The discovery, published in Nature, describes the skeletal remains of a young adult found in a cave in Borneo, who had part of the left lower leg and left foot amputated, probably as a child, at least 31,000 years ago. The person survived the surgical procedure, living for at least another six to nine years.

The find presents a remarkable feat. It is notoriously difficult to prevent infections in surgical amputations, even to this day. Yet 30,000 years ago a community was able to successfully navigate veins, arteries, nerves, and tissue, and keep the wound clean so that it healed successfully. The individual went on the live into adulthood where an unknown cause eventually led to their death.

Bioarchaeologist and an expert in ancient skeletons, Dr Melandri Vlok, at University of Sydney said the find is “incredibly exciting and unexpected.”

“The discovery implies that at least some modern human foraging groups in tropical Asia had developed sophisticated medical knowledge and skills long before the Neolithic farming transition,” said Dr Vlok, who is co-lead author of the paper and a postdoctoral research associate in Sydney Southeast Asia Centre.

Studying bones

The skeleton of the young adult, possibly in their 20s when they died, was carefully buried within LiangTebo cave — located Borneo in East Kalimantan, in a limestone karst area that harbours some of the world’s earliest dated rock art.

The bones were uncovered by archaeologists from Griffith University and University of Western Australia (UWA) just days before borders closed for the COVID-19 pandemic in March 2020. The team was led by Professor Maxime Aubert and Dr Tim Maloney (Griffith University), Dr India Dilkes-Hall (UWA) and Mr Andika Priyatno from the Kalimantan Timur Cultural Heritage Preservation Centre.

The University of Sydney’s Dr Vlok was invited to study the bones when they were brought back to Australia.

“No one told me they had not found the left foot in the grave,” Dr Vlok said. “They kept it hidden from me to see what I would find.”

As Dr Vlok laid the bones out, the left leg looked withered, and was the size of a child’s, but the individual was an adult. She unwrapped the part of the leg that contained the stump and noticed the cut was clean, well healed and had no evidence of any infection. “The chances the amputation was an accident was so infinitely small,” Dr Vlok said. “The only conclusion was this was stone age surgery.”

Dr Vlok ran to the office to tell her research colleagues what she had found. “I told them I thought it looked like a surgical amputation,” she said. “It wasn’t until then that they said they already knew the foot was missing.” Dr Vlok had just confirmed their suspicions. The foot was never placed in the grave to begin with.

An accident

While it is not entirely clear what led to the amputation, the individual also had a very well healed neck fracture and trauma to their collar bone that may have occurred during the same event, said Dr Vlok.

“An accident, such as a rock fall may have caused the injuries, and it was clearly recognised by the community that the foot had to be taken off for the child to survive,” she said.

“It is an extremely rugged environment with steep mountains dotted with caves containing some of the oldest paintings created by our species,” said Professor Aubert.

Archaeologists including excavation lead Dr Tim Maloney had to kayak into the valley and scale the enormous cliff to get into the cave, proving just how remarkable it was for someone with only one leg to have survived in such challenging terrain.

“This unique find challenges assumptions of humanity’s capabilities in the past and is set to significantly advance our understanding of human lifeways in tropical rainforests,” said Dr Dilkes-Hall.

Nature has evolved these structures to harness the sun’s energy through photosynthesis, but these sunlight receivers don’t belong to plants. They’re found in microbes known as cyanobacteria, the evolutionary descendants of the first organisms on Earth capable of taking sunlight, water and carbon dioxide and turning them into sugars and oxygen.

Published Aug. 31 in the journal Nature, the findings immediately shed new light on microbial photosynthesis — specifically, how light energy is captured and sent to where it’s needed to power the conversion of carbon dioxide into sugars. Going forward, the insights could also help researchers remediate harmful bacteria in the environment, develop artificial photosynthetic systems for renewable energy and enlist microbes in sustainable manufacturing that starts with the raw materials of carbon dioxide and sunlight.

