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https://www.readbyqxmd.com/read/28524376/fluorinated-peg-polypeptide-polyplex-micelles-have-good-serum-resistance-and-low-cytotoxicity-for-gene-delivery
#1
Ting Wu, Longhai Wang, Shenggang Ding, Yezi You
A novel PEGylation polypeptide, poly(ethylene glycol)-b-poly(l-lysine)-b-poly(l-cysteine) (PEG-PLL-PCys) triblock copolymer is synthesized via the sequential ring-opening polymerization of amino acid N-carboxyanhydrides initiated by methoxypolyethylene glycol amine (mPEG-NH2 , Mw is 2 kDa). Subsequently, the obtained polypeptide is partially conjugated with fluorocarbon chains via disulfide exchange reaction. PLL segment can condense plasmid DNA through an electrostatic force to form a complex core, PEG segment surrounding the complex like a corona can prevent the complex from precipitation and reduce the adsorption of serum, while PCys segment with fluorocarbon can enhance the cellular uptake and the stability of the formed polyplex micelles in physiological conditions...
May 19, 2017: Macromolecular Bioscience
https://www.readbyqxmd.com/read/28499865/implication-of-altered-autonomic-control-for-orthostatic-tolerance-in-sci
#2
REVIEW
Jill Maria Wecht, William A Bauman
Neural output from the sympathetic and parasympathetic branches of the autonomic nervous system (ANS) are integrated to appropriately control cardiovascular responses during routine activities of daily living including orthostatic positioning. Sympathetic control of the upper extremity vasculature and the heart arises from the thoracic cord between T1 and T5, whereas splanchnic bed and lower extremity vasculature receive sympathetic neural input from the lower cord between segments T5 and L2. Although the vasculature is not directly innervated by the parasympathetic nervous system, the SA node is innervated by post-ganglionic vagal nerve fibers via cranial nerve X...
May 3, 2017: Autonomic Neuroscience: Basic & Clinical
https://www.readbyqxmd.com/read/28495542/endothelial-function-is-preserved-in-veins-harvested-by-either-endoscopic-or-surgical-techniques
#3
Adam R Wheeler, Daniel E Kendrick, Matt T Allemang, Andre F Gosling, Ann H Kim, Alfred Hausladen, Vikram S Kashyap
OBJECTIVES: Endoscopic vein harvest for lower extremity arterial bypass grafting has been questioned due to concern for endothelial damage during procurement. We sought to compare Nitric Oxide (NO)-mediated endothelial dependent relaxation (EDR) in vein segments harvested using open surgical (OH) versus endoscopic (EH) techniques. METHODS: Saphenous vein segments were harvested for lower extremity bypass, and a single, minimally handled section of saphenous vein, free of branches, was taken from the end of the graft...
May 8, 2017: Annals of Vascular Surgery
https://www.readbyqxmd.com/read/28485593/structural-studies-of-hydrographenes
#4
Elena Vishnyakova, Gaowei Chen, Bruce E Brinson, Lawrence B Alemany, W Edward Billups
As a result of the unique physical and electrical properties, graphene continues to attract the interest of a large segment of the scientific community. Since graphene does not occur naturally, the ability to exfoliate and isolate individual layers of graphene from graphite is an important and challenging process. The interlayer cohesive energy of graphite that results from van der Waals attractions has been determined experimentally to be 61 meV per carbon atom (61 meV/C atom). This requires the development of a method to overcome the strong attractive forces associated with graphite...
May 9, 2017: Accounts of Chemical Research
https://www.readbyqxmd.com/read/28485078/tubular-open-porous-%C3%AE-tcp-plcl-scaffolds-as-guiding-structure-for-segmental-bone-defect-regeneration-in-a-novel-sheep-model
#5
Anne-Marie Pobloth, Hanna Schell, Ansgar Petersen, Katleen Beierlein, Christian Kleber, Katharina Schmidt-Bleek, Georg N Duda
Large segmental bone defect reconstruction with sufficient functional restoration is one of the most demanding challenges in orthopedic surgery. Available regenerative treatment options, as the vascularized bone graft transfer, the Masquelet technique or the Ilizarov distraction osteogenesis, are associated with specific indications and distinct limitations. As an alternative, a hollow cylindrical ceramic-polymer composite scaffold (beta-tricalcium phosphate and poly-lactid co-ε- caprolactone), facilitating a strong surface guiding effect for tissue ingrowth (group 1; n = 6) was investigated here...
