Earth

In American history, we learn that the arrival of Spanish explorers led by Hernando de Soto in the 1500s was a watershed moment resulting in the collapse of Indigenous tribes and traditions across the southeastern United States.

While these expeditions unquestionably resulted in the deaths of countless Indigenous people and the relocation of remaining tribes, new research from Washington University in St. Louis provides evidence that Indigenous people in Oconee Valley -- present-day central Georgia -- continued to live and actively resist European influence for nearly 150 years.

The findings, published July 15 in American Antiquity, speak to the resistance and resilience of Indigenous people in the face of European insurgence, said Jacob Lulewicz, a lecturer in archaeology in Arts & Sciences and lead author.

"The case study presented in our paper reframes the historical contexts of early colonial encounters in the Oconee Valley by way of highlighting the longevity and endurance of Indigenous Mississippian traditions and rewriting narratives of interactions between Spanish colonizers and Native Americans," Lulewicz said.

It also draws into question the motives behind early explanations and interpretations that Euro-Americans proposed about Indigenous earthen mounds -- platforms built out of soil, clay and stone that were used for important ceremonies and rituals.

'Myths were purposively racist'

"By the mid-1700s, less than 100 years after the abandonment of the Dyar mound [now submerged under Lake Oconee], explanations for the non-Indigenous origins of earthen mounds were being espoused. As less than 100 years would have passed between the Indigenous use of mounds and these explanations, it could be argued that the motives for these myths were purposively racist, denying what would have been a recent collective memory of Indigenous use in favor of explanations that stole, and disenfranchised, these histories from contemporary Indigenous peoples," Lulewicz said.

The Dyar mound was excavated by University of Georgia archaeologists in the 1970s to make way for a dam. Lulewicz and co-authors -- Victor D. Thompson, professor of archaeology and director of the Laboratory of Archaeology at the University of Georgia; James Wettstaed, archaeologist at Chattahoochee-Oconee National Forests; and Mark Williams, director emeritus of the Laboratory of Archaeology at the University of Georgia -- received funding from the USDA Forest Service to re-date the platform mound, which contained classic markers of Indigenous rituals and ceremonies.

Using advanced radiocarbon dating techniques and complex statistical models, modern-day archaeologists are able to effectively construct high-resolution, high-precision chronologies. In many cases, they can determine, within a 10- to 20-year range, dates of things that happened as far back as 1,000 years ago.

"Radiocarbon dating is really important, not just for getting a date to see when things happened, but for understanding the tempo of how things changed throughout time and really understanding the complex histories of people over hundreds of years," Lulewicz said. "In archaeology, it's really easy to group things in long periods of time, but it would be false to say that nothing changed over those 500 years."

Their research yielded 20 new dates from up and down the mound, which provided a refined perspective on the effects that early Indigenous-colonizer encounters did, and did not, have on the Indigenous people and their traditions.

Missing from the mound was any sign of European artifacts, which is one of the reasons why archaeologists originally believed sites in the region were abruptly abandoned just after their first encounters with Spanish colonizers. "Not only did the ancestors of Muscogee (Creek) people continue their traditions atop the Dyar mound for nearly 150 years after these encounters, but they also actively rejected European things," Lulewicz said.

According to Lulewicz, the Dyar mound does not represent an isolated hold-over after contact with European colonizers. There are several examples of platform mounds that were used beyond the 16th century, including the Fatherland site associated with the Natchez in Louisiana, Cofitachequi in South Carolina and a range of towns throughout the Lower Mississippi Valley.

"However, the mound at Dyar represents one of the only confirmed examples, via absolute dating, of continued Mississippian traditions related to mound-use and construction to date."

Today, members of the Muscogee (Creek) Nation, descendants of the Mississippians who built platform mounds like the one at Dyar, live in Oklahoma. "We have a great, collaborative relationship with archaeologists of the Muscogee (Creek) Nation Historic and Cultural Preservation Department, so we sent them the paper to review. It was really well received. They saw, reflected in that paper, a lot of the traditions they still practice in Oklahoma and were generous enough to contribute commentary that bolstered the results presented in the paper," he said.

"This is where the archaeology that we write becomes so important in the present. ... Without this type of work, we are contributing to the disenfranchisement of Indigenous peoples from their history."

"Of course, they already knew many of the things we 'discovered,' but it was still meaningful to be able to reaffirm their ancestral link to the land."

In the end, Lulewicz said this is the most important part of the paper. "We are writing about real human lives -- Indigenous lives that we have historically treated very poorly and who continue to be treated poorly today in some cases. With the use of advanced radiocarbon dating and the development of really high resolution chronologies, we are able to more effectively reinject lives into narratives of the past."

Patients with gastrointestinal disorders - such as irritable bowel syndrome (IBS) and constipation - have greater symptom relief and improved wellbeing when treated at multidisciplinary clinics, new research shows.

