Nanotoxicology: a perspective and discussion of whether or not in vitro testing is a valid alternative

Despite the many proposed advantages related to nanotechnology, there are increasing concerns as to the potential adverse human health and environmental effects that the production of, and subsequent exposure to nanoparticles (NPs) might pose. In regard to human health, these concerns are founded upon the plethora of knowledge gained from research relating to the effects observed following exposure to environmental air pollution. It is known that increased exposure to environmental air pollution can cause reduced respiratory health, as well as exacerbate pre-existing conditions such as cardiovascular disease and chronic obstructive pulmonary disease. Such disease states have also been associated with exposure to the NP component contained within environmental air pollution, raising concerns as to the effects of NP exposure. It is not only exposure to accidentally produced NPs however, which should be approached with caution. Over the past decades, NPs have been specifically engineered for a wide range of consumer, industrial and technological applications. Due to the inevitable exposure of NPs to humans, owing to their use in such applications, it is therefore imperative that an understanding of how NPs interact with the human body is gained. In vivo research poses a beneficial model for gaining immediate and direct knowledge of human exposure to such xenobiotics. This research outlook however, has numerous limitations. Increased research using in vitro models has therefore been performed, as these models provide an inexpensive and high-throughput alternative to in vivo research strategies. Despite such advantages, there are also various restrictions in regard to in vitro research. Therefore, the aim of this review, in addition to providing a short perspective upon the field of nanotoxicology, is to discuss (1) the advantages and disadvantages of in vitro research and (2) how in vitro research may provide essential information pertaining to the human health risks posed by NP exposure.

What's in a title? An assessment of whether randomized controlled trial in a title means that it is one

In this study, we aimed to investigate whether studies published in orthodontic journals and titled as randomized clinical trials are truly randomized clinical trials. A second objective was to explore the association of journal type and other publication characteristics on correct classification.

I feel good whether my friends win or my foes lose: brain mechanisms underlying feeling similarity.

People say they enjoy both seeing a preferred social group succeed and seeing an adversary social group fail. At the same time, they state they dislike seeing a preferred social group fail and seeing an adversary social group succeed. The current magnetic resonance imaging study investigated whether-and if so, how-such similarities in reported feeling states are reflected in neural activities. American football fans anticipated success and failure situations for their favorite or their adversary teams. The data support the idea that feeling similarities and divergences expressed in verbal reports carry with them significant neural similarities and differences, respectively. Desired (favorite team likely to win and adversary team likely to lose) rather than undesired (favorite team likely to lose and adversary team likely to win) outcomes were associated with heightened activity in the supramarginal gyrus, posterior cingulate cortex, insula, and cerebellum. Precuneus activity additionally distinguished anticipated desirable outcomes for favorite versus adversary teams.