Search results for "MASS SPECTROMETRY"
showing 10 items of 2544 documents
The Complete Structure of the Core Oligosaccharide from Edwardsiella tarda EIB 202 Lipopolysaccharide
2017
The chemical structure and genomics of the lipopolysaccharide (LPS) core oligosaccharide of pathogenic Edwardsiella tarda strain EIB 202 were studied for the first time. The complete gene assignment for all LPS core biosynthesis gene functions was acquired. The complete structure of core oligosaccharide was investigated by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, electrospray ionization mass spectrometry MSn, and matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry. The following structure of the undecasaccharide was established: The heterogeneous appearance of the core oligosaccharide structure was due to the partial lack of β-d-Galp and the replace…
7,8-hydroxy-2′-deoxyguanosine/2′-deoxiguanosine ratio determined in hydrolysates of brain DNA by ultrachromatrography coupled to tandem mass spectrom…
2017
7,8-hydroxy-2'-deoxyguanosine (8-OHdG) is an abundant DNA lesion formed by oxidation of the nucleoside 2'-deoxyguanosine (2-dG) and one of the most studied and accepted oxidative stress biomarkers. 8-OHdG has a strong carcinogenic potential, and prolonged oxidative stress heightens pathological conditions and especially cancer risk. Our aim was to develop, validate and apply a reliable method to assess DNA oxidation in genomic cellular DNA of sensible target organs such as brain. A procedure to isolate and digest the DNA of brain tissue properly for further detection of 8-OHdG and 2-dG by Ultra Performance Liquid Chromatography tandem Mass Spectrometry (UPLC-MS/MS) was optimized. The UPLC-M…
A critical evaluation of Amicon Ultra centrifugal filters for separating proteins, drugs and nanoparticles in biosamples
2015
Amicon(®) Ultra centrifugal filters were critically evaluated for various sample preparations, namely (a) proteome fractionation, (b) sample cleanup prior to liquid chromatography mass spectrometry (LC-MS) measurement of small molecules in cell lysate, and (c) separating drug-loaded nanoparticles and released drugs for accurate release profiling in biological samples. (a) Filters of supposedly differing molar mass (MM) selectivity (10, 30, 50 and 100K) were combined to attempt fractionation of samples of various complexity and concentration. However, the products had surprisingly similar MM retentate/filtrate profiles, and the filters were unsuited for proteome fractionation. (b) Centrifuga…
A Stress-Resistant Lipidomic Signature Confers Extreme Longevity to Humans.
2015
Plasma lipidomic profile is species specific and an optimized feature associated with animal longevity. In the present work, the use of mass spectrometry technologies allowed us to determine the plasma lipidomic profile and the fatty acid pattern of healthy humans with exceptional longevity. Here, we show that it is possible to define a lipidomic signature only using 20 lipid species to discriminate adult, aged and centenarian subjects obtaining an almost perfect accuracy (90%-100%). Furthermore, we propose specific lipid species belonging to ceramides, widely involved in cell-stress response, as biomarkers of extreme human longevity. In addition, we also show that extreme longevity present…
Exceptional human longevity is associated with a specific plasma phenotype of ether lipids
2019
A lipid profile resistant to oxidative damage is an inherent trait associated with animal lifespan. However, there is a lack of lipidomic studies on human longevity. Here we use mass spectrometry based technologies to detect and quantify 137 ether lipids to define a phenotype of healthy humans with exceptional lifespan. Ether lipids were chosen because of their antioxidant properties and ability to modulate oxidative stress. Our results demonstrate that a specific ether lipid signature can be obtained to define the centenarian state. This profile comprises higher level of alkyl forms derived from phosphatidylcholine with shorter number of carbon atoms and double bonds; and decreased content…
Substantial deficiency of free sialic acid in muscles of patients with GNE myopathy and in a mouse model
2017
GNE myopathy (GNEM), also known as hereditary inclusion body myopathy (HIBM), is a late- onset, progressive myopathy caused by mutations in the GNE gene encoding the enzyme responsible for the first regulated step in the biosynthesis of sialic acid (SA). The disease is characterized by distal muscle weakness in both the lower and upper extremities, with the quadriceps muscle relatively spared until the late stages of disease. To explore the role of SA synthesis in the disease, we conducted a comprehensive and systematic analysis of both free and total SA levels in a large cohort of GNEM patients and a mouse model. A sensitive LC/MS/MS assay was developed to quantify SA in serum and muscle h…
Mouse tissue distribution and persistence of the food-born fusariotoxins Enniatin B and Beauvericin
2016
The fusariotoxins Enniatin B (Enn B) and Beauvericin (Bea) have recently aroused interest as food contaminants and as potential anticancer drugs. However, limited data are available about their toxic profile. Aim of this study was to investigate their pharmacological behavior in vivo and their persistence in mice. Therefore, liquid chromatography tandem mass spectrometry (LC-MS/MS) was used to analyze the distribution of Enn B and Bea in selected tissue samples and biological fluids originating from mice treated intraperitoneally with these cyclohexadepsipeptides. Overall, no toxicological signs during life time or pathological changes were observed. Moreover, both fusariotoxins were found …
Targeting brain and peripheral plasticity of the lipidome in acute kainic acid-induced epileptic seizures in mice via quantitative mass spectrometry.
2017
Epilepsy is a highly common chronic neurological disorder, manifested in many different types, affecting ~1% of the worldwide human population. The molecular mechanisms of epileptogenesis have not yet been clarified, and pharmacoresistance exhibited by 30-40% of epilepsy patients remains a major obstacle in medical care. Growing evidence indicates a role of lipid signalling pathways in epileptogenesis, thus lipid signals emerge as potential biomarkers for the onset and evolving course of the epileptic disorder, as well as potential therapeutic agents and targets. For this purpose, we applied a lipidomic strategy to unravel lipid alterations in brain regions, periphery tissues and plasma tha…
Oligodendrocytes support axonal transport and maintenance via exosome secretion
2020
Neurons extend long axons that require maintenance and are susceptible to degeneration. Long-term integrity of axons depends on intrinsic mechanisms including axonal transport and extrinsic support from adjacent glial cells. The mechanisms of support provided by myelinating oligodendrocytes to underlying axons are only partly understood. Oligodendrocytes release extracellular vesicles (EVs) with properties of exosomes, which upon delivery to neurons improve neuronal viability in vitro. Here, we show that oligodendroglial exosome secretion is impaired in 2 mouse mutants exhibiting secondary axonal degeneration due to oligodendrocyte-specific gene defects. Wild-type oligodendroglial exosomes …
Autoantibodies Profile in Matching CSF and Serum from AD and aMCI patients: Potential Pathogenic Role and Link to Oxidative Damage.
2015
Abstract Alzheimer disease (AD) is the most common form of dementia among the elderly and is characterized by progressive loss of memory and cognition. Amyloid-s-peptide (As) forms senile plaques, which, together with hyperphosphorylated tau-based neurofibrillary tangles, are the hallmarks of AD neuropathology. Evidence support the involvement of immune system in AD progression and current concepts regarding its pathogenesis include the participation of inflammatory and autoimmune components in the neurodegenerative process. Pathologically, immune system components have been detected in the brain, cerebrospinal fluid (CSF) and in serum of AD subjects and their trend of variation correlates …