Browse publications by year: 2020

  1. Tan SW, Israf Ali DAB, Khaza'ai H, Wong JW, Vidyadaran S
    Cell Immunol, 2020 11;357:104200.
    PMID: 32979761 DOI: 10.1016/j.cellimm.2020.104200
    Tocopherols long dominated studies on vitamin E, although interest has shifted to tocotrienols. It was previously shown that δ-tocotrienol derived from palm oil reduced nitric oxide released by BV2 microglia as early as 18 h after lipopolysaccharide stimulation. The current study measured δ-tocotrienol uptake by BV2 over a 24 h incubation period and its anti-inflammatory effects on primary microglia. Uptake of 17.5 μg/mL δ-tocotrienol by BV2 microglia began as early as 5 min and rose steeply to 21 ± 3% of the amount administered at 24 h. The amount of δ-tocotrienol retained in the lipopolysaccharide-stimulated microglia at 24 h was 14 ± 2%, with no substantial difference seen in unstimulated microglia. The same δ-tocotrienol regimen reduced nitric oxide levels by 82% at 24 h after lipopolysaccharide stimulation (p 
    MeSH terms: Animals; Anti-Infective Agents/pharmacology; Antioxidants/pharmacology; Mice, Inbred C57BL; Nitric Oxide/metabolism; Tumor Necrosis Factor-alpha/metabolism; Vitamin E/analogs & derivatives*; Vitamin E/metabolism; Vitamin E/pharmacology; Microglia/drug effects*; Microglia/metabolism; Tocotrienols/metabolism; Tocotrienols/pharmacology; Mice; Nitric Oxide Synthase Type II/metabolism; Primary Cell Culture
  2. Mirza MU, Ahmad S, Abdullah I, Froeyen M
    Comput Biol Chem, 2020 Dec;89:107376.
    PMID: 32979815 DOI: 10.1016/j.compbiolchem.2020.107376
    Human ubiquitin carboxyl-terminal hydrolase-2 (USP2) inhibitors, such as thiopurine analogs, have been reported to inhibit SARS-CoV papain-like proteases (PLpro). The PLpro have significant functional implications in the innate immune response during SARS-CoV-2 infection and considered an important antiviral target. Both proteases share strikingly similar USP fold with right-handed thumb-palm-fingers structural scaffold and conserved catalytic triad Cys-His-Asp/Asn. In this urgency situation of COVID-19 outbreak, there is a lack of in-vitro facilities readily available to test SARS-CoV-2 inhibitors in whole-cell assays. Therefore, we adopted an alternate route to identify potential USP2 inhibitor through integrated in-silico efforts. After an extensive virtual screening protocol, the best compounds were selected and tested. The compound Z93 showed significant IC50 value against Jurkat (9.67 μM) and MOTL-4 cells (11.8 μM). The binding mode of Z93 was extensively analyzed through molecular docking, followed by MD simulations, and molecular interactions were compared with SARS-CoV-2. The relative binding poses of Z93 fitted well in the binding site of both proteases and showed consensus π-π stacking and H-bond interactions with histidine and aspartate/asparagine residues of the catalytic triad. These results led us to speculate that compound Z93 might be the first potential chemical lead against SARS-CoV-2 PLpro, which warrants in-vitro evaluations.
    MeSH terms: Antiviral Agents/pharmacology*; Antiviral Agents/chemistry; Drug Evaluation, Preclinical; Humans; Models, Molecular; Molecular Structure; Jurkat Cells; Ubiquitin Thiolesterase/antagonists & inhibitors*; Ubiquitin Thiolesterase/metabolism; Cell Line, Tumor
  3. Makkar SR, Lipnicki DM, Crawford JD, Kochan NA, Castro-Costa E, Lima-Costa MF, et al.
    J Gerontol A Biol Sci Med Sci, 2020 09 25;75(10):1863-1873.
