Human Health Effects Assays

Discussion of the exponential increase in environmental toxicological information and an approach for organizing and using the information was presented by Lu and Wassom.1 A user\u27s guide to the Registry of Toxic Effects of Chemical Substances (RTECS) was published by NIOSH2 that defines the record layouts and describes the types of data contained in the computer tape version of the 1984 Edition of the RTECS.3 A text summarizing information on approximately 800 toxic chemicals was edited by Sittig.4 Milestone publications concerning fundamentals of toxicology with environmental applications included the works of Gentile,5 Ashby,6 Mortel mans,7 Thacker,8 and Ruppert.9 Brusick and Auletta10 discussed the developmental status of bioassays in genetic toxicology reviewed by the U. S. Environmental Protection Agency (EPA) Gene-Tox Work Groups

Successfully Teaching Ethics For Effective Learning

This paper is concerned with identifying keys to successfully teach ethics. The keys are: addressing the relevance challenge; striving to achieve a balance between the active engagement of students with issues and a critical analysis of choices in to be made in real-life situations; attending to or managing the learning process to include learning styles and experiential learning; debriefing experientially-oriented learning activities; and institutionalizing outcomes of ethics education objectives. The paper discusses results of a study that attempted to answer the question “What is required to successfully deliver experientially-oriented ethics educatio

Review of In-Place Treatment Techniques for Contaminated Surface Soils - Volume 2: Background Information for In Situ Treatment

This second volume of a two volume manual on in-place treatment of hazardous waste contaminated soil supports the treatment methodology described in Volume 1 (EPA- ). The information presented on monitoring to determine treatment effectiveness, characterization and evaluation of the behavior and fate of hazardous constituents in soil/waste systems, and properties (including adsorption, degradation, and volatilization parameters) for various compounds is intended to help the manual user in making more complex decisions and in selecting analyses concerning site, soil, and waste interactions. This report was submitted in partial fulfillment of Contract No. 68-03-3113 by Utah State University under the sponsorship of the U.S. Environmental Protection Agency. The report covers the period December 1982 to December 1984 and work was completed as of January 1984

Beneficial Reuse and Sustainability: The Fate of Organic Compounds in the Land-Applied Waste

Land application systems, also referred to as beneficial reuse systems, are engineered systems that have defined and permitted application areas based on site and waste characteristics to determine the land area size requirement. These terrestrial systems have orders of magnitude greater microbial capability and residence time to achieve decomposition and assimilation compared with aquatic systems. In this paper we focus on current information and information needs related to terrestrial fate pathways in land treatment systems. Attention is given to conventional organic chemicals as well as new estrogenic and pharmaceutical chemicals of commerce. Specific terrestrial fate pathways addressed include: decomposition, bound residue formation, leaching, runoff, and crop uptake. Molecular decomposition and formation of bound residues provide the basis for the design and regulation of land treatment systems. These mechanisms allow for assimilation of wastes and nondegradation of the environment and accomplish the goal of sustainable land use. Bound residues that are biologically produced are relatively immobile, degrade at rates similar to natural soil materials, and should present a significantly reduced risk to the environment as opposed to parent contaminants. With regard to leaching and runoff pathways, no comprehensive summary or mathematical model of organic chemical migration from land treatment systems has been developed. For the crop uptake pathway, a critical need exists to develop information for nonagricultural chemicals and to address full-scale performance and monitoring at more land application sites. The limited technology choices for treatment of biosolids, liquids, and other wastes implies that acceptance of some risks and occurrence of some benefits will continue to characterize land application practices that contribute directly to the goal of beneficial reuse and sustainability

Treatment of Pentachlorophenol with Manganese Oxide Addition to Biotic and Abiotic Sediments

Laboratory microcosms containing subsamples of a complex environmental sediment were used to evaluate the addition of oxidized manganese as the primary electron acceptor in the presence of pentachlorophenol (PCP) as the primary electron donor. Manganese oxide (MnO2) particles were added to poisoned abiotic and non-poisoned biotic microcosms and incubated at 11°C in the presence of sediment samples that were shown capable of mineralizing PCP with indigenous microorganisms. Reduction in PCP concentration and production of reduced manganese was measured for both abiotic and biotic systems. PCP was observed to be transformed most rapidly and to the greatest extent in non-poisoned microcosms. Rate and extent of PCP transformation were increased when MnO2 was added. Rate and extent of PCP transformation were least, but still significant, in abiotic (poisoned) microcosms when MnO2 was added. Reduction in PCP sediment concentration was consistently correlated with an increase in production of reduced manganese (Mn+2). The addition of MnO2 was therefore shown to cause a decrease in PCP concentration in a naturally occurring complex environmental sediment. Reduced iron was observed suggesting that both manganese and iron were used as primary electron acceptors. Moreover, higher concentrations of Mn+2 were found in solution than +2Fe. This may support thermodynamic evidence that manganese is preferentially used over iron in some redox reactions. Addition of synthetic MnO2 particles via a permeable reaction wall or direct slurry injection, may represent a potential treatment approach for the abiotic as well as biotic reduction of PCP in sediment and ground water environments

