A Robust Protocol for Extracting Aqueous Metabolites of High Lipid Sera

Background: With the increasing focus of metabolomic methods on obesityrelated diseases, it is important to consider how sample handling may need to be adapted for the high compositions of lipids that can occur in such subjects. Introduction: High-lipid (cloudy, milky appearances; a.k.a. lipemic) biofluids are common in very high BMI subjects. Organic extractions of biofluids are useful for removing protein backgrounds, inactivating capsid viruses, and yielding relatively stable samples with excellent spectroscopic characteristics. This work considered how acetonitrile extractions, which are widely used, perform on lipemic sera. Results: In this technical note, we report the observation and remediation of a liquid-liquid phase separation in acetonitrile extractions of many lipemic sera. This unexpected behavior can be challenging to identify, especially if working with small volumes. The liquid-liquid separation shows a high miscibility of proteins in both liquid phases that impairs NMR data quality. We also report a simple temperature-based adaption of the acetonitrile extraction procedure that consistently results in a single aqueous phase and eliminates unwanted constituents. Conclusion: A robust approach to achieving reproducible, high quality samples of aqueous metabolites from lipemic sera from very high BMI subjects should be of utility in expanding metabolomics applications to lipemic biofluids.

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Advantageous Uses of Mass Spectrometry for the Quantification of Proteins

International Journal of Proteomics ◽

10.1155/2013/219452 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 15

Author(s):

John E. Hale

Keyword(s):

Mass Spectrometry ◽

Great Difficulty ◽

Immunological Methods ◽

Regulatory Agencies ◽

Protein Species ◽

Sample Handling ◽

Wide Acceptance ◽

Immunological Assays ◽

Protein Assays ◽

Very High

Quantitative protein measurements by mass spectrometry have gained wide acceptance in research settings. However, clinical uptake of mass spectrometric protein assays has not followed suit. In part, this is due to the long-standing acceptance by regulatory agencies of immunological assays such as ELISA assays. In most cases, ELISAs provide highly accurate, sensitive, relatively inexpensive, and simple assays for many analytes. The barrier to acceptance of mass spectrometry in these situations will remain high. However, mass spectrometry provides solutions to certain protein measurements that are difficult, if not impossible, to accomplish by immunological methods. Cases where mass spectrometry can provide solutions to difficult assay development include distinguishing between very closely related protein species and monitoring biological and analytical variability due to sample handling and very high multiplexing capacity. This paper will highlight several examples where mass spectrometry has made certain protein measurements possible where immunological techniques have had a great difficulty.

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Technical Note: Noble gas extraction procedure and performance of the Cologne Helix MC Plus multi-collector noble gas mass spectrometer for cosmogenic neon isotope analysis

10.5194/gchron-2021-11 ◽

2021 ◽

Author(s):

Benedikt Ritter ◽

Andreas Vogt ◽

Tibor J. Dunai

Keyword(s):

Mass Spectrometer ◽

Noble Gas ◽

Primary Standard ◽

Isotope Analysis ◽

Extraction Procedure ◽

Technical Note ◽

High Mass ◽

Experimental Setup ◽

And Performance ◽

The University

Abstract. We established a new laboratory for noble gas mass spectrometry that is dedicated for the development and application to cosmogenic nuclides at the University of Cologne (Germany). At the core of the laboratory are a state-of-the-art high mass resolution multicollector Helix MCPlus (Thermo-Fisher) noble gas mass spectrometer and a novel custom-designed automated extraction line. The Mass-spectrometer is equipped with five combined Faraday Multiplier collectors, with 1012 Ω and 1013 Ω pre-amplifiers for faraday collectors. We describe the extraction line and the automized operation procedure for cosmogenic neon and the current performance of the experimental setup. Performance tests were conducted using gas of atmospheric isotopic composition (our primary standard gas); as well as CREU-1 intercomparison material, containing a mixture of neon of atmospheric and cosmogenic composition. We use the results from repeated analysis of CREU-1 to assess the performance of the current experimental setup at Cologne. The precision in determining the abundance of cosmogenic 21Ne is equal or better than those reported for other laboratories. The absolute value we obtain for the concentration of cosmogenic 21Ne in CREU is indistinguishable from the published value.

