Browse publications by year: 2019

  1. Chia SR, Mak KY, Khaw YJ, Suhaidi N, Chew KW, Show PL
    Bioresour Technol, 2019 Dec;294:122158.
    PMID: 31550634 DOI: 10.1016/j.biortech.2019.122158
    Microalgae are rich in valuable biomolecules and grow on non-arable land with rapid growth rate, which has a host of new possibility as alternative protein sources. In the present study, extraction of proteins from Chlorella vulgaris via an efficient technique, Liquid Triphasic Flotation (LTF) system, was studied. The optimized conditions in LTF system were 70% v/v of t-butanol, 40% w/v of salt solution, 0.5% w/v of biomass, pH 5.54, 1:1 of salt to t-butanol solution, and 10 min of air flotation time to attain 87.23% of protein recovery and 56.72% of separation efficiency. Besides, the study on recycling t-butanol has demonstrated that only one run was sufficient to maintain the performance of system. The efficiency of LTF in extracting protein has performed better than just Three Phase Partitioning (TPP) system. LTF system is hence an effective protein extraction and purification method with minimum operation unit and processing time.
    MeSH terms: Plant Extracts; Biomass; Chlorella vulgaris*; Microalgae*; Recycling
  2. Chai KS, Omar FH, Mat Saad AZ, Wan Sulaiman WA, Halim AS
    Arch Plast Surg, 2019 Sep;46(5):426-432.
    PMID: 31550747 DOI: 10.5999/aps.2018.01487
    BACKGROUND: The mandible is an important structure that is located in the lower third of the face. Large mandibular defects after tumor resection cause loss of its function. This study assessed the outcomes and tumor recurrence after immediate mandibular reconstruction using a free fibula osteocutaneous flap following radical resection of ameloblastoma.

    METHODS: This is a retrospective non-randomized study of outcomes and tumor recurrence of all patients diagnosed with mandibular ameloblastoma from August 1997 until August 2017 (20 years) requiring free fibula osteocutaneous flap reconstruction at a single institution. The patients were identified through an electronic operative database; subsequently, their medical records and photo documentation were retrieved.

    RESULTS: Twenty-seven patients were included in this study. Eighteen patients were male, while nine were female. The majority of the patients (48.1%) were in their third decade of life when they were diagnosed with ameloblastoma. All of them underwent radical resection of the tumor with a surgical margin of 2 cm (hemimandibulectomy in cases with a large tumor) and immediate mandibular reconstruction with a free fibula osteocutaneous flap. Two patients required revision of a vascular anastomosis due to venous thrombosis postoperatively, while one patient developed a flap recipient site infection. The flap success rate was 100%. There was no tumor recurrence during a mean follow-up period of 5.6 years.

    CONCLUSIONS: Mandibular ameloblastoma should be treated with segmental mandibulectomy (with a surgical margin of 2 cm) to reduce the risk of recurrence. Subsequent mandibular and adjacent soft tissue defects should be reconstructed immediately with a free fibula osteocutaneous flap.

    MeSH terms: Ameloblastoma; Documentation; Female; Fibula; Follow-Up Studies; Humans; Male; Mandible; Medical Records; Neoplasm Recurrence, Local; Retrospective Studies; Reconstructive Surgical Procedures; Venous Thrombosis; Free Tissue Flaps; Mandibular Osteotomy; Mandibular Reconstruction; Margins of Excision
  3. Leong KF, Sato R, Oh GGK, Surana U, Pramono ZAD
    Indian J Dermatol, 2019 9 24;64(5):400-403.
    PMID: 31543536 DOI: 10.4103/ijd.IJD_44_18
    Blau syndrome (BS) is a very rare autosomal dominant juvenile inflammatory disorder caused by mutation in nucleotide-binding oligomerization domain containing 2 (NOD2). Usually, dermatitis is the first symptom that appears in the 1st year of life. About 220 BS cases with confirmed NOD2 mutation have been reported. However, the rarity and lack of awareness of the disease, especially in the regions where genetic tests are very limited, often result in late diagnosis and misdiagnosis. Here, we report a de novo BS case from Malaysia, which may be the first report from southeast Asia. PCR and DNA sequencing of peripheral blood mononuclear cells were performed to screen the entire coding region of NOD2 gene. A heterozygous c.1000C>T transition in exon 4, p. R334W, of the NOD2 gene was identified in the patient. This report further reaffirms the ubiquitousness of the disease and recurrency of p. R334W mutation.
