Browse publications by year: 2019

  1. Ismail I, Hwang YH, Joo ST
    Food Sci Anim Resour, 2019 Feb;39(1):45-53.
    PMID: 30882073 DOI: 10.5851/kosfa.2019.e2
    This study observed the effects of the double combination of temperatures-times (2 temperatures: 2 times combination, 2T2T) in sous vide cooking method on the physicochemical properties and collagen solubility (CS) of semitendinosus muscle from cattle and goat as a comparison to common sous vide treatment (1 temperature: 1 time combination, 1T1T). The new invention of sous vide cooking method (2T2T) cooked at the first temperature at 45°C for 3 h, and the second temperature at 60°C, 65°C, and 70°C for 3 h, and labeled as N45-60, N45-65, and N45-70, respectively. While, common sous vide treatment (1T1T) were cooked directly for 6 h at 60°C (T60), 65°C (T65), and 70°C (T70). Results revealed that cooking with 2T2T treatment improved the water-holding capacity and reduced the cooking loss of both beef and goat meat. The L* values have no apparent changes between treatment in beef and goat meat, while a* values of N45-60 treated goat presented markedly higher values than other treatments but an only slight increase in beef at the same treatment (p>0.05). Again, 2T2T treatment tended to decrease mean shear force (SF) values for beef and goat meat with the lowest SF values recorded at N45-60, and the CS no or less influenced this value. Therefore, the application of innovative sous vides cooking method (2T2T) presented comparable values in the treated beef and goat meat as compared to common sous vide method (1T1T).
  2. Seri Masran SNA, Ab Majid AH
    J Med Entomol, 2019 06 27;56(4):942-952.
    PMID: 30882146 DOI: 10.1093/jme/tjz024
    The surge in tropical bed bug Cimex hemipterus (Fabricius) (Hemiptera: Cimicidae) infestations has led to an increase in genomic studies. In this study, the population genetics and breeding patterns of 22 Malaysian populations were analyzed, including genetic differentiation and genetic distance. For seven microsatellite loci, the number of alleles varied from 6 to 14. The allelels per loci contrasted sharply between the overall population and within the populations. The average observed and expected heterozygosity was 0.280 and 0.828 for the overall population and 0.281 and 0.657 among the populations, respectively. Based on polymorphic information criteria, the markers with a value >0.5 were highly polymorphic. In the Hardy-Weinberg equilibrium, the loci of Ch 09ttn, Ch 01dn, and Ch 13dn of the overall population showed signs of a null allele. The stutter peaks caused no scoring errors; large allele dropouts were not detected for any loci; and a correlation imbalance was not indicated. The genetic differentiation among populations was moderate, with a coefficient of genetic differentiation (FST) of 0.144. The bed bug populations showed strong inbreeding, with highly positive coefficients of inbreeding (FIS). The molecular variation attributed to inbreeding was 83% within the populations, compared with 17% among the populations. The admixture individuals in STRUCTURE and neighbor-joining phylogenetic trees also indicated weak genetic structure in the geographical populations, suggesting moderate gene flows between populations. Thus, moderately active dispersion and human-mediated transport shaped the genetic structure of C. hemipterus populations in Malaysia.
    MeSH terms: Animals; Bedbugs/genetics*; Malaysia; Genetic Variation*; Microsatellite Repeats; Gene Flow; Phylogeography; Animal Distribution
  3. Liao JF, Hsu CC, Chou GT, Hsu JS, Liong MT, Tsai YC
    Benef Microbes, 2019 Apr 19;10(4):425-436.
    PMID: 30882243 DOI: 10.3920/BM2018.0077
    Maternal separation (MS) has been developed as a model for inducing stress and depression in studies using rodents. The concept of the gut-brain axis suggests that gut health is essential for brain health. Here, we present the effects of administration of a probiotic, Lactobacillus paracasei PS23 (PS23), to MS mice against psychological traits including anxiety and depression. The administration of live and heat-killed PS23 cells showed positive behavioural effects on MS animals, where exploratory tendencies and mobility were increased in behavioural tests, indicating reduced anxiety and depression compared to the negative control mice (P<0.05). Mice administered with both live and heat-killed PS23 cells also showed lower serum corticosterone levels accompanied by higher serum anti-inflammatory interleukin 10 (IL-10) levels, compared to MS separated mice (P<0.05), indicating a stress-elicited response affiliated with increased immunomodulatory properties. Assessment of neurotransmitters in the brain hippocampal region revealed that PS23 affected the concentrations of dopaminergic metabolites differently than the control, suggesting that PS23 may have improved MS-induced stress levels via neurotransmitter pathways, such as dopamine or other mechanisms not addressed in the current study. Our study illustrates the potential of a probiotic in reversing abnormalities induced by early life stress and could be an alternative for brain health along the gut-brain axis.
    MeSH terms: Behavior Rating Scale; Animals; Anxiety; Brain; Corticosterone; Depression; Depressive Disorder; Dopamine; Hot Temperature; Hippocampus; Maternal Deprivation; Rodentia; Stress, Psychological; Interleukin-10; Neurotransmitter Agents; Probiotics; Mice; Lactobacillus paracasei
  4. Chong HX, Yusoff NAA, Hor YY, Lew LC, Jaafar MH, Choi SB, et al.
    Benef Microbes, 2019 Apr 19;10(4):355-373.
    PMID: 30882244 DOI: 10.3920/BM2018.0135
    Probiotics have been reported to exert beneficial effects along the gut-brain axis. This randomised, double-blind and placebo-controlled human study aimed to evaluate such properties of Lactobacillus plantarum DR7 and its accompanying mechanisms in stressed adults. One hundred and eleven (n=111; DR7 n=56, placebo n=55) stressed adults were recruited based on moderate stress levels using the PSS-10 questionnaire. The consumption of DR7 (1×109 cfu/day) for 12 weeks reduced symptoms of stress (P=0.024), anxiety (P=0.001), and total psychological scores (P=0.022) as early as 8 weeks among stressed adults compared to the placebo group as assessed by the DASS-42 questionnaire. Plasma cortisol level was reduced among DR7 subjects as compared to the placebo, accompanied by reduced plasma pro-inflammatory cytokines, such as interferon-γ and transforming growth factor-α and increased plasma anti-inflammatory cytokines, such as interleukin 10 (P<0.05). DR7 better improved cognitive and memory functions in normal adults (>30 years old), such as basic attention, emotional cognition, and associate learning (P<0.05), as compared to the placebo and young adults (<30 years old). The administration of DR7 enhanced the serotonin pathway, as observed by lowered expressions of plasma dopamine β-hydroxylase (DBH), tyrosine hydroxylase (TH), indoleamine 2,3-dioxygenase and tryptophan 2,3-dioxygenase accompanied by increased expressions of tryptophan hydroxylase-2 and 5-hydroxytryptamine receptor-6, while stabilising the dopamine pathway as observed via stabilised expressions of TH and DBH over 12 weeks as compared to the placebo (P<0.05). Our results indicated that DR7 fulfil the requirement of a probiotic strain as per recommendation of FAO/WHO and could be applicable as a natural strategy to improve psychological functions, cognitive health and memory in stressed adults.
  5. Abu Hassan MR, Aziz N, Ismail N, Shafie Z, Mayala B, Donohue RE, et al.
    PLoS Negl Trop Dis, 2019 03;13(3):e0007243.
    PMID: 30883550 DOI: 10.1371/journal.pntd.0007243
    BACKGROUND: Melioidosis, a fatal infectious disease caused by Burkholderia pseudomallei, is increasingly diagnosed in tropical regions. However, data on risk factors and the geographic epidemiology of the disease are still limited. Previous studies have also largely been based on the analysis of case series data. Here, we undertook a more definitive hospital-based matched case-control study coupled with spatial analysis to identify demographic, socioeconomic and landscape risk factors for bacteremic melioidosis in the Kedah region of northern Malaysia.