“There’s a lot of interest in using cyanobacteria as solar-powered factories that capture sunlight and convert it into a kind of energy that can be used to make important products,” said Cheryl Kerfeld, Hannah Distinguished Professor of structural bioengineering in the College of Natural Science. “With a blueprint like the one we’ve provided in this study, you can start thinking about tuning and optimizing the light-harvesting component of photosynthesis.”

“Once you see how something works, you have a better idea of how you can modify it and manipulate it. That’s a big advantage,” said Markus Sutter, a senior research associate in the Kerfeld Lab, which operates at MSU and Berkeley Lab in California.

The cyanobacterial antenna structures, which are called phycobilisomes, are complex collections of pigments and proteins, which assemble into relatively massive complexes.

For decades, researchers have been working to visualize the different building blocks of phycobilisomes to try to understand how they’re put together. Phycobilisomes are fragile, necessitating this piecemeal approach. Historically, researchers have been unable to get the high-resolution images of intact antennae needed to understand how they capture and conduct light energy.

Now, thanks to an international team of experts and advances in a technique known as cryo-electron microscopy, the structure of a cyanobacterial light harvesting antenna is available with nearly atomic resolution. The team included researchers from MSU, Berkeley Lab, the University of California, Berkeley and the University of South Bohemia in the Czech Republic.

“We were fortunate to be a team made up of people with complementary expertise, people who worked well together,” said Kerfeld, who is also a member of the MSU-DOE Plant Research Laboratory, which is supported by the U.S. Department of Energy. “The group had the right chemistry.”

‘A long journey full of nice surprises’

“This work is a breakthrough in the field of photosynthesis,” said Paul Sauer, a postdoctoral researcher in Professor Eva Nogales’ cryogenic electron microscopy lab at Berkeley Lab and UC Berkeley.

“The complete light-harvesting structure of a cyanobacteria’s antenna has been missing until now,” Sauer said. “Our discovery helps us understand how evolution came up with ways to turn carbon dioxide and light into oxygen and sugar in bacteria, long before any plants existed on our planet.”

Along with Kerfeld, Sauer is a corresponding author of the new article. The team documented several notable results, including finding a new phycobilisome protein and observing two new ways that the phycobilisome orients its light-capturing rods that hadn’t been resolved before.

“It’s 12 pages of discoveries,” said María Agustina Domínguez-Martín of the Nature report. As a postdoctoral researcher in the Kerfeld Lab, Domínguez-Martín initiated the study at MSU and brought it to completion at the Berkeley Lab. She is currently at the University of Cordoba in Spain as part of the Marie Sk?owdoska-Curie Postdoctoral Fellowship. “It’s been a long journey full of nice surprises.”

One surprise, for example, came in how a relatively small protein can act as a surge protector for the massive antenna. Before this work, researchers knew the phycobilisome could corral molecules called orange carotenoid proteins, or OCPs, when the phycobilisome had absorbed too much sunlight. The OCPs release the excess energy as heat, protecting a cyanobacterium’s photosynthetic system from burning up.

Until now, there’s been debate about how many OCPs the phycobilisome could bind and where those binding sites were. The new research answers these fundamental questions and offers potentially practical insights.

This kind of surge-protecting system — which is called photoprotection and has analogs in the plant world — naturally tends to be wasteful. Cyanobacteria are slow to turn their photoprotection off after it has done its job. Now, with the complete picture of how the surge protector works, researchers can design ways to engineer “smart,” less wasteful photoprotection, Kerfeld said.

And, despite helping make the planet habitable for humans and countless other organisms that need oxygen to survive, cyanobacteria have a dark side. Cyanobacteria blooms in lakes, ponds and reservoirs can produce toxins that are deadly to native ecosystems as well as humans and their pets. Having a blueprint of how the bacteria not only collect the sun’s energy, but also protect themselves from too much of it could inspire new ideas to attack harmful blooms.

Beyond the new answers and potential applications this work offers, the researchers are also excited about the new questions it raises and the research it could inspire.

