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https://www.readbyqxmd.com/read/27933483/covalent-immobilization-of-human-placental-17%C3%AE-hydroxysteroid-dehydrogenase-type-1-onto-glutaraldehyde-activated-silica-coupled-with-lc-tof-ms-for-anti-cancer-drug-screening-applications
#1
Yin Bai, Wen-Di Zhou, Xian-Min Mu, Qian Zhang, Chen Yu, Bin Di, Meng-Xiang Su
Human 17β-hydroxysteroid dehydrogenase type 1 (17β-HSD1), a potential target in breast cancer prevention and therapy, was extracted from human placenta and immobilized on nonporous silica (∼5 μm) with a covalent method for the first time. The optimum initial enzyme concentration and immobilization time during the immobilization process were 0.42 mg mL(-1) and 12 h, repectively. The binding was confirmed by scanning electron microscope (SEM) and infrared spectroscopy (FT-IR). It could improve the pH, thermal and storage stability compared to free enzyme...
December 8, 2016: Applied Biochemistry and Biotechnology
https://www.readbyqxmd.com/read/27932538/investigation-of-solid-particles-in-the-mainstream-aerosol-of-the-tobacco-heating-system-ths2-2-and-mainstream-smoke-of-a-3r4f-reference-cigarette
#2
P Pratte, S Cosandey, C Goujon Ginglinger
Combustion of biomass produces solid carbon particles, whereas their generation is highly unlikely when a biomass is heated instead of being burnt. For instance, in the Tobacco Heating System (THS2.2), the tobacco is heated below 350°C and no combustion takes place. Consequently, at this relatively low temperature, released compounds should form an aerosol consisting of suspended liquid droplets via a homogeneous nucleation process. To verify this assumption, mainstream aerosol generated by the heat-not-burn product, THS2...
December 8, 2016: Human & Experimental Toxicology
https://www.readbyqxmd.com/read/27932259/a-comparative-study-for-lipase-immobilization-onto-alginate-based-composite-electrospun-nanofibers-with-effective-and-enhanced-stability
#3
Yasemin İspirli Doğaç, İlyas Deveci, Bedrettin Mercimek, Teke Mustafa
In this study, lipase was successfully immobilized on polyvinyl alcohol/alginate and polyethylene oxide/alginate nanofibers that were prepared by electrospinning. Results showed that nanofibers (especially polyvinyl alcohol/alginate) enhanced the stability properties of lipase. When the free lipase lost its all activity after 40-60min at high temperatures, both lipase immobilized nanofibers kept almost 65-70% activity at the same time. The lipase immobilized poly vinyl alcohol/alginate and polyethylene oxide/alginate nanofibers protected approximately all of their activities until pH 9...
December 5, 2016: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/27932203/neural-connection-supporting-endogenous-5-hydroxytryptamine-influence-on-autonomic-activity-in-medial-prefrontal-cortex
#4
Hao-Qiang Zhang, Yong Zhang, Lin Liu, Jin-Lian Li, Ya-Cheng Lu, Ying-Ying Yu, Hui Li, Ting Zhang, Ying-Shing Chan, Fu-Xing Zhang, Yun-Qing Li
5-hydroxytryptamine (5-HT) transmission in the medial prefrontal cortex (mPFC) enhances or suppresses signal outflow to influence emotion-/cognition-based function performances and, putatively, the autonomic responses. The top-down cortical modulation of autonomic activities may be mediated in part through projections from mPFC to brain stem dorsal vagal complex (DVC). The abundant and heterogeneous densities of 5-HT fibers across laminae in mPFC suggest serotonergic innervation of mPFC-DVC projection neurons whereby endogenous 5-HT acts to regulate autonomic activities...
December 1, 2016: Autonomic Neuroscience: Basic & Clinical
https://www.readbyqxmd.com/read/27931256/comparison-of-marginal-fit-of-cemented-zirconia-copings-manufactured-after-digital-impression-with-lava%C3%A2-c-o-s-and-conventional-impression-technique
#5
Rinet Dauti, Barbara Cvikl, Alexander Franz, Uwe Yacine Schwarze, Bledar Lilaj, Tina Rybaczek, Andreas Moritz
BACKGROUND: Evaluation of the marginal fit of cemented zirconia copings manufactured after digital impression with Lava™ Chairside Oral Scanner in comparison to that of zirconia copings manufactured after conventional impressions with polyvinyl siloxane. METHODS: A prepared typodont tooth #36, was replicated 40 times with a vinyl silicone and precise model resin. The dies were randomly divided into two groups according to the impression taking technique. Digital impressions with Lava™ C...
