Displaying publications 161 - 180 of 608 in total

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  1. Fulltext Design, synthesis and biological profile of heterocyclic benzimidazole analogues as prospective antimicrobial and antiproliferative agents
    Tahlan S, Kumar S, Ramasamy K, Lim SM, Shah SAA, Mani V, et al.
    BMC Chem, 2019 Dec;13(1):50.
    PMID: 31384798 DOI: 10.1186/s13065-019-0567-x
    Background: Nitrogen containing heterocycles are widely used and investigated by pharmaceutical industry, as they are important in discovery and designing of new drug molecules. Drugs with a benzimidazole nucleus possess exclusive structural features and electron-rich atmosphere, which enable them to bind to a number of biologically important targets and result in a wide range of activities. This has served as the basis of the present study whereby new scaffolds with benzimidazole moiety were designed and synthesized.

    Methods: The structures of synthesized compounds were confirmed by physicochemical and spectral means. The synthesized compounds were screened for their antimicrobial and antiproliferative activities by tube dilution and Sulforhodamine B (SRB) assays, respectively.

    Results and conclusion: The in vitro biological screening results revealed that compound Z24 exhibited promising antimicrobial and anticancer activities which are comparable to standards.

  2. Fulltext Synthesis, molecular modelling and biological significance of N-(4-(4-bromophenyl) thiazol-2-yl)-2-chloroacetamide derivatives as prospective antimicrobial and antiproliferative agents
    Sharma D, Kumar S, Narasimhan B, Ramasamy K, Lim SM, Shah SAA, et al.
    BMC Chem, 2019 Dec;13(1):46.
    PMID: 31384794 DOI: 10.1186/s13065-019-0564-0
    To combat the antimicrobial and anticancer drug resistance by pathogens and cancerous cells, efforts has been made to study the pharmacological activities of newly synthesized N-(4-(4-bromophenyl)thiazol-2-yl)-2-chloroacetamide derivatives. The molecular structures of the synthesized derivatives were confirmed by their physicochemical properties and spectroanalytical data (NMR, IR and elemental). The synthesized compounds were evaluated for their in vitro antimicrobial activity against bacterial (Gram positive and Gram negative) and fungal species using turbidimetric method and anticancer activity against oestrogen receptor positive human breast adenocarcinoma cancer cell line (MCF7) by Sulforhodamine B (SRB) assay. Molecular docking studies were carried out to study the binding mode of active compounds with receptor using Schrodinger v11.5. The antimicrobial activity results revealed that compounds d1, d2 and d3 have promising antimicrobial activity. Anticancer screening results indicated that compounds d6 and d7 were found to be the most active ones against breast cancer cell line. Furthermore, the molecular docking study demonstrated that compounds d1, d2, d3, d6 and d7 displayed good docking score within binding pocket of the selected PDB ID (1JIJ, 4WMZ and 3ERT) and has the potential to be used as lead compounds for rational drug designing.
  3. Fulltext Computational approaches: discovery of GTPase HRas as prospective drug target for 1,3-diazine scaffolds
    Kumar S, Sharma D, Narasimhan B, Ramasamy K, Shah SAA, Lim SM, et al.
    BMC Chem, 2019 Dec;13(1):96.
    PMID: 31355369 DOI: 10.1186/s13065-019-0613-8
    Heterocyclic 1,3-diazine nucleus is a valuable pharmacophore in the field of medicinal chemistry and exhibit a wide spectrum of biological activities. PharmMapper, a robust online tool used for establishing the target proteins based on reverse pharmacophore mapping. PharmMapper study is carried out to explore the pharmacological activity of 1,3-diazine derivatives using reverse docking program. PharmMapper, an open web server was used to recognize for all the feasible target proteins for the developed compounds through reverse pharmacophore mapping. The results were analyzed via molecular docking with maestro v11.5 (Schrodinger 2018-1) using GTPase HRas as possible target. The molecular docking studies displayed the binding behavior of 1,3-diazine within GTP binding pocket. From the docking study compounds s3 and s14 showed better docked score with anticancer potency against cancer cell line (HCT116). Hence, the GTPase HRas may be the possible target of 1,3-diazine derivatives for their anticancer activity where the retrieved information may be quite useful for developing rational drug designing. Furthermore the selected 1,3-diazine compounds were evaluated for their in vitro anticancer activity against murine macrophages cell line. 1,3-Diazine compounds exhibited good selectivity of the compounds towards the human colorectal carcinoma cell line instead of the murine macrophages. The toxicity study of the most active compounds was also performed on non cancerous HEK-293 cell line.
