Search results for "high [multiplicity]"
showing 10 items of 1570 documents
Identification of 5,6,7,8-tetrahydropterin and 5,6,7,8-tetrahydrobiopterin in Drosophila melanogaster.
1988
Summary Using reversed-phase high-performance liquid chromatography with electrochemical detection we have demonstrated the occurrence of 5,6,7,8-tetrahydropterin and 5,6,7,8-tetrahydrobiopterin in Drosophila melanogaster . The former is the first time that has been detected in vivo . The identification has been based on the retention times, hydrodinamic voltagrams and the differential concentration in three strains of Drosophila melanogaster . Compared to the wild type, the Punch 2 mutant has diminished levels of both pteridines, whereas Henna-recessive 3 lacks completely tetrahydropterin and has increased levels of tetrahydrobiopterin, as expected according to their biochemical lesions.
Stimulatory and inhibitory effects of ethanol on hippocampal acetylcholine release
1998
Using the microdialysis technique and sensitive HPLC procedures for the determination of acetylcholine (ACh) and ethanol, we investigated the release of ACh in rat hippocampus after acute ethanol administration. Systemic administration of ethanol (0.8 and 2.4 g/kg i.p.) led to peak ethanol concentrations of 21 and 42 mM in the hippocampus, respectively. The high dose caused a long-lasting inhibition of basal ACh release by up to 33%. Local infusion of scopolamine (1 microM) enhanced hippocampal ACh release up to eightfold in the presence of neostigmine (10 microM), and this stimulated release was also inhibited after systemic ethanol administration (by up to 45%). The low dose of ethanol (0…
Analysis of LSD in human body fluids and hair samples applying ImmunElute columns.
2000
Immunoaffinity extraction units (LSD ImmunElute) are commercially available for the analysis of lysergic acid diethylamide (LSD) in urine. The ImmunElute resin contains immobilized monoclonal antibodies to LSD. We applied the ImmunElute procedure to serum and also to human hair samples. For hair analysis the samples were first extracted with methanol under sonication. The extracts were then purified using the ImmunElute resin. LSD analysis was carried out with HPLC and fluorescence detection. The immunoaffinity extraction provides highly purified extracts for chromatographic analysis. The limit of detection (signal-to-noise ratio = 3) has been determined to be < 50 pg regardless of which sa…
Advanced Glycation End Products: New Clinical and Molecular Perspectives
2021
Diabetes mellitus (DM) is considered one of the most massive epidemics of the twenty-first century due to its high mortality rates caused mainly due to its complications; therefore, the early identification of such complications becomes a race against time to establish a prompt diagnosis. The research of complications of DM over the years has allowed the development of numerous alternatives for diagnosis. Among these emerge the quantification of advanced glycation end products (AGEs) given their increased levels due to chronic hyperglycemia, while also being related to the induction of different stress-associated cellular responses and proinflammatory mechanisms involved in the progression …
Postmortem distribution of dihydrocodeine and metabolites in a fatal case of dihydrocodeine intoxication.
1998
A report of a fatal dihydrocodeine ingestion under substitution therapy is given. Quantitation of dihydrocodeine, dihydromorphine, N-nordihydrocodeine, dihydrocodeine-6-, dihydromorphine-6- and dihydromorphine-3-glucuronide was performed simultaneously after solid-phase extraction prior to HPLC analysis, and the analytes were detected using their native fluorescence. Postmortem concentrations of blood samples from different sampling sites as well as from liver, kidney and cerebrum are reported. A hair sample was investigated to prove long-term use of the substitute drug. Site-to-site differences of the analytes from blood samples were very small. The partition behavior of the opioid glucuro…
Direct sunlight facility for testing and research in HCPV
2014
A facility for testing different components for HCPV application has been developed in the framework of "Fotovoltaico ad Alta Efficienza" (FAE) project funded by the Sicilian Regional Authority (PO FESR Sicilia 2007/2013 4.1.1.1). The testing facility is equipped with an heliostat providing a wide solar beam inside the lab, an optical bench for mounting and aligning the HCPV components, electronic equipments to characterize the I-V curves of multijunction cells operated up to 2000 suns, a system to circulate a fluid in the heat sink at controlled temperature and flow-rate, a data logging system with sensors to measure temperatures in several locations and fluid pressures at the inlet and ou…
Endogenous role of epoxide-hydratase. Development of a steroid epoxide-hydratase assay and properties of the enzyme.
1979
A highly sensitive and rapid radiometric assay for the determination of specific epoxide hydratase activity with a steroid epoxide (16α, 17α-epoxy-1,3,5(10)-estratrien-3-ol, ‘estroxide’) has been developed. The unreacted substrate was separated from the product 1,3,5(10)-estratrien-3,16β,17α-triol by extraction into light petroleum. The product was then extracted into ethyl acetate and measured by scintillation spectrometry. Radiochromatography established that after subtraction of the blank the entire radioactivity measured in the ethyl acetate phase resulted from the product 1,3,5(10)-estratrien-3,16,17-triol, whilst high performance liquid chromatography with the four possible isomers of…
Digital performance improvements of a CdTe pixel detector for high flux energy-resolved X-ray imaging
2015
Abstract Photon counting detectors with energy resolving capabilities are desired for high flux X-ray imaging. In this work, we present the performance of a pixelated Schottky Al/p-CdTe/Pt detector (4×4) coupled to a custom-designed digital readout electronics for high flux measurements. The detector (4×4×2 mm 3 ) has an anode layout based on an array of 16 pixels with a geometric pitch of 1 mm (pixel size of 0.6 mm). The 4-channel readout electronics is able to continuously digitize and process the signals from each pixel, performing multi-parameter analysis (event arrival time, pulse shape, pulse height, pulse time width, etc.) even at high fluxes and at different throughput and energy re…
Poly(lactic acid)/carvacrol-based materials: preparation, physicochemical properties, and antimicrobial activity
2020
The current demand for new antimicrobial systems has stimulated research for the development of poly(lactic acid)/carvacrol (PLA/CAR)-based materials able to hinder the growth and spread of microorganisms. The eco-friendly characteristics of PLA and cytocompatibility make it very promising in the perspective of green chemistry applications as material for food and biomedical employments. The broad-spectrum biological and pharmacological properties of CAR, including antimicrobial activity, make it an interesting bioactive molecule that can be easily compounded with PLA by adopting the same techniques as those commonly used for PLA manufacturing. This review critically discusses the most comm…
Application of molecular topology to the prediction of antiparasitic activity against Giardia intestinalis and Trichomonas vaginalis of 2-Acylamino-n…
2020
Giardia intestinalis y Trichomonas vaginalis destacan por su importancia clínica. G. intestinalis causa la giardiosis, una parasitosis de gran importancia epidemiológica y clínica por presentar una elevada prevalencia. T. vaginalis causa la tricomoniasis, la enfermedad de transmisión sexual (ETS) no viral con mayor incidencia del mundo. Ambas parasitosis comparten el mismo tratamiento farmacológico: los nitroimidazoles. Se ha aplicado la topología molecular en la búsqueda de derivados del 2-Acylamino-nitro-1,3-tiazol con actividad antiparasitaria frente a G. intestinalis y T. vaginalis . Con el análisis lineal discriminante se obtuvo un modelo capaz de clasificar correctamente el 92,85 % de…