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)
Saturday, September 20, 2025
Texas A&M researchers pioneer cryopreservation method to prevent organ cracking
The breakthrough approach may pave the way for successful, long-term organ transplants — bringing science fiction closer to medical reality.
Researchers at Texas A&M University are developing advanced cryopreservation techniques, aiming to preserve organs at subzero temperatures without cracking — a key step toward extending viability of biological samples.
Credit: Texas A&M University College of Engineering
Cryopreservation, or preserving biological tissue by cooling it to subzero temperatures, may bring to mind works of science fiction. Yet, researchers have been working on this technology for nearly 100 years. For most of the field’s history, minimal progress was made — until 2023, when researchers from the University of Minnesota successfully transplanted a cryopreserved kidney to another rat, showing the potential for cryopreserved organ transplants in humans.
However, cryopreserving larger organs presents a major challenge: the organs are more likely to crack due to the rapid cooling process. Preventing cracks is essential for human organ preservation and transplantation. Researchers from the J. Mike Walker ’66 Department of Mechanical Engineering at Texas A&M University, led by Dr. Matthew Powell-Palm, have published a paper outlining their discovery — a cryopreservation approach that may prevent cracking in organs.
To preserve organs outside the body for an extended period, researchers use vitrification, which involves freezing tissue in a solution and preserving it in a glassy state, allowing cells to be “frozen in time” without the risk of damage from ice crystals. By adjusting the makeup of a vitrification solution, researchers can study properties of the solution that affect an organ’s risk of cracking.
“In this study, we investigated different glass transition temperatures, which we believe play a dominant role in cracking,” said Powell-Palm, an assistant professor of mechanical engineering. “We learned that higher glass transition temperatures reduce the likelihood of cracking.”
Equipped with the knowledge that higher transition temperatures are less likely to cause cracks than lower temperatures, researchers can focus on creating aqueous vitrification solutions with higher glass transition temperatures to help avoid cracking.
“Cracking is only one part of the problem,” Powell-Palm said. “The solutions need to be biocompatible with the tissue as well.”
This knowledge is essential to the field of cryopreservation, which has applications beyond organ transplantation, including wildlife and biodiversity conservation, vaccine stabilization and food waste reduction. Cryopreservation can extend the viability of any biological sample, benefiting any life science field.
“This study offers a seminal contribution to our understanding of aqueous solution thermodynamics,” said co-author and Mechanical Engineering Department Head Dr. Guillermo Aguilar, who serves as the James and Ada Forsyth Professor. “I look forward to more encouraging results in this direction, which will ultimately yield an increased viability of biological systems of all scales—from single cells to whole organs.”
Powell-Palm and Aguilar’s co-authors on this paper include Dr. Soheil Kavian, Ph.D. students Crystal Alvarez and Ron Sellers, and undergraduate student Gabriel Arismendi Sanchez, all from the mechanical engineering department.
“At its core, mechanical engineering requires an understanding of how something — anything —works. This project integrates physical chemistry, glass physics, thermomechanics, and cryobiology,” said Powell-Palm. “These students have done an amazing job applying the holistic thinking that mechanical engineering requires to this work.”
This study was funded by the National Science Foundation’s Engineering Research Center for Advanced Technologies for the Preservation of Biological Systems, which funds the highest levels of cryopreservation research.
By Alyssa Schaechinger, Texas A&M University College of Engineering
A micrograph taken at 400x magnification shows the interior of an MG-63 bone cell. Small polystyrene microplastic spheres appear inside the cytoplasm and are highlighted in blue. The cell nucleus is shown in red
Credit: Mariana Cassani de Oliveira/LEMON/FCM-UNICAMP
The production and use of over 400 million tons of plastic each year has polluted beaches, rivers, and even the deepest parts of the ocean, reaching depths of up to 11,000 meters. In addition to visible environmental impacts, plastic contributes to climate change. It is estimated that plastic production generates 1.8 billion tons of greenhouse gases per year. Scientific evidence also suggests that using plastic materials in everyday life has impacted human health.
A large number of plastic particles detach from curtains, furniture, clothing, and other plastic objects. These particles remain suspended in the air, dissolve in drinking water, adhere to food, and can be inhaled, ingested, or come into contact with people’s skin. Consequently, scientists have found microplastics in blood, the brain, the placenta, breast milk, and human bones.
A study linked to a research project supported by FAPESP and published in the journal Osteoporosis International reviewed 62 scientific articles and found that microplastics have also been harming bone health in various ways. One notable example is their ability to impair the function of bone marrow stem cells by promoting the formation of osteoclasts, which are multinucleated cells that degrade tissue through a process known as bone resorption.
