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https://www.readbyqxmd.com/read/28811019/introducing-a-new-and-rapid-microextraction-approach-based-on-magnetic-ionic-liquids-stir-bar-dispersive-liquid-microextraction
#1
Alberto Chisvert, Juan L Benedé, Jared L Anderson, Stephen A Pierson, Amparo Salvador
With the aim of contributing to the development and improvement of microextraction techniques, a novel approach combining the principles and advantages of stir bar sorptive extraction (SBSE) and dispersive liquid-liquid microextraction (DLLME) is presented. This new approach, termed stir bar dispersive liquid microextraction (SBDLME), involves the addition of a magnetic ionic liquid (MIL) and a neodymium-core magnetic stir bar into the sample allowing the MIL coat the stir bar due to physical forces (i.e., magnetism)...
August 29, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28809747/oxidation-of-pth-in-vivo-feature-or-effect-of-preanalytical-conditions
#2
Stan R Ursem, Marc G Vervloet, Jacquelien J G Hillebrand, Renate T de Jongh, Annemieke C Heijboer
BACKGROUND: Posttranslational oxidation of parathyroid hormone (PTH) modifies its biological activity. Measurement of non-oxidized PTH (n-oxPTH) could be an improvement in assessing PTH status, as intact PTH may rather reflect oxidative stress. However, it is debated whether oxidation of PTH occurs in vivo, or whether it is mainly an in vitro artifact. The aim of this study was to investigate the influence of different preanalytical conditions on the oxidation of PTH within a wide range of plasma PTH concentrations and oxidation propensity...
August 15, 2017: Clinical Chemistry and Laboratory Medicine: CCLM
https://www.readbyqxmd.com/read/28809049/evolution-of-mnc-and-lymphocyte-collection-settings-employing-different-spectra-optia-%C3%A2-leukapheresis-systems
#3
M Punzel, A Kozlova, A Quade, A H Schmidt, R Smith
BACKGROUND AND OBJECTIVES: The Spectra Optia(®) continuous mononuclear cell (CMNC apheresis) system has emerged as the preferred device in peripheral blood stem cell collections over the original two-step Spectra Optia(®) mononuclear cell (MNC apheresis) system. Until now, no comparative data were available for non-stimulated MNC collections that are required for immunotherapy. MATERIALS AND METHODS: We compared collection parameters and product composition for Spectra Optia MNC- as well as CMNC-apheresis systems in non-stimulated MNC collections from 35 registry donors intended for donor lymphocyte infusions...
August 14, 2017: Vox Sanguinis
https://www.readbyqxmd.com/read/28807092/extraction-and-determination-of-trace-amounts-of-p-coumaric-acid-in-vinegar-carrot-juice-and-seed-extract-from-silybum-marianum-l-gaertn
#4
Rouhollah Khani, Zeinab Rostami, Ghodsieh Bagherzade, Vahid Khojeh
In this study, for the monitoring and quantification of p-coumaric acid (p-CA) in vinegar, carrot juice, and seed extract from the plant species Silybum marianum (L.) Gaertn, an efficient and low-cost analytical method has been applied. For this purpose, a dispersive liquid-liquid microextraction (DLLME) method, followed by UV-Vis spectrophotometric detection, was used. To form a cloudy solution, a binary mixture containing ethanol as a disperser solvent and chloroform as an extraction solvent was rapidly injected by syringe into a sample solution containing p-CA...
August 10, 2017: Journal of AOAC International
https://www.readbyqxmd.com/read/28807034/exosomes-from-embryonic-mesenchymal-stem-cells-alleviate-osteoarthritis-through-balancing-synthesis-and-degradation-of-cartilage-extracellular-matrix
#5
Yafei Wang, Dongsheng Yu, Zhiming Liu, Fang Zhou, Jun Dai, Bingbing Wu, Jing Zhou, Boon Chin Heng, Xiao Hui Zou, Hongwei Ouyang, Hua Liu
BACKGROUND: Mesenchymal stem cell therapy for osteoarthritis (OA) has been widely investigated, but the mechanisms are still unclear. Exosomes that serve as carriers of genetic information have been implicated in many diseases and are known to participate in many physiological processes. Here, we investigate the therapeutic potential of exosomes from human embryonic stem cell-induced mesenchymal stem cells (ESC-MSCs) in alleviating osteoarthritis (OA). METHODS: Exosomes were harvested from conditioned culture media of ESC-MSCs by a sequential centrifugation process...
