The UD researchers have devised tiny cargo-carrying systems many times smaller than a human hair. These systems, or carriers, are made from molecules called peptides that help provide structure for cells and tissues.

The research team is working to program these nanoparticle carriers to selectively bind to degrading collagen in the body. Collagen is a protein that helps plump up or provide structure to connective tissue — everything from our skin to our bones, tendons and ligaments.

When collagen degrades, as a result of disease or injury, the nanoparticles designed by the Kiick lab can attach and remain at the injury site longer than many current treatment options. This allows for the possibility of delivering site-specific medicines over longer periods of time — from days to weeks.

In one collaborative project that involves this work, Kiick is trying to develop drug carriers that could be useful in treating osteoarthritis. Osteoarthritis is a degenerative joint disorder characterized by inflammation, pain and stiffness. According to the Centers for Disease Control and Prevention, it affects 32.5 million Americans.

Early studies with Christopher Price, an associate professor in biomedical engineering, suggests that these nanoparticles can be retained in tissue and knee joints. In other related studies, Kiick and her students have shown that drugs can be encapsulated and retained in the nanoparticles, until released by changes in temperature.

“We are interested in learning how to release drugs that can help not just with pain management, but also with slowing down disease progression,” said Kiick, Blue and Gold Distinguished Professor of Materials Science and Engineering. “It has been key that we have been able to collaborate with the Price laboratory in this type of work.”

For a long time, small molecule corticosteroids have been a standard of care for managing pain in osteoarthritic joints. Because the joint is full of thick, sticky fluid and is under constant mechanical stress and motion, these small-molecule drugs get expelled from the fluid around the knee pretty quickly, in minutes.

“We are hopeful that by controlling the nanoparticle composition and structure,” said Kiick, “we will be able to finely control, or tune, the drug delivery behavior to provide longer-lasting relief for people with inflammatory conditions, such as osteoarthritis.”

The paper’s key findings demonstrate the research team’s ability to control the shape of the nanoparticles, which will impact how well they can bind to tissue in the body and stay in a particular location. The research team also can precisely control the size of the nanoparticles, which has implications for how they might be retained at the injection site and also how they may be used by particular cells before being removed from the body. Finally, the paper describes some of the very fine details of how the specific building blocks inside these peptide molecules can affect the temperature at which those different shaped and sized nanoparticles can be disassembled to release a medicine.

The research builds on Kiick’s previous patented and patent-pending work in this area, but she said it is collaboration with others that is driving forward promising results. While the Kiick lab brings expertise in creating novel materials that can be used as delivery systems; Arthi Jayaraman, Centennial Term Professor for Excellence in Research and Education in the Department of Chemical and Biomolecular Engineering, is helping the team understand factors related to temperature sensitivity of the delivery vehicles and to develop computational tools that can help the research team characterize the vehicle’s shape.

Meanwhile, Price’s expertise in understanding post-traumatic osteoarthritis has been key to developing methods to use these nanoparticles to potentially treat disease. Price is exploring how particular drugs and cells interact, which may inform what specific classes of medicines are useful in treating osteoarthritis that develops following traumatic injury. The collaboration will help the Kiick lab tailor what types of nanoparticle devices can be used to deliver these different classes of medicines.

According to Kiick, thinking big, the team could imagine loading a custom cocktail of medicines into the drug-delivering nanoparticles capable of delivering relief over varying timescales and temperatures. The researchers already have the right material nanostructure that can allow this to happen; now they are exploring how to trigger the nanoparticles to release specific medications under particular conditions.

“You could imagine injecting these encapsulated medications at the knee,” she explained. “Then, when you want one medication to be released, the patient could ice their knee. If another drug is needed to provide relief over a longer time-period, heat could be applied.”

It could be a really simple way to help people manage chronic conditions that cause a lot of pain and reduce mobility. And because the treatment is local, it could reduce side effects that can occur when drugs have to be taken at high doses or over prolonged periods of time.

“If these delivery vehicles could reduce painful effects of osteoarthritis, or delay when osteoarthritis symptoms emerge, there could be important implications for improving quality of life for many people,” Kiick said.

Stacey J.T. Hust, associate dean in the Murrow College of Communication, and Jessica Fitts Willoughby, associate professor of communication, conducted a survey of 13- to 17-year-olds in Washington State to find out how marijuana advertising and the location of marijuana retailers influence adolescents’ intentions to use the drug. The researchers also asked participants about their outcome beliefs — whether or not they thought using marijuana would be good for them personally and or socially.

Their research shows regular exposure to marijuana advertising on storefronts, billboards, retailer websites and other locations increased the likelihood of adolescents using marijuana.

