New radar technique lets scientists probe invisible ice sheet region on Earth and icy worlds

Peer-Reviewed Publication

UNIVERSITY OF TEXAS AT AUSTIN

 

IMAGE: A HELICOPTER EQUIPPED WITH AN ICE-PENETRATING RADAR REFUELS ON THE ICE AT THE ARCTIC’S DEVON ISLAND. RESEARCHERS AT THE UNIVERSITY OF TEXAS INSTITUTE FOR GEOPHYSICS HAVE DEVELOPED A RESOLUTION-BOOSTING TECHNIQUE FOR THE INSTRUMENT. view more 

CREDIT: UNIVERSITY OF TEXAS INSTITUTE FOR GEOPHYSICS/COREY SKENDER

Scientists at the University of Texas Institute for Geophysics (UTIG) have developed a radar technique that lets them image hidden features within the upper few feet of ice sheets. The researchers behind the technique said that it can be used to investigate melting glaciers on Earth as well as detect potentially habitable environments on Jupiter’s moon Europa.

The near-surface layers of ice sheets are difficult to study with airborne or satellite ice-penetrating radar because much of what’s scientifically important happens too close to the surface to be accurately imaged. That has left scientists relying on ground instruments that give only limited coverage, or extracting ice cores — a difficult and time-consuming operation currently impossible to do on other planets.

The new radar technique combines two different radar bandwidths and looks for discrepancies as a way of boosting the resolution. Because the instruments are carried on airplanes or satellites, scientists can quickly survey vast regions of ice.

To test the new technique, the team flew radar surveys over the Devon Ice Cap in the Canadian Arctic where they mapped a slab-like layer of impermeable ice near the surface. Further analysis suggested that the ice layer is redirecting surface melt from the ice cap’s snow-packed surface into water channels downhill. The research was published May, 2023, in the journal The Cryosphere.

According to Kristian Chan, a graduate student at the UT Jackson School of Geosciences who devised the technique, the study’s findings about the ice slab layer could help scientists predict the future of the ice cap and its contribution to sea level rise.
 
“If you have only relatively thin ice layers then the firn [snow-packed surface layers] has the ability to absorb and retain surface meltwater,” Chan said. “But if these impermeable slabs are widespread then the contribution of surface melt to sea level rise is enhanced.”

Surface melt is normal on ice sheets during summer months. As the top of the previous winter’s snow warms up, meltwater sinks in and refreezes deeper in the snow, forming thin ice layers.

Most of the ice layers on Devon Ice Cap, however, are much thicker than expected, some forming slabs as much as 16 feet thick over several miles. That makes them very effective at redirecting meltwater, which the researchers confirmed when they matched the location of the thickest ice slabs with that of meltwater rivers.

Chan said the findings demonstrate what scientists can accomplish with the new technique.

“We used an airborne radar to find ice slabs on Devon Ice Cap, but the same thing applies for detecting layers with an orbiting radar at ice-covered ‘ocean’ worlds like Jupiter’s moon Europa,” he said.

Chan is part of a UTIG group, led by Senior Research Scientist Don Blankenship, that is developing a radar instrument called REASON, which will launch aboard NASA’s Europa Clipper in 2024. Along with a European Space Agency spacecraft that launched this year, scientists will soon have two ice-penetrating radar instruments investigating Jupiter’s moons Europa and Ganymede. Both radar systems are compatible with Chan’s technique. 

With the new technique, scientists will be able to peer into the upper few feet of the icy shells where they might find frozen brine, cryovolcanic remnants or even plume fallout deposits. All are either potential habitats or clues about habitable environments in the subsurface, said coauthor Cyril Grima, a UTIG research associate who is also part of the REASON team. 

“Kristian has given us the ability to see things in this hidden part just beneath the surface that is potentially accessible to future landers,” Grima said. “It’s really improved the reconnaissance ability of those radars.”

The research was supported by the NASA Texas Space Grant Consortium at UTIG, and the G. Unger Vetlesen Foundation. UTIG is a research unit of the UT Jackson School of Geosciences.

Devon Island is located in the Canadian Arctic. Its ice cap lies within the marked study area.