Researchers from the University of Melbourne and St Vincent's Hospital have conducted a trial involving 144 patients to compare the effectiveness of a multidisciplinary clinic - involving gastroenterologists, dieticians, psychiatrists and physiotherapists - with usual gastroenterology specialist-only care.

These patients have poorly controlled symptoms such as bloating, pain and constipation and receive little relief from regular over-the-counter IBS medications.

Published in the Lancet Gastroenterology and Hepatology, researchers found 84 per cent (82 of 98) of patients in the multidisciplinary care group achieved global symptom improvement. They reported moderate or substantial improvement in IBS symptoms such as stool frequency, pain and bloating. This compared with 57 per cent (26 of 46) of patients in the standard care group.

Those in the multidisciplinary group also expressed greater improvement in psychological wellbeing, with a 40 per cent decrease in depression, compared with a nine per cent decrease for those in standard care.

Although the average cost per patient was significantly higher in the multidisciplinary-care group, researchers found patients benefited from treatment more, indicating that the overall long-term hospital cost would be less under this model.

Patients in the multidisciplinary group were also less likely to see their general practitioner for gut symptoms and were less likely to undergo tests outside of hospital during follow-up, suggesting broad cost savings.

Researchers found patients in the multidisciplinary clinic were less likely to take time off from work (26 per cent compared to 37 per cent of patients in standard care), further demonstrating the value of a more holistic treatment approach.

Researchers say the findings suggest that integrated multidisciplinary care for patients with a functional gastrointestinal disorder provides superior symptom relief and general wellbeing, and is more cost-effective, than traditional care.

University of Melbourne researcher and gastroenterologist at St Vincent's Hospital Dr Chamara Basnayake said more than half of the patients within the trial had attempted dietary therapy previously, and 60 per cent were classified as anxious, highlighting further need for an integrated approach to treatment.

"Functional gastrointestinal disorders are highly prevalent in the community with some patients experiencing extreme discomfort and illness for prolonged periods of time," Dr Basnayake said.

"Our research shows the importance of bringing together and integrating specialists into one clinic to enable immediate frontline care and improve quality of life for patients."

Researchers say further studies evaluating the longer-term outcomes of multidisciplinary treatment is needed.

"Despite the high prevalence and health system burden, very few studies have ever evaluated the different models of care for patients with gastrointestinal disorders," Dr Basnayake said.

Plant geneticists seeking to understand the history of the plants we eat can decode the genomes of ancient crops from rare, well-preserved samples. However, this approach leaves significant gaps in the timelines of where and when many modern-day fruits, vegetables, and cereal crops evolved, and paints an incomplete picture of what they looked like. A Science & Society article publishing July 14th in the journal Trends in Plant Science details a unique approach to filling these gaps using art--and calls on museum goers and art aficionados to help find paintings that could have useful depictions.

"It's a bit of an out-of-control hobby for me," says co-author Ive De Smet (@IveDeSmet1978), a plant biologist at the VIB-UGent Center for Plant Systems Biology in Belgium. "We may have some of the genetic code for certain ancient plants, but often not well-preserved samples, so looking at art can help put these species on a time map and track down their evolution."

The project stemmed from the lifelong friendship between De Smet and his colleague David Vergauwen, an art history lecturer at Amarant in Belgium. "I'm a biologist by training, and he's an art historian by training so we come from two totally different worlds," says De Smet. "During a trip a couple of years ago, we were standing in front of a painting and there was a piece of fruit that we didn't immediately recognize. He asked me what I thought it was and I said I didn't really know, and that maybe it was a bad painter. But he told me this was actually one of the best painters from the 17th century. So, if that's how the fruit was depicted, that's how it should look."

Upon investigating the use of art as a way to learn more about how plants evolved, De Smet found there could be something to it. For example, when scientists studied ancient Egyptian depictions of watermelons, they observed the familiar light and dark green stripes we see today. This, in combination with DNA extracted from a watermelon leaf found preserved in an Egyptian tomb, indicates the fruit was domesticated more than 4000 years ago and is not a modern invention.

Although paintings can give researchers clues about what fruits and vegetables looked like and where they were found in the past, the approach comes with challenges. A knowledge of art history is necessary--the quality and style of the artist impacts how realistic the plants depicted are. Even some renowned painters are not reliable sources. "For example, if you were interested in determining how a certain fruit or vegetable looked, and you used Picasso as a reference, you might get the wrong impression of its appearance," says Vergauwen.

The researchers are also limited by the accessibility of the art itself. Lesser-known or private collections can get overlooked, misleading researchers about timelines and geographic origins. Additionally, when plants are depicted in a painting, they are often not mentioned in its title. This means that the researchers must study each painting individually. "Woodland strawberries are very often depicted at the feet of the Virgin Mary. This will never be mentioned," De Smet says. "You really have to go to each and every one of these paintings and look at the feet to see if there's a small depiction of a woodland strawberry."

