Tracking the effect of emotional distraction in working memory brain networks: Evidence from an MEG study

Abstract

The active maintenance of information in visual working memory (WM) is known to rely on the sustained activity over functional networks including frontal, parietal, occipital, and temporal cortices. Previous studies have described interference-based disturbances in the functional coupling between prefrontal and posterior cortices, and that such disturbances can be restored for a successful WM performance after the presentation of the interfering stimulus. However, very few studies have applied functional connectivity measures to the analysis of the brain dynamics involved in overriding emotional distraction, and all of them have limited their analysis to the particular connections between the amygdala and prefrontal cortex. In this study, we used magnetoencephalography (MEG) to characterize the mutual information–based functional connectivity dynamics among regions of interest located over the prefrontal, the parietal, the temporal, and the occipital cortex. Our results show that the detection of emotional distraction at early latencies (50–150 ms) induces a reduction of functional connectivity involving parietal and temporal cortices that are part of the frontoposterior WM network, while functional coupling among prefrontal areas and between them and posterior cortices is strengthened during the detection of emotional distractors. Later in the processing of the distractor (250–350 and 360–460 ms), the frontoposterior coupling is reestablished for a successful performance, while the orbitofrontal and ventrolateral prefrontal cortex become strongly connected to posterior cortices as a mechanism to cope with emotional distractors.

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Eosinophilic Esophagitis in Children

Abstract

Purpose of Review

EoE is a significant cause of gastrointestinal morbidity affecting 1:2000. Patients with EoE typically have multiple atopic comorbidities, and additionally, many patients with EoE can be controlled well with elimination diets. The purpose of this review is to summarize the care of pediatric eosinophilic esophagitis patients.

Recent Findings

EoE represents a distinct clinical syndrome which is characterized by esophageal dysfunction and eosinophil-predominant inflammation of the esophageal mucosa. Patients with EoE can present with varying symptoms depending on their age; in this review, we review the presenting features of eosinophilic esophagitis in children as well as a diagnostic algorithm for EoE. The mucosal inflammation in EoE is driven by exposure to food antigens in many patients with EoE. Therefore, for the majority of patients, the mainstays of treatment remain food elimination diets or swallowed steroids.

Summary

This review summarizes the diagnostic approach to eosinophilic esophagitis (EoE) in pediatric patients, focusing on the importance of accurate diagnosis and selection of appropriate therapy.

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Ternary NixCo3-xS4 with Fine Hollow Nanostructure as Robust Electrocatalyst for Hydrogen Evolution

Elaborate design of efficient and stable electrocatalysts from earth-abundant elements to replace precious Pt for the hydrogen evolution reaction (HER) is an ongoing challenge. Doping metallic compounds with additional metal atoms provides the opportunity to tune their electronic and crystal structures, thus ameliorating their electrocatalytic properties. Here, we report for the first time a robust and earth-abundant Ni-doped Co3S4 catalyst grown on carbon cloth that showed high HER activity in 1 M KOH. The morphology evolution and HER activity are strongly related to the Ni substitution ratio. Electrochemical tests showed a low overpotential of 72.82 mV at 10 mA*cm-2, small Tafel slope of 49.44 mV*dec-1, and long-term durability over 46 h HER operation for the Ni0.5Co2.5S4 nanotube array self-standing on carbon cloth. These data indicate that atomic modulation of Ni plays an important role in optimizing the morphology and electrocatalytic activity by greatly expanding the active sites in the electrocatalyst. Further, the 3D self-standing nanotube array highly aids the exposure of active species and transfer of electrons and charges, substantially boosting the reaction kinetics and structure stability.

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Secondary Impact of Manganese on Catalytic Property of N-Doped Graphene in the Hydrogen Evolution Reaction

Catalysts play a key role in hydrogen production, as a green energy carrier. We have shown for the first time that manganese impurities in graphene can improve the catalytic activity of synthesized N-doped graphene (NG) for the hydrogen evolution reaction in acid media via influencing the ratio of different N-functionalities. This results in a 122 mV improvement in the over-potential following Mn impregnation of graphene. Transmission electron microscopy images confirmed the formation of manganese oxide nanoparticles on NG sheets. X-ray photoelectron spectroscopy revealed structural alteration in favour of higher quantities of quaternary and pyrrolic nitrogen functionalities, from approximately 37% in NG to 84% in Mn-inserted-doped graphene catalyst. This enhanced catalytic performance, based on density functional theory (DFT) calculations in the literature, is attributed to an increase in the number of active sites with higher activity.

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Excellent selectivity with high conversion in semi-hydrogenation of alkynes using Pd-based bimetallic catalysts

A series of active carbon supported PdPb and PdCu bimetal catalysts for selective semi-hydrogenation of alkynes with excellent selectivity and stability in liquid-phase. Pd0.33Pb0.67/C catalyst showed the best performance for various alkynes under mild reaction conditions (room temperature and ambient H2 pressure), showing 100% conversion and 98% selectivity to alkenes. Particularly, over hydrogenation was avoided under complete alkyne conversion.

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First Neutral and Cationic Tungsten Imido Alkylidene N-Heterocyclic Carbene Complexes

