MyMedR

Displaying publications 1 - 20 of 56 in total

Abstract:

Sort:

From defense to offense: Modulating toll-like receptors to combat arbovirus infections

Lani R, Thariq IM, Suhaimi NS, Hassandarvish P, Abu Bakar S

Hum Vaccin Immunother, 2024 Dec 31;20(1):2306675.
PMID: 38263674 DOI: 10.1080/21645515.2024.2306675

Arboviruses are a significant threat to global public health, with outbreaks occurring worldwide. Toll-like receptors (TLRs) play a crucial role in the innate immune response against these viruses by recognizing pathogen-associated molecular patterns and initiating an inflammatory response. Significantly, TLRs commonly implicated in the immune response against viral infections include TLR2, TLR4, TLR6, TLR3, TLR7, and TLR8; limiting or allowing them to replicate and spread within the host. Modulating TLRs has emerged as a promising approach to combat arbovirus infections. This review summarizes recent advances in TLR modulation as a therapeutic target in arbovirus infections. Studies have shown that the activation of TLRs can enhance the immune response against arbovirus infections, leading to increased viral clearance and protection against disease. Conversely, inhibition of TLRs can reduce the excessive inflammation and tissue damage associated with arbovirus infection. Modulating TLRs represents a potential therapeutic strategy to combat arbovirus infections.
Seroprevalence of dengue and chikungunya viruses among urban refugees in Klang Valley, Malaysia

Sahimin N, Low ZX, Hassandarvish P, Mohd Hanapi IR, Mohd Zain SN, Yahaya H, et al.

Trans R Soc Trop Med Hyg, 2024 Jan 16.
PMID: 38226501 DOI: 10.1093/trstmh/trad097

BACKGROUND: Mosquito-borne diseases pose a significant global public health threat, with Malaysia's Klang Valley experiencing numerous outbreaks in densely populated urban areas.
METHODS: This study aimed to estimate the seroprevalence of anti-dengue and anti-chikungunya antibodies among urban refugees in the Klang Valley, Malaysia, and identify associated risk factors.
RESULTS: High seroprevalence of anti-dengue immunoglobulin G (IgG) and IgM (60.0% [confidence interval {CI} 55.39 to 64.48] and 9.2% [CI 6.77 to 12.25], respectively) were observed among refugees >18 years of age (χ22=11.720, p=0.003), Kachin ethnicity (χ28=72.253, p<0.001), without formal education (χ21=3.856, p=0.050), homes near waste disposal sites (χ21=10.378, p=0.001) and refugees who have experienced flooding (χ21=5.460, p=0.019). Meanwhile, the overall seroprevalence of anti-chikungunya IgG and IgM was 9.7% (CI 7.15 to 12.73) and 10.8% (CI 8.09 to 13.93), respectively, with ages 12-18 years (χ22=6.075, p=0.048), Rohingya ethnicity (χ28=31.631, p<0.001) and homes close to waste disposal sites (χ21=3.912, p=0.048) being significant risk factors. Results showed a link to poor environmental living conditions, with an increase in the vector population with higher availability of breeding sites and thus exposure to dengue and chikungunya virus.
CONCLUSIONS: Health education among the community is the key to disease prevention, as there are no specific antiviral drugs for treatment and limited vaccine availability.
Fulltext Effect of Carcinomas on Autosomal Trait Screening: A Review Article

Alhatim H, Abdullah MNH, Abu Bakar S, Amer SA

Curr Issues Mol Biol, 2023 Sep 04;45(9):7275-7285.
PMID: 37754244 DOI: 10.3390/cimb45090460

This review highlights the effect of carcinomas on the results of the examination of autosomal genetic traits for identification and paternity tests when carcinoid tissue is the only source and no other samples are available. In DNA typing or genetic fingerprinting, variable elements are isolated and identified within the base pair sequences that form the DNA. The person's probable identity can be determined by analysing nucleotide sequences in particular regions of DNA unique to everyone. Genetics plays an increasingly important role in the risk stratification and management of carcinoma patients. The available information from previous studies has indicated that in some incidents, including mass disasters and crimes such as terrorist incidents, biological evidence may not be available at the scene of the accident, except for some unknown human remains found in the form of undefined human tissues. If these tissues have cancerous tumours, it may affect the examination of the genetic traits derived from these samples, thereby resulting in a failure to identify the person. Pathology units, more often, verify the identity of the patients who were diagnosed with cancer in reference to their deceased tumorous relatives. Genetic fingerprinting (GF) is also used in paternity testing when the alleged parent disappeared or died and earlier was diagnosed and treated for cancer.
Fulltext Supraglottic Foreign Body Missed for One Month in a Child

