Displaying publications 81 - 100 of 254 in total

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  1. Fulltext Residence time distribution (RTD) in operating plant:a review
    Noraishah Othman, Nor Pa’iza Mohamad Hasan, Nazrul Hizam Yusoff, Mohd Amirul Syafiq Mohd Yunos, Engku Mohd Fahmi Engku Chik
    Jurnal Sains Nuklear Malaysia, 2016;28(2):30-36.
    MyJurnal
    Radiotracer technology is a technique of radioactive injection into the systemand the detection is done using radiationdetector.It is alsoa tool for investigating and solving plant process problems namely process malfunctions andmechanical damages. Radiotracer is the most preferred stimulus response techniques in the industries due to its non-invasive application and on line monitoring capabilities, which avoid shut down of the plant. Radiotracer techniques have many advantages, such as high detection sensitivity, in-situ detection, availability of a wide range of compatible radiotracers for different phases, rapid response and high reliability and accuracy of the results. The residence time distribution (RTD) is one of the important parameters that can provide information on the characteristics or hydrodynamics of the nuclear reactor. In this paper, the overall review is presented in brief regarding radiotracer technology in plant operation.
  2. Fulltext The evaluation of mass attenuation coefficients of water equivalent phantom materials and Rhizophora spp. particleboards by using compton scattering method
    Mohd Fahmi Mohd Yusof, Puteri Nor Khatijah Abd Hamid, Abdul Aziz Tajuddin, Rokiah Hashim, Norriza Mohd Isa
    Jurnal Sains Nuklear Malaysia, 2018;30(1):1-7.
    MyJurnal
    The mass attenuation coefficients of solid water phantoms, Perspex® phantoms and Rhizophora spp. particleboards were determined by using Compton scattering technique measured using Ludlum configuration. The gamma energy of 137Cs sealed source were measured at 30°, 45°, 60° and 75° angles providing scattered gamma energies between 337.72 and 564.09 keV. The mass attenuation coefficients of solid water and fabricated Rhizophora spp. particleboards were the nearest to XCOM values of water with average percentage of discrepancies of 6.8% and 5.9%, respectively. The results indicated similar attenuation properties of solid water and fabricated Rhizophora spp. particleboards and the suitability of the Ludlum configuration to determine the mass attenuation coefficient of materials using Compton scatter technique.
  3. Fulltext Lipoma Arborescens of the knee: a case report of rare entity
    Ikmal Hisyam Bakrin, Hasni Mahayidin, Khairul Shakir Ab Rahman, Wan Irnawati Wan Ab Rahman, Sazali Satari, Asrul Fahmi Azizan
    Malaysian Journal of Medicine and Health Sciences, 2018;14(3):60-63.
    MyJurnal
    Lipoma arborescens is a non-neoplastic, reactive condition due to chronic synovial inflammation and irritation, characterized by frond-like or villous proliferation of mature adipose tissue covered by hyperplastic synovium. The knee is the most commonly affected site particularly the suprapatellar pouch. We report a case of lipoma arborescens affecting the right knee of an elderly Chinese gentleman associated with bilateral knee and hand osteoarthritis. He presented with progressive worsening of right knee swelling and pain. Partial synovectomy of the right knee was performed and no lesion recurrence was noted at one year post-operation. The clinical and imaging findings, pathological features, together with differential diagnoses were discussed.
  4. Decolorization and Mineralization of Batik Wastewater through Solar Photocatalytic Process
    Wan Fadhilah Khalik, Ong SA, Wong YS, Nik Athirah Yusoff, Fahmi Ridwan, Ho LN
    Sains Malaysiana, 2015;44:607-612.
    In this study, the photocatalytic degradation of batik wastewater in the presence of zinc oxide (ZnO) as photocatalyst was
    investigated. The effect of various operating parameters, such as pH of batik wastewater, catalyst dosage and aeration
    on the photocatalytic degradation process, was examined. The mineralization of batik wastewater was also evaluated
    through chemical oxygen demand analysis. The decolorization of batik wastewater was enhanced at acidic conditions
    (pH3) which was 88.2% after 10 h irradiated under solar light, meanwhile its mineralization was 286 mg/L after 12 h
    irradiation time. The data obtained for photocatalytic degradation of batik wastewater was well fitted with the LangmuirHinshelwood
    kinetic model. It can be concluded that batik wastewater could be decolorized and mineralized under solar
    light irradiation with presence of ZnO.