Abstract

The synthesis of W(NAr′)(NHC)(=CHR)(2,5-Me₂pyr)₂ (1; Ar′: 2,6-iPr₂C₆H₃; NHC: 1,3-diisopropylimidazol-2-ylidene; 2,5-Me₂pyr: 2,5-dimethylpyrrolide; R: CMe₂Ph), W(NAr′)(NHC)(=CHR)(2,5-Me₂pyr)(OC₆F₅) (2), W(NAr′)(NHC)(=CHR)(OSiPh₃)₂ (3), [W(NAr′)(NHC)(=CHR)(OSiPh₃))(MeCN)⁺][B(Ar^F)₄⁻] (4; B(Ar^F)₄⁻: B(3,5-(CF₃)₂C₆H₃)₄⁻), [W(NAr′)(NHC)(=CHR)(2,5-Me₂pyr))⁺][B(Ar^F)₄⁻] (5), [W(NAr′)(NHC)(=CHR)(OC₆F₅))(tBuCN)⁺][B(Ar^F)₄⁻] (6), W(NAr′)(NHC)(=CHR)(OtBu)₂ (7), [W(NAr′)(NHC)(=CHR)(OtBu)⁺][B(Ar^F)₄⁻] (8), and W(NAr′)(NHC)(=CHR)(OCMe(CF₃)₂)₂ (9) is described, and the reactivity of the complexes in olefin metathesis and cyclopolymerization is reported. The cationic complexes 4, 5, and 6 showed high productivity and activity in olefin metathesis reactions, with turnover numbers of up to 40 000 and turnover frequencies (TOF_5min) of up to 31 s⁻¹, and also substantial functional group tolerance toward esters, nitriles, alcohols, and sulfides, particularly in the cyclopolymerization of α,ω-diynes.

Tolerance is complex: High productivity and activity in olefin metathesis reactions, along with substantial functional group tolerance, was shown by cationic tungsten imido alkylidene N-heterocyclic carbene complexes.

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Hierarchical Ti-beta obtained by simultaneous desilication and titanation as efficient catalyst for cyclooctene epoxidation

A novel postsynthesis route to hierarchical Ti beta zeolite and its performance as efficient catalyst in heterogeneous cyclooctene epoxidation are presented. Catalytically active Ti-sites as well as meso- and macropores are simultaneously introduced into microporous beta zeolite by hydrothermal treatment using tetrabutyl orthotitanate as titanation agent and tetraethylammonium hydroxide as desilication base. Simultaneous desilication and titanation (SDT) offers the advantages of reduced experimental effort and chemical waste. The possibility to use a commercial zeolite available in high quantity as starting material is attractive for industrialization. A significant mesopore volume (Vmeso = 0.19 cm³ g 1) was introduced in the resulting hierarchical Ti beta zeolite without loss of microporosity and crystallinity compared to the purely microporous counterpart. The comparison clearly demonstrates a higher catalytic activity for the hierarchical Ti-beta in cyclooctene epoxidation and accelerated desorption kinetics associated with the highly interconnected pore system.

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Electrocatalytic Properties of Cuprous Delafossite Oxides for Alkaline Oxygen Reduction Reaction

Inspired by the oxygen-binding copper sites in biomolecules, a series of cuprous delafossite oxides (CuBO2, B = Sc, Y, La) with similar interatomic copper distances were utilized as electrocatalysts for the oxygen reduction reaction (ORR). The carbon-supported oxides showed improved onset potential, current, and electron transfer number over carbon black, with CuLaO2 having the highest prevalence of the complete four electron reduction. The oxygen electrocatalytic activity of the copper-site in delafossite oxides was demonstrated.

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On the role of acidity in bulk and nanosheet [T]MFI (T = Al3+, Ga3+, Fe3+, B3+) zeolites in the methanol-to-hydrocarbons reaction

The influence of framework substituent (Al3+, Ga3+, Fe3+ and B3+) and morphology (bulk vs. nanometer-sized sheets) of MFI zeolite on acidity and catalytic performance in the methanol-to-hydrocarbons (MTH) reaction was investigated. The Brønsted acid density and strength decreased in the order Al(OH)Si > Ga(OH)Si > Fe(OH)Si >> B(OH)Si. Pyridine-15N NMR spectra confirmed differences in the Brønsted and Lewis acid strengths but also evidenced site heterogeneity in the Brønsted acid sites. Due to the lower efficiency with which tervalent ions can be inserted into the zeolite framework, sheet-like zeolites exhibited lower acidity than bulk zeolites. The sheet-like Al-containing MFI zeolite exhibited the greatest longevity as MTH catalyst, outperforming its bulk [Al]MFI counterpart. While the lower acidity of bulk [Ga]MFI led to better catalytic performance than bulk [Al]MFI, the sheet-like [Ga]MFI sample was found to be nearly inactive due to lower and heterogeneous Brønsted acidity. All Fe- and B-substituted zeolite samples displayed very low catalytic performance due to their weak acidity. Based on product distribution, the MTH reaction was found to be dominated by the olefins-based catalytic cycle. The small contribution of the aromatics-based catalytic cycle was larger for bulk zeolite than for sheet-like zeolite, indicating that shorter residence time of aromatics can explain the lower tendency to coking and enhanced catalyst longevity.

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Improving carbon coated TiO2 films with a TiCl4 treatment for photocatalytic water purification

Using a simple thermal decomposition route, carbon-TiO2 hybrid films have been synthesized from a catechol-TiO2 surface complex. The coated films display enhanced visible region absorption, owing to the thin (~2 nm) layer of carbon encapsulating the TiO2. While photocatalytically active under visible light alone, it is demonstrated that the activity of the carbon coated films can be improved further by a hydrolytic treatment with TiCl4, leading to the introduction of small TiO2 particles (5-10nm) and doping of chlorine into the structure. The combination of the carbon layer and TiCl4 treatment gives increased photocatalytic performance for the photodegradation of dyes, phenolic pollutants and the reduction of toxic Cr(VI) to relatively benign Cr(III). In addition, the carbon coated films show improved bactericidal activity under UV irradiation, and hence have been successfully tested against the most common types of pollutant present in potential drinking waters.

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PEGylation greatly enhances laccase polymerase activity

Laccase catalyzes the oxidation and polymerization of phenolic compounds in the presence of oxygen. Herein, we report for the first time that a previous pegylation of laccase enhances the polymerase activity by 3-fold comparing with the native enzyme, as confirmed by UV-Vis spectroscopy. The polymerization of catechol increased only 1.5-fold when polyethyleneglycol (PEG) was added to the medium reaction. Molecular dynamic simulations suggest the formation of a miscible complex of polycatechol and PEG, which is responsible to push the reaction forward. In a negative control experiment set, all catalysts were entrapped inside acrylamide gels and here the native laccase showed a relatively higher activity. These results suggest that the mobility of PEG is a key feature for the enhancement of the reaction.