Sultan Abdul Kader MI, Syafeera N, Md Nor K, Abu Bakar S, Mat Baki M

Cureus, 2023 Jan;15(1):e33870.
PMID: 36819404 DOI: 10.7759/cureus.33870

Foreign body (FB) aspiration in children can result in serious complications that can lead to even death. We present a case of a one-year-old girl child with a history of choking one month prior while she was feeding. A bolus of rice was removed at a local clinic. Consequently, within 24 hours, she developed hoarseness and noisy breathing which was treated as an upper respiratory tract infection at two different clinics. This case report aims to highlight the need for otolaryngology consultation in a child with non-resolving respiratory symptoms following episodes of choking. This will prompt an immediate surgical intervention that could prevent potential morbidity and mortality as a result of a compromised airway.
Fulltext A multicentre study to determine the in vitro efficacy of flomoxef against extended-spectrum beta-lactamase producing Escherichia coli in Malaysia

Yap PSX, Chong CW, Ponnampalavanar S, Ramli R, Harun A, Tengku Jamaluddin TZM, et al.

PeerJ, 2023;11:e16393.
PMID: 38047021 DOI: 10.7717/peerj.16393

BACKGROUND: The high burden of extended-spectrum beta-lactamase-producing (ESBL)-producing Enterobacterales worldwide, especially in the densely populated South East Asia poses a significant threat to the global transmission of antibiotic resistance. Molecular surveillance of ESBL-producing pathogens in this region is vital for understanding the local epidemiology, informing treatment choices, and addressing the regional and global implications of antibiotic resistance.
METHODS: Therefore, an inventory surveillance of the ESBL-Escherichia coli (ESBL-EC) isolates responsible for infections in Malaysian hospitals was conducted. Additionally, the in vitro efficacy of flomoxef and other established antibiotics against ESBL-EC was evaluated.
RESULTS: A total of 127 non-repetitive ESBL-EC strains isolated from clinical samples were collected during a multicentre study performed in five representative Malaysian hospitals. Of all the isolates, 33.9% were isolated from surgical site infections and 85.8% were hospital-acquired infections. High rates of resistance to cefotaxime (100%), cefepime (100%), aztreonam (100%) and trimethoprim-sulfamethoxazole (100%) were observed based on the broth microdilution test. Carbapenems remained the most effective antibiotics against the ESBL-EC, followed by flomoxef. Antibiotic resistance genes were identified by PCR. The blaCTX-M-1 was the most prevalent ESBL gene, with 28 isolates (22%) harbouring blaCTX-M-1 only, 27 isolates (21.3%) co-harbouring blaCTX-M-1 and blaTEM, and ten isolates (7.9%) co-harbouring blaCTX-M-1, blaTEM and blaSHV. A generalised linear model showed significant antibacterial activity of imipenem against different types of infection. Besides carbapenems, this study also demonstrated a satisfactory antibacterial activity of flomoxef (81.9%) on ESBL-EC, regardless of the types of ESBL genes.
Mitochondrial Diversity of the Asian Tiger Mosquito Aedes albopictus (Diptera: Culicidae) in Peninsular Malaysia

Misbah S, Low VL, Mohd Rahim NF, Jaba R, Basari N, Ya'cob Z, et al.

J Med Entomol, 2022 Feb 18.
PMID: 35178576 DOI: 10.1093/jme/tjac014

Aedes albopictus is one of the main mosquito vectors responsible for transmitting arboviruses to humans and animals. The ability of this mosquito to support virus transmission has been linked to vector competence, which is partly attributed to the genetic disparities in Ae. albopictus population. At present, little is known about the biologically important traits of Ae. albopictus in Malaysia. Thus, the study aims to determine the genetic variation of Ae. albopictus based on the mitochondria-encoded sequences of cytochrome oxidase subunit I (COI). A statistical parsimony network of 253 taxa aligned as 321 characters of the COI gene revealed 42 haplotypes (H1-H42), of which H1 was the most widespread haplotype in Peninsular Malaysia. Three highly divergent haplotypes (H21, H30, and H31) were detected from the northern population. Overall, haplotype and nucleotide diversities were 0.576 and 0.003, respectively, with low genetic differentiation (FST = 0.039) and high gene flow (Nm = 12.21) across all populations.
Fulltext Virulence Gene Profile, Antimicrobial Resistance and Multilocus Sequence Typing of Salmonella enterica Subsp. enterica Serovar Enteritidis from Chickens and Chicken Products

Zakaria Z, Hassan L, Sharif Z, Ahmad N, Mohd Ali R, Amir Husin S, et al.

