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https://www.readbyqxmd.com/read/28650855/intermittent-vs-continuous-enteral-feeding-to-prevent-catabolism-in-acutely-ill-adult-and-pediatric-patients
#1
Filippo G Di Girolamo, Roberta Situlin, Nicola Fiotti, Gianni Biolo
PURPOSE OF REVIEW: In clinical management of acutely ill adults and children, continuous enteral feeding (CEF), being considered the most tolerable approach, in comparison to other temporal patterns of nutrient administration (i.e. intermittent, cyclic and bolus), is the most frequently applied method. However, uncertainties remain about the most efficient approach to counteract protein catabolism. RECENT FINDINGS: In critically ill adults, protein loss is mainly driven by increased protein breakdown whereas, in pediatric patients, acute illness is mainly characterized by blunted regulation of protein synthesis and stunted growth...
June 24, 2017: Current Opinion in Clinical Nutrition and Metabolic Care
https://www.readbyqxmd.com/read/28650854/recent-developments-in-deuterium-oxide-tracer-approaches-to-measure-rates-of-substrate-turnover-implications-for-protein-lipid-and-nucleic-acid-research
#2
Matthew S Brook, Daniel J Wilkinson, Philip J Atherton, Ken Smith
PURPOSE OF REVIEW: Methods that inform on dynamic metabolism that can be applied to clinical populations to understand disease progression and responses to therapeutic interventions are of great importance. This review perspective will highlight recent advances, development, and applications of the multivalent stable isotope tracer deuterium oxide (D2O) to the study of substrate metabolism with particular reference to protein, lipids, and nucleic acids, and how these methods can be readily applied within clinical and pharmaceutical research...
June 24, 2017: Current Opinion in Clinical Nutrition and Metabolic Care
https://www.readbyqxmd.com/read/28650827/neural-decomposition-of-time-series-data-for-effective-generalization
#3
Luke B Godfrey, Michael S Gashler
We present a neural network technique for the analysis and extrapolation of time-series data called neural decomposition (ND). Units with a sinusoidal activation function are used to perform a Fourier-like decomposition of training samples into a sum of sinusoids, augmented by units with nonperiodic activation functions to capture linear trends and other nonperiodic components. We show how careful weight initialization can be combined with regularization to form a simple model that generalizes well. Our method generalizes effectively on the Mackey-Glass series, a data set of unemployment rates as reported by the U...
June 22, 2017: IEEE Transactions on Neural Networks and Learning Systems
https://www.readbyqxmd.com/read/28650041/competition-between-the-h-and-d-atom-transfer-channels-in-the-h2o-hd-reaction-reduced-dimensional-quantum-and-quasi-classical-studies
#4
Hongwei Song, Anyang Li, Minghui Yang, Hua Guo
The ion-molecule reaction between a water cation and a hydrogen molecule has recently attracted considerable interest due to its importance in astrochemistry. In this work, the intramolecular isotope effect of the H2O(+) + HD reaction is investigated using a seven-dimensional initial state-selected time-dependent wave packet approach as well as a full-dimensional quasi-classical trajectory method on a full-dimensional ab initio global potential energy surface. The calculated branching ratios for the formation of H3O(+) and H2DO(+)via H- and D-transfer agree reasonably well with the experimental values...
June 26, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28649867/study-of-isotopes-of-carbon-thorium-and-uranium-in-travertine-and-thermal-spring-samples-implications-for-effects-of-changes-in-geochemical-environment-and-processes
#5
Alexander I Malov
Data on modern radiocarbon activity in the old travertine formations of the Pymvashor hydrothermal system were used, in combination with (230)Th/U dating of the travertine, to estimate the (14)C contents of the total dissolved inorganic carbon in the ancient thermal water at the time of precipitation of the travertine ((14)Ccalc). With the known values of (14)Ccalc and average age of the thermal water, and under the assumption that the residence time of the water in aquifer was constant over the last 13.9 ± 1...
June 26, 2017: Isotopes in Environmental and Health Studies
https://www.readbyqxmd.com/read/28649835/transition-metal-free-c-h-hydroxylation-of-carbonyl-compounds
#6
Moreshwar B Chaudhari, Yogesh Sutar, Shreyas Malpathak, Anirban Hazra, Boopathy Gnanaprakasam
Transition metal and reductant free α-C(sp3)-H hydroxylation of carbonyl compounds are reported. This method is promoted by commercially available inexpensive KO-t-Bu and atmospheric air as an oxidant at room temperature. This unified strategy is also very facile for hydroxylation of various carbonyl compound derivatives to obtain quaternary hydroxyl compounds in excellent yield. A preliminary mechanistic investigation, supported by isotope labeling and computational studies, suggests the formation of a peroxide bond and its cleavage by in situ generated enolate...