  5. Fulltext Emergency thoracotomy and major lung resection for penetrating chest trauma: Lessons learnt from a review of three cases
    Sachithanandan A, Fahmi PA, Faisal I, Badmanaban B, Abdul Muis J, Mohd Arif MN
    Med J Malaysia, 2013 Jun;68(3):227-30.
    PMID: 23749011 MyJurnal
    Emergency lung resection for chest trauma is a rare event with a reported incidence of 0.08-1.3% but is associated with a high morbidity and mortality especially if a pneumonectomy is required, if due to blunt chest trauma or when concomitant injuries are present. We report three cases of young adult males with penetrating chest injuries that required emergency thoracotomy (ET) and anatomical lung resection to achieve definitive control of life threatening pulmonary haemorrhage. All patients survived to hospital discharge and remained well on follow-up. Indications for an ET and what constitutes the optimal operative management of such patients is discussed.
  6. Fulltext How deep is deep enough? Analysis of sea turtle eggs nest relocation procedure at Chagar Hutang Turtle Sanctuary
    Najwa-Sawawi S, Azman NM, Rusli MU, Ahmad A, Fahmi-Ahmad M, Fadzly N
    Saudi J Biol Sci, 2021 Sep;28(9):5053-5060.
    PMID: 34466082 DOI: 10.1016/j.sjbs.2021.05.021
    Sea turtle eggs incubation involves natural and artificial incubation of eggs, and indeed the depth will be varied and presumably affect the development of hatchlings. For nest relocation, the researcher needs to decide on the depth to incubate the eggs. Sea turtle eggs clutches may vary between 40 and 120 eggs for the green turtle, thus using a single value as the standard procedure might affect the quality of hatchlings. Here we quantify the dimension of the natural (in-situ) nest constructed by the nester and the artificial (ex-situ) built by our ranger during nest relocation. We suggest a linear regression calculation of Y = 0.2366X + 59.3267, better predict a more accurate nest depth based on the number of eggs to imitate the natural nest.
  7. The antifungal agent of silver nanoparticles activated by diode laser as light source to reduce C. albicans biofilms: an in vitro study
    Astuti SD, Puspita PS, Putra AP, Zaidan AH, Fahmi MZ, Syahrom A, et al.
    Lasers Med Sci, 2019 Jul;34(5):929-937.
    PMID: 30413898 DOI: 10.1007/s10103-018-2677-4
    Candida albicans is a normal flora caused fungal infections and has the ability to form biofilms. The aim of this study was to improve the antifungal effect of silver nanoparticles (AgNPs) and the light source for reducing the biofilm survival of C. albicans. AgNPs were prepared by silver nitrate (AgNO3) and trisodium citrate (Na3C6H5O7). To determine the antifungal effect of treatments on C. albicans biofilm, samples were distributed into four groups; L + P+ was treatment with laser irradiation and AgNPs; L + P- was treatment with laser irradiation only; L - P+ was treatment with AgNPs only (control positive); L - P- was no treatment with laser irradiation or AgNPs (control negative). The growth of fungi had been monitored by measuring the optical density at 405 nm with ELISA reader. The particle size of AgNPs was measured by using (particle size analyzer) and the zeta potential of AgNPs was measured by using Malvern zetasizer. The PSA test showed that the particle size of AgNPs was distributed between 7.531-5559.644 nm. The zeta potentials were found lower than - 30 mV with pH of 7, 9 or 11. The reduction percentage was analyzed by ANOVA test. The highest reduction difference was given at a lower level irradiation because irradiation with a density energy of 6.13 ± 0.002 J/cm2 resulted in the biofilm reduction of 7.07 ± 0.23% for the sample without AgNPs compared to the sample with AgNPs that increased the biofilm reduction of 64.48 ± 0.07%. The irradiation with a 450-nm light source had a significant fungicidal effect on C. albicans biofilm. The combination of light source and AgNPs provides an increase of biofilm reduction compared to the light source itself.
