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  1. Rezk H, Nassef AM, Inayat A, Sayed ET, Shahbaz M, Olabi AG
    Sci Total Environ, 2019 Mar 25;658:1150-1160.
    PMID: 30677979 DOI: 10.1016/j.scitotenv.2018.12.284
    Fossil fuel depletion and the environmental concerns have been under discussion for energy production for many years and finding new and renewable energy sources became a must. Biomass is considered as a net zero CO2 energy source. Gasification of biomass for H2 and syngas production is an attractive process. The main target of this research is to improve the production of hydrogen and syngas from palm kernel shell (PKS) steam gasification through defining the optimal operating parameters' using a modern optimization algorithm. To predict the gaseous outputs, two PKS models were built using fuzzy logic based on the experimental data sets. A radial movement optimizer (RMO) was applied to determine the system's optimal operating parameters. During the optimization process, the decision variables were represented by four different operating parameters. These parameters include; temperature, particle size, CaO/biomass ratio and coal bottom ash (CBA) with their operating ranges of (650-750 °C), (0.5-1 mm), (0.5-2) and wt% (0.02-0.10), respectively. The individual and interactive effects of different combinations were investigated on the production of H2 and syngas yield. The optimized results were compared with experimental data and results obtained from Response Surface Methodology (RSM) reported in literature. The obtained optimal values of the operating parameters through RMO were found 722 °C, 0.92 mm, 1.72 and 0.06 wt% for the temperature, particle size, CaO/biomass ratio and coal bottom ash, respectively. The results showed that syngas production was significantly improved as it reached 65.44 vol% which was better than that obtained in earlier studies.
  2. Zakaria MY, Sulong AB, Muhamad N, Raza MR, Ramli MI
    Mater Sci Eng C Mater Biol Appl, 2019 Apr;97:884-895.
    PMID: 30678979 DOI: 10.1016/j.msec.2018.12.056
    Titanium-ceramic composites are potential implant material candidates because of their unique mechanical properties and biocompatibility. This review focused on the latest advancement in processing of titanium-ceramic materials. Previously, titanium-ceramic incorporated using different coating techniques, i.e., plasma spraying and electrophoretic depositions, to enhance the biocompatibility of the implants. A major drawback in these coating methods is the growth of tissue at only the surface of the composite and might peel off over time. Recently, metal-ceramic composite was introduced via powder metallurgy method such as powder injection moulding. A porous structure can be obtained via powder metallurgy. Producing a porous titanium-ceramic structure would improve the mechanical properties, biocompatibility and tissue growth within the structure. Hence, further research needed to be done by considering the potential of powder injection moulding method which offer lower costs and more complex shapes for future implant.
  3. Sajjad Z, Gilani MA, Nizami AS, Bilad MR, Khan AL
    J Environ Manage, 2019 Dec 01;251:109618.
    PMID: 31563603 DOI: 10.1016/j.jenvman.2019.109618
    This paper aims to develop novel hydrophilic ionic liquid membranes using pervaporation for the recovery of biobutanol. Multiple polyvinyl alcohol (PVA) membranes based on three commercial ionic liquids with different loading were prepared for various experimental trials. The ionic liquids selected for the study include tributyl (tetradecyl) phosphonium chloride ([TBTDP][Cl]), tetrabutyl phosphonium bromide ([TBP][Br]) and tributyl methyl phosphonium methylsulphate ([TBMP][MS]). The synthesized membranes were characterized and tested in a custom-built pervaporation set-up. All ionic liquid membranes showed better results with total flux of 1.58 kg/m2h, 1.43 kg/m2h, 1.38 kg/m2h at 30% loading of [TBP][Br], [TBMP][MS] and [TBTDP][Cl] respectively. The comparison of ionic liquid membranes revealed that by incorporating [TBMP]MS to PVA matrix resulted in a maximum separation factor of 147 at 30 wt% loading combined with a relatively higher total flux of 1.43 kg/m2h. Density functional theory (DFT) calculations were also carried out to evaluate the experimental observations along with theoretical studies. The improved permeation properties make these phosphonium based ionic liquid a promising additive in PVA matrix for butanol-water separation under varying temperature conditions.
  4. Syed Soffian SS, Ahmad SB, Chan HK, Soelar SA, Abu Hassan MR, Ismail N
    PLoS One, 2019;14(10):e0223383.
    PMID: 31581261 DOI: 10.1371/journal.pone.0223383
    INTRODUCTION: While Kedah has recorded the highest prevalence of diabetes among all the states in Malaysia, the information on the practice and effectiveness of disease management in public health institutions remains limited. This study aimed to evaluate the management and glycemic control of patients with type-2 diabetes mellitus (T2DM) at the primary care level in Kedah.