“If you think of this like Legos, you can keep building up, right? The proteins and pigments are like blocks making the phycobilisome, but then that’s part of the photosystem, which is in the cell membrane, which is part of the entire cell,” Sutter said. “We’re climbing up the ladder of scale in a way. We’ve found something new on our rung, but we can’t say we’ve got the system settled.”

“We’ve answered some questions, but we’ve opened the doors on others and, to me, that’s what makes it a breakthrough,” Domínguez-Martín said. “I’m excited to see how the field develops from here.”

This work was supported by the U.S. Department of Energy Office of Science, the National Institutes of Health, the Czech Science Foundation and the European Union’s Horizon 2020 research and innovation program.

A new study by neuroscientists at the University of California, Berkeley, simulated the effects of food insecurity in juvenile mice and found lasting changes later in life.

“We show that irregular access to food in the late juvenile and early adolescent period affects learning, decision-making and dopamine neurons in adulthood,” said Linda Wilbrecht, UC Berkeley professor of psychology and member of the Helen Wills Neuroscience Institute.

One key difference in behavior involved cognitive flexibility: the ability to generate new solutions when the world changes.

“Mice searching for rewards might be inflexible, sticking to only one strategy even when it no longer yields a reward, or they might be flexible and quickly try out new strategies. We found that the stability of the food supply mice had when they were young governed how flexible they were under different conditions when they were grown up,” she said.

Epidemiological studies have linked food insecurity in children and adolescents with weight gain in later life, as well as learning problems and lower scores in mathematics, reading and vocabulary. But these studies are confounded by other poverty-related issues, such as maternal depression and environmental stressors. The new study was designed to look at the developmental and behavioral impacts of food insecurity in a controlled setting not possible using human subjects.

The study has implications for humans. Policymakers acknowledge the importance of good nutrition in early childhood through high school, with federally-funded free or reduced-price breakfast and lunch programs available in schools throughout the United States. The federal Supplemental Nutrition Assistance Program (SNAP) also provides benefits to supplement the food budget of needy families. For families living paycheck to paycheck, these food programs have demonstrated effects — in particular, boosted performance in school and rates of graduation.

But there may be times when kids cannot access food programs, such as during summer vacation. Programs may also inadvertently create a feast and famine cycle when benefits are distributed with weeks between payments, potentially leaving impoverished families unable to afford food at the end of each payment cycle. According to a recent report from the U.S. Department of Agriculture, 6.2% of households with children — 2.3 million households total — were food insecure in 2021.

“I think that we have to understand that even transient food insecurity matters, the brain doesn’t just catch up later. Food insecurity can have long-term impacts on how someone’s brain functions,” Wilbrecht said. “The ability to learn and make decisions is something that’s developing during childhood and adolescence, and we are seeing how these critical skills are impacted by access to food. Access to food is something that we can address in this county. Feeding and benefits programs exist, and we can make them better by making access to benefits or food more reliable and consistent. Supporting brain development is a good reason to support food programs.”

The research, conducted with UC Berkeley faculty members Helen Bateup, Stephan Lammel and their lab colleagues, will appear in an upcoming print edition of the journal Current Biology. It was posted online July 20.

Flexibility under changing rules

Wilbrecht and her colleagues, including Robert Wood Johnson Foundation Health and Society Scholar Ezequiel Galarce, mimicked human food insecurity in mice by delivering food on an irregular schedule while still allowing enough food to maintain safe body weight. This food regimen began a week before puberty onset in mice, equivalent to late childhood in humans, and continued for 20 days through the equivalent of late teen ages in mice. Another group of mice was offered food whenever they wanted it.

They then tested cognition in adulthood using foraging tasks where mice searched a changing environment for rewards. For example, a behavior — in this case, learning which odor led to the Honey Nut Cheerios — might be successful for a short time, but not forever. A second odor now predicted where the reward was hidden.