Thus, De Smet and Vergauwen hope to broaden their scope and tap into the scientific potential of art across the globe. "Ultimately, the conclusions we draw rely on the quality of the database we have," De Smet says. To help grow this database of art, they're asking people from around the world to provide pictures of paintings they encounter that depict plant-based food. "For us, it's easy to go to European collections like the Louvre in Paris, but there are also museums in Asia, or in Central and South America that could teach us a lot," he adds.

This approach has already shown that many common variations of fruits and vegetables far predate the field of modern genetics. "The things that we currently see in our supermarkets and our fruit and vegetable shops are not necessarily things achieved by tweaking with molecular biology," says De Smet. "Very often this is natural variation that already existed centuries, or even thousands of years ago, that has now become fashionable again."

Addressing potential threats from predators has not slowed the dramatic decline of mountain caribou in British Columbia and Alberta, according to a new study by scientists from the University of Alberta and two other western Canadian universities.

Biologists reassessed data from research published in the Proceedings of the National Academy of Sciences (PNAS) in 2019. The original research has been cited as showing that killing wolves and fencing pregnant caribou are solutions to saving the endangered animals.

The scientists looked closely at the data provided in the 2019 study, and found that when routine statistical tests were included, predator control lacked statistical support. They found that some of the steepest declines in caribou populations were in southern British Columbia, areas where wolves are not major caribou predators.

"No matter how you calculate it, the statistics don't back up culling wolves or fencing in caribou," said Viktoria Wagner, assistant professor in University of Alberta's Department of Biological Sciences and co-author.

Instead, the authors found that statistically caribou declines tracked closely with specific mountain caribou ecotypes. The deep-snow mountain caribou found from Wells Gray Park into the Kootenays experienced the steepest declines despite having a low number of caribou killed by wolves.

"This means something is going on that's killing off an endangered species and it isn't being addressed by predator management," said Toby Spribille, assistant professor in the Department of Biological Sciences and co-author on the study. He noted that although focusing on predator threats is simple and easy to communicate, it does not capture the interactions that are causing mountain caribou to go extinct. For instance, the loss of habitat to logging, snowpack variation and snowmobiling are factors that need to be addressed, the authors say.

"This is an uncomfortable conversation to have but it should not be left out of scientific models," noted Spribille."If decision-makers are going to be serious about species conservation, it's really critical that they get all the information."

"Forests provide caribou with refuge from wolves and separation from other prey animals, including elk, moose, and deer," said Lee Harding, retired Canadian Wildlife Service biologist and lead author on the study. "Without them, caribou must constantly be on the move to find food, exposing them on all sides. Predators are just one of the hazards."

Chris Darimont, professor at University of Victoria, Mathieu Bourbonnais, assistant professor at University of British Columbia Okanagan, and Andrew Cook, PhD student in UAlberta's Department of Biological Sciences, collaborated on this research.

The known timeline of the Aboriginal occupation of South Australia's Riverland region has been vastly extended by new research led by Flinders University in collaboration with the River Murray and Mallee Aboriginal Corporation (RMMAC).

Radiocarbon dating of shell middens - remnants of meals eaten long ago - capture a record of Aboriginal occupation that extends to around 29,000 years, confirming the location as one of the oldest sites along the 2500km river to become the oldest River Murray Indigenous site in South Australia.

In the first comprehensive survey of the region, one of the oldest Indigenous sites along Australia's longest river system has been discovered. The results, published in Australian Archaeology, used radiocarbon dating methods to analyse river mussel shells from a midden site overlooking the Pike River floodplain downstream of Renmark.

"These results include the first pre-Last Glacial Maximum ages returned on the River Murray in South Australia and extend the known Aboriginal occupation of the Riverland by approximately 22,000 years," says Flinders University archaeologist and PhD candidate Craig Westell.

More than 30 additional radiocarbon dates were collected in the region, spanning the period from 15,000 years ago to the recent present. Together, the results relate Aboriginal people to an ever-changing river landscape, and provide deeper insights into how they responded to these challenges.

The period represented by the radiocarbon results brackets the Last Glacial Maximum (commonly known as the last Ice Age) when climatic conditions were colder and drier and when the arid zone extended over much of the Murray-Darling Basin. The river and lake systems of the basin were under stress during this time.

In the Riverland, dunes were advancing into the Murray floodplains, river flows were unpredictable, and salt was accumulating in the valley.

The ecological impacts witnessed during one of the worst droughts on record, the so-called Millennium Drought (from late 1996 extending to mid-2010), provides an idea of the challenges Aboriginal people may have faced along the river during the Last Glacial Maximum, and other periods of climate stress, researchers conclude.