“While there are restrictions against using advertising designed specifically to target youth, it does still appear to be having some influence,” Willoughby said. “Our research suggests a need to equip adolescents with the knowledge and skills to critically evaluate marijuana advertisements.”

Location of retail stores also played a role but the results of the survey were mixed.

While the actual density of marijuana retailers in an area was not associated with adolescents’ intentions to use, study participants who said they lived within five miles of a marijuana shop were more likely to report intentions to use the drug than those who perceived they lived farther away.

“This was especially the case when they also reported having positive beliefs about marijuana use,” Hust said. “The study participants who felt positively about marijuana and perceived living close to retailers were the most likely to report intentions to use marijuana.”

The results of the research team’s study could have significant policy implications as states that have legalized recreational marijuana use grapple with ways to adhere to the drug’s legal status while trying to prevent adolescent marijuana use.

For instance, most states with legalized marijuana restrict placing retailers and advertisements next to schools, but other locations, where adolescents live and spend a lot of their time, remain largely unregulated.

“Our findings are particularly relevant given that most states that have legalized recreational marijuana have not restricted their proximity to neighborhoods or living areas, which may be particularly challenging in large metropolitan areas,” Hust said. “States may want to consider using census data to identify the proportion of teens living in particular areas as they identify the location for marijuana retailers.”

The researchers are currently in the process of conducting a new experiment where they are testing different types of advertisements to see how young people interpret and respond to them.

“One of the things this research and other studies suggest is that these advertisements are pretty prolific in certain areas and we want to see what type of appeals are used in the advertisements and how those appeals affect viewers,” Hust said. “Our long-term goal is really to develop a better understanding of how adolescents can make heathy and informed decisions in an environment in which marijuana is legal.”

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Materials provided by Washington State University. Original written by Will Ferguson. Note: Content may be edited for style and length.

Researchers led by Jens Hoeijmakers, first author of the study and postdoctoral research fellow at the National Centre of Competence in Research PlanetS at the Universities of Bern and Geneva, examined data that had been collected by the high-resolution HARPS spectrograph. They were able to show that a total of at least seven gaseous metals occur in the atmosphere of WASP-121b. The results were recently published in the journal Astronomy & Astrophysics.

Unexpectedly much going on in the atmosphere of exoplanet WASP-121b

WASP-121b has been extensively studied since its discovery. “The earlier studies showed that there is a lot going on in its atmosphere,” explains Jens Hoeijmakers. And this despite the fact that astronomers had assumed that ultra-hot planets have rather simple atmospheres because not many complex chemical compounds can form in such blistering heat. So how did WASP-121b come to have this unexpected complexity?

“Previous studies tried to explain these complex observations with theories that did not seem plausible to me,” says Hoeijmakers. The studies had suspected that molecules containing the relatively rare metal vanadium were the main cause of the complex atmosphere in WASP-121b. According to Hoeijmakers, however, this would only make sense if a more common metal, titanium, were missing in the atmosphere. So Hoeijmakers and his colleagues set out to find another explanation. “But it turned out that they were right,” admits Hoeijmakers unequivocally. “To my surprise, we actually found strong signatures of vanadium in the observations.” At the same time, however, titanium was missing. This in turn confirmed Hoeijmakers’ assumption.

Vaporised metals

But the team made other, unexpected discoveries. In addition to vanadium, they newly discovered six other metals in the atmosphere of WASP-121b: Iron, chromium, calcium, sodium, magnesium and nickel. “All metals evaporated as a result of the high temperatures prevailing on WASP-121b,” explains Hoeijmakers, “thus ensuring that the air on the exoplanet consists of evaporated metals, among other things.”

A new era in exoplanet research

Such detailed results allow researchers to draw conclusions about the chemical processes that take place on such planets, for example. This is a crucial skill for the not too distant future, when larger, more sensitive telescopes and spectrographs will be developed. These will allow astronomers to study the properties of smaller, cooler rocky planets similar to Earth. “With the same techniques we use today, instead of just detecting signatures of gaseous iron or vanadium, we will be able to focus on biosignatures, signs of life such as the signatures of water, oxygen and methane,” says Hoeijmakers.

The extensive knowledge about the atmosphere of WASP- 121b not only confirms the ultra-hot character of the exoplanet, but also underlines the fact that this field of research is entering a new era, as Hoeijmakers puts it: “After years of cataloguing what is out there, we are now no longer just taking measurements,” explains the researcher, “but we are really beginning to understand what the data from the instruments show us. How planets resemble and differ from each other. In the same way, perhaps, that Charles Darwin began to develop the theory of evolution after characterizing countless species of animals, we are beginning to understand more about how these exoplanets were formed and how they work.”

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Materials provided by University of Bern. Note: Content may be edited for style and length.