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  1. Kesan gabungan aktiviti guna tanah dan perubahan musim terhadap kualiti sumber air: kajian kes di Terusan Utara, Kedah
    Mohd. Suhaimi Ahmad, Muhammad Ridwan Fahmi, Mustaqqim Abdul Rahim, Naimah Ibrahim
    Sains Malaysiana, 2016;45:1857-1867.
    Suatu kajian untuk menilai kesan gabungan aktiviti guna tanah dan perubahan musim terhadap kualiti sumber air telah dijalankan di Terusan Utara, Kedah. Kajian ini dijalankan di lima stesen terpilih selama 12 bulan berdasarkan Indeks Kualiti Air (WQI) dan Piawaian Interim Kualiti Air Kebangsaan (INWQS). Kajian mendapati kualiti air di Terusan Utara berada pada Kelas III dan berlaku peningkatan kualiti air dari hulu ke hilir. Hampir semua stesen berpotensi sebagai punca pencemaran berdasarkan aktiviti guna tanah terutamanya di Pelubang, Jitra serta Tunjang. Kajian menunjukkan terdapat perbezaan yang signifikan ketika perubahan musim pada DO, TSS serta BOD, namun tidak pada ammonia, pH dan COD. Secara amnya, kombinasi aktiviti guna tanah dan perubahan musim boleh mempengaruhi atau memberi kesan terhadap kualiti sumber air. Oleh itu, tindakan segera perlu dilakukan untuk mengawal punca pencemaran bagi memastikan kualiti sumber air di Terusan Utara kekal terpelihara.
  2. Non-seismic geophysical prospecting model of beiya gold mine in western yunnan province
    Jian Yang, Qiao Wang, Shengxian Liang, Jing Guo, Muhammad Aqeel Ashraf
    Sains Malaysiana, 2017;46:2149-2162.
    According to the basic rules and characteristics of the gold-polymetallic deposits of Beiya gold mine area in terms of mineralization and ore controlling, it is concluded that skarn deposit is the main ore deposit type in this area and the geological conditions are analyzed by the statistics of the physical parameters. Then, the tectonic, rocks, stratum, ore geophysical models have been treated by the forward modeling numerical simulation and the results are analyzed comprehensively. Based on the forward modeling results, combined with the relevant physical differences, the principle and exploration method test and research for the comprehensive geophysical exploration technology has been carried out, covering the induced polarization and magnetic prospecting for the ore body as well as the indirect geophysical exploration method by means of plane gravity data, audio-magnetotelluric sounding for rock mass and tectonics, the mineralization mode-physical forward modeling - geophysical exploration mode has been established and good results have been achieved. Therefore, a location forecast method has been put forward for the concealed skarn type Fe-Au deposit which is adaptive to the mineralized geological background of Beiya and other similar areas.
  3. Synthesis and binding behaviour of new isomers of bis-thiourea
    Imran Fakhar, Bohari Muhammad Yamin, Sahilah Abdul Mutalib, Siti Aishah Hasbullah
    Sains Malaysiana, 2018;47:1199-1208.
    The two new symmetrical bis-thiourea compounds, 2,2’-[{(terephthaloylbis(azanediyl)bis (carbonothioyl)bis(azanediyl)}
    bis(4-methylpentanoicacid)] 1A and 2,2’-[{(isophthaloylbis (azanediyl)bis(carbonothioyl)bis(azanediyl)}bis(4-
    methylpentanoic acid)] 1B have been synthesized by reacting terephthaloyl/isophthaloyl chloride and L-leucine in high
    yields. Newly synthesized bis-thiourea derivatives were characterized using FTIR, 1D NMR, 2D NMR, MS spectrometry and
    Elemental analysis. Their binding properties with various cations were also carried out using UV-vis titration experiments.
    Both isomers exhibited effective binding against Ag+, Cu2+, Ni2+, Hg2+, Pb2+, Fe2+, and Fe3+ in the presence of other cations,
    such as Na+, Co2+, Cd2+, Zn2+, Mn2+, Mg2+, Ca2+, Sn2+, and Al3+. Stoichiometries of the host-guest complexation for both
    isomers were found to be 1:4 by plotting molar-ratio curves. Pearson Product moment correlation coefficient was in the
    range of 0.83-0.99 and nonlinear regression equation was used to calculate dissociation constant (Kd
    ). Both compounds
    displayed weak antibacterial activities against gram-positive and gram negative bacteria. Cytotoxicity testing on CCD841
    Normal human colon epithelial cell line showed that both compounds are non-toxic, with an IC50 value of 1.50 mg/mL.