"These studies show how our ancestors have lived over many thousands of years in the Riverland region and how they managed to survive during times of hardship and plenty," says RMMAC spokesperson Fiona Giles.

"This new research, published in Australian Archaeology, fills in a significant geographic gap in our understanding of the Aboriginal occupation chronologies for the Murray-Darling Basin," adds co-author Associate Professor Amy Roberts.

The dating, which was undertaken at the Australian Nuclear Science and Technology Organisation (ANSTO) and Waikato University, forms part of a much larger and ongoing research program led by Associate Professor Amy Roberts which is undertaking a broad-ranging investigation of past and contemporary Aboriginal connections to the Riverland region.

The paper, 'Initial results and observations on a radiocarbon dating program in the Riverland region of South Australia' (2020) by C Westell, A Roberts, M Morrison, G Jacobsen and the River Murray and Mallee Aboriginal Corporation has been published in Australian Archaeology DOI: 10.1080/03122417.2020.1787928

The Last Glacial Maximum is the most significant climatic event to face modern humans since their arrival in Australia some 40,000-50,000 years ago. Recent studies have demonstrated that the LGM in Australia was a period of significant cooling and increased aridity beginning ?30 ka and peaking between ?23 and 18 ka.

Consumption of DHA supplements, an omega-3 fatty acid, by breastfeeding mothers is ineffective in preventing bronchopulmonary dysplasia in preterm infants born before the 29th week of pregnancy. This is the main conclusion of a Canada-wide study published today in the Journal of the American Medical Association (JAMA).

"Bronchopulmonary dysplasia is a chronic inflammatory lung disease that affects half of preterm infants, causing significant breathing difficulties that can make them become dependent on ventilators and oxygen for months," explained the study's lead author, Dr. Isabelle Marc, pediatrician, professor at the Université Laval Faculty of Medicine and researcher at the CHU de Québec-Université Laval Research Centre. "Babies with bronchopulmonary dysplasia are at greater risk for neurodevelopmental disabilities, respiratory issues, and, in rare cases, death."

The study was conducted with the help of 461 women who had recently given birth before their 29th week of pregnancy. The participants, all of whom were breastfeeding their child, were randomly divided into two groups: one group taking a daily supplement containing 1.2 g of DHA and the other taking a placebo pill.

"By the time they reached 36 weeks of development, we found no improvement in the respiratory condition of preemies whose mother had taken DHA supplements," said Dr. Marc. "Having mothers take DHA supplements during the newborn period to prevent bronchopulmonary dysplasia in their very preterm infants cannot be recommended at this point," added the study's last author, Dr. Pascal Lavoie, who is a researcher at BC Children's Hospital, a neonatologist at BC Women's Hospital + Health Centre and an associate professor at the University of British Columbia Faculty of Medicine. "It would be preferable for mothers to get these omega-3s by eating a balanced diet containing fish and other foods rich in omega-3s," concluded Dr. Marc.

The researchers will continue monitoring the children until they are 18 months old in order to determine whether omega-3s have positive effects on brain development in very preterm infants.

LA JOLLA--(July 14, 2020) People wrongfully accused of a crime often wait years--if ever--to be exonerated. Many of these wrongfully accused cases stem from unreliable eyewitness testimony. Now, Salk scientists have identified a new way of presenting a lineup to an eyewitness that could improve the likelihood that the correct suspect is identified and reduce the number of innocent people sentenced to jail. Their report is published in Nature Communications on July 14, 2020.

"Misidentification by eyewitnesses is a long-standing problem in our society. Our new lineup method uncovers the structure of eyewitness memory, removes decision bias from the identification process, and quantifies performance of individual witnesses," says Salk Professor Thomas D. Albright, co-corresponding author of the study. "This study is a great example of using laboratory science to bring about criminal justice reform."

In the United States, nearly 70 percent of DNA exonerations are due to misidentifications by eyewitnesses, according to the Innocence Project. To overcome this societal problem, research has focused on factors that influence the likelihood that a witness will identify the correct person. One key factor is the way individuals are presented to the eyewitness during the lineup, according to Albright, who co-chaired a National Academy of Sciences committee to examine the validity of eyewitness identification. Albright, an expert in the fields of visual perception and recognition, taps into decades of research suggesting that people commonly misperceive visual events, and memories of those events are continuously augmented and deteriorate over time.

Currently, the two most common (or traditional) methods used by law enforcement are known as simultaneous and sequential lineups. In the simultaneous method the eyewitness views six photographs of individuals at the same time; in the sequential method the eyewitness views six photos, one at a time. The witness then either identifies a suspect or rejects the lineup if no face matches their memory of the crime scene.

The research team sought to create a new lineup method that would help estimate the strengths of memories for each face and eliminate unconscious biases that shape decisions without awareness.