  8. Fulltext Consequences of Circadian Disruption in Shift Workers on Chrononutrition and their Psychosocial Well-Being
    Mohd Azmi NAS, Juliana N, Mohd Fahmi Teng NI, Azmani S, Das S, Effendy N
    Int J Environ Res Public Health, 2020 03 19;17(6).
    PMID: 32204445 DOI: 10.3390/ijerph17062043
    The workers and employees in various institutions are subjected to different shifts and work schedules. The employees work not only at daytime but also during odd hours at night. The biological clock of an individual is often altered during night shifts. This affects the psychosocial well-being and circadian nutritional intake of the worker. Disturbance in circadian rhythm results in the development of metabolic disorders such as hypertension, dyslipidemia, dysglycemia, and abdominal obesity. In the present review, we discuss the nature of shift work, sleep/wake cycle of an individual, chrononutrition, dietary habits, and meal changes with regard to timing and frequency, related to shift work. We also discuss the relationship between nutritional intake and psychosocial well-being among shift workers. The review may be beneficial for prevention of metabolic disorders and maintaining sound psychological condition in shift workers.
  9. Fulltext Determinants of early postpartum psychological reaction among mothers in Kuala Lumpur Hospital
    Ramli M, Abdullah AAW, Saiful MIB, Fafiz MN, Fahmi AAZ
    International Medical Journal Malaysia, 2010;9(1):37-41.
    MyJurnal
    Introduction: Maternal psychological well-being determines early mother-infant relationship and babys health. Paying attention on this aspect is essential particularly in early postpartum period. This study aimed to determine early psychological reactions toward socioeconomic profi les, delivery methods and delivery outcomes among postpartum mothers in Kuala Lumpur Hospital. Materials and Methods: A total of 150 two week-postpartum mothers participated in this cross sectional study and their psychological perspective was measured by using the Depressive, Anxiety and Stress Scale (DASS). Results: 4%, 16% and 4.7% of respondents had significant depressive, anxiety and stress levels respectively. Conclusion: Socioeconomic variables such household income, level of education and presence of medical illness were statistically signifi cant to determine early postpartum psychological reactions but not the modes or outcomes of delivery.
  10. Fulltext Intraoperative cerebral oximetry in open heart surgeries reduced postoperative complications: A retrospective study
    Juliana N, Abu Yazit NA, Kadiman S, Muhammad Hafidz K, Azmani S, Mohd Fahmi Teng NI, et al.
    PLoS One, 2021;16(5):e0251157.
    PMID: 34038405 DOI: 10.1371/journal.pone.0251157
    Cardiothoracic surgeries are life-saving procedures but often it results in various complications. Intraoperative cerebral oximetry monitoring used to detect regional cerebral oxygen saturation (rScO2) is a non-invasive method that provides prognostic importance in cardiac surgery. The main aim of the present study was to evaluate the association of intraoperative cerebral oxygen monitoring during cardiac surgery on postoperative complications. This was a case-controlled retrospective study conducted on adult patients, who underwent open-heart surgery in National Heart Institute, Malaysia. The case group comprised patients on protocolized cerebral oximetry monitoring. They were treated using a standardized algorithm to maintain rScO2 not lower than 20% of baseline rScO2. The control group comprised patients with matched demographic background, preoperative risk factors, and type of surgical procedures. Propensity score stratification was utilized to contend with selection bias. Retrospective analysis was performed on 240 patients (case group) while comparing it to 407 patients (control group). The non-availability of cerebral oximetry monitoring during surgery was the prominent predictor for all outcome of complications; stroke (OR: 7.66), renal failure needing dialysis (OR: 5.12) and mortality (OR: 20.51). Postoperative complications revealed that there were significant differences for risk of mortality (p<0.001, OR = 20.51), renal failure that required dialysis (p<0.001, OR = 5.12) and stroke (p <0.05, OR = 7.66). Protocolized cerebral oximetry monitoring during cardiothoracic surgeries was found to be associated with lower incidence of stroke, renal failure requiring dialysis and mortality rate.
