Tuesday, February 28, 2023

CU School of Medicine researchers part of national team that identified a new dietary approach to treatment for eosinophilic esophagitis

The research published in Lancet Gastroenterology and Hepatology shows that eliminating dairy alone is as effective as the six-food elimination diet that is standard for the condition.

Peer-Reviewed Publication

UNIVERSITY OF COLORADO ANSCHUTZ MEDICAL CAMPUS

Research by a team that includes two faculty members from the University of Colorado School of Medicine may change the treatment paradigm for patients with eosinophilic esophagitis (EoE), an allergic condition that causes chronic inflammation in the esophagus that can lead to esophageal narrowing and dysfunction.

Glenn Furuta, MD, professor of pediatric gastroenterology, hepatology, and nutrition, and Paul Menard-Katcher, MD, associate professor of gastroenterology, helped lead the National Institutes of Health (NIH)-funded, multisite study that shows that a single-food elimination diet — one in which dairy products are eliminated — is just as effective as the standard six-food elimination diet for achieving remission in eosinophilic esophagitis. The paper was published today in Lancet Gastroenterology and Hepatology.

“Eosinophilic esophagitis is a chronic disease that affects children and adults,” Furuta says. “It causes significant problems with eating dysfunction in young children, and in adults it causes problems with food getting stuck and food impactions, as well as problems with swallowing. EoE is classically thought of as an allergic disease sparked by food allergens, so there’s a lot of interest in trying to remove foods from the diet to treat it.”

The problem with that approach, Furuta says, is that there is no test to easily identify which food allergen causes EoE in any given patient. Gastroenterologists typically start treatment by removing the six most common food allergens — dairy, wheat, eggs, soy, fish/shellfish, and peanuts/tree nuts — then reintroducing them one by one to see which sparks the inflammation. It’s an approach that necessitates multiple endoscopies to pinpoint the precise cause of EoE, and one that presents a significant decrease in quality of life for patients who must severely limit their diet in addition to undergoing a series of invasive tests.

Looking for less-drastic options

Working with the Consortium of Eosinophilic Gastrointestinal eosinophiLic disease Researchers  (CEGIR) led jointly by the CU School of Medicine and Cincinnati Children’s Hospital Medical Center, Furuta and Menard-Katcher began looking for a less-drastic dietary treatment option for EoE. Knowing that dairy is the most common allergen responsible for the disease, they constructed a clinical trial for adults ages 18 to 60 with active EoE. Half of the participants were assigned the standard six-food elimination diet for six weeks, and half eliminated only dairy products over the same timeframe.

At the end of the almost three-year trial, the researchers discovered that histological remission was statistically the same in both groups. Thirty-four percent of participants had remission from eliminating dairy alone, indicating that method as an acceptable initial dietary therapy for EoE.

“We started off by saying, ‘Do we have to have so many foods eliminated? Is it necessary to go all the way to removing the six foods, or can we just start with the most common allergen first, and then if that’s not effective, move up to the six-food elimination diet?’” says Furuta, who is working with other CEGIR researchers on a similar study in pediatric EoE patients. “It was taking a very practical approach to addressing a very concerning problem.”

Alternative to medications

Other treatments for EOE include proton pump inhibitors, topical steroids, and expensive biologic medications, all of which come with side effects. Dietary therapy is preferred, Menard-Katcher says, but eliminating six foods can be intimidating, especially for children. Working with patient-advocacy groups as well as the NIH, the researchers strived to create a patient-friendly trial that would result in an easier path toward remission for more patients.

“We have a lot of patients who would love to do dietary therapy, if that enables them to avoid the use of chronic medications,” Menard-Katcher says. “But the six-food elimination diet has a lot of drawbacks. You’re talking about eliminating a lot of foods that people eat really commonly. Then you add to that the burden of repeated endoscopies to try and identify the trigger or triggers, knowing that you also might not identify those triggers. It’s much easier for a patient to hear that they might have to try eliminating dairy as a first-line therapy rather than dairy, wheat, eggs, soy, tree nuts, and seafood.”

