With this communication, we would like to propose an update to the classification of propeller flaps, since after its publication, new flaps have been described that need to be included.
http://ift.tt/2lXkZ9U
Σάββατο 25 Φεβρουαρίου 2017
Axial propeller flaps: a proposal for update of the “Tokyo consensus on propeller flaps”
Permanent Implants for Lip Augmentation: results from a retrospective study and presentation of tips and tricks
The request for lip augmentation is increasing due to expanding media exposure and consumer needs. Temporary effects can be obtained with several techniques but a recent procedure, consisting of lip prosthesis implantation, offering a permanent result, is emerging. Accordingly, the implant of solid lip prosthesis represents an innovation in the field of aesthetic medicine and surgery.
http://ift.tt/2lIowWR
Conversion from weight to volume of mastectomy specimen: Convenient equations
Accurate restoration of the volume lost during breast removal is the key to achieving beautiful, symmetric breasts. This study aimed to devise a simpler and more accurate method of measuring breast tissue volume by studying the relationship between weight and volume of excised tissue according to density. Mammograms of 276 women who were advised to undergo breast reconstruction surgery were divided into 4 different groups according to tissue densities. The correlation between weight and volume was studied for each group.
http://ift.tt/2lXsGfW
Should we consider the hemi-tip as a proper aesthetic subunit in nasal reconstruction?
Defects involving several aesthetic subunits (ASU) or lying at the junction of an ASU are challenging and require a complex reconstruction. The purpose of this study was to describe the hemi-tip as a new ASU.
http://ift.tt/2lIynfa
Eponychial flap refinement for the treatment of “hook-nail” deformity
"Hook-nail" deformity mainly occurs after a fingertip injury. Loss of bony support under the nail bed leads to curving of the matrix in a volar direction resulting in aesthetic and functional impairment.1 Surgical procedures proposed have a significant failure rate.
http://ift.tt/2lXq9T4
The use of practice guidelines in the management of pediatric cases of Acute Otitis Media in Amman, Jordan
The widespread emergence of antimicrobial resistance has led many healthcare institutions to adopt more conservative antibiotic prescription practice guidelines for the treatment of acute otitis media (AOM). Little is known about the awareness and use of such guidelines by physicians in Jordan. Our aim was to pilot an anonymous survey instrument that would assess AOM treatment trends as well as awareness of and adherence to practice guidelines in Amman. By qualitatively assessing the management of AOM we could illuminate possible disparities in treatment trends, evaluate variability in practice guideline adherence, and help focus efforts of future educational programs that pertain to pediatric AOM management.
http://ift.tt/2mqSxdG
A new method for real-time evaluation of pepsin digestion of paraffin-embedded tissue sections, prior to fluorescence in situ hybridisation
Abstract
Fluorescence in situ hybridisation (FISH) is a molecular cytogenetic technique, which is regularly applied to formalin-fixed paraffin-embedded (FFPE) tissue sections of a variety of cancers to assess chromosomal aberrations. However, high-quality FISH requires optimal enzymatic digestion, and insufficient digestion is not noted until the hybridisation signals are evaluated in the fluorescence microscope. As a consequence, FISH results may be unreliable, and the experiment might have to be repeated. To solve this problem, we developed a new method for real-time evaluation of enzymatic tissue digestion. Termination of enzyme activity at the proper time facilitates successful hybridisation, and experiments do not have to be repeated. We first performed FISH on 20 FFPE samples, which had been pepsin digested for different times, and this revealed distinct morphological changes within the nucleus and perinuclear space that were detectable by light microscopy. These observations suggested that the presence of intact and clear bare nuclei, surrounded by a translucent perinuclear space, might serve as an indicator of adequate digestion. We developed a protocol for assessment of this indicator, based on morphological features, and applied this to a collection of 400 tissue samples, partly of breast cancer and partly of different types of lymphoma, prior to FISH. The FISH success rate was 99.5% (398/400), which was significantly higher than that of the conventional method. In all successful cases, morphological signs of adequate digestion were paralleled by easily interpretable FISH signals. This new method for the real-time assessment of digestion quality improved the success rate of FISH and in addition was simple and rapid.
http://ift.tt/2mj83vF
Phase I study of pazopanib plus TH-302 in advanced solid tumors
Abstract
Purpose
To define the maximum tolerated dose (MTD), recommended phase II dose (RPTD), and assess safety and tolerability for the combination of pazopanib plus TH-302, an investigational hypoxia-activated prodrug (HAP), in adult patients with advanced solid tumors.
Methods
This was an open-label, non-randomized, single-center, phase I trial consisting 2 stages. Stage 1 was a standard "3 + 3" dose escalation design to determine safety and the RPTD for TH-302 plus pazopanib combination. Stage 2 was an expanded cohort to better describe the tolerability and toxicity profile at the MTD. Pazopanib was orally dosed at 800 mg daily on days 1–28 for all cohorts. TH-302 was administered intravenously on days 1, 8 and 15 of a 28-day cycle at doses of 340 mg/m2 (cohort 1) or 480 mg/m2 (cohort 2). Dose limiting toxicity (DLT) was assessed in the first 28-day cycle. Efficacy was assessed every 2 cycles.
Results
Thirty patients were enrolled between December 2011 and September 2013. In the dose escalation stage, 7 patients were enrolled in the 340 mg/m2 TH-302 cohort and 6 patients in the 480 mg/m2 TH-302 cohort. Ten patients were evaluable for DLT. DLTs included grade 2 intolerable esophagitis (n = 1) in the 340 mg/m2 TH-302 cohort, and grade 3 vaginal inflammation (n = 1) and grade 3 neutropenia with grade 3 thrombocytopenia (n = 1, same patient) in the 480 mg/m2 TH-302 cohort. The 340 mg/m2 TH-302 cohort was determined to be MTD and RPTD. The most common treatment-related adverse events were hematologic (anemia, neutropenia, and thrombocytopenia), nausea/vomiting, palmar-plantar erythrodysesthesia syndrome, constipation, fatigue, mucositis, anorexia, pain, and hypertension. Partial response (PR) was observed in 10% (n = 3) of patients, stable disease (SD) in 57% (n = 17), and progressive disease (PD) in 23% (n = 7). Due to toxicity, 3 patients were discontinued from study drug prior to first radiographic assessment but were included in these calculations. Disease control ≥6 months was observed in 37% of patients (n = 11).
Conclusions
The RPTD for this novel combination is pazopanib 800 mg daily on days 1–28 plus TH-302 340 mg/m2 on days 1, 8 and 15 of each 28-day cycle. Preliminary activity was seen in treatment-refractory cancers and supports potential value of co-targeting tumor angiogenesis and tumor hypoxia.
http://ift.tt/2lbqkFU
Concise review of the management of iatrogenic emesis using cannabinoids: emphasis on nabilone for chemotherapy-induced nausea and vomiting
Abstract
Chemotherapy-induced nausea and vomiting (CINV) is a prevalent, distressing, and burdensome side effect of cancer chemotherapy. It is estimated to affect the majority of patients receiving certain anti-cancer drug regimens and can be treatment-limiting, even for life-saving medications. Despite seemingly numerous options, such as antimuscarinic anticholinergics, antihistamines, 5-HT3 receptor antagonists, dopamine receptor antagonists, and neurokinin-1 receptor antagonists, preventative therapies are often inadequately effective, particularly for "delayed CINV"—leaving an important unmet clinical need. Cannabinoid receptor agonists, by virtue of their unique mechanism of action and efficacy and safety data reported in clinical trials, appear to offer a useful additional option. The mechanistic value of cannabinoids has been well known for many years, but these agents may have been underutilized in the past because of the notoriety and legal status of marijuana. While botanical marijuana contains nearly 500 components, including the psychoactive tetrahydrocannabinol (THC), nabilone is an established, single-entity synthetic cannabinoid receptor agonist that has become the focus of renewed interest. We review the basic pharmacology and clinical trial data of nabilone for use in prophylaxis and treatment of CINV.
http://ift.tt/2lRqYwt
The effect of parathyroid hormone (1–84) treatment on serum bone morphogenetic protein 4 and vascular endothelial growth factor in postmenopausal women with established osteoporosis
Abstract
Purpose
To investigate the effect of 18 months' parathyroid hormone 1–84 (PTH 1–84) treatment on serum levels of bone morphogenetic protein 4 (BMP4) and vascular endothelial growth factor (VEGF), in postmenopausal women with established osteoporosis.
Methods
Thirty-seven postmenopausal women with osteoporosis (mean age 72.9 ± 8.1 years old) and 23 healthy controls (mean age 68.9 ± 9.9 years old) were enrolled. Patients were treated with daily subcutaneous injections of PTH (1–84) 100 mcg for 18 months, plus calcium 1 gr and vitamin D 800 IU per os daily. Blood samples were taken every 6 months during the study.
Results
At baseline, there were no differences considering anthropometric parameters, co-morbidities, current medications used between patients and controls. Mean serum VEGF levels were significantly higher in osteoporotic patients compared to controls (436.7 ± 259.7 vs. 260.3 ± 184.3 pg/ml, p = 0.006), while there were no differences in mean serum values of BMP4 (5.3 ± 1.7 vs. 5.7 ± 1.6 pg/ml, p = 0.40). Serum VEGF levels increased by approximately 20% after 12 months of PTH (1–84) treatment compared to baseline (p = 0.03) and by 22% after 18 months (p = 0.01). A significant increase of 10% in mean serum BMP4 levels was observed after 18 months of PTH (1–84) treatment compared to baseline (p = 0.02). In the control group we found no differences after 18 months compared to baseline in BMP4 (5.7 ± 1.6 vs. 6.0 ± 1.5 pg/ml, p = 0.53) and VEGF (260.3 ± 184.3 vs. 257.4 ± 107.1 pg/ml, p = 0.94).
Conclusions
PTH (1–84) treatment increased serum levels of VEGF and BMP4 in postmenopausal women with severe osteoporosis.
http://ift.tt/2lSlCkm
Challenges in assessing personality of individuals with Gender Dysphoria with the SWAP-200
Abstract
Background
Personality assessment can be useful to better understand the complexity of transgender and transsexual people. In particular, the Shedler Westen Assessment Procedure-200 (SWAP-200) is a measure that provides an accurate dimensional evaluation of personality. When assessing gender non-conforming people, however, clinicians can encounter some difficulties in giving appropriate ratings to all the items.