    PMID: 32396611 DOI: 10.1093/gerona/glaa116
    We aimed to examine the relationship between Apolipoprotein E ε4 (APOE*4) carriage on cognitive decline, and whether these associations were moderated by sex, baseline age, ethnicity, and vascular risk factors. Participants were 19,225 individuals aged 54-103 years from 15 longitudinal cohort studies with a mean follow-up duration ranging between 1.2 and 10.7 years. Two-step individual participant data meta-analysis was used to pool results of study-wise analyses predicting memory and general cognitive decline from carriage of one or two APOE*4 alleles, and moderation of these associations by age, sex, vascular risk factors, and ethnicity. Separate pooled estimates were calculated in both men and women who were younger (ie, 62 years) and older (ie, 80 years) at baseline. Results showed that APOE*4 carriage was related to faster general cognitive decline in women, and faster memory decline in men. A stronger dose-dependent effect was observed in older men, with faster general cognitive and memory decline in those carrying two versus one APOE*4 allele. Vascular risk factors were related to an increased effect of APOE*4 on memory decline in younger women, but a weaker effect of APOE*4 on general cognitive decline in older men. The relationship between APOE*4 carriage and memory decline was larger in older-aged Asians than Whites. In sum, APOE*4 is related to cognitive decline in men and women, although these effects are enhanced by age and carriage of two APOE*4 alleles in men, a higher numbers of vascular risk factors during the early stages of late adulthood in women, and Asian ethnicity.
    MeSH terms: Age Factors; Aged; Aged, 80 and over; Aging/genetics*; Alleles; Female; Genotype; Humans; Longitudinal Studies; Male; Middle Aged; Risk Factors; Sex Factors; Apolipoprotein E4/genetics*; Mild Cognitive Impairment/ethnology; Mild Cognitive Impairment/genetics*
  4. Lam UN, Siddik NSFMM, Yussof SJM, Ilenghoven D, Ibrahim S
    Arch Plast Surg, 2020 Sep;47(5):490-492.
    PMID: 32971604 DOI: 10.5999/aps.2020.01347
  5. Zulkifli NI, Muhamad M, Mohamad Zain NN, Tan WN, Yahaya N, Bustami Y, et al.
    Molecules, 2020 Sep 22;25(18).
    PMID: 32971740 DOI: 10.3390/molecules25184332
    A bottom-up approach for synthesizing silver nanoparticles (AgNPs-GA) phytomediated by Garcinia atroviridis leaf extract is described. Under optimized conditions, the AgNPs-GA were synthesized at a concentration of 0.1 M silver salt and 10% (w/v) leaf extract, 1:4 mixing ratio of reactants, pH 3, temperature 32 °C and 72 h reaction time. The AgNPs-GA were characterized by various analytical techniques and their size was determined to be 5-30 nm. FTIR spectroscopy indicates the role of phenolic functional groups in the reduction of silver ions into AgNPs-GA and in supporting their subsequent stability. The UV-Visible spectrum showed an absorption peak at 450 nm which reflects the surface plasmon resonance (SPR) of AgNPs-GA and further supports the stability of these biosynthesized nanoparticles. SEM, TEM and XRD diffractogram analyses indicate that AgNPs-GA were spherical and face-centered-cubic in shape. This study also describes the efficacy of biosynthesized AgNPs-GA as anti-proliferative agent against human breast cancer cell lines, MCF-7 and MCF-7/TAMR-1. Our findings indicate that AgNPs-GA possess significant anti-proliferative effects against both the MCF-7 and MCF-7/TAMR-1 cell lines, with inhibitory concentration at 50% (IC50 values) of 2.0 and 34.0 µg/mL, respectively, after 72 h of treatment. An induction of apoptosis was evidenced by flow cytometry using Annexin V-FITC and propidium iodide staining. Therefore, AgNPs-GA exhibited its anti-proliferative activity via apoptosis on MCF-7 and MCF-7/TAMR-1 breast cancer cells in vitro. Taken together, the leaf extract from Garcinia atroviridis was found to be highly capable of producing AgNPs-GA with favourable physicochemical and biological properties.
    MeSH terms: Antineoplastic Agents/chemical synthesis*; Antineoplastic Agents/pharmacology*; Antineoplastic Agents/chemistry; Breast Neoplasms/pathology*; Cell Survival/drug effects; Humans; Plant Extracts/chemistry; Silver/pharmacology*; Silver/chemistry*; Apoptosis/drug effects*; Garcinia/chemistry; Cell Proliferation/drug effects; Metal Nanoparticles/chemistry*; Green Chemistry Technology; Chemistry Techniques, Synthetic; MCF-7 Cells
  6. Ahmed SW, Hussain G, Altaf K, Ali S, Alkahtani M, Abidi MH, et al.
    Polymers (Basel), 2020 Sep 22;12(9).
