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  1. Comparative analysis of antioxidant and antiproliferative activities of Rhodomyrtus tomentosa extracts prepared with various solvents
    Abd Hamid H, Mutazah R, Yusoff MM, Abd Karim NA, Abdull Razis AF
    Food Chem Toxicol, 2017 Oct;108(Pt B):451-457.
    PMID: 27725206 DOI: 10.1016/j.fct.2016.10.004
    Rhodomyrtus tomentosa (Aiton) Hassk. has a wide spectrum of pharmacological effects and has been used to treat wounds, colic diarrhoea, heartburns, abscesses and gynaecopathy. The potential antiproliferative activities of R. tomentosa extracts from different solvents were evaluated in vitro on HepG2, MCF-7 and HT 29 cell lines while antioxidant activity was monitored by radical scavenging assay (DPPH), copper reducing antioxidant capacity (CUPRAC) and β-carotene bleaching assay. Extracts from R. tomentosa show the viability of the cells in concentration-dependent manner. According to the IC50 obtained, the ethyl acetate extracts showed significant antiproliferative activity on HepG2 (IC50 11.47 ± 0.280 μg/mL), MCF-7 (IC50 2.68 ± 0.529 μg/mL) and HT 29 (IC50 16.18 ± 0.538 μg/mL) after 72 h of treatment. Bioassay guided fractionation of the ethyl acetate extract led to the isolation of lupeol. Methanol extracts show significant antioxidant activities in DPPH (EC50 110.25 ± 0.005 μg/ml), CUPRAC (EC50 53.84 ± 0.004) and β-carotene bleaching (EC50 58.62 ± 0.001) due to the presence of high total flavonoid and total phenolic content which were 110.822 ± 0.017 mg butylated hydroxytoluene (BHT)/g and 190.467 ± 0.009 mg gallic acid (GAE)/g respectively. Taken together, the results extracts show the R. tomentosa as a potential source of antioxidant and antiproliferative efficacy.
  2. In vitro cytotoxicity of Clinacanthus nutans fractions on breast cancer cells and molecular docking study of sulphur containing compounds against caspase-3
    Mutazah R, Hamid HA, Mazila Ramli AN, Fasihi Mohd Aluwi MF, Yusoff MM
    Food Chem Toxicol, 2019 Oct 15.
    PMID: 31626839 DOI: 10.1016/j.fct.2019.110869
    Clinacanthus nutans has attracted Malaysian public interest due to its high medicinal value in the prevention of cancer. Currently, the specific compound or compounds giving rise to the anticancer potential of C. nutans has not been investigated thoroughly. The extraction was carried out by MeOH at room temperature using the powdered bark of C. nutans, while chromatography was carried out on a silica gel RP-18 column using the crude methanolic extract. Six fractions collected from column chromatography were evaluated by MTT assay against two breast cancer cell lines: MDA-MB-231 and MCF-7. Amongst the fractions, A12 and A17 were shown to exhibit the highest activity. Two sulphur-containing compounds, viz., entadamide C (1) and clinamide D (2), were isolated from these fractions. Molecular docking simulation studies revealed that entadamide C and clinamide D could bind favourably to the caspase-3 binding site with the binding energy of -4.28 kcal/mol and -4.84 kcal/mol, respectively. This study provides empirical evidence for the presence of sulphur-containing compounds in the leaves of C. nutans that displayed anticancer effects which explains its ethnomedicinal application against breast cancer. The docking simulation study showed that both compounds could serve as important templates for future drug design and development.
  3. Nanostructured materials from hydroxyethyl cellulose for skin tissue engineering
    Zulkifli FH, Hussain FSJ, Rasad MSBA, Mohd Yusoff M
    Carbohydr Polym, 2014 Dec 19;114:238-245.
    PMID: 25263887 DOI: 10.1016/j.carbpol.2014.08.019
    In this study, a novel fibrous membrane of hydroxyethyl cellulose (HEC)/poly(vinyl alcohol) blend was successfully fabricated by electrospinning technique and characterized. The concentration of HEC (5%) with PVA (15%) was optimized, blended in different ratios (30-50%) and electrospun to get smooth nanofibers. Nanofibrous membranes were made water insoluble by chemically cross-linking by glutaraldehyde and used as scaffolds for the skin tissue engineering. The microstructure, morphology, mechanical and thermal properties of the blended HEC/PVA nanofibrous scaffolds were characterized by scanning electron microscope, Fourier transform infrared spectroscopy, differential scanning colorimetry, universal testing machine and thermogravimetric analysis. Cytotoxicity studies on these nanofibrous scaffolds were carried out using human melanoma cells by the MTT assays. The cells were able to attach and spread in the nanofibrous scaffolds as shown by the SEM images. These preliminary results show that these nanofibrous scaffolds that supports cell adhesion and proliferation is promising for skin tissue engineering.
