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Small-field output ratio determination using 6 mol% Ge-doped silica fibre dosimeters

Lam SE, Noor NM, Bradley DA, Mahmud R, Pawanchek M, Abdul Rashid HA

Biomed Phys Eng Express, 2020 Nov 05;6(6).
PMID: 35042836 DOI: 10.1088/2057-1976/abc2a4

This work investigates the suitability of locally fabricated 6 mol% Ge-doped optical fibres as dosimeters for small-field output ratio measurements. Two fabrications of fibre, cylindrical (CF) and flat (FF) fibres, were used to measure doses in small photon fields, from 4 to 15 mm. The findings were compared to those of commercial Ge-doped fibre (COMM), EBT3 film and an IBA CC01 ionization chamber. Irradiations were carried out using a 6 MV SRS photon beam operating at a dose rate of 1000 cGy min-1, delivering a dose of 16 Gy. To minimise the possibility of the fibres failing to be exposed to the intended dose in small fields, the fibres were accommodated in a custom-made Perspex phantom. For the 4 mm cone the CF and FF measured output ratios were found to be smaller than obtained with EBT3 film by 32% and 13% respectively. Conversely, while for the 6 to 15 mm cone fields the FF output ratios were consistently greater than those obtained using EBT3 film, the CF output ratios differed from those of EBT3 film by at most 3.2%, at 6 mm, otherwise essentially agreeing with EBT3 values at the other field sizes. For the 4 to 7.5 mm cones, all output ratios obtained from Ge-doped optical fibre measurements were greater than those of IBA CC01 ionization chamber. The measured FF and CF output ratios for the 7.5 to 15 mm cones agreed with published MC estimates to within 15% and 13%, respectively. Down to 6 mm cone field, present measurements point to the potential of CF as a small-field dosimeter, its use recommended to be complemented by the use of EBT3 film for small-field dosimetry.
Heavy metals found in the breathing zone, toenails and lung function of welders working in an air-conditioned welding workplace

Hariri A, Mohamad Noor N, Paiman NA, Ahmad Zaidi AM, Zainal Bakri SF

Int J Occup Saf Ergon, 2018 Dec;24(4):646-651.
PMID: 28849717 DOI: 10.1080/10803548.2017.1368950

Welding operations are rarely conducted in an air-conditioned room. However, a company would set its welding operations in an air-conditioned room to maintain the humidity level needed to reduce hydrogen cracks in the specimen being welded. This study intended to assess the exposure to metal elements in the welders' breathing zone and toenail samples. Heavy metal concentration was analysed using inductively coupled plasma mass spectrometry. The lung function test was also conducted and analysed using statistical approaches. Chromium and manganese concentrations in the breathing zone exceeded the permissible exposure limit stipulated by Malaysian regulations. A similar trend was obtained in the concentration of heavy metals in the breathing zone air sampling and in the welders' toenails. Although there was no statistically significant decrease in the lung function of welders, it is suggested that exposure control through engineering and administrative approaches should be considered for workplace safety and health improvement.
Fulltext Data on RNA-seq analysis of Garcinia mangostana L. seed development

Mazlan O, Abdul-Rahman A, Goh HH, Aizat WM, Mohd Noor N

Data Brief, 2018 Feb;16:90-93.
PMID: 29188226 DOI: 10.1016/j.dib.2017.11.001

Mangosteen (Garcinia mangostana L.) has exceptional potential for commercial and pharmaceutical applications due to its delicious fruit and medicinal properties. Nevertheless, the molecular mechanism of mangosteen seed development is poorly understood. In this study, we performed transcriptomic analysis of four seed developmental stages; eight, ten, twelve and fourteen weeks after anthesis. Illumina HiSeq™ 4000 sequencer was used to generate raw data of approximately 68 Gb in size. From 451,495,326 raw reads, 406,143,756 clean reads were obtained. The raw data were uploaded to SRA database and the BioProject ID is PRJNA395504. These data provide the basis for further exploration and understanding of the molecular mechanism in mangosteen seed development.
Molecular dynamics simulation and structural analysis of aquaporin Z from an Antarctic Pseudomonas sp. strain AMS3

