keyword
MENU ▼
Read by QxMD icon Read
search

Analytical Techniques

keyword
https://www.readbyqxmd.com/read/28636663/an-endophytic-basidiomycete-grammothele-lineata-isolated-from-corchorus-olitorius-produces-paclitaxel-that-shows-cytotoxicity
#1
Avizit Das, Mohammad Imtiazur Rahman, Ahlan Sabah Ferdous, Al- Amin, Mohammad Mahbubur Rahman, Nilufar Nahar, Md Aftab Uddin, Mohammad Riazul Islam, Haseena Khan
Grammothele lineata, an endophyte isolated in our laboratory from jute (Corchorus olitorius acc. 2015) was found to be a substantial paclitaxel producer. Taxol and its related compounds, produced by this endophyte were extracted by growing the fungus in simple nutrient media (potato dextrose broth, PDB). Taxol was identified and characterized by different analytical techniques (TLC, HPLC, FTIR, LC-ESI-MS/MS) following its extraction by ethyl acetate. In PDB media, this fungus was found to produce 382.2 μgL-1 of taxol which is about 7...
2017: PloS One
https://www.readbyqxmd.com/read/28636332/new-insights-into-the-wavelength-dependence-of-maldi-mass-spectrometry
#2
Marcel Niehaus, Andreas Schnapp, Annika Koch, Jens Soltwisch, Klaus Dreisewerd
The interplay between the wavelength of the laser and the absorption profile of the matrix constitutes a crucial factor in matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). Numerous studies have shown that typically best analytical results are obtained if the laser wavelength matches the UV absorption band of the matrix in the solid state well. However, many powerful matrices exhibit peak absorptions which differ notably from the standard MALDI laser wavelengths of 337, 349, and 355 nm, respectively...
June 21, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28636328/structural-dynamics-of-native-like-ions-in-the-gas-phase-results-from-tandem-ion-mobility-of-cytochrome-c
#3
Samuel J Allen, Rachel M Eaton, Matthew F Bush
Ion mobility (IM) is a gas-phase separation technique that is used to determine the collision cross sections of native-like ions of proteins and protein complexes, which are in turn used as restraints for modeling the structures of those analytes in solution. Here, we evaluate the stability of native-like ions using tandem IM experiments implemented using Structures for Lossless Ion Manipulations (SLIM). In this implementation of tandem IM, ions undergo a first dimension of IM up to a switch that is used to selectively transmit ions of a desired mobility...
June 21, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28636327/maldi-ms-guided-liquid-microjunction-extraction-for-ce-esi-ms-analysis-of-single-pancreatic-islet-cells
#4
Troy J Comi, Monika A Makurath, Marina C Philip, Stanislav S Rubakhin, Jonathan V Sweedler
The ability to characterize chemical heterogeneity in biological structures is essential to understanding cellular level function in both healthy and diseased states, but these variations remain difficult to assess using a single analytical technique. While mass spectrometry (MS) provides sufficient sensitivity to measure many analytes from volume-limited samples, each type of mass spectrometric analysis uncovers only a portion of the complete chemical profile of a single cell. Matrix-assisted laser desorp-tion/ionization (MALDI) MS and capillary electrophoresis electrospray ionization (CE-ESI)-MS are complementary analytical platforms frequently utilized for single cell analysis...
June 21, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28635619/on-the-importance-of-accurate-quantification-of-individual-volatile-metabolites-in-exhaled-breath
#5
David Smith, Patrik Spanel
It is argued that shortcomings of certain approaches to breath analysis research based on superficial interpretation of non-quantitative data are inadvertently inhibiting the progression of non-invasive breath analysis into clinical practice. The objective of this perspective is to suggest more clinically profitable approaches to breath research. Thus, following a discourse on the challenges and expectations in breath research, a brief indication is given of the analytical techniques currently used for the analysis of very humid exhaled breath...
June 21, 2017: Journal of Breath Research
https://www.readbyqxmd.com/read/28634759/current-applications-of-high-resolution-mass-spectrometry-for-the-analysis-of-new-psychoactive-substances-a-critical-review
#6
REVIEW
Daniel Pasin, Adam Cawley, Sergei Bidny, Shanlin Fu
The proliferation of new psychoactive substances (NPS) in recent years has resulted in the development of numerous analytical methods for the detection and identification of known and unknown NPS derivatives. High-resolution mass spectrometry (HRMS) has been identified as the method of choice for broad screening of NPS in a wide range of analytical contexts because of its ability to measure accurate masses using data-independent acquisition (DIA) techniques. Additionally, it has shown promise for non-targeted screening strategies that have been developed in order to detect and identify novel analogues without the need for certified reference materials (CRMs) or comprehensive mass spectral libraries...