  4. Fulltext Physiological and growth response of rice plants (Oryza sativa L.) to Trichoderma spp. inoculants
    Doni F, Isahak A, Che Mohd Zain CR, Wan Yusoff WM
    AMB Express, 2014;4:45.
    PMID: 24949276 DOI: 10.1186/s13568-014-0045-8
    Trichoderma spp., a known beneficial fungus is reported to have several mechanisms to enhance plant growth. In this study, the effectiveness of seven isolates of Trichoderma spp. to promote growth and increase physiological performance in rice was evaluated experimentally using completely randomized design under greenhouse condition. This study indicated that all the Trichoderma spp. isolates tested were able to increase several rice physiological processes which include net photosynthetic rate, stomatal conductance, transpiration, internal CO2 concentration and water use efficiency. These Trichoderma spp. isolates were also able to enhance rice growth components including plant height, leaf number, tiller number, root length and root fresh weight. Among the Trichoderma spp. isolates, Trichoderma sp. SL2 inoculated rice plants exhibited greater net photosynthetic rate (8.66 μmolCO2 m(-2) s(-1)), internal CO2 concentration (336.97 ppm), water use efficiency (1.15 μmoCO2/mmoH2O), plant height (70.47 cm), tiller number (12), root length (22.5 cm) and root fresh weight (15.21 g) compared to the plants treated with other Trichoderma isolates tested. We conclude that beneficial fungi can be used as a potential growth promoting agent in rice cultivation.
  5. The role of long chain omega-3 polyunsaturated fatty acids in reducing lipid peroxidation among elderly patients with mild cognitive impairment: a case-control study
    Lee LK, Shahar S, Rajab N, Yusoff NA, Jamal RA, Then SM
    J Nutr Biochem, 2013 May;24(5):803-8.
    PMID: 22898566 DOI: 10.1016/j.jnutbio.2012.04.014
    The present work explores the effect of dietary omega-3 polyunsaturated fatty acids (PUFAs) intake on lipid peroxidation among mild cognitive impairment (MCI) patients. The plasma lipid hydroperoxide (LPO) levels in 67 MCI patients were compared to those of 134 healthy elderly controls. Omega-3 PUFA intake was assessed using an interviewer-administered food frequency questionnaire. Apolipoprotein E genotyping was performed using polymerase chain reaction and restriction enzyme digestion. The association between various confounders and lipid peroxidation was evaluated using regression analysis. The influence of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) intake on LPO level was investigated. The results revealed that LPO levels were significantly higher in the MCI group than in the control group. Inverse correlations were found between DHA and EPA intake and LPO level among the MCI group. LPO levels decreased significantly with increasing DHA and EPA intake. In summary, the findings revealed that DHA and EPA can play a role in alleviating oxidative stress and reducing the risk of neurodegenerative diseases.
  6. Fulltext Combinatorial Antimicrobial Efficacy and Mechanism of Linalool Against Clinically Relevant Klebsiella pneumoniae
    Yang SK, Yusoff K, Ajat M, Wee CY, Yap PS, Lim SH, et al.
    Front Microbiol, 2021;12:635016.
    PMID: 33815320 DOI: 10.3389/fmicb.2021.635016
    Antibiotic-adjuvant combinatory therapy serves as a viable treatment option in addressing antibiotic resistance in the clinical setting. This study was carried out to assess and characterize the adjuvant potential and mode of action of linalool against carbapenemase-producing Klebsiella pneumoniae (KPC-KP). Linalool exhibited bactericidal activity alone (11,250 μg/ml) and in combination with meropenem (5,625 μg/ml). Comparative proteomic analysis showed significant reduction in the number of cytoplasmic and membrane proteins, indicating membrane damage in linalool-treated KPC-KP cells. Upregulation of oxidative stress regulator proteins and downregulation of oxidative stress-sensitive proteins indicated oxidative stress. Zeta potential measurement and outer membrane permeability assay revealed that linalool increases the bacterial surface charge as well as the membrane permeability. Intracellular leakage of nucleic acid and proteins was detected upon linalool treatment. Scanning and transmission electron microscopies further revealed the breakage of bacterial membrane and loss of intracellular materials. Linalool induced oxidative stress by generating reactive oxygen species (ROS) which initiates lipid peroxidation, leading to damage of the bacterial membrane. This leads to intracellular leakage, eventually killing the KPC-KP cells. Our study demonstrated that linalool possesses great potential in future clinical applications as an adjuvant along with existing antibiotics attributed to their ability in disrupting the bacterial membrane by inducing oxidative stress. This facilitates the uptake of antibiotics into the bacterial cells, enhancing bacterial killing.
