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In situ chemical oxidation (ISCO) is considered a reliable technology to treat groundwater contaminated with high concentrations of organic contaminants. An ISCO oxidant, persulfate anion (S2O82−) can be activated by ferrous ion (Fe2+) to generate sulfate radicals (Eo = 2.6 V), which are capable of destroying trichloroethylene (TCE). The property of polarity inhibits S2O82− or sulfate radical (SO4−) from effectively oxidizing separate phase TCE, a dense non-aqueous phase liquid (DNAPL). Thus the oxidation primarily takes place in the aqueous phase where TCE is dissolved. A bench column study was conducted to demonstrate a conceptual remediation method by flushing either S2O82− or Fe2+ through a soil column, where the TCE DNAPL was present, and passing the dissolved mixture through either a Fe2+ or S2O82− fluid sparging curtain. Also, the effect of a solubility enhancing chemical, hydroxypropyl-β-cyclodextrin (HPCD), was tested to evaluate its ability to increase the aqueous TCE concentration. Both flushing arrangements may result in similar TCE degradation efficiencies of 35% to 42% estimated by the ratio of TCE degraded/(TCE degraded + TCE remained in effluent) and degradation byproduct chloride generation rates of 4.9 to 7.6 mg Cl− per soil column pore volume. The addition of HPCD did greatly increase the aqueous TCE concentration. However, the TCE degradation efficiency decreased because the TCE degradation was a lower percentage of the relatively greater amount of dissolved TCE by HPCD. This conceptual treatment may serve as a reference for potential on-site application. [Copyright &y& Elsevier]

Background: p63 is a member of the p53 family that has been implicated in maintenance of epithelial stem cell compartments. Previous studies demonstrated that p63 is downregulated in muscle-invasive bladder cancers, but the relationship between p63 expression and survival is not clear. Methodology/Principal Findings: We used real-time PCR to characterize p63 expression and several genes implicated in epithelial-to-mesenchymal transition (EMT) in human bladder cancer cell lines (n = 15) and primary tumors (n = 101). We correlated tumor marker expression with stage, disease-specific (DSS), and overall survival (OS). Expression of E-cadherin and p63 correlated directly with one another and inversely with expression of the mesenchymal markers Zeb-1, Zeb-2, and vimentin. Non-muscle-invasive (Ta and T1) bladder cancers uniformly expressed high levels of E-cadherin and p63 and low levels of the mesenchymal markers. Interestingly, a subset of muscle-invasive (T2-T4) tumors maintained high levels of Ecadherin and p63 expression. As expected, there was a strongly significant correlation between EMT marker expression and muscle invasion (p<0.0001). However, OS was shorter in patients with muscle-invasive tumors that retained p63 (p = 0.007). Conclusions/Significance: Our data confirm that molecular markers of EMT are elevated in muscle-invasive bladder cancers, but interestingly, retention of the ''epithelial'' marker p63 in muscle-invasive tumors is associated with a worse outcome. [ABSTRACT FROM AUTHOR]