    METHODOLOGY/PRINCIPAL FINDINGS: We obtained patient demographic and residential information and clinical presentation and medical history data from 254 confirmed melioidosis cases and 384 matched controls attending Hospital Sultanah Bahiyah (HSB), the main tertiary hospital of Alor Setar, the capital city of Kedah, during the period between 2005 and 2011. Crude and adjusted odds ratios employing conditional logistic regression analysis were used to assess if melioidosis in this region is related to risk factors connected with socio-demographics, various behavioural characteristics, and co-occurring diseases. Spatial clusters of cases were determined using a continuous Poisson model as deployed in SaTScan. A land cover map in conjunction with mapped case data was used to determine disease-land type associations using the Fisher's exact test deploying simulated p-values. Crude and adjusted odds ratios indicate that melioidosis in this region is related to gender (males), race, occupation (farming) and co-occurring chronic diseases, particularly diabetes. Spatial analyses of disease incidence, however, showed that disease risk and geographic clustering of cases are related strongly to land cover types, with risk of disease increasing non-linearly with the degree of human modification of the natural ecosystem.

    CONCLUSIONS/SIGNIFICANCE: These findings indicate that melioidosis represents a complex socio-ecological public health problem in Kedah, and that its control requires an understanding and modification of the coupled human and natural variables that govern disease transmission in endemic communities.