  11. Fulltext Review of Functional Aspects of Nanocellulose-Based Pickering Emulsifier for Non-Toxic Application and Its Colloid Stabilization Mechanism
    Teo SH, Chee CY, Fahmi MZ, Wibawa Sakti SC, Lee HV
    Molecules, 2022 Oct 23;27(21).
    PMID: 36363998 DOI: 10.3390/molecules27217170
    In the past few years, the research on particle-stabilized emulsion (Pickering emulsion) has mainly focused on the usage of inorganic particles with well-defined shapes, narrow size distributions, and chemical tunability of the surfaces such as silica, alumina, and clay. However, the presence of incompatibility of some inorganic particles that are non-safe to humans and the ecosystem and their poor sustainability has led to a shift towards the development of materials of biological origin. For this reason, nano-dimensional cellulose (nanocellulose) derived from natural plants is suitable for use as a Pickering material for liquid interface stabilization for various non-toxic product formulations (e.g., the food and beverage, cosmetic, personal care, hygiene, pharmaceutical, and biomedical fields). However, the current understanding of nanocellulose-stabilized Pickering emulsion still lacks consistency in terms of the structural, self-assembly, and physio-chemical properties of nanocellulose towards the stabilization between liquid and oil interfaces. Thus, this review aims to provide a comprehensive study of the behavior of nanocellulose-based particles and their ability as a Pickering functionality to stabilize emulsion droplets. Extensive discussion on the characteristics of nanocelluloses, morphology, and preparation methods that can potentially be applied as Pickering emulsifiers in a different range of emulsions is provided. Nanocellulose's surface modification for the purpose of altering its characteristics and provoking multifunctional roles for high-grade non-toxic applications is discussed. Subsequently, the water-oil stabilization mechanism and the criteria for effective emulsion stabilization are summarized in this review. Lastly, we discuss the toxicity profile and risk assessment guidelines for the whole life cycle of nanocellulose from the fresh feedstock to the end-life of the product.
  12. Fulltext In Vitro Assessment on Designing Novel Antibiofilms of Pseudomonas aeruginosa Using a Computational Approach
    Rachmawati D, Fahmi MZ, Abdjan MI, Wasito EB, Siswanto I, Mazlan N, et al.
    Molecules, 2022 Dec 15;27(24).
    PMID: 36558064 DOI: 10.3390/molecules27248935
    An anti-biofilm that can inhibit the matrix of biofilm formation is necessary to prevent recurrent and chronic Pseudomonas aeruginosa infection. This study aimed to design compounds with a new mechanism through competitive inhibitory activity against phosphomannomutase/phosphoglucomutase (PMM/PGM), using in vitro assessment and a computational (in silico) approach. The active site of PMM/PGM was assessed through molecular redocking using L-tartaric acid as the native ligand and other small molecules, such as glucaric acid, D-sorbitol, and ascorbic acid. The docking program set the small molecules to the active site, showing a stable complex formation. Analysis of structural similarity, bioavailability, absorption, distribution, metabolism, excretion, and toxicity properties proved the potential application of ligands as an anti-biofilm. In vitro assessment with crystal violet showed that the ligands could reach up to 95.87% inhibition at different concentrations. The nitrocellulose membrane and scanning electron microscopic visualization showed that the untreated P. aeruginosa biofilm was denser than the ligand-treated biofilm.
  13. Fulltext Effect of ocean acidification on the growth, response and hydrocarbon degradation of coccolithophore-bacterial communities exposed to crude oil
    Fahmi AM, Summers S, Jones M, Bowler B, Hennige S, Gutierrez T
    Sci Rep, 2023 Mar 27;13(1):5013.
