Publications by authors named "Mohammed Rafiq Abdul Kadir"

59 Publications

Effects of badminton insole design on stress distribution, displacement and bone rotation of ankle joint during single-leg landing: a finite element analysis.

Sports Biomech 2022 Jun 20:1-22. Epub 2022 Jun 20.

Bioinspired Devices and Tissue Engineering (BIOINSPIRA) Research Group, School of Biomedical Engineering and Health Sciences, Faculty of Engineering, Universiti Teknologi Malaysia, Johor Bahru, Malaysia.

Previous research has reported that up to 92% of injuries amongst badminton players consist of lower limb, whereby 35% of foot fractures occurred at the metatarsal bone. In sports, insoles are widely used to increase athletes' performance and prevent many injuries. However, there is still a lack of badminton insole analysis and improvements. Therefore, this study aimed to biomechanically analyse three different insole designs. A validated and converged three-dimensional (3D) finite element model of ankle-foot complex was developed, which consisted of the skin, talus, calcaneus, navicular, three cuneiform, cuboid, five metatarsals and five phalanges. Three existing insoles from the market, (1) Yonex Active Pro Truactive, (2) Victor VT-XD 8 and (3) Li-Ning L6200LA, were scanned using a 3D scanner. For the analysis, single-leg landing was simulated. On the superior surface of the skin, 2.57 times of the bodyweight was axially applied, and the inferior surface of the outsole was fixed. The results showed that Insole 3 was the most optimum design to reduce peak stress on the metatarsals (3.807 MPa). In conclusion, the optimum design of Insole 3, based on the finite element analysis, could be a justification of athletes' choices to prevent injury and other complications.
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http://dx.doi.org/10.1080/14763141.2022.2086168DOI Listing
June 2022

Biomechanical effects of cross-pin's diameter in reconstruction of anterior cruciate ligament - A specific case study via finite element analysis.

Injury 2022 Jul 19;53(7):2424-2436. Epub 2022 May 19.

Bioinspired Devices and Tissue Engineering (BIOINSPIRA) Research Group, School of Biomedical Engineering and Health Sciences, Faculty of Engineering, Universiti Teknologi Malaysia, 81310, Johor Bahru, Johor, Malaysia; Sports Innovation and Technology Centre (SITC), Institute of Human Centered Engineering (iHumEn), Universiti Teknologi Malaysia, 81310, Johor Bahru, Johor, Malaysia.

For anterior cruciate ligament reconstruction (ACL-R), one of the crucial aspects of treatment is the fixator selection that could provide initial graft fixation post-operatively. Literature on biomechanical stabilities of different sizes of fixators as femoral graft fixation is limited. Therefore, this study aims to analyse the influence of different diameters of cross-pins on the stability of graft fixations after ACL-R via finite element analysis (FEA). In the methodology, three-dimensional (3D) models of three different diameters of cross-pins were developed, of which anterior tibial loads (ATL) were applied onto the tibia. From the findings, the cross-pin with a smaller diameter (4 mm) provided optimum stability than larger diameter cross-pins, whereby it demonstrated acceptable stresses at the fixators (both cross-pin and interference screw) with a different percentage of 28%, while the stresses at the corresponding bones were favourable for osseointegration to occur. Besides, the strains of the knee joint with 4 mm diameter cross-pin were also superior in providing a good biomechanical environment for bone healing, while the recorded strain values at fixators were comparable with a larger diameter of cross-pins without being inferior in terms of deformation. To conclude, the cross-pin with 4 mm diameter depicted the best biomechanical aspects in graft fixation for ACL-R since it allows better assistance for the osseointegration process and can minimise the possibility of the breakage and migration of fixators. This study is not only useful for medical surgeons to justify their choices of pin diameter to treat patients, but also for researchers to conduct future studies.
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http://dx.doi.org/10.1016/j.injury.2022.05.021DOI Listing
July 2022

Correction: Development and evaluation of κ-carrageenan based polymeric hybrid nanocomposite scaffolds for bone tissue engineering.

RSC Adv 2021 May 24;11(30):18615-18616. Epub 2021 May 24.

Department of Biology, College of Sciences, University of Hafr Al Batin 39524 Hafar Al-batin Saudi Arabia

[This corrects the article DOI: 10.1039/D0RA07446B.].
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http://dx.doi.org/10.1039/d1ra90119bDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9033475PMC
May 2021

Biomechanical analysis of three different types of fixators for anterior cruciate ligament reconstruction via finite element method: a patient-specific study.

Med Biol Eng Comput 2021 Sep 15;59(9):1945-1960. Epub 2021 Aug 15.

Medical Devices & Technology Centre (MEDiTEC), Institute of Human Centered Engineering (iHumEn), Universiti Teknologi Malaysia, 81310, Johor Bahru, Johor, Malaysia.

Complication rates of anterior cruciate ligament reconstruction (ACL-R) were reported to be around 15% although it is a common arthroscopic procedure with good outcomes. Breakage and migration of fixators are still possible even months after surgery. A fixator with optimum stability can minimise those two complications. Factors that affect the stability of a fixator are its configuration, material, and design. Thus, this paper aims to analyse the biomechanical effects of different types of fixators (cross-pin, interference screw, and cortical button) towards the stability of the knee joint after ACL-R. In this study, finite element modelling and analyses of a knee joint attached with double semitendinosus graft and fixators were carried out. Mimics and 3-Matic softwares were used in the development of the knee joint models. Meanwhile, the graft and fixators were designed by using SolidWorks software. Once the meshes of all models were finished in 3-Matic, simulation of the configurations was done using MSC Marc Mentat software. A 100-N anterior tibial load was applied onto the tibia to simulate the anterior drawer test. Based on the findings, cross-pin was found to have optimum stability in terms of stress and strain at the femoral fixation site for better treatment of ACL-R.
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http://dx.doi.org/10.1007/s11517-021-02419-6DOI Listing
September 2021

Non-obstructive monitoring of muscle fatigue for low intensity dynamic exercise with infrared thermography technique.

Med Biol Eng Comput 2021 Aug 22;59(7-8):1447-1459. Epub 2021 Jun 22.

School of Biomedical Engineering and Health Sciences, Faculty of Engineering, Universiti Teknologi Malaysia, 81310, Johor Bahru, Johor, Malaysia.