"Traditional lineups just reveal the top choice--the tip of the iceberg. But the cause of the witness's decision is ambiguous. It may reflect strong memory for the culprit, or it may mean that the witness was not very discerning," says Albright. "Our new procedure overcomes that ambiguity by revealing the strength of recognition memory for all lineup faces."

The scientists used a technique, called the method of paired comparisons, which works similar to how an optometrist gives an eye exam: Just like looking through pairs of lenses and stating which lens is clearer, the eyewitness is shown two photographs of individuals at a time and they choose the one that looks more similar to the person they remember from the crime scene. The procedure yields an estimate of the strength of recognition memory for each lineup face. Statistical analysis of these memory strengths then reveals the probability of correctly identifying the culprit.

"Our methods derive from a branch of science called sensory psychophysics," says Staff Scientist Sergei Gepshtein, first and co-corresponding author of the paper, who founded and directs the Collaboratory for Adaptive Sensory Technologies at Salk. "Psychophysical tools are designed to reveal how properties of the physical world are ordered--or 'scaled'--in the mind. Our approach allowed us to peek into the 'black box' and measure how lineup faces are organized in the witness's memory in terms of their similarity to the culprit."

The paired comparison method yields greater information about the identity of the culprit than previous methods. What is more, it offers an unprecedented quantitative index of certainty for individual eyewitnesses, which is what the judge and jury really need to know.

"The conduct of a lineup is just one application of our method," says Gepshtein. "Another application is selection of lineup 'fillers,' which are faces of people known to be innocent. The fillers should not be too similar or too dissimilar to the suspect. Because the new method reveals the perceived similarity of faces, it can be used to optimize the choice of lineup fillers."

The paired comparison lineup holds much promise as a research tool as well as a practical tool for investigation and prosecution of crimes. The authors hope that the new technique will soon be applied in real police casework, leading to more correct identifications and fewer wrongful convictions.

"Convictions should be based on science, not precedent," says Albright.

New research led by The University of Queensland has provided the first comprehensive analysis of pesticide mixtures in creeks and rivers discharging to the Great Barrier Reef.

UQ's School of Earth and Environmental Sciences researcher Associate Professor Michael Warne conducted the study with the Queensland Department of Environment and Science, and analysed 2600 water samples from 15 waterways that discharge into the Great Barrier Reef lagoon over a four-year period.

"While I knew many water samples would contain mixtures, I was shocked to find that essentially every sample contained mixtures of pesticides," Dr Warne said.

"We found 99.8 per cent of the samples contained pesticide mixtures with up to 20 pesticides in any single water sample.

"The issue with having mixtures of pesticides is that as the number of pesticides increases the impact to aquatic ecosystems generally increases.

"This work strongly supports the inclusion of the pesticide reduction target in the Reef 2050 Water Quality Improvement Plan which aims to protect at least 99 per cent of aquatic organisms at the mouths of rivers from the adverse effects of all pesticides."

Dr Warne said the best way to address the problem of pesticides and pesticide mixtures in run-off was to work with land managers, share information and help them to improve their pesticide management practices.

"We are doing just that with other partners including Farmacist, James Cook University and the Department of Environment and Science through Project Bluewater which is funded by the Great Barrier Reef Foundation," he said.

"This project is working with 70 sugar cane farmers in the Barratta Creek and Plane River catchments to improve their pesticide management and application, upgrade equipment, reduce pesticide use and switch to using lower risk pesticides.

"We have found the farmers involved to be very eager to engage with the science - they have embraced the challenge and are making significant steps toward improvement.

"We are looking to expand this project to include considerably more farmers in more catchments and make more rapid progress in reducing pesticide losses to waterways.

"There is always hope, but this study reveals the pesticide situation is more complex than we previously realised."

TAMPA, Fla. -- Chronic lymphocytic leukemia (CLL) is the most common leukemia in adults. One in four new leukemia cases are CLL. Early-stage CLL patients often do not require therapy, but for those with aggressive disease or who have failed previous treatments, a targeted therapy approach may be necessary. One such targeted therapy is PI3K inhibitors, which are drugs that block a specific protein that controls cell growth. While this type of treatment has proved beneficial for patients, it often comes with serious side effects, such as low blood count, liver damage, lung inflammation or intestinal issues. Moffitt Cancer Center researchers want to learn more about how this type of inhibitor works with the body's immune system to determine if there are ways to predict or mitigate associated adverse effects. Their findings were published in the July 14 issue of Blood Advances, a journal of the American Society of Hematology.

Phosphatidylinositol 3-kinase (PI3K) is one of the most important signaling pathways regulating cell growth, migration and survival. When activated, the PI3K pathway contributes to tumor growth and resistance to therapy. It is why this pathway has become a target for several new cancer drugs, including ones to treat CLL.

For this study, Moffitt investigators used mouse models to evaluate three PI3K inhibitors: two that are Food and Drug Administration approved -- idelalisib and duvelisib -- and one investigational drug, umbralisib.