    PMID: 36973465 DOI: 10.1038/s41598-023-31784-5
    Hydrocarbon-degrading bacteria, which can be found living with eukaryotic phytoplankton, play a pivotal role in the fate of oil spillage to the marine environment. Considering the susceptibility of calcium carbonate-bearing phytoplankton under future ocean acidification conditions and their oil-degrading communities to oil exposure under such conditions, we investigated the response of non-axenic E. huxleyi to crude oil under ambient versus elevated CO2 concentrations. Under elevated CO2 conditions, exposure to crude oil resulted in the immediate decline of E. huxleyi, with concomitant shifts in the relative abundance of Alphaproteobacteria and Gammaproteobacteria. Survival of E. huxleyi under ambient conditions following oil enrichment was likely facilitated by enrichment of oil-degraders Methylobacterium and Sphingomonas, while the increase in relative abundance of Marinobacter and unclassified Gammaproteobacteria may have increased competitive pressure with E. huxleyi for micronutrient acquisition. Biodegradation of the oil was not affected by elevated CO2 despite a shift in relative abundance of known and putative hydrocarbon degraders. While ocean acidification does not appear to affect microbial degradation of crude oil, elevated mortality responses of E. huxleyi and shifts in the bacterial community illustrates the complexity of microalgal-bacterial interactions and highlights the need to factor these into future ecosystem recovery projections.
  14. Bio-based Pickering emulsifier from mangosteen residues-derived sodium caseinate grafted spherical cellulose nanocrystals: Stability, rheological properties and microstructure studies
    Yahya M, Sakti SCW, Fahmi MZ, Chuah CH, Lee HV
    Int J Biol Macromol, 2024 Feb;257(Pt 2):128696.
    PMID: 38072349 DOI: 10.1016/j.ijbiomac.2023.128696
    This study focuses on the preparation of mangosteen rind-derived nanocellulose via green ascorbic acid hydrolysis. Subsequently, milk protein-grafted nanocellulose particles were developed as a renewable Pickering emulsifier for water-oil stabilization. The stabilizing efficiency of modified nanocellulose (NC-S) at different caseinate (milk protein) concentrations (1.5, 3.0, and 4.0 % w/v) was tested in a water-in-oil emulsion (W/O ratio of 40:60). At a concentration 3.0 % w/v of caseinate (3.0NC-S), the emulsion exhibited a stronger network of adsorption between water, Pickering emulsifier, and oil. This resulted in reduced oil droplet flocculation, increased stability over a longer period, and favorable emulsifying properties, as depicted in the creaming index profile, oil droplet distribution, and rheology analysis. Since 3.0NC-S demonstrated the best colloidal stability, further focus will be placed on its microstructural properties, comparing them with those of mangosteen rind (MG), cellulose, and nanocellulose (NC-L). The XRD profile indicated that both NC-L and NC-S possessed a cellulose nanocrystal structure characterized as type I beta with a high crystallinity index above 60 %. Morphology investigation shown that the NC-L present in the spherical shape of particles with nanosized ranging at diameters of 11.27 ± 0.50 nm and length 11.76 ± 0.46 nm, while modified NC-S showed increase sized at 14.26 ± 4.60 nm and length 14.96 ± 4.94 nm. The increment of particle sizes from NC-L to NC-S indicated 2.82 × 10-15 mg/m2 of surface protein coverage by caseinate functional groups.
  15. A Red Flag: A Case of Oropharyngeal Cancer Masquerading as an Ulcer of an Infective Origin
    Habib Rahman AF, Ahmad Fahmi AK, Ahmad Tarmizi NE, Hui Heng C, Mohan Singh AS
    Cureus, 2023 Dec;15(12):e50411.
    PMID: 38213374 DOI: 10.7759/cureus.50411
    Oropharyngeal squamous cell carcinoma is a prevalent neoplastic condition. The incidence rate in Malaysia is rising, with human papillomavirus (HPV) infection being recognized as a significant contributing factor. Hence, it is paramount for physicians to effectively diagnose and identify significant indicators that may indicate a malignant etiology. In this study, we present a case of a middle-aged Malay male who presented with the primary symptom of persistent right throat discomfort for one month. The preliminary presentation, blood parameters, and initial histopathological examination (HPE) findings indicate the presence of an infection. However, despite undergoing several medical treatments, the patient's symptoms remain, albeit with only minor clinical improvement. Subsequently, the patient underwent a biopsy under general anesthesia, which subsequently yielded a report indicating the presence of oropharyngeal squamous cell carcinoma with a negative p16 status. Therefore, it is imperative for clinicians to possess knowledge of warning flags and exercise vigilance when encountering a patient who fails to respond despite thorough and precise evaluation. If there is a strong suspicion of malignancy, it is imperative to do a comprehensive clinical investigation and regular monitoring.