CREDIT

University of Texas Institute for Geophysics

The Devon Ice Cap in the Canadian Arctic. The map shows the extent of an ice layer buried among the ice cap’s snow packed surface. Analysis by researchers at the University of Texas Institute for Geophysics revealed that the thickest portions of the ice layer can channel meltwater into surface rivers (blue streaks), reducing the ice cap’s ability to hold water.

CREDIT

University of Texas Institute for Geophysics/Kristian Chan

Kristian Chan, a graduate student at The University of Texas at Austin Jackson School of Geosciences, operating an ice-penetrating radar during an aerial survey of an Antarctic ice sheet. Chan developed a technique that boosts the radar’s normally low resolution, allowing it to image hidden features in the ice sheet’s upper layers.

CREDIT

University of Texas Institute for Geophysics/Jamin Greenbaum

NASA Europa Clipper with REASON 

An illustration of NASA’s Europa Clipper spacecraft approaching Jupiter’s moon Europa. The spacecraft, which is planned to launch in 2024, will carry an ice-penetrating radar instrument developed by scientists at the University of Texas Institute for Geophysics.

CREDIT

NASA/JPL-Caltech

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JOURNAL

The Cryosphere

DOI

10.5194/tc-17-1839-2023 

METHOD OF RESEARCH

Imaging analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Spatial characterization of near-surface structure and meltwater runoff conditions across the Devon Ice Cap from dual-frequency radar reflectivity

How the immune system can alter our behavior

Peer-Reviewed Publication

YALE UNIVERSITY

New Haven, Conn. — Simply the smell of seafood can make those with an allergy to it violently ill — and therefore more likely to avoid it. The same avoidance behavior is exhibited by people who develop food poisoning after eating a certain meal.

Scientists have long known that the immune system played a key role in our reactions to allergens and pathogens in the environment, but it was unclear whether it played any role in prompting these types of behaviors towards allergic triggers.

According to Yale-led research published July 12 in the journal Nature, it turns out that the immune system plays a crucial role in changing our behaviors.

“We find immune recognition controls behavior, specifically defensive behaviors against toxins that are communicated first through antibodies and then to our brains,” said Ruslan Medzhitov, Sterling Professor of Immunobiology at Yale School of Medicine, investigator for the Howard Hughes Medical Institute, and senior author of the study.

Without immune system communication, the brain does not warn the body about potential dangers in the environment and does not try to avoid those threats, the study shows.

A team in the Medzhitov lab, led by Esther Florsheim, at the time a postdoctoral researcher at Yale and now an assistant professor at Arizona State University, and Nathaniel Bachtel, a graduate student at the School of Medicine, studied mice that had been sensitized to have allergic reactions to ova, a protein found in chicken eggs. As expected, these mice tended to avoid water laced with ova, while control mice tended to prefer ova-laced water sources. The aversion to ova-laced water sources in sensitized mice lasted for months, they found.

The team then examined whether they could alter the behavior of sensitized mice by manipulating immune system variables. They found, for instance, that mice allergic to ova lost their aversion to the protein in their water if Immunoglobulin E (IgE) antibodies, produced by the immune system, were blocked. IgE antibodies trigger the release of mast cells, a type of white blood cell that, along with other immune system proteins, plays a crucial role in communicating to areas of the brain that control aversion behavior. Without IgE as an initiator, the transmission of information was interrupted, so that mice no longer avoided the allergen.

Medzhitov said that the findings illustrate how the immune system evolved to help animals avoid dangerous ecological niches. Understanding how the immune system memorizes potential dangers, he added, could one day help suppress excessive reactions to many allergens and other pathogens.

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JOURNAL

Nature

Eliminating public health scourge can also benefit agriculture

Peer-Reviewed Publication

UNIVERSITY OF NOTRE DAME

 

IMAGE: RESEARCHERS FROM THE UNIVERSITY OF NOTRE DAME, IN A STUDY RECENTLY PUBLISHED IN NATURE, FOUND THAT REMOVING INVASIVE VEGETATION AT WATER ACCESS POINTS IN AND AROUND SEVERAL SENEGALESE VILLAGES REDUCED RATES OF SCHISTOSOMIASIS BY ALMOST A THIRD. view more 

CREDIT: UNIVERSITY OF NOTRE DAME

Schistosomiasis, a parasitic disease that causes organ damage and death, affected more than 250 million people worldwide in 2021, according to the World Health Organization.

