Displaying publications 41 - 60 of 274 in total

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  1. Oskoueian E, Abdullah N, Ahmad S
    Molecules, 2012 Sep 10;17(9):10816-30.
    PMID: 22964499 DOI: 10.3390/molecules170910816
    Jatropha meal produced from the kernel of Jatropha curcas Linn. grown in Malaysia contains phorbol esters (PEs). The potential benefits of PEs present in the meal as anticancer agent are still not well understood. Hence, this study was conducted to evaluate the cytotoxic effects and mode of actions of PEs isolated from Jatropha meal against breast (MCF-7) and cervical (HeLa) cancer cell lines. Isolated PEs inhibited cells proliferation in a dose-dependent manner of both MCF-7 and HeLa cell lines with the IC₅₀ of 128.6 ± 2.51 and 133.0 ± 1.96 µg PMA equivalents/mL respectively, while the values for the phorbol 12-myristate 13-acetate (PMA) as positive control were 114.7 ± 1.73 and 119.6 ± 3.73 µg/mL, respectively. Microscopic examination showed significant morphological changes that resemble apoptosis in both cell lines when treated with PEs and PMA at IC₅₀ concentration after 24 h. Flow cytometry analysis and DNA fragmentation results confirmed the apoptosis induction of PEs and PMA in both cell lines. The PEs isolated from Jatropha meal activated the PKC-δ and down-regulated the proto-oncogenes (c-Myc, c-Fos and c-Jun). These changes probably led to the activation of Caspase-3 protein and apoptosis cell death occurred in MCF-7 and HeLa cell lines upon 24 h treatment with PEs and PMA. Phorbol esters of Jatropha meal were found to be promising as an alternative to replace the chemotherapeutic drugs for cancer therapy.
  2. Karimi E, Jaafar HZ, Ahmad S
    Molecules, 2011 May 27;16(6):4438-50.
    PMID: 21623314 DOI: 10.3390/molecules16064438
    A local herb, Kacip Fatimah, is famous amongst Malay women for its uses in parturition; however, its phytochemical contents have not been fully documented. Therefore, a study was performed to evaluate the phenolics, flavonoids, and total saponin contents, and antibacterial and antifungal properties of the leaf, stem and root of three varieties of Labisia pumila Benth. Total saponins were found to be higher in the leaves of all three varieties, compared to the roots and stems. Leaves of var. pumila exhibited significantly higher total saponin content than var. alata and lanceolata, with values of 56.4, 43.6 and 42.3 mg diosgenin equivalent/g dry weight, respectively. HPLC analyses of phenolics and flavonoids in all three varieties revealed the presence of gallic acid, caffeic acid, rutin, and myricetin in all plant parts. Higher levels of flavonoids (rutin, quercitin, kaempferol) were observed in var. pumila compared with alata and lanceolata, whereas higher accumulation of phenolics (gallic acid, pyrogallol) was recorded in var. alata, followed by pumila and lanceolata. Antibacterial activities of leaf, stem and root extracts of all varieties determined against both Gram positive (Micrococcus luteus, Bacillus subtilis B145, Bacillus cereus B43, Staphylococcus aureus S1431) and Gram negative (Enterobacter aerogenes, Klebsiella pneumonia K36, Escherichia coli E256, Pseudomonas aeruginosa PI96) pathogens showed that crude methanolic extracts are active against these bacteria at low concentrations, albeit with lower antibacterial activity compared to kanamycin used as the control. Antifungal activity of methanolic extracts of all plant parts against Fusarium sp., Candida sp. and Mucor using the agar diffusion disc exhibited moderate to appreciable antifungal activities compared to streptomycin used as positive control.
  3. Citalingam K, Zareen S, Shaari K, Ahmad S
    BMC Complement Altern Med, 2013 Aug 23;13:213.
    PMID: 23971790 DOI: 10.1186/1472-6882-13-213
    BACKGROUND: Hyaluronidases have been found as the target enzymes in the development of osteoarthritis (OA) disease. While there is still no curative treatment for this disease, recent studies on the treatment of OA were focused on the effectiveness of natural products which are expected to improve the symptoms with minimal side effects. The aim of this study was to screen selected Malaysian plants on their anti-hyaluronidase activity as well as to evaluate the active plant and its derived fractions on its potential anti-arthritic and antioxidant activities.