  4. Green synthesis of selenium-N-heterocyclic carbene compounds: Evaluation of antimicrobial and anticancer potential
    Kamal A, Nazari V M, Yaseen M, Iqbal MA, Ahamed MBK, Majid ASA, et al.
    Bioorg Chem, 2019 09;90:103042.
    PMID: 31226469 DOI: 10.1016/j.bioorg.2019.103042
    Three benzimidazolium salts (III-V) and respective selenium adducts (VI-VIII) were designed, synthesized and characterized by various analytical techniques (FT-IR and NMR 1H, 13C). Selected salts and respective selenium N-Heterocyclic carbenes (selenium-NHC) adducts were tested in vitro against Cervical Cancer Cell line (Hela), Breast Adenocarcinoma cell line (MCF-7), Retinal Ganglion Cell line (RGC-5) and Mouse Melanoma Cell line (B16F10) using MTT assay and the results were compared with standard drug 5-Fluorouracil. Se-NHC compounds and azolium salts showed significant anticancer potential. Molecular docking studies of compounds (VI, VII and VIII) showed strong binding energies and ligand affinity toward following angiogenic factors: VEGF-A (vascular endothelial growth factor A), EGF (human epidermal growth factor), HIF (Hypoxia-inducible factor) and COX-1 (Cyclooxygenase-1) suggesting that the anticancer activity of adducts (VI, VII and VIII) may be due to their strong anti-angiogenic effect. In addition, compounds III-VIII were screened for their antibacterial and antifungal potential. Adduct VI was found to be potent anti-fungal agent against A. Niger with zone of inhibition (ZI) value 27.01 ± 0.251 mm which is better than standard drug Clotrimazole tested in parallel.
  5. Evaluation performance of time series approach for forecasting air pollution index in Johor, Malaysia
    Nur Haizum Abd Rahman, Muhammad Hisyam Lee, Suhartono, Mohd Talib Latif
    Sains Malaysiana, 2016;45:1625-1633.
    The air pollution index (API) has been recognized as one of the important air quality indicators used to record the
    correlation between air pollution and human health. The API information can help government agencies, policy makers
    and individuals to prepare precautionary measures in order to eliminate the impact of air pollution episodes. This study
    aimed to verify the monthly API trends at three different stations in Malaysia; industrial, residential and sub-urban areas.
    The data collected between the year 2000 and 2009 was analyzed based on time series forecasting. Both classical and
    modern methods namely seasonal autoregressive integrated moving average (SARIMA) and fuzzy time series (FTS) were
    employed. The model developed was scrutinized by means of statistical performance of root mean square error (RMSE).
    The results showed a good performance of SARIMA in two urban stations with 16% and 19.6% which was more satisfactory
    compared to FTS; however, FTS performed better in suburban station with 25.9% which was more pleasing compared
    to SARIMA methods. This result proved that classical method is compatible with the advanced forecasting techniques in
    providing better forecasting accuracy. Both classical and modern methods have the ability to investigate and forecast
    the API trends in which can be considered as an effective decision-making process in air quality policy.
  6. Sifat kinetik dan isoterma penjerapan formaldehid ke atas komposit serbuk serat kelapa sawit-TiO2
    Nor Rahafza Abdul Manap, Roslinda Shamsudin, Mohd Norhafsam MaghpoR, Muhammad Azmi Abdul Hamid, Azman Jalar
    Sains Malaysiana, 2017;46:953-965.