June 26, 2017: Organic Letters
https://www.readbyqxmd.com/read/28649716/mechanism-of-microwave-assisted-pyrolysis-of-glucose-to-furfural-revealed-by-isotopic-tracer-and-quantum-chemical-calculations
#7
Liwei Bao, Lei Shi, Hu Luo, Lingzhao Kong, Shenggang Li, Wei Wei, Yuhan Sun
Glucose labelled with 13C or 18O was used to investigate the mechanism during its conversion into furfural by microwave-assisted pyrolysis. The isotopic content and location in furfural were determined from GC/MS and 13C NMR measurements and data analysis. Our results suggest that the carbon skeleton in furfural is mainly derived from the C-1 to C-5 of glucose. The C of the aldehyde group and the O of the furan ring in furfural are primarily originated from the C-1 and O-5 of glucose, respectively. For the first time, the source of the O of the furan ring in furfural was elucidated directly by experiments, which is consistent with predictions from recent quantum chemical calculations...
June 25, 2017: ChemSusChem
https://www.readbyqxmd.com/read/28649615/imaging-parkinson-s-disease-below-the-neck
#8
Per Borghammer, Karoline Knudsen, Tatyana D Fedorova, David J Brooks
Parkinson's disease is a systemic disorder with widespread and early α-synuclein pathology in the autonomic and enteric nervous systems, which is present throughout the gastrointestinal canal prior to diagnosis. Gastrointestinal and genitourinary autonomic symptoms often predate clinical diagnosis by several years. It has been hypothesized that progressive α-synuclein aggregation is initiated in hyperbranched, non-myelinated neuron terminals, and may subsequently spread via retrograde axonal transport. This would explain why autonomic nerves are so prone to formation of α-synuclein pathology...
2017: NPJ Parkinson's Disease
https://www.readbyqxmd.com/read/28649594/specific-macronutrients-exert-unique-influences-on-the-adipose-liver-axis-to-promote-hepatic-steatosis-in-mice
#9
Caroline C Duwaerts, Amin M Amin, Kevin Siao, Chris Her, Mark Fitch, Carine Beysen, Scott M Turner, Amanda Goodsell, Jody L Baron, James P Grenert, Soo-Jin Cho, Jacquelyn J Maher
BACKGROUND & AIMS: The factors that distinguish metabolically healthy obesity from metabolically unhealthy obesity are not well understood. Diet has been implicated as a determinant of the unhealthy obesity phenotype, but which aspects of the diet induce dysmetabolism are unknown. The goal of this study was to investigate whether specific macronutrients or macronutrient combinations provoke dysmetabolism in the context of isocaloric, high-energy diets. METHODS: Mice were fed 4 high-energy diets identical in calorie and nutrient content but different in nutrient composition for 3 weeks to 6 months...
September 2017: Cellular and Molecular Gastroenterology and Hepatology
https://www.readbyqxmd.com/read/28649330/dual-tracer-based-isotope-turnover-rates-in-a-highly-invasive-mysid-limnomysis-benedeni-from-lake-constance
#10
Elizabeth Yohannes, Karl-Otto Rothhaupt
Understanding the ecological patterns of invasive species and their habitats require an understanding of the species' foraging ecology. Stable carbon (δ(13)C) and nitrogen (δ(15)N) isotope values provide useful information into the study of animal ecology and evolution, since the isotope ratios of consumers reflect consumer's dietary patterns. Nevertheless, the lack of species- and element-specific laboratory-derived turnover rates could limit their application. Using a laboratory-based dual stable isotope tracer approach (Na(15) NO 3 and NaH(13) CO 3), we evaluated the δ(15)N and δ(13)C isotope turnover rates in full-grown adult invasive Limnomysis benedeni from Lake Constance...