One of the world’s most burdensome neglected tropical diseases, schistosomiasis occurs when worms are transmitted from freshwater snails to humans. The snails thrive in water with plants and algae that proliferate in areas of agricultural runoff containing fertilizer. People become infected during routine activities in infested water.

Researchers from the University of Notre Dame, in a study recently published in Nature, found that removing invasive vegetation at water access points in and around several Senegalese villages reduced rates of schistosomiasis by almost a third. As a bonus, the removed vegetation can also be used for compost and livestock feed.

“Disease, food, energy, water, sustainability and poverty challenges intersect in many ways, but are typically addressed independently,” said lead author Jason Rohr, the Ludmilla F., Stephen J. and Robert T. Galla College Professor and Department Chair in the Department of Biological Sciences at the University of Notre Dame. “We sought to break down these silos and identify win-win solutions, while demonstrating their cost effectiveness so that residents would hopefully adopt them widely.”

Rohr and his team spent seven years on the project, with research conducted in 23 villages and clinical trials in 16. They found that villages with substantial fertilizer use had more submerged vegetation. These villages had more snails and a higher prevalence of schistosomiasis infection in children, said Rohr, who is affiliated with the Notre Dame Environmental Change Initiative and the Eck Institute for Global Health.

Researchers hypothesized that removing vegetation could reduce infections while providing greater access to the open water that is crucial for daily activities and recreation. So, they conducted a three-year randomized controlled trial in 16 communities, where children were treated for their infections and the researchers removed more than 400 metric tons of vegetation in water access points from half the villages. These removals resulted in a decline in snail abundance as well as schistosomiasis infection rates being nearly a third lower than those observed in control villages.

Rohr’s team also tried to profitably improve food production by partly closing the nutrient loop, returning nutrients captured in the removed plants back to agriculture. So, they worked with local farmers to compost the vegetation for use on pepper and onion plants, increasing their yields, and demonstrated that the vegetation could be effectively used as cattle, sheep and donkey feed. Alexandra “Lexi” Sack, who worked as a postdoctoral researcher in Rohr’s lab from 2021 to 2023, assisted Senegal’s in-country team with the care and design of the sheep-feeding trials, and performed much of the analysis of the vegetation removal results.

“This is important work because it encompasses many different disciplines by combining schistosomiasis prevention and food security,” Sack said. “Often these interventions are separate when the neglected tropical diseases, which includes schistosomiasis, are contributing both to and resulting from poverty.”

With the expertise of co-authors Christopher B. Barrett, an economist at Cornell University, and Molly Doruska, a doctoral student also at Cornell, the research team demonstrated that the benefits of removing the vegetation and using it in agriculture were nearly nine times higher than the costs.

“We took this public nuisance, which is reducing health, and converted it into a private good that improves income,” Rohr said.

The team was also able to illustrate how to scale the project using artificial intelligence and satellite imagery to identify snail habitat and thus hotspots for schistosomiasis, which will allow them to target their intervention training to areas that need it the most.

Villagers helped with removing vegetation once they understood the public health benefits of the intervention, but in the long run, relying on voluntary labor may not be as effective as the researchers removing the vegetation.

“In the next steps, sociologists and economists on the project will quantify how the innovation affects quality of life and whether it is biased based on wealth, gender and/or age,” Rohr said.

The team will also investigate how biodigesters might be implemented to turn the aquatic vegetation into fertilizer and gas that can be used for cooking or to fuel generators for electricity production. Rohr said they hope to leverage investments by the Swiss government, which has committed to installing 60,000 biodigesters in Senegal for carbon credits.

The ongoing research could not be accomplished without all of the partners who contributed, especially the Senegalese citizens, Rohr said.

Christopher Haggerty, a postdoctoral student at Notre Dame during the study, contributed to this research. A complete list of co-authors can be found on the paper at Nature.

