Scientific Literature

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A method based on asymmetric flow field flow fractionation hyphenated to inductively coupled plasma mass spectrometry for the monitoring of platinum nanoparticles in water samples

Date: 2021
Authors: Sánchez-Cachero, A;López-Sanz, S;Fariñas, N;Ríos, ;Martín-Doimeadios, R;
References: Talanta 222 121513
Keywords/Products: ICP;ICP-MS;Meinhard;Thermo;
An analytical methodology based on asymmetric flow field flow fractionation hyphenated to inductively coupled plasma mass spectrometry (AF4-ICP-MS) has been developed for monitoring citrate coated platinum nanoparticles (PtNPs) of different sizes (5, 30, and 50 nm) in water samples. Several factors have been optimized, such as carrier composition, AF4 separation program, focusing step or cross flow values. Under the optimum conditions, PtNPs can be fractionated in about 30 min in a single run with quantitative recoveries of the membrane (100 ± 7%, n = 5). The optimized method has been successfully applied to study transformations, not only in size but also surface modifications, of PtNPs in synthetic and natural water samples over time. The effect of organic matter was specifically studied, and it was found to be a critical parameter. The analytical strategy followed in this work can be very useful to develop further environmental studies involving PtNPs.

Ammonium acetate as a novel buffer for highly selective robust urinary HPLC-ICP-MS arsenic speciation methodology

Date: 2021
Authors: Rodríguez, P;Martín-Aranda, R;López Colón, J;de Mendoza, J;
References: Talanta 221 121494
Keywords/Products: ELAN;ICP;ICP-MS;Meinhard;
Ammonium acetate is employed in order to develop a novel HPLC-ICP-MS arsenic speciation methodology applicable to six arsenic species, i.e, AC, AB, AsIII, AsV, DMA and MMA. The most predominant species in the toxicological field are covered in a 30-min chromatogram with reproducible and repeatability peak area ratio. Moreover, typical problems from traditional methods are sorted out by using a robust, high-selective and 75ArCl+ interference-free methodology. Chromatographic and detector optimization ensures low LOQs for each species with acceptable precision and accuracy values obtained using four urinary arsenic speciation PTS enabling to be useful for sub ng mL?1 arsenic exposure assessments.

Characterization and Neuroprotection Potential of Seleno-Polymannuronate

Date: 2020
Authors: Bi, D;Li, X;Li, T;Li, X;Lin, Z;Yao, L;Li, H;Xu, H;Hu, Z;Zhang, Z;Liu, Q;Xu, X;
References: Front Pharmacol 11 21
Keywords/Products: Meinhard;
Seleno-polymannuronate (Se-PM) was prepared from alginate-derived polymannuronate (PM) through a sulfation followed by a selenylation replacement reaction. The organic selenium content of Se-PM was 437.25 µg/g and its average molecular weight was 2.36 kDa. The neuroprotection effect of Se-PM and corresponding molecular mechanisms were investigated. Our results showed that, comparing to both sulfated PM (S-PM) and PM, Se-PM remarkably inhibited the aggregation of Aβ1-42 oligomer in vitro and significantly reduced the APP and BACE1 protein expression in N2a-sw cells, highlighting the critical function of the selenium presented in Se-PM. Moreover, Se-PM decreased the expression of cytochrome c and the ratio of Bax to Bcl-2, and enhanced the mitochondrial membrane potential in N2a-sw cells. These results suggested that Se-PM treatment can markedly inhibit N2a-sw cell apoptosis and promote N2a-sw cell survival and that Se-PM might be a potential therapeutic agent for the prevention of neurodegeneration owing to its remarkable neuroprotection effect.