The well-fed and food-insecure mice were tested as adults in both certain and uncertain settings, with noticeable differences in cognitive flexibility. Food-insecure mice were more flexible in uncertain situations than were well-fed mice, while well-fed mice were more flexible in more stable situations.

“You would have to test in the field to see how these different flexibility profiles affect survival,” she said. “The findings are nuanced, but hopeful, because we identify both gain and loss of function in learning and decision-making that are wrought by experience of scarcity.”

While the effect of food insecurity on cognition in male mice was robust, female mice showed no effect on cognition.

“This is one of the most robust behavioral effects we’ve ever seen when we’ve been modeling adversity,” Wilbrecht said.

Food insecurity had other decidedly negative effects in female mice, however. Those females who were food insecure when growing up tended to become overweight when given unrestricted food in adulthood, something mirrored in humans who’ve grown up with food insecurity. Male mice showed no such effect.

Doctoral student Wan Chen Lin and researchers in the Bateup and Lammel labs also looked at the brain’s reward network, which is governed by the neurotransmitter dopamine, and found changes there, as well, in male mice.

“We found that the neurons in the dopamine system, which is critical for learning, decision- making and reward-related behaviors, like addiction, were significantly altered in both their inputs and their outputs,” Wilbrecht said. “It suggests there are more broadscale changes in the learning and decision-making systems in the brain.”

For example, the researchers saw changes in the synapses of dopamine neurons that project to the nucleus accumbens and also found changes in dopamine release in the dorsal striatum. These dopamine neurons have been shown to play a role in learning and decision-making in numerous other studies.

The researchers are continuing their studies of food-insecure mice to determine if they are more susceptible as adults to addictive behaviors, which are associated with the dopamine network.

Other UC Berkeley authors of the paper are former postdoctoral fellow Polina Kosillo, former doctoral student Christine Liu and senior scientist Lung-Hao Tai. The work was supported the National Institutes of Health (R21 AA025172, U19NS113201) and the Robert Wood Johnson Foundation. Bateup is a Chan Zuckerberg Biohub investigator and a Weill Neurohub investigator.

Their findings are published in Cell Reports Physical Science.

While researchers have been exploring the possibility of converting carbon dioxide to ethylene for more than a decade, the UIC team’s approach is the first to achieve nearly 100% utilization of carbon dioxide to produce hydrocarbons. Their system uses electrolysis to transform captured carbon dioxide gas into high purity ethylene, with other carbon-based fuels and oxygen as byproducts.

The process can convert up to 6 metric tons of carbon dioxide into 1 metric ton of ethylene, recycling almost all carbon dioxide captured. Because the system runs on electricity, the use of renewable energy can make the process carbon negative.

According to Singh, his team’s approach surpasses the net-zero carbon goal of other carbon capture and conversion technologies by actually reducing the total carbon dioxide output from industry. “It’s a net negative,” he said. “For every 1 ton of ethylene produced, you’re taking 6 tons of CO₂ from point sources that otherwise would be released to the atmosphere.”

Previous attempts at converting carbon dioxide into ethylene have relied on reactors that produce ethylene within the source carbon dioxide emission stream. In these cases, as little as 10% of CO₂ emissions typically converts to ethylene. The ethylene must later be separated from the carbon dioxide in an energy-intensive process often involving fossil fuels.

In UIC’s approach, an electric current is passed through a cell, half of which is filled with captured carbon dioxide, the other half with a water-based solution. An electrified catalyst draws charged hydrogen atoms from the water molecules into the other half of the unit separated by a membrane, where they combine with charged carbon atoms from the carbon dioxide molecules to form ethylene.

Among manufactured chemicals worldwide, ethylene ranks third for carbon emissions after ammonia and cement. Ethylene is used not only to create plastic products for the packaging, agricultural and automotive industries, but also to produce chemicals used in antifreeze, medical sterilizers and vinyl siding for houses.

Ethylene is usually made in a process called steam cracking that requires enormous amounts of heat. Cracking generates about 1.5 metric tons of carbon emissions per ton of ethylene created. On average, manufacturers produce around 160 million tons of ethylene each year, which results in more than 260 million tons of carbon dioxide emissions worldwide.

