Search results for "Spectrometry"
showing 10 items of 3206 documents
Validation of (68)Ge/(68)Ga generator processing by chemical purification for routine clinical application of (68)Ga-DOTATOC.
2008
Abstract Introduction Imaging of somatostatin receptor expressing tumours has been greatly enhanced by the use of 68 Ga-DOTATOC and PET/CT. Methods In this work, a purification method for the 68 Ge/ 68 Ga generator eluate and a method to produce 68 Ga-DOTATOC suitable for clinical use were evaluated. The generator eluate was purified and concentrated on a cation-exchange cartridge in HCl/acetone media. The efficacy of this procedure in eliminating metal impurities from the 68 Ga solution was investigated by ICP-MS. The radiotracer quality was evaluated by radio-TLC, GC and γ-ray spectrometry. Results 68 Ga-DOTATOC preparations ( n =33) were carried out with a mean synthesis yield of 59.3±2.…
Patterns of Carbon-Bound Exogenous Compounds in Patients with Lung Cancer and Association with Disease Pathophysiology.
2021
Abstract Asymptomatic anthracosis is the accumulation of black carbon particles in adult human lungs. It is a common occurrence, but the pathophysiologic significance of anthracosis is debatable. Using in situ high mass resolution matrix-assisted laser desorption/ionization (MALDI) fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometry imaging analysis, we discovered noxious carbon-bound exogenous compounds, such as polycyclic aromatic hydrocarbons (PAH), tobacco-specific nitrosamines, or aromatic amines, in a series of 330 patients with lung cancer in highly variable and unique patterns. The characteristic nature of carbon-bound exogenous compounds had a strong association wi…
Large-scale proteomic identification of S100 proteins in breast cancer tissues
2010
Abstract Background Attempts to reduce morbidity and mortality in breast cancer is based on efforts to identify novel biomarkers to support prognosis and therapeutic choices. The present study has focussed on S100 proteins as a potentially promising group of markers in cancer development and progression. One reason of interest in this family of proteins is because the majority of the S100 genes are clustered on a region of human chromosome 1q21 that is prone to genomic rearrangements. Moreover, there is increasing evidence that S100 proteins are often up-regulated in many cancers, including breast, and this is frequently associated with tumour progression. Methods Samples of breast cancer t…
Extensive phytocannabinoid profiles of seized cannabis and cannabis-based medicines – Identification of potential distinguishing markers
2021
As the frequency of cannabis-based therapy increases, the ability to distinguish intake of cannabis-based medicines from recreational cannabis use becomes desirable. Minor cannabinoids have been suggested to indicate recreational cannabis use in biological matrices but are unreliable when presumably also present in directly plantderived medicines. Thus, for therapeutics such as medical cannabis, Sativex® and Dronabinol, a more thorough investigation of cannabinoid profiles is required to identify possible distinguishing markers. In this study, 16 phytocannabinoids were quantified in samples of seized and medical cannabis, Sativex® and Dronabinol from two different manufacturers, using a val…
Increased endocannabinoid levels reduce the development of precancerous lesions in the mouse colon
2007
Colorectal cancer is an increasingly important cause of death in Western countries. Endocannabinoids inhibit colorectal carcinoma cell proliferation in vitro. In this paper, we investigated the involvement of endocannabinoids on the formation of aberrant crypt foci (ACF, earliest preneoplastic lesions) in the colon mouse in vivo. ACF were induced by azoxymethane (AOM); fatty acid amide hydrolase (FAAH) and cannabinoid receptor messenger ribonucleic acid (mRNA) levels were analyzed by the quantitative reverse transcription polymerase chain reaction (RT-PCR); endocannabinoid levels were measured by liquid chromatography-mass spectrometry; caspase-3 and caspase-9 expressions were measured by W…
Relating Hyperspectral Airborne Data to Ground Measurements in a Complex and Discontinuous Canopy
2015
The work described in this paper is aimed at validating hyperspectral airborne reflectance data collected during the Regional Experiments For Land-atmosphere EXchanges (REFLEX) campaign. Ground reflectance data measured in a vineyard were compared with airborne reflectance data. A sampling strategy and subsequent ground data processing had to be devised so as to capture a representative spectral sample of this complex crop. A linear model between airborne and ground data was tried and statistically tested. Results reveal a sound correspondence between ground and airborne reflectance data (R2 > 0.97), validating the atmospheric correction of the latter.
An automated and self-cleaning nano liquid chromatography mass spectrometry platform featuring an open tubular multi-hole crystal fiber solid phase e…
2017
An open tubular (OT) sample preparation/separation platform was developed. A multi-channel polymer layer open tubular (mPLOT) solid phase extraction (SPE) column was prepared by wall-coating the 126 channels (8μm inner diameter (ID) each) of a crystal fiber capillary with an organic polymer, namely poly(styrene-co-octadecene-co-divinylbenzene) (PS-OD-DVB). The mPLOT SPE was coupled on-line with a 10μm×2m poly(styrene-co-divinylbenzene) (PS-DVB) OT liquid chromatography column with nanospray mass spectrometry (OTLC-MS). Compared to using monolithic/particle-packed SPEs, mPLOT-SPE-OTLC allowed both fast loading and sufficient refocusing on the OT analytical column of small model compounds (su…
Gas—liquid chromatographic analyses
1984
Abstract The gas chromatography (GC) of n -alkyl acetates (CH 3 COOR), chloroacetates (CH 2 ClCOOR), dichloroacetates (CHCl 2 COOR) and trichloroacetates (CCl 3 COOR), where the alcohol chain length (R) varied between 1 and 8, and certain of their monochlorinated derivatives, 176 compounds altogether, has been studied on SE-30 and OV-351 glass capillary columns under the same operating conditions. The isomeric monochlorinated esters are eluted in direct order from the 1- chloro to the ω-chloro isomer, the separation of the isomers being complete on OV- 351. On SE-30, however, the peaks of the 6- and 7-chlorooctyl esters are partly overlapped. The separation of the mixtures of odd- and e…
Acrylate ester-based monolithic columns for capillary electrochromatography separation of triacylglycerols in vegetable oils
2011
Abstract A simple and reliable method for the evaluation of triacylglycerols (TAGs) in vegetable oils by capillary electrochromatography (CEC) with UV–Vis detection, using octadecyl acrylate (ODA) ester-based monolithic columns, has been developed. The percentages of the porogenic solvents in the polymerization mixture, and the mobile phase composition, were optimized. The optimum monolith was obtained at the following ratios: 40:60% (wt/wt) monomers/porogens, 60:40% (wt/wt) ODA/1,3-butanediol diacrylate and 23:77% (wt/wt) 1,4-butanediol/1-propanol (14 wt% 1,4-butanediol in the polymerization mixture). A satisfactory resolution between TAGs was achieved in less than 12 min with a 65:35 (v/v…
A critical appraisal of capillary electrochromatography.
2002
Although still in its infancy, CEC promises some advantages over competitive techniques for separating charged analytes including biomolecules.