Honey bees live in dynamic communities and constantly communicate with each other using chemicals that serve as social cues. For example, nurse bees — that are responsible for taking care of larvae that ultimately become queens and worker bees — constantly monitor the larvae using in the dark using pheromones. The larvae emit brood pheromones to indicate that they need food. There are also alarm pheromones that workers produce to warn the other bees of danger. If these cues are dampened or not perceived properly, the colony may fail to thrive.

Since 2007, scientists have known that honey bees have been in trouble. One of the stressors that have raised concerns are insecticides, which affect honey bee health. Because these are usually used in combination with other chemicals, the resulting mixture can become unexpectedly toxic to bees.

“For many years, it was assumed that fungicides do not have an adverse impact on insects because they are designed for fungal targets,” said May Berenbaum (GEGC/IGOH), a professor of entomology. “Surprisingly, in addition to insecticides, fungicides also have an adverse effect on bees and combining the two can disrupt colony function.”

For more than a decade, reports originating from almond orchards, where two-thirds of the U.S. honey bees are transported every year when the flowers are in bloom, implicated pesticide spray mixtures. In particular, the problem lies in the use of supposedly inactive chemicals called adjuvants, which increases the “stickiness” of the insecticide so it stays on the plants.

Because adjuvants have long been considered to be biologically benign, they are not subject to the same level of safety testing as other insecticidal agents. “Recently, researchers have shown that adjuvants alone or when used in combination with fungicides and insecticides are toxic to bees,” Berenbaum said.

Nurse bees are especially vulnerable to these combinations. “The health of the queens is paramount,” Berenbaum said. “If healthy queens are not produced, the colony can suffer.”

To understand how combinations affect nurse bees, the researchers tested their effect on the olfactory system of honey bees using the adjuvant Dyne-Amic, the fungicide Tilt, and the insecticide Altacor.

The researchers divided bees into four groups of ten bees and for a week exposed them to either untreated commercial pollen or to pollen that had been treated with either Dyne-Amic, or Tilt and Altacor, or all three together. The bees were then anesthetized on ice and one antenna was carefully removed from each bee. The researchers then exposed the antenna to chemical mimics of brood and alarm pheromones and recorded the antenna’s response using a technique called electroantennography.

With this method, Ling-Hsiu Liao, a research scientist, and Wen-Yen Wu, a graduate student, in the Berenbaum lab, found that when nurse bees had consumed pollen contaminated by the three chemicals, their antennal responses to some brood pheromones and alarm pheromones were altered. Their finding suggests that these commonly-used pesticides can interfere with honey bee communication.

How these chemicals interact and influence the bees is still unclear. “There are many possible explanations for how consuming these chemicals can affect the sensory responses of bees,” Liao said. “The antenna detects and triggers the response to olfactory signals. In this study we did not look at what other changes are triggered, particularly changes in behavior.”

In addition to parsing out the underlying molecular pathways that are affected, the researchers are also interested in testing other mixtures of commonly used pesticides as well as looking at the response of bees in other populations. They hope that their work can help beekeepers rethink how they manage and protect their colonies.

Instead, researchers from Dartmouth and the University of St. Andrews in Scotland report that the eyes of Rudolph and his reindeer brethren may have evolved so that they can spot their favorite food during dark and snowy Arctic winters, according to a new study in the journal i-Perception.

The findings help explain the long-standing scientific mystery as to why reindeer can see light in the ultraviolet (UV) spectrum — and add intrigue to the smiling airborne ungulates popularized in the classic story by 1926 Dartmouth graduate Robert L. May.

“Reindeer are so cool, but many people think about them only at Christmas,” Nathaniel Dominy, first author of the study and the Charles Hansen Professor of Anthropology at Dartmouth says. “Now is a good time to alert people to their extraordinary visual system.”

Reindeer subsist primarily on reindeer moss, or Cladonia rangiferina, which isn’t a moss but actually a species of algae-fungus fusion known as lichen. C. rangiferina forms thick crunchy carpets across northern latitudes and is so integral to the survival of reindeer that even its formal name stems from the scientific term for reindeer, Rangifer.

The researchers worked in the Cairngorms mountains in the Scottish Highlands, which host Britain’s only reindeer herd — reintroduced from Scandinavia after being hunted to extinction locally — and more than 1,500 species of lichen. Despite these options, reindeer in the Cairngorms rely on C. rangiferina during the winter.

“A peculiar trait of reindeer is their reliance on this one type of lichen,” Dominy says. “It’s unusual for an any animal to subsist so heavily on lichens, let alone such a large mammal.”