Strength in gastrointestinal research

The new study not only is a boon for patients with EoE and the physicians who treat them; it’s also evidence of the strengths in research and treatment for EoE and similar gastrointestinal diseases on the CU Anschutz Medical Campus. That includes the Gastrointestinal Eosinophilic Diseases Program at Children’s Hospital Colorado, a multidisciplinary program that currently sees patients from around 40 states who travel to the clinic for research studies and multidisciplinary care.

“We feel very fortunate because just across campus, Dr. Menard-Katcher and his team are there on the adult side for us to transition our local patients to,” says Furuta, director of the Gastrointestinal Eosinophilic Diseases Program and section head of the Digestive Health Institute at Children’s Colorado. “Institutionally, on this campus, we have a fantastic team that is helping to shape the field.”

BU researchers receive $1.3m EPA grant to advance climate resilience among Mystic River communities


The three-year project aims to identify and address the cumulative impacts of chemical hazards and climate change that affect the 21 communities surrounding the Mystic River Watershed.

Grant and Award Announcement

BOSTON UNIVERSITY SCHOOL OF PUBLIC HEALTH

FOR IMMEDIATE RELEASE

February 28, 2023

Contact:

Jillian McKoy, jpmckoy@bu.edu

Michael Saunders, msaunder@bu.edu

##

BU Researchers Receive $1.3M EPA Grant to Advance Climate Resilience among Mystic River Communities

The three-year project aims to identify and address the cumulative impacts of chemical hazards and climate change that affect the 21 communities surrounding the Mystic River Watershed.

The 21 communities that surround Greater Boston’s Mystic River Watershed are exposed to many of the central threats of climate change, including urban heat islands and coastal and inland flooding, while also confronting multiple chemical exposures.

Now, with a new grant from the US Environmental Protection Agency (EPA), a team of Boston University School of Public Health (BUSPH) researchers are collaborating with the Greater Boston-based Mystic River Watershed Association (MyRWA) and other local community organizations to better understand how communities are affected by these chemical and climate stressors, and how they can become more resilient to the current and future impacts of climate change.

Dr. Jonathan Levy, chair and professor of environmental health at BUSPH, and Dr. Amruta Nori-Sarma, assistant professor of environmental health at BUSPH, will serve as co-principal investigators of the award, titled Advancing Community Resilience to Cumulative Climate Impacts in the Mystic River Watershed (ACRES). The grant totals $1.3 million over three years and is part of broader efforts by the EPA to support projects that advance environmental justice in underserved and overburdened communities across the country. A majority of MyRWA’s neighboring communities include residents who are low-income and people of color. The communities include Arlington, Belmont, Boston (Charlestown & East Boston), Burlington, Cambridge, Chelsea, Everett, Lexington, Malden, Medford, Melrose, Reading, Revere, Somerville, Stoneham, Wakefield, Watertown, Wilmington, Winchester, Winthrop, and Woburn.

The project is timely, as many cities are ramping up efforts to address the global climate crisis and protect their local communities against climate hazards.

The researchers will work closely with the Resilient Mystic Collaborative (RMC), a voluntary group among the Mystic River Watershed communities that builds regional climate resilience, to identify community concerns related to climate change and to develop candidate solutions that highlight health protection and equity alongside sustainability. They will connect this information with a geolocated database and mapping tool that will be used to identify places and populations at higher risk, allowing the RMC to prioritize climate-resilient policies and investments that can decrease and prevent chemical exposures and improve climate resilience among vulnerable populations over time.

“At the heart of the project, we are trying to understand how we can best protect vulnerable people and neighborhoods from chemical exposures given the growing effects of climate change,” says Dr. Levy. His team will support the MyRWA/RMC and other organizations actively engaged in this work with quantitative and qualitative analyses that will provide useful insight on how to best protect these high-risk communities.