    MeSH terms: Adolescent; Arthritis; Dermatitis; Diagnostic Errors; Exons; Genetic Testing; Humans; Leukocytes, Mononuclear; Malaysia; Mutation; Nucleotides; Synovitis; Uveitis; Polymerase Chain Reaction; Sequence Analysis, DNA; Delayed Diagnosis
  4. Kohli S, Sukumar AK, Zhen CT, Yew ASL, Gomez AA
    Dent Res J (Isfahan), 2019;16(5):289-297.
    PMID: 31543934
    BACKGROUND: Even though there are diverse varieties of teaching methods to motivate and educate students, not many are used in dental institutions, where most rely only on traditional lectures. Hence, the objective of this study was to compare traditional lectures with newer teaching methods, specifically the flipped classroom and spaced learning method.

    MATERIALS AND METHODS: In this prospective cohort study Students were randomized to one of the teaching methods, and their short-term (immediately after teaching) and long-term (i.e., 6 months later) knowledge retention was assessed through multiple choice questions, followed by students feedback which was obtained using Trierer Inventar zur Lehrevaluation questionnaire. P ≤ 0.05 was considered statistically significant.

    RESULTS: For short-term learning gains, spaced learning group (165.85) showed highest mean scores, followed by the traditional lecture group (163.70) and flipped classroom group (153.25). P value acquired through the Kruskal-Wallis ANOVA was statistically significant (0.003). For long-term knowledge retention, traditional lecture group has highest mean scores (147.50), followed by spaced learning group (146.90) and flipped classroom group (145.05) with no significant difference (P = 0.657).

    CONCLUSION: Spaced learning methodology was better than the traditional lecture method and the flipped classroom concerning knowledge gains when measured immediately after the application of learning method. For long-term knowledge retention, both the flipped classroom and spaced learning teaching methods were comparable to the traditional lecture method.

  5. Iftikhar M, Shahnawaz, Saleem M, Riaz N, Aziz-Ur-Rehman, Ahmed I, et al.
    Arch Pharm (Weinheim), 2019 Dec;352(12):e1900095.
    PMID: 31544284 DOI: 10.1002/ardp.201900095
    A series of new N-aryl/aralkyl derivatives of 2-methyl-2-{5-(4-chlorophenyl)-1,3,4-oxadiazole-2ylthiol}acetamide were synthesized by successive conversions of 4-chlorobenzoic acid (a) into ethyl 4-chlorobenzoate (1), 4-chlorobenzoylhydrazide (2) and 5-(4-chlorophenyl)-1,3,4-oxadiazole-2-thiol (3), respectively. The required array of compounds (6a-n) was obtained by the reaction of 1,3,4-oxadiazole (3) with various electrophiles (5a-n) in the presence of DMF (N,N-dimethylformamide) and sodium hydroxide at room temperature. The structural determination of these compounds was done by infrared, 1 H-NMR (nuclear magnetic resonance), 13 C-NMR, electron ionization mass spectrometry, and high-resolution electron ionization mass spectrometry analyses. All compounds were evaluated for their α-glucosidase inhibitory potential. Compounds 6a, 6c-e, 6g, and 6i were found to be promising inhibitors of α-glucosidase with IC50 values of 81.72 ± 1.18, 52.73 ± 1.16, 62.62 ± 1.15, 56.34 ± 1.17, 86.35 ± 1.17, 52.63 ± 1.16 µM, respectively. Molecular modeling and ADME (absorption, distribution, metabolism, excretion) predictions supported the findings. The current synthesized library of compounds was achieved by utilizing very common raw materials in such a way that the synthesized compounds may prove to be promising drug leads.
    MeSH terms: alpha-Glucosidases/metabolism*; Computer Simulation; Oxadiazoles/chemical synthesis*; Oxadiazoles/pharmacology; Oxadiazoles/chemistry; Saccharomyces cerevisiae/enzymology; Drug Design*; Molecular Structure; Chemistry Techniques, Synthetic/methods*; Molecular Docking Simulation; Glycoside Hydrolase Inhibitors/chemical synthesis*; Glycoside Hydrolase Inhibitors/pharmacology; Glycoside Hydrolase Inhibitors/chemistry
  6. Fong MY, Lau YL, Jelip J, Ooi CH, Cheong FW
    J Genet, 2019 Sep;98.