To the human eye, the white lichen is invisible against the snowy backdrop of an Arctic winter.

But Dominy and co-authors Catherine Hobaiter and Julie Harris from St. Andrews discovered that C. rangiferina and a few other lichen species that supplement the reindeer diet absorb UV light. Spectral data from the lichen and light filters calibrated to mimic reindeer vision revealed that these organisms appear to reindeer as dark patches against an otherwise brilliant landscape, making them easier to locate.

“Getting a visual approximation of how reindeer might see the world is something other studies haven’t done before,” says Dominy, who published a paper in 2015 on how Rudolph’s red nose would’ve acted as an effective foglamp in the haze of winter.

“If you can put yourself in their hooves looking at this white landscape, you would want a direct route to your food,” he says. “Reindeer don’t want to waste energy wandering around searching for food in a cold, barren environment. If they can see lichens from a distance, that gives them a big advantage, letting them conserve precious calories at a time when food is scarce.”

Previous research has shown that reindeer eyes change between summer and winter, Dominy says. Their tapetum — the light-enhancing membrane that gives many animals “shiny” eyes — transitions in winter from the golden color most animals have to a vivid blue that is thought to amplify the low light of polar winter.

“If the color of the light in the environment is primarily blue, then it makes sense for the eye to enhance the color blue to make sure a reindeer’s photoreceptors are maximizing those wavelengths,” Dominy says.

But the blue tapetum also lets up to 60% of ultraviolet light pass through to the eye’s color sensors. That means that reindeer see the winter world as a shade of purple, similar to how a person would see a room with a black light — UV-reflecting surfaces such as snow shine brightly while UV-absorbing surfaces are starkly dark.

The researchers recount how scientists have sought to answer why the eyes of an Arctic animal that is active during the day would be receptive to the UV light that would be reflecting off of every snow-covered surface. But their study suggests that the answer is tied to what UV light doesn’t reflect from — C. rangiferina and other bushy lichens.

Given the importance of lichens in the reindeer diet, the researchers report, it is possible that the animal’s eyes are optimized to single out this food staple at the time of year it would be most difficult to find.

So, while the luminescent nose of the most famous reindeer of all “may light the way for Santa to see by,” the researchers write, “it is Rudolph’s blue eyes that allow him to find dinner after a long Christmas season.”

Joanna Marroquin, a Mason PhD in Public Health student, and Associate Professor Anna Pollack, reviewed studies conducted since 2103 that measured chemicals in menstrual products and that measured human biomarkers of chemical exposure and determined that endocrine-disrupting chemicals were found in menstrual products including tampons, pads, and liners.

“Identifying chemicals in menstrual products that menstruators regularly use is important because exposure through these products can impact menstruators’ reproductive health,” said Marroquin, the paper’s first author.

The study found that menstrual products contain a variety of endocrine-disrupting chemicals including phthalates, volatile organic compounds, parabens, environmental phenols, fragrance chemicals, dioxins and dioxin-like compounds.

This issue is even more relevant thanks to the Robin Danielson Menstrual Product and Intimate Care Product Safety Act of 2023, which was introduced in the U.S. House of Representatives in October 2023. The Act would establish a program of research regarding the risks posed by the presence of dioxins, phthalates, pesticides, chemical fragrances, and other components in menstrual products and intimate care products.

This literature reviewed 15 papers published between 2013 and 2023 that tested menstrual products in the U.S., Japan, and South Korea. The researchers note that there are few publications available that measure chemicals in menstrual products.

Additionally, though forever chemicals (PFAS) have been found in menstrual underwear, there is a lack of peer-reviewed research on menstrual underwear and other newly-popular-in-the-U.S. products such as menstrual cups and discs.

Chemicals in menstrual products: A systematic review was published in BJOG, an international journal of obstetrics and gynecology in September 2023. Additional authors include Marianthi-Anna Kiomourtzoglou from Mailman School of Public Health, Columbia University and Alexandra Scranton from Women’s Voices for the Earth.

The research was supported by Pollack’s National Institute of Environmental Health Sciences R01ES31079 award.

The study, published this week in the journal Environmental Health Perspectives, also noted an association between preconception exposure to phthalates and changes in women’s reproductive hormones, as well as increased inflammation and oxidative stress.

“Phthalates are ubiquitous endocrine disruptors and we’re exposed to them every day,” says lead author Carrie Nobles, assistant professor of environmental health sciences in the School of Public Health and Health Sciences.

