Source:Dental Materials, Volume 34, Issue 4
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Τετάρτη 14 Μαρτίου 2018
Editorial Board
Source:Dental Materials, Volume 34, Issue 4
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Evaluation of biofilm formation on novel copper-catalyzed azide-alkyne cycloaddition (CuAAC)-based resins for dental restoratives
Source:Dental Materials, Volume 34, Issue 4
Author(s): Sheryl Zajdowicz, Han Byul Song, Austin Baranek, Christopher N. Bowman
ObjectiveFor the past several decades, the resins used in dental restorations have been plagued with numerous problems, including their implication in biofilm formation and secondary caries. The need for alternative resins is critical, and evaluation of biofilm formation on these resins is essential. The aim of this study was to evaluate in vitro biofilm formation on the surface of novel copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC)-based resins and composites.MethodsCuAAC-based resins/composites made from varying azide monomers and different copper concentrations were compared with BisGMA-TEGDMA resins/composites that served as the control. Biofilms were formed using a mono-species model containing a luciferase-expressing strain of Streptococcus mutans. Luciferase activity was measured and the number of viable bacteria was enumerated on biofilms associated with each resin and composite.ResultsA significant reduction (p<0.05) in luciferase activity, and the number of viable bacteria recovered from biofilms on CuAAC-based resins and composites was observed in comparison to biofilms associated with the BisGMA-TEGDMA controls.SignificanceCuAAC-based resins do still allow for the formation of biofilms; however, the statistically significant reduction of growth that was associated with the CuAAC resin may enhance the longevity of restorations that incorporate CuAAC-based materials.
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Polymerization efficiency affects interfacial fracture toughness of adhesives
Source:Dental Materials, Volume 34, Issue 4
Author(s): Pong Pongprueksa, Jan De Munck, Masanao Inokoshi, Bart Van Meerbeek
ObjectiveTo evaluate the effect of the kind and concentration of photo-initiator on the degree of conversion (DC) of adhesives on dentin/glass substrates and their mini-interfacial fracture toughness (mini-iFT) to dentin.MethodsWe tested the adhesive Clearfil S3 Bond Plus and 4 derived experimental 'LUB' ('Leuven Univesity Bond') adhesives (all from Kuraray Noritake), namely 'LUB-CQ/amine_high', 'LUB-CQ/amine_low', 'LUB-TPO_high', and 'LUB-TPO_low', respectively containing 2.0wt% camphorquinone (CQ) and 2.0wt% EDMAB (amine), 0.35wt% CQ and 0.35wt% amine, 2.0wt% TPO, and 0.35wt% TPO. For DC, each adhesive was applied onto glass or dentin prior to being cured (Bluephase 20i; Ivoclar Vivadent: "high mode") for 10s. DC was measured at 5min, 10min, 1h, 24h and 1 week using micro-Raman spectroscopy (SENTERRA; BrukerOptik). For mini-iFT, each adhesive was bonded to 320-grit SiC-paper ground dentin and covered with composite (Z100; 3M ESPE). The restored teeth were cut in sticks (1.5×2.0×16mm), after which a single-gradient notch was prepared at the adhesive-dentin interface using a 150-μm diamond blade. The micro-specimens were loaded until failure in a 4-point bending test and the mini-iFT in term of KQvM was calculated.ResultsDC was higher on dentin than on glass. All adhesives were adequately polymerized at 1 week, except for LUB-TPO_low. DC at 5min was significantly higher for LUB-TPO_high than for both CQ/amine-based adhesives. The highest and most reliable mini-iFT was measured for LUB-CQ/amine_high, despite its 5-min DC was relatively low. No correlation between DC and mini-iFT was found.SignificanceCuring of TPO-based adhesives is faster, but the dark cure of the CQ/amine-containing adhesives is more efficient. The differences in curing profiles do affect the mechanical properties of the resultant interfaces at dentin.
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Shining a light on high volume photocurable materials
Source:Dental Materials
Author(s): William M. Palin, Julian G. Leprince, Mohammed A. Hadis
Spatial and temporal control is a key advantage for placement and rapid setting of light-activated resin composites. Conventionally, placement of multiple thin layers (<2mm) reduces the effect of light attenuation through highly filled and pigmented materials to increase polymerisation at the base of the restoration. However, and although light curing greater than 2mm thick layers is not an entirely new phenomenon, the desire amongst dental practitioners for even more rapid processing in deep cavities has led to the growing acceptance of so-called "bulk fill" (4–6mm thick) resin composites that are irradiated for 10–20s in daily clinical practice. The change in light transmission and attenuation during photopolymerisation are complex and related to path length, absorption properties of the photoinitiator and pigment, optical properties of the resin and filler and filler morphology. Understanding how light is transmitted through depth is therefore critical for ensuring optimal material properties at the base of thick increments. This article will briefly highlight the advent of current commercial materials that rationalise bulk filling techniques in dentistry, the relationship between light transmission and polymerisation and how optimal curing depths might be achieved.
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Bacterial Call to Arms for Warfare at the Infection Site
Publication date: 14 March 2018
Source:Cell Host & Microbe, Volume 23, Issue 3
Author(s): Vitor Cabral, Karina B. Xavier
Bacterial sensing is important for perceiving environmental cues and activating responses. In this issue of Cell Host & Microbe, Hertzog et al. (2018) show that group A Streptococcus can couple the ability to respond to host cues with autoinduction of a quorum sensing system, leading to killing of bacterial competitors.
Teaser
Bacterial sensing is important for perceiving environmental cues and activating responses. In this issue of Cell Host & Microbe, Hertzog et al. (2018) show that group A Streptococcus can couple the ability to respond to host cues with autoinduction of a quorum sensing system, leading to killing of bacterial competitors.http://ift.tt/2FK1BDL
Lipid Catabolism Fuels Drosophila Gut Immunity
Publication date: 14 March 2018
Source:Cell Host & Microbe, Volume 23, Issue 3
Author(s): Ambra Masuzzo, Julien Royet
Immune responses and metabolic regulation are tightly coupled in animals, but the underlying mechanistic connections are not fully understood. In this issue of Cell Host & Microbe, Lee et al. (2018) reveal how sustained ROS production in the gut depends on an upstream metabolic switch.
Teaser
Immune responses and metabolic regulation are tightly coupled in animals, but the underlying mechanistic connections are not fully understood. In this issue of Cell Host & Microbe, Lee et al. reveal how sustained ROS production in the gut depends on an upstream metabolic switch.http://ift.tt/2pdrgyB
Templating Antiviral RNAi in Insects
Publication date: 14 March 2018
Source:Cell Host & Microbe, Volume 23, Issue 3
Author(s): Yanhong Han, Qingfa Wu, Shou-Wei Ding
Virus-specific small interfering RNAs (siRNAs) are a central component of antiviral responses in insects. In this issue of Cell Host & Microbe, Poirier et al. (2018) demonstrate that virus-infected flies and mosquitoes produce virus-derived extrachromosomal circular DNAs that serve as a template for the biogenesis of antiviral siRNAs.
Teaser
Virus-specific small interfering RNAs (siRNAs) are a central component of antiviral responses in insects. In this issue of Cell Host & Microbe, Poirier et al. (2018) demonstrate that virus-infected flies and mosquitoes produce virus-derived extrachromosomal circular DNAs that serve as a template for the biogenesis of antiviral siRNAs.http://ift.tt/2FJ5TeN
A Sleeping Area of Malaria Research Awakes
Publication date: 14 March 2018
Source:Cell Host & Microbe, Volume 23, Issue 3
Author(s): Elizabeth A. Winzeler
Phenotypic screening methods have had a profound impact on antimalarial drug development, but assays that predict which compounds might provide a radical cure have remained elusive. In this issue of Cell Host & Microbe, Gural et al. (2018) report hypnozoite culturing and systems to study these elusive, yet deadly, parasites.
Teaser
Phenotypic screening methods have had a profound impact on antimalarial drug development, but assays that predict which compounds might provide a radical cure have remained elusive. In this issue of Cell Host & Microbe, Gural et al. (2018) report hypnozoite culturing and systems to study these elusive, yet deadly, parasites.http://ift.tt/2FBqcii
How Good Roommates Can Protect against Microbial Sepsis
Publication date: 14 March 2018
Source:Cell Host & Microbe, Volume 23, Issue 3
Author(s): Rudi Beyaert, Claude Libert
In this issue of Cell Host & Microbe, Wilmore et al. (2018) co-housed isogenic mouse populations, uncovering commensal bacteria-induced serum IgA and IgA-producing bone marrow plasma cells as critical components of resistance against sepsis. They further identified gut microbial taxa that may account for the induction of this protective system.
Teaser
In this issue of Cell Host & Microbe, Wilmore et al. (2018) co-housed isogenic mouse populations, uncovering commensal bacteria-induced serum IgA and IgA-producing bone marrow plasma cells as critical components of resistance against sepsis. They further identified gut microbial taxa that may account for the induction of this protective system.http://ift.tt/2HCDqrz
The β2 Integrin Mac-1 Induces Protective LC3-Associated Phagocytosis of Listeria monocytogenes
Publication date: 14 March 2018
Source:Cell Host & Microbe, Volume 23, Issue 3
Author(s): Alexander Gluschko, Marc Herb, Katja Wiegmann, Oleg Krut, Wolfram F. Neiss, Olaf Utermöhlen, Martin Krönke, Michael Schramm
The intracellular pathogen Listeria monocytogenes (L.m.) is targeted by the autophagic machinery, but the molecular mechanisms involved and consequences for anti-listerial immunity remain enigmatic. Here, we demonstrate that L.m. infection of macrophages in vivo exclusively evokes LC3-associated phagocytosis (LAP), but not canonical autophagy, and that targeting of L.m. by LAP is required for anti-listerial immunity. The pathway leading to LAP induction in response to L.m. infection emanates from the β2 integrin Mac-1 (CR3, integrin αMβ2), a receptor recognizing diverse microbial ligands. Interaction of L.m. with Mac-1 induces acid sphingomyelinase-mediated changes in membrane lipid composition that facilitate assembly and activation of the phagocyte NAPDH oxidase Nox2. Nox2-derived reactive oxygen species then trigger LC3 recruitment to L.m.-containing phagosomes by LAP. By promoting fusion of L.m.-containing phagosomes with lysosomes, LAP increases exposure of L.m. to bactericidal acid hydrolases, thereby enhancing anti-listerial activity of macrophages and immunity of mice.