    MeSH terms: Agriculture; Chronic Disease; Diabetes Mellitus; Ecology; Humans; Malaysia; Male; Melioidosis; Occupations; Public Health; Risk Factors; Incidence; Logistic Models; Odds Ratio; Case-Control Studies; Bacteremia; Burkholderia pseudomallei; Ecosystem; Spatial Analysis; Tertiary Care Centers
  6. Decurcio DA, Lim E, Chaves GS, Nagendrababu V, Estrela C, Rossi-Fedele G
    Int Endod J, 2019 Aug;52(8):1153-1161.
    PMID: 30883828 DOI: 10.1111/iej.13116
    AIM: To compare the educational outcomes using artificial teeth versus extracted teeth for pre-clinical endodontic training.

    DATA SOURCES: Literature searches of PubMed, Scopus, Cochrane Library, Trip Database, Web of Science and Open Grey databases were conducted from their inception until November 2018 with no language restriction. Hand searching of most likely relevant journals was performed. The review followed the PRISMA guidelines.

    STUDY ELIGIBILITY CRITERIA, PARTICIPANTS AND INTERVENTIONS: Studies that compared pre-clinical endodontic training using extracted teeth and artificial teeth were included.

    STUDY APPRAISAL AND SYNTHESIS METHODS: The quality of included studies was appraised by Joanna Briggs Institute Critical Appraisal tools. The findings were tabulated and summarized according to their outcomes with distinct narrative syntheses.

    RESULTS: Five studies were included. The component studies included 359 operators in total, mainly consisting of undergraduate students (97%, n = 349) and 10 endodontists (3%). Forty-seven per cent (n = 170) operated on artificial teeth only, whilst 19% (n = 67) worked primarily on extracted teeth, with the final treatment outcome being evaluated by independent observers using objective criteria. Operators in two studies (34%, n = 122) used both artificial teeth and ET and compared their experiences in surveys. Regarding technical outcomes, no significant differences between training with artificial teeth and extracted teeth were found, but the performance tended to be better in artificial teeth than extracted teeth. Operators trained solely on artificial teeth appeared to be adequately educated for subsequent root canal treatment (RCT) in the clinical setting.

    LIMITATIONS: Due to the scarcity of research on the topic overall, and the methodological variation between the studies, it was not possible to perform a quantitative analysis (meta-analysis).

    CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS: Based on the available evidence, the use of artificial teeth for pre-clinical endodontic training achieved similar educational outcomes compared to extracted teeth. However, the experiences reported by the operators diverged. Further studies assessing other artificial teeth available in the market testing other RCT procedures are necessary.

    MeSH terms: Humans; Root Canal Therapy*
  7. Muhammed A, Khuan L, Shariff-Ghazali S, Said SM, Hassan M
    Midwifery, 2019 Jun;73:62-68.
    PMID: 30884373 DOI: 10.1016/j.midw.2019.03.004
    OBJECTIVE: Planned home birth may increase women's access to skilled midwives in all settings. Using theory to understand and predict midwives' intention regarding planned home birth services is rare. Therefore, using the theory of planned behaviour, we determined the factors associated with midwives' intention to provide planned home birth services to low-risk women.

    DESIGN: This cross-sectional study adopted a quantitative approach and a survey. Stratified random sampling was used to recruit 226 midwives in Sokoto, Nigeria. Data-including descriptive statistic and multiple linear regression analyses-were analysed using SPSS 23 and significant was set at 0.05.

    SETTING: Ten public health facilities in Sokoto, northwestern Nigeria.

    PARTICIPANTS: Among all 460 midwives (women aged 20-60 years), working in the maternity wards of health facilities in Sokoto, a sample of 226 midwives was calculated using a power of 0.80 and a 95% confidence interval.

    FINDINGS: The multiple linear regression analyses confirmed that the major factors associated with midwives' intention to provide planned home birth services were midwives' attitude towards planned home birth (p < .001) and midwives' previous experience with planned home birth practice (p = .008).

    CONCLUSIONS AND IMPLICATIONS: The theory of planned behaviour is a useful framework for identifying factors that affect midwives' intention to provide planned home birth services. While future research may employ a qualitative approach to explore other factors, planned home birth education campaigns should target information that enhances positive attitude and encourages midwives to provide planned home birth services.