  4. Fulltext Molecular docking, synthesis and biological significance of pyrimidine analogues as prospective antimicrobial and antiproliferative agents
    Kumar S, Kaushik A, Narasimhan B, Shah SAA, Lim SM, Ramasamy K, et al.
    BMC Chem, 2019 Dec;13(1):85.
    PMID: 31384832 DOI: 10.1186/s13065-019-0601-z
    Pyrimidine nucleus is a significant pharmacophore that exhibited excellent pharmacological activities. A series of pyrimidine scaffolds was synthesized and its chemical structures were confirmed by physicochemical and spectral analysis. The synthesized compounds were evaluated for their antimicrobial potential towards Gram positive and negative bacteria as well as fungal species. They were also assessed for their anticancer activity toward a human colorectal carcinoma cell line (HCT116). Whilst results of antimicrobial potential revealed that compounds Ax2, Ax3, Ax8 and Ax14 exhibited better activity against tested microorganisms, the results of antiproliferative activity indicated that compounds Ax7 and Ax10 showed excellent activity against HCT116. Further, the molecular docking of pyrimidine derivatives Ax1, Ax9 and Ax10 with CDK8 (PDB id: 5FGK) protein indicated that moderate to better docking results within the binding pocket. Compounds Ax8 and Ax10 having significant antimicrobial and anticancer activities may be selected as lead compounds for the development of novel antimicrobial and anticancer agent, respectively.
  5. One-pot microwave assisted stereoselective synthesis of novel dihydro-2'H-spiro[indene-2,1'-pyrrolo-[3,4-c]pyrrole]-tetraones and evaluation of their antimycobacterial activity and inhibition of AChE
    Bharkavi C, Vivek Kumar S, Ashraf Ali M, Osman H, Muthusubramanian S, Perumal S
    Bioorg Med Chem Lett, 2017 Jul 15;27(14):3071-3075.
    PMID: 28552337 DOI: 10.1016/j.bmcl.2017.05.050
    An efficient one-pot microwave assisted stereoselective synthesis of novel dihydro-2'H-spiro[indene-2,1'-pyrrolo[3,4-c]pyrrole]-tetraone derivatives through three-component 1,3-dipolar cycloaddition of azomethine ylides generated in situ from ninhydrin and sarcosine with a series of 1-aryl-1H-pyrrole-2,5-diones is described. The synthesised compounds were screened for their antimycobacterial and AChE inhibition activities. Compound 4b (IC50 1.30µM) has been found to display twelve fold antimycobacterial activity compared to cycloserine and it is thirty seven times more active than pyrimethamine. Compound 4h displays maximum AchE inhibitory activity with IC50 value of 0.78±0.01µmol/L.
  6. Evaluating heavy metals contamination in soil and vegetables in the region of North India: Levels, transfer and potential human health risk analysis
    Gupta N, Yadav KK, Kumar V, Krishnan S, Kumar S, Nejad ZD, et al.
    Environ Toxicol Pharmacol, 2021 Feb;82:103563.
    PMID: 33310081 DOI: 10.1016/j.etap.2020.103563
    This study determined the heavy metals (HMs) accumulation in different vegetables in different seasons and attributed a serious health hazard to human adults due to the consumption of such vegetables in Jhansi. The total amounts of zinc (Zn), lead (Pb), nickel (Ni), manganese (Mn), copper (Cu), cobalt (Co), and cadmium (Cd) were analysed in 28 composite samples of soil and vegetables (Fenugreek, spinach, eggplant, and chilli) collected from seven agricultural fields. The transfer factor (TF) of HMs from soil to analysed vegetables was calculated, and significant non-carcinogenic health risks due to exposure to analysed heavy metals via consumption of these vegetables were computed. The statistical analysis involving Principal Component Analysis (PCA) and Pearson's correlation matrix suggested that anthropogenic activities were a major source of HMs in the study areas. The target hazard quotient of Cd, Mn, and Pb for fenugreek (2.156, 2.143, and 2.228, respectively) and spinach (3.697, 3.509, 5.539, respectively) exceeded the unity, indicating the high possibilities of non-carcinogenic health risks if regularly consumed by human beings. This study strongly suggests the continuous monitoring of soil, irrigation water, and vegetables to prohibit excessive accumulation in the food chain.
