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https://www.readbyqxmd.com/read/28241332/osteopathic-manipulative-treatment-in-the-management-of-isaacs-syndrome
#1
Lisa K T Shanahan, Selena G M Raines, Rachel L Coggins, Teanna Moore, Michael Carnes, Laura Griffin
Isaacs syndrome is a rare neuromuscular disorder characterized by chronic muscle stiffness, cramping, fasciculations, myokymia, and hyperhidrosis. Pathogenesis includes autoimmunity, paraneoplastic disorders, genetic predisposition, or toxin exposure. There is no known cure for Isaacs syndrome. This case report describes a patient who had been given the diagnosis of Isaacs syndrome and received osteopathic manipulative treatment to manage fascial and cranial dysfunctions and reduce nervous system hyperexcitability...
March 1, 2017: Journal of the American Osteopathic Association
https://www.readbyqxmd.com/read/28241206/remote-determination-of-stiffness-of-scaffolds-during-surface-degradation-by-geometric-parameter-measurement-with-time-via-synchrotron-radiation-imaging
#2
Nahshon K Bawolin, Daniel X B Chen
Surface-degrading polymers have been widely used to fabricate scaffolds with the mechanical properties required for tissue regeneration/repair. During their surface degradation, the material properties of polymers remain approximately unchanged, but the scaffold geometry and thus mechanical properties vary with time. This paper presents a novel method to determine the time-dependent mechanical properties, particularly the stiffness, of scaffolds from the geometric changes measured by synchrotron radiation imaging, with the help of finite element analysis...
February 23, 2017: Journal of Biomechanical Engineering
https://www.readbyqxmd.com/read/28241140/enzymatic-mineralization-generates-ultrastiff-and-tough-hydrogels-with-tunable-mechanics
#3
Nicolas Rauner, Monika Meuris, Mirjana Zoric, Joerg C Tiller
The cartilage and skin of animals, which are made up of more than fifty per cent water, are rather stiff (having elastic moduli of up to 100 megapascals) as well as tough and hard to break (with fracture energies of up to 9,000 joules per square metre). Such features make these biological materials mechanically superior to existing synthetic hydrogels. Lately, progress has been made in synthesizing tough hydrogels, with double-network hydrogels achieving the toughness of skin and inorganic-organic composites showing even better performance...
March 1, 2017: Nature
https://www.readbyqxmd.com/read/28241082/modeling-of-the-axon-membrane-skeleton-structure-and-implications-for-its-mechanical-properties
#4
Yihao Zhang, Krithika Abiraman, He Li, David M Pierce, Anastasios V Tzingounis, George Lykotrafitis
Super-resolution microscopy recently revealed that, unlike the soma and dendrites, the axon membrane skeleton is structured as a series of actin rings connected by spectrin filaments that are held under tension. Currently, the structure-function relationship of the axonal structure is unclear. Here, we used atomic force microscopy (AFM) to show that the stiffness of the axon plasma membrane is significantly higher than the stiffnesses of dendrites and somas. To examine whether the structure of the axon plasma membrane determines its overall stiffness, we introduced a coarse-grain molecular dynamics model of the axon membrane skeleton that reproduces the structure identified by super-resolution microscopy...
February 27, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28240903/flexible-bionanocomposites-from-epoxidised-hemp-seed-oil-thermosetting-resin-reinforced-with-halloysite-nanotubes
#5
Peter S Shuttleworth, Ana Maria Díez-Pascual, Carlos Marco, Gary Ellis
Hempseed (Cannabis sativa L.) oil comprises a variety of beneficial unsaturated triglycerides with well-documented nutritional and health benefits. However, it can become rancid over a relatively short time period leading to increased industrial costs and waste of a valuable product. The development of sustainable polymers is presented as a strategy where both the presence of unsaturation and perox-ide content could be affectively utilised to alleviate both this waste and financial burden. After reaction with peroxyacetic acid, incorporation of halloysite nanotubes (HNTs) and sub-sequent thermal curing, without the need for organic sol-vents or interfacial modifiers, flexible transparent materials with a low glass transition temperature were developed...