May 8, 2017: Journal of Tissue Engineering and Regenerative Medicine
https://www.readbyqxmd.com/read/28482519/synthesis-of-star-like-hybrid-poss-pdmaema-b-pdla-8-copolymer-and-its-stereocomplex-properties-with-plla
#6
Xiaoshan Fan, Mengya Cao, Xing Zhang, Zibiao Li
Although poly(lactide) (PLA), when used as biomaterials, possesses many good properties, its high hydrophobicity and slow degradation may hinder its applications. In this work, a novel star-like oligomeric silsesquioxane-(poly(2-dimethylaminoethyl methacrylate)-b-poly(d-lactide))8 (POSS-(PDMAEMA-b-PDLA)8) was first synthesized through a three-step procedure that involves Reversible Addition-Fragmentation Chain Transfer (RAFT) polymerization of DMAEMA initiated by the macroinitiator POSS-8-CTA, and then conversion of the trithiocarbonated end groups on PDMAEMA arms into hydroxyl groups by a combination of aminolysis and Michael addition followed by controlled ring-opening polymerization of D-LA...
July 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
https://www.readbyqxmd.com/read/28481832/new-technique-of-femtosecond-laser-assisted-intracorneal-ring-segment-implantation
#7
Luis Izquierdo, Alejandra Orozco, Maria A Henriquez
PURPOSE: To describe a new technique of femtosecond laser-assisted intracorneal ring segment implantation. METHODS: The study included 6 eyes of 5 patients. Software of the LDV Z6 femtosecond laser was modified to create a 110-degree reverse side cut between the corneal surface and incision instead of the conventional 90 degree angle (which changed the angle between the incision and tunnel from conventional 90-70 degrees) and 2 disjointed tunnels separated by 10 degrees arc length at the proximal and distal ends...
May 3, 2017: Cornea
https://www.readbyqxmd.com/read/28476917/optical-coherence-tomography-of-the-kayser-fleischer-ring-an-ancillary-diagnostic-tool-for-wilson-s-disease-in-children
#8
Anubha Rathi, Brijesh Takkar, Nripen Gaur, Prafulla Kumar Maharana
This report presents anterior segment optical coherence tomography (AS-OCT) images of Kayser-Fleischer ring (KFR) in a child. The AS-OCT images highlight differential reflectivity of the KFR depending on amount of copper deposited in cornea, thus supporting the role of AS-OCT as a follow-up tool. Utility of AS-OCT for diagnosing and documenting the KFR in children otherwise uncooperative for detailed slit lamp examination is discussed.
May 5, 2017: BMJ Case Reports
https://www.readbyqxmd.com/read/28472471/successful-immunosuppressant-free-heterotopic-transplantation-of-tracheal-allografts-in-the-pig
#9
Julien De Wolf, Mathias Brieu, Christophe Zawadzki, Alexandre Ung, Eric Kipnis, Ramadan Jashari, Thomas Hubert, Pierre Fayoux, Christophe Mariette, Marie-Christine Copin, Alain Wurtz
OBJECTIVES: It has been demonstrated that both heterotopic and orthotopic transplants of epithelium-denuded cryopreserved tracheal allografts are feasible in immunosuppressant-free rabbits. Validation of these results in large animals is required before considering clinical applications. We evaluated the viability, immune tolerance and strain properties of such tracheal allografts heterotopically transplanted in a pig model. METHODS: Ten tracheal segments, 5 short (5 rings) and 5 long (10 rings), were obtained from male Landrace pigs...
May 2, 2017: European Journal of Cardio-thoracic Surgery
https://www.readbyqxmd.com/read/28456735/aneurysms-of-the-proximal-segment-of-the-anterior-cerebral-artery-a-new-classification-system-with-corresponding-therapeutic-options
#10
Xinmin Ding, Peyton Lubbock Nisson, Whitney S James, Michael T Lawton, Shaohua Ren, Lu Jia, Honging Ji
OBJECTIVE: This study aims to establish a new classification system for proximal anterior cerebral artery (A1) aneurysms and to offer treatment strategies, based on the lessons learned by studying the case reports of 41 patients with A1 aneurysms. METHODS: 2,332 consecutive patients with intracranial aneurysms were treated at a single medical center between June 2005 and May 2015. Forty-one patients with 42 A1 aneurysms were treated by surgical clipping or endovascular coiling...