    MeSH terms: Adult; Attitude of Health Personnel; Cross-Sectional Studies; Female; Health Planning/methods; Health Planning/standards; Health Services Accessibility/standards; Home Childbirth/nursing*; Home Childbirth/psychology; Humans; Middle Aged; Nigeria; Nurse Midwives/psychology*; Pregnancy; Surveys and Questionnaires; Intention*; Qualitative Research
  8. Fong CY, Hong SY, Ong LC, Lim WK, Lua PL
    Epilepsy Behav, 2019 May;94:52-58.
    PMID: 30884408 DOI: 10.1016/j.yebeh.2019.02.008
    BACKGROUND: An information technology (IT)-based epilepsy educational program, the Interactive Animated Epilepsy Education Programme (IAEEP), can potentially help improve awareness, knowledge, and attitude (AKA) of parents of children with epilepsy (CWE) enabling CWE to lead a normal life. Our study aimed to assess the following: i) baseline level of epilepsy AKA of Malaysian parents of CWE and explore potential characteristics associated with low levels of AKA; ii) effectiveness of the IAEEP in improving parental AKA, and whether these effects remained stable over time; and iii) effects of the IAEEP on parental mental state and perception of their child's quality of life.

    METHODS: This prospective study includes parents of CWE aged 8-18 years old with no comorbidities. Epilepsy education was delivered using the IAEEP. Parents completed an AKA questionnaire before (time point 1 [TP1]), immediately after (TP2), and 4-6 months (TP3) after the provision of IAEEP. Parent proxy report of Health-Related Quality of Life Measurement for Children with Epilepsy (CHEQOL)-25 questionnaire and Depression, Anxiety, and Stress Scale (DASS)-21 questionnaire was completed at TP1 and TP3.

    RESULTS: A total of 78 parents participated in the study. At baseline (TP1), parental responses were rated as "moderate" for awareness domain, "high" for knowledge domain, "very positive" for attitude domain, and "good" for total AKA score domain. No epilepsy or parental characteristics were associated with the low baseline parental AKA levels. After IAEEP intervention, there was a significant increase in all AKA subdomain scores. Post-IAEEP, the AKA of parents were rated as "very high" for awareness domain, "very high" for knowledge domain, "very positive" for attitude domain, and "excellent" for total AKA domain at both TP2 and TP3. Parent proxy CHEQOL-25 report showed significant increments in interpersonal/social and secrecy scale scores between TP1 and TP3. There were no significant differences in the DASS-21 scores between TP1 and TP3.

    CONCLUSION: The IAEEP is an effective epilepsy educational tool to increase the levels of AKA among parents of CWE. Following the use of the IAEEP, parents of CWE also reported an improvement of their child's quality of life in the interpersonal/social and epilepsy secrecy CHEQOL-25 domains. There was no impact on parental mental health following exposure to the IAEEP.

