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151.
Sheila M. Innis 《Critical reviews in food science and nutrition》2016,56(12):1952-1959
Palmitic acid (16:0) is a saturated fatty acid present in the diet and synthesized endogenously. Although often considered to have adverse effects on chronic disease in adults, 16:0 is an essential component of membrane, secretory, and transport lipids, with crucial roles in protein palmitoylation and signal molecules. At birth, the term infant is 13–15% body fat, with 45–50% 16:0, much of which is derived from endogenous synthesis in the fetus. After birth, the infant accumulates adipose tissue at high rates, reaching 25% body weight as fat by 4–5 months age. Over this time, human milk provides 10% dietary energy as 16:0, but in unusual triglycerides with 16:0 on the glycerol center carbon. This paper reviews the synthesis and oxidation of 16:0 and possible reasons why the infant is endowed with large amounts of fat and 16:0. The marked deviations in tissues with displacement of 16:0 that can occur in infants fed vegetable oil formulas is introduced. Assuming fetal fatty acid synthesis and the unusual delivery of 16:0 in human milk evolved to afford survival advantage to the neonate, it is timely to question if 16:0 is an essential component of tissue lipids whereby both deficiency and excess are detrimental. 相似文献
152.
Teriflunomide Inhibits JCPyV Infection and Spread in Glial Cells and Choroid Plexus Epithelial Cells
Bethany A. OHara Gretchen V. Gee Sheila A. Haley Jenna Morris-Love Charlotte Nyblade Chris Nieves Barbara A. Hanson Xin Dang Timothy J. Turner Jeffrey M. Chavin Alex Lublin Igor J. Koralnik Walter J. Atwood 《International journal of molecular sciences》2021,22(18)
Several classes of immunomodulators are used for treating relapsing-remitting multiple sclerosis (RRMS). Most of these disease-modifying therapies, except teriflunomide, carry the risk of progressive multifocal leukoencephalopathy (PML), a severely debilitating, often fatal virus-induced demyelinating disease. Because teriflunomide has been shown to have antiviral activity against DNA viruses, we investigated whether treatment of cells with teriflunomide inhibits infection and spread of JC polyomavirus (JCPyV), the causative agent of PML. Treatment of choroid plexus epithelial cells and astrocytes with teriflunomide reduced JCPyV infection and spread. We also used droplet digital PCR to quantify JCPyV DNA associated with extracellular vesicles isolated from RRMS patients. We detected JCPyV DNA in all patients with confirmed PML diagnosis (n = 2), and in six natalizumab-treated (n = 12), two teriflunomide-treated (n = 7), and two nonimmunomodulated (n = 2) patients. Of the 21 patients, 12 (57%) had detectable JCPyV in either plasma or serum. CSF was uniformly negative for JCPyV. Isolation of extracellular vesicles did not increase the level of detection of JCPyV DNA versus bulk unprocessed biofluid. Overall, our study demonstrated an effect of teriflunomide inhibiting JCPyV infection and spread in glial and choroid plexus epithelial cells. Larger studies using patient samples are needed to correlate these in vitro findings with patient data. 相似文献
153.
Proteomic technologies are important because they link genes, proteins and disease. The identification of proteins and peptides has been revolutionized in the last decade by the use of mass spectrometry. This method is highly sensitive and much faster than the chemical reactions used previously because it can fragment peptides in seconds rather than in hours or days. Proteins are digested with an enzyme, usually trypsin, and the resulting peptides are fragmented in a tandem mass spectrometer (MS/MS). The masses of the fragment ions formed in the MS/MS can be used to identify the sequence of amino acids in the peptides. However, a number of different factors have been found to influence the amount of the various types of fragment ion formed. In this article, we review these factors and their interrelation together with the statistical methods used to discover them. Information on the number of fragment ions formed is at present underused in peptide identification algorithms, and fully utilizing this information could improve current algorithms. 相似文献
154.
