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  1 / 51643 MEDLINE  
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PMID:29364968
Autor:Petersone-Gordina E; Roberts C; Millard AR; Montgomery J; Gerhards G
Endereço:Department of Archaeology, Durham University, Durham, United Kingdom.
Título:Dental disease and dietary isotopes of individuals from St Gertrude Church cemetery, Riga, Latvia.
Fonte:PLoS One; 13(1):e0191757, 2018.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:This research explores oral health indicators and stable carbon and nitrogen isotope data to explore diet, and differences in diet, between people buried in the four different contexts of the St Gertrude Church cemetery (15th- 17th centuries AD): the general cemetery, two mass graves, and a collective mass burial pit within the general cemetery. The main aim is to assess whether people buried in the mass graves were rural immigrants, or if they were more likely to be the victims of plague (or another epidemic) who lived in Riga and its suburbs. The data produced (from dental disease assessments and isotope analyses) were compared within, as well as between, the contexts. Most differences emerged when comparing the prevalence rates of dental diseases and other oral health indicators in males and females between the contexts, while isotope analysis revealed more individual, rather than context-specific, differences. The data suggested that the populations buried in the mass graves were different from those buried in the general cemetery, and support the theory that rural immigrants were buried in both mass graves. Significant differences were observed in some aspects of the data between the mass graves, however, possibly indicating that the people buried in them do not represent the same community.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Nome de substância:0 (Carbon Isotopes); 0 (Nitrogen Isotopes)


  2 / 51643 MEDLINE  
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PMID:29175406
Autor:Sohn SY; Kuntze K; Nijenhuis I; Häggblom MM
Endereço:Department of Biochemistry and Microbiology, School of Environmental and Biological Sciences, Rutgers University, 76 Lipman Drive, New Brunswick, NJ 08901, USA.
Título:Evaluation of carbon isotope fractionation during anaerobic reductive dehalogenation of chlorinated and brominated benzenes.
Fonte:Chemosphere; 193:785-792, 2018 Feb.
ISSN:1879-1298
País de publicação:England
Idioma:eng
Resumo:Compound specific stable isotope analysis (CSIA) has been established as a useful tool to evaluate in situ biodegradation. Here, CSIA was used to determine microbial dehalogenation of chloro- and bromobenzenes in microcosms derived from Hackensack River sediments. Gas chromatography-isotope ratio mass spectrometry (GC-IRMS) was used to measure carbon isotope fractionation during reductive dehalogenation of hexachlorobenzene (HCB), pentachlorobenzene (PeCB), 1,2,3,5-tetrachlorobenzene (TeCB), 1,2,3,5-tetrabromobenzene (TeBB), and 1,3,5-tribromobenzene (TriBB). Strong evidence of isotope fractionation coupled to dehalogenation was not observed in the substrate, possibly due to the low solubilities of the highly halogenated benzene substrates and a dilution of the isotope signal. Nonetheless, we could measure a depletion of the δ C value in the dichlorobenzene product during dechlorination of HCB, the sequential depletion and enrichment of δ C value for trichlorobenzene in TeCB dechlorinating cultures, and the enrichment of δ C during debromination of TriBB. This indicates that a measurable isotope fractionation occurred during reductive dehalogenation of highly halogenated chloro- and bromobenzenes in aquatic sediments. Thus, although more quantitative measurements will be needed, the data suggests that CSIA may have application for monitoring in situ microbial reductive dehalogenation of highly halogenated benzenes.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Bromobenzenes); 0 (Carbon Isotopes); 0 (Chlorobenzenes); J64922108F (Benzene)


