Assessment of the Polychlorinated Biphenyl (PCB) Occurrence in Copper Sulfates and the Influential Role of PCB Levels on Grapes

<div><p>Copper sulfates (CuSO₄) are widely used as the primary component of fungicides in the grape industry. The agricultural-grade CuSO₄ that we collected from Chinese nationwide markets were found to be contaminated by polychlorinated dibenzo-<i>p</i>-dioxins and dibenzofurans and high levels of polychlorinated biphenyls (Σ₁₉PCBs: 0.32~9.51 ng/g). In the following research, we studied the impact of CuSO₄ application on PCB levels in grape products through a field experiment, and conducted a national survey to speculate the role that CuSO₄ played on the occurrence of PCB in grapes. In the field experiment, an obvious increase of PCBs in grape leaves (from 174 to 250 pg/g fw) was observed after Bordeaux mixture (the main component of which is CuSO₄) application. As to the main PCB congener in CuSO₄, the most toxic CB 126 (toxic equivalency factor = 0.1) also increased in grape peels (from 1.66 to 2.93 pg/g fw) after pesticide spray. Both the correlation study and the principal component analysis indicated that environmental factors were dominant PCB contributors to grapes, and grapes from e-waste dismantling area containing the highest PCBs also proved the notion. It is worth noting that this report describes the first research examining PCBs in CuSO₄ and its influence on agricultural products to date.</p></div

Descriptions of sampling project and corresponding sample IDs in the field experiment.

<p>Descriptions of sampling project and corresponding sample IDs in the field experiment.</p

The (a) loading plot and (b) score plot of the principle component analysis (PCA) of PCBs in field grape peels, grape pulps, grape leaves, air, soil and copper sulfate samples after BM application.

<p>C1 and C2 were the CuSO₄ used in the field experiment; A7 was the passive air sampler in experimental area during July 28th~November 5^th; P10-P12, U10-U12 and L7-L8 were the grape peels, pulps and leaves obtained after BM spray in experimental area respectively.</p

DataSheet1_Corrigendum: Prognostic Values and Clinical Significance of S100 Family Member’s Individualized mRNA Expression in Pancreatic Adenocarcinoma.DOC

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Concentrations of Σ₁₇PCDD/Fs and Σ₁₉PCBs in agricultural-grade (n = 10) and analytical-grade (n = 4) CuSO₄.

<p>The box upper and under lines represent the 25th and 75th percentiles, respectively, and the three horizontal bars represent the 5th, 50th, and 95th percentiles. * represent the 1% and 99%, □ represent mean values.</p

DataSheet2_Corrigendum: Prognostic Values and Clinical Significance of S100 Family Member’s Individualized mRNA Expression in Pancreatic Adenocarcinoma.ZIP

The full text of this article can be freely accessed on the publisher's website

DataSheet1_Prognostic Values and Clinical Significance of S100 Family Member’s Individualized mRNA Expression in Pancreatic Adenocarcinoma.doc

Objective: Pancreatic adenocarcinoma (PAAD) is a common malignant tumor worldwide. S100 family (S100s) is wildly involved in regulating the occurrence, development, invasion, metastasis, apoptosis, and drug resistance of many malignant tumors. However, the expression pattern, prognostic value, and oncological role of individual S100s members in PAAD need to be elucidated.Methods: The transcriptional expression levels of S100s were analyzed through the Oncomine and GEPIA, respectively. The protein levels of S100s members in PAAD were studied by Human Protein Atlas. The correlation between S100 mRNA expression and overall survival and tumor stage in PAAD patients was studied by GEPIA. The transcriptional expression correlation and gene mutation rate of S100s members in PAAD patients were explored by cBioPortal. The co-expression networks of S100s are identified using STRING and Gene MANIA to predict their potential functions. The correlation of S100s expression and tumor-infiltrating immune cells was tested by TIMER. Pathway activity and drug target analyzed by GSCALite.Results: 13 S100s members were upregulated in PAAD tissues. 15 S100s members were associated with TP53 mutation. Expression levels of S100A3/A5/A6/A10/A11/A14/A16/B/P/Z were significantly correlated with the pathological stage. Prognosis analysis demonstrated that PAAD patients with low mRNA levels of S100A1/B/Z or high levels of S100A2/A3/A5/A10/A11/A14/A16 had a poor prognosis. Immuno-infiltration analysis showed that the mRNA levels of S100A10/A11/A14/A16 were correlated with the infiltration degree of macrophages in PAAD. Drug sensitivity analysis showed that PAAD expressing high levels of S100A2/A6/A10/A11/A13/A14/A16 maybe resistant to small molecule drugs.Conclusion: This study identifies the clinical significance and biological functions of the S100s in PAAD, which may provide novel insights for the selection of prognostic biomarkers.</p

Depassivation of Aged Fe⁰ by Divalent Cations: Correlation between Contaminant Degradation and Surface Complexation Constants