  7. Application of Bpw34 photodiode and cold white LED as diagnostic X-ray detectors: A comparative analysis
    Damulira E, Yusoff MNS, Omar AF, Mohd Taib NH, Ahmed NM
    Appl Radiat Isot, 2021 Apr;170:109622.
    PMID: 33592486 DOI: 10.1016/j.apradiso.2021.109622
    This study compares the real-time dosimetric performance of a bpw34 photodiode (PD) and cold white light-emitting diodes (LEDs) based on diagnostic X-ray-induced signals. Signals were extracted when both the transducers were under identical exposure settings, including source-to-detector distance (SDD), tube voltage (kVp), and current-time product (mAs). The transducers were in a photovoltaic configuration, and black vinyl tape was applied on transducer active areas as a form of optical shielding. X-ray beam spectra and energies were simulated using Matlab-based Spektr functions. Transducer performance analysis was based on signal linearity to mAs and air kerma, and sensitivity dependence on absorbed dose, energy, and dose rate. Bpw34 PD and cold white LED output signals were 84.8% and 85.5% precise, respectively. PD signals were 94.7% linear to mAs, whereas LED signals were 91.9%. PD and LED signal linearity to dose coefficients were 0.9397 and 0.9128, respectively. Both transducers exhibited similar dose and energy dependence. However, cold white LEDs were 0.73% less dose rate dependent than the bpw34 PD. Cold white LEDs demonstrated potential in detecting diagnostic X-rays because their performance was similar to that of the bpw34 PD. Moreover, the cold white LED array's dosimetric response was independent of the heel effect. Although cold white LED signals were lower than bpw34 PD signals, they were quantifiable and electronically amplifiable.
  8. Ecotoxicological assessment of palm oil mill effluent final discharge by zebrafish (Danio rerio) embryonic assay
    Hashiguchi Y, Zakaria MR, Toshinari M, Mohd Yusoff MZ, Shirai Y, Hassan MA
    Environ Pollut, 2021 May 15;277:116780.
    PMID: 33640825 DOI: 10.1016/j.envpol.2021.116780
    Most palm oil mills adopted conventional ponding system, including anaerobic, aerobic, facultative and algae ponds, for the treatment of palm oil mill effluent (POME). Only a few mills installed a bio-polishing plant to treat POME further before its final discharge. The present study aims to determine the quality and toxicity levels of POME final discharge from three different mills by using conventional chemical analyses and fish (Danio rerio) embryo toxicity (FET) test. The effluent derived from mill A which installed with a bio-polishing plant had lower values of BOD, COD and TSS at 45 mg/L, 104 mg/L, and 27 mg/L, respectively. Only mill A nearly met the industrial effluent discharge standard for BOD. In FET test, effluent from mill A recorded low lethality and most of the embryos were malformed after hatching (half-maximal effective concentration (EC50) = 20%). The highest toxicity was observed from the effluent of mill B and all embryos were coagulated after 24 h in samples greater than 75% of effluent (38% of half-maximal lethal concentration (LC50) at 96 h). The embryos in the effluent from mill C recorded high mortality after hatching, and the survivors were malformed after 96 h exposure (LC50 = 26%). Elemental analysis of POME final discharge samples showed Cu, Zn, and Fe concentrations were in the range of 0.10-0.32 mg/L, 0.01-0.99 mg/L, and 0.94-4.54 mg/L, respectively and all values were below the effluent permissible discharge limits. However, the present study found these metals inhibited D. rerio embryonic development at 0.12 mg/L of Cu, and 4.9 mg/L of Fe for 96 h-EC50. The present study found that bio-polishing plant installed in mill A effectively removing pollutants especially BOD and the FET test was a useful method to monitor quality and toxicity of the POME final discharge samples.