  3 / 51643 MEDLINE  
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PMID:29343713
Autor:Hare VJ; Loftus E; Jeffrey A; Ramsey CB
Endereço:Research Laboratory for Archaeology and the History of Art, School of Archaeology, University of Oxford, 1 South Parks Road, Oxford, OX1 3TG, UK. vincent.john.hare@gmail.com.
Título:Atmospheric CO effect on stable carbon isotope composition of terrestrial fossil archives.
Fonte:Nat Commun; 9(1):252, 2018 01 17.
ISSN:2041-1723
País de publicação:England
Idioma:eng
Resumo:The C/ C ratio of C plant matter is thought to be controlled by the isotopic composition of atmospheric CO and stomatal response to environmental conditions, particularly mean annual precipitation (MAP). The effect of CO concentration on C/ C ratios is currently debated, yet crucial to reconstructing ancient environments and quantifying the carbon cycle. Here we compare high-resolution ice core measurements of atmospheric CO with fossil plant and faunal isotope records. We show the effect of pCO during the last deglaciation is stronger for gymnosperms (-1.4 ± 1.2‰) than angiosperms/fauna (-0.5 ± 1.5‰), while the contributions from changing MAP are -0.3 ± 0.6‰ and -0.4 ± 0.4‰, respectively. Previous studies have assumed that plant C/ C ratios are mostly determined by MAP, an assumption which is sometimes incorrect in geological time. Atmospheric effects must be taken into account when interpreting terrestrial stable carbon isotopes, with important implications for past environments and climates, and understanding plant responses to climate change.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Nome de substância:0 (Carbon Isotopes); 142M471B3J (Carbon Dioxide)


  4 / 51643 MEDLINE  
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PMID:29232607
Autor:Chowdhury EA; Alqahtani F; Bhattacharya R; Mehvar R; Bickel U
Endereço:Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA; Center for Blood-Brain Barrier Research, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX, USA.
Título:Simultaneous UPLC-MS/MS analysis of two stable isotope labeled versions of sucrose in mouse plasma and brain samples as markers of blood-brain barrier permeability and brain vascular space.
Fonte:J Chromatogr B Analyt Technol Biomed Life Sci; 1073:19-26, 2018 Jan 15.
ISSN:1873-376X
País de publicação:Netherlands
Idioma:eng
Resumo:Blood Brain Barrier (BBB) permeability is frequently compromised in the course of diseases affecting the central nervous system (CNS). Sucrose is a low molecular weight, hydrophilic marker with slow permeability at the naive BBB and therefore one of the widely used indicators of barrier integrity. Our laboratory recently developed a highly sensitive UPLC-MS/MS method for stable isotope labeled [ C ]sucrose in biological matrices. Correction of total brain concentration for contribution of intravascular space is required in such experiments in order to accurately measure BBB permeability, and it is often accomplished by vascular perfusion with buffer solutions prior to brain sampling. The purpose of the present study was to develop a UPLC-MS/MS method, which allows simultaneous analysis of two different stable isotope labeled sucrose variants, one of which can be utilized as a vascular marker. The first analyte, [ C ]sucrose, serves to quantify brain uptake clearance as a measure of BBB permeability, while the second analyte, [ C ]sucrose, is administered just before termination of the animal experiment and is considered as the vascular marker. [ H ]sucrose is used as the internal standard for both C labeled compounds. Because the majority of recent studies on CNS diseases employ mice, another objective was to validate the new technique in this species. The UPLC-MS/MS method was linear (r ≥ 0.99) in the tested concentration ranges, from 10 to 1000 ng/mL for both analytes in plasma, from 2 to 400 ng/g [ C ]sucrose in brain and from 10 to 400 ng/g [ C ]sucrose in brain. It was also validated in terms of acceptable intra and inter run accuracy and precision values (n = 5). The dual analyte technique was applied in a study in mice. One group received intravenous bolus injections of 10 mg/kg [ C ]sucrose at time 0, and 10 mg/kg [ C ]sucrose at 14.5 min, and subsequent terminal blood and brain sampling was performed at 15 min. For comparison, another group received an intravenous bolus dose of 10 mg/kg [ C ]sucrose and was submitted to transcardiac perfusion with buffer after 15 min. We demonstrate that the two alternative techniques to correct for intravascular content deliver equivalent values for brain concentration and brain uptake clearance.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Biomarkers); 0 (Carbon Isotopes); 57-50-1 (Sucrose)