Dilmore RM Allen DE Jones JR Hedges SW Soong Y 《Environmental science & technology》2008,42(8):2760-2766
Experiments were conducted to determine the solubility of CO2 in a natural brine solution of the Oriskany formation under elevated temperature and pressure conditions. These data were collected at temperatures of 22 and 75 degrees C and pressures between 100 and 450 bar. Experimentally determined data were compared with CO2 solubility predictions using a model developed by Duan and Sun (Chem. Geol. 2003, 193, 257-271). Model results compare well with Oriskany brine CO2 solubility data collected experimentally, suggesting that the Duan and Sun model is a reliable tool for estimating solution CO2 capacity in high salinity aquifers in the temperature and pressure range evaluated. The capacity for the Oriskany formation to sequester dissolved CO2 was calculated using results of the solubility models, estimation of the density of CO2 saturated brine, and available geographic information system (GIS) information on the formation depth and thickness. Results indicate that the Oriskany formation can hold approximately 0.36 gigatonnes of dissolved CO2 if the full basin is considered. When only the region where supercritical CO2 can exist (temperatures greaterthan 31 degrees C and pressures greaterthan 74 bar) is considered, the capacity of the Oriskany formation to sequester dissolved CO2 is 0.31 gigatonnes. The capacity estimate considering the potential to sequester free-phase supercritical CO2 if brine were displaced from formation pore space is 8.8 gigatonnes in the Oriskany formation. 相似文献
155.
Improvement of existing properties and creation of new material properties are the most important reasons for increasing industrial uses of cotton fabrics. In this research work, carboxylated single-walled carbon nanotubes (CSWCNT) were stabilized by different methods on a cotton fabric surface, using citric acid (CA) as a cross-linking agent and sodium hypophosphite (SHP) as a catalyst. A scanning electron microscope, electrical resistivity equipment, reflective spectrophotometer has been applied to investigate the influence of carboxylated single-walled carbon nanotube on the performance of the cotton fabrics. Also the flammability of cotton fabric modified by CSWCNT, CA, and SHP was evaluated by measuring the percentage of char yield. The test results were compared and discussed. 相似文献
156.
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159.
Raquel Sanabria-de la Torre Cristina García-Fontana Sheila Gonzlez-Salvatierra Francisco Andújar-Vera Luis Martínez-Heredia Beatriz García-Fontana Manuel Muoz-Torres 《International journal of molecular sciences》2022,23(13)
Vascular complications are the leading cause of morbidity and mortality among patients with type 2 diabetes mellitus (T2DM). These vascular abnormalities result in a chronic hyperglycemic state, which influences many signaling molecular pathways that initially lead to increased oxidative stress, increased inflammation, and endothelial dysfunction, leading to both microvascular and macrovascular complications. Endothelial dysfunction represents the initial stage in both types of vascular complications; it represents “mandatory damage” in the development of microvascular complications and only “introductory damage” in the development of macrovascular complications. Increasing scientific evidence has revealed an important role of the Wnt pathway in the pathophysiology of the vascular wall. It is well known that the Wnt pathway is altered in patients with T2DM. This review aims to be an update of the current literature related to the Wnt pathway molecules that are altered in patients with T2DM, which may also be the cause of damage to the vasculature. Both microvascular complications (retinopathy, nephropathy, and neuropathy) and macrovascular complications (coronary artery disease, cerebrovascular disease, and peripheral arterial disease) are analyzed. This review aims to concisely concentrate all the evidence to facilitate the view on the vascular involvement of the Wnt pathway and its components by highlighting the importance of exploring possible therapeutic strategy for patients with T2DM who develop vascular pathologies. 相似文献
160.
Arnau Navins-Ferrer Sheila Ruiz-Nogales Rafael Navarro Esther Pomares 《International journal of molecular sciences》2022,23(13)
Best Vitelliform Macular dystrophy (BVMD) is the most prevalent of the distinctive retinal dystrophies caused by mutations in the BEST1 gene. This gene, which encodes for a homopentameric calcium-activated ion channel, is crucial for the homeostasis and function of the retinal pigment epithelia (RPE), the cell type responsible for recycling the visual pigments generated by photoreceptor cells. In BVMD patients, mutations in this gene induce functional problems in the RPE cell layer with an accumulation of lipofucsin that evolves into cell death and loss of sight. In this work, we employ iPSC-RPE cells derived from a patient with the p.Pro77Ser dominant mutation to determine the correlation between this variant and the ocular phenotype. To this purpose, gene and protein expression and localization are evaluated in iPSC-RPE cells along with functional assays like phagocytosis and anion channel activity. Our cell model shows no differences in gene expression, protein expression/localization, or phagocytosis capacity, but presents an increased chloride entrance, indicating that the p.Pro77Ser variant might be a gain-of-function mutation. We hypothesize that this variant disturbs the neck region of the BEST1 channel, affecting channel function but maintaining cell homeostasis in the short term. This data shed new light on the different phenotypes of dominant mutations in BEST1, and emphasize the importance of understanding its molecular mechanisms. Furthermore, the data widen the knowledge of this pathology and open the door for a better diagnosis and prognosis of the disease. 相似文献