February 27, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28240883/a-general-bio-inspired-metals-based-synergic-cross-linking-strategy-toward-mechanically-enhanced-materials
#6
Ke Chen, Jin Ding, Shuhao Zhang, Xuke Tang, Yonghai Yue, Lin Guo
Creating lightweight engineering materials combining high strength and great toughness remains a significant challenge. Despite possessing enhanced strength and stiffness, bio-inspired/polymeric materials usually suffer from clearly reduced extensibility and toughness when compared to corresponding bulk polymer materials. Herein, inspired by tiny amounts of various inorganic impurities for mechanical improvement in natural materials, we present a versatile and effective metal ion (Mn+)-based synergic cross-linking (MSC) strategy incorporating eight types of metal ions into material bulks that can drastically enhance the tensile strength (~24...
February 27, 2017: ACS Nano
https://www.readbyqxmd.com/read/28240797/do-histopathological-features-and-microcalcification-affect-the-elasticity-of-breast-cancer
#7
Gamze Durhan, Pelin Seher Öztekin, Hatice Ünverdi, Tülin Değirmenci, Abdullah Durhan, Jale Karakaya, Pınar Nercis Koşar, Enver Necip Köseoğlu, Sema Hücümenoğlu
OBJECTIVES: The aim of this study was to evaluate any association between histological grade, molecular subtypes of breast cancer, and strain elastography, and to investigate whether microcalcification affects the stiffness of tumor in breast cancers with the same histological grade. METHODS: Between April 2015 and March 2016, 94 lesions of 94 patients with the diagnosis of invasive ductal carcinoma were included in the study. Strain elastography was performed on all patients before biopsy...
February 27, 2017: Journal of Ultrasound in Medicine: Official Journal of the American Institute of Ultrasound in Medicine
https://www.readbyqxmd.com/read/28240709/changes-in-vertical-and-joint-stiffness-in-runners-with-advancing-age
#8
Douglas W Powell, D S Blaise Williams
BACKGROUND: Age-related changes in the neuromuscular system underlie reduced performance and injury, but may be mitigated through regular physical activity. It was hypothesized that older (OLD) compared to young (YOUNG) adults would exhibit greater vertical and joint stiffness when running at 3.35 m/s. METHODS: Nine YOUNG and ten OLD runners performed over ground running trials while three-dimensional biomechanics were recorded. Ankle and knee joint angles, moments and stiffness values were compared between YOUNG & OLD...
February 23, 2017: Journal of Strength and Conditioning Research
https://www.readbyqxmd.com/read/28240677/an-unusual-cause-of-myelopathy-ochronotic-spondyloarthropathy-with-positive-hla-b27
#9
Sinem Bozkurt, Lale Aktekin, Fatma Gülçin Uğurlu, Serdar Balci, Nebahat Sezer, Selami Akkus
Ochronosis is a late developing complication of alkaptonuria, a black brownish pigment in the fibrous and cartilaginous tissues. Although most previous studies reported alkaptonuria and back pain due to ochronosis, thoracic myelopathy is an extremely rare complication. In this report, a paraparetic patient who has ochronotic spondiloarthropathy with the presence of HLA B27 antigen is described. He had low back and leg pain and morning stiffness for 5 yrs. Last year, these were followed by tingling, numbness, and weakness the in lower extremities and he was operated on with preliminary diagnosis of prolapsed disc herniation and cord compression...
February 24, 2017: American Journal of Physical Medicine & Rehabilitation
https://www.readbyqxmd.com/read/28240653/paraspinal-muscle-passive-stiffness-remodels-in-direct-response-to-spine-stiffness-a-study-using-the-ent1-deficient-mouse
#10
Kelsey Y Gsell, Derek P Zwambag, Dale E Fournier, Cheryle A Séguin, Stephen H M Brown
STUDY DESIGN: Basic science study of the relationship between the structural properties of the spine and its surrounding musculature. OBJECTIVE: To determine if an increase in spine stiffness causes an inverse compensatory change in the passive stiffness of the adjacent paraspinal muscles. SUMMARY OF BACKGROUND DATA: Intervertebral disc degeneration causes an increase in multifidus passive stiffness; this was hypothesized to compensate for a decrease in spine stiffness associated with disc degeneration...