  7. Thermoresponsive surfaces designed for the proliferation and differentiation of human pluripotent stem cells
    Higuchi A, Hirad AH, Kumar SS, Munusamy MA, Alarfaj AA
    Acta Biomater, 2020 10 15;116:162-173.
    PMID: 32911107 DOI: 10.1016/j.actbio.2020.09.010
    Thermoresponsive surfaces enable the detachment of cells or cell sheets by decreasing the temperature of the surface when harvesting the cells. However, human pluripotent stem cells (hPSCs), such as embryonic stem cells and induced pluripotent stem cells, cannot be directly cultured on a thermoresponsive surface; hPSCs need a specific extracellular matrix to bind to the integrin receptors on their surfaces. We prepared a thermoresponsive surface by using poly(N-isopropylacrylamide-co-butylacrylate) and recombinant vitronectin to provide an optimal coating concentration for the hPSC culture. hPSCs can be cultured on the same thermoresponsive surface for 5 passages by partial detachment of the cells from the surface by decreasing the temperature for 30 min; then, the remaining hPSCs were subsequently cultured on the same dishes following the addition of new cultivation media. The detached cells, even after continual culture for five passages, showed high pluripotency, the ability to differentiate into cells derived from the 3 germ layers and the ability to undergo cardiac differentiation.
  8. Efficient differentiation of human pluripotent stem cells into cardiomyocytes on cell sorting thermoresponsive surface
    Sung TC, Su HC, Ling QD, Kumar SS, Chang Y, Hsu ST, et al.
    Biomaterials, 2020 09;253:120060.
    PMID: 32450407 DOI: 10.1016/j.biomaterials.2020.120060
    The current differentiation process of human pluripotent stem cells (hPSCs) into cardiomyocytes to enhance the purity of hPSC-derived cardiomyocytes requires some purification processes, which are laborious processes. We developed cell sorting plates, which are prepared from coating thermoresponsive poly(N-isopropylacrylamide) and extracellular matrix proteins. After hPSCs were induced into cardiomyocytes on the thermoresponsive surface coated with laminin-521 for 15 days, the temperature of the cell culture plates was decreased to 8-9 °C to detach the cells partially from the thermoresponsive surface. The detached cells exhibited a higher cardiomyocyte marker of cTnT than the remaining cells on the thermoresponsive surface as well as the cardiomyocytes after purification using conventional cell selection. The detached cells expressed several cardiomyocyte markers, such as α-actinin, MLC2a and NKX2.5. This study suggested that the purification of hPSC-derived cardiomyocytes using cell sorting plates with the thermoresponsive surface is a promising method for the purification of hPSC-derived cardiomyocytes without conventional laborious processes.
  9. Fulltext Very-low-dose aspirin and surveillance colonoscopy is cost-effective in secondary prevention of colorectal cancer in individuals with advanced adenomas: network meta-analysis and cost-effectiveness analysis
    Veettil SK, Kew ST, Lim KG, Phisalprapa P, Kumar S, Lee YY, et al.
    BMC Gastroenterol, 2021 Mar 20;21(1):130.
    PMID: 33743605 DOI: 10.1186/s12876-021-01715-7
    BACKGROUND: Individuals with advanced colorectal adenomas (ACAs) are at high risk for colorectal cancer (CRC), and it is unclear which chemopreventive agent (CPA) is safe and cost-effective for secondary prevention. We aimed to determine, firstly, the most suitable CPA using network meta-analysis (NMA) and secondly, cost-effectiveness of CPA with or without surveillance colonoscopy (SC).

    METHODS: Systematic review and NMA of randomised controlled trials were performed, and the most suitable CPA was chosen based on efficacy and the most favourable risk-benefit profile. The economic benefits of CPA alone, 3 yearly SC alone, and a combination of CPA and SC were determined using the cost-effectiveness analysis (CEA) in the Malaysian health-care perspective. Outcomes were reported as incremental cost-effectiveness ratios (ICERs) in 2018 US Dollars ($) per quality-adjusted life-year (QALY), and life-years (LYs) gained.

