Displaying publications 1 - 20 of 40 in total

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  1. Zahra Dashtizadeh, Abdan, K., Jawaid, M., Mohd Asim Khan, Mohammad Behmanesh, Masoud Dashtizadeh, et al.
    MyJurnal
    Environmental issues have motivated researchers to replace synthetic fibres with natural fibres in the
    fabrication of polymer composites. However, natural fibres demonstrate weak mechanical or thermal
    properties which limit their different applications. Researchers have suggested fabrication of hybrid
    composites in order to improve the mechanical and thermal properties of natural fibre-based composites.
    Hybrid composites are made up by two or more fibres in one matrix or two polymer blends and with
    one natural fibre reinforcement. By hybridising one
    natural fibre with another natural fibre/synthetic
    fibre in one matrix, the resulting composite is a
    unique product (hybrid composites) that displays
    better mechanical and thermal properties in
    comparison with individual fibre-reinforced
    polymer composites. The advantages of developing
    hybrid composites are that they are more reliable
    for different applications and more environmental
    friendly. In this review paper, we present some
    recently published works related to mechanical
    and thermal properties of natural/natural fibres, and
    natural/synthetic fibre-based hybrid composites. Hybrid composites are one of the emerging fields in material science which has attracted attention for
    their different engineering applications.
  2. Maraina CH, Kamaliah MD, Ishak M
    Asian Pac J Allergy Immunol, 2004 Mar;22(1):33-7.
    PMID: 15366656
    A cross sectional study was conducted to determine the auto-antibody profile of Malay SLE patients in Kelantan, North East Malaysia and to correlate them with clinical presentations. Eighty-two Malay SLE patients who fulfilled the ARA criteria underwent the following tests: ANA, anti-dsDNA antibody, anti-ENA antibody and RF. The results revealed that ANA was positive in 91.5% of the patients, anti-dsDNA antibody in 53.7%, however, anti-ENA antibodies were positive in only 9.8% of the cases at the time of the study and none had a positive RF. The profile of autoantibodies was similar to other studies except for a lower incidence of anti-ENA antibodies. Sixty three percent of patients had lupus nephritis. The pattern of clinical presentations were noted to be more similar to those found among Chinese and Indian SLE populations than compared to the Caucasians. There was a significant association between anti-dsDNA antibody and lupus nephritis and between anti-ENA antibody and thrombocytopenia.
  3. Che Maraina CH, Kamaliah MD, Ishak M
    Asian Pac J Allergy Immunol, 2002 Dec;20(4):279-82.
    PMID: 12744629
    Anti-nuclear antibody (ANA) negative systemic lupus erythematosus (SLE) occurs in about 4-13% of SLE cases. A small group of ANA negative SLE patients with positive anti-Ro antibodies usually present with typical vasculitic skin lesions which can be associated with photosensitivity, renal disease, congenital heart block or neonatal lupus. We present a case of a persistently ANA negative patient who presented with joint pain, rashes, mouth ulcer and alopecia. Clinical diagnosis of systemic lupus erythematosus was made even though ANA was negative. She was started on steroids and went into remission. Later, she developed several episodes of convulsions associated with fever and prominent vasculitic lesions. The patient was also found to have microscopic hematuria, proteinuria, anemia and thrombocytopenia. Renal biopsy showed lupus nephritis class 1B. Due to the prominent skin lesions, we performed anti-extractable nuclear antigens (ENA) antibodies test and anti-Ro turned out to be positive. The final diagnosis was ANA negative SLE (Ro lupus) with cutaneous, renal, musculoskeletal, hematological and cerebral Involvement.
  4. Mutafi A, Yidris N, Ishak MR, Zahari R
    Heliyon, 2018 Nov;4(11):e00937.