Balakrishnan S, Rahman RNZRA, Noor NDM, Latip W, Ali MSM

J Biomol Struct Dyn, 2023;41(21):11498-11509.
PMID: 36598349 DOI: 10.1080/07391102.2022.2164519

Aquaporin is a water channel protein that facilitates the movement of water across the cell membrane. Aquaporin from the Antarctic region has been noted for its psychrophilic properties and its ability to perform at a lower temperature but there remains limited understanding of the water mechanism of Antarctic Pseudomonas sp. strain AMS3 However, studies regarding aquaporin isolated from psychrophilic Pseudomonas sp. are still scattered. Recently, the genome sequence of an Antarctic Pseudomonas sp. strain AMS3 revealed a gene sequence encoding for a putative aquaporin designated as AqpZ1 AMS3. In this study, structure analysis and a molecular dynamics (MD) simulation of a predicted model of a fully hydrated aquaporin tetramer embedded in a lipid bilayer was performed at different temperatures for structural flexibility and stability analysis. The MD simulation results revealed that the structures were able to remain stable at low to medium temperatures. The protein was observed to have high flexibility in the loop region as compared to the helices region throughout the simulated temperatures. The selectivity filter and NPA motifs play a major role in solute selectivity and the pore radius of the protein. The structural and functional characterization of this psychrophilic aquaporin provides new insights for the future applications of this protein.Communicated by Ramaswamy H. Sarma.
The cytotoxicity effect of bismuth oxide particles synthesized hydrothermally using different reaction temperatures in vitro

Md Saad WM, Mohd Noor NA, Mohamad Salin NS, Mohd Z, Eshak Z, Abdul Razak HR

Med J Malaysia, 2024 Mar;79(Suppl 1):8-13.
PMID: 38555879

INTRODUCTION: Bismuth oxide (Bi2O3) particles gained attention in preclinical research especially in medical imaging. Bismuth oxide with its long circulation time is an alternative to the current iodine contrast media which directly possesses high X-ray attenuation coefficient. Exploration of bismuth compound is hampered owing to challenges in synthesizing control for in vivo stability.
MATERIALS AND METHODS: This study aimed are to characterize Bi2O3 particles synthesized at 60, 90 and 120 °C via hydrothermal method and investigated cytotoxicity of cell viability assay, cell morphology analysis, intracellular reactive oxygen species (ROS) assay and expression of ER stress genes by real-time PCR.
RESULTS: Results indicated that the size of rod-shaped Bi2O3 particles increased with rising synthesizing temperatures. The cytotoxicity of Bi2O3 particles in Chang liver cells was size-dependent. Bigger-sized Bi2O3 particles resulted in lesser toxicity effects. mRNA expressions of GRP78 and C/EBP homologous protein (CHOP) were down-regulated in all treated Chang liver cells due to the increasing size of Bi2O3 particles. Bi2O3 particles synthesized at 120 °C was found to be less toxic than iodine.
CONCLUSION: Data suggested that the response of Chang liver cells to Bi2O3 particle cytotoxicity has a significant relationship with its reaction temperatures. This outcome is important in hazard assessment of Bi2O3 particles as a new contrast media and provides better understanding in synthesizing control to enhance its biocompatibility.
Fulltext Induction and analysis of the alkaloid mitragynine content of a Mitragyna speciosa suspension culture system upon elicitation and precursor feeding

Mohamad Zuldin NN, Said IM, Mohd Noor N, Zainal Z, Jin Kiat C, Ismail I

ScientificWorldJournal, 2013;2013:209434.
PMID: 24065873 DOI: 10.1155/2013/209434