Surface electromyography (sEMG) has been widely used in evaluating muscle fatigue among athletes where electrodes are attached on the skin during the activity. Recently, infrared thermography technique (IRT) has gain popularity and shown to be another preferred method in monitoring and predicting muscle fatigue non-obstructively. This paper investigates the correlation between surface temperature and muscle activation parameters obtained using both IRT and sEMG methods simultaneously. Twenty healthy subjects were required to perform a repetitive calf raise exercise with various loads attached around their ankle for 3 min to induce fatigue on the targeted gastrocnemius muscles. Average temperature and temperature difference information were extracted from thermal images, while root mean square (RMS) and median frequency (MF) were extracted from sEMG signals. Spearman statistical analysis performed shows that there is a significant correlation between average temperature with RMS and between temperature difference with MF values at p<0.05. While ANOVA test conducted shows that there is significant impact of loads on RMS and MF where F=12.61 and 3.59, respectively, at p< 0.05. This study suggested that skin surface temperature can be utilized in monitoring and predicting muscle fatigue in low intensity dynamic exercise and can be extended to other dynamic exercises.
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http://dx.doi.org/10.1007/s11517-021-02387-xDOI Listing
August 2021

Vitamin D-loaded electrospun cellulose acetate/polycaprolactone nanofibers: Characterization, in-vitro drug release and cytotoxicity studies.

Int J Biol Macromol 2021 Jun 23;181:82-98. Epub 2021 Mar 23.

Faculty of Engineering Technology, Universiti Tun Hussein Onn Malaysia, 86400 Batu Pahat, Malaysia.

Vitamin D deficiency is now a global health problem; despite several drug delivery systems for carrying vitamin D due to low bioavailability and loss bioactivity. Developing a new drug delivery system to deliver vitamin D is a strong incentive in the current study. Hence, an implantable drug delivery system (IDDS) was developed from the electrospun cellulose acetate (CA) and ε-polycaprolactone (PCL) nanofibrous membrane, in which the core of implants consists of vitamin D-loaded CA nanofiber (CAVD) and enclosed in a thin layer of the PCL membrane (CAVD/PCL). CA nanofibrous mat loaded with vitamin D at the concentrations of 6, 12, and 20% (w/w) of vitamin D were produced using electrospinning. The smooth and bead-free fibers with diameters ranged from 324 to 428 nm were obtained. The fiber diameters increased with an increase in vitamin D content. The controlled drug release profile was observed over 30-days, which fit with the zero-order model (R > 0.96) in the first stage. The mechanical properties of IDDS were improved. Young's modulus and tensile strength of CAVD/PCL (dry) were161 ± 14 and 13.07 ± 2.5 MPa, respectively. CA and PCL nanofibers are non-cytotoxic based on the results of the in-vitro cytotoxicity studies. This study can further broaden in-vivo study and provide a reference for developing a new IDDS to carry vitamin D in the future.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.03.108DOI Listing
June 2021

The effects of additional hollow cylinder coated to external fixator screws for treating pilon fracture: A biomechanical perspective.

Injury 2021 Aug 9;52(8):2131-2141. Epub 2021 Mar 9.

Bioinpired Devices and Tissue Engineering (BIOINSPIRA) Research Group, School of Biomedical Engineering and Health Sciences, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), 81310 Johor Bahru, Johor, Malaysia; Sports Innovation and Technology Centre (SITC), Institute of Human Centered Engineering (iHumEn), Universiti Teknologi Malaysia (UTM), 81310 Johor Bahru, Johor, Malaysia. Electronic address:

An external fixator is a promising medical device that could provide optimum stability and reduce the rate of complications in treating bone fracture during intervention period. It is noted that the biomechanics behaviour of device can be altered by introducing more features such as material suitability and additional components. Therefore, this study was conducted via finite element method to investigate the effects of additional hollow cylinder coated with external fixator screws in treating Type III pilon fracture. Finite element models which have been validated with experimental data were used to simulate stresses at the pin-bone interface and relative micromovement at interfragmentary fractures during swing (70 N load) and stance phases (350 N load). All bones and external fixators were assigned with isotropic material properties while the cartilages were simulated with hyper-elastic. For the hollow cylinder, polyethylene was assigned due to its properties which are equivalent to the bone. From the results, it is found that stresses at the pin-bone interface for the coated screws were reduced to 54% as compared to the conventional fixator. For the micromovement, there was no difference between both models, whereby the value was 0.03 mm. The results supported previously published literature, in which high stresses are unavoidable at the interface, fortunately, those stresses did not exceed the ultimate strength of bone, which is safe for treating patients. In conclusion, if patients are allowed to bear weight bearing, the external fixator with coated screws is a more favourable option to be fixed into the bone to avoid complications at the interface.
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http://dx.doi.org/10.1016/j.injury.2021.03.017DOI Listing
August 2021

Effects of Blood Flow Restriction Training on Muscle Strength and Pain in Patients With Knee Injuries: A Meta-Analysis.

Am J Phys Med Rehabil 2021 04;100(4):337-344

From the Exercise and Sports Science Programme, School of Health Sciences, Universiti Sains Malaysia, Kelantan, Malaysia (SL, SS); and School of Biomedical Engineering & Health Sciences, Faculty of Engineering, Universiti Teknologi Malaysia, Johor, Malaysia (MRAK).

Background: Due to the pain caused by knee injuries, low-load resistance training with blood flow restriction (L-BFR) may be a potential adjuvant therapeutic tool in the rehabilitation of knee injuries. This review aimed to analyze the effectiveness of L-BFR training modality in knee rehabilitation.

Design: A meta-analysis was conducted to determine the potential impact of blood flow restriction on patients with knee injuries. PubMed, EBSCO, and Web of Science databases were searched for eligible studies from January 2000 until January 2020. The mean differences of the data were analyzed using Revman 5.3 software with a 95% confidence interval.