  5 / 51643 MEDLINE  
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PMID:29381065
Autor:Lin N; Chen S; Zhang H; Li J; Fu L
Título:Quantification of Major Royal Jelly Protein 1 in Fresh Royal Jelly by Ultraperformance Liquid Chromatography-Tandem Mass Spectrometry.
Fonte:J Agric Food Chem; 66(5):1270-1278, 2018 Feb 07.
ISSN:1520-5118
País de publicação:United States
Idioma:eng
Resumo:Major royal jelly protein 1 (MRJP1) is the most abundant protein in royal jelly (RJ), and the level of MRJP1 has been suggested as a promising parameter for standardization and evaluation of RJ authenticity in quality. Here, a quantitative method was developed for the quantification of MRJP1 in RJ based on a signature peptide and a stable isotope-labeled internal standard peptide FFDYDFGSDER*(R*, C , N ) by ultraperformance liquid chromatography-tandem mass spectrometry. Recoveries of the established method ranged from 85.33 to 95.80%, and both the intra- and interday precision were RSD < 4.97%. Quantification results showed that content of MRJP1 in fresh RJ was 41.96-55.01 mg/g. Abnormal levels of MRJP1 were found in three commercial RJs and implied that these samples were of low quality and might be adulterated. Results of the present work suggested that the developed method could be successfully applied to quantify MRJP1 in RJ and also could evaluate the quality of RJ.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Carbon Isotopes); 0 (Fatty Acids); 0 (Glycoproteins); 0 (Insect Proteins); 0 (MRJP1 protein, Apis mellifera); 0 (Nitrogen Isotopes); 0 (Peptide Fragments); L497I37F0C (royal jelly)


  6 / 51643 MEDLINE  
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PMID:29293647
Autor:Hofman-Kaminska E; Bocherens H; Borowik T; Drucker DG; Kowalczyk R
Endereço:Mammal Research Institute, Polish Academy of Sciences, Bialowieza, Poland.
Título:Stable isotope signatures of large herbivore foraging habitats across Europe.
Fonte:PLoS One; 13(1):e0190723, 2018.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:We investigated how do environmental and climatic factors, but also management, affect the carbon (δ13C) and nitrogen (δ15N) stable isotope composition in bone collagen of the two largest contemporary herbivores: European bison (Bison bonasus) and moose (Alces alces) across Europe. We also analysed how different scenarios of population recovery- reintroduction in bison and natural recovery in moose influenced feeding habitats and diet of these two species and compared isotopic signatures of modern populations of bison and moose (living in human-altered landscapes) with those occurring in early Holocene. We found that δ13C of modern bison and moose decreased with increasing forest cover. Decreasing forest cover, increasing mean annual temperature and feeding on farm crops caused an increase in δ15N in bison, while no factor significantly affected δ15N in moose. We showed significant differences in δ13C and δ15N among modern bison populations, in contrast to moose populations. Variation in both isotopes in bison resulted from inter-population differences, while in moose it was mainly an effect of intra-population variation. Almost all modern bison populations differed in δ13C and δ15N from early Holocene bison. Such differences were not observed in moose. It indicates refugee status of European bison. Our results yielded evidence that habitat structure, management and a different history of population recovery have a strong influence on foraging behaviour of large herbivores reflected in stable isotope signatures. Influence of forest structure on carbon isotope signatures of studied herbivores supports the "canopy effect" hypothesis.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Nome de substância:0 (Carbon Isotopes); 0 (Nitrogen Isotopes)


