Displaying publications 4021 - 4040 of 8505 in total

Abstract:
Sort:
  1. Tay KW, Ong AWH, Pheh KS, Low SK, Tan CS, Low PK
    Malays J Med Sci, 2019 Nov;26(6):120-126.
    PMID: 31908593 MyJurnal DOI: 10.21315/mjms2019.26.6.12
    Background: Children and young refugees often experience negative events that affect their mental health. Their caregivers may also be in the same predicament, implying that the teachers in schools are a potential source of help and support. However, most teachers have little understanding of mental health and are, thus, clueless in helping their students. To address this need, a newly developed one-day mental health literacy programme was conducted among 68 refugee teachers in Malaysia.

    Methods: Participants learned the symptoms of mental health issues among children and adolescents in the context of post-trauma, provision of early intervention, and channel for professional supports. They also answered a packet of measurements of mental health literacy before and after the programme.

    Results: The paired sample t-test showed that participants reported higher willingness to contact with people having mental health problems (t = 2.787, P = 0.008, Cohen's d = 0.394), less stereotypes toward mental illness (t = 4.603, P < 0.001, d = 0.651) and a better understanding of self-help strategies (t = 2.16, P = .036, d = 0.322) than baseline.

    Conclusion: The results of this study offered preliminary empirical evidence on the effectiveness of the programme as a promising channel for alleviating mental health issues among refugees.

  2. Kee PE, Lan JC, Yim HS, Tan JS, Chow YH, Ng HS
    Appl Biochem Biotechnol, 2020 May;191(1):376-386.
    PMID: 31907777 DOI: 10.1007/s12010-019-03202-y
    Cytochrome c is a small water-soluble protein that is abundantly found in the mitochondrial intermembrane space of microorganism, plants and mammalians. Ionic liquids (ILs)-based aqueous two-phase electrophoresis system (ATPES) was introduced in this study to investigate the partition efficiency of cytochrome c to facilitate subsequent development of two-phase electrophoresis for the separation of cytochrome c from microbial fermentation. The 1-Hexyl-3-methylimidazolium bromide, (C6mim)Br and potassium citrate salt were selected as the phase-forming components. Effects of phase composition; position of electrodes; pH and addition of neutral salt on the partition efficiency of cytochrome c in the ATPES were evaluated. Highest partition coefficient (K = 179.12 ± 0.82) and yield of cytochrome c in top phase (YT = 99.63% ± 0.00) were recorded with IL/salt ATPES composed of 30% (w/w) (C6mim)Br and 20% (w/w) potassium citrate salt of pH 7 and 3.0% (w/w) NaCl addition with anode at the bottom phase and cathode at the top phase. The SDS-PAGE profile revealed that cytochrome c with a molecular weight of 12 kDa was preferably partitioned to the IL-rich top phase. Present findings suggested that the single-step ATPES is a potential separation approach for the recovery of cytochrome c from microbial fermentation. Graphical Abstract.
  3. De S, Selvan VT, Tan J, Soe HHK, Sahoo S, Sahoo R
    PMID: 31867395 DOI: 10.4103/jehp.jehp_379_19
    BACKGROUND: Cancer cervix is caused by human papillomavirus (HPV), oncogenic virus and has vaccines and screening as its preventive measures. This study analyzes the change in awareness and attitudes of nonmedical students toward the condition following the use of an educational module.

    METHODOLOGY: The study design was quasi-experimental. The interprofessional (IP) team implemented an educational module and analyzed the difference in awareness of young individuals toward the cancer cervix. A pretest and posttest written questionnaire, customized for both genders, was administered with the intervention of the educational module in between. The module consisted of a short educational presentation along with a group activity. A follow-up survey was also done after 2 months to check the attrition of awareness. The statistical analysis was done using MacNemar test using SPSS 12 IBM software and significance of differences were determined.

    RESULTS: There was a significant improvement of knowledge and awareness on linkage between HPV and cervical cancer (P < 0.001). There was also significant change with regard to attitudes toward cervical cancer vaccination (P = 0.004). The knowledge of HPV linkage to the malignancy was maintained after 2 months of gap. The subjects also wished for more future awareness program.