Results: Nine studies fulfilled the inclusion criteria. These studies involved 179 patients who received L-BFR, 96 patients who underwent high-load resistance training, and another 94 patients who underwent low-load resistance training. The analysis of pooled data showed that patients in both the L-BFR (standardized mean difference, 0.83 [0.53, 1.14], P < 0.01) and high-load resistance training (standardized mean difference, -0.09 [-0.43, 0.24], P = 0.58) groups experienced an increase in muscle strength after the training. In addition, pain score was significantly reduced in the L-BFR group compared with the other two groups (standardized mean difference, -0.61 [-1.19, -0.03], P = 0.04).

Conclusions: Muscle strength increased after L-BFR and high-load resistance training compared with low-load resistance training. Furthermore, pain score was significantly reduced after L-BFR. Hence, L-BFR is a potential intervention to be applied in rehabilitation of knee injuries.
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http://dx.doi.org/10.1097/PHM.0000000000001567DOI Listing
April 2021

Effects of conform, non-conform, and hybrid conformity toward stress distribution at the glenoid implant and cement: A finite element study.

Int J Artif Organs 2022 Feb 1;45(2):200-206. Epub 2021 Mar 1.

Medical Devices and Technology Centre, Institute of Human Centered Engineering, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia.

Glenoid conformity is one of the important aspects that could contribute to implant stability. However, the optimal conformity is still being debated among the researchers. Therefore, this study aims to analyze the stress distribution of the implant and cement in three types of conformity (conform, non-conform, and hybrid) in three load conditions (central, anterior, and posterior). Glenoid implant and cement were reconstructed using Solidwork software and a 3D model of scapula bone was done using MIMICS software. Constant load, 750 N, was applied at the central, anterior, and posterior region of the glenoid implant which represents average load for daily living activities for elder people, including, walking with a stick and standing up from a chair. The results showed that, during center load, an implant with dual conformity (hybrid) showed the best (Max Stress-3.93 MPa) and well-distributed stress as compared to other conformity (Non-conform-7.21 MPa, Conform-9.38 MPa). While, during eccentric load (anterior and posterior), high stress was located at the anterior and posterior region with respect to the load applied. Cement stress for non-conform and hybrid implant recorded less than 5 MPa, which indicates it had a very low risk to have cement microcracks, whilst, conform implant was exposed to microcrack of the cement. In conclusion, hybrid conformity showed a promising result that could compromise between conform and non-conform implant. However, further enhancement is required for hybrid implants when dealing with eccentric load (anterior and posterior).
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http://dx.doi.org/10.1177/0391398821999391DOI Listing
February 2022

Synthesis and Characterization of Silver-Coated Polymeric Scaffolds for Bone Tissue Engineering: Antibacterial and In Vitro Evaluation of Cytotoxicity and Biocompatibility.

ACS Omega 2021 Feb 2;6(6):4335-4346. Epub 2021 Feb 2.

Department of Biology, College of Sciences, University of Hafr Al Batin, 39524 Hafar Al-batin, Saudi Arabia.

In bone tissue engineering, multifunctional composite materials are very challenging. Bone tissue engineering is an innovative technique to develop biocompatible scaffolds with suitable orthopedic applications with enhanced antibacterial and mechanical properties. This research introduces a polymeric nanocomposite scaffold based on arabinoxylan--acrylic acid, nano-hydroxyapatite (nHAp), nano-aluminum oxide (nAlO), and graphene oxide (GO) by free-radical polymerization for the development of porous scaffolds using the freeze-drying technique. These polymeric nanocomposite scaffolds were coated with silver (Ag) nanoparticles to improve antibacterial activities. Together, nHAp, nAlO, and GO enhance the multifunctional properties of materials, which regulate their physicochemical and biomechanical properties. Results revealed that the Ag-coated polymeric nanocomposite scaffolds had excellent antibacterial properties and better microstructural properties. Regulated morphological properties and maximal antibacterial inhibition zones were found in the porous scaffolds with the increasing amount of GO. Moreover, the nanosystem and the polymeric matrix have improved the compressive strength (18.89 MPa) and Young's modulus (198.61 MPa) of scaffolds upon increasing the amount of GO. The biological activities of the scaffolds were investigated against the mouse preosteoblast cell lines (MC3T3-E1) and increasing the quantities of GO helps cell adherence and proliferation. Therefore, our findings showed that these silver-coated polymeric nanocomposite scaffolds have the potential for engineering bone tissue.
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http://dx.doi.org/10.1021/acsomega.0c05596DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7893789PMC
February 2021

Arabinoxylan/graphene-oxide/nHAp-NPs/PVA bionano composite scaffolds for fractured bone healing.

J Tissue Eng Regen Med 2021 04 9;15(4):322-335. Epub 2021 Mar 9.

Sustainable Energy Technologies Center, College of Engineering, King Saud University, Riyadh, Saudi Arabia.

The importance of bone scaffolds has increased many folds in the last few years; however, during bone implantation, bacterial infections compromise the implantation and tissue regeneration. This work is focused on this issue while not compromising on the properties of a scaffold for bone regeneration. Biocomposite scaffolds (BS) were fabricated via the freeze-drying technique. The samples were characterized for structural changes, surface morphology, porosity, and mechanical properties through spectroscopic (Fourier transform-infrared [FT-IR]), microscopic (scanning electron microscope [SEM]), X-ray (powder X-ray diffraction and energy-dispersive X-ray), and other analytical (Brunauer-Emmett-Teller, universal testing machine Instron) techniques. Antibacterial, cellular, and hemocompatibility assays were performed using standard protocols. FT-IR confirmed the interactions of all the components. SEM illustrated porous and interconnected porous morphology. The percentage porosity was in the range of 49.75%-67.28%, and the pore size was 215.65-470.87 µm. The pore size was perfect for cellular penetration. Thus, cells showed significant proliferation onto these scaffolds. X-ray studies confirmed the presence of nanohydroxyapatite and graphene oxide (GO). The cell viability was 85%-98% (BS1-BS3), which shows no significant toxicity of the biocomposite. Furthermore, the biocomposites exhibited better antibacterial activity, no effect on the blood clotting (normal in vitro blood clotting), and less than 5% hemolysis. The ultimate compression strength for the biocomposites increased from 4.05 to 7.94 with an increase in the GO content. These exciting results revealed that this material has the potential for possible application in bone tissue engineering.
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http://dx.doi.org/10.1002/term.3168DOI Listing
April 2021

Development and evaluation of κ-carrageenan based polymeric hybrid nanocomposite scaffolds for bone tissue engineering.