Animals (Basel), 2022 Jan 01;12(1).
PMID: 35011203 DOI: 10.3390/ani12010097

This study was undertaken to determine the virulence, antimicrobial resistance and molecular subtypes of Salmonella in the Central Region of Peninsular Malaysia. A total of 45 Salmonella Enteritidis were detected from live chicken (cloacal swab), and chicken products (fresh and ready-to-eat meat) samples upon cultural isolation and serotyping. Similarly, an antimicrobial susceptibility test based on the Kirby Bauer disk diffusion method as well as antimicrobial resistance AMR genes, virulence determinants and multilocus sequence typing (MLST) typing were conducted after the Whole Genome Sequencing and analysis of the isolates. The results indicate that sequence types ST1925 (63.7%), and ST11 (26.5%) were the predominant out of the seven sequence types identified (ST292, ST329, ST365, ST423 and ST2132). The phenotypic antimicrobial profile corresponds to the genotypic characterization in that the majority of the isolates that exhibited tetracycline, gentamycin and aminoglycoside resistance; they also possessed the tetC and blaTEM β-Lactam resistance genes. However, isolates from cloacal swabs showed the highest number of resistance genes compared to the chicken products (fresh and ready-to-eat meat) samples. Furthermore, most of the virulence genes were found to cluster in the Salmonella pathogenicity island (SPI). In this study, all the isolates were found to possess SPI-1, which codes for the type III secretion system, which functions as actin-binding proteins (SptP and SopE). The virulence plasmid (VP) genes (spvB, spvC) were present in all genotypes except ST365. The findings of this study, particularly with regard to the molecular subtypes and AMR profiles of the Salmonella Enteritidis serotype shows multidrug-resistance features as well as genetic characteristics indicative of high pathogenicity.
Fulltext Quantification of Gait Stability During Incline and Decline Walking: The Responses of Required Coefficient of Friction and Dynamic Postural Index

Abdul Yamin NAA, Basaruddin KS, Abu Bakar S, Salleh AF, Mat Som MH, Yazid H, et al.

J Healthc Eng, 2022;2022:7716821.
PMID: 36275397 DOI: 10.1155/2022/7716821

This study aims to investigate the gait stability response during incline and decline walking for various surface inclination angles in terms of the required coefficient of friction (RCOF), postural stability index (PSI), and center of pressure (COP)-center of mass (COM) distance. A customized platform with different surface inclinations (0°, 5°, 7.5°, and 10°) was designed. Twenty-three male volunteers participated by walking on an inclined platform for each inclination. The process was then repeated for declined platform as well. Qualysis motion capture system was used to capture and collect the trajectories motion of ten reflective markers that attached to the subjects before being exported to a visual three-dimensional (3D) software and executed in Matlab to obtain the RCOF, PSI, as well as dynamic PSI (DPSI) and COP-COM distance parameters. According to the result for incline walking, during initial contact, the RCOF was not affected to inclination. However, it was affected during peak ground reaction force (GRF) starting at 7.5° towards 10° for both walking conditions. The most affected PSI was found at anterior-posterior PSI (APSI) even as low as 5° inclination during both incline and decline walking. On the other hand, DPSI was not affected during both walking conditions. Furthermore, COP-COM distance was most affected during decline walking in anterior-posterior direction. The findings of this research indicate that in order to decrease the risk of falling and manage the inclination demand, a suitable walking strategy and improved safety measures should be applied during slope walking, particularly for decline and anterior-posterior orientations. This study also provides additional understanding on the best incline walking technique for secure and practical incline locomotion.
Carboxymethyl Cellulose Hydrogel Based Formulations of Zinc Hydroxide Nitrate-Sodium Dodecylsulphate-Bispyribac Nanocomposite: Advancements in Controlled Release Formulation of Herbicide

Mohd Sharif SN, Hashim N, Md Isa I, Abu Bakar S, Idris Saidin M, Syahrizal Ahmad M, et al.