“These communities are often also disproportionately burdened due to systemic issues such as historical redlining, which have important implications for development that stretch into present-day,” Dr. Nori-Sarma says. Climate change solutions may also lead to climate gentrification in urban communities where residents can no longer afford to live in their neighborhood due to the costs of green infrastructure and sustainability, she says. “The impact of exposure to all of these issues is likely to be greater than the sum of its parts.”

The researchers are eager to learn more about how to reduce the impact of multiple climate hazards on vulnerable residents.

“In addition to risks from flooding, storm surges, and heat islands, many communities also have a lot of industrial facilities as well as a lot of traffic and other sources of air pollution,” Dr. Levy says. “So we're trying to understand how to best address the cumulative burden that these communities are experiencing as they face different climate and chemical stressors simultaneously.”

“As we advance climate justice, it must be founded on community-engaged research,” says David Cash, EPA regional administrator for New England. “The work conducted under this grant will help target climate-related challenges facing the disadvantaged communities in the Mystic Watershed that have been overburdened by environmental pollution. This project will yield tangible benefits for people living in the Mystic Watershed and provide policy guidance for EPA nationwide.”

The team hopes the project will underscore the need for health equity to be centered in climate resilience planning, and provide a framework that can be applied in other communities across the US.

“Our project intends to meet these communities where they are, assess the challenges that they face and understand the interrelated nature of climate exposures and impacts on health, and provide communities with the tools that they need to advocate for themselves and their local environments,” says Dr. Nori-Sarma.

“As a student at BUSPH, I learned that community power can be built through research,” says MariangelĂ­ EchevarrĂ­a-Ramos, Climate Resilience Manager at MyRWA, a graduate of the school’s Master of Public Health program. “One of our community leaders often says, ‘No one knows everything, together we know a lot.’ What an exciting opportunity to blend top-notch academic research with on-the-ground lived experiences to help people stay safe from chemical exposures.”

**

About Boston University School of Public Health

Founded in 1976, Boston University School of Public Health is one of the top five ranked private schools of public health in the world. It offers master's- and doctoral-level education in public health. The faculty in six departments conduct policy-changing public health research around the world, with the mission of improving the health of populations—especially the disadvantaged, underserved, and vulnerable—locally and globally.

 

Artificial intelligence with a human touch

New project creates next-gen AI to improve diagnostics

Grant and Award Announcement

UNIVERSITY OF HOUSTON

Hien Van Nguyen, University of Houston associate professor of electrical and computer engineering 

IMAGE: HIEN VAN NGUYEN, UNIVERSITY OF HOUSTON ASSOCIATE PROFESSOR OF ELECTRICAL AND COMPUTER ENGINEERING, IS DEVELOPING NEXT-GEN ARTIFICIAL INTELLIGENCE TO IMPROVE MEDICAL DIAGNOSTICS. view more 

CREDIT: UNIVERSITY OF HOUSTON

Despite the remarkable progress in artificial intelligence (AI), several studies show that AI systems do not improve radiologists' diagnostic performance. In fact, diagnostic errors contribute to 40,000 - 80,000 deaths annually in U.S. hospitals. This lapse creates a pressing need: Build next-generation computer-aided diagnosis algorithms that are more interactive to fully realize the benefits of AI in improving medical diagnosis. 

That’s just what Hien Van Nguyen, University of Houston associate professor of electrical and computer engineering, is doing with a new $933,812 grant from the National Cancer Institute. He will focus on lung cancer diagnostics. 

“Current AI systems focus on improving stand-alone performances while neglecting team interaction with radiologists,” said Van Nguyen. “This project aims to develop a computational framework for AI to collaborate with human radiologists on medical diagnosis tasks.” 

That framework uses a unique combination of eye-gaze tracking, intention reverse engineering and reinforcement learning to decide when and how an AI system should interact with radiologists. 

To maximize time efficiency and minimize the amount of distraction on the clinical work, Van Nguyen is designing a user-friendly and minimally interfering interface for radiologist-AI interaction.  

