TOP MEDICAL NEWS 28/JULY/2022

In a new study, published in Nature, neuroscientists at the Sainsbury Wellcome Centre at UCL investigated the reciprocal interactions between two brain regions that represent visual working memory in mice. The team found that communication between these two loci of working memory, the parietal cortex, and premotor cortex, was co-dependent on instantaneous timescales.

SWC researchers compared a working memory-dependent task with a simpler working memory-independent task. In the working memory task, mice were given a sensory stimulus followed by a delay and then had to match the next stimulus to the one they saw prior to the delay. This meant that during the delay the mice needed a representation in their working memory of the first stimulus to succeed in the task and receive a reward. In contrast, in the working memory-independent task, the decision the mice made on the secondary stimulus was unrelated to the first stimulus.

Ref: Dr. Ivan Voitov et al, Nature: 'Cortical feedback loops bind distributed representations of working memory' DOI: 10.1038/s41586-022-05014-3

Preliminary evidence shows the potential for a fully-automated, online behavioral obesity treatment program to serve as a pragmatic resource in the primary care setting, according to a new study in Obesity, The Obesity Society's (TOS) flagship journal.

The current study is one of the first times that a fully-automated obesity treatment program has been tested pragmatically in a large, primary care network with clinicians responsible for identifying patients, providing the program, and supporting its use.

Ref: J. Graham Thomas et. al, Innovative, online automated obesity treatment program shows weight-loss results, Obesity

3." No pain, no gain" approach improves walking ability with peripheral artery disease

This study examined the effects of home-based walking for exercise among 264 people with PAD who were participating in a randomized clinical trial, called the Low-Intensity Exercise Intervention in PAD (LITE), which included 305 people overall. From September 2015 to December 2019, participants enrolled in the LITE study at four U.S. medical centers. Their average age was 69 years, 48% were women and 61% were Black adults.

Researchers randomly assigned participants to one of three groups for 12 months. The first group (38%) walked at home at a comfortable pace; the second group (41%) walked at home at a pace that induced leg symptoms; while the third group (21%) did not walk for exercise. Both walking exercise groups wore an ActiGraph, a device that monitored the intensity of their walking and the time walked.

Ref: Mary M. McDermott et. al, "No pain, no gain" approach improves walking ability with peripheral artery disease, AMERICAN HEART ASSOCIATION, Journal of the American Heart Association, DOI: 10.1161/JAHA.121.025063

4. People respond differently to psychedelic drugs genetics could be the reason

Recently, there's been renewed interest and research in using psychedelic compounds that stimulate serotonin receptors in the brain because of several promising results from clinical trials. These receptors bind serotonin (5-hydroxytryptamine; 5-HT) and other similar amine-containing molecules, helping regulate people's mood, perceptions, cognition, and emotions, as well as their appetite.

In particular, the serotonin receptor known as 5-HT2A is responsible for mediating the effects of psychedelic drugs. However, there are several naturally occurring, random genetic variations, known as single nucleotide polymorphisms, that can impact the 5-HT2A receptor's structure and function. So, Bryan Roth and colleagues wanted to explore how variations in the serotonin 5-HT2A receptor impact the in vitro activity of four psychedelic therapies.

Ref: 5-HT2A SNPs Alter the Pharmacological Signaling of Potentially Therapeutic Psychedelics, ACS Chemical Neuroscience, 27-Jul-2022, 10.1021/acschemneuro.1c00815