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Access to (Hetero)arylated Selenophenes via Palladium-catalysed Stille, Negishi or Suzuki Couplings or C−H Bond Functionalization Reaction

Abstract

(Hetero)aryl-substituted selenophenes exhibit important physical properties especially for optoelectronics. Palladium-catalysed coupling reactions currently represent the most efficient methods to prepare such (hetero)arylated selenophene derivatives. Initially, Stille coupling was the most efficient reaction for the synthesis of these compounds; however, over the last decade, Suzuki coupling has become the most commonly employed. Recently, Pd-catalysed arylation via the C−H bond activation of selenophenes has proved to be a very convenient alternative method for the preparation of several arylated selenophenes as there is no need to prepare organometallic derivatives. In this Review, the progress and substrate scope in the synthesis of both C2- and C3-arylated selenophenes via Pd-catalysis are summarized.

Selenophenes stereotypes: The progress and substrate scope of the palladium catalyzed synthesis of both C2- and C3-arylated selenophenes are summarized in this Review—from Stille, Suzuki, and Negishi coupling through to C−H bond activation

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Hydrodeoxygenation of Phenol over Zirconia-Supported Catalysts: The Effect of Metal Type on Reaction Mechanism and Catalyst Deactivation

Abstract

This work aims at investigating the effect of the type of metal (Pt, Pd, Rh, Ru, Cu, Ni, Co) on the performance of ZrO₂-supported catalysts for the hydrodeoxygenation of phenol in the gas phase at 573 K and 1 atm. Two different reaction pathways take place depending on the type of the metal. For Pt/ZrO₂ and Pd/ZrO₂ catalysts, phenol is mainly tautomerized, followed by hydrogenation of the C=C bond of the tautomer intermediate formed, producing cyclohexanone and cyclohexanol. By contrast, the direct dehydroxylation of phenol followed by hydrogenolysis might also occur over more oxophilic metals such as Rh, Ru, Co, and Ni. In addition to the metals, the oxophilic sites of this support represented by Zr⁴⁺ and Zr³⁺ cations near the perimeter of the metal particles also increased the selectivity to deoxygenated products. All catalysts were significantly deactivated mainly owing to the growth of metal particle size and the decrease in the density of oxophilic sites.

Metal effects: The product distribution in the hydrodeoxygenation of phenol is investigated as a function of the type of the metal. Two different reaction pathways take place depending on the type of the metal in the ZrO₂-supported catalysts; phenol tautomerization, followed by hydrogenation of the C=C bond (Pt,Pd) and direct dehydroxylation of phenol followed by hydrogenolysis (Rh,Ru,Co,Ni).

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Auto-reduction Behaviour of Cobalt on Graphitic Carbon Nitride Coated Alumina Supports for Fischer-Tropsch Synthesis

The graphitic carbon nitride (g-C3N4)-coated alumina (CN-Al) is investigated as a support material for a cobalt-based Fischer-Tropsch synthesis (FTS) catalyst. The g-C3N4 blocks the interaction between cobalt and alumina to hinder the formation of irreducible cobalt oxide species, and improves the dispersion of metallic cobalt species on the CN-Al support. Furthermore, the coated g-C3N4 is decomposed during the pre-annealing process under inert condition to evolve reductive carbon monoxide gas that directly reduces the cobalt oxide species to metallic cobalt. Hence, the catalyst can be activated without typical hydrogen pretreatment. Moreover, the reduction promotion by expensive noble metals like Pt is not needed either. Because of the improved dispersion and reducibility of the cobalt species on CN-Al support, the catalytic FTS activity is higher compared to the conventional Co/Al2O3 catalyst.

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New Carbon Nanodots-Silica Hybrid Photocatalyst for Highly Selective Solar Fuel Production from CO2

Photocatalytic CO2 reduction for solar fuel production has attracted considerable attention as it can simultaneously reduce the effects of worldwide fossil-fuel shortage and global warming. As a means to achieve this we herein report the facile and eco-friendly synthesis of highly active carbon nanodots-silica hybrid photocatalyst (CNDSH) by a reverse microemulsion method with a nonionic surfactant. The photocatalyst-biocatalyst coupled system developed using CNDSH as photocatalyst functions efficiently to carry out high NADH regeneration (74.10 ± 0.17 %) followed by its consumption in exclusive formic acid production (203.33 ± 1.9 µmol) from CO2. This research work is a benchmark example of carbon nanodots-silica hybrid photocatalyst system for solar fuel production and expected to trigger further interest in the development of efficient and eco-friendly CO2 reduction systems.

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The French Conference on Catalysis—FCCat 1

Vive la catalyse française! From state-of-the-art model approaches to advanced characterization and kinetic studies, by materials and complexes synthesis or post-treatment, the systems showcased by this special issue in honor of French Catalysis are involved in natural gas and biomass conversion, pollutant mitigation, oxygen and hydrogen evolution reactions, to name a few.

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Cover Picture: The Pivotal Role of Catalysis in France: Selected Examples of Recent Advances and Future Prospects. (ChemCatChem 12/2017)

The Front Cover shows the potential of catalysis in France.In their Review, H. Olivier-Bourbigou et al. summarize the most significant breakthroughs reported in France over the last ten years in the field of heterogeneous catalysis. The Review focuses on the development of catalytic systems for specific applications, such as petrochemistry, biomass transformation, environmental applications and CO₂ for energy. The significant cross-disciplinary approaches, essential to understand and optimize catalytic processes, are also described. More information can be found in the Review by H. Olivier-Bourbigou et al. on page 2029 in Issue 12, 2017 (DOI: 10.1002/cctc.201700426).