June 20, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28634456/absolute-and-relative-training-load-and-its-relation-to-fatigue-in-football
#7
Unai Zurutuza, Julen Castellano, Ibon Echeazarra, David Casamichana
The aim of the study was to assess the relationship of external and internal training load (TL) indicators with the objective and subjective fatigue experienced by 15 semi-professional football players, over eight complete weeks of the competition period in the 2015-2016 season, which covered microcycles from 34th to 41st. The maximum heart rate (HRmax) and maximum speed (Vmax) of all the players were previously measured in specific tests. The TL was monitored via questionnaires on rating of perceived exertion (RPE), pulsometers and GPS devices, registering the variables: total distance (TD), player load 2D (PL2D), TD at >80% of the Vmax (TD80), TD in deceleration at < -2 m⋅sec-2 (TDD <-2), TD in acceleration >2 m⋅sec(-2) (TDA >2), Edwards (ED), time spent at between 50 and 80% (50-80% HRmax), 80-90% (80-90% HRmax), and >90% of the HRmax (>90% HRmax), and RPE both respiratory/thoracic (RPEres) and leg/muscular (RPEmus)...
2017: Frontiers in Psychology
https://www.readbyqxmd.com/read/28634067/magnetic-graphene-coated-inorganic-organic-hybrid-nanocomposite-for-enhanced-preconcentration-of-selected-pesticides-in-tomato-and-grape
#8
Hamid Rashidi Nodeh, Hassan Sereshti, Hamid Gaikani, Muhammad Afzal Kamboh, Zahra Afsharsaveh
The new magnetic graphene based hybrid silica-N-[3-(trimethoxysilyl)propyl]ethylenediamine (MG@SiO2-TMSPED) nanocomposite was synthesized via sol-gel process, and used as an effective adsorbent in magnetic solid phase extraction (MSPE) of three selected pesticides followed by gas chromatography micro-electron capture detection (GC-μECD). The adsorbent was characterized using Fourier transform-infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET), Barrett-Joyner-Halenda (BJH), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDXS) techniques...
June 13, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28631911/-the-study-of-mineral-composition-and-structure-of-uroliths-in-the-residents-of-tomsk-district-tomsk
#9
O A Sevostyanova, V S Boshchenko, V K Osadchii, V P Parnachev, A K Polienko
AIM: To successfully treat and prevent urolithiasis, the composition and structure of uroliths should be examined using modern analytical techniques. For a long time, studies of the biomineral formation in the human body have been conducted exclusively in the field of medicine. The main attention has been paid to the diagnosis and treatment of diseases leading to the occurrence of pathogenic formations. At the same time, it is quite obvious that it is important to have a clear idea about the causes of pathogenic formations, the mechanisms for their further formation, composition and structure...
June 2017: Urologii︠a︡
https://www.readbyqxmd.com/read/28630942/antimalarial-drugs-and-the-prevalence-of-mental-and-neurological-manifestations-a-systematic-review-and-meta-analysis
#10
Mary A Bitta, Symon M Kariuki, Clifford Mwita, Samson Gwer, Leah Mwai, Charles R J C Newton
Background: Antimalarial drugs affect the central nervous system, but it is difficult to differentiate the effect of these drugs from that of the malaria illness. We conducted a systematic review to determine the association between anti-malarial drugs and mental and neurological impairment in humans.  Methods: We systematically searched online databases, including Medline/PubMed, PsychoInfo, and Embase, for articles published up to 14th July 2016. Pooled prevalence, heterogeneity and factors associated with prevalence of mental and neurological manifestations were determined using meta-analytic techniques...