    PMID: 31544794
    Plasmodium knowlesi contributes to the majority of human malaria incidences in Malaysia. Its uncontrollable passage among the natural monkey hosts can potentially lead to zoonotic outbreaks. The merozoite of this parasite invades host erythrocytes through interaction between its erythrocyte-binding proteins (EBPs) and their respective receptor on the erythrocytes. The regionII of P. knowlesi EBP, P. knowlesi beta (PkβII) protein is found to be mediating merozoite invasion into monkey erythrocytes by interacting with sialic acid receptors. Hence, the objective of this study was to investigate the genetic diversity, natural selection and haplotype grouping of PkβII of P. knowlesi isolates in Malaysia. Polymerase chain reaction amplifications of PkβII were performed on archived blood samples from Malaysia and 64 PkβII sequences were obtained. Sequence analysis revealed length polymorphism, and its amino acids at critical residues indicate the ability of PkβII to mediate P. knowlesi invasion into monkey erythrocytes. Low genetic diversity (π = 0.007) was observed in the PkβII of Malaysia Borneo compared to Peninsular Malaysia (π = 0.015). The PkβII was found to be under strong purifying selection to retain infectivity in monkeys and it plays a limited role in the zoonotic potential of P. knowlesi. Its haplotypes could be clustered into Peninsular Malaysia and Malaysia Borneo groups, indicating the existence of two distinct P. knowlesi parasites in Malaysia as reported in an earlier study.
    MeSH terms: Animals; Borneo; Erythrocytes/parasitology; Haplotypes; Macaca*; Malaria/parasitology; Malaria/transmission; Malaria/veterinary*; Malaysia; Monkey Diseases/parasitology*; Monkey Diseases/transmission; Phylogeny; Polymorphism, Genetic*; Receptors, Cell Surface; Selection, Genetic; Protozoan Proteins/blood; Protozoan Proteins/genetics*; Plasmodium knowlesi/genetics*; Plasmodium knowlesi/isolation & purification; Sequence Analysis, DNA
  7. Singh R, Singh G, Singh J, Kumar R, Rahman MM, Ramakrishna S
    Proc Inst Mech Eng H, 2019 Nov;233(11):1196-1203.
    PMID: 31545132 DOI: 10.1177/0954411919877979
    In this experimental study, a composite of poly-ether-ketone-ketone by reinforcement of hydroxyapatite and chitosan has been prepared for possible applications as orthopaedic scaffolds. Initially, different weight percentages of hydroxyapatite and chitosan were reinforced in the poly-ether-ketone-ketone matrix and tested for melt flow index in order to check the flowability of different compositions/proportions. Suitable compositions revealed by the melt flow index test were then taken forward for the extrusion of filament required for fused deposition modelling. For thermomechanical investigations, Taguchi-based design of experiments has been used with input variables in the extrusion process as follows: temperature, load applied and different composition/proportions. The specimens in the form of feedstock filament produced by the extrusion process were made to undergo tensile testing. The specimens were also inspected by differential scanning calorimetry and photomicrographs. Finally, the specimen showing the best performance from the thermomechanical viewpoint has been selected to extrude the filament for the fused deposition modelling process.
    MeSH terms: Calorimetry, Differential Scanning; Ether; Ethers; Ketones; Orthopedics; Silicone Elastomers; Temperature; Durapatite; Chitosan
  8. Wen Jun L, Pit Foong C, Abd Hamid R
    Biomed Pharmacother, 2019 Oct;118:109221.
