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https://www.readbyqxmd.com/read/28346432/nanoscale-capillary-freezing-of-ionic-liquids-confined-between-metallic-interfaces-and-the-role-of-electronic-screening
#1
Jean Comtet, Antoine Niguès, Vojtech Kaiser, Benoit Coasne, Lydéric Bocquet, Alessandro Siria
Room-temperature ionic liquids (RTILs) are new materials with fundamental importance for energy storage and active lubrication. They are unusual liquids, which challenge the classical frameworks of electrolytes, whose behaviour at electrified interfaces remains elusive, with exotic responses relevant to their electrochemical activity. Using tuning-fork-based atomic force microscope nanorheological measurements, we explore here the properties of confined RTILs, unveiling a dramatic change of the RTIL towards a solid-like phase below a threshold thickness, pointing to capillary freezing in confinement...
March 27, 2017: Nature Materials
https://www.readbyqxmd.com/read/28345866/biocompatible-hydroxylated-boron-nitride-nanosheets-polyvinyl-alcohol-interpenetrating-hydrogels-with-enhanced-mechanical-and-thermal-responses
#2
Lin Jing, Hongling Li, Roland Yingjie Tay, Bo Sun, Siu Hon Tsang, Olivier Cometto, Jinjun Lin, Edwin Hang Tong Teo, Alfred Iing Yoong Tok
Polyvinyl alcohol (PVA) hydrogels with tissue-like viscoelasticity, excellent biocompatibility and high hydrophilicity have been considered as promising cartilage replacement materials. However, lack of sufficient mechanical properties is a critical barrier to their usage as load-bearing cartilage substitutes. Herein, we report hydroxylated boron nitride nanosheets (OH-BNNS)/PVA interpenetrating hydrogels by cyclically freezing/thawing the aqueous mixture of PVA and highly hydrophilic OH-BNNS (up to 0.6 mg/mL, two times the highest reported so far)...
March 27, 2017: ACS Nano
https://www.readbyqxmd.com/read/28344636/development-of-an-efficient-glucosinolate-extraction-method
#3
T Doheny-Adams, K Redeker, V Kittipol, I Bancroft, S E Hartley
BACKGROUND: Glucosinolates, anionic sulfur rich secondary metabolites, have been extensively studied because of their occurrence in the agriculturally important brassicaceae and their impact on human and animal health. There is also increasing interest in the biofumigant properties of toxic glucosinolate hydrolysis products as a method to control agricultural pests. Evaluating biofumigation potential requires rapid and accurate quantification of glucosinolates, but current commonly used methods of extraction prior to analysis involve a number of time consuming and hazardous steps; this study aimed to develop an improved method for glucosinolate extraction...
2017: Plant Methods
https://www.readbyqxmd.com/read/28344398/evaluation-of-tissue-engineered-bone-constructs-using-rabbit-fetal-osteoblasts-on-acellular-bovine-cancellous-bone-matrix
#4
Rashmi, Rekha Pathak, Amarpal, H P Aithal, P Kinjavdekar, A M Pawde, A K Tiwari, P Sangeetha, P Tamilmahan, A B Manzoor
AIM: The aim of this study was to generate composite bone graft and investigate the rabbit fetal osteoblasts adhesion, proliferation and penetration on acellular matrices of cancellous bone. MATERIALS AND METHODS: Acellular cancellous bone was prepared and developed as in the previous study with little modification. These matrices were decellularized by rapid freeze and thaw cycle. To remove the cell debris, they were then treated with hydrogen peroxide (3%) and ethanol to remove antigenic cellular and nuclear materials from the scaffold...
February 2017: Veterinary World
https://www.readbyqxmd.com/read/28344202/three-year-clinical-outcome-after-2nd-generation-cryoballoon-based-pulmonary-vein-isolation-for-the-treatment-of-paroxysmal-and-persistent-atrial-fibrillation%C3%A3-a-2-center-experience
#5
Christian-H Heeger, Erik Wissner, Milena Knöll, Benedikt Knoop, Bruno Reissmann, Shibu Mathew, Christian Sohns, Christine Lemes, Tilman Maurer, Francesco Santoro, Johannes Riedl, Osamu Inaba, Thomas Fink, Laura Rottner, Peter Wohlmuth, Britta Goldmann, Feifan Ouyang, Karl-Heinz Kuck, Andreas Metzner
BACKGROUND: Pulmonary vein isolation (PVI) using the 2nd-generation cryoballoon (CB2) for the treatment of atrial fibrillation (AF) has demonstrated encouraging acute and mid-term results. However, follow-up data on outcomes beyond 1 year are sparse. We investigated the 3-year outcome after PVI using the CB2.Methods and Results:100 patients with paroxysmal (PAF, 70/100 [70%] patients) or persistent AF (pAF, 30/100 [30%] patients) underwent CB2-based PVI in 2 experienced centers in Germany...
