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Frank Vanhaecke - One of the best experts on this subject based on the ideXlab platform.
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high precision Isotopic Analysis of essential mineral elements in biomedicine natural isotope ratio variations as potential diagnostic and or prognostic markers
Trends in Analytical Chemistry, 2016Co-Authors: Marta Costasrodriguez, Joris R Delanghe, Frank VanhaeckeAbstract:Abstract High-precision Isotopic Analysis of essential mineral elements, mainly Ca, Cu, Fe and Zn, provides relevant biomedical information. For this application, multi-collector ICP-mass spectrometry is the preferred technique. Variation in the Isotopic signature of these elements is governed by alterations in their uptake, metabolism and/or excretion. Therefore, diseases that affect mineral metal metabolism, such as hemochromatosis, cancer, liver cirrhosis and Wilson's disease, affect the Isotopic composition of these elements in some body compartments. This review discusses how natural isotope ratio variations in biofluids can potentially be exploited as alternative approaches for the diagnosis of diseases that can otherwise only be established at a later stage or via a more invasive method and/or for prognostic purposes. This discussion also includes an evaluation of the Isotopic variability in biofluids for apparently healthy individuals and in biofluids, soft tissues and bone of experimentally controlled animals. Physiological and lifestyle factors were also paid attention to.
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tandem icp mass spectrometry for sr Isotopic Analysis without prior rb sr separation
Journal of Analytical Atomic Spectrometry, 2016Co-Authors: Eduardo Oleafernandez, Lieve Alcae, Marti Resano, Frank VanhaeckeAbstract:The use of a mixture of 10% of CH3F and 90% of He as a reaction gas in tandem ICP-mass spectrometry (ICP-MS/MS) enables the accurate determination of the 87Sr/86Sr isotope ratio in geological materials, provided that mass discrimination is corrected for by using a combination of internal (Russell law, assuming a constant 88Sr/86Sr isotope ratio) and external correction (using the Isotopic reference material NIST SRM 987 SrCO3) in a sample-standard bracketing approach. No prior Rb/Sr separation is required as the isobaric overlap at a mass-to-charge ratio of 87 is avoided by monitoring SrF+ reaction product ions instead of Sr+ ions. Rb shows no reactivity towards CH3F. The double mass selection (MS/MS mode) prevents both spectral overlap from atomic ions at the mass-to-charge ratios of SrF+ reaction product ions and a measurable effect from the matrix on the 87Sr/86Sr result. This aspect is critical, as it enables accurate results to be obtained without the need for using a matrix-matched standard to correct for mass discrimination, in contrast to previous work with a quadrupole ICP-MS instrument with a CH3F/Ne-pressurized cell, in which the use of a matrix-matched standard was compulsory. The precision attainable – 0.05% RSD external precision – suffices for making the newly developed method useful in a variety of applications.
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Isotopic Analysis of cu in blood serum by multi collector icp mass spectrometry a new approach for the diagnosis and prognosis of liver cirrhosis
Metallomics, 2015Co-Authors: Marta Costasrodriguez, Joris R Delanghe, Yulia Anoshkina, Sara Lauwens, Hans Van Vlierberghe, Frank VanhaeckeAbstract:The Isotopic composition of blood serum Cu has been investigated as a potential parameter for the diagnosis and prognosis of liver cirrhosis. Serum samples from supposedly healthy women (reference population) and from a group of female patients suffering from liver cirrhosis of different etiologies were analysed. The procedure for isolation of serum Cu and the measurement protocol for its Isotopic Analysis by multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS) were evaluated. Significant differences in the Isotopic composition of Cu were observed between the reference population and the patients. A wide spread in δ65Cu was observed within the cirrhosis population and δ65Cu seems to be linked to the severity of the disease. Patients with end-stage liver disease showed a significantly lighter serum Cu Isotopic composition. Many clinical parameters used for the diagnosis and monitoring of liver diseases, i.e. the levels of aspartate aminotransferase, De Ritis ratio, prothrombin and international normalized ratio, albumin, bilirubin, Na and C-reactive protein, correlate well with the δ65Cu values, as did the ceruloplasmin level and the ceruloplasmin/Cu concentration ratio. The Isotopic composition of serum Cu appears to reveal the synthetic and hepatocellular function of the liver synergistically with inflammation and fluid retention in the cohort studied. A relevant relationship was also observed between δ65Cu and scores of mortality risk, such as the Model for End-stage Liver Disease (MELD) and MELD-Na. Thus, the Isotopic composition of serum Cu shows potential as a new approach for the prognosis of liver disease, and although further investigation is required, for evaluation of the mortality risk in end-stage liver disease and prioritization of liver transplants.