  9. A Rare Case of an Infant with Left Hemiparesis: A Case Report of Bilateral Open-lip Schizencephaly
    Siti BC, Zulkifli MM, Mohd Yusoff SS, Muhamad R, Ahmad TM
    Malays Fam Physician, 2020;15(3):90-94.
    PMID: 33329869
    Schizencephaly is a very rare congenital birth defect. It is characterized by a cortical brain malformation that manifests as a grey-matter-lined cleft extending from the ependyma to the pia mater. It is a rare condition, and few cases have been reported in the literature. The exact cause is unknown. Herein, we report a case of an infant presenting with left side hemiparesis. The CT scan of her brain revealed right fronto-temporal and left parieto-temporal open-lip schizencephaly; thus, urgent referral to a pediatric neurologist was made for early intervention.
  10. Recombinant Enterovirus 71 Viral Protein 1 Fused to a Truncated Newcastle Disease Virus NP (NPt) Carrier Protein
    Mustafa S, Abd-Aziz N, Saw WT, Liew SY, Yusoff K, Shafee N
    Vaccines (Basel), 2020 Dec 07;8(4).
    PMID: 33297428 DOI: 10.3390/vaccines8040742
    Enterovirus 71 (EV71) is the major causative agent in hand, foot, and mouth disease (HFMD), and it mainly infects children worldwide. Despite the risk, there is no effective vaccine available for this disease. Hence, a recombinant protein construct of truncated nucleocapsid protein viral protein 1 (NPt-VP1198-297), which is capable of inducing neutralizing antibody against EV71, was evaluated in a mouse model. Truncated nucleocapsid protein Newcastle disease virus that was used as immunological carrier fused to VP1 of EV71 as antigen. The recombinant plasmid carrying corresponding genes was constructed by recombinant DNA technology and the corresponding protein was produced in Escherichia coli expression system. The recombinant NPt-VP1198-297 protein had elicited neutralizing antibodies against EV71 with the titer of 1:16, and this result is higher than the titer that is elicited by VP1 protein alone (1:8). It was shown that NPt containing immunogenic epitope(s) of VP1 was capable of inducing a greater functional immune response when compared to full-length VP1 protein alone. It was capable to carry larger polypeptide compared to full-length NP protein. The current study also proved that NPt-VP1198-297 protein can be abundantly produced in recombinant protein form by E. coli expression system. The findings from this study support the importance of neutralizing antibodies in EV71 infection and highlight the potential of the recombinant NPt-VP1198-297 protein as EV71 vaccine.
  11. Fulltext Histological changes of immediate skin expansion of the distal limb of rats
    Ali AK, Abubakar AA, Kaka U, Radzi Z, Khairuddin NH, Yusoff MSM, et al.
    Vet World, 2018 Dec;11(12):1706-1711.
    PMID: 30774262 DOI: 10.14202/vetworld.2018.1706-1711
    Aim: Tissue expansion is an applicable technique to reconstruct many surgical defects. The aim of this research was to evaluate the histological changes caused by immediate skin tissue expansion in rats as an animal model.

    Materials and Methods: Immediate skin tissue expansion in 18 adult female rats was performed using three different sizes (small, medium, and big) of polymethylmethacrylate tissue expanders at the dorsal surface of the metatarsal area of the right limb. The contralateral limb was served as the control. The tissue expanders were surgically implanted and kept for 15 days.

    Results: The immediate skin expansion resulted in histological changes such as the increased thickness of the epidermal layer, the reduction of the dermal layer, an elevated number of fibroblast as well as increased vascularity. Furthermore, skin adnexal structures such as hair follicles and sebaceous glands were farther apart.

    Conclusion: The rat skin was able to rapidly adjust and compensate against a specific range of immediate mechanical expansion. The histological changes suggest that the tissues were prepared to withstand the increased external forces, in addition to create possibly additional skin in a relatively short-term period.

  12. Fulltext A comprehensive overview of mitochondrial DNA 4977-bp deletion in cancer studies
    Yusoff AAM, Abdullah WSW, Khair SZNM, Radzak SMA
    Oncol Rev, 2019 Jan 14;13(1):409.
