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Compounds Relevant (compound + relevant)

Distribution by Scientific Domains

Chemistry	50%

Selected Abstracts

Screening for the calstabin-ryanodine receptor complex stabilizers JTV-519 and S-107 in doping control analysis

DRUG TESTING AND ANALYSIS, Issue 1 2009
Mario Thevis
Abstract Recent studies outlined the influence of exercise on the stability of the skeletal muscle calstabin1-ryanodine receptor1-complex, which represents a major Ca2+ release channel. The progressive modification of the type-1 skeletal muscle ryanodine receptor (RyR1) combined with reduced levels of calstabin1 and phosphodiesterase PDE4D3 resulted in a Ca2+ leak that has been a suggested cause of muscle damage and impaired exercise capacity. The use of 1,4-benzothiazepine derivatives such as the drug candidates JTV-519 and S-107 enhanced rebinding of calstabin1 to RyR1 and resulted in significantly improved skeletal muscle function and exercise performance in rodents. Due to the fact that the mechanism of RyR1 remodelling under exercise conditions were proven to be similar in mice and humans, a comparable effect of JTV-519 and S-107 on trained athletes is expected, making the compounds relevant for doping controls. After synthesis of JTV-519, S-107, and a putative desmethylated metabolite of S-107, target compounds were characterized using nuclear magnetic resonance spectroscopy and electrospray ionization (ESI),high-resolution/high-accuracy Orbitrap mass spectrometry. Collision-induced dissociation pathways were suggested based on the determination of elemental compositions of product ions and H/D-exchange experiments. The most diagnostic product ion of JTV-519 was found at m/z 188 (representing the 4-benzyl-1-methyl piperidine residue), and S-107 as well as its desmethylated analog yielded characteristic fragments at m/z 153 and 138 (accounting for 1-methoxy-4-methylsulfanyl-benzene and 4-methoxy-benzenethiol residues, respectively). The analytes were implemented in existing doping control screening procedures based on liquid chromatography, multiple reaction monitoring and simultaneous precursor ion scanning modes using a triple quadrupole mass spectrometer. Validation items such as specificity, recovery (68,92%), lower limit of detection (0.1,0.2 ng/mL), intraday (5.2,18.5%) and interday (8.7,18.8%) precision as well as ion suppression/enhancement effects were determined. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Flow cytometry as a method for studying effects of stressors on primary rat neurons

JOURNAL OF NEUROSCIENCE RESEARCH, Issue 3 2005
H. Behbahani
Abstract The mechanisms associated with cell death have been an important focus for neurobiology research. In the present study, the methodology of flow cytometry was used to optimize quantification of the toxic effects of tumor necrosis factor-, (TNF-,), trans-4-hydroxy-2-nonenal (4-HNE), and aged amyloid-, (A,1,42) on rat primary cortical neurons. The fluorescent dyes annexin V-FITC and propidium iodide (PI) were used to identify populations of viable, early apoptotic, necrotic and late apoptotic cells by flow cytometry. Prior to exposure, the primary cultures showed 83% cell viability. Flow cytometry following labeling of cells with a specific neuronal marker, TUJ-1, revealed 82% pure neuronal populations, whereas approximately 7% were astrocytic as shown by glial fibrillary acidic protein positivity. Exposure of primary cultures to TNF-,, 4-HNE, and aged A,1,42 gave an increased number of early apoptotic cells. We show that flow cytometry is a suitable method for quantifying effects of different stressors on neurons in primary cultures. This technique could be useful for screening and testing of pharmacological compounds relevant to neurodegenerative disorders. © 2005 Wiley-Liss, Inc. [source]

Raman spectra of organic acids obtained using a portable instrument at ,5 °C in a mountain area at 2000 m above sea level

JOURNAL OF RAMAN SPECTROSCOPY, Issue 4 2010
J. Jehli
Abstract Well-resolved Raman spectra of organic acids were obtained with 785 nm excitation using a portable Raman instrument (Ahura First Defender XL) under low temperature ,5 °C atmospheric conditions at an altitude of 2000 m (Axamer Lizum, Innental, Austria). The portable Raman spectrometer tested in this setting permits fast and unambiguous detection of solid forms of these organic acids (formic, acetic, valeric, hexanoic, heptanoic, isophthalic, ascorbic and mellitic) under field conditions. This demonstrates the possibility to use a miniaturized Raman spectrometer as a key instrument for investigating the presence of organic compounds and biomolecules under low temperature conditions. These results are important for future missions focusing not only on Mars, where Raman spectroscopy will be a key non-destructive analytical tool for the in situ identification of organic compounds relevant to life detection on planetary surfaces or near sub-surfaces. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Krill for Human Consumption: Nutritional Value and Potential Health Benefits

NUTRITION REVIEWS, Issue 2 2007
Janet C. Tou PhD
The marine crustacean krill (order Euphausiacea) has not been a traditional food in the human diet. Public acceptance of krill for human consumption will depend partly on its nutritive value. The aim of this article is to assess the nutritive value and potential health benefits of krill, an abundant food source with high nutritional value and a variety of compounds relevant to human health. Krill is a rich source of high-quality protein, with the advantage over other animal proteins of being low in fat and a rich source of omega-3 fatty acids. Antioxidant levels in krill are higher than in fish, suggesting benefits against oxidative damage. Finally, the waste generated by the processing of krill into edible products can be developed into value-added products. [source]