    CONCLUSIONS: There is improved awareness in the dental and foundation in science students, and this improved awareness will ensure favorable attitudes toward cervical cancer vaccines or will attend regular screening programs. Awareness program must be held at regular intervals at different locations to enhance the knowledge dissemination of this common yet preventable genital malignancy of females. The IP collaboration and practices will help in reducing the disease burden of the society in future.

  4. Lim FS, Khoo JJ, Tan KK, Zainal N, Loong SK, Khor CS, et al.
    Ticks Tick Borne Dis, 2020 03;11(2):101352.
    PMID: 31866439 DOI: 10.1016/j.ttbdis.2019.101352
    Ticks are hematophagous vectors of arthropod-borne disease agents globally. In Malaysia, despite seroprevalence studies indicating the presence of tick-borne diseases among the indigenous people, the etiological agents of these diseases are still unclear. These indigenous people, also known as the Orang Asli, still live in forested areas with frequent contact with wildlife. Wild boar are ubiquitously found in the forested areas where the Orang Asli communities are located and are commonly hunted as a food supplement. In this study, we aim to determine the tick species parasitizing wild boar from an Orang Asli community, and explore the tick-associated bacterial communities using 16 s rRNA amplicon sequencing on the Ion Torrent PGM™ platform. A total of 72 ticks were collected from three wild boar and were morphologically identified as Haemaphysalis hystricis (n = 32), Dermacentor compactus (n = 15), Amblyomma testudinarium (n = 13), Dermacentor steini (n = 10) and Dermacentor atrosignatus (n = 2). Across all tick samples, 910 bacterial taxa were identified. Although the bacterial communities were not significantly distinct between tick species in beta-diversity analyses, Coxiella, Rickettsia and Francisella were detected at high relative abundance in H. hystricis, D. compactus and D. steini respectively. Many other bacterial genera, including those that have been described in many different tick species, were also identified, including Pseudomonas, Acinetobacter, Staphylococcus and Corynebacterium. Beta-diversity analyses also showed that the bacterial communities were separated based on the animal host from which the ticks were collected from, suggesting that the bacterial communities here may be influenced by the animal skin microflora, host blood or the environment. PCR screening confirmed the presence of Rickettsia sp. related to spotted fever group Rickettsia in some of the ticks. This study provides baseline knowledge of the microbiome of H. hystricis, D. atrosignatus, D. compactus, D. steini and A. testudinarium parasitizing wild boar in this region. The information gained in this study provides the basis to target our efforts in H. hystricis, D. compactus and D. steini for the future investigation of vector competence and the zoonotic potential for the Coxiella, Rickettsia and Francisella detected here, as well as their implications for the risks of tick-borne diseases among the Orang Asli communities.
  5. Lei M, Zhang N, Lee WJ, Tan CP, Lai OM, Wang Y, et al.
    Food Chem, 2020 May 15;312:126047.
    PMID: 31884300 DOI: 10.1016/j.foodchem.2019.126047
    Formation of foams is critical for tailoring the texture and mouthfeel of fat-based products. Diacylglycerol (DAG) is regarded as a preferable alternative structurant to hydrogenated lipid. Effect of DAG concentration (2-10 wt%) on the characteristics of oleogels and foams including crystal polymorphisms, size and distribution, rheological and thermodynamic properties was investigated. Oleogel prepared with 10 wt% DAG had comparable whipping and foaming stability to that of 6 wt% fully hydrogenated palm oil (FHPO). DAG formed small plate-crystals which tend to occur at the bubble surface, whereas FHPO showed needle-like crystals that were formed mainly in the continuous phase. For the 2 wt% FHPO-8 wt% DAG-based oil foams, interfacial templating crystallization effect contributed to the smaller bubble size and improved rheological properties whereby less oil drainage and foam breakdown occurred. Hence, the non-aqueous foam formed by DAG has broad application prospect because of the thermoresponsive properties and the desirable health benefits.
  6. Tay YL, Amanah A, Adenan MI, Wahab HA, Tan ML
    Sci Rep, 2019 12 24;9(1):19757.
    PMID: 31874991 DOI: 10.1038/s41598-019-56106-6