    PMID: 30839801 DOI: 10.1016/j.heliyon.2018.e00937
    Steel sections are normally shaped via cold work manufacturing processes. The extent of cold work to shape the steel sections might induce residual stresses in the region of bending. Previously, researchers had performed studies on the influences of local buckling on the failure behavior of steel compression members which shown that failure will happen when most of the yielding has extended to the middle surface in the bend region of the sections. Therefore, these cold work methods may have major effect on the behavior of the steel section and also its load-bearing capability. In addition, another factor may play significant role in formed section's load-bearing capacity which is the longitudinal residual strain. The longitudinal residual strain raised during forming procedure can be used to define the section imperfection of the formed section and its relation to the existence of defects. Therefore, the main motivation of this research paper is to perform three-dimensional finite element (3D-FE) to investigate peak longitudinal residual strains of a thin-walled steel plate with large bending angle along member length. A 3D finite element simulation in ABAQUS has been employed to simulate this forming process. The study concluded that the longitudinal residual strain at the section corner edge was higher than those at the rest of the corner region. These strains at the edge were higher than the yield strain


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    of the formed section which occurred due to the lack of transverse restraint. This made the plate edge tended to bend toward the normal direction when it was under a high transverse bending. This causes a significant difference in longitudinal strain at the plate edge.
  5. Ilyas RA, Sapuan SM, Ishak MR
    Carbohydr Polym, 2018 Feb 01;181:1038-1051.
    PMID: 29253930 DOI: 10.1016/j.carbpol.2017.11.045
    Cellulose was extracted from sugar palm fibres (Arenga pinnata) by conducting delignification and mercerization treatments. Subsequently, sugar palm nanocrystalline celluloses (SPNCCs) were isolated from the extracted cellulose with 60wt% concentrated sulphuric acid. The chemical composition of sugar palm fibres were determined at different stages of treatment. Structural analysis was carried out by Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). Morphological analysis of extracted cellulose and isolated nanocrystalline cellulose (NCCs) was investigated by using field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), and transmission electron microscopy (TEM). The thermal stability of sugar palm fibres at different stages of treatment was investigated by thermogravimetric analysis (TGA). The results showed that lignin and hemicellulose were removed from the extracted cellulose through the delignification and mercerization process, respectively. The isolated SPNCCs were found to have length and diameters of 130±30nm and 9±1.96nm, respectively.
  6. Mallak SK, Bakri Ishak M, Mohamed AF
    PMID: 27624195 DOI: 10.1080/10962247.2016.1221366
    Malaysia is facing an increasing trend in industrial solid waste generation due to industrial development.Thus there is a paramount need in taking a serious action to move toward sustainable industrial waste management. The main aim of this study is to assess practicing solid waste minimization by manufacturing firms in Shah Alam industrial state, Malaysia. This paper presents a series of descriptive and inferential statistical analysis regarding the level and effects of practicing waste minimization methods, and seriousness of barriers preventing industries from practicing waste minimization methods. For this purpose the survey questions were designed such that both quantitative (questionnaire) and qualitative (semi-structures interview) data were collected concurrently. Analysis showed that, the majority of firms (92%) dispose their wastes rather than practice other sustainable waste management options. Also waste minimization methods such as segregation of wastes, on-site recycle and reuse, improve housekeeping and equipment modification were found to have significant contribution in waste reduction (p<0.05). Lack of expertise (M=3.50), lack of enough information (M= 3.54), lack of equipment modification (M= 3.16) and lack of specific waste minimization guidelines (M=3.49) have higher mean scores comparing with other barriers in different categories. These data were interpreted for elaborating of SWOT and TOWS matrix to highlight strengths, weaknesses, threats and opportunities. Accordingly, ten policies were recommended for improvement of practicing waste minimization by manufacturing firms as the main aim of this research. Implications This manuscript critically analysis waste minimization practices by manufacturing firms in Malaysia. Both qualitative and quantitative data collection and analysis were conducted to formulate SWOT and TOWS matrix in order to recommend policies and strategies for improvement of solid waste minimization by manufacturing industries. The results contribute to the knowledge and the findings of this study provide a useful baseline information and data on industrial solid waste generation and waste minimization practice.
  7. Ishak MI, Abdul Kadir MR, Sulaiman E, Abu Kasim NH
    Int J Oral Maxillofac Surg, 2012 Sep;41(9):1077-89.