    PMID: 32971747 DOI: 10.3390/polym12092155
    The scope of additive manufacturing, particularly fused deposition modelling (FDM), can indeed be explored with the fabrication of multi-material composite laminates using this technology. Laminar composite structures made up of two distinct materials, namely acrylonitrile butadiene styrene (ABS) and carbon fiber reinforced polylactic acid (CF-PLA), were produced using the FDM process. The current study analyzes the effect of various printing parameters on the interfacial bond strength (IFBS) of the ABS/CF-PLA laminar composite by employing response surface methodology. The physical examination of the tested specimens revealed two failure modes, where failure mode 1 possessed high IFBS owing to the phenomenon of material patch transfer. Contrarily, failure mode 2 yielded low IFBS, while no patch transfer was observed. The analysis of variance (ANOVA) revealed that printing parameters were highly interactive in nature. After extensive experimentation, it was revealed that good quality of IFBS is attributed to the medium range of printing speed, high infill density, and low layer height. At the same time, a maximum IFBS of 20.5 MPa was achieved. The study presented an empirical relation between printing parameters and IFBS that can help in forecasting IFBS at any given printing parameters. Finally, the optimized printing conditions were also determined with the aim to maximize IFBS.
    MeSH terms: Acrylonitrile; Analysis of Variance; Butadienes; Physical Examination; Polyesters; Technology; Styrene; Printing, Three-Dimensional
  7. Costa F, Traoré-Dubuis A, Álvarez L, Lozano AI, Ren X, Dorn A, et al.
    Int J Mol Sci, 2020 Sep 22;21(18).
    PMID: 32971806 DOI: 10.3390/ijms21186947
    Electron scattering cross sections for pyridine in the energy range 0-100 eV, which we previously measured or calculated, have been critically compiled and complemented here with new measurements of electron energy loss spectra and double differential ionization cross sections. Experimental techniques employed in this study include a linear transmission apparatus and a reaction microscope system. To fulfill the transport model requirements, theoretical data have been recalculated within our independent atom model with screening corrected additivity rule and interference effects (IAM-SCAR) method for energies above 10 eV. In addition, results from the R-matrix and Schwinger multichannel with pseudopotential methods, for energies below 15 eV and 20 eV, respectively, are presented here. The reliability of this complete data set has been evaluated by comparing the simulated energy distribution of electrons transmitted through pyridine, with that observed in an electron-gas transmission experiment under magnetic confinement conditions. In addition, our representation of the angular distribution of the inelastically scattered electrons is discussed on the basis of the present double differential cross section experimental results.
    MeSH terms: Electron Transport; Electrons*; Models, Chemical*; Pyridines/chemistry*
  8. Wong KJ, Johar M, Koloor SSR, Petrů M, Tamin MN
    Polymers (Basel), 2020 Sep 22;12(9).
    PMID: 32971855 DOI: 10.3390/polym12092162
    It is necessary to consider the influence of moisture damage on the interlaminar fracture toughness for composite structures that are used for outdoor applications. However, the studies on the progressive variation of the fracture toughness as a function of moisture content M (%) is rather limited. In this regard, this study focuses on the characterization of mode II delamination of carbon/epoxy composites conditioned at 70 °C/85% relative humidity (RH). End-notched flexure test is conducted for specimens aged at various moisture absorption levels. Experimental results reveal that mode II fracture toughness degrades with the moisture content, with a maximum of 23% decrement. A residual property model is used to predict the variation of the fracture toughness with the moisture content. Through numerical simulations, it is found that the approaches used to estimate the lamina and cohesive properties are suitable to obtain reliable simulation results. In addition, the damage initiation is noticed during the early loading stage; however, the complete damage is only observed when the numerical peak load is achieved. Results from the present research could serve as guidelines to predict the residual properties and simulate the mode II delamination behavior under moisture attack.
    MeSH terms: Biochemical Phenomena; Carbon; Composite Resins; Epoxy Resins; Humidity; Physical Phenomena
  9. N Amirrah I, Mohd Razip Wee MF, Tabata Y, Bt Hj Idrus R, Nordin A, Fauzi MB
    Polymers (Basel), 2020 Sep 22;12(9).