Purpose of the review
A brief guide to the use of SWAP-200 with transgender patients is provided, taking into account three areas of psychological functioning: identity, relationships and sexuality. The authors review, one by one, the SWAP-200 items related to these areas, and, relying on their clinical experience and on scientific literature on Gender Dysphoria, they propose recommendations for making personality diagnoses meaningful.
Conclusion
This paper facilitates a better clinical understanding of transgender people, and help clinicians to be more knowledgeable in the assessment of this heterogeneous population.
http://ift.tt/2mxblaD
Tough and ultrastretchable hydrogels reinforced by poly(butyl acrylate-co-acrylonitrile) latex microspheres as crosslinking centers for hydrophobic association
Publication date: 10 March 2017
Source:Polymer, Volume 112
Author(s): Wei Zhao, Lijie Duan, Baoyuan Zhang, Xiuyan Ren, Guang Hui Gao
In our previous work, poly(butyl acrylate) (PBA) latex microspheres (LMs) were embedded within hydrogels to enhance their mechanical strength. Herein, acrylonitrile (AN) components were added to the latex system to prepare novel poly(butyl acrylate-acrylonitrile) (P(BA-AN)) LMs. LMs were able to adsorb hydrophobic hexadecyl methacrylate (HMA) due to hydrophobic interactions, stabilized by using sodium dodecyl sulfate as a surfactants. The HMA could occur radical copolymerization with acrylamide (AAm) under the redox initiators to form P(HMA-AAm)-P(BA-AN) hydrogels. The intra and interchain non-permanent binding could be promoted in P(BA-AN) LMs due to the dipole-dipole interactions of -CN groups from acrylonitrile. As a result, P(BA-AN) LMs were utilized to fabricate tough hydrogels as crosslinking centers for hydrophobic association. The mechanical properties of the hydrogels exhibited a fracture stress of 775 KPa, an ultrastretchable strain of 3600% and a fracture energy of approximately 7600 KJ/m3. This innovative design strategy for LMs capable of strong physicochemical interactions, including electrostatic and hydrogen-bond interactions and coordination effects, may open a novel direction for the production of tough hydrogels.
Graphical abstract
http://ift.tt/2miTp7C
Viscoelastic and electrical behavior of poly(methyl methacrylate)/carbon black composites prior to and after annealing
Publication date: 24 March 2017
Source:Polymer, Volume 113
Author(s): Yamin Pan, Xianhu Liu, Joachim Kaschta, Xiaoqiong Hao, Chuntai Liu, Dirk W. Schubert
In this letter, both the viscoelastic and electrical properties of poly(methyl methacrylate)/carbon black (PMMA/CB) nanocomposites with different CB concentrations prior to and after annealing were investigated. The linear steady-state recoverable compliance of pure PMMA is independent of annealing as it reflects only polymer-polymer interactions. While the conductivity of PMMA/CB nanocomposites increases gradually with annealing, and the viscoelastic properties show different regions of response depending on the CB concentration. At CB contents below the percolation threshold the recoverable compliances increase after annealing, whereas the reverse trend is found at CB contents above the percolation threshold. This behavior is related to the interplay between network formation and particle-particle interactions.
Graphical abstract
http://ift.tt/2miUH2k
Interfacial molecular dynamics of styrenic block copolymer-based nanocomposites with controlled spatial distribution
Publication date: 24 March 2017
Source:Polymer, Volume 113
Author(s): E. Helal, L.G. Amurin, D.J. Carastan, R.R. de Sousa, E. David, M. Fréchette, N.R. Demarquette
The dielectric properties of nanocomposites of polystyrene-b-poly (ethylene-co-butylene)-b-polystyrene (SEBS) triblock copolymers containing organically modified clay nanoparticles featuring controlled spatial orientation at the nanoscale: isotropic, totally oriented and partially oriented, have been investigated and correlated with the nanocomposite morphologies. A slow dielectric relaxation process attributed to elastomer chains with reduced mobility confined at nanoparticle/polymer interphase was observed in all the nanocomposites and was found to be dependent on the orientation of nanoclay and polystyrene (PS) domains, the location of clay tactoids as well as the PS block fraction. A dielectric "interfacial" glass transition temperature Tgi assigned to this characteristic relaxation was estimated to occur at temperatures ranging between 6 °C and 35 °C depending on the nanocomposite, which is much higher than the bulk rubber phase glass transition temperature, normally lower than −40 °C for the studied block copolymers. Interestingly, the highest Tgi were associated with the nanocomposites featuring random or partial orientation and/or selective location of nanoparticles in the rubber phase.
Graphical abstract
http://ift.tt/2miHYfV
Molecular confinement of solid and gaseous phases of self-standing bulk nanoporous polymers inducing enhanced and unexpected physical properties
Publication date: 24 March 2017
Source:Polymer, Volume 113
Author(s): Javier Pinto, Belen Notario, Raquel Verdejo, Michel Dumon, Stephane Costeux, Miguel Angel Rodriguez-Perez
In this work it is provided the first evidence of the polymer chains confinement within self-standing pore walls of nanoporous materials based on poly (methyl methacrylate) (PMMA). This was made possible by producing a series of porous samples with a wide range of pore sizes between 90 nm and 3 μm using processes combining CO2 sorption, selective block copolymer swelling or homogeneous physical foaming. Mobility restrictions of the PMMA chains in the porous samples with pore size below 200 nm was consistently demonstrated with several experimental techniques, including differential scanning calorimetry, Raman spectroscopy, and broadband dielectric spectroscopy.In addition, several scale-reduction phenomena related to the constitutive elements of the porous materials, both in the polymeric and gaseous phases, and to the porous architecture are identified. The significance of these phenomena on macroscopic electrical conductivity and permittivity of the nanoporous materials is demonstrated, and the presented observations support previous explanations of improved mechanical properties and thermal insulation of this type of nano-materials.
Graphical abstract
http://ift.tt/2miRrnG
Protein-polyelectrolyte complexes: Molecular dynamics simulations and experimental study
Publication date: 24 March 2017
Source:Polymer, Volume 113
Author(s): Alina A. Sofronova, Diana B. Evstafyeva, Vladimir A. Izumrudov, Vladimir I. Muronetz, Pavel I. Semenyuk
Despite use of polyelectrolytes is considered to be a prospective approach of protein aggregation suppression, owing to formation of soluble protein-polyelectrolyte complexes, the structure of the complexes and mechanism of their formation are not sufficiently understood. The aim of this work was to study the influence of degree of polymerization on the structure and properties of formed complexes. We carried out molecular dynamics simulations of complexes of cationic protein lysozyme with highly charged polyanions – poly(styrene sulfonate) and polyphosphate – of different degree of polymerization. It has been shown that the short charged chains are bound with the protein via a great majority of repeat units, while the long chains have unbound fragments that form charged loops and tails around the protein surface. These loops were earlier suggested to provide stability of the complex. Furthermore, the charge of the complex increased with increasing length of chain. These findings are consistent with the experimentally measured zeta potential. The obtained results help to explain why polyanion protective efficiency against protein aggregation increases with increase of the degree of polymerization.
Graphical abstract
http://ift.tt/2miVa4z
Hybrid triazolium and ammonium ions-contained hyperbranched polymer with enhanced ionic conductivity
Publication date: 10 March 2017
Source:Polymer, Volume 112
Author(s): Hongfei Li, Cuifang Wang, Xiaojuan Liao, Meiran Xie, Ruyi Sun
Hyperbranched poly(triazole) with tertiary amine moiety and longer flexible polyethylene glycol (PEG) terminal group (hb-PTA-PEG) was synthesized by successive Cu(I)-catalyzed azide-alkyne cycloaddition polymerization, and the corresponding hyperbranched poly(triazolium)s containing hybrid quaternary ammonium ion, [hb-PTA-PEG]+[I]− and [hb-PTA-PEG]+[TFSI]−, were obtained after N-alkylation and anion exchange reactions. These hyperbranched polymers presented broad electrochemical stability window of above 6.0 V versus Ag+/Ag and 5.3 V versus Li+/Li, and displayed low glass transition temperature in the range of −13 to −37 °C, owing to the hyperbranched structure combined with the hybrid ionic moiety and longer flexible PEG end-group. The ionic [hb-PTA-PEG]+[TFSI]− showed superior ionic conductivity, which was above 10−5 S cm−1 at 30 °C.
Graphical abstract
http://ift.tt/2miVYXd
Facile synthesis and hierarchical assembly of polystyrene-block- poly (perfluorooctylethyl acrylates)
Publication date: 24 March 2017
Source:Polymer, Volume 113
Author(s): Hui Dai, Guang-Zhong Yin, Fang-Jia Zhao, Zhong-Xuan Bian, Yu-Jie Xu, Wen-Bin Zhang, Xia-Ran Miao, Hui Li
Hierarchical assembly of macromolecules has been central in creating complex nanostructures. In this work, polystyrene-block-poly (perfluorooctylethyl acrylates) (PS-b-PFOA) diblock copolymers were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization and shown to assemble into hierarchical structures in bulk with the interplay of nanophase separation and crystallization. The molecular weights were determined by gel permeation chromatography (GPC) and 1H NMR spectra. The phase-separated nanostructures of these block copolymers were investigated via small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD) in reciprocal space and by transmission electron microscopy (TEM) in real space. The results showed that well-ordered lamellar morphologies were formed in the bulk of samples with volume fraction of PFOA (fPFOA) around 0.390–0.538. Within the PFOA layers, the side chains were found to further crystallize, forming crystalline layers with thicknesses about twice that of the length of fluorinated side-chains. The SAXS patterns from sheared samples further show that the orientation of crystalline layers was perpendicular to the lamellar layers formed by micro-phase separation.
Graphical abstract
http://ift.tt/2miNEqi
Crystalline microstructure and dielectric properties of oriented poly(ethylene-co-tetrafluoroethylene)
Publication date: 24 March 2017
Source:Polymer, Volume 113
Author(s): Yun Huang, Daniel F. Miranda, Ciprian Iacob, Shihai Zhang, James Runt
In the present investigation, we explore the influence of uniaxial orientation and subsequent thermal annealing on semi-crystalline poly(ethylene-tetrafluoroethylene) (ETFE) microstructure and dynamics, and the connection to dielectric breakdown strength. Understanding the influence of crystalline microstructure on dynamics and breakdown, and in turn how processing influences microstructure, is critical for establishing rational design of polymer dielectrics. When drawn below the glass transition temperature (Tg), the Weibull breakdown strength decreases compared to that of the undrawn precursor film, but increases on thermal annealing near or above Tg. This behavior is associated with the formation and elimination of drawing-induced microvoids, respectively. When drawn above Tg, the breakdown strength increases to ∼870 MV/cm, dominated by orientation of amorphous segments, and decreases on thermal annealing above Tg to near that of the undrawn film.
