Analysis of cytotoxic effects of silver nanoclusters on human peripheral blood mononuclear cells ‘in vitro’

The antimicrobial properties of silver nanoparticles (AgNPs) have made these particles one of the most used nanomaterials in consumer products. Therefore, an understanding of the interactions (unwanted toxicity) between nanoparticles and human cells is of significant interest. The aim of this study was to assess the in vitro cytotoxicity effects of silver nanoclusters (AgNC, < 2 nm diameter) on peripheral blood mononuclear cells (PBMC). Using flow cytometry and comet assay methods, we demonstrate that exposure of PBMC to AgNC induced intracellular reactive oxygen species (ROS) generation, DNA damage and apoptosis at 3, 6 and 12 h, with a dose‐dependent response (0.1, 1, 3, 5 and 30 µg ml^–1). Advanced electron microscopy imaging of complete and ultrathin‐sections of PBMC confirmed the cytotoxic effects and cell damage caused by AgNC. The present study showed that AgNC produced without coating agents induced significant cytotoxic effects on PBMC owing to their high aspect ratio and active surface area, even at much lower concentrations (<1 µg ml^–1) than those applied in previous studies, resembling what would occur under real exposure conditions to nanosilver‐functionalized consumer products. Copyright © 2015 John Wiley & Sons, Ltd.     

Tuberculosis DALY-Gap: Spatial and Quantitative Comparison of Disease Burden Across Urban Slum and Non-slum Census Tracts

To quantitatively assess disease burden due to tuberculosis between populations residing in and outside of urban informal settlements in Rio de Janeiro, Brazil, we compared disability-adjusted life years (DALYs), or “DALY-gap.” Using the 2010 Brazilian census definition of informal settlements as aglomerados subnormais (AGSN), we allocated tuberculosis (TB) DALYs to AGSN vs non-AGSN census tracts based on geocoded addresses of TB cases reported to the Brazilian Information System for Notifiable Diseases in 2005 and 2010. DALYs were calculated based on the 2010 Global Burden of Disease methodology. DALY-gap was calculated as the difference between age-adjusted DALYs/100,000 population between AGSN and non-AGSN. Total TB DALY in Rio in 2010 was 16,731 (266 DALYs/100,000). DALYs were higher in AGSN census tracts (306 vs 236 DALYs/100,000), yielding a DALY-gap of 70 DALYs/100,000. Attributable DALY fraction for living in an AGSN was 25.4 %. DALY-gap was highest for males 40–59 years of age (501 DALYs/100,000) and in census tracts with <60 % electricity (12,327 DALYs/100,000). DALY-gap comparison revealed spatial and quantitative differences in TB burden between slum vs non-slum census tracts that were not apparent using traditional measures of incidence and mortality. This metric could be applied to compare TB burden or burden for other diseases in mega-cities with large informal settlements for more targeted resource allocation and evaluation of intervention programs.     

What is the evidence base for public involvement in health‐care policy?: results of a systematic scoping review

Background

Public involvement in health‐care policy has been advocated as a means to enhance health system responsiveness, yet evidence for its impact has been difficult to ascertain.

Objectives

To review the peer‐reviewed empirical evidence on outcomes of public involvement in health‐care policy.

Methods

We systematically searched PsychINFO and PubMed from November 2000 to April 2010 for empirical studies that reported on original research only; studies in languages other than English, German or French were excluded. Data were extracted using a standardized evidence table with a priori determined headings.

Main results

Nineteen studies were identified as eligible for inclusion in our review. We found that sound empirical evidence of the outcomes of public involvement activities in health care remains underdeveloped. The concept and the indicators used to examine and determine outcomes remain poorly specified and inconsistent, as does the reporting of the evidence. There was some evidence for the developmental role of public involvement, such as enhancing awareness, understanding and competencies among lay participants. Evidence for instrumental benefits of public involvement initiatives was less well documented.

Conclusions

Despite the growing body of work on public involvement in health‐care policy, evidence of its impact remains scarce; thus, firm conclusions about involvement activities that are appropriate and effective for policy development are difficult to draw. However, focus on outcomes risks missing the normative argument that involving the public in the health‐care policy process may be seen to be of intrinsic value.