    PMID: 32972012 DOI: 10.3390/polym12092168
    Diabetic foot ulcer (DFU) is a chronic wound frequently delayed from severe infection. Wound dressing provides an essential barrier between the ulcer and the external environment. This review aimed to analyse the effectiveness of antibacterial collagen-based dressing for DFU treatment in a clinical setting. An electronic search in four databases, namely, Scopus, PubMed, Ovid MEDLINE(R), and ISI Web of Science, was performed to obtain relevant articles published within the last ten years. The published studies were included if they reported evidence of (1) collagen-based antibacterial dressing or (2) wound healing for diabetic ulcers, and (3) were written in English. Both randomised and non-randomised clinical trials were included. The search for relevant clinical studies (n) identified eight related references discussing the effectiveness of collagen-based antibacterial wound dressings for DFU comprising collagen impregnated with polyhexamethylene biguanide (n = 2), gentamicin (n = 3), combined-cellulose and silver (n = 1), gentian violet/methylene blue mixed (n = 1), and silver (n = 1). The clinical data were limited by small sample sizes and multiple aetiologies of chronic wounds. The evidence was not robust enough for a conclusive statement, although most of the studies reported positive outcomes for the use of collagen dressings loaded with antibacterial properties for DFU wound healing. This study emphasises the importance of having standardised clinical trials, larger sample sizes, and accurate reporting for reliable statistical evidence confirming DFU treatment efficiency.
    MeSH terms: Anti-Bacterial Agents; Bandages; Biguanides; Cellulose; Collagen; Gentamicins; Gentian Violet; Methylene Blue; Silver; Wound Healing; MEDLINE; Diabetic Foot; Sample Size; PubMed
  10. Selvanathan V, Ruslan MH, Aminuzzaman M, Muhammad G, Amin N, Sopian K, et al.
    Polymers (Basel), 2020 Sep 22;12(9).
    PMID: 32972016 DOI: 10.3390/polym12092170
    A starch-resorcinol-formaldehyde (RF)-lithium triflate (LiTf) based biodegradable polymer electrolyte membrane was synthesized via the solution casting technique. The formation of RF crosslinks in the starch matrix was found to repress the starch's crystallinity as indicated by the XRD data. Incorporation of the RF plasticizer improved the conductivity greatly, with the highest room-temperature conductivity recorded being 4.29 × 10-4 S cm-1 achieved by the starch:LiTf:RF (20 wt.%:20 wt.%:60 wt.%) composition. The enhancement in ionic conductivity was an implication of the increase in the polymeric amorphous region concurrent with the suppression of the starch's crystallinity. Chemical complexation between the plasticizer, starch, and lithium salt components in the electrolyte was confirmed by FTIR spectra.
  11. Low ZY, Farouk IA, Lal SK
    Viruses, 2020 09 22;12(9).
    PMID: 32972027 DOI: 10.3390/v12091058
    Traditionally, drug discovery utilises a de novo design approach, which requires high cost and many years of drug development before it reaches the market. Novel drug development does not always account for orphan diseases, which have low demand and hence low-profit margins for drug developers. Recently, drug repositioning has gained recognition as an alternative approach that explores new avenues for pre-existing commercially approved or rejected drugs to treat diseases aside from the intended ones. Drug repositioning results in lower overall developmental expenses and risk assessments, as the efficacy and safety of the original drug have already been well accessed and approved by regulatory authorities. The greatest advantage of drug repositioning is that it breathes new life into the novel, rare, orphan, and resistant diseases, such as Cushing's syndrome, HIV infection, and pandemic outbreaks such as COVID-19. Repositioning existing drugs such as Hydroxychloroquine, Remdesivir, Ivermectin and Baricitinib shows good potential for COVID-19 treatment. This can crucially aid in resolving outbreaks in urgent times of need. This review discusses the past success in drug repositioning, the current technological advancement in the field, drug repositioning for personalised medicine and the ongoing research on newly emerging drugs under consideration for the COVID-19 treatment.
    MeSH terms: Humans; Pneumonia, Viral/drug therapy*; Pneumonia, Viral/epidemiology; Coronavirus Infections/drug therapy*; Coronavirus Infections/epidemiology; Rare Diseases/drug therapy; Precision Medicine; Pandemics; Pharmaceutical Research
  12. Che Alhadi S, Wan Zain WZ, Zahari Z, Md Hashim MN, Syed Abd Aziz SH, Zakaria Z, et al.
    Ann Coloproctol, 2020 Dec;36(6):409-414.
    PMID: 32972105 DOI: 10.3393/ac.2020.08.27
    PURPOSE: Guaiac fecal occult blood test (gFOBT) has been the standard for colorectal screening but it has low sensitivity and specificity. This study evaluated the use of fecal tumor M2-pyruvate kinase (M2-PK) for detection of colorectal cancer and to compare with the current surveillance tool; gFOBT in symptomatic adult subjects underwent colonoscopy.