Graphical abstract
http://ift.tt/2miNGhU
Noncovalent azopoly(ester imide)s: Experimental study on structure-property relations and theoretical approach for prediction of glass transition temperature and hydrogen bond formation
Publication date: 24 March 2017
Source:Polymer, Volume 113
Author(s): Jolanta Konieczkowska, Henryk Janeczek, Jan Małecki, Barbara Trzebicka, Dariusz Szmigiel, Anna Kozanecka-Szmigiel, Ewa Schab-Balcerzak
Novel azosystems possessing chemical architecture that allows for noncovalent attachment of the azobenzene or azopyridine chromophores to poly(ester imide) matrix via hydrogen bonding were fabricated. Chosen physicochemical properties including the ability of the chromophores to realign upon linearly polarized light were determined and discussed in relation to details of the materials structure. Calculations based on density functional theory (DFT) were employed to understand and explain a structural reason affecting hydrogen bond formation ability and photoresponsive behavior of the studied azosystems. For the first time, the Fox equation was shown to be applicable for calculating the glass transition temperature of hydrogen-bonded azopolymers. Moreover, it was demonstrated that azopyridine polymers may exhibit a very efficient molecular photo-orientation provided that they possess a proper structural design.
Graphical abstract
http://ift.tt/2miTfNi
Generation effect of Newkome dendrimers on cellular uptake
Publication date: 24 March 2017
Source:Polymer, Volume 113
Author(s): Elizabeth A. Kaufman, Rossella Tarallo, Annarita Falanga, Stefania Galdiero, Marcus Weck
Poly(amide)-based dendrimers can be used as delivery scaffolds in conjunction with the cell-penetrating peptide gH625 derived from the glycoprotein of the Herpes Simplex virus type 1. In this contribution, we aim to isolate the optimal dendrimer generation for cellular uptake for Newkome type dendrimers conjugated with gH625. For this study, we synthesized generations zero to three of the Newkome dendrimer-gH625 bioconjugate. Fluorescent microscopy experiments showed that the second and third generations are the most efficient for cellular uptake with the second generation having the synthetic advantage. The optimal second generation can be used as an improved material for a dendrimer based delivery scaffold for peptide therapeutics.
Graphical abstract
http://ift.tt/2miSkN5
Effect of fused layer modeling (FLM) processing parameters on impact strength of cellular polypropylene
Publication date: 24 March 2017
Source:Polymer, Volume 113
Author(s): Lu Wang, Douglas J. Gardner
Fused layer modeling (FLM) or fused deposition modeling (FDM) can be used to produce polymer components with a cellular structure. The existence of cells (voids) in FLM parts degrades mechanical properties. This study was done to understand the influence of two printing parameters, layer height (0.1 mm and 0.3 mm) and extrusion temperature (200 °C and 250 °C), on the Izod impact strength of polypropylene (PP). Morphological analysis showed that smaller layer height and higher extrusion temperature generally resulted in smaller cell size but larger cell density. Printed PP components were lighter than injection molded PP parts. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analyses confirmed that both α and β type crystals existed in printed PP. PP printed at 250 °C had lower impact strength while components printed at 200 °C had similar impact strength to injection molded PP.
Graphical abstract
http://ift.tt/2miRsYM
Polylactic acid organogel as versatile scaffolding technique
Publication date: 24 March 2017
Source:Polymer, Volume 113
Author(s): Xavier Punet, Riccardo Levato, Isabelle Bataille, Didier Letourneur, Elisabeth Engel, Miguel A. Mateos-Timoneda
Tissue engineering requires scaffolding techniques based on non-toxic processes that permits the fabrication of constructs with tailored properties. Here, a two-step methodology based on the gelation and precipitation of the poly(lactic) acid/ethyl lactate organogel system is presented. With this technique nanofibrous matrices that resemble natural extracellular matrix can be easily obtained, while allowing control over the mechanical properties of the device. Gelation temperature and the dynamics of the gelation of the organogel system are characterized, and the final mechanical and viscoelastic properties, as well as porosity, as function of the initial polymer concentration are described. We show that gelation temperature of the system is concentration independent and below 44.5 °C, which permits gelation at room temperature. Furthermore, mechanical properties are found in the range of the soft organic tissues, and the obtained micro-network architecture gives place to a flexible structure. Such structure presents tuneable elastic modulus and viscoelastic properties as function of nanofibers density. Moreover, centimetre-long tubular scaffolds with the diameter of medium-caliber blood vessels were produced. The fibrous nano-architecture mimics the native extracellular matrix fibres diameter and morphology was proven to be suitable to support endothelialization of the lumen of the tube. Thus, this strategy, based on biocompatible green compound might be promising for the fabrication of large 3D scaffolds for tissue engineering applications.
Graphical abstract
http://ift.tt/2miTJD3
Unveiling the impact of nanoparticle size dispersity on the behavior of polymer nanocomposites
Publication date: 24 March 2017
Source:Polymer, Volume 113
Author(s): J. Javier Burgos-Mármol, Alessandro Patti
Polymer nanocomposites (PNCs), a class of polymer materials incorporating nano-sized particles (NPs), have tremendous potential in industrial formulations and technological applications, such as protective coatings and food packaging. In this work, we perform Molecular Dynamics simulations to unveil the impact of NP size dispersity on a variety of properties that characterize the response of PNCs at the nano and macro scales. In particular, at the nano scale, we investigate the space distribution of small and large polydisperse NPs and their ability to diffuse through a dense isotropic distribution of unentangled polymer chains. We find very interesting scaling laws relating the average size and polydispersity index of NPs with their diffusion coefficients, generally underestimated by existing theoretical models. These theories are here adapted to include the effect of NP size dispersity and their predictions, confirming the relevance of incorporating such contributions, are validated against our simulation results. We also analyze the diffusivity of the polymer chains as a function of the interparticle distance for a spectrum of NP diameters and confirmed the existence of a single master curve as recently observed experimentally (S. Gam et al., Soft Matter, 2012, 8, 6512). To assess the effect of NP size dispersity on the macroscopic response of our model PNC, we evaluate two key transport properties, shear viscosity and thermal conductivity, which are found to display an intriguing universal behavior when plotted against the polymer/NP specific interface area and the inverse of the NP's mass, respectively.
Graphical abstract
http://ift.tt/2miJBdM
A new approach to fabricate polypropylene alloy with excellent low-temperature toughness and balanced toughness-rigidity through unmatched thermal expansion coefficients between components
Publication date: 10 March 2017
Source:Polymer, Volume 112
Author(s): Yonggang Shangguan, Feng Chen, Jie Yang, Erwen Jia, Qiang Zheng
A new strategy for fabricating polypropylene alloy with good low-temperature toughness was reported. Glass transition temperature (Tg) of rubber phase in polypropylene/ethylene-propylene rubber/poly(styrene-b-ethylene/propylene) diblock copolymer (PP/EPR/SEP) blend was continuously reduced through strengthening the interfacial tensile force on rubber phase by using the concept of mismatched thermal expansion coefficient. As a result, the brittle-tough transition (BTT) of PP alloy shifted to lower temperature and subsequently excellent impact strength at low temperature was achieved. Through qualitative analysis of impact force, it was found that the theoretical temperature at which BTT occurred was close to that obtained by experiment, indicating BTT of rubber toughened plastic system is indeed controlled by rubber's Tg at impact instant. Furthermore, the PP alloy with excellent low-temperature toughness shows balanced toughness-rigidity, on the contrary, the blends presents poor rigidity when SEP or EPR is used to toughen PP alone.
Graphical abstract
http://ift.tt/2miVhgi
Pressure-sensitive behaviors, mechanisms and model of field assisted quantum tunneling composites
Publication date: 24 March 2017
Source:Polymer, Volume 113
Author(s): Siqi Ding, Baoguo Han, Xufeng Dong, Xun Yu, Yiqing Ni, Qiaofeng Zheng, Jinping Ou
Field assisted quantum tunneling composite (FAQTC) is a unique pressure-sensitive material with the advantages of large resistance change range under external force, easy preparation and excellent mechanical properties. In this paper, with attentions to the pressure-sensitivity of the FAQTCs, the effects of silicon rubber matrix, diameter and dosage of nickel particles as well as magnetic field treatment are systematically investigated. The reproducibility of the pressure-sensitivity of the FAQTCs under cyclic load is explored. Based on Cotton's equation and Burger's model, the descriptions of stress relaxation behavior and electrical resistance relaxation behavior of the composites under static compressive loading are given respectively. The results show that external magnetic field during curing process allows better adjustment of the pressure-sensitivity of the FAQTCs with fewer nickel particles. The increase of the dosage of nickel particles can improve the stability and reproducibility of the pressure-sensitivity of the composites. Electrical resistance relaxation behavior of the composites is partly controlled by the stress relaxation behavior. Moreover, based on the theory of percolation conduction, the mechanism of the pressure-sensitivity of the FAQTCs under uniaxial load is discussed and further qualitatively explained by adopting effective conducting path model. Finally, on the basis of this model combined with quantum tunneling effect, a mathematical model describing the pressure-sensitivity of the composites is established, which can well describe the pressure-sensitivity of the composites.
Graphical abstract
http://ift.tt/2miUJat
Polyaniline film-based wireless photo reactor for hydrogen generation through exciton mediated proton reduction
Publication date: 10 March 2017
Source:Polymer, Volume 112
Author(s): Smita Masid Roy, Nageswara N. Rao, Alexandre Herissan, Christophe Colbeau-Justin
The unique light absorption property of semiconductors has been exploited to build photovoltaic (PV), photo electrochemical solar cells (PESC) and photocatalytic (PC) reactors that not only convert sunlight into electrical energy but also drive useful chemical reactions. Hydrogen, the clean fuel of 21st century has been targeted for several decades. However, the above systems possess complex architecture with two or more semiconductor-solution interfaces that are often plagued with material instability and show poor photon conversion efficiency. Here we demonstrate a simple pristine polyaniline (PANI) film based photo H2 generating system. The 'wireless' system with only one PANI/solution interface, utilizes internal redox chemistry in the conjugated polymer for 'photo exciton' formation and charge separation. The electrons migrate to the PANI/aq. H2SO4 interface and reduce H+ to produce H2. The polymer film is light weight, flexible, and solution-processable. The reported system is simple and scalable for high volume production of hydrogen.