    PMID: 22575179 DOI: 10.1016/j.ijom.2012.04.010
    The aim of this study was to compare two different types of surgical approaches, intrasinus and extramaxillary, for the placement of zygomatic implants to treat atrophic maxillae. A computational finite element simulation was used to analyze the strength of implant anchorage for both approaches in various occlusal loading locations. Three-dimensional models of the craniofacial structures surrounding a region of interest, soft tissue and framework were developed using computed tomography image datasets. The implants were modelled using computer-aided design software. The bone was assumed to be linear isotropic with a stiffness of 13.4 GPa, and the implants were assumed to be made of titanium with a stiffness of 110 GPa. Masseter forces of 300 N were applied at the zygomatic arch, and occlusal loads of 150 N were applied vertically onto the framework surface at different locations. The intrasinus approach demonstrated more satisfactory results and could be a viable treatment option. The extramaxillary approach could also be recommended as a reasonable treatment option, provided some improvements are made to address the cantilever effects seen with that approach.
  8. Sanyang ML, Sapuan SM, Jawaid M, Ishak MR, Sahari J
    Carbohydr Polym, 2016 08 01;146:36-45.
    PMID: 27112848 DOI: 10.1016/j.carbpol.2016.03.051
    The development and characterization of environmentally friendly bilayer films from sugar palm starch (SPS) and poly(lactic acid) (PLA) were conducted in this study. The SPS-PLA bilayer films and their individual components were characterized for their physical, mechanical, thermal and water barrier properties. Addition of 50% PLA layer onto 50% SPS layer (SPS50-PLA50) increased the tensile strength of neat SPS film from 7.74 to 13.65MPa but reduced their elongation at break from 46.66 to 15.53%. The incorporation of PLA layer significantly reduced the water vapor permeability as well as the water uptake and solubility of bilayer films which was attributed to the hydrophobic characteristic of the PLA layer. Furthermore, scanning electron microscopy (SEM) image of SPS50-PLA50 revealed lack of strong interfacial adhesion between the SPS and PLA. Overall, the incorporation of PLA layer onto SPS films enhances the suitability of SPS based films for food packaging.
  9. Jumaidin R, Sapuan SM, Jawaid M, Ishak MR, Sahari J
    Int J Biol Macromol, 2016 Aug;89:575-81.
    PMID: 27177458 DOI: 10.1016/j.ijbiomac.2016.05.028
    The aim of this work is to study the behavior of biodegradable sugar palm starch (SPS) based thermoplastic containing agar in the range of 10-40wt%. The thermoplastics were melt-mixed and then hot pressed at 140°C for 10min. SEM investigation showed good miscibility between SPS and agar. FT-IR analysis confirmed that SPS and agar were compatible and inter-molecular hydrogen bonds existed between them. Incorporation of agar increased the thermoplastic starch tensile properties (Young's modulus and tensile strength). The thermal stability and moisture uptake increased with increasing agar content. The present work shows that starch-based thermoplastics with 30wt% agar content have the highest tensile strength. Higher content of agar (40wt%) resulted to more rough cleavage fracture and slight decrease in the tensile strength. In conclusion, the addition of agar improved the thermal and tensile properties of thermoplastic SPS which widened the potential application of this eco-friendly material. The most promising applications for this eco-friendly material are short-life products such as packaging, container, tray, etc.
  10. Sanyang ML, Sapuan SM, Jawaid M, Ishak MR, Sahari J
    J Food Sci Technol, 2016 Jan;53(1):326-36.
    PMID: 26787952 DOI: 10.1007/s13197-015-2009-7
    In this study, sugar palm starch (SPS) films were developed using glycerol (G), sorbitol (S) or their combination (GS) as plasticizers at the ratio of 15, 30 and 45 (wt)% using casting technique. The addition of plasticizers to SPS film-forming solutions helped to overcome the brittle and fragile nature of unplasticized SPS films. Increased plasticizer concentration resulted to an increase in film thickness, moisture content and solubility. On the contrary, density and water absorption of plasticized films decreased with increasing plasticizer concentration. Raising the plasticizer content from 15 to 45 % showed less effect on the moisture content and water absorption of S-plasticized films. Films containing glycerol and glycerol-sorbitol plasticizer (G, and GS) demonstrated higher moisture content, solubility and water absorption capacity compared to S-plasticized films. The results obtained in this study showed that plasticizer type and concentration significantly improves film properties and enhances their suitability for food packaging applications.