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Cover Feature: Chemical Weathering of Alumina in Aqueous Suspension at Ambient Pressure: A Mechanistic Study (ChemCatChem 12/2017)

The Cover depicts the formation of surface mixed phases and Si grafting on the lateral facets of γ-alumina. In their Full Paper, J. Abi Aad et al. demonstrate that formation of surface mixed phases and Si grafting on the lateral facets of γ-alumina respectively inhibits and suppresses the alumina transformation to boehmite through a dissolution-precipitation process under hydrothermal conditions. More information can be found in the Full Paper by J. Abi Aad et al. on page 2186 in Issue 12, 2017 (DOI: 10.1002/cctc.201700140).

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Inside Cover: Facile Synthesis of Cu@CeO2 and Its Catalytic Behavior for the Hydrogenation of Methyl Acetate to Ethanol (ChemCatChem 12/2017)

The Cover shows a facile method to fabricate a Cu@CeO₂ catalyst that exhibits excellent activity and stability in the hydrogenation of methyl acetate.In their Communication, Y. Wang et al. demonstrate that the core–shell structure of Cu@CeO₂ not only prevents the aggregation of Cu particles but also enlarges the contact area between Cu and CeO₂, which greatly increases the Cu⁺ surface area. Moreover, the Cu⁰ and Cu⁺ active sites are well distributed on the core–shell interface, which results in a close relative position and an enhanced synergetic catalysis effect for the hydrogenation of methyl acetate. More information can be found in the Communication by Y. Wang et al. on page 2085 in Issue 12, 2017 (DOI: 10.1002/cctc.201700111).

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Back Cover: Biomass-assisted Zeolite Syntheses as a Tool for Designing New Acid Catalysts (ChemCatChem 12/2017)

The Cover shows an alternative route involving sugar cane-derived biomass to produce zeolites with tailored properties.In their Concept, B. Louis et al. highlight the impact of the presence of sugars, lignin, biomass hydrolysates and biomass residues on the crystallization of various zeolite structures. The presence of those biosourced secondary templates (BSST) induces morphological/textural changes and, sometimes, modifications of the chemical composition and acidic properties. The BSST strategy may serve as a basis for the rational synthesis of heterogeneous catalysts. More information can be found in the Concept by B. Louis et al. on page 2065 in Issue 12, 2017 (DOI: 10.1002/cctc.201700062).

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Inside Back Cover: Selective Oxidation of n-Butane and Isobutane Catalyzed by Boron Nitride (ChemCatChem 12/2017)

The Cover shows n-butane accompanied by an oxygen molecule traversing a boron nitride bridge. Upon crossing the bridge, n-butane is selectively transformed to 1-butene while another, less fortunate molecule falls over the cliff to become CO₂.In their Full Paper, J. M. Venegas et al. report that hexagonal boron nitride selectively catalyzes the oxidative dehydrogenation of n-butane and isobutane to their respective olefins. Boron nitride is unique in that overoxidation of the desired olefins to carbon oxides is kept to a minimum and instead the minor side-products are lighter olefins. The observed reaction kinetics point to a fundamentally different mechanism to that observed with conventional metal oxide catalysts. More information can be found in the Full Paper by J. M. Venegas et al. on page 2118 in Issue 12, 2017 (DOI: 10.1002/cctc.201601686).

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Oxidation of cyclohexene in the presence of transition metal substituted phosphotungstates and hydrogen peroxide: catalysis and reaction pathways

Homogeneous catalytic oxidations of cyclohexene by transition metal substituted phosphotungstates [PW₁₁M(L)O₃₉]m- (PW₁₁M, M = Co(II), Cu(II), Fe(III), Ni(II), Mn(II), L = H₂O or absence) with hydrogen peroxide in acetonitrile were experimentally studied. The catalytic activities of allylic oxidation were found to strongly depend on the transition metals, and PW₁₁Co showed the highest activity. The product distribution and the catalyst stability were dominated by mole ratio of hydrogen peroxide to PW₁₁M, whose low or high led to stable structure of PW₁₁M and predominant formation of allylic oxidation products or decomposition of PW₁₁M. Different from the activation of allylic C-H bond by radicals, the oxidation of C=C double bond was based on tungsten-peroxo species. A reaction mechanism composed of radical and non-radical processes was proposed from nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR) and kinetic data, to describe the reaction pathways of cyclohexene oxidation.

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Delays in breast cancer diagnosis after a state policy limiting Medicaid enrollment

In this issue of Cancer, Tarazi et al investigate the effects of a state policy that substantially limited Medicaid enrollment on the timeliness of breast cancer diagnosis. They observe a statistically significant increase of 3.3 percentage points in the percentage of women diagnosed with late-stage disease after the policy change among women living in low-income versus high-income areas. See also pages 000-000.

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Professional Ethics: Making the Right Decision

Professionals today are faced with many ethical dilemmas and it has become crucial for clinicians to understand how ethical decisions are made, what are the necessary considerations and how to apply each to the many ethical dilemmas they may face. This course will give an overview of the why’s and how’s to making an ethical decision and will provide the practitioner with a framework for exploring ethical dilemmas.

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Vanderbilt Audiology Journal Club - Research Examining Benefit of Hearing Aid Features

Dr. Todd Ricketts from Vanderbilt University discusses recent key journal articles regarding evidence for the benefits of select hearing aid features, and their implications for audiology clinical practice.

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BacterioFiles 299 - Predator Pops Polymer Producers

This episode: Using predatory bacteria to extract valuable bioplastics from other bacteria!

(6.3 MB, 6.9 minutes)

Show notes: 

N...

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Correction of dropped head deformity through combined anterior and posterior osteotomies to restore horizontal gaze and improve sagittal alignment

Abstract

Objective

The aim of this study is to present our technique for a large focal correction of a partially flexible dropped head deformity through combined anterior and posterior osteotomies, as well as anterior soft tissue releases.

Methods

One patient with dropped head deformity underwent an anterior and posterior osteotomy with anterior soft tissue release.