RSC Adv 2020 11 6;10(66):40529-40542. Epub 2020 Nov 6.

Department of Biology, College of Sciences, University of Hafr Al Batin 39524 Hafar Al-batin Saudi Arabia

The excellent biocompatible and osteogenesis characteristics of porous scaffolds play a vital role in bone regeneration. In this study, we have synthesized polymeric hybrid nanocomposites free-radical polymerization from carrageenan/acrylic-acid/graphene/hydroxyapatite. Porous hybrid nanocomposite scaffolds were fabricated through a freeze-drying method to mimic the structural and chemical composition of natural bone. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and water contact-angle studies were carried-out for functional groups, surface morphology and hydrophilicity of the materials, followed by biodegradation and swelling analysis. The cell viability, cell culture and proliferation were evaluated against mouse pre-osteoblast () cell lines using neutral red dye assay. The cell adherence and proliferation studies were determined by SEM. Physical characterization including optimum porosity and pore size (49.75% and 0.41 × 10 μm), mechanical properties (compression strength 8.87 MPa and elastic modulus 442.63 MPa), swelling (70.20% at 27 °C and 77.21% at 37 °C) and biodegradation (23.8%) were performed. The results indicated CG--AAc-3 with a high optical density and better cell viability. Hence, CG--AAc-3 was found to be more efficient for bone regeneration with potential applications in fractured bone regeneration.
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http://dx.doi.org/10.1039/d0ra07446bDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9057573PMC
November 2020

Biomechanical evaluation of three different configurations of external fixators for treating distal third tibia fracture: Finite element analysis in axial, bending and torsion load.

Comput Biol Med 2020 12 17;127:104062. Epub 2020 Oct 17.

Medical Devices and Technology Centre (MEDiTEC), Institute of Human Centered Engineering (iHumEn), Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia; Bioinspired Devices and Tissue Engineering (BIOINSPIRA) Group, School of Biomedical Engineering & Health Sciences, Faculty of Engineering, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia. Electronic address:

External fixators have been widely used in treating open fractures and have produced excellent outcomes, as they could successfully heal bones. The stability of external fixators lies greatly in their construction. Factors that associated with the stability of the external fixators includes stress, displacement, and relative micromotion. Three-dimensional (3D) models of bone and external fixators were constructed by using 3D modelling software, namely Materialise and SolidWorks, respectively. Three different configurations of external fixators namely Model 1, Model 2, and Model 3 were analysed. Three load cases were simulated to assess the abovementioned factors at the bone, specifically at the fracture site and at the external fixator. Findings showed that the double-cross configuration (Model 3) was the most promising in axial, bending, and torsion load cases as compared to the other two configurations. The no-cross configuration (Model 1) had the highest risk of complication due to high stress, relative micromotion, and displacement in the bending and torsion load cases. On the other hand, the single-cross configuration (Model 2) had the highest risk of complication when applied with axial load. In conclusion, the double-cross locking construct (Model 3) showed the biggest potential to be a new option for medical surgeons in treating patients associated with bone fracture. This new double-cross locking construct showed superior biomechanical stability as compared to single-cross and no-cross configurations in the axial, bending, and torsion load cases.
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http://dx.doi.org/10.1016/j.compbiomed.2020.104062DOI Listing
December 2020

A finite element study: Finding the best configuration between unilateral, hybrid, and ilizarov in terms of biomechanical point of view.

Injury 2020 Nov 2;51(11):2474-2478. Epub 2020 Aug 2.

Bioinspired Devices and Tissue Engineering (BIOINSPIRA) Group, School of Biomedical Engineering & Health Sciences, Faculty of Engineering, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia; Medical Devices and Technology Centre (MEDiTEC), Institute of Human Centered Engineering (iHumEn), Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia. Electronic address:

In an open fracture, the external fixator is one of the definitive treatment options as it could provide the initial stabilisation of the fractured bone. Limited literature discussing on the biomechanical stability between unilateral, hybrid and Ilizarov configurations, principally in treating a femoral fracture. Thus, this study aims to analyse the biomechanical stability of different external fixators via the finite element method (FEM). The present study portrays that different configurations of fixators possess different biomechanical stability, hence leading to different healing rates and complication risks. For the methodology, three-dimensional models of three different external fixators were reconstructed where axial loads were applied on the proximal end of the femur, simulating the stance phase. From the results, the unilateral configuration provides better stability compared to the hybrid and Ilizarov, where it displaced the least with an average percentage difference of 50% for the fixator's frame and 23% for the bone. The unilateral configuration also produced the least interfragmentary movement (0.48 mm) as compared to hybrid (0.62 mm) and Ilizarov (0.61 mm) configurations. Besides, the strain and stress of the unilateral configuration were superior in terms of stability compared to the other two configurations. As a conclusion, the unilateral configuration had the best biomechanical stability as it was able to assist the bone healing process as well as minimising the risk of pin tract infection while treating a femoral fracture.
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http://dx.doi.org/10.1016/j.injury.2020.08.001DOI Listing
November 2020

Novel functional antimicrobial and biocompatible arabinoxylan/guar gum hydrogel for skin wound dressing applications.

J Tissue Eng Regen Med 2020 10 17;14(10):1488-1501. Epub 2020 Aug 17.

School of Biological Sciences, University of the Punjab, Lahore, Pakistan.

It is a challenging task to develop active biomacromolecular wound dressing materials that are biocompatible and possesses antibacterial properties against the bacterial strains that cause severe skin disease. This work is focused on the preparation of a biocompatible and degradable hydrogel for wound dressing application using arabinoxylan (ARX) and guar gum (GG) natural polymers. Fourier transform infrared spectroscopy (FT-IR) confirmed that both ARX and GG interacted well with each other, and their interactions further increased with the addition of crosslinker tetraethyl orthosilicate. Scanning electron microscope (SEM) micrographs showed uniform porous morphologies of the hydrogels. The porous morphologies and uniform interconnected pores are attributed to the increased crosslinking of the hydrogel. Elastic modulus, tensile strength, and fracture strain of the hydrogels significantly improved (from ATG-1 to ATG-4) with crosslinking. Degradability tests showed that hydrogels lost maximum weight in 7 days. All the samples showed variation in swelling with pH. Maximum swelling was observed at pH 7. The hydrogel samples showed good antibacterial activity against Pseudomonas aeruginosa (Gram-negative) and Staphylococcus aureus (Gram-positive) in PBS, good drug release profile (92% drug release), and nontoxic cellular behavior. The cells not only retained their cylindrical morphologies onto the hydrogel but were also performing their normal activities. It is, therefore, believed that as-developed hydrogel could be a potential material for wound dressing application.
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http://dx.doi.org/10.1002/term.3115DOI Listing
October 2020

Stress Distributions and Micromovement of Fragment Bone of Pilon Fracture Treated With External Fixator: A Finite Element Analysis.

