging life crises. This study was conducted to investigate the degree of PTG and its associated factors, as well as to identify which positive psychological parameters most significantly associated with greater PTG among Malaysian cancer patients. Design, sample, & methods: This cross-sectional survey included 195 patients with different cancer diagnoses. Perceived spousal support, level of hope, level of optimism, and PTG were measured using various validated indexes. Findings: The total mean score for PTG Inventory-Short Form (PTGI-SF) was 39.87 (±9.09). Female gender, Islamic religious belief, and having higher level of hope and greater spousal support were associated with a higher PTGI-SF score, and the most significant predictor was the hope scale. Conclusions: Malaysian cancer patients exhibited a high level of PTG, and hope was the positive psychological factor which was most significantly associated with PTG. Implications for psychosocial providers: Psychosocial interventions that promote positive psychology should be included in the treatment for cancer patients.
Fulltext Zinc/Aluminium⁻Quinclorac Layered Nanocomposite Modified Multi-Walled Carbon Nanotube Paste Electrode for Electrochemical Determination of Bisphenol A

Zainul R, Abd Azis N, Md Isa I, Hashim N, Ahmad MS, Saidin MI, et al.

Sensors (Basel), 2019 Feb 22;19(4).
PMID: 30813385 DOI: 10.3390/s19040941

This paper presents the application of zinc/aluminium-layered double hydroxide-quinclorac (Zn/Al-LDH-QC) as a modifier of multiwalled carbon nanotubes (MWCNT) paste electrode for the determination of bisphenol A (BPA). The Zn/Al-LDH-QC/MWCNT morphology was examined by a transmission electron microscope and a scanning electron microscope. Electrochemical impedance spectroscopy was utilized to investigate the electrode interfacial properties. The electrochemical responses of the modified electrode towards BPA were thoroughly evaluated by using square-wave voltammetry technique. The electrode demonstrated three linear plots of BPA concentrations from 3.0 × 10-8⁻7.0 × 10-7 M (R² = 0.9876), 1.0 × 10-6⁻1.0 × 10-5 M (R² = 0.9836) and 3.0 × 10-5⁻3.0 × 10-4 M (R² = 0.9827) with a limit of detection of 4.4 × 10-9 M. The electrode also demonstrated good reproducibility and stability up to one month. The presence of several metal ions and organic did not affect the electrochemical response of BPA. The electrode is also applicable for BPA determination in baby bottle and mineral water samples with a range of recovery between 98.22% and 101.02%.
Current and future envision on developing biosensors aided by 2D molybdenum disulfide (MoS2) productions

Dalila R N, Md Arshad MK, Gopinath SCB, Norhaimi WMW, Fathil MFM

Biosens Bioelectron, 2019 May 01;132:248-264.
PMID: 30878725 DOI: 10.1016/j.bios.2019.03.005

Two-dimensional (2D) layered nanomaterials have triggered an intensive interest due to the fascinating physiochemical properties with the exceptional physical, optical and electrical characteristics that transpired from the quantum size effect of their ultra-thin structure. Among the family of 2D nanomaterials, molybdenum disulfide (MoS2) features distinct characteristics related to the existence of direct energy bandgap, which significantly lowers the leakage current and surpasses other 2D materials. In this overview, we expatiate the novel strategies to synthesize MoS2 that cover techniques such as liquid exfoliation, chemical vapour deposition, mechanical exfoliation, hydrothermal reaction, and Van Der Waal epitaxial growth on the substrate. We extend the discussion on the recent progress in biosensing applications of the produced MoS2, highlighting the important surface-to-volume of ultrathin MoS2 structure, which enhances the overall performance of the devices. Further, envisioned the missing piece with the current MoS2-based biosensors towards developing the future strategies.

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