The research was funded by the National Institutes of Health, the National Science Foundation, the Indiana Clinical and Translational Sciences Institute and a Stanford seed grant.

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JOURNAL

Nature

DOI

10.1038/s41586-023-06313-z 

ARTICLE TITLE

A planetary health innovation for disease, food and water challenges in Africa

ARTICLE PUBLICATION DATE

12-Jul-2023

Rosé renaissance: Spanish study uncorks ultrasound for superior wine quality

Peer-Reviewed Publication

SOCIETY OF CHEMICAL INDUSTRY

Since the International Organisation of Vine and Wine (OIV) approved the use of ultrasound to promote the extraction of grape compounds back in 2019, its application for obtaining superior red wines has been studied extensively.

Now researchers are turning their attention to rosé – an expanding market which has seen strong growth over the past 15 years. A team from the University of Castilla-La Mancha and the University of Murcia in Spain used high-power ultrasound technology to treat Monastrell crushed grapes – a process known as sonication – and compared the resulting rosé to wine obtained after a four-hour maceration period.

In a recent paper published in the Journal of the Science of Food and Agriculture a research team describes the improvements to the colour and sensory profile of the sonicated wine, compared to the macerated sample.

Prof. Encarna Gomez Plaza from the University of Murcia, Spain, and corresponding author of the study explained the importance of the research for the wine industry. Speaking to SCI, she said: 

‘The application of ultrasound was primarily designed for reducing maceration time in red winemaking. However, experiences with white wines showed that the aroma fraction could be increased by sonicating crushed grapes. Therefore, we decided to study the effect of ultrasound in rosé wines, something which has not been done before.’

Traditionally, the maceration process has played a crucial role in the production of rosé wines, allowing for the extraction of essential aromatic compounds and colour-enhancing components. The process, in which the crushed grape skins are left in the juice, can last anywhere from a couple of hours to two days, prior to the grapes being pressed and fermented.

However, whilst it increases the rosé colour, extended maceration can cause oxidation of certain compounds in the wine, resulting in a bitter taste and other undesirable effects. This is where ultrasound comes in. Sonication by ultrasound causes the breakdown of grape skin cells, allowing desirable compounds to be extracted within a significantly shorter maceration time, thereby reducing the negative effects of oxidation.

Sensory analysis of the wines carried out by a trained panel with years of experience in wine sensory evaluations revealed the ultrasound-treated rosé wine to have a superior aroma.

‘Sonication gave rise to wines with intense red berry and flowery odours, with scores higher than those of wine from macerated grapes’, noted the authors.

Analysis of the chemical composition supported this – ultrasound treatment enhanced the extraction of several volatile compounds that improve aroma, such as terpenes, which can emit a floral or citrusy fragrance.

The team hopes that this study draws attention to the potential of ultrasound technology for producing high-quality rosé wines. They are now looking to other applications of high-power ultrasound in the wine industry.

‘We want to increase our knowledge on the effect of ultrasound in wineries. We are researching how to solve problems that sometimes appear during winemaking and the chemistry behind this behaviour’ noted Prof. Gomez Plaza.

 

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JOURNAL

Journal of the Science of Food and Agriculture

DOI

10.1002/jsfa.12757 

METHOD OF RESEARCH

Experimental study

ARTICLE TITLE

The technology of high-power ultrasound and its effect on the color and aroma of rosé wines

Psychedelic-assisted therapies for patients with PTSD

The resurgence of research into psychedelic-based treatments is poised to benefit many people who face mental health challenges, such as post-traumatic stress disorder, but how do they feel about it?

Peer-Reviewed Publication

MEDICAL UNIVERSITY OF SOUTH CAROLINA

 

IMAGE: MEDICAL UNIVERSITY OF SOUTH CAROLINA PSYCHIATRIST DR. JENNIFER JONES (LEFT) AND MELISSA MICHEL (RIGHT, RECLINING), LEAD THERAPIST FOR MUSC'S CENTERSPACE CLINIC, DEMONSTRATING PSYCHEDELIC-ASSISTED THERAPY. view more 

CREDIT: MEDICAL UNIVERSITY OF SOUTH CAROLINA. PHOTOGRAPH COURTESY OF DR. JENNIFER JONES.