This study aimed to determine the effects of different concentrations and combinations of the phytohormones 2,4-dichlorophenoxy acetic acid (2,4-D), kinetin, 6-benzylaminopurine (BAP), and 1-naphthaleneacetic acid (NAA) on callus induction and to demonstrate the role of elicitors and exogenous precursors on the production of mitragynine in a Mitragyna speciosa suspension culture. The best callus induction was achieved from petiole explants cultured on WPM that was supplemented with 4 mg L⁻¹ 2,4-D (70.83%). Calli were transferred to liquid media and agitated on rotary shakers to establish Mitragyna speciosa cell suspension cultures. The optimum settled cell volume was achieved in the presence of WPM that contained 3 mg L⁻¹ 2,4-D and 3% sucrose (9.47 ± 0.4667 mL). The treatment of cultures with different concentrations of yeast extract and salicylic acid for different inoculation periods revealed that the highest mitragynine content as determined by HPLC was achieved from the culture treated with 250 mg L⁻¹ yeast extract (9.275 ± 0.082 mg L⁻¹) that was harvested on day 6 of culturing; salicylic acid showed low mitragynine content in all concentrations used. Tryptophan and loganin were used as exogenous precursors; the highest level of mitragynine production was achieved in cultures treated with 3 μM tryptophan and harvested at 6 days (13.226 ± 1.98 mg L⁻¹).
Fulltext Ficus deltoidea Jack: A Review on Its Phytochemical and Pharmacological Importance

Bunawan H, Amin NM, Bunawan SN, Baharum SN, Mohd Noor N

Evid Based Complement Alternat Med, 2014;2014:902734.
PMID: 24772185 DOI: 10.1155/2014/902734

Ficus deltoidea Jack (Moraceae) has had a long history of use in traditional medicine among the Malays to alleviate and heal ailments such as sores, wounds, and rheumatism and as an after-birth tonic and an antidiabetic drug. Modern pharmacological studies demonstrated that this plant has a wide variety of beneficial attributes for human health. Despite its importance, a review of this species has not been published in the scientific literature to date. Here, we review and summarize the historic and current literature concerning the botany, traditional uses, phytochemistry, pharmacological effects, and toxicity of this wonder plant. This summary could be beneficial for future research aiming to exploit the therapeutic potential of this useful, medicinal species.
Assessment on Inpatient Glycaemic Control in General Medical Wards, Putrajaya Hospital

Ibrahim NN, Mohd Noor N, Bahari R, Mohamed Nor L, Zainal Abidin NH

Malays J Med Sci, 2024 Apr;31(2):199-207.
PMID: 38694585 DOI: 10.21315/mjms2024.31.2.18

BACKGROUND: Inpatient hyperglycaemia is common and associated with poor outcomes such as increased mortality and prolonged hospital stay. This study aimed to determine the prevalence of inpatient hyperglycaemia and glycaemic control in Putrajaya Hospital, Malaysia. Secondary objectives were to compare the length of stay (LOS), 30-day readmission rate, and death between controlled and uncontrolled glycaemic groups.
METHODS: This cross-sectional study was conducted between 1 July and 31 December 2019 among patients in medical wards who had a blood glucose (BG) level of > 7.8 mmol/L and stayed in the wards for ≥ 24 h. We retrieved information on demographics, diabetes history and BG profiles. The definition of controlled glycaemic status is when ≥ 80% of BG readings were between 4.0 mmol/L and 10.0 mmol/L during the hospital stay.
RESULTS: The prevalence of inpatient hyperglycaemia was 55.2%. There were 841 patients who met the eligibility criteria; their mean age was 60 (13.8) years old. Most (79.4%) of the patients were Malay and 53.9% were male. There were 452 (53.7%) patients in the uncontrolled group. They were younger and admitted with more kidney complications compared to those in the controlled group. The median LOS for both groups was 3 (2) days. The uncontrolled group showed a higher percentage of readmission within 30 days (7.5% versus 4.6 %) and death during admission (3.3% versus 1.6 %) (P = 0.100 and P = 0.082).
CONCLUSION: The prevalence of inpatient hyperglycaemia was high. More than half of them had uncontrolled BG. Both groups had a similar average length of stay. The 30-day readmission rate and death during admission were higher in the uncontrolled group, although statistically not significant.
Fulltext Multi-perspectives systematic review on the applications of sentiment analysis for vaccine hesitancy

Alamoodi AH, Zaidan BB, Al-Masawa M, Taresh SM, Noman S, Ahmaro IYY, et al.