    Sifat isoterma dan kinetik penjerapan formaldehid ke atas komposit serbuk serat kelapa sawit-TiO2 yang melibatkan sistem gas-pepejal adalah dikaji. Komposit serbuk serat kelapa sawit-TiO2 dihasilkan dengan mencampurkan serbuk kelapa sawit dan serbuk TiO2 dengan nisbah 8:2 menggunakan teknik pengisaran mekanik. Pengujian dijalankan di dalam kebuk ujian dengan komposit serbuk kelapa sawit-TiO2 dibiarkan untuk menjerap dan mengurangkan nilai kepekatan formaldehid secara pasif. Didapati nilai penjerapan maksima dan sifat kinetik penjerapan bergantung kepada kepekatan awal formaldehid. Kepekatan awal, Ci, 2.1 ppm dan 0.5 ppm masing-masing diwakili oleh pseudo-tertib pertama dan pseudo tertib kedua, manakala Ci = 0.75 dan 0.9 ppm diwakili oleh model Elovich. Isoterma penjerapan formaldehid diwakili oleh isoterma Freundlich dengan nilai korelasi tertinggi R2 = 0.9397 berbanding nilai korelasi isoterma Langmuir (R2 = 0.8692) dan isoterma Temkin (R2 = 0.8756). Parameter keseimbangan, 0
  7. Enhanced photodegradation of phenol by ZnO nanoparticles synthesized through sol-gel method
    Nikathirah Yusoff, Li-ngee Ho, Soon-an Ong, Yee-shian Wong, Wanfadhilah Khalik, Muhammad Fahmi Ridzwan
    Sains Malaysiana, 2017;46:2507-2514.
    Zinc oxide (ZnO) utilization in advanced oxidation process (AOP) via solar-photocatalytic process was a promising method for alternative treating wastewater containing phenol. The ZnO photocatalyst semiconductor was synthesized by sol-gel method. The morphology of the ZnO nanostructures was observed by using scanning electron microscope (SEM) and the crystallite phase of the ZnO was confirmed by x-ray diffraction (XRD). The objective of this study was to synthesis ZnO nanoparticles through a sol-gel method for application as a photocatalyst in the photodegradation of phenol under solar light irradiation. The photodegradation rate of phenol increased with the increasing of ZnO loading from 0.2 until 1.0 g. Only 2 h were required for synthesized ZnO to fully degrade the phenol. The synthesized ZnO are capable to totally degrade high initial concentration up until 45 mg L-1 within 6 h of reaction time. The photodegradation of phenol by ZnO are most favoured under the acidic condition (pH3) where the 100% removal achieved after 2 h of reaction. The mineralization of phenol was monitored through chemical oxygen demand (COD) reduction and 92.6% or removal was achieved. This study distinctly utilized natural sunlight as the sole sources of irradiation which safe, inexpensive; to initiate the photocatalyst for degradation of phenol.
  8. Load forecasting using combination model of multiple linear regression with neural network for Malaysian city
    Nur Arina Bazilah Kamisan, Muhammad Hisyam Lee, Suhartono Suhartono, Abdul Ghapor Hussin, Yong Zulina Zubairi
    Sains Malaysiana, 2018;47:419-426.
    Forecasting a multiple seasonal data is differ from a usual seasonal data since it contains more than one cycle in a
    data. Multiple linear regression (MLR) models have been used widely in load forecasting because of its usefulness in the
    forecast a linear relationship with other factors but MLR has a disadvantage of having difficulties in modelling a nonlinear
    relationship between the variables and influencing factors. Neural network (NN) model, on the other hand, is a good
    model for modelling a nonlinear data. Therefore, in this study, a combination of MLR and NN models has proposed this
    combination to overcome the problem. This hybrid model is then compared with MLR and NN models to see the performance
    of the hybrid model. RMSE is used as a performance indicator and a proposed graphical error plot is introduce to see the
    error graphically. From the result obtained this model gives a better forecast compare to the other two models.
  9. 5-aminolevulinic acid induces regulation in growth, yield and physiobiochemical characteristics of wheat under water stress
    Nudrat Aisha Akram, Shamim Kausar, Naila Farid, Muhammad Ashraf, Muhammad Ashraf, Fahad Al-Qurainy
    Sains Malaysiana, 2018;47:661-670.