Petrogenesis of ca. 830 Ma Lushan bimodal volcanic rocks at the southeastern margin of the Yangtze Block, South China: Implications for asthenospheric upwelling and reworking of juvenile crust

Date: 2020
Authors: Cheng, J;Li, W;Wang, X;Li, X;Pang, C;
References: Precambrian Research 342 105673
Keywords/Products: Glass Nebulizer;ICP;Meinhard;
Neoproterozoic bimodal volcanic rocks are widespread in the South China Block and provide information on crust-mantle interaction, the thermal and chemical status of the deep mantle, and the growth and reworking of continental crust. In this paper, we present sensitive high-resolution ion microprobe (SHRIMP) zircon U-Pb ages and whole-rock geochemistry for the Lushan bimodal volcanic rocks in northern Jiangxi Province, South China Block. Our SHRIMP dating indicates that the Lushan bimodal volcanic rocks were erupted at 835-820 Ma. The least-evolved mafic rocks have high εNd(t) (+8.3) and "arc-like" Nb/La and Nb/Th ratios, thier derivation from fluid-modified depleted mantle. The melts that formed these mafic rocks underwent fractional crystallization involving mineral assemblages of olivine + plagioclase → clinopyroxene + plagioclase at MgO < ˜6.0 wt% → clinopyroxene + plagioclase + Fe-Ti oxides at MgO < ~5 wt%, and crustal contamination during ascent. εNd(t) values of the felsic rocks (-1.39 to +1.64) differ from those of the contemporaneous mafic rocks (εNd(t) = +2.19 to +8.33), arguing against an origin by fractional crystallization of the mafic magmas. The felsic rocks are characterized by high (10,000×Ga)/Al ratios and enrichment in high-field-strength elements (Nb + Ce + Y + Zr), low P2O5 contents (<0.1%), a peraluminous nature (A/CNK > 1.2), and a lack of typical alkaline mafic minerals, suggesting that they are aluminous A-type granitic rocks. Therefore, the felsic rocks probably originated from partial melting of fertile felsic meta-igneous rocks in the shallow crust. The ~830 Ma bimodal volcanic rocks indicate Neoproterozoic rift-related extensional thinning of the crust associated with asthenospheric upwelling along the southeastern margin of the South China Block. The geochemistry of the mafic rocks indicates two distinct mantle sources beneath the southeastern margin of the Yangtze Block at ca. 830 Ma: a depleted asthenospheric mantle with εNd(t) > +8, and an enriched mantle plume source with εNd(t) < 0. The rift-related asthenospheric mantle upwelling associated with mantle-plume-related mafic magmatism enhanced the geothermal gradient of the crust and conducted mantle heat into it, ultimately resulting in reworking of 860-830 Ma juvenile crust at various levels.

Spatially resolved Stoichiometry Determination of Li7La3Zr2O12 Solid-state Electrolytes using LA-ICP-OES

Date: 2020
Authors: Smetaczek, S;Bonta, M;Wachter-Welzl, A;Taibl, S;Wagner, R;Rettenwander, D;Fleig, J;Limbeck, A;
References: J. Anal. At. Spectrom. 1 1
Keywords/Products: ICP;ICP-OES;Meinhard;Quartz Nebulizer;sample introduction;
Cubic Li7La3Zr2O12 (LLZO) garnets are among the most promising solid-state electrolytes for next-generation Li batteries. However, despite intensive research in recent years, little effort is spent on proper chemical analysis of the material. For reliable LLZO investigation, knowledge about the exact chemical composition, especially the Li content, is of uttermost importance. Herein, we present a method for the laterally resolved stoichiometry determination of Al stabilized LLZO (Li7-3xAlxLa3Zr2O12) using LA-ICP-OES. To ensure reliable signal quantification, matrix-matched standards are prepared and carefully characterized using sample digestion and liquid ICP-OES measurement. An internal standard-independent calibration strategy based on 100 m% normalization is applied, enabling the quantification of all cations within the material. By comparing the obtained high-precision LA-ICP-OES calibrations with analog LA-ICP-MS measurements, it is shown that ICP-OES is the superior choice for the analysis of Li. The developed method is applied to record quantitative distribution images of an Al stabilized LLZO pellet, revealing macroscopic stoichiometry variations within the sample. To verify the analysis, the average stoichiometry obtained by the LA measurements is compared with the bulk composition determined via liquid ICP-OES analysis after sample fusion. The obtained values show excellent agreement, confirming the accuracy of the developed method.

