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https://www.readbyqxmd.com/read/28098556/genetic-defects-in-%C3%AE-spectrin-and-tau-sensitize-c-elegans-axons-to-movement-induced-damage-via-torque-tension-coupling
#1
Michael Krieg, Jan Stühmer, Juan G Cueva, Richard Fetter, Kerri A Spliker, Daniel Cremers, Kang Shen, Alexander R Dunn, Miriam B Goodman
Our bodies are in constant motion and so are the neurons that invade each tissue. Motion-induced neuron deformation and damage are associated with several neurodegenerative conditions. Here, we investigated the question of how the neuronal cytoskeleton protects axons and dendrites from mechanical stress, exploiting mutations in UNC-70 β-spectrin, PTL-1 tau/MAP2-like and MEC-7 β-tubulin proteins in Caenorhabditis elegans. We found that mechanical stress induces supercoils and plectonemes in the sensory axons of spectrin and tau double mutants...
January 18, 2017: ELife
https://www.readbyqxmd.com/read/28098506/capsicum-annuum-var-grossum-bell-pepper-inhibits-%C3%AE-secretase-activity-and-%C3%AE-amyloid1-40-aggregation
#2
Omodesola Oluwafisayo Ogunruku, Ganiyu Oboh, Sabina Passamonti, Federica Trammer, Aline Augusti Boligon
The deposition of amyloid protein as senile plaques is the major signature of Alzheimer's disease (AD). It is produced by the sequential cleavage of the amyloid precursor protein by secretases. Moreover, peppers are noted for their antiaging and cognitive enhancing properties. Thus, in this study, the effects of polyphenol-rich extracts from bell pepper on amyloid production and aggregation in vitro were investigated. Bell pepper (ripe and unripe) was extracted with methanol-1 N HCl (1:1 v/v). Thereafter, the inhibitory potentials of the extracts on β-secretase and β-amyloid1-40 aggregation were determined...
January 18, 2017: Journal of Medicinal Food
https://www.readbyqxmd.com/read/28098491/particle-sizing-methods-for-the-detection-of-protein-aggregates-in-biopharmaceuticals
#3
Akram Khodabandehloo, David Da Yong Chen
Protein aggregation is a common biological phenomenon which is responsible for degenerative diseases and is problematic in the pharmaceutical industry. According to the rules provided by regulatory agencies, industry is supposed to assess the product quality regarding the presence of subvisible particles. Also, they should evaluate the technologies that are used to measure these particles. Therefore, US FDA and industry have been looking for methods capable of accurately characterizing the protein products...
January 18, 2017: Bioanalysis
https://www.readbyqxmd.com/read/28098460/sulfate-mediated-end-to-end-assembly-of-gold-nanorods
#4
Seyyed Mohammad Hossein Abtahi, Nathan D Burrows, Fred A Idesis, Catherine J Murphy, Navid B Saleh, Peter J Vikesland
There is interest in the controlled aggregation of gold nanorods (GNRs) for the production of extended nanoassemblies. Prior studies have relied upon chemical modification of the GNR surface to achieve a desired final aggregate structure. Herein, we illustrate that control of electrolyte composition can facilitate end-to-end assembly of cetyltrimethylammonium bromide (CTAB) coated GNRs. By adjusting either the sulfate anion concentration or the exposure time it is possible to connect GNRs in chain-like assemblies...
January 18, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28098458/sequence-of-silicon-monolayer-structures-grown-on-a-ru-surface-from-a-herringbone-structure-to-silicene
#5
Li Huang, Yanfang Zhang, Yu-Yang Zhang, Wenyan Xu, Yande Que, En Li, Jinbo Pan, Yeliang Wang, Yunqi Liu, Shixuan Du, Sokrates T Pantelides, Hong-Jun Gao
Silicon-based two-dimensional (2D) materials are uniquely suited for integration in Si-based electronics. Silicene, an analog of graphene, was recently fabricated on several substrates and was used to make a field-effect transistor. Here, we report that, when Ru(0001) is used as a substrate, a range of distinct monolayer silicon structures forms, evolving towards silicene with increasing Si coverage. Low Si coverage produces a herringbone structure, a hitherto undiscovered 2D phase of silicon. With increasing Si coverage, herringbone elbows evolve into silicene-like honeycomb stripes under tension, resulting in a herringbone-honeycomb 2D superlattice...
