Search results for " SPECT"
showing 10 items of 11464 documents
19F NMR as a versatile tool to study membrane protein structure and dynamics.
2019
Abstract To elucidate the structures and dynamics of membrane proteins, highly advanced biophysical methods have been developed that often require significant resources, both for sample preparation and experimental analyses. For very complex systems, such as membrane transporters, ion channels or G-protein coupled receptors (GPCRs), the incorporation of a single reporter at a select site can significantly simplify the observables and the measurement/analysis requirements. Here we present examples using 19F nuclear magnetic resonance (NMR) spectroscopy as a powerful, yet relatively straightforward tool to study (membrane) protein structure, dynamics and ligand interactions. We summarize meth…
Anti-Cancer Activity of Resveratrol and Derivatives Produced by Grapevine Cell Suspensions in a 14 L Stirred Bioreactor
2017
International audience; In the present study, resveratrol and various oligomeric derivatives were obtained from a 14 L bioreactor culture of elicited grapevine cell suspensions (Vitis labrusca L.). The crude ethyl acetate stilbene extract obtained from the culture medium was fractionated by centrifugal partition chromatography (CPC) using a gradient elution method and the major stilbenes contained in the fractions were subsequently identified by using a (13)C-NMR-based dereplication procedure and further 2D NMR analyses including HSQC, HMBC, and COSY. Beside δ-viniferin (2), leachianol F (4) and G (4'), four stilbenes (resveratrol (1), ε-viniferin (5), pallidol (3) and a newly characterized…
Cytotoxicity of Labruscol, a New Resveratrol Dimer Produced by Grapevine Cell Suspensions, on Human Skin Melanoma Cancer Cell Line HT-144
2017
IF 2.861; International audience; A new resveratrol dimer (1) called labruscol, has been purified by centrifugal partition chromatography of a crude ethyl acetate stilbene extract obtained from elicited grapevine cell suspensions of Vitis labrusca L. cultured in a 14-liter stirred bioreactor. One dimensional (1D) and two dimensional (2D) nuclear magnetic resonance (NMR) analyses including ¹H, 13C, heteronuclear single-quantum correlation (HSQC), heteronuclear multiple bond correlation (HMBC), and correlation spectroscopy (COSY) as well as high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS) were used to characterize this compound and to unambiguously identify it as a new st…
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 …
Broad neurodevelopmental features and cortical anomalies associated with a novel de novo KMT2A variant in Wiedemann-Steiner syndrome.
2021
Abstract Wiedemann-Steiner syndrome (WDSTS) is a rare genetic disorder including developmental delay/intellectual disability (DD/ID), hypertrichosis cubiti, short stature, and distinctive facial features, caused by mutation in KMT2A gene, which encodes a histone methyltransferase (H3K4) that regulates chromatin-mediated transcription. Different neurodevelopmental phenotypes have been described within the WDSTS spectrum, including a peculiar Autism Spectrum Disorder (ASDs) subtype in some affected individuals. Here, we report a 9-year-old Caucasian male found by next-generation panel sequencing to carry a novel heterozygous de novo KMT2A frameshift variant (NM_001197104.2:c.4433delG; p. Arg1…
Noninvasive optical diagnostics of enhanced green fluorescent protein expression in skeletal muscle for comparison of electroporation and sonoporatio…
2015
We highlight the options available for noninvasive optical diagnostics of reporter gene expression in mouse tibialis cranialis muscle. An in vivo multispectral imaging technique combined with fluorescence spectroscopy point measurements has been used for the transcutaneous detection of enhanced green fluorescent protein (EGFP) expression, providing information on location and duration of EGFP expression and allowing quantification of EGFP expression levels. For EGFP coding plasmid (pEGFP-Nuc Vector, 10 μg/50 ml 10 μg/50 ml ) transfection, we used electroporation or ultrasound enhanced microbubble cavitation [sonoporation (SP)]. The transcutaneous EGFP fluorescence in live mice was monit…
Vitamin D Status and the Relationship with Bone Fragility Fractures in HIV-Infected Patients: A Case Control Study
2018
HIV-infected patients show high risk of fracture. The aims of our study were to determine the prevalence of vertebral fractures (VFs) and their associations with vitamin D in HIV patients. 100 patients with HIV infection and 100 healthy age-and sex-matched controls were studied. Bone mineral density was measured by quantitative ultrasound at the non-dominant heel. Serum osteocalcin and C-terminal telopeptide of collagen type 1 served as bone turnover markers. Bone ultrasound measurements were significantly lower in patients compared with controls (Stiffness Index (SI): 80.58 ± 19.95% vs. 93.80 ± 7.10%, respectively, p < 0.001). VFs were found in 16 patients and in 2 controls. HIV patie…