February 24, 2017: Spine
https://www.readbyqxmd.com/read/28240587/evaluation-of-whether-extremely-high-enthesitis-or-bath-ankylosing-spondylitis-disease-activity-index-basdai-scores-suggest-fibromyalgia-and-confound-the-anti-tnf-response-in-early-non-radiographic-axial-spondyloarthritis
#11
Maxime Dougados, Isabelle Logeart, Annette Szumski, Javier Coindreau, Heather Jones
OBJECTIVES: Differentiating between pain from spondyloarthritis (SpA) and pain from fibromyalgia is challenging. We evaluated patients with non-radiographic axial SpA (nr-axSpA) to determine the percentage of patients with extremely high enthesitis and/or Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) scores, the relationship between extreme scores and depression, and the effect of extreme scores on treatment outcomes with etanercept. METHODS: Patients with nr-axSpA received double-blind etanercept 50 mg or placebo weekly and were divided into those who did vs did not have extreme scores at baseline...
February 23, 2017: Clinical and Experimental Rheumatology
https://www.readbyqxmd.com/read/28240532/facile-assembly-of-aligned-magnetic-nanoparticle-chains-in-polymer-nanocomposite-films-by-magnetic-flow-coating
#12
Hongyi Yuan, Irina J Zvonkina, Abdullah M Al-Enizi, Ahmed A Elzatahry, Jeffrey Pyun, Alamgir Karim
Magnetic nanoparticle chains are found in biosystems such as in the brain of migratory birds. Inspired by such natural assemblies, in a novel approach, the facile assembly of magnetically aligned polymer grafted cobalt nanoparticle (MPGNP) chains in thin polymer films was accomplished by using low strength permanent magnets directly during the flow-casting process. Unlike previous studies of MPGNP chain alignment in the high viscosity melt phase, the high mobility of such dispersed MPGNP during casting polystyrene (PS) film matrix in solution state allowed for formation of well-aligned MPGNP chains at the PS film/air interface...
February 27, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28240417/engineering-photocrosslinkable-bicomponent-hydrogel-constructs-for-creating-3d-vascularized-bone
#13
Mehdi Kazemzadeh-Narbat, Jeroen Rouwkema, Nasim Annabi, Hao Cheng, Masoumeh Ghaderi, Byung-Hyun Cha, Mansi Aparnathi, Akbar Khalilpour, Batzaya Byambaa, Esmaiel Jabbari, Ali Tamayol, Ali Khademhosseini
Engineering bone tissue requires the generation of a highly organized vasculature. Cellular behavior is affected by the respective niche. Directing cellular behavior and differentiation for creating mineralized regions surrounded by vasculature can be achieved by controlling the pattern of osteogenic and angiogenic niches. This manuscript reports on engineering vascularized bone tissues by incorporating osteogenic and angiogenic cell-laden niches in a photocrosslinkable hydrogel construct. Two-step photolithography process is used to control the stiffness of the hydrogel and distribution of cells in the patterned hydrogel...
February 27, 2017: Advanced Healthcare Materials
https://www.readbyqxmd.com/read/28240380/a-novel-in-silico-method-to-quantify-primary-stability-of-screws-in-trabecular-bone
#14
Juri A Steiner, Patrik Christen, Remo Affentranger, Stephen J Ferguson, G Harry van Lenthe
Insufficient primary stability of screws in bone leads to screw loosening and failure. Unlike conventional continuum finite-element models, micro-CT based finite-element analysis (micro-FE) is capable of capturing the patient-specific bone micro-architecture, providing accurate estimates of bone stiffness. However, such in silico models for screws in bone highly overestimate the apparent stiffness. We hypothesized that a more accurate prediction of primary implant stability of screws in bone is possible by considering insertion-related bone damage...
February 27, 2017: Journal of Orthopaedic Research: Official Publication of the Orthopaedic Research Society
https://www.readbyqxmd.com/read/28240373/the-effect-of-simulated-metastatic-lesions-on-the-biomechanical-behavior-of-the-proximal-femur
#15
Emir Benca, Andreas Reisinger, Janina M Patsch, Lena Hirtler, Alexander Synek, Sandra Stenicka, Reinhard Windhager, Winfried Mayr, Dieter H Pahr
Pathologic fractures of femora in patients with metastatic cancer are associated with high morbidity and mortality. Prediction of impending fractures is based on unspecific clinical criteria or past clinician's experience, which leads to underestimation or overtreatment. The aim of this study was to investigate the effect of the site of metastatic lesions on biomechanical behavior of the proximal femur. Sixteen pairs of human femora were scanned with quantitative computed tomography (QCT) to asses bone mineral density...