  11. Houkin K, Fukuhara S, Selladurai BM, Zurin AA, Ishak M, Kuroda S, et al.
    Neurol. Med. Chir. (Tokyo), 1999 Oct;39(11):773-7; discussion 777-8.
    PMID: 10598447
    A new image transmission and teleconference system using international digital telephone services was established between Japan and Malaysia. This new system consists of an ordinary personal computer, image scanner, and terminal adapter for digital telephone lines. The quality of images transferred using this system was high enough for diagnosis and discussion except for images such as radiographs requiring huge data transfer. Transmission of one image took approximately 20 seconds. The cost performance was almost equal to the conventional mailing system. The most remarkable advantage of this new system is the high quality of transferred images, the cost and time performance, and security of the medical information. New communication systems using international digital networks including the internet may allow re-distribution of medical resources between advanced countries and developing countries in neurosurgery.
  12. Ilyas RA, Sapuan SM, Ishak MR, Zainudin ES
    Carbohydr Polym, 2018 Dec 15;202:186-202.
    PMID: 30286991 DOI: 10.1016/j.carbpol.2018.09.002
    Sugar palm fibre (SPF) was treated with NaClO2, bleached with NaOH and subsequently hydrolyzed with acid to obtain sugar palm nanocrystalline cellulose (SPNCCs). Bionanocomposites in the form of films were prepared by mixing sugar palm starch (SPS) and sorbitol/glycerol with different nanofiller SPNCCs compositions (0-1.0 wt%) using solution casting method. The resulting fibres and nanocomposites were characterized in terms of morphology (FESEM and TEM), footprint, crystallinity (XRD), light transmittance, biodegradability, physical, water barrier, thermal (TGA, DSC and DMA) and mechanical properties. The length (L), diameter (D) and L/D values of the SPNCCs were 130 ± 30.23, 8.5 ± 1.82 nm, and 15.3, respectively. The SPS/SPNCCs nanocomposite films exhibited higher crystallinity, tensile strength, Young's modulus, thermal and water-resistance compared to the neat SPS film. The results showed that the tensile strength and moduli of the bionanocomposites increased after being reinforced with SPNCCs and the optimum nanofiller content was 0.5%.
  13. Ilyas RA, Sapuan SM, Ishak MR, Zainudin ES
    Int J Biol Macromol, 2019 Feb 15;123:379-388.
    PMID: 30447353 DOI: 10.1016/j.ijbiomac.2018.11.124
    Nanofibrillated cellulose (NFCs) were extracted from sugar palm fibres (SPS) in two separate stages; delignification and mercerization to remove lignin and hemicellulose, respectively. Subsequently, the obtained cellulose fibres were then mechanically extracted into nanofibres using high pressurized homogenization (HPH). The diameter distribution sizes of the isolated nanofibres were dependent on the cycle number of HPH treatment. TEM micro-images displayed the decreasing trend of NFCs diameter, from 21.37 to 5.5 nm when the number of cycle HPH was increased from 5 to 15 cycles, meanwhile TGA and XRD analysis showed that the degradation temperature and crystallinity of the NFCs were slightly increased from 347 to 347.3 °C and 75.38 to 81.19% respectively, when the number of cycles increased. Others analysis also were carried on such as FT-IR, FESEM, AFM, physical properties, zeta potential and yield analysis. The isolated NFCs may be potentially applied in various application, such as tissue engineering scaffolds, bio-nanocomposites, filtration media, bio-packaging and etc.
  14. Ishak MH, Zhun OC, Shaari R, Rahman SA, Hasan MN, Alam MK
    Mymensingh Med J, 2014 Oct;23(4):781-6.