    Mitragyna speciosa Korth (M. speciosa) has been widely used as a recreational product, however, there are growing concerns on the abuse potentials and toxicity of the plant. Several poisoning and fatal cases involving kratom and mitragynine have been reported but the underlying causes remain unclear. The human ether-a-go-go-related gene 1 (hERG1) encodes the pore-forming subunit underlying cardiac rapidly delayed rectifier potassium current (IKr). Pharmacological blockade of the IKr can cause acquired long QT syndrome, leading to lethal cardiac arrhythmias. This study aims to elucidate the mechanisms of mitragynine-induced inhibition on hERG1a/1b current. Electrophysiology experiments were carried out using Port-a-Patch system. Quantitative RT-PCR, Western blot analysis, immunofluorescence and co-immunoprecipitation methods were used to determine the effects of mitragynine on hERG1a/1b expression and hERG1-cytosolic chaperones interaction. Mitragynine was found to inhibit the IKr current with an IC50 value of 332.70 nM. It causes a significant reduction of the fully-glycosylated (fg) hERG1a protein expression but upregulates both core-glycosylated (cg) expression and hERG1a-Hsp90 complexes, suggesting possible impaired hERG1a trafficking. In conclusion, mitragynine inhibits hERG1a/1b current through direct channel blockade at lower concentration, but at higher concentration, it upregulates the complexation of hERG1a-Hsp90 which may be inhibitory towards channel trafficking.
  7. Preeyaa SU, Murugesan A, Sopnajothi S, Yong YK, Tan HY, Larsson M, et al.
    Viral Immunol, 2020 11;33(9):610-615.
    PMID: 32996843 DOI: 10.1089/vim.2020.0149
    Peripheral follicular helper T (pTfh) cells represent specialized CD4+ T cells that help B cells to secrete antibodies. Dengue infection appears to cause immune activation in a wide array of immune cells. Herein, we investigated the signatures of immune activation of circulating Tfh cells and mucosal-associated invariant T (MAIT) cells in adult subjects with confirmed acute clinical dengue virus (DENV) infection by multiparametric flow cytometry. The acute DENV infection induced a significant expansion of highly activated pTfh cells and circulating MAIT cells during acute febrile infection. We found a higher frequency of activated PD-1+ Tfh cells and CD38+ pTfh cells in clinical DENV infection. We also found similar activated and expanding phenotypes of MAIT cells in the patients tested. The total counts of activated pTfh cells and circulating MAIT cells were higher in dengue patients relative to healthy controls. We concluded that pTfh cells and circulating MAIT cells represent activated phenotypes in acute DENV infection.
  8. Gould-Fensom L, Tan CBY, Brooks KR, Mond J, Stevenson RJ, Stephen ID
    Front Psychol, 2019;10:2532.
    PMID: 31803097 DOI: 10.3389/fpsyg.2019.02532
    Visual adaptation has been proposed as a mechanism linking viewing images of thin women's bodies with body size and shape misperception (BSSM). Non-Caucasian populations appear less susceptible to BSSM, possibly because adaptation to thin Caucasian bodies in Western media may not fully transfer to own-race bodies. Experiment 1 used a cross-adaptation paradigm to examine the transfer of body size aftereffects across races. Large aftereffects were found in the predicted directions for all conditions. The strength of aftereffects was statistically equivalent when the race of test stimuli was congruent vs. incongruent with the race of adaptation stimuli, suggesting complete transfer of aftereffects across races. Experiment 2 used a contingent-adaptation paradigm, finding that simultaneous adaptation to wide Asian and narrow Caucasian women's bodies (or vice versa) results in no significant aftereffects for either congruent or incongruent conditions and statistically equivalent results for each. Equal and opposite adaptation effects may therefore transfer completely across races, canceling each other out. This suggests that body size is encoded by a race-general neural mechanism. Unexpectedly, Asian observers showed reduced body size aftereffects compared to Caucasian observers, regardless of the race of stimulus bodies, perhaps helping to explain why Asian populations appear less susceptible to BSSM.
  9. Khairuddin A, Ong GH, Tan JS, Johan S, Hoe VC, Sharif MS, et al.
    Int J Surg Case Rep, 2020;66:104-106.
    PMID: 31830742 DOI: 10.1016/j.ijscr.2019.11.055
    INTRODUCTION: Laparoscopic liver resection is currently performed as a therapeutic modality in hepatocellular carcinoma (HCC). In an emergency setting such as bleeding or rupture, however it has not been well documented.