Use of a mixed argon-hydrogen-tetrafluoromethane carrier gas for the analysis of nickel materials by electrothermal vaporization coupled to inductively coupled plasma optical emission spectrometry

Date: 2020
Authors: Harrington, K;Al Hejami, A;Beauchemin, D;
References: J. Anal. At. Spectrom. 35 461-466
Keywords/Products: ICPOES;Meinhard;
Electrothermal vaporization (ETV) coupled to inductively coupled plasma optical emission spectrometry (ICPOES) was used to directly determine minor and trace elements in nickel (Ni) foam samples. In addition to 9 mL min-1 CF4 reaction gas, 20 mL min-1 H2 was added to the carrier gas to further enhance the volatility of analytes. Moreover, 45 mL min-1 N2 was introduced into the central channel of the plasma via a sheathing device to improve plasma robustness, sensitivity and detection limit. The ETV program included a pyrolysis step (400 °C, 20 s), a cooling step (21 °C, 15 s), a vaporization step (2300 °C, 30 s), and a cooling step (21 °C, 20 s). The Ar 415.859 nm emission line was systematically used for point-by-point internal standardization, to compensate for sample loading effects on the plasma, before computing the peak area of the transient signal observed for each analyte during the vaporization and final cooling steps (between 45-90 s). External calibration was carried out using increasing amounts of NIST 2710 (Montana soil) standard reference material. The measured concentrations of Cd, Cr, Mn, Mo, Pb, V, and Zn agree with those obtained by pneumatic nebulization ICPOES after digestion with HNO3. This method offers a fast and accurate determination of minor and trace elements in Ni foam without sample preparation.

Assessing the harmfulness of high-salinity oilfield-produced water related to trace metals using vortex-assisted dispersive liquid-liquid microextraction combined with inductively coupled plasma optical emission spectrometry

Date: 2020
Authors: Guedes, L;Braz, B;Freire, A;Santelli, R;
References: Microchemical Journal 155 104714
Keywords/Products: ICP;ICP-MS;Meinhard;Quartz Nebulizer;Thermo;
A method for quantifying trace levels of cadmium, lead, nickel and cobalt in high-salinity produced water (salinities up to 168) using vortex-assisted dispersive liquid-liquid microextraction (VA DLLME) combined with inductively coupled plasma optical emission spectrometry (ICP OES) was developed. Diethyldithiocarbamate (DDTC) was used as chelating agent, and complexes were extracted adding methanol (dispersive solvent) and carbon tetrachloride (extraction solvent) to aqueous samples. The organic (CCl4) sedimented phase was separated and evaporated, and the solubilized residue was analysed by ICP OES. The extraction and quantification parameters were optimized by univariate and Doehlert strategies.

Egg white hydrolysate prevents reproductive impairments induced by cadmium in rats

Date: 2020
Authors: Pinheiro, J;Martinez, C;Moraes, P;Stasiaki, J;Trost, M;Vassallo, D;Barbosa, F;Pecanha, F;Cibin, F;Miguel, M;Wiggers, G;
References: Journal of Functional Foods 67 103823
Keywords/Products: ICP;ICP-MS;Meinhard;sample introduction;
Here, we investigated the ability of an egg white hydrolysate (EWH) to counteract the reproductive toxic effects induced by Cd in rats. 3-month-old male Wistar rats were treated for 14 days: (a) Untreated group (distilled water i.p.); (b) Cd group (CdCl2 at 1 mg/kg body weight i.p.); (c) EWH group (1 g/kg body weight/day per gavage); (d) CdEWH group (CdCl2 with EWH). Cd exposure was able to be accumulated in testis and epididymis, increasing oxidative stress and compromising sperm quality and daily sperm production. Co-treatment with EWH prevented increased deposition of Cd in testis (Untreated: 0.04 ± 0.02; Cd: 4.68 ± 1.03*; EWH: 0.01 ± 0.00; CdEWH: 1.85 ± 0.25# µg Cd/g dry tissue p 

Enterococcus faecalis manganese exporter MntE alleviates manganese toxicity and is required for mouse gastrointestinal colonization