Graphical abstract
Teaser
Listeria monocytogenes are targeted by the autophagic machinery via unclear molecular mechanisms. Gluschko and Herb et al. demonstrate that LC3-associated phagocytosis, but not canonical autophagy, is required for elimination of L. monocytogenes by macrophages and activated by the β2 integrin Mac-1 (CR3, integrin αMβ2).http://ift.tt/2HAUX3r
Reshaping of the Dendritic Cell Chromatin Landscape and Interferon Pathways during HIV Infection
Publication date: 14 March 2018
Source:Cell Host & Microbe, Volume 23, Issue 3
Author(s): Jarrod S. Johnson, Sasha Y. Lucas, Lynn M. Amon, Stephanie Skelton, Rodolfo Nazitto, Sara Carbonetti, D. Noah Sather, Dan R. Littman, Alan Aderem
Myeloid dendritic cells (DCs) have the innate capacity to sense pathogens and orchestrate immune responses. However, DCs do not mount efficient immune responses to HIV-1, primarily due to restriction of virus reverse transcription, which prevents accumulation of viral cDNA and limits its detection through the cGAS-STING pathway. By allowing reverse transcription to proceed, we find that DCs detect HIV-1 in distinct phases, before and after virus integration. Blocking integration suppresses, but does not abolish, activation of the transcription factor IRF3, downstream interferon (IFN) responses, and DC maturation. Consistent with two stages of detection, HIV-1 "primes" chromatin accessibility of innate immune genes before and after integration. Once primed, robust IFN responses can be unmasked by agonists of the innate adaptor protein, MyD88, through a process that requires cGAS, STING, IRF3, and nuclear factor κB. Thus, HIV-1 replication increases material available for sensing, and discrete inflammatory inputs tune cGAS signaling to drive DC maturation.
Graphical abstract
Teaser
Parameters regulating the innate immune response to HIV-1 remain unclear. Johnson et al. elucidate how dendritic cells sense HIV-1 in two stages. They demonstrate that cGAS/STING signaling can be tuned through unrelated pathways to unmask interferon responses before and after HIV-1 integration.http://ift.tt/2FByzdw
Single Particle Imaging of Polarized Hepatoma Organoids upon Hepatitis C Virus Infection Reveals an Ordered and Sequential Entry Process
Publication date: 14 March 2018
Source:Cell Host & Microbe, Volume 23, Issue 3
Author(s): Yasmine Baktash, Anisha Madhav, Kelly E. Coller, Glenn Randall
Hepatitis C virus (HCV) enters hepatocytes via various entry factors, including scavenger receptor BI (SR-B1), cluster of differentiation 81 (CD81), epidermal growth factor receptor (EGFR), claudin-1 (CLDN1), and occludin (OCLN). As CLDN1 and OCLN are not readily accessible due to their tight junctional localization, HCV likely accesses them by either disrupting cellular polarity or migrating to the tight junction. In this study, we image HCV entry into a three-dimensional polarized hepatoma system and reveal that the virus sequentially engages these entry factors through actin-dependent mechanisms. HCV initially localizes with the early entry factors SR-B1, CD81, and EGFR at the basolateral membrane and then accumulates at the tight junction in an actin-dependent manner. HCV associates with CLDN1 and then OCLN at the tight junction and is internalized via clathrin-mediated endocytosis by an active process requiring EGFR. Thus, HCV uses a dynamic and multi-step process to engage and enter host cells.
Graphical abstract
Teaser
HCV entry is complex and involves multiple host factors. By imaging the infection of polarized hepatoma organoids with fluorescent HCV virions, Baktash et al. define the sequence of events during entry. They determine that HCV virions traffic with early receptors to tight junctions and then internalize in an EGFR-dependent manner.http://ift.tt/2HzApYP
Bacteroides fragilis Toxin Coordinates a Pro-carcinogenic Inflammatory Cascade via Targeting of Colonic Epithelial Cells
Publication date: 14 March 2018
Source:Cell Host & Microbe, Volume 23, Issue 3
Author(s): Liam Chung, Erik Thiele Orberg, Abby L. Geis, June L. Chan, Kai Fu, Christina E. DeStefano Shields, Christine M. Dejea, Payam Fathi, Jie Chen, Benjamin B. Finard, Ada J. Tam, Florencia McAllister, Hongni Fan, Xinqun Wu, Sudipto Ganguly, Andriana Lebid, Paul Metz, Sara W. Van Meerbeke, David L. Huso, Elizabeth C. Wick, Drew M. Pardoll, Fengyi Wan, Shaoguang Wu, Cynthia L. Sears, Franck Housseau
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Soil uranium concentration at Ranger Uranium Mine Land Application Areas drives changes in the bacterial community
Source:Journal of Environmental Radioactivity, Volume 189
Author(s): Saqib Mumtaz, Claire Streten, David L. Parry, Keith A. McGuinness, Ping Lu, Karen S. Gibb
Soil microorganisms may respond to metal stress by a shift in the microbial community from metal sensitive to metal resistant microorganisms. We assessed the bacterial community from low (2–20 mg kg−1), medium (200–400 mg kg−1), high (500–900 mg kg−1) and very high (>900 mg kg−1) uranium soils at Ranger Uranium Mine in northern Australia through pyrosequencing. Proteobacteria (28.85%) was the most abundant phylum at these sites, followed by Actinobacteria (9.31%), Acidobacteria (7.33%), Verrucomicrobia (2.11%), Firmicutes (2.02%), Chloroflexi (1.11%), Cyanobacteria (0.93%), Planctomycetes (0.82%), Bacteroidetes (0.46%) and Candidate_division_WS3 (Latescibacteria) (0.21%). However, 46.79% of bacteria were unclassified. Bacteria at low U soils differed from soils with elevated uranium. Bacterial OTUs closely related to Kitasatospora spp., Sphingobacteria spp. and Rhodobium spp. were only present at higher uranium concentrations and the bacterial community also changed with seasonal and temporal changes in soil uranium and physicochemical variables. This study using next generation sequencing in association with environmental variables at a uranium mine has laid a foundation for further studies of soil-microbe-metal interactions which may be useful for developing sustainable management and rehabilitation strategies. Furthermore, bacterial species associated with higher uranium may serve as useful indicators of uranium contamination in the wet-dry tropics.
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Can Vagus Nerve Stimulation improve Social Cognition in Autism?
Publication date: Available online 15 March 2018
Source:Cortex
Author(s): Ashwin Kumaria, Murugan Sitaraman
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Color Doppler Twinkling Artifact in Diagnosis of Tuberculous Pleuritis: A Comparison with Gray-Scale Ultrasonography and Computed Tomography
Source:Ultrasound in Medicine & Biology
Author(s): Jiakai Tian, Liang Xu
The aim of this study was to determine whether twinkling artifact (TA) detected on color Doppler ultrasonography can effectively determine the presence of pleural calcification compared with computed tomography (CT) and differentiate tuberculous pleuritis (TP) and cancerous pleuritis (CP). One hundred six cases of TP and 26 cases of CP were scanned using gray-scale ultrasonography (GSU) and TA to determine the presence of pleural calcification. With CT as the reference standard, 63.3% and 79.6% of patients with pleural calcification were identified with GSU and TA, respectively. The detection rate of TA was higher than that of GSU (p = 0.039). For the whole study population, 37.1% were identified as having pleural calcification with CT, significantly higher than the proportion detected with GSU (25.8%, p = 0.001), but not different from that detected with TA (41.7%, p = 0.327). The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of TA were 79.6%, 80.7%, 80.3%, 70.9% and 87.0%, respectively. The detection rate of TA was significantly higher than that of GSU (p < 0.001). When GSU was combined with TA (GSUTA), the positive rate in the TP group was significantly higher than that in the CP group (χ2 < 0.001). In conclusion, TA is comparable to CT and more sensitive than GSU in the detection of pleural calcification. Evaluation for GSUTA on pleura may help to differentiate TP from CP.
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Pre-Treatment with Either L-Carnitine or Piracetam Increases Ultrasound-Mediated Gene Transfection by Reducing Sonoporation-Associated Apoptosis
Source:Ultrasound in Medicine & Biology
Author(s): Wei-Hao Liao, Chueh-Hung Wu, Wen-Shiang Chen
Sonoporation, the use of ultrasound to alter the permeability of cell membranes, is a non-viral technique used to facilitate gene delivery, possibly by opening transient pores in the cell membrane. However, sonoporation may have negative bio-effects on cells, such as causing apoptosis, which limits its efficacy in gene delivery. In this study, we investigated whether pre-treatment with either L-carnitine or piracetam could protect cells from undergoing apoptosis after sonoporation and the possible mechanisms. We found that either L-carnitine or piracetam can promote gene transfection without reducing cell viability, possibly by reducing cavitation-induced reactive oxygen species generation, reversing alterations of mitochondrial membrane potential, preventing caspase-3/7 activity and facilitating mitochondrial ATP production. In conclusion, pre-treatment with either L-carnitine or piracetam could protect cells from sonoporation-associated apoptosis by preserving mitochondrial function.
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Electroretinogram evaluation for the treatment of proliferative diabetic retinopathy by short-pulse pattern scanning laser panretinal photocoagulation
Abstract
Panretinal photocoagulation (PRP) is a standard method for proliferative diabetic retinopathy (PDR) treatment. However, conventional PRP usually significantly damages the retinal structure and vision. Retinal pattern scanning laser (PASCAL) photocoagulation has emerged as a new technique with fewer complications for the treatment of retinal disorders. This study compares the therapeutic effects of short-pulse PASCAL to conventional single-spot PRP for PDR. Fifty-two PDR patients (104 eyes) were randomly assigned into a short-pulse PASCAL-PRP treatment (SP) group and a conventional PRP treatment (TP) group. The best corrected visual acuity (BCVA) and full-field flash electroretinogram (ERG) data were evaluated before and after the two treatments. The BCVA data between before and after the PRP treatments did not show any significant difference. After the PRP treatment, the b-wave amplitude (b-A) in the dark-adapted 3.0 ERG (p = 0.0005) and the amplitude in the light-adapted 3.0 flicker ERG (p = 0.009) were significantly higher in the SP group compared with that of the TP group. In addition, after the PRP treatment, the a-wave implicit time (a-T) of light-adapted 3.0 ERG prolonged significantly in the TP group compared to the SP group. Compared with the parameters before the treatments, the a-A and b-A under dark-adapted 3.0 ERG and the b-A under the light-adapted 3.0 ERG in both TP and SP groups after the treatments decreased significantly (p < 0.05). Short-pulse PASCAL-PRP significantly attenuated partial vision damage compared to conventional PRP, although it still caused limited retinal injury and mild reduction in retinal function. These findings suggest that short-pulse PASCAL-PRP is a promising technique for PDR treatment.