The project evaluates the approaches on two clinically important applications: lung nodule detection and pulmonary embolism. Lung cancer is the second most common cancer, and pulmonary embolism is the third most common cause of cardiovascular death.  

“Studying how AI can help radiologists reduce these diseases' diagnostic errors will have significant clinical impacts,” said Van Nguyen. “This project will significantly advance the knowledge of the field by addressing important, but largely under-explored questions.”  

The questions include when and how AI systems should interact with radiologists and how to model radiologist visual scanning process. 

“Our approaches are creative and original because they represent a substantive departure from the existing algorithms. Instead of continuously providing AI predictions, our system uses a gaze-assisted reinforcement learning agent to determine the optimal time and type of information to present to radiologists,” said Van Nguyen.  

“Our project will advance the strategies for designing user interfaces for doctor-AI interaction by combining gaze-sensing and novel AI methodologies.”  

Blue whale foraging and reproduction are related to environmental conditions, study shows


Peer-Reviewed Publication

OREGON STATE UNIVERSITY

New Zealand blue whale 

IMAGE: A NEW ZEALAND BLUE WHALE SURFACES IN THE SOUTH TARANAKI BIGHT. view more 

CREDIT: DAWN BARLOW, MARINE MAMMAL INSTITUTE, OREGON STATE UNIVERSITY

NEWPORT, Ore. – A new study of New Zealand blue whales’ vocalizations indicates the whales are present year-round in the South Taranaki Bight and their behavior is influenced by environmental conditions in the region.

The findings are a significant advancement in researchers’ understanding of the habitat use and behavior of this population of blue whales, which Oregon State University researchers first identified as genetically distinct from other blue whale populations less than a decade ago.  

“We went from not knowing 10 years ago whether this was a distinct population to now understanding these whales’ ecology and their response to changing environmental conditions,” said the study’s lead author, Dawn Barlow, a postdoctoral scholar in OSU’s Marine Mammal Institute. “These findings can inform conservation management of this blue whale population and their habitat.”

The patterns and intensity of the whales’ calls and songs over two years showed strong seasonality in their foraging and breeding behavior, and the vocalizations changed based on environmental conditions such as a documented marine heatwave, Barlow said.

“During the marine heatwave, feeding-related calls were reduced, reflecting poor foraging conditions during that period,” Barlow said. “But we also saw changes in vocalizations in the next breeding period, an indication that they put less effort into reproduction following a period of poor feeding conditions.”

The study was just published in the journal Ecology and Evolution. Barlow conducted the research as a doctoral student in the Geospatial Ecology of Marine Megafauna Laboratory at Hatfield Marine Science Center in Newport, led by associate professor Leigh Torres, a co-author of the new paper.

Blue whales are the largest of all whales and are found in all oceans except the Arctic. Their populations were depleted due to commercial whaling in the early 1900s, and today they are listed as endangered under the International Union for Conservation of Nature’s Red List of Threatened Species.

The New Zealand whales’ habitat overlaps with a wide range of commercial activities, including oil and gas exploration and extraction, vessel traffic, fisheries, wind energy development and possible seabed mining.

Torres first hypothesized in 2013 that the South Taranaki Bight, between New Zealand’s North and South Islands, was an undocumented blue whale feeding ground. Following comprehensive data collection efforts, and using multiple lines of evidence, Torres, Barlow and colleagues were able to document in 2018 that the population in this region was genetically distinct from other blue whale populations.

Previous research was primarily based on observations researchers made during visits to the region in the summer months. But the researchers wanted to know more about the whales’ behavior during other parts of the year. They placed five hydrophones – a type of underwater microphone – that recorded continuously between January 2016 and February 2018, with only brief gaps to retrieve data every six months.

“Unlike many other baleen whales, this population stays in this region year-round,” Barlow said. “That means we can monitor what they are doing from one location. Listening is an effective way to do that.”