  16. Fulltext Freshwater fishes (Actinopterygii) of Kenyir Reservoir, Peninsular Malaysia: Updated checklist, taxonomic concerns and alien species
    Aqmal-Naser M, Ali NA, Azmi NU, Fahmi-Ahmad M, Rizal SA, Ahmad AB
    Biodivers Data J, 2023;11:e100337.
    PMID: 38327369 DOI: 10.3897/BDJ.11.e100337
    BACKGROUND: A total of 87 freshwater fish species from 30 families were recorded from the Kenyir Reservoir, Peninsular Malaysia, where 75 are native and 12 are introduced species. Few species still have unstable taxonomy identities which urge further studies. Most of the species were categorised as Least Concern (LC) and two were threatened species; Endangered and Critically Endangered (EN and CR). One introduced species, Gambusiaaffinis is widespread in the human-associated area, while other introduced fish species can be considered low in numbers.

    NEW INFORMATION: Twenty five fish species are recorded for the first time in the Kenyir Reservoir.

  17. Chrononutrition behaviors, sugar-sweetened beverage consumption, sleep quality and the association with body mass index among Malaysian women
    Mohd Fahmi Teng NI, Norsham J, Nadhra A, Dalila A, Nursyafiqa, Nasuha SI, et al.
    Chronobiol Int, 2023 Nov 02;40(11):1487-1499.
    PMID: 37885231 DOI: 10.1080/07420528.2023.2267679
    The present study aimed to determine the association between chrononutrition behaviors, sugar-sweetened beverage intake, and sleep quality among Malaysian women. A cross-sectional study using a validated, self-administered Chrononutrition Profile Questionnaire, Beverage Questionnaire and Sleep Quality Index were conducted among 934 Malaysian women. Multinomial logistic regression was performed to obtain odds ratios of being overweight/underweight and to test the association with poor sleep quality. 40% of Malaysian women were either overweight or obese and 65.4% had poor sleep quality. We found that breakfast skipping (OR: 4.101; CI: 2.378-7.070), poor evening eating (OR: 4.073; CI: 1.631-10.186), and eating the largest meal at night (OR: 6.970; CI: 1.944-24.994) increased the odds of being underweight. On the other hand, the daily consumption of 100% fruit juices (OR: 1.668; CI: 1.058-1.731), daily consumption of sweetened coffee or tea (OR: 1.707; CI: 1.162-2.508) and consumption of diet soft drinks by 6 times or fewer (OR: 1.484; CI: 1.066-2.064) are associated with increased odds of being overweight. However, when adjusted, only poor evening latency (AOR: 16.638; CI: 1.986-139.383) revealed an increased odd of being underweight. The highest odds predicting poor sleep quality were found for eating the largest meal during dinner (OR: 3.696; CI: 1.967-6.945) and (AOR: 2.194; CI: 1.119-4.304) when adjusted. Hence, the result indicates that multifactorial impacts on women's body weight and recommendations to adjust chrononutrition and sugar-sweetened beverages intake in lifestyle must be done carefully considering other parameters together.
  18. Fulltext Cortisol on Circadian Rhythm and Its Effect on Cardiovascular System
    Mohd Azmi NAS, Juliana N, Azmani S, Mohd Effendy N, Abu IF, Mohd Fahmi Teng NI, et al.
    Int J Environ Res Public Health, 2021 01 14;18(2).