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Predation on copepods by an Alaskan cladorhizid sponge

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315407058560 ◽

2007 ◽

Vol 87 (6) ◽

pp. 1721-1726 ◽

Cited By ~ 8

Author(s):

Les Watling

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Lipid Content ◽

Deep Sea ◽

Prey Capture ◽

Primary Process ◽

High Lipid ◽

Very High ◽

Prey Items ◽

Scanning Electron

Deep water cladorhizids are now generally thought to be carnivorous. While the methods of prey capture have been established for species of Asbestopluma, and perhaps Chondrocladia, information is sparse for species of Cladorhiza. The external morphology of the deep-sea Alaskan species, Cladorhiza corona, was examined immediately after collection, and then again later using scanning electron microscopy (SEM). All sponges examined had captured, and in most cases, fully encased, prey items which for the most part consisted of planktonic copepods. The hypothesis of this paper is that the primary process of prey capture is by means of a sticky substance and that prey stick to the sponge on contact. The abundant cladorhizid anisochelae do not seem to be arranged in a manner such that they can be used for prey capture as has been seen in Asbestopluma. Digestion of the prey occurs in a temporary cavity created by migrating sponge cells. Within this cavity lipid from the copepod is liberated, then absorbed and transported to the central part of the sponge. It is not known how much of the remaining tissue of the copepod is digested. Copepods have very high lipid content so their capture would provide the sponge with abundant energy from each prey item. The sponges seem to have their highest density in areas where bottom flow and migrating copepod numbers are both high.

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Lipid content and energy expenditure in the spawning migration of alewife (Alosa pseudoharengus) and blueback herring (Alosa aestivalis)

Canadian Journal of Zoology ◽

10.1139/z86-285 ◽

1986 ◽

Vol 64 (9) ◽

pp. 1902-1907 ◽

Cited By ~ 21

Author(s):

Robert H. Crawford ◽

R. Roland Cusack ◽

Timothy R. Parlee

Keyword(s):

Lipid Content ◽

Total Lipid Content ◽

Alosa Pseudoharengus ◽

Blueback Herring ◽

Alosa Aestivalis ◽

High Lipid ◽

Significant Difference ◽

The Difference ◽

Very High ◽

Immature Fish

For the alewife (Alosa pseudoharengus) and blueback herring (Alosa aestivalis) total lipid content was neither size nor sex specific. The lipid content of alewife and blueback herring from the LaHave River, Nova Scotia, was similar at 7.6 and 7.0%, respectively. However, in samples from the Margaree River there was a significant difference in lipid content between alewife and blueback herring (7.8% vs. 5.4%, respectively). The difference appeared to be a consequence of water temperature since late migrants of both species had a significantly lower lipid content. For alewife migration in the LaHave River, a distance of 31 km, lipid content declined by 22%, whereas in the Margaree River lipid loss was 18% over 32 km. Lipid content was also dependent on reproductive maturity, with lipid levels of 14.4, 8.7, and 5.4% in immature, prespawning, and spent alewife from site 1 on the Margaree River. Immature fish were characterized by a very high lipid content associated with the visceral organs. Protein utilization was not evident in the prespawning migration of alewife from the LaHave River. Based on lipid depletion the migration energetics of alewife in the two rivers were similar at 21.68 and 18.53 kJ∙kg−1∙km−1 in the LaHave and Margaree Rivers, respectively.