The hydrophone recordings showed that the whales’ “D” calls were strongly correlated with oceanographic conditions related to upwelling in the spring and summer. Upwelling is a process where deeper, cooler water is pushed toward the surface; the nutrient-rich water supports aggregations of krill that the blue whales feed on. The whales’ D calls were more intense during periods of strong upwelling.

The recordings also showed that the whales’ song vocalizations, which are produced by males and associated with breeding behavior, followed a highly seasonal pattern, with peak intensity in the fall. That timing aligns with past whaling records’ estimates of conception, Barlow said.

The hydrophone evidence of the breeding behavior and the whales’ presence in the region year-round can influence the animals’ national threat classification status, which impacts management practices, the researchers said.

Blue whales in New Zealand had been classified as migrant, but as a result of the research by Torres, Barlow and colleagues, the classification of has changed from migrant to data deficient. If the whales are reclassified as a resident population, that could impact management practices, but evidence of breeding in New Zealand is needed for that change to occur, the researchers said.

“Although no one has actually documented blue whales mating – it is hard to observe that directly – the increase in song during the expected time of mating is a strong indication of breeding in New Zealand waters,” Torres said. “Our study adds more evidence that these are resident New Zealand blue whales.”

Once the researchers were able to make the link between the whales’ behavior and their calls, they could then look at the calls and behavior relative to environmental patterns. Specifically, they noted how the whales’ foraging and breeding behavior changed during and after a 2016 marine heatwave.

During the marine heatwave, there were fewer aggregations of krill for the whales to feed on, which the researchers documented in a previous study. The reduction in foraging behavior correlated to less intense D calls during that period, and in the next breeding season, the breeding songs were also less intense.

The findings raise additional questions about how changing ocean conditions and human activity in the region are impacting the New Zealand blue whale population and reinforce the need for continued monitoring, the researchers said.

“We have come so far in 10 years in our knowledge of these blue whales - from not knowing this population existed to now understanding their year-round use of this region for feeding, mating and nursing,” Torres said. “New Zealanders should be excited and proud that their country is home to its own unique population of blue whales. We hope our work helps Kiwis manage and protect these whales.”

Additional coauthors are Holger Klinck, director of the Cornell University K. Lisa Yang Center for Conservation Bioacoustics, who also is affiliated with OSU’s Marine Mammal Institute; Dimitri Ponirakis of Cornell; and Trevor Branch of the University of Washington. The Marine Mammal Institute is part of Oregon State’s College of Agricultural Sciences.

AND VISA VERSA

Adult smokers with mental illness consume the most caffeine in the U.S.

Mood, metabolism and self-medication might explain use patterns among this population, according to Rutgers research

Peer-Reviewed Publication

RUTGERS UNIVERSITY

Americans are drinking more caffeinated beverages than ever before, but Rutgers researchers found one group that tops the charts in caffeine consumption: adult smokers with mental illness.

 

In a study published online ahead of print in the January issue of the journal Psychiatry ResearchJill M. Williams, director of the division of addiction psychiatry at Rutgers Robert Wood Johnson Medical School, found not only do adult smokers with bipolar disorder and schizophrenia drink the most caffeine, they are at the highest risk of negative health consequences.

 

“Caffeine is generally considered safe and even has some health benefits,” said Williams. “But we just don't understand the cognitive and psychiatric effects of high caffeine intake, especially among smokers with mental illness.”

 

Caffeine is one of the most widely used psychoactive drugs in the United States, with the main effects increased alertness, attention and vigilance. While it’s considered safe for most healthy adults to consume up to 400 milligrams of caffeine per day – the equivalent of about four cups of brewed coffee – consuming more than 600 milligrams isn’t recommended and can lead to anxiety, insomnia, excess stomach acid and heartburn.

 

Little is known about caffeine’s influence on executive functions, such as reasoning and decision making, and the studies that have been done have mostly included healthy adults without mental illness, Williams said. Even less is known about how high caffeine intake may impact psychiatric symptoms or sleep in adults with serious mental illness who smoke.