Date: 2020
Authors: Lam, LN;Wong, JJ;Chong, KKL;Kline, KA;
References: Infect. Immun. 1 1
Keywords/Products: ELAN;ICP;ICP-MS;Meinhard;Perkin Elmer;TR-30-C3;
Bacterial pathogens encounter a variety of nutritional environments in the human host, including nutrient metal restriction and overload. Uptake of manganese (Mn) is essential for Enterococcus faecalis growth and virulence; however, it is not known how this organism prevents Mn toxicity. In this study, we examine the role of the highly conserved MntE transporter in E. faecalis Mn homeostasis and virulence. We show that inactivation of mntE results in growth restriction in the presence of excess Mn, but not other metals, demonstrating its specific role in Mn detoxification. Upon growth in the presence of excess Mn, an mntE mutant accumulates intracellular Mn, iron (Fe), and magnesium (Mg), supporting a role for MntE in Mn and Fe export, and a role for Mg in offsetting Mn toxicity. Growth of the mntE mutant in excess Fe also results in increased levels of intracellular Fe, but not Mn or Mg, providing further support for MntE in Fe efflux. Inactivation of mntE in the presence of excess iron also results in the upregulation of glycerol catabolic genes and enhanced biofilm growth, and addition of glycerol is sufficient to augment biofilm growth for both the mntE mutant and its wild type parental strain, demonstrating that glycerol availability significantly enhances biofilm formation. Finally, we show that mntE contributes to infection of the antibiotic-treated mouse gastrointestinal (GI) tract, suggesting that E. faecalis encounters excess Mn in this niche. Collectively, these findings demonstrate that the manganese exporter MntE plays a crucial role in E. faecalis metal homeostasis and virulence.

Experiments and Kinetic Modeling of Diffusion Flame Extinction of 2-Methylfuran, 2,5-Dimethylfuran, and Binary Mixtures with Isooctane

Date: 2020
Authors: Sahu, A;Markendaya, S;Badhuk, P;Ravikrishna, R;
References: Energy Fuels 34 2293-2303
Keywords/Products: Glass Nebulizer;Meinhard;POINT;
This work presents an experimental and numerical study of extinction properties of 2,5-dimethylfuran (DMF) and 2-methylfuran (MF) in counterflow diffusion flames at atmospheric pressure. The impact of addition of isooctane to the fuels is presented with two degrees of blends (25:75 and 50:50). The analysis was carried out for different levels of fuel loading ranging from 0.10 to 0.24 (volumetric) with the rest of the component being N2 as a carrier gas. Extinction limits are observed to increase with an increase in fuel loading, and the resistance to extinction follows the order MF > isooctane > DMF. Numerical predictions using the Tianjin mechanism are within 10% of the measurements for MF cases, while the Galway mechanism tends to underpredict at higher fuel loading conditions. For DMF flames, both the mechanisms perform relatively well at XF ≤ 0.14; however, they underpredict as the fuel loading is increased. Addition of isooctane to DMF led to an increase in the extinction limits at low fuel loading conditions, but the impact of blending diminished at higher fuel loading conditions. On the other hand, addition of isooctane had a minimum impact on MF flame’s extinction limit at low fuel loading conditions, while it led to a reduction in the resistance to extinction at higher fuel loadings. Numerical simulations by a mechanism proposed for the isooctane-DMF-MF blend predict similar effects of blending, however, consistently tend to underpredict at higher fuel loading conditions. Quantitative reaction path diagrams show that the H-abstraction step is the dominant fuel consumption route for near-extinction MF and DMF flames. With an increase in fuel loading, the role of C5H5 in the H-abstraction process increases in DMF/air flames. Reaction sensitivity analysis shows an increase in the importance of C5H5 kinetics in XF = 0.24 DMF flames as compared to XF = 0.14 along with the ring-opening step converting DMF to 3,4-hexadiene-2-one. In MF/air flames, the degree of change in sensitivities with fuel loading was found to be significantly low as compared to the DMF/air flames. Finally, reaction rate analysis was carried out to reveal that the slower consumption of MF causes the underprediction of the extinction strain rate by the Galway mechanism as compared to the Tianjin mechanism.