Results

The patient recovered well, with postoperative radiographs demonstrating significant improvement in coronal and sagittal alignment. His C2–C7 sagittal vertical axis improved from 7.5 cm preoperatively to less than 4 cm postoperatively and his C2–C7 sagittal Cobb improved from 35° of kyphosis to 10° of lordosis.

Conclusion

In this report, we present our technique for a large focal correction of a partially flexible dropped head deformity through combined anterior and posterior osteotomies and anterior soft tissue releases. These more conservative osteotomies permitted gradual deformity correction and alleviated the need for pedicle subtraction osteotomy. We were able to restore horizontal gaze and improve sagittal malalignment. Although the technique we present here is one of many possible options for managing the deformity, we believe this combined approach is safe and effective and well tolerated by patients.

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Cancer epigenetics: Therapy-induced transcription is cryptically widespread

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Disease genetics: Repeat expansion disorders — going through a phase

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Synthetic lethality and cancer

The authors review the concept of synthetic lethality — when the perturbation of one of two genes alone is viable, but the perturbation of both genes simultaneously results in the loss of viability — from model organisms to human cancers, and discuss how genetic interactions can be exploited for the identification of new drug targets in cancer.

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Gluten and Aluminum Content in Synthroid ® (Levothyroxine Sodium Tablets)

Abstract

Introduction

Inquiries from healthcare providers and patients about the gluten and aluminum content of Synthroid^® (levothyroxine sodium tablets) have increased. The objective of this study was to measure and evaluate the gluten content of the raw materials used in the manufacturing of Synthroid. Additionally, this study determined the aluminum content in different strengths of Synthroid tablets by estimating the amount of aluminum in the raw materials used in the manufacturing of Synthroid.

Methods

Gluten levels of three lots of the active pharmaceutical ingredient (API) and one lot of each excipient from different vendors were examined. The ingredients in all current Synthroid formulations (strengths) were evaluated for their quantity of aluminum.

Results

Gluten concentrations were below the lowest limit of detection (<3.0 ppm) for all tested lots of the API and excipients of Synthroid tablets. Aluminum content varied across tablet strengths (range 19–137 µg/tablet). Gluten levels of the API and excipients were found to be below the lowest level of detection and are considered gluten-free based on the US Food and Drug Administration (FDA) definition for food products. Across the various tablet strengths of Synthroid, the maximum aluminum levels were well below the FDA-determined minimal risk level for chronic oral aluminum exposure (1 mg/kg/day).

Conclusion

These data demonstrate that Synthroid tablets are not a source for dietary gluten and are a minimal source of aluminum.

Funding

AbbVie Inc.

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Urgent need to strengthen and expand screening and other cancer control programs in the CARICOM Caribbean

Abstract

Purpose

With high mortality in breast, cervical, prostate, and colorectal cancers in Caribbean Community (CARICOM) countries, we examined cancer control initiatives including screening as well as the implementation of relevant international and regional mandates.

Methods

Secondary data were used to examine cancer control initiatives, which included the presence of national policies, programs, and screening services as well as the implementation of international and regional mandates. To identify the data, an on-line search was conducted using Google/Google Scholar.

Results

Data were available for 14 of the 15 full members of CARICOM. Although only six countries had distinct cancer control policies, strategies or action plans, all 14 had key elements of cancer control programs. Screening services were available in the 14 countries for cervical, in 12 countries for breast and in 11 for colorectal cancer. However, only four countries had screening policies. In addition, screening guidelines were available for cervical cancer in nine countries, in one country for breast and in none for colorectal cancer. Selected tobacco control policies were present in the 14 countries and immunization policies for human papillomavirus (HPV) in 13. Treatment services included chemotherapy in 10 countries and radiotherapy in six. Nine countries had palliative care services for patients with advanced disease. The countries were at different stages of implementation/compliance with international and regional mandates and frameworks.

Conclusions

There is an urgent need to develop and implement comprehensive and customized cancer control policies addressing screening programs, treatment and palliative care.

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EMCrit 202 – Blood Bank Essentials with Joe Chaffin

blood bank stuff: The basics of crit care transfusion medicine

EMCrit by Scott Weingart.

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New nano-hydroxyapatite in bone defect regeneration: a histological study in rats

Publication date: Available online 24 June 2017
Source:Annals of Anatomy - Anatomischer Anzeiger
Author(s): Paweł Kubasiewicz-Ross, Jakub Hadzik, Julia Seeliger, Karol Kozak, Kamil Jurczyszyn, Hanna Gerber, Marzena Dominiak, Christiane Kunert-Keil
Many types of bone substitute materials are available on the market. Researchers are refining new bone substitutes to make them comparable to autologous grafting materials in treatment of bone defects. The purpose of the study was to evaluate the osseoconductive potential and bone defect regeneration in rat calvaria bone defects treated with new synthetic nano-hydroxyapatite. The study was performed on 30 rats divided into 5 equal groups. New preproduction of experimental nano-hydroxyapatite material by NanoSynHap (Poznań, Poland) was tested and compared with commercially available materials. Five mm critical size defects were created and filled with the following bone grafting materials: 1) Geistlich Bio-Oss^®; 2) nano-hydroxyapatite + β-TCP; 3) nano-hydroxyapatite; 4) nano-hydroxyapatite+collagen membrane. The last group served as controls without any augmentation. Bone samples from calvaria were harvested for histological and micro-ct evaluation after 8 weeks. New bone formation was observed in all groups. Histomorphometric analysis revealed an amount of regenerated bone between 34.2 and 44.4% in treated bone defects, whereas only 13.0% regenerated bone was found in controls. Interestingly, in group 3, no significant particles of the nano-HA material were found. In contrast, residual bone substitute material could be detected in all other test groups. Micro-CT study confirmed the results of the histological examinations. The new nano-hydroxyapatite provides comparable results to other grafts in the field of bone regeneration.



