Short-term tissue decomposition alters stable isotope values and C:N ratio, but does not change relationships between lipid content, C:N ratio, and Δδ13C in marine animals

Numerous researchers have attempted to find suitable proxies for the lipid content of fishes. Owing to the high carbon content of lipids, C:N ratios have been used as a predictor of lipid content both for the purposes of quantifying condition and for stable isotope analyses. Here we examine the utility of C:N ratios for predicting the lipid content within and among populations, and to validate commonly used published percent lipid – C:N ratio models. No common percent lipid – C:N ratio model was found to apply; instead, population-specific influences on lipid content were observed. Published lipid prediction models significantly underestimated lipid content, and often had worse prediction error than the error obtained by using measured mean lipids as the prediction for all samples. Maximum prediction error by population ranged from a low of 50.7% to a high of 65.0%. Our results provide no support for the idea that there is a predictable relationship between bulk C:N ratios and lipid content. We recommend that sample-specific relationships be developed in situations where lipid prediction is needed, rather than relying on published models.

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Arsenic speciation in food chains from mid-Atlantic hydrothermal vents

Environmental Chemistry ◽

10.1071/en11134 ◽

2012 ◽

Vol 9 (2) ◽

pp. 130 ◽

Cited By ~ 21

Author(s):

Vivien F. Taylor ◽

Brian P. Jackson ◽

Matthew R. Siegfried ◽

Jana Navratilova ◽

Kevin A. Francesconi ◽

...

Keyword(s):

Stable Isotope ◽

Deep Sea ◽

Hydrothermal Vents ◽

Arsenic Speciation ◽

Inorganic Arsenic ◽

Food Sources ◽

Arsenic Compounds ◽

Marine Animals ◽

Δ13c And Δ15n ◽

Organic Arsenic

Environmental contextArsenic occurs in marine organisms at high levels and in many chemical forms. A common explanation of this phenomenon is that algae play the central role in accumulating arsenic by producing arsenic-containing sugars that are then converted into simpler organic arsenic compounds found in fish and other marine animals. We show that animals in deep-sea vent ecosystems, which are uninhabited by algae, contain the same organic arsenic compounds as do pelagic animals, indicating that algae are not the only source of these compounds. AbstractArsenic concentration and speciation were determined in benthic fauna collected from the Mid-Atlantic Ridge hydrothermal vents. The shrimp species, Rimicaris exoculata, the vent chimney-dwelling mussel, Bathymodiolus azoricus, Branchipolynoe seepensis, a commensal worm of B. azoricus and the gastropod Peltospira smaragdina showed variations in As concentration and in stable isotope (δ13C and δ15N) signature between species, suggesting different sources of As uptake. Arsenic speciation showed arsenobetaine to be the dominant species in R. exoculata, whereas in B. azoricus and B. seepensis arsenosugars were most abundant, although arsenobetaine, dimethylarsinate and inorganic arsenic were also observed, along with several unidentified species. Scrape samples from outside the vent chimneys covered with microbial mat, which is a presumed food source for many vent organisms, contained high levels of total As, but organic species were not detectable. The formation of arsenosugars in pelagic environments is typically attributed to marine algae, and the pathway to arsenobetaine is still unknown. The occurrence of arsenosugars and arsenobetaine in these deep sea organisms, where primary production is chemolithoautotrophic and stable isotope analyses indicate food sources are of vent origin, suggests that organic arsenicals can occur in a foodweb without algae or other photosynthetic life.

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Folate bioavailability from foods rich in folates assessed in a short term human study using stable isotope dilution assays

Food & Function ◽

10.1039/c4fo00658e ◽

2015 ◽

Vol 6 (1) ◽

pp. 241-247 ◽

Cited By ~ 18

Author(s):

Sabine Mönch ◽

Michael Netzel ◽

Gabriele Netzel ◽

Undine Ott ◽

Thomas Frank ◽

...

Keyword(s):

Stable Isotope ◽

Isotope Dilution ◽

Human Study ◽

Short Term ◽

Standard Definition ◽

Stable Isotope Dilution ◽

Stable Isotope Dilution Assays ◽

Folate Bioavailability ◽

Definition Of ◽

Different Sources

Different sources of folate may have different bioavailability and hence may impact the standard definition of folate equivalents.

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Behavioural Stress Propagation in Benthic Invertebrates Caused by Acute pH Drop-Induced Metabolites

Frontiers in Marine Science ◽

10.3389/fmars.2021.773870 ◽

2021 ◽

Vol 8 ◽

Author(s):

Lauric Feugere ◽

Lauren Angell ◽

James Fagents ◽

Rebecca Nightingale ◽

Kirsty Rowland ◽

...

