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Beta-sheet containment by flanking prolines: molecular dynamic simulations of the inhibition of beta-sheet elongation by proline residues in human prion protein

Shamsir MS, Dalby AR

Biophys J, 2007 Mar 15;92(6):2080-9.
PMID: 17172295

Previous molecular dynamic simulations have reported elongation of the existing beta-sheet in prion proteins. Detailed examination has shown that these elongations do not extend beyond the proline residues flanking these beta-sheets. In addition, proline has also been suggested to possess a possible structural role in preserving protein interaction sites by preventing invasion of neighboring secondary structures. In this work, we have studied the possible structural role of the flanking proline residues by simulating mutant structures with alternate substitution of the proline residues with valine. Simulations showed a directional inhibition of elongation, with the elongation progressing in the direction of valine including evident inhibition of elongation by existing proline residues. This suggests that the flanking proline residues in prion proteins may have a containment role and would confine the beta-sheet within a specific length.

Matched MeSH terms: Motion
Infrared tomography: data distribution system and software development for real-time velocity measurement

Abdul Rahim R, Pang JF, Chan KS, Leong LC, Sulaiman S, Abdul Manaf MS

ISA Trans, 2007 Apr;46(2):131-45.
PMID: 17367791

The data distribution system of this project is divided into two types, which are a Two-PC Image Reconstruction System and a Two-PC Velocity Measurement System. Each data distribution system is investigated to see whether the results' refreshing rate of the corresponding measurement can be greater than the rate obtained by using a single computer in the same measurement system for each application. Each system has its own flow control protocol for controlling how data is distributed within the system in order to speed up the data processing time. This can be done if two PCs work in parallel. The challenge of this project is to define the data flow process and critical timing during data packaging, transferring and extracting in between PCs. If a single computer is used as a data processing unit, a longer time is needed to produce a measurement result. This insufficient real-time result will cause problems in a feedback control process when applying the system in industrial plants. To increase the refreshing rate of the measurement result, an investigation on a data distribution system is performed to replace the existing data processing unit.

Matched MeSH terms: Motion
Fulltext Five Year Follow-up of One Stage Bilateral Total Hip Arthroplasty

Tai, C.C., Abbas, A.A., Varaprasad, M., Choon, S.K.

Malays Orthop J, 2007;1(1):22-25.
MyJurnal

We report on the medium term outcome of five patients (ten hips) who underwent one stage bilateral total hip arthroplasty. Both Harris Hip Scores and Oxford Hip Scores improved postoperatively as did range of motion. There was no radiographic evidence of loosening in any hip arthroplasty involved in this study, however one revision surgery was needed due to periprosthetic fracture. There were no increased medical complications. Based on our limited experience, we believe that one stage bilateral total hip arthroplasty is safe in selected patients.

Matched MeSH terms: Range of Motion, Articular
Fulltext Anterior Displacement of Ulnar Nerve at the Elbow inChildren Based on Ultrasonography

Shamsul, H., Saw, A., John, G.

Malays Orthop J, 2007;1(1):29-33.
MyJurnal

This study involved evaluation of the elbows of 50 children between 4 to 14 years of age. Clinical examination for elbow flexion, extension, range of motion and carrying angle were performed, followed by ultrasonographic examination to determine position of the ulnar nerve in relation to the medial epicondyle upon elbow flexion and extension. Thirty-one elbows showed anterior displacement of the ulnar nerve, of which 14 were due to subluxation and 17 to dislocation. We found that anterior translation of ulnar nerve is present in the elbows up to 31% of children, especially those with increased range of elbow motion.

Matched MeSH terms: Range of Motion, Articular
Fulltext Stability of Marangoni convection in superposed fluid and porous layers

Arifin, N.M., Mokhtar, N.F.M., Nazar, R., Pop, I.

ASM Science Journal, 2007;1(1):57-62.
MyJurnal

Linear stability analysis was used to investigate the onset of Marangoni convection in a two-layer system. The system comprised a saturated porous layer over which was a layer of the same fluid. The fluid was heated from below and the upper free surface was deformable. At the interface between the fluid and the porous layer, the Beavers-Joseph slip condition was used and in the porous medium the Darcy law was employed to describe the flow. Predictions for the onset of convection were obtained from the analysis by the perturbation technique. The effect of surface deformation and depth ratio, z (which is equal to the depth of the fluid layer/depth of the porous layer) on the onset of fluid motion was studied in detail.