    PMID: 31044027 DOI: 10.4081/oncol.2019.409
    Mitochondria are cellular machines essential for energy production. The biogenesis of mitochondria is a highly complex and it depends on the coordination of the nuclear and mitochondrial genome. Mitochondrial DNA (mtDNA) mutations and deletions are suspected to be associated with carcinogenesis. The most described mtDNA deletion in various human cancers is called the 4977-bp common deletion (mDNA4977) and it has been explored since two decades. In spite of that, its implication in carcinogenesis still unknown and its predictive and prognostic impact remains controversial. This review article provides an overview of some of the cellular and molecular mechanisms underlying mDNA4977 formation and a detailed summary about mDNA4977 reported in various types of cancers. The current knowledges of mDNA4977 as a prognostic and predictive marker are also discussed.
  13. Effect of Ca(OH)2 dosing on thermophilic composting of anaerobic sludge to improve the NH3 recovery
    Koyama M, Nagao N, Syukri F, Yusoff FM, Toda T, Quyen TNM, et al.
    Sci Total Environ, 2019 Jun 20;670:1133-1139.
    PMID: 31018429 DOI: 10.1016/j.scitotenv.2019.03.320
    The primary biological treatment method for organic sludge is composting and/or anaerobic digestion, but their product (compost or biogas) is of little economic benefit; therefore, an improved process to produce a high-value product is required to make sludge management more sustainable. Maximizing NH3 gas recovery during composting processes has the potential benefit of producing high-value microalgal biomass. However, the majority of produced ammonia does not evaporate as NH3 gas but retains as NH4+-N in the compost after fermentation. The present study investigates the effects of the timing of Ca(OH)2 dosing (on days 2, 5, and 9), and the Ca(OH)2 dose (1.1-2.6 mmol/batch), on lab-scale thermophilic composting of anaerobic sludge. The effects on NH3 recovery, organic matter degradability, and microbial activity are evaluated. Ca(OH)2 dosing immediately improved the emission of NH3, with yields 50-69% higher than those under control conditions. The timing of the dosing did not influence NH3 recovery or organic matter degradability. Higher Ca(OH)2 doses resulted in higher NH3 recovery, while microbial activity was temporarily and marginally inhibited. The pH of the compost reached 10-11.5 but quickly dropped to 8-8.5 within a day, probably because of neutralization of Ca(OH)2 by the emitted CO2 and release of NH3, which maintained the microbial activity. The present study indicated that Ca(OH)2 dosing would be useful to apply during thermophilic composting for NH3 recovery to cultivate high-value microalgal biomass, which enables this process to obtain a more economic benefit.
  14. Fulltext Conditioned Medium of Human Menstrual Blood-Derived Endometrial Stem Cells Protects Against MPP+-Induced Cytotoxicity in vitro
    Li H, Yahaya BH, Ng WH, Yusoff NM, Lin J
    Front Mol Neurosci, 2019;12:80.
    PMID: 31024252 DOI: 10.3389/fnmol.2019.00080
    Mesenchymal stem cells (MSCs) showed the potential to treat Parkinson's disease (PD). However, it is unknown whether the conditioned medium of human menstrual blood-derived endometrial stem cells (MenSCs-CM) has the function to alleviate syndromes of PD. In this study, human neuroblastoma SH-SY5Y cells were exposed to neurotoxicant 1-methyl-4-phenylpyridinium (MPP+) for inducing a range of response characteristics of PD. After culturing this cell model with 24 h/48 h collected MenSCs-CM for different days, cell viability, pro-inflammation cytokines, mitochondrial membrane potential (ΔΨm), oxidative stress, and cell apoptosis were detected. Finally, protein assay was performed to detect 12 kinds of neurotrophic factors inside MenSCs-CM. Our results showed that MPP+ caused SH-SY5Y cell viability reduction as an increasing dose and time dependent manner. MPP+ treatment resulted in inflammation, mitochondrial dysfunction, reactive oxygen species (ROS) production accumulation, and apoptosis of SH-SY5Y at its IC50 concentration. Forty-eight hours-collected MenSCs-CM and culturing with the MPP+-treated SH-SY5Y for 2 days are the optimized condition to increase cell viability. Besides, MenSCs-CM was efficacious against MPP+ induced inflammation, ΔΨm loss, ROS generation, and it could significantly decrease cells numbers in late apoptosis stage. What's more, protein assay showed that MenSCs-CM contained various neuroprotective factors. Our study provided the first evidence that MenSCs-CM has a protective effect on MPP+-induced cytotoxicity in various aspects, and firstly showed that MenSCs can release at least 12 kinds of neurotrophic factors to medium, which may contribute to the protective function of MenSCs-CM to treat PD. This research enlightening that MenSCs-CM is beneficial in the therapy for PD and probably also for other neurodegenerative diseases.