December 8, 2016: BMC Oral Health
https://www.readbyqxmd.com/read/27931218/scutellaria-barbata-flavonoids-alleviate-memory-deficits-and-neuronal-injuries-induced-by-composited-a%C3%AE-in-rats
#6
Xiao G Wu, Shu S Wang, Hong Miao, Jian J Cheng, Shu F Zhang, Ya Z Shang
BACKGROUND: The aim of the present study was to investigate the effects of Scutellaria barbata flavonoids (SBF) on memory impairment and neuronal injury induced by amyloid beta protein 25-35 in combination with aluminum trichloride (AlCl3) and recombinant human transforming growth factor-β1 (RHTGF-β1) (composited Aβ) in rats. METHODS: The composited Aβ-treated model of Alzheimer's disease (AD)-like memory impairment and neuronal injury was established in male rats by right intracerebroventricular injection of composited Aβ, and the effects of SBF were assessed using this rat model...
December 8, 2016: Behavioral and Brain Functions: BBF
https://www.readbyqxmd.com/read/27931125/morphology-and-age-related-changes-in-calcospherites-of-human-teeth-an-ultrastructural-study
#7
Jasbir Arora, Indu Talwar, Daisy Sahni, Vidya Rattan
BACKGROUND: Dentine has been examined extensively for age-related physiological changes but there exists limited data on age related changes at ultrastructural level of dentine Aim: The present study aimed to examine age related ultrastructural changes in calcospherites of human dentine under the scanning electron microscope. MATERIAL AND METHODS: 30 single rooted teeth of North Western adult Indians (18-75 yrs) were collected from the Department of Oral Health Sciences, PGIMER, Chandigarh...
December 8, 2016: Annals of Human Biology
https://www.readbyqxmd.com/read/27929115/tracking-the-coherent-generation-of-polaron-pairs-in-conjugated-polymers
#8
Antonietta De Sio, Filippo Troiani, Margherita Maiuri, Julien Réhault, Ephraim Sommer, James Lim, Susana F Huelga, Martin B Plenio, Carlo Andrea Rozzi, Giulio Cerullo, Elisa Molinari, Christoph Lienau
The optical excitation of organic semiconductors not only generates charge-neutral electron-hole pairs (excitons), but also charge-separated polaron pairs with high yield. The microscopic mechanisms underlying this charge separation have been debated for many years. Here we use ultrafast two-dimensional electronic spectroscopy to study the dynamics of polaron pair formation in a prototypical polymer thin film on a sub-20-fs time scale. We observe multi-period peak oscillations persisting for up to about 1 ps as distinct signatures of vibronic quantum coherence at room temperature...
December 8, 2016: Nature Communications
https://www.readbyqxmd.com/read/27929087/current-crowding-mediated-large-contact-noise-in-graphene-field-effect-transistors
#9
Paritosh Karnatak, T Phanindra Sai, Srijit Goswami, Subhamoy Ghatak, Sanjeev Kaushal, Arindam Ghosh
The impact of the intrinsic time-dependent fluctuations in the electrical resistance at the graphene-metal interface or the contact noise, on the performance of graphene field-effect transistors, can be as adverse as the contact resistance itself, but remains largely unexplored. Here we have investigated the contact noise in graphene field-effect transistors of varying device geometry and contact configuration, with carrier mobility ranging from 5,000 to 80,000 cm(2 )V(-1 )s(-1). Our phenomenological model for contact noise because of current crowding in purely two-dimensional conductors confirms that the contacts dominate the measured resistance noise in all graphene field-effect transistors in the two-probe or invasive four-probe configurations, and surprisingly, also in nearly noninvasive four-probe (Hall bar) configuration in the high-mobility devices...
December 8, 2016: Nature Communications
https://www.readbyqxmd.com/read/27928496/bioactive-mesoporous-wollastonite-particles-for-bone-tissue-engineering
#10
S Saravanan, Nagarajan Selvamurugan
The current investigation was aimed at identifying the role of mesoporous wollastonite particles on the healing of rat tibial bone defect. The bone defect was created with a 3-mm-diameter dental drill, and it was filled with mesoporous wollastonite particles. After second and fourth weeks of filling treatments, it was found that mesoporous wollastonite particles promoted bone formation as evidenced by X-ray, histological, scanning electron microscope, and energy-dispersive spectra studies. X-ray study showed the closure of drill hole as seen by high-dense radio-opacity image...
