It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Thursday, May 01, 2025
Sex- and race-specific prevalence of hearing loss across the adult lifespan and associated factors
About The Study: The prevalence and degree of hearing loss were highest among white male individuals and lowest among Black female individuals in this cohort study of 1,787 adults. Some factors associated with hearing loss, including noise exposure, differed across sex-specific and race-specific groups. Hearing loss is an important public health concern that could be addressed through tailored interventions to reduce its risk across populations.
Corresponding Author: To contact the corresponding author, Lauren K. Dillard, PhD, AuD, email dillalau@musc.edu.
Editor’s Note: Please see the article for additional information, including other authors, author contributions and affiliations, conflict of interest and financial disclosures, and funding and support.
· UCLA and UCSD scientists inserted DNA-encoding methylmercury detoxification enzymes into the genome of an abundant human gut bacterium. The engineered bacterium detoxified methylmercury in the gut of mice and dramatically reduced the amount that reached other tissues, such as the brain and liver.
· Mice given an oral probiotic containing the engineered microbe and fed a diet high in bluefin tuna had much lower methylmercury levels than expected, suggesting that a probiotic might eventually make it safer for people to consume fish.
· Researchers performed the tests using pregnant mice and found lower levels of methylmercury in both maternal and fetal tissues, and lower signs of mercury toxicity in the fetal brain.
UCLA and UCSD scientists inserted DNA-encoding methylmercury detoxification enzymes into the genome of an abundant human gut bacterium. The engineered bacterium detoxified methylmercury in the gut of mice and dramatically reduced the amount that reached other tissues, such as the brain and liver.
Mice given an oral probiotic containing the engineered microbe and fed a diet high in bluefin tuna had much lower methylmercury levels than expected, suggesting that a probiotic might eventually make it safer for people to consume fish.
Researchers performed the tests using pregnant mice and found lower levels of methylmercury in both maternal and fetal tissues, and lower signs of mercury toxicity in the fetal brain.
An engineered gut microbe can detoxify methylmercury, reducing the amount that passes into the brain and developing fetuses of mice fed a diet rich in fish, UCLA and UC San Diego’s Scripps Institution of Oceanography scientists have discovered.
“We envision the possibility that people could take a probiotic to offset the risk of consuming too much methylmercury, especially when pregnant,” said UCLA associate professor and director of the UCLA Goodman-Luskin Microbiome Center Elaine Hsiao, who is the senior author of a paper describing the research in the journal Cell Host & Microbe.
Mercury is a pollutant that enters water from several sources, the largest of which are human activities such as coal burning, artisanal gold mining and smelting, and wastes
from consumer products. In the ocean, mercury transforms into a toxic form called methylmercury. It also biomagnifies, meaning that methylmercury concentrations in animal tissues increase up the food chain from algae-eaters to top predators like humans.
This means that all the methylmercury in something an organism eats goes into its tissues and is passed on to whatever eats it. Organisms near the top of their food chains, like bluefin tuna and humans, acquire all the mercury accumulated by the previous links in the chain. Thus, people who primarily eat food containing high mercury levels are at higher risk of mercury poisoning and birth defects.
“Despite global efforts to reduce mercury emissions and its accumulation in fish, methylmercury levels in seafood are not expected to decline anytime soon. Fish remains a major and culturally important part of the diet for many people around the world and we hope it continues to be,” said co-senior author and Scripps associate professor of marine biogeochemistry Amina Schartup.
Researchers modified Bacteroides thetaiotaomicron, a naturally abundant bacterium in the human digestive tract, by inserting DNA-encoding mercury detoxification enzymes from a mercury-resistant soil bacterium. After confirming that the engineered bacteria could clear methylmercury in a test tube, they replaced the natural gut microbiomes of mice with the modified bacteria and orally administered a large amount of methylmercury all at once. The mice had lower levels of methylmercury in their intestines just three hours after, and the level continued to fall for four days, showing that the bacteria helped to effectively eliminate the methylmercury in the intestine.
They next asked whether the engineered bacteria would be effective at decreasing tissue methylmercury levels when exposure occurs gradually through routine dietary intake. To test this, the researchers fed the mice diets containing bluefin tuna over a period of days and found that not only did the bacteria reduce mercury in the intestine just as well, but less entered the brain and liver, too.
They then tested pregnant mice and found lower levels of methylmercury in both maternal and fetal tissues, and lower signs of mercury toxicity in the fetal brain.
“By reducing dietary methylmercury in the intestine, the gut bacteria helped to eliminate it from the body before it could enter the maternal bloodstream and access the developing offspring,” said first author and UCLA research scientist Kristie Yu.