Matched MeSH terms: Motion
Fulltext Global colour scale for tmeline events in ion dynamics

Sharif, J.M., Latiff, M.S.A., Ngadi, M.A.

ASM Science Journal, 2007;1(2):109-128.
MyJurnal

Spatio-temporal datasets are a collection of datasets where data can vary in both space and time. Theoretically, such datasets can be considered as continuous and discrete. For example, specification of the function, F: Ed  T Rn, where Ed denotes d-dimensional Euclidean space, T = R* ∩ {} the domain of time and Rn an n-dimensional scalar field. Examples of such data sets include time-varying simulation results, film and videos, time-varying medical datasets, geometry models with motion or deformation, meteorological measurements, and many more. It is therefore highly desirable to use visualisation to summarize meaningful information in higher dimensional spatio-temporal datasets. Our aim is to conceive an efficient visual study to facilitate scientists in identifying temporal association among complex and chaotic atom movements in ion trajectories. An application that uses a streamline for spatial motion of ion trajectories and Colour Number Coding Scheme for temporal encoding of high degree of timeline events among mobile ions is proposed. With an anthology of the visual examples, it was revealed that this application would be beneficial for scientists to visually mine any 3D spatio-temporal dataset.

Matched MeSH terms: Motion
Midterm outcome of the Duracon total knee arthroplasty

Yong CK, Choon DS, Soon HC

J Orthop Surg (Hong Kong), 2008 Aug;16(2):197-200.
PMID: 18725672

To present midterm results of Duracon total knee arthroplasty (TKA) performed between 1991 and 2001.

Matched MeSH terms: Range of Motion, Articular
Fulltext Reconstruction of severe patellar infera syndrome with free vascularised composite tensor fascia lata flap

Sulaiman AR, Halim AS, Azman WS, Eskandar H

Singapore Med J, 2008 Aug;49(8):e205-7.
PMID: 18756334

Post-traumatic severe patella infera and intra-articular adhesion may lead to a severe knee stiffness. We report a 29-year-old man, a muslim prayer leader, who had a previous knee injury. He presented with knee movement from ten degrees to 30 degrees, patellar infera with a length of patella to length of patellar tendon ratio of 2:5, and severe knee arthrofibrosis. He underwent incision of the patella ligament and open arthrofibrosis release, leaving a tendon gap and skin defect of 5 cm. Reconstruction was successfully done using a free vascularised composite tensor fascia lata flap. He regained full range of knee motion with normal strength quadriceps mechanism at five months after surgery, and remained in full function at 18 months follow-up.

Matched MeSH terms: Range of Motion, Articular
Fulltext From ultrasound images to block based region motion estimation

Ranjit S, Sim K, Besar R, Tso C

Biomed Imaging Interv J, 2009 Jul;5(3):e32.
PMID: 21611059 MyJurnal DOI: 10.2349/biij.5.3.e32

By applying a hexagon-diamond search (HDS) method to an ultrasound image, the path of an object is able to be monitored by extracting images into macro-blocks, thereby achieving image redundancy is reduced from one frame to another, and also ascertaining the motion vector within the parameters searched. The HDS algorithm uses six search points to form the six sides of the hexagon pattern, a centre point, and a further four search points to create diamond pattern within the hexagon that clarifies the focus of the subject area.

Matched MeSH terms: Motion
The application of empirical mode decomposition for the enhancement of cardiotocograph signals

Krupa BN, Mohd Ali MA, Zahedi E

Physiol Meas, 2009 Aug;30(8):729-43.
PMID: 19550027 DOI: 10.1088/0967-3334/30/8/001

Cardiotocograph (CTG) is widely used in everyday clinical practice for fetal surveillance, where it is used to record fetal heart rate (FHR) and uterine activity (UA). These two biosignals can be used for antepartum and intrapartum fetal monitoring and are, in fact, nonlinear and non-stationary. CTG recordings are often corrupted by artifacts such as missing beats in FHR, high-frequency noise in FHR and UA signals. In this paper, an empirical mode decomposition (EMD) method is applied on CTG signals. A recursive algorithm is first utilized to eliminate missing beats. High-frequency noise is reduced using EMD followed by the partial reconstruction (PAR) method, where the noise order is identified by a statistical method. The obtained signal enhancement from the proposed method is validated by comparing the resulting traces with the output obtained by applying classical signal processing methods such as Butterworth low-pass filtering, linear interpolation and a moving average filter on 12 CTG signals. Three obstetricians evaluated all 12 sets of traces and rated the proposed method, on average, 3.8 out of 5 on a scale of 1(lowest) to 5 (highest).