In addition to ethylene, the UIC scientists were able to produce other carbon-rich products useful to industry with their electrolysis approach. They also achieved a very high solar energy conversion efficiency, converting 10% of energy from the solar panels directly to carbon product output. This is well above the state-of-the-art standard of 2%. For all the ethylene they produced, the solar energy conversion efficiency was around 4%, approximately the same rate as photosynthesis.

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To understand the history of the donkey’s domestication, teams at the Centre for Anthropobiology and Genomics of Toulouse (CNRS/ Université Toulouse 3 Paul Sabatier) and scientists¹ from 37 laboratories around the world worked together to build and analyse the most complete panel of genomes ever studied for this animal. It contains the genomes of 207 contemporary donkeys living on all continents, as well as those of 31 early donkeys and 15 wild equids. In an article published on 9 September in Science, the researchers reveal that the donkey was first domesticated in Africa in 5,000 B.C.E, around the time when the Sahara became the desert region we know today.

It was only 2,500 years later that donkeys left their place of origin in Africa and reached Europe and Asia, where this species developed lineages that, in some cases, still exist today.

By analysing archaeological remains, scientists also uncovered evidence of a previously unknown genetic lineage of donkeys that lived in the Levant 2,000 years ago. Furthermore, the influence of this lineage is thought to extend far beyond the region, and still today, fragments of its genetic heritage can be found throughout Europe. These discoveries call for new archaeological digs to find the initial source of domestication in Africa, as well as the sequencing of other early donkey genomes on both shores of the Mediterranean sea, to better understand the role of this animal in the history of trade between Europe and North Africa.

¹ The following French laboratories contributed to this study: Genoscope, François Jacob institute of biology (CNRS/CEA/Univ. D’Every-Val-d’Essonne), Archéorient laboratory (CNRS/Univ. Lumière Lyon 2), l’Institut de Paléontologie Humaine (CNRS/Museum d’histoire naturelle/Univ. De Perpignan via domitia), le laboratoire Archéologie des sociétés méditerranéennes (CNRS/Ministère de la culture/Univ. Paul Valery Montpellier). This work received support from the GeT-PlaGe and Genoscope platforms, members of the France Génomique infrastructure (BUCÉPHALE and MARENGO project), and numerous financial supports, in particular from ), the French National Research Agency (ANR-10-INBS 09), for funding from the CNRS (AnimalFarm IRP), and from the European Union, including from the European Research Council PEGASUS programme.

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The Hiroshima University research team published their findings in the journal Scientific Reports, a Nature publication, on August 17, 2022.

“While previous studies have demonstrated that chicken primordial germ cells possess a characteristic feature in sex determination, its mechanism remains unclear. To solve this challenge, we revealed gene expression profiles of male and female primordial germ cells derived from early chick embryos and then predicted the sex determination mechanism,” said Kennosuke Ichikawa, a postdoctoral researcher at the Genome Editing Innovation Center, Hiroshima University. This research is the first to predict the sex-determination mechanism by comparing the gene expression profiles of avian primordial germ cells at each embryonic stage, as well as by using a stimulation test.

Birds have unique mechanisms of sex determination, that are different from mammals. In mammals, which have an XX (female) — XY (male) sex chromosome system, their sex determination depends on the action of the Y-chromosome. In birds, which have a ZZ (male) — ZW (female) sex chromosome system, their sex depends on the action of the Z chromosome. Yet the molecular mechanism of sex determination remains unclear. The development of the reproductive glands called gonads, into either ovaries or testes, and the development of other sexual characteristics are at least partially cell autonomous. The researchers’ investigation of the sex-determination mechanism in birds provides them insight into the evolution of vertebrate sex-determining mechanisms.