    RESULTS: According to NMA, the risk-benefit profile favours the use of aspirin at very-low-dose (ASAVLD, ≤ 100 mg/day) for secondary prevention in individuals with previous ACAs. Celecoxib is the most effective CPA but the cardiovascular adverse events are of concern. According to CEA, the combination strategy (ASAVLD with 3-yearly SC) was cost-saving and dominates its competitors as the best buy option. The probability of being cost-effective for ASAVLD alone, 3-yearly SC alone, and combination strategy were 22%, 26%, and 53%, respectively. Extending the SC interval to five years in combination strategy was more cost-effective when compared to 3-yearly SC alone (ICER of $484/LY gain and $1875/QALY). However, extending to ten years in combination strategy was not cost-effective.

    CONCLUSION: ASAVLD combined with 3-yearly SC in individuals with ACAs may be a cost-effective strategy for CRC prevention. An extension of SC intervals to five years can be considered in resource-limited countries.

  10. Fulltext Non-communicable Disease Surveillance in Malaysia: An Overview of Existing Systems and Priorities Going Forward
    Chandran A, Selva Kumar S, Hairi NN, Low WY, Mustapha FI
    Front Public Health, 2021;9:698741.
    PMID: 34295873 DOI: 10.3389/fpubh.2021.698741
    In 2012, the World Health Organization (WHO) set a comprehensive set of nine global voluntary targets, including the landmark "25 by 25" mortality reduction target, and 25 indicators. WHO has also highlighted the importance of Non-Communicable Disease (NCD) surveillance as a key action by Member States in addressing NCDs. This study aimed to examine the current national NCD surveillance tools, activities and performance in Malaysia based on the WHO Global Monitoring Framework for NCDs and to highlight gaps and priorities moving forward. A desk review was conducted from August to October in 2020, to examine the current national NCD surveillance activities in Malaysia from multiple sources. Policy and program documents relating to NCD surveillance in Malaysia from 2010 to 2020 were identified and analyzed. The findings of this review are presented according to the three major themes of the Global Monitoring Framework: monitoring of exposure/risk factor, monitoring of outcomes and health system capacity/response. Currently, there is a robust monitoring system for NCD Surveillance in Malaysia for indicators that are monitored by the WHO NCD Global Monitoring Framework, particularly for outcome and exposure monitoring. However, Malaysia still lacks data for the surveillance of the health system indicators of the framework. Although Malaysia has an NCD surveillance in place that is adequate for the WHO NCD Global Monitoring Framework, there are areas that require strengthening. The country must also look beyond these set of indicators in view of the increasing burden and impact of the COVID-19 pandemic. This includes incorporating mental health indicators and leveraging on alternate sources of data relating to behaviors.
  11. Fulltext Readiness towards online learning among physiotherapy undergraduates
    Ranganathan H, Singh DKA, Kumar S, Sharma S, Chua SK, Ahmad NB, et al.
    BMC Med Educ, 2021 Jul 10;21(1):376.
    PMID: 34246264 DOI: 10.1186/s12909-021-02803-8
    BACKGROUND: Online learning is an attractive option for educators, especially as means of overcoming the challenges posed by the global pandemic. Although it is best to evaluate student readiness prior to commencement of an online course, to ensure successful development and delivery of student-centric teaching and learning strategies, readiness towards online learning among physiotherapy undergraduates is unknown. The main aim of this study was to examine physiotherapy undergraduates' readiness towards online learning.

    METHODS: In this cross-sectional study, participants were selected through a combination of total population and convenience sampling. The Student Online Learning Readiness questionnaire was distributed among physiotherapy undergraduates from two public and two private universities in Malaysia to investigate their technical, social and communication competencies. Information about device characteristics were obtained to evaluate their equipment readiness. Descriptive and group comparisons were conducted using independent t-test, and analysis of variance with p  80% possessed smartphones and laptop) level of equipment readiness. Institution and gender had no significant effect on the level of readiness (p > 0.05). Year 1 and 2 had significantly higher levels of social competencies with instructor compared to final year physiotherapy undergraduates (p 

  12. Fulltext Grouping and Sponsoring Centric Green Coverage Model for Internet of Things
    Kumar V, Kumar S, AlShboul R, Aggarwal G, Kaiwartya O, Khasawneh AM, et al.
    Sensors (Basel), 2021 Jun 08;21(12).