April 26, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/28455629/validation-of-an-active-shape-model-based-semi-automated-segmentation-algorithm-for-the-analysis-of-thigh-muscle-and-adipose-tissue-cross-sectional-areas
#11
Jana Kemnitz, Felix Eckstein, Adam G Culvenor, Anja Ruhdorfer, Torben Dannhauer, Susanne Ring-Dimitriou, Alexandra M Sänger, Wolfgang Wirth
OBJECTIVE: To validate a semi-automated method for thigh muscle and adipose tissue cross-sectional area (CSA) segmentation from MRI. MATERIALS AND METHODS: An active shape model (ASM) was trained using 113 MRI CSAs from the Osteoarthritis Initiative (OAI) and combined with an active contour model and thresholding-based post-processing steps. This method was applied to 20 other MRIs from the OAI and to baseline and follow-up MRIs from a 12-week lower-limb strengthening or endurance training intervention (n = 35 females)...
April 28, 2017: Magma
https://www.readbyqxmd.com/read/28453367/retinal-pigment-epithelium-photoreceptor-layer-alterations-in-a-patient-with-sturge-weber-syndrome-with-diffuse-choroidal-hemangioma
#12
Solmaz Abdolrahimzadeh, Francesco Parisi, Flavio Mantelli, Andrea Perdicchi, Gianluca Scuderi
PURPOSE: To describe an 8-year-old girl with diagnosis of Sturge-Weber syndrome (SWS) presenting with glaucoma, abnormal iris vessels, diffuse choroidal hemangioma, and small white dot-shaped "microdrusen-like" alterations of the retina in the right eye. PATIENT AND METHODS: Complete ophthalmological examination was performed with slit-lamp anterior segment assessment and fundus ophthalmoscopy. Near infrared reflectance (NIR) and enhanced depth imaging (EDI) spectral domain optical coherence tomography (SD-OCT) were carried out...
April 28, 2017: Ophthalmic Genetics
https://www.readbyqxmd.com/read/28452541/end-point-of-the-ultraspinning-instability-and-violation-of-cosmic-censorship
#13
Pau Figueras, Markus Kunesch, Luis Lehner, Saran Tunyasuvunakool
We determine the end point of the axisymmetric ultraspinning instability of asymptotically flat Myers-Perry black holes in D=6 spacetime dimensions. In the nonlinear regime, this instability gives rise to a sequence of concentric rings connected by segments of black membrane on the rotation plane. The latter become thinner over time, resulting in the formation of a naked singularity in finite asymptotic time and hence a violation of the weak cosmic censorship conjecture in asymptotically flat higher-dimensional spaces...
April 14, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28445464/burgess-shale-fossils-illustrate-the-origin-of-the-mandibulate-body-plan
#14
Cédric Aria, Jean-Bernard Caron
Retracing the evolutionary history of arthropods has been one of the greatest challenges in biology. During the past decade, phylogenetic analyses of morphological and molecular data have coalesced towards the conclusion that Mandibulata, the most diverse and abundant group of animals, is a distinct clade from Chelicerata, in that its members possess post-oral head appendages specialized for food processing, notably the mandible. The origin of the mandibulate body plan, however, which encompasses myriapods, crustaceans and hexapods, has remained poorly documented...
May 4, 2017: Nature
https://www.readbyqxmd.com/read/28444758/intraoperative-use-of-a-transarticular-circular-fixator-construct-to-facilitate-reduction-and-stabilisation-of-a-proximal-tibial-physeal-fracture-in-a-dog
#15
M D Johnson, D D Lewis, M D Winter
CASE REPORT: A 4-month-old female intact American Pit Bull Terrier was presented for right pelvic limb lameness 1 day after the dog had been hit by an all-terrain vehicle. Orthogonal radiographs of the right stifle revealed a Salter-Harris type IV fracture through the proximal tibial physis extending caudodistally through the proximal tibial metaphysis. The distal tibia was markedly displaced cranially, laterally and proximally, resulting in complete overriding of the fracture segments...