To investigate the mechanisms underlying sex determination in avian germ cells, the team purified male and female primordial germ cells from the blood and the gonads, using fluorescence-activated cell sorting. With this process they achieved a purity of greater than 96 percent. They determined gene expression profiles of the primordial germ cells at each developmental stage for each sex using RNA-sequencing analysis, where next-generation sequencing is used to examine the quantity and sequences of RNA in a sample. Then, the researchers predicted the sex-determination mechanism of the primordial germ cells using bioinformatic analysis, where computer tools are used to understand biological data. To evaluate the prediction, they stimulated male primordial germ cells with retinoic acid in vitro, and examined the changes in gene expression.

Before settling in the gonads, the female circulating primordial germ cells obtained from blood displayed sex-biased expression. The primordial germ cells from the gonads also exhibited sex-biased expression, and the number of female-biased genes detected was higher than that of male-biased genes. The team realized that the female-biased genes in the primordial germ cells were enriched in some metabolic processes. To reveal the mechanisms underlying this process, the researchers performed stimulation tests.

The team used retinoic acid to stimulate the cultured primordial germ cells collected from male embryos. This stimulation resulted in the upregulation — the process where a cell’s components increase — of several female-biased genes. Overall, their results suggest that sex determination in avian primordial germ cells involves aspects of both cell-autonomous and somatic-cell regulation. Moreover, it appears that sex determination occurs earlier in females than in males.

“We successfully predicted female-specific potential processes and pathways in chicken primordial germ cells. We believe our data set can significantly contribute to elucidating the avian sex determination mechanism,” said Ichikawa.

Looking ahead to future work, the team plans to use the data set to identify the key molecules directly inducing the feminization of chicken primordial germ cells. “The ultimate goal of this study is to elucidate the sex determination mechanism and then establish a sex selection method in chickens using genome editing targeting the key molecules,” said Ichikawa.

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The team proposed a method to generate entangled photons at extreme-ultraviolet (XUV) wavelengths where no such source currently exists. Their work provides a road map on how to generate these entangled photons and use them to track the dynamics of electrons in molecules and materials on the incredibly short timescales of attoseconds.

“The entangled photons in our work are guaranteed to arrive at a given location within a very short duration of attoseconds, as long as they travel the same distance,” says Dr. Niranjan Shivaram, assistant professor of Physics and Astronomy. “This correlation in their arrival time makes them very useful to measure ultrafast events. One important application is in attosecond metrology to push the limits of measurement of the shortest time scale phenomena. This source of entangled photons can also be used in quantum imaging and spectroscopy, where entangled photons have been shown to enhance the ability to gain information, but now at XUV and even X-ray wavelengths.”

The authors of the publication, titled “Attosecond entangled photons from two-photon decay of metastable atoms: A source for attosecond experiments and beyond,” are all from the Purdue University Department of Physics and Astronomy and work with the Purdue Quantum Science and Engineering Institute (PQSEI). They are Dr. Yimeng Wang, recent graduate of Purdue University; Siddhant Pandey, PhD candidate in the field of experimental ultrafast spectroscopy; Dr. Chris H. Greene, Albert Overhauser Distinguished Professor of Physics and Astronomy; and Dr. Shivaram.

“The Department of Physics and Astronomy at Purdue has a strong atomic, molecular and optical (AMO) physics program, which brings together experts in various subfields of AMO,” says Shivaram. “Chris Greene’s expert knowledge of theoretical atomic physics combined with Niranjan’s background in the relatively young field of experimental attosecond science led to this collaborative project. While many Universities have AMO programs, Purdue’s AMO program is uniquely diverse in that it has experts in multiple subfields of AMO science.”

Each researcher played a significant role in this ongoing research. Greene initially suggested the idea of using photons emitted by helium atoms as a source of entangled photons and Shivaram suggested applications to attosecond science and proposed experimental schemes. Wang and Greene then developed the theoretical framework to calculate entangled photon emission from helium atoms, while Pandey and Shivaram made estimates of entangled photon emission/absorption rates and worked out the details of the proposed attosecond experimental schemes.