Co-author and UCLA researcher Franciscus Chandra said that the lowered signs of toxicity in the fetal brain showed that the bacterium works at levels that are biologically meaningful.
When the team repeated the experiments with salmon, which contains lower levels of methylmercury than in bluefin tuna, the bacterium was also effective.
Finally, they fed the bacteria as an oral probiotic to mice with intact microbiomes and fed them the same bluefin tuna diet as the mice in the previous experiment. Under these conditions, the engineered bacteria were also remarkably effective at minimizing the amount of methylmercury that entered tissues, suggesting that one day, a probiotic could be developed to reduce the risks of a fish-based diet.
The researchers were supported by funds from the Eunice Kennedy Shriver National Institute of Child Health and Human Development; the National Institute of Environmental Health Sciences; the National Science Foundation; the Research Corporation for Science Advancement; the Simons Foundation; and the Packard Foundation.
Hsiao and Schartup are working on improving the efficacy of the bacterium and moving closer to translation to humans, an endeavor for which continued federal funding is critical.
Journal
Cell Host & Microbe
Ptero firma: Footprints pinpoint when ancient flying reptiles conquered the ground
Study led by the University of Leicester links fossilised flying reptile tracks to animals that made them
Fossils of footprints over 160 million years old have helped palaeontologists at the University of Leicester to narrow down when pterosaurs adapted to live on the ground.
These awe-inspiring flying reptiles of the Mesozoic era are often imagined soaring over the heads of dinosaurs. But new research shows that some of these ancient creatures were just as comfortable walking on the ground.
In a groundbreaking new study published today in Current Biology (1 May), scientists at the University of Leicester have successfully linked fossilised footprints to the types of pterosaurs that produced them. By using 3D modelling, detailed analysis, and comparisons with pterosaur skeletons, the team has shown that at least three different types of tracks match up with distinct groups of pterosaurs.
The new study supports the idea that pterosaurs underwent a major ecological shift during the middle part of the Age of Dinosaurs, about 160 million years ago, with several groups becoming more terrestrial.
Lead author Robert Smyth, a doctoral researcher in the in the Centre for Palaeobiology and Biosphere Evolution (School of Geography, Geology and the Environment at the University of Leicester), explained: “Footprints offer a unique opportunity to study pterosaurs in their natural environment. They reveal not only where these creatures lived and how they moved, but also offer clues about their behaviour and daily activities in ecosystems that have long since vanished.”
The study uncovered three distinct types of pterosaur footprints, each shedding light on different lifestyles and behaviours. By linking footprints to specific groups, scientists now have a powerful new way to study how these flying reptiles lived, moved, and adapted to different ecosystems across time.
Co-author Dr David Unwin from the School of Museum Studies, University of Leicester explained: "Finally, 88 years after first discovering pterosaur tracks, we now know exactly who made them and how."
Perhaps the most striking discovery comes from a group of pterosaurs called neoazhdarchians which includes Quetzalcoatlus, with a 10 m wingspan one of the largest flying animals ever to have existed. Their footprints have been found in coastal and inland areas around the world, supporting the idea that these long-legged creatures not only dominated the skies but were also frequent ground dwellers, inhabiting the same environments as many dinosaur species. Some of these tracks are present right up until the asteroid impact event, 66 million years ago, which led to the extinction of both pterosaurs and dinosaurs.
One group of pterosaurs, ctenochasmatoids, known for their long jaws and needle-like teeth, left behind tracks most commonly found in coastal deposits. These animals likely waded along muddy shores or in shallow lagoons, using their specialised feeding strategies to catch small fish or floating prey. The abundance of these tracks suggests that these coastal pterosaurs were far more common in these environments than their rare bodily remains indicate.
Another type of footprint was discovered in rock layers that also preserve the fossilised skeletons of the same pterosaurs. The close association between the footprints and skeletons provides compelling evidence for identifying the print makers. Known as dsungaripterids, these pterosaurs had powerful limbs and jaws, with toothless, curved beak tips designed for prising out prey, while large, rounded teeth at the back of their jaws were perfect for crushing shellfish and other tough food items.
Smyth explains: "Tracks are often overlooked when studying pterosaurs, but they provide a wealth of information about how these creatures moved, behaved, and interacted with their environments. By closely examining footprints, we can now discover things about their biology and ecology that we can't learn anywhere else."