Comput Biol Med, 2021 Dec;139:104957.
PMID: 34735945 DOI: 10.1016/j.compbiomed.2021.104957

A substantial impediment to widespread Coronavirus disease (COVID-19) vaccination is vaccine hesitancy. Many researchers across scientific disciplines have presented countless studies in favor of COVID-19 vaccination, but misinformation on social media could hinder vaccination efforts and increase vaccine hesitancy. Nevertheless, studying people's perceptions on social media to understand their sentiment presents a powerful medium for researchers to identify the causes of vaccine hesitancy and therefore develop appropriate public health messages and interventions. To the best of the authors' knowledge, previous studies have presented vaccine hesitancy in specific cases or within one scientific discipline (i.e., social, medical, and technological). No previous study has presented findings via sentiment analysis for multiple scientific disciplines as follows: (1) social, (2) medical, public health, and (3) technology sciences. Therefore, this research aimed to review and analyze articles related to different vaccine hesitancy cases in the last 11 years and understand the application of sentiment analysis on the most important literature findings. Articles were systematically searched in Web of Science, Scopus, PubMed, IEEEXplore, ScienceDirect, and Ovid from January 1, 2010, to July 2021. A total of 30 articles were selected on the basis of inclusion and exclusion criteria. These articles were formed into a taxonomy of literature, along with challenges, motivations, and recommendations for social, medical, and public health and technology sciences. Significant patterns were identified, and opportunities were promoted towards the understanding of this phenomenon.
Photon irradiation response of photonic crystal fibres and flat fibres at radiation therapy doses

Hashim S, Ibrahim SA, Che Omar SS, Alajerami YS, Saripan MI, Noor NM, et al.

Appl Radiat Isot, 2014 Aug;90:258-60.
PMID: 24858954 DOI: 10.1016/j.apradiso.2014.04.016

Radiation effects of photon irradiation in pure Photonic Crystal Fibres (PCF) and Flat fibres (FF) are still much less investigated in thermoluminescense dosimetry (TLD). We have reported the TL response of PCF and FF subjected to 6 MV photon irradiation. The proposed dosimeter shows good linearity at doses ranging from 1 to 4 Gy. The small size of these detectors points to its use as a dosimeter at megavoltage energies, where better tissue-equivalence and the Bragg-Gray cavity theory prevails.
MORPHOLOGY AND MOLECULAR CHARACTERIZATION OF PSEUDO-NITZSCHIA (BACILLARIOPHYCEAE) FROM MALAYSIAN BORNEO, INCLUDING THE NEW SPECIES PSEUDO-NITZSCHIA CIRCUMPORA SP. NOV

Lim HC, Leaw CP, Su SN, Teng ST, Usup G, Mohammad-Noor N, et al.

J Phycol, 2012 Oct;48(5):1232-47.
PMID: 27011282 DOI: 10.1111/j.1529-8817.2012.01213.x

Field sampling was undertaken to investigate the occurrence of Pseudo-nitzschia Peragallo species in eight locations along the coast of Malaysian Borneo. A total of 108 strains of Pseudo-nitzschia species were isolated, and their morphology examined with SEM and TEM. Additionally, molecular data from nuclear-encoded partial LSU rDNA, and ITS regions, were characterized. A total of five species were confidently identified based on a combination of distinct morphological characteristics and supporting molecular evidence: P. brasiliana Lundholm, Hasle & Fryxell, P. cuspidata (Hasle) Hasle, P. dolorosa Lundholm & Moestrup, P. micropora Priisholm, Moestrup & Lundholm, and P. pungens (Grunow) Hasle var. pungens. However, one morphotype from Sarawak, while somewhat similar to P. caciantha, showed significant morphological distinction from this and any other of the currently described species. Most notably this morphotype possessed a characteristic pore arrangement in the poroids, with the fine pores in each perforation sector arranged in circles. Pair-wise sequence comparison of the LSU rDNA between this unidentified morphotype and P. caciantha Lundholm, Moestrup & Hasle, revealed 2.7% genetic divergence. Phylogenetic analyses strongly supported the monophyly of the morphotype. Based upon these supporting data it is here described as a new species, Pseudo-nitzschia circumpora sp. nov. A key to the six species of Pseudo-nitzschia from Malaysian Borneo is presented. Molecular signatures for all species were established based on structural comparisons of ITS2 rRNA transcripts.
Fulltext RNA-seq analysis for secondary metabolite pathway gene discovery in Polygonum minus

Loke KK, Rahnamaie-Tajadod R, Yeoh CC, Goh HH, Mohamed-Hussein ZA, Mohd Noor N, et al.