August 14, 2017: Stem Cell Research & Therapy
https://www.readbyqxmd.com/read/28805478/production-of-platelet-rich-plasma-gel-from-elderly-patients-under-antithrombotic-drugs-perspectives-in-chronic-wounds-care
#6
M Velier, J Magalon, A Daumas, M Cassar, P Francois, A Ghazouane, C Philandrianos, B Bertrand, C Frere, D Bernot, P Villani, F Dignat George, F Sabatier
Platelet-Rich Plasma (PRP) is an autologous biological therapy obtained by centrifuging the patient's own blood to concentrate platelets. The addition of autologous thrombin and calcium chloride to PRP allows the production of a semi-solid form called PRP gel. PRP gel is increasingly used in a variety of tissue defects and predominantly in the management of non-healing chronic wounds. The topical application of PRP gel seems promising due to the capability of platelets to store and secrete growth factors (GF), fibrin and cytokines, which are essentials for wound healing...
August 14, 2017: Platelets
https://www.readbyqxmd.com/read/28803962/post-analytical-stability-of-23-common-chemistry-and-immunochemistry-analytes-in-incurred-samples
#7
Betina Klint Nielsen, Tina Frederiksen, Lennart Friis-Hansen, Pia Bükmann Larsen
BACKGROUND: Storage of blood samples after centrifugation, decapping and initial sampling allows ordering of additional blood tests. The pre-analytic stability of biochemistry and immunochemistry analytes has been studied in detail, but little is known about the post-analytical stability in incurred samples. METHODS: We examined the stability of 23 routine analytes on the Dimension Vista® (Siemens Healthineers, Denmark): 42-60 routine samples in lithium-heparin gel tubes (Vacutainer, BD, USA) were centrifuged at 3000×g for 10min...
August 10, 2017: Clinical Biochemistry
https://www.readbyqxmd.com/read/28803542/spin-infection-enables-efficient-gene-delivery-to-muscle-stem-cells
#8
Yusaku Kodaka, Yoko Asakura, Atsushi Asakura
Viral vector-mediated foreign gene expression in cultured cells has been extensively used in stem cell studies to explore gene function. However, it is difficult to obtain high-quality stem cells and primary cells after viral vector infection. Here, we describe a new protocol for high-efficiency retroviral infection of primary muscle stem cell (satellite cell) cultures. We compared multiple commercially available transfection reagents to determine which was optimal for retroviral infections of primary myoblasts...
August 1, 2017: BioTechniques
https://www.readbyqxmd.com/read/28803541/ion-exchange-chromatography-purification-of-extracellular-vesicles
#9
Maja Kosanović, Bojana Milutinović, Sanja Goč, Ninoslav Mitić, Miroslava Janković
Despite numerous studies, isolating pure preparations of extracellular vesicles (EVs) has proven challenging. Here, we compared ion-exchange chromatography (IEC) to the widely used sucrose density gradient (SDG) centrifugation method for the purification of EVs. EVs in bulk were isolated from pooled normal human amniotic fluid (AF) by differential centrifugation followed by IEC or sucrose density gradient separation. The purity of the isolated EVs was evaluated by electrophoresis and lectin blotting/immuno blotting to monitor the distribution of total proteins, different EVs markers, and selected N-glycans...
August 1, 2017: BioTechniques
https://www.readbyqxmd.com/read/28802218/pharmaceutical-and-biomedical-applications-of-dispersive-liquid-liquid-microextraction
#10
REVIEW
Fotouh R Mansour, Mostafa A Khairy
Sample treatment is so crucial in pharmaceutical and biomedical analysis. Proper sample preparation protects the analytical instrument, increases the sensitivity, and enhances the selectivity by removing probable interfering substances. Dispersive liquid-liquid microextraction (DLLME) is one of the most important approaches in sample treatment. In normal DLLME, the organic droplet of the extractant is mixed with a dispersing solvent before being injected into the sample. After manual or mechanical shaking, the cloudy solution is centrifuged to break the formed emulsion...