  9. Saeed, Sana, Ong, Hong Choon
    MyJurnal
    Support vector machine (SVM) is one of the most popular algorithms in machine learning
    and data mining. However, its reduced efficiency is usually observed for imbalanced
    datasets. To improve the performance of SVM for binary imbalanced datasets, a new scheme
    based on oversampling and the hybrid algorithm were introduced. Besides the use of a
    single kernel function, SVM was applied with multiple kernel learning (MKL). A weighted
    linear combination was defined based on the linear kernel function, radial basis function
    (RBF kernel), and sigmoid kernel function for MKL. By generating the synthetic samples
    in the minority class, searching the best choices of the SVM parameters and identifying
    the weights of MKL by minimizing the objective function, the improved performance of
    SVM was observed. To prove the strength of the proposed scheme, an experimental study,
    including noisy borderline and real imbalanced datasets was conducted. SVM was applied
    with linear kernel function, RBF kernel, sigmoid kernel function and MKL on all datasets.
    The performance of SVM with all kernel functions was evaluated by using sensitivity,
    G Mean, and F measure. A significantly improved performance of SVM with MKL was
    observed by applying the proposed scheme.
    MeSH terms: Machine Learning; Algorithms; Colon, Sigmoid; Data Mining; Support Vector Machine
  10. Hao, Lim Zhen, Hikmat Said Al-Salim, Norida Ridzuan
    MyJurnal
    The continuous depletion of global oil reserves with the propensity for light distillates
    propels the oil and gas industry to explore heavier fractions of crude oils with significant
    amount of paraffin waxes. However, the precipitation and deposition of waxes during the
    transportation of these waxy crude oils in the pipelines contribute to several issues, such as
    the flowability reduction, excessive pumping cost, and wax gel formation, that adversely
    affect the supposedly steady offshore oil production. As a result, substantial resources are
    expended to resolve these flow assurance problems. The wax inhibitors and pour point
    depressants are developed and modified to meet the wax remediation criteria. Essentially,
    the wax crystals are formed through the nucleation, growth, and agglomeration processes,
    while the deposition of these waxes occurs via molecular diffusion and shear dispersion.
    The wax inhibitors are able to control the growth of wax crystals through nucleation, cocrystallization,
    adsorption, and dispersion interactions. This paper particularly assessed
    the following compounds: (1) polymeric wax inhibitors, (2) nano-hybrid pour point
    depressants, (3) organic solvents, and
    (4) surfactants. Given the significance of
    these compounds in the deposition and
    precipitation of waxes, it is imperative to
    comprehensively explore the types and
    nature of these compounds and their recent
    applications as well as to critically assess
    their strengths and drawbacks, which were
    addressed in this paper. Furthermore, the
    challenges of using these compounds and the factors that govern their efficiencies were also discussed. Accordingly, the carbon
    length and the molecular weight of both paraffin waxes and wax inhibitors are among the
    most influential factors.
    MeSH terms: Oil and Gas Industry; Adsorption; Carbon; Diffusion; Health Expenditures; Health Resources; Molecular Weight; Paper; Paraffin; Petroleum; Solvents; Surface-Active Agents; Transportation; Waxes
  11. Nur Fitrah Che Nan, Norhazlin Zainuddin, Mansor Ahmad
    MyJurnal
    Carboxymethylcellulose (CMC) is a water-soluble polymer, which is widely used in various
    fields such as food additives, textiles, pharmaceuticals and cosmetics. In this study, hydrogel
    was prepared from CMC by using calcium chloride as a crosslinking agent. Optimization
    of the reaction was done through investigation of four different parameters which had
    different percentage of CMC (w/v), percentage of calcium chloride (w/v), reaction time and
    temperature. The gel content and swelling properties of the CMC hydrogel were studied.
    The highest gel content was 85.33% at 7% of CMC (w/v) with 2% of calcium chloride (w/v)
    in 24 hours reaction time at room temperature. The gel content increased with the increasing
    concentration of CMC and CaCl2. This was due to the higher number of functional groups
    of COO- that were available in more concentrated CMC which could crosslink with CaCl2
    to give higher gel content. Increasing the percentage of CaCl2 will increase the electrostatic
    attraction between anionic charges of polymer chains and multivalent cation (Ca2+) that
    leads to increase in ionic crosslinking of CMC. The swelling properties of CMC hydrogel
    showed that the optimum degree of swelling was 45.33 (g/g). The swelling capacity of the
    hydrogel in water decreased with the increase of the gel content of CMC hydrogel. This
    could be due to the increase in the degree of crosslinking of the CMC hydrogel.
    MeSH terms: Anions; Calcium Chloride; Carboxymethylcellulose Sodium; Cations; Cosmetics; Food Additives; Polymers; Reaction Time; Temperature; Textiles; Water; Static Electricity
  12. Abd Ghani Aizat, Paiman, Bawon, Lee, Seng Hua, Ashaari Zaidon
    MyJurnal
    In this study, the effects of addition of ammonium and aluminium-based hardeners into
    urea formaldehyde resin (UF) on the physico-mechanical properties and formaldehyde
    emission of the rubberwood particleboard were investigated. Four types of hardeners,
    namely ammonium chloride (AC), ammonium sulphate (AS), aluminium chloride (AlC)
    and aluminium sulphate (AlS), were added into UF resin. The acidity, gelation time,
    viscosity and free formaldehyde content of the UF/hardener mixtures were determined.
    Particleboard made with the UF/hardener mixtures were tested for physico-mechanical
    properties and formaldehyde emission. The pH values of the resin after addition of
    aluminium-based hardeners were higher and resulted in higher viscosity and shorter
    gelation time. Consequently, despite lower formaldehyde emission was recorded, the