    METHODS: A total of 20 methanolic crude extracts (bark and leaf) from ten different plants were screened using a colorimetric hyaluronidase enzymatic assay. The active plant extract (Payena dasyphylla) was then studied for its hyaluronidase inhibitory activity in the interleukin-1β (IL-1β) stimulated human chondrocytes cell line (NHAC-kn) using zymography method. The Payena dasyphylla methanolic bark extract was then fractionated into several fractions in where the ethyl acetate (EA) fraction was evaluated for its inhibitory effects on the HYAL1 and HYAL2 gene expressions using reverse transcription-polymerase chain reaction (RT-PCR) technique. While the MMP-3 and MMP-13 protein expressions were evaluated using western blot method. The phenolic and flavonoid contents of the three fractions as well as the antioxidant property of the EA fraction were also evaluated.

    RESULTS: Bark extract of Payena dasyphylla (100 μg/ml) showed the highest inhibitory activity against bovine testicular hyaluronidase with 91.63%. The plant extract also inhibited hyaluronidase expression in the cultured human chondrocyte cells in response to IL-1β (100 ng/ml). Similarly, treatment with Payena dasyphylla ethyl acetate (EA) fraction (100 μg/ml) inhibited the HYAL1 and HYAL2 mRNA gene expressions as well as MMP-3 and MMP-13 protein expression in a dose dependent manner. Payena dasyphylla EA fraction has demonstrated the highest amount of phenolic and flavonoid content with 168.62 ± 10.93 mg GAE/g and 95.96 ± 2.96 mg RE/g respectively as compared to water and hexane fractions. In addition, the Payena dasyphylla EA fraction showed strong antioxidant activity with IC₅₀ value of 11.64 ± 1.69 μg/mL.

    CONCLUSION: These findings have shown that Payena dasyphylla might contained potential phenolic compounds that inhibiting the key enzyme in osteoarthritis development, which is the hyaluronidase enzyme through interruption of HYAL1 and HYAL1 gene expressions. The degradation of cartilage could also be inhibited by the plant through suppression of MMP-3 and MMP-13 protein expressions. We also reported that the inhibitory effect of Payena dasyphylla on hyaluronidase activity and expression might be due to its anti-oxidant property.

  4. Lee JJ, Ahmad S, Roslan HA
    Pak J Biol Sci, 2013 Dec 15;16(24):1913-21.
    PMID: 24517006
    Morinda citrifolia, is a valuable medicinal plant with a wide range of therapeutic properties and extensive transformation study on this plant has yet been known. Present study was conducted to establish a simple and reliable transformation protocol for M. citrifolia utilising Agrobacterium tumefaciens via direct seed exposure. In this study, the seeds were processed by tips clipping and dried and subsequently incubated in inoculation medium. Four different parameters during the incubation such as incubation period, bacterial density, temperature and binary vectors harbouring beta-glucuronidase (GUS) gene (pBI121 and pGSA1131), were tested to examine its effect on transformation efficiency. The leaves from the treated and germinated seedlings were analysed via Polymerase Chain Reaction (PCR), histochemical assay of the GUS gene and reverse transcription-PCR (RT-PCR). Results of the study showed that Agrobacterium strain LBA4404 with optical density of 1.0 and 2 h incubation period were optimum for M. citrifolia transformation. It was found that various co-cultivation temperatures tested and type of vector used did not affect the transformation efficiency. The highest transformation efficiency for M. citrifolia direct seed transformation harbouring pBI121 and pGSA1131 was determined to be 96.8% with 2 h co-cultivation treatment and 80.4% when using bacterial density of 1.0, respectively. The transformation method can be applied for future characterization study of M. citrifolia.
  5. Shadid KA, Shaari K, Abas F, Israf DA, Hamzah AS, Syakroni N, et al.
    Phytochemistry, 2007 Oct;68(20):2537-44.
    PMID: 17602714
    Phytochemical studies on the leaves and trunk bark of Garcinia cantleyana yielded five caged-xanthonoids including one tetra- and four tri-prenylated xanthones, cantleyanone A (1), 7-hydroxyforbesione (2) and cantleyanones B-D (4-6), as well as a simple xanthone, 4-(1,1-dimethylprop-2-enyl)-1,3,5,8-tetrahydroxyxanthone (3). Eight other known compounds, deoxygaudichaudione A, gaudichaudione H, friedelin, garbogiol, macranthol, glutin-5-en-3beta-ol, and a mixture of sitosterol and stigmasterol were also isolated. Their structures were elucidated by means of spectroscopic data and comparison of their NMR data with literature values. Significant cytotoxicity against MDA-MB-231, CaOV-3, MCF-7 and HeLa cancer cell-lines was demonstrated by cantleyanones B-D, 7-hydroxyforbesione, deoxygaudichaudione A and macranthol, with IC(50) values ranging from 0.22 to 17.17 microg/ml.
  6. Halim AS, Nor FM, Mat Saad AZ, Mohd Nasir NA, Norsa'adah B, Ujang Z
    J Taibah Univ Med Sci, 2018 Dec;13(6):512-520.
    PMID: 31435371 DOI: 10.1016/j.jtumed.2018.10.004
    Objectives: Chitosan, the N-deacetylated derivative of chitin, has useful biological properties that promote haemostasis, analgesia, wound healing, and scar reduction; chitosan is bacteriostatic, biocompatible, and biodegradable. This study determined the efficacy of chitosan derivative film as a superficial wound dressing.