    PMID: 31545225 DOI: 10.1016/j.biopha.2019.109221
    Ardisia crispa Thunb. A. DC. (Primulaceae) has been used extensively as folk-lore medicine in South East Asia including China and Japan to treat various inflammatory related diseases. Ardisia crispa root hexane fraction (ACRH) has been thoroughly studied by our group and it has been shown to exhibit anti-inflammatory, anti-hyperalgesic, anti-arthritic, anti-ulcer, chemoprevention and suppression against inflammation-induced angiogenesis in various animal model. Nevertheless, its effect against human endothelial cells in vitro has not been reported yet. Hence, the aim of the study is to investigate the potential antiangiogenic property of ACRH in human umbilical vein endothelial cells (HUVECs) and zebrafish embryo model. ACRH was separated from the crude ethanolic extract of the plant's root in prior to experimental studies. MTT assay revealed that ACRH exerted a concentration-dependent antiproliferative effect on HUVEC with the IC50 of 2.49 ± 0.04 μg/mL. At higher concentration (10 μg/mL), apoptosis was induced without affecting the cell cycle distribution. Angiogenic properties including migration, invasion and differentiation of HUVECs, evaluated via wound healing, trans-well invasion and tube formation assay respectively, were significantly suppressed by ACRH in a concentration-dependent manner. Noteworthily, significant antiangiogenic effects were observed even at the lowest concentration used (0.1 μg/mL). Expression of proMMP-2, vascular endothelial growth factor (VEGF)-C, VEGF-D, Angiopoietin-2, fibroblast growth factor (FGF)-1, FGF-2, Follistatin, and hepatocyte growth factor (HGF) were significantly reduced in various degrees by ACRH. The ISV formation in zebrafish embryo was significantly suppressed by ACRH at the concentration of 5 μg/mL. These findings revealed the potential of ACRH as antiangiogenic agent by suppressing multiple proangiogenic proteins. Thus, it can be further verified via the transcription of these proteins from their respective DNA, in elucidating their exact pathways.
    MeSH terms: Animals; Cell Differentiation; Cell Movement; Embryo, Nonmammalian/metabolism*; Hexanes/chemistry*; Humans; Neovascularization, Pathologic/drug therapy*; Neovascularization, Pathologic/pathology; Zebrafish/embryology*; Apoptosis; Plant Roots/chemistry*; Matrix Metalloproteinases/metabolism; Models, Animal; Ardisia/chemistry*; Cell Proliferation; Cell Cycle Checkpoints; Human Umbilical Vein Endothelial Cells/metabolism*; Human Umbilical Vein Endothelial Cells/pathology
  9. Chen RS, Mohd Ruf MFH, Shahdan D, Ahmad S
    PLoS One, 2019;14(9):e0222662.
    PMID: 31545820 DOI: 10.1371/journal.pone.0222662
    Thermoplastic natural rubber (TPNR) was compounded with graphene nanoplatelets (GNP) via ultrasonication and melt blending. The effects of ultrasonication period (1-4 hours) and GNP weight fraction (0.5, 1.0, 1.5 and 2.0 wt.%) on the mechanical, thermal and conductivity properties were investigated. Results showed that the 3 hours of ultrasonic treatment on LNR/GNP gave the greatest improvement in tensile strength of 25.8% (TPNR/GNP nanocomposites) as compared to those without ultrasonication. The TPNR nanocomposites containing 1.5 wt.% GNP exhibited the highest strength (16 MPa for tensile, 14 MPa for flexural and 11 kJm-2 for impact) and modulus (556 MPa and 869 MPa for tensile and flexural, respectively). The incorporation of GNP had enhanced the thermal stability. It can be concluded that the GNP had imparted the thermally and electrically conductive nature to the TPNR blend.
    MeSH terms: Electric Conductivity; Graphite; Peptide Fragments; Rubber; Tensile Strength; Ultrasonics; Nanocomposites
  10. Wong JHD, Ng KH, Sarasanandarajah S
    Phys Med, 2019 Oct;66:21-28.
    PMID: 31546154 DOI: 10.1016/j.ejmp.2019.09.079
    The increased use of medical imaging and radiation therapies has resulted in a high demand for medical physicists. Although medical physics programmes are well established in advanced countries, the same cannot be said for many low- and medium-income countries. In some countries, there may be huge variations in the graduates' skill and quality, which pose a problem in ensuring patient safety, providing quality assurance in treatments, optimisation of protocols and standardisation of quality. It also makes any yet-to-be-established regional peer recognition efforts problematic. In order to understand the depth of this problem, a survey was carried out as part of the home-based assignment under the RAS 6088 IAEA programme. A large diversity in terms of course content, duration, clinical training and student profile could be observed across the Asia-Oceania universities surveyed. Out of 25 programmes, only six received recognition from professional bodies, and they were mostly in Australia and New Zealand. Hence, to ensure quality education, a regional curriculum model needs to be developed to harmonise standards. And there is still a long way to go towards standardizing medical physics education and clinical training in the region.
    MeSH terms: Asia; Demography; Education, Medical/statistics & numerical data*; Education, Medical, Graduate/statistics & numerical data*; Humans; Surveys and Questionnaires*; Students, Medical/statistics & numerical data; Oceania
  11. Rahim F, Tariq S, Taha M, Ullah H, Zaman K, Uddin I, et al.
    Bioorg Chem, 2019 11;92:103284.