    PMID: 25481601
    This study evaluated the validity of panoramic radiography and cone beam computed tomography (CBCT) in the assessment of mandibular canal and impacted third molar. In this descriptive-analytical study, 58 mandibular third molars from 42 patients who showed a close relationship between impacted third molar and canal on panoramic radiographs were selected. They were then classified into seven radiographic markers in panoramic radiographs (superimposition, darkening of the root, interruption of the white lines, root narrowing, canal diversion, canal narrowing, and also closed distance in OPG <1mm). The groups of markers were further assessed with CBCT to see presence or absence of contact. The three most common markers seen in panoramic images are superimposition, interruption of white line and root darkening. In CBCT, superimposition marker always presented higher frequency of contact with canal compared to non-contact group. There are 31% of teeth presented with interruption of white lines and there are 29.3% of teeth presented with superimposition. About 55.6% and 35.3% of the impacted mandibular third molars which indicated interruption of white lines and superimposition also indicated contact in the CBCT respectively. Presence or absence of radiological sign in panoramic radiography was not properly predict a close relationship with third molar and it is suggested that in case of tooth-canal overlapping, the patient should be referred for CBCT assessment.
  15. Ishak MR, Sapuan SM, Leman Z, Rahman MZ, Anwar UM, Siregar JP
    Carbohydr Polym, 2013 Jan 16;91(2):699-710.
    PMID: 23121967 DOI: 10.1016/j.carbpol.2012.07.073
    Sugar palm (Arenga pinnata) is a multipurpose palm species from which a variety of foods and beverages, timber commodities, biofibres, biopolymers and biocomposites can be produced. Recently, it is being used as a source of renewable energy in the form of bio-ethanol via fermentation process of the sugar palm sap. Although numerous products can be produced from sugar palm, three products that are most prominent are palm sugar, fruits and fibres. This paper focuses mainly on the significance of fibres as they are highly durable, resistant to sea water and because they are available naturally in the form of woven fibre they are easy to process. Besides the recent advances in the research of sugar palm fibres and their composites, this paper also addresses the development of new biodegradable polymer derived from sugar palm starch, and presents reviews on fibre surface treatment, product development, and challenges and efforts on properties enhancement of sugar palm fibre composites.
  16. Ishak MF, Chua KH, Asma A, Saim L, Aminuddin BS, Ruszymah BH, et al.
    Int J Pediatr Otorhinolaryngol, 2011 Jun;75(6):835-40.
    PMID: 21543123 DOI: 10.1016/j.ijporl.2011.03.021
    This study was aimed to see the difference between chondrocytes from normal cartilage compared to chondrocytes from microtic cartilage. Specific attentions were to characterize the growth of chondrocytes in terms of cell morphology, growth profile and RT-PCR analysis.
  17. Ishak MF, Aminuddin BS, Asma A, Lokman BS, Ruszymah BH, Goh BS
    Med J Malaysia, 2008 Jul;63 Suppl A:117-8.
    PMID: 19025013
    Chondrocytes were isolated from normal and microtic human auricular cartilage after ear surgery carried out at Universiti Kebangsaan Malaysia Medical Centre. Chondrocytes were cultured and expanded until passage 4. After reached confluence, cultured chondrocytes at each passage (P1, P2, P3 and P4) were harvested and assigned for growth profile analysis. There was no significant difference in cell viability between both normal and microtic samples (p = 0.84). Both samples showed no significant differences for growth profile parameters in terms of growth rate, population doubling time and total number of cell doubling, except in passage 1, where there is significant difference in cell growth rate (p = 0.004). This preliminary data has indicated that chondrocytes from microtic cartilage has the potential to be used in the reconstruction of human pinna in the future.
  18. Chan KM, Rajab NF, Ishak MH, Ali AM, Yusoff K, Din LB, et al.
    Chem Biol Interact, 2006 Feb 1;159(2):129-40.