    PRESENTATION OF CASE: We describe a 55-year-old lady who presented to the emergency department with epigastric pain and symptoms of anaemia for one day duration. She was normotensive but tachycardic. Blood investigations revealed haemoglobin level of 6.5 g/dL and serum alpha-fetoprotein of 3136 g/dL. Contrast enhanced computed tomography scan revealed ruptured HCC of segment 2 and 3. She underwent emergency laparoscopic resection of the ruptured HCC. The postoperative recovery was uneventful and she was discharged well on postoperative day 7. Histology confirmed a 10 cm ruptured HCC with 3 mm tumour-free resection margin.

    DISCUSSION: Ruptured HCC is associated with a high mortality rate of 25-75 %. Traditional treatment involves initial stabilization and hemostasis through transarterial embolization followed by staged hepatic resection. However, laparoscopic liver resection has been shown to be superior than open surgery in terms of postoperative outcomes.

    CONCLUSION: Laparoscopic resection of bleeding HCC is achievable and can be considered in the treatment algorithm of selected patients.

  10. Kadar M, Wan Yunus F, Tan E, Chai SC, Razaob Razab NA, Mohamat Kasim DH
    Aust Occup Ther J, 2020 02;67(1):3-12.
    PMID: 31799722 DOI: 10.1111/1440-1630.12626
    INTRODUCTION: Handwriting skills play a significant role in all stages of an individual's life. Writing interventions should be considered at a younger age to ensure proper development of writing skills. Hence, the aims of this study is to evaluate the current evidence of occupational therapy interventions in handwriting skills for 4-6 year old children.

    METHODS: Published literature was systematically searched according to PRISMA guidelines using specific key terms. Initial search identified 785 studies; however only seven met the inclusion criteria and were assessed for final review. Studies were methodologically appraised using the McMaster Critical Review Form-Quantitative Studies.

    RESULTS: The review found no randomised control trial study design pertaining to the reviewed area. However, it can be seen that occupational therapy interventions for writing skills in 4-6 year old children managed to increase the targeted skills. The results were similar across samples with or without disabilities. An effective integration of occupational therapy interventions into educational curriculum was found to save both time and cost.

    CONCLUSION: The long-term benefit from these interventions and the effects of these interventions on a broader spectrum of fine motor abilities need to be explored further with stronger research designs. However, the lack of studies adopting high level study designs, i.e., RCT designs means, results need to be approached with caution by occupational therapists when implementing handwriting skills intervention in practice.

  11. Lo TS, Tan YL, Pue LB, Chua S, Wu MP, Hsieh WC
    Int Urogynecol J, 2020 09;31(9):1949-1957.
    PMID: 32006069 DOI: 10.1007/s00192-019-04213-3
    INTRODUCTION AND HYPOTHESIS: Mixed urinary incontinence (MUI) is defined as symptomatic complaint of involuntary leakage associated with urgency and also with exertion, effort, sneezing or coughing. The paucity of research, especially on the surgical management of MUI, limits its best management.

    METHODS: This is a retrospective study to determine the outcomes of mixed urinary incontinence after mid-urethral sling surgery with two groups, urodynamic stress incontinence (USI) with urgency and urodynamic mixed urinary incontinence (MUI-UD; USI and detrusor overactivity [DO]).

