Abstract  Environmental Fate Monitoring Information

Abstract  Cell transformation models have been established for studying the cellular and molecular basis of the neoplastic process. Transformation models have also been utilized extensively for studying mechanisms of chemical carcinogenesis and, to a lesser degree, screening chemicals for their carcinogenic potential. Complexities associated with the conduct of cell transformation assays have been a significant factor in discouraging broad use of this approach despite their reported good predictivity for carcinogenicity. We previously reported that many of the experimental difficulties with the Syrian hamster embryo (SHE) cell transformation assay could be reduced or eliminated by culturing these cells at pH 6.7 culture conditions compared to the historically used pH 7.1-7.3. We and others have shown that morphological transformation (MT), the earliest recognizable phenotype in the multi-step transformation process and the endpoint used in the standard assay to indicate a chemica

Abstract  BIOSIS COPYRIGHT: BIOL ABS. The objective of this research was to identify chemical, physical, bacteriological, and viral contaminants, and their sources, which present the greatest health threat in public ground water supplies in the USA; and to classify (prioritize) such contaminants and relative to their health concerns. The developed contaminant prioritization methodology was based on frequency of occurrence and adverse health effects. Adverse health effects were based on carcinogenic potency, toxicity, hazardous chemical priorities and drinking water standards. Application of the methodology for wellhead protection areas, (WHPAs) revealed that approximately 200 different contaminants have been detected in the nation's public ground water supplies. The seven chemical constituents with the highest priority were arsenic, chromium, cadmium, carbon tetrachloride, chloroform, 1, 1-dichloroethylene, and ethylene dibromide. Other contaminants of concern were trichloroethylene, nitrates, barium, 1,1,

Abstract  Metal free 2,3,9,10,16,17,23,24-Octakis(Octyloxy)-29H,31H Phthalocyanine and its derivatives containing zinc and copper have been used to fabricate thin films through the Langmuir-Blodgett (LB) Thin Film Fabrication technique. These highly ordered homogeneous, nanoscale thin films' characterization has been investigated using UV-Visible Spectrophotometer. The gas sensing properties of these thin films has been investigated using both Surface Plasmon Resonance (SPR) and Quartz Crystal Microbalance (QCM) Techniques. Several groups of volatile organic compounds including benzene and toluene (aromatic hydrocarbon) methanol and ethanol (alcohol) and chloroform, dichloromethane and carbon tetrachloride (chlorinated aliphatic hydrocarbons) have been used as analyte molecules. The sensor response of the thin films through interaction with the gas molecules has been analyzed in terms of dipole/dipole interaction or hydrogen bonding. It is seen that the analyte gas molecules with high refractive index show a higher response in the SPR technique compared to QCM. Also, a central metal atom effect on gas sensing has not been observed by the SPR technique while the experiments performed using the QCM technique showed that the central metal atom enhances the gas response.

Abstract  Extracts from the European mistletoe or Viscum album L. have been known as secondary medicaments, widely used in treatment of a number of disorders. Also, they have been reported to exert certain pharmacological (e.g. cytotoxic and immunomodulatory) effects in vitro and in vivo. The in vivo effect of aqueous extracts of European mistletoe (Viscum album L.) grown on plums on biochemical parameters in rats, prior and after carbon-tetrachloride-induced hepatotoxicity was examined in this study. Three sets of experiments were conducted, applying three different concentrations of aqueous Viscum album, from plum extract. Administration of CCl4 impaired defence antioxidant mechanism, particularly by depletion of liver glutathione (GSH) content and reduction of activities of catalase (CAT) and peroxidase (Px). Induction of CCl4 also caused high increase of lipid peroxidation (LP) and decrease of glutathione reductase (GR) levels. Pretreatment with examined Viscum album extract inhibited CCl4-induced liver injury by decreasing LP and increasing GSH content. bringing the levels of antioxidant enzymes to control values. CCl4-induced increases in serum alanine transaminase (ALT), aspartate transaminase (AST) and bilirubin were dramatically supressed by the aqeous mistletoe grown on plums extract treatment. Hepatic DNA content haven't been changed much upon treatment with Viscum extract, but certain decrease in DNA content was observed in CCl4 treated group. What is also important, CCl4 caused a significant increase in hepatic hydroxyproline content, compared to the control group. However, the mistletoe extract treatment attenuated this increase, indicating that examined mistletoe extracts could exhibit certain hepato-protective effect. Values of investigated parameters showed significant dosage dependence, although positive results were obtained for all examined concentrations of Viscum album L. from plum extract.