  7 / 51643 MEDLINE  
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PMID:28987410
Autor:Woods A; Kuntze K; Gelman F; Halicz L; Nijenhuis I
Endereço:Department for Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstrasse 15, D-04318, Leipzig, Germany.
Título:Variable dual carbon-bromine stable isotope fractionation during enzyme-catalyzed reductive dehalogenation of brominated ethenes.
Fonte:Chemosphere; 190:211-217, 2018 Jan.
ISSN:1879-1298
País de publicação:England
Idioma:eng
Resumo:The potential of compound-specific stable isotope analysis (CSIA) to characterize biotransformation of brominated organic compounds (BOCs) was assessed and compared to chlorinated analogues. Sulfurospirillum multivorans and Desulfitobacterium hafniense PCE-S catalyzed the dehalogenation of tribromoethene (TBE) to either vinyl bromide (VB) or ethene, respectively. Significantly lower isotope fractionation was observed for TBE dehalogenation by S. multivorans (ε = -1.3 ± 0.2‰) compared to D. hafniense (ε = -7.7 ± 1.5‰). However, higher fractionation was observed for dibromoethene (DBE) dehalogenation by S. multivorans (ε = -16.8 ± 1.8‰ and -21.2 ± 1.6‰ for trans- and cis-1,2- (DBE) respectively), compared to D. hafniense PCE-S (ε = -9.5 ± 1.2‰ and -14.5 ± 0.7‰ for trans-1,2-DBE and cis-1,2-DBE, respectively). Significant, but similar, bromine fractionation was observed for for S. multivorans (ε = -0.53 ± 0.15‰, -1.03 ± 0.26‰, and -1.18 ± 0.13‰ for trans-1,2-DBE, cis-1,2-DBE and TBE, respectively) and D. hafniense PCE-S (ε = -0.97 ± 0.28‰, -1.16 ± 0.36‰, and -1.34 ± 0.32‰ for cis-1,2-DBE, TBE and trans-1,2-DBE, respectively). Variable CBr dual-element slopes were estimated at Λ (ε /ε ) = 1.03 ± 0.2, 17.9 ± 5.8, and 29.9 ± 11.0 for S. multivorans debrominating TBE, cis-1,2-DBE and trans-1,2-DBE, respectively, and at 7.14 ± 1.6, 8.27 ± 3.7, and 8.92 ± 2.4 for D. hafniense PCE-S debrominating trans-1,2-DBE, TBE and cis-1,2-DBE, respectively. A high variability in isotope fractionation, which was substrate property related, was observed for S. multivorans but not D. hafniense, similar as observed for chlorinated ethenes, and may be due to rate-limiting steps preceding the bond-cleavage or differences in the reaction mechanism. Overall, significant isotope fractionation was observed and, therefore, CSIA can be applied to monitor the fate of brominated ethenes in the environment. Isotope effects differences, however, are not systematically comparable to chlorinated ethenes.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Carbon Isotopes); 1N41638RNO (Ethylene Dibromide); 7440-44-0 (Carbon); SBV4XY874G (Bromine)


  8 / 51643 MEDLINE  
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PMID:28452454
Autor:Wibowo A; Park JM; Liu SC; Khosla C; Spielman DM
Endereço:Department of Biochemistry, Stanford University , Stanford, California 94305, United States.
Título:Real-Time in Vivo Detection of H O Using Hyperpolarized C-Thiourea.
Fonte:ACS Chem Biol; 12(7):1737-1742, 2017 Jul 21.
ISSN:1554-8937
País de publicação:United States
Idioma:eng
Resumo:Reactive oxygen species (ROS) are essential cellular metabolites widely implicated in many diseases including cancer, inflammation, and cardiovascular and neurodegenerative disorders. Yet, ROS signaling remains poorly understood, and their measurements are a challenge due to high reactivity and instability. Here, we report the development of C-thiourea as a probe to detect and measure H O dynamics with high sensitivity and spatiotemporal resolution using hyperpolarized C magnetic resonance spectroscopic imaging. In particular, we show C-thiourea to be highly polarizable and to possess a long spin-lattice relaxation time (T ), which enables real-time monitoring of ROS-mediated transformation. We also demonstrate that C-thiourea reacts readily with H O to give chemically distinguishable products in vitro and validate their detection in vivo in a mouse liver. This study suggests that C-thiourea is a promising agent for noninvasive detection of H O in vivo. More broadly, our findings outline a viable clinical application for H O detection in patients with a range of diseases.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Carbon Isotopes); 0 (Lipids); 0 (Proteins); 0 (Reactive Oxygen Species); 9007-49-2 (DNA); BBX060AN9V (Hydrogen Peroxide); GYV9AM2QAG (Thiourea)