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Immune response elicited by two rBCG strains devoid of genes involved in c-di-GMP metabolism affect protection versus challenge with M. tuberculosis strains of different virulence
Source:Vaccine
Author(s): Cristian Alfredo Segura-Cerda, Michel de Jesús Aceves-Sánchez, Brenda Marquina-Castillo, Dulce Mata-Espinoza, Jorge Barrios-Payán, Perla Jazmín Vega-Domínguez, César Pedroza-Roldán, Jorge Bravo-Madrigal, Alba Adriana Vallejo-Cardona, Rogelio Hernández-Pando, Mario Alberto Flores-Valdez
Pellicles, a type of biofilm, have gathered a renewed interest in the field of tuberculosis as a structure that mimics some characteristics occurring during M. tuberculosis infection, such as antibiotic recalcitrance and chronicity of infection, and as a source of antigens for humoral response in infected guinea pigs. In other bacteria, it has been well documented that the second messenger c-di-GMP modulates the transition from planktonic cells to biofilm formation. In this work, we used the live vaccine Mycobacterium bovis BCG to determine whether deletion of genes involved in c-di-GMP metabolism would affect interaction with macrophages, capacity to induce immune response in a murine cell line and mice, and how the protein profile was modified when grown as surface pellicles. We found that deletion of the BCG1419c (Delta c-di-GMP phosphodiesterase, ΔPDE) gene, or deletion of the BCG1416c (Delta c-di-GMP diguanylate cyclase, ΔDGC) gene, altered production of TNF-α, IL-6, and IL-1β, in murine macrophages, and resulted in attenuation in intra-macrophage replication. Moreover, in addition to the improved immunogenicity of the BCGΔBCG1419c mutant already reported, deletion of the BCG1416c gene leads to increased T CD4+ and T CD8+ activation. This correlated with protection versus lethality in mice infected with the highly virulent M. tuberculosis 5186 afforded by vaccination with all the tested BCG strains, and controlled the growth of the mildly virulent M. tuberculosis H37Rv in lungs by vaccination with BCGΔBCG1419c during chronic late infection from 4 to 6 months after challenge. Furthermore, when grown as surface pellicles, a condition used to manufacture BCG vaccine, in comparison to BCG wild type, both rBCGs changed expression of antigenic proteins such as DnaK, HbhA, PstS2, 35KDa antigen, GroEL2, as well as AcpM, a protein involved in synthesis of mycolic acids, molecules relevant to modulate inflammatory responses.
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Impact of dynamical and microphysical schemes on black carbon prediction in a regional climate model over India
Abstract
Aerosol concentrations and their properties strongly depend on dynamics of atmosphere. Effects of physical and dynamical parameterizations on meteorology and black carbon (BC) mass in Weather Research and Forecasting model coupled with Chemistry (WRF-CHEM) are investigated over India. Simulations are performed in ten experiments considering two boundary layer, three cumulus parameterization, and five microphysics schemes during winter and monsoon of 2008. Morrison double-moment physical parameterization, Yonsei University boundary layer parameterization with Kain-Fritsch and Grell-Freitas cumulus parameterization schemes are found suitable to simulate meteorology and BC mass over India. BC mass is found to be underestimated in almost all experiments during winter; while, BC mass is overestimated in monsoon over Ahmedabad, Delhi, and Kanpur, which suggests inefficient wet scavenging of BC in monsoon, while lower emission rate may cause differences in winter. The results will be useful in understanding parameterizations and their impact on aerosols.
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How to choose among the multiple options to enhance the penetration of topically applied methyl aminolevulinate prior to photodynamic therapy
Source:Photodiagnosis and Photodynamic Therapy, Volume 22
Author(s): Valerio De Vita
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Effectiveness of adjunctive antimicrobial photodynamic therapy in reducing peri-implant inflammatory response in individuals vaping electronic cigarettes: A randomized controlled clinical trial
Publication date: Available online 15 March 2018
Source:Photodiagnosis and Photodynamic Therapy
Author(s): Mohammed Q. Al Rifaiy, Osama A. Qutub, Mohammed N. Alasqah, Zeyad H. Al-Sowygh, Sameer A. Mokeem, Ali Alrahlah
BackgroundThere are no studies that have assessed the effectiveness of antimicrobial photodynamic therapy (aPDT) in reducing peri-implant inflammatory response in individuals vaping electronic cigarettes (e-cigs). This study explored the effectiveness of aPDT as an adjunct to mechanical debridement (MD) in the treatment of peri-implant mucositis (p-iM) in individuals vaping e-cigs.MethodsVaping individuals with p-iM were divided into 2 groups: (a) Group-I: receiving MD with aPDT (test group); and (b) Group-II: MD only (control group). Peri-implant inflammatory parameters including plaque index (PI), bleeding on probing (BoP), and pocket depth (PD) were assessed at baseline and 12-weeks follow-up. Inter- and intra-group comparisons were made using Mann-Whitney U test and Wilcoxon signed ranks test. P-value < 0.05 was considered significant.ResultsThirty-eight male patients (20 in Group-I and 18 in Group-II) were included. The mean age of vaping individuals in groups I and II were 33.6 ± 2.8 and 35.4 ± 2.1 years, respectively. Mean daily frequency of vaping e-cigs in groups I and II was 7.3 ± 0.9 and 5.9 ± 1.0 whereas mean duration of vaping e-cigs was 4.8 ± 1.5 and 4.1 ± 1.3 years respectively. There was no significant difference between groups at baseline. There was significant improvement in PI (p < 0.001) and PD (p < 0.001) at 12-weeks follow-up with respect to the baseline visit in both groups. There was a significant reduction in PI (p < 0.001) and PD (p < 0.001) for group-I as compared to group-II at follow-up. There was no statistically significant difference for BoP between groups at follow-up.ConclusionAntimicrobial PDT is more effective compared to MD alone in the treatment of p-iM in individuals vaping e-cigs. The findings of the present study should be considered preliminary and interpreted with caution. Further randomized clinical trials should be performed in order to obtain strong conclusions.
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Comment on: A Kidney Conundrum: More or Less?
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): Arjun Sahgal
http://ift.tt/2piMxGq
Predictors of Hypothyroidism in Hodgkin Lymphoma Survivors after Intensity-Modulated versus 3-Dimensional Radiation Therapy
Publication date: Available online 14 March 2018
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): Chelsea C. Pinnix, Laura Cella, Therese Y. Andraos, Zeina Ayoub, Sarah A. Milgrom, Jillian Gunther, Sonali Thosani, Christine Wogan, Manuel Conson, Vittoria D'Avino, Yasuhiro Oki, Michelle Fanale, Hun J. Lee, Sattva Neelapu, Luis Fayad, Frederick Hagemeister, M. Alma Rodriguez, Loretta J. Nastoupil, Yago Nieto, Wei Qiao, Roberto Pacelli, Bouthaina Dabaja
PurposeTo identify predictors of hypothyroidism after chemoradiation for Hodgkin lymphoma (HL) and to compare outcomes after intensity-modulated radiation therapy RT (IMRT) with those after 3-dimensional conformal RT (3D-CRT).Patients and MethodsNinety patients given involved-site IMRT in 2009–2014 were evaluated for treatment-induced hypothyroidism, defined as elevated thyroid-stimulating hormone (TSH) or decreased free thyroxine (fT4) levels or both. Receiver operating characteristic curve analysis identified individuals at low vs. high risk based on dosimetric variables. Dosimetric cutoff points were verified with an external dataset of 50 patients given 3D-CRT.ResultsMost patients given IMRT (75 [83%]) had stage II HL and the median prescribed dose was 30.6 Gy; in the 3D-CRT group 32 (64%) had stage II HL and the median prescribed dose was 32.0 Gy. No differences were found in proportions of patients with bilateral (P=0.982) or unilateral neck involvement (P=0.074) between either group. Hypothyroidism rates were marginally higher in the IMRT group, with estimated 3-year rates of freedom from hypothyroidism of 56.1% for the 3D-CRT group and 40% for the IMRT group (P=0.057). Univariate analysis showed that smaller thyroid volume and higher thyroid dose were associated with hypothyroidism in both groups (P<0.05). In the IMRT group, V25 and the absolute volume of thyroid spared from 25 Gy (VS25Gy) were the strongest predictors of hypothyroidism (P=0.001 and P<0.001). Cutoff points of 63.5% (V25) and 2.2 mL (VS25Gy) classified patients as high-risk (80%-82%) or low-risk (37%-44%) (P<0.001). Use of a thyroid avoidance structure reduced the incidence of hypothyroidism (P<0.05) in the IMRT group.ConclusionsThe percentage of thyroid receiving 25 Gy and the volume of thyroid spared from 25 Gy predicted risk of hypothyroidism after either IMRT or 3D-CRT for HL. IMRT may confer a higher risk than 3D-CRT unless a treatment avoidance structure is used during planning.
Teaser
In this comprehensive evaluation of risk factors associated with hypothyroidism after IMRT and involved-site RT for HL, identified variables included thyroid V25 and V30 and both absolute thyroid volume (cut point 11.2 mL) and volume spared from ≥25 Gy (≥2.2 mL). We further recommend contouring the thyroid and using thyroid avoidance structures in treatment planning when they do not compromise target coverage.http://ift.tt/2Iqz73J
The Children’s Oncology Group Radiation Oncology Discipline: 15 Years of Contribution to the Treatment of Childhood Cancer
Publication date: Available online 14 March 2018
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): John C. Breneman, Sarah S. Donaldson, Louis Constine, Thomas Merchant, Karen Marcus, Arnold Paulino, David Followill, Anita Mahajan, Nadia Laack, Natia Esiashvili, Daphne Haas-Kogan, Fran Laurie, Arthur Olch, Kenneth Ulin, David Hodgson, Torunn I. Yock, Stephanie Terezakis, Matt Krasin, Joseph Panoff, Paul Chuba, Chia-Ho Hua, Clayton B. Hess, Peter J. Houghton, Suzanne Wolden, Jeff Buchsbaum, Thomas J. Fitzgerald, John A. Kalapurakal
PurposeTo review the advances in radiation therapy for the management of pediatric cancers made by the Children's Oncology Group (COG) radiation oncology discipline since its inception in 2000.Methods and MaterialsThe various radiation oncology disease site leaders reviewed the contributions and advances in pediatric oncology made through the work of COG. They have presented outcomes of relevant studies and summarized current treatment policies developed by consensus from experts in the field.ResultsThe indications and techniques for pediatric radiation therapy have evolved considerably over the years for virtually all pediatric tumor types, resulting in improved cure rates together with the potential for decreased treatment-related morbidity and mortality.ConclusionsThe COG radiation oncology discipline has made significant contributions towards the treatment of childhood cancer. Our discipline is committed to continuing research to refine and modernize the use of radiation therapy in current and future protocols with the goal of further improving the cure rates and quality of life of children stricken with cancer.
