You are hereNews

News


Variability in bioreactivity linked to changes in size and zeta potential of diesel exhaust particles in human immune cells.

Paul J. Lioy, Ph.D. - Sun, 08/31/2014 - 02:00

Related Articles

Variability in bioreactivity linked to changes in size and zeta potential of diesel exhaust particles in human immune cells.

PLoS One. 2014;9(5):e97304

Authors: Sarkar S, Zhang L, Subramaniam P, Lee KB, Garfunkel E, Strickland PA, Mainelis G, Lioy PJ, Tetley TD, Chung KF, Zhang J, Ryan M, Porter A, Schwander S

Abstract
Acting as fuel combustion catalysts to increase fuel economy, cerium dioxide (ceria, CeO2) nanoparticles have been used in Europe as diesel fuel additives (Envirox™). We attempted to examine the effects of particles emitted from a diesel engine burning either diesel (diesel exhaust particles, DEP) or diesel doped with various concentrations of CeO2 (DEP-Env) on innate immune responses in THP-1 and primary human peripheral blood mononuclear cells (PBMC). Batches of DEP and DEP-Env were obtained on three separate occasions using identical collection and extraction protocols with the aim of determining the reproducibility of particles generated at different times. However, we observed significant differences in size and surface charge (zeta potential) of the DEP and DEP-Env across the three batches. We also observed that exposure of THP-1 cells and PBMC to identical concentrations of DEP and DEP-Env from the three batches resulted in statistically significant differences in bioreactivity as determined by IL-1β, TNF-α, IL-6, IFN-γ, and IL-12p40 mRNA (by qRT-PCR) and protein expression (by ELISPOT assays). Importantly, bioreactivity was noted in very tight ranges of DEP size (60 to 120 nm) and zeta potential (-37 to -41 mV). Thus, these physical properties of DEP and DEP-Env were found to be the primary determinants of the bioreactivity measured in this study. Our findings also point to the potential risk of over- or under- estimation of expected bioreactivity effects (and by inference of public health risks) from bulk DEP use without taking into account potential batch-to-batch variations in physical (and possibly chemical) properties.

PMID: 24825358 [PubMed - in process]

Categories: Publications from UCDPER Members

Therapeutic Potential of a Non-Steroidal Bifunctional Anti-Inflammatory and Anti-Cholinergic Agent against Skin Injury Induced by Sulfur Mustard.

Jeffrey D. Laskin, Ph.D. - Sun, 08/31/2014 - 02:00

Related Articles

Therapeutic Potential of a Non-Steroidal Bifunctional Anti-Inflammatory and Anti-Cholinergic Agent against Skin Injury Induced by Sulfur Mustard.

Toxicol Appl Pharmacol. 2014 Aug 12;

Authors: Chang YC, Wang JD, Hahn RA, Gordon MK, Joseph LB, Heck DE, Heindel ND, Young SC, Sinko PJ, Casillas RP, Laskin JD, Laskin DL, Gerecke DR

Abstract
Sulfur mustard (bis(2-chloroethyl) sulfide, SM) is a highly reactive bifunctional alkylating agent inducing edema, inflammation, and the formation of fluid-filled blisters in the skin. Medical countermeasures against SM-induced cutaneous injury have yet to be established. In the present studies, we tested a novel, bifunctional anti-inflammatory prodrug (NDH 4338) designed to target cyclooxygenase 2 (COX2), an enzyme that generates inflammatory eicosanoids, and acetylcholinesterase, an enzyme mediating activation of cholinergic inflammatory pathways in a model of SM-induced skin injury. Adult SKH-1 hairless male mice were exposed to SM using a dorsal skin vapor cup model. NDH 4338 was applied topically to the skin 24, 48, and 72hr post-SM exposure. After 96hr, SM was found to induce skin injury characterized by edema, epidermal hyperplasia, loss of the differentiation marker, keratin 10 (K10), upregulation of the skin wound marker keratin 6 (K6), disruption of the basement membrane anchoring protein laminin 322, and increased expression of epidermal COX2. NDH 4338 post-treatment reduced SM-induced dermal edema and enhanced skin re-epithelialization. This was associated with a reduction in COX2 expression, increased K10 expression in the suprabasal epidermis, and reduced expression of K6. NDH 4338 also restored basement membrane integrity, as evidenced by continuous expression of laminin 332 at the dermal-epidermal junction. Taken together, these data indicate that a bifunctional anti-inflammatory prodrug stimulates repair of SM induced skin injury and may be useful as a medical countermeasure.

PMID: 25127551 [PubMed - as supplied by publisher]

Categories: Publications from UCDPER Members

The World Health Organization (WHO) Recommends Vaccine Composition for the 2011-2012 Northern Hemisphere Influenza Season

PandemicFlu.gov - Sun, 08/31/2014 - 02:00

The World Health Organization (WHO) Recommends Vaccine Composition for the 2011-2012 Northern Hemisphere Influenza Season

Categories: Government Agency News

Report: Imminent Terrorist Attack Warning By Feds on US Border

Homeland Security News - Fri, 08/29/2014 - 14:39

Islamic terrorist groups are operating in the Mexican border city of Ciudad Juarez and planning to attack the United States with car bombs or other vehicle born improvised explosive devices (VBIED). High-level federal law enforcement, intelligence and other sources have confirmed to Judicial Watch that a warning bulletin for an imminent terrorist attack on the [...]

This story comes to us via Homeland Security - National Terror Alert. National Terror Alert is America's trusted source for homeland security news and information.

Report: Imminent Terrorist Attack Warning By Feds on US Border

Categories: Homeland Security News

California Oregon Fire

FEMA Disaster Declarations - Mon, 08/25/2014 - 03:08

Fire Management Assistance Declaration number 5076 issued Mon, 08/25/2014 - 03:09

Categories: Government Agency News