    physico-mechanical properties of the resulted particleboard were inferior compared to
    that of ammonium-based hardeners. The best quality particleboard in terms of mechanical,
    physical and formaldehyde emission were obtained from the particleboard made with AS,
    followed by AC.
    MeSH terms: Alum Compounds; Aluminum; Ammonium Chloride; Ammonium Sulfate; Chlorides; Formaldehyde; Resins, Plant; Urea; Viscosity; Aluminum Compounds; Ammonium Compounds
  13. Nur Azida Che Lah, Muhamad Hellmy Hussin
    MyJurnal
    Titanium (Ti) and Ti-based alloys presence the most widely applied as advanced biomaterials
    in biomedical implant applications. Moreover, these alloys are known to be the most
    valuable metallic materials including spinal cord surgical treatment. It becomes an interest
    due to its advantages compared to others, including its bio compatibility and corrosion
    resistant. However, an issue arises when it comes for permanent implant application as
    the alloy has a possible toxic effect produced from chemical reaction between body fluid
    environments with alloys chemical compositions. It also relies on the performance of
    neighbouring bone tissue to integrate with the implant surface. Abnormalities usually
    happen when surrounding tissue shows poor responses and rejection of implants that would
    leads to body inflammation. These cause an increase in foreign body reaction leading to
    severe body tissue response and thus, loosening of the implant. Corrosion effects and
    biocompatibility behaviour of implantation usage also become one of the reasons of
    implant damage. Here, this paper reviews the importance of using Ti and Ti-based alloys
    in biomedical implantation, especially in orthopaedic spinal cord injury. It also reviews the
    basic aspects of corrosion effects that lead to implant mechanical damage, poor response
    of body rejection and biocompatibility behaviour of implantation usage.
    MeSH terms: Alloys; Biocompatible Materials; Body Fluids; Bone and Bones; Corrosion; Foreign-Body Reaction; Orthopedics; Spinal Cord Injuries; Titanium; Prostheses and Implants
  14. Lim, Wei Jie, Chin, Nyuk Ling, Yus AnizaYusof, Azmi Yahya, Tee, Tuan Poy
    MyJurnal
    Anaerobic composting is a promising method to fully transform food wastes into useful
    materials such as biofertilizer and biogas. In this study, the optimum proportions of food
    wastes containing vegetable, fruit and meat wastes with dry leaves or cow manure for
    composting were determined using the simplex centroid design and response optimizer.
    The effectiveness of the pilot-scale composting process was evaluated based on the targeted
    compost quality of C/N ratio at 21, pH value at 8 and electrical conductivity of 1 dS/m.
    Food wastes composting formulation with dry leaves suggested high percentage of dry
    leaves, 86.9% with low food wastes composition of 13.1% constituted by vegetable waste
    (1.1%), fruit waste (4.9%) and meat waste (7.1%). With cow manure formulation, only
    6% of cow manure was recommended with
    another 94.0% of food wastes contributed
    by a fair mix of vegetable waste (23.2%),
    fruit waste (34.3%) and meat waste (36.5%).
    The developed regression models were
    experimentally validated with predicted
    responses obtained in acceptable ranges for
    C/N ratio (21.2 - 21.8), pH (7.92 - 7.99) and
    electrical conductivity (0.97 - 1.03 dS/m).
    MeSH terms: Animals; Cattle; Electric Conductivity; Female; Fruit; Manure; Meat; Vegetables; Plant Leaves; Biofuels
  15. Mahmud H, Ismail A, Abdul Rahim R, Low KO, Md Illias R
    J Biotechnol, 2019 Apr 20;296:22-31.
    PMID: 30878516 DOI: 10.1016/j.jbiotec.2019.02.013
    In previous studies of Lactococcus lactis, the levels of proteins secreted using heterologous signal peptides were observed to be lower than those obtained using the signal peptide from Usp45, the major secreted lactococcal protein. In this study, G1 (the native signal peptide of CGTase) and the signal peptide M5 (mutant of the G1 signal peptide) were introduced into L. lactis to investigate the effect of signal peptides on lactococcal protein secretion to improve secretion efficiency. The effectiveness of these signal peptides were compared to the Usp45 signal peptide. The highest secretion levels were obtained using the G1 signal peptide. Sequence analysis of signal peptide amino acids revealed that a basic N-terminal signal peptide is not absolutely required for efficient protein export in L. lactis. Moreover, the introduction of a helix-breaking residue in the H-region of the M5 signal peptide caused a reduction in the signal peptide hydrophobicity and decreased protein secretion. In addition, the optimization of cultivation conditions for recombinant G1-CGTase production via response surface methodology (RSM) showed that CGTase activity increased approximately 2.92-fold from 5.01 to 16.89 U/ml compared to the unoptimized conditions.
    MeSH terms: Amino Acids; Biochemical Phenomena; Proteins; Lactococcus lactis; Sequence Analysis; Protein Transport; Protein Sorting Signals; Hydrophobic and Hydrophilic Interactions
  16. 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.
    MeSH terms: Animals; Disulfides/chemical synthesis; Disulfides/chemistry*; Equipment Design; Humans; Molybdenum/chemistry*; Biosensing Techniques/instrumentation; Biosensing Techniques/methods*; Nanotechnology/instrumentation; Nanotechnology/methods*; Nanostructures/ultrastructure; Nanostructures/chemistry*
  17. Ardyani T, Mohamed A, Bakar SA, Sagisaka M, Umetsu Y, Mamat MH, et al.
    J Colloid Interface Sci, 2019 Jun 01;545:184-194.
    PMID: 30878784 DOI: 10.1016/j.jcis.2019.03.012
    HYPOTHESIS: The compatibility of surfactants and graphene surfaces can be improved by increasing the number of aromatic groups in the surfactants. Including aniline in the structure may improve the compatibility between surfactant and graphene further still. Surfactants can be modified by incorporating aromatic groups in the hydrophobic chains or hydrophilic headgroups. Therefore, it is of interest to investigate the effects of employing anilinium based surfactants to disperse graphene nanoplatelets (GNPs) in natural rubber latex (NRL) for the fabrication of electrically conductive nanocomposites.