May 2017: Australian Veterinary Journal
https://www.readbyqxmd.com/read/28443268/complicated-postoperative-course-after-pulmonary-artery-sling-repair-and-slide-tracheoplasty
#16
Angelika Weber, Birgit Donner, Marie-Hélène Perez, Stefano Di Bernardo, Daniel Trachsel, Kishore Sandu, Nicole Sekarski
Pulmonary artery sling (PAS) is a rare congenital condition in which the left pulmonary artery (LPA) arises from the right pulmonary artery, and then passes between the trachea and the esophagus to reach the left lung, thereby forming a sling around the airway. It is often associated with intrinsic tracheal stenosis due to complete cartilaginous rings. Therapeutic management nowadays consists of one-stage reimplantation of the LPA and tracheoplasty with cardiopulmonary bypass support. Here, we present a 7-week-old boy with PAS and long-segment tracheal stenosis (LSTS) who underwent surgical intervention consisting of reimplantation of the LPA and slide tracheoplasty...
2017: Frontiers in Pediatrics
https://www.readbyqxmd.com/read/28442207/tibio-talo-calcaneal-fusion-after-limb-salvage-procedures-a-retrospective-study
#17
Lukas Zak, Gerald E Wozasek
BACKGROUND: The treatment of limb threatening trauma on the distal tibia or hindfoot often results in posttraumatic osteoarthritis requiring tibiotalocalcaneal (TTC) arthrodesis. The purpose of this study was to present a case series of patients undergoing various techniques of joint fusion after bone reconstruction and deformity correction as a salvage procedure. The study should help trauma surgeons making decisions in limb salvage and deformity correction in complex lower leg and foot injuries by presenting options and treatment strategies...
April 15, 2017: Injury
https://www.readbyqxmd.com/read/28434061/the-sources-of-calcium-for-noradrenaline-induced-contraction-in-the-human-thoracic-internal-artery
#18
Leszek Buzun, Beata Modzelewska, Anna Kostrzewska, Ewa Kleszczewska, Tomasz Kleszczewski
The aim of the present study was to examine the contribution of intracellular and extracellular calcium sources in contraction caused by noradrenaline (NA) of the human internal thoracic artery (ITA) in vitro. Distal segments of ITA were obtained from 20 patients (aged 38-73, at the time of routine coronary artery surgical revascularization (CABG)). Contractile responses to 10(-6) mol/L NA in the physiological salt solution and in Ca(2+)-free solution without and after incubation with 10(-6) mol/L thapsigargin (TSG) were recorded under isometric conditions...
April 22, 2017: Pflügers Archiv: European Journal of Physiology
https://www.readbyqxmd.com/read/28428070/no-production-and-potassium-channels-activation-induced-by-crotalus-durissus-cascavella-underlie-mesenteric-artery-relaxation
#19
S S Santos, R L C Jesus, L O Simões, W P Vasconcelos, I A Medeiros, R C Veras, L L Casais-E-Silva, D F Silva
Animal toxins are natural resources for pharmacological studies. The venom of Crotalus durissus cascavella (C.d. cascavella) may be a source in the bio-prospecting of new anti-hypertensive agents. The aim of this study was to investigate vascular effects of the venom of C.d. cascavella in normotensive rats. Studies were performed using isolated mesenteric artery segments and aortic endothelial cells. The cumulative administration of the venom of C.d. cascavella (0.001-30 μg/mL) on phenylephrine (Phe; 10 μM) pre-contracted rings induced a concentration-dependent vasorelaxation in the presence of vascular endothelium (Emax = 47...
April 18, 2017: Toxicon: Official Journal of the International Society on Toxinology
https://www.readbyqxmd.com/read/28424075/computational-modeling-of-airway-instability-and-collapse-in-tracheomalacia
#20
Scott J Hollister, Maximilian P Hollister, Sebastian K Hollister
BACKGROUND: Tracheomalacia (TM) is a condition of excessive tracheal collapse during exhalation. Both acquired and congenital forms of TM are believed to result from morphological changes in cartilaginous, fibrous and/or smooth muscle tissues reducing airway mechanical properties to a degree that precipitates collapse. However, neither the specific amount of mechanical property reduction nor the malacic segment lengths leading to life threatening airway collapse in TM are known. Furthermore, the specific mechanism of collapse is still debated...
April 19, 2017: Respiratory Research
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