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Geochemical Fractions of the Agricultural Soils of Southern Poland and the Assessment of the Potentially Harmful Element Mobility

Minerals ◽

10.3390/min9110674 ◽

2019 ◽

Vol 9 (11) ◽

pp. 674 ◽

Cited By ~ 3

Author(s):

Gruszecka-Kosowska ◽

Baran ◽

Mazur-Kajta ◽

Czech

Keyword(s):

Risk Assessment ◽

Pore Water ◽

Ecological Risk ◽

Agricultural Soils ◽

Extraction Procedure ◽

Contamination Factor ◽

Total Content ◽

Risk Assessment Code ◽

Southern Poland ◽

Very High

Surface samples (0–25 cm each) of agricultural soils were investigated in five Regions (voivodeships) of southern Poland. The mean Potentially Harmful Element (PHE) pseudototal content ranges were as follows (mg/kg): As 5.19–10.9, Cd 0.34–1.56, Co 1.92–6.70, Cr 9.05–25.7, Cu 8.74–69.4, Hg 0.001–0.08, Ni 3.93–19.9, Pb 20.3–183, Sb 0.80–1.42, Tl 0.04–0.17, and Zn 61.3–422. The PHE availability depended on pH, the organic carbon (Corg) content, and the pseudototal PHE content in soils. Exchangeable and acid soluble PHE contents (BCRF1) determined in the Community Bureau of Reference (BCR) three-step sequential extraction procedure decreased in this order: Cd > Zn > Co > Ni = Sb > Cu > Tl > As > Cr = Pb. Actually available PHE contents in pore water (0.01 mol/dm3 CaCl2) ranged as follows: Cd 0.81–17%, Cr 0–0.25%, Cu 0.01–2.31%, Ni 0.16–2%, Pb 0.2–0.49%, and Zn 0.25–2.12%. The potential soluble total content of PHEs in pore water (0.05 mol/dm3 Na2EDTA) ranged as follows: Cd 27–91%, Cr 0.7–7.1%, Cu 6.7–98%, Ni 3.6–41%, Pb 15–41%, and Zn 3–34%. The mobility factor (MF) values indicated Cd (31.6%) and Zn (21.0%) as the most mobile elements in soil. Other PHEs followed the order of Co > Ni > Tl > As > Sb > Cu > Cr > Pb, with the MF values <10%. The risk assessment code (RAC) values revealed a very high ecological risk of Cd and Zn in the Podkarpackie Region and a high ecological risk of Cd in the Regions of Opolskie, Śląskie, Małopolskie, and Podkarpackie, and the same of Zn in the Opolskie and Śląskie. The modified risk assessment code (mRAC) index pointed a very high potential of adverse effects in soils in the Podkarpackie and a medium potential in the Opolskie, Śląskie, Małopolskie, and Świętokrzyskie. The potential adverse effect risk, described by the individual contamination factor (ICF) factor, was the following in the Regions, in the decreasing order: Cd > Pb > Sb > Zn > Co > Cu > Ni > Tl > As > Cr, and the same as described by the global contamination factor (GCF) values: Opolskie > Podkarpackie > Świętokrzyskie > Śląskie > Małopolskie.

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Influence of mesophilic and thermophilic on enrichment and chemical speciation of toxic and valuable elements in digestate

10.5194/egusphere-egu21-11277 ◽

2021 ◽

Author(s):

Nazia Zaffar ◽

Erik Ferchau ◽

Hermann Heilmeier ◽

Oliver Wiche

Keyword(s):