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Osteonecrosis of the jaws: a review and update in etiology and treatment

Publication date: Available online 24 June 2017
Source:Brazilian Journal of Otorhinolaryngology
Author(s): Guilherme H. Ribeiro, Emanuely S. Chrun, Kamile L. Dutra, Filipe I. Daniel, Liliane J. Grando
IntroductionOsteonecrosis of the jaws (ONJ) can result either from radiation, used in radiotherapy (RT) for treatment of malignant tumors, or medications used for bone remodeling and anti-angiogenesis such as bisphosphonates (BPs). These conditions can be associated with triggering factors such as infection, trauma and decreased vascularity. The management of patients with ONJ requires caution since there is no specific treatment that acts isolated and decidedly. However, different treatment modalities can be employed in an associated manner to control and stabilize lesions.ObjectiveTo review the current knowledge on etiology and management of ONJ, both radio-induced and medication-related, aiming to improve knowledge of professionals seeking to improve the quality of life of their patients.MethodsLiterature review in PubMed as well as manual search for relevant publications in reference list of selected articles. Articles in English ranging from 1983 to 2017, which assessed ONJ as main objective, were selected and analyzed.ResultsInfections, traumas and decreased vascularity have a triggering role for ONJ. Prophylactic and/or stabilizing measures can be employed in association with therapeutic modalities to properly manage ONJ patients.ConclusionSelecting an appropriate therapy for ONJ management based on current literature is a rational decision that can help lead to a proper treatment plan.



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Primary epithelial salivary gland tumours in children and adolescents

Publication date: Available online 24 June 2017
Source:International Journal of Oral and Maxillofacial Surgery
Author(s): M. Gontarz, G. Wyszyńska-Pawelec, J. Zapała
Primary epithelial tumours of the salivary glands are very rare in paediatric patients. The aim of this study was to evaluate the clinical course, treatment, and outcomes of these uncommon neoplasms based on the authors’ experience and the recent literature. The medical charts of 12 female patients and seven male patients with primary epithelial salivary gland tumours were reviewed. All were under 19 years of age and underwent surgical treatment between 1994 and 2016. The results of this group of paediatric patients were compared with those of 621 adult patients. The two most common tumours in the paediatric patients were pleomorphic adenoma and mucoepidermoid carcinoma (89.4%; P=0.004). The incidence of facial nerve palsy following surgery of the parotid tumours was similar in the two groups (P=1.000). The most common primary cancer in the paediatric group was mucoepidermoid carcinoma (77.8%), while in the adult group, adenoid cystic carcinoma was most common (P<0.001). The paediatric group had only low-grade cancers in early stages (P<0.001), with an overall 5-year survival rate of 100%. These results show that the incidence of malignant salivary gland tumours is higher in paediatric patients than in adult patients. This should be taken into account during diagnosis and therapy.



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Immediate full-arch rehabilitation of the severely atrophic maxilla supported by zygomatic implants: a prospective clinical study with minimum follow-up of 6 years

Publication date: Available online 24 June 2017
Source:International Journal of Oral and Maxillofacial Surgery
Author(s): E.L. Agliardi, D. Romeo, S. Panigatti, M. de Araújo Nobre, P. Maló
The aim of this study was to evaluate the outcomes of immediate full-arch prostheses supported by zygomatic implants alone or in combination with standard fixtures after a minimum of 6 years of loading. From October 2008 to April 2010, 15 patients with severely atrophic maxillae were treated using four zygomatic implants or two zygomatic implants in conjunction with two conventional fixtures. All subjects received a fixed screw-retained prosthesis within 3hours of surgery, while the final restoration was delivered after 6 months. Follow-up examinations were scheduled to evaluate zygomatic implant survival, conventional dental implant success, prosthetic success, plaque and bleeding scores, marginal bone loss for conventional dental implants, and patient satisfaction. Forty-two zygomatic fixtures and 18 standard implants were placed. Patients were followed up for a minimum of 79 months (range 79–97 months, average 90.61 months). No implant was lost, leading to implant and prosthetic survival rates of 100%. Bone loss for conventional implants averaged 1.39±0.10mm after 6 years of function, leading to a 100% implant success rate. High levels of patient satisfaction were recorded. These medium-term results indicate that immediate full-arch rehabilitation supported by zygomatic implants could be considered a viable treatment modality for the severely atrophic maxilla.



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Different hypersensitivities against homologous proteins of MGL_1304 in patients with atopic dermatitis

Publication date: Available online 24 June 2017
Source:Allergology International
Author(s): Takuma Kohsaka, Takaaki Hiragun, Kaori Ishii, Makiko Hiragun, Akiko Kamegashira, Michihiro Hide
BackgroundAtopic dermatitis (AD) is exacerbated by sweating, and the skin of most patients with AD are resided by Malassezia (M.) fungi. Recently, MGL_1304 produced by Malasseziaglobosa was identified as the major histamine releasing antigen in human sweat.MethodsThe full length cDNA of the counterpart of MGL_1304 in Malasseziarestricta (Mala r 8), was cloned by degenerate PCR and rapid identification of cDNA ends (RACE). Recombinant MGL_1304, and its counterparts, Mala s 8 (produced by Malasseziasympodialis) and Mala r 8 were prepared, and compared in their allergenicities by dot blot analysis and histamine release tests with sera and basophils of patients with AD.ResultsThe identities between MGL_1304 and Mala s 8, MGL_1304 and Mala r 8, and Mala s 8 and Mala r 8 were 68%, 78%, and 76%, respectively, in protein sequences. Dot blot analysis revealed that the level of IgE binding to Mala s 8 was higher than that of MGL_1304. However, histamine release tests revealed that MGL_1304 and Mala r 8 possessed higher activity than Mala s 8. In addition, the crude lysate of M. globosa showed higher histamine release ability than that of M. sympodialis.ConclusionsPatients with AD showed hypersensitivities against MGL_1304 and its homologs. However, the allergenicities of the homologs are variable and the histamine release activities may be different from the solid-phase binding activities for IgE. Sweat allergy should be carefully evaluated with biological activities of MGL_1304 and its homologs of other Malassezia fungi residing on the skin.