June 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28649019/a-preliminary-study-for-the-production-of-high-specific-activity-radionuclides-for-nuclear-medicine-obtained-with-the-isotope-separation-on-line-technique
#11
F Borgna, M Ballan, S Corradetti, E Vettorato, A Monetti, M Rossignoli, M Manzolaro, D Scarpa, U Mazzi, N Realdon, A Andrighetto
Radiopharmaceuticals represent a fundamental tool for nuclear medicine procedures, both for diagnostic and therapeutic purposes. The present work aims to explore the Isotope Separation On-Line (ISOL) technique for the production of carrier-free radionuclides for nuclear medicine at SPES, a nuclear physics facility under construction at INFN-LNL. Stable ion beams of strontium, yttrium and iodine were produced using the SPES test bench (Front-End) to simulate the production of (89)Sr, (90)Y, (125)I and (131)I and collected with good efficiency on suitable targets...
June 17, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/28649010/mussels-do-not-directly-assimilate-fish-farm-wastes-shifting-the-rationale-of-integrated-multi-trophic-aquaculture-to-a-broader-scale
#12
Carlos Sanz-Lazaro, Pablo Sanchez-Jerez
Pollution is one of the most significant issues that is currently impeding the development of fish farming. Integrated multi-trophic aquaculture (IMTA) has the potential to reduce the accumulation of organic wastes in the environment by using taxa of lower trophic levels such as filter feeders. However, the capacity of filter feeders to assimilate significant quantities of fish farm wastes has not yet been fully tested in situ. We analyzed the stable isotopes δ(13)C and δ(15)N in mussels from six fish farms and from six other areas that were not influenced by fish farming, at two water strata (surface and mid-water) across a marked gradient of eutrophication along more than 900 km of coastline in the Western Mediterranean...
June 22, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28648083/temporal-signal-pattern-recognition-in-mass-spectrometry-a-method-for-rapid-identification-and-accurate-quantification-of-biomarkers-for-inborn-errors-of-metabolism-with-quality-assurance
#13
Alicia DiBattista, Nathan McIntosh, Monica Lamoureux, Osama Al-Dirbashi, Pranesh Chakraborty, Philip Britz-McKibbin
Mass spectrometry (MS)-based metabolomic initiatives that use conventional separation techniques are limited by low sample throughput and complicated data processing that contribute to false discoveries. Herein, we introduce a new strategy for unambiguous identification and accurate quantification of biomarkers for inborn errors of metabolism (IEM) from dried blood spots (DBS) with quality assurance. A multiplexed separation platform based on multisegment injection-capillary electrophoresis-mass spectrometry (MSI-CE-MS) was developed to provide comparable sample throughput to flow injection analysis-tandem MS (FIA-MS/MS), but with greater selectivity as required for confirmatory testing and discovery-based metabolite profiling of volume-restricted biospecimens...
June 25, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28648049/analysis-of-liquid-chromatography-mass-spectrometry-data-with-an-elastic-net-multivariate-curve-resolution-strategy-for-sparse-spectral-recovery
#14
Daniel Wesley Cook, Sarah C Rutan
Analysis of liquid chromatography-mass spectrometry (LC-MS) data requires the differentiation between a small number of relevant chemical signals and a larger amount of noise. This is often done based, at least partially, on a threshold which assumes that low intensity m/z signals arise from the noise. This eliminates low intensity fragments, isotopes, and adducts and may exclude relevant low-intensity compounds all together. This work describes the use of multivariate curve resolution-alternating least squares with an additional sparse regression step using elastic net (MCR-ENALS) to distinguish relevant m/z signals without the use of a harsh thresholding step, thus allowing for discovery of low intensity m/z signals corresponding to the analytes...
June 24, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28647758/a-meta-analysis-of-quantitative-trait-loci-for-abiotic-and-biotic-stress-resistance-in-tetraploid-cotton
#15
Abdelraheem Abdelraheem, Feng Liu, Mingzhou Song, Jinfa F Zhang
The number and location of mapped quantitative trait loci (QTL) depend on genetic populations and testing environments. The identification of consistent QTL across genetic backgrounds and environments is a pre-requisite to marker-assisted selection. This study analyzed a total of 661 abiotic and biotic stress resistance QTL based on our previous work and other publications using the meta-analysis software Biomercator. It identified chromosomal regions containing QTL clusters for different resistance traits and hotspots for a particular resistance trait in cotton from 98 QTL for drought tolerance under greenhouse (DT) and 150 QTL in field conditions (FDT), 80 QTL for salt tolerance in the greenhouse conditions (ST), 201 QTL for resistance to Verticillium wilt (VW, Verticillium dahliae), 47 QTL for resistance to Fusarium wilt (FW, Fusarium oxysporum f...
