Medical Bulletin 04/July/2023

Here are the top medical news for the day:

AI enables opportunistic screening for splenomegaly using volumetric thresholds.

According to an accepted manuscript published in AJR using an automated deep-learning AI tool, as well as weight-based volumetric thresholds, might afford large-scale evaluation for splenomegaly on CT examinations performed for any indication.

Noting that, historically, the standard linear splenic measurements used as a surrogate for splenic volume yielded suboptimal performance in detecting volume-based splenomegaly, “the weight-based volumetric thresholds indicated the presence of splenomegaly in most patients who underwent pre-liver transplant CT,” explained corresponding author Perry J. Pickhardt.

Reference: Automated Deep Learning Artificial Intelligence Tool for Spleen Segmentation on CT: Defining Volume-Based Thresholds for Splenomegaly, American Journal of Roentgenology, DOI 10.2214/AJR.23.29478

New bacterial blueprint to combat antibiotic resistance.

A team of scientists from around the globe, including those from Trinity College Dublin, has gained high-res structural insights into a key bacterial enzyme, which may help chemists design new drugs to inhibit it and thus suppress disease-causing bacteria. Their work is important as fears continue to grow around rising rates of antibiotic resistance.

The scientists, led by Martin Caffrey used next-gen X-ray crystallography and single particle cryo-electron microscopy techniques to “look under the bacterial bonnet” and produce a molecular blueprint of the full-length enzyme that may be used to design drugs that attack any structural weaknesses

Because the enzyme is not found in humans – it only exists in bacteria and helps them build stable cell membranes through which things are transported in and out of cells – it is of huge potential significance as a therapeutic target as any bespoke drug designed to attack it should have fewer side-effects for patients.

Reference: Science Advances, DOI 10.1126/sciadv.adf5799

Pathogenic bacteria exploit intestinal mucus sugar to infect the gut.

A new study by researchers at the University of British Columbia (UBC) and BC Children’s Hospital shows the sugar sialic acid, which makes up part of the protective intestinal mucus layer, fuels disease-causing bacteria in the gut.

The findings suggest a potential treatment target for intestinal bacterial infections and a range of chronic diseases linked to gut bacteria, including inflammatory bowel disease (IBD), celiac disease, irritable bowel syndrome, and short bowel syndrome.

For the study, the researchers examined Citrobacter rodentium, an intestinal bacterial pathogen of mice that are used to model infections with human E. coli. The team discovered that the bacteria have genes involved in sialic acid consumption, and when these genes are removed, the bacteria’s growth is impaired.

Reference: Sialic acid plays a pivotal role in licensing Citrobacter rodentium's transition from the intestinal lumen to a mucosal adherent niche, Proceedings of the National Academy of Sciences DOI 10.1073/pnas.2301115120