    RESULTS: Ninety women (USI + urgency group) with preoperative USI and urgency and no demonstrable DO/DOI attained an objective cure of 82.2%, whereas the remaining 67 (MUI-UD group) women with both USI and DO/DOI were reported to have an objective cure of only 55.2%. Subjective cures were 81.1% and 53.7% respectively. The type of incontinence surgery does not affect postoperative outcomes in either of the groups. Demographic factors identified to have a significant negative effect on cure rates were postmenopausal status (p = 0.005), prior hysterectomy (p = 0.028), pre-operative smaller blafdder capacity (p = 0.001), and a larger volume of pre-operative pad test (p = 0.028). A lower mid-urethral closure pressure (MUCP) was significant with post-operative failure of treatment with MUI-UD group (68.8 ± 36.2 cmH2O vs 51.9 ± 24.7 cmH2O; p = 0.033).

    CONCLUSIONS: Although there is evidence for a good cure of the stress component of MUI, urodynamic investigation with its findings prior to management of MUI could have greater implications for selective patient centered counseling. Presence of DO or DOI on urodynamics resulted in poorer objective and subjective outcomes.

  12. Muniandy K, Tan MH, Shehnaz S, Song BK, Ayub Q, Rahman S
    Planta, 2020 Feb 01;251(2):57.
    PMID: 32008119 DOI: 10.1007/s00425-020-03349-7
    MAIN CONCLUSION: The rice leaf mitochondrial DNA is  more methylated compared to the rice grain mitochondrial DNA. The old rice leaf mitochondrial DNA has also a higher methylation level than the young rice leaf mitochondrial DNA. The presence of DNA methylation in rice organelles has not been well characterized. We have previously shown that cytosine methylation of chloroplast DNA is different between leaf and grain, and varies between young and old leaves in rice. However, the variation in cytosine methylation of mitochondrial DNA is still poorly characterized. In this study, we have investigated cytosine methylation of mitochondrial DNA in the rice grain and leaf. Based on CpG, CHG, and CHH methylation analyses, the leaf mitochondrial DNA was found to be  more methylated compared to the grain mitochondrial DNA. The methylation of the leaf mitochondrial DNA was also higher in old compared to young leaves. Differences in methylation were observed at different cytosine positions of the mitochondrial DNA between grain and leaf, although there were also positions with a similar level of high methylation in all the tissues examined. The differentially methylated cytosine positions in rice mitochondrial DNA were observed mostly in the intergenic region and in some mitochondrial-specific genes involved in ATP production, transcription, and translation. The functional importance of cytosine methylation in the life cycle of rice mitochondria is still to be determined.
  13. Tan K, Zhang H, Lim LS, Ma H, Li S, Zheng H
    Front Immunol, 2019;10:3041.
    PMID: 32010132 DOI: 10.3389/fimmu.2019.03041
    Carotenoids are biologically active pigments that are well-known to enhance the defense and immunity of the vertebrate system. However, in invertebrates, the role of carotenoids in immunity is not clear. Therefore, this study aims to review the scientific evidence for the role of carotenoids in invertebrate immunization. From the analysis of published literatures and recent studies from our laboratory, it is obvious that carotenoids are involved in invertebrate immunity in two ways. On the one hand, carotenoids can act as antioxidant enzymes to remove singlet oxygen, superoxide anion radicals, and hydroxyl radicals, thereby reducing SOD activity and reducing the cost of immunity. In some organisms, carotenoids have been shown to promote SOD activity by up-regulating the expression of the ZnCuSOD gene. Carotenoids, on the other hand, play a role in the expression and regulation of many genes involved in invertebrate immunity, including thioredoxins (TRX), peptidoglycan recognition receptor proteins (PGRPs), ferritins, prophenoloxidase (ProPO), vitellogenin (Vg), toll-like receptor (TLRs), heat shock proteins (HSPs), and CuZnSOD gene. The information in this review is very useful for updating our understanding of the progress of carotenoid research in invertebrate immunology and to help identify topics for future topics.
  14. Wong JJ, Tan HL, Lee SW, Chang KTE, Mok YH, Lee JH
    Pediatr Pulmonol, 2020 04;55(4):1000-1006.
    PMID: 32017471 DOI: 10.1002/ppul.24674
    OBJECTIVE: This study delineates the disease trajectory of patients with pediatric acute respiratory distress syndrome (PARDS) defined by the Pediatric Acute Lung Injury Consensus Conference (PALICC) definition, and evaluates the impact of comorbidities on outcomes.

