Week in Review: May 23–27

Potential link between microbial infection and Alzheimer’s disease; CRISPR-enabled cell lineage tracing; image irregularities lead to anticipated retraction; brain glucose metabolism and consciousness; exploring emotional contagion; Zika-related microcephaly risk estimated

Tracy Vence
May 27, 2016

Alzheimer’s-infection link?

In mice, nematodes, and cultured human cells, scientists from Harvard University and Massachusetts General Hospital and their colleagues this week showed that amyloid-β peptides can trap invading microbes, suggesting a potential link between infection and Alzheimer’s—a disease characterized in part by an accumulation of amyloid-β plaques in the brain.

“Amyloid-β is overdue for an update,” said Douglas Ethell of Western University of Health Sciences in California who was not involved in the work. “For too long it’s been viewed as a useless byproduct that wreaks havoc on the human brain. This paper adds to a growing body of evidence that amyloid-β serves important physiological roles that we are only now beginning to understand.”

Lineage tracing

Using a new approach, called genome editing of synthetic target arrays for lineage tracing, Harvard scientists and their colleagues have followed the lives of mutation-tagged zebrafish cells.

“This method can be used to unravel any process that involves cell division,” said geneticist Aravinda Chakravarti of Johns Hopkins University School of Medicine who was not involved in the research. “It’s a highly significant piece of work.”

Awaited retraction

Three years after commenters first raised concerns with it, the authors and editors of a 2011 PLOS Biology study this week retracted the publication. The retraction follows on investigations by the authors’ institution, the State University of Campinas, and PLOS. The authors said that image irregularities several post-publication peer reviewers identified were “inadvertent” and did not affect the study’s conclusions.

A spokesperson for the State University of Campinas told The Scientist that the institution is working “to put together a special office to deal with research integrity.”

Quantifying consciousness

Brain glucose metabolism may provide a way for researchers to assess a brain-injured patient’s consciousness, according to a team led by investigators at the University of Copenhagen. “In nearly all cases, whole-brain energy turnover directly predicted either the current level of awareness or its subsequent recovery,” study coauthor Ron Kupers said in a statement. “In short, our findings indicate that there is a minimal energetic requirement for sustained consciousness to arise after brain injury.”

Catching feelings

Can people “catch” the emotions of others? Evidence in support of this idea is accumulating, and scientists are beginning to pinpoint potential mechanisms behind so-called emotional contagion.

Zika-microcephaly risk

A fetus whose mother is infected with Zika during the first trimester of her pregnancy has a risk of between 1 percent and 13 percent of developing microcephaly, researchers at the US Centers for Disease Control and Prevention and their colleagues have estimated.

“It might make sense that first trimester carries the greatest risk but [that] remains to be seen as we get more individual level data,” Christina Chambers of the University of California, San Diego, told STAT News.