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Editors, Issue sections
Publication date: February 2018
Source:Current Opinion in Immunology, Volume 50
http://ift.tt/2ItysOX
Contents, Cover details
Publication date: February 2018
Source:Current Opinion in Immunology, Volume 50
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Consolidative mechanisms of emotional processing in REM sleep and PTSD
Research suggests sleep plays a role in the consolidation of recently acquired memories for long-term storage. Rapid eye movement (REM) sleep has been shown to play a complex role in emotional-memory processing, and may be involved in subsequent waking-day emotional reactivity and amygdala responsivity. Interaction of the hippocampus and basolateral amygdala with the medial-prefrontal cortex is associated with sleep-dependent learning and emotional memory processing. REM is also implicated in post-traumatic stress disorder (PTSD), which is characterized by sleep disturbance, heightened reactivity to fearful stimuli, and nightmares.
http://ift.tt/2GtEEWL
A dataset of small molecules triggering transcriptional and translational cellular responses
Source:Data in Brief, Volume 17
Author(s): Mathilde Koch, Amir Pandi, Baudoin Delépine, Jean-Loup Faulon
The aim of this dataset is to identify and collect compounds that are known for being detectable by a living cell, through the action of a genetically encoded biosensor and is centred on bacterial transcription factors. Such a dataset should open the possibility to consider a wide range of applications in synthetic biology. The reader will find in this dataset the name of the compounds, their InChI (molecular structure), the publication where the detection was reported, the organism in which this was detected or engineered, the type of detection and experiment that was performed as well as the name of the biosensor. A comment field is also provided that explains why the compound was included in the dataset, based on quotes from the reference publication or the database it was extracted from. Manual curation of ACS Synthetic Biology abstracts (Volumes 1 to 6 and Volume 7 issue 1) was performed as well as extraction from the following databases: Bionemo v6.0 (Carbajosa et al., 2009) [1], RegTransbase r20120406 (Cipriano et al., 2013) [2], RegulonDB v9.0 (Gama-Castro et al., 2016) [3], RegPrecise v4.0 (Novichkov et al., 2013) [4] and Sigmol v20180122 (Rajput et al., 2016) [5].
http://ift.tt/2DsHLLn
Fluorescence microscopy data on expression of Paired Box Transcription Factor 7 in skeletal muscle of APOBEC2 knockout mice
Source:Data in Brief, Volume 17
Author(s): Hideaki Ohtsubo, Yusuke Sato, Yuji Matsuyoshi, Takahiro Suzuki, Wataru Mizunoya, Mako Nakamura, Ryuichi Tatsumi, Yoshihide Ikeuchi
The data presented in this article are related to the research articles entitled "APOBEC2 negatively regulates myoblast differentiation in muscle regeneration" and "Data supporting possible implication of APOBEC2 in self-renewal functions of myogenic stem satellite cells: toward understanding the negative regulation of myoblast differentiation" (Ohtsubo et al., 2017a, 2017b) [1,2]. This article provides in vivo phenotypical data to show that Paired Box Transcription Factor 7 (Pax7)-positive cell number (per myofiber) is significantly lower in APOBEC2 (a member of apoB mRNA editing enzyme, catalytic polypeptide-like family)-knockout muscle than the control wild-type tissue at the same age of 8-wk-old in mice. The emerging results support an essential role for APOBEC2 in the self-renewal functions of myogenic stem satellite cells, namely the re-establishment of quiescent status after activation and proliferation of myoblasts.
http://ift.tt/2GtFq5Q
The Implementation and First‐Round Results of a Community‐Based Colorectal Cancer Screening Program in Shanghai, China
AbstractBackground.The incidence and mortality rate of colorectal cancer (CRC) have increased dramatically over the past 3 decades in China due to changes in lifestyle factors. Early detection and treatment guidelines for asymptomatic cases have shown to improve CRC control in developed countries. In response to these challenges, the Shanghai Municipal Government launched a community‐based CRC screening program in 2012.Materials and Methods.Free initial screening, inclusive of immunochemical fecal occult blood and risk assessment (questionnaire), was provided by community health centers in Shanghai. Participants with positive results were referred to a specialist for a colonoscopy.Results.In 2013, 828,302 Shanghai residents were registered; 97.7% (809,528) of the registrants completed initial screening. Among 180,094 initial screening‐positive participants, 71,733 underwent colonoscopy. The proportion of compliance to colonoscopy was 39.8%; the proportion decreased with age and educational level. A total of 6,668 adenomas were detected, and 1,630 CRC cases were diagnosed. The CRC detection rate of the program was 201.35/100,000; among the detected CRCs, 51.6% were in stage 0–I.Conclusion.The screening program achieved great progress, especially on initial screening completion and CRC early stage rate, although particular intervention is still needed to improve the compliance of colonoscopy.Implications for Practice.Due to socioeconomic transitions and lifestyle changes, colorectal cancer is now becoming one of the most common cancers in developing countries, as it is in developed countries. While most developed countries have now initiated national colorectal cancer screening programs based on recommended country‐specific colorectal cancer screening guidelines, colonoscopy has become the most commonly used screening method. This is a challenge in developing countries due to limited resources. Based on the analysis of the Shanghai colorectal cancer screening program, with immunological fecal occult blood test and risk assessment as initial screening, followed by a diagnostic testing of colonoscopy for individuals with positive results, this article provides the basis and suggestion for similar program in other regions of China and other developing countries.
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Weekly Docetaxel, Cisplatin, and Cetuximab in Palliative Treatment of Patients with Squamous Cell Carcinoma of the Head and Neck
AbstractLessons Learned. Chemotherapy for recurrent, metastatic squamous cell carcinoma of the head and neck need not be known for extreme toxicity.The weekly regimen studied here has been demonstrated to be tolerable and effective.Background.The objective of this study was to establish the response rate, progression‐free survival (PFS) and overall survival (OS), and safety profile of weekly docetaxel, platinum, and cetuximab (TPC) in patients with relapsed or metastatic squamous cell carcinoma of the head and neck (SCCHN).Materials and Methods.Twenty‐nine patients with metastatic or recurrent SCCHN with an Eastern Cooperative Oncology Group (ECOG) performance status <3 were enrolled in an institutional review board‐approved phase II trial. This study permitted prior chemoradiation, radiation, and/or surgery, provided that 3 months had elapsed since the end of the potentially curative treatment. Patients received cisplatin 30 mg/m2 or carboplatin area under the curve (AUC) 2, docetaxel 30 mg/m2, and cetuximab 250 mg/m2 weekly for 3 weeks, followed by a break during the fourth week, for a 28‐day cycle. Planned intrapatient dose modifications were based on individual toxicity.Results.Twenty‐seven patients received TPC and were evaluable for response and toxicity. Rates of complete response (CR), partial response (PR), and confirmed PR were 3%, 52%, and 30%, respectively. The overall objective response rate was 56%. Estimated median PFS and OS were 4.8 and 14.7 months, respectively. The rates of grade 3 and 4 worst‐grade adverse events (AEs) per patient were 85% and 7%, respectively. Dose density through cycle 4 was preserved for all patients; however, treatment beyond cycle 6 with the TPC regimen proved unfeasible.Conclusion.Weekly docetaxel, cisplatin, and cetuximab is an effective regimen for patients with metastatic or recurrent SCCHN. Response rates, PFS, and OS compare favorably with other combination chemotherapy treatments. Grade 4 toxicity rates observed in this study were substantially lower than those described with regimens using less frequent, higher‐dose chemotherapy schedules.
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Hybrid Capture‐Based Comprehensive Genomic Profiling Identifies Lung Cancer Patients with Well‐Characterized Sensitizing Epidermal Growth Factor Receptor Point Mutations That Were Not Detected by Standard of Care Testing
AbstractBackground.In our recent study, of cases positive for epidermal growth factor receptor (EGFR) exon 19 deletions using comprehensive genomic profiling (CGP), 17/77 (22%) patients with prior standard of care (SOC) EGFR testing results available were previously negative for exon 19 deletion. Our aim was to compare the detection rates of CGP versus SOC testing for well‐characterized sensitizing EGFR point mutations (pm) in our 6,832‐patient cohort.Materials and Methods.DNA was extracted from 40 microns of formalin‐fixed paraffin‐embedded sections from 6,832 consecutive cases of non‐small cell lung cancer (NSCLC) of various histologies (2012–2015). CGP was performed using a hybrid capture, adaptor ligation‐based next‐generation sequencing assay to a mean coverage depth of 576×. Genomic alterations (pm, small indels, copy number changes and rearrangements) involving EGFR were recorded for each case and compared with prior testing results if available.Results.Overall, there were 482 instances of EGFR exon 21 L858R (359) and L861Q (20), exon 18 G719X (73) and exon 20 S768I (30) pm, of which 103 unique cases had prior EGFR testing results that were available for review. Of these 103 cases, CGP identified 22 patients (21%) with sensitizing EGFR pm that were not detected by SOC testing, including 9/75 (12%) patients with L858R, 4/7 (57%) patients with L861Q, 8/20 (40%) patients with G719X, and 4/7 (57%) patients with S768I pm (some patients had multiple EGFR pm). In cases with available clinical data, benefit from small molecule inhibitor therapy was observed.Conclusion.CGP, even when applied to low tumor purity clinical‐grade specimens, can detect well‐known EGFR pm in NSCLC patients that would otherwise not be detected by SOC testing. Taken together with EGFR exon 19 deletions, over 20% of patients who are positive for EGFR‐activating mutations using CGP are previously negative by SOC EGFR mutation testing, suggesting that thousands of such patients per year in the U.S. alone could experience improved clinical outcomes when hybrid capture‐based CGP is used to inform therapeutic decisions.Implications for Practice.This study points out that genomic profiling, as based on hybrid capture next‐generation sequencing, can identify lung cancer patients with point mutation in epidermal growth factor receptor (EGFR) missed by standard molecular testing who can likely benefit from anti‐EGFR targeted therapy. Beyond the specific findings regarding false‐negative point mutation testing for EGFR, this study highlights the need for oncologists and pathologists to be cognizant of the performance characteristics of testing deployed and the importance of clinical intuition in questioning the results of laboratory testing.
http://ift.tt/2FU8Tbe
Recent progress on the photocatalysis of carbon dots: Classification, mechanism and applications
Publication date: Available online 12 March 2018
Source:Nano Today
Author(s): Mei Han, Shoujun Zhu, Siyu Lu, Yubin Song, Tanglue Feng, Songyuan Tao, Junjun Liu, Bai Yang
With the rapid development of science and technology, environmental pollution and energy shortage become more and more prominent. To solve these problems, photocatalytic technology is regarded as one of the most efficient methods, allowing for both pollutant degradation and energy conversion. Compared with traditional group IIVI, IIIV quantum dots (QDs), carbon dots (CDs), as a newly emerging kind of fluorescent carbon-based material, possess many excellent properties, such as high aqueous solubility, low cost, low toxicity, abundant surface functional groups and good biocompatibility. In particular, the unique up-converted photoluminescence (PL) behavior and photo-induced electron transfer ability of CDs provide the new route to achieve efficient metal-free photocatalysts. This article reviews recent progress on CDs utilized for photocatalysis from different perspectives, including the following three parts: classification and synthesis, mechanism of CDs-derived photocatalysts as well as the applications for environmental issues (up-converted PL process) and energy conversion (photo-induced electron transfer process).
Graphical abstract
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Recent advances in functional nanomaterials for light–triggered cancer therapy
Publication date: Available online 13 March 2018
Source:Nano Today
Author(s): Shili Gai, Guixin Yang, Piaoping Yang, Fei He, Jun Lin, Dayong Jin, Bengang Xing
Photo–triggered therapeutic modalities for cancer have attracted enormous attention in recent years due to the easily focused and tuned properties of irradiation light that enable the localized treatment with non–invasive, direct and accurate characteristics. In addition, by using new developed functional nanomaterials, different therapeutic modalities can be integrated into a single platform, and co–therapies with dramatically enhanced anti–cancer ability by synergetic therapeutic effects are obtained. In the view of the fast development of anti–cancer strategy, we present an in–depth review of major breakthroughs in recent advanced functional nanomaterials for photo–triggered therapy. This review first summarizes the organic and inorganic photosensitizers for photodynamic therapy (PDT), four kinds of photothermal materials for photothermal therapy (PTT), as well as photo–switchable molecules or photolabile chemical groups bonded materials for chemotherapy. For each part, the therapeutic materials, mechanisms, superiorities and typical representatives are examined extensively. Then, we systematically discuss the optimized multifunctional nanomaterials consist of the above materials for PTT/PDT co–therapy, PTT/chemo co–therapy, PDT/chemo co–therapy and radiotherapy–composed co–therapy etc. And the synergetic therapeutic mechanism, anti–cancer efficiency, safety and design of therapeutic materials are highlighted. Finally, we give an outlook of the future directions of the rapidly growing functional nanomaterials for photo–triggered therapy, and propose several associated challenges and potential solutions.