    METHODS: All T2DM patients, who made at least one visit to any of the 58 public health clinics in Kedah during August 2016 and July 2017, were included in this study. The sample was selected from the National Diabetes Registry using the stratified random sampling method. The information on the demographic and clinical characteristics, laboratory findings and pharmacological treatment was gathered from medical records of patients. The differences in mean HbA1C levels across subgroups of each variable were tested using the general linear model. The evaluation of the appropriateness of treatment was performed based on the recommendations of the latest Clinical Practice Guidelines for T2DM.

    RESULTS: The patients (n = 23,557) were mainly female (63.4%), of Malay ethnicity (80.1%) and middle-aged (62.2%), with a mean duration of T2DM of 6.2±7.16 years. Only 15.6% of them had a HbA1C level <6.5%, and 28.6% did not have their HbA1C levels tested over the 12-month period. Yet, the underutilization of combination treatment (≥2 antidiabetic agents) and insulin in the patients with a poor glycemic control was evident. Retinopathy emerged as the most prevalent diabetes-related complication (12.6%). Along with those with a longer duration of T2DM, the patients who were younger, female and of Indian ethnicity were found to generally have a poorer glycemic control.

    CONCLUSION: This study discloses the suboptimal T2DM management at the primary care level in Kedah, which warrants a statewide plan for improvement.