“The potential impact of microplastics on bones is the subject of scientific studies and isn’t negligible. For example, in vitro studies with bone tissue cells have shown that microplastics impair cell viability, accelerate cell aging, and alter cell differentiation, in addition to promoting inflammation,” says Rodrigo Bueno de Oliveira, coordinator of the Laboratory for Mineral and Bone Studies in Nephrology (LEMON) at the Faculty of Medical Sciences of the State University of Campinas (FCM-UNICAMP), in the state of São Paulo, Brazil.
Oliveira reports that studies on animals have found that accelerated osteoclast senescence can compromise bone microstructure, causing dysplasia. This can lead to bone weakening, deformities, and potentially pathological fractures. “In this study, the adverse effects observed culminated, worryingly, in the interruption of the animals’ skeletal growth,” says the researcher.
Oliveira further explains that, although the effects of these particles on bone mechanics are not yet fully understood, the data suggest that the presence of the material in the bloodstream, for example, may compromise bone health. “Most strikingly, a significant body of research suggests that microplastics can reach deep into bone tissue, such as bone marrow, and potentially cause disturbances in its metabolism,” he says.
Connection
Not surprisingly, Oliveira’s team is starting a research project to verify in practice what seems perfectly possible in theory: the relationship between exposure to microplastics and the worsening of metabolic bone diseases. Using animal models, the scientists will study the impact of microplastics on the strength of rodent femurs.
According to the International Osteoporosis Foundation (IOF), the prevalence of osteoporosis-related fractures is increasing worldwide due to the aging population. It is estimated that there will be a 32% increase in osteoporosis-related fractures by 2050.
“Improving quality of life and reducing the risk of bone complications, such as fractures, is a priority in healthcare. We already know that practices such as physical exercise, a balanced diet, and pharmacological treatments contribute significantly to this. However, although osteometabolic diseases are relatively well understood, there’s a gap in our knowledge regarding the influence of microplastics on the development of these diseases. Therefore, one of our goals is to generate evidence suggesting that microplastics could be a potential controllable environmental cause to explain, for example, the increase in the projected number of bone fractures,” says Oliveira.
About São Paulo Research Foundation (FAPESP) The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the State of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration. You can learn more about FAPESP at www.fapesp.br/en and visit FAPESP news agency at www.agencia.fapesp.br/en to keep updated with the latest scientific breakthroughs FAPESP helps achieve through its many programs, awards and research centers. You may also subscribe to FAPESP news agency at http://agencia.fapesp.br/subscribe.
Credit: Brian Stokes/University of Texas at Austin
Biologists at The University of Texas at Austin, who have reported discovering a bird that’s the natural result of a green jay and a blue jay’s mating, say it may be among the first examples of a hybrid animal that exists because of recent changing patterns in the climate. The two different parent species are separated by 7 million years of evolution, and their ranges didn’t overlap as recently as a few decades ago.
“We think it’s the first observed vertebrate that’s hybridized as a result of two species both expanding their ranges due, at least in part, to climate change,” said Brian Stokes, a graduate student in ecology, evolution and behavior at UT and first author of the study.
Stokes noted that past vertebrate hybrids have resulted from human activity, like the introduction of invasive species, or the recent expansion of one species’ range into another’s – think polar bears and grizzlies – but this case appears to have occurred when shifts in weather patterns spurred the expansion of both parent species.
In the 1950s, the ranges of green jays, a tropical bird found across Central America, extended just barely up from Mexico into south Texas and the range of blue jays, a temperate bird living all across the Eastern U.S., only extended about as far west as Houston. They almost never came into contact with each other. But since then, as green jays have pushed north and blue jays have pushed west, their ranges have converged around San Antonio.
As a Ph.D. candidate studying green jays in Texas, Stokes was in the habit of monitoring several social media sites where birders share photos of their sightings. It was one of several ways he located birds to trap, take blood samples for genetic analysis and release unharmed back to the wild. One day, he saw a grainy photo of an odd-looking blue bird with a black mask and white chest posted by a woman in a suburb northeast of San Antonio. It was vaguely like a blue jay, but clearly different. The backyard birder invited Stokes to her house to see it firsthand.
“The first day, we tried to catch it, but it was really uncooperative,” Stokes said. “But the second day, we got lucky.”