  15. Fulltext The Impacts of Illegal Toxic Waste Dumping on Children's Health: A Review and Case Study from Pasir Gudang, Malaysia
    Ibrahim MF, Hod R, Toha HR, Mohammed Nawi A, Idris IB, Mohd Yusoff H, et al.
    Int J Environ Res Public Health, 2021 02 24;18(5).
    PMID: 33668186 DOI: 10.3390/ijerph18052221
    Poor management of hazardous waste can lead to environmental pollution, injuries, and adverse health risks. Children's exposure to hazardous waste may cause serious acute and chronic health problems due to their higher vulnerability to the toxic effects of chemicals. This study examines an incident of illegal chemical dumping in Pasir Gudang, Malaysia and its potential health impacts on children. The study introduced a risk assessment of possible health-related effects due to chemical contamination based on a real case scenario where quantification of the contamination was not feasible. A literature review and spatial analysis were used as research methods. On 6th March 2019, tons of hazardous waste were illegally disposed into Kim Kim River, Pasir Gudang, Malaysia. They were identified as benzene, acrolein, acrylonitrile, hydrogen chloride, methane, toluene, xylene, ethylbenzene, and d-limonene. As a result, 975 students in the vicinity developed signs and symptoms of respiratory disease due to the chemical poisoning. The findings of this study indicate that more effective policies and preventive actions are urgently needed to protect human health, especially children from improper hazardous waste management.
  16. Fulltext Health-Related Quality of Life and Family Functioning of Primary Caregivers of Children with Cerebral Palsy in Malaysia
    Ying K, Rostenberghe HV, Kuan G, Mohd Yusoff MHA, Ali SH, Yaacob NS
    Int J Environ Res Public Health, 2021 02 28;18(5).
    PMID: 33670850 DOI: 10.3390/ijerph18052351
    Caregiving for children with cerebral palsy (CP) has proved to negatively impact on the physical and psychological well-being of their primary caregivers. The aim of the current study was to examine the overall impact of caregiving for children with CP on the primary caregivers' health-related quality of life (HRQOL) and family functioning, and to identify potential factors associated with primary caregivers' HRQOL and family functioning. The cross-sectional study involved a total of 159 primary caregivers of children with CP with a mean age of 42.8 ± 8.4 years. Demographic data and information on the physical and leisure activities of the primary caregivers were collected, and their quality of life (QOL) was measured based on the self-reported Pediatric Quality of Life Inventory Family Impact Module (PedsQL FIM). Primary caregivers in the current study have shown good HRQOL and family functioning, with scores of 82.4 and 85.3 out of 100, respectively. Through multiple linear regression analyses, the mother's level of education, family monthly income, sleeping problems in children with CP, and the existence of children with other types of disability have been identified as factors contributing to HRQOL and family functioning. The findings help set out the course for stakeholders to establish action to enhance the QOL of primary caregivers.
  17. Neurobiology of Kratom and its main alkaloid mitragynine
    Suhaimi FW, Yusoff NH, Hassan R, Mansor SM, Navaratnam V, Müller CP, et al.
    Brain Res Bull, 2016 09;126(Pt 1):29-40.
    PMID: 27018165 DOI: 10.1016/j.brainresbull.2016.03.015
    Kratom or its main alkaloid, mitragynine is derived from the plant Mitragyna speciosa Korth which is indigenous to Southeast Asian countries. This substance has become widely available in other countries like Europe and United States due to its opium- and coca-like effects. In this article, we have reviewed available reports on mitragynine and other M. speciosa extracts. M. speciosa has been proven to have a rewarding effect and is effective in alleviating the morphine and ethanol withdrawal effects. However, studies in human revealed that prolonged consumption of this plant led to dependence and tolerance while cessation caused a series of aversive withdrawal symptoms. Findings also showed that M. speciosa extracts possess antinociceptive, anti-inflammatory, anti-depressant, and muscle relaxant properties. Available evidence further supports the adverse effects of M. speciosa preparations, mitragynine on cognition. Pharmacological activities are mainly mediated via opioid receptors as well as neuronal Ca2+ channels, expression of cAMP and CREB protein and via descending monoaminergic system. Physicochemical properties of mitragynine have been documented which may further explain the variation in pharmacological responses. In summary, current researchs on its main indole alkaloid, mitragynine suggest both therapeutic and addictive potential but further research on its molecular effects is needed.