    Methods: This multicentre randomised controlled trial included 244 patients, of whom 86 were treated with chitosan derivative film and 84 with hydrocolloid. The percentage of epithelisation, as well as patient comfort, clinical signs, and patient convenience in application and removal of the dressings were assessed.

    Results: The primary outcome of this study was the percentage of epithelisation. Except for race (p = 0.04), there were no significant differences between groups in sex, age, antibiotic usage, or initial wound size (p > 0.05). There was no significant difference in the mean epithelisation percentage between groups (p = 0.29). Patients using chitosan derivative film experienced more pain during removal of dressing than those in the hydrocolloid group (p = 0.007). The chitosan derivative film group showed less exudate (p = 0.036) and less odour (p = 0.024) than the control group. Furthermore, there were no significant differences between groups in terms of adherence, ease of removal, wound drainage, erythema, itchiness, pain, and tenderness. No oedema or localised warmth was observed during the study.

    Conclusion: This study concluded that chitosan derivative film is equivalent to hydrocolloid dressing and can be an option in the management of superficial and abrasion wounds.

    Clinical trial No: NMRR-11-948-10565.

  7. Venkatason P, Zubairi YZ, Hafidz I, Wan WA, Zuhdi AS
    Ann Saudi Med, 2016 5 30;36(3):184-9.
    PMID: 27236389 DOI: 10.5144/0256-4947.2016.184
    BACKGROUND: The administration of evidence-based pharmacotherapy and timely primary percutaneous coronary intervention have been shown to improve outcome in ST elevation myocardial infarction (STEMI). However, implementation remains a challenge due to the limitations in facilities, expertise and funding.

    OBJECTIVES: To investigate adherence to guideline-based management and mortality of STEMI patients in Malaysia.

    DESIGN: Retrospective analysis.

    SETTINGS: STEMI patients from 18 participating hospital across Malaysia included in the National Cardiovascular Database-Acute Coronary Syndrome (NCVD-ACS) registry year 2006 to 2013.

    PATIENTS AND METHODS: Patients were categorized into four subgroups based on the year of admission (2006 to 2007, 2008 to 2009, 2010 to 2011 and 2012 to 2013). Baseline characteristics and clinical presentation, in-hospital pharmacotherapy, invasive revascularization and in-hospital/30-day mortality were analysed and compared between the subgroups.

    MAIN OUTCOME MEASURE(S): Rate of in-hospital catheterization/percutaneous coronary intervention.

    RESULTS: The registry contained data on 19483 patients. Intravenous thrombolysis was the main reperfusion therapy. Although the overall rate of in-hospital catheterisation/PCI more than doubled over the study period, while the use of primary PCI only slowly increased from 7.6% in 2006/2007 to 13.6% in 2012/2013. The use of evidence-based oral therapies increased steadily over the years except for ACe-inhibitors and angiotensin-receptor blockers. The adjusted risk ratios (RR) for in-hospital mortality for the four sub-groups have not shown any significant improvement. The 30-day adjusted risk ratios however showed a significant albeit gradual risk reduction (RR 0.773 95% CI 0.679-0.881, P < .001).

    CONCLUSION: Adherence to evidence-based treatment in STEMI in Malaysia is still poor especially in terms of the rate of primary PCI. Although there is a general trend toward reduced 30-day mortality, the reduction was only slight over the study period. Drastic effort is needed to improve adherence and clinical outcomes.

    LIMITATION: Retrospective registry data with inter-hospital variation.