March 24, 2017: Circulation Journal: Official Journal of the Japanese Circulation Society
https://www.readbyqxmd.com/read/28344085/protection-of-polyphenols-in-blueberry-juice-by-vacuum-assisted-block-freeze-concentration
#6
Patricio Orellana-Palma, Guillermo Petzold, Lissage Pierre, José Manuel Pensaben
Block freeze concentration allows produces high-quality cryoconcentrates with important protection of valuable components from fresh fruit juices. The aim of this study was to investigate the use of vacuum-assisted block freeze concentration under different experimental conditions to protect polyphenols in the elaboration of concentrated blueberry juice. Fresh blueberry juice was radial or unidirectional frozen at -20 and -80 °C for 12 h and vacuum process was performed at 80 kPa during 120 min. Results showed a significant solute increased in the concentrated fraction in all treatments, and the best treatment was - 20 °C/unidirectional with a value of ≈63 °Brix, equivalent to an increase of 3...
March 23, 2017: Food and Chemical Toxicology
https://www.readbyqxmd.com/read/28344081/plasma-membrane-crpk1-mediated-phosphorylation-of-14-3-3-proteins-induces-their-nuclear-import-to-fine-tune-cbf-signaling-during-cold-response
#7
Ziyan Liu, Yuxin Jia, Yanglin Ding, Yiting Shi, Zhen Li, Yan Guo, Zhizhong Gong, Shuhua Yang
In plant cells, changes in fluidity of the plasma membrane may serve as the primary sensor of cold stress; however, the precise mechanism and how the cell transduces and fine-tunes cold signals remain elusive. Here we show that the cold-activated plasma membrane protein cold-responsive protein kinase 1 (CRPK1) phosphorylates 14-3-3 proteins. The phosphorylated 14-3-3 proteins shuttle from the cytosol to the nucleus, where they interact with and destabilize the key cold-responsive C-repeat-binding factor (CBF) proteins...
March 21, 2017: Molecular Cell
https://www.readbyqxmd.com/read/28344002/establishment-of-a-human-blood-brain-barrier-co-culture-model-mimicking-the-neurovascular-unit-using-induced-pluri-and-multipotent-stem-cells
#8
Antje Appelt-Menzel, Alevtina Cubukova, Katharina Günther, Frank Edenhofer, Jörg Piontek, Gerd Krause, Tanja Stüber, Heike Walles, Winfried Neuhaus, Marco Metzger
In vitro models of the human blood-brain barrier (BBB) are highly desirable for drug development. This study aims to analyze a set of ten different BBB culture models based on primary cells, human induced pluripotent stem cells (hiPSCs), and multipotent fetal neural stem cells (fNSCs). We systematically investigated the impact of astrocytes, pericytes, and NSCs on hiPSC-derived BBB endothelial cell function and gene expression. The quadruple culture models, based on these four cell types, achieved BBB characteristics including transendothelial electrical resistance (TEER) up to 2,500 Ω cm(2) and distinct upregulation of typical BBB genes...
March 22, 2017: Stem Cell Reports
https://www.readbyqxmd.com/read/28343990/impact-of-freeze-thaw-process-on-drug-substance-storage-of-therapeutics
#9
William J Rayfield, Sunitha Kandula, Heera Khan, Nihal Tugcu
The storage of drug substance at subzero temperatures mitigates potential risks associated with liquid storage, such as degradation and shipping stress, making it the best solution for long term storage. However, slower (generally uncontrolled) rates of freezing and thawing of drug substance in conventional large storage containers (> 2L) can lead to greater cryoconcentration (exclusion of solute molecules) resulting in zones of higher protein and excipient concentrations and changes to the desired formulation pH and excipient concentration...
March 23, 2017: Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28343042/in-situ-determination-of-trace-elements-in-fucus-spp-by-field-portable-xrf
#10
Andrew Turner, Hiu Poon, Alex Taylor, Murray T Brown
Fresh and freeze-dried sample sections of the coastal macroalgae, Fucus serratus and F. vesiculosus, and the brackish water macroalga, F. ceranoides, have been analysed for trace elements by field-portable-X-ray fluorescence (FP-XRF) spectrometry using a Niton XL3t in a low density mode with thickness correction. When analysed fresh in a laboratory accessory stand for a period of 200 seconds, As, Br, Fe and Zn were registered in the apex, mid-frond and lower stipe of all species, with detection limits of a few μg g(-1) (As) or a few tens of μg g(-1) (Br, Fe, Zn); when analysed dry under the same conditions, concentrations returned were systematically higher and Cu and Pb were detected in a number of F...