J Nanosci Nanotechnol, 2021 12 01;21(12):5867-5880.
PMID: 34229781 DOI: 10.1166/jnn.2021.19499

The usefulness of carboxymethyl cellulose (CMC) as a matrix material in enhancing the controlled release formulations of bispyribac (BP) herbicide from the interlayer gallery of zinc hydroxide nitratesodium dodecylsulphate-bispyribac (ZHN-SDS-BP) nanocomposite was investigated. The CMC coated nanocomposite, ZHN-SDS-BP-CMC was characterised using several instruments for the determination of its physicochemical properties. The release rates of the BP were measured using a UV spectrophotometer, and the aqueous solutions containing PO3-₄ , SO2-₄ and Cl- were selected as release media in the release studies so as to mimic the real conditions of environmental soil. Significant release time delays, triggered by the gelation forming ability and hygroscopic nature of CMC, were observed in all release media, and the release processes were found to behave in a concentration-dependent manner in all release media. Fitting the release data into several kinetic models demonstrated that release in aqueous solutions of Na₃PO₄ and Na₂SO₄ was governed by pseudo second order processes, whereas the release in an aqueous NaCl solution was governed by the parabolic diffusion kinetic model. The potential of CMC in prolonging the release of BP from ZHN-SDS-BP-CMC can potentially help in reducing the pollution resulting from the overuse of pesticides.
Fulltext Optimization of a High-Performance Poly(diallyl dimethylammonium chloride)-alumina-perfluorooctanoate Intercalated Ultrafiltration Membrane for Treating Emulsified Oily Wastewater via Response Surface Methodology Approach

Raji YO, Othman MHD, Nordin NAHSM, Adam MR, Said KAM, Abdulyekeen KA, et al.

Membranes (Basel), 2021 Dec 01;11(12).
PMID: 34940457 DOI: 10.3390/membranes11120956

This research aimed to investigate the ultrafiltration of water from emulsified oily wastewater through the application of surface-functionalized ceramic membrane to enhance its water permeability based on optimized parameters using a cross-flow filtration system. The interactive effects of feed concentration (10-1000 ppm), pH (4-10), and pressure (0-3 bar) on the water flux and oil rejection were investigated. Central composite design (CCD) from response surface methodology (RSM) was employed for statistical analysis, modeling, and optimization of operating conditions. The analysis of variance (ANOVA) results showed that the oil rejection and water flux models were significant with p-values of 0.0001 and 0.0075, respectively. In addition, good correlation coefficients of 0.997 and 0.863 were obtained for the oil rejection and water flux models, respectively. The optimum conditions for pressure, pH, and feed concentration were found to be 1.5 bar, pH 8.97, and 10 ppm, respectively with water flux and oil rejection maintained at 152 L/m2·h and 98.72%, respectively. Hence, the functionalized ultrafiltration ceramic membrane enables the separation efficiency of the emulsified oil in water to be achieved.
Carbon nanotubes from waste cooking palm oil as adsorbent materials for the adsorption of heavy metal ions

Abu Bakar S, Jusoh N, Mohamed A, Muqoyyanah M, Othman MHD, Mamat MH, et al.

Environ Sci Pollut Res Int, 2021 Dec;28(46):65171-65187.
PMID: 34231144 DOI: 10.1007/s11356-021-14918-y

In this work, waste cooking palm oil (WCPO)-based carbon nanotubes (CNTs) with encapsulated iron (Fe) nanoparticles have been successfully produced via modified thermal chemical vapor deposition method. Based on several characterizations, the dense WCPO-based CNT was produced with high purity of 89% and high crystallinity proven by low ID/IG ratio (0.43). Moreover, the ferromagnetic response of CNTs showed that the average coercivity and magnetization saturation were found to be 551.5 Oe and 13.4 emu/g, respectively. These produced WCPO-based CNTs were further used as heavy metal ions adsorbent for wastewater treatment application. Some optimizations, such as the effect of different adsorbent dosage, varied initial pH solution, and various heavy metal ions, were investigated. The adsorption studies showed that the optimum adsorbent dosage was 1.8 g/L when it was applied to 100 mg/L Cu (II) solution at neutral pH (pH 7). Further measurement then showed that high Cu (II) ion removal percentage (~80%) was achieved when it was applied at very acidic solution (pH 2). Last measurement confirmed that the produced WCPO-based CNTs successfully removed different heavy metal ions in the following order: Fe (II) > Zn (II) ≈ Cu (II) with the removal percentage in the range of 99.2 to 99.9%. The adsorption isotherm for Cu (II) was better fitted by Langmuir model with a correlation coefficient of 0.82751. WCPO-based CNTs can be a potential material to be applied as adsorbent in heavy metal ion removal.
Fulltext The Influence of Traffic-Related Air Pollution (TRAP) in Primary Schools and Residential Proximity to Traffic Sources on Histone H3 Level in Selected Malaysian Children