J Foot Ankle Surg 2020 Jul - Aug;59(4):664-672

Professor, Sports Innovation and Technology Centre (SITC), Institute of Human Centered Engineering (iHumEn), Universiti Teknologi Malaysia, Johor, Malaysia.

Osteoporosis and osteoarthritis are common pathological problems of the human bone tissue. There are some cases of pilon fractures associated with these 2 pathological conditions. In terms of treatment, for a normal and healthy bone with pilon fracture, the use of the Delta external fixator is a favorable option because it can allow early mobilization for patients and provide stability for the healing process. However, the stability of the external fixator differs when there is low bone stiffness, which has not been previously investigated. Therefore, this study was conducted to determine the stability of the external fixator to treat pilon fracture associated with osteoporosis and osteoarthritis, particularly to differentiate the stress distribution and micromovement of fracture fragment. Three-dimensional finite element models of the ankle and foot bones were reconstructed based on the computed tomography datasets. The bones consisted of 5 metatarsal, 3 cuneiform, and 1 each of cuboid, navicular, calcaneus, talus, fibula, and tibia bones. They were assigned with linear isotropic behavior. The ankle joint consisted of ligament and cartilage, and they were assigned with the use of linear links and the Mooney-Rivlin model, respectively. During simulation of the gait cycle, 70 N and 350 N were applied axially to the tibia bone to represent the swing and stance phases, respectively. The metatarsal and calcaneus bones were fixed to prevent any movement of the rigid body. The study found that the greatest von Mises stress value was observed at the pin-bone interface for the osteoporosis (108 MPa) model, followed by the osteoarthritis (87 MPa) and normal (44 MPa) models, during the stance phase. For micromovement, the osteoporosis model had the largest value at 0.26 mm, followed by the osteoarthritis (0.09 mm) and normal (0.03 mm) models. In conclusion, the greatest magnitudes of stress and micromovement were observed for the osteoporosis bone and extra care should be taken to treat pilon fracture associated with this pathological condition.
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http://dx.doi.org/10.1053/j.jfas.2019.09.006DOI Listing
June 2021

Synthesis of Silver-Coated Bioactive Nanocomposite Scaffolds Based on Grafted Beta-Glucan/Hydroxyapatite via Freeze-Drying Method: Anti-Microbial and Biocompatibility Evaluation for Bone Tissue Engineering.

Materials (Basel) 2020 Feb 21;13(4). Epub 2020 Feb 21.

Department of Biology, University of Hafr Al Batin, Hafar Al-batin 39524, Saudi Arabia.

Advancement and development in bone tissue engineering, particularly that of composite scaffolds, are of great importance for bone tissue engineering. We have synthesized polymeric matrix using biopolymer (β-glucan), acrylic acid, and nano-hydroxyapatite through free radical polymerization method. Bioactive nanocomposite scaffolds (BNSs) were fabricated using the freeze-drying method and Ag was coated by the dip-coating method. The scaffolds have been characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction analysis (XRD) to investigate their functional groups, surface morphology, and phase analysis, respectively. The pore size and porosity of all BNS samples were found to be dependent on silver concentration. Mechanical testing of all BNS samples have substantial compressive strength in dry form that is closer to cancellous bone. The samples of BNS showed substantial antibacterial effect against DH5 alpha . The biological studies conducted using the MC3T3-E1 cell line via neutral red dye assay on the scaffolds have found to be biocompatible and non-cytotoxic. These bioactive scaffolds can bring numerous applications for bone tissue repairs and regenerations.
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http://dx.doi.org/10.3390/ma13040971DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7078890PMC
February 2020

Arabinoxylan-co-AA/HAp/TiO nanocomposite scaffold a potential material for bone tissue engineering: An in vitro study.

Int J Biol Macromol 2020 May 17;151:584-594. Epub 2020 Feb 17.

Department of Biological Sciences, National University of Medical Sciences, Rawalpindi, Punjab, Pakistan. Electronic address:

Arabinoxylan (AX) is a natural biological macromolecule with several potential biomedical applications. In this research, AX, nano-hydroxyapatite (n-HAp) and titanium dioxide (TiO) based polymeric nanocomposite scaffolds were fabricated by the freeze-drying method. The physicochemical characterizations of these polymeric nanocomposite scaffolds were performed for surface morphology, porosity, swelling, biodegradability, mechanical, and biological properties. The scaffolds exhibited good porosity and rough surface morphology, which were efficiently controlled by TiO concentrations. MC3T3-E1 cells were employed to conduct the biocompatibility of these scaffolds. Scaffolds showed unique biocompatibility in vitro and was favorable for cell attachment and growth. PNS3 proved more biocompatible, showed interconnected porosity and substantial mechanical strength compared to PNS1, PNS2 and PNS4. Furthermore, it has also showed more affinity to cells and cell growth. The results illustrated that the bioactive nanocomposite scaffold has the potential to find applications in the tissue engineering field.
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http://dx.doi.org/10.1016/j.ijbiomac.2020.02.142DOI Listing
May 2020

study of glenoid perforation during total shoulder arthroplasty: the effects on stress & micromotion.

Comput Methods Biomech Biomed Engin 2020 Apr 7;23(5):182-190. Epub 2020 Jan 7.

Department of Biomedical Engineering, School of Biomedical Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia.

