Expression and functional role of formyl peptide receptor in human bone marrow-derived mesenchymal stem cells

AbstractWe investigated the expression of formyl peptide receptor (FPR) and its functional role in human bone marrow-derived mesenchymal stem cells (MSCs). We analyzed the expression of FPR by using ligand-binding assay with radio-labeled N-formyl-met-leu-phe (fMLF), and found that MSCs express FPR. FMLF stimulated intracellular calcium increase, mitogen-activated protein kinases activation, and Akt activation, which were mediated by Gi proteins. MSCs were chemotactically migrated to fMLF. FMLF-induced MSC chemotaxis was also completely inhibited by pertussis toxin, LY294002, and PD98059, indicating the role of Gi proteins, phosphoinositide 3-kinase, and extracellular signal regulated protein kinase. N-terminal fragment of annexin-1, Anx-1(2–26), an endogenous agonist for FPR, also induced chemotactic migration of MSCs. Thus MSCs express functional FPR, suggesting a new (patho)physiological role of FPR and its ligands in regulating MSC trafficking during induction of injured tissue repair

Mean flow characteristics of two-dimensional wings in ground effect

ABSTRACTThe present study numerically investigates the aerodynamic characteristics of two-dimensional wings in the vicinity of the ground by solving two-dimensional steady incompressible Navier-Stokes equations with the turbulence closure model of the realizable k-ε model. Numerical simulations are performed at a wide range of the normalized ground clearance by the chord length (0.1≤h/C ≤ 1.25) for the angles of attack (0° ≤ α ≤ 10°) in the pre-stall regime at a Reynolds number (Re) of 2×106 based on free stream velocity U∞ and the chord length. As the physical model of this study, a cambered airfoil of NACA 4406 has been selected by a performance test for various airfoils. The maximum lift-to-drag ratio is achieved at α = 4° and h/C = 0.1. Under the conditions of α = 4° and h/C = 0.1, the effect of the Reynolds number on the aerodynamic characteristics of NACA 4406 is investigated in the range of 2× 10 5 ≤ Re ≤ 2× 109. As Re increases, Cl and Cd augments and decreases, respectively, and the lift-to-drag ratio increases linearly

Novel implant design of the proximal interphalangeal joint using an optimized rolling contact joint mechanism

Background The aims of this study were to propose a novel implant design for the proximal interphalangeal joint (PIPJ) of the hand using a rolling contact joint (RCJ) mechanism and to derive an optimal implant design based on human PIPJ kinematics. Methods In total, 10 participants with normal PIPJs were enrolled in this study. True lateral finger radiographs were obtained in 10° increments from 0º (full extension) to 120° flexion of PIPJ. Radiographs were used to determine the average center of rotation, which formed the basis of a mathematical expression of the PIPJ kinematics. The variations in extensor tendon excursions in relation to the range of motion of PIPJ were determined using results from previous cadaveric studies. As the next step, a PIPJ implant design using an RCJ mechanism that was most consistent with the mathematically expressed PIPJ kinematics and tendon excursions was determined using a constrained optimization algorithm. Results The final proposed PIPJ implant had a relatively constant center of rotation over the entire PIPJ range of motion among the participants. In addition, the extensor tendon excursions of the proposed implant as applied to the phalangeal bones were similar to those of the human tendon. The proposed PIPJ implant achieved an acceptable position of the RCJ surface on the proximal and middle phalanges, which was derived from the constrained optimization algorithm. Conclusions A novel PIPJ implant design using an RCJ mechanism demonstrated acceptable outcomes in terms of PIPJ human kinematics and tendon excursions.This research was supported by the Seoul National University Bundang Hospital Research Fund (grant no. 14-2017-001) and in part by the convergence technology development program for bionic arm through the National Research Foundation of Korea (NRF) funded by the Ministry of Science & ICT (no. 2015M3C1B2052817). The funders had no role in the study design, data collection, analysis and interpretation, and writing the manuscript

GAIT ASYMMETRY IN CHILDREN WITH DOWN SYNDROME

It has been reported that approximately 80% of children with Down syndrome (OS) exhibit gait problems (Matteo, 2002), characterized by flat-footed contact with no heel-strike, excessive abduction of the leg in the swing phase, and abnormal knee and hip f1exions throughout the gait cycle (Parker et aI., 1986). Due to muscle hypotonia, muscle weakness, !igamentous laXity, and other orthopedic abnormalities, different gait characteristics exist. The purpose of this study was to investigate the gait (walking and running) asymmetry in children with OS

Electric polarization enhancement in multiferroic CoCr2O4 crystals with Cr-site mixing