    METHODS: This prospective study over November 2017-October 2019 was conducted in a single-center multidisciplinary pediatric intensive care unit (PICU) and included patients <21years of age with PARDS. Clinical history of those requiring mechanical ventilation for <3 days was interrogated and cases in which the diagnosis of PARDS were unlikely, identified. The impact of chronic comorbidities on clinical outcomes, in particular, pulmonary disease and immunosuppression, were analyzed.

    RESULTS: Eighty-five of 1272 PICU admissions (6.7%) met the criteria for PARDS and were included. Median age and oxygenation indexes were 2.8 (0.6, 8.3) years and 10.6 (7.6, 15.4), respectively. Overall mortality was 12 out of 85 (14.1%). Despite fulfilling criteria in 6/85 (7.1%), hypoxemia contributed by bronchospasm, mucus plugging, fluid overload, and atelectasis was quickly reversible and PARDS was unlikely in these patients. Comorbidities (57/85 [67.1%]) were not associated with worsened outcomes. However, pre-existing pulmonary disease and immunosuppression were associated with severe PARDS (12/20 [60.0%] vs 19/65 [29.2%]; P = .017), extracorporeal membrane oxygenation use (5/20 [25.0%] vs 3/65 [4.6%]; P = .016) and reduced ventilator free days (VFD) (15 [0, 19] vs 21 [6, 23]; P = .039), compared with those without them.

    CONCLUSION: A small percentage of children fulfilling the PALICC definition had quickly reversible hypoxemia with likely alternate pathophysiology to PARDS. Patients with pulmonary comorbidities and immunosuppression had a more severe course of PARDS compared with others.