Glenoid perforation is not the intended consequence of the surgery and must be avoided. The analysis on biomechanical aspect of glenoid vault perforation remains unknown. The purpose of this study is to determine the impact of glenoid perforation towards stress distribution and micromotion at the interfaces. Eight glenoid implant models had been constructed with various size, number and type of fixation. A load of 750 N was applied to centre, superior-anterior and superior-posterior area. Implant perforation had minimal impact on stress distribution and micromotion at the interfaces. However, cement survival rate for implant without perforation was the highest with a difference of up to 37% compared to other perforated models. Besides that, implant fixation and high stresses at the implant had more of an impact on implant instability than implant perforation. As a conclusion, glenoid perforation did not influence the stress distribution and micromotion, but, it reduced cement survival rate and increase the stress critical volume.
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http://dx.doi.org/10.1080/10255842.2019.1709828DOI Listing
April 2020

Developing functionally graded PVA hydrogel using simple freeze-thaw method for artificial glenoid labrum.

J Mech Behav Biomed Mater 2019 03 26;91:406-415. Epub 2018 Dec 26.

Medical Devices Technology Centre (Meditec), Faculty of Engineering, School of Biomedical Engineering & Health Sciences, Universiti Teknologi Malaysia, 81310 Skudai, Johor, Malaysia. Electronic address:

Intact glenoid labrum is one of passive stabilizer for glenohumeral joint, which have various stiffness at different region. The aim of this study is to develop new artificial glenoid labrum from Polyvinyl Alcohol (PVA) hydrogel, which known as good biomaterial due to its biocompatibility and ability to tailor its modulus. PVA hydrogel was formed using freeze-thaw (FT) method and the stiffness of PVA was controlled by manipulating the concentration of PVA and number of FT cycles. Then, the gradual stiffness was formed using simple diffusion method by introducing the pre-freeze-and-thaw steps. The results showed 20% PVA with three FT cycles suit to highest stiffness of glenoid labrum while 10% PVA with three FT cycles suit to lowest stiffness of glenoid labrum. The functionally graded PVA hydrogel was then developed using the same method by diffusing two mixture (20% PVA and 10% PVA). Mechanical compression test showed, the highest modulus (0.41 MPa) found at the 20% PVA region and lowest modulus (0.1 MPa) found at 10% PVA region. While, at intermediate region, the compressive modulus was in between 20% and 10%, 0.2 MPa. The existence of gradual stiffness was further prove by checking crystallinity of material at each region using Differential Scanning Calorimetry (DSC) and Wide Angle X-ray Diffraction (WAXD). Microstructure of material was obtained from Scanning Electron Microscopy (SEM). This functionally graded PVA hydrogel also able to reduce about 51% of stress at glenoid implant and up to 17% for micromotion at the interfaces. Existence of artificial glenoid labrum could minimize the occurrence of glenoid component loosening.
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http://dx.doi.org/10.1016/j.jmbbm.2018.12.033DOI Listing
March 2019

Enhancement of the Mechanical Properties of Hydroxyapatite/Sulphonated Poly Ether Ether Ketone Treated Layer for Orthopaedic and Dental Implant Application.

Int J Biomater 2018 1;2018:9607195. Epub 2018 Aug 1.

Bio-Medical Engineering Center, University of Engineering and Technology (UET), Lahore Kala Shah Kaku (KSK) Campus, Pakistan.

The mechanical properties of coated layers are one of the important factors for the long-term success of orthopeadic and dental implants. In this study, the mechanical properties of the porous coated layer were examined via scratch and nanoindentation tests. The effect of compression load on the porous coated layer of sulphonated poly ether ether ketone/Hydroxyapatite was studied to determine whether it changes its mechanical properties. The water contact angle and surface roughness of the compressed coated layer were also measured. The results showed a significant increase in elastic modulus, with mean values ranging from 0.464 GPa to 1.199 GPa (p<0.05). The average scratch hardness also increased significantly from 69.9 MPa to 95.7 MPa after compression, but the surface roughness and wettability decreased significantly (p<0.05). Simple compression enhanced the mechanical properties of the sulphonated poly ether ether ketone/hydroxyapatite coated layer, and the desired mechanical properties for orthopaedic and dental implant application can be achieved.
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http://dx.doi.org/10.1155/2018/9607195DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6093064PMC
August 2018

Polydopamine-assisted chlorhexidine immobilization on medical grade stainless steel 316L: Apatite formation and in vitro osteoblastic evaluation.

Ann Anat 2018 Nov 23;220:29-37. Epub 2018 Jul 23.

School of Biomedical Engineering & Health Sciences, Faculty of Engineering, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia; IJN-UTM Cardiovascular Engineering Centre, Institute of Human Centered Engineering, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia. Electronic address:

Immobilization of chlorhexidine (CHX) on stainless steel 316L (SS316L), assisted by a polydopamine film as an intermediate layer is projected as an approach in combating infection while aiding bone regeneration for coating development on orthopedic and dental implants. This study aimed to investigate the ability of CHX coating to promote apatite layer, osteoblast cells viability, adhesion, osteogenic differentiation and mineralization. Stainless steel 316L disks were pre-treated, grafted with a polydopamine film and immobilized with different concentrations of CHX (10-30mM). The apatite layer formation was determined through an in vitro simulated body fluid (SBF) test by ATR-FTIR and SEM-EDX analyses. The osteoblastic evaluations including cells viability, cells adhesion, osteogenic differentiation and mineralization were assessed with human fetal osteoblast cells through MTT assay, morphology evaluation under FESEM, ALP enzyme activity and Alizarin Red S assay. The apatite layer was successfully formed on the CHX coated disks, demonstrating potential excellent bioactivity property. The CHX coatings were biocompatible with the osteoblast cells at low CHX concentration (<20mM) with good adhesion on the metal surfaces. The increment of ALP activity and calcium deposition testified that the CHX coated disks able to support osteoblastic maturation and mineralization. These capabilities give a promising value to the CHX coating to be implied in bone regeneration area.
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http://dx.doi.org/10.1016/j.aanat.2018.06.009DOI Listing
November 2018

Influence of citric acid on the physical and biomineralization ability of freeze/thaw poly(vinyl alcohol) hydrogel.

J Biomater Appl 2018 07 1;33(1):94-102. Epub 2018 May 1.