  9 / 51643 MEDLINE  
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PMID:27771467
Autor:Juras A; Chylenski M; Krenz-Niedbala M; Malmström H; Ehler E; Pospieszny L; Lukasik S; Bednarczyk J; Piontek J; Jakobsson M; Dabert M
Endereço:Department of Human Evolutionary Biology, Institute of Anthropology, Faculty of Biology, Adam Mickiewicz University in Poznan, Umultowska 89, 61-614 Poznan, Poland. Electronic address: annaj@amu.edu.pl.
Título:Investigating kinship of Neolithic post-LBK human remains from Krusza Zamkowa, Poland using ancient DNA.
Fonte:Forensic Sci Int Genet; 26:30-39, 2017 01.
ISSN:1878-0326
País de publicação:Netherlands
Idioma:eng
Resumo:We applied an interdisciplinary approach to investigate kinship patterns and funerary practices during the middle Neolithic. Genetic studies, radiocarbon dating, and taphonomic analyses were used to examine two grave clusters from Krusza Zamkowa, Poland. To reconstruct kinship and determine biological sex, we extracted DNA from bones and teeth, analyzed mitochondrial genomes and nuclear SNPs using the HID-Ion AmpliSeq™ Identity panel generated on Illumina and Ion Torrent platforms, respectively. We further dated the material (AMS C) and to exclude aquatic radiocarbon reservoir effects, measures of carbon and nitrogen stable isotopes for diet reconstruction were used. We found distinct mitochondrial genomes belonging to haplogroups U5b2a1a, K1c and H3d in the first grave cluster, and excluded maternal kin patterns among the three analyzed individuals. In the second grave cluster one individual belonged to K1a4. However, we could not affiliate the second individual to a certain haplogroup due to the fragmented state of the mitochondrial genome. Although the individuals from the second grave cluster differ at position 6643, we believe that more data is needed to fully resolve this issue. We retrieved between 26 and 77 autosomal SNPs from three of the individuals. Based on kinship estimations, taking into account the allelic dropout distribution, we could not exclude first degree kin relation between the two individuals from the second grave cluster. We could, however, exclude a first degree kinship between these two individuals and an individual from the first grave cluster. Presumably, not only biological kinship, but also social relations played an important role in the funerary practice during this time period. We further conclude that the HID-Ion AmpliSeq™ Identity Panel may prove useful for first degree kin relation studies for samples with good DNA preservation, and that mitochondrial genome capture enrichment is a powerful tool for excluding direct maternal relationship in ancient individuals.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Nome de substância:0 (Carbon Isotopes); 0 (DNA, Ancient); 0 (DNA, Mitochondrial); 0 (Nitrogen Isotopes)


  10 / 51643 MEDLINE  
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PMID:28453883
Autor:Vráblová M; Vrábl D; Hronková M; Kubásek J; Santrucek J
Endereço:Faculty of Science, University of South Bohemia, Ceské Budejovice, Czech Republic.
Título:Stomatal function, density and pattern, and CO assimilation in Arabidopsis thaliana tmm1 and sdd1-1 mutants.
Fonte:Plant Biol (Stuttg); 19(5):689-701, 2017 Sep.
ISSN:1438-8677
País de publicação:England
Idioma:eng
Resumo:Stomata modulate the exchange of water and CO between plant and atmosphere. Although stomatal density is known to affect CO diffusion into the leaf and thus photosynthetic rate, the effect of stomatal density and patterning on CO assimilation is not fully understood. We used wild types Col-0 and C24 and stomatal mutants sdd1-1 and tmm1 of Arabidopsis thaliana, differing in stomatal density and pattern, to study the effects of these variations on both stomatal and mesophyll conductance and CO assimilation rate. Anatomical parameters of stomata, leaf temperature and carbon isotope discrimination were also assessed. Our results indicate that increased stomatal density enhanced stomatal conductance in sdd1-1 plants, with no effect on photosynthesis, due to both unchanged photosynthetic capacity and decreased mesophyll conductance. Clustering (abnormal patterning formed by clusters of two or more stomata) and a highly unequal distribution of stomata between the adaxial and abaxial leaf sides in tmm1 mutants also had no effect on photosynthesis. Except at very high stomatal densities, stomatal conductance and water loss were proportional to stomatal density. Stomatal formation in clusters reduced stomatal dynamics and their operational range as well as the efficiency of CO transport.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Arabidopsis Proteins); 0 (Carbon Isotopes); 142M471B3J (Carbon Dioxide)



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