The publication marks the beginning of this research for Shivaram and Greene. In this publication, the authors propose the idea and work out the theoretical aspects of the experiment. Shivaram and Greene plan to continue to collaborate on experimental and further theoretical ideas. Shivaram’s lab, the Ultrafast Quantum Dynamics Group, is currently building an apparatus to experimentally demonstrate some of these ideas. According to Shivaram, the hope is that other researchers in attosecond science will begin working on these ideas. A concerted effort by many research groups could further increase the impact of this work. Eventually, they hope to get the timescale of entangled photons down to the zeptosecond, 10^-21 seconds.

“Typically, experiments on attosecond timescales are performed using attosecond laser pulses as ‘strobes’ to ‘image’ the electrons. Current limits on these pulses are around 40 attoseconds. Our proposed idea of using entangled photons could push this down to a few attoseconds or zeptoseconds,” says Shivaram.

In order to understand the timing, one must understand that electrons play a fundamental role in determining the behavior of atoms, molecules and solid materials. The timescale of motion of electrons is typically in the femtosecond (one millionth of a billionth of a second — 10^-15 seconds) and attosecond (one billionth of a billionth of a second, or 10^-18 seconds) scale. According to Shivaram, gaining insight into the dynamics of electrons and tracking their motion on these ultrashort timescales is essential.

“The goal of the field of ultrafast science is to make such ‘movies’ of electrons and then use light to control the behavior of these electrons to engineer chemical reactions, make materials with novel properties, make molecular-scale devices, etc.,” he says. “This is light-matter interaction at its most basic level, and the possibilities for discovery are many. A single zeptosecond is 10^-21 seconds. A thousand zeptoseconds is an attosecond. Researchers are only now beginning to explore zeptosecond phenomena, though it is experimentally out of reach due to lack of zeptosecond laser pulses. Our unique approach of using entangled photons instead of photons in laser pulses could allow us to reach the zeptosecond regime. This will require considerable experimental effort and is likely possible on the timescale of five years.”

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Human clinical trials of the drug, an antiparasitic compound known as AN15368, will hopefully begin in the next few years.

“I’m very optimistic,” said Rick Tarleton, corresponding author of the study and a UGA Athletic Association Distinguished Professor in the Franklin College of Arts and Sciences. “I think it has a really strong chance of being a real solution, not just a stand-in for something that works better than the drugs we currently have.”

The new drug works by targeting the parasite that causes the disease, Trypanosoma cruzi, also known as T. cruzi.

Nearly all people infected with the parasite experience flu-like symptoms such as fever, headaches and vomiting. However, after their immune response kicks in, their symptoms may subside.

But for 30% to 40% of patients, the infection can result in severe heart damage that can be both debilitating and life-threatening.

New drug is 100% effective in eliminating T. cruzi

Published in Nature Microbiology, the study found the new medication was 100% effective in curing mice, as well as non-human primates that were naturally infected by the parasite at a research facility in Texas. The animals also experienced no significant side effects from exposure to the drug.

Over the past several decades, previous treatment candidates went straight from experimental infections in mice to human clinical trials, where they failed to cure the infection. The new drug’s efficacy in non-human primates bodes well for how it will perform in humans.

“We’ve got something that is as close to effective as it can be in what is as close to a human as it could be, and there aren’t any side effects. That really de-risks it by a lot going into humans,” Tarleton said. “It doesn’t make it fail-safe, but it moves it much further along.”

Current medications to treat T. cruzi infection not ideal

T. cruzi is carried by blood-sucking insects known as kissing bugs. The insects can be found throughout North, Central and South America.

In addition to a nasty bite, the creatures carry the T. cruzi parasite, which is transmitted through their fecal matter. Victims can become infected when they unknowingly rub the insect’s feces into their eyes, nose or an open wound.

The infection may also be transmitted through organ transplants, from a pregnant person to their fetus or through contaminated food. However, infections from these pathways are less common.