    The production of wheat crop is below average in many regions of the world which is ascribed to adverse environmental
    conditions including drought stress. The present study was conducted to appraise the beneficial role of exogenouslyapplied
    5-aminolevulinic acid (ALA) on growth, yield and some key physio-biochemical characteristics of two commercially
    important wheat cultivars (Shafaq-06 and Uqab-2000) under well watered [100% field capacity (FC)] and water-deficit
    (60 and 80% FC) conditions. Imposition of varying water regimes significantly decreased fresh and dry weights of shoots,
    photosynthetic pigments (a and b), non-photochemical quenching of chlorophyll fluorescence (NPQ), quenching coefficient
    for non-photochemical (N) of chlorophyll fluorescence (qN), K+ (potassium ion), Ca2+ (calcium ion) and P (phosphorus)
    accumulation in shoot and root and yield-related attributes. In contrast, water deficit regimes caused improvement in
    Fv/Fm (chlorophyll fluorescence measurement), coefficient of photochemical quenching (qP), proline, glycinebetaine
    (GB) and hydrogen peroxide (H2O2) contents. Foliar spray of ALA at the rate of 50, 100 and 150 mg/Lalong with control
    (no spray (NS) and/or water spray (WS)) significantly enhanced chlorophyll a and b pigments, qN, NPQ, qP, K+, Ca2+
    and P accumulation in both roots and shoots, proline, GB, total phenolics and malondialdehyde (MDA) contents and
    yield. The wheat Shafaq-06 was better in shoot dry weight, qN, NPQ and Fv/Fm, shoot and root K+, root Ca2+, proline,
    GB accumulation and yield attributes, while Uqab-2000 was better in chlorophyll a contents, root P and MDA contents.
    Overall, better growth and yield of Shafaq-06 than Uqab-2000 under water deficit regimes was found to be associated
    with ALA improved leaf fluorescence (qN, NPQ and Fv/Fm), shoot and root K+, root Ca2+, proline and GB accumulation.
  10. Development of a novel device for monitoring incentive spirometry performance
    Aqilah Leela T. Narayanan, Muhammad Akmal Ayob, Norayati Nordin, Arief Ruhullah A. Harris, Eko Supriyanto
    Sains Malaysiana, 2016;45:1121-1129.
    Lung atelectasis caused by shallow breathing patterns is common after cardiac, thoracic and upper abdominal surgeries.
    A common method used to address this problem is to encourage patients to perform breathing exercises using incentive
    spirometers in the postoperative period. However, to be effective, this procedure must be repeated regularly so that
    adequate lung volumes can be maintained to prevent atelectasis. Current models of single-use, low-cost incentive
    spirometers do not have features that can track and store data on breathing exercises. This makes it difficult to monitor
    patients’ breathing exercises effectively. We present here a device designed to be interfaced with the Spiro-ball incentive
    spirometer and programmed to monitor the incentive spirometry performance. Laboratory based validation performed
    indicate that there were no significant differences between the value obtained from the device and manual reading;
    p-value > 0.05 and root-mean-square error (RMSE) is 3.882. The device was able to retrieve and display pertinent data
    on incentive spirometry performance. It was also able to correctly track and register random sets of inspiration data
    through different dates and timelines. Being a separate entity which is reusable, it does not add to the cost of the singleuse
    incentive spirometer
  11. Environmental geological features of the red clay surrounding rock deformation under the influence of rock-fracture water
    Jiading Wang, Tianfeng Gu, Jianbin Wang, Yuanjun Xu, Peng Chen, Muhammad Aqeel Ashraf
    Sains Malaysiana, 2017;46:2049-2059.
    The development degree of fissure water in underground rock is a great trouble to the construction of railway tunnel, which will cause a series of environmental geological problems. Take the surrounding rock-section of the typical red clay in Lvliang-Mt. railway tunnel below the underground water level as an example, several aspects about the red clay surrounding rock will be researched, including pore water pressure, volume moisture content, stress of surrounding rock, vault subsidence and horizontal convergence through the field monitoring. Taking into account the importance of railway tunnel engineering, the large shear test of red clay was carried out at the construction site specially and the reliable situ shear strength parameters of surrounding rock will be obtained. These investigations and field tests helped to do a series of work: Three dimensional finite element numerical model of railway tunnel will be established, the deformation law of the red clay surrounding rock will be investigated, respectively, for the water-stress coupling effect and without considering it, the variation of the pore water pressure during excavation, the influence degree about the displacement field and stress field of water-stress coupling on red clay-rock will be discussed and the mechanism of the surrounding rock deformation will be submitted. Finally, the paper puts forward the feasible drainage scheme of the surrounding rock and the tunnel cathode. The geological environment safety of tunnel construction is effectively protected.