Matched MeSH terms: Motion
Fulltext Palm vitamin E and glucosamine sulphate in the treatment of osteoarthritis of the knee

Haflah NH, Jaarin K, Abdullah S, Omar M

Saudi Med J, 2009 Nov;30(11):1432-8.
PMID: 19882056

OBJECTIVE: To assess the efficacy of oral palm vitamin E in reducing symptoms of patients with osteoarthritis (OA) of the knee compared to oral glucosamine sulphate.
METHODS: This open study was carried out at the Universiti Kebangsaan Malaysia Medical Center, Kuala Lumpur, Malaysia between March 2006 and November 2007. Seventy-nine patients were recruited to receive either 1.5 g oral glucosamine sulphate or 400 mg oral palm vitamin E for 6 months. Symptoms were assessed using the Western Ontario and McMaster Universities (WOMAC) osteoarthritis index and visual analogue scale (VAS).
RESULTS: Sixty-four patients completed the trial (vitamin E n=33, glucosamine sulfate n=31). After 6 months of treatment, both groups showed a significant improvement in WOMAC scale and significant reduction in the VAS score during standing and walking. There was no significant difference in WOMAC scale and VAS score between the 2 groups. Except for mild allergic reaction and abdominal discomfort in one patient, there were no other serious adverse effects reported. Serum malondialdehyde was significantly higher in the glucosamine group compared to palm vitamin E treated group at the end of the study. Serum of vitamin E was significantly higher in the palm vitamin E group compared to glucosamine.
CONCLUSION: The finding of this study suggests that oral palm vitamin E in a dose of 400 mg taken daily has a potential role in reducing symptoms of patients with OA of the knee. It may be just as effective as glucosamine sulphate in reducing the symptoms and free from serious side effects. Further study is required to ascertain the mechanism of action beside its antioxidant effect.

Matched MeSH terms: Range of Motion, Articular/physiology
Fulltext Posterior Slope of the Tibia Plateau in Malaysian Patients Undergoing Total Knee Replacement

Yoga, R., Sivapathasundaram, N., Suresh, C.

Malays Orthop J, 2009;3(1):78-80.
MyJurnal

The posterior slope of the tibial plateau is an important feature to preserve during knee replacement. The correct slope aids in the amount of flexion and determines if the knee will be loose on flexion. This is a study on the posterior tibial plateau slope based on preoperative and postoperative radiographs of 100 consecutive patients who had total knee replacements. The average posterior slope of the tibia plateau was 10.1 degrees. There is a tendency for patients with higher pre-operative posterior tibial plateau slope to have higher post-operative posterior tibial plate slope.

Matched MeSH terms: Range of Motion, Articular
Fulltext Early functional outcome of a modified Brostrom-Gould surgery using bioabsorbable suture anchor for chronic lateral ankle instability

Shahrulazua A, Ariff Sukimin MS, Tengku Muzaffar TM, Yusof MI

Singapore Med J, 2010 Mar;51(3):235-41.
PMID: 20428746

The purpose of this study was to evaluate the early functional outcome following the use of a bioabsorbable suture anchor to simplify the repair of injured lateral ankle structures as a variation of an established technique known as the Brostrom-Gould procedure.

Matched MeSH terms: Range of Motion, Articular
Aesthetic refinements in second toe-to-thumb transfer surgery

Zhao J, Tien HY, Abdullah S, Zhang Z

Plast Reconstr Surg, 2010 Dec;126(6):2052-2059.
PMID: 21124145 DOI: 10.1097/PRS.0b013e3181f44994