    METHODS: Stool samples were collected prospectively from symptomatic adults who had elective colonoscopy from September 2014 to January 2016 and were analyzed with the ScheBo M2-PK Quick test and laboratory detection of fecal hemoglobin.

    RESULTS: The results were correlated to the colonoscopy findings and/or histopathology report. Eighty-five subjects (age of 56.8 ± 15.3 years [mean ± standard deviation]) were recruited with a total of 17 colorectal cancer (20.0%) and 10 colorectal adenoma patients (11.8%). The sensitivity of M2-PK test in colorectal cancer detection was higher than gFOBT (100% vs. 64.7%). M2-PK test had a lower specificity when compared to gFOBT (72.5% vs. 88.2%) in colorectal cancer detection. The positive and negative predictive values were 47.2% and 100% for M2-PK test and 57.9% and 90.9% for gFOBT.

    CONCLUSION: Fecal M2-PK Quick test has a high sensitivity for detection of colorectal cancer when compared to gFOBT, making it the potential choice for colorectal tumor screening biomarker in the future.

    MeSH terms: Adenoma; Adult; Colonoscopy; Guaiac; Hemoglobins; Humans; Laboratories; Mass Screening; Occult Blood; Predictive Value of Tests; Pyruvate Kinase; Reference Standards; Colorectal Neoplasms; Biomarkers; Early Detection of Cancer
  13. Nankali A, Kazeminia M, Jamshidi PK, Shohaimi S, Salari N, Mohammadi M, et al.
    Health Qual Life Outcomes, 2020 Sep 24;18(1):314.
    PMID: 32972380 DOI: 10.1186/s12955-020-01561-3
    BACKGROUND: Endometriosis is one of the most common causes of infertility. The causes of the disease and its definitive treatments are still unclear. Moreover, Anti-Mullerian Hormone (AMH) is a glycoprotein dimer that is a member of the transient growth factors family. This research work aimed to identify the effect of unilateral and bilateral laparoscopic surgery for endometriosis on AMH levels after 3 months, and 6 months, using meta-analysis.

    METHODS: In this study, the articles published in national and international databases of SID, MagIran, IranMedex, IranDoc, Cochrane, Embase, Science Direct, Scopus, PubMed, and Web of Science (ISI) were searched to find electronically published studies between 2010 and 2019. The heterogeneous index between studies was determined using the I2 index.

    RESULTS: In this meta-analysis and systematic review, 19 articles were eligible for inclusion in the study. The standardized mean difference was obtained in examining of unilateral laparoscopic surgery for endometriosis (before intervention 2.8 ± 0.11, and after 3 months 2.05 ± 0.13; and before intervention 3.1 ± 0.46 and after 6 months 2.08 ± 0.31), and in examining bilateral laparoscopic surgery for endometriosis examination (before intervention 2.0 ± 08.08, and after 3 months 1.1 ± 0.1; and before intervention 2.9 ± 0.23 and after 6 months 1.4 ± 0.19).

    CONCLUSION: The results of this study demonstrate that unilateral and bilateral laparoscopic surgery for endometriosis is effective on AMH levels, and the level decreases in both comparisons.

    MeSH terms: Adult; Endometriosis/surgery*; Female; Humans; Laparoscopy/methods*; Quality of Life; Anti-Mullerian Hormone/blood*; Ovarian Reserve
  14. Wong MNL, Tang IP, Chor YK, Lau KS, John AR, Hii KC, et al.
    BMC Pediatr, 2020 09 24;20(1):448.
    PMID: 32972390 DOI: 10.1186/s12887-020-02348-7
    BACKGROUND: Haemoptysis is an uncommon presenting symptom in children and is usually caused by acute lower respiratory tract infection or foreign body aspiration. We report a rare case of right unilateral pulmonary vein atresia (PVA) as the underlying aetiology of recurrent haemoptysis in a child.

    CASE PRESENTATION: A 4 years old girl presented with history of recurrent haemoptysis. Bronchoscopic evaluation excluded a foreign body aspiration but revealed right bronchial mucosal hyperaemia and varices. Diagnosis of right unilateral PVA was suspected on transthoracic echocardiography which demonstrated hypoplastic right pulmonary artery and non-visualization of right pulmonary veins. Final diagnosis was confirmed on cardiac CT angiography. A conservative treatment approach was opted with consideration for pneumonectomy in future when she is older.