 

To address these gaps, Williams and colleagues from the Rutgers Department of Psychology and the University of California San Francisco School of Medicine analyzed data from 248 adult smokers recruited during a previous study. Participants were either outpatient smokers with schizophrenia or bipolar disorder or from a control group with no psychiatric diagnoses. All participants were pack-a-day smokers.

 

At the beginning of the study, participants completed surveys on smoking history, caffeine use, physical health and psychological symptoms. The researchers also collected blood samples to measure serum caffeine levels.

 

They found caffeine intake was highest among participants with bipolar disorder, followed by adults with schizophrenia. The control group consumed the least amount of caffeine.

 

Williams said there are several theories to explain the relationship between caffeine intake and mental illness. One is a well-established association between caffeine and smoking: People with mental illnesses smoke at rates two to three times higher than the general population, and because the tars in cigarette smoke increase the metabolism of caffeine, it takes more caffeine to achieve stimulating effects.

 

Another theory links high caffeine intake to adenosine receptors and supports a possible self-medication effect among people with mental illness, said Williams. People with mental illnesses also seem to have vulnerabilities to all types of addictive substances, putting them at higher risk for excess intake and more negative consequences. Additionally, the researchers found evidence that mood is linked to caffeine intake, especially bad mood.

 

Each of these explanations warrants further investigation, Williams said.

 

“Today, people consume huge amounts of caffeine in more concentrated forms – like energy drinks or double shots of espresso – far more than when our participants were surveyed,” she said. “And yet, the effects of high caffeine intake remain widely understudied. This is particularly true for people with mental illness.”

Better metric for prioritizing conservation of “evolutionarily distinctive” species

EDGE2 adds measures of scientific uncertainty and status of related species to existing metric

Peer-Reviewed Publication

PLOS

Better metric for prioritizing conservation of “evolutionarily distinctive” species 

IMAGE: THE PYGMY SLOTH (BRADYPUS PYGMAEUS) IS ENDEMIC TO THE ISLAND OF ESCUDO, PANAMA, AND IS BOTH EVOLUTIONARILY DISTINCT AND THREATENED WITH EXTINCTION. view more 

CREDIT: ZSL (CC-BY 4.0, HTTPS://CREATIVECOMMONS.ORG/LICENSES/BY/4.0/)

An updated metric for prioritizing species’ conservation that incorporates scientific uncertainty and complementarity between species, in addition to extinction risk and evolutionary distinctiveness, is publishing February 28th in the open access journal PLOS Biology, authored by Rikki Gumbs from the Zoological Society of London (ZSL), UK, and colleagues.

In 2007, ZSL established the Evolutionarily Distinct and Globally Endangered (EDGE) metric to prioritise species for conservation based on preserving evolutionary history embodied within endangered species. The approach allocates each species a score based on the evolutionary distance, measured in millions of years, that separates a species from its closest living relatives, and its conservation status in the IUCN Red List.

EDGE has since been applied to mammals, amphibians, birds, sharks and rays, corals, and flowering plants, and is used to allocate conservation funding. To update the EDGE metric to incorporate recent advances in evolutionary biology and conservation, ZSL hosted a workshop for conservation scientists and practitioners, who reached a consensus on EDGE2 – an updated metric that includes the extinction risk of closely related species and uncertainty in species’ relationships and conservation status.

Applying the EDGE2 methodology to 6,253 mammal species, the researchers found that the Mountain Pygmy Possum (Burramys parvus) scored highest, representing 25 million years of evolution at critical risk of extinction. They identified 645 priority species that together account for 81% of the evolutionary diversity at risk. Protecting the 100 highest ranking species from this list – representing 1.6% of all mammal species – would preserve over 700 million years of evolutionary history.

EDGE2 lists can help guide the effective and practical prioritization of limited conservation funds to preserve distinctive evolutionary features and ecological functions, the authors say. They also propose an EDGE2 research list, calling for further research on species that are evolutionarily distinct, but whose conservation status is unknown.