June 24, 2017: Molecular Genetics and Genomics: MGG
https://www.readbyqxmd.com/read/28647528/the-linkage-between-nutrient-supply-intracellular-enzyme-abundances-and-bacterial-growth-new-evidences-from-the-central-carbon-metabolism-of-corynebacterium-glutamicum
#16
Stephan Noack, Raphael Voges, Jochem Gätgens, Wolfgang Wiechert
Corynebacterium glutamicum serves as important production host for small molecular compounds that are derived from precursor molecules of the central carbon metabolism. It is therefore a well-studied model organism of industrial biotechnology. However, a deeper understanding of the regulatory principles underlying the synthesis of central metabolic enzymes under different environmental conditions as well as its impact on cell growth is still missing. We studied enzyme abundances in C. glutamicum in response to growth on: i) one limiting carbon source by sampling chemostat and fed-batch cultivations and ii) changing carbon sources provided in excess by sampling batch cultivations...
June 21, 2017: Journal of Biotechnology
https://www.readbyqxmd.com/read/28647121/dna-based-stable-isotope-probing-identifies-formate-metabolizing-methanogenic-archaea-in-paddy-soil
#17
Jiangbing Xu, Zhongjun Jia, Xiangui Lin, Youzhi Feng
Paddy methane (CH4) production is biologically dominated by methanogenic archaea that metabolize a variety of organic and/or inorganic carbon sources. Though formate is easily dissimilated into H2/CO2, formate-metabolizing methanogenic archaea are distinct from CO2-utilizing methanogen taxa. The identity of formate-metabolizing methanogenic archaea in paddy soil remains elusive. In this investigation, molecular approaches based on stable isotope probing (SIP) technique were conducted to identify the formate-metabolizing methanogenic archaea in paddy soil...
September 2017: Microbiological Research
https://www.readbyqxmd.com/read/28646737/pollution-characteristics-and-source-identification-of-trace-metals-in-riparian-soils-of-miyun-reservoir-china
#18
Lanfang Han, Bo Gao, Jin Lu, Yang Zhou, Dongyu Xu, Li Gao, Ke Sun
The South-to-North Water Diversion Project, one of China's largest water diversion projects, has aroused widespread concerns about its potential ecological impacts, especially the potential release of trace metals from shoreline soils into Miyun Reservoir (MYR). Here, riparian soil samples from three elevations and four types of land use were collected. Soil particle size distributions, contents and chemical fractionations of trace metals and lead (Pb) isotopic compositions were analyzed. Results showed that soil texture was basically similar in four types of land use, being mainly composed of sand, with minor portions of clay and silt, while recreational land contained more abundant chromium (Cr), copper (Cu), zinc (Zn) and cadmium (Cd), suggesting a possible anthropogenic source for this soil pollution...
June 21, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/28646418/in-vivo-nmr-as-a-tool-for-probing-molecular-structure-and-dynamics-in-intact-chlamydomonas-reinhardtii-cells
#19
Fatemeh Azadi-Chegeni, Christo Schiphorst, Anjali Pandit
We report the application of NMR dynamic spectral editing for probing the structure and dynamics of molecular constituents in fresh, intact cells and in freshly prepared thylakoid membranes of Chlamydomonas reinhardtii (Cr.) green algae. For isotope labeling, wild-type Cr. cells were grown on (13)C acetate-enriched minimal medium. 1D (13)C J-coupling based and dipolar-based MAS NMR spectra were applied to distinguish (13)C resonances of different molecular components. 1D spectra were recorded over a physiological temperature range, and whole-cell spectra were compared to those taken from thylakoid membranes, evaluating their composition and dynamics...
June 23, 2017: Photosynthesis Research
https://www.readbyqxmd.com/read/28646176/enhanced-atomic-desorption-of-209-and-210-francium-from-organic-coating
#20
Steinn Agustsson, Giovanni Bianchi, Roberto Calabrese, Lorenzo Corradi, Antonio Dainelli, Alen Khanbekyan, Carmela Marinelli, Emilio Mariotti, Luca Marmugi, Leonardo Ricci, Leonardo Stiaccini, Luca Tomassetti, Andrea Vanella
Controlled atomic desorption from organic Poly-DiMethylSiloxane coating is demonstrated for improving the loading efficiency of (209,210)Fr magneto-optical traps. A three times increase in the cold atoms population is obtained with contact-less pulsed light-induced desorption, applied to different isotopes, either bosonic or fermionic, of Francium. A six times increase of (210)Fr population is obtained with a desorption mechanism based on direct charge transfer from a triboelectric probe to the adatom-organic coating complex...
June 23, 2017: Scientific Reports
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