Phthalates are found in such common products as shampoo, makeup, vinyl flooring, toys and medical devices. People are exposed primarily by ingesting food and liquid that has come in contact with products containing the chemicals, according to a Centers for Disease Control and Prevention fact sheet.

Nobles and team analyzed data from a “unique cohort” of women in the preconception time-to-pregnancy study known as EAGeR (Effects of Aspirin in Gestation and Reproduction), which evaluated the effect of low-dose aspirin on live-birth rates. The study includes detailed information on 1,228 participants during six menstrual cycles when they are attempting to get pregnant. The women who became pregnant were followed through pregnancy.

“We were able to look at some environmental exposures like phthalates and how that relates to how long it takes to get pregnant. There was detailed data for each menstrual cycle, so we had a good handle on the date of ovulation and the timing of pregnancy when that happened,” Nobles says.

The body breaks down phthalates into metabolites that are excreted in urine and can be analyzed. The researchers measured 20 phthalate metabolites in urine samples taken when the participants enrolled in the study.

“We found there were three parent compounds that seem to be most strongly associated with taking longer to get pregnant, although we saw a general trend toward it taking longer to get pregnant across the phthalates we looked at,” Nobles says. “As exposure got higher, we saw more and more of an effect.”

The researchers also looked at a global marker of inflammation, C-reactive protein, and found the women who had higher levels of phthalates exposure also had higher levels of inflammation and oxidative stress, which can lead to organ and tissue damage and ultimately to disease.

In addition, women who showed higher levels of phthalates had lower estradiol and higher follicle-stimulating hormone across the menstrual cycle, which play an important role in ovulation and the early establishment of pregnancy.

“This profile — estradiol staying low and follicle-stimulating hormone staying high — is actually something that we see in women who have ovarian insufficiency, which can happen with age as well as due to some other factors,” Nobles says. “Ovulation just isn’t happening as well as it used to.”

While women can check consumer product labels and look for phthalate-free options, the ubiquitous nature of the chemicals makes it difficult for an individual to control their exposure.

In Europe, certain phthalates are banned or severely restricted in their use, but the U.S. has no formal prohibitions. Nobles says the research findings add to the evidence that phthalates exposures have a negative impact on women’s reproductive health and can be used to help inform policy making.

“Maybe we want to think differently about our regulatory system and how we identify important exposures that are having adverse effects on whether people can get pregnant and have a healthy pregnancy,” Nobles says.

Over the past few decades, hydrogels have received a lot of attention for treating skin wounds. When applied over a lesion, these special gels can promote healing by absorbing discharged fluids (exudates) and keeping the wound protected, well-hydrated, and oxygenated.

However, most developed hydrogels are given adhesive properties to skin tissue to follow skin movement. Since these hydrogels are sticky and adhere to the skin and wound site, they stretch and expand the wound itself once they swell up after absorbing exudates. This not only causes pain to the user but also puts them at a higher risk of bacterial infection due to the wound area expansion. Therefore, in order to create hydrogels that can effectively treat wounds without interfering with the wound healing process, it is necessary to experiment with the preparation of hydrogels based on new ideas while utilizing existing material properties.

Against this backdrop, a team of researchers from Tokyo University of Science (TUS), Japan, have now proposed an innovative and highly-value added medical material for treating skin wounds. As reported in their recent study published in the International Journal of Biological Macromolecules, they developed a novel, low-cost hydrogel using a component found in seaweed, achieving physical properties completely different from those of conventional hydrogels. The study, which was made available online on 8 November 2023, and will be published in Volume 254, Part 3 of the journal in January 2024, was led by Mr. Ryota Teshima, a Master’s student at TUS. Assistant Professor Shigehito Osawa, Ms. Miki Yoshikawa, Associate Professor Yayoi Kawano, Professor Hidenori Otsuka, and Professor Takehisa Hanawa, all from different faculties and departments at TUS, were also a part of this study.

The method of preparation of the proposed hydrogel is quite straightforward. It was made using alginate, calcium carbonate, and carbonated water. Alginate is a biocompatible substance that can be extracted from beach-cast seaweed. Most importantly, it does not adhere strongly to cells or skin tissues. Thanks to the special structure formed by alginate and calcium ions, in addition to the protective effect of the CO₂ in carbonated water against acidification, the resulting hydrogel not only exhibited ideal pH and moisture conditions for wound recovery but also demonstrated significantly lower adhesion and swelling, compared to other commercial hydrogel wound dressings.