Psychedelic-based therapies are poised to change the treatments that psychiatrists can offer patients.

“I often talk about psychedelic treatments as catalysts for change, for both the individual and the field of psychiatry,” said Medical University of South Carolina psychiatrist Jennifer Jones, M.D., who conducts research on these treatments.

The highly anticipated approval of MDMA, or “ecstasy,” to treat post-traumatic stress disorder would be the first for a psychedelic drug, ushering in changes for patients, mental health providers and society. The Food and Drug Administration is expected to issue a decision on MDMA-assisted therapy for PTSD in early 2024.

How well this revolutionary research will be implemented into practice will depend on patients’ willingness to undergo psychedelic-based treatments and their ability to access those treatments, said Jones. Jones’ latest research, published in Frontiers in Psychiatry, examines these potential barriers in a population that stands to benefit greatly from psychedelic therapies for PTSD: individuals that use substances.

Changing treatments and outcomes

Approval of psychedelic therapies could help patients with mental illnesses, particularly those with multiple or treatment-resistant disorders. PTSD is an often severe mental disorder that can occur after being exposed to a traumatic event. Current treatments, while improving symptoms in some patients, leave many without any benefit at all.

For the many people who have PTSD and habitually use alcohol or other substances, rates of nonresponse to treatment are even higher. Jones thinks this is unacceptable, so she started researching new approaches to treat patients with both PTSD and a substance use disorder.

A promising ‘new’ treatment option for patients with both PTSD and SUD may come from an ‘old’ group of drugs called psychedelics. Psychedelics include both natural (psilocybin, mescaline, DMT) and synthetic (LSD, MDMA) drugs. Natural psychedelics have been used medicinally and spiritually in traditional cultures for centuries. However, they were described scientifically mostly in the 1950s and 1960s.

“It is really interesting – in these early studies looking at psychedelic therapy for one indication, like PTSD, they noticed improvements in symptoms of another mental health disorder, like depression or SUD,” said Jones.

Since 2009, approximately 80 clinical trials involving MDMA have been completed or are ongoing, according to Clinicaltrials.gov. These trials investigate the use of MDMA in a wide range of disorders, including anxiety, depression, obsessive compulsive disorder, SUD and PTSD. These diverse studies highlight the potential effects of MDMA across multiple disorders, something that prior treatments have lacked.

“This is really important,” said Jones. “It is very common to have concurrent mental health disorders, so having a treatment like MDMA that could, for example, improve both PTSD and SUD symptoms is really exciting for the field.”

Currently, drugs used to treat PTSD may be given with or without another form of therapy, broadly referred to as “talk therapy.” For MDMA-assisted therapy, the talk therapy component is a fundamental part of the treatment.

“In the context of MDMA-assisted therapy for PTSD, MDMA is thought to dampen the fear response around the traumatic memory, allowing the participant to engage with the therapy team to process this memory, sometimes for the first time in their lives,” said Jones. “Instead of running from it, they can process the traumatic memory and move past it.”

This processing may also apply to other mental functions, perhaps accounting for MDMA’s ability to improve symptoms for other disorders, like SUD.

“Participants in psychedelic clinical trials have lasting benefits that come from changes in their behaviors, their thought processes and their interactions with others,” said Jones. “Participants often point to these changes as what made the difference in their symptoms.”

The immediate effects of MDMA during therapy are not without concern, however. Jones is often asked whether the MDMA will produce feelings of “ecstasy.” “Ecstasy is a common descriptor for the effects caused by recreational MDMA, used so frequently that it became a nickname for the drug. However, because this therapy is a difficult process of self-healing, MDMA in this context does not usually produce ecstasy, Jones said. This common concern points to some of the possible barriers that Jones wanted to assess in her recent publication.

Changing minds

For some, reluctance to receive MDMA-assisted therapy is tied to negative views of psychedelics and their recreational uses. In the 1970s, all psychedelics were classified as Schedule I substances, drugs with high-abuse potential without clinical benefits, tarnishing political and public perceptions of these drugs. Their recreational use and representations in media have continued to perpetuate this stigma.