Graphical abstract
http://ift.tt/2miVjou
Crosslinked membranes of poly(vinyl ether)s having oxyethylene side chains: The effects of the side chain length and the crosslinkable group on CO2 permeability
Publication date: 10 March 2017
Source:Polymer, Volume 112
Author(s): Toshikazu Sakaguchi, Shinya Yamazaki, Tamotsu Hashimoto
Living cationic copolymerization of vinyl ethers having oxyethylene side chains (MOEO3VE and MOEO4VE) with vinyl ethers having thermal-crosslinkable groups (VEEM and VEEA) provided the random-like copolymers [poly (MOEO3VE-VEEM), poly (MOEO4VE-VEEM), poly (MOEO3VE-VEEA), and poly (MOEO4VE-VEEA)]. The obtained copolymer compositions were almost the same as those of the feed ratios, and the copolymers with various composition ratios were synthesized ([MOEO3VE or MOEO4VE]/[VEEM or VEEA] = 2:1, 4:1, 6:1, 10:1, and 14:1). All the copolymers are sticky liquid before crosslinking, but the relatively tough porous Teflon film-based composite membranes were obtained by thermal crosslinking via mathacrylate groups or acrylate groups. All the membranes showed high CO2 permselectivity (PCO2/PN2 = 40–51) due to the high CO2 solubility selectivity (SCO2/SN2 = 44–61). The CO2 permeability increased as the composition ratios of VEEM and VEEA decreased because the gas diffusivity enhanced by the decrement of crosslinking points. Given the same composition ratio, the increased oxyethylene side chain length is beneficial in enhancing CO2 permeability. The effects of crosslinkable groups on gas permeability were not observed. Poly (MOEO4VE-VEEM) and poly (MOEO4VE-VEEA) showed the excellent performance for CO2 separation (PCO2 = 440 and 460 barrer, PCO2/PN2 = 51).
Graphical abstract
http://ift.tt/2miHZAv
Sustainable poly(ε-decalactone)−poly(l-lactide) multiarm star copolymer architectures for thermoplastic elastomers with fixed molar mass and block ratio
Publication date: 10 March 2017
Source:Polymer, Volume 112
Author(s): Sangjun Lee, Kyungchan Lee, Jeongmin Jang, Ji Sun Choung, Woo Jin Choi, Geon-Joong Kim, Young-Wun Kim, Jihoon Shin
To improve the thermal and mechanical properties of thermoplastic elastomers derived from plant-based monomers, a series of well-defined multiarm star block copolymers was investigated. Controlled bulk ring-opening polymerization of ε-decalactone (DL) with multiarm initiators yielded hydroxyl-terminated (PDL−OH)n, which were subsequently converted to (PDL−PLLA)n using l-lactide (LLA) through a one-pot, two-step process. The multiarm copolymers were designed for targeting on Mn,NMR and fPLLA of 180 kg mol−1 and 0.27, respectively. Structural analysis proved that PLLA hard domains were thinner, and thus, more compact microphase-separated structures with hexagonally packed cylinders were induced by increasing n. Thermal and tensile property measurement demonstrated that, although the copolymers had a lower crystallinity in PLLA due to the shorter chain length, the thermal degradation stability and mechanical strength were enhanced, which was caused by to an amplified pinning effect caused by the more closed packed PLLA domains, in addition to chemical crosslinking of the PDL strands.
Graphical abstract
http://ift.tt/2miH1Ey
Guanidinium functionalized polypeptide nanogels as the phosphate binder
Publication date: 10 March 2017
Source:Polymer, Volume 112
Author(s): Yuling Sun, Xiangxue Lyu, Zhibo Li, Yanbin Huang
Phosphate-binding particles are clinically used to reduce the phosphate level in patients with chronic kidney diseases. However, the binding efficiency of the current amino-functional polymers is low, resulting in high pill burden and low patient adherence. Here, we used polylysine nanogels with amino- and guanidinium-functional groups (PLL nanogel and GPLL nanogel), respectively, and experimentally proved that guanidinium is a much more efficient phosphate-binding group than the amino group at all the tested conditions. The phosphate binding amount of the GPLL nanogel is 60% higher than that of the PLL nanogel at pH 7, 55% higher at pH 2, and 30% higher in the presence of 150 mM NaCl. This guanidination strategy should also be applicable to non-polypeptide systems for anion sequestration. Though the difference of amino and guanidinium functional groups interacting with phosphate ions had been known in the literature, this is the first experimental study to directly compare their phosphate binding performance in clinically relevant conditions (e.g., crosslinked particle forms with all the other parameters controlled to be the same). Therefore, guanidinium functionalized polymers have the potential to become the new generation therapeutics.
Graphical abstract
http://ift.tt/2miQjQP
Tungstate-loaded triazine-based magnetic poly(Bis-imidazolium ionic liquid): An effective bi-functional catalyst for tandem selective oxidation/Knoevenagel condensation in water
Publication date: 10 March 2017
Source:Polymer, Volume 112
Author(s): Nasrin Zohreh, Maryam Tavakolizadeh, Seyed Hassan Hosseini, Ali Pourjavadi, Craig Bennett
A novel bi-functional polymeric catalyst was synthesized by immobilization of tungstate anions onto the nitrogen rich poly(ionic liquid)/magnetic nanocomposite. The resulting catalyst has two types of catalytic sites: (i) immobilized WO4 anions with bis-imidazolium ionic liquid cation for selective oxidation of alcohols and (ii) basic amine groups for Knoevenagel condensation between produced aldehyde and malononitrile. Due to the polymeric nature of the catalyst, large amounts of tungstate and basic nitrogen groups were presented on the solid surface which led to a decrease in the applied catalyst mass for catalytic reaction. High catalytic activity and excellent selectivity of catalyst in water medium make this protocol a green way for production of fine chemicals.
Graphical abstract
http://ift.tt/2miV9xx
Combining talimogene laherparepvec with immunotherapies in melanoma and other solid tumors
Abstract
Talimogene laherparepvec is a first-in-class intralesional oncolytic immunotherapy. In a recent Phase III trial (OPTiM), talimogene laherparepvec significantly improved durable response rate compared with subcutaneous granulocyte–macrophage colony-stimulating factor (GM-CSF). Overall response rate was also higher in the talimogene laherparepvec arm, and the greatest efficacy was demonstrated in patients with earlier-stage (IIIB, IIIC, or IVM1a) melanoma. Talimogene laherparepvec was well tolerated, with the majority (89%) of adverse events being grade 1 or 2. Preclinical studies have shown that talimogene laherparepvec exerts antitumor activity by selectively replicating within and destroying cancer cells, and through the release of tumor-associated antigens and expression of GM-CSF, which facilitates a wider antitumor immune response. It is hypothesized that combining talimogene laherparepvec with a systemic immunotherapy may, by bringing together complementary mechanisms of action, further enhance the efficacy of both agents. Indeed, talimogene laherparepvec is currently being assessed in combination with immune checkpoint inhibitors, including ipilimumab and pembrolizumab, in trials for melanoma and other solid tumors. Early results in melanoma indicate that the combination of talimogene laherparepvec with ipilimumab or pembrolizumab has greater efficacy than either therapy alone, without additional safety concerns above those expected for each monotherapy. In this review, we discuss the latest results from trials assessing talimogene laherparepvec in combination with other immunotherapies, provide an overview of ongoing and upcoming combination trials, and suggest future directions for talimogene laherparepvec in combination therapy for solid tumors.
http://ift.tt/2lafJuS
Expression of VISTA correlated with immunosuppression and synergized with CD8 to predict survival in human oral squamous cell carcinoma
Abstract
V-domain Ig suppressor of T cell activation (VISTA), a novel immune checkpoint regulatory molecule, suppresses T cell mediated immune responses. The aim of the present study was to profile the immunological expression, clinical significance and correlation of VISTA in human oral squamous cell carcinoma (OSCC). Human tissue microarrays, containing 165 primary OSCCs, 48 oral epithelial dysplasias and 43 normal oral mucosae, were applied to investigate the expression levels of VISTA, CD8, cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), programmed death ligand 1 (PD-L1), PI3Kα p110, IL13Rα2, phospho-STAT3 at tyrosine 705 (p-STAT3) and myeloid-derived suppressor cell (MDSC) markers (CD11b and CD33) by immunohistochemistry and digital pathology analysis. The results demonstrated that the protein level of VISTA was significantly higher in human OSCC specimens, and that VISTA expression in primary OSCCs was correlated with lymph node status. VISTA expression did not serve as an independent predictor for poor prognosis, while patient subgroup with VISTA high and CD8 low expression (22/165) had significantly poorer overall survival compared with other subgroups based on the multivariate and Cox hazard analyses among the primary OSCC patients in the present cohort. Additionally, the expression of VISTA was significantly correlated with PD-L1, CTLA-4, IL13Rα2, PI3K, p-STAT3, CD11b and CD33 according to Pearson's correlation coefficient test. Taken together, the results indicated that the VISTA high and CD8 low group, as an immunosuppressive subgroup, might be associated with a poor prognosis in primary OSCC. These findings indicated that VISTA might be a potential immunotherapeutic target in OSCC treatment.
