All that is silver is not toxic: silver ion and particle kinetics reveals the role of silver ion aging and dosimetry on the toxicity of silver nanoparticles.

Background: When suspended in cell culture medium, nano-objects composed of soluble metals such as silver can dissolve resulting in ion formation, altered particle properties (e.g. mass, morphology, etc.

Dysregulation of macrophage activation profiles by engineered nanoparticles.

Although the potential human health impacts from exposure to engineered nanoparticles (ENPs) are uncertain, past epidemiological studies have established correlations between exposure to ambient air pollution particulates and the incidence of pneumonia and lung infections. Using amorphous silica and superparamagnetic iron oxide (SPIO) as model high production volume ENPs, we examined how macrophage activation by bacterial lipopolysaccharide (LPS) or the lung pathogen Streptococcus pneumoniae is altered by ENP pretreatment. Neither silica nor SPIO treatment elicited direct cytotoxic or pro-inflammatory effects in bone marrow-derived macrophages.

Magnetic particle detection (MPD) for in-vitro dosimetry.

In-vitro tests intended for evaluating the potential health effects of magnetic nanoparticles generally require an accurate measure of cell dose to promote the consistent use and interpretation of biological response. Here, a simple low-cost inductive sensor is developed for quickly determining the total mass of magnetic nanoparticles that is bound to the plasma membrane and internalized by cultured cells. Sensor operation exploits an oscillating magnetic field (f0=250kHz) together with the nonlinear response of particle magnetization to generate a harmonic signal (f3=750kHz) that varies linearly with particulate mass (R(2)>0.

Comparison of field methyl isothiocyanate flux following Pacific Northwest surface-applied and ground-incorporated fumigation practices.

Background: A fumigant volatilization emission was conducted in Washington State in the fall of 2008 to estimate flux following applications of metam sodium by modified low-boom-height (LBH) center-pivot chemigation and soil-incorporated shank injection. This study was performed in a commercial potato field circle to assess emission rates and total cumulative field loss of methyl isothiocyanate (MITC) (the biologically active conversion product of metam sodium) under conditions typical for fall Pacific Northwest potato preplant fumigation. This assessment provides regionally specific MITC emission rate information for modeling appropriate field-edge set-back buffer distances for bystander protection.

Viral load and clinical disease enhancement associated with a lentivirus cytotoxic T lymphocyte vaccine regimen.

Effective DNA-based vaccines against lentiviruses will likely induce CTL against conserved viral proteins. Equine infectious anemia virus (EIAV) infects horses worldwide, and serves as a useful model for lentiviral immune control. Although attenuated live EIAV vaccines have induced protective immune responses, DNA-based vaccines have not.