  18. Fulltext Frontal Electroencephalogram Alpha Asymmetry during Mental Stress Related to Workplace Noise
    Alyan E, Saad NM, Kamel N, Yusoff MZ, Zakariya MA, Rahman MA, et al.
    Sensors (Basel), 2021 Mar 11;21(6).
    PMID: 33799722 DOI: 10.3390/s21061968
    This study aims to investigate the effects of workplace noise on neural activity and alpha asymmetries of the prefrontal cortex (PFC) during mental stress conditions. Workplace noise exposure is a pervasive environmental pollutant and is negatively linked to cognitive effects and selective attention. Generally, the stress theory is assumed to underlie the impact of noise on health. Evidence for the impacts of workplace noise on mental stress is lacking. Fifteen healthy volunteer subjects performed the Montreal imaging stress task in quiet and noisy workplaces while their brain activity was recorded using electroencephalography. The salivary alpha-amylase (sAA) was measured before and immediately after each tested workplace to evaluate the stress level. The results showed a decrease in alpha rhythms, or an increase in cortical activity, of the PFC for all participants at the noisy workplace. Further analysis of alpha asymmetry revealed a greater significant relative right frontal activation of the noisy workplace group at electrode pairs F4-F3 but not F8-F7. Furthermore, a significant increase in sAA activity was observed in all participants at the noisy workplace, demonstrating the presence of stress. The findings provide critical information on the effects of workplace noise-related stress that might be neglected during mental stress evaluations.
  19. Fulltext Unilateral neglect or alien hand syndrome? A diagnostic challenge
    Wan Yusoff WR, Hanafi MH, Ibrahim AH, Kassim NK, Suhaimi A
    J Taibah Univ Med Sci, 2021 Apr;16(2):288-291.
    PMID: 33897336 DOI: 10.1016/j.jtumed.2020.12.003
    Alien hand syndrome (AHS) is a rare post-stroke complication. Although the occurrence of AHS after stroke is rare, it can have a disabling impact on the lifestyle and career of the patients post stroke. It is difficult to distinguish AHS from the non-dominant hemispheric infarction with symptoms of hemianopia and left hemineglect, as patients with AHS can also have neglect as well as behaviour symptoms if the frontal lobe is involved. We report the case of a 62-year-old gentleman who was admitted to the rehabilitation ward and was treated for neglect and apraxia following right middle cerebral artery stroke. After further re-evaluation, the patient was diagnosed with AHS. Functionally, he improved and the symptoms disappeared four months after the stroke. In this case report, we highlight the features of AHS and provide a unique management approach.
  20. Optimal implementation of low impact development for urban stormwater quantity and quality control using multi-objective optimization
    Rezaei AR, Ismail Z, Niksokhan MH, Dayarian MA, Ramli AH, Yusoff S
    Environ Monit Assess, 2021 Mar 31;193(4):241.
    PMID: 33791871 DOI: 10.1007/s10661-021-09010-4
    Stormwater runoff is a major concern in urban areas which is mostly the result of vast urbanization. To reduce urban stormwater runoff and improve water quality, low impact development (LID) is used in urban areas. Therefore, it is vital to find the optimal combination of LID controls to achieve maximum reduction in both stormwater runoff and pollutants with optimal cost. In this study, a simulation-optimization model was developed by linking the EPA Storm Water Management Model (SWMM) to the Multi-Objective Particle Swarm Optimization (MOPSO) using MATLAB. The coupled model could carry out multi-objective optimization (MOO) and find potential solutions to the optimization objectives using the SWMM simulation model outputs. The SWMM model was developed using data from the BUNUS catchment in Kuala Lumpur, Malaysia. The total suspended solids (TSS) and total nitrogen (TN) were selected as pollutants to be used in the simulation model. Vegetated swale and rain garden were selected as LID controls for the study area. The LID controls were assigned to the model using the catchment characteristics. The target objectives were to minimize peak stormwater runoff, TSS, and TN with the minimum number of LID controls applications. The LID combination scenarios were also tested in SWMM to identify the best LID types and combination to achieve maximum reduction in both peak runoff and pollutants. This study found that the peak runoff, TSS, and TN were reduced by 13%, 38%, and 24%, respectively. The optimal number of LID controls that could be used at the BUNUS catchment area was also found to be 25.
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