The researchers tested the effectiveness of their new hydrogel using cell cultures and a mouse model, both of which yielded excellent results. “Through animal experiments, we demonstrated that our hydrogel has a high therapeutic effect and at the same time can suppress the temporary expansion of the wound area caused by conventional clinical preparations,” remarks Mr. Teshima. “This proves our initial hypothesis that gels with low skin adhesion and low-swelling properties are excellent as wound dressing materials, which is the complete opposite of conventional wisdom.”

Worth noting, alginate can be extracted from beach-stranded seaweed, a renewable resource that is often regarded as a coastal waste material. Since the proposed hydrogel is not only inexpensive but also biodegradable, this development marks an important step towards future progress on sustainable medicine. “Medical materials still lack a sustainability-oriented perspective, and we believe this research will serve as a benchmark for the design of future medical materials and lead to sustainable and low-cost wound care,” says Mr. Teshima. “Moreover, our findings can help clarify issues with hydrogel formulations currently in clinical use and provide new design guidelines for next-generation wound treatment gels.”

The team used CRISPR gene editing technologies to knock out the cytoglobin gene in zebrafish. The lack of cytoglobin caused the development of embryos with a mirrored heart, meaning the heart had a reversed left-right pattern. In humans, cytoglobin is involved in processes involving nitric oxide, a compound that helps regulate healthy blood flow to organs. Study co-senior author Mark T. Gladwin, MD, the John Z. and Akiko K. Bowers Distinguished Professor and Dean, University of Maryland School of Medicine, and Vice President for Medical Affairs, University of Maryland, Baltimore, has been researching the effects of nitric oxide on blood vessels for more than 20 years including in this recent study finding.

“Since its discovery two decades ago, cytoglobin has been found to be expressed in nearly all human tissues, but the mechanisms of how this protein functions were largely unknown,” said Dr. Gladwin. “We know that cytoglobin can play a role in modulating and maintaining nitric oxide levels, but our new finding indicates that it positively regulates NO production to ensure proper cilia function and its absence can lead to major laterality abnormalities of organs.”

To conduct the study, the research team knocked out the gene for cytoglobin in zebrafish and were amazed to see that it led to dramatic defects in the structure and location of organs in developing embryos. The heart, for example, was located on the right side of the fish instead of the left with a looping to the left instead of the right.

“We found that cytoglobin plays a vital role in the structure and function of tiny hair-like structures called cilia, which determine the asymmetry and proper development of organs,” said study senior author Paola Corti, PhD, Assistant Professor of Biochemistry and Molecular Biology at UMSOM.

This is the first time cytoglobin — or any of the globin proteins like hemoglobin — has been found to be involved in fetal development and that a paucity could be linked to birth defects. It’s also the first time that cytoglobin has been linked to cilia function. Such a finding could open the door for the development of therapeutics for rare birth defects that affect the movement of cilia.

About 1 in every 10,000 to 30,000 people are born with Primary Ciliary Dykinesia (PCD), a rare disease that affects the cilia and can cause breathing issues from thickened mucus clogging airways. “Kartagener’s syndrome is a form of PCD and is known to cause the type of heart defects seen in the zebrafish where the heart is abnormally positioned to the right and rotated,” said Dr. Corti. “There is no cure for this condition, just surgery to fix any heart defects and treatments to manage symptoms.”

While certain genes have been identified that are known to cause about 70 percent of PCD cases, cytoglobin could play a key role in the 30 percent of cases with no known genetic cause.

“We found the phenotype and connected the dots to cilia. In the presence of cytoglobin, we could track the function of the protein and how if led to proper cilia function and organ development. In the absence, we saw these defects,” said Elizabeth Rochon, PhD, first author of the study and Assistant Professor of Medicine at UMSOM.

Funding for the study was from the National Institutes of Health, the American Heart Association, and the Institute for Transfusion Medicine and the Hemophilia Center. UMSOM faculty co-authors include Anthony W. DeMartino, PhD, Assistant Professor of Medicine, and Qinzi Xu, MD, Assistant Professor of Medicine.

Other co-authors included faculty at the University of Pittsburgh School of Medicine and the University of Copenhagen in Denmark.

The new study comparing the viruses that cause COVID-19 and the flu also revealed that in the 18 months after infection, patients hospitalized for either COVID-19 or seasonal influenza faced an increased risk of death, hospital readmission, and health problems in many organ systems. Further, the time of highest risk was 30 days or later after initial infection.