    PMID: 31546207 DOI: 10.1016/j.bioorg.2019.103284
    New triazinoindole bearing thiazole/oxazole analogues (1-21) were synthesized and characterized through spectroscopic techniques such as HREI-MS, 1H and 13C NMR. The configuration of compound 2i and 2k was confirmed through NOESY. All analogues were evaluated against α-amylase inhibitory potential. Among the synthesized analogues, compound 1h, 1i, 1j, 2a and 2f having IC50 values 1.80 ± 0.20, 1.90 ± 0.30, 1.2 ± 0.30, 1.2 ± 0.01 and 1.30 ± 0.20 μM respectively, showed excellent α-amylase inhibitory potential when compared with acarbose as standard (IC50 = 0.91 ± 0.20 µM). All other analogues showed good to moderate inhibitory potential. Structural activity relationship (SAR) has been established and binding interactions were confirmed through docking studies.
    MeSH terms: alpha-Amylases/antagonists & inhibitors*; alpha-Amylases/metabolism; Dose-Response Relationship, Drug; Humans; Oxazoles/pharmacology*; Oxazoles/chemistry; Structure-Activity Relationship; Thiazoles/pharmacology*; Thiazoles/chemistry; Triazines/chemical synthesis; Triazines/pharmacology*; Triazines/chemistry; Molecular Structure; Molecular Docking Simulation*; Glycoside Hydrolase Inhibitors/chemical synthesis; Glycoside Hydrolase Inhibitors/pharmacology*; Glycoside Hydrolase Inhibitors/chemistry
  12. Wu D, Hii LY, Shaw SWS
    Taiwan J Obstet Gynecol, 2019 Sep;58(5):684-687.
    PMID: 31542093 DOI: 10.1016/j.tjog.2019.07.018
    OBJECTIVE: We report a rare case of heterotopic pregnancy and high-order pregnancy occurring simultaneously following the use of the assisted reproductive technique (ART).

    CASE REPORT: A 29-year-old woman, Gravida 2 Para 1, became pregnant after receiving intrauterine insemination (IUI). She came to our emergency room due to diffuse low abdominal pain at seven weeks of gestational age. Transabdominal sonography (TAS) revealed a quadruplet intrauterine pregnancy with an enlarged left adnexa and intrapelvic fluid accumulation. Simultaneous occurrence of high-order pregnancy and left tubal pregnancy with internal hemorrhage was suspected. The patient received an emergent laparoscopic resection of the affected Fallopian tube and recovered well for the remaining hospitalization course. Afterwards, she received fetal reduction procedure and eventually gave birth to twin babies.

    CONCLUSION: Gynecologist should increase the awareness of heterotopic pregnancy in patients receiving ART. On the other hand, reproductive endocrinologist should reduce the risk of high-order pregnancy without compromising pregnancy rate.

    MeSH terms: Adult; Female; Humans; Insemination, Artificial/adverse effects*; Pregnancy; Pregnancy, Tubal/etiology*; Pregnancy, Tubal/surgery; Twins; Pregnancy Reduction, Multifetal; Live Birth; Pregnancy, Quadruplet*; Pregnancy, Heterotopic/etiology*; Pregnancy, Heterotopic/surgery
  13. Chieng N, Teo X, Cheah MH, Choo ML, Chung J, Hew TK, et al.
    J Pharm Sci, 2019 12;108(12):3848-3858.
    PMID: 31542436 DOI: 10.1016/j.xphs.2019.09.013
    The study aims to characterize the structural relaxation times of quench-cooled co-amorphous systems using Kohlrausch-Williams-Watts (KWW) and to correlate the relaxation data with the onset of crystallization. Comparison was also made between the relaxation times obtained by KWW and the width of glass transition temperature (ΔTg) methods (simple and quick). Differential scanning calorimetry, Fourier-transformed infrared spectroscopy, and polarized light microscopy were used to characterize the systems. Results showed that co-amorphous systems yielded a single Tg and ΔCp, suggesting the binary mixtures exist as a single amorphous phase. A narrow step change at Tg indicates the systems were fragile glasses. In co-amorphous nap-indo and para-indo, experimental Tgs were in good agreement with the predicted Tg. However, the Tg of co-amorphous nap-cim and indo-cim were 20°C higher than the predicted Tg, possibly due to stronger molecular interactions. Structural relaxation times below the experimental Tg were successfully characterized using the KWW and ΔTg methods. The comparison plot showed that KWW data are directly proportional to the ½ power of ΔTg data, after adjusting for a small offset. A moderate positive correlation was observed between the onset of crystallization and the KWW data. Structural relaxation times may be useful predictor of physical stability of co-amorphous systems.