5 School of Fundamental Science, Universiti Malaysia Terengganu, Kuala Terengganu, Terengganu, Malaysia.

This work reports the modification of freeze/thaw poly(vinyl alcohol) hydrogel using citric acid as the bioactive molecule for hydroxyapatite formation in simulated body fluid. Inclusion of 1.3 mM citric acid into the poly(vinyl alcohol) hydrogel showed that the mechanical strength, crystalline phase, functional groups and swelling ability were still intact. Adding citric acid at higher concentrations (1.8 and 2.3 mM), however, resulted in physically poor hydrogels. Presence of 1.3 mM of citric acid showed the growth of porous hydroxyapatite crystals on the poly(vinyl alcohol) surface just after one day of immersion in simulated body fluid. Meanwhile, a fully covered apatite layer on the poly(vinyl alcohol) surface plus the evidence of apatite forming within the hydrogel were observed after soaking for seven days. Gel strength of the soaked poly(vinyl alcohol)/citric acid-1.3 mM hydrogel revealed that the load resistance was enhanced compared to that of the neat poly(vinyl alcohol) hydrogel. This facile method of inducing rapid growth of hydroxyapatite on the hydrogel surface as well as within the hydrogel network can be useful for guided bone regenerative materials.
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http://dx.doi.org/10.1177/0885328218771195DOI Listing
July 2018

Biomechanical features of six design of the delta external fixator for treating Pilon fracture: a finite element study.

Med Biol Eng Comput 2018 Oct 21;56(10):1925-1938. Epub 2018 Apr 21.

Medical Devices and Technology Group (MEDITEG), Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia (UTM), 81310, Johor Bahru, Johor, Malaysia.

Pilon fractures can be caused by high-energy vertical forces which may result in long-term patient immobilization. Many experts in orthopedic surgery recommend the use of a Delta external fixator for type III Pilon fracture treatment. This device can promote immediate healing of fractured bone, minimizing the rate of complications as well as allowing early mobilization. The characteristics of different types of the Delta frame have not been demonstrated yet. By using the finite element method, this study was conducted to determine the biomechanical characteristics of six different configurations (Model 1 until Model 6). CT images from the lower limb of a healthy human were used to reconstruct three-dimensional models of foot and ankle bones. All bones were assigned with isotropic material properties and the cartilages were assigned to exhibit hyperelasticity. A linear link was used to simulate 37 ligaments at the ankle joint. Axial loads of 70 and 350 N were applied at the proximal tibia to simulate the stance and swing phase. The metatarsals and calcaneus were fixed distally in order to prevent rigid body motion. A synthetic ankle bone was used to validate the finite element model. The simulated results showed that Delta3 produced the highest relative micromovement (0.09 mm, 7 μm) during the stance and swing phase, respectively. The highest equivalent von Mises stress was found at the calcaneus pin of the Delta4 (423.2 MPa) as compared to others. In conclusion, Delta1 external fixator was the most favorable option for type III Pilon fracture treatment. Graphical abstract ᅟ.
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http://dx.doi.org/10.1007/s11517-018-1830-3DOI Listing
October 2018

In vitro selection and characterization of single stranded DNA aptamers for luteolin: A possible recognition tool.

Anal Biochem 2018 05 7;549:72-79. Epub 2018 Mar 7.

Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, Malaysia.

Distinctive bioactivities possessed by luteolin (3', 4', 5, 7-tetrahydroxy-flavone) are advantageous for sundry practical applications. This paper reports the in vitro selection and characterization of single stranded-DNA (ssDNA) aptamers, specific for luteolin (LUT). 76-mer library containing 1015 randomized ssDNA were screened via systematic evolution of ligands by exponential enrichment (SELEX). The recovered ssDNA pool from the 8th round was amplified with unlabeled primers and cloned into PSTBlue-1 vector prior to sequencing. 22 of LUT-binding aptamer variants were further classified into one of the seven groups based on their N40 random sequence regions, wherein one representative from each group was characterized. The dissociation constant of aptamers designated as LUT#28, LUT#20 and LUT#3 was discerned to be 107, 214 and 109 nM, respectively with high binding affinity towards LUT. Prediction analysis of the secondary structure suggested discrete features with typical loop and stem motifs. Furthermore, LUT#3 displayed higher specificity with insignificant binding toward kaempferol and quercetin despite its structural and functional similarity compared to LUT#28 and LUT#20. Further LUT#3 can detect free luteolin within 0.2-1 mM in solution. It was suggested that LUT#3 aptamer were the most suitable for LUT recognition tool at laboratory scale based on the condition tested.
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http://dx.doi.org/10.1016/j.ab.2018.03.004DOI Listing
May 2018

Finite element analysis of the wrist in stroke patients: the effects of hand grip.

Med Biol Eng Comput 2018 Jul 5;56(7):1161-1171. Epub 2017 Dec 5.

Medical Devices and Technology Group (MEDITEG), Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia (UTM), 81310, Johor Bahru, Malaysia.

The provision of the most suitable rehabilitation treatment for stroke patient remains an ongoing challenge for clinicians. Fully understanding the pathomechanics of the upper limb will allow doctors to assist patients with physiotherapy treatment that will aid in full arm recovery. A biomechanical study was therefore conducted using the finite element (FE) method. A three-dimensional (3D) model of the human wrist was reconstructed using computed tomography (CT)-scanned images. A stroke model was constructed based on pathological problems, i.e. bone density reductions, cartilage wane, and spasticity. The cartilages were reconstructed as per the articulation shapes in the joint, while the ligaments were modelled using linear links. The hand grip condition was mimicked, and the resulting biomechanical characteristics of the stroke and healthy models were compared. Due to the lower thickness of the cartilages, the stroke model reported a higher contact pressure (305 MPa), specifically at the MC1-trapezium. Contrarily, a healthy model reported a contact pressure of 228 MPa. In the context of wrist extension and displacement, the stroke model (0.68° and 5.54 mm, respectively) reported a lower magnitude than the healthy model (0.98° and 9.43 mm, respectively), which agrees with previously reported works. It was therefore concluded that clinicians should take extra care in rehabilitation treatment of wrist movement in order to prevent the occurrence of other complications. Graphical abstract ᅟ.
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http://dx.doi.org/10.1007/s11517-017-1762-3DOI Listing
July 2018

The Effects of Physiological Biomechanical Loading on Intradiscal Pressure and Annulus Stress in Lumbar Spine: A Finite Element Analysis.