January 2016: Journal of Tissue Engineering
https://www.readbyqxmd.com/read/27928098/effect-of-bioglass-and-silica-coating-of-zirconia-substrate-on-its-bond-strength-to-resin-cement
#11
Maryam Moezzizadeh, Hanieh Nojedehian, Haleh Valizadeh Haghi
This study aimed to assess the effect of bioglass and silica coating of zirconia substrate on its bond strength to resin cement. A total of 120 specimens were used in this in-vitro, experimental study. Zirconia discs measuring 10×7×2 mm were cut from Y-TZP zirconia blocks, sintered, cleaned and received different surface treatments of sandblasting, bioglass powder coating+etching, bioglass powder coating+etching+silanization, bioglass slurry coating+etching, bioglass slurry coating+etching+silanization, silica coating+silanization, silica coating+etching+silanization and no treatment group (control)...
December 6, 2016: Dental Materials Journal
https://www.readbyqxmd.com/read/27927596/quantification-of-muscle-pathology-in-infantile-pompe-disease
#12
Anne Schänzer, Ann-Kathrin Kaiser, Christian Mühlfeld, Martin Kulessa, Werner Paulus, Harald von Plein, Marianne Rohrbach, Lara Viergutz, Eugen Mengel, Thorsten Marquardt, Bern Neubauer, Till Acker, Andreas Hahn
The effects of enzyme replacement therapy (ERT) in infantile Pompe disease are variable, necessitating the identification of biomarkers to assess the severity of disease and response to ERT. The aims of this study were to investigate whether quantification of muscle pathology in infantile Pompe disease prior to and during ERT is feasible at the light microscope, and to develop a score that summarizes the degree of muscle pathology in a comprehensive manner from PAS-stained resin sections alone. We, therefore, determined glycogen load, extent of muscle fibre disruption, and amount of autophagic vacuoles in resin-embedded muscle biopsy specimens from 11 infantile Pompe patients and 2 with early childhood phenotype by quantitative methods, correlated the findings with ultrastructural analyses, compared PAS-stained resin sections with conventional PAS-stained cryosections, and related the quantified degree of muscle damage from infantile patients to the effects of ERT...
November 3, 2016: Neuromuscular Disorders: NMD
https://www.readbyqxmd.com/read/27927092/an-rnai-screen-for-genes-involved-in-nanoscale-protrusion-formation-on-corneal-lens-in-drosophila-melanogaster
#13
Ryunosuke Minami, Chiaki Sato, Yumi Yamahama, Hideo Kubo, Takahiko Hariyama, Ken-Ichi Kimura
The "moth-eye" structure, which is observed on the surface of corneal lens in several insects, supports anti-reflective and self-cleaning functions due to nanoscale protrusions known as corneal nipples. Although the morphology and function of the "moth-eye" structure, are relatively well studied, the mechanism of protrusion formation from cell-secreted substances is unknown. In Drosophila melanogaster, a compound eye consists of approximately 800 facets, the surface of which is formed by the corneal lens with nanoscale protrusions...
December 2016: Zoological Science
https://www.readbyqxmd.com/read/27925336/non-exponential-growth-of-mycobacterium-leprae-thai-53-strain-cultured-in-vitro
#14
Kazunobu Amako, Ken-Ichiro Iida, Mitsumasa Saito, Yoshitosi Ogura, Tetsuya Hayashi, Shin-Ichi Yoshida
To determine why cultivation of Mycobacterium leprae in vitro has not been successful, we attempted to culture this bacterium in media supplemented with a variety of biological materials. We observed a slight increase in the number of cells in medium supplemented with human blood plasma and an extract of nude mouse tissue after more than 3 months of cultivation at 30°C. To ascertain whether this increase was real growth, we analyzed the growth by droplet digital PCR. The analysis had the following two results: the slow increase in the copy number of cell-associated DNA and the release of a large amount of DNA into the culture medium from bacterial cells during cultivation...
December 7, 2016: Microbiology and Immunology
https://www.readbyqxmd.com/read/27924812/interstitial-oxygen-as-a-source-of-p-type-conductivity-in-hexagonal-manganites
#15
Sandra H Skjærvø, Espen T Wefring, Silje K Nesdal, Nikolai H Gaukås, Gerhard H Olsen, Julia Glaum, Thomas Tybell, Sverre M Selbach
Hexagonal manganites, h-RMnO3 (R=Sc, Y, Ho-Lu), have been intensively studied for their multiferroic properties, magnetoelectric coupling, topological defects and electrically conducting domain walls. Although point defects strongly affect the conductivity of transition metal oxides, the defect chemistry of h-RMnO3 has received little attention. We use a combination of experiments and first principles electronic structure calculations to elucidate the effect of interstitial oxygen anions, Oi, on the electrical and structural properties of h-YMnO3...