    PMID: 34201100 DOI: 10.3390/s21123948
    Recently, green computing has received significant attention for Internet of Things (IoT) environments due to the growing computing demands under tiny sensor enabled smart services. The related literature on green computing majorly focuses on a cover set approach that works efficiently for target coverage, but it is not applicable in case of area coverage. In this paper, we present a new variant of a cover set approach called a grouping and sponsoring aware IoT framework (GS-IoT) that is suitable for area coverage. We achieve non-overlapping coverage for an entire sensing region employing sectorial sensing. Non-overlapping coverage not only guarantees a sufficiently good coverage in case of large number of sensors deployed randomly, but also maximizes the life span of the whole network with appropriate scheduling of sensors. A deployment model for distribution of sensors is developed to ensure a minimum threshold density of sensors in the sensing region. In particular, a fast converging grouping (FCG) algorithm is developed to group sensors in order to ensure minimal overlapping. A sponsoring aware sectorial coverage (SSC) algorithm is developed to set off redundant sensors and to balance the overall network energy consumption. GS-IoT framework effectively combines both the algorithms for smart services. The simulation experimental results attest to the benefit of the proposed framework as compared to the state-of-the-art techniques in terms of various metrics for smart IoT environments including rate of overlapping, response time, coverage, active sensors, and life span of the overall network.
  13. Role of adenosine receptors in resveratrol-induced intraocular pressure lowering in rats with steroid-induced ocular hypertension
    Razali N, Agarwal R, Agarwal P, Kumar S, Tripathy M, Vasudevan S, et al.
    Clin Exp Ophthalmol, 2015 Jan-Feb;43(1):54-66.
    PMID: 24995479 DOI: 10.1111/ceo.12375
    BACKGROUND: Steroid-induced ocular hypertension is currently treated in the same way as primary open-angle glaucoma. However, the treatment is often suboptimal and is associated with adverse effects. We evaluated the oculohypotensive effects of topical trans-resveratrol in rats with steroid-induced ocular hypertension and involvement of adenosine receptors (AR) in intraocular pressure (IOP) lowering effect of trans-resveratrol.
    METHODS: The oculohypotensive effect of unilateral single-drop application of various concentrations of trans-resveratrol was first studied in oculonormotensive rats. Concentration with maximum effect was similarly studied in rats with steroid-induced ocular hypertension. Involvement of AR was studied by observing the alterations of IOP in response to trans-resveratrol after pretreating animals with AR subtype-specific antagonists. Additionally, we used computational methods, including 3D modelling, 3D structure generation and protein-ligand interaction, to determine the AR-trans-resveratrol interaction.
    RESULTS: All concentrations of trans-resveratrol produced significant IOP reduction in normotensive rat eyes. Maximum mean IOP reduction of 15.1% was achieved with trans-resveratrol 0.2%. In oculohypertensive rats, trans-resveratrol 0.2% produced peak IOP reduction of 25.2%. Pretreatment with A₁ antagonist abolished the oculohypotensive effect of trans-resveratrol. Pretreatment with A₃ and A₂A AR antagonists produced significant IOP reduction in both treated and control eyes, which was further augmented by trans-resveratrol application in treated eyes. Computational studies showed that trans-resveratrol has highest affinity for A₂B and A₁, followed by A2A and A₃ AR.
    CONCLUSION: Topically applied trans-resveratrol reduces IOP in rats with steroid-induced ocular hypertension. Trans-resveratrol-induced oculohypotension involves its agonistic activity at the A₁ AR.
    KEYWORDS: adenosine receptors; docking simulation; intraocular pressure; resveratrol; topical
  14. AgNO3 dependant modulation of glucose mediated respiration kinetics in Escherichia coli at different pH and temperature
    Afiqah RN, Paital B, Kumar S, Majeed AB, Tripathy M
    J. Mol. Recognit., 2016 11;29(11):544-554.
    PMID: 27406464 DOI: 10.1002/jmr.2554
    The inhibitory role of AgNO3 on glucose-mediated respiration in Escherichia coli has been investigated as a function of pH and temperature using Clark-type electrode, environmental scanning electron microscopy, and computational tools. In the given concentration of bacterial suspension (1 × 10(8)  CFU/ml), E. coli showed an increasing nonlinear trend of tetra-phasic respiration between 1-133 μM glucose concentration within 20 min. The glucose concentrations above 133 μM did not result any linear increment in respiration but rather showed a partial inhibition at higher glucose concentrations (266-1066 μM). In the presence of glucose, AgNO3 caused a concentration-dependent (47-1960 μM) inhibition of the respiration rate within 4 min of its addition. The respiration rate was the highest at pH 7-8 and then was decreased on either side of this pH range. The inhibitory action of AgNO3 upon bacterial respiration was the highest at 37 °C. The observations of the respiration data were well supported by the altered bacterial morphology as observed in electron microscopic study. Docking study indicated the AgNO3 binding to different amino acids of all respiratory complex enzymes in E. coli and thereby explaining its interference with the respiratory chain. Copyright © 2016 John Wiley & Sons, Ltd.