http://ift.tt/2mxLqzw
Safety of UV Lamps for Cosmetic Use: Regulatory Considerations [Free article]
Electrochemotherapy for the Treatment of Unresectable Locoregionally Advanced Cutaneous Melanoma: A Systematic Review [Free article]
Merkel Cell Carcinoma: An Update of Key Imaging Techniques, Prognostic Factors, Treatment, and Follow-up [Free article]
Update on Merkel Cell Carcinoma: Epidemiology, Etiopathogenesis, Clinical Features, Diagnosis, and Staging [Free article]
Consensus-Based Acne Classification System and Treatment Algorithm for Spain [Free article]
Treatment of nail psoriasis with Pulse Dye Laser plus calcipotriol betametasona gel vs. Nd:YAG plus calcipotriol betamethasone gel: An intrapatient left-to-right controlled study [Free article]
Solar Urticaria: Epidemiology and Clinical Phenotypes in a Spanish Series of 224 Patients [Free article]
Clinical Characteristics and Outcomes in a Population With Disseminated Herpes Zoster: A Retrospective Cohort Study [Free article]
Treatment of Bowen Disease With Photodynamic Therapy and the Advantages of Sequential Topical Imiquimod [Free article]
Glomeruloid Hemangioma and POEMS Syndrome [Free article]
Long-standing Scaly Erythematous Tumor on the Lower Leg [Free article]
Long-standing Papules on the Scrotum [Free article]
Subcutaneous Nodules in a Kidney Transplant Recipient: Familial Multiple Lipomatosis [Free article]
A Scar or a Tumor? [Free article]
Doppler Ultrasound of Aneurysmal Dermatofibroma [Free article]
Familial Mediterranean Fever: Diagnostic Difficulties in an Atypical Case [Free article]
Retrospective Observational Epidemiologic Study of Sensitization to Gold Sodium Thiosulfate in the Allergy Clinic of a Tertiary Hospital [Free article]
Isotretinoin-Induced Elkonyxis [Free article]
A Case Series of Patients With Psoriasis Exposed to Biologic Therapy During Pregnancy: The BIOBADADERM Register and a Review of the Literature [Free article]
Metastatic Crohn Disease [Free article]
Complications and Cost Analysis of Intraoperative Arterial Complications in Head and Neck Free Flap Reconstruction
J reconstr Microsurg
DOI: 10.1055/s-0037-1598618
Background Microvascular anastomotic patency is fundamental to head and neck free flap reconstructive success. The aims of this study were to identify factors associated with intraoperative arterial anastomotic issues and analyze the impact on subsequent complications and cost in head and neck reconstruction. Methods A retrospective review was performed on all head and neck free flap reconstructions from 2005 to 2013. Patients with intraoperative, arterial anastomotic difficulties were compared with patients without. Postoperative outcomes and costs were analyzed to determine factors associated with microvascular arterial complications. A regression analysis was performed to control for confounders. Results Total 438 head and neck free flaps were performed, with 24 (5.5%) having intraoperative arterial complications. Patient groups and flap survival between the two groups were similar. Free flaps with arterial issues had higher rates of unplanned reoperations (p < 0.001), emergent take-backs (p = 0.034), and major surgical (p = 0.002) and respiratory (p = 0.036) complications. The overall cost of reconstruction was nearly double in patients with arterial issues (p = 0.001). Regression analysis revealed that African American race (OR = 5.5, p < 0.009), use of vasopressors (OR = 6.0, p = 0.024), end-to-side venous anastomosis (OR = 4.0, p = 0.009), and use of internal fixation hardware (OR =3.5, p = 0.013) were significantly associated with arterial complications. Conclusion Intraoperative arterial complications may impact complications and overall cost of free flap head and neck reconstruction. Although some factors are nonmodifiable or unavoidable, microsurgeons should nonetheless be aware of the risk association. We recommend optimizing preoperative comorbidities and avoiding use of vasopressors in head and neck free flap cases to the extent possible.
[...]
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Article in Thieme eJournals:
Table of contents | Abstract | Full text
http://ift.tt/2lmfr53
Entering Into Suffering: Becoming a Transformed and Transforming Healer
http://ift.tt/2mioPLc
Respite Care for Families of Children with Disabilities: A University/Faith Community Model
http://ift.tt/2miDKFf
Understanding Spiritual Care: The Faith-Hope-Love Model of Spiritual Wellness
http://ift.tt/2lbNHPy
The Pad Project: A Global Initiative Uniting Women
http://ift.tt/2lboNzQ
Trauma-Informed Care: Helping Patients with a Painful Past
http://ift.tt/2lbDaUE
Equipping African American Clergy to Recognize Depression
http://ift.tt/2lbKSOu
Strategies for Improving Nursing Students' Mental Health Clinical Rotation
http://ift.tt/2miqW1t
Surviving (Even Thriving?) in a Toxic Workplace
http://ift.tt/2miwzNf
A Compassionate Visitation Program for Church Homebound Elders
http://ift.tt/2miEES1
Acute corneal hydrops during pregnancy with spontaneous resolution after corneal cross-linking for keratoconus: a case report
Keratoconus may progress to acute corneal hydrops even after cross-linking. In some cases, keratoconus progresses during pregnancy. In this report, we present a case of a patient with increased anterior stroma...
http://ift.tt/2lW6z9X
Acute corneal hydrops during pregnancy with spontaneous resolution after corneal cross-linking for keratoconus: a case report
Keratoconus may progress to acute corneal hydrops even after cross-linking. In some cases, keratoconus progresses during pregnancy. In this report, we present a case of a patient with increased anterior stroma...
http://ift.tt/2lW6z9X
The sensitization pattern differs according to rhinitis and asthma multimorbidity in adults: the EGEA study
Abstract
Background
Mono- and polysensitization are different IgE-mediated allergic phenotypes in children. Allergic sensitization is associated with both allergic asthma and allergic rhinitis, however, associations between the sensitization pattern and particularly polysensitization with asthma and rhinitis remains poorly studied in adults.
Aim
The aim of this study was to assess how the allergic sensitization pattern associates with asthma, rhinitis and their multimorbidity.
Methods
1,199 adults from the EGEA study, with extensive phenotypic characterization and all data available on skin prick tests to 10 allergens, total IgE and blood eosinophils were included. Using questionnaires only, participants were classified into 6 groups: asymptomatic (no asthma, no rhinitis), non-allergic rhinitis alone, allergic rhinitis alone, asthma alone, asthma+non-allergic rhinitis and asthma+allergic rhinitis. Mono- and polysensitization were defined by a positive skin prick test to one or more than one allergen respectively.
Results
Asymptomatic participants and those with non-allergic rhinitis alone were mostly non-sensitized (around 72%) while around 12% were polysensitized. Between 32 and 43% of participants with allergic rhinitis alone, asthma alone and asthma+non-allergic rhinitis were non-sensitized and between 37 and 46% of them were polysensitized. 65% of the participants with asthma+allergic rhinitis were polysensitized. The level of total IgE followed a similar trend to that of allergic sensitization. Eosinophils were increased in asthma, especially when associated with rhinitis. Nasal symptoms were more severe and eczema more common in participants with both asthma and allergic rhinitis than in the other groups.
Conclusions
Allergic sensitization and particularly polysensitization rates widely differ according to asthma and rhinitis status. This study emphasized the importance of taking into account multimorbidity between asthma and rhinitis and showed that allergic sensitization is not a dichotomic variable.
This article is protected by copyright. All rights reserved.
http://ift.tt/2llCahv
The sensitization pattern differs according to rhinitis and asthma multimorbidity in adults: the EGEA study
Abstract
Background
Mono- and polysensitization are different IgE-mediated allergic phenotypes in children. Allergic sensitization is associated with both allergic asthma and allergic rhinitis, however, associations between the sensitization pattern and particularly polysensitization with asthma and rhinitis remains poorly studied in adults.
Aim
The aim of this study was to assess how the allergic sensitization pattern associates with asthma, rhinitis and their multimorbidity.
Methods
1,199 adults from the EGEA study, with extensive phenotypic characterization and all data available on skin prick tests to 10 allergens, total IgE and blood eosinophils were included. Using questionnaires only, participants were classified into 6 groups: asymptomatic (no asthma, no rhinitis), non-allergic rhinitis alone, allergic rhinitis alone, asthma alone, asthma+non-allergic rhinitis and asthma+allergic rhinitis. Mono- and polysensitization were defined by a positive skin prick test to one or more than one allergen respectively.
Results
Asymptomatic participants and those with non-allergic rhinitis alone were mostly non-sensitized (around 72%) while around 12% were polysensitized. Between 32 and 43% of participants with allergic rhinitis alone, asthma alone and asthma+non-allergic rhinitis were non-sensitized and between 37 and 46% of them were polysensitized. 65% of the participants with asthma+allergic rhinitis were polysensitized. The level of total IgE followed a similar trend to that of allergic sensitization. Eosinophils were increased in asthma, especially when associated with rhinitis. Nasal symptoms were more severe and eczema more common in participants with both asthma and allergic rhinitis than in the other groups.
Conclusions
Allergic sensitization and particularly polysensitization rates widely differ according to asthma and rhinitis status. This study emphasized the importance of taking into account multimorbidity between asthma and rhinitis and showed that allergic sensitization is not a dichotomic variable.
This article is protected by copyright. All rights reserved.
http://ift.tt/2llCahv
Recovery from desensitization of IgE-dependent responses in human lung mast cells
Abstract
Background
Clinical desensitization and oral food immunotherapy are therapeutic interventions that allow individuals who react adversely to an allergen (drug or food) to be made tolerant to the allergen. However, tolerance is brief and allergen hypersensitivity can recur within days following allergen withdrawal.
Objective
We hypothesize that the reason these treatments are temporary reflects rapid recovery of mast cells from a desensitized state. We sought to test this.
Methods
Desensitization of IgE-mediated histamine release from human lung mast cells was explored by methods that partially replicate the pattern of treatment during clinical desensitization. Specific and nonspecific desensitization and changes in surface IgE were examined following desensitization. Recovery from desensitization was also studied.
Results
Desensitization of mast cell responses was readily induced with concentrations of antigen or anti-IgE that were suboptimal for secretion. There was little or no nonspecific desensitization when lung mast cells were exposed to antigens. There was no loss of cell surface IgE following desensitization. Removing the desensitizing stimulus from the media following desensitization allowed the cells to recover with half-point of recovery of ~1.5 days and complete recovery after 5 days. Both the functional response and histamine content recovered within this timeframe. The recovery appeared possible because both antigens and anti-IgE dissociated rapidly from cells after washing to remove excess stimulus.
Conclusion and Clinical Relevance
Human lung mast cells readily recover from a desensitized state following removal of desensitizing antigen. This finding provides a potential explanation for the ephemeral nature of clinical desensitization.
This article is protected by copyright. All rights reserved.
http://ift.tt/2lH7EBA
Recovery from desensitization of IgE-dependent responses in human lung mast cells
Abstract
Background
Clinical desensitization and oral food immunotherapy are therapeutic interventions that allow individuals who react adversely to an allergen (drug or food) to be made tolerant to the allergen. However, tolerance is brief and allergen hypersensitivity can recur within days following allergen withdrawal.
Objective
We hypothesize that the reason these treatments are temporary reflects rapid recovery of mast cells from a desensitized state. We sought to test this.