  15. Salvamani S, Tan HZ, Thang WJ, Ter HC, Wan MS, Gunasekaran B, et al.
    Br J Biomed Sci, 2020 Oct;77(4):168-184.
    PMID: 32942955 DOI: 10.1080/09674845.2020.1826136
    The COVID-19 disease is caused by the SARS-CoV-2 virus, which is highly infective within the human population. The virus is widely disseminated to almost every continent with over twenty-seven million infections and over ninety-thousand reported deaths attributed to COVID-19 disease. SARS-CoV-2 is a single stranded RNA virus, comprising three main viral proteins; membrane, spike and envelope. The clinical features of COVID-19 disease can be classified according to different degrees of severity, with some patients progressing to acute respiratory distress syndrome, which can be fatal. In addition, many infections are asymptomatic or only cause mild symptoms. As there is no specific treatment for COVID-19 there is considerable endeavour to raise a vaccine against SARS-CoV-2, in addition to engineering neutralizing antibody interventions. In the absence of an effective vaccine, movement controls of varying stringencies have been imposed. Whilst enforced lockdown measures have been effective, they may be less effective against the current strain of SARS-CoV-2, the G614 clade. Conversely, other mutations of the virus, such as the Δ382 variant could reduce the clinical relevance of infection. The front runners in the race to develop an effective vaccine focus on the SARS-Co-V-2 Spike protein. However, vaccines that produce a T-cell response to a wider range of SARS-Co-V-2 viral proteins, may be more effective. Population based studies that determine the level of innate immunity to SARS-CoV-2, from prior exposure to the virus or to other coronaviruses, will have important implications for government imposed movement control and the strategic delivery of vaccination programmes.
  16. Bui TD, Tsai FM, Tseng ML, Tan RR, Yu KDS, Lim MK
    Sustain Prod Consum, 2021 Apr;26:373-410.
    PMID: 33015266 DOI: 10.1016/j.spc.2020.09.017
    Balancing sustainability and disruption of supply chains requires organizational ambidexterity. Sustainable supply chains prioritize efficiency and economies of scale and may not have sufficient redundancy to withstand disruptive events. There is a developing body of literature that attempts to reconcile these two aspects. This study gives a data-driven literature review of sustainable supply chain management trends toward ambidexterity and disruption. The critical review reveals temporal trends and geographic distribution of literature. A hybrid of data-driven analysis approach based on content and bibliometric analyses, fuzzy Delphi method, entropy weight method, and fuzzy decision-making trial and evaluation laboratory is used on 273 keywords and 22 indicators obtained based on the experts' evaluation. The most important indicators are identified as supply chain agility, supply chain coordination, supply chain finance, supply chain flexibility, supply chain resilience, and sustainability. The regions show different tendencies compared with others. Asia and Oceania, Latin America and the Caribbean, and Africa are the regions needs improvement, while Europe and North America show distinct apprehensions on supply chain network design. The main contribution of this review is the identification of the knowledge frontier, which then leads to a discussion of prospects for future studies and practical industry implementation.
  17. Azaman SNA, Satharasinghe DA, Tan SW, Nagao N, Yusoff FM, Yeap SK
    Genes (Basel), 2020 09 25;11(10).
    PMID: 32992970 DOI: 10.3390/genes11101131
    Chlorella is a popular microalga with robust physiological and biochemical characteristics, which can be cultured under various conditions. The exploration of the small RNA content of Chlorella could improve strategies for the enhancement of metabolite production from this microalga. In this study, stress was introduced to the Chlorella sorokiniana culture to produce high-value metabolites such as carotenoids and phenolic content. The small RNA transcriptome of C. sorokiniana was sequenced, focusing on microRNA (miRNA) content. From the analysis, 98 miRNAs were identified in cultures subjected to normal and stress conditions. The functional analysis result showed that the miRNA targets found were most often involved in the biosynthesis of secondary metabolites, followed by protein metabolism, cell cycle, and porphyrin and chlorophyll metabolism. Furthermore, the biosynthesis of secondary metabolites such as carotenoids, terpenoids, and lipids was found mostly in stress conditions. These results may help to improve our understanding of regulatory mechanisms of miRNA in the biological and metabolic process of Chlorella species. It is important and timely to determine the true potential of this microalga species and to support the potential for genetic engineering of microalgae as they receive increasing focus for their development as an alternative source of biofuel, food, and health supplements.
  18. Quah RV, Tan YH, Mubarak NM, Kansedo J, Khalid M, Abdullah EC, et al.
    Waste Manag, 2020 Dec;118:626-636.
    PMID: 33011540 DOI: 10.1016/j.wasman.2020.09.016
    Due to its environment-friendly and replenishable characteristics, biodiesel has the potential to substitute fossil fuels as an alternative source of energy. Although biodiesel has many benefits to offer, manufacturing biodiesel on an industrial scale is uneconomical as a high cost of feedstock is required. A novel sulfonated and magnetic catalyst synthesised from a palm kernel shell (PMB-SO3H) was first introduced in this study for methyl ester or biodiesel production to reduce capital costs. The wasted palm kernel shell (PKS) biochar impregnated with ferrite Fe3O4 was synthesised with concentrated sulphuric acid through the sulfonation process. The SEM, EDX, FTIR, VSM and TGA characterization of the catalysts were presented. Then, the optimisation of biodiesel synthesis was catalysed by PMB-SO3H via the Response Surface Methodology (RSM). It was found that the maximum biodiesel yield of 90.2% was achieved under these optimum operating conditions: 65 °C, 102 min, methanol to oil ratio of 13:1 and the catalyst loading of 3.66 wt%. Overall, PMB-SO3H demonstrated acceptable catalysing capability on its first cycle, which subsequently showed a reduction of the reusability performance after 4 cycles. An important practical implication is that PMB-SO3H can be established as a promising heterogeneous catalyst by incorporating an iron layer which can substantially improve the catalyst separation performance in biodiesel production.
Filters
Contact Us

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

External Links