Search results for " SPECT"
showing 10 items of 11464 documents
Noninvasive double confirmation of cocaine abuse.
2013
A double confirmation procedure, based on the combined application of Ion Mobility Spectrometry (IMS) and Infrared Spectroscopy (IR), has been developed for the noninvasive unambiguous identification of cocaine consume. The use of nasal mucus as a biological specimen for cocaine abuse confirmation has been proposed as an alternative to the use of blood and urine due to its noninvasive character and the presence of the parent compound instead of its metabolites. Sampling conditions, interferences caused by cutting agents and other substances, and limits of identification (LOI) and confirmation (LOC) have been deeply evaluated. The procedure combines the high sensitivity of the IMS to identif…
A comprehensive untargeted metabonomic analysis of human steatotic liver tissue by RP and HILIC chromatography coupled to mass spectrometry reveals i…
2011
Steatosis, or excessive accumulation of lipids in the liver, is a generally accepted previous step to the development of more severe conditions like nonalcoholic steatohepatitis, fibrosis, and cirrhosis. We aimed, to characterize the metabolic profile that defines simple steatosis in human tissue and to identify potential disturbances in the hepatic metabolism that could favor the switch to progressive liver damage. A total of 46 samples, 23 from steatotic and 23 from nonsteatotic human livers, were analyzed following a holistic LC-MS-based metabonomic analysis that combines RP and HILIC chromatographic separations. Multivariate statistical data analysis satisfactorily classified samples an…
Development and validation of a reliable method for studying the distribution pattern for opiates metabolites in brain
2012
Abstract Brain distribution pattern of “street” heroin metabolites (morphine and codeine) was investigated in two fatalities due to “acute narcotism”. A suitable sample pretreatment prior to solid-phase-extraction was developed to achieve a good recovery of the analytes and to eliminate the interfering species. After derivatization with MSTFA, samples were analyzed by GC/MS. Specificity, accuracy, precision and linearity of the method were evaluated; LOD and LOQ were, respectively, 10 ng/25 ng for morphine and 5 ng/10 ng for codeine. This method was applied to the analysis of six brain areas (hippocampus, frontal lobe, occipital lobe, nuclei, bulb and pons) coming from two cases of heroin-r…
Development of a Rapid LC-MS/MS Method for the Determination of Emerging Fusarium mycotoxins Enniatins and Beauvericin in Human Biological Fluids
2015
A novel method for the simultaneous determination of enniatins A, A1, B and B1 and beauvericin, both in human urine and plasma samples, was developed and validated. The method consisted of a simple and easy pretreatment, specific for each matrix, followed by solid phase extraction (SPE) and detection by high performance liquid chromatography-tandem mass spectrometry with an electrospray ion source. The optimized SPE method was performed on graphitized carbon black cartridges after suitable dilution of the extracts, which allowed high mycotoxin absolute recoveries (76%–103%) and the removal of the major interferences from the matrix. The method was extensively evaluated for plasma and urine …
Comparison of Urinary On-Site Immunoassay Screening and Gas Chromatography-Mass Spectrometry Results of 111 Patients With Suspected Poisoning Present…
2007
On-site tests based on immunoassay techniques are widely used for toxicologic screening analysis in patients with suspected poisoning. However, such assays usually have been validated using urine samples with known concentrations of the investigated substances. In the present investigation, on-site screening results were evaluated in a clinical setting. This was a retrospective study of patients with suspected poisoning from January to December 2003 in the emergency department of a tertiary urban hospital. Urine samples were analyzed using the Triage 8 panel and gas chromatography-mass spectrometry (GC-MS). A total of 111 patients were included (54 female, 57 male; average age 37.8 +/- 19.7…
Serum concentrations of persistent organic pollutants (POPs) in the inhabitants of a Sicilian city.
2012
Polychlorinated biphenyls (PCBs) and organochlorine pesticides are common environmental contaminants that have been associated with human health problems. OBJECTIVES: To assess serum concentrations of several organochlorine contaminants in general population living in a city with an ancient agricultural tradition and to identify possible exposure sources in Sicily. METHODS: A cross-sectional study was conducted on 101 individuals. Each participant answered a face-to-face questionnaire submitted by well-trained personnel and provided a serum sample which was analyzed for the concentrations of PCBs, HCB, HCHs and DDTs by using gas-chromatography coupled with mass spectrometry. RESULTS: HCB, p…
Urinary levels of enniatin B and its phase I metabolites: First human pilot biomonitoring study
2018
Abstract Enniatins (Enns) are mycotoxins produced by Fusarium spp. and are widely distributed contaminants of cereals and derivate products. Among the different identified enniatins, Enn B is the most relevant analogue in cereals in Europe. Therefore, the aim of this study was to investigate for the first time the occurrence of Enn B and Enn B phase I metabolites in 300 human urine samples throughout an ultrahigh-performance liquid chromatography-high resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) methodology. Three different sample preparation procedures were evaluated and salting-out liquid-liquid extraction showed satisfactory validation results. Enn B was quantified in 83.7% of sa…
Quantitative evaluation of oxidative stress status on peripheral blood in beta-thalassaemic patients by means of electron paramagnetic resonance spec…
2005
Summary High oxidative stress status (OSS) is known to be one of the most important factors determining cell injury and consequent organ damage in thalassaemic patients with secondary iron overload. Using an innovative hydroxylamine ‘radical probe’ capable of efficiently trapping majority of oxygen-radicals including superoxide we measured, by electron paramagnetic resonance (EPR) spectroscopy, OSS in peripheral blood of 38 thalassaemic patients compared with sex-/age-matched healthy controls. Thalassaemic patients showed sixfold higher EPR values of OSS than controls. Significantly higher EPR values of OSS were observed in those with a severe phenotype (thalassaemia major, transfusion-depe…
Evidence of Wallerian degeneration in normal appearing white matter in the early stages of relapsing-remitting multiple sclerosis
2003
Objective: Wallerian degeneration in normal appearing white matter in early relapsing-remitting multiple sclerosis (RRMS), and its correlation with the number of relapses and disease duration. Background Recent pathological studies have demonstrated Wallerian degeneration in normal appearing white matter (NAWM) in multiple sclerosis (MS), in established RRMS, and in chronic MS. However, the presence of Wallerian degeneration early in the disease and its correlation with relapse and with disease duration has not been studied. Methods: We performed proton magnetic resonance spectroscopic imaging in 21 MS patients, and 4 healthy controls, age and gender matched, aged under 45 years, with a max…
Asymmetric metabolic profile in mesial temporal lobes: Localized H-1 MR spectroscopy in healthy right-handed and non-right-handed subjects
1996
International audience; Abstract: PURPOSE: To determine a possible asymmetric metabolic profile in right-handed and non-right-handed healthy subjects by comparing proton spectra from temporal lobes. MATERIALS AND METHODS: Twenty-eight healthy adults (17 right-handers, 11 non-right-handers) underwent magnetic resonance (MR) imaging and single-voxel MR spectroscopy. N-acetylaspartate (NAA), choline (Cho), and creatine (Cr) peak areas were measured. RESULTS: Volume of hippocampal formations was larger on the right in right-handers (right volume: 4.04 cm(3) +/- 0.67 vs left volume: 3.84 cm(3) +/- 0.62; P = .00004) and in non-right-handers (right volume: 4.22 cm(3) +/- 0.78 vs left volume: 4.05 …