    EXPERIMENTS: New graphene-philic surfactants carrying aromatic moieties in the hydrophilic headgroups and hydrophobic tails were synthesized by swapping the traditional sodium counterion with anilinium. 1H NMR spectroscopy was used to characterize the surfactants. These custom-made surfactants were used to assist the dispersion of GNPs in natural rubber latex matrices for the preparation of conductive nanocomposites. The properties of nanocomposites with the new anilinium surfactants were compared with commercial sodium surfactant sodium dodecylsulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), and the previously synthesized aromatic tri-chain sodium surfactant TC3Ph3 (sodium 1,5-dioxo-1,5-bis(3-phenylpropoxy)-3-((3phenylpropoxy)carbonyl) pentane-2-sulfonate). Structural properties of the nanocomposites were studied using Raman spectroscopy, field emission scanning electron microscopy (FESEM), and high-resolution transmission electron microscopy (HRTEM). Electrical conductivity measurements and Zeta potential measurements were used to assess the relationships between total number of aromatic groups in the surfactant molecular structure and nanocomposite properties. The self-assembly structure of surfactants in aqueous systems and GNP dispersions was assessed using small-angle neutron scattering (SANS).

    FINDINGS: Among these different surfactants, the anilinium version of TC3Ph3 namely TC3Ph3-AN (anilinium 1,5-dioxo-1,5-bis(3-phenylpropoxy)-3-((3phenylpropoxy)carbonyl) pentane-2-sulfonate) was shown to be highly efficient for dispersing GNPs in the NRL matrices, increasing electrical conductivity eleven orders of magnitude higher than the neat rubber latex. Comparisons between the sodium and anilinium surfactants show significant differences in the final properties of the nanocomposites. In general, the strategy of increasing the number of surfactant-borne aromatic groups by incorporating anilinium ions in surfactant headgroups appears to be effective.

    MeSH terms: Alkanesulfonates; Aniline Compounds; Benzenesulfonates; Electric Conductivity; Graphite; Ions; Latex; Microscopy, Electron, Scanning; Magnetic Resonance Spectroscopy; Pentanes; Rubber; Sodium; Sodium Dodecyl Sulfate; Spectrum Analysis, Raman; Surface-Active Agents; Molecular Structure; Microscopy, Electron, Transmission; Nanocomposites; Scattering, Small Angle
  18. Bauer M, Glenn T, Alda M, Andreassen OA, Angelopoulos E, Ardau R, et al.
    J Psychiatr Res, 2019 06;113:1-9.
    PMID: 30878786 DOI: 10.1016/j.jpsychires.2019.03.001
    In many international studies, rates of completed suicide and suicide attempts have a seasonal pattern that peaks in spring or summer. This exploratory study investigated the association between solar insolation and a history of suicide attempt in patients with bipolar I disorder. Solar insolation is the amount of electromagnetic energy from the Sun striking a surface area on Earth. Data were collected previously from 5536 patients with bipolar I disorder at 50 collection sites in 32 countries at a wide range of latitudes in both hemispheres. Suicide related data were available for 3365 patients from 310 onset locations in 51 countries. 1047 (31.1%) had a history of suicide attempt. There was a significant inverse association between a history of suicide attempt and the ratio of mean winter solar insolation/mean summer solar insolation. This ratio is smallest near the poles where the winter insolation is very small compared to the summer insolation. This ratio is largest near the equator where there is relatively little variation in the insolation over the year. Other variables in the model that were positively associated with suicide attempt were being female, a history of alcohol or substance abuse, and being in a younger birth cohort. Living in a country with a state-sponsored religion decreased the association. (All estimated coefficients p 
    MeSH terms: Age Factors; Bipolar Disorder/complications; Bipolar Disorder/psychology*; Climate; Female; Humans; Male; Middle Aged; Risk Factors; Seasons*; Sex Factors; Suicide, Attempted/psychology*; Suicide, Attempted/statistics & numerical data*; Sunlight*; Age of Onset; Substance-Related Disorders/complications; Substance-Related Disorders/psychology; Internationality
  19. Chofreh AG, Goni FA, Zeinalnezhad M, Navidar S, Shayestehzadeh H, Klemeš JJ
    J Environ Manage, 2019 Jun 01;239:38-47.
    PMID: 30878873 DOI: 10.1016/j.jenvman.2019.03.023
    Inaccessible hygiene water sources and sanitation are one of the sustainability issues that need to be solved. An attempt to solve this problem is to change the conventional system used in the water supply and sewage treatment to sustainable water and waste management. To transform the system, companies initially need to map their business value chain. However, this process is often not receiving a full attention by the organisation. In an academic perspective, there are limited studies that map the value chains of water and waste systems. To overcome this limitation, the present study aims to map the value chain processes of the water and wastewater utility companies towards a sustainability solution. A review of related studies is used to conduct this study. Khuzestan Urban Water and Sewage company in Iran has been selected as case studies. The mapping results indicate a lack of sustainability integration in a water management system that leads to ineffective and inefficient water management. Value chain mapping process is significant for practitioners, particularly in the water and sewage companies, as a starting point for transforming their conventional water management systems towards sustainability. Experts at the company stated that value chain mapping as part of value chain analysis enables organisations to increase operational efficiency and eliminate waste by 57%.
    MeSH terms: Iran; Sewage*; Waste Disposal, Fluid*; Water; Waste Water
  20. Zhang L, Tao Y, Woodring J, Rattana K, Sovannarith S, Rathavy T, et al.
    Int J Epidemiol, 2019 08 01;48(4):1327-1339.
    PMID: 30879066 DOI: 10.1093/ije/dyz037
    BACKGROUND: The Regional Framework for Triple Elimination of Mother-to-Child Transmission (EMTCT) of HIV, Hepatitis B (HBV) and Syphilis in Asia and the Pacific 2018-30 was endorsed by the Regional Committee of WHO Western Pacific in October 2017, proposing an integrated and coordinated approach to achieve elimination in an efficient, coordinated and sustainable manner. This study aims to assess the population impacts and cost-effectiveness of this integrated approach in the Cambodian context.