    CONCLUSION: Rarer causes should be considered when investigating for recurrent haemoptysis in children. Bronchoscopy and cardiac imaging are useful tools to establish the diagnosis of unilateral PVA in our case.

    MeSH terms: Child; Child, Preschool; Female; Hemoptysis/etiology; Humans; Lung; Lung Diseases*; Vascular Malformations*
  15. Parvin W, Govender N, Othman R, Jaafar H, Rahman M, Wong MY
    Sci Rep, 2020 Sep 24;10(1):15621.
    PMID: 32973199 DOI: 10.1038/s41598-020-72156-7
    Pseudomonas aeruginosa developed its biocontrol agent property through the production of antifungal derivatives, with the phenazine among them. In this study, the applications of crude phenazine synthesized by Pseudomonas aeruginosa UPMP3 and hexaconazole were comparatively evaluated for their effectiveness to suppress basal stem rot infection in artificially G. boninense-challenged oil palm seedlings. A glasshouse experiment under the randomized completely block design was set with the following treatments: non-inoculated seedlings, G. boninense inoculated seedlings, G. boninense inoculated seedlings with 1 mg/ml phenazine application, G. boninense inoculated seedlings with 2 mg/ml phenazine application and G. boninense inoculated seedlings with 0.048 mg/ml hexaconazole application. Seedlings were screened for disease parameters and plant vigour traits (plant height, plant fresh weight, root fresh, and dry weight, stem diameter, and total chlorophyll) at 1-to-4 month post-inoculation (mpi). The application of 2 mg/ml phenazine significantly reduced disease severity (DS) at 44% in comparison to fungicide application (DS = 67%). Plant vigour improved from 1 to 4 mpi and the rate of disease reduction in seedlings with phenazine application (2 mg/ml) was twofold greater than hexaconazole. At 4, 6 and 8 wpi, an up-regulation of chitinase and β-1,3 glucanase genes in seedlings treated with phenazine suggests the involvement of induced resistance in G. boninense-oil palm pathosystem.
    MeSH terms: Phenazines/pharmacology*; Plant Diseases/immunology*; Plant Diseases/microbiology; Pseudomonas aeruginosa/chemistry*; Plant Roots/drug effects; Plant Roots/growth & development*; Plant Roots/microbiology; Arecaceae/drug effects; Arecaceae/growth & development*; Arecaceae/microbiology; Ganoderma/pathogenicity*; Seedlings/drug effects; Seedlings/growth & development*; Seedlings/microbiology
  16. Md Noh MSF
    J Cent Nerv Syst Dis, 2020;12:1179573520955008.
    PMID: 32973377 DOI: 10.1177/1179573520955008
    Myelin oligodendrocyte glycoprotein-antibodies (MOG-IgG) are associated with acquired inflammatory demyelinating syndromes, seen predominantly in children and young adults. The overlapping clinical and radiological features of the heterogenous spectrum of demyelinating central nervous system (CNS) diseases makes the detection of MOG-IgG antibodies important for prognosis and treatment decisions. Herein, we describe the occurrence of MOG-IgG associated disease presenting as acute disseminated encephalomyelitis (ADEM), with spinal MRI findings of centrally located long cord lesion in a 14-month old child.
  17. Lee NLY, Huang D, Quek ZBR, Lee JN, Wainwright BJ
    IMA Fungus, 2020;11:17.
    PMID: 32974121 DOI: 10.1186/s43008-020-00042-y
    Mangrove forests are key tropical marine ecosystems that are rich in fungi, but our understanding of fungal communities associated with mangrove trees and their various organs remains limited because much of the diversity lies within the microbiome. In this study, we investigated the fungal communities associated with the mangrove tree Sonneratia alba throughout Peninsular Malaysia and Singapore. At each sampling location, we collected leaves, fruits, pneumatophores and sediment samples and performed amplicon sequencing of the ribosomal internal transcribed spacer 1 to characterise the associated communities. Results show distinct fungal communities at each sampled location with further differentiation according to the plant part. We find a significant distance decay of similarity, particularly for sediment samples due to the greater variability of sediment environments relative to the more stable fungal habitats provided by living plant organs. We are able to assign taxonomy to the majority of sequences from leaves and fruits, but a much larger portion of the sequences recovered from pneumatophores and sediment samples could not be identified. This pattern underscores the limited mycological research performed in marine environments and demonstrates the need for a concerted research effort on multiple species to fully characterise the coastal microbiome and its role in the functioning of marine ecosystems.