  5. Gulzari UA, Khan S, Sajid M, Anjum S, Torres FS, Sarjoughian H, et al.
    PLoS One, 2019;14(10):e0222759.
    PMID: 31577809 DOI: 10.1371/journal.pone.0222759
    This paper presents the Hybrid Scalable-Minimized-Butterfly-Fat-Tree (H-SMBFT) topology for on-chip communication. Main aspects of this work are the description of the architectural design and the characteristics as well as a comparative analysis against two established indirect topologies namely Butterfly-Fat-Tree (BFT) and Scalable-Minimized-Butterfly-Fat-Tree (SMBFT). Simulation results demonstrate that the proposed topology outperforms its predecessors in terms of performance, area and power dissipation. Specifically, it improves the link interconnectivity between routing levels, such that the number of required links isreduced. This results into reduced router complexity and shortened routing paths between any pair of communicating nodes in the network. Moreover, simulation results under synthetic as well as real-world embedded applications workloads reveal that H-SMBFT can reduce the average latency by up-to35.63% and 17.36% compared to BFT and SMBFT, respectively. In addition, the power dissipation of the network can be reduced by up-to33.82% and 19.45%, while energy consumption can be improved byup-to32.91% and 16.83% compared to BFT and SMBFT, respectively.
  6. Khairul-Anuar MA, Mazumdar P, Lau SE, Tan TT, Harikrishna JA
    3 Biotech, 2019 Oct;9(10):371.
    PMID: 31588395 DOI: 10.1007/s13205-019-1898-y
    Isolation of high-quality RNA from Dendrobium flowers is challenging because of the high levels of pigment, polysaccharides, and polyphenols. In the present study, an efficient CTAB method for RNA extraction from the pigment-rich flowers of Dendrobium was optimised. The optimised method yielded high quantities of RNA (10.1-12.9 µg/g). Spectrophotometric values of A260/280 in the range of 2.2 to 2.4 and A260/230 values of 2.0 suggested that the isolated RNA was free of polyphenols, polysaccharides, and protein contaminants. RNA integrity numbers determined by microfluidics were in the range of 7.9-8.9 indicative of intact RNA. In the improved method, the addition of 3 M NaCl and 3% PVP-10 in the extraction buffer, followed by an incubation period of 45 min at 65 °C, eliminated most of the polysaccharides, polyphenolic compounds, and denatured protein. Extraction with phenol:chloroform:isoamyl alcohol (125:24:1) effectively removed pigments from the aqueous phase, while the precipitation of RNA with lithium chloride minimised the co-precipitation of protein, DNA, and polysaccharide and resulted in the extraction of high quality of RNA. The suitability of the RNA for downstream processing was confirmed via RT-PCR amplification of Chalcone synthase gene from cDNA prepared from RNA isolated from different developmental stages of the flower of a Dendrobium hybrid. The present method will be highly useful for the isolation of RNA from pigment, polyphenol, and polysaccharide-rich plant tissues.
  7. Saleem H, Htar TT, Naidu R, Nawawi NS, Ahmad I, Ashraf M, et al.
    Food Chem Toxicol, 2019 Jan;123:363-373.
    PMID: 30419323 DOI: 10.1016/j.fct.2018.11.016
    We investigated into the effects of methanol and dichloromethane extracts from aerial and roots of Filago germanica (L.) Huds (Astearaceae) on key enzymes (cholinesterases, α-glucosidase and urease), antioxidant capabilities, cytotoxic potential and secondary metabolomics profile. Total phenolic and flavonoids were determined by spectrophotometric technique and secondary metabolites composition by UHPLC-MS. Antioxidant activities were assessed employing free radical scavenging, ferric reducing power and phosphomolybdenum assays. The cell-toxicity was evaluated by MTT assay against breast (MCF-7, MDA-MB-231), cervix (CaSki) and prostate (DU-145) cancers. Overall, methanol extracts were found to have higher total bioactive contents and antioxidant potential. UHPLC-MS analysis revealed significant variation in the secondary metabolites in the methanol extracts. The most common derivatives belong to seven groups i.e. alkaloids, benzoic acids, flavones, flavonols, flavan-3-ols, terpenoids and saponins. The major polyphenolic compounds were found to be kampferol, robinin, luteolin, ferulic acid, benzoic acid and salicylic acid. All the extracts showed moderate cholinesterases inhibition, whereas methanol extracts exhibited highest urease inhibition and all extracts presented a relatively high inhibition against α-glucosidase. Similarly, all extracts showed strong to moderate cytotoxicity with IC50 values ranging from 53.02 to 382.7 μg/mL. Overall, results have suggested F. germanica to be a lead source for novel natural products.
  8. Teah YF, Abduraman MA, Amanah A, Adenan MI, Sulaiman SF, Tan ML
    Food Chem Toxicol, 2017 Sep;107(Pt A):293-301.
    PMID: 28689918 DOI: 10.1016/j.fct.2017.07.011
    Elephantopus scaber Linn and its major bioactive component, deoxyelephantopin are known for their medicinal properties and are often reported to have various cytotoxic and antitumor activities. This plant is widely used as folk medicine for a plethora of indications although its safety profile remains unknown. Human ether-a-go-go-related gene (hERG) encodes the cardiac IKr current which is a determinant of the duration of ventricular action potentials and QT interval. The hERG potassium channel is an important antitarget in cardiotoxicity evaluation. This study investigated the effects of deoxyelephantopin on the current, mRNA and protein expression of hERG channel in hERG-transfected HEK293 cells. The hERG tail currents following depolarization pulses were insignificantly affected by deoxyelephantopin in the transfected cell line. Current reduction was less than 40% as compared with baseline at the highest concentration of 50 μM. The results were consistent with the molecular docking simulation and hERG surface protein expression. Interestingly, it does not affect the hERG expression at both transcriptional and translational level at most concentrations, although higher concentration at 10 μM caused protein accumulation. In conclusion, deoxyelephantopin is unlikely a clinically significant hERG channel and Ikr blocker.
  9. Khan A, Mushtaq MH, Ahmad MUD, Nazir J, Farooqi SH, Khan A
    Virus Res, 2017 08 15;240:56-63.
    PMID: 28757141 DOI: 10.1016/j.virusres.2017.07.022
    BACKGROUND: A widespread epidemic of equine influenza (EI) occurred in nonvaccinated equine population across multiple districts in Khyber Pakhtunkhwa Province of Pakistan during 2015-2016.

    OBJECTIVES AND METHODS: An epidemiological surveillance study was conducted from Oct 2015 to April 2016 to investigate the outbreak. EI virus strains were isolated in embryonated eggs from suspected equines swab samples and were subjected to genome sequencing using M13 tagged segment specific primers. Phylogenetic analyses of the nucleotide sequences were concluded using Geneious. Haemagglutinin (HA), Neuraminidase (NA), Matrix (M) and nucleoprotein (NP) genes nucleotide and amino acid sequences of the isolated viruses were aligned with those of OIE recommended, FC-1, FC-2, and contemporary isolates of influenza A viruses from other species.