December 7, 2016: Nature Communications
https://www.readbyqxmd.com/read/27924243/comparison-of-real-time-nanoparticle-monitoring-instruments-in-the-workplaces
#16
Seunghon Ham, Naroo Lee, Igchun Eom, Byoungcheun Lee, Perng-Jy Tsai, Kiyoung Lee, Chungsik Yoon
BACKGROUND: Relationships among portable scanning mobility particle sizer (P-SMPS), condensation particle counter (CPC), and surface area monitor (SAM), which are different metric measurement devices, were investigated, and two widely used research grade (RG)-SMPSs were compared to harmonize the measurement protocols. METHODS: Pearson correlation analysis was performed to compare the relation between P-SMPS, CPC, and SAM and two common RG-SMPS. RESULTS: For laboratory and engineered nanoparticle (ENP) workplaces, correlation among devices showed good relationships...
December 2016: Safety and Health At Work
https://www.readbyqxmd.com/read/27923513/on-the-influence-of-the-electron-dose-rate-on-the-hrtem-image-contrast
#17
Juri Barthel, Markus Lentzen, Andreas Thust
We investigate a possible dependence between the applied electron dose-rate and the magnitude of the resulting image contrast in HRTEM of inorganic crystalline objects. The present study is focussed on the question whether electron irradiation can induce excessively strong atom vibrations or displacements, which in turn could significantly reduce the resulting image contrast. For this purpose, high-resolution images of MgO, Ge, and Au samples were acquired with varying dose rates using a CS-corrected FEI Titan 80-300 microscope operated at 300kV accelerating voltage...
November 22, 2016: Ultramicroscopy
https://www.readbyqxmd.com/read/27920949/development-of-olfactory-epithelium-and-associated-structures-in-the-green-iguana-iguana-iguana-light-and-scanning-electron-microscopic-study
#18
Olga Sapoznikov, Petr Cizek, Frantisek Tichy
The ontogenesis of the nasal cavity has been described in many mammalian species. The situation is different with reptiles, despite the fact that they have become relatively common as pets. In this study we focused on the ontogenesis of the olfactory epithelium, as well as other types of epithelia in the nasal cavity of pre-hatched green iguanas (Iguana iguana). Collection of samples began from day 67 of incubation and continued every four days until hatching. Microscopic examination revealed that significant morphological changes in the nasal cavity began approximately at day 91 of ontogenesis...
2016: PeerJ
https://www.readbyqxmd.com/read/27920166/revealing-the-heterogeneous-contamination-process-in-metal-nanoparticulate-catalysts-in-co-gas-without-purification-by-in-situ-environmental-transmission-electron-microscopy
#19
Tetsuya Uchiyama, Hideto Yoshida, Naoto Kamiuchi, Hideo Kohno, Seiji Takeda
It is known that samples become contaminated in CO gas of high pressure unless care is taken with the gas supply line to an environmental transmission electron microscope. This technical note reveals the heterogeneous formation process of contamination in situ on a nanoparticulate catalyst sample. It is shown that the surface of metal nanoparticles is preferentially contaminated, while the surface of metal oxide supports remains uncontaminated. It is also demonstrated that the contamination is suppressed by introducing a gas purifier in a gas supply line...
December 2016: Microscopy
https://www.readbyqxmd.com/read/27919210/three-dimensional-modelling-of-the-voltage-gated-sodium-ion-channel-from-anopheles-gambiae-reveals-spatial-clustering-of-evolutionarily-conserved-acidic-residues-at-the-extracellular-sites
#20
Rithvik S Vinekar, Ramanathan Sowdhamini
The eukaryotic voltage-gated sodium channel(e-Nav) is a large asymmetric transmembrane protein with important functions concerning neurological function. No structure has been resolved at high resolution for this protein. A homology model of the transmembrane and extracellular regions of an Anopheles gambiae para-like channel with emphasis on the pore entrance has been constructed, based upon the templates provided by a prokaryotic sodium channel and a potassium two-pore channel. The latter provides a template for the extracellular regions, which are located above the entrance to the pore, which is likely to open at a side of a dome formed by these loops...
December 5, 2016: Current Neuropharmacology
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