Biofortification of green bean (Phaseolus vulgaris L.) and lettuce (Lactuca sativa L.) with iodine in a plant-calcareous sandy soil system irrigated with water containing KI

Date: 2020
Authors: Dobosy, P;Kropfl, K;Ovari, M;Sandil, S;Nemeth, K;Engloner, A;Takacs, T;Zarav, G;
References: Journal of Food Composition and Analysis 88 103434
Keywords/Products: Aerosol;Meinhard;
Uptake and translocation of iodine by green bean (Phaseolus vulgaris L.) and lettus (Lactuca sativa L.) were investigated in a calcareous sandy soil-plant system. These plants were cultivated in calcareous sandy soil in presence of irrigation water with the iodine concentrations of 0.10, 0.25 and 0.50 mg/L.

Combined use of companion planting and PGPR for the assisted phytoextraction of trace metals (Zn, Pb, Cd)

Date: 2020
Authors: Konkolewska, A;Piechalak, A;Ciszewska, L;Antos-Krzeminska, N;Skrzypczak, T;Hanc, A;Sitko, K;Malkowski, E;Baralkiewicz, D;Malecka, A;
References: Environ Sci Pollut Res Int 1 1
Keywords/Products: Concentric;Concentric nebulizer;ELAN;ICP;ICP-MS;Meinhard;
Biomass production and metal accumulation in plant tissue (bioconcentration) are two critical factors limiting the phytoextraction rate. Metal translocation to aboveground organs should be accounted for as the third most important factor, as harvesting of the plant roots is usually economically disadvantageous. These three parameters could be potentially increased with the use of companion planting, a well-known agricultural technique, and inoculation with plant growth-promoting bacteria (PGPB). The aim of the study was to determine whether intercropping and inoculation with endophytic PGPB (Burkholderia phytofirmans PsJNT) can increase the efficiency of phytoextraction of Zn, Pb, and Cd.

Metallic and metalloid elements in various developmental stages of Amanita muscaria (L.) Lam

Date: 2020
Authors: Falandysz, J;Hanc, A;Baralkiewicz, D;Zhang, J;Treu, R;
References: Fungal Biol 124 174-182
Keywords/Products: Concentric;Concentric nebulizer;ELAN;ICP;ICP-MS;Meinhard;
There is growing evidence that mushrooms (fruiting bodies) can be suitable for biogeochemical prospecting for minerals and as indicators of heavy metal and radioactive contaminants in the terrestrial environment. Apart from the nutritional aspect, knowledge of accumulation dynamics and distribution of elements in fruiting bodies, from emergence to senescence, is essential as is standardization when choosing mushroom species as potential bioindicators and for monitoring purposes. We studied the effect of fruitbody developmental stage on the contents of the elements (Li, K, V, Cr, Mn, Mg, Co, Ni, Cu, Zn, As, Rb, Sr, Ag, Al, Cd, Sb, Cs, Ba, Pb, Tl and U) in the individual parts of the Amanita muscaria fruiting body. Elements such as K, Mg, Mn, Ni, Co, Cu, Zn and Se remained similar throughout all developmental stages studied, however for K, differences occurred in the values of caps and stipes, as expressed by the cap to stipe concentration quotient (index QC/S). The other elements quantified, i.e., Li, V, Cr, As, Rb, Sr, Ag, Al, Cd, Sb, Cs, Ba, Pb, Tl and U are considered as nonessential or toxic (with the exception of V in A. muscaria). Their accumulation in the fruiting bodies and their distribution between cap and stipe did not show a uniform pattern. Pb, Sb, Tl, Ba, Sr, Li, Rb and Cs decreased with increasing maturity of the fruitbodies, implying that translocation, distribution and accumulation in stipes and caps was not a continuous process, while V, Cr, As, Ag, Cd, and U remained at the same concentration, similarly to the essential elements. Our results for A. muscaria confirm that elemental distribution in different parts of fruiting bodies is variable for each element and may change during maturation. Soil properties, species specificity and the pattern of fruitbody development may all contribute to the various types of elemental distribution and suggest that the results for one species in one location may have only limited potential for generalization.