January 18, 2017: Nano Letters
https://www.readbyqxmd.com/read/28098424/application-of-zein-modified-magnetite-nanoparticles-in-dispersive-magnetic-micro-solid-phase-extraction-of-synthetic-food-dyes-in-foodstuffs
#6
Azam Jangju, Khalil Farhadi, Mehdi Hatami, Samireh Amani, Farzan Esmali, Aisan Moshkabadi, Fatemeh Hajilari
A simple method for the simultaneous and trace analysis of four synthetic food azo dyes including carmoisine, ponceau 4R, sunset yellow and allura red from some foodstuff samples was developed by combining dispersive μ-solid-phase extraction and high-performance liquid chromatography with diode array detection. Zein-modified magnetic Fe3 O4 nanoparticles were prepared and used for μ-solid-phase extraction of trace amounts of mentioned food dyes. The prepared modified magnetic nanoparticles were characterized by scanning electron microscopy and FTIR spectroscopy...
January 18, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28098414/integrated-photo-grafted-molecularly-imprinted-polymers-with-a-cellulose-acetate-membrane-for-the-extraction-of-melamine-from-dry-milk-before-hplc-analysis
#7
Behrouz Akbari-Adergani, Gholam-Hossein Sadeghian, Alireza Alimohammadi, Zahra Esfandiari
In this study, a new separation technique based on membrane extraction is described for the determination of melamine in dry milk. The water-compatible cellulose acetate membrane, which is photo-grafted by melamine imprinted nanospheres, was prepared by placing the membrane into the polymerization solution containing methacrylic acid as functional monomer, ethylene glycol dimethacrylate as cross-linker, acetonitrile as porogen and melamine as the template molecule. The characterization of the polymeric membrane was performed by Fourier transmission infrared spectroscopy and scanning electron microscopy...
January 18, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28098343/mn-accumulation-in-a-submerged-plant-egeria-densa-hydrocharitaceae-is-mediated-by-epiphytic-bacteria
#8
Kousuke Tsuji, Takuma Asayama, Nozomi Shiraki, Shota Inoue, Erina Okuda, Chizuru Hayashi, Kazuma Nishida, Hiroshi Hasegawa, Emiko Harada
Many aquatic plants act as biosorbents, removing and recovering metals from the environment. To assess the biosorbent activity of Egeria densa, a submerged freshwater macrophyte, plants were collected monthly from a circular drainage area in Lake Biwa basin and the Mn concentrations of the plants were analyzed. Mn concentrations in these plants were generally above those of terrestrial hyperaccumulators, and were markedly higher in spring and summer than in autumn. Mn concentrations were much lower in plants incubated in hydroponic medium at various pH levels with and without Mn supplementation than in field-collected plants...
January 18, 2017: Plant, Cell & Environment
https://www.readbyqxmd.com/read/28098305/phase-behaviour-and-temperature-responsive-properties-of-a-gemini-surfactant-brij-30-water-system
#9
Chuanhong Han, Yan Guo, Xiaoxiao Chen, Meihuan Yao, Yingtian Zhang, Qirui Zhang, Xilian Wei
The phase behaviour of a ternary system composed of cationic gemini surfactant 2-hydroxypropyl-1,3-bis(myristyldimethylammonium chloride) (14-3(OH)-14(2Cl)), nonionic surfactant polyoxyethylene laurel ether (C12H25(OCH2CH2)10OH, Brij-30) and H2O was studied and its phase diagram was determined. In several different phase regions identified in the phase diagram, the viscoelastic worm-like micellar solution region was investigated. The focus of the investigation was the increase in the viscosity of the micellar solution with the temperature and the Brij-30 content, as suggested by a partial region of the triangular phase diagram...
January 18, 2017: Soft Matter
https://www.readbyqxmd.com/read/28098284/oxygen-vacancy-ordering-in-srfe0-25co0-75o2-63-perovskite-material
#10
Javier Fernández Sanjulián, Madhu Chennabasappa, Susana García-Martín, Gwilherm Nénert, Alain Wattiaux, Etienne Gaudin, Olivier Toulemonde
SrFe0.25Co0.75O2.63 was synthesized by a solid-state reaction. Its structural study at room temperature using conventional X-ray as well as neutron powder diffraction, electron diffraction and high-resolution transmission electron microscopy is presented. An oxygen-vacancy ordering related to the "314" model known for the Sr3Y1Co4O10.5 oxide is proposed despite neither an A-site ordering nor an A-site mismatch. By means of Mössbauer spectroscopy, Mohr salt titration and the difference in the neutron cross sections of Fe and Co, a cation distribution within the crystallographic sites as the following Sr4(Fe0...