2017: Wellcome Open Research
https://www.readbyqxmd.com/read/28630482/circadian-and-circatidal-clocks-control-the-mechanism-of-semilunar-foraging-behaviour
#11
James F Cheeseman, Rachel M Fewster, Michael M Walker
How animals precisely time behaviour over the lunar cycle is a decades-old mystery. Experiments on diverse species show this behaviour to be endogenous and under clock control but the mechanism has remained elusive. We present new experimental and analytical techniques to test the hypotheses for the semilunar clock and show that the rhythm of foraging behaviour in the intertidal isopod, Scyphax ornatus, can be precisely shifted by manipulating the lengths of the light/dark and tidal cycles. Using light T-cycles (Tcd) the resultant semilunar beat period undergoes shifts from 14...
June 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28630409/two-dimensional-fluorescence-spectroscopy-of-uranium-isotopes-in-femtosecond-laser-ablation-plumes
#12
Mark C Phillips, Brian E Brumfield, Nicole LaHaye, Sivanandan S Harilal, Kyle C Hartig, Igor Jovanovic
We demonstrate measurement of uranium isotopes in femtosecond laser ablation plumes using two-dimensional fluorescence spectroscopy (2DFS). The high-resolution, tunable CW-laser spectroscopy technique clearly distinguishes atomic absorption from (235)U and (238)U in natural and highly enriched uranium metal samples. We present analysis of spectral resolution and analytical performance of 2DFS as a function of ambient pressure. Simultaneous measurement using time-resolved absorption spectroscopy provides information on temporal dynamics of the laser ablation plume and saturation behavior of fluorescence signals...
June 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28629976/mapbot-meta-analytic-parcellation-based-on-text-and-its-application-to-the-human-thalamus
#13
Rui Yuan, Paul A Taylor, Tara L Alvarez, Durga Mishra, Bharat B Biswal
Meta-analysis of neuroimaging results has proven to be a popular and valuable method to study human brain functions. A number of studies have used meta-analysis to parcellate distinct brain regions. A popular way to perform meta-analysis is typically based on the reported activation coordinates from a number of published papers. However, in addition to the coordinates associated with the different brain regions, the text itself contains considerably amount of additional information. This textual information has been largely ignored in meta-analyses where it may be useful for simultaneously parcellating brain regions and studying their characteristics...
June 16, 2017: NeuroImage
https://www.readbyqxmd.com/read/28629589/physical-exercise-and-dna-injury-good-or-evil
#14
Elisa Danese, Giuseppe Lippi, Fabian Sanchis-Gomar, Giorgio Brocco, Manfredi Rizzo, Maciej Banach, Martina Montagnana
Regular, low-intensity physical activity is currently advocated for lowering the risk of developing many acute and especially chronic diseases. However, several lines of evidence attest that strenuous exercise may enhance inflammation and trigger the generation of free radical-mediated damage, thus overwhelming the undisputable benefits of regular, medium-intensity physical activity. Since reactive oxygen species are actively generated during high-intensity exercise, and these reactive compounds are known to impact DNA stability, we review here the current evidence about strenuous exercise and DNA injury...
2017: Advances in Clinical Chemistry
https://www.readbyqxmd.com/read/28628967/post-bionian-developments-in-psychoanalytic-field-theory-the-contributions-of-antonino-ferro-and-giuseppe-civitarese
#15
S Montana Katz
The Bi-Personal Field: Experiences in Child Psychoanalysis. By Antonino Ferro. New York: Routledge, 1992 (1999). 232 pp. The Intimate Room: Theory and Technique of the Analytic Field. By Giuseppe Civitarese. New York: Routledge, 2008 (2010). 240 pp. The Necessary Dream: New Theories and Techniques of Interpretation in Psychoanalysis. By Giuseppe Civitarese; translated by Ian Harvey. London: Karnac, 2013 (2014). 246 pp. The Analytic Field and Its Transformations. By Antonino Ferro and Giuseppe Civitarese. London: Karnac, 2015...
April 2017: Psychoanalytic Quarterly
https://www.readbyqxmd.com/read/28628838/validated-uplc-ms-ms-method-for-simultaneous-quantification-of-eight-saikosaponins-in-rat-plasma-application-to-a-comparative-pharmacokinetic-study-in-depression-rats-after-oral-administration-of-extracts-of-raw-and-vinegar-baked-bupleuri-radix
#16
Tianli Lei, Dandan Zhang, Kun Guo, Mingxiao Li, Chongning Lv, Jing Wang, Lingyun Jia, Jincai Lu
A sensitive and efficient UPLC-MS/MS method was developed and validated for simultaneous quantification of eight saikosaponins (SSa, SSb1, SSb2, SSb3, SSb4, SSc, SSd and SSf) in rat plasma. Furthermore, comparative pharmacokinetic profiles of these sakosaponins were investigated, following oral administration of extracts of raw and vinegar-baked Bupleuri Radix to depression rats. Biosamples were processed with liquid-liquid extraction technique using ethyl acetate. Chromatographic separation was accomplished on Waters BEH C18 UPLC column...