Graphical abstract
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Evolving Linear Chromosomes and Telomeres: A C-Strand-Centric View
Publication date: Available online 14 March 2018
Source:Trends in Biochemical Sciences
Author(s): Neal F. Lue
Recent studies have resulted in deeper understanding of a variety of telomere maintenance mechanisms as well as plausible models of telomere evolution. Often overlooked in the discussion of telomere regulation and evolution is the synthesis of the DNA strand that bears the 5′-end (i.e., the C-strand). Herein, I describe a scenario for telomere evolution that more explicitly accounts for the evolution of the C-strand synthesis machinery. In this model, CTC1-STN1-TEN1 (CST), the G-strand-binding complex that regulates primase-Pol α-mediated C-strand synthesis, emerges as a pivotal player and evolutionary link. Itself arising from RPA, CST not only coordinates telomere synthesis, but also gives rise to the POT1-TPP1 complex, which became part of shelterin and regulates telomerase in G-strand elongation.
http://ift.tt/2peJf6Y
Affimer Proteins: Theranostics of the Future?
Publication date: Available online 14 March 2018
Source:Trends in Biochemical Sciences
Author(s): Stuart Kyle
Affimer proteins can bind to a wide variety of target molecules. They can complement and represent a promising alternative to conventional antibodies as they can target molecules with high affinity, specificity, and stability. In addition, they can be selected and expressed in bacterial and mammalian systems. Affimer protein technology shows promise as a tool in the biologist's arsenal of the future in imaging, diagnostic, and therapeutic applications.
http://ift.tt/2IovwD8
Enacted stigma and felt stigma experienced by adults who stutter
Source:Journal of Communication Disorders
Author(s): Michael P. Boyle
PurposeThe aim of this study was to (1) document the experiences of enacted stigma (external stigma, experienced discrimination) and felt stigma (anticipation and expectation of discrimination or negative treatment by others) in adults who stutter, (2) investigate their relationships to each other, and (3) investigate their relationships to global mental health.MethodParticipants were 324 adults who stutter recruited from clinicians and self-help group leaders in the United States. Participants completed an anonymous web survey consisting of measures of enacted stigma, felt stigma, and global mental health. Data analysis focused on obtaining descriptive statistics for enacted stigma and felt stigma, and performing correlational analysis between these variables, and also between these variables and global mental health.ResultsMost participants reported experiencing several different forms of social devaluation and negative treatment from other people at some point in their lives (i.e., enacted stigma), although they rarely experienced these events during the past year. Most participants agreed that they anticipate future stigmatizing experiences (i.e., felt stigma). Enacted stigma in the past year demonstrated a significant positive relationship to felt stigma. Both enacted stigma in the past year and felt stigma demonstrated significant negative relationships with global mental health. Enacted stigma in the past year and felt stigma were unique predictors of participants' global mental health.ConclusionsPeople who stutter experience discrimination and social devaluation, and they anticipate future stigmatizing experiences. Both of these types of stigma, enacted and felt, are associated with reduced mental health. Assessment and therapy with adults who stutter should address these aspects of stuttering.
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Beliefs and Behavioural Intentions Towards Pharmacotherapy for Stuttering: A Survey of Adults Who Stutter
Source:Journal of Communication Disorders
Author(s): Allan McGroarty, Rebecca McCartan
PurposeAlthough considerable efforts have been made to investigate the effectiveness of pharmacological treatments for stuttering, little is known about how the stuttering community perceives these treatments. This study aimed to assess and quantify beliefs regarding pharmacotherapy for adults who stutter and to establish whether behavioural intentions to undertake treatment were related to these beliefs.MethodAn adapted version of the Beliefs about Medicine Questionnaire was completed by adults who stutter. Participants also reported perceptions of their stuttering including its overall impact, ratings of previous speech therapy, and behavioural intentions to initiate pharmacotherapy and speech therapy in future.ResultsNecessity and concern beliefs were distributed widely across the sample and in a pattern indicating a relatively balanced perception of the benefits and costs of medication prescribed specifically for stuttering. Of the study's measures, the necessity-concerns differential most strongly predicted the behavioural intention to initiate pharmacotherapy. The overall impact of stuttering predicted intentions to seek both pharmacotherapy and speech therapy. Participants reported the likelihood of pursuing pharmacotherapy and speech therapy in equal measure.ConclusionsThe theoretical model of medication representations appears to be a useful framework for understanding the beliefs of adults who stutter towards the medical treatment of their disorder. The findings of this study may be of interest to clinicians and researchers working in the field of stuttering treatment and to people who stutter considering pharmacotherapy.
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Perceived Listener Effort as an Outcome Measure for Disordered Speech
Source:Journal of Communication Disorders
Author(s): Kathleen F. Nagle, Tanya L. Eadie
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Thoughts on the American Board of Radiology Examinations and the Resident Experience in Radiation Oncology
Source:Practical Radiation Oncology
Author(s): Robert J. Amdur, W. Robert Lee
http://ift.tt/2FEWOaQ
Influence of dynamic flow conditions on adsorbed plasma protein corona and surface-induced thrombus generation on antifouling brushes
Source:Biomaterials, Volume 166
Author(s): Kai Yu, Paula Andruschak, Han Hung Yeh, Dana Grecov, Jayachandran N. Kizhakkedathu
The information regarding the nature of protein corona (and its changes) and cell binding on biomaterial surface under dynamic conditions is critical to dissect the mechanism of surface-induced thrombosis. In this manuscript, we investigated the nature of protein corona and blood cell binding in heparinized recalcified human plasma, platelet rich plasma and whole blood on three highly hydrophilic antifouling polymer brushes, (poly(N, N-dimethylacrylamide) (PDMA), poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) and poly[N-(2-hydroxypropyl) methacrylamide] (PHPMA) using an in vitro blood loop model at comparable arterial and venous flow, and static conditions. A fluid dynamics model was used initially to better understand the resulting flow patterns in a vertical channel containing the substrates to arrive at the placement of the substrates within the blood loop. The protein binding on the brush modified substrates was determined using ellipsometry, fluorescence microscopy and the nature of the protein corona was investigated using mass spectrometry based proteomics. The flow elevated fouling on brush coated surface from blood. The extent of plasma protein adsorption and platelet adhesion onto PDMA brush was lower than other surfaces in both static and flow conditions. The profiles of adsorbed protein corona showed strong dependence on the test conditions (static vs. flow), and the chemistry of the polymer brushes. Specially, the PDMA brush under flow conditions was more enriched with coagulation proteins, complement proteins, vitronectin and fibronectin but was less enriched with serum albumin. Apolipoprotein B-100 and complement proteins were the most abundant proteins seen on PMPC and PHPMA surfaces under both flow and static conditions, respectively. Unlike PDMA brush, the flow conditions did not affect the composition of protein corona on PMPC and PHPMA brushes. The nature of the protein corona formed in flow conditions influenced the platelet and red blood cell binding. The dependence of shear stress on platelet adhesion from platelet rich plasma and whole blood highlights the contribution of red blood cells in enhancing platelet adhesion on the surface under high shear condition.
http://ift.tt/2GuqxR5
Stem cell derived phenotypic human neuromuscular junction model for dose response evaluation of therapeutics
Source:Biomaterials, Volume 166
Author(s): Navaneetha Santhanam, Lee Kumanchik, Xiufang Guo, Frank Sommerhage, Yunqing Cai, Max Jackson, Candace Martin, George Saad, Christopher W. McAleer, Ying Wang, Andrea Lavado, Christopher J. Long, James J. Hickman
There are currently no functional neuromuscular junction (hNMJ) systems composed of human cells that could be used for drug evaluations or toxicity testing in vitro. These systems are needed to evaluate NMJs for diseases such as amyotrophic lateral sclerosis, spinal muscular atrophy or other neurodegenerative diseases or injury states. There are certainly no model systems, animal or human, that allows for isolated treatment of motoneurons or muscle capable of generating dose response curves to evaluate pharmacological activity of these highly specialized functional units. A system was developed in which human myotubes and motoneurons derived from stem cells were cultured in a serum-free medium in a BioMEMS construct. The system is composed of two chambers linked by microtunnels to enable axonal outgrowth to the muscle chamber that allows separate stimulation of each component and physiological NMJ function and MN stimulated tetanus. The muscle's contractions, induced by motoneuron activation or direct electrical stimulation, were monitored by image subtraction video recording for both frequency and amplitude. Bungarotoxin, BOTOX® and curare dose response curves were generated to demonstrate pharmacological relevance of the phenotypic screening device. This quantifiable functional hNMJ system establishes a platform for generating patient-specific NMJ models by including patient-derived iPSCs.
http://ift.tt/2FHUDiD
Interventional Radiation Oncology (IRO): Transition of a magnetic resonance simulator to a brachytherapy suite
Source:Brachytherapy
Author(s): Roberta Anderson, Elwood Armour, Courtney Beeckler, Valerie Briner, Amanda Choflet, Andrea Cox, Amanda N. Fader, Marie N. Hannah, Robert Hobbs, Ellen Huang, Marilyn Kiely, Junghoon Lee, Marc Morcos, Paige E. McMillan, Dave Miller, Sook Kien Ng, Rashmi Prasad, Annette Souranis, Robert Thomsen, Theodore L. DeWeese, Akila N. Viswanathan
PurposeAs a core component of a new gynecologic cancer radiation program, we envisioned, structured, and implemented a novel Interventional Radiation Oncology (IRO) unit and magnetic resonance (MR)–brachytherapy environment in an existing MR simulator.Methods and MaterialsWe describe the external and internal processes required over a 6-8 month time frame to develop a clinical and research program for gynecologic brachytherapy and to successfully convert an MR simulator into an IRO unit.ResultsSupport of the institution and department resulted in conversion of an MR simulator to a procedural suite. Development of the MR gynecologic brachytherapy program required novel equipment, staffing, infrastructural development, and cooperative team development with anesthetists, nurses, therapists, physicists, and physicians to ensure a safe and functional environment. Creation of a separate IRO unit permitted a novel billing structure.ConclusionsThe creation of an MR-brachytherapy environment in an MR simulator is feasible. Developing infrastructure includes several collaborative elements. Unique to the field of radiation oncology, formalizing the space as an Interventional Radiation Oncology unit permits a sustainable financial structure.