  8. Rosli MA, Mohd Nasir NA, Mustafa MZ, Othman MA, Zakaria Z, Halim AS
    J Taibah Univ Med Sci, 2024 Feb;19(1):209-219.
    PMID: 38124990 DOI: 10.1016/j.jtumed.2023.11.003
    PURPOSE: Kelulut honey contains trehalulose and has high antioxidant content, such as phenolic and flavonoid substances, which can promote wound healing. This study evaluated the effectiveness of Kelulut honey in diabetic wound healing compared to a commercially available conventional gel dressing (Intrasite gel).

    METHODS: A prospective, randomized, single-blinded control trial was performed on eligible diabetic patients with full-thickness cavity wounds. Patients' demographics, size and site of wounds, and baseline routine blood investigations were recorded. The wounds were dressed every other day with Kelulut honey for the intervention group or gel for the control group. The wound size reduction and granulation tissue formation percentage were calculated every 6 days for 1 month.

    RESULTS: Seventy-one patients were randomized. After 30 days of follow-up, 62 participants were available for analysis: 30 from the control group and 32 from the treatment group. The control group had increased granulation tissue at baseline and more wounds on the lower limb and posterior trunk. Both groups showed an increasing mean and median percentage of wound epithelialization and granulation tissue over time, with significantly higher values at every timepoint in the honey group (p 

  9. Ahmad S, Mahidon R, Shukur MH, Hamdan A, Kasmin M
    J Orthop Surg (Hong Kong), 2014 Dec;22(3):325-8.
    PMID: 25550011
    To evaluate the outcome of reconstruction for chronic grade-II posterior cruciate ligament (PCL) deficiency in Malaysian military personnel.
  10. Razali S, Kirkman M, Ahmad SH, Fisher J
    Child Abuse Negl, 2014 Oct;38(10):1715-24.
    PMID: 25048164 DOI: 10.1016/j.chiabu.2014.06.008
    Infant abandonment and infanticide are poorly understood in Malaysia. The information available in the public arena comes predominantly from anecdotal sources. The aim of this study was to describe the prevalence and characteristics of infanticide and illegal infant abandonment in Malaysia and to estimate annual rates for the most recent decade. Summaries of data about infanticide and illegal infant abandonment were gathered from police records; the annual number of live births was ascertained from the national registry. The estimated inferred infanticide rates for Malaysia were compared with the infanticide rates among countries of very high, high, medium, and low rankings on the Human Development, Gender Inequality, and Gini indices. From 1999 to 2011, 1,069 cases of illegal infant abandonment were recorded and 1,147 people were arrested as suspected perpetrators. The estimated inferred infanticide rate fluctuated between 4.82 and 9.11 per 100,000 live births, a moderate rate relative to the infanticide rates of other countries. There are substantial missing data, with details undocumented for about 78-87% of cases and suspected perpetrators. Of the documented cases, it appeared that more boys than girls were victims and that suspected perpetrators were predominantly Malays who were women, usually mothers of the victim; the possibility of arrest bias must be acknowledged. Economic and social inequality, particularly gender inequality, might contribute to the phenomena of infanticide and abandonment. Strategies to reduce rates of infanticide and illegal infant abandonment in Malaysia will require strengthening of the surveillance system and attention to the gender-based inequalities that underpin human development.
  11. Zakaria ZA, Balan T, Suppaiah V, Ahmad S, Jamaludin F
    J Ethnopharmacol, 2014 Feb 12;151(3):1184-1193.
    PMID: 24380736 DOI: 10.1016/j.jep.2013.12.045
    ETHNOPHARMACOLOGICAL RELEVANCE: Muntingia calabura L. (Muntingiaceae) is locally known as kerukup siam. Its leaves, flowers, barks and roots have been used traditionally in East Asia and South America to treat various diseases including ulcer-related diseases. The present study aimed to investigate the mechanism(s) of gastroprotective effect of methanol extract of Muntingia calabura leaves (MEMC) using the pylorus ligation induced gastric ulceration in rats.

    MATERIALS AND METHODS: Five groups of rats (n=6) were administered orally once daily for 7 days with 8% Tween 80 (negative control), 100 mg/kg ranitidine (positive control), or MEMC (100, 250 or 500 mg/kg), followed by the ulcer induction via ligation of the pyloric part of the rat's stomach. This was followed by the macroscopic analysis of the stomach, evaluation of gastric content parameters, and quantification of mucus content. The antioxidant (measured using the superoxide anion and 2,2-diphenyl-1-picrylhydrazyl (DPPH)-radical scavenging, oxygen radical absorbance capacity (ORAC) and total phenolic content (TPC) assays), anti-inflammatory (evaluated using the in vitro lipoxygenase and xanthine oxidase assays), phytoconstituents and HPLC analysis of MEMC were also carried out.