Sequential Extraction ◽

Ammonium Acetate ◽

Extraction Procedure ◽

Gas Production ◽

Low Grade ◽

Polluted Soils ◽

Liquid Phases ◽

Thermophilic Fermentation ◽

Thermophilic Conditions ◽

Higher Temperature

<p>Bioharvesting of toxic and valuable elements by growing high biomass crops in the regions with low-grade mining ores and metal-polluted soils is a new concept in the area of mining termed phytomining. The biomass is used in anaerobic digestion to produce biogas and digestate. To the best of our knowledge, there are limited studies on the enrichment and distribution of heavy metals and economically valuable elements in digestate, obtained from mesophilic and thermophilic fermentation conditions. This study conducted a laboratory experiment to recover and enrich toxic elements (Zn, Cd, Pb, As) and economically valuable elements (Ge and rare earth elements REEs) at mesophilic (37&#8304;C) and thermophilic (55&#8304;C) conditions. To analyze the distribution of these elements in the liquid and solid-state of digestate a three-step sequential extraction procedure was carried out. Microfiltration (0.2&#181;m) was used to separate elements in the solid and liquid phases. The solid digestate was extracted with ammonium acetate (pH 7) and ammonium acetate (pH 5) to determine exchangeable and acid-soluble elements. As a result, we found that thermophilic conditions significantly enriched Zn (3%), Cd (48%), Pb (25%), As (21%), Ge (40%), and REEs (22%) compared to mesophilic conditions. The following elements were enriched in decreasing order Cd > Ge > Pb > REEs > As > Zn. This enrichment may be due to differences in availability of substrates to microorganisms and higher gas production with increased temperature. The sequential extraction revealed that the concentration of elements in dissolved form was significantly increased in thermophilic conditions. While the concentrations in exchangeable are decreased indicating that previous elements bound on exchangeable sites were removed and transferred in solution. Furthermore, the element concentration in the residue fraction was not affected by temperature. Possibly the release of secondary metabolites from microorganisms triggered by higher temperature improved the solubility of elements which is an important prerequisite for element separation and recovery.</p><p>&#160;</p>

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Processing of Refractory Metal Borides, Carbides and Nitrides

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.395.69 ◽

2008 ◽

Vol 395 ◽

pp. 69-88 ◽

Cited By ~ 8

Author(s):

Lingappa Rangaraj ◽

Canchi Divakar ◽

Vikram Jayaram

Keyword(s):

High Temperature ◽

Composite Materials ◽

Processing Temperature ◽

Powder Mixtures ◽

Liquid Phases ◽

Metal Borides ◽

Transient Liquid Phases ◽

Processing Techniques ◽

Reactive Hot Pressing ◽

Very High

Transition metal borides, carbides and nitrides are candidates for very high temperature applications. A review of various processing techniques to fabricate dense monolithic and composite materials is presented. In particular, we focus on reactive hot pressing (RHP) which allows synthesis and densification to be achieved simultaneously. We report the RHP of composites in the Ti-B-N, Zr-B-C and Zr-B-Si-C systems using the reactions of Ti/BN, Zr/B4C (Si, SiC particulate) powder mixtures at moderate pressures and temperatures. Substantial reductions in processing temperature may be realized from those in excess of 1800°C down to as low as 1200°C by exploiting a combination of transient liquid phases, plasticity in a non-stoichiometric ZrC and enhanced transport in a sub-micron microstructure.

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In Situ Investigation of Liquid-Liquid Phase Separation in Hypermonotectic Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.649.149 ◽

2010 ◽

Vol 649 ◽

pp. 149-158 ◽

Cited By ~ 1

Author(s):

Paul L. Schaffer ◽

Ragnvald H. Mathiesen ◽

Lars Arnberg

Keyword(s):

Final Size ◽

Cast Material ◽

Size Dependent ◽

Liquid Phases ◽

Minority Phase ◽

The Matrix ◽

Inherent Problem ◽

Thermocapillary Forces ◽

Liquid Liquid Phase Separation

Hypermonotectic alloys are distinguished by a temperature region for which the homogeneous melt decomposes into two liquid phases. In Al-based hypermonotectics, the minority phase is much higher in density than the matrix melt phase and consequently macro-segregation due to sedimentation is an inherent problem when casting these alloys. However, under the correct solidification conditions, it may be feasible to counteract sedimentation by thermocapillary forces that arise due to the thermosolutal dependence of the surface tension between the two liquid phases. The current investigation involved in-situ X-ray video microscopy studies during directional solidification of Al-Bi samples of various compositions employing a Bridgman furnace. It was found that large undercoolings were required to initiate the L  L1 + L2 reaction and L2 nucleation occurred heterogeneously on the monotectic front. L2 droplets were then set in collective size-dependent motion by hydrodynamic forces coupled to external fields (i.e. temperature gradient and gravity) and internal fluctuations. The resulting flow fields are superimposed onto the short range coagulation mechanisms, such as diffusion coupling, and are all crucial in determining the final size distribution and dispersion of the Bi-rich phase in the cast material.