Gumbs adds, “The variety of life at which we marvel is the product of the shared and unique evolutionary histories of species past and present, yet many of the most evolutionarily distinct species on Earth today are at risk of extinction. We brought together experts in conservation science and practice to create a robust and coherent framework to prioritise the world’s most evolutionarily distinct species for conservation action, and applied the framework to produce an updated prioritisation of the world’s mammals.”

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In your coverage, please use this URL to provide access to the freely available paper in PLOS Biologyhttp://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3001991

Citation: Gumbs R, Gray CL, Böhm M, Burfield IJ, Couchman OR, Faith DP, et al. (2023) The EDGE2 protocol: Advancing the prioritisation of Evolutionarily Distinct and Globally Endangered species for practical conservation action. PLoS Biol 21(2): e3001991. https://doi.org/10.1371/journal.pbio.3001991

Author Countries: United Kingdom, United States of America, Australia, Canada, Germany, New Zealand

Funding: RG was funded by the Natural Environment Research Council Science and Solutions for a Changing Planet Doctoral Training Programme (grant number NE/L002515/1), the CASE component of which was funded by the Zoological Society of London - https://www.imperial.ac.uk/grantham/education/science-and-solutions-forachanging-planet-dtp/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.


The Red-bellied lemur (Eulemur rubriventer) is one of many threatened mammals now recognised as EDGE species following the improved approach to identifying robust priorities.

CREDIT

Rikki Gumbs (CC-BY 4.0, https://creativecommons.org/licenses/by/4.0/)

The Red Panda (Ailurus fulgens) is the only extant member of its family, Ailuridae, and is one of the highest priority EDGE mammals.

CREDIT

ZSL (CC-BY 4.0, https://creativecommons.org/licenses/by/4.0/)


JOURNAL

Parental investment may have aided evolution of larger brains

New study explores evolution of larger brains in context of energy-intensive needs during growth

Peer-Reviewed Publication

PLOS

A review of evidence from prior research provides new support for the possibility that the evolution of larger brains in some species was enabled through increased energy investment by parents in their offspring. Carel van Schaik of the Max Planck Institute for Animal Behavior in Konstanz, Germany, and colleagues present their arguments in a paper publishing February 28th in the open access journal PLOS Biology.

Between different species, larger relative brain size is associated with cognitive benefits that favor survival. However, larger brains come with higher energy costs. Prior research has examined these costs for adults in order to deepen understanding of evolutionary trends in brain size between different species. However, few studies have focused on the energy costs of the developing brain of young organisms.

To help fill that gap, van Schaik and colleagues addressed an apparent paradox: the larger a species’ brain, the more energy it requires during development—but large brains are not fully functional until well after they finish growing. This presents a “chicken-or-egg” or “bootstrapping” problem; most young offspring of larger-brained species should be unable to meet the energy demands of their own developing brains, raising the question of how larger brain size could have evolved.

The researchers hypothesize that warm-blooded species—which tend to have brains many times larger than cold-blooded species—evolved to have greater parental energy investment in their young, and this facilitated the evolution of larger brains.

To examine this possibility, the researchers reviewed evidence from prior studies on the evolution of parental energy investment in young offspring. Warm-blooded species invest energy in their young through such actions as producing eggs, lactating, providing food, carrying, or huddling to stay warm. Most cold-blooded species simply release eggs.

Detailed analyses showed that greater energy investment in young indeed evolved alongside the evolution of larger relative brain size, and that this greater investment also could have improved young offspring’s chances of survival.

These findings support the hypothesis that greater parental energy investment in young offspring facilitated the evolution of larger brains, and that the inability to provide that sustained energy in species that merely lay eggs, in turn, limited the evolution of larger brains. Future research could build on this study to shed further light on how larger brains evolved.

van Schaik adds, “The evolution of extended parental provisioning beyond the egg stage unblocked a major evolutionary constraint on brain size, and therefore unleashed a massive expansion of brain size and cognitive potential among warm-blooded birds and mammals. Almost all of them feed their young after birth or hatching and have much larger brains than their cold-blooded relatives.”