    RESULTS: The MEMC significantly (p<0.05) reduced gastric lesion in this model. Furthermore, the extract also significantly (p<0.01) reduced the volume of gastric content whereas the total acidity was significantly (p<0.05) reduced in the doses of 100 and 500 mg/kg MEMC. Moreover, the mucus content increased significantly (p<0.01) in MEMC-treated rats. The extract also showed high antioxidant and anti-inflammatory activities in all assays tested, and demonstrated the presence of high tannins and saponins followed by flavonoids.

    CONCLUSION: The MEMC exerted gastroprotective effect via several mechanisms including the anti-secretory, antioxidant and anti-inflammatory activities. These activities could be attributed to the presence of tannins, saponins and flavonoids (e.g. rutin, quercitrin, fisetin and dihydroquercetin).

  12. Shoeb Ahmad S, Abdul Ghani S, Hemalata Rajagopal T
    J Curr Glaucoma Pract, 2013 May-Aug;7(2):49-53.
    PMID: 26997782 DOI: 10.5005/jp-journals-10008-1137
    Glaucoma is now regarded as a neurodegenerative disorder. A number of theories including the mechanical and vascular models have been used to explain the pathogenesis of glaucoma. However, there is now increasing evidence of biochemical molecules which may play a part in it's causation. These biochemical mechanisms include the role of excitatory aminoacids, caspases, protein kinases, oxygen free radicals, nitric oxide, TNF-alpha, neurotrophins and metalloproteins. This paper reviews these new developments which form the biochemical basis of glaucomatous neural degeneration. How to cite this article: Ahmad SS, Ghani SA, Rajagopal TH. Current Concepts in the Biochemical Mechanisms of Glaucomatous Neurodegeneration. J Current Glau Prac 2013;7(2):49-53.
  13. Lim PS, Shafiee MN, Ahmad S, Hashim Omar M
    Sex Reprod Healthc, 2012 Jun;3(2):95-6.
    PMID: 22578758 DOI: 10.1016/j.srhc.2012.03.002
    A 33 year-old woman had an emergency caesarean section for retained second twin which was complicated by utero-cutaneous fistula due to red degeneration of intramural fibroid. The utero-cutaneous communication was demonstrated by an examination under anaesthesia using dye test. She then underwent excision of the fistula tract and myomectomy. She recovered well following the surgery. This is the first case of utero-cutaneous fistula where the communication is between the endometrial cavity and skin lesion via a necrotic intramural fibroid following caesarean section. Fistulogram might fail to demonstrate the communication. In highly suspected case, other modalities of investigations could be utilised.
  14. Rahman RA, Ahmad S, Ismail NA, Mahdy ZA
    J Reprod Med, 2012 Sep-Oct;57(9-10):456-8.
    PMID: 23091998
    The incidence of a coexistent normal fetus is quoted in literature as 1 in 22,000 to 100,000 pregnancies and may be associated with multiple complications including persistent trophoblastic neoplasia.
  15. Hendra R, Ahmad S, Oskoueian E, Sukari A, Shukor MY
    PMID: 22070850 DOI: 10.1186/1472-6882-11-110
    Phaleria macrocarpa (Scheff.) Boerl (Thymelaceae) originates from Papua Island, Indonesia and grows in tropical areas. The different parts of the fruit of P. macrocarpa were evaluated for antioxidant, anti-inflammatory, and cytotoxic activities.
  16. Hendra R, Ahmad S, Sukari A, Shukor MY, Oskoueian E
    Int J Mol Sci, 2011;12(6):3422-31.
    PMID: 21747685 DOI: 10.3390/ijms12063422
    Phaleria macrocarpa (Scheff.) Boerl (Thymelaceae) is commonly known as 'Crown of God', 'Mahkota Dewa', and 'Pau'. It originates from Papua Island, Indonesia and it grows in tropical areas. Empirically, it is potent in treating the hypertensive, diabetic, cancer and diuretic patients. It has a long history of ethnopharmacological usage, and the lack of information about its biological activities led us to investigate the possible biological activities by characterisation of flavonoids and antimicrobial activity of various part of P. macrocarpa against pathogenic bacteria and fungi. The results showed that kaempferol, myricetin, naringin, and rutin were the major flavonoids present in the pericarp while naringin and quercetin were found in the mesocarp and seed. Furthermore, the antibacterial activity of different parts of P. macrocarpa fruit showed a weak ability to moderate antibacterial activity against pathogenic tested bacteria (inhibition range: 0.93-2.17 cm) at concentration of 0.3 mg/disc. The anti fungi activity was only found in seed extract against Aspergillus niger (1.87 cm) at concentration of 0.3 mg/well. From the results obtained, P. macrocarpa fruit could be considered as a natural antimicrobial source due to the presence of flavonoid compounds.
