. Scientific Frontline

Thursday, March 21, 2024

World's first high-resolution brain developed by 3D printer

Franziska Chalupa-Gantner and Aleksandr Ovsianikov at work.
Photo Credit: Courtesy of Technische Universität Wien

In a joint project between TU Wien and MedUni Vienna, the world's first 3D-printed "brain phantom" has been developed, which is modelled on the structure of brain fibres and can be imaged using a special variant of magnetic resonance imaging (dMRI). As a scientific team led by TU Wien and MedUni Vienna has now shown in a study, these brain models can be used to advance research into neurodegenerative diseases such as Alzheimer's, Parkinson's and multiple sclerosis. The research work was published in the journal Advanced Materials Technologies.

Magnetic resonance imaging (MRI) is a widely used diagnostic imaging technique that is primarily used to examine the brain. MRI can be used to examine the structure and function of the brain without the use of ionizing radiation. In a special variant of MRI, diffusion-weighted MRI (dMRI), the direction of the nerve fibers in the brain can also be determined. However, it is very difficult to correctly determine the direction of nerve fibers at the crossing points of nerve fiber bundles, as nerve fibers with different directions overlap there. In order to further improve the process and test analysis and evaluation methods, an international team in