Diphenyl diselenide dietary supplementation protects against fumonisin B1-induced oxidative stress in brains of the silver catfish Rhamdia quelen

Date: 2020
Authors: Baldissera, MD;Souza, CF;da Silva, HNP;Zeppenfeld, CC;Dornelles, JL;Henn, AS;Duarte, FA;da Costa, ST;Da Silva, AS;Cunha, MA;Baldisserotto, B;
References: Comp. Biochem. Physiol. C Toxicol. Pharmacol. 231 108738
Keywords/Products: Concentric;Concentric nebulizer;ELAN;Meinhard;Perkin Elmer;
The trend toward using plant-based ingredients in aquafeeds has raised important concerns for aquaculture owing to the negative impacts of mycotoxins on fish health; with emphasis for contamination by fumonisin B1 (FB1). The brain is an important target of FB1; however, study of the pathways linked to brain damage is limited to an analysis of histopathological alterations. Reports have demonstrated the protective effects of dietary supplementation with diphenyl diselenide (Ph2Se2) in the brains of fish subjected to several environmental insults; nevertheless, its neuroprotective effects in fish fed with diets contaminated with FB1 remain unknown. Therefore, the aim of this study was to evaluate whether oxidative damage may be a pathway associated with FB1-induced neurotoxicity, as well as to evaluate whether dietary supplementation with Ph2Se2 prevents or reduces FB1-mediated brain oxidative damage in silver catfish. Brain reactive oxygen species (ROS), lipid peroxidation (LOOH) and protein carbonylation increased on day 30 post-feeding in animals that received FB1-contaminated diets compared to the control group, while brain antioxidant capacity against peroxyl radicals (ACAP) levels and catalase (CAT), glutathione peroxidase (GPx) and glutathione S-transferase (GST) activities were lower. Diphenyl diselenide dietary supplementation avoid increases in brain ROS levels, as well minimizing the augmentation of LOOH levels. Furthermore, Ph2Se2 prevented impairment of brain ACAP levels, as well as GPx and GST activities elicited by FB1-contaminated diets. These data suggest that dietary supplementation with 3 mg/kg Ph2Se2 prevented FB1-induced brain damage in silver catfish, and this protective effect occurred through avoided of excessive ROS production, as well as via prevention of brain lipid damage. Furthermore, Ph2Se2 exerted its neuroprotective effects via ameliorative effects on the enzymatic and non-enzymatic antioxidant defense systems, and may be an approach to prevent FB1-induced brain oxidative stress; however, is not an alternative to prevent the impairment on performance caused by FB1.

Low-dose lithium feeding increases the SERCA2a-to-phospholamban ratio, improving SERCA function in murine left ventricles

Date: 2020
Authors: Hamstra, SI;Kurgan, N;Baranowski, RW;Qiu, L;Watson, CJF;Messner, HN;MacPherson, REK;MacNeil, AJ;Roy, BD;Fajardo, VA;
References: Exp. Physiol. 1 1
Keywords/Products: A3 type;Concentric;Concentric nebulizer;ELAN;ICP;ICP-MS;Meinhard;
What is the central question of this study? Inhibition of glycogen synthase kinase-3 (GSK3) has been shown to improve cardiac SERCA2a function. Lithium can inhibit GSK3, but therapeutic doses used in treating bipolar disorder can have toxic effects. It has not been determined whether subtherapeutic doses of lithium can improve cardiac SERCA function. What is the main finding and its importance? Using left ventricles from wild-type mice, we found that subtherapeutic lithium feeding for 6 weeks decreased GSK3 activity and increased cardiac SERCA function compared with control-fed mice. These findings warrant the investigation of low-dose lithium feeding in preclinical models of cardiomyopathy and heart failure to determine the therapeutic benefit of GSK3 inhibition. The sarco(endo)plasmic reticulum Ca2+ -ATPase (SERCA) pump is responsible for regulating calcium (Ca2+ ) within myocytes, with SERCA2a being the dominant isoform in cardiomyocytes. Its inhibitor, phospholamban (PLN), acts by decreasing the affinity of SERCA for Ca2+ . Changes in the SERCA2a:PLN ratio can cause Ca2+ dysregulation often seen in patients with dilated cardiomyopathy and heart failure. The enzyme glycogen synthase kinase-3 (GSK3) is known to downregulate SERCA function by decreasing the SERCA2a:PLN ratio. In this study, we sought to determine whether feeding mice low-dose lithium, a natural GSK3 inhibitor, would improve left ventricular SERCA function by altering the SERCA2a:PLN ratio. To this end, male wild-type C57BL/6J mice were fed low-dose lithium via drinking water (10 mg kg-1  day-1 LiCl for 6 weeks) and left ventricles were harvested. GSK3 activity was significantly reduced in LiCl-fed versus control-fed mice. The apparent affinity of SERCA for Ca2+ was also increased (pCa50 ; control, 6.09 ± 0.03 versus LiCl, 6.26 ± 0.04, P < 0.0001) along with a 2.0-fold increase in SERCA2a:PLN ratio in LiCl-fed versus control-fed mice. These findings suggest that low-dose lithium supplementation can improve SERCA function by increasing the SERCA2a:PLN ratio. Future studies in murine preclinical models will determine whether GSK3 inhibition via low-dose lithium could be a potential therapeutic strategy for dilated cardiomyopathy and heart failure. © 2020 The Authors. Experimental Physiology © 2020 The Physiological Society.