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Generation and characterization of a human oral squamous carcinoma cell line SCC-9 with CRISPR/Cas9-mediated deletion of the p75 neurotrophin receptor

Publication date: October 2017
Source:Archives of Oral Biology, Volume 82
Author(s): Ping Huang, Dongdong Tong, Jing Sun, Qing Li, Fenghe Zhang
ObjectiveTo investigate the importance of the p75 neurotrophin receptor (p75^NTR) in human tongue squamous carcinoma cells, we exploited the CRISPR/Cas9 technology to establish a p75^NTR-knockout SCC-9 cell line and to explore the effect on biological functions.Materials and methodsThe clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated endonuclease (Cas9) system was used to generate genomic deletion mutants of p75^NTR in the tongue squamous carcinoma cell lines SCC-9. Single-guide RNA (sgRNA) sequences were designed to target the p75^NTR genomic sequence and were cloned into plasmid pGK1.1. The linearized vector was electroporated into SCC-9 cells and p75^NTR deletion was confirmed using Cruiser™ enzyme digestion and PCR amplification. SCC-9 clones with successful deletion of p75^NTR were identified and verified by sequencing and selected for functional testing in cell proliferation, invasion, migration, and colony-forming assays.ResultsCompared with control cells, p75^NTR-knockout SCC-9 cells showed significantly diminished abilities to proliferate, invade, migrate, and form colonies, indicating a reduction in pro-tumorigenic behavior.ConclusionThese data demonstrate, first, that the CRISPR/Cas9 system is a simplified method for generating p75^NTR knockouts with relatively high efficiency, and second, that deletion of p75^NTR suppresses several tumor-promoting properties of SCC-9 cells, suggesting that p75^NTR is a potential target for the development of novel therapies for tongue cancer.



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Fibulins and matrilins are novel structural components of the periodontium in the mouse

Publication date: October 2017
Source:Archives of Oral Biology, Volume 82
Author(s): Andrea Schubert, Boris Schminke, Nicolai Miosge
Periodontitis refers to inflammatory disease of the periodontal structures (the gingiva, dental cementum, periodontal ligament (PDL) and alveolar bone) that ultimately leads to their destruction. Whereas collagens are well-examined main components of the periodontium, little is known about the other structural proteins that make up this tissue. The aim of this study was to identify new extracellular matrix (ECM) components, including fibulins and matrilins, in the periodontium of mice.After sacrificing 14 mice (Sv/129 strain), jaws were prepared. Each tissue sample contained a molar and its surrounding alveolar bone. Immunohistochemistry was carried out on paraffin-embedded sections.Our results show that mice exhibit fibulin-3, -4 and -5 and matrilin-1, -2, -3 and -4 in PDL and in blood vessels of alveolar bone and PDL as well as in the pericellular matrix of osteocytes and cementocytes. In dental cementum, only fibulin-4 is expressed.For the first time, we show that fibulin-3, -4 and -5 and matrilin-1, -2, -3 and -4 are essential components of the periodontal tissues. Our findings indicate an association of these proteins with collagens and oxytalan fibers that might be of future interest in regenerative periodontitis therapy.



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In Silico Shear and Intramural Stresses are Linked to Aortic Valve Morphology in Dilated Ascending Aorta

Publication date: Available online 24 June 2017
Source:European Journal of Vascular and Endovascular Surgery
Author(s): S. Pasta, G. Gentile, G.M. Raffa, D. Bellavia, G. Chiarello, R. Liotta, A. Luca, C. Scardulla, M. Pilato
Objective/BackgroundThe development of ascending aortic dilatation in patients with bicuspid aortic valve (BAV) is highly variable, and this makes surgical decision strategies particularly challenging. The purpose of this study was to identify new predictors, other than the well established aortic size, that may help to stratify the risk of aortic dilatation in BAV patients.MethodsUsing fluid–structure interaction analysis, both haemodynamic and structural parameters exerted on the ascending aortic wall of patients with either BAV (n = 21) or tricuspid aortic valve (TAV; n = 13) with comparable age and aortic diameter (42.7 ± 5.3 mm for BAV and 45.4 ± 10.0 mm for TAV) were compared. BAV phenotypes were stratified according to the leaflet fusion pattern and aortic shape.ResultsSystolic wall shear stress (WSS) of BAV patients was higher than TAV patients at the sinotubular junction (6.8 ± 3.3 N/m² for BAV and 3.9 ± 1.3 N/m² for TAV; p = .006) and mid-ascending aorta (9.8 ± 3.3 N/m² for BAV and 7.1 ± 2.3 N/m² for TAV; p = .040). A statistically significant difference in BAV versus TAV was also observed for the intramural stress along the ascending aorta (e.g., 2.54 × 10⁵ ± 0.32 × 10⁵ N/m² for BAV and 2.04 × 10⁵ ± 0.34 × 10⁵ N/m² for TAV; p < .001) and pressure index (0.329 ± 0.107 for BAV and 0.223 ± 0.139 for TAV; p = .030). Differences in the BAV phenotypes (i.e., BAV type 1 vs. BAV type 2) and aortopathy (i.e., isolated tubular vs. aortic root dilatations) were associated with asymmetric WSS distributions in the right anterior aortic wall and right posterior aortic wall, respectively.ConclusionThese findings suggest that valve mediated haemodynamic and structural parameters may be used to identify which regions of aortic wall are at greater stress and enable the development of a personalised approach for the diagnosis and management of aortic dilatation beyond traditional guidelines.