Pterosaur tracks meet their match. Where ancient footprints meet their maker. A side-by-side comparison of a pterosaur’s hand and foot with 155-million-year-old tracks from Wyoming, USA. The false-colour depth map reveals the shape and pressure of each step, showing that these creatures bore more weight on their hands while walking.
Credit
Source: University of Leicester
Pterosaur tracks meet their match. Where ancient footprints meet their maker. A side-by-side comparison of a pterosaur’s hand and foot with 155-million-year-old tracks from Wyoming, USA. The false-colour depth map reveals the shape and pressure of each step, showing that these creatures bore more weight on their hands while walking.
Binghamton University political scientsits Daniel Magleby and Michael D. McDonald explore different methods to evaluate possible gerrymanders and their tradeoffs in “Assessing Gerrymandering after the 2020 Census,” which recently appeared in Election Law Journal.
Credit: "Vote here, vote aqui" by whiteafrican is licensed under CC BY 2.0. https://openverse.org/image/1ec2e987-7fcc-46c5-b148-206deb5f7fbd?q=voting&p=32
When you’re ill, medical professionals will run tests and make a diagnosis, gearing your medical treatment to what ails you. After all, heart attacks and bacterial infections can both kill — but testing and treating a patient with clear symptoms of a heart attack for strep doesn’t solve the problem.
The same holds true for gerrymandered electoral districts, according to Binghamton University political science researchers. Think of a gerrymander as a form of illness, Binghamton University, State University of New York Associate Professor Daniel B. Magleby explained — a sick map, in effect.
“Understanding and applying the right diagnostic tools allows us to understand what values the map is violating — how it’s sick in a particular way,” he explained.
Magleby and Professor Michael D. McDonald explore different methods to evaluate possible gerrymanders and their tradeoffs in “Assessing Gerrymandering after the 2020 Census,” which recently appeared in Election Law Journal.
The U.S. Constitution requires a census every 10 years to officially count the country’s population; at the conclusion of that census, the lines of Congressional districts are redrawn — sometimes in ways that distort the principles of fair elections.
Gerrymandering is an old phenomenon coined by Elbridge Gary in 1812; the term originally referred to the strange shapes imposed on districts to distort electoral outcomes.
However, gerrymandering has been getting more sophisticated and has worsened since the 1950s, McDonald said. While advances and statistical analysis have led to better tools for diagnosing distortions, these same tools can also help execute them.
“We’re in a bit of an arms race,” Magleby acknowledged.
The values behind fair elections
A 2019 U.S. Supreme Court decision pushed efforts to limit gerrymanders out of the federal courts to the realm of politics and willing state courts. Reformers feared the decision would ultimately make it impossible to police gerrymandering practices.
That hasn’t proven to be the case so far.
“Congress, in anticipation of what the Roberts Court was going to do, started to float ideas about how to write rules that would police gerrymandering, McDonald said. “It looks pretty clear that the Republicans don’t want to do that, but if the Democrats had a solid majority, they might enact legislation.”
In their analysis, McDonald and Magleby applied five methods proposed by scholars to detect gerrymanders to 37 states with three or more congressional districts, using congressional maps enacted after the 2020 census. They found consistent evidence of partisan gerrymandering in four states, consistent evidence of no partisan gerrymandering in 12 states, and mixed evidence in the remaining 21.
A key problem: the methods of analysis target different types of gerrymandering.
“You have to identify the values you want to preserve, and then a diagnostic will follow,” McDonald said. “Those values cannot be so vague as ‘fairness.’”
State legislatures often play a major role in drawing district lines, which can be problematic in states dominated by a single political party. Nonpartisan or bipartisan redistricting commissions are one answer, but research by McDonald, Magleby and their colleagues shows that such commissions can also result in gerrymanders.
Adding to the complexity: manipulation isn’t always negative. Sometimes, district lines must be adjusted to preserve majority rule or to make sure that minority interests are included in the system. Consider New York and Illinois, two states that have a majority of Democratic voters — who tend to cluster in urban areas. If you draw districts based strictly on geography, you will end up excluding the majority of voters from representation based on where they live.
Their solution is to come up with a nuanced rule that indicates when a gerrymander may be in play — something the Supreme Court refused to do. That rule relies on the preservation of two values central to fair elections: that every minority voice should have an opportunity to be heard, and that the majority should rule.
A gerrymander can make it impossible for a minority party to achieve the majority, even if it receives the most votes in an election. Conversely, distorted maps may completely exclude a particular group of people from ever receiving an appropriate amount of representation. While these scenarios may sound the same, they’re two different dynamics that require different means of correction.