  17. Mughir AM, Yusof MI, Abdullah S, Ahmad S
    Surg Radiol Anat, 2010 Jul;32(6):587-92.
    PMID: 20047027 DOI: 10.1007/s00276-009-0612-x
    To study the morphological difference between the lumbar pedicle in adolescent and adult groups as only less information is known about their pedicle morphology, especially in Malaysian population.
  18. Naim NM, Mahdy ZA, Ahmad S, Razi ZR
    Aust N Z J Obstet Gynaecol, 2007 Apr;47(2):132-6.
    PMID: 17355303 DOI: 10.1111/j.1479-828X.2007.00699.x
    OBJECTIVE: To compare the effectiveness of the Vabra aspirator and the Pipelle device as an outpatient endometrial assessment tool.
    METHOD: This was a randomised, prospective trial conducted for a period of one year.
    RESULTS: A total of 147 patients were recruited, of which 71 were in the Vabra group and 76 were in the Pipelle arm. The procedure success rate in the Pipelle group was significantly higher than the Vabra arm (98.7 vs 88.7%, P=0.02). Adequate tissue yield was also significantly more in the Pipelle arm (73.3 vs 52.4%, P=0.02). Cost-benefit analysis revealed a higher average cost per patient in the Vabra group compared to the Pipelle arm.
    CONCLUSION: This study proved that the Vabra aspirator was not as effective as the Pipelle device in obtaining endometrial tissue for histological diagnosis. Despite its higher price per unit, the Pipelle device was a more cost-effective tool for outpatient endometrial assessment.
    Study site: Medical clinic, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia.
  19. Raih MF, Ahmad S, Zheng R, Mohamed R
    Biophys Chem, 2005 Apr 1;114(1):63-9.
    PMID: 15792862
    A non-redundant database of 4536 structural domains, comprising more than 790,000 residues, has been used for the calculation of their solvent accessibility in the native protein environment and then in the isolated domain environment. Nearly 140,000 (18%) residues showed a change in accessible surface area in the above two conditions. General features of this change under these two circumstances have been pointed out. Propensities of these interfacing amino acid residues have been calculated and their variation for different secondary structure types has been analyzed. Actual amount of surface area lost by different secondary structures is higher in the case of helix and strands compared to coil and other conformations. Overall change in surface area in hydrophobic and uncharged residues is higher than that in charged residues. An attempt has been made to know the predictability of interface residues from sequence environments. This analysis and prediction results have significant implications towards determining interacting residues in proteins and for the prediction of protein-protein, protein-ligand, protein-DNA and similar interactions.
  20. Altalmas T, Aula A, Ahmad S, Tokhi MO, Akmeliawati R
    Assist Technol, 2016;28(3):159-74.
    PMID: 27187763 DOI: 10.1080/10400435.2016.1140688
    Two-wheeled wheelchairs are considered highly nonlinear and complex systems. The systems mimic a double-inverted pendulum scenario and will provide better maneuverability in confined spaces and also to reach higher level of height for pick and place tasks. The challenge resides in modeling and control of the two-wheeled wheelchair to perform comparably to a normal four-wheeled wheelchair. Most common modeling techniques have been accomplished by researchers utilizing the basic Newton's Laws of motion and some have used 3D tools to model the system where the models are much more theoretical and quite far from the practical implementation. This article is aimed at closing the gap between the conventional mathematical modeling approaches where the integrated 3D modeling approach with validation on the actual hardware implementation was conducted. To achieve this, both nonlinear and a linearized model in terms of state space model were obtained from the mathematical model of the system for analysis and, thereafter, a 3D virtual prototype of the wheelchair was developed, simulated, and analyzed. This has increased the confidence level for the proposed platform and facilitated the actual hardware implementation of the two-wheeled wheelchair. Results show that the prototype developed and tested has successfully worked within the specific requirements established.
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