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New findings confirm the viscoelastic behaviour of the inter-lamellar matrix of the disc annulus fibrosus in radial and circumferential directions of loading
Publication date: Available online 14 March 2018
Source:Acta Biomaterialia
Author(s): J. Tavakoli, J.J. Costi
While few studies have improved our understanding of composition and organization of elastic fibres in the inter-lamellar matrix (ILM), its clinical relevance is not fully understood. Moreover, no studies have measured the direct tensile and shear failure and viscoelastic properties of the ILM. Therefore, the aim of this study was, for the first time, to measure the viscoelastic and failure properties of the ILM in both the tension and shear directions of loading. Using an ovine model, isolated ILM samples were stretched to 40% of their initial length at three strain rates of 0.1%s-1 (slow), 1%s-1 (medium) and 10%s-1 (fast) and a ramp test to failure was performed at a strain rate of 10%s-1. The findings from this study identified that the stiffness of the ILM was significantly larger at faster strain rates, and energy absorption significantly smaller, compared to slower strain rates, and the viscoelastic and failure properties were not significantly different under tension and shear loading. We found a strain rate dependent response of the ILM during dynamic loading, particularly at the fastest rate. The ILM demonstrated a significantly higher capability for energy absorption at slow strain rates compared to medium and fast strain rates. A significant increase in modulus was found in both loading directions and all strain rates, having a trend of larger modulus in tension and at faster strain rates. The finding of no significant difference in failure properties in both loading directions, was consistent with our previous ultra-structural studies that revealed a well-organized (±45°) elastic fibre orientation in the ILM. The results from this study can be used to develop and validate finite element models of the AF at the tissue scale, as well as providing new strategies for fabricating tissue engineered scaffolds.Statement of significanceWhile few studies have improved our understanding of composition and organization of elastic fibres in the inter-lamellar matrix (ILM) of the annulus in the disc no studies have measured the direct mechanical failure and viscoelastic properties of the ILM. The findings from this study identified that the stiffness of the ILM was significantly larger at faster strain rates, and energy absorption significantly smaller, compared to slower strain rates. The failure properties of the ILM were not significantly different under tension and shear.
Graphical abstract
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Heparin functionalization increases retention of TGF-β2 and GDF5 on biphasic silk fibroin scaffolds for tendon/ligament-to-bone tissue engineering
Publication date: Available online 14 March 2018
Source:Acta Biomaterialia
Author(s): Sònia Font Tellado, Silvia Chiera, Walter Bonani, Patrina S.P. Poh, Claudio Migliaresi, Antonella Motta, Elizabeth R. Balmayor, Martijn van Griensven
The tendon/ligament-to-bone transition (enthesis) is a highly specialized interface tissue with structural gradients of extracellular matrix composition, collagen molecule alignment and mineralization. These structural features are essential for enthesis function, but are often not regenerated after injury. Tissue engineering is a promising strategy for enthesis repair. Engineering of complex tissue interfaces such as the enthesis is likely to require a combination of biophysical, biological and chemical cues to achieve functional tissue regeneration. In this study, we cultured human primary adipose-derived mesenchymal stem cells (AdMCs) on biphasic silk fibroin scaffolds with integrated anisotropic (tendon/ligament-like) and isotropic (bone/cartilage like) pore alignment. We functionalized those scaffolds with heparin and explored their ability to deliver transforming growth factor β2 (TGF-β2) and growth/differentiation factor 5 (GDF5). Heparin functionalization increased the amount of TGF-β2 and GDF5 remaining attached to the scaffold matrix and resulted in biological effects at low growth factor doses. We analyzed the combined impact of pore alignment and growth factors on AdMSCs. TGF-β2 and pore anisotropy synergistically increased the expression of tendon/ligament markers and collagen I protein content. In addition, the combined delivery of TGF-β2 and GDF5 enhanced the expression of cartilage markers and collagen II protein content on substrates with isotropic porosity, whereas enthesis markers were enhanced in areas of mixed anisotropic/isotropic porosity. Altogether, the data obtained in this study improves current understanding on the combined effects of biological and structural cues on stem cell fate and presents a promising strategy for tendon/ligament-to-bone regeneration.Statement of significanceRegeneration of the tendon/ligament-to-bone interface (enthesis) is of significance in the repair of ruptured tendons/ligaments to bone to improve implant integration and clinical outcome. This study proposes a novel approach for enthesis regeneration based on a biomimetic and integrated tendon/ligament-to-bone construct, stem cells and heparin-based delivery of growth factors. We show that heparin can keep growth factors local and biologically active at low doses, which is critical to avoid supraphysiological doses and associated side effects. In addition, we identify synergistic effects of biological (growth factors) and structural (pore alignment) cues on stem cells. These results improve current understanding on the combined impact of biological and structural cues on the multi-lineage differentiation capacity of stem cells for regenerating complex tissue interfaces.
Graphical abstract
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Effects of the spatial resolution of urban drainage data on nonpoint source pollution prediction
Abstract
Detailed urban drainage data are important for urban nonpoint source (NPS) pollution prediction. However, the difficulties in collecting complete pipeline data usually interfere with urban NPS pollution studies, especially in large-scale study areas. In this study, NPS pollution models were constructed for a typical urban catchment using the SWMM, based on five drainage datasets with different resolution levels. The influence of the data resolution on the simulation results was examined. The calibration and validation results of the higher-resolution (HR) model indicated a satisfactory model performance with relatively detailed drainage data. However, the performances of the parameter-regionalized lower-resolution (LR) models were still affected by the drainage data scale. This scale effect was due not only to the pipe routing process but also to changes in the effective impervious area, which could be limited by a scale threshold. The runoff flow and NPS pollution responded differently to changes in scale, primarily because of the difference between buildup and washoff and the more significant decrease in pollutant infiltration loss and the much greater increase of pollutant flooding loss while scaling up. Additionally, scale effects were also affected by the rainfall type. Sub-area routing between impervious and pervious areas could improve the LR model performances to an extent, and this approach is recommended to offset the influence of spatial resolution deterioration.
http://ift.tt/2tNGVcD
Decadal changes in surface ozone at the tropical station Thiruvananthapuram (8.542° N, 76.858° E), India: effects of anthropogenic activities and meteorological variability
Abstract
This paper presents the first observational results from an Indian station on the long-term changes in surface ozone (O3)—a major environmental pollutant and green house gas—over a period of about 40 years. It is based on the in situ measurements carried out during 1973–1975, 1983–1985, 1997–1998 and 2004–2014 at the tropical coastal station, Thiruvananthapuram. From 1973 to 1997, surface O3 shows a slow increase of ~ 0.1 ppb year−1 and a faster increase of 0.4 ppb year−1 afterwards till 2009 after which it showed a levelling off till 2012 followed by a minor decrease. The highest rate of increase is observed during 2005 to 2009 (2 ppb year−1), and the overall increase from 1973 to 2012 is ~ 10 ppb. The increase in day time O3 (peak O3) is estimated as 0.42 ppb year−1 during 1997–2012 and 2.93 ppb year−1 during 2006–2012. Interestingly, the long-term trend in O3 showed seasonal dependence which is more pronounced during O3 peaking seasons (winter/summer). The observed trends were analysed in the light of the changes in NO2, a major outcome of anthropogenic activities and methane which has both natural and anthropogenic sources and also meteorological parameters. Surface O3 and NOx exhibited positive association, but with varying rate of increase of O3 for NOx < 4 and > 4 ppb. Methane, a precursor of O3 also showed increase in tune with O3. Unlike many other high-latitude locations, meteorology plays a significant role in the long-term trends in O3 at this tropical site with water vapour abundance and strong solar irradiance which favour photochemistry. A comparison with the corresponding changes in the satellite-retrieved tropospheric column O3 (TCO) also showed an increase of 0.03 DU year−1 during 1996–2005 which enhanced to 0.12 DU year−1 after 2005. Both surface O3 and satellite-retrieved TCO were positively correlated with daily maximum temperature, increasing at the rate of 1.54 ppb °C−1 and 1.9 DU °C−1, respectively, on yearly basis. Surface O3 is found to be negatively correlated with water vapour content (ρv) at this tropical site, but at higher levels of ρv, O3 shows a positive trend.
http://ift.tt/2GuFkuI
Effects of silver nanoparticles on stress biomarkers of Channa striatus : immuno-protective or toxic?
Abstract
Nanotechnology is a novel arena with promising applications in the field of medicine, industry, and agriculture including fisheries. Cross-disciplinary interactions and the application of this technology in biological systems have led to the innovation of novel nanoparticle antioxidants, which are the subject of our study. In context with above background, we designed an experiment on nano-silver to elucidate its role for mitigation of abiotic and biotic stress. Three diets were formulated viz. silver nanoparticles (Ag-NPs) incorporated at 0.5 and 1 mg/kg diet and control diet (Ag-NPs at 0 mg/kg). Fish were exposed to sublethal level of 1/25th of LC50 (4 ppm) of lead (Pb) and temperature at 34 °C. The effect of Ag-NPs on productive performance (weight gain %, feed conversion ratio, protein efficiency ratio, and specific growth rate), stress biomarkers (catalase, super oxide dismutase, glutathione-s-transferase, acetylcholine esterase, cortisol, heat shock protein), biochemical and immunological response (protein and carbohydrate metabolic enzymes, phagocytic activity, serum total protein and albumin: globulin ratio), histopathology alterations in the liver and gill as well as survival of Channa striatus, following challenge with pathogenic bacteria were evaluated. Dietary Ag-NPs at 0.5-mg supplementation improved growth performance, immunity, survival, and reduced stress biomarker such as HSP 70, cortisol, and blood glucose in various fish tissues. Exposure to Pb and high temperature and group fed with Ag-NPs (1 mg/kg diet) demonstrated remarkable changes in the histo-architect of liver such as pyknotic nuclei, pyknosis, leucocyte infiltration, hemorrhage and karyokinesis, blood vessels with nucleated, lipid vacuoles in the liver tissue. Histology of gill displayed hyperplasia, aneurism, blood congestion, severe telengiectiasis, epithelial lifting, curling of secondary lamella, hyperplasia of epithelial cell of secondary lamella in the group exposed to lead and high temperature and supplemented with Ag-NPs at 1 mg/kg diet. In addition to histopathology, feeding with Ag-NPs at 1 mg/kg diet deteriorated and altered all studied parameters including reduced growth performance. Results obtained in the present study suggest that supplementation of Ag-NPs at 0.5 mg/kg diet has a definitive role to play in the mitigation of abiotic and biotic stress in C. striatus.
http://ift.tt/2tKE6sG
Oxidants produced by Methylglyoxal-modified Collagen Trigger ER Stress and Apoptosis in Skin Fibroblasts
Publication date: Available online 14 March 2018
Source:Free Radical Biology and Medicine
Author(s): Kerstin Nowotny, José Pedro Castro, Martín Hugo, Sabine Braune, Daniela Weber, Marc Pignitter, Veronika Somoza, Julia Bornhorst, Tanja Schwerdtle, Tilman Grune
Methylglyoxal (MG), a highly reactive dicarbonyl, interacts with proteins to form advanced glycation end products (AGEs). AGEs include a variety of compounds which were shown to have damaging potential and to accumulate in the course of different conditions such as diabetes mellitus and aging. After confirming collagen as a main target for MG modifications in vivo within the extracellular matrix, we show here that MG-collagen disrupts fibroblast redox homeostasis and induces endoplasmic reticulum (ER) stress and apoptosis. In particular, MG-collagen-induced apoptosis is associated with the activation of the PERK-eIF2α pathway and caspase-12. MG-collagen contributes to altered redox homeostasis by directly generating hydrogen peroxide and oxygen-derived free radicals. The induction of ER stress in human fibroblasts was confirmed using collagen extracts isolated from old mice in which MG-derived AGEs were enriched. In conclusion, MG-derived AGEs represent one factor contributing to diminished fibroblast function during aging.