Genom Data, 2016 Mar;7:12-3.
PMID: 26981350 DOI: 10.1016/j.gdata.2015.11.003

Polygonum minus plant is rich in secondary metabolites, especially terpenoids and flavonoids. Present study generates transcriptome resource for P. minus to decipher its secondary metabolite biosynthesis pathways. Raw reads and the transcriptome assembly project have been deposited at GenBank under the accessions SRX313492 (root) and SRX669305 (leaf) respectively.
Fulltext Anaemia in type 2 diabetes mellitus (T2DM) patients in Hospital Putrajaya

Thambiah CS, Samsudin IN, George E, Ranjit LK, Saat NS, Hussein Z, et al.

Malaysian Journal of Medicine and Health Sciences, 2015;11(1):49-62.
MyJurnal

Patients with diabetes have an earlier onset and increased severity of anaemia compared to those with similar degree of renal impairment from other causes. Anaemia is associated with an increased risk of vascular complications. In this study, we determined the prevalence of anaemia in T2DM patients and its association with sociodemographic, clinical and laboratory parameters in an endocrine tertiary hospital in Malaysia. This was a cross-sectional study using retrospective electronic data from January 2011 to December 2013 of 165 T2DM patients in Hospital Putrajaya. Data was analysed using IBM SPSS Statistics version 21.0 for Windows. The prevalence of anaemia was 39.4% and majority had normocytic normochromic (80%), mild (58.5%) anaemia. Majority were Malays (73.9%), aged below 60 with comparable gender percentage and long-standing, poorly-controlled DM [median fasting blood sugar (FBS) 8mmol/L; glycated haemoglobin (HbA1c) 7.9%]. Using the KDIGO chronic kidney disease (CKD) staging system, 86% of these patients were in stages 3-5. Anaemic patients had a significantly higher serum urea, creatinine and a lower FBS, estimated glomerular filtration rate (eGFR) compared to non-anaemic patients. Anaemic patients with diabetic nephropathy had a significantly lower haemoglobin (Hb) compared to those without this complication (p=0.022). The sensitivity and specificity at a cut-off eGFR value of 38.3 ml/min/1.73 m2 (maximum Youden index = 0.462) was 66.7% and 79.5%, respectively to discriminate mild from moderate anaemia. This study shows that anaemia is already present in T2DM patients in Hospital Putrajaya at initial presentation to the specialist outpatient clinic and is significantly associated with CKD. Hence, it emphasises the obligatory need for routine and follow-up full blood count monitoring in T2DM patients in primary care as well as tertiary settings in Malaysia to enable early detection and aggressive correction of anaemia in preventing further complications.

Study site: endocrine clinic, Hospital Putrajaya
Sagittal sinus thrombosis in a patient with familial Protein C deficiency: Highlighting the impact of thrombophilia testing

Wan Ab Rahman WS, Abdullah WZ, Hassan MN, Ahmed S, Zulkafli Z, Wan Ahmed WA, et al.

Malays J Pathol, 2021 Dec;43(3):449-452.
PMID: 34958066

Plasma protein-C is a natural anticoagulant that inactivates factors Va and VIIIa. Familial protein C deficiency is inherited as an autosomal dominant disorder. The homozygous or compound heterozygous type may present early as purpura fulminant, while the heterozygous type can present as thromboembolism later in life. Presented in this report is a case of a 21-year-old female patient with protein-C deficiency, confirmed by thrombophilia investigations. She experienced recurrent deep vein thrombosis and cerebral sinus thrombosis due to thrombotic occlusion. She had a family history of deep vein thrombosis. Hence, high-risk cases should be seriously considered for long term anticoagulation therapy. The utility versus futility of thrombophilia testing in a particular situation is discussed to address and ensure safe practice among patients with thromboembolism.
Fulltext Relationship between dyslipidaemia and glycaemic status in patients with Type 2 diabetes mellitus

Thambiah SC, Samsudin IN, George E, Zahari Sham SY, Lee HM, Muhamad MA, et al.

