Dental researchers reveal bacterial conversations

Dental researchers are exploring how bacterial “conversations” in the mouthshape the ecology of dental plaque—and how interrupting those signals could favor a healthier microbial balance without harming beneficial species.

A team from the College of Biological Sciences and the School of Dentistry at the University of Minnesota has detailed how bacterial communication via N-acyl homoserine lactones (AHLs) influences the composition of oral biofilms, particularly the shift from health-associated bacteria toward species linked to periodontal disease.

In dental plaque, which contains hundreds of microbial species, AHL signals canbe produced in oxygen-rich zones above the gumline and perceived by bacteria in oxygen-poor niches below the gumline.

“Understanding how bacterial communities communicate and organize themselves may ultimately give us new tools to prevent periodontal disease,” says Mikael Elias, associate professor in the College of Biological Sciences and a senior author of the study.

The findings were published in the journal npj Biofilms and Microbiomes.

Removing PFAs from groundwater may get easier

The group of synthetic “forever chemicals” known as PFAS—per- and polyfluoroalkyl substances—have been mass produced for decades in consumer products like frying pans, water-resistant clothing, food packaging, and cosmetics. While previous research has demonstrated the potential to destroy selected PFAS in laboratory-based settings, a new study led by researchers from Brown University, the University of Minnesota, Jacobs Engineering, an environmental tech company called Arq Inc., and the U.S. Navy suggests a promising path to mitigating PFAS in real-world situations.

Researchers wanted to see whether a specially engineered, ultrafine carbon material called colloidal carbon product (CCP) could be injected underground to trap PFAS in groundwater. They tested this using a method called “push-pull” testing, which involves first pushing the carbon into the soil to create an underground filter and then pulling water back out to see if PFAS levels dropped after passing through the filter.

The paper found:

• PFAS concentrations dropped by up to four orders of magnitude in the field test, from more than 50,000 ng/L to below detection limits, 10 months after injection.
• The treatment effectively removed both long-chain and short-chain PFAS—an important advancement because short-chain PFAS are typically more difficult to capture.
• A cost analysis found that long-term operating costs of CCP treatment would be less than half those of other PFAS-removal methods, making it a cost-effective alternative for sites requiring decades of remediation.

“This study shows that we can create an effective treatment zone underground that dramatically reduces PFAS levels with far lower long-term costs,” says Matt Simcik, a professor in the School of Public Health and coauthor of the study.

The findings were published in The Journal of Hazardous Materials.

A new explanation for differing symptoms in sickle cell patients

A breakthrough study led by researchers at the University of Minnesota could explain why patients with the same genetic sickle cell mutation experience different levels of pain, organ damage, and response to treatment.

Sickle cell disease is an inherited lifelong disorder that affects millions of people worldwide. It causes red blood cells, which are normally flexible and doughnut-shaped, to become stiff and crescent-shaped in low-oxygen environments. This leads to blockages, excruciating pain and reduced life expectancy.

The study used advanced microfluidic “chips” that mimic human blood vessels to see how blood flow is disrupted by different types of stiff blood cells.

“Our work bridges the gap between how single cells behave and how the entire blood supply flows,” says David Wood, a professor in the College of Science and Engineering and a senior author of the study.

This study was published in Science Advances.

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