J Healthc Eng 2017 27;2017:9618940. Epub 2017 Aug 27.

Tissue Engineering Group (TEG), National Orthopaedic Centre of Excellence in Research and Learning (NOCERAL), Department of Orthopaedic Surgery, Faculty of Medicine, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia.

The present study was conducted to examine the effects of body weight on intradiscal pressure (IDP) and annulus stress of intervertebral discs at lumbar spine. Three-dimensional finite element model of osseoligamentous lumbar spine was developed subjected to follower load of 500 N, 800 N, and 1200 N which represent the loads for individuals who are normal and overweight with the pure moments at 7.5 Nm in flexion and extension motions. It was observed that the maximum IDP was 1.26 MPa at L1-L2 vertebral segment. However, the highest increment of IDP was found at L4-L5 segment where the IDP was increased to 30% in flexion and it was more severe at extension motion reaching to 80%. Furthermore, the maximum annulus stress also occurred at the L1-L2 segment with 3.9 MPa in extension motion. However, the highest increment was also found at L4-L5 where the annulus stress increased to 17% in extension motion. Based on these results, the increase of physiological loading could be an important factor to the increment of intradiscal pressure and annulus fibrosis stress at all intervertebral discs at the lumbar spine which may lead to early intervertebral disc damage.
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http://dx.doi.org/10.1155/2017/9618940DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5592017PMC
July 2019

New Device for Intrinsic Hand Muscle Strength Measurement: An Alternative to Strain Gauge Handheld Dynamometer.

Eval Health Prof 2019 03 4;42(1):103-113. Epub 2017 Sep 4.

Medical Devices and Technology Group (MEDITEG), Universiti Teknologi Malaysia (UTM), Johor, Malaysia.

An accurate measurement of intrinsic hand muscle strength (IHMS) is required by clinicians for effective clinical decision-making, diagnosis of certain diseases, and evaluation of the outcome of treatment. In practice, the clinicians use Intrins-o-meter and Rotterdam Intrinsic Hand Myometer for IHMS measurement. These are quite bulky, expensive, and possess poor interobserver reliability (37-52%) and sensitivity. The purpose of this study was to develop an alternative lightweight, accurate, cost-effective force measurement device with a simple electronic circuit and test its suitability for IHMS measurement. The device was constructed with ketjenblack/deproteinized natural rubber sensor, 1-MΩ potential divider, and Arduino Uno through the custom-written software. Then, the device was calibrated and tested for accuracy and repeatability within the force range of finger muscles (100 N). The 95% limit of agreement in accuracy from -1.95 N to 2.06 N for 10 to 100 N applied load and repeatability coefficient of ±1.91 N or 6.2% was achieved. Furthermore, the expenditure for the device construction was around US$ 53. For a practical demonstration, the device was tested among 16 participants for isometric strength measurement of the ulnar abductor and dorsal interossei. The results revealed that the performance of the device was suitable for IHMS measurement.
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http://dx.doi.org/10.1177/0163278717727568DOI Listing
March 2019

Fabrication, characterization and application of laccase-nylon 6,6/Fe composite nanofibrous membrane for 3,3'-dimethoxybenzidine detoxification.

Bioprocess Biosyst Eng 2017 Feb 18;40(2):191-200. Epub 2016 Oct 18.

Centre for Sustainable Environment and Water Security (IPASA), Universiti Teknologi Malaysia (UTM), 81310, Johor Bahru, Malaysia.

In this study, laccase was immobilized on nylon 6,6/Fe composite (NFC) nanofibrous membrane and used for the detoxification of 3,3'-dimethoxybenzidine (DMOB). The average size and tensile strength of the NFC membrane were found to be 60-80 nm (diameter) and 2.70 MPa, respectively. The FTIR results confirm that the amine (N-H) group of laccase was attached with Fe particles and the carbonyl (C=O) group of NFC membrane via hydrogen bonding. The half-life of the laccase-NFC membrane storage stability was increased from 6 to 11 weeks and the reusability was significantly extended up to 43 cycles against ABTS oxidation. Enhanced electro-oxidation of DMOB by laccase was observed at 0.33 V and the catalytic current was found to be 30 µA. The DMOB-treated mouse fibroblast 3T3-L1 preadipocytes showed maximum (97 %) cell inhibition at 75 µM L within 24 h. The cytotoxicity of DMOB was significantly decreased to 78 % after laccase treatment. This study suggests that laccase-NFC membrane might be a good candidate for emerging pollutant detoxification.
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http://dx.doi.org/10.1007/s00449-016-1686-6DOI Listing
February 2017

Number of pegs influence focal stress distributions and micromotion in glenoid implants: a finite element study.

Med Biol Eng Comput 2017 Mar 2;55(3):439-447. Epub 2016 Jun 2.

Sport Innovation and Technology Centre (SITC), Institute of Human Centered Engineering (IHCE), Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia.

The present study was conducted to compare the stability of four commercially available implants by investigating the focal stress distributions and relative micromotion using finite element analysis. Variations in the numbers of pegs between the implant designs were tested. A load of 750 N was applied at three different glenoid positions (SA: superior-anterior; SP: superior-posterior; C: central) to mimic off-center and central loadings during activities of daily living. Focal stress distributions and relative micromotion were measured using Marc Mentat software. The results demonstrated that by increasing the number of pegs from two to five, the total focal stress volumes exceeding 5 MPa, reflecting the stress critical volume (SCV) as the threshold for occurrence of cement microfractures, decreased from 8.41 to 5.21 % in the SA position and from 9.59 to 6.69 % in the SP position. However, in the C position, this change in peg number increased the SCV from 1.37 to 5.86 %. Meanwhile, micromotion appeared to remain within 19-25 µm irrespective of the number of pegs used. In conclusion, four-peg glenoid implants provide the best configuration because they had lower SCV values compared with lesser-peg implants, preserved more bone stock, and reduced PMMA cement usage compared with five-peg implants.
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http://dx.doi.org/10.1007/s11517-016-1525-6DOI Listing
March 2017
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