"Toxicities for this class of PI3K inhibitors are thought to be immune-mediated, but we know little about what is going on within the immune system to cause these reactions," said Eva Sahakian, Ph.D., study author and research scientist in Moffitt's Immunology Program. "Our study sought to answer that question, looking specifically at how these drugs suppressed regulatory T cells and other immune cells."

Regulatory T cells (Tregs) are a small subset of cells that are actively involved in suppressing anti-tumor immune response through the targeting of other immune cells. They are thought to play a significant role in the progression of cancer and are generally increased in CLL patients.

The research team found that while all three PI3K inhibitors were effective in the treatment of CLL, idelalisib and duvelisib led to increased immune-mediated toxicities, as well as impaired function and a reduced number of Tregs. However, Treg volume and function were well maintained with umbralisib. The researchers believe this is because in addition to inhibiting PI3K, umbralisib is a dual inhibitor that also targets CK1ε, a protein essential to regulating cell division and tumor growth.

"Our findings show the immune-mediated adverse reactions seen in CLL patients following PI3K inhibitor therapy can be counteracted with the addition of CK1ε inhibition. The dual PI3K/ CK1ε inhibitor umbralisib offers an improved safety profile for CLL patients," says Javier Pinilla-Ibarz, M.D., Ph.D., study author, senior member and head of the Lymphoma Section of the Malignant Hematology Department at Moffitt.

The researchers suggest dual PI3K/CK1ε inhibitor therapy could possibly be used in the treatment of other types of cancer. They would also like to investigate CK1ε inhibitor therapy by itself and in combination with other therapies once an investigational drug becomes available.

New research has demonstrated that kidneys can be revived prior to transplantation by delivering a cell therapy directly to the organ.

A team led by Newcastle University researcher, Dr Emily Thompson, is the first to discover that a new technique called Normothermic Machine Perfusion - when combined with stem cells - can be used to improve the function of 'marginal' kidneys, organs that are at risk of not working as well.

By treating kidneys with a type of stem cell called MultiStem the organs demonstrated a number of responses associated with better function caused by the release of anti-inflammatory molecules, improving blood flow to damaged cells and increasing urine production.

The research is published in the American Journal of Transplantation and Dr Thompson, from the Translational and Clinical Research institute, Newcastle University, UK and transplant surgery registrar at Newcastle Hospitals NHS Foundation Trust, led the research project. She is funded by Kidney Research UK and by the NIHR Blood and Transplant Research Unit in Organ Donation and Transplantation.

"By improving the quality of donor kidneys and increasing the number available, we hope to be able to reduce the waiting time and improve the health outcomes for patients," said Dr Thompson.

Shortage of kidneys to transplant

Kidney transplantation is the best treatment for patients with kidney failure, however, on average, patients wait three years for an organ to become available.

Many kidneys offered for donation are classified as marginal and this can often lead to post-transplant problems, increasing the chances of a patient requiring a second organ.

Dr Thompson said: "It was exciting to see the results of the research as it could offer a new way to make more kidneys suitable for transplant. It could offer hope to more people on dialysis and shorten the waiting list.

"This work has completely changed our thinking as it shows that we may be able to pre-treat the kidney directly, instead of treating the whole patient before or after transplantation. This opens up exciting opportunities to explore other therapies, such as gene therapy or other stem cells, and we are moving our research forward and looking at a lot of other drugs and therapies.

"Currently these tests are done in the lab but if they transfer to the patient setting, as we hope they will, those who receive a transplant may receive better quality kidneys that last a lifetime."

"This exciting research shows that stem cell treatment could improve the quality of donor kidneys," said Dr Maria Tennant, Head of Communications at Kidney Research UK.

"Right now, there are not enough kidney transplants available for everyone who needs one, and a transplant doesn't last for life. We hope this treatment ultimately means more kidneys become fit for transplant and are able to last much longer."

Reviving organs

Normothermic Machine Perfusion, a recently-established method for organ preservation - optimises metabolism primarily for storage and transportation and pumps oxygenated blood through the organ at body temperature, keeping the kidney working after it has been removed from the donor. This research focussed on whether the technique can also be used to deliver treatments to improve kidney function.

The benefit of this technique is that treatments can be delivered directly to the kidney. It is performed while the kidney is outside of the body so there are fewer concerns about side effects in a patient.

In the research, Dr Thompson treated kidneys with an adult stem cell product candidate called MultiStem™ which is being developed by Athersys,Inc. based in Cleveland, Ohio. The treated kidneys showed a number of responses associated with better function caused by the release of anti-inflammatory molecules (cytokines and growth factors specifically reduction of IL-1beta, an increase in IL-10 and IDO activity) which improved blood flow to damaged cells leading to increased urine production.