The bird got tangled in a mist net, basically a long rectangular mesh of black nylon threads stretched between two poles that is easy for a flying bird to overlook as it’s soaring through the air, focused on some destination beyond. Stokes caught and released dozens of other birds, before his quarry finally blundered into his net on the second day.
Stokes took a quick blood sample of this strange bird, banded its leg to help relocate it in the future, and then let it go. Interestingly, the bird disappeared for a few years and then returned to the woman’s yard in June 2025. It’s not clear what was so special about her yard.
“I don’t know what it was, but it was kind of like random happenstance,” he said. “If it had gone two houses down, probably it would have never been reported anywhere.”
According to an analysis by Stokes and his faculty advisor, integrative biology professor Tim Keitt, published in the journal Ecology and Evolution, the bird is a male hybrid offspring of a green jay mother and a blue jay father. That makes it like another hybrid that researchers in the 1970s brought into being by crossing a green jay and a blue jay in captivity. That taxidermically preserved bird looks much like the one Stokes and Keitt describe and is in the collections of the Fort Worth Museum of Science and History.
“Hybridization is probably way more common in the natural world than researchers know about because there’s just so much inability to report these things happening,” Stokes said. “And it’s probably possible in a lot of species that we just don’t see because they’re physically separated from one another and so they don’t get the chance to try to mate.”
The scientists’ work was supported by a ConTex Collaborative Research Grant through UT System, the Texas EcoLab Program and Planet Texas 2050, a University of Texas at Austin grand challenge initiative.
The researchers did not opt to name the hybrid bird, but other naturally occurring hybrids have received nicknames like “grolar bear” for the polar bear-grizzly hybrid, “coywolf” for a creature that’s part coyote and part wolf and “narluga” for an animal with both narwhal and beluga whale parents.
Green Jay and Blue Jay occurrences in Texas reported from 2000 to 2023 in eBird, a popular app for birders and citizen scientists to share their observations. Green points represent green jay occurrences, blue points denote blue jay occurrences and black points indicate localities of recorded co-occurrence.
Through a collaboration between U.S. and Kenyan researchers and Turkana communities of northern Kenya, scientists have uncovered key genetic adaptations underlying survival in hot and dry environments, revealing how natural selection has enabled this pastoralist population to thrive in a challenging landscape.
A new analysis of Turkana genomes through a collaboration between US and Kenyan institutions shows how the activity of key genes has changed over millennia to allow them to thrive in extreme desert conditions. The comprehensive study, published in Science, reveals how the Turkana people have evolved extraordinary physiological adaptations to survive in their harsh homeland, where water scarcity and extreme heat have shaped their lifestyle.
The Turkana Way of Life
The Turkana homeland stretches across a vast arid landscape in Northern Kenya where shade is rare and water even rarer. While their nomadic existence takes them around East Africa—into Uganda on the west, South Sudan on the northwest and Ethiopia on the north—this is one of the most arid regions of the world. Rainfall arrives in short, unpredictable bursts, and in this environment, securing enough water for themselves and their herds of goats and camels is a daily chore. The journey to fetch water can take several hours each day, often across terrain that is hot and devoid of vegetation.
The traditional pastoralist diet reflects both resourcefulness and adaptation to scarcity: for those adhering to a nomadic pastoralist lifestyle, it is estimated that 70–80% of their nutrition comes from animal sources, mostly milk, blood, and meat. This reliance is a common solution among pastoralist societies around the world, in environments where crops cannot grow and markets may be far away on foot.
Through years of documenting the Turkana community's lifestyle and studying blood and urine samples to assess their health, researchers found a striking paradox: "About 90% of the people we assessed were dehydrated but generally healthy." Ayroles said.
"The Turkana have maintained their traditional way of life for thousands of years, providing us with an extraordinary window into human adaptation," said the project co-PI, Prof. Julien Ayroles, a faculty member at the University of California, Berkeley.
Genomic Discoveries Through Community Partnership
After consultation with the communities' elders, area chiefs and local health officials, the team asked for permission to sample the communities' DNA. Working with the Turkana community, the researchers sequenced 367 whole genomes and analyzed over 7 million genetic variants to identify regions showing evidence of natural selection.
The genomic analysis found eight regions of DNA that had undergone natural selection, but one gene, STC1, stood out with exceptionally strong evidence of selection. STC1 is expressed in the kidneys and plays two vital roles that directly reflect the ecological challenges of both arid living and pastoralism. First, it helps the body conserve water by responding to antidiuretic hormone, allowing the Turkana to concentrate their urine and retain more water. Second, it may also play a role in protecting the kidneys from the waste generated by purine-rich foods like red meat. These waste products, such as urea and uric acid, must be filtered by the kidneys and in many people, too much dietary purine can lead to gout; a problem that appears to be rare among the Turkana.