Negative views of psychedelics and increasing regulatory control halted early promising research on psychedelics in Western medicine in the 1970s, reported the Multidisciplinary Association for Psychedelic Studies. It wasn’t until the 1990s that officially sanctioned psychedelic research resumed on a small scale, only accelerating in the 2010s. New government policies allowed psychedelic clinical research to resume, but public perceptions of psychedelics will determine the success of these drugs as treatments.

In Jones’ study, approximately 70% of survey respondents indicated their support for MDMA-based research and belief that MDMA could be useful for treating mental health disorders. A smaller group, 59%, would be willing to receive an MDMA-based treatment if it were recommended by a mental health provider. The survey results suggest that most people who use substances are open to MDMA research and would be willing to try an MDMA-based therapy.

Jones also examined the role of race and ethnicity on opinions about MDMA-assisted therapy. Despite their underrepresentation in psychedelic clinical trials, racial and ethnic groups had similar levels of support for MDMA research. However, there were small, but potentially important, differences in willingness to try an MDMA-based therapy. “While largely a hypothesis,” said Jones, “differences in willingness to participate in clinical trials are probably related to prior use or cultural beliefs.”

While this research brings up additional questions for Jones and colleagues, she believes these results can help researchers and mental health providers to understand how to develop and implement treatments more equitably for different patient and ethnic populations.

By discussing these issues prior to the FDA decision, Jones hopes steps can be taken to address patient concerns.

“It is my heartfelt goal that everyone who might benefit from MDMA-assisted therapy is able to receive treatment once it is available, and that they will not be held back by worries or stigma about the treatment,” said Jones. “For that to be a reality, we have to seek input directly from those most likely to benefit from the treatments that we are developing.”

 

# # #

About MUSC

Founded in 1824 in Charleston, MUSC is the state’s only comprehensive academic health system, with a unique mission to preserve and optimize human life in South Carolina through education, research and patient care. Each year, MUSC educates more than 3,200 students in six colleges – Dental Medicine, Graduate Studies, Health Professions, Medicine, Nursing and Pharmacy – and trains more than 900 residents and fellows in its health system. MUSC brought in more than $298 million in research funds in fiscal year 2022, leading the state overall in research funding. MUSC also leads the state in federal and National Institutes of Health funding, with more than $220 million. For information on academic programs, visit musc.edu.

As the health care system of the Medical University of South Carolina, MUSC Health is dedicated to delivering the highest-quality and safest patient care while educating and training generations of outstanding health care providers and leaders to serve the people of South Carolina and beyond. Patient care is provided at 16 hospitals (includes owned and equity stake), with approximately 2,700 beds and four additional hospital locations in development; more than 350 telehealth sites and connectivity to patients’ homes; and nearly 750 care locations situated in all regions of South Carolina. In 2022, for the eighth consecutive year, U.S. News & World Report named MUSC Health University Medical Center in Charleston the No. 1 hospital in South Carolina. To learn more about clinical patient services, visit muschealth.org.

MUSC has a total enterprise annual operating budget of $5.1 billion. The nearly 26,000 MUSC family members include world-class faculty, physicians, specialty providers, scientists, students, affiliates and care team members who deliver groundbreaking education, research, and patient

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JOURNAL

Frontiers in Psychiatry

DOI

10.3389/fpsyt.2023.1096298 

METHOD OF RESEARCH

Survey

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Perspectives on the therapeutic potential of MDMA: A nation-wide exploratory survey among substance users.

Bacterium associated with disease found in NC chiggers

Peer-Reviewed Publication

NORTH CAROLINA STATE UNIVERSITY

 

IMAGE: SCANNING ELECTRON MICROSCOPY IMAGE OF A CHIGGER. view more 

CREDIT: LOGANATHAN PONNUSAMY, NC STATE UNIVERSITY

A bacterium that causes a disease called scrub typhus – a disease not previously reported in the United States – has been detected in North Carolina, according to a new study by researchers at North Carolina State University and UNC-Greensboro. 

