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Ultra High Dilution

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https://www.readbyqxmd.com/read/30296508/substitution-therapy-with-amphetamine-isotherapic-attenuates-amphetamine-toxicological-aspects-of-addiction
#1
Hecson J Segat, Vinícia G Metz, Higor Z Rosa, Verônica T Dias, Raquel C S Barcelos, Geisa S Dolci, Marilise E Burger
INTRODUCTION: amphetamine (AMPH) is related to development of addiction, anxiety-like behaviors and impairments of memory after chronic use. In the current experiment, an ultra-high dilution (10-24 mg/mL) of AMPH was used, consisting of the AMPH isotherapic (AMPH-ISO), which can be used as a replacement therapy to treat AMPH addiction. AIM: To verify the influence of AMPH-ISO on toxicological aspects of AMPH addiction. METHODS: Rats received d,l-AMPH (4...
October 5, 2018: Neuroscience Letters
https://www.readbyqxmd.com/read/30293592/a-stable-method-for-routine-analysis-of-oxylipins-from-dried-blood-spots-using-ultra-high-performance-liquid-chromatography-tandem-mass-spectrometry
#2
Erandi Hewawasam, Ge Liu, David W Jeffery, Beverly S Muhlhausler, Robert A Gibson
Oxylipins are biologically important lipid mediators that are derived enzymatically from polyunsaturated fatty acids (PUFA) and have a major role in regulating inflammatory processes. The currently available methods for measuring oxylipins from human biological samples have limitations, which restricts their use in large studies. We have developed a novel method for measuring 21 oxylipins from dried blood spot (DBS) using ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and stable isotope dilution analysis...
October 2018: Prostaglandins, Leukotrienes, and Essential Fatty Acids
https://www.readbyqxmd.com/read/30290377/biological-actions-electrical-conductance-and-silicon-containing-microparticles-of-arsenicum-album-prepared-in-plastic-and-glass-vials
#3
Luciane Costa Dalboni, Cideli de Paula Coelho, Renata Rossettini Palombo Pedro, Michelle Sanchez Correia, Fabiana Rodrigues de Santana, Thayná Neves Cardoso, Sandra Augusta G Pinto, Anuska M Alvares-Saraiva, Maristela Dutra-Correa, Giovani B Peres, Carla Holandino, André Rossi, Amarilys de Toledo César, Silvia Waisse, Leoni Villano Bonamin
INTRODUCTION:  According to the "silica hypothesis" formulated to explain homeopathy, the information of starting materials would be transferred to cells by silica nanoparticles detached from the glassware walls by serial dilution and agitation through epitaxy. We compared the biological activity, electrical current and silicon microparticle content (by means of scanning electron microscopy/energy-dispersive X-ray spectroscopy) of high dilutions (HDs) of arsenic prepared in plastic and glass vials to investigate the role of silica in their biological effects in vitro...
October 5, 2018: Homeopathy: the Journal of the Faculty of Homeopathy
https://www.readbyqxmd.com/read/30290116/ionic-strength-effects-on-the-reactive-uptake-of-ozone-on-aqueous-pyruvic-acid-implications-for-air-sea-ozone-deposition
#4
Majda Mekic, Gwendal Loisel, Wentao Zhou, Bin Jiang, Davide Vione, Sasho Gligorovski
A vertical wetted-wall flow-tube technique was used to explore the ionic strength effects at the air-water interface in mediating the sea-surface reaction between ozone (O3 ) and pyruvic acid (PA). The uptake coefficients of ozone on aqueous PA increase substantially with the concentrations of bromide (Br- ) ions, clearly indicating that the dry deposition of ozone could be significantly enhanced due to the presence of carbonyl compounds such as PA at the bromide-rich sea surface. Based on the observed uptake coefficients, the estimated deposition velocity of ozone (100 ppb) for a nanomolar range of PA concentrations is ∼1 × 10-3 m s-1 , which represents a significant contribution to the known deposition velocity of ozone at the sea surface...
October 17, 2018: Environmental Science & Technology
https://www.readbyqxmd.com/read/30278760/a-scanning-tunneling-microscope-for-spectroscopic-imaging-below-90-mk-in-magnetic-fields-up-to-17-5-t
#5
T Machida, Y Kohsaka, T Hanaguri
We describe the development and performance of an ultra-high vacuum scanning tunneling microscope working under combined extreme conditions of ultra-low temperatures and high magnetic fields. We combined a top-loading dilution refrigerator and a standard bucket dewar with a bottom-loading superconducting magnet to achieve 4.5 days operating time, which is long enough to perform various spectroscopic-imaging measurements. To bring the effective electron temperature closer to the mixing-chamber temperature, we paid particular attention to filtering out radio-frequency noise, as well as enhancing the thermal link between the microscope unit and the mixing chamber...
