A group of white blood cells known as B cells play a key role in the human immune response but need a protein-targeting signal called mannose 6-phosphate (M6P) in order to proliferate, differentiate, and present immune cell-activating antigens, according to a study in The Journal of Cell Biology.

Immune cells slice up antigens in organelles called lysosomes and attach the fragments to complexes that display them on the cell surface in order for these peptides to bind and activate other immune cells. To ensure that they can cut up the antigens, cells steer newly made enzymes to lysosomes by tagging them with M6P molecules.

A team of researchers has identified the genetic mutation responsible for glycogen storage disease type IIIa in Inuit in northern Quebec, Canada, in a study published in CMAJ (Canadian Medical Association Journal). The paper identifies a mutation in the gene encoding the glycogen debranching enzyme (AGL), which had previously been undetected in a decade of investigation by the same authors.

Wildfires send hot flames and smoke high into the air, including black carbon emissions associated with climate change and risk to human health. Unless the United States adapts sensible forest management policies, which means fewer instances of the Department of the Interior and environmental lobbyists conspiring to manipulate science reports, carbon emissions from wildfires in the contiguous U.S. could increase by 50 percent by 2050 and double by 2100.

Some media, such as the New York Daily News and NBC, have reported that the Asian H5N1 strain of highly pathogenic avian influenza has now entered the United States. This is incorrect and they were told it was not the same strain by the United States Geological Survey and then suggested it was anyway.

There was avian flu that was recently found, in a green-winged teal in Washington state, but it is a different strain and is not known to harm humans nor has it been found in domestic poultry. 

Product bundling is a common marketing strategy but retailers need to draw attention to the value of a package deal since consumers prefer products that are packaged individually.

"The advantages of bundling products may not be as straightforward as previously thought. Consumers may not always be aware of a bundle's added value over a single item and this could undermine the entire purpose of the bundling strategy. Without drawing attention to a product bundle's added value, a bundle may not be perceived as more attractive than the respective single product without the add-on," write authors Tobias Krüger, André Mata, and Max Ihmels (all University of Heidelberg).

Too much sitting has been shown to increase the risk of chronic diseases, particularly diabetes, heart disease, and some types of cancer. Current guidelines suggest adults do 150 minutes of moderate intensity activity a week, but more than a third (35.6%) of adults worldwide are sufficiently inactive.

Furthermore, the proportion of time spent being inactive rises with age: from 55% (7.7 hours) at 20-29 years, to 67% (9.6 hours) in those aged 70-79 years.

Two articles published in The BMJ this week argue that the 150 minute target is beyond the reach of some, especially older people, and say we should be promoting the benefits of small increases in daily physical activity rather than focusing on meeting current recommendations.