    RESULTS: HA and NA genes amino acid sequences were very similar to Tennessee/14 and Malaysia/15 of FC-1 and clustered with the contemporary isolates recently reported in the USA. Phylogenetic analysis showed that these viruses were mostly identical (with 99.6% and 97.4% nucleotide homology) to, and were reassortants containing chicken/Pakistan/14 (H7N3) and Canine/Beijing/10 (H3N2) like M and NP genes. Genetic analysis indicated that A/equine/Pakistan/16 viruses were most probably the result of several re-assortments between the co-circulating avian and equine viruses, and were genetically unlike the other equine viruses due to the presence of H7N3 or H3N2 like M and NP genes.

    CONCLUSION: Epidemiological data analysis indicated the potential chance of mixed, and management such as mixed farming system by keeping equine, canine and backyard poultry together in confined premises as the greater risk factors responsible for the re-assortments. Other factors might have contributed to the spread of the epidemic, including low awareness level, poor control of equine movements, and absence of border control disease strategies.

  10. C W Ahmad CWI, Awang Lukman K, Raja Omar RM, Jeffree MS
    Risk Manag Healthc Policy, 2021;14:803-808.
    PMID: 33658876 DOI: 10.2147/RMHP.S278786
    Background and Aim: Healthcare workers (HCWs) routinely experience occupational blood and body fluid exposure (OBBE), including percutaneous injury and splash exposure to non-intact skin. The objective of this study was to determine the prevalence of OBBE and identify associated risk factors.

    Methods: A cross-sectional study was performed on 334 HCWs at 9 workstations. Data were collected with a self-administered questionnaire that consisted of four parts: sociodemographic variables, work-related information, knowledge about needle stick and sharps injury and splash exposure, and information regarding previous OBBE incidents. The data were analyzed by SPSS version 22.0 software.

    Findings: The prevalence of OBBE was 25.1% (95% confidence interval: 20.6-30.2), mostly due to percutaneous injuries, which were not reported to authorities. The highest proportions were among nurses and those working in the medical ward. Needle recapping practices were associated with almost a four-times higher risk of OBBE compared to no-recapping practices. HCWs who did not have any infection prevention training had a three-times higher risk of OBBE.

    Conclusion: Factors associated with OBBE are unsafe work practices, inadequate infection prevention training, and lack of knowledge regarding blood-borne infection. There is a need for more training and increased awareness about the risks of OBBE to reduce unsafe practices.

  11. Ahmad AA, Ubaidah Mustapa Kamal MA, Ruslan SR, Abdullah S, Ahmad AR
    J Shoulder Elbow Surg, 2020 Nov;29(11):2319-2325.
    PMID: 32499198 DOI: 10.1016/j.jse.2020.03.003
    BACKGROUND: Fixation of clavicle fractures has now become a more popular option as it provides better outcome compared with conservative management. Wide-awake local anesthesia no tourniquet (WALANT) has been effectively used in plating of distal radius and olecranon fractures. This paper expands the usage of WALANT into the shoulder girdle, namely plating of the clavicle that has not been described. The operation is typically performed under general anesthesia.

    METHODS: We report a case series of 16 patients who successfully underwent fixation of the clavicle under the wide-awake technique. The clavicle fractures were grouped under the AO Fracture Classification. The WALANT solution comprised 1% lidocaine, 1:100,000 epinephrine, and 10:1 sodium bicarbonate. A total of 40 mL was injected in each patient with 10 mL subcutaneously along the clavicle followed by 30 mL subperiosteally at multiple intervals and directions.

    RESULTS: The Numerical Pain Rating Score was 0 during WALANT injection and during surgery except for 2 patients with Numerical Pain Rating Scores of 1 and 2, respectively, during reduction.

    CONCLUSION: We conclude that clavicle plating under WALANT is a good alternative option of anesthesia.