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Interactions between Phase-Separated Liquids and Membrane Surfaces

Applied Sciences ◽

10.3390/app11031288 ◽

2021 ◽

Vol 11 (3) ◽

pp. 1288

Author(s):

Samuel Botterbusch ◽

Tobias Baumgart

Keyword(s):

Phase Separation ◽

Liquid Phase ◽

Critical Concentration ◽

Protein Structures ◽

Lipid Vesicles ◽

Liquid Phase Separation ◽

Membrane Surfaces ◽

Liquid Phases ◽

Spherical Droplets ◽

Liquid Liquid Phase Separation

Liquid-liquid phase separation has recently emerged as an important fundamental organizational phenomenon in biological settings. Most studies of biological phase separation have focused on droplets that “condense” from solution above a critical concentration, forming so-called “membraneless organelles” suspended in solution. However, membranes are ubiquitous throughout cells, and many biomolecular condensates interact with membrane surfaces. Such membrane-associated phase-separated systems range from clusters of integral or peripheral membrane proteins in the plane of the membrane to free, spherical droplets wetting membrane surfaces to droplets containing small lipid vesicles. In this review, we consider phase-separated liquids that interact with membrane surfaces and we discuss the consequences of those interactions. The physical properties of distinct liquid phases in contact with bilayers can reshape the membrane, and liquid-liquid phase separation can construct membrane-associated protein structures, modulate their function, and organize collections of lipid vesicles dynamically. We summarize the common phenomena that arise in these systems of liquid phases and membranes.

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Technical Note: Noble gas extraction procedure and performance of the Cologne Helix MC Plus multi-collector noble gas mass spectrometer for cosmogenic neon isotope analysis

Geochronology ◽

10.5194/gchron-3-421-2021 ◽

2021 ◽

Vol 3 (2) ◽

pp. 421-431 ◽

Cited By ~ 1

Author(s):

Benedikt Ritter ◽

Andreas Vogt ◽

Tibor J. Dunai

Keyword(s):

Mass Spectrometer ◽

Noble Gas ◽

Primary Standard ◽

Isotope Analysis ◽

Extraction Procedure ◽

Technical Note ◽

High Mass ◽

Thermo Fisher Scientific ◽

And Performance ◽

Set Up

Abstract. We established a new laboratory for noble gas mass spectrometry that is dedicated to the development and application to cosmogenic nuclides at the University of Cologne (Germany). At the core of the laboratory are a state-of-the-art high-mass-resolution multicollector Helix MC Plus (Thermo Fisher Scientific) noble gas mass spectrometer and a novel custom-designed automated extraction line. The mass spectrometer is equipped with five combined Faraday multiplier collectors, with 1012 and 1013 Ω pre-amplifiers for faraday collectors. We describe the extraction line and the automated procedure for cosmogenic neon and the current performance of the experimental set-up. Performance tests were conducted using gas of atmospheric isotopic composition (our primary standard gas), as well as CREU-1 intercomparison material, containing a mixture of neon of atmospheric and cosmogenic composition. We use the results from repeated analysis of CREU-1 to assess the performance of the current experimental set-up at Cologne. The precision in determining the abundance of cosmogenic 21Ne is equal to or better than those reported for other laboratories. The absolute value we obtain for the concentration of cosmogenic 21Ne in CREU is indistinguishable from the published value.

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