Single crystals of multiferroic cobalt chromite Co (Cr2-x Cox) O4 have been grown via several methods to have different Co3+ doping levels (x=0.0, 0.14, and 0.18). Under magnetic fields, all the crystals display electric polarization reversal below their spiral spin ordering temperatures. We find that both saturated electric polarization and magnetization under magnetic fields increase significantly with the increase in x. This result can be qualitatively explained by a broken balance between at least two electric polarization contributions existing in CoCr2 O4 and is expected to be useful in tailoring electric polarization in similar kinds of multiferroics. © 2009 American Institute of Physics.open222

THE EFFECT OF 12-WEEK STRENGTH TRAINING ON GAIT CHARACTERISTICS IN ADOLESCENT WITH DOWN SYNDROME: A SINGLE CASE STUDY

It has been reported that approximately 80% of individuals with Down syndrome (DS) exhibit abnormal gait characteristics. They are exhibited by flat-footed contact with no heel-strike, excessive abduction of the leg in the swing phase, and abnormal knee and hip flexion throughout the gait cycle (Matteo, 2002). The purpose of this study was to examine the influence of a 12-week strength training program on the gait characteristics during walking by an adolescent with DS

Bacterial profile of suction drains and the relationship thereof to surgical-site infections in prosthetic breast reconstruction

Background Despite the increasing popularity of prosthetic breast reconstruction, scant data exist on the microbiological profile of drainage fluid from closed-suction drains and the relationship thereof to surgical-site infections (SSIs) in breast reconstruction surgery. This study aimed to determine whether bacteria isolated from drainage fluid were associated with the development of SSIs, and whether the bacterial profile of drainage fluid could be a clinically useful predictor of SSIs. Methods We performed a retrospective chart review of 61 women who underwent tissue expander/implant or direct-to-implant reconstructions. Patient demographics and culture studies of drainage fluid from suction drains collected on postoperative day 7 were evaluated. Results Sixteen patients (26.23%) were culture-positive, and 45 patients (73.77%) were culture-negative. The most frequently isolated bacteria were coagulase-negative staphylococci, followed by Staphylococcus aureus. SSIs were diagnosed in seven patients and were mostly resolved by systemic antibiotics; however, the tissue expander or implant was explanted in two patients. Positive culture of drainage fluid from closed-suction drains was significantly associated with the development of SSIs (P<0.05). The positive predictive value was 37.50%,and the negative predictive value was 97.78%. Conclusions To our knowledge, this study is the first to demonstrate a significant association between the microbiological profile of drainage fluid from closed-suction drains and the development of SSIs in patients with prosthetic breast reconstructions. The high negative predictive value suggests that microbial testing of drainage fluid from closed-suction drains may have clinical utility. Further prospective studies with larger sample sizes are required to confirm our findings

KINEMATIC ANALYSIS OF THE WOMEN’S JAVELIN THROW AT THE IAAF WORLD CHAMPIONSHIPS, DAEGU 2011

The purpose of this study was to analyze the kinematic variables for the women's javelin throw at the IAAF World Championships, Daegu 2011. Three-dimensional motion analyses of the eight players who qualified for the final round were carried out to obtain the data. The results showed that average release, attitude, and attack angles were 38.0±2.0°, 40.4±4.3°, and 3.7±1.1°, respectively. At the release, the average inclination angle of the trunk, upper arm, forearm were 60.8±8.3°, 47.3±10.1°, and 62.6±10.6°, respectively. Moreover, the release velocity and the release height results averaged 25.60±1.16 m/s and 1.86±0.05 m. The crossover phase and delivery phase had average distances of 1.88±0.31 m and 1.53±0.21 m. After release, the average distance between the landing foot and the foul line was 1.72±0.63 m

Algorithm for the management of ectropion through medial and lateral canthopexy

Background Patients with ectropion experience devastating symptoms. Therefore, the preventionand management of this condition are of utmost importance. To treat ectropion, it is important to perform medial and lateral canthopexy in an effective way. In this study, we propose a comprehensive algorithm for the prevention and management of ectropion based on a new classification of ectropion according to its signs and causes. Methods Canthopexy was performed in 68 cases according to the proposed algorithm, which starts with a categorization of the types of ectropion and ends with the recommended operative technique. To assess the results, we reviewed clinical preoperative and postoperative photographs. To evaluate improvements in patients’ symptoms, we conducted a survey with responses scored on a Likert scale. Results None of the patients had scleral show postoperatively. The average patient satisfaction score was satisfied or higher for all symptoms, and the most improved symptom was aesthetic appearance. No major complications were reported. Conclusions For the comprehensive management of ectropion, it is crucial to consider both treatment and prevention. Through the simple surgical algorithm proposed in this study, both medically acceptable results and high levels of patient satisfaction were achieved without significant postoperative complications. We recommend using this algorithm for the comprehensive management of ectropion