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Age-related plantar centre of pressure trajectory changes during barefoot walking

Publication date: September 2017
Source:Gait & Posture, Volume 57
Author(s): Gisela Sole, Todd Pataky, Christopher C. Sole, Leigh Hale, Stephan Milosavljevic
Plantar centre of pressure (COP) variables during gait have been used to predict risk of injury, or consequences thereof. The aim of this study was to determine the effect of age on the COP trajectory during barefoot gait at a self-selected speed. 287 participants (aged 18–80year, 163 women) walked barefoot at self-selected speed across a Footscan^® force platform, completing five trials for each side. COP trajectories were extracted and trajectory-level canonical correlation analysis was used to test their correlation with age. Post hoc linear regressions were performed on the medio-lateral (COPx) and anterior-posterior (COPy) components. The test statistic trajectory exceeded the critical threshold for the left (p=0.001) and right foot (p=0.003). Post hoc analyses showed positive correlation between age and COPx in late stance, placed more laterally with increasing age, while no significant correlation was found for COPy. While no significant correlations were observed for the test statistic trajectory during heel strike and mid-stance, post hoc analysis indicated that the COPx component was placed more laterally at heel strike for the left foot with increasing age (p=0.016). The findings suggest that older individuals tend to push-off with less metatarso-phalangeal dorsiflexion. These results do not necessarily imply that ageing itself causes the observed correlation. Further evidence is needed to determine whether the laterally placed COP during roll-off may be a useful factor for determining risk for falling in the older population, or as a risk for future injuries or overuse disorders.



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Corrigendum.

Related Articles

Corrigendum.

Chem Senses. 2017 Jun 21;:

Authors:

PMID: 28645147 [PubMed - as supplied by publisher]

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Effects of Acute Altered Gravity During Parabolic Flight and/or Vestibular Loss on Cell Proliferation in the Rat Dentate Gyrus.

Related Articles

Effects of Acute Altered Gravity During Parabolic Flight and/or Vestibular Loss on Cell Proliferation in the Rat Dentate Gyrus.

Neurosci Lett. 2017 Jun 20;:

Authors: Zheng Y, Gliddon CM, Aitken P, Stiles L, Machado ML, Philoxene B, Denise P, Smith PF, Besnard S

Abstract
Both parabolic flight, i.e. a condition of altered gravity, and loss of vestibular function, have been suggested to affect spatial learning and memory, which is known to be influenced by neurogenesis in the hippocampus. In this study we investigated whether short alternated micro- and hyper-gravity stimulations during parabolic flight and/or loss of vestibular function, would alter cell proliferation in the hippocampal dentate gyrus of rats, by measuring the number of bromodeoxyuridine (BrdU)-incorporated cells. Rats were randomly allocated to the following experimental groups: (1) sham transtympanic saline injection only (n=5); (2) bilateral vestibular deafferentation (BVD) by sodium arsanilate transtympanic injection only (n=5); (3) sham treatment and parabolic flight (n=5); (4) BVD and parabolic flight (n=6). Forty-two days following transtympanic injection, the animals were subjected to parabolic flight in an awake restrained condition after habituation. A modified Airbus A300 aircraft was flown on a parabolic path, creating 20 secs of 1.8G during both climbing and descending and 22 secs of 0G at the apex of each parabola. The no flight animals were subjected to the same housing for the same duration. Immediately after the parabolic flight or control ground condition, animals were injected with BrdU (300mg/kg, i.p). Twenty-four hs after BrdU injection, rats were sacrificed. BrdU immunolabelling was performed and the number of BrdU(+ve) cells in the dentate gyrus of the hippocampus was quantified using a modified fractionator method. BVD caused a large and significant reduction in the number of BrdU-positive cells compared to sham animals (P≤0.0001); however, flight and all interactions were non-significant. These results indicate that BVD significantly decreased cell proliferation irrespective of the short exposure to altered/modified gravity.

PMID: 28645788 [PubMed - as supplied by publisher]

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The impact of argon/oxygen low-pressure plasma on shear bond strength between a veneering composite and different PEEK materials

Publication date: Available online 24 June 2017
Source:Dental Materials
Author(s): Andreas Dominik Schwitalla, Friederike Bötel, Tycho Zimmermann, Mona Sütel, Wolf-Dieter Müller
ObjectiveThe aim of the study was to evaluate the impact of low-pressure argon/oxygen plasma with and without previous sandblasting on the shear bond strength (SBS) between dental PEEK compounds and a veneering composite.MethodsOf one type of unfilled PEEK and two pigment powder filled PEEK compounds, forty rectangular plates each were prepared and polished up to 4000 grit. The samples were randomly assigned to four surface pre-treatment groups, each consisting of ten specimens (1. Untreated; 2. Plasma treatment; 3. Sandblasting; 4. Sandblasting+plasma treatment). Plasma treatment was performed for 35min using a low-pressure plasma system with a 1:1 mixture of the process gases argon and oxygen. Surface roughness and water contact angles were recorded. An adhesive (Visio.link, Bredent GmbH & Co KG, Senden, Germany) was applied onto the specimen surfaces and light cured. A mold was used to shape the veneering composite (Vita VM LC, Vita Zahnfabrik, Bad Säckingen, Germany) into a cylindrical form on the sample surface before light curing. SBS was measured after 24h incubation at 37°C in distilled water using a universal testing machine.ResultsThe samples pre-treated according to group 4 (sandblasting and plasma treatment) showed the highest SBS overall, whereas the unfilled PEEK showed the highest SBS (19.8±2.46MPa) compared to the other PEEK materials (15.86±4.39MPa and 9.06±3.1MPa).SignificanceSandblasting and surface activation with low-pressure argon/oxygen plasma in combination with an adhesive causes a favorable increase in shear bond strength, especially on unfilled PEEK material.



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Enhanced Skin Reaction with Palliative Thoracic Radiotherapy and Sorafenib

Publication date: Available online 24 June 2017
Source:Practical Radiation Oncology
Author(s): Diane C Ling, Danielle Bell, Michael Wollman, Seong-Kyun Cheong, Melvin Deutsch, John A Vargo




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Anatomical Regional Targeted (ART) BOTOX Injection Technique: A Novel Paradigm for Migraines and Chronic Headaches: Erratum

No abstract available

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