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In your coverage, please use this URL to provide access to the freely available paper in PLOS Biologyhttp://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3002016

Citation: van Schaik CP, Song Z, Schuppli C, Drobniak SM, Heldstab SA, Griesser M (2023) Extended parental provisioning and variation in vertebrate brain sizes. PLoS Biol 21(2): e3002016. https://doi.org/10.1371/journal.pbio.3002016

Author Countries: Switzerland, Germany, Poland

Funding: This work was supported by the DFG (German Research Foundation) Heisenberg Grant No. 4650/2-1 to MG. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Profiling abortions in low- and middle-income countries

Researchers found factors— including marriage, age and education— associated with pregnancy termination in 36 countries

Peer-Reviewed Publication

PLOS

Multiple factors including a women’s age, marriage status, education and how many living children she has, are associated with pregnancy termination in low- and middle-income countries, according to a new study published this week in the open-access journal PLOS Global Public Health by Djibril Ba of Penn State College of Medicine, US, and colleagues.

In low- and middle-income countries (LMICs), a woman’s decision to terminate a pregnancy is often impacted by a patriarchal structure of society, restrictive abortion laws, cultural and religious beliefs and economic factors. About 45% of all abortions are considered unsafe, or which 97% take place in LMICs. To reduce these unsafe abortions, it is crucial to fully understand the factors associated with the prevalence of pregnancy termination.

In the new study, the researchers used data on more than 1.2 million women aged 15-49 who participated in the Integrated Public Use Microdata Series (IPUMS) Demographic and Health Surveys (DHS). The women were from 36 LMICs across Africa and Asia and answered the question “Have you ever had a pregnancy terminated?” in addition to providing other health and sociodemographic data.

The average pooled weighted prevalence of pregnancy termination across the entire study was 13.3% (95% CI 13.2%-13.4%), ranging from a low of 7.8% in Namibia to 33.4% in Pakistan. Overall, being married had the strongest association with pregnancy termination (adjusted OR 2.94, 95%CI 2.84-3.05, p<0.001). However women with more than four children (adjusted OR 2.45, 95%CI 2.33-2.56, p<0.001), those over age 30, and those who had higher levels of education were also more likely to terminate pregnancies. Women currently breastfeeding and using contraceptives had lower odds of pregnancy termination. There was not a significant association between household wealth and odds of pregnancy termination.

Since the data only included women who self-reported pregnancy termination, they cannot be used to draw conclusions about the general populations of the LMICs studied. However, the authors conclude that the study provides some guidance for targeted public health interventions.

“Our current analysis suggests that policies that will effectively reduce the prevalence of pregnancy termination should target individuals such as married women [and] older women,” the researchers say. “Providing birth control assistance and promoting breastfeeding may also play an essential role in reducing the risk of unintended pregnancies and unsafe abortions in LMICs.”

The authors add: “There is a need for future demographic and health surveys (DHS) to distinguish between induced abortions, miscarriages, and stillbirths for every country. Such a distinction will guide pregnancy termination specific public health and medical intervention needs in Low-and Middle-Income Countries.”

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In your coverage please use this URL to provide access to the freely available article in PLOS Global Public Healthhttps://journals.plos.org/globalpublichealth/article?id=10.1371/journal.pgph.0001509        

Citation: Ba DM, Zhang Y, Pasha-Razzak O, Khunsriraksakul C, Maiga M, Chinchilli VM, et al. (2023) Factors associated with pregnancy termination in women of childbearing age in 36 low-and middle-income countries. PLOS Glob Public Health 3(2): e0001509. https://doi.org/10.1371/journal.pgph.0001509

Author Countries: USA

Funding: The authors received no specific funding for this work.