Suhaimi NF, Jalaludin J, Abu Bakar S

Int J Environ Res Public Health, 2021 07 28;18(15).
PMID: 34360284 DOI: 10.3390/ijerph18157995

This study aimed to investigate the association between traffic-related air pollution (TRAP) exposure and histone H3 modification among school children in high-traffic (HT) and low-traffic (LT) areas in Malaysia. Respondents' background information and personal exposure to traffic sources were obtained from questionnaires distributed to randomly selected school children. Real-time monitoring instruments were used for 6-h measurements of PM10, PM2.5, PM1, NO2, SO2, O3, CO, and total volatile organic compounds (TVOC). Meanwhile, 24-h measurements of PM2.5-bound black carbon (BC) were performed using air sampling pumps. The salivary histone H3 level was captured using an enzyme-linked immunosorbent assay (ELISA). HT schools had significantly higher PM10, PM2.5, PM1, BC, NO2, SO2, O3, CO, and TVOC than LT schools, all at p < 0.001. Children in the HT area were more likely to get higher histone H3 levels (z = -5.13). There were positive weak correlations between histone H3 level and concentrations of NO2 (r = 0.37), CO (r = 0.36), PM1 (r = 0.35), PM2.5 (r = 0.34), SO2 (r = 0.34), PM10 (r = 0.33), O3 (r = 0.33), TVOC (r = 0.25), and BC (r = 0.19). Overall, this study proposes the possible role of histone H3 modification in interpreting the effects of TRAP exposure via non-genotoxic mechanisms.
Deoxyribonucleic acid (DNA) methylation in children exposed to air pollution: a possible mechanism underlying respiratory health effects development

Suhaimi NF, Jalaludin J, Abu Bakar S

Rev Environ Health, 2021 Mar 26;36(1):77-93.
PMID: 32857724 DOI: 10.1515/reveh-2020-0065

Air pollution is a substantial environmental threat to children and acts as acute and chronic disease risk factors alike. Several studies have previously evaluated epigenetic modifications concerning its exposure across various life stages. However, findings on epigenetic modifications as the consequences of air pollution during childhood are rather minimal. This review evaluated highly relevant studies in the field to analyze the existing literature regarding exposure to air pollution, with a focus on epigenetic alterations during childhood and their connections with respiratory health effects. The search was conducted using readily available electronic databases (PubMed and ScienceDirect) to screen for children's studies on epigenetic mechanisms following either pre- or post-natal exposure to air pollutants. Studies relevant enough and matched the predetermined criteria were chosen to be reviewed. Non-English articles and studies that did not report both air monitoring and epigenetic outcomes in the same article were excluded. The review found that epigenetic changes have been linked with exposure to air pollutants during early life with evidence and reports of how they may deregulate the epigenome balance, thus inducing disease progression in the future. Epigenetic studies evolve as a promising new approach in deciphering the underlying impacts of air pollution on deoxyribonucleic acid (DNA) due to links established between some of these epigenetic mechanisms and illnesses.
Fulltext Exposure to Particulate PAHs on Potential Genotoxicity and Cancer Risk among School Children Living Near the Petrochemical Industry

Sopian NA, Jalaludin J, Abu Bakar S, Hamedon TR, Latif MT

Int J Environ Res Public Health, 2021 03 04;18(5).
PMID: 33806616 DOI: 10.3390/ijerph18052575