January 18, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28098279/eu-3-doped-y3-xndxal3o12-garnet-synthesis-and-structural-investigation
#11
L Pavasaryte, A Katelnikovas, V Klimavicius, V Balevicius, A Krajnc, G Mali, J Plavec, A Kareiva
Nd(3+)-Doped yttrium aluminium garnet and Eu(3+)-Nd(3+)-co-doped yttrium aluminium garnet were synthesized using an environmentally friendly sol-gel method at low temperatures. The results of X-ray diffraction (XRD) analysis of the powders sintered at 1000 °C showed the purity and formation of monophasic compounds. The phase composition and purity confirmation of the samples were also characterized via FTIR spectroscopy. Desirable microstructural features and particle size of phosphorous materials of the polycrystalline samples were studied via scanning electron microscopy (SEM)...
January 18, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28098261/direct-observation-of-the-layer-by-layer-growth-of-zno-nanopillar-by-in-situ-high-resolution-transmission-electron-microscopy
#12
Xing Li, Shaobo Cheng, Shiqing Deng, Xianlong Wei, Jing Zhu, Qing Chen
Catalyst-free methods are important for the fabrication of pure nanowires (NWs). However, the growth mechanism remains elusive due to the lack of crucial information on the growth dynamics at atomic level. Here, the noncatalytic growth process of ZnO NWs is studied through in situ high resolution transmission electron microscopy. We observe the layer-by-layer growth of ZnO nanopillars along the polar [0001] direction under electron beam irradiation, while no growth is observed along the radial directions, indicating an anisotropic growth mechanism...
January 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28098229/novel-synthesis-of-zno-pmma-nanocomposites-for-photocatalytic-applications
#13
Alessandro Di Mauro, Maria Cantarella, Giuseppe Nicotra, Giovanna Pellegrino, Antonino Gulino, Maria Violetta Brundo, Vittorio Privitera, Giuliana Impellizzeri
The incorporation of nanostructured photocatalysts in polymers is a strategic way to obtain novel water purification systems. This approach takes the advantages of: (1) the presence of nanostructured photocatalyst; (2) the flexibility of polymer; (3) the immobilization of photocatalyst, that avoids the recovery of the nanoparticles after the water treatment. Here we present ZnO-polymer nanocomposites with high photocatalytic performance and stability. Poly (methyl methacrylate) (PMMA) powders were coated with a thin layer of ZnO (80 nm thick) by atomic layer deposition at low temperature (80 °C)...
January 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28098202/superresolution-imaging-of-clinical-formalin-fixed-paraffin-embedded-breast-cancer-with-single-molecule-localization-microscopy
#14
Matthew K Creech, Jing Wang, Xiaolin Nan, Summer L Gibbs
Millions of archived formalin-fixed, paraffin-embedded (FFPE) specimens contain valuable molecular insight into healthy and diseased states persevered in their native ultrastructure. To diagnose and treat diseases in tissue on the nanoscopic scale, pathology traditionally employs electron microscopy (EM), but this platform has significant limitations including cost and painstaking sample preparation. The invention of single molecule localization microscopy (SMLM) optically overcame the diffraction limit of light to resolve fluorescently labeled molecules on the nanoscale, leading to many exciting biological discoveries...
January 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28098140/dynamical-observations-on-the-crack-tip-zone-and-stress-corrosion-of-two-dimensional-mos2
#15
Thuc Hue Ly, Jiong Zhao, Magdalena Ola Cichocka, Lain-Jong Li, Young Hee Lee
Whether and how fracture mechanics needs to be modified for small length scales and in systems of reduced dimensionality remains an open debate. Here, employing in situ transmission electron microscopy, atomic structures and dislocation dynamics in the crack tip zone of a propagating crack in two-dimensional (2D) monolayer MoS2 membrane are observed, and atom-to-atom displacement mapping is obtained. The electron beam is used to initiate the crack; during in situ observation of crack propagation the electron beam effect is minimized...