  12. Anuar MZA, Salleh WMNHW, Khamis S, Nafiah MA, Mat Said Z
    Nat Prod Res, 2021 Feb;35(3):508-511.
    PMID: 31266357 DOI: 10.1080/14786419.2019.1636245
    The chemical composition of the essential oil from the leaves of Alseodaphne perakensis (Gamble) Kosterm (Lauraceae) growing in Perak, Malaysia was investigated for the first time. The essential oil was obtained by hydrodistillation and fully characterized by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). A total of 37 components (90.9 ± 2.5%) were successfully identified in the essential oil which were characterized by high proportions of bicyclogermacrene (15.8 ± 0.5%), δ-cadinene (11.7 ± 0.2%), γ-cadinene (6.3 ± 0.4%), and aromadendrene (5.6 ± 0.5%).
  13. Khalid H, Hashim SJ, Ahmad SMS, Hashim F, Chaudhary MA
    Sensors (Basel), 2021 Feb 18;21(4).
    PMID: 33670675 DOI: 10.3390/s21041428
    The development of the industrial Internet of Things (IIoT) promotes the integration of the cross-platform systems in fog computing, which enable users to obtain access to multiple application located in different geographical locations. Fog users at the network's edge communicate with many fog servers in different fogs and newly joined servers that they had never contacted before. This communication complexity brings enormous security challenges and potential vulnerability to malicious threats. The attacker may replace the edge device with a fake one and authenticate it as a legitimate device. Therefore, to prevent unauthorized users from accessing fog servers, we propose a new secure and lightweight multi-factor authentication scheme for cross-platform IoT systems (SELAMAT). The proposed scheme extends the Kerberos workflow and utilizes the AES-ECC algorithm for efficient encryption keys management and secure communication between the edge nodes and fog node servers to establish secure mutual authentication. The scheme was tested for its security analysis using the formal security verification under the widely accepted AVISPA tool. We proved our scheme using Burrows Abdi Needham's logic (BAN logic) to prove secure mutual authentication. The results show that the SELAMAT scheme provides better security, functionality, communication, and computation cost than the existing schemes.
  14. Zainuddin MF, Fai CK, Ariff AB, Rios-Solis L, Halim M
    Microorganisms, 2021 Jan 27;9(2).
    PMID: 33513696 DOI: 10.3390/microorganisms9020251
    The production of lipids from oleaginous yeasts involves several stages starting from cultivation and lipid accumulation, biomass harvesting and finally lipids extraction. However, the complex and relatively resistant cell wall of yeasts limits the full recovery of intracellular lipids and usually solvent extraction is not sufficient to effectively extract the lipid bodies. A pretreatment or cell disruption method is hence a prerequisite prior to solvent extraction. In general, there are no recovery methods that are equally efficient for different species of oleaginous yeasts. Each method adopts different mechanisms to disrupt cells and extract the lipids, thus a systematic evaluation is essential before choosing a particular method. In this review, mechanical (bead mill, ultrasonication, homogenization and microwave) and nonmechanical (enzyme, acid, base digestions and osmotic shock) methods that are currently used for the disruption or permeabilization of oleaginous yeasts are discussed based on their principle, application and feasibility, including their effects on the lipid yield. The attempts of using conventional and "green" solvents to selectively extract lipids are compared. Other emerging methods such as automated pressurized liquid extraction, supercritical fluid extraction and simultaneous in situ lipid recovery using capturing agents are also reviewed to facilitate the choice of more effective lipid recovery methods.
  15. Ranjith FH, Muhialdin BJ, Yusof NL, Mohammed NK, Miskandar MH, Hussin ASM
    Plants (Basel), 2021 Feb 03;10(2).
    PMID: 33546183 DOI: 10.3390/plants10020285
    BACKGROUND: the antagonism activity of lactic acid bacteria metabolites has the potential to prevent fungal growth on mango.

    METHODS: the potential of developing natural disinfectant while using watermelon rinds (WR), pineapple (PP), orange peels (OP), palm kernel cake (PKC), and rice bran (RB), via lacto-fermentation was investigated. The obtained lactic acid bacteria (LAB) metabolites were then employed and the in vitro antifungal activity toward five spoilage fungi of mango was tested through liquid and solid systems. Besides, the effect of the produced disinfectant on the fungal growth inhibition and quality of mango was investigated.

    RESULTS: the strains Lactobacillus plantarum ATCC8014 and Lactobacillus fermentum ATCC9338 growing in the substrates PKC and PP exhibited significantly higher in vitro antifungal activity against Colletotrichum gloeosporioides and Botryodiplodia theobromae as compared to other tested LAB strains and substrates. The in-situ results demonstrated that mango samples that were treated with the disinfectant produced from PKC fermented with L. plantarum and L. fermentum had the lowest disease incidence and disease severity index after 16 days shelf life, as well as the lowest conidial concentration. Furthermore, PKC that was fermented by L. fermentum highly maintained the quality of the mango.