Ancient Climate, Modern Genetics
Intriguingly, the timing of these genetic adaptations appears to coincide with the aridification of northern Africa, suggesting that as the climate became increasingly dry about 5,000 years ago, natural selection favored genetic variants that enhanced survival in desert conditions. This finding provides a compelling example of how human populations have evolved in direct response to major environmental changes. The genetic analyses show that these changes are also present in neighboring groups, including the Rendille, who live in this arid environment. "This research demonstrates how our ancestors successfully adapted to dramatic climate shifts through genetic evolution," noted Dr. Epem Esekon, the County Executive for Health and Sanitation in Turkana County, Kenya.
When Evolution Meets Urbanization
But the story doesn't end in the desert. As more Turkana migrate to towns and cities, a striking pattern emerges: the very genetic traits that aid survival could now carry hidden costs. This phenomenon, known as evolutionary mismatch, occurs when adaptations shaped by one environment become liabilities in another.
By comparing biomarkers and gene expression in the genomes of city-dwelling Turkana compared to their pastoral kin, the researchers found an imbalance of gene expression that may predispose them to chronic diseases, such as hypertension or obesity, which the researchers have also found to be more common in urban settings, where diets, water availability, and activity patterns are radically different.
“With more people shifting from rural to urban lifestyles, we are also seeing a change in disease patterns,” said the Acting Director General of the Kenya Medical Research Institute (KEMRI), Prof. Elijah Songok.
"Understanding these adaptations will guide health programs for the Turkana—especially as some shift from traditional pastoralism to city life," said Charles Miano, one of the study's coauthors and a graduate student at KEMRI in Nairobi.
The study has health implications for many traditional cultures in Africa and around the world that are having to adapt to rapidly changing environments or adopt urban lifestyles. Evolutionary mismatch likely leads to high rates of "lifestyle" diseases around the world, such as diabetes, coronary artery disease and high blood pressure.
"This study highlights how working with transitioning populations can lead to new models for understanding how present-day environments interact with past adaptations to potentially impact modern day disease risk," added Amanda Lea, co-PI of the ongoing study and an Assistant Professor at Vanderbilt University.
The Turkana Health and Genomics Project: A Partnership in Discovery
This story began not in a laboratory, but around desert campfires. Many of the questions this research addresses were generated during long meetings with the Turkana community, facilitated by the Turkana Health and Genomics Project (THGP), a long-term collaboration between Kenyan and U.S.-based researchers. From its earliest days, the project has centered on the co-production of knowledge, combining genomic science with traditional ecological and anthropological expertise. The research agenda emerged from dialogue with Turkana elders, scientists, and community members, conversations about health, diet, and change, often shared in the evening around a camp fire.
"Working with the Turkana has been transformative for this study," said Sospeter Ngoci Njeru, one of the THGP's leaders and deputy director of KEMRI's Centre for Community Driven Research. "Their insights into their environment, lifestyle and health have been essential to connecting our genetic findings to real-world biology and survival strategies."
Lessons for a Changing World and Giving Back
As the world faces rapid environmental change, the Turkana's story offers both inspiration and practical insights. For generations, this community has developed and maintained sophisticated strategies for surviving in a challenging and variable environment, knowledge that becomes increasingly valuable as climate change creates new survival challenges globally.
The research team is now creating a podcast in the native Turkana language that will not only share the study's findings in accessible ways but also will offer the community practical health considerations that arise with rapid lifestyle transitions, combining scientific insights with knowledge from within the community. Based on conversations with Turkana study communities, the study findings resonate with people’s perceptions about their capacity to go without water for long periods, but they also noted that other pastoralists in the region. like the Rendille, Samburu, Borana, Merille, Karimojong, and Toposa, are likely to share this adaptation due to living in similarly arid environments.
"I am deeply inspired by the fact that this work places the Turkana and sub-Saharan Africa at the forefront of genomic research, a field where indigenous populations have historically been underrepresented," Miano said.
“Worldwide, indigenous communities like the Turkana are essential partners in advancing our knowledge of human resilience,” said Dr. Dino Martins, Director of the Turkana Basin Institute. “Their experience provides lessons for how climate and environmental changes continue to shape human biology and health.”
The study appears online Sept. 18 in the journal Science.
Members of Kenya's Turkana community often walk miles each day in scorching heat to collect water for their animals and personal consumption.