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copper and antimony Isotopic Analysis via multi collector icp mass spectrometry for provenancing ancient glass
Journal of Analytical Atomic Spectrometry, 2014Co-Authors: Lara Lobo, Patrick Degryse, Andrew Shortland, Katherine Eremi, Frank VanhaeckeAbstract:Variations in the Isotopic composition of Cu and Sb as determined using multi-collector ICP-mass spectrometry (MC-ICPMS) have been investigated as a proxy for provenancing ancient glass. Cu and Sb were added during the manufacturing of ancient (pre-Roman and Roman) glass to obtain colour and opacity. In previous work, the analytical methodology for sample digestion and isolation of Sb preceding Isotopic Analysis via multi-collector ICP-MS was developed. Although applications of Cu Isotopic Analysis can be found in the literature, this approach has not been used for provenancing glass raw materials yet. Therefore, the protocols for digestion and Cu isolation were optimized and validated, relying on the use of both an in-house multi-elemental standard and NIST SRM 610 glass reference material. The methods for Sb and Cu Isotopic Analysis were subsequently applied to a series of late Bronze Age Mesopotamian–Egyptian to Hellenistic–Roman glasses. Results obtained show that the Isotopic composition of Cu, expressed as δ65Cu, varies from −1.9 to −0.2‰, thus covering a range of approximately 2‰. Unfortunately, the use of Cu isotope ratios to characterize raw materials used in glass manufacturing is complicated by the fact that Cu ores from within a single deposit can exhibit a similar range in δ65Cu values, certainly for co-existing Cu sulfides and oxides. Sb in stibnite ore, on the other hand, only shows a variance in Isotopic composition of ∼10 e units (or 0.1‰), but Sb Isotopic Analysis offers more potential to pinpoint the location of an antimony source used in antiquity.
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isotopes on the beach part 2 neodymium Isotopic Analysis for the provenancing of roman glass making
Archaeometry, 2013Co-Authors: Diete Ems, Frank Vanhaecke, Lieve Alcae, Monica Ganio, Kris Latruwe, Mike Carremans, D Gimeno, Alberta Silvestri, Philippe Muchez, Patrick DegryseAbstract:In this study, we have evaluated the applicability of Nd Isotopic Analysis for the provenancing of Roman glass and we present a database of Nd Isotopic compositions of possible sand raw materials from the western Mediterranean, as a means of comparison for the growing number of Isotopic studies on ancient glass. The 143Nd/144Nd isotope ratio of sands is a good indicator for their geological (and sometimes geographical) provenance. The use of the Isotopic signature of Nd as a proxy for the source of silica in glass is, however, not always straightforward because of the possible overlap of signatures from different suppliers.
Stanley H Ambrose - One of the best experts on this subject based on the ideXlab platform.
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reconstructing northern chinese neolithic subsistence practices by Isotopic Analysis
Journal of Archaeological Science, 2005Co-Authors: Ekaterina A Pechenkina, Stanley H Ambrose, Ma Xiaolin, Robert A BenferAbstract:Stable isotope signatures of both human and non-human animal bone samples indicate that Neolithic farmers of the Yellow and Wei River basins in China potentially cultivated millet for two reasons: as a staple for human consumption and as fodder for domesticated animals, specifically pigs, dogs, and perhaps chicken. Bone samples were analyzed from four Neolithic sites: Jiangzhai, Shijia, Xipo, and Kangjia, spanning the time period from 7000 to 4000 years ago. A combination of very high carbon isotope ratios (d 13 CZ 7.7G 0.4&) and low nitrogen isotope ratios (d 15 N Z 7.5G 0.5&) in samples of Xipo pig and dog bone suggests that these monogastric animals consumed substantial quantities of C4 plants, almost certainly millets. In fact, the proportion of C4 plants in animal diets appears to have been even greater than that in human diet. Stable isotope values (d 13 C Z10.0 G 0.8&; d 15 NZ 8.3 G 0.5&) of human bone collagen recovered at Jiangzhai and Shijia indicate a staple role for millets, as well as the consumption of both wild and other non-C4 domesticated plant foods. As millet agriculture and animal husbandry apparently depended on one another, a strong mutualism between them was likely established in northern China during the Neolithic. We propose that variable redistribution of agricultural products between humans and animals, depending on the availability of wild resources and annual fluctuations in agricultural output, helped ensure the stability of Neolithic human subsistence in the Yellow and Wei River basins. 2005 Elsevier Ltd. All rights reserved.
