elemental uptake
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2021 ◽  
Author(s):  
Danieli Guerra ◽  
Elisa Oliveira ◽  
Amanda Sonntag ◽  
Patrícia Sbaraine ◽  
André Fay ◽  
...  

Abstract In this work, an intercomparison of sensitization effects produced by gold (GNP) and dextran-coated iron oxide (SPION-DX) nanoparticles in M059J and U87 human glioblastoma cells was performed using 6MV-photons. Three variables were mapped: the nanoparticle material, treatment concentration, and cell radiosensitivity. For U87, GNP treatments resulted in high sensitization enhancement ratios (SER10% up to 2.04). More modest effects were induced by SPION-DX, but still significant reductions in survival were achieved (maximum SER10%=1.61). For the radiosensitive M059J, sensitization by both NPs was poor. SER10% increased with the degree of elemental uptake in the cells, but not necessarily with treatment concentration. For GNP, where exposure concentration and elemental uptake were found to be proportional, SER10% increased linearly with concentration in both cell lines. For SPION-DX, saturation of sensitization enhancement and metal uptake occurred at high exposures. Fold change in the α/β ratios extracted from survival curves are reduced by the presence of SPION-DX but strongly increased by GNPs, suggesting that sensitization by GNPs occurs mainly via promotion of lethal damage, while for SPION-DX repairable damage dominates. The NPs were more effective in eliminating the radioresistant glioblastoma cells, an interesting finding, as resistant cells are key targets to improve treatment outcome.


2021 ◽  
Author(s):  
Andre Baldermann ◽  
Santanu Banerjee ◽  
György Czuppon ◽  
Martin Dietzel ◽  
Juraj Farkas ◽  
...  

Abstract Retrograde clay mineral reactions (i.e., reverse weathering), including glauconite formation, are first-order controls on element (re)cycling vs sequestration in modern and ancient marine sediments. Here, we report substantial K–Mg–Fe sequestration by glauconite formation in shallow marine settings from the Triassic to the Holocene, averaging 4 ± 3 mmol K·cm−²·kyr− 1, 4 ± 2 mmol Mg·cm−²·kyr− 1 and 10 ± 6 mmol Fe·cm−²·kyr− 1, which is ~ 2 orders of magnitude higher compared to deep-sea settings. Upscaling of glauconite abundances in shallow-water (< 200 m) environments predicts a global K–Mg–Fe uptake of ~ 0.05–0.06 Tmol K·yr− 1, ~ 0.04–0.06 Tmol Mg·yr− 1 and ~ 0.11–0.14 Tmol Fe·yr− 1. We conclude that authigenic clay elemental uptake had a large impact on the global marine K, Mg and Fe cycles throughout Earth`s history, in particular during ‘greenhouse’ periods with sea level highstand. Quantifying authigenic clay formation is key for better understanding past and present geochemical cycling in marine sediments.


2021 ◽  
Vol 13 (17) ◽  
pp. 9784
Author(s):  
Miroslava Mitrović ◽  
Tijana Blanusa ◽  
Marija Pavlović ◽  
Dragana Pavlović ◽  
Olga Kostić ◽  
...  

Optimal uptake of micronutrients (B, Cu, Fe, Mn, and Zn) and managing the potentially toxic elements (PTEs) (Co, Cr, Ni, Pb, and Sr) in the ranges not detrimental to plant function may be linked to improving plants’ healthy growth and the ability to provide ecosystem services. We investigated concentrations, mobility, and potential availability of potentially toxic elements (PTEs) in soil samples from polluted and non-polluted municipal parks in Reading (UK) and Belgrade (Serbia) and their impact on elemental concentrations in Tilia leaves. We aimed to identify common limiting factors potentially affecting the growth/healthy function of this widely-used tree species. Levels of all elements in soil were below limits established by the directive of European Communities, except for Ni at Belgrade sites. Content of Co, Cr, Cu, Fe, Ni, Pb, and Zn in soluble fraction at all locations was <10%, indicating low mobility; B showed moderate mobility (11.1–20.7%), Mn (6.5–55.6%), and Sr—high (44–76.3%). Principal Component Analysis of Tilia leaf tissues showed a different capacity for uptake/accumulation of PTEs in different locations. Findings indicate the complexity of local edaphic influences on plants’ elemental uptake and the risk of those leading to deficiency of important micronutrients, which may impede trees’ function and thus the ability to optimally provide ecosystem services.


Author(s):  
Qingxu Ma ◽  
Paul W. Hill ◽  
David R. Chadwick ◽  
Lianghuan Wu ◽  
Davey L. Jones

AbstractPlant S deficiency is common, but the role of S-containing amino acids such as cysteine in plant S uptake is unknown. We applied 14C-, 35S-, 13C-, and 15N-labelled cysteine to wheat and oilseed rape rhizospheres and traced the plants’ elemental uptake. Both plants absorbed 0.37–0.81% of intact cysteine after 6 h with no further increase after 24 h. They absorbed 1.6–11.5% 35S and 12.3–7.6% 15N from cysteine after 24 h and utilised SO42− as their main S source (75.5–86.4%). Added and naturally occurring cysteine-S contributed 5.6 and 1.1% of total S uptake by wheat and oilseed rape, respectively. Cysteine and inorganic S derived from cysteine contributed 24.5 and 13.6% of uptake for wheat and oilseed rape, respectively, after 24 h. Oilseed rape absorbed ~10-fold more S from cysteine and SO42− than did wheat. The highest absorption of free cysteine should be in the organic-rich soil patches. Soil microorganisms rapidly decomposed cysteine (t1/2 = 1.37 h), and roots absorbed mineralised inorganic N and S. After 15 min, 11.7–14.3% of the 35S-cysteine was retained in the microbial biomass, while 30.2–36.7% of the SO42− was released, suggesting that rapid microbial S immobilisation occurs after cysteine addition. Plants acquire N and S from cysteine via unidirectional soil-to-root nutrient flow, and cysteine is an important S source for plants.