September 2018: Review of Scientific Instruments
https://www.readbyqxmd.com/read/30278323/a-multidimensional-analytical-approach-based-on-time-decoupled-online-comprehensive-two-dimensional-liquid-chromatography-coupled-with-ion-mobility-quadrupole-time-of-flight-mass-spectrometry-for-the-analysis-of-ginsenosides-from-white-and-red-ginsengs
#6
Hong Zhang, Jia-Ming Jiang, Dan Zheng, Ming Yuan, Zhi-Ying Wang, Hong-Mei Zhang, Chang-Wu Zheng, Lian-Bo Xiao, Hong-Xi Xu
Here, time-decoupled comprehensive two-dimensional ultra-high liquid chromatography (UHPLC) coupled with an ion mobility (IM)-high resolution mass spectrometer (HRMS) was established and used to analyze ginsenosides from the main roots of white ginseng (WG) and red ginseng (RG), which enabled the separation of complex samples in four dimensions (2D-LC, ion mobility, and mass spectrometry). The incompatibility of mobile phases, dilution effect, and long analysis time, which are the main shortcomings of traditional comprehensive 2D-LC methods, were largely avoided in this newly established 2D-UHPLC method...
September 21, 2018: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/30262078/bromine-and-iodine-determination-in-human-saliva-challenges-in-the-development-of-an-accurate-method
#7
Diogo La Rosa Novo, Julia Eisenhardt Mello, Filipe Soares Rondan, Alessandra Schneider Henn, Paola Azevedo Mello, Marcia Foster Mesko
In this work, an analytical method for bromine and iodine determination in human saliva was proposed. A simple protocol based on centrifugation and direct analysis of supernatant by inductively coupled plasma mass spectrometry (ICP-MS) was investigated. Although this method was feasible for bromine determination, iodine was partially present in the supernatant and an agreement about 54% with reference value was obtained. In addition, microwave-induced combustion (MIC) and microwave-assisted dissolution were also evaluated...
January 1, 2019: Talanta
https://www.readbyqxmd.com/read/30238479/development-and-validation-of-a-hydrophilic-interaction-ultra-high-performance-liquid-chromatography-tandem-mass-spectrometry-method-for-rapid-simultaneous-determination-of-19-free-amino-acids-in-rat-plasma-and-urine
#8
Yongqing Wen, Xuemei Yuan, Feng Qin, Longshan Zhao, Zhili Xiong
Determination of amino acids in biofluids was a challenging task because of difficulties derived from their high polarity and matrix interference. A simple, reliable and high-throughput hydrophilic interaction UHPLC-MS/MS method was developed and validated for the rapid simultaneous determination of 19 free amino acids in rat plasma and urine samples in this paper. Hydrophilic method with Waters ACQUITY UPLC BEH Amide column(100×2.1mm,1.7μm) was used with a gradient mobile phase system of acetonitrile and water both containing 0...
September 20, 2018: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/30224277/high-throughput-gas-chromatography-mass-spectrometry-analysis-of-pesticide-residues-in-spices-by-using-the-enhanced-matrix-removal-lipid-and-the-sample-dilution-approach
#9
E Hakme, A Lozano, S Uclés, M M Gómez-Ramos, A R Fernández-Alba
Spices are known as difficult matrices that contain variable amounts of fats, piperine or many other matrix constituents. The increasing sensitivity of new GC-MS/MS platforms opens new approaches to analyze pesticide residue in complex matrices such as spices, by sample dilution. The aim of this work is to develop and validate an effective multiresidue method for the analysis of pesticide residues in spices by GC-MS/MS. In this paper, we highlight the importance of reducing matrix interferences generated from co-extractive components of spices...
October 26, 2018: Journal of Chromatography. A
https://www.readbyqxmd.com/read/30211858/amplified-measurement-of-weak-optical-activity-using-a-spin-phase-gradient-beam
#10
Rashmi Ranjan Suna, Nirmal K Viswanathan
Development of alternate techniques to polarimetry for the measurement of weak optical rotation, with improved sensitivity, is becoming increasingly important as one understands the role of chirality in drug design and synthesis and the fundamentals of chiral light-matter interaction. We demonstrate here an optical amplification scheme using a spin-phase-gradient beam to measure ultra-small optical rotation angle (4 mdeg), with a sensitivity of 220 μdeg/μm, due to dilute (mg/mL) dextro-rotatory sugar solution...