Malays J Pathol, 2016 Aug;38(2):123-30.
PMID: 27568669 MyJurnal

The risk of coronary heart disease (CHD) is dramatically increased in diabetic patients due to their atherogenic lipid profile. The severity of CHD in diabetic patients has been found to be directly associated with glycated haemoglobin (HbA1c). According to the Malaysian Clinical Practice Guidelines on diabetes mellitus (DM), HbA1c level less than 6.5% reduces the risk of microvascular and macrovascular complications. Hence, this study aimed to determine the relationship between dyslipidaemia and glycaemic status in patients with type 2 DM (T2DM) patients in Hospital Putrajaya, a tertiary endocrine centre in Malaysia. This was a cross sectional, retrospective study of 214 T2DM patients with dyslipidaemia who had visited the endocrine clinic between January 2009 and December 2012. Significant correlations were found between fasting blood glucose (FBG) and HbA1c with total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL), non-high density lipoprotein cholesterol (non-HDL), LDL/HDL ratio and TC/HDL ratio; greater correlation being with HbA1c than FBG. In patients with HbA1c ≥ 6.5%, TC, TG, non-HDL and TC/HDL ratio were significantly higher than in patients with HbA1c < 6.5%. Non-HDL, LDL/HDL ratio, TC/HDL ratio and HbA1c were significantly lower in patients on statin treatment than nontreated patients (p<0.05). This significant association between glycaemic status and dyslipidaemia emphasises the additional possible use of HbA1c as a biomarker for dyslipidaemia as well as a potential indirect predictor of cardiovascular disease (CVD) risk in T2DM patients.
Anti-Tumor Necrosis Factor for Supplementary Management in Severe Asthma: A Systematic Review and Meta-analysis

Ahmad S, Mohd Noor N, Engku Nur Syafirah EAR, Irekeola AA, Shueb RH, Chan YY, et al.

J Interferon Cytokine Res, 2023 Feb;43(2):77-85.
PMID: 36795972 DOI: 10.1089/jir.2022.0211

Tumor-necrosis factor (TNF) is recognized as a therapeutic target in inflammatory diseases, including asthma. In severe forms of asthma, biologics such as anti-TNF are rendered to be investigated as therapeutic options in severe asthma. Hence, this work is done to assess the efficacy and safety of anti-TNF as a supplementary therapy for patients with severe asthma. A systematic search of 3 databases (Cochrane Central Register of Controlled Trials, MEDLINE, ClinicalTrials.gov) was performed to identify for published and unpublished randomized controlled trials comparing anti-TNF (etanercept, adalimumab, infliximab, certolizumab pegol, golimumab) with placebo in patients diagnosed with persistent or severe asthma. Random-effects model was used to estimate risk ratios and mean differences (MDs) with confidence intervals (95% CIs). PROSPERO registration number is CRD42020172006. Four trials with 489 randomized patients were included. Comparison between etanercept and placebo involved 3 trials while comparison between golimumab and placebo involved 1 trial. Etanercept produced a small but significant impairment in forced expiratory flow in 1 second (MD 0.33, 95% CI 0.09-0.57, I2 statistic = 0%, P = 0.008) and a modest improvement of asthma control using the Asthma Control Questionnaire. However, using the Asthma Quality of Life Questionnaire, the patients exhibit an impaired quality of life with etanercept. Treatment with etanercept showed a reduced injection site reaction and gastroenteritis compared with placebo. Although treatment with anti-TNF is shown to improve asthma control, severe asthma patients did not benefit from this therapy as there is limited evidence for improvement in lung function and reduction of asthma exacerbation. Hence, it is unlikely to prescribe anti-TNF in adults with severe asthma.
First Report of Leaf Spot of Pineapple (Ananas comosus (L.) Merr Caused by Neoscytalidium dimidiatum in Malaysia

Afifah M, Sapak Z, Mohd Noor N, Ab Wahab MZ, Mohd Anuar IS, Ramli NW, et al.