February 27, 2017: Journal of Orthopaedic Research: Official Publication of the Orthopaedic Research Society
https://www.readbyqxmd.com/read/28240239/hybrid-acoustic-metamaterial-as-super-absorber-for-broadband-low-frequency-sound
#16
Yufan Tang, Shuwei Ren, Han Meng, Fengxian Xin, Lixi Huang, Tianning Chen, Chuanzeng Zhang, Tian Jain Lu
A hybrid acoustic metamaterial is proposed as a new class of sound absorber, which exhibits superior broadband low-frequency sound absorption as well as excellent mechanical stiffness/strength. Based on the honeycomb-corrugation hybrid core (H-C hybrid core), we introduce perforations on both top facesheet and corrugation, forming perforated honeycomb-corrugation hybrid (PHCH) to gain super broadband low-frequency sound absorption. Applying the theory of micro-perforated panel (MPP), we establish a theoretical method to calculate the sound absorption coefficient of this new kind of metamaterial...
February 27, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28239827/quantitative-difference-of-acute-intraoperative-expansion-in-various-body-regions
#17
E Raposio, N Bertozzi
OBJECTIVE: To investigate the efficacy of intraoperative sustained limited expansion (ISLE) by examining the ex vivo biomechanical properties of acutely expanded skin flaps. MATERIALS AND METHODS: Fourteen fresh male cadavers were tested. On both sides of each cadaver, a 4 × 10 cm, the laterally based flap was raised at the external auditory canal of the scalp and a 15 × 8 cm, the proximately based flap was raised at the lateral arm, anterior thorax, and lateral thigh...
February 2017: European Review for Medical and Pharmacological Sciences
https://www.readbyqxmd.com/read/28239715/clustering-in-vibrated-monolayers-of-granular-rods
#18
M González-Pinto, F Borondo, Y Martínez-Ratón, E Velasco
We investigate the ordering properties of vertically-vibrated monolayers of granular cylinders in a circular container at high packing fraction. In line with previous works by other groups, we identify liquid-crystalline ordering behaviour similar to that of two-dimensional hard rectangular particles subject to thermal equilibrium fluctuations. However, due to dissipation, there is a much stronger tendency for particles to cluster into parallel arrangements in the granular system. These clusters behave as a polydisperse mixture of long life-time 'superparticles', and some aspects of the system behaviour can be understood by applying mean-field theories for equilibrium hard rectangles, based on two-body correlations, to these 'superparticles'...
February 27, 2017: Soft Matter
https://www.readbyqxmd.com/read/28239053/transforming-growth-factor-beta-and-forkhead-box-o-transcription-factors-as-cardiac-fibroblast-regulators
#19
Ignacio Norambuena-Soto, Constanza Núñez-Soto, Fernanda Sanhueza-Olivares, Nicole Cancino-Arenas, David Mondaca-Ruff, Raul Vivar, Guillermo Díaz-Araya, Rosemarie Mellado, Mario Chiong
Fibroblasts play several homeostatic roles, including electrical coupling, paracrine signaling and tissue repair after injury. Fibroblasts have low secretory activity. However, in response to injury, they differentiate to myofibroblasts. These cells have an increased extracellular matrix synthesis and secretion, including collagen fibers, providing stiffness to the tissue. In pathological conditions myofibroblasts became resistant to apoptosis, remaining in the tissue, causing excessive extracellular matrix secretion and deposition, which contributes to the progressive tissue remodeling...
February 24, 2017: Bioscience Trends
https://www.readbyqxmd.com/read/28238424/a-transversely-isotropic-coupled-hyperelastic-model-for-the-mechanical-behavior-of-tendons
#20
Thiago André Carniel, Eduardo Alberto Fancello
Several constitutive models for fibrous soft tissues used in literature provide a completely isotropic response when fibers are compressed. However, recent experimental investigations confirm the expectation that tendons behave anisotropically during compression tests. Motivated by these facts, the present manuscript presents an appropriate choice of hyperelastic potentials able to predict the coupled mechanical behaviors of tendons under both tensile and compressive loads with a relatively small number of material parameters...
February 9, 2017: Journal of Biomechanics
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