Daily Briefing: Drugs like Ozempic seem to help everything from Alzheimer’s to infertility. But how?

Hello Nature readers, would you like to get this Briefing in your inbox free every day? Sign up here.

The difficulty of counting deaths in Gaza

Since Israel began military operations in the Gaza Strip in response to the attacks of 7 October 2023 carried out by Hamas, the official number of Palestinians killed has exceeded 41,000. The count comes from the local ministry of health and the number has been challenged as both an over- and under-estimate. It’s important to track fatalities to hold warring parties accountable and to advocate for the protection of civilians, says epidemiologist Zeina Jamaluddine. But with much of the population displaced and some entire families being wiped out with no one left to report the loss, some deaths are not being counted, says Emily Tripp, director of the non-profit watchdog Airwars. Only when the conflict ends or eases can researchers begin the work of getting more robust estimates of overall mortality through surveys, modelling and statistical tools, they say.

Nature | 7 min read

Sleuths flag 130 papers by one author

A team of scientist–sleuths has flagged data-integrity concerns in 130 studies authored by the same researcher, a specialist in women’s health and gynaecology, and his colleagues. Published between 2014 and 2023, the problems with the studies included oddities in reported statistics, unfeasible results and text that is identical to other papers. Some of the studies that were identified as potentially problematic have been included in analyses that could inform clinical practice, with potentially harmful consequences.

Nature | 9 min read

Reference: Journal of Gynecology Obstetrics and Human Reproduction paper

Youth depression differs in the brain

Regions of the brain in young people with severe depression are disrupted in different ways to adults with the condition. A mega-analysis of brain scans showed that connectivity was stronger in some parts of the brain in people aged 12-25 with major depressive disorder than in people without it, and weaker in others. Connectivity in the area of the brain associated with internalized thoughts was particularly strong. “While there is some overlap with the connectivity disruptions that we see in adults, there are also unique and specific circuit disruptions that we only see in youth with depression,” says neuroscientist Andrew Zalesky.

The Guardian | 4 min read

Reference: Nature Mental Health paper

Giant ‘evidence banks’ for policies that work

Funders are investing US$70 million into a plan to solve the problem of supplying evidence to governments. Their goal is to build a system that allows policymakers worldwide to quickly synthesize scientific evidence to help them develop policies on issues like climate change. Evidence syntheses are “everything the world knows about how to solve an important problem in one place”, says Will Moy, lead of the Campbell Collaboration. They’re routinely used in health, but not in other areas of policymaking. It can take years to extract meaning from a massive body of research.

Nature | 6 min read

Brain–computer interfaces

The state of brain-implant clinical trials

Implanted brain–computer interfaces (BCIs) have demonstrated tantalizing successes in restoring speech, movement or touch perception to paralyzed people in clinical trials. But, despite trials running since 1998, not one BCI has been approved by regulatory agencies for the medical device market. And there is no central repository for information on BCI research. To address this gap, three BCI researchers have conducted a review of trials up to 2023, including this very useful graphical timeline. They also suggest ways in which the sector needs to improve — such as by dealing with the considerable underrepresentation of women as trial participants.

Nature Reviews Bioengineering | 52 min read

Read more: A collection of articles in Nature Reviews Bioengineering address the promise and challenges of neurotechnologies — including brain interfaces and non-invasive brain stimulation.

Features & opinion

Obesity drugs treat so much — but how?

Evidence is growing that drugs such as Ozempic and Wegovy, which mimic the effects of the hormone GLP-1, have broad therapeutic benefits. They seem to reduce the risk of cardiovascular problems, slow the development of Parkinson’s disease and even suppress addiction in the same way they suppress appetite. But in a lot of cases, we still need to figure out one crucial piece of information: why they work. “If you are trying to capitalize on a possible therapeutic effect and make the next generation of a drug even better, then you ought to know where it is working and how it is working,” says endocrinologist Daniel Drucker.

Nature | 13 min read

We need more botanists and zoologists

The decline in the teaching of species-classification skills could derail efforts to support conservation, argues ecologist Dasheng Liu. “A lack of taxonomic knowledge, especially at the local level, is leading to errors,” he writes. “For example, in 2022, a common fish in Xiaoqing River, China, was mistakenly reported to be an endangered species, causing confusion among conservationists and the public.” He calls for the Kunming Biodiversity Fund — aimed at supporting global biodiversity conservation in low- and middle-income countries — to include a substantial pot of money for biodiversity education.

Nature | 5 min read