The researchers stress that scrub typhus, which can cause fever, headache and body aches – and can be fatal if left untreated by antibiotics – has not yet been detected in animals or people in the state.

The NC State researchers detected the bacterium – the genus is Orientia in the family Rickettsiaceae – at a high frequency while testing free living, larval (ready to bite) trombiculid mites, commonly called chiggers, in several different recreational parks in North Carolina.

“We wanted to see if chiggers in the United States carried Orientia,” said Loganathan Ponnusamy, an NC State principal research scholar in entomology and co-corresponding author of a paper that describes the research. “We haven’t in the past had the diagnostic tools to test for this specific bacterium at the genus level.”

“We set a black tile on the ground in 10 different North Carolina state parks and picked up chiggers as they crossed the tile. Microbiome studies allowed us to characterize all the bacteria in the chiggers. One park showed a 90% positivity rate for the bacterium (nine out of 10 chiggers captured); another showed an 80% positivity rate (eight of 10 chiggers captured). Other parks showed positivity rates of just 10%.”

Trombiculid mites are only parasitic in their larval stage. They search for vertebrate hosts – including humans – to bite, Ponnusamy says. 

“Chiggers can spread bacteria to people or rodents when they bite but can also pass bacteria to future generations of mites through their eggs,” he added.

The researchers say that scrub typhus presents symptoms similar to those of Rocky Mountain spotted fever, a disease generally ascribed to tick bites.

Scrub typhus is found more commonly in Asia and the Pacific, but in recent years has been detected in Africa and the Middle East. It is uncertain whether spread is caused by people or goods carrying chiggers from one place to another.

“We don’t know if this is a recent introduction into the state or if the bacterium has been here for years,” said R. Michael Roe, William Neal Reynolds Distinguished Professor of Entomology at NC State and co-author of the paper. “We also don’t know if the infected chiggers found in North Carolina actually will cause disease; this has to be determined in future work.”

“We also don't have information about whether the chigger infection rate is decreasing or increasing,” said Kaiying Chen, a postdoctoral research scholar at NC State and lead author of the paper.

The NC State and UNC-Greensboro researchers are resampling chiggers in the recreational park sites to see if the reported findings remain consistent.

The paper appears in the journal Emerging Infectious Diseases. Other co-authors include Nicholas V. Travanty and Charles S. Apperson from North Carolina State University; Reuben Garshong and Gideon Wasserberg from the University of North Carolina Greensboro; and Dac Crossley from the Georgia Museum of Natural History. 

Funding was provided by a grant from the National Institutes of Health, National Institute of Allergy and Infectious Diseases (grant no. 1R03AI166406-01); a grant from the Southeast Center for Agricultural Health and Injury Prevention, and from the Department of the Army, U.S. Army Contracting Command, Aberdeen Proving Ground, Natick Contracting Division, Ft Detrick MD. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the position or the policy of the Government and no official endorsement should be inferred.

- kulikowski -

Note to editors: The abstract of the paper follows.

“Detection of Orientia Spp. Bacteria in Field-Collected Free-Living Eutrombicula Chigger Mites, USA”

Authors: Kaiying Chen, Nicholas V. Travanty, Charles S. Apperson, R. Michael Roe, and Loganathan Ponnusamy, North Carolina State University; Reuben Garshong and Gideon Wasserberg, University of North Carolina Greensboro; Dac Crossley, Georgia Museum of Natural History

Published: July 12, 2023 in Emerging Infectious Diseases

DOI: 10.3201/eid2908.230528 

Abstract: Scrub typhus, a rickettsial disease caused by Orientia spp., is transmitted by infected larval trombiculid mites (chiggers). We report the molecular detection of Orientia species in free-living Eutrombicula chiggers collected in an area in North Carolina, United States, in which spotted fever group rickettsiae infections are endemic.

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JOURNAL

Emerging Infectious Diseases

DOI

10.3201/eid2908.230528 

METHOD OF RESEARCH

Observational study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Detection of Orientia Spp. Bacteria in Field-Collected Free-Living Eutrombicula Chigger Mites, USA

ARTICLE PUBLICATION DATE

12-Jul-2023

Could drops replace eye injections for retina disease?