Methods
Desensitization of IgE-mediated histamine release from human lung mast cells was explored by methods that partially replicate the pattern of treatment during clinical desensitization. Specific and nonspecific desensitization and changes in surface IgE were examined following desensitization. Recovery from desensitization was also studied.
Results
Desensitization of mast cell responses was readily induced with concentrations of antigen or anti-IgE that were suboptimal for secretion. There was little or no nonspecific desensitization when lung mast cells were exposed to antigens. There was no loss of cell surface IgE following desensitization. Removing the desensitizing stimulus from the media following desensitization allowed the cells to recover with half-point of recovery of ~1.5 days and complete recovery after 5 days. Both the functional response and histamine content recovered within this timeframe. The recovery appeared possible because both antigens and anti-IgE dissociated rapidly from cells after washing to remove excess stimulus.
Conclusion and Clinical Relevance
Human lung mast cells readily recover from a desensitized state following removal of desensitizing antigen. This finding provides a potential explanation for the ephemeral nature of clinical desensitization.
This article is protected by copyright. All rights reserved.
http://ift.tt/2lH7EBA
Specificity protein 1: Its Role in Colorectal Cancer Progression and Metastasis
Publication date: Available online 24 February 2017
Source:Critical Reviews in Oncology/Hematology
Author(s): Richa Bajpai, Ganji Purnachandra Nagaraju
Specificity protein 1 (Sp1) is a widely expressed transcription factor that plays an important role in the promotion of oncogenes required for tumor survival, progression and metastasis. Sp1 is highly expressed in several cancers including colorectal cancer (CRC) and is related to poor prognosis. Therefore, targeting Sp1 is a rational for CRC therapy. In this review, we will recapitulate the current understanding of Sp1 signaling, its molecular mechanisms, and its potential involvement in CRC growth, progression and metastasis. We will also discuss the current therapeutic drugs for CRC and their mechanism of action via Sp1.
http://ift.tt/2lE4xu0
Associations between trace elements and clinical health parameters in the North Pacific loggerhead sea turtle ( Caretta caretta ) from Baja California Sur, Mexico
Abstract
This study investigated selected trace elements toxicity in sea turtles Caretta caretta population from Baja California Sur (BCS), Mexico, by analyzing associations among Zn, Se, Cu, As, Cd, Ni, Mn, Pb, and Hg with various biochemical parameters (packed cell volume, leukocytes, and selected blood parameters), and whether their concentrations could have an impact on the health status of sea turtles. Blood samples from 22 loggerhead (C. caretta) sea turtles from BCS, Mexico, were collected for trace elements on biochemistry parameter analyses. Significant associations among trace element levels and the biochemistry parameters were found: Cd vs ALP (R 2 = 0.874, p ˂ 0.001), As vs ALP (R 2 = 0.656, p ˂ 0.001), Mn vs ALP (R 2 = 0.834, p ˂ 0.001), and Ni vs LDH (R 2 = 0.587, p ˂ 0.001). This study is the first report of the biochemical parameters of the North Pacific loggerhead sea turtle (C. caretta) from Baja California Sur, Mexico, and it is the first to observe several associations with toxic and essential trace elements. Our study reinforces the usefulness of blood for the monitoring of the levels of contaminating elements and the results suggest that, based on the associations with health clinical parameters, high levels of Cd and As could be representing a risk to the North Pacific loggerhead population health.
http://ift.tt/2kXqfKW
Ear, nose and thorat disorders in pediatric patients at a rural hospital in Senegal
Source:International Journal of Pediatric Otorhinolaryngology, Volume 96
Author(s): Hady Tall, Fatoumata Yarie Bah, Timi Nasser, Aly Sambou, Bay Karim Diallo
IntroductionThe main health problems encountered in pediatric population in Senegal are low birth weigth malnutrition and infection. However, there is a lack of data on pediatric ENT diseases from west african population. This is no published data on any research work on pattern ENT pediatric done in Senegal. This study aimed at determining the pattern of common pediatric ENT diseases.Patients and methodsThis was a retrospective descriptive study involving review of medical record of patients aged 0–16 years who presented ENT diseases from April 2011 to May 2013 (2 years).Resultswithin the study period a total of 1329 children were seen. We found 696 children male and 633 female, sex ratio (M/F) is 1.1. Mean age of patients seen was 06 years. Nasal disorders (54,6%) were found to be the commonest group of ENT, followed by ear disorders (22,8%) thorat (22,7%). Hypertrophic adenoid (27,9%) allergic rhinitis (22,9%) and pharyngitis (17,7%) are the most common ENT problems in our pediatric population.ConclusionThe main health problems encountered in pediatric population in Senegal are low birth weigth malnutrition and infection. This study indicated hypertrophic adenoid (27,9%) allergic rhinitis (22,9%) and pharyngitis (17,7%) are the most common ENT problems in our pediatric population. However, this study can provide basic data for heath plan and future local research work.
http://ift.tt/2mpcUYO
Nephroprotective effect of Rudgea viburnoides (Cham.) Benth leaves on Gentamicin-Induced Nephrotoxicity in Rats
Publication date: Available online 24 February 2017
Source:Journal of Ethnopharmacology
Author(s): Pablinny Moreira Galdino, Layse Nunes Alexandre, Lílian Fernanda Pacheco, Ruy de Souza Lino Junior, José Realino de Paula, Gustavo Rodrigues Pedrino, Carlos Henrique Xavier, Patrícia Maria Ferreira
RelevanceRudgea viburnoides, popularly known as "congonha-de-bugre" or "erva de bugre", is used in folk medicine as hypotensive, blood depurative, anti-rheumatic, diuretic and in the treatment of kidney and bladder pain.AimBased on the popularly acclaimed nephron-protective effect of R. viburnoides, we investigated, using rats, the protective effect of this plant extract on gentamicin-induced kidney injury.Material and methodsUrinary volume, water and food intakes were assessed in adult male Wistar rats (naive or gentamicin-induced model of nephrotoxicity) treated with R. viburnoides extract. Also blood and kidney samples were collected for further laboratory and histological analyses.ResultsR. viburnoides leaves extract improved renal function. It also improved the renal function impairments caused by gentamicin-induced nephrotoxicity, as revealed by glomerular filtration rate, urine output and proteinuria.ConclusionR. viburnoides exert renoprotective effect, which may support its popular use for renal diseases treatment.
Graphical abstract
http://ift.tt/2mpcWA7
Ipomoea pes-caprae (L.) R. Br (Convolvulaceae) relieved nociception and inflammation in mice – A topical herbal medicine against effects due to cnidarian venom-skin contact
Publication date: 22 March 2017
Source:Journal of Ethnopharmacology, Volume 200
Author(s): Cristiane da Silva Barth, Hugo Guilherme Tolentino de Souza, Lilian W. Rocha, Gislaine Francieli da Silva, Mariana Ferreira dos Anjos, Veronica D'Avila Pastor, Tania Mari Belle Bresolin, Angelica Garcia Couto, José Roberto Santin, Nara Lins Meira Quintão
Ethnopharmacological relevanceIpomoea pes-caprae is known as bayhops, beach morning glory or goat's foot, and in Brazil as salsa-de-praia. Its leaves are used in worldwide folk medicine for the relief of jellyfish-stings symptoms. The literature only reports the neutralizing effects of nonpolar plant derived over jellyfish venoms, without validating the popular use or exploring the mechanism of action.Aim of the studyThis study aimed to evaluate and validate the topical effects of a semisolid containing hydroethanolic extract obtained from the aerial parts of I. pes-caprae using different models of paw- and ear-oedema and spontaneous nociception in mice, attempting to better understand the mechanism involved in its effect.Materials and methodsLeaf and stem of I. pes-caprae were extracted by ethanol 50% (v/v) and the soft-extract was incorporated in Hostacerin® cream base at 0.5%, 1.0% and 2% (w/w). The anti-hypersensitivity effects were evaluated by injecting the Physalia physalis venom into the right mice's hindpaw pre-treated either with the semisolid containing the I. pes-caprae extract or with the isolated majority compound 3,5-Di-O-caffeoylquinic acid (ISA). The topical anti-inflammatory activity was investigated using both preclinical models: paw oedema induced by trypsin, bradykinin (BK), histamine and carrageenan, and ear oedema induced by capsaicin. Additionally, the model of spontaneous nociception induced by trypsin and capsaicin were used to verify the topical antinociceptive activity.ResultsThe animals pre-treated with the semisolid containing I. pes-caprae extract or with the intraplantar injection of the major component (ISA) had the mechanical hypersensitivity induced by P. physalis venom significantly reduced. Significant inhibition was also observed in paw-oedema induced by trypsin, histamine and BK, and in a less extent in carrageenan-induced paw oedema. Similar effect was observed in mice challenged to the capsaicin-induced ear-oedema. Besides the vascular effects, the extract interfered with leukocyte migration induced by histamine injection. Finally, the semisolid presented significant inhibition in trypsin- and capsaicin-induced spontaneous nociception.ConclusionsThe hydroethanolic extract of I. pes-caprae showed compliance with the topical popular use of the herbal product to relieve the symptoms evoked by the cnidarian venom-skin contact, such as neurogenic oedema and nociception. The extract components seem to interfere with the effects resulting from the TRPV1, B2R and PAR-2 activation, once it interfered with painful-behaviour and oedema induced by capsaicin, BK and trypsin, pointing the histaminergic system as the main target, once it is an important mediator in the signalling pathway of the aforementioned receptors.