    METHODS: Based on existing frameworks for the EMTCT for each individual infection, an integrated framework that combines infection prevention procedures with routine antenatal care was constructed. Using decision tree analyses, population impacts, cost-effectiveness and the potential reduction in required resources of the integrated approach as a result of resource pooling and improvements in service coverage and coordination, were evaluated. The tool was assessed using simulated epidemiological data from Cambodia.

    RESULTS: The current prevention programme for 370,000 Cambodian pregnant women was estimated at USD$2.3 ($2.0-$2.5) million per year, including the duration of pregnancy and up to 18 months after delivery. A model estimate of current MTCT rates in Cambodia was 6.6% (6.2-7.1%) for HIV, 14.1% (13.1-15.2%) for HBV and 9.4% (9.0-9.8%) for syphilis. Integrating HIV and syphilis prevention into the existing antenatal care framework will reduce the total time required to provide this integrated care by 19% for health care workers and by 32% for pregnant women, resulting in a net saving of $380,000 per year for the EMTCT programme. This integrated approach reduces HIV and HBV MTCT to 6.1% (5.7-6.5%) and 13.0% (12.1-14.0%), respectively, and substantially reduces syphilis MCTC to 4.6% (4.3-5.0%). Further introduction of either antiviral treatment for pregnant women with high viral load of HBV, or hepatitis B immunoglobulin (HBIG) to exposed newborns, will increase the total cost of EMTCT to $4.4 ($3.6-$5.2) million and $3.3 ($2.7-$4.0) million per year, respectively, but substantially reduce HBV MTCT to 3.5% (3.2-3.8%) and 5.0% (4.6-5.5%), respectively. Combining both antiviral and HBIG treatments will further reduce HBV MTCT to 3.4% (3.1-3.7%) at an increased total cost of EMTCT of $4.5 ($3.7-$5.4) million per year. All these HBV intervention scenarios are highly cost-effective ($64-$114 per disability-adjusted life years averted) when the life benefits of these prevention measures are considered.

    CONCLUSIONS: The integrated approach, using antenatal, perinatal and postnatal care as a platform in Cambodia for triple EMTCT of HIV, HBV and syphilis, is highly cost-effective and efficient.

    MeSH terms: Cambodia/epidemiology; Cost-Benefit Analysis; Female; Hepatitis B/epidemiology; Hepatitis B/prevention & control*; Hepatitis B/transmission; Humans; Infant, Newborn; Pregnancy; Pregnancy Complications, Infectious/epidemiology; Pregnancy Complications, Infectious/prevention & control*; Prenatal Diagnosis/statistics & numerical data; Syphilis/epidemiology; Syphilis/prevention & control*; Syphilis/transmission; World Health Organization; HIV Infections/epidemiology; HIV Infections/prevention & control*; HIV Infections/transmission; Prevalence; Infectious Disease Transmission, Vertical/prevention & control*
External Links