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status and gender differences in diet at mound 72 cahokia revealed by Isotopic Analysis of bone
Journal of Anthropological Archaeology, 2003Co-Authors: Stanley H Ambrose, Jane E Uikstra, Harold W KruegeAbstract:Abstract Cahokia Mound 72 contains 272 human burials dating to the Lohmann and early Stirling phases (ca. 1050–1150 AD) of the Mississippian period. Substantial status- and gender-related differences in burial style are apparent. Some burials are associated with large quantities of prestigious grave goods, suggesting high status. Mass graves of young adult females with skeletal indicators of poor health suggest low status and nutritional stress. Nitrogen isotope ratios of bone collagen show that high status individuals ate much more animal protein, but carbon isotope ratios of collagen suggest these individuals ate only ca. 10% less maize than lower status individuals. Apatite carbon isotopes show low status females ate ca. 60% more maize than high status individuals, which confirms the large nitrogen isotope difference of females in mass graves. These results indicate high and low status individuals had significantly different diet compositions and nutritional qualities. The stable isotope evidence supports paleopathological data for status-related differences in health, and dental morphological data for presumed genetic differences in origin. These data also provide insights into the nutrition- and health-related dimension of regional hierarchical organization of settlements and social inequality of this complex chiefdom in the greater Cahokia region.
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the seasonal mobility model for prehistoric herders in the south western cape of south africa assessed by Isotopic Analysis of sheep tooth enamel
Journal of Archaeological Science, 2002Co-Authors: Marie Alasse, Stanley H Ambrose, Andrew Smith, Douglas T PriceAbstract:Abstract A pattern of seasonal mobility between the coast and the hinterland by Khoekhoe pastoralists in the south-western Cape of South Africa was documented at the time of European contact. Because the region is characterized by a mosaic of geological substrates of various ages and vegetation types with different proportions of C 3 and C 4 plants, this mobility model for prehistoric herders can be tested by Analysis of carbon, oxygen and strontium isotope ratios in domestic bovid tooth enamel. Isotopic Analysis was performed on archaeological sheep, cattle, eland and steenbok teeth from the Late Stone Age site of Kasteelberg on the Vredenburg Peninsula. Sequential sampling of enamel provided a chronological record of the Isotopic composition of diet during tooth formation. Results from carbon and oxygen isotope Analysis of archaeological and modern steenbok teeth show seasonal variation in the δ 13 C of local pastures in the vicinity of the site (up to 2·9‰ in a single individual), which could be due to seasonal change in proportions of C 3 and C 4 plants and/or seasonal variation in the δ 13 C of C 3 plants. A pattern of seasonal change of 0·9–3·5‰ in the δ 13 C of tooth enamel is also observed in the sheep teeth. This amplitude of variation could be due to local seasonal changes, thus it is not possible, from the δ 13 C values, to infer whether the sheep were moving seasonally. Results from 87 Sr/ 86 Sr Analysis of two sheep suggest that one individual stayed all year round on the coast, whereas the other had grazed in the interior for part of its life. Both δ 13 C and 87 Sr/ 86 Sr values measured in a cow tooth suggest that this animal spent part of its life in the interior, even though it died at Kasteelberg. Results on this cow also suggest longer residence within habitats rather than seasonal mobility. A clear pattern of seasonal mobility between the coast and the interior has not been shown for prehistoric pastoralists. However, the pattern of mobility attested in historical times might have developed only later in prehistory, when cattle pastoralism developed in the region.