Graphical abstract
http://ift.tt/2llfezg
Salvia miltiorrhiza polysaccharide activates T Lymphocytes of cancer patients through activation of TLRs mediated -MAPK and -NF-κB signaling pathways
Publication date: 22 March 2017
Source:Journal of Ethnopharmacology, Volume 200
Author(s): Yanan Chen, Haifeng Li, Meifeng Li, Shubin Niu, Jiaxin Wang, Hongwei Shao, Ting Li, Hui Wang
Ethnopharmacological relevanceSalvia miltiorrhiza polysaccharide (SMP) is one of the most important components in the water extract of Salvia miltiorrhiza Bunge, which has been mainly applied for the prevention or treatment of ischemic encephalopathy and cardiac diseases including myocardial infarction and coronary heart diseases in clinical practice.Aim of the studyOur object is to investigate the immune regulation effects of SMP, specifically on the proliferation and cytotoxicity of T lymphocytes through MAPK and NF-κB pathway in peripheral blood of cancer patients.Materials and methodsSMP was prepared through refluxing with ethanol, refluxing with water, Sevage treatment and ethanol precipitation. The lymphocytes were obtained from the peripheral blood of cancer patients. The effect of SMP on T lymphocyte proliferation was investigated by cell counting and flow cytometry. The effect of SMP on the proliferation of cancer cell lines A549, hepG2 and HCT116 was examined by MTT assay. The cytotoxic activity of T lymphocytes treated with SMP was detected by Calcein-acetoxymethyl (Calcein-AM) release. The gene expression of IL-4, IL-6, IFN-γ and toll like receptors (TLRs) was detected by semi-quantitative PCR. The protein expression of mitogen activated protein kinase (MAPK) and nuclear factor kappa-B (NF-κB) signaling pathway were detected by western blotting. To further verify whether SMP functions through the indicated pathways,, T lymphocytes were treated with SMP and an extracellular regulated protein kinase (ERK) inhibitor (U0126), a c-Jun N-terminal kinase (JNK) inhibitor (SP600125) or an inhibitor of NF-κB inhibitor-α (IκBα) (BAY11-7082), respectively. After 24 h co-treatment, the expressions of p-JNK, p-ERK, IκBα, inhibitory kappa B kinase α (IKKα) and inhibitory kappa B kinase β (IKKβ) protein were detected by western blotting, meanwhile cell numbers of T lymphocytes after inhibition were calculated again by cell counter.ResultsSMP dose-dependently promoted the proliferation of T lymphocytes of the cancer patients and significantly improved the cytotoxicity of T lymphocytes against cancer cells. However, SMP showed no effect on the proliferation of the tumor cells from the same source. Furthermore, the gene expression of cytokines including IL-4, IL-6 and IFN-γ were also up-regulated. Moreover, SMP enhanced gene expression of TLR1, TLR2 and TLR4; elevated protein expression of p-JNK and p-ERK; increased protein expression of IKKα, and IKKβ and decreased IκBα levels. Meanwhile, knockdown of ERK、JNK or IκBα expression with specific inhibitor significantly depressed the proliferation of T lymphocytes treated with SMP, corroborating the specific regulation effect of SMP on T lymphocytes through MAPK and NF-κB signaling pathways.ConclusionSMP specifically promotes the proliferation and enhances cytotoxicity of T lymphocytes in peripheral blood of cancer patients through activation of TLRs mediated -MAPK and -NF-κB signaling pathways.
Graphical abstract
http://ift.tt/2mpbNbr
Effects of the ethanol extract of black mulberry (Morus nigra L.) fruit on experimental atherosclerosis in rats
Publication date: Available online 24 February 2017
Source:Journal of Ethnopharmacology
Author(s): Yan Jiang, Min Dai, Wen-Jing Nie, Xiao-Rong Yang, Xian-Chun Zeng
Ethnopharmacological relevanceAtherosclerosis (AS) is the major pathogenic component of coronary artery and cardiovascular disease. Studies have increasingly focused on natural medicines that have lipid-lowering, anti-inflammatory, and endothelial–protection activities. Black mulberry fruits are traditionally used in Uyghur folk medicine for the prevention and treatment of cardiovascular diseases in southern Xinjiang region of China. However, its underlying mechanisms remain unknown. Thus, our objective was to explore the effects and underlying mechanisms of ethanol extract of black mulberry (EEBM) in experimental atherosclerotic rats.Materials and methodsThe black mulberry fruit was extracted with acid ethanol and chromatographed on an AB-8 macroporous resin to obtain EEBM. Atherosclerotic rats were divided into five groups: normal, model, model plus simvastatin (5mg/kg·d·body weight), and model plus low-dose and high-dose EEBM groups (105 and 210mg/kg·d·body weight, respectively). Serum lipid profiles were measured by an automatic biochemistry analyser. The activities of anti-oxidative enzymes were determined using the chemical colorimetric method. Pathological changes in liver and arteries were examined by hematoxylin and eosin (H&E), and the intima-media thickness was measured.ResultsThe high-dose EEBM group showed significantly reduced total cholesterol, triglyceride, and low-density lipoprotein-cholesterol levels, as well as atherogenic index. Furthermore, treatment with high-dose EEBM markedly decreased malondialdehyde content and enhanced anti-oxidative enzyme activities. Histopathological examination showed that EEBM attenuated hepatic steatosis and reduced intima-media thickness and arterial atherosclerotic lesions in atherosclerotic rats. These results suggest that EEBM suppressed atherosclerosis development in atherosclerotic rats by regulating lipid metabolism abnormalities, enhancing anti-oxidative activities, and reducing atherosclerotic lesions, which could be attributed to anthocyanins (23.75%), or the cooperative action of anthocyanins, polyphenols (2.95%), and flavonoids (0.94%).
Graphical abstract
http://ift.tt/2mp5q7Y
Analgesic and anti-inflammatory activities of 80% methanol root extract of Jasminum abyssinicum Hochst. ex. Dc. (Oleaceae) in mice
Publication date: Available online 24 February 2017
Source:Journal of Ethnopharmacology
Author(s): Yohannes Tadiwos, Teshome Nedi, Ephrem Engidawork
BackgroundPain and inflammation are associated with the pathophysiology of various clinical conditions. Most analgesic and anti-inflammatory drugs available in the market present a wide range of problems. The current study was aimed at investigating the analgesic and anti-inflammatory activity of 80% methanol extract of J.abyssinicum root.MethodsThe analgesic activity was determined using tail-flick test and acetic acid induced writhing, whereas anti-inflammatory activity was determined by carrageenan induced paw edema and formalin induced pedal edema, carried out in vivo. The test group received three different doses of the extract (50mg/kg, 100mg/kg and 200mg/kg) orally. The positive control group received diclofenac (10mg/kg), aspirin (100mg/kg or 150mg/kg) or morphine (20mg/kg) orally. The negative control group received vehicle (2% Tween 80, 10ml/kg) orally. Furthermore, preliminary phytochemical screening was carried out.ResultsOral administration of J.abbysinicum 80% methanol extract (at all doses) significantly (p < 0.001) inhibit pain sensation in the pain models. Similarly, the extract demonstrated anti-inflammatory effect in the inflammation models in mice. Preliminary phytochemical screening showed the presence of saponins, flavonoids, terepenoids, triterpenens and glycosides.ConclusionThe data obtained from the present study indicates that the extract possessed a significant analgesic and anti-inflammatory activity, upholding the folkloric use of the plant.
http://ift.tt/2mp0X5s
Editorial Board
Source:Clinical Therapeutics, Volume 39, Issue 2
http://ift.tt/2lloUcI
Table of Contents
Source:Clinical Therapeutics, Volume 39, Issue 2
http://ift.tt/2lGR2dg
Endothelial Notch1 Activity Facilitates Metastasis
Publication date: Available online 23 February 2017
Source:Cancer Cell
Author(s): Elfriede Wieland, Juan Rodriguez-Vita, Sven S. Liebler, Carolin Mogler, Iris Moll, Stefanie E. Herberich, Elisa Espinet, Esther Herpel, Amitai Menuchin, Jenny Chang-Claude, Michael Hoffmeister, Christoffer Gebhardt, Hermann Brenner, Andreas Trumpp, Christian W. Siebel, Markus Hecker, Jochen Utikal, David Sprinzak, Andreas Fischer
Endothelial cells (ECs) provide angiocrine factors orchestrating tumor progression. Here, we show that activated Notch1 receptors (N1ICD) are frequently observed in ECs of human carcinomas and melanoma, and in ECs of the pre-metastatic niche in mice. EC N1ICD expression in melanoma correlated with shorter progression-free survival. Sustained N1ICD activity induced EC senescence, expression of chemokines and the adhesion molecule VCAM1. This promoted neutrophil infiltration, tumor cell (TC) adhesion to the endothelium, intravasation, lung colonization, and postsurgical metastasis. Thus, sustained vascular Notch signaling facilitates metastasis by generating a senescent, pro-inflammatory endothelium. Consequently, treatment with Notch1 or VCAM1-blocking antibodies prevented Notch-driven metastasis, and genetic ablation of EC Notch signaling inhibited peritoneal neutrophil infiltration in an ovarian carcinoma mouse model.
Graphical abstract
Teaser
Wieland, Rodriguez-Vita et al. reveal that activated Notch1 signaling in endothelial cells (ECs) in tumors and in the pre-metastatic niche induces VCAM1 expression, leading to increased neutrophil infiltration and metastasis. Inhibition of Notch1 or VCAM1 reduces metastasis driven by EC Notch1 in mouse models.http://ift.tt/2lVhlNK
Psychological distress and parent reporting on child health: The case of developmental delay
Publication date: April 2017
Source:Research in Developmental Disabilities, Volume 63
Author(s): Scott Veldhuizen, Chloe Bedard, Christine Rodriguez, John Cairney
BackgroundCaregiver-completed screening questionnaires are a common first step in the identification of developmental delay. A caregiver's mood and anxiety level, however, may affect how he or she perceives and reports possible problems.AimsIn this article, we consider the association between caregiver distress and the accuracy of the Ages and Stages Questionnaire (ASQ), a widely-used screen.Methods and proceduresOur sample includes 857 parent-child dyads drawn from the Psychometric Assessment of the NDDS Study (PANS) and the NDDS Alternate Responses Study (NARS). Parents completed the ASQ and the K6, a brief measure of generalized distress. Children were assessed using the Bayley Scales of Infant and Child Development (BSID). We divided children on BSID result and used logistic regression to examine how distress influenced the ASQ's accuracy in each group.ResultsOf our 857 children, 9% had at least one domain below −2 standard deviations on the BSID, and 17.3% had positive ASQ results. Caregiver distress predicted a positive ASQ substantially and significantly more strongly among BSID-positive children than among others. This translates into slightly reduced ASQ specificity but greatly improved sensitivity among caregivers with higher distress.ConclusionsAt low to moderate levels of distress, greater distress is associated with greater ASQ accuracy.