August 1, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28801955/single-layer-centrifugation-of-fresh-dromedary-camel-semen-improves-sperm-quality-and-in-vitro-fertilization-capacity-compared-with-simple-sperm-washing
#11
C Malo, E G Crichton, J M Morrell, B S Pukazhenthi, J A Skidmore
Single layer centrifugation (SLC) through a colloid is a tool for selecting viable mammalian spermatozoa but has not been used previously for fresh dromedary camel sperm. Semen from six camels (2 ejaculates/male) was diluted 1:5 (v:v) or 1:10 (v:v) in a Tris-citrate-fructose buffer for mechanical liquefaction by gentle pipetting. Following liquefaction, semen was processed either by SLC or by centrifugation without a colloid (control). Total and progressive motilities, CASA kinematics, vitality and acrosome integrity (eosin-nigrosin) and plasma membrane integrity (Hypo-osmotic swelling test; HOST), and fertilizing ability in a heterologous assay (zona-free goat oocytes) were evaluated...
August 12, 2017: Reproduction in Domestic Animals, Zuchthygiene
https://www.readbyqxmd.com/read/28801072/irinotecan-chemotherapy-induced-intestinal-oxidative-stress-underlying-causes-of-disturbed-mucosal-water-and-electrolyte-transport
#12
Kaïs Rtibi, Slimen Selmi, Dhekra Grami, Hichem Sebai, Mohamed Amri, Lamjed Marzouki
Irinotecan, a chemotherapy drug, can cause acute diarrhea immediately after administration. Hence, the present study was designed to investigate the gastrointestinal (GI) disturbances after an intraperitoneal (IP) administration of irinotecan in rats.Twenty Wistar rats were separated into two groups of ten. Group A was considered as a control group (NaCl, 0.9%). Group B was treated with irinotecan at a single dose of 200mgkg(-1). The rats were observed for defecation. For the enteropooling test, the animals were sacrificed by decapitation 1h post-treatment...
July 23, 2017: Pathophysiology: the Official Journal of the International Society for Pathophysiology
https://www.readbyqxmd.com/read/28798936/antidiabetic-micro-nanoaggregates-from-ge-gen-qin-lian-tang-decoction-increase-absorption-of-baicalin-and-cellular-antioxidant-activity-in-vitro
#13
Dai Lin, Qian Du, Huiqin Wang, Guanzhen Gao, Jianwu Zhou, Lijing Ke, Tianbao Chen, Chris Shaw, Pingfan Rao
The antidiabetic effects of Ge-Gen-Qin-Lian-Tang decoction (GQD) have been proven clinically. In a pharmacological study conducted on STZ-induced diabetic rats, the constitutive aggregates/sediments of Ge-Gen-Qin-Lian-Tang decoction exhibited stronger hypoglycemic and antioxidant activities compared to the soluble compositions. This study aims to demonstrate the pharmacological properties of aggregates derived from GQD by measuring permeability of the active monomer phytochemicals (e.g., baicalin) in a Caco-2 cell monolayer and determine the cellular viability, intracellular redox status (MDA and SOD), and insulin secretion of pancreatic β-cell line, INS-1, following STZ-induced oxidative stress...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28798850/network-simulation-based-optimization-of-centrifugo-pneumatic-blood-plasma-separation
#14
S Zehnle, M Rombach, R Zengerle, F von Stetten, N Paust
Automated and robust separation of 14 μl of plasma from 40 μl of whole blood at a purity of 99.81% ± 0.11% within 43 s is demonstrated for the hematocrit range of 20%-60% in a centrifugal microfluidic polymer disk. At high rotational frequency, red blood cells (RBCs) within whole blood are concentrated in a radial outer RBC collection chamber. Simultaneously, plasma is concentrated in a radial inner pneumatic chamber, where a defined air volume is enclosed and compressed. Subsequent reduction of the rotational frequency to not lower than 25 Hz enables rapid transfer of supernatant plasma into a plasma collection chamber, with highly suppressed resuspension of red blood cells...
March 2017: Biomicrofluidics
https://www.readbyqxmd.com/read/28797664/investigation-of-zinc-oxide-particles-in-cosmetic-products-by-means-of-centrifugal-and-asymmetrical-flow-field-flow-fractionation
#15
Vanessa Sogne, Florian Meier, Thorsten Klein, Catia Contado
The dimensional characterization of insoluble, inorganic particles, such as zinc oxide ZnO, dispersed in cosmetic or pharmaceutical formulations, is of great interest considering the current need of declaring the possible presence of nanomaterials on the label of commercial products. This work compares the separation abilities of Centrifugal- and Asymmetrical Flow Field-Flow Fractionation techniques (CF3 and AF4, respectively), equipped with UV-vis, MALS and DLS detectors, in size sorting ZnO particles, both as pristine powders and after their extraction from cosmetic matrices...