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stable Isotopic Analysis of human diet in the marianas archipelago western pacific
American Journal of Physical Anthropology, 1997Co-Authors: Stanley H Ambrose, Ia M Utle, Douglas Hanso, Rosalind L Hunteranderso, Harold W KruegeAbstract:Proportions of marine vs. terrestrial resources in prehistoric human diets in the southern Mariana Islands (Guam, Rota, Saipan), Micronesia, have been estimated by Analysis of stable isotope ratios of carbon and nitrogen in bone collagen and of carbon in apatite. The Isotopic composition of marine and terrestrial food resources from the Marianas have also been determined. Experimental evidence shows that collagen carbon isotopes mainly reflect those of dietary protein sources and thus overestimate the contribution of marine animal foods. Marine protein consumption apparently ranges from ∼20% to ∼50% on these islands. Experiments also demonstrate the carbon isotope ratio of bone apatite carbonate accurately reflects that of the whole diet. Carbonate carbon isotope data suggest some individuals consumed significant amounts of 13C-enriched (C4) plants or seaweeds. Sugar cane is an indigenous C4 crop and seaweeds are eaten throughout the Pacific, but they have not been considered by archaeologists to have been prehistoric dietary staples. Apatite carbon isotope Analysis has apparently identified previously unrecognized prehistoric dietary adaptations in the Mariana Islands, but this must be confirmed by archaeobotanical evidence. Am J Phys Anthropol 104:343–361, 1997. © 1997 Wiley-Liss, Inc.
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preparation and characterization of bone and tooth collagen for Isotopic Analysis
Journal of Archaeological Science, 1990Co-Authors: Stanley H AmbroseAbstract:Abstract Criteria are presented for the identification of diagenetic alteration of carbon and nitrogen isotope ratios of bone and tooth collagen prepared by a widely used method. Measurements of collagen concentrations in tooth and bone, atomic C:N ratios, and carbon and nitrogen concentrations in collagen of 359 historic and prehistoric African humans, and modern and prehistoric East African non-human mammals are described. Carbon isotope ratios of collagen lipids from four bones are also presented. Compared to bone, whole teeth have significantly lower collagen concentrations, lower carbon and nitrogen concentrations in collagen, and similar C:N ratios. Carbon and nitrogen concentrations and C:N ratios are relatively constant over a wide range of collagen concentrations. However, prehistoric specimens with very low collagen concentrations have highly variable C:N ratios, very low carbon and nitrogen concentrations in collagen, and stable carbon and nitrogen isotope ratios unlike collagen. At the transition from well-preserved to poorly preserved collagen the most reliable indicator of collagen preservation is the concentration of carbon and nitrogen in collagen. Concentrations of C and N drop abruptly by an order of magnitude at this transition point. These attributes provide simple criteria for assessing sample quality. Since collagen preservation can vary greatly within prehistoric sites, these attributes should be reported for each specimen. Use of purification procedures that remove acid- and base-soluble contaminants and particulate matter (carbonates, fulvic acids, lipids, humic acids, sediments and rootlets) are recommended. Wider adoption of these procedures would insure comparability of results between laboratories, and permit independent and objective evaluation of sample preservation, and more precise dietary, climatic, and habitat interpretations of collagen Isotopic analyses.
Victoria J Orpha - One of the best experts on this subject based on the ideXlab platform.