“Trying to apply the diagnostic for a violation of majority rule to a scenario where we’ve excluded people, or vice versa, is going to lead to trouble,” Magleby said.
Academics often debate the efficacy of particular tools — which has proven counterproductive.
In short, there’s no single means to determine whether a map has been manipulated in such a way to create harm. However, tools already exist to determine whether a map violates the principle of majority rule or is drawn to keep a particular group of people from having a voice in the system, the researchers said.
“Gerrymandering will be a threat until we come to the realization that we have to identify the values we want to preserve and then lean on social scientists to construct diagnostics that will tell you when you have and haven’t satisfied those values,” McDonald said. “We think it’s within reach.”
DALLAS, May 1, 2025 – After a seven-year battle, Santa Cruz today became the first California city to implement a sugary drink tax since 2018, when the beverage industry pressured the state legislature to pass a preemption bill blocking cities from enacting local excise taxes in a backroom deal to protect the industry’s profits.
Santa Cruz also becomes the first U.S. city to implement a sugary drink tax in seven years, representing a major victory for public health advocates against a soda industry that works nationwide to undermine public policies that reduce consumption of sugary drinks.
“Santa Cruz demonstrates that when presented with the facts about the dangers of sugary drinks, voters see through the soda industry’s multi-million-dollar efforts to deceive them with misinformation,” said Nancy Brown, CEO of the American Heart Association. “The American Heart Association was proud to support the ballot measure and remains committed to the city of Santa Cruz in this years-long David vs. Goliath effort against the beverage industry. By ensuring the voices of voters are heard in Santa Cruz and other communities nationwide, we can continue to pave the way for a healthier future and reduce the harmful effects of sugary drink overconsumption.”
The city of Santa Cruz was considering an initiative to implement a sugary drink tax when the 2018 preemption bill was passed and signed by then-Gov. Jerry Brown. As a result, Santa Cruz officials were forced to pull the initiative from the ballot. Advocates from Fresno and an elected official from Santa Cruz filed a lawsuit against the preemption law. In 2021, the Sacramento County Superior Court found the law’s penalty provisions unconstitutional, a ruling affirmed by an appeals court in 2023.
The Santa Cruz City Council then voted unanimously to place a sugary drink tax on the November 2024 ballot. The people of Santa Cruz voted in favor of Measure Z, which imposes a two-cents-per-ounce tax on soda and other sugary beverages that will generate an estimated $1.3 million per year for the city. A local advisory board will recommend how to invest the revenue.
Scientific studies have long shown that sugary drink consumption can lead to heart disease, type 2 diabetes and serious tooth decay. Children who regularly consume sugary drinks may be at higher risk of chronic disease. Taxes on sugary drinks, including soda, sports drinks and fruit drinks with added sugar, have proven effective at reducing purchases of these drinks. In addition, cities that have implemented sugary drink taxes have generated tens of millions of dollars in revenue for health-related community improvements, from funding pre-K programs to expanding healthy food access to improving parks and recreation centers.
“For decades, the American Heart Association has been on the forefront of the fight against the soda industry’s efforts to drive consumption of sugary drinks and increase profits,” Nancy Brown said. “At every turn, the soda industry has worked to defeat these proposals, putting profits ahead of public health. When communities are presented with the facts and given the opportunity to take action to address the health threats of sugary drinks, they are increasingly rejecting the soda industry’s deceptions.”
The Association remains steadfastly committed to the shared goal of decreasing sugary beverage consumption through sugary drink taxes and other policies including improving the nutrition of restaurant kids’ meals. The Association has worked with public health partners across the country to increase sugary beverage taxes in Boulder, Philadelphia, Seattle and several communities in California – including Santa Cruz. In 2018, the Association successfully advocated for healthier kids’ meals in restaurants (SB 1192), requiring restaurants offering children’s meals to include water or milk as the default beverage.
“The Association always has and always will support public policies that reduce sugary drink consumption so everyone, everywhere can live their longest, healthiest life,” Nancy Brown said.
###
About the American Heart Association The American Heart Association is a relentless force for a world of longer, healthier lives. Dedicated to ensuring equitable health in all communities, the organization has been a leading source of health information for more than one hundred years. Supported by more than 35 million volunteers globally, we fund groundbreaking research, advocate for the public’s health and provide critical resources to save and improve lives affected by cardiovascular disease and stroke. By driving breakthroughs and implementing proven solutions in science, policy and care, we work tirelessly to advance health and transform lives every day. Connect with us on heart.org, Facebook, X or by calling 1-800-AHA-USA1.