Graphical abstract
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The biological age linked to oxidative stress modifies breast cancer aggressiveness
Publication date: Available online 14 March 2018
Source:Free Radical Biology and Medicine
Author(s): María del Mar Sáez Freire, Adrián Blanco Gómez, Sonia Castillo Lluva, Aurora Gómez Vecino, Julie Milena Galvis Jiménez, Carmen Martín Seisdedos, María Isidoro García, Lourdes Hontecillas Prieto, María Begoña García-Cenador, Francisco Javier García Criado, María Carmen Patino Alonso, Purificación Galindo Villardón, Jian-Hua Mao, Carlos Prieto, Andrés Castellanos Martín, Lars Kaderali, Jesús Pérez Losada
The incidence of breast cancer increases with age until menopause, and breast cancer is more aggressive in younger women. The existence of epidemiological links between breast cancer and aging indicates that both processes share some common mechanisms of development. Oxidative stress is associated with both cancer susceptibility and aging. Here we observed that ERBB2-positive breast cancer, which developed in genetically heterogeneous ERBB2-positive transgenic mice generated by a backcross, is more aggressive in chronologically younger than in older mice (differentiated by the median survival of the cohort that was 79 weeks), similar to what occurs in humans. In this cohort, we estimated the oxidative biological age using a mathematical model that integrated several subphenotypes directly or indirectly related to oxidative stress. The model selected the serum levels of HDL-cholesterol and magnesium and total AKT1 and glutathione concentrations in the liver. The grade of aging was calculated as the difference between the predicted biological age and the chronological age. This comparison permitted the identification of biologically younger and older mice compared with their chronological age. Interestingly, biologically older mice developed more aggressive breast cancer than the biologically younger mice. Genomic regions on chromosomes 2 and 15 linked to the grade of oxidative aging were identified. The levels of expression of Zbp1 located on chromosome 2, a gene related to necroptosis and inflammation, positively correlated with the grade of aging and tumour aggressiveness. Moreover, the pattern of gene expression of genes linked to the inflammation and the response to infection pathways was enriched in the livers of biologically old mice. This study shows part of the complex interactions between breast cancer and aging.
Graphical abstract
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Improved measurements of scant hydrogen peroxide enable experiments that define its threshold of toxicity for Escherichia coli
Publication date: Available online 14 March 2018
Source:Free Radical Biology and Medicine
Author(s): Xin Li, James A. Imlay
Escherichia coli is a model organism that has been exploited to reveal key details of hydrogen peroxide stress: the biomolecules that H2O2 most rapidly damages and the defensive tactics that organisms use to fend it off. Much less clear is the amount of exogenous H2O2 that is sufficient to injure the bacterium and/or to trigger its stress response. To fill this gap, we need to study the behavior of cells when they are exposed to defined amounts of H2O2 on an hours-long time scale. Such experiments are difficult because bacteria rapidly consume H2O2 that is added to test cultures. Further, lab media itself can generate H2O2, and media components interfere with the quantification of H2O2 levels. In this study we describe mechanisms by which media components interfere with H2O2 determinations, and we identify simple ways to minimize and correct for this interference. Using these techniques, it was shown that standard media generate so much H2O2 that most intracellular H2O2 derives from the medium rather than from endogenous metabolism. Indeed, bacteria spread on plates must induce their stress response or else perish. Finally, two straightforward methods were used to sustain low-micromolar steady-state concentrations of H2O2. In this way we determined that > 2 μM extracellular H2O2 is sufficient to trigger the intracellular OxyR stress response, and > 5 μM begins to impair cell growth in a minimal medium. These concentrations are orders of magnitude lower than the doses that have typically been used in lab experiments. The new approaches should enable workers to study how various organisms cope with natural levels of H2O2 stress.
Graphical abstract
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Potential mechanisms underlying cardiovascular protection by polyphenols: Role of the endothelium
Publication date: Available online 13 March 2018
Source:Free Radical Biology and Medicine
Author(s): Min-Ho Oak, Cyril Auger, Eugenia Belcastro, Sin-Hee Park, Hyunho Lee, Valérie B. Schini-Kerth
Epidemiological studies have indicated that regular intake of polyphenol-rich diets such as red wine and tea, are associated with a reduced risk of cardiovascular diseases. The beneficial effect of polyphenol-rich products has been attributable, at least in part, to their direct action on the endothelial function. Indeed, polyphenols from tea, grapes, cacao, berries, and plants have been shown to activate endothelial cells to increase the formation of potent vasoprotective factors including nitric oxide (NO) and to delay endothelial ageing. Moreover, intake of such polyphenol-rich products has been associated with the prevention and/or the improvement of an established endothelial dysfunction in several experimental models of cardiovascular diseases and in Humans with cardiovascular diseases. This review will discuss both experimental and clinical evidences indicating that polyphenols are able to promote endothelial and vascular health, as well as the underlying mechanisms.
Graphical abstract
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Effect of Flavoring Chemicals on Free Radical Formation in Electronic Cigarette Aerosols
Publication date: Available online 13 March 2018
Source:Free Radical Biology and Medicine
Author(s): Zachary T. Bitzer, Reema Goel, Samantha M. Reilly, Ryan J. Elias, Alexey Silakov, Jonathan Foulds, Joshua Muscat, John P. Richie
BackgroundFlavoring chemicals, or flavorants, have been used in electronic cigarettes (e-cigarettes) since their inception; however, little is known about their toxicological effects. Free radicals present in e-cigarette aerosols have been shown to induce oxidative stress resulting in damage to proliferation, survival, and inflammation pathways in the cell. Aerosols generated from e-liquid solvents alone contain high levels of free radicals but few studies have looked at how these toxins are modulated by flavorants.ObjectivesWe investigated the effects of different flavorants on free radical production in e-cigarette aerosols.MethodsFree radicals generated from 49 commercially available e-liquid flavors were captured and analyzed using electron paramagnetic resonance (EPR). The flavorant composition of each e-liquid was analyzed by gas chromatography mass spectroscopy (GCMS). Radical production was correlated with flavorant abundance. Ten compounds were identified and analyzed for their impact on free radical generation.ResultsNearly half of the flavors modulated free radical generation. Flavorants with strong correlations included β-damascone, δ-tetradecalactone, γ-decalactone, citral, dipentene, ethyl maltol, ethyl vanillin, ethyl vanillin PG acetal, linalool, and piperonal. Dipentene, ethyl maltol, citral, linalool, and piperonal promoted radical formation in a concentration-dependent manner. Ethyl vanillin inhibited the radical formation in a concentration dependent manner. Free radical production was closely linked with the capacity to oxidize biologically-relevant lipids.ConclusionsOur results suggest that flavoring agents play an important role in either enhancing or inhibiting the production of free radicals in flavored e-cigarette aerosols. This information is important for developing regulatory strategies aimed at reducing potential harm from e-cigarettes.
Graphical abstract
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Oxidative stress and mitochondrial adaptive shift during pituitary tumoral growth
Publication date: Available online 13 March 2018
Source:Free Radical Biology and Medicine
Author(s): Maria Eugenia Sabatino, Ezequiel Grondona, Liliana d.V. Sosa, Bethania Mongi Bragato, Lucia Carreño, Virginia Juarez, Rodrigo A. da Silva, Aline Remor, Lucila de Bortoli, Roberta de Paula Martins, Pablo A. Pérez, Juan Pablo Petiti, Silvina Gutiérrez, Alicia I. Torres, Alexandra Latini, Ana L. De Paul
The cellular transformation of normal functional cells to neoplastic ones implies alterations in the cellular metabolism and mitochondrial function in order to provide the bioenergetics and growth requirements for tumour growth progression. Currently, the mitochondrial physiology and dynamic shift during pituitary tumour development are not well understood. Pituitary tumors present endocrine neoplastic benign growth which, in previous reports, we had shown that in addition to increased proliferation, these tumours were also characterized by cellular senescence signs with no indication of apoptosis. Here, we show clear evidence of oxidative stress in pituitary cells, accompanied by bigger and round mitochondria during tumour development, associated with augmented biogenesis and an increased fusion process. An activation of the Nrf2 stress response pathway together with the attenuation of the oxidative damage signs occurring during tumour development were also observed which will probably provide survival advantages to the pituitary cells. These neoplasms also presented a progressive increase in lactate production, suggesting a metabolic shift towards glycolysis metabolism. These findings might imply an oxidative stress state that could impact on the pathogenesis of pituitary tumours. These data may also reflect that pituitary cells can modulate their metabolism to adapt to different energy requirements and signaling events in a pathophysiological situation to obtain protection from damage and enhance their survival chances. Thus, we suggest that mitochondria function, oxidative stress or damage might play a critical role in pituitary tumour progression.
Graphical abstract
http://ift.tt/2IsJIv2
Clinical Characteristics of Pediatric Optic Neuritis with Myelin Oligodendrocyte Glycoprotein Seropositive: a Cohort Study
Source:Pediatric Neurology
Author(s): Qian Chen, Guixian Zhao, Yongheng Huang, Zhenxin Li, Xinghuai Sun, Ping Lu, Yan S, Min Wang, Guohong Tian
BackgroundThe clinical characteristics of pediatric optic neuritis (ON) patients with seropositive myelin oligodendrocyte glycoprotein (MOG) antibodies in Asian have not been reported.Main proceduresAcute onset ON patients ≤ 18-years-old were enrolled.Serum MOG and aquaporin-4 (AQP4) antibodies were detected and patients were followed-up for at least 6 months. The demographic, clinical and radiological features, together with optical coherence tomography (OCT) were evaluated among MOG-seropositive ON (MOG-ON), AQP4-seropositive ON (AQP4-ON) and double seronegative ON (seronegative-ON). Best corrected visual acuity (BCVA), thickness of optic disc retinal nerve fiber layer (RNFL) and macular ganglion cell complex (GCC) measured by OCT at 6 months after an acute attack. The clinical features in MOG seropositive pediatric ON were compared with other phenotypes.Main findingsAmong MOG-ON (n=10, eyes=19), AQP4-ON (n=9, eyes=15) and seronegative-ON (n=40, eyes=62), the percentages of BCVA measured better than 0.8 (20/25) at the 6-month visit were 89.47%, 33.33% and 82.26% respectively, which were significantly better in MOG-ON and seronegative-ON patients than that of AQP4-ON patients (p=0.02). The average peripapillary RNFL were 58.03±8.73µm, 64.34±12.88µm and 78.12±13.34µm for the MOG-ON, AQP4-ON and seronegative-ON patients respectively, which showed no statistic difference between MOG-ON and AQP4-ON patients (p=0.089), but were both thinner than seronegative-ON patients (p=0.001).ConclusionsThe recovery of visual acuity in MOG-ON patients was as good as in seronegative-ON patients, and the RNFL of the optic nerve head showed thinning as severe as the AQP4-ON patients.
