Search results for "blood plasma"
showing 10 items of 162 documents
Ochratoxin A levels in the plasma of healthy blood donors from Valencia and estimation of exposure degree: comparison with previous national Spanish …
2010
Blood plasma levels of ochratoxin A, a toxic secondary metabolite of several fungal species belonging to the genera Aspergillus and Penicillium, were determined in 168 blood donors from the population of Valencia (Spain) using LC-FLD. In conjunction with blood collection, detailed information on diet was obtained by using a questionnaire that encompassed a wide range of products potentially contaminated with the toxin. The investigation revealed a detection frequency of 100%. Mean level was 1.09 microg OTA/l of plasma and concentrations ranged between 0.15 and 5.71 microg OTA/l of plasma. Men's levels were slightly higher than levels observed in women. Results were analysed by Spearman rank…
Partition coefficient, blood to plasma ratio, protein binding and short-term stability of 11-nor-Delta(9)-carboxy tetrahydrocannabinol glucuronide.
2002
11-Nor-Delta(9)-carboxy tetrahydrocannabinol glucuronide (THCCOOglu) is a major metabolite of tetrahydrocannabinol in blood. Despite its mass spectrometric identification already in 1980, further physicochemical data of THCCOOglu have not been established. Therefore, the octanol/buffer partition coefficient P and the blood to plasma ratio b/p for THCCOOglu concentrations of 100 and 500ng/ml were investigated. Protein binding of the glucuronide was established from spiked albumin solutions at a level of 250ng/ml as well as from authentic samples. The data were compared to those of 11-nor-Delta(9)-carboxy tetrahydrocannabinol (THCCOOH). In addition, the short-term stability of THCCOOglu in pl…
Cytokine Plasma Levels: Reliable Predictors for Radiation Pneumonitis?
2008
BackgroundRadiotherapy (RT) is the primary treatment modality for inoperable, locally advanced non-small-cell lung cancer (NSCLC), but even with highly conformal treatment planning, radiation pneumonitis (RP) remains the most serious, dose-limiting complication. Previous clinical reports proposed that cytokine plasma levels measured during RT allow to estimate the individual risk of patients to develop RP. The identification of such cytokine risk profiles would facilitate tailoring radiotherapy to maximize treatment efficacy and to minimize radiation toxicity. However, cytokines are produced not only in normal lung tissue after irradiation, but are also over-expressed in tumour cells of NSC…
Neuroprotective Potential of GDF11: Myth or Reality?
2019
In the brain, aging is accompanied by cellular and functional deficiencies that promote vulnerability to neurodegenerative disorders. In blood plasma from young and old animals, various factors such as growth differentiation factor 11 (GDF11), whose levels are elevated in young animals, have been identified. The blood concentrations of these factors appear to be inversely correlated with the age-related decline of neurogenesis. The identification of GDF11 as a “rejuvenating factor” opens up perspectives for the treatment of neurodegenerative diseases. As a pro-neurogenic and pro-angiogenic agent, GDF11 may constitute a basis for novel therapeutic strategies.
Determination of Human Granulocyte Elastase by the Immunoactivation Method on the Hitachi® 717 Automated Analyser
1991
This paper describes a fully mechanized homogeneous immunoassay using the immunoactivation method for the rapid and specific determination of human granulocyte elastase (EC 3.4.21.37) in plasma. The method uses anti-elastase antibody fragments from sheep, conjugated to horseradish peroxidase. These enzyme-antibody conjugates bind to the elastase-alpha 1-proteinase inhibitor complex present in plasma. A separate sample blank with non-specific sheep antibody fragments conjugated to horseradish peroxidase corrects for errors introduced by the sample matrix. Measurements were performed with the clinical chemistry analyser Hitachi 717. A single determination can be performed in 10 min, requiring…
Rewarding Properties of Testosterone in Intact Male Mice
2000
The present study examined the rewarding properties of 4-androsten-17β-ol-3-one testosterone in intact male mice using the conditioned place preference (CPP) technique. In Experiment 1, the pharmacokinetics of 0.8 and 1.2 mg/kg of testosterone were studied to determine the most appropriate temporal interval to test behavior. Additionally, the locomotor activity was recorded to control a possible interfering effect on CPP. The maximum testosterone concentration was registered at 45 min of administration, and no effects on activity were found. In Experiment 2, three groups of male OF-1 mice received four pairings of the least-preferred compartment with testosterone (0.8, 1, or 1.2 mg/kg, SC) …
Formation of N-methylnicotinamide in the brain from a dihydropyridine-type prodrug
1999
The enhancement of brain choline levels is a possible therapeutic option in neurodegenerative diseases; however, brain choline levels are held within narrow limits by homeostatic mechanisms including the rapid clearance of excess choline from the brain. The present study tests whether N-methylnicotinamide (NMN), an inhibitor of the outward transport of choline from the brain, can elevate brain choline levels in vivo. As NMN does not cross the blood-brain barrier, we synthesized and administered the brain-permeable prodrug, 1,4-dihydro-N-methyl-nicotinamide (DNMN), and tested its effect on the levels of NMN and choline in brain extracellular fluid, using the microdialysis procedure. Administ…
Moderate-Vigorous Physical Activity across Body Mass Index in Females : Moderating Effect of Endocannabinoids and Temperament
2014
Altres ajuts: This manuscript was supported by grants from Instituto Salud Carlos III (FIS PI11/210 and CIBERobn). Sarah Sauchelli is recipient of a pre-doctoral Grant (2013-17) by IDIBELL. Jose C. Fernández-García is recipient of a 'Rio Hortega' contract from 'Instituto de Salud Carlos III', Madrid, Spain (CM12/00059). The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. Endocannabinoids and temperament traits have been linked to both physical activity and body mass index (BMI) however no study has explored how these factors interact in females. The aims of this cross-sectional study were to 1) examine differences…
Column switching and high-performance liquid chromatography in the analysis of amitriptyline, nortriptyline and hydroxylated metabolites in human pla…
1992
A column-switching system for the direct injection of plasma or serum samples, followed by isocratic high-performance liquid chromatography and ultraviolet detection, is described for the simultaneous quantitation of the tricyclic antidepressant amitriptyline, its demethylated metabolite nortriptyline and the E- and Z-isomers of 10-hydroxyamitriptyline and 10-hydroxynortriptyline. The method included adsorption of amitriptyline and metabolites on a reversed-phase C8 clean-up column (10 microns; 20 mm x 4.6 mm I.D.), washing of unwanted material to waste and, after on-line column-switching, separation on a cyanopropyl analytical column (5 microns; 250 mm x 4.6 mm I.D.). The compounds of inte…
Anti-prothrombin autoantibodies enriched after infection with SARS-CoV-2 and influenced by strength of antibody response against SARS-CoV-2 proteins
2021
Antiphospholipid antibodies (aPL), assumed to cause antiphospholipid syndrome (APS), are notorious for their heterogeneity in targeting phospholipids and phospholipid-binding proteins. The persistent presence of Lupus anticoagulant and/or aPL against cardiolipin and/or β2-glycoprotein I have been shown to be independent risk factors for vascular thrombosis and pregnancy morbidity in APS. aPL production is thought to be triggered by–among other factors–viral infections, though infection-associated aPL have mostly been considered non-pathogenic. Recently, the potential pathogenicity of infection-associated aPL has gained momentum since an increasing number of patients infected with Severe Acu…