  12. Parameter optimisation for diimide reduction of liquid natural rubber in hydrazine hydrate/hydrogen peroxide system using response surface methodology (rsm)
    Muhammad Jefri Mohd Yusof, Nur Aidasyakirah Mohd Tahir, Fazira Firdaus, Siti Fairus M. Yusoff
    Sains Malaysiana, 2018;47:2055-2061.
    Getah asli cecair (LNR) dihasilkan daripada proses penyahpolimeran getah asli yang menghasilkan rantaian polimer
    lebih pendek dan berat molekular kurang daripada 105
    . Namun, LNR masih mempamerkan tahap degradasi dan ketahanan
    termal yang rendah seperti getah asli, disebabkan oleh kehadiran ikatan karbon ganda dua pada rantaian polimer.
    Dalam kajian ini, penurunan diimida menggunakan pengoksidaan hidrazin hidrat dengan hidrogen peroksida dijalankan
    untuk menghidrogenkan unit tidak tepu LNR. LNR terhidrogen (HLNR) dicirikan menggunakan spektrometer infra-merah
    (FTIR) dan spektrometer resonans magnetik nuklear (NMR). Pengoptimuman parameter tindak balas dilakukan dengan
    memanipulasi parameter masa dan suhu tindak balas berdasarkan kaedah rangsangan permukaan (RSM) dengan
    5-aras-2-faktor reka bentuk komposit putaran tengah (CCRD). Satu model kuadratik yang signifikan telah dihasilkan
    untuk menghubungkan dua parameter tersebut dengan nilai R2 adalah 0.9986, menunjukkan bahawa model yang terhasil
    adalah sangat sepadan dengan data uji kaji. Keputusan kajian menunjukkan bahawa peratus penghidrogenan boleh
    ditingkatkan sehingga 91.2%. Seterusnya, berdasarkan RSM, parameter yang optimum bagi penurunan diimida LNR ini
    didapati pada suhu 55.9o
    C selama 6.7 jam, menghasilkan 80.2% HLNR. Kajian ini telah menunjukkan reka bentuk uji kaji
    secara statistik yang novel bagi menghidrogenkan LNR. Pelbagai variasi peratus penghidrogenan produk HLNR dalam
    kajian ini menyumbang kepada lebih banyak aplikasi produk yang memerlukan peratusan ketepuan unit yang tertentu.
  13. Hydrogenation of liquid natural rubber using selenium-catalyzed system
    Nur Aidasyakirah Mohd Tahir, Mohamad Shahrul Fizree Idris, Muhammad Jefri Mohd Yusof, Siti Fairus M. Yusoff
    Sains Malaysiana, 2018;47:2073-2082.
    Kaedah rangsangan permukaan (RSM) dengan reka bentuk komposit putaran tengah (CCRD) telah digunakan untuk
    mengoptimumkan parameter bagi penghidrogenan getah asli cecair (LNR) dalam sistem hidrazin hidrat (HH) dan hidrogen
    peroksida (H2
    O2
    ) dengan kehadiran selenium sebagai mangkin. Parameter yang dikaji bagi tindak balas ini adalah
    nisbah mol HH:LNR (1.25-2.25), nisbah mol H2
    O2
    :LNR (1.25-2.25), suhu (40-80°C) dan masa tindak balas (4-8 jam).
    Berdasarkan data yang diperoleh, penghasilan getah asli cecair terhidrogen (HLNR) sesuai dijelaskan dengan model
    kuadratik. Model kuadratik ini mempunyai nilai pekali penentuan (R2
    ) sebanyak 0.9596 yang menunjukkan korelasi yang
    tinggi antara peratus penghidrogenan sebenar dengan peratus yang telah diramalkan. Berdasarkan plot permukaan
    tindak balas 3D, suhu tindak balas memainkan peranan penting dalam penghidrogenan LNR. Keadaan optimum yang
    diperoleh melalui RSM bagi kajian ini adalah nisbah mol HH:LNR pada 1.50, nisbah mol H2
    O2
    :LNR pada 2.00, suhu tindak
    balas pada 53.34°C dengan masa tindak balas selama 5.21 jam yang memberikan peratusan penghidrogenan HLNR
    sebanyak 68.98%. Persamaan polinomial kuadratik yang diperoleh daripada RSM ini berguna untuk menghasilkan HLNR
    dengan peratusan penghidrogenan yang dikehendaki.