    CONCLUSIONS: lactic acid fermentation of PKC by L. fermentum demonstrated a high potential for use as a natural disinfectant to control C. gloeosporioides and B. theobromae on mango.

  16. Tew MM, Hatah E, Arif F, Abdul Wahid MA, Makmor-Bakry M, Abdul Maulad KN
    J Pharm Policy Pract, 2021 Feb 24;14(1):24.
    PMID: 33627199 DOI: 10.1186/s40545-021-00308-9
    BACKGROUND: Minor ailments are defined as common, self-limiting, or uncomplicated conditions that may be diagnosed and managed without a medical intervention. Previous studies reported that pharmacists were able to help patients self-manage minor ailments that led to a reduction of health care burden in other facilities. Nevertheless, public access to community pharmacy and other health care facilities offering services for minor ailments has not yet been explored in Malaysia. Hence, this study aims to determine population access to the above-mentioned services.

    METHOD: According to the reported practice address in 2018, the spatial distribution of health care facilities was mapped and explored using the GIS mapping techniques. The density of health care facilities was analyzed using thematic maps with hot spot analysis. Population to facility ratio was calculated using the projection of the population growth based on 2010 census data, which was the latest available in the year of analysis.

    RESULTS: The study included geographical mapping of 7051 general practitioner clinics (GPC), 3084 community pharmacies (CP), 139 public general hospitals (GHs) and 990 public primary health clinics (PHC). The health care facilities were found to be highly dense in urban areas than in the rural ones. There were six districts that had no CP, 2 had no GPC, and 11 did not have both. The overall ratio of GPC, CP, GH, and PHC to the population was 1:4228, 1:10,200, 1:223,619 and 1:31,397, respectively. Should the coverage for minor ailment services in public health care clinics be extended to community pharmacies, the ratio of facilities to population for each district would be better with 1:4000-8000.

    CONCLUSIONS: The distribution of health care facilities for minor ailment management in Malaysia is relatively good. However, if the scheme for minor ailments were available to community pharmacies, then the patients' access to minor ailments services would be further improved.