Abstract  The capacity of an anaerobic granular sludge for serving as an immobilizing mechanism for quinone-respiring bacteria was evaluated. The inoculum was continuously fed with a basal medium containing the humic model compound, anthraquinone-2,6-disulfonate (AQDS), as a terminal electron acceptor. Complete reduction of AQDS was achieved by the granular sludge for a prolonged period in an anaerobic bioreactor provided with a mixture of volatile fatty acids as a substrate. Phylogenetic analysis revealed the enrichment and immobilization of AQDS-respiring bacteria appearing as dominant organisms in the microbial population of the AQDS-supplemented reactor, compared to a reactor control operated under methanogenic conditions. The consistent quinone-reducing capacity observed in the consortium indicates that it is feasible to apply quinone-reducing microorganisms in continuous bioreactors and this ability can potentially be important in wastewaters rich in humic substances. The quinone reducing activity could also be applied to accelerate the conversion of xenobiotics susceptible to reductive biotransformations such as azo dyes and polychlorinated compounds in continuous bioreactors.

Abstract  Soil humic substances can be used as redox mediators in accelerating the biotransformation of organic pollutants, and humus-respiring bacteria are widely distributed in soils. However, the impact of humic substances on the soil microbial community during the biotransformation of organic pollutants is expected to be crucial while remains to be unclear. In this study, the biostimulation of indigenous microbial communities and the consequent effects on anaerobic transformation of pentachlorophenol (PCP) by a model humic substance, anthraquinone-2,6-disulfonate (AQDS), were systematically investigated in a paddy soil. The addition of AQDS was observed to increase the production of HCl-extractable Fe(II) and enhance the PCP transformation rates consequently. The pseudo-first-order rate constants of the PCP transformation showed a positive exponential relationship with the AQDS dosage. The terminal restriction fragment length polymorphism (T-RFLP) results indicated the substantial effect of added AQDS on soil microbial community. The enhanced abundance of Geobacter sp. was disclosed to be most critical for accelerated PCP transformation when with AQDS, in which Geobacter sp. functioned for promoting the generation of active Fe(II) and consequently enhancing the PCP transformation rates. The transformation rates of PCP were exponentially correlated with the abundance of Geobacter sp. positively. The findings are expected to improve the understanding of diversity and ubiquity of microorganisms in humic substances-rich soils for accelerating the transformations of soil chlorinated pollutants.

Abstract  Intradiffusion coefficients of acetylacetone (AcAc) and DMF/DMSO/benzene in binary systems over the entire concentration range at 303.15 K were determined by H-1 diffusion-order spectroscopy (DOSY) nuclear magnetic resonance (NMR) method based pulse field gradient (PFG). The densities and viscosities of the above three binary systems at 303.15 K were also studied and employed to calculate the excess molar volumes (V-E) and deviations in viscosity (Delta eta). Besides, experiments were carried out at 333.15 K for the system of AcAc + DMF. The solvent and temperature effect upon the difference in D between enol and keto tautomers, the tautomeric equilibrium and excess properties (V-E and Delta eta) were discussed as well. Isotherms of V-E as a function of mole fraction of AcAc (x(1)) show positive deviations in benzene but negative deviations in DMF and DMSO, whereas isotherms of Delta eta as a function of x(1) record positive deviations in DMF but negative in benzene and DMSO. V-E values show more negative and Delta eta values are less positive in the system of AcAc + DMF at 333.15 K compared to 303.15 K. The V-E and Delta eta were fitted to a Redlich-Kister type equation and the measured results were interpreted concerning molecular interactions in the solutions. (C) 2015 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.