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spatially resolved capture of hydrogen sulfide from the water column and sedimentary pore waters for abundance and stable Isotopic Analysis
Marine Chemistry, 2017Co-Authors: David A Fike, J L Houghto, S E Moore, William P Gilhooly, Katherine S Dawso, Gregory K Druschel, Ja P Amend, Victoria J OrphaAbstract:Sulfur cycling is ubiquitous in sedimentary environments, where it plays a major role in mediating carbon remineralization and impacts both local and global redox budgets. Microbial sulfur cycling is dominated by metabolic activity that either produces (e.g., sulfate reduction, disproportionation) or consumes (sulfide oxidation) hydrogen sulfide (H_2S). As such, improved constraints on the production, distribution, and consumption of H_2S in the natural environment will increase our understanding of microbial sulfur cycling. These different microbial sulfur metabolisms are additionally associated with particular stable Isotopic fractionations. Coupling measurements of the Isotopic composition of the sulfide with its distribution can provide additional information about environmental conditions and microbial ecology. Here we investigate the kinetics of sulfide capture on photographic films as a way to document the spatial distribution of sulfide in complex natural environments as well as for in situ capture of H_2S for subsequent stable Isotopic Analysis. Laboratory experiments and timed field deployments demonstrate the ability to infer ambient sulfide abundances from the yield of sulfide on the films. This captured sulfide preserves the Isotopic composition of the ambient sulfide, offset to slightly lower δ^(34)S values by ~ 1.2 ± 0.5‰ associated with the diffusion of sulfide into the film and subsequent reaction with silver to form Ag_2S precipitates. The resulting data enable the exploration of cm-scale lateral heterogeneity that complement most geochemical profiles using traditional techniques in natural environments. Because these films can easily be deployed over a large spatial area, they are also ideal for real-time assessment of the spatial and temporal dynamics of a site during initial reconnaissance and for integration over long timescales to capture ephemeral processes.
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quantification and Isotopic Analysis of intracellular sulfur metabolites in the dissimilatory sulfate reduction pathway
AGUFM, 2017Co-Authors: Victoria J Orpha, Min Sub Sim, Guillaume Paris, Jess F Adkins, Ale L SessionsAbstract:Microbial sulfate reduction exhibits a normal isotope effect, leaving unreacted sulfate enriched in ^(34)S and producing sulfide that is depleted in ^(34)S. However, the magnitude of sulfur isotope fractionation is quite variable. The resulting changes in sulfur isotope abundance have been used to trace microbial sulfate reduction in modern and ancient ecosystems, but the intracellular mechanism(s) underlying the wide range of fractionations remains unclear. Here we report the concentrations and Isotopic ratios of sulfur metabolites in the dissimilatory sulfate reduction pathway of Desulfovibrio alaskensis. Intracellular sulfate and APS levels change depending on the growth phase, peaking at the end of exponential phase, while sulfite accumulates in the cell during stationary phase. During exponential growth, intracellular sulfate and APS are strongly enriched in ^(34)S. The fractionation between internal and external sulfate is up to 49‰, while at the same time that between external sulfate and sulfide is just a few permil. We interpret this pattern to indicate that enzymatic fractionations remain large but the net fractionation between sulfate and sulfide is muted by the closed-system limitation of intracellular sulfate. This ‘reservoir effect’ diminishes upon cessation of exponential phase growth, allowing the expression of larger net sulfur isotope fractionations. Thus, the relative rates of sulfate exchange across the membrane versus intracellular sulfate reduction should govern the overall (net) fractionation that is expressed. A strong reservoir effect due to vigorous sulfate reduction might be responsible for the well-established inverse correlation between sulfur isotope fractionation and the cell-specific rate of sulfate reduction, while at the same time intraspecies differences in sulfate uptake and/or exchange rates could account for the significant scatter in this relationship. Our approach, together with ongoing investigations of the kinetic isotope fractionation by key enzymes in the sulfate reduction pathway, should provide an empirical basis for a quantitative model relating the magnitude of microbial isotope fractionation to their environmental and physiological controls.