September 15, 2018: Optics Letters
https://www.readbyqxmd.com/read/30136534/-determination-of-fipronil-and-its-metabolites-in-feeds-by-stable-isotope-dilution-ultra-high-performance-liquid-chromatography-tandem-mass-spectrometry
#11
Peng Zhou, Qian Huang, Liqun Ouyang, Zheng Wang, Peng Meng, Ming Dai, Ying Wang
A method based on ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was established for the determination of fipronil and its metabolites in feeds. Sodium chloride was added to the samples after the ultrasonic extraction of pure water and acetonitrile, and then cleaned up by the QuEChERS method. The target analytes were separated on a Waters HSS T3 C18 column using methanol and water as mobile phases with gradient elution, and detected by a MS/MS system under negative electro-spry ionization (ESI- ) and the multiple reaction monitoring (MRM) mode...
July 8, 2018: Se Pu, Chinese Journal of Chromatography
https://www.readbyqxmd.com/read/30119142/development-and-validation-of-a-uplc-ms-ms-method-for-quantification-of-osimertinib-azd9291-and-its-metabolite-az5104-in-human-plasma
#12
Xin Zheng, Weicong Wang, Yanbao Zhang, Yuxiang Ma, Hongyun Zhao, Pei Hu, Ji Jiang
Osimertinib (AZD9291) is a highly selective irreversible epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI) designed to treat nonsmall-cell lung cancer patients with EGFR active and T790 M resistant mutations. A rapid and sensitive method for quantitative analysis by ultra-performance liquid chromatography-tandem mass spectrometry of osimertinib and its metabolite AZ5104 in human plasma was developed and validated. The samples were prepared by protein precipitation and separated on a BEH C18 column (2...
August 17, 2018: Biomedical Chromatography: BMC
https://www.readbyqxmd.com/read/30086920/determination-of-ultra-trace-sulfur-in-high-purity-metals-by-isotope-dilution-inductively-coupled-plasma-sector-field-mass-spectrometry-combined-with-chemical-separation-procedure
#13
Ayaka Wada, Naoko Nonose, Masaki Ohata, Tsutomu Miura
The analytical method of ultra-trace sulfur (S) in high-purity metal by isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS) combined with chemical separation procedure was developed in the present study. In order to determine the ultra-trace S in high-purity metal, a chemical separation with alumina column was carried out before ICP-MS measurement. This method enabled to prevent the polyatomic ion interference arising from the metal matrix and the signal suppression derived from the space charge effect in ICP-MS...
November 1, 2018: Talanta
https://www.readbyqxmd.com/read/30075399/simultaneous-determination-of-ten-nonsteroidal-anti-inflammatory-drugs-from-drinking-water-surface-water-and-wastewater-using-micro-uhplc-ms-ms-with-on-line-spe-system
#14
Zoltán Márta, Balázs Bobály, Jenő Fekete, Balázs Magda, Tímea Imre, Pál Tamás Szabó
A simple, accurate and sensitive micro UHPLC-MS/MS method was developed and validated for the simultaneous determination of 10 nonsteroidal anti-inflammatory drugs (NSAIDs) from different environmental matrices. The micro LC ‒ on-line SPE method described in this study allowed to determine the selected drugs at ultra-trace levels without the most commonly used complex off-line SPE sample preparation procedures. The presented method is capable of reaching satisfactory low LOQ values with analysing the sample directly after being diluted with water...
October 25, 2018: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/30063973/analysis-of-chemical-composition-and-in-vitro-antidermatophyte-activity-of-ethanol-extracts-of-dryopteris-fragrans-l-schott
#15
Xueping Liu, Jiayuan Liu, Tao Jiang, Lili Zhang, Yixi Huang, Jiangfan Wan, Guoqiang Song, Haoqi Lin, Zhibin Shen, Chunping Tang
ETHNOPHARMACOLOGICAL RELEVANCE: Dryopteris fragrans (L.) Schott is a deciduous perennial herb, which has been used traditionally for treatment of ringworm infections and others skin diseases in the north of China. AIM OF THE STUDY: To characterize the chemical composition, evaluate the antifungal activity and explore possible mechanisms about action of ethanol extracts of D. fragrans. MATERIALS AND METHODS: The chemical components in the ethanol extracts of D...