Keyword(s):

Chemical Communication ◽

Stress Responses ◽

Benthic Invertebrates ◽

Interspecific Interactions ◽

Hermit Crabs ◽

Sea Bream ◽

Short Term ◽

Marine Animals ◽

Regular Control ◽

Stress Metabolites

Studies on pH stress in marine animals typically focus on direct or species-specific aspects. We here test the hypothesis that a drop to pH = 7.6 indirectly affects the intra- and interspecific interactions of benthic invertebrates by means of chemical communication. We recorded fitness-relevant behaviours of small hermit crabs Diogenes pugilator, green shore crabs Carcinus maenas, and harbour ragworms Hediste diversicolor in response to short-term pH drop, and to putative stress metabolites released by conspecifics or gilt-head sea bream Sparus aurata during 30 min of acute pH drop. Not only did acute pH drop itself impair time to find a food cue in small hermit crabs and burrowing in harbour ragworms, but similar effects were observed under exposure to pH drop-induced stress metabolites. Stress metabolites from S. aurata, but not its regular control metabolites, also induced avoidance responses in all recipient species. Here, we confirm that a short-term abrupt pH drop, an abiotic stressor, has the capacity to trigger the release of metabolites which induce behavioural responses in conspecific and heterospecific individuals, which can be interpreted as a behavioural cost. Our findings that stress responses can be indirectly propagated through means of chemical communication warrant further research to confirm the effect size of the behavioural impairments caused by stress metabolites and to characterise their chemical nature.

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Short-Term Hyperinsulinemia and Hyperglycemia Increase Myocardial Lipid Content in Normal Subjects

Diabetes ◽

10.2337/db11-1275 ◽

2012 ◽

Vol 61 (5) ◽

pp. 1210-1216 ◽

Cited By ~ 37

Author(s):

Yvonne Winhofer ◽

Martin Krššák ◽

Draženka Janković ◽

Christian-Heinz Anderwald ◽

Gert Reiter ◽

...

Keyword(s):

Lipid Content ◽

Normal Subjects ◽

Short Term

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Changes in Soil Properties and Productivity under Different Tillage Practices and Wheat Genotypes: A Short-Term Study in Iran

Sustainability ◽

10.3390/su10093273 ◽

2018 ◽

Vol 10 (9) ◽

pp. 3273 ◽

Cited By ~ 9

Author(s):

Shokoofeh Khorami ◽

Seyed Kazemeini ◽

Sadegh Afzalinia ◽

Mahesh Gathala

Keyword(s):

Soil Properties ◽

Block Design ◽

Water Productivity ◽

C:N Ratio ◽

Wheat Yield ◽

Water Infiltration ◽

Reduced Tillage ◽

Short Term ◽

Wheat Genotypes ◽

Tillage Practices

Natural resources are the most limiting factors for sustainable agriculture in Iran. Traditional practices are intensive tillage that leads to a negative impact on crop productivity and soil properties. Conservation agriculture including tillage reductions, better agronomy, and improved varieties, showed encouraging results. The goal of this study was to test combined effect of tillage practices and wheat (Triticum aestivum L.) genotypes on soil properties as well as crop and water productivity. The experiment was conducted at Zarghan, Fars, Iran during 2014–2016. Experimental treatments were three-tillage practices—conventional tillage (CT), reduced tillage (RT), and no tillage (NT)—and four wheat genotypes were randomized in the main and subplots, respectively using split-plot randomized complete block design with three replications. Results showed NT had higher soil bulk density at surface soil, thereby lower cumulative water infiltration. The lowest soil organic carbon and total nitrogen were obtained under CT that led to the highest C:N ratio. Reduced tillage produced higher wheat yield and maize (Zea mays L.) biomass. Maximum irrigation water was applied under CT, which leads lower water productivity. The findings are based on short-term results, but it is important to evaluate medium- and long-term effects on soil properties, crop yields and water use in future.

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Short-Term Stable Isotope Probing of Proteins Reveals Taxa Incorporating Inorganic Carbon in a Hot Spring Microbial Mat

Applied and Environmental Microbiology ◽

10.1128/aem.01829-19 ◽

2020 ◽

Vol 86 (7) ◽

Cited By ~ 1

Author(s):

Laurey Steinke ◽

Gordon W. Slysz ◽

Mary S. Lipton ◽

Christian Klatt ◽

James J. Moran ◽

...

Keyword(s):