  15. A facile stereoselective synthesis of dispiro-indeno pyrrolidine/pyrrolothiazole-thiochroman hybrids and evaluation of their antimycobacterial, anticancer and AchE inhibitory activities
    Bharkavi C, Vivek Kumar S, Ashraf Ali M, Osman H, Muthusubramanian S, Perumal S
    Bioorg Med Chem, 2016 11 15;24(22):5873-5883.
    PMID: 27687968 DOI: 10.1016/j.bmc.2016.09.044
    A facile stereoselective synthesis of novel dispiro indeno pyrrolidine/pyrrolothiazole-thiochroman hybrids has been achieved by 1,3-dipolar cycloaddition of azomethine ylides, generated in situ from ninhydrin and sarcosine/thiaproline, on a series of 3-benzylidenethiochroman-4-ones. The synthesised compounds were screened for their antimycobacterial, anticancer and AchE inhibition activities. Compound 4l (IC50 1.07μM) has been found to exhibit the most potent antimycobacterial activity compared to cycloserine (12 times), pyrimethamine (37 times) and ethambutol (IC50 <1.56μM) and 6l (IC50=2.87μM) is more active than both cycloserine (4 times) and pyrimethamine (12 times). Three compounds, 4a, 6b and 6i, display good anticancer activity against CCRF-CEM cell lines. Compounds 6g and 4g display maximum AchE inhibitory activity with IC50 values of 1.10 and 1.16μmol/L respectively.
  16. Role of Antioxidants and Natural Products in Inflammation
    Arulselvan P, Fard MT, Tan WS, Gothai S, Fakurazi S, Norhaizan ME, et al.
    Oxid Med Cell Longev, 2016;2016:5276130.
    PMID: 27803762
    Inflammation is a comprehensive array of physiological response to a foreign organism, including human pathogens, dust particles, and viruses. Inflammations are mainly divided into acute and chronic inflammation depending on various inflammatory processes and cellular mechanisms. Recent investigations have clarified that inflammation is a major factor for the progression of various chronic diseases/disorders, including diabetes, cancer, cardiovascular diseases, eye disorders, arthritis, obesity, autoimmune diseases, and inflammatory bowel disease. Free radical productions from different biological and environmental sources are due to an imbalance of natural antioxidants which further leads to various inflammatory associated diseases. In this review article, we have outlined the inflammatory process and its cellular mechanisms involved in the progression of various chronic modern human diseases. In addition, we have discussed the role of free radicals-induced tissue damage, antioxidant defence, and molecular mechanisms in chronic inflammatory diseases/disorders. The systematic knowledge regarding the role of inflammation and its associated adverse effects can provide a clear understanding in the development of innovative therapeutic targets from natural sources that are intended for suppression of various chronic inflammations associated diseases.
  17. Anti-Inflammatory Potential of Ethyl Acetate Fraction of Moringa oleifera in Downregulating the NF-κB Signaling Pathway in Lipopolysaccharide-Stimulated Macrophages
    Arulselvan P, Tan WS, Gothai S, Muniandy K, Fakurazi S, Esa NM, et al.
    Molecules, 2016 Oct 31;21(11).
    PMID: 27809259
    In the present investigation, we prepared four different solvent fractions (chloroform, hexane, butanol, and ethyl acetate) of Moringa oleifera extract to evaluate its anti-inflammatory potential and cellular mechanism of action in lipopolysaccharide (LPS)-induced RAW264.7 cells. Cell cytotoxicity assay suggested that the solvent fractions were not cytotoxic to macrophages at concentrations up to 200 µg/mL. The ethyl acetate fraction suppressed LPS-induced production of nitric oxide and proinflammatory cytokines in macrophages in a concentration-dependent manner and was more effective than the other fractions. Immunoblot observations revealed that the ethyl acetate fraction effectively inhibited the expression of inflammatory mediators including cyclooxygenase-2, inducible nitric oxide synthase, and nuclear factor (NF)-κB p65 through suppression of the NF-κB signaling pathway. Furthermore, it upregulated the expression of the inhibitor of κB (IκBα) and blocked the nuclear translocation of NF-κB. These findings indicated that the ethyl acetate fraction of M. oleifera exhibited potent anti-inflammatory activity in LPS-stimulated macrophages via suppression of the NF-κB signaling pathway.