This study aimed to assess the association of exposure to particle-bound (PM2.5) polycyclic aromatic hydrocarbons (PAHs) with potential genotoxicity and cancer risk among children living near the petrochemical industry and comparative populations in Malaysia. PM2.5 samples were collected using a low-volume sampler for 24 h at three primary schools located within 5 km of the industrial area and three comparative schools more than 20 km away from any industrial activity. A gas chromatography-mass spectrometer was used to determine the analysis of 16 United States Environmental Protection Agency (USEPA) priority PAHs. A total of 205 children were randomly selected to assess the DNA damage in buccal cells, employing the comet assay. Total PAHs measured in exposed and comparative schools varied, respectively, from 61.60 to 64.64 ng m-3 and from 5.93 to 35.06 ng m-3. The PAH emission in exposed schools was contributed mainly by traffic and industrial emissions, dependent on the source apportionment. The 95th percentiles of the incremental lifetime cancer risk estimated using Monte Carlo simulation revealed that the inhalation risk for the exposed children and comparative populations was 2.22 × 10-6 and 2.95 × 10-7, respectively. The degree of DNA injury was substantially more severe among the exposed children relative to the comparative community. This study reveals that higher exposure to PAHs increases the risk of genotoxic effects and cancer among children.
Ethnicity as predictor of immune reconstitution among Malaysian HIV-positive patients treated with highly active antiretroviral therapy

Mohamad Isa II, Abu Bakar S, Ab Rahman AK

J Med Virol, 2020 08;92(8):1173-1181.
PMID: 31957025 DOI: 10.1002/jmv.25680

The impact of sociodemographic and clinical factors on immune recovery and viral load suppression among HIV-1 positive patients treated with HAART particularly in Malaysia is largely unknown. This cross-sectional study enrolled 170 HIV-1-infected individuals of three major ethnicities who attended three HIV outpatient clinics in Malaysia. Questionnaire was used to obtain sociodemographic data while CD4 count and viral load data were gathered from hospital's record. Multiple factors were assessed for their predictive effects on CD4 count recovery (≥500 cells/mm3 ) and viral load suppression (≤50 copies/mL) using binary logistic regression. Most of the subjects were male (149/87.6%), in the age group 30 to 39 years old (78/45.9%) and got infected via homosexual contact (82/48.2%). Indians were associated with 11 times higher chance for CD4 recovery as compared to Malays at 8 to 12 months of HAART (adjusted OR: 10.948, 95% CI: 1.873, 64.001, P = .008). Viral load suppression was positively influenced by intravenous drug use (IVDU) status (adjusted OR: 35.224, 95% CI: 1.234, 1000.489, P = .037) at 4 to 6 months of HAART. Higher pretreatment CD4 count was a positive predictor for both initial immunological and virological responses while higher pretreatment viral load was a negative predictor for virological suppression only. In conclusion, ethnicity plays a significant role in determining early immune reconstitution in Malaysia, besides pretreatment CD4 count. Further studies are needed to identify possible biological factors underlying this association.
Highly branched triple-chain surfactant-mediated electrochemical exfoliation of graphite to obtain graphene oxide: colloidal behaviour and application in water treatment

Jamaluddin NA, Mohamed A, Abu Bakar S, Ardyani T, Sagisaka M, Suhara S, et al.

Phys Chem Chem Phys, 2020 Jun 14;22(22):12732-12744.
PMID: 32462145 DOI: 10.1039/d0cp01243b

The generation of surfactant-assisted exfoliated graphene oxide (sEGO) by electrochemical exfoliation is influenced by the presence of surfactants, and in particular the hydrophobic tail molecular-architecture. Increasing surfactant chain branching may improve the affinity for the graphite surfaces to provide enhanced intersheet separation and stabilisation of exfoliated sheets. The resulting sEGO composites can be readily used to remove of a model pollutant, the dye, methylene blue (MB), from aqueous solutions by providing abundant sites for dye adsorption. This article explores relationships between surfactant structure and the performance of sEGO for MB adsorption. Double-branched and highly branched triple-chain graphene-compatible surfactants were successfully synthesised and characterised by 1H NMR spectroscopy. These surfactants were used to produce sEGO via electrochemical exfoliation of graphite, and the sEGOs generated were further utilised in batch adsorption studies of MB from aqueous solutions. The properties of these synthesised surfactants were compared with those of a common single-chain standard surfactant, sodium dodecyl-sulfate (SDS). The structural morphology of sEGO was assessed using Raman spectroscopy and field emission scanning electron microscopy (FESEM). To reveal the links between the hydrophobic chain structure and the sEGO adsorption capacity, UV-visible spectroscopy, zeta potential, and air-water (a/w) surface tension measurements were conducted. The aggregation behaviour of the surfactants was studied using small-angle neutron scattering (SANS). The highly branched triple-chain surfactant sodium 1,4-bis(neopentyloxy)-3-(neopentylcarbonyl)-1,4-dioxobutane-2-sulfonate (TC14) displayed enhanced exfoliating efficiency compared to those of the single-and double-chain surfactants, leading to ∼83% MB removal. The findings suggest that highly branched triple-chain surfactants are able to offer more adsorption sites, by expanding the sEGO interlayer gap for MB adsorption, compared to standard single-chain surfactants.
Electrochemical exfoliation of graphite in nanofibrillated kenaf cellulose (NFC)/surfactant mixture for the development of conductive paper

Ardyani T, Mohamed A, Abu Bakar S, Sagisaka M, Umetsu Y, Hafiz Mamat M, et al.