Peer-Reviewed Publication

COLUMBIA UNIVERSITY IRVING MEDICAL CENTER

NEW YORK, NY-- A new study suggests that eye drops developed by Columbia University researchers could be a more effective–and comfortable–therapy for a common eye disease currently treated with injections into the eye.

Retinal vein occlusion (RVO), an eye disease that affects up to 2% of people over age 40, occurs when a vein in the eye’s retina becomes blocked, leading to swelling in the eye, inflammation, damage to the retina, and vision loss. 

Standard therapy involves injecting into the eye a vascular endothelial growth factor inhibitor (anti-VEGF) that reduces swelling. The therapy can improve vision but patients with significant retinal damage due to impaired blood flow often have poor outcomes.

“Anti-VEGF therapy has helped a lot of people with RVO, but the fear factor—having to get a needle in the eye—causes many people to delay treatment, which can lead to retinal damage,” says Carol M. Troy, MD, PhD, professor of pathology & cell biology and of neurology at Columbia University Vagelos College of Physicians and Surgeons. “There’s an opportunity to help more people with this disease that is a leading cause of blindness worldwide.”

The study found that an experimental eye drop treatment was twice as effective as the standard injection therapy at reducing swelling and improving blood flow within the retina of mice with RVO. The eye drops also prevented neurons (photoreceptors) in the retina from deteriorating and preserved visual function over time, whereas the standard injections had no effect on either. 

Eye drops target ‘death enzyme’

The eye drops contain an experimental drug that blocks caspase-9, an enzyme that triggers cell death, and was found by Troy’s lab to be overactive in blood vessels injured by RVO. 

“We think the eye drops improve the health of blood vessels in the retina, which then decreases the toxic signaling that damages the retina’s neurons and leads to vision loss,” says Maria I. Avrutsky, PhD, the study’s first author who conducted the research as a postdoc in the Troy lab.

Future studies are aimed at preparing to test the eye drops in human clinical trials and identifying additional therapeutic targets. 

“Finding the root cause of RVO is the holy grail, but if we can at least provide better symptomatic relief that doesn’t distress patients, it would be a really good start,” Troy says. 

More information

The study, “Caspase-9 inhibition confers stronger neuronal and vascular protection compared to VEGF neutralization in a mouse model of retinal vein occlusion,” was published online in Frontiers of Neuroscience. 

All authors: Maria I. Avrutsky (Columbia, now at Character Biosciences), Claire W. Chen (Columbia), Jacqueline M. Lawson (Columbia), Scott J. Snipas (Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA) Guy S. Salvesen (Sanford Burnham Prebys), and Carol M. Troy (Columbia).

The study was supported by a sponsored research agreement with Opera Therapeutics and grants from the National Institutes of Health (R01NS091333 and T32EY013933) and the Department of Defense Army/Air Force. 

Carol Troy and Maria Avrutsky are inventors on patent applications filed by Columbia University related to the therapeutic use of caspase-9 inhibitors. Maria Avrutsky received consulting income from Opera Therapeutics.

The other authors report no financial or other conflicts of interest.

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Columbia University Irving Medical Center (CUIMC) is a clinical, research, and educational campus located in New York City. Founded in 1928, CUIMC was one of the first academic medical centers established in the United States of America. CUIMC is home to four professional colleges and schools that provide global leadership in scientific research, health and medical education, and patient care including the Vagelos College of Physicians and Surgeons, the Mailman School of Public Health, the College of Dental Medicine, the School of Nursing. For more information, please visit cuimc.columbia.edu.

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JOURNAL

Frontiers in Neuroscience

DOI

10.3389/fnins.2023.1209527 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Caspase-9 inhibition confers stronger neuronal and vascular protection compared to VEGF neutralization in a mouse model of retinal vein occlusion

ARTICLE PUBLICATION DATE

28-Jun-2023

COI STATEMENT

Carol Troy and Maria Avrutsky are inventors on patent applications filed by Columbia University related to the therapeutic use of caspase-9 inhibitors. Maria Avrutsky received consulting income from Opera Therapeutics.