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Nutritional analysis of Spirulina dietary supplements: Optimization procedure of ultrasound-assisted digestion for multielemental determination
Publication date: 15 August 2018
Source:Food Chemistry, Volume 257
Author(s): Bárbara D. Neher, Silvana M. Azcarate, José M. Camiña, Marianela Savio
Arthrospira platensis and Arthrospira maxima are a type of blue-green microalga used as a dietary supplement (Spirulina). A low time-consuming ultrasound-assisted digestion (UAD) of Spirulina supplements for multielemental determination by microwave induced plasma atomic emission spectrometry (MPAES) was performed. Several parameters such as acid concentration (AC), thermostated water bath (TWB), digestion time (DT) and UAD – probe or bath – affecting the digestion process were evaluated through a full factorial design. Under the optimal conditions −100 °C for TWB, 5% for AC and 10 min for DT- and selecting the bath as the proper UAD system, the concentrations of 15 analytes (Al, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, V, Zn) were reported. The values are in accordance with the recommendation established by Food and Drug Administration (FDA) excepting for Cd. The knowledge of Spirulina multielemental composition contributes to an outstanding nutritional and toxicological report for human health.
http://ift.tt/2tOuYn4
Influence of thickness and annealing on photoluminescence of nanostructured ZnSe/ZnS multilayer thin films prepared by electron beam evaporation
Publication date: July 2018
Source:Journal of Luminescence, Volume 199
Author(s): Kai Ou, Shenwei Wang, Miaoling Huang, Yanwei Zhang, Yu Wang, Xiaoxia Duan, Lixin Yi
In this paper, nanostructured ZnSe/ZnS multilayer thin films were prepared on silicon substrates by electron beam evaporation technique. This heterostructure takes advantage of the properties of ZnSe and ZnS, with ZnSe and ZnS acting as light-emitting and passivation layers, respectively. To enhance the luminescence performance, the optimal thickness of ZnS and ZnSe films and the annealing conditions were investigated. Nanostructured films with 3.5 nm ZnSe and 15 nm ZnS annealed at 660 °C for 100 min in N2 were found to be the optimal conditions. In addition, crystal structures and surface morphologies of the films were characterized, which showed outstanding blue emission. The excellent blue emission achieved in the optimized films indicates that nanostructured ZnSe/ZnS multilayer films could be used as novel luminescence materials.
http://ift.tt/2GtdlvG
Two-phase homogeneous diffusion model for the fixed bed sorption of heavy metals on natural zeolites
Publication date: August 2018
Source:Microporous and Mesoporous Materials, Volume 266
Author(s): V.J. Inglezakis, M.M. Fyrillas, M.A. Stylianou
In this work, the fixed bed removal kinetics of Pb2+, Zn2+, Mn2+, Cr3+, Fe3+ and Cu2+ from aqueous solutions on natural zeolites was studied. For this aim, a non-dimensional two-phase homogeneous solid diffusion model including axial dispersion and equipped with a universal double-selectivity equilibrium model is developed and applied. In total 9 isotherms, representing 128 experimental points and 25 breakthrough curves, representing 764 experimental points are used in modeling. The application of the model is satisfactory resulted in an average deviation from the experimental data of 11.19 ± 5.53%. The solid phase diffusion coefficients are between 10−7 and 10−9 cm2/s depending on the metal, flow rate and particle size in the decreasing order of Cu > Fe, Cr > Zn, Pb > Mn. The study is supplemented by an extended literature review on fixed bed models and experimentally derived solid phase diffusion coefficients in zeolites.
Graphical abstract
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Boosting the efficiency of AgInSe2 quantum dot sensitized solar cells via core/shell/shell architecture
Publication date: 1 August 2018
Source:Solar Energy Materials and Solar Cells, Volume 182
Author(s): Mulu Alemayehu Abate, Jia-Yaw Chang
Interfacial engineering of the photoanode has been one of the most important strategies in designing high-performance quantum dot (QD)-sensitized solar cells (QDSSCs). In this work, we demonstrated a promising route to enhance the photovoltaic performance by inserting an additional CdS inner shell between AgInSe2 (AISe) QDs and a ZnS outer shell to obtain an AISe/CdS/ZnS core/shell/shell QDSSC. These double passivation shells prevent current leakage from the QDs to the electrolyte. The results of electrochemical impedance spectroscopy confirmed that the CdS/ZnS double passivation shell in the AISe QDSSC contributes greatly to suppression of charge recombination. As a result, the AISe QDSSC with CdS/ZnS double passivation shells exhibited a remarkably high conversion efficiency (6.27%), which is significantly higher than those of devices without a passivation shell (1.02%) and with CdS (4.37%) or ZnS (5.23%) single passivation shells. To the best of the authors' knowledge, this efficiency is one of the highest values obtained for an Ag-based QDSSC.
Graphical abstract
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In situ hydrothermal preparation of mesoporous Fe3O4 film for high-performance negative electrodes of supercapacitors
Publication date: 15 July 2018
Source:Microporous and Mesoporous Materials, Volume 265
Author(s): Ke Jiang, Baolong Sun, Mengqi Yao, Ni Wang, Wencheng Hu, Sridhar Komarneni
A mesoporous Fe3O4 film was prepared as binder-free electrode material for supercapacitors through a facile process that included the hydrothermal electroplating of an Fe/Zn alloy, in situ electrolytic dealloying to remove the Zn template, and oxidation in a water vapor environment. The Fe3O4 film showed a cubic structure and mesoporosity with a specific surface area of 247 m2 g−1. As a negative electrode material, the mesoporous Fe3O4 film delivered a high gravimetric capacity of 221 C g−1 at 1 A g−1, and the gravimetric capacity was maintained at 154 C g−1 even at a high current density of 50 A g−1. In addition, the mesoporous Fe3O4 electrode exhibited very high cycling stability (only 4.7% capacity loss after 10,000 galvanostatic charge–discharge cycles). Electrochemical impedance spectroscopy revealed that the mesoporous Fe3O4 film had excellent conductivity, implying its promising application as a supercapacitor electrode.
Graphical abstract
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Sonochemical synthesis and structural characterization of a new Zn(II) nanoplate metal–organic framework with removal efficiency of Sudan red and Congo red
Publication date: July 2018
Source:Ultrasonics Sonochemistry, Volume 45
Author(s): Nasrin Abdollahi, Mohammad Yaser Masoomi, Ali Morsali, Peter C. Junk, Jun Wang
A 3-D Zn(II) based metal–organic framework (MOF) of [Zn4(oba)3(DMF)2] was synthesized using the nonlinear dicarboxylate ligand, 4,4′-oxybis(benzoic acid) (H2oba) via sonochemical and solvothermal routes. IR spectroscopy, single-crystal X-ray crystallography, scanning electron microscopy, and X-ray powder diffraction were used to characterize these MOF samples. The effect of different times of irradiation and various concentrations of primary reagents were experimented for obtaining monotonous morphology. The results show that uniform nanoplates can be achieved by increasing the time of irradiation and decreasing the concentration. N2 adsorption was applied to examine the effect of synthesis method on porosity of the framework. Also Congo red and Sudan red dyes were employed to explore the efficiency of this MOF in removal of the dye pollutants.
http://ift.tt/2GtklbX
Neurophysiological processes and functional neuroanatomical structures underlying proactive effects of emotional conflicts
Source:NeuroImage, Volume 174
Author(s): Marie Luise Schreiter, Witold Chmielewski, Christian Beste
There is a strong inter-relation of cognitive and emotional processes as evidenced by emotional conflict monitoring processes. In the cognitive domain, proactive effects of conflicts have widely been studied; i.e. effects of conflicts in the n-1 trial on trial n. Yet, the neurophysiological processes and associated functional neuroanatomical structures underlying such proactive effects during emotional conflicts have not been investigated. This is done in the current study combining EEG recordings with signal decomposition methods and source localization approaches.We show that an emotional conflict in the n-1 trial differentially influences processing of positive and negative emotions in trial n, but not the processing of conflicts in trial n. The dual competition framework stresses the importance of dissociable 'perceptual' and 'response selection' or cognitive control levels for interactive effects of cognition and emotion. Only once these coding levels were isolated in the neurophysiological data, processes explaining the behavioral effects were detectable. The data show that there is not only a close correspondence between theoretical propositions of the dual competition framework and neurophysiological processes. Rather, processing levels conceptualized in the framework operate in overlapping time windows, but are implemented via distinct functional neuroanatomical structures; the precuneus (BA31) and the insula (BA13). It seems that decoding of information in the precuneus, as well as the integration of information during response selection in the insula is more difficult when confronted with angry facial emotions whenever cognitive control resources have been highly taxed by previous conflicts.
http://ift.tt/2GrNwfr
Functional correlate and delineated connectivity pattern of human motion aftereffect responses substantiate a subjacent visual-vestibular interaction
Source:NeuroImage, Volume 174
Author(s): Ria Maxine Rühl, Thomas Bauermann, Marianne Dieterich, Peter zu Eulenburg
The visual motion aftereffect (MAE) is the most prominent aftereffect in the visual system. Regarding its function, psychophysical studies suggest its function to be a form of sensory error correction, possibly also triggered by incongruent visual-vestibular stimulation. Several observational imaging experiments have deducted an essential role for region MT+ in the perception of a visual MAE but not provided conclusive evidence. Potential confounders with the MAE such as ocular motor performance, attention, and vection sensations have also never been controlled for. Aim of this neuroimaging study was to delineate the neural correlates of MAE and its subjacent functional connectivity pattern.A rotational MAE (n = 22) was induced using differing visual stimuli whilst modulating ocular motor parameters in a 3T scanner. Data was analyzed with SPM12. Eye movements as a response to the same stimuli were studied by means of high-resolution videooculography.Analysis for all stimuli gave bilateral activations along the dorsal visual stream with an emphasis on area MT. The onset of a visual MAE revealed an additional response in the right medial superior temporal area (MST) and a concurrent deactivation of vestibular hub region OP2. There was no correlation for the BOLD effects during the MAE with either ocular motor or attention parameters.The functional correlate of a visual MAE in humans may be represented in the interaction between region MT and area MST. This MAE representation is independent of a potential afternystagmus, attention and the presence of egomotion sensations. Connectivity analyses showed that in the event of conflicting visual-vestibular motion information (here MAE) area MST and area OP2 may act as the relevant mediating network hubs.
http://ift.tt/2tJt9aI
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Summary Insulinomas are rare neuroendocrine tumours that classically present with fasting hypoglycaemia. This case report discusses an un...
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