    MeSH terms: Calorimetry, Differential Scanning/methods; Chemistry, Pharmaceutical/methods; Crystallization/methods; Glass/chemistry*; Thermodynamics; Spectroscopy, Fourier Transform Infrared/methods; Transition Temperature; Phase Transition; Molecular Dynamics Simulation
  14. Filho WL, Balogun AL, Olayide OE, Azeiteiro UM, Ayal DY, Muñoz PDC, et al.
    Sci Total Environ, 2019 Nov 20;692:1175-1190.
    PMID: 31539949 DOI: 10.1016/j.scitotenv.2019.07.227
    Many cities across the world are facing many problems climate change poses to their populations, communities and infrastructure. These vary from increased exposures to floods, to discomfort due to urban heat, depending on their geographical locations and settings. However, even though some cities have a greater ability to cope with climate change challenges, many struggle to do so, particularly in cities in developing countries. In addition, there is a shortage of international studies which examine the links between climate change adaptation and cities, and which at the same time draw some successful examples of good practice, which may assist future efforts. This paper is an attempt to address this information need. The aim of this paper is to analyse the extent to which cities in a sample of developing countries are attempting to pursue climate change adaptation and the problems which hinder this process. Its goal is to showcase examples of initiatives and good practice in transformative adaptation, which may be replicable elsewhere. To this purpose, the paper describes some trends related to climate change in a set of cities in developing countries across different continents, including one of the smallest capital cities (Georgetown, Guyana) and Shanghai, one the world's most populous cities. In particular, it analyses their degree of vulnerability, how they manage to cope with climate change impacts, and the policies being implemented to aid adaptation. It also suggests the use of transformative approaches which may be adopted, in order to assist them in their efforts towards investments in low-carbon and climate-resilient infrastructure, thereby maximizing investments in urban areas and trying to address their related poverty issues. This paper addresses a gap in the international literature on the problems many cities in developing countries face, in trying to adapt to a changing climate.
    MeSH terms: Acclimatization; Carbon; China; Cities; Developing Countries; Goals; Guyana; Hot Temperature; Investments; Poverty; Floods; Climate Change; Policy
  15. MohdIsa W, Hunt A, HosseinNia SH
    Sensors (Basel), 2019 Sep 14;19(18).
    PMID: 31540032 DOI: 10.3390/s19183967
    Ionic polymer-metal composites (IPMC) are smart material transducers that bend in response to low-voltage stimuli and generate voltage in response to bending. IPMCs are mechanically compliant, simple in construction, and easy to cut into desired shape. This allows the designing of novel sensing and actuation systems, e.g., for soft and bio-inspired robotics. IPMC sensing can be implemented in multiple ways, resulting in significantly different sensing characteristics. This paper will review the methods and research efforts to use IPMCs as deformation sensors. We will address efforts to model the IPMC sensing phenomenon, and implementation and characteristics of different IPMC sensing methods. Proposed sensing methods are divided into active sensing, passive sensing, and self-sensing actuation (SSA), whereas the active sensing methods measure one of IPMC-generated voltage, charge, or current; passive methods measure variations in IPMC impedances, or use it in capacitive sensor element circuit, and SSA methods implement simultaneous sensing and actuation on the same IPMC sample. Frequency ranges for reliable sensing vary among the methods, and no single method has been demonstrated to be effective for sensing in the full spectrum of IPMC actuation capabilities, i.e., from DC to ∼100 Hz. However, this limitation can be overcome by combining several sensing methods.
    MeSH terms: Ions; Metals; Polymers; Robotics; Transducers; Electric Impedance
  16. Napi MLM, Sultan SM, Ismail R, How KW, Ahmad MK
    Materials (Basel), 2019 Sep 15;12(18).