Dr Thompson has already been recognised for this work receiving the Medawar medal from the British Transplantation Society and the Da Vinci award from the European Society of Transplantation.

The next step is to find out if the improvements seen on the machine result in better transplants. Dr Thompson will be progressing the work with further research and testing and it is hoped this innovation will progress to human clinical trials within a few years.

Recent NASA missions to asteroids have gathered important data about the early evolution of our Solar System, planet formation, and how life may have originated on Earth. These missions also provide crucial information to deflect asteroids that could hit Earth.

Missions like the OSIRIS-REx mission to Asteroid Bennu and the Hyabusa II mission to Ryugu, are often conducted by robotic explorers that send images back to Earth showing complex asteroid surfaces with cracked, perched boulders and rubble fields.

In order to better understand the behavior of asteroid material and design successful robotic explorers, researchers must first understand exactly how these explorers impact the surface of asteroids during their touchdown.

In a paper published in the journal Icarus, researchers in the University of Rochester's Department of Physics and Astronomy, including Alice Quillen, a professor of physics and astronomy, and Esteban Wright, a graduate student in Quillen's lab, conducted lab experiments to determine what happens when explorers and other objects touch down on complex, granular surfaces in low gravity environments. Their research provides important information in improving the accuracy of data collection on asteroids.

"Controlling the robotic explorer is paramount to mission success," Wright says. "We want to avoid a situation where the lander is stuck in its own landing site or potentially bounces off the surface and goes in an unintended direction. It may also be desirable for the explorer to skip across the surface to travel long distances."

The researchers used sand to represent an asteroid's surface in the lab. They used marbles to measure how objects impact the sandy surfaces at different angles, and filmed the marbles with high-speed video in order to track the marbles' trajectories and spin during impact with the sand.

"Granular materials like sand are usually quite absorbent upon impact," Quillen says. "Similar to a cannonball ricocheting off of water, pushed sand can act like a snow in front of a snowplow, lifting the projectile, causing it to skip off the surface."

The researchers constructed a mathematical model that includes the Froude number, a dimensionless ratio that depends on gravity, speed, and size. By scaling the model with the Froude number, the researchers were able to apply the knowledge gained from their experiments with the marbles to low gravity environments, such as those found on the surfaces of asteroids.

"We found that at velocities near the escape velocity--the velocity at which an object will escape gravitational attraction--many if not most rocks and boulders are likely to ricochet on asteroids," Wright says.

The results provide an explanation for why asteroids have strewn boulders and rocks that are perched on their surfaces, and they also influence the angle at which robotic missions will need to successfully touch down on the surface of an asteroid.

"Robotic missions that touch down on the surface of an asteroid will need to control the moment of touch down so that they don't bounce," Quillen says. "The robots can accomplish this by making their angle of impact nearly vertical, by reducing the velocity of impact to a very small value, or by making the velocity of impact large enough to form a deep crater that the robotic explorer won't bounce out of."

In November 2019, clinicians, health administrators, educators and researchers from around the world gathered in Toronto to discuss how to best address social determinants of health from a primary care perspective. Participants developed starting points for accessible and feasible actions to improve health equity in their own primary care setting. They emphasized strategies to incorporate community members, especially those with lived experiences of discrimination, in the health care design team. Additionally, they highlighted the need to address structural determinants of health, including racism, capitalism and colonialism.

Researchers affiliated with the Robert Graham Center for Policy Studies in Family Medicine and Primary Care conducted a descriptive bibliometric analysis to determine the gender ratio of scholarly authorship on publications by its researchers between 2008 and 2018. While the average gender ratio of RGC researchers across this period was 46.3 percent female to 56.4 percent male, gender disparities in authorship were much starker. For example, roughly two-thirds of 229 publications listed a male first author, and almost all had at least one male author. While the RGC team recognizes the limitations of a single-case study, their intention is to broaden the discussion about gender parity in authorship among academic medical researchers.

NASA's Aqua satellite used infrared light to identify the strongest storms and coldest cloud top temperatures in Tropical Depression 6E. Aqua found a few small areas of strength but cooler sea surface temperatures are expected to weaken them.

Tropical Depression 6E formed in the Eastern Pacific Ocean by 5 p.m. EDT on July 13 and was located well to the southwest of Baja California Sur, Mexico.

On July 14 at 5:50 a.m. EDT (0950 UTC), the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA's Aqua satellite analyzed Tropical Depression 6E's cloud tops in infrared light. Infrared data provides temperature information, and the strongest thunderstorms that reach high into the atmosphere have the coldest cloud top temperatures.

Aqua found the most powerful thunderstorms in several small, fragmented areas northeast, southeast and southwest of the center of circulation, where temperatures were as cold as or colder than minus 70 degrees Fahrenheit (minus 56.6 Celsius). Cloud top temperatures that cold indicate strong storms with the potential to generate heavy rainfall. Cloud top temperatures around the rest of the depression were warmer, indicating less-powerful storms.