Stable Isotope ◽

Inorganic Carbon ◽

Microbial Mats ◽

Carbon Fixation ◽

Hot Springs ◽

Hot Spring ◽

Stable Isotope Probing ◽

Short Term ◽

Low Light ◽

Assembly Sequences

ABSTRACT The upper green layer of the chlorophototrophic microbial mats associated with the alkaline siliceous hot springs of Yellowstone National Park consists of oxygenic cyanobacteria (Synechococcus spp.), anoxygenic Roseiflexus spp., and several other anoxygenic chlorophototrophs. Synechococcus spp. are believed to be the main fixers of inorganic carbon (Ci), but some evidence suggests that Roseiflexus spp. also contribute to inorganic carbon fixation during low-light, anoxic morning periods. Contributions of other phototrophic taxa have not been investigated. In order to follow the pathway of Ci incorporation into different taxa, mat samples were incubated with [13C]bicarbonate for 3 h during the early-morning, low-light anoxic period. Extracted proteins were treated with trypsin and analyzed by mass spectrometry, leading to peptide identifications and peptide isotopic profile signatures containing evidence of 13C label incorporation. A total of 25,483 peptides, corresponding to 7,221 proteins, were identified from spectral features and associated with mat taxa by comparison to metagenomic assembly sequences. A total of 1,417 peptides, derived from 720 proteins, were detectably labeled with 13C. Most 13C-labeled peptides were derived from proteins of Synechococcus spp. and Roseiflexus spp. Chaperones and proteins of carbohydrate metabolism were most abundantly labeled. Proteins involved in photosynthesis, Ci fixation, and N2 fixation were also labeled in Synechococcus spp. Importantly, most proteins of the 3-hydroxypropionate bi-cycle for Ci fixation in Roseiflexus spp. were labeled, establishing that members of this taxocene contribute to Ci fixation. Other taxa showed much lower [13C]bicarbonate incorporation. IMPORTANCE Yellowstone hot spring mats have been studied as natural models for understanding microbial community ecology and as modern analogs of stromatolites, the earliest community fossils on Earth. Stable-isotope probing of proteins (Pro-SIP) permitted short-term interrogation of the taxa that are involved in the important process of light-driven Ci fixation in this highly active community and will be useful in linking other metabolic processes to mat taxa. Here, evidence is presented that Roseiflexus spp., which use the 3-hydroxypropionate bi-cycle, are active in Ci fixation. Because this pathway imparts a lower degree of selection of isotopically heavy Ci than does the Calvin-Benson-Bassham cycle, the results suggest a mechanism to explain why the natural abundance of 13C in mat biomass is greater than expected if only the latter pathway were involved. Understanding how mat community members influence the 13C/12C ratios of mat biomass will help geochemists interpret the 13C/12C ratios of organic carbon in the fossil record.

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Changes in Plaque Lipid Content After Short-Term Intensive Versus Standard Statin Therapy

Journal of the American College of Cardiology ◽

10.1016/j.jacc.2013.03.058 ◽

2013 ◽

Vol 62 (1) ◽

pp. 21-29 ◽

Cited By ~ 124

Author(s):

Annapoorna S. Kini ◽

Usman Baber ◽

Jason C. Kovacic ◽

Atul Limaye ◽

Ziad A. Ali ◽

...

Keyword(s):

Statin Therapy ◽

Lipid Content ◽

Short Term

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Short-Term Nitrogen Addition Does Not Significantly Alter the Effects of Seasonal Drought on Leaf Functional Traits in Machilus pauhoi Kanehira Seedlings

Forests ◽

10.3390/f10020078 ◽

2019 ◽

Vol 10 (2) ◽

pp. 78 ◽

Cited By ~ 1

Author(s):

Hua Yu ◽

Dongliang Cheng ◽

Baoyin Li ◽

Chaobin Xu ◽

Zhongrui Zhang ◽

...

Keyword(s):

Functional Traits ◽

C:N Ratio ◽

Leaf Traits ◽

N Deposition ◽

Interactive Effects ◽

N Addition ◽

Subtropical China ◽

Short Term ◽

Leaf Functional Traits ◽

Seasonal Drought

Research Highlights: Short-term nitrogen (N) addition did not significantly alter the effects of seasonal drought on the leaf functional traits in Machilus pauhoi Kanehira seedlings in N-rich subtropical China. Background and Objectives: Seasonal drought and N deposition are major drivers of global environmental change that affect plant growth and ecosystem function in subtropical China. However, no consensus has been reached on the interactive effects of these two drivers. Materials and Methods: We conducted a full-factorial experiment to analyze the single and combined effects of seasonal drought and short-term N addition on chemical, morphological and physiological traits of M. pauhoi seedlings. Results: Seasonal drought (40% of soil field capacity) had significant negative effects on the leaf N concentrations (LNC), phosphorus (P) concentrations (LPC), leaf thickness (LT), net photosynthetic rate (A), transpiration rate (E), stomatal conductance (Gs), and predawn leaf water potential (ψPD), and significant positive effects on the carbon:N (C:N) ratio and specific leaf area (SLA). Short-term N addition (50 kg N·hm−2·year−1 and 100 kg N·hm−2·year−1) tended to decrease the C:N ratio and enhance leaf nutrient, growth, and photosynthetic performance because of increased LNC, LPC, LT, leaf area (LA), SLA, A, E, and ψPD; however, it only had significant effects on LT and Gs. No significant interactive effects on leaf traits were detected. Seasonal drought, short-term N addition, and their interactions had significant effects on soil properties. The soil total C (STC), nitrate N (NO3−-N) and soil total N (STN) concentrations were the main factors that affected the leaf traits. Conclusions: Seasonal drought had a stronger effect on M. pauhoi seedling leaf traits than short-term N deposition, indicating that the interaction between seasonal drought and short-term N deposition may have an additive effecton M. pauhoi seedling growth in N-rich subtropical China.

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