Carbohydr Polym, 2020 Jan 15;228:115376.
PMID: 31635739 DOI: 10.1016/j.carbpol.2019.115376

The effect of incorporating common dodecyl anionic and cationic surfactants such as dodecyltrimethylammonium bromide (DTAB), dodecylethyldimethylammonium bromide (DDAB), and sodium dodecylsulfate (SDS) in nanocomposites of reduced graphene oxide and nanocellulose are described. The stabilization and electrical properties of the nanocomoposites of reduced graphene oxide (RGO) and nanofibrillated kenaf cellulose (NFC) were characterized using four-point probe electrical conductivity measurements. Raman spectroscopy, field emission scanning electron microscopy, and high-resolution transmission electron microscopy were used to investigate dispersion morphology and the quality of RGO inside the NFC matrices. Small-angle neutron scattering (SANS) was used to study the aggregation behavior of the aqueous surfactant systems and RGO dispersions. The cationic surfactant DTAB proved to be the best choice for stabilization of RGO in NFC, giving enhanced electrical conductivity five orders of magnitude higher than the neat NFC. The results highlight the effects of hydrophilic surfactant moieties on the structure, stability and properties of RGO/NFC composites.
Parotid Gland Carcinoma Masquerading as an Aural Polyp

Subha ST, Abu-Bakar S, Prepageran N

Iran J Otorhinolaryngol, 2019 Sep;31(106):315-318.
PMID: 31598500

Introduction: Parotid gland squamous cell carcinoma is an uncommon aggressive neoplasm with poor prognosis. Aural polyps are usually the presenting features of chronic suppurative otitis media, tuberculous otitis media, and adenoma or carcinoma. The malignant aural polyp is very rare. Parotid gland carcinoma masquerading as an aural polyp has rarely been described in the literature.
Case Report: We report a case study of parotid squamous cell carcinoma in a 29-year-old male masquerading as an ear polyp.
Conclusion: Parotid gland primary squamous cell carcinoma is a rapidly advancing neoplasm which carries poor prognosis despite multimodality treatment. Diligent clinical and histopathological evaluation is imperative to discriminate this rare aggressive disease from the metastatic and other primary cancers of the parotid. A high index of suspicion is crucial in refractory aural polyps to arrive at early diagnosis.
Stature estimation in the South-East Asian population: A systematic review

Ismail NA, Abu Bakar SN, Abdullah N, Shafie MS, Mohd Nor F

Malays J Pathol, 2019 Aug;41(2):83-89.
PMID: 31427544

INTRODUCTION: Stature estimation is population dependent, and population-specific regression equations should be generated for accurate anthropological assessments. Nevertheless, stature estimation data was inaccessible and limited in some of the South-East Asian countries. The systematic review was conducted to analyse the regression equations of stature estimations developed in South-East Asian region.
MATERIALS AND METHODS: A systematic literature search was performed through SCOPUS database and Google Scholar from January till March 2018. All published articles which developed stature estimation from different types of bone, methods and type of statures (i.e. living stature, forensic stature and cadaveric stature) were included in this study. Risks of biases were also assessed. Population studies with no regression equations were excluded from the study.
RESULTS: Seven studies that met the inclusion criteria were identified. In the South-East Asia region, regression equations for stature estimation were developed in Thailand and Malaysia. In these studies, bone measurements were done either by radiography, direct bone measurement, or palpation on body surface for anatomical bony prominence. All of these studies used various parts of bones for stature estimation.
CONCLUSION: The most widely used regression equations for stature estimation in South-East Asian population were from the Thailand population. Further research is recommended to develop regression equations for other South-East Asian countries.
Fulltext Isolated sphenoid sinusitis: A big headache

Ishak NL, Subha ST, Abu Bakar S

Malays Fam Physician, 2019;14(1):29-30.
PMID: 31289629

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links