http://ift.tt/2moRpaF
Resting energy expenditure in girls with Turner syndrome
Journal Name: Journal of Pediatric Endocrinology and Metabolism
Issue: Ahead of print
http://ift.tt/2moVVGd
Increased prevalence of bicuspid aortic valve in Turner syndrome links with karyotype: the crucial importance of detailed cardiovascular screening
Journal Name: Journal of Pediatric Endocrinology and Metabolism
Issue: Ahead of print
http://ift.tt/2lR4606
Assessment of health-related quality of life in Egyptian adolescents with type 1 diabetes: DEMPU survey
Journal Name: Journal of Pediatric Endocrinology and Metabolism
Issue: Ahead of print
http://ift.tt/2mi9rOZ
Risk of second primary cancer associated with pre-diagnostic smoking, alcohol, and obesity in women with keratinocyte carcinoma
Source:Cancer Epidemiology, Volume 47
Author(s): Sang Min Park, Tricia Li, Shaowei Wu, Wen-Qing Li, Abrar A. Qureshi, Meir Stampfer, Eunyoung Cho
Keratinocyte carcinoma (KC), which includes basal-cell carcinoma (BCC) and squamous-cell cancer (SCC), has been associated with an increased risk of second primary cancers (SPCs), although the reason for this increase is unknown. We assessed the effects of smoking, alcohol, and obesity prior to the diagnosis of KC on the development of SPCs, as these are well-established risk factors for multiple cancers and may also contribute to the increased risk of SPCs among those with KC. A total of 15,628 women with self-reported KC were identified in the Nurses' Health Study. Incident SPCs were assessed throughout the follow-up until June 2012. Cox proportional hazards models were used to calculate the hazard ratios (HRs) of SPC associated with pre-diagnostic smoking, alcohol and body mass index (BMI). We also compared these risk estimates to those for first cancers in all cohort participants. During 193,695 person-years of follow-up, we recorded 2839 SPC cases. Compared with never smokers, current smokers had a significantly elevated risk for SPC overall and specifically for lung, colorectal, and bladder cancers. We also found a positive association between higher BMI and risk for SPC overall as well as for endometrial and bladder SPCs. Women with KC who consumed alcohol ≥30g/day had a marginally higher risk of SPC compared to non-drinkers. The associations between incident SPC risk among KC cases and smoking, alcohol, and obesity appeared similar to the associations between these risk factors and the incident first primary cancers in the whole cohort. Only in the heavy smoking (≥25 cigarettes/day) category was the HR for SPC after KC (2.34; 95% CI 1.98–2.76) slightly higher than that for the first cancer in the overall cohort (HR 1.86; 95% CI 1.75–1.98, Pheterogeneity=0.01). In conclusion, pre-diagnostic smoking, alcohol and obesity prior to KC diagnosis were associated with risk of SPCs.
http://ift.tt/2mwpsN4
Intermittent entrapment of choroid plexus in ventricular catheter
Publication date: September 2017
Source:Interdisciplinary Neurosurgery, Volume 9
Author(s): Guanxiong Mao, Nitin Agarwal, Giulio Zuccoli, Elizabeth C. Tyler-Kabara
Ventriculoperitoneal (VP) shunt placement remains the primary treatment option for most cases of pediatric hydrocephalus. However, these devices have a relatively high complication with malfunction commonly attributed to proximal catheter occlusion. Factors augmenting shunt malfunction include infection, valve failure, proximal or distal catheter obstruction, distal catheter migration, shunt disconnection. In this case report, we describe the perioperative course of a neonate with communicating hydrocephalus who required a VP shunt, with real time sonographic documentation of the transient occlusion of the ventricular catheter tip by choroid plexus immediately after surgery.
http://ift.tt/2kWJ80y
Polysubstance use in treatment seekers who inject amphetamine: Drug use profiles, injecting practices and quality of life
Source:Addictive Behaviors, Volume 71
Author(s): Peter J. Kelly, Laura D. Robinson, Amanda L. Baker, Frank P. Deane, Rebecca McKetin, Suzie Hudson, Carol Keane
BackgroundThe injection of amphetamine is becoming increasingly common. However, there has been a lack of research examining people who inject amphetamine as the primary drug of use, limiting the potential to ensure services address the unique needs of this group. The current study used latent class analysis to identify classes of polydrug use among people who report injecting amphetamine during the past 12months. It also examined differences between classes and drug use patterns, injecting practices, quality of life and psychological distress.MethodsParticipants who were attending non-government specialist alcohol and other drug treatment across New South Wales, Australia and had identified amphetamine as their principle drug of concern and reported injecting amphetamine in the previous 12months were included in the current study (N=827). Latent class analysis was performed to identify polydrug profiles of participants.ResultsThe large majority of people in the current study (85%) demonstrated low probability of heroin or other opiate use. Three distinct classes of polydrug use were identified: (1) Low-polydrug (n=491), (2) Opiates-polydrug (n=123), and (3) Alcohol-polydrug (n=213). There was a trend for the Low-polydrug class to demonstrate better functioning and safer injecting practices than the Opiates-polydrug and Alcohol-polydrug classes.ConclusionThe results suggest that the majority of people accessing treatment who inject amphetamine as their primary drug of choice have a low probability of heroin or other opiate use. It is important that future research consider whether traditional harm minimisation strategies are appropriate for people who primarily inject amphetamine.
http://ift.tt/2lGxbcm
Perceived risk and benefits of e-cigarette use among college students
Source:Addictive Behaviors, Volume 71
Author(s): Amy L. Copeland, MacKenzie R. Peltier, Krystal Waldo
Recent data demonstrates that the use of e-cigarettes is growing, especially among college students and young adults. This trend is increasingly problematic, as many of these individuals report never using traditional tobacco cigarettes, but nevertheless are using e-cigarettes. The present study sought to develop the Risks and Benefits of E-cigarettes (RABE) questionnaire to assess the perceptions about e-cigarette use among college students. College students (N=734) completed the RABE via online survey. Principal components analysis yielded two reliable scales representing perceptions about e-cigarette use. Based on the two-factor solution, subscales were named according to item content. The resulting 30 items demonstrated excellent internal consistency (Risks scale α=0.92; Benefits scale α=0.89). Subsequent confirmatory factor analysis generally supported the 2-factor structure. As an initial measure of construct validity, scale scores were compared across smoking status groups. Smoking status groups were defined by the following: "e-cigarette users" were current daily users of e-cigarettes, "conventional smokers" were daily traditional cigarette users, and "dual users" were individuals who used both e-cigarettes and traditional cigarettes daily. Scale scores for perceived Benefits of e-cigarette use differed significantly across groups (p<0.001), whereby students who reported using e-cigarettes or traditional cigarettes reported benefits associated with e-cigarette use. Scale scores for perceived Risks of e-cigarette use across smoking status groups did not significantly differ. The present results indicate that the RABE is a reliable instrument to measure college student's perceived risks and benefits of e-cigarettes.
http://ift.tt/2lUVs0V
Conjugation of PEG-hexadecane markedly increases the immunogenicity of pneumococcal polysaccharide conjugate vaccine
Source:Vaccine
Author(s): Xin Chang, Weili Yu, Shaoyang Ji, Lijuan Shen, Aijuan Tan, Tao Hu
Streptococcus pneumoniae is a serious Gram-positive pathogen that can lead to an invasive pneumococcal disease with high mortality rate. Pneumococcal capsular polysaccharide (PS) is a key virulence determinant and its immunogenicity can be increased by conjugation with a carrier protein. However, the PS-specific cellular and humoral immunity of pneumococcal conjugate vaccine needs further improvement. Hexadecane (HD) is an element of lipid that decorates the surface of nearly all microbial classes. Polyethylene glycol (PEG)-HD conjugate (PEG-HD) is soluble and can act as an adjuvant. In the present study, a novel pneumococcal polysaccharide conjugate vaccine was prepared by conjugation of tetanus toxoid (TT) portion of PS-TT conjugate (PS-TT) with PEG-HD. As compared with PS-TT, conjugation with PEG-HD led to an 8.0-fold increase in the PS-specific IgG titers. Conjugation with PEG-HD also gave rise to 34.9-, 3.6- and 7.7-fold increase in the IFN-γ, TNF-α and IL-5 levels, respectively. Thus, the conjugated PEG-HD has a stimulatory adjuvant activity to potentiate a robust humoral and cellular immunity. Our proposed conjugate was expected to act as an effective pneumococcal conjugate vaccine for prevention of S. pneumoniae infections.
http://ift.tt/2lGxmnV
Interplay between SIRT1 and hepatitis B virus X protein in the activation of viral transcription
Publication date: Available online 24 February 2017
Source:Biochimica et Biophysica Acta (BBA) - Gene Regulatory Mechanisms
Author(s): Jian-Jun Deng, Ka-Yiu Edwin Kong, Wei-Wei Gao, Hei-Man Vincent Tang, Vidyanath Chaudhary, Yun Cheng, Jie Zhou, Chi-Ping Chan, Danny Ka-Ho Wong, Man-Fung Yuen, Dong-Yan Jin
Hepatitis B virus (HBV) genome is organized into a minichromosome known as covalently closed circular DNA (cccDNA), which serves as the template for all viral transcripts. SIRT1 is an NAD+-dependent protein deacetylase which activates HBV transcription by promoting the activity of cellular transcription factors and coactivators. How SIRT1 and viral transactivator X protein (HBx) might affect each other remains to be clarified. In this study we show synergy and mutual dependence between SIRT1 and HBx in the activation of HBV transcription. All human sirtuins SIRT1 through SIRT7 activated HBV gene expression. The steady-state levels of SIRT1 protein were elevated in HBV-infected liver tissues and HBV-replicating hepatoma cells. SIRT1 interacted with HBx and potentiated HBx transcriptional activity on precore promoter and covalently closed circular DNA (cccDNA) likely through a deacetylase-independent mechanism, leading to more robust production of cccDNA, pregenomic RNA and surface antigen. SIRT1 and HBx proteins were more abundant when both were expressed. SIRT1 promoted the recruitment of HBx as well as cellular transcriptional factors and coactivators such as PGC-1α and FXRα to cccDNA. Depletion of SIRT1 suppressed HBx recruitment. On the other hand, SIRT1 recruitment to cccDNA was compromised when HBx was deficient. Whereas pharmaceutical agonists of SIRT1 such as resveratrol activated HBV transcription, small-molecule inhibitors of SIRT1 including sirtinol and Ex527 exhibited anti-HBV activity. Taken together, our findings revealed not only the interplay between SIRT1 and HBx in the activation of HBV transcription but also new strategies and compounds for developing antivirals against HBV.
http://ift.tt/2laMat9
Εγγραφή σε:
Αναρτήσεις (Atom)