Phenotyping of tumor infiltrating immune cells using mass-cytometry (CyTOF)

Date: 2020
Authors: Maby, P;Corneau, A;Galon, J;
References: Meth. Enzymol. 632 339-368
Keywords/Products: CyTOF;Meinhard;
The anti-tumor immune response plays a crucial role in cancer patient outcome as well as in response to the growing family of immunotherapeutic treatments. Improving patient prognostic and therapeutic management requires a better knowledge of the tumor microenvironment, for which a deep characterization of tumor-infiltrating immune populations is instrumental. Mass cytometry represents an excellent tool in tumor Immunology, as it allows the simultaneous analysis of >40 markers on single cells. In this chapter, we review challenging technical aspects of the mass cytometry phenotyping of tumor infiltrating immune cells, focusing on fresh human solid tumor samples. We first explain how to design mass cytometry experiments, then provide detailed protocols to isolate mononuclear immune cells from solid tissues and to stain them for an acquisition on a mass cytometer. We also discuss how to optimize the preparation of single immune cell samples, and how to ensure the reproducibility of data generated from distinct fresh human samples. Finally, we provide troubleshooting suggestions for difficult sample acquisitions on a mass cytometer. © 2020 Elsevier Inc. All rights reserved.

Differentiation of tomatoes based on isotopic, elemental and organic markers

Date: 2020
Authors: Floare-Avram, C;Covaciu, F;Voica, C;Puscas, R;Feher, I;Marincas, O;Magdas, D;
References: J Food Sci Technol 1 1
Keywords/Products: ELAN;ICP;Meinhard;
In this study, 41 tomato samples were investigated by means of stable isotope ratios (d13C, d18O and d2 H), elemental content, phenolic compounds and pesticides in order to classify them, according to growing conditions and geographical origin. Using investigated parameters, stepwise linear discriminant analysis was applied and the differences that occurred between tomato samples grown in greenhouses compared to those grown on field, and also between Romanian and abroad purchased samples were pointed out. It was shown that Ti, Ga, Te, d2 H and d13C content were able to differentiate Romanian tomato samples from foreign samples, whereas Al, Sc, Se, Dy, Pb, d18O, 4,40 -DDT could be used as markers for growing regime (open field vs. greenhouse). For the discrimination of different tomato varieties (six cherry samples and fourteen common sorts) grown in greenhouse, phenolic compounds of 20 samples were determined. In this regard, dihydroquercetin, caffeic acid, chlorogenic acid, rutin, rosmarinic acid, quercetin and naringin were the major phenolic compounds detected in our samples. The phenolic profile showed significant differences between cherry tomato and common tomato. The contents of the chlorogenic acid and rutin were significantly higher in the cherry samples (90.27-243.00 lg/g DW and 160.60-433.99 lg/g DW respectively) as compared to common tomatoes (21.30-88.72 lg/g DW and 24.84-110.99 lg/g DW respectively). The identification of dihydroquercetin is of particular interest, as it had not been reported previously in tomato fruit.