June 16, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28628243/using-ultrahigh-resolution-mass-spectrometry-and-toxicity-identification-techniques-to-characterize-the-toxicity-of-oil-sands-process-affected-water-the-case-for-classical-naphthenic-acids
#17
Sarah A Hughes, Ashley Mahaffey, Bryon Shore, Josh Baker, Bruce Kilgour, Christine Brown, Kerry M Peru, John V Headley, Howard C Bailey
Previous assessments of oil sands process-affected water (OSPW) toxicity were hampered by lack of high-resolution analytical analysis, use of non-standard toxicity methods, and variability between OSPW samples. We integrated ultrahigh-resolution mass spectrometry with a Toxicity Identification Evaluation (TIE) approach to quantitatively identify the primary cause of acute toxicity of OSPW to rainbow trout (Oncorhynchus mykiss). The initial characterization of OSPW toxicity indicated that toxicity was associated with non-polar organic compounds, and toxicant(s) were further isolated within a range of discrete methanol fractions that were then subjected to Orbitrap mass spectrometry to evaluate the contribution of naphthenic acid (NA) fraction compounds to toxicity...
June 19, 2017: Environmental Toxicology and Chemistry
https://www.readbyqxmd.com/read/28628219/application-of-swath-proteomics-to-mouse-biology
#18
Yibo Wu, Evan G Williams, Ruedi Aebersold
The quantitative measurement of the proteome has been shown to yield new insights into physiology and cell biology that cannot be determined from the genome and transcriptome because the quantitative relationship between transcriptome and proteome is complex. MS-based proteomics techniques, such as SWATH-MS, have recently advanced to the point at which they may be reliably applied by biologists who are not specialists in mass spectrometry. Here we provide standard protocols for preparation of tissue samples for input into the SWATH-MS analytical pipeline...
June 19, 2017: Current Protocols in Mouse Biology
https://www.readbyqxmd.com/read/28627877/detection-and-quantification-of-hydrogen-peroxide-in-aqueous-solutions-using-chemical-exchange-saturation-transfer-cest
#19
David Ryoo, Xiang Xu, Yuguo Li, Joel Tang, Jia Zhang, Peter C M van Zijl, Guanshu Liu
The development of new analytical methods to accurately quantify hydrogen peroxide is of great interest. In the current study, we developed a new magnetic resonance (MR) method for noninvasively quantifying hydrogen peroxide (H2O2) in aqueous solutions based on chemical exchange saturation transfer (CEST), an emerging MRI contrast mechanism. Our method can detect H2O2 by its specific CEST signal at ~6.2 ppm downfield from water resonance, with more than 1000 times signal amplification compared to the direct NMR detection...
June 19, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28627833/comparison-of-the-analytical-performance-between-cobas-egfr-assay-and-pcr-clamp-method-in-the-detection-of-egfr-mutations-in-japanese-non-small-cell-lung-cancer-patients
#20
Tomohiko Ai, Maiko Yuri, Yoko Tabe, Atsushi Kakimoto, Soji Morishita, Koji Tsuchiya, Kazuya Takamochi, Yuzo Kodama, Fumiyuki Takahashi, Misawa Shigeki, Takashi Horii, Kenji Suzuki, Kazuhisa Takahashi, Takashi Miida, Akimichi Ohsaka
BACKGROUND: EGFR, a tyrosine-kinase, plays an important role in the progression of lung cancer. Since genetic abnormality of EGFR alters the effects of tyrosine-kinase inhibitors targeting EGFR, molecular analyses of EGFR have recently gained more attention in the treatment of lung cancer. However, several different techniques are available and which method is superior has not been determined. In this study, we compared two recently developed PCR-based techniques, PCR-clamp method and cobas EGFR assay...
May 1, 2017: Clinical Laboratory
keyword
keyword
2756
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"