  18. Kikuchi F, Aoki K, Ohdachi SD, Tsuchiya K, Motokawa M, Jogahara T, et al.
    PMID: 32974220 DOI: 10.3389/fcimb.2020.00438
    Murid and cricetid rodents were previously believed to be the principal reservoir hosts of hantaviruses. Recently, however, multiple newfound hantaviruses have been discovered in shrews, moles, and bats, suggesting a complex evolutionary history. Little is known about the genetic diversity and geographic distribution of the prototype shrew-borne hantavirus, Thottapalayam thottimvirus (TPMV), carried by the Asian house shrew (Suncus murinus), which is widespread in Asia, Africa, and the Middle East. Comparison of TPMV genomic sequences from two Asian house shrews captured in Myanmar and Pakistan with TPMV strains in GenBank revealed that the Myanmar TPMV strain (H2763) was closely related to the prototype TPMV strain (VRC66412) from India. In the L-segment tree, on the other hand, the Pakistan TPMV strain (PK3629) appeared to be the most divergent, followed by TPMV strains from Nepal, then the Indian-Myanmar strains, and finally TPMV strains from China. The Myanmar strain of TPMV showed sequence similarity of 79.3-96.1% at the nucleotide level, but the deduced amino acid sequences showed a high degree of conservation of more than 94% with TPMV strains from Nepal, India, Pakistan, and China. Cophylogenetic analysis of host cytochrome b and TPMV strains suggested that the Pakistan TPMV strain was mismatched. Phylogenetic trees, based on host cytochrome b and cytochrome c oxidase subunit I genes of mitochondrial DNA, and on host recombination activating gene 1 of nuclear DNA, suggested that the Asian house shrew and Asian highland shrew (Suncus montanus) comprised a species complex. Overall, the geographic-specific clustering of TPMV strains in Asian countries suggested local host-specific adaptation. Additional in-depth studies are warranted to ascertain if TPMV originated in Asian house shrews on the Indian subcontinent.
    MeSH terms: Africa; Animals; China; India; Nepal; Pakistan; Phylogeny; Shrews*; Genetic Variation*; Phylogeography
  19. Wan Mat Khalir WKA, Shameli K, Jazayeri SD, Othman NA, Che Jusoh NW, Hassan NM
    Front Chem, 2020;8:620.
    PMID: 32974269 DOI: 10.3389/fchem.2020.00620
    Silver nanoparticles (Ag-NPs) have been established as antibacterial nanoparticles and have been innovatively developed to overcome the occurrence of antibiotic resistance in the environment. In this study, an environmentally friendly and easy method of the biosynthesis of Ag-NPs plants, mediated by aqueous extract stem extract of Entada spiralis (E. spiralis), was successfully developed. The E. spiralis/Ag-NPs samples were characterized using spectroscopy and the microscopic technique of UV-visible (UV-vis), X-ray Diffraction (XRD), Field Emission Transmission Electron Microscope (FETEM), zeta potential, and Fourier Transform Infrared (FTIR) analyses. Surface Plasmon Resonance (SPR) absorption at 400-450 nm in the UV-vis spectra established the formation of E. spiralis/Ag-NPs. The crystalline structure of E. spiralis/Ag-NPs was displayed in the XRD analysis. The small size, around 18.49 ± 4.23 nm, and spherical shape of Ag-NPs with good distribution was observed in the FETEM image. The best physicochemical parameters on Ag-NPs biosynthesis using E. spiralis extract occurred at a moderate temperature (~52.0°C), 0.100 M of silver nitrate, 2.50 g of E. spiralis dosage and 600 min of stirring reaction time. The antibacterial activity was tested against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Proteus vulgaris using an antibacterial disk diffusion assay. Based on the results, it is evident that E. spiralis/Ag-NPs are susceptible to all the bacteria and has promising potential to be applied in both the industry and medical fields.
    MeSH terms: Anti-Bacterial Agents; Drug Resistance, Microbial; Escherichia coli; Fourier Analysis; Proteus vulgaris; Reaction Time; Silver; Silver Nitrate; Staphylococcus aureus; Enterococcus faecalis; Temperature; X-Ray Diffraction; Spectroscopy, Fourier Transform Infrared; Surface Plasmon Resonance; Metal Nanoparticles
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