The go-to medications used to treat Chagas aren’t terrible, Tarleton said, but they’re not ideal. They can pack some serious side effects and they’re not reliably effective, but they’re currently the only treatment option.

Patients also have to take the drugs for two months. And even the common but mild side effects like headache or nausea get old after a few weeks. As a result, about one in five people being treated for the disease stop taking their medications before they have a chance to cure the infection.

“Plus they have variable efficacy, and it’s not predictable,” Tarleton said. “I think most physicians in Latin America have to say, ‘We have a drug. It’s going to make you feel bad, and two months later after we finish it, we’re not really going to be able to tell you if it worked or not.’

“It’s really not a good inducement to take the medication.”

Chagas disease common in Latin American countries

Tens of millions of people across the Americas are infected with the parasite that causes Chagas disease. But it doesn’t get much media attention.

It’s most common in Latin American countries, particularly in low-income areas where housing isn’t ideal. Some of the countries with the highest rates of the disease include Bolivia, Venezuela, Argentina, Chile, Mexico and Brazil.

In homes with thatched roofs, mud walls or inadequate protection from the elements, kissing bugs thrive, making infection more likely.

Chagas disease poses significant risk to pets

The Centers for Disease Control and Prevention estimates around 300,000 people infected with the parasite currently live in the U.S. But because the condition isn’t a huge threat in places with good housing options, Chagas disease treatment and prevention doesn’t get much research funding.

There is growing concern about the T. cruzi infection rate among outdoor pets in the U.S., however. Working dogs and other pets that spend extended periods of time outside are contracting the parasite at an alarming rate.

“There are areas where the infection rates are 20% to 30% new infections per year,” Tarleton said. “Those tend to be severe infections where the dogs either die or develop a disease that makes them unable to work.”

Tarleton hopes to partner with veterinary pharmaceutical companies in the future to create a drug to treat the infection in pets as a means of funding diagnostics and medication purchases in Latin America.

For the present study, Tarleton partnered with colleagues at Anacor Pharmaceuticals, Texas A&M University, the University of Texas, the University of Kansas and Pfizer. Angel Padilla, Wei Wang, Dylan Orr, Brooke White, Arlene George and Huifeng Shen from UGA’s Center for Tropical and Emerging Global Diseases and the Department of Cellular Biology are co-authors on the paper.

Treatment of cancer is a long-term process because remnants of living cancer cells often evolve into aggressive forms and become untreatable. Hence, treatment plans often involve multiple drug combinations and/or radiation therapy in order to prevent cancer relapse. To combat the variety of cancer cell types, modern drugs have been developed to target specific biochemical processes that are unique within each cell type.

However, cancer cells are highly adaptive and able to develop mechanisms to avoid the effects of the treatment. “We want to prevent such adaptation by invading the main pillar of cellular life — how cells breathe — that means take up oxygen — and thus produce chemical energy for growth,” says David Ng, group leader at the MPI-P.

The research team produced a synthetic drug that travels into cells where it reacts to conditions found inside and triggers a chemical process. This allows the drug’s molecules to bind together and form tiny hairs that are a thousand times thinner than human hair. “These hairs are fluorescent, so you can look at them directly with a microscope as they form,” says Zhixuan Zhou, an Alexander-von-Humboldt-fellow and first author of the paper.

The scientists monitored the oxygen consumption in different cell types and found that the hairs stop all of them from converting oxygen into ATP, a molecule that is responsible for energy delivery in cells. The process worked even for those cells derived from untreatable metastatic cancer. As a result, the cells die rapidly within four hours. After some more years of research, the scientists hope that they can develop a new method to treat up-to-now untreatable cancer.

Weil, Ng and colleagues have shown an exciting outcome under controlled laboratory culture and will continue to unravel deeper insights on the basis of how these tiny hairs prevent the conversion of oxygen to chemical energy. With further development, these objects could in the future possibly also be manipulated to control other cellular processes to address other important diseases.

They have published their results in the Journal of the American Chemical Society.

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