BACKGROUND: Second toe-to-thumb transfer is a good alternative to using the great toe for reconstruction of the thumb. It achieves excellent function and reduces morbidity to the donor foot. However, cosmesis is often poor. The second toe has three unattractive features, a narrow "neck," a bulbous tip, and a short nail.
METHODS: The authors describe a modified second toe transfer that addresses cosmesis in six patients. These include (1) harvesting a flap from the adjacent side of the great toe and insetting it into the volar aspect of the second toe to give more bulk, (2) making skin excisions on each side of the tip to reduce the bulbous appearance, and (3) excising the eponychium to produce apparent lengthening of the nail.
RESULTS: The mean follow-up period was 18 months (range, 6 to 36 months). The procedure resulted in good function and improved cosmesis in all six cases. Part of the great toe flap was lost in one case. The mean two-point discrimination in the transferred toes was 10.1 mm, with protective sensation present in the flaps. The range of motion of the transferred toe was 14 to 38 degrees at the metatarsophalangeal joint, 16 to 55 degrees at the proximal interphalangeal joints, and 20 to 36 degrees in the distal interphalangeal joints. All patients except one were happy with the appearance of the transferred toe.
CONCLUSION: This novel approach will allow patients to take advantage of the lower morbidity to the donor site afforded by second toe-to-thumb transfer and provide the patients with a more aesthetic appearance of the new thumb.

Matched MeSH terms: Range of Motion, Articular/physiology
Fulltext Specific heats of neat and glycerol plasticized polyvinyl alcohol

Lee, Tin Sin, Wan Aizan Wan Abdul Rahman, Abdul Razak Rahman, Noor Azian Morad, Mohd Shahrul Nizam Salleh

Pertanika Journal of Science & Technology, 2010;18(2):-.
MyJurnal

The specific heats (Csp) of neat polyvinyl alcohol (NPVOH) and 40 phr glycerol plasticized polyvinyl alcohol (PPVOH) were measured using a method known as power compensate differential scanning calorimetry. A high purity sapphire (Al2O3) was used as a reference material. NPVOH has a melting temperature of approximately 480 K, while PPVOH has a value of 30 K lower than NPVOH. The amplitude increment of Csp for NPVOH was also higher than PPVOH at melting stage. Overall, Csp of NPVOH is lower than PPVOH because glycerol has reduced the rigidity of PVOH and subsequently induced the motion of molecular structure at an elevated temperature. Based on the specific heat outcomes, neat PVOH and glycerol plasticized PVOH required 1173.544 J/g and 1946.631 J/g, respectively, to heat from 330 to 550 K.

Matched MeSH terms: Motion
Fulltext Modelling the effects of sediment on the seismic behaviour of Kinta roller compacted concrete dam

Jaafar, M.S., Thanoon, Waleed A., Mohammed, T.A., Huda, A.M., Noorzaei, J.

Pertanika Journal of Science & Technology, 2010;18(1):-.
MyJurnal

An attempt was made in this investigation to trace the dynamic response of roller compacted concrete dam, which is subjected to horizontal ground motion by considering the interactions between flexible foundations, reservoir water, and bottom reservoir sediments. Two-dimensional finiteinfinite element was used for the non-linear elasto-plastic dynamic analysis. In this analysis, special emphasis was given to the non-linear behaviour of discontinuities along RCC dam-bedding rock foundation which was modelled by thin layer interface. Analysis was first carried out under static loading (self-weight and hydrostatic pressure), and this this was followed by seismic analysis, with hydrodynamic pressure effect in a dam-reservoir system. Based on the numerical dynamic results, it is concluded that the bottom reservoir sediment has significant effect on the seismic response of the RCC gravity dam. Moreover, there is a redistribution of the stresses at thin layer interface with significant stresses reduction, which is resulted from the release of energy through different modes of deformation in this region.

Matched MeSH terms: Motion
Fulltext Modelling and simulation of vibration and Input tracking control of a single-link flexible manipulator

Mohd Ashraf Ahmad, Zaharuddin Mohamed

Pertanika Journal of Science & Technology, 2010;18(1):-.
MyJurnal

This paper presents investigations into the development of control schemes for end-point vibration
suppression and input tracking of a flexible manipulator. A constrained planar single-link flexible manipulator is considered and the dynamic model of the system is derived using the assumed mode method. To study the effectiveness of the controllers, a Linear Quadratic Regulator (LQR) was initially developed for control of rigid body motion. This is then extended to incorporate a noncollocated PID controller and a feedforward controller based on input shaping techniques to control vibration (flexible motion) of the system. For feedforward controller, positive and modified specified negative amplitude (SNA) input shapers are proposed and designed based on the properties of the system. Results from the simulation of the manipulator responses with the controllers are presented in time and frequency domains. The performances of the control schemes are assessed in terms of level of vibration reduction, input tracking capability and time response specifications. Finally, a comparative assessment of the control techniques is presented and discussed.