  14. Structural and floristic pattern in a disturbed mangrove tropical swamp forest: a case study from the Langkawi UNESCO Global Geopark Forest, Peninsular Malaysia
    Wan Juliana Wan Ahmad, Wan Norilani Wan Ismail, Latiff A, Muhammad Razali Salam
    Sains Malaysiana, 2018;47:861-869.
    Forest structure, diversity and above-ground biomass assessment are important to understand the structural and floristic
    dynamics of a mangrove forest ecosystem. Our study provides valuable comparative analysis between two areas of
    disturbed mangroves at Kisap Forest Reserve, Langkawi Island. The two study sites were swamp forest at C5 which was
    disrupted by harvesting activities for charcoal production and C7 was disturbed by lightning strikes. A total of 1,217
    and 390 trees measuring 1 cm diameter and above were enumerated in 0.25 ha plots at both sites. Seven mangrove plant
    species in C5 and eight in C7 were recorded. Ceriops tagal and Rhizophora apiculata were the most prominent species
    in the C5 and C7, respectively, whereby the Rhizophoraceae was the densest family at both sites. The major contributor
    of total basal area at C5 and C7 were C. tagal (5.02 m2
    /ha) and R. apiculata (11.14 m2
    /ha). Similarly, C. tagal (22.41 t/
    ha) and R. apiculata (111.75 t/ha) also contributed the highest biomass in C5 and C7, respectively. Diversity and species
    richness were higher at C7 H’=1.22; R’=1.17 compared to C5 H’= 0.76; R’=0.85 and low evenness at both sites. High
    similarity was indicated between the two sites by 93%. The distribution of individuals in C7 was homogenous than that
    of C5, which had more saplings. In conclusion, anthropogenic activities resulted in lower productivity of forest compared
    to natural disturbances.
  15. Effects of gamma radiation treatment on three different medicinal plants: Microbial limit test, total phenolic content, in vitro cytotoxicity effect and antioxidant assay
    Khawory MH, Amat Sain A, Rosli MAA, Ishak MS, Noordin MI, Wahab HA
    Appl Radiat Isot, 2020 Mar;157:109013.
    PMID: 31889674 DOI: 10.1016/j.apradiso.2019.109013
    BACKGROUND AND AIM: The aim of this study is to evaluate the effects of gamma radiation treatment on three medicinal plants, namely Euodia malayana, Gnetum gnemon and Khaya senegalensis at two different forms; methanol leaf extracts and dried leaves respectively.

    EXPERIMENTAL PROCEDURE: The microbial limit test (MLT) studies indicated the suitable dosage of minimum and maximum gamma irradiation for leaf extracts as well as dried leaves of all the tested medicinal plants. Quantitative analysis of total phenolic content (TPC) analysis is based on calorimetric measurements determined using the Folin-Ciocalteu reagent with gallic acid (GA) used as the reference. In vitro cytotoxicity assay by using fibroblast (L929) cell lines was performed on each plant to determine the toxicity effect which sodium dodecyl sulfate (SDS) as the positive control. DPPH (2,2-diphenyl-1-picryl-hydrazyl) assay was conducted by using vitamin C and GA as the positive controls to determine the antioxidant property of each plant.

    RESULTS AND CONCLUSION: The MLT analysis indicated that the suitable dosage gamma irradiation for leaf extracts was 6-12 kGy and dried leaves were 9-13 kGy. The amount of GA concentration in each plant increased significantly from 30-51 mg GAE g-1 before treatment to 57-103 mg GAE g-1 after treatment with gamma radiation. This showed no significant effect of in vitro cytotoxicity activity before and after treatment with gamma irradiation in this study. Effective concentration (EC50) values of Khaya senegalensis plant reduced significantly (P ≤ 0.005) from 44.510 μg/ml before treatment to 24.691 μg/ml after treatment with gamma radiation, which indicate an increase of free radical scavenging activity.