  17. Al-Kumaim NH, Alhazmi AK, Ramayah T, Shabbir MS, Gazem NA
    Front Psychol, 2021;12:637808.
    PMID: 33643168 DOI: 10.3389/fpsyg.2021.637808
    Value Co-Creation (VCC) plays a major role in engaging knowledgeable individuals in a community via innovation, problem solving, and new service/product development. This study investigates the personal factors that influence individuals' engagement in value co-creation in Higher Education Institutions (HEIs) through the use of online platforms. Some higher education institutions have successfully established or used appropriate online platforms, such as online forums, web applications, and mobile applications to engage their community in ideation or crowdsourcing as a part of the value co-creation process. On the other hand, some HEIs have failed to engage their community in value co-creation activities, and even if they managed to engage some individuals in value co-creation once, they failed to sustain these individuals' engagement in value co-creation using online platforms. Using the Stimulus Organism Response (S-O-R) framework, this study examines the relationship between relevant personal factors (commitment and knowledge self-efficacy) and other motivational factors that provide perceived benefits with value co-creation engagement. Data was collected from 308 respondents at five Malaysian research universities. The software analysis tool Smart PLS is used for data analysis and validation. The results demonstrate that personal factors and perceived benefits as a motivational factor has a significant effect on individual engagement in value co-creation. However, the significance of these findings varies from one individual to another. The implications of these findings are discussed.
  18. Roslan MA, Shafie A, Ngui R, Lim YA, Sulaiman WY
    J Am Mosq Control Assoc, 2013 Dec;29(4):328-36.
    PMID: 24551965
    Dengue is a serious public health problem in Malaysia. The aim of this study was to compare the vertical infestation of Aedes population in 2 apartments in Kuala Lumpur with different status of dengue incidence (i.e., high-dengue-incidence area and area with no reported dengue cases). The study was also conducted to assess the relationship between environmental factors such as rainfall, temperature, and humidity and Aedes population that may influence Aedes infestation. Surveillance with a mosquito larvae trapping device was conducted for 28 continuous weeks (January to July 2012) in Vista Angkasa (VA) and Inderaloka (IL) apartments located in Kuala Lumpur, Malaysia. The results indicated that both Aedes spp. could be found from ground to higher floor levels of the apartments, with Aedes aegypti being more predominant than Ae. albopictus. Data based on mixed and single breeding of Aedes spp. on different floors did not show any significant difference. Both rainfall (R3; i.e., the amount of rainfall collected during the previous 3 wk before the surveillance period began) and RH data showed significant relationship with the number of Aedes larvae collected in VA and IL. No significant difference was found between the numbers of Aedes larvae in both study areas as well as maximum and minimum temperatures. Results also indicated adaptations of Ae. aegypti to the ecosystem at each elevation of high-rise buildings, with Ae. albopictus staying inside of apartment units.
  19. Ahmed D, Anwar A, Khan AK, Ahmed A, Shah MR, Khan NA
    AMB Express, 2017 Nov 21;7(1):210.
    PMID: 29164404 DOI: 10.1186/s13568-017-0515-x
    Biofilm formation by pathogenic bacteria is one of the major threats in hospital related infections, hence inhibiting and eradicating biofilms has become a primary target for developing new anti-infection approaches. The present study was aimed to develop novel antibiofilm agents against two Gram-positive bacteria; Staphylococcus aureus (ATCC 43300) and Streptococcus mutans (ATCC 25175) using gold nanomaterials conjugated with 3-(diphenylphosphino)propionic acid (Au-LPa). Gold nanomaterials with different sizes as 2-3 nm small and 9-90 nm (50 nm average size) large were stabilized by LPa via different chemical synthetic strategies. The nanomaterials were fully characterized using atomic force microscope (AFM), transmission electron microscope, ultraviolet-visible absorption spectroscopy, and Fourier transformation infrared spectroscopy. Antibiofilm activity of Au-LPa nanomaterials was tested using LPa alone, Au-LPa and unprotected gold nanomaterials against the both biofilm-producing bacteria. The results showed that LPa alone did not inhibit biofilm formation to a significant extent below 0.025 mM, while conjugation with gold nanomaterials displayed manifold enhanced antibiofilm potential against both strains. Moreover, it was also observed that the antibiofilm potency of the Au-LPa nanomaterials varies with size variations of nanomaterials. AFM analysis of biofilms further complemented the assay results and provided morphological aspects of the antibiofilm action of Au-LPa nanomaterials.
  20. Anwar A, Ting ELS, Anwar A, Ain NU, Faizi S, Shah MR, et al.
    AMB Express, 2020 Feb 03;10(1):24.
    PMID: 32016777 DOI: 10.1186/s13568-020-0960-9
    Acanthamoeba spp. are the causative agent of Acanthamoeba keratitis and granulomatous amoebic encephalitis (GAE). The current options to treat Acanthamoeba infections have limited success. Silver nanoparticles show antimicrobial effects and enhance the efficacy of their payload at the specific biological targets. Natural folk plants have been widely used for treating diseases as the phytochemicals from several plants have been shown to exhibit amoebicidal effects. Herein, we used natural products of plant or commercial sources including quercetin (QT), kolavenic acid (PGEA) isolated from plant extracts of Polyalthia longifolia var pendula and crude plant methanolic extract of Caesalpinia pulcherrima (CPFLM) as antiacanthamoebic agents. Furthermore, these plant-based materials were conjugated with silver nanoparticles (AgNPs) to determine the effects of the natural compounds and their nanoconjugates against a clinical isolate of A. castellanii from a keratitis patient (ATCC 50492) belonging to the T4 genotype. The compounds were conjugated with AgNPs and characterized by using ultraviolet visible spectrophotometry and atomic force microscopy. Quercetin coated silver nanoparticles (QT-AgNPs) showed characteristic surface plasmon resonance band at 443 nm and the average size distribution was found to be around 45 nm. The natural compounds alone and their nanoconjugates were tested for the viability of amoebae, encystation and excystation activity against A. castellanii. The natural compounds showed significant growth inhibition of A. castellanii while QT-AgNPs specifically exhibited enhanced antiamoebic effects as well as interrupted the encystation and excystation activity of the amoebae. Interestingly, these compounds and nanoconjugates did not exhibit in vitro cytotoxic effects against human cells. Plant-based compounds and extracts could be an interesting strategy in development of alternative therapeutics against Acanthamoeba infections.
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