    PMID: 33466883 DOI: 10.3390/ijerph18020676
    The synthesis and secretion of cortisol are controlled by the hypothalamic-pituitary-adrenal axis. Cortisol exhibits a proper 24-h circadian rhythm that affects the brain, the autonomic nervous system, the heart, and the vasculature that prepares the cardiovascular system for optimal function during these anticipated behavioral cycles. A literature search was conducted using databases such as Google Scholar, PubMed, and Scopus. Relevant search terms included "circadian rhythm and cardiovascular", "cortisol", "cortisol and acute coronary syndrome", "cortisol and arrhythmias", "cortisol and sudden cardiac death", "cortisol and stroke", and "cardioprotective agents". A total of 120 articles were obtained on the basis of the above search. Lower levels of cortisol were seen at the beginning of sleep, while there was a rise towards the end of sleep, with the highest level reached at the moment the individual wakes up. In the present review, we discuss the role of 11β-hydroxysteroid dehydrogenase (11β-HSD1), which is a novel molecular target of interest for treating metabolic syndrome and type-2 diabetes mellitus. 11β-HSD1 is the major determinant of cortisol excess, and its inhibition alleviates metabolic abnormalities. The present review highlights the role of cortisol, which controls the circadian rhythm, and describes its effect on the cardiovascular system. The review provides a platform for future potential cardioprotective therapeutic agents.
  19. Exposure to Pb-halide perovskite nanoparticles can deliver bioavailable Pb but does not alter endogenous gut microbiota in zebrafish
    Patsiou D, Del Rio-Cubilledo C, Catarino AI, Summers S, Mohd Fahmi A, Boyle D, et al.
    Sci Total Environ, 2020 May 01;715:136941.
    PMID: 32041050 DOI: 10.1016/j.scitotenv.2020.136941
    Lead-halide perovskite nanoparticles (NPs) are a new technology, and investigation of toxicity is of considerable importance due to the potential lead (Pb) release into the environment. The aim of the study was to investigate aqueous and dietary toxicity of Pb-halide perovskite NP and Pb in zebrafish Danio rerio. Perovskite NP toxicity was evaluated in zebrafish by mortality, gene expression, histopathology, and phylogenetic analysis of gut microbiota. Zebrafish larvae were exposed to five Pb-halide perovskite NPs in parallel with Pb(NO3)2 exposures, and zebrafish adults were exposed to the three perovskite NPs that caused the strongest effect and Pb(NO3)2. No median lethal concentration (LC50) was observed for zebrafish larvae exposed to up to 200 mg/L of perovskite NPs for 96 h. Mortality, metallothionein 2 (mt2) and δ-aminolevulinic acid dehydratase (ala-d) gene expression (24-h exposure) in zebrafish larvae after aqueous perovskite NPs exposures did not differ from total Pb concentration - response curves. The lack of differences in mortality and gene expression between perovskite NPs and soluble Pb after aqueous exposure suggest that toxicity from perovskite NPs can be attributed to bioavailable Pb rather than nano-specific effects. Induction of mt2 and reduction of ala-d expression levels in liver tissues showed Pb bioavailability after 2-d and 4-d dietary exposure to perovskite-spiked feeds. Changes in gut microbiota of adult zebrafish were detected after 14-d exposure to Pb-spiked food, but no changes were detected from perovskite-NP spiked food. The phylogenetic analysis identified different microbiome profiles of Pb-fed fish compared to perovskite-fed fish suggesting a different mechanism of toxicity. Exposure to Pb-halide perovskite NPs led to absorption of Pb likely from release of Pb ions rather than absorption of NPs. Pb-halide perovskite NPs can release bioavailable Pb and this needs to be considered during the development of this technology.
  20. Fulltext Checklist of herpetofauna in the severely degraded ecosystem of Bidong Island, Peninsular Malaysia, South China Sea
    Fatihah-Syafiq M, Badli-Sham BH, Fahmi-Ahmad M, Aqmal-Naser M, Rizal SA, Azmi MSA, et al.
    Zookeys, 2020;985:143-162.
    PMID: 33223878 DOI: 10.3897/zookeys.985.54737
    A herpetofaunal inventory was conducted on Bidong Island, Terengganu, Peninsular Malaysia. It incorporates data from a recent herpetological survey conducted from 1 to 3 April 2019 with reptile records from previous publications. Specimens were collected with drift-fenced pitfall traps and taxa were recorded with visual encounter surveys (VES). In total, 18 species of reptiles and amphibians were recorded, including three species of frogs, 12 species of lizards, and three species of snakes. Six species from the present survey are new records for the island.
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