  16. Fulltext The physical and morphological properties of kenaf fibres/ epoxy in coating treatment process
    Muhammad Mustakim Mohd Ghaztar, Nik Noor Idayu Nik Ibrahim, Sarani Zakaria, Ahmad Zafir Romli
    Scientific Research Journal, 2019;16(2):43-58.
    MyJurnal
    Natural fibre is known useful in many applications however, the existing fibre treatment method able to reduce its overall properties. In this study, a new, simple and cost-effective fibre coating treatment method was developed which was able to improve the physical and morphological properties that open a new path for natural based materials to be used in a more robust application. The physical and morphological properties of various coated kenaf fibres were analysed to comprehend the cutting behaviour of coated fibres after subjected to the pulverisation process. The kenaf fibres were individually immersed in 1:4, 1:5 and 1:6 epoxy to acetone coating solutions prior cured, and pulverised consecutively using 5 mm, 1 mm, 0.5 mm and 0.25 mm mesh sizes aperture. The morphological characteristic was analysed using polarised optical and scanning electron microscope. The result showed that 1:6 coating ratio solution able to effectively coat the fibres’ aspect ratio that forming individual coated fibre which in long length pulverised fibres. Moreover, the low viscous 1:6 solution able to penetrate inside fibre structure that supported by density and fibre crosssection analysis compare to the other solutions. In future, this analysis is crucial to give insight on the coated fibres behaviour after subjected to the mechanical means of cutting process that later relates to the reinforcing mechanism in the composite samples.
  17. Fulltext Factors associated with mortality of oral squamous cell carcinoma (OSCC) patients managed at Hospital USM
    Muhammad Azeem Yaaqoba, Suhaily Mohd Hairon, Thirumulu Ponnuraj Kannana,, Nurhayu Ab Rahmand
    Archives of Orofacial Sciences, 2019;14(1):1-63.
    MyJurnal
    This study was to determine the sociodemographic and clinicopathological factors that were associated with mortality of OSCC patients managed at Hospital USM. The prevalence of high-risk human papillomavirus (HPV) in these patients and its association with epithelial proliferation rate were also determined. A retrospective study was conducted whereby medical records of patients diagnosed with OSCC and tissue specimens from 2005 to 2015 were studied. Formalin-fixed paraffin-embedded (FFPE) tissue specimens were evaluated for histological grading of OSCC, p16 overexpression and Ki-67 immunostaining. Descriptive statistics, simple and multiple logistics regressions were used for data analysis. Prognostic factors for mortality includes male gender (AOR=10.89; 95% CI: 1.99, 59.65; p = 0.006), alcohol consumption (AOR = 16.45; 95% CI: 1.36, 59.65; p = 0.028), not receiving treatment (AOR = 5.88; 95% CI: 1.03, 33.61; p = 0.046) and late stage (T3, T4) at presentation (AOR = 4.85; 95% CI: 1.12, 21.02; p = 0.035). Significant association was found between high-risk HPV positivity and higher epithelial proliferation rate expression (p < 0.003) in the OSCC tissue specimens.
  18. Towards fast and cost-effective up-scaling of Nano-encapsulations by Ionic-gelation method using model drug for the treatment of atopic dermatitis
    Siddique MI, Tufail S, Ker ZH, Khan TM, Rasool F, Sohail MF, et al.
    Pak J Pharm Sci, 2019 Sep;32(5(Supplementary)):2299-2304.
    PMID: 31894058
    Chitosan nanoparticles (CSNPs) have proven their excellent drug delivery potential through various routes of administration and therefore, the need for large scale production of CSNPs for the commercialization is paramount. Their particle size and surface charge, drug loading capacity, and morphology were characterized in this study. Finally, drug release studies of both continuous and scalable modes were undertaken to ascertain suitability of CSNPs as a carrier for HC. The particle size of the large and small scale of HC-CSNPs was 253.3±16.4 nm and 225.4 ±9.6 nm, respectively. Besides, the surface charge of the large and small scale of HC-CSNPs was +35.3±0.3 mV and +32.6±2.5 mV, respectively. The size and surface charge of both HC-CSNPs were not proven to be statistically different. Drug loading capacity of large and small scale production of HC-CSNPs was high with 89%, and 83% of HC was loaded into CSNPs, respectively. Moreover, the morphology of both large and small scale production of HC-CSNPs had a similar shape and particle size. The drug release profile of CSNPs prepared by both methods showed a significantly (p<0.05) higher percentage release as compared to the free form. It is expected that positively charged nano-sized HC-CSNPs with high drug loading capacity could enhance the efficiency of drug delivery system to carry and diffuse into the target cells. The results obtained also suggested that the modified method applied could be further developed for large scale production of HC-CSNPs.