November 15, 2018: Journal of Ethnopharmacology
https://www.readbyqxmd.com/read/30048799/uv-spectroscopy-and-least-square-matching-for-high-throughput-discrimination-of-taxanes-in-commercial-formulations-and-compounded-bags
#16
E Jaccoulet, C Boughanem, L Auduteau, P Prognon, E Caudron
The need for high-throughput quality control of pharmaceuticals after compounding is often required before the treatment of the patients. Ultra-fast analysis using flow injection analysis coupled to UV spectroscopy and least square matching was assessed for the simultaneous quantification and identification of three therapeutic taxanes after dilution in physiological saline (cabazitaxel, docetaxel, and paclitaxel). In-depth preliminary analysis of the zero and first order UV spectra of the taxanes using principal component analysis (PCA) allowed us focusing on relevant spectral range with very low formulation influence...
October 15, 2018: European Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/30029353/nano-liquid-chromatography-high-resolution-mass-spectrometry-for-the-identification-of-metabolites-of-the-two-new-psychoactive-substances-n-ortho-methoxybenzyl-3-4-dimethoxyamphetamine-and-n-ortho-methoxybenzyl-4-methylmethamphetamine
#17
Achim T Caspar, Markus R Meyer, Folker Westphal, Armin A Weber, Hans H Maurer
Among the emerging new psychoactive substances (NPS), compounds carrying an N-ortho-methoxybenzyl substituent, the so-called NBOMes, represented a highly potent group of new hallucinogens. Recently, 3,4-dimethoxyamphetamine (3,4-DMA)-NBOMe and 4-methylmethamphetamine (4-MMA)-NBOMe occurred, but no data on their pharmacokinetics were available. According to other NBOMes, they are expected to be extensively metabolized. For detection and identification of their phase I and II metabolites, nano liquid chromatography coupled to high resolution tandem mass spectrometry (nanoLC-HRMS/MS) was used...
October 1, 2018: Talanta
https://www.readbyqxmd.com/read/30024785/dna-electromagnetic-properties-and-interactions-an-investigation-on-intrinsic-bioelectromagnetism-within-dna
#18
Masroor Hassan Bukhari, Salma Batool, Dr Yasir Raza, Omar Bagasra, Abbas Rizvi, Asifa Shah, Tashmeem Razzaki, Tipu Sultan
The question whether intrinsic bioelectromagnetism exists within DNA or not is an important and so far unexplored area of biology. We carried out a study of isolated genetic material, utilizing both prokaryotic and eukaryotic DNA, to measure any possible intrinsic electromagnetic effects or fields emanated within the molecules. Studies were carried out with extremely sensitive ultra-low-noise trans-impedance amplifiers and a high-precision data acquisition system to record any possible faintest electromagnetic signals from the concentrated, as well as diluted DNA, in vitro...
2018: Electromagnetic Biology and Medicine
https://www.readbyqxmd.com/read/30008504/magnetic-hydrophobic-charge-induction-adsorbents-for-the-recovery-of-immunoglobulins-from-antiserum-feedstocks-by-high-gradient-magnetic-fishing
#19
Cláudia Sg Gomes, Adedayo Fashina, Alfred Fernández-Castané, Timothy W Overton, Timothy J Hobley, Eirini Theodosiou, Owen Rt Thomas
BACKGROUND: The extraction of biopharmaceuticals from plasma and serum often employs overly complicated antiquated procedures that can inflict serious damage on especially prone protein targets and which afford low purification power and overall yields. This paper describes systematic development of a high-gradient magnetic fishing process for recovery of immunoglobulins from unclarified antiserum. RESULTS: Non-porous superparamagnetic particles were transformed into hydrophobic-charge induction adsorbents and then used to recover immunoglobulins from rabbit antiserum feedstocks...
July 2018: Journal of Chemical Technology and Biotechnology
https://www.readbyqxmd.com/read/29974743/super-resolution-imaging-of-clickable-graphene-nanoribbons-decorated-with-fluorescent-dyes
#20
Dharati Joshi, Meghan Hauser, Gregory Veber, Alexandra Berl, Ke Xu, Felix R Fischer
The functional integration of atomically defined graphene nanoribbons (GNRs) into single-ribbon electronic device architectures has been limited by access to nondestructive high-resolution imaging techniques that are both compatible with common supports such as Si or Si/SiO2 wafers and capable of resolving individual ribbons in dilute samples. Conventional techniques such as scanning probe (AFM, STM) or electron microscopy (SEM, TEM) have been restricted by requisite sample preparation techniques that are incompatible with lithographic device fabrication...
August 1, 2018: Journal of the American Chemical Society
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