At 11 a.m. EDT (1500 UTC) on July 14, the NHC said the center of Tropical Depression Six-E was located near latitude 18.1 degrees north and longitude 116.6 degrees west. 6E is far from land areas and is about 545 miles (880 km) southwest of the southern tip of Baja California, Mexico. The depression is moving toward the west-northwest near 16 mph (26 kph). A faster motion toward the west-northwest or west is expected during the next day or two. The estimated minimum central pressure is 1008 millibars. Maximum sustained winds are near 30 mph (45 kph) with higher gusts. Little change in strength is forecast during the next day or two.

NHC forecaster Robbie Berg noted that, "The depression is forecast to reach waters colder than 26 degrees Celsius (78 degrees Fahrenheit) in 12 to 24 hours, which should extinguish the remaining deep convection." Tropical cyclones require sea surface temperatures of at least 26.6 degrees Celsius (80 degrees Fahrenheit) to maintain intensity. Therefore, the depression is expected to become a remnant low or dissipate by early Wednesday.

It might seem as though humans have little in common with the lowly yeast cell. Humans have hair, skin, muscles, and bones, among other attributes. Yeast have, well, none of those things.

But besides their obvious differences, yeast and humans, and much of life for that matter, have a great deal in common, especially at the cellular level. One of these commonalities is the enzyme our cells use to make RNA copies of sections of our DNA. The enzyme slides along a strand of DNA that has been unpacked from the chromosome in which it resides, to "read" the genetic code, and then assembles an RNA strand that contains the same code. This copying process, known as transcription, is what happens at a molecular level when a gene is activated in an organism. The enzyme responsible for it, RNA polymerase, is found in all eukaryotic cells (cells with a nucleus) and it is essentially the same in all of them, whether the cells are from a redwood, an earthworm, a caribou, or a mushroom.

That fact has presented a mystery for scientists, though: Although the DNA in a yeast cell is different in many ways from the DNA in a human cell, the same enzyme is able to work with both. Now, a team of Caltech researchers has discovered one way this happens.

In a paper appearing in the July 15 issue of Molecular Cell, the team, which includes Paul Sternberg, Bren Professor of Biology, and graduate student Porfirio Quintero Cadena, shows that the enzyme is biologically tailored to match different types of DNA through the addition of a tail of amino acids (amino acids being the building blocks of proteins and enzymes) whose length correlates with the length of the DNA the enzyme works with. The longer the DNA, the longer the amino acid tail.

"An interesting question has been how the wide, molecularly diverse range of species on Earth can all use the same mechanism of gene activation," says Quintero Cadena. "Specifically, because this mechanism requires that two parts of a DNA molecule come together, it should be more difficult for species with long DNA molecules to transcribe genes."

To envision how the amino acid tails help the enzymes work with two pieces of a long DNA molecule, it helps to imagine the tails and DNA like pieces of Velcro, with the enzyme consisting of two Velcro halves that each latch onto a complementary section of DNA. To begin transcribing the DNA into RNA, the two halves need to "find" each other and link up. This process of linking up is actually rather arbitrary. The two pieces of DNA move around randomly inside the cell until they happen to bump into each other.

Longer amino acid tails do not increase the chances of those random encounters, but they do make the enzymes more "sticky," so when they bump into each other, it is more likely that they will stay together.

That is not the only way the amino acid tails assist in the transcription of DNA, however. Quintero Cadena says by bringing more enzymes together, the tails may also sometimes create a membraneless organelle, essentially a zone within the cell where DNA transcription is localized. Generally, each organelle of a cell can be thought of as a discrete object that is surrounded by its own membrane--one that holds in its contents. However, the team's research shows that when it comes to polymerase, their tails help the enzymes to gather themselves into a locale without needing to be contained by a membrane. This is because the amino acid tails attached to the polymerase enzyme have a greater affinity for other amino acid tails than they do for the fluid that fills the cell. It is not unlike how oil that has been mixed into water will separate itself and gather into its own droplets.

However, Quintero Cadena adds, unlike oil, which has no affinity for water, the amino acid tails can be chemically tailored by the cell to have as much or as little affinity for other cellular contents as necessary. This allows the cell to adjust how strongly the enzymes gather around each other.

Quintero Cadena says these discoveries provide a clearer idea of how genes are activated in a cell, and how the same cellular machinery has adapted through evolution to function in very different organisms.

"In the short term, this subtly but importantly changes the cartoon in our heads of how molecules interact to turn on a gene," he says. "In the long term, a better understanding of gene activation paints a more complete picture of the inner workings of a cell, which may help us understand how things that go wrong in a cell can contribute to diseases, and more generally to understand how cells change over time to adapt in different environments."