    PMID: 16297902
    Restenosis represents a major impediment to the success of coronary angioplasty. Abnormal proliferation of vascular smooth muscle cells (VSMCs) has been shown to be an important process in the pathogenesis of restenosis. A number of agents, particularly rapamycin and paclitaxel, have been shown to impact on this process. This study was carried out to determine the mechanisms of cytotoxicity of goniothalamin (GN) on VSMCs. Results from MTT cytotoxicity assay showed that the IC(50) for GN was 4.4 microg/ml (22 microM), which was lower compared to the clinically used rapamycin (IC(50) of 25 microg/ml [27.346 microM]). This was achieved primarily via apoptosis where up to 25.83 +/- 0.44% of apoptotic cells were detected after 72 h treatment with GN. In addition, GN demonstrated similar effects as rapamycin in inhibiting VSMCs proliferation using bromodeoxyuridine (BrdU) cell proliferation assay after 72 h treatment at IC(50) concentration (p > 0.05). In order to understand the mechanisms of GN, DNA damage detection using comet assay was determined at 2h post-treatment with GN. Our results showed that there was a concentration-dependent increase in DNA damage in VSMCs prior to cytotoxicity. Moreover, GN effects were comparable to rapamycin. In conclusion, our data show that GN initially induces DNA damage which subsequently leads to cytotoxicity primarily via apoptosis in VSMCs.
  19. Abubakar U, Zulkarnain AI, Samri F, Hisham SR, Alias A, Ishak M, et al.
    BMC Complement Med Ther, 2020 Sep 18;20(1):285.
    PMID: 32948163 DOI: 10.1186/s12906-020-03082-4
    BACKGROUND: Dysmenorrhea is a common problem that affects female students' quality of life and academic activities. Complementary and alternative therapies (CATs) are used for the treatment of dysmenorrhea. This study investigated the practices and perceptions of female undergraduate students with dysmenorrhea towards CATs.

    METHODS: This was a cross-sectional study conducted among undergraduate pharmacy students in a public university in Malaysia using a validated and pre-tested self-administered questionnaire. The study was conducted in November and December 2019. The data was analysed using descriptive and inferential statistical tests.

    RESULTS: Of the 318 female undergraduate students invited, 219 completed the questionnaire (response rate: 68.9%) with 52% aged between 21 and 23 years. The prevalence of dysmenorrhea was 72.1%, and the prevalence of ever-use and current use of CATs was 70.3 and 54.4%, respectively. Bed rest (71.5%), hot compress/heating pad (47.5%) and massage (43.0%) were the most common CATs used by the respondents. The most common reasons for using CAT were to reduce the need for analgesics (61.4%), efficacy (37.3%) and recommendation by others (32.9%). About 23 and 9% of the respondents believed that CATs were equally "effective" and "more effective" than analgesics, respectively. Reducing the need for analgesics (AOR: 4.066, 95% CI: 2.136-7.739) and those who agreed that CATs are effective (AOR: 2.701, 95% CI: 1.337-5.457) were independently associated with the current use CATs for the treatment of menstrual pain.

    CONCLUSION: The prevalence of ever-use and current use of CATs is high among female undergraduate pharmacy students. Bed rest and heat applications are the most common CATs used. Reducing the need for analgesics and efficacy are the factors associated with the current use of CATs. Students should be educated about the safe and effective use of CATs to reduce adverse effects and improve their quality of life.

  20. Hamid MF, Idroas MY, Ishak MZ, Zainal Alauddin ZA, Miskam MA, Abdullah MK
    Biomed Res Int, 2016;2016:1679734.
    PMID: 27419127 DOI: 10.1155/2016/1679734
    Torrefaction process of biomass material is essential in converting them into biofuel with improved calorific value and physical strength. However, the production of torrefied biomass is loose, powdery, and nonuniform. One method of upgrading this material to improve their handling and combustion properties is by densification into briquettes of higher density than the original bulk density of the material. The effects of critical parameters of briquetting process that includes the type of biomass material used for torrefaction and briquetting, densification temperature, and composition of binder for torrefied biomass are studied and characterized. Starch is used as a binder in the study. The results showed that the briquette of torrefied rubber seed kernel (RSK) is better than torrefied palm oil shell (POS) in both calorific value and compressive strength. The best quality of briquettes is yielded from torrefied RSK at the ambient temperature of briquetting process with the composition of 60% water and 5% binder. The maximum compressive load for the briquettes of torrefied RSK is 141 N and the calorific value is 16 MJ/kg. Based on the economic evaluation analysis, the return of investment (ROI) for the mass production of both RSK and POS briquettes is estimated in 2-year period and the annual profit after payback was approximately 107,428.6 USD.
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