“The study illustrates the high toll of death and loss of health following hospitalization with either COVID-19 or seasonal influenza,” said senior author Ziyad Al-Aly, MD, a clinical epidemiologist at Washington University. “It’s critical to note that the health risks were higher after the first 30 days of infection. Many people think they’re over COVID-19 or the flu after being discharged from the hospital. That may be true for some people. But our research shows that both viruses can cause long-haul illness.”

The findings are published Dec. 14 in The Lancet Infectious Diseases.

The statistical analysis spanned up to 18 months post-infection and included a comparative evaluation of risks of death, hospital admissions and 94 adverse health outcomes involving the body’s major organ systems.

“A review of past studies on COVID-19 versus the flu focused on a short-term and narrow set of health outcomes,” said Al-Aly, who treats patients within the VA St. Louis Health Care System and is an assistant professor of medicine at Washington University. “Our novel approach compared the long-term health effects of a vast array of conditions. Five years ago, it wouldn’t have occurred to me to examine the possibility of a ‘long flu.’ A major lesson we learned from SARS-CoV-2 is that an infection that initially was thought to only cause brief illness also can lead to chronic disease. This revelation motivated us to look at long-term outcomes of COVID-19 versus flu.

“We wanted to know whether and to what degree people with flu also experience long-term health effects,” Al-Aly said. “The big answer is that both COVID-19 and the flu led to long-term health problems, and the big aha moment was the realization that the magnitude of long-term health loss eclipsed the problems that these patients endured in the early phase of the infection. Long COVID is much more of a health problem than COVID, and long flu is much more of a health problem than the flu.”

However, the overall risk and occurrence of death, hospital admissions, and loss of health in many organ systems are substantially higher among COVID-19 patients than among those who have had seasonal influenza, Al-Aly said. “The one notable exception is that the flu poses higher risks to the pulmonary system than COVID-19,” he said. “This tells us the flu is truly more of a respiratory virus, like we’ve all thought for the past 100 years. By comparison, COVID-19 is more aggressive and indiscriminate in that it can attack the pulmonary system, but it can also strike any organ system and is more likely to cause fatal or severe conditions involving the heart, brain, kidneys and other organs.”

The researchers analyzed de-identified medical records in a database maintained by the U.S. Department of Veterans Affairs, the nation’s largest integrated health-care delivery system. They evaluated information involving 81,280 patients hospitalized for COVID-19 at some point from March 1, 2020, through June 30, 2022, as well as 10,985 patients hospitalized for seasonal influenza at some point from Oct. 1, 2015, through Feb. 28, 2019.

Patients represented multiple ages, races and sexes.

Regarding both viruses, patient vaccination status did not affect results. Those in the COVID-19 cohort were hospitalized during the pre-delta, delta and omicron eras.

During the overall 18-month study period, patients who had COVID-19 faced a 50% higher risk of death than those with seasonal influenza. This corresponded to about eight more deaths per 100 persons in the COVID-19 group than among those with the flu.

Although COVID-19 showed a greater risk of health loss than seasonal influenza, infection with either virus carried significant risk of disability and disease. The researchers found COVID-19 exhibited increased risk of 68% of health conditions examined across all organ systems (64 of the 94 adverse health outcomes studied), while the flu was associated with elevated risk of 6% of health conditions (six of the 94) — mostly in the respiratory system.

Also, over 18 months, COVID-19 patients experienced an increased risk of hospital readmission as well as admission to an intensive care unit (ICU). For every 100 persons in each group, there were 20 more hospital admissions and nine more ICU admissions in COVID-19 than flu.

“Our findings highlight the continued need to reduce the risk of hospitalization for these two viruses as a way to alleviate the overall burden of health loss in populations,” Al-Aly said. “For both COVID-19 and seasonal influenza, vaccinations can help prevent severe disease and reduce the risk of hospitalizations and death. Optimizing vaccination uptake must remain a priority for governments and health systems everywhere. This is especially important for vulnerable populations such as the elderly and people who are immunocompromised.”

In both COVID-19 and the flu, more than half of death and disability occurred in the months after infection as opposed to the first 30 days, the latter of which is known as the acute phase.

“The idea that COVID-19 or flu are just acute illnesses overlooks their larger long-term effects on human health,” Al-Aly said. “Before the pandemic, we tended to belittle most viral infections by regarding them as somewhat inconsequential: ‘You’ll get sick and get over it in a few days.’ But we’re discovering that is not everyone’s experience. Some people are ending up with serious long-term health issues. We need to wake up to this reality and stop trivializing viral infections and understand that they are major drivers of chronic diseases.”