Plant Dis, 2024 Jan 22.
PMID: 38254324 DOI: 10.1094/PDIS-09-23-1796-PDN

In June 2017, severe leaf spots symptoms were observed by growers on pineapple leaves of Josapine variety in in Alor Pongsu (5°01'60.00" N, 100°34' 59.99" E), Perak, northwest of Peninsular Malaysia. The early infection stage shows that several brown spots could be observed, which then would merge to form large brown to creamy white lesions that cover all the leaf surface. This infection finally caused the plant to die after a while. Disease observations conducted from 2018 - 2023 showed that 10-15% incidences of the disease were observed in several pineapple farms located in Johor, Kedah, and Sarawak. The aim of this study to confirm the causal pathogen of the disease by performing isolation, pathogenicity testing, and identification of the primary causal pathogen from 20 samples of infected leaves collected from Alor Pongsu. The leaf tissues between infected and healthy were cut into small pieces (0.5 cm 0.5 cm), and surface sterilized with 1% sodium hypochlorite for 30 seconds, followed by 70% ethanol for 30 seconds, and rinsed thrice with sterilized water before placing on Potato Dextrose Agar (PDA). The PDA plates were incubated at room temperature (28 ± 2℃) in natural light. After five days of incubation, the potential causal pathogen was purified using a single conidial isolation technique for morphological and molecular characterizations. All 32 isolates displayed similar phenotypes. Based on morphological observation on PDA, the colonies were initially white of aerial mycelia but gradually darkened as the culture aged. Microscopic features of the 14-day-old fungal culture showed that the mycelia were branched with 0- 1 septa, pigmented, and brown. Arthroconidia were ellipsoid to ovoid or round shaped, hyaline, with rounded apex, truncate base, and occurring singly or in chains averaging 9 ± 3 × 5 ± 2 μm (n = 20). Based on the morphological characteristics, the fungal isolates were tentatively identified as Neoscytalidium species. A representative isolate of Neoscytalidium coded as UiTMPMD2 was further identified through PCR implication of the internal transcribed spacer (ITS) region using ITS1 and ITS4 primers and BLAST homology search as Neoscytalidium dimidiatum (Penz.) Crous & Slippers based on 100% similarity (575 bp out of 575 bp) to a reference sequence (accession no. KU204558.1). The sequence was deposited in Gen Bank (accession no. OR366479) with reference sequence code of INBio:30A. Pathogenicity tests were performed on 10 whole plants of Josapine pineapple (4 months old) using a leaf inoculating method (Wu et al. 2022) in a glasshouse (25-32°C) and repeated twice. Four mature leaves per each plant were wounded at two points and inoculated with mycelium PDA plugs from 7-days-old cultures of N. dimidiatum. Control plants were wounded in the same manner but inoculated with sterilized PDA plugs. Seven days post inoculation, leaf spot symptoms were observed on treated plants with the pathogen, while the control plants remained symptomless. Pathogen was successfully reisolated from brown leaf spot symptoms in which the cultural and morphological characteristics were identical to those of the originals. Neoscytalidium dimidiatum has a wide range of hosts and it has been reported in Malaysia to cause stem canker on pitahaya (Mohd et al. 2003; Khoo et al. 2023 ) and fruit rot of guava (Ismail et al. 2021). To the best of our knowledge this is the first report of N. dimidiatum causing leaf spots on pineapples in Malaysia. This report establishes a foundation for further study of N. dimidiatum that can effectively address the disease in pineapple.
Fulltext From the Front or Back Door? Quantitative analysis of direct and indirect extractions of α-mangostin from mangosteen (Garcinia mangostana)

Eukun Sage E, Jailani N, Md Taib AZ, Mohd Noor N, Mohd Said MI, Abu Bakar M, et al.

PLoS One, 2018;13(10):e0205753.
PMID: 30321238 DOI: 10.1371/journal.pone.0205753

The pulp and pericarp of mangosteen (Garcinia mangostana) fruit are popular food, beverage and health products whereby 60% of the fruit consist of the pericarp. The major metabolite in the previously neglected or less economically significant part of the fruit, the pericarp, is the prenylated xanthone α-mangostin. This highly bioactive secondary metabolite is typically isolated using solvent extraction methods that involve large volumes of halogenated solvents either via direct or indirect extraction. In this study, we compared the quantities of α-mangostin extracted using three different extraction methods based on the environmentally friendly solvents methanol and ethyl acetate. The three solvent extractions methods used were direct extractions from methanol (DM) and ethyl acetate (DEA) as well as indirect extraction of ethyl acetate obtained via solvent partitioning from an initial methanol extract (IEA). Our results showed that direct extraction afforded similar and higher quantities of α-mangostin than indirect extraction (DM: 318 mg; DEA: 305 mg; IEA: 209 mg per 5 g total dried pericarp). Therefore, we suggest that the commonly used method of indirect solvent extraction using halogenated solvents for the isolation of α-mangostin is replaced by single solvent direct extraction using the environmentally friendly solvents methanol or ethyl acetate.
Fulltext Transcriptome analysis of Polygonum minus reveals candidate genes involved in important secondary metabolic pathways of phenylpropanoids and flavonoids