Occupational low-level exposure to hard metals: cobalt and tungsten biomonitoring as an effective tool to evaluate the effectiveness of industrial hygiene interventions for risk management

Date: 2020
Authors: Paganelli, M;Fostinelli, J;Renzetti, S;Sarnico, M;Tomasi, C;Lovreglio, P;Pilia, I;Lecca, LI;De Palma, G;
References: Biomarkers 25 179-185
Keywords/Products: Meinhard;
Purpose: The aim of the study was to assess the exposure of Cobalt (Co) and Tungsten (W) in a group of hard metal tool sharpeners through a combined approach of air and biological monitoring, and to evaluate the effectiveness of a control and improvement intervention carried out in collaboration with the medical officers of the local Health Protection Agency, by biomonitoring.

The Romanian Consumer Among Education, Information, Health Risk, Food Quality and Ethics

Date: 2020
Authors: Voica, C;Rosu, C;Iordache, A;Pistea, I;Miricioiu, M;
References: Rev. Chim. 71 436-442
Keywords/Products: ELAN;ICP;ICP-MS;Meinhard;Perkin Elmer;
The food quality and the safety must be a constant concern both for consumers and for authorities. The education for quality and the active involvement, coherent and sustained by the state, through the implementation of a quality strategy at national level should be the main `forces` that can contribute to the implementation and certification of quality management systems in the agri-food sector. The meat and milk products are important components in the human diet; therefore, their contamination with heavy metals plays a significant role in the public health. The concentrations of several human essential trace elements (Mn, Cu, Zn and Ba) and toxic elements (As, Cd, Pb) were analysed in 95 animal-based foods, including meat, milk products and honey, collected from Romanian market. The inductively coupled plasma mass spectrometry technique (ICP-MS) was used for the determinations. In order to evaluate the potential health risk of the consumers due to metals intake via food ingestion, three indices were calculated, namely: the potential average daily dose (ADDpot, mg/kg/day), the hazard quotient (HQ) and the hazard index (HI). In terms of food safety, the toxic element concentrations in the majority of the investigated samples were below the maximum permitted levels set by Romanian and European legislation.

Sediment quality of a Ramsar site assessed by chemical and ecotoxicological approaches

Date: 2020
Authors: Araujo, G;Cruz, A;Gusso-Choueri, P;Saint’Pierre, T;Hauser-Davis, R;Martins, C;Abessa, D;
References: Regional Studies in Marine Science 35 101145
Keywords/Products: Meinhard;
The sediment quality of the Protected Cananéia-Iguape-Peruíbe Area (APA-CIP), listed as one of the Wetlands of International Importance (Ramsar Site), was assessed through geochemical and ecotoxicological analyses, in order to determine if organic and inorganic contaminants retained in the sediments were bioavailable to benthic organisms and could trigger negative effects. Lethal (Tiburonella viscana) and sublethal (Lytechinus variegatus and Nitokra sp.) ecotoxicological endpoints were assessed, as well as sediment texture and organic and inorganic contaminants in sediments obtained at six stations distributed along the APA-CIP. Sites under the influence of the maximum turbidity zone and close to the main local urban center (Cananéia city) presented the worst environmental conditions, indicated by sediment toxicities and high contaminants levels. These conditions may be associated to fine-grained sediments. Metal (Pb, Co, Ni and Zn) concentrations exceeded the regional Sediment Quality Guidelines (SQGs) at stations PT and PM, while Pb also exceeded the Canadian Interim Marine Sediment Quality Guidelines (ISQGs). Total Aliphatic Hydrocarbons (AH) were close to threshold sediment contamination values at PT (maximum turbidity zone). These findings indicate that metals from former mining activities reach APA-CIP, in addition to contaminants from local sources (urban centers, docks, fishing wharfs). Contaminants accumulate in low energy regions, where fine particle and organic matter contents are high. Toxicities appeared to be associated to contaminants, suggesting that the multiple local anthropogenic sources can produce ecological risks, indicating the need for multiple efforts to control external and internal contamination sources in this protected estuarine area.