January 18, 2017: Nature Communications
https://www.readbyqxmd.com/read/28097871/redox-responsive-self-assembly-micelles-from-poly-n-acryloylmorpholine-block-2-acryloyloxyethyl-ferrocene-carboxylate-amphiphilic-block-copolymers-as-drug-release-carriers
#16
Feng Xu, He Li, Yan-Ling Luo, Wei Tang
Novel well-defined redox-responsive ferrocene-containing amphiphilic block copolymers (PACMO-b-PAEFC) were synthesized by ATRP, with poly(N-acryloylmorpholine) (PACMO) as hydrophilic blocks and poly(2-acryloyloxyethyl ferrocenecarboxylate) (PAEFC) as hydrophobic blocks. The copolymers were characterized by FTIR, 1H NMR, and gel permeation chromatography, and the crystalline behavior was determined by X-ray diffraction and small-angle X-ray scattering. The results showed that the size of the lamellar crystals and crystallinity vary with the systematic compositions while the periodic structure of the lamellar stacks has no obvious change...
January 18, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28097666/understanding-external-cervical-resorption-patterns-in-endodontically-treated-teeth
#17
M Mavridou, E Hauben, M Wevers, E Schepers, L Bergmans, P Lambrechts
AIM: To understand the pattern of external cervical resorption (ECR) in endodontically treated teeth. To compare characteristics and mechanisms of ECR in root filled teeth with those established in teeth with vital pulps. METHODOLOGY: Seven cases of endodontically treated permanent teeth displaying ECR were investigated. ECR diagnosis was based on clinical findings and radiographic examination with cone-beam computed tomography (CBCT). The extracted teeth were further analysed by a nano-focus computed tomographic (nano-CT) system, hard tissue histology and scanning electron microscopy (SEM)...
January 18, 2017: International Endodontic Journal
https://www.readbyqxmd.com/read/28097598/influence-of-doping-and-nanostructuration-on-n-type-bi2-te0-8se0-2-3-alloys-synthesized-by-arc-melting
#18
Mouna Gharsallah, Federico Serrano-Sanchez, Norbert M Nemes, Jose Luis Martinez, Jose Antonio Alonso
In competitive thermoelectric devices for energy conversion and generation, high-efficiency materials of both n-type and p-type are required. For this, Bi2Te3-based alloys have the best thermoelectric properties in room temperature applications. Partial replacement of tellurium by selenium is expected to introduce new donor states in the band gap, which would alter electrical conductivity and thermopower. We report on the preparation of n-type Bi2(Te1-xSex)3 solid solutions by a straightforward arc-melting technique, yielding nanostructured polycrystalline pellets...
December 2017: Nanoscale Research Letters
https://www.readbyqxmd.com/read/28097596/enhancement-of-perovskite-solar-cells-efficiency-using-n-doped-tio2-nanorod-arrays-as-electron-transfer-layer
#19
Zhen-Long Zhang, Jun-Feng Li, Xiao-Li Wang, Jian-Qiang Qin, Wen-Jia Shi, Yue-Feng Liu, Hui-Ping Gao, Yan-Li Mao
In this paper, N-doped TiO2 (N-TiO2) nanorod arrays were synthesized with hydrothermal method, and perovskite solar cells were fabricated using them as electron transfer layer. The solar cell performance was optimized by changing the N doping contents. The power conversion efficiency of solar cells based on N-TiO2 with the N doping content of 1% (N/Ti, atomic ratio) has been achieved 11.1%, which was 14.7% higher than that of solar cells based on un-doped TiO2. To get an insight into the improvement, some investigations were performed...
December 2017: Nanoscale Research Letters
https://www.readbyqxmd.com/read/28097594/mechanism-of-anti-vibrio-activity-of-marine-probiotic-strain-bacillus-pumilus-h2-and-characterization-of-the-active-substance
#20
Xi-Yan Gao, Ying Liu, Li-Li Miao, Er-Wei Li, Ting-Ting Hou, Zhi-Pei Liu
Vibriosis is a major epizootic disease that impacts free-living and farmed fish species worldwide. Use of probiotics is a promising approach for prevention of Vibrio infections in aquaculture. A probiotic anti-Vibrio strain, Bacillus pumilus H2, was characterized, and the mechanism of its effect was investigated. All 29 Vibrio strains tested were growth-inhibited by H2. The anti-Vibrio substance present in cell-free supernatant of H2 was purified and characterized by reversed-phase HPLC. Minimum inhibitory concentrations of the purified substance, determined in liquid media for various Vibrio strains, ranged from 0...
December 2017: AMB Express
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