    PMID: 31540160 DOI: 10.3390/ma12182985
    Electrochemical biosensors have shown great potential in the medical diagnosis field. The performance of electrochemical biosensors depends on the sensing materials used. ZnO nanostructures play important roles as the active sites where biological events occur, subsequently defining the sensitivity and stability of the device. ZnO nanostructures have been synthesized into four different dimensional formations, which are zero dimensional (nanoparticles and quantum dots), one dimensional (nanorods, nanotubes, nanofibers, and nanowires), two dimensional (nanosheets, nanoflakes, nanodiscs, and nanowalls) and three dimensional (hollow spheres and nanoflowers). The zero-dimensional nanostructures could be utilized for creating more active sites with a larger surface area. Meanwhile, one-dimensional nanostructures provide a direct and stable pathway for rapid electron transport. Two-dimensional nanostructures possess a unique polar surface for enhancing the immobilization process. Finally, three-dimensional nanostructures create extra surface area because of their geometric volume. The sensing performance of each of these morphologies toward the bio-analyte level makes ZnO nanostructures a suitable candidate to be applied as active sites in electrochemical biosensors for medical diagnostic purposes. This review highlights recent advances in various dimensions of ZnO nanostructures towards electrochemical biosensor applications.
    MeSH terms: Electron Transport; Zinc Oxide; Biosensing Techniques; Catalytic Domain; Nanotubes; Quantum Dots; Nanostructures; Nanoparticles; Nanowires; Nanofibers
  17. Masdor NA, Altintas Z, Shukor MY, Tothill IE
    Sci Rep, 2019 09 20;9(1):13642.
    PMID: 31541137 DOI: 10.1038/s41598-019-49672-2
    In this work, a subtractive inhibition assay (SIA) based on surface plasmon resonance (SPR) for the rapid detection of Campylobacter jejuni was developed. For this, rabbit polyclonal antibody with specificity to C. jejuni was first mixed with C. jejuni cells and unbound antibody was subsequently separated using a sequential process of centrifugation and then detected using an immobilized goat anti-rabbit IgG polyclonal antibody on the SPR sensor chip. This SIA-SPR method showed excellent sensitivity for C. jejuni with a limit of detection (LOD) of 131 ± 4 CFU mL-1 and a 95% confidence interval from 122 to 140 CFU mL-1. The method has also high specificity. The developed method showed low cross-reactivity to bacterial pathogens such as Salmonella enterica serovar Typhimurium (7.8%), Listeria monocytogenes (3.88%) and Escherichia coli (1.56%). The SIA-SPR method together with the culturing (plating) method was able to detect C. jejuni in the real chicken sample at less than 500 CFU mL-1, the minimum infectious dose for C. jejuni while a commercial ELISA kit was unable to detect the bacterium. Since the currently available detection tools rely on culturing methods, which take more than 48 hours to detect the bacterium, the developed method in this work has the potential to be a rapid and sensitive detection method for C. jejuni.
    MeSH terms: Animals; Antibodies, Bacterial/metabolism*; Campylobacter Infections/diagnosis; Campylobacter Infections/immunology; Campylobacter Infections/veterinary*; Chickens; Immunoglobulin G/metabolism; Poultry Diseases/immunology; Poultry Diseases/microbiology*; Rabbits; Sensitivity and Specificity; Campylobacter jejuni/immunology; Campylobacter jejuni/isolation & purification*; Surface Plasmon Resonance; Limit of Detection
  18. Karupaiah T, Chuah KA, Chinna K, Pressman P, Clemens RA, Hayes AW, et al.
    Sci Rep, 2019 09 20;9(1):13666.
    PMID: 31541144 DOI: 10.1038/s41598-019-49911-6
    We conducted this cross-sectional population study with a healthy multi-ethnic urban population (n = 577) in Malaysia, combining nutritional assessments with cardiometabolic biomarkers defined by lipid, atherogenic lipoproteins, inflammation and insulin resistance. We found diametrically opposing associations of carbohydrate (246·6 ± 57·7 g, 54·3 ± 6·5%-TEI) and fat (total = 64·5 ± 19·8 g, 31·6 ± 5·5%-TEI; saturated fat = 14·1 ± 2·7%-TEI) intakes as regards waist circumference, HDL-C, blood pressure, glucose, insulin and HOMA2-IR as well as the large-LDL and large-HDL lipoprotein particles. Diets were then differentiated into either low fat (LF, <30% TEI or <50 g) or high fat (HF, >35% TEI or >70 g) and low carbohydrate (LC, <210 g) or high carbohydrate (HC, >285 g) which yielded LFLC, LFHC, HFLC and HFHC groupings. Cardiometabolic biomarkers were not significantly different (P > 0.05) between LFLC and HFLC groups. LFLC had significantly higher large-LDL particle concentrations compared to HFHC. HOMA-IR2 was significantly higher with HFHC (1·91 ± 1·85, P 1.7 in the HFHC group was 2.43 (95% CI: 1·03, 5·72) times more compared to LFLC while odds of having large-LDL <450 nmol/L in the HFHC group was 1.91 (95% CI: 1·06, 3·44) more compared to latter group. Our data suggests that a HFHC dietary combination in Malaysian adults is associated with significant impact on lipoprotein particles and insulin resistance.