2021 ◽  
Author(s):  
Pablo Higueras ◽  
Francisco-Jesus Garcia-Navarro ◽  
Marta-Maria Moreno-Valencia ◽  
Jose-Maria Esbrí ◽  
Jesús Garcia-Pradas ◽  
...  

&lt;p&gt;Castilla-La Mancha (CLM), located in South-Central Spain, is a region of some 80,000 Km&lt;sup&gt;2&lt;/sup&gt; centered in agricultural and livestock activity, being the first major producer of wine and second of olive oil in Spain (after Andaluc&amp;#237;a), and an important producer of sheep cheese and lamb meal. Besides, the region has supported an important metallic mining activity, including mercury and base metals; these mines, most of them located in the West of the region, are actually closed, but still an important number of industrial minerals (limestone and gypsum as most important, but also other salts and clays varieties) are active in the central and Eastern part of the region.&lt;/p&gt;&lt;p&gt;Up to date, CLM does not have generic reference levels (GRLs) for elemental concentrations; neither it has a distribution map of potentially toxic elements (PTEs) along its territory. These are actually basic needs for regions with economy based on agriculture and livestock.&lt;/p&gt;&lt;p&gt;The project BiGeoQCLM, funded by Consejer&amp;#237;a de Educaci&amp;#243;n, Cultura y Deportes, Regional Government of CLM, is aimed to obtain a portrait of the distribution of elements in the whole region; the information to collect is aimed to three main objectives: (1): characterize the elemental distribution, including the estimation of GRLs, and the delimitation of the distribution of elements, and in particular of PTEs in the mining areas; together with this, the characterization of the soils of the region, including the distribution of their pedological parameters (2): characterize the soil-to-organisms interactions, including microbiology (through enzymatic activity) and plants (through characterization of elemental plant uptake; and (3): the characterization of the elemental uptake by plants aimed to assess the origin of wine, including the isotopic footprint of soils and wines with certified origin.&lt;/p&gt;&lt;p&gt;The project is in its second year (of three) of development and the work in activity is still mostly related with the field and laboratory work. However, some results are available, and are being presented in other communications of this Conference. In particular, the activity in the South-West of the region, which was the richest in metals-based mining, has been boosted with the starting of the AUREOLE project, funded by European ERA-MIN program, and aimed to find new criteria for the research of Sb and related elements, as well as with the environmental concerns related with the mining of such elements.&lt;/p&gt;&lt;p&gt;This study is being funded by Consejer&amp;#237;a de Educaci&amp;#243;n, Cultura y Deportes, JCCM (SBPLY/17/180501/000273), with the additional support of project PCI2019-103779, Spanish Ministry of Science and Innovation.&lt;/p&gt;


Author(s):  
Marcio Yukihiro Kohatsu ◽  
Milena Trevisan Pelegrino ◽  
Lucilena Rebelo Monteiro ◽  
Bruna Moreira Freire ◽  
Rodrigo Mendes Pereira ◽  
...  

2020 ◽  
Vol 646 ◽  
pp. 109-125
Author(s):  
LM Cavole ◽  
JA Miller ◽  
P Salinas-de-León ◽  
O Aburto-Oropeza ◽  
JR Marin Jarrin ◽  
...  

The effect of extrinsic (environmentally based) and intrinsic (physiologically based) controls on otolith elemental signatures remains poorly understood. We evaluated the relative importance of both extrinsic and intrinsic factors using juvenile fish in Eastern Tropical Pacific (ETP) mangroves. To assess extrinsic influences, we compared the cohabiting yellow snapper Lutjanus argentiventris and sailfin grouper Mycteroperca olfax from the Galápagos Archipelago. To evaluate intrinsic influences, we compared yellow snapper from the Gulf of California (Mexico) and the Galápagos Archipelago (Ecuador). The 2 cohabiting species in the Galápagos exhibited very similar otolith elemental signatures, with no significant differences observed for Li, Cu, Mg, Mn, Rb, and Sr (univariate ANOVAs, p > 0.05), and a small separation achieved between these species (ANOSIM test, R = 0.01, p = 0.038). The yellow snappers from Galápagos and the Gulf of California exhibited distinct elemental signatures increasing from Rb, Cu, Mn, Sr, Li to Ba (univariate ANOVAs, p < 0.05), with a large separation between them (ANOSIM test, R = 0.55, p = 0.001). The present study suggests that extrinsic factors (e.g. water chemistry, temperature, salinity) can be more important than intrinsic factors (e.g. physiology, growth rates, genetics) for influencing elemental uptake in the otoliths of juveniles from mangrove waters. However, improved understanding of factors influencing elemental incorporation is still needed to ensure accurate interpretation of field data, especially in dynamic oceanographic systems, which is the case for both the Gulf of California and the Galápagos Archipelago.


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