Matched MeSH terms: Motion
Fulltext Nonunion of Lateral Humeral Condylar Fracture in A Child with Cubitus Varus

Sulaiman, A.R., Munajat, I., Mohd, E.F., Sharifudin, M.A.

Malays Orthop J, 2010;4(3):29-31.
MyJurnal

Patients with cubitus varus deformity secondary to malunited supracondylar fracture are at risk for lateral humeral condylar (LHC) fracture. This report describes a child presenting with preexisting malunion of supracondylar fracture presenting along with nonunion of a LHC fracture following a recent injury. The patient underwent resection osteotomy of the metaphyseal proximal fragment of the fracture surface, reduction of the displaced LHC fragment and screw fixation. This procedure corrected the cubitus varus and treated the nonunion of the lateral condyle thus avoiding a supracondylar osteotomy procedure. Treatment resulted in solid union, good range of motion and no avascular necrosis.

Matched MeSH terms: Range of Motion, Articular
Currents simulation in the Malacca Straits by using three-dimensional numerical model

Rizal S, Setiawan I, Ilhamsyah Y, Musman M, Iskandar T, Wahid MA

Sains Malaysiana, 2010;39.

The Malacca Straits is located between Peninsula Malaysia and Sumatra Island. This investigation used equation of motion (Navier-Stokes equation) with the following driving forces: tides, wind of National Centers for Environmental Prediction (NCEP) for year of 2007, salinity and temperature. The equation of motion was solved by means of Hamburg Shelf Ocean Model (HAMSOM). The results for both southwest and northeast monsoon were explained and discussed. The simulation results both for February and August 2007 were relatively similar. Current surface simulation in the Malacca Straits agrees well with the current pattern of previous works. The magnitude of current was between 10-70 cm/s to the northwest. While at the layer 30-50 m in the Malacca Straits, the currents have the magnitude of 10-30 cm/s towards northwest. For the bottom current, the current speed was 0-20 cm/s towards northwest. For the surface and 30-50 m layer, generally the current magnitudes were greater in February compared to those in August. While for the bottom layer, the current magnitudes between February and August were relatively the same.

Matched MeSH terms: Motion
Articular cartilage regeneration with autologous peripheral blood progenitor cells and hyaluronic acid after arthroscopic subchondral drilling: a report of 5 cases with histology

Saw KY, Anz A, Merican S, Tay YG, Ragavanaidu K, Jee CS, et al.

Arthroscopy, 2011 Apr;27(4):493-506.
PMID: 21334844 DOI: 10.1016/j.arthro.2010.11.054

PURPOSE: The purpose of this study was to evaluate the quality of articular cartilage regeneration after arthroscopic subchondral drilling followed by postoperative intraarticular injections of autologous peripheral blood progenitor cells (PBPCs) in combination with hyaluronic acid (HA).
METHODS: Five patients underwent second-look arthroscopy with chondral core biopsy. These 5 patients are part of a larger pilot study in which 180 patients with International Cartilage Repair Society grade III and IV lesions of the knee joint underwent arthroscopic subchondral drilling followed by postoperative intra-articular injections. Continuous passive motion was used on the operated knee 2 hours per day for 4 weeks. Partial weight bearing was observed for the first 6 to 8 weeks. Autologous PBPCs were harvested 1 week after surgery. One week after surgery, 8 mL of the harvested PBPCs in combination with 2 mL of HA was injected intra-articularly into the operated knee. The remaining PBPCs were divided into vials and cryopreserved. A total of 5 weekly intra-articular injections were given.
RESULTS: Second-look arthroscopy confirmed articular cartilage regeneration, and histologic sections showed features of hyaline cartilage. Apart from the minimal discomfort of PBPC harvesting and localized pain associated with the intra-articular injections, there were no other notable adverse reactions.
CONCLUSIONS: Articular hyaline cartilage regeneration is possible with arthroscopic subchondral drilling followed by postoperative intraarticular injections of autologous PBPCs in combination with HA.
LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Matched MeSH terms: Motion Therapy, Continuous Passive

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