An orally bioavailable broad-spectrum antiviral inhibits SARS-CoV-2 in human airway epithelial cell cultures and multiple coronaviruses in mice

Coronaviruses (CoVs) traffic frequently between species resulting in novel disease outbreaks, most recently exemplified by the newly emerged SARS-CoV-2, the causative agent of COVID-19. Herein, we show that the ribonucleoside analog β-D-N4-hydroxycytidine (NHC, EIDD-1931) has broad spectrum antiviral activity against SARS-CoV-2, MERS-CoV, SARS-CoV, and related zoonotic group 2b or 2c Bat-CoVs, as well as increased potency against a coronavirus bearing resistance mutations to the nucleoside analog inhibitor remdesivir. In mice infected with SARS-CoV or MERS-CoV, both prophylactic and therapeutic administration of EIDD-2801, an orally bioavailable NHC-prodrug (β-D-N4-hydroxycytidine-5′-isopropyl ester), improved pulmonary function, and reduced virus titer and body weight loss. Decreased MERS-CoV yields in vitro and in vivo were associated with increased transition mutation frequency in viral but not host cell RNA, supporting a mechanism of lethal mutagenesis in CoV. The potency of NHC/EIDD-2801 against multiple coronaviruses and oral bioavailability highlight its potential utility as an effective antiviral against SARS-CoV-2 and other future zoonotic coronaviruses

Insight into the evolution of the Solanaceae from the parental genomes of Petunia hybrida

Petunia hybrida is a popular bedding plant that has a long history as a genetic model system. We report the whole-genome sequencing and assembly of inbred derivatives of its two wild parents, P. axillaris N and P. inflata S6. The current assemblies include 91.3% and 90.2% coverage of their diploid genomes (1.4 Gb; 2n=14) containing 32,928 and 36,697 protein-coding genes, respectively. The Petunia lineage has experienced at least two rounds of paleohexaploidization, the older gamma hexaploidy event, which is shared with other Eudicots, and the more recent Solanaceae paleohexaploidy event that is shared with tomato and other Solanaceae species. Transcription factors that were targets of selection during the shift from bee- to moth pollination reside in particularly dynamic regions of the genome, which may have been key to the remarkable diversity of floral color patterns and pollination systems. The high quality genome sequences will enhance the value of Petunia as a model system for basic and applied research on a variety of unique biological phenomena

Visualization and Identification of IL-7 Producing Cells in Reporter Mice

Interleukin-7 (IL-7) is required for lymphocyte development and homeostasis although the actual sites of IL-7 production have never been clearly identified. We produced a bacterial artificial chromosome (BAC) transgenic mouse expressing ECFP in the Il7 locus. The construct lacked a signal peptide and ECFP (enhanced cyan fluorescent protein ) accumulated inside IL-7-producing stromal cells in thoracic thymus, cervical thymus and bone marrow. In thymus, an extensive reticular network of IL-7-containing processes extended from cortical and medullary epithelial cells, closely contacting thymocytes. Central memory CD8 T cells, which require IL-7 and home to bone marrow, physically associated with IL-7-producing cells as we demonstrate by intravital imaging

Visualization and Identification of IL-7 Producing Cells in Reporter Mice

Interleukin-7 (IL-7) is required for lymphocyte development and homeostasis although the actual sites of IL-7 production have never been clearly identified. We produced a bacterial artificial chromosome (BAC) transgenic mouse expressing ECFP in the Il7 locus. The construct lacked a signal peptide and ECFP (enhanced cyan fluorescent protein ) accumulated inside IL-7-producing stromal cells in thoracic thymus, cervical thymus and bone marrow. In thymus, an extensive reticular network of IL-7-containing processes extended from cortical and medullary epithelial cells, closely contacting thymocytes. Central memory CD8 T cells, which require IL-7 and home to bone marrow, physically associated with IL-7-producing cells as we demonstrate by intravital imaging