  19. Fulltext Isoniazid Conjugated Magnetic Nanoparticles Loaded with Amphotericin B as a Potent Antiamoebic Agent against Acanthamoeba castellanii
    Iqbal K, Abdalla SAO, Anwar A, Iqbal KM, Shah MR, Anwar A, et al.
    Antibiotics (Basel), 2020 May 25;9(5).
    PMID: 32466210 DOI: 10.3390/antibiotics9050276
    The pathogenic free-living amoeba, Acanthamoeba castellanii, is responsible for a rare but deadly central nervous system infection, granulomatous amoebic encephalitis and a blinding eye disease called Acanthamoeba keratitis. Currently, a combination of biguanides, amidine, azoles and antibiotics are used to manage these infections; however, the host cell cytotoxicity of these drugs remains a challenge. Furthermore, Acanthamoeba species are capable of transforming to the cyst form to resist chemotherapy. Herein, we have developed a nano drug delivery system based on iron oxide nanoparticles conjugated with isoniazid, which were further loaded with amphotericin B (ISO-NPs-AMP) to cause potent antiamoebic effects against Acanthamoeba castellanii. The IC50 of isoniazid conjugated with magnetic nanoparticles and loaded with amphotericin B was found to be 45 μg/mL against Acanthamoeba castellanii trophozoites and 50 μg/mL against cysts. The results obtained in this study have promising implications in drug discovery as these nanomaterials exhibited high trophicidal and cysticidal effects, as well as limited cytotoxicity against rat and human cells.
  20. Antiamoebic activity of 3-aryl-6,7-dimethoxyquinazolin-4(3H)-one library against Acanthamoeba castellanii
    Shahbaz MS, Anwar A, Saad SM, Kanwal, Anwar A, Khan KM, et al.
    Parasitol Res, 2020 Jul;119(7):2327-2335.
    PMID: 32476058 DOI: 10.1007/s00436-020-06710-7
    Acanthamoeba castellanii is a free-living amoeba which can cause a blinding keratitis and fatal granulomatous amoebic encephalitis. The treatment of Acanthamoeba infections is challenging due to formation of cyst. Quinazolinones are medicinally important scaffold against parasitic diseases. A library of nineteen new 3-aryl-6,7-dimethoxyquinazolin-4(3H)-one derivatives was synthesized to evaluate their antiamoebic activity against Acanthamoeba castellanii. One-pot synthesis of 3-aryl-6,7-dimethoxyquinazolin-4(3H)-ones (1-19) was achieved by reaction of 2-amino-4,5-dimethoxybenzoic acid, trimethoxymethane, and different substituted anilines. These compounds were purified and characterized by standard chromatographic and spectroscopic techniques. Antiacanthamoebic activity of these compounds was determined by amoebicidal, encystation, excystation and host cell cytopathogenicity in vitro assays at concentrations of 50 and 100 μg/mL. The IC50 was found to be between 100 and 50 μg/mL for all the compounds except compound 5 which did not exhibit amoebicidal effects at these concentrations. Furthermore, lactate dehydrogenase assay was also performed to evaluate the in vitro cytotoxicity of these compounds against human keratinocyte (HaCaT) cells. The results revealed that eighteen out of nineteen derivatives of quinazolinones significantly decreased the viability of A. castellanii. Furthermore, eighteen out of nineteen tested compounds inhibited the encystation and excystation, as well as significantly reduced the A. castellanii-mediated cytopathogenicity against human cells. Interestingly, while tested against human normal cell line HaCaT keratinocytes, all compounds did not exhibit any overt cytotoxicity. Furthermore, a detailed structure-activity relationship is also studied to optimize the most potent hit from these synthetic compounds. This report presents several potential lead compounds belonging to 3-aryl-6,7-dimethoxyquinazolin-4(3H)-one derivatives for drug discovery against infections caused by Acanthamoeba castellanii.
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