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Breast cancer can harbor intracellular bacteria, which may have an impact on metastasis and therapeutic responses. Silver nanoparticles are FDA-approved for their antimicrobial potential, plus they have pleiotropic benefits for eradicating cancer cells. In the current work we synthesized photothermal silver nanoparticles (AgNPs) with an absorption at 800 nm for heat generation when exposed to near-infrared laser irradiation. Breast cell lines MCF 10A, MCF7, and MDA MB 231 were infected with Pseudomonas aeruginosa, and their response to AgNPs, heat, or photothermal therapy (PTT) was evaluated. The results demonstrate that the application of a brief heating of cells treated with AgNPs offers a synergistic benefit in killing both infected and non-infected cells. Using 10 µg/mL of AgNPs plus laser stimulation induced a temperature change of 12 °C, which was sufficient for reducing non-infected breast cells by 81–94%. Infected breast cells were resistant to PTT, with only a reduction of 45–68%. In the absence of laser stimulation, 10 µg/mL of AgNPs reduced breast cell populations by 10–65% with 24 h of exposure. This concentration had no impact on the survival of planktonic bacteria with or without laser stimulation, although infected breast cells had a 42–90% reduction in intracellular bacteria. Overall, this work highlights the advantages of AgNPs for the generation of heat, and to augment the benefits of heat, in breast cancer cells harboring intracellular infection. [ABSTRACT FROM AUTHOR]

Information on the economic benefits of natural resource improvement is an important, yet often overlooked, consideration in environmental decision-making. In 2010, the Environmental Protection Agency established the Chesapeake Bay Total Maximum Daily Load (TMDL) that set regulatory limits for nitrogen, phosphorus, and sediment needed to restore the Chesapeake Bay. Meanwhile, the Bay jurisdictions developed implementation plans to achieve these limits. Environmental benefits of achieving the TMDL would accrue due to on-the-ground changes in land use and land management that improve the health, and therefore productivity, of land and water in the watershed. These changes occur both due to the outcomes of achieving the TMDL (i.e., cleaner water) and as a result of the measures taken to achieve those outcomes. This study quantified these changes, then translated them into dollar values for various ecosystem services, including water supply, food production, recreation, and aesthetics. We estimate the total economic benefit of implementing the TMDL at $22.5 billion per year (in 2013 dollars), as measured as the improvement over current conditions, or at $28.2 billion per year (in 2013 dollars), as measured as the difference between the TMDL and a business-as-usual scenario. These considerable benefits should be considered alongside the costs of restoring the Chesapeake Bay. [ABSTRACT FROM PUBLISHER]

Early applications of wilderness economic research demonstrated that the values of natural amenities and commodities produced from natural areas could be measured in commensurate terms. To the surprise of many, the economic values of wilderness protection often exceeded the potential commercial values that might result from resource extraction. Here, the concepts and tools used in the economic analysis of wilderness are described, and the wilderness economic literature is reviewed with a focus on understanding trends in use, value, and economic impacts. Although our review suggests that each of these factors is trending upward, variations in research methods plus large gaps in the literature limit understanding of long-run trends. However, as new data on wilderness use, visitor origins, and spatially referenced features of landscapes are becoming increasingly available, more robust economic analysis of both onsite and offsite wilderness economic values and impacts is now becoming possible. [ABSTRACT FROM AUTHOR]