March 23, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28342406/phase-change-heat-transfer-during-cryosurgery-of-lung-cancer-using-hyperbolic-heat-conduction-model
#11
Ajay Kumar, Sushil Kumar, V K Katiyar, Shirley Telles
The paper reports a numerical study of phase change heat transfer process in lung cancer undergoing cryosurgery. A two dimensional hyperbolic bio-heat model with non-ideal property of tissue, blood perfusion and metabolism is used to analyze the problem. The governing equations are solved by finite difference method based on enthalpy formulation. Effects of relaxation time of heat flux in hyperbolic model on freezing process have been examined. A comparative investigation of two different models (hyperbolic and parabolic bio-heat models) is also presented...
March 16, 2017: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/28342099/optimized-decellularization-protocol-including-%C3%AE-gal-epitope-reduction-for-fabrication-of-an-acellular-porcine-annulus-fibrosus-scaffold
#12
Lien-Chen Wu, Yi-Jie Kuo, Fu-Wen Sun, Chia-Hsien Chen, Chang-Jung Chiang, Pei-Wei Weng, Yang-Hwei Tsuang, Yi-You Huang
Recent advances in tissue engineering have led to potential new strategies, especially decellularization protocols from natural tissues, for the repair, replacement, and regeneration of intervertebral discs. This study aimed to validate our previously reported method for the decellularization of annulus fibrosus (AF) tissue and to quantify potentially antigenic α-Gal epitopes in the decellularized tissue. Porcine AF tissue was decellularized using different freeze-thaw temperatures, chemical detergents, and incubation times in order to determine the optimal method for cell removal...
March 24, 2017: Cell and Tissue Banking
https://www.readbyqxmd.com/read/28341935/a-natural-triterpenoid-saponin-as-multifunctional-stabilizer-for-drug-nanosuspension-powder
#13
Yingchong Chen, Yang Liu, Junnan Xu, Yuanbiao Xie, Qin Zheng, Pengfei Yue, Ming Yang
The objective of this study is to prepare a novel drug nanosuspension modified by a natural triterpenoid saponin (glycyrrhizin (GZ)) and evaluate its stability and redispersibility. A poorly soluble drug (andrographolide (AGE)) was used as a model drug. AGE nanosuspensions (AGE-NS) using GZ as natural stabilizer with mean particle size of 487 nm were firstly prepared by homogenization and converted into dried AGE nanosuspension powder (AGE-NP) by freeze-drying. It was found that GZ was able to prevent the aggregation of AGE nanocrystals and the freeze-dried AGE-NP could easily redisperse back to AGE-NS...
March 24, 2017: AAPS PharmSciTech
https://www.readbyqxmd.com/read/28341787/potential-new-treatment-for-non-freezing-cold-injury-is-iloprost-the-way-forward
#14
Anne-Marie Ionescu, Sarah Hutchinson, Mehtab Ahmad, Christopher Imray
INTRODUCTION: Non-freezing cold injury (NFCI) remains largely under-reported, and is of particular importance in the armed forces where its prevalence is greatest. Iloprost, a synthetic prostaglandin I2 analogue, has previously been used with some success in the treatment of vasospastic and freezing cold injuries, although its role in NFCI remains unclear. CASE REPORT: An Iloprost infusion was used to treat the long-term sequelae of an ex-soldier suffering with ongoing pedal pain and loss of function 20 years after the initial NFCI insult sustained on military exercise...
March 23, 2017: Journal of the Royal Army Medical Corps
https://www.readbyqxmd.com/read/28341611/extinction-memory-is-facilitated-by-methylphenidate-and-regulated-by-dopamine-and-noradrenaline-receptors
#15
Cristiane R G Furini, Jonny A K Behling, Carolina G Zinn, Mara Lize Zanini, Eduardo S Assis Brasil, Luiza Doro Pereira, Ivan Izquierdo, Jociane de C Myskiw
Extinction is defined as the learned inhibition of retrieval and is the mainstay of exposure therapy, which is widely used to treat drug addiction, phobias and fear disorders. The psychostimulant, methylphenidate (MPH) is known to increase extracellular levels of noradrenaline and dopamine by blocking their reuptake and studies have demonstrated that MPH can modulate hippocampal physiology and/or functions including long-term potentiation (LTP), learning and memory. However, the influence of MPH on fear extinction memory has been insufficiently studied...