  18. Polymer-wrapped single-walled carbon nanotubes: a transformation toward better applications in healthcare
    Chik MW, Hussain Z, Zulkefeli M, Tripathy M, Kumar S, Majeed ABA, et al.
    Drug Deliv Transl Res, 2019 04;9(2):578-594.
    PMID: 29594914 DOI: 10.1007/s13346-018-0505-9
    Carbon nanotubes (CNTs) possess outstanding properties that could be useful in several technological, drug delivery, and diagnostic applications. However, their unique physical and chemical properties are hindered due to their poor solubility. This article review's the different ways and means of solubility enhancement of single-wall carbon nanotubes (SWNTs). The advantages of SWNTs over the multi-walled carbon nanotubes (MWNTs) and the method of non-covalent modification for solubility enhancement has been the key interest in this review. The review also highlights a few examples of dispersant design. The review includes some interesting utility of SWNTs being wrapped with polymer especially in biological media that could mediate proper drug delivery to target cells. Further, the use of wrapped SWNTs with phospholipids, nucleic acid, and amphiphillic polymers as biosensors is of research interest. The review aims at summarizing the developments relating to wrapped SWNTs to generate further research prospects in healthcare.
  19. Fulltext DNA shotgun sequencing analysis of Garcinia mangostana L. variety Mesta
    Abu Bakar S, Kumar S, Loke KK, Goh HH, Mohd Noor N
    Genom Data, 2017 Jun;12:118-119.
    PMID: 28516035 DOI: 10.1016/j.gdata.2017.05.001
    Mangosteen (Garcinia mangostana Linn.) is an ultra-tropical tree characterized by its unique dark purple fruits with white flesh. The xanthone-rich purple pericarp tissue contains valuable compounds with medicinal properties. Following previously reported genome sequencing of a common variety of mangosteen [1], we performed another whole genome sequencing of a commercially popular variety of this fruit species (var. Mesta) for comparative analysis of its genome composition. Raw reads of the DNA sequencing project were deposited to SRA database with the accession number SRX2709728.
  20. Study of structural properties and defects of Ni-doped SnO2 nanorods as ethanol gas sensors
    Inderan V, Arafat MM, Kumar S, Haseeb ASMA, Jiang ZT, Altarawneh M, et al.
    Nanotechnology, 2017 Jun 30;28(26):265702.
    PMID: 28593932 DOI: 10.1088/1361-6528/aa731c
    An ethanol gas sensor with enhanced sensor response was fabricated using Ni-doped SnO2 nanorods, synthesized via a simple hydrothermal method. It was found that the response (R = R 0/R g) of a 5.0 mol% Ni-doped SnO2 (5.0Ni:SnO2) nanorod sensor was 1.4 × 104 for 1000 ppm C2H5OH gas, which is about 13 times higher than that of pure SnO2 nanorods, (1.1 × 103) at the operating temperature of 450 °C. Moreover, for 50 ppm C2H5OH gas, the 5.0Ni:SnO2 nanorod sensor still recorded a significant response reading, namely 2.0 × 103 with a response time of 30 s and recovery time of 10 min. To investigate the effect of Ni dopant (0.5-5.0 mol%) on SnO2 nanorods, structural characterizations were demonstrated using field emission scanning electron microscopy, high-resolution transmission electron microscopy, Fourier transform infrared spectroscopy, x-ray diffraction (XRD) analysis, x-ray photoelectron spectroscopy and an ultraviolet-visible spectrometer. XRD results confirmed that all the samples consisted of tetragonal-shaped rutile SnO2 nanorods. It was found that the average diameter and length of the nanorods formed in 5.0Ni:SnO2 were four times smaller (∼6 and ∼35 nm, respectively) than those of the nanorods formed in pure SnO2 (∼25 and 150 nm). Interestingly, both samples had the same aspect ratio, ∼6. It is proposed that the high response of the 5.0Ni:SnO2 nanorod sensor can be attributed to the particle size, which causes an increase in the thickness of the charge depletion layer, and the presence of oxygen vacancies within the matrix of SnO2 nanorods.
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