    MeSH terms: Adult; Cross-Sectional Studies; Dietary Carbohydrates/administration & dosage*; Dietary Fats/administration & dosage*; Female; Humans; Insulin Resistance*; Lipoproteins/blood*; Malaysia/ethnology; Male; Middle Aged; Biomarkers/blood*; Nutrition Assessment; Waist Circumference
  19. Leonhard SE, Mandarakas MR, Gondim FAA, Bateman K, Ferreira MLB, Cornblath DR, et al.
    Nat Rev Neurol, 2019 Nov;15(11):671-683.
    PMID: 31541214 DOI: 10.1038/s41582-019-0250-9
    Guillain-Barré syndrome (GBS) is a rare, but potentially fatal, immune-mediated disease of the peripheral nerves and nerve roots that is usually triggered by infections. The incidence of GBS can therefore increase during outbreaks of infectious diseases, as was seen during the Zika virus epidemics in 2013 in French Polynesia and 2015 in Latin America. Diagnosis and management of GBS can be complicated as its clinical presentation and disease course are heterogeneous, and no international clinical guidelines are currently available. To support clinicians, especially in the context of an outbreak, we have developed a globally applicable guideline for the diagnosis and management of GBS. The guideline is based on current literature and expert consensus, and has a ten-step structure to facilitate its use in clinical practice. We first provide an introduction to the diagnostic criteria, clinical variants and differential diagnoses of GBS. The ten steps then cover early recognition and diagnosis of GBS, admission to the intensive care unit, treatment indication and selection, monitoring and treatment of disease progression, prediction of clinical course and outcome, and management of complications and sequelae.
    MeSH terms: Zika Virus Infection/diagnosis; Zika Virus Infection/epidemiology; Zika Virus Infection/therapy; Humans; Genetic Variation/genetics; Disease Management*; Guillain-Barre Syndrome/diagnosis*; Guillain-Barre Syndrome/epidemiology; Guillain-Barre Syndrome/therapy*
  20. Wang R, Hu X, Lü A, Liu R, Sun J, Sung YY, et al.
    Fish Shellfish Immunol, 2019 Nov;94:510-516.
    PMID: 31541778 DOI: 10.1016/j.fsi.2019.09.039
    Skin plays an important role in the innate immune responses of fish, particularly towards bacterial infection. To understand the molecular mechanism of mucosal immunity of fish during bacterial challenge, a de novo transcriptome assembly of crucian carp Carassius auratus skin upon Aeromonas hydrophila infection was performed, the latter with Illumina Hiseq 2000 platform. A total of 118111 unigenes were generated and of these, 9693 and 8580 genes were differentially expressed at 6 and 12 h post-infection, respectively. The validity of the transcriptome results of eleven representative genes was verified by quantitative real-time PCR (qRT-PCR) analysis. A comparison with the transcriptome profiling of zebrafish skin to A. hydrophila with regards to the mucosal immune responses revealed similarities in the complement system, chemokines, heat shock proteins and the acute-phase response. GO and KEGG enrichment pathway analyses displayed the significant immune responses included TLR, MAPK, JAK-STAT, phagosome and three infection-related pathways (ie., Salmonella, Vibrio cholerae and pathogenic Escherichia coli) in skin. To our knowledge, this study is the first to describe the transcriptome analysis of C. auratus skin during A. hydrophila infection. The outcome of this study contributed to the understanding of the mucosal defense mechanisms in cyprinid species.
    MeSH terms: Animals; Fish Diseases/immunology*; Goldfish/genetics*; Goldfish/immunology*; Immunity, Innate/genetics*; Skin/metabolism*; Gram-Negative Bacterial Infections/immunology; Gram-Negative Bacterial Infections/veterinary; Aeromonas hydrophila/physiology; Gene Expression Profiling/veterinary
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