March 21, 2017: Behavioural Brain Research
https://www.readbyqxmd.com/read/28341598/lyophilized-drug-product-cake-appearance-what-is-acceptable
#16
Sajal Manubhai Patel, Steven L Nail, Michael J Pikal, Raimund Geidobler, Gerhard Winter, Andrea Hawe, Juan Davagnino, Shailaja Rambhatla Gupta
Cake appearance is an important attribute of freeze-dried products, which may or may not be critical with respect to product quality (i.e., safety and efficacy). Striving for "uniform and elegant" cake appearance may continue to remain an important goal during the design and development of a lyophilized drug product. However, sometimes a non-ideal cake appearance has no impact on product quality and is an inherent characteristic of the product (either due to formulation, drug product presentation and/or freeze-drying process)...
March 21, 2017: Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28341432/development-validation-and-evaluation-of-an-analytical-method-for-the-determination-of-monomeric-and-oligomeric-procyanidins-in-apple-extracts
#17
Wendy J Hollands, Stefan Voorspoels, Griet Jacobs, Kjersti Aaby, Ane Meisland, Rocio Garcia-Villalba, Francisco Tomas-Barberan, Mariusz K Piskula, Deborah Mawson, Irena Vovk, Paul W Needs, Paul A Kroon
There is a lack of data for individual oligomeric procyanidins in apples and apple extracts. Our aim was to develop, validate and evaluate an analytical method for the separation, identification and quantification of monomeric and oligomeric flavanols in apple extracts. To achieve this, we prepared two types of flavanol extracts from freeze-dried apples; one was an epicatechin-rich extract containing ∼30% (w/w) monomeric (-)-epicatechin which also contained oligomeric procyanidins (Extract A), the second was an oligomeric procyanidin-rich extract depleted of epicatechin (Extract B)...
March 18, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28341417/poor-knowledge-of-age-related-fertility-decline-and-assisted-reproduction-among-healthcare-professionals
#18
Désirée García, Rita Vassena, Andrés Prat, Valérie Vernaeve
Reproduction is a matter of concern for individuals and society due to the postponement of childbearing, and healthcare professionals are the main source of information and counselling. This study aims to evaluate how knowledgeable healthcare professionals are about fertility and assisted reproduction, and to explore attitudes towards social oocyte freezing. A cross-sectional study was performed with 201 professionals (gynaecologists, physicians and nurses) from four public centres in Spain. Participants completed a survey about fertility, IVF, oocyte donation (OD) and social oocyte freezing, between May 2013 and March 2014...
January 2017: Reproductive Biomedicine Online
https://www.readbyqxmd.com/read/28341230/intraoperative-cryoanalgesia-for-managing-pain-after-the-nuss-procedure
#19
Claire Graves, Olajire Idowu, Sang Lee, Benjamin Padilla, Sunghoon Kim
BACKGROUND: Cryoanalgesia prevents pain by freezing the affected peripheral nerve. We report the use of intraoperative cryoanalgesia during the Nuss procedure for pectus excavatum and describe our initial experience, modifications of technique, and lessons learned. MATERIALS AND METHODS: We retrospectively reviewed the medical records of patients who received cryoanalgesia during the Nuss procedure between June 1, 2015, and April 30, 2016, at our institutions and analyzed modifications in surgical technique during this early adoption period...
March 16, 2017: Journal of Pediatric Surgery
https://www.readbyqxmd.com/read/28341133/sperm-cryopreservation-in-the-spermcasting-australian-flat-oyster-ostrea-angasi-by-a-programmable-freezing-method
#20
Md Mahbubul Hassan, Xiaoxu Li, Yibing Liu, Jian G Qin
Cryopreservation offers long-term storage of gametes without constraint from seasonal gamete maturation, provides opportunities to improve the efficiency of breeding and genetic programs, and protects endangered species from extinction due to epidemic diseases and natural disasters. In this study, a protocol for cryopreserving sperm of the spermcasting Australian flat oyster Ostrea angasi was developed by optimizing key factors influencing the quality of cryopreserved sperm. Dimethyl sulfoxide (DMSO) was non-toxic to sperm within the concentration and duration assessed in the toxicity experiment whereas 10% methanol or a higher concentration was toxic to sperm from the exposure duration of 30 min onwards...
March 21, 2017: Cryobiology
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