The dechlorination of trichloroethylene (TCE) by aged Fe⁰ in the presence of a series of divalent cations was investigated with the result that while no significant degradation of TCE was observed in Milli-Q water or in solutions of Ba²⁺, Sr²⁺, or Ca²⁺, very effective TCE removal was observed in solutions containing Mg²⁺, Mn²⁺, Co²⁺, Fe²⁺, Ni²⁺, Zn²⁺, Cu²⁺, or Pb²⁺. The rate constants of TCE removal in the presence of particular cations were positively correlated to the log <i>K</i> representing the affinity of the cations for hydrous ferric oxide (HFO) surface sites though the treatments with Co²⁺ and Ni²⁺ were found to provide particularly strong enhancement in TCE degradation rate. The extent of Fe­(II) release to solution also increased with increase in log <i>K</i>, while the solution pH from both experimental measurement and thermodynamic calculation decreased with increasing log <i>K</i>. While the peak areas of Fe and O XPS spectra of the passivated ZVI in the presence of Ba²⁺, Sr²⁺, and Ca²⁺ were very close to those in Milli-Q water, very significant increases in surface Fe and O (and OH) were observed in solutions of Mg²⁺, Mn²⁺, Co²⁺, Fe²⁺, Ni²⁺, Zn²⁺, Cu²⁺ and Pb²⁺, revealing that the surface oxide layer dissolution is consistent with the recovery of aged Fe⁰ with respect to TCE degradation. The depassivation process is proposed to involve (i) surface complexation of cations on surface coatings of aged Fe⁰, (ii) dissolution of the hydrated surface as a consequence of magnetite exposure, and (iii) transport of electrons from underlying Fe⁰ via magnetite to TCE, resulting in TCE dechlorination and, for some cations (Co²⁺, Ni²⁺, Cu²⁺, and Pb²⁺), reduction to their zero or +1 valence state (with potential for these reduced metals to enhance TCE degradation)

Depassivation of Aged Fe⁰ by Inorganic Salts: Implications to Contaminant Degradation in Seawater

In this study, aged (iron oxide coated) Fe⁰ was applied to the degradation of trichloroethylene (TCE) in seawater. It was found that while the aged Fe⁰ was inactive with regard to TCE degradation in Milli-Q water, more than 95% of the TCE present was degraded in real and synthetic seawater solutions after exposure to aged Fe⁰ for 21 days. Results with individual salts from the synthetic seawater revealed that no significant TCE degradation was observed in the presence of Na₂SO₄, CaCl₂, and NaHCO₃. Partial TCE degradation (28.4%) was observed in 500 mM NaCl after 21 days, while a similar extent of degradation to that found in the seawater solutions was observed in 50 mM solutions of magnesium salts (MgCl₂ and MgSO₄). Results of open circuit potential analysis suggested that the Fe⁰ corrosion potential was not a key determinant of extent of TCE reduction since the corrosion potential decreased to levels similar to that of Fe⁰/Fe²⁺ in the presence of all salts examined. Lower final pH values and higher dissolved Fe­(II) concentrations were observed in the presence of magnesium salts compared to other salts. Formation of the surface complex >FeOMg⁺ was identified as being critical to protonation of surface sites, reductive dissolution of the passivating Fe­(III) oxyhydroxide layer coating the underlying Fe⁰ and enhancement in extent of TCE reduction. These findings provide insight into the molecular-scale mechanism of depassivation of aged Fe⁰ by inorganic salts with particular implications for the Fe⁰-mediated degradation of contaminants in saline natural waters such as seawater and saline groundwaters

Depassivation of Aged Fe⁰ by Ferrous Ions: Implications to Contaminant Degradation

Investigation of the effects of ferrous iron (Fe­(II)) on the ability of aged (iron oxide coated) Fe⁰ to degrade trichloroethylene (TCE) has revealed that, while neither aged Fe⁰ nor Fe­(II) separately were able to degrade TCE, approximately 95% of the TCE present was degraded after exposure to a mixture of aged Fe⁰ and Fe­(II) for 21 days. The rates of TCE degradation increased with an increase in Fe­(II) concentration from 0 to 1.6 mM and then reached a relative plateau. Results of Fe­(II) “adsorption” studies revealed that the equilibrium pH decreased significantly with an increase in Fe­(II) concentration. Proton release during adsorption of Fe­(II) to iron oxide coatings was identified as being responsible for promotion of surface dissolution and, concomitantly, enhancement in extent of TCE reduction by aged Fe⁰. Results of open circuit potential analysis and Tafel plot measurement showed that the corrosion potential of aged Fe⁰ (<i>E</i>_corr) in the presence of Fe­(II) decreased to levels similar to that of Fe⁰/Fe²⁺, while significant increase in corrosion current (<i>I</i>_corr) and decrease in polarization resistance (<i>R</i>_p) were found with an increase in Fe­(II) concentration. The fact that the effects of different Fe­(II) concentrations on the <i>E</i>_corr, <i>I</i>_corr, and <i>R</i>_p was decoupled from their effects on TCE degradation by aged Fe⁰ suggested that the enhancement of TCE degradation in the presence of Fe­(II) was attributable to the dissolution of the Fe­(III) oxyhydroxide layer coating the aged Fe⁰. While the presence of Fe­(II) may also lead to transformation of the Fe­(III) (oxy)­hydroxide coating to more crystalline phases, the rate of reduction of compounds such as TCE by Fe­(II) associated with the Fe­(III) (oxy)­hydroxide coating is substantially slower than that mediated by Fe⁰. These findings provide new insight into the molecular-scale interaction of aged Fe⁰ and ferrous iron with particular implications for sustaining the reactivity of Fe⁰-mediated degradation of contaminants in iron-bearing environments