August 1, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28796947/interplay-of-intermolecular-and-intramolecular-hydrogen-bonds-on-complex-formation-the-3-aminopropanol-water-van-der-waals-complex
#16
Andrew S Khalil, Anne-Marie Kelterer, Richard J Lavrich
This combined experimental and theoretical study answers the question whether the intramolecular hydrogen bond strength in amino alcohols is dependent on the ring size. For this purpose, the rotational spectrum of the 3-aminopropanol-H2O van der Waals complex was recorded using Fourier-transform microwave spectroscopy and fit to the rotational, quadrupole coupling, and centrifugal distortion constants of the Watson A-reduction Hamiltonian. The experimental results are consistent with an ab initio conformation calculated at the MP2/6-311++G(d,p) level that involves the lowest energy 3-aminopropanol monomer and consists of a hydrogen bonding network...
August 10, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28796944/effect-of-freezing-thermal-pasteurization-and-hydrostatic-pressure-on-fractionation-and-folate-recovery-in-egg-yolk
#17
Nassim Naderi, Yves Pouliot, James D House, Alain Doyen
In this study, the impact of pasteurization and freezing of raw material, as performed at a commercial scale, on egg yolk fractionation and folate recovery was assessed. Freezing induced denaturation of the lipoproteins in egg yolk which prevented further fractionation of the yolk. Thermal pasteurization of egg yolk at 61.1ºC for 3.5 min as well as high hydrostatic pressure (HHP) treatment (400 MPa for 5 min) did not change (p<0.05) the composition of egg yolk or yolk fractions after their recovery by centrifugation...
August 10, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28795656/development-and-validation-of-multi-residue-analysis-for-tetracycline-antibiotics-in-feed-by-high-performance-liquid-chromatography-coupled-to-mass-spectrometry
#18
Ewelina Patyra, Krzysztof Kwiatek
A new multi-residue method for the analysis of the tetracycline antibiotics oxytetracycline, tetracycline, chlortetracycline, and doxycycline was developed and validated for animal feed. After extraction with 0.1M Na2EDTA-McIlvaine buffer (pH 4), the samples were centrifuged, purified by SPE (Strata-X-CW cartridges) and analyzed by high-performance liquid chromatography coupled to mass spectrometry. Validation of the method was performed according to the guidelines indicated in Commission Decision 2002/657/EC...
August 10, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/28795250/metformin-reduces-total-microparticles-and-microparticles-expressing-tissue-factor-in-women-with-polycystic-ovary-syndrome
#19
Laura M L Carvalho, Cláudia N Ferreira, Ana L Candido, Fernando M Reis, Mirelle O Sóter, Mariana F Sales, Ieda F O Silva, Fernanda F C Nunes, Karina Braga Gomes
PURPOSE: The objective of this study was to evaluate the levels of total microparticles (MPs) and microparticles-expressing tissue factor (TFMPs) in women with polycystic ovarian syndrome (PCOS) who use metformin comparing to those who do not take metformin. METHODS: We quantified total MPs and TFMPs in the plasma of 50 patients with PCOS-13 of these women used metformin (850 mg 2×/day during at least 6 months) and the other 37 did not. For this purpose, the microparticles (MPs) were purified by differential centrifugation of the plasma and, subsequently, by flow cytometry, using annexin-V and CD142 as markers...
August 9, 2017: Archives of Gynecology and Obstetrics
https://www.readbyqxmd.com/read/28795163/a-reformulation-of-mechanics-and-electrodynamics
#20
Mario J Pinheiro
Classical mechanics, as commonly taught in engineering and science, are confined to the conventional Newtonian theory. But classical mechanics has not really changed in substance since Newton formulation, describing simultaneous rotation and translation of objects with somewhat complicate drawbacks, risking interpretation of forces in non-inertial frames. In this work we introduce a new variational principle for out-of-equilibrium, rotating systems, obtaining a set of two first order differential equations that introduces a thermodynamic-mechanistic time into Newton's dynamical equation, and revealing the same formal symplectic structure shared by classical mechanics, fluid mechanics and thermodynamics...
July 2017: Heliyon
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