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molecular and Isotopic Analysis of anaerobic methane oxidizing communities in marine sediments
Organic Geochemistry, 2000Co-Authors: Kai-uwe Hinrichs, Victoria J Orpha, Roge E Summons, Sea P Sylva, J M HayesAbstract:Convergent lines of molecular, carbon-Isotopic, and phylogenetic evidence have previously indicated (Hinrichs, K.-U., Hayes, J.M., Sylva, S.P., Brewer, P.G., DeLong, E. F., 1999. Methane-consuming archaebacteria in marine sediments. Nature 398, 802–805.) that archaea are involved in the anaerobic oxidation of methane in sediments from the Eel River Basin, offshore northern California. Now, further studies of those same sediments and of sediments from a methane seep in the Santa Barbara Basin have confirmed and extended those results. Mass spectrometric and chromatographic analyses of an authentic standard of sn-2-hydroxyarchaeol (hydroxylated at C-3 in the sn-2 phytanyl moiety) have confirmed our previous, tentative identification of this compound but shown that the previously examined product was the mono-TMS, rather than di-TMS, derivative. Further analyses of ^(13)C-depleted lipids, appreciably more abundant in samples from the Santa Barbara Basin, have shown that the archaeal lipids are accompanied by two sets of products that are only slightly less depleted in ^(13)C. These are additional glycerol ethers and fatty acids. The alkyl substituents in the ethers (mostly monoethers, with some diethers) are non-isoprenoidal. The carbon-number distributions and Isotopic compositions of the alkyl substituents and of the fatty acids are similar, suggesting strongly that they are produced by the same organisms. Their structures, n-alkyl and methyl-branched n-alkyl, require a bacterial rather than archaeal source. The non-isoprenoidal glycerol ethers are novel constituents in marine sediments but have been previously reported in thermophilic, sulfate- and nitrate-reducing organisms which lie near the base of the rRNA-based phylogenetic tree. Based on previous observations that the anaerobic oxidation of methane involves a net transfer of electrons from methane to sulfate, it appears likely that the non-archaeal, ^(13)C-depleted lipids are products of one or more previously unknown sulfate-reducing bacteria which grow syntrophically with the methane-utilizing archaea. Their products account for 50% of the fatty acids in the sample from the Santa Barbara Basin. At all methane-seep sites examined, the preservation of aquatic products is apparently enhanced because the methane-oxidizing consortium utilizes much of the sulfate that would otherwise be available for remineralization of materials from the water column.
James R Ehleringer - One of the best experts on this subject based on the ideXlab platform.
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water extraction times for plant and soil materials used in stable isotope Analysis
Rapid Communications in Mass Spectrometry, 2006Co-Authors: Adam G West, Shela J Patrickson, James R EhleringerAbstract:Stable Isotopic Analysis of water for many ecological applications commonly requires extractions of water from dozens to hundreds of plant and soil samples. With recent advances in mass spectrometry, water extraction, rather than the Isotopic Analysis itself, is the bottleneck in sample processing. Using cryogenic vacuum distillation, we have created extraction timing curves to determine how much time (Tmin) is required to extract an unfractionated water sample. Our results indicated that Tmin values are 60 to 75 min for stems, 40 min for clay soils, 30 min for sandy soils and 20 to 30 min for leaves. While the extraction times reported here may allow for some reductions relative to times reported in the literature, the extraction process will continue to be a rate-limiting step in plant water analyses. Ultimately, technological advances eliminating the need for extraction are required to greatly increase throughput rates in water isotope Analysis for ecological research. Copyright © 2006 John Wiley & Sons, Ltd.
Brian L Beard - One of the best experts on this subject based on the ideXlab platform.
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correction of instrumentally produced mass fractionation during Isotopic Analysis of fe by thermal ionization mass spectrometry
International Journal of Mass Spectrometry, 1999Co-Authors: Clark M Johnson, Brian L BeardAbstract:High-precision (∼0.015%/mass) isotope ratio measurements of Fe may be obtained by using magnetic-sector thermal ionization mass spectrometry (TIMS), where rigorous correction of instrumentally produced mass fractionation can be made. Such corrections are best done by using a double-spike approach, which was first introduced several decades ago. However, previous derivations do not lend themselves to the high-precision isotope Analysis that modern TIMS instruments are capable of because of various assumptions of mass fractionation laws or constant atomic weights. Moreover, some of these previous approaches took iterative approaches to the calculation, and none presented detailed error propagations. Here we present a completely general derivation to the double-spike approach that may be used for any appropriate isotope system and is applicable to the mass fractionation laws that are known to occur in TIMS. In addition, we present an assessment of error propagation as a function of algorithm and spike isotope composition. This approach has produced the highest precision Fe isotope ratio measurements yet reported, on the order of ±0.2 to 0.3 per mil for the 54Fe/56Fe ratio, that correct for instrumentally produced mass fractionation and yet retain natural, mass-dependent Isotopic variations in samples.