Loke KK, Rahnamaie-Tajadod R, Yeoh CC, Goh HH, Mohamed-Hussein ZA, Zainal Z, et al.

PeerJ, 2017;5:e2938.
PMID: 28265493 DOI: 10.7717/peerj.2938

BACKGROUND: Polygonum minus is an herbal plant in the Polygonaceae family which is rich in ethnomedicinal plants. The chemical composition and characteristic pungent fragrance of Polygonum minus have been extensively studied due to its culinary and medicinal properties. There are only a few transcriptome sequences available for species from this important family of medicinal plants. The limited genetic information from the public expressed sequences tag (EST) library hinders further study on molecular mechanisms underlying secondary metabolite production.
METHODS: In this study, we performed a hybrid assembly of 454 and Illumina sequencing reads from Polygonum minus root and leaf tissues, respectively, to generate a combined transcriptome library as a reference.
RESULTS: A total of 34.37 million filtered and normalized reads were assembled into 188,735 transcripts with a total length of 136.67 Mbp. We performed a similarity search against all the publicly available genome sequences and found similarity matches for 163,200 (86.5%) of Polygonum minus transcripts, largely from Arabidopsis thaliana (58.9%). Transcript abundance in the leaf and root tissues were estimated and validated through RT-qPCR of seven selected transcripts involved in the biosynthesis of phenylpropanoids and flavonoids. All the transcripts were annotated against KEGG pathways to profile transcripts related to the biosynthesis of secondary metabolites.
DISCUSSION: This comprehensive transcriptome profile will serve as a useful sequence resource for molecular genetics and evolutionary research on secondary metabolite biosynthesis in Polygonaceae family. Transcriptome assembly of Polygonum minus can be accessed at http://prims.researchfrontier.org/index.php/dataset/transcriptome.
Fulltext Translation and trans-cultural adaptation to the Malay version of the COVID-19 vaccine hesitancy questionnaire among healthcare workers in Malaysia

Zaid SNA, Abdul Kadir A, Mohd Noor N, Ahmad B, Yusoff MSB, Ramli AS, et al.

PLoS One, 2024;19(4):e0302237.
PMID: 38630657 DOI: 10.1371/journal.pone.0302237

INTRODUCTION: Healthcare workers play a crucial role in supporting COVID-19 vaccination as they are the most trusted source of information to the public population. Assessing the healthcare workers' hesitancy towards COVID-19 vaccination is pertinent, however, there are limited validated tools to measure their hesitancy on COVID-19 vaccines. This study aims to adapt and validate the first COVID-19 hesitancy scale among healthcare workers in Malaysia.
MATERIALS AND METHODS: This study adapted and translated the Vaccine Hesitancy Scale (VHS) developed by the WHO SAGE Working Group. The scale underwent a sequential validation process, including back-back translation, content, face, and construct validity for Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA). The reliability was tested using internal consistency (Cronbach's alpha composite reliability (CR) and average variance extracted (AVE)).
RESULTS: The data for EFA and CFA were completed by a separate sample of 125 and 300 HCWs, respectively. The EFA analysis of the C19-VHS-M scale was unidimensional with 10 items. A further CFA analysis revealed a uniform set of nine items with acceptable goodness fit indices (comparative fit index = 0.997, Tucker-Lewis index = 0.995, incremental fit index = 0.997, chi-squared/degree of freedom = 1.352, and root mean square error of approximation = 0.034). The Cronbach's alpha, CR and AVE results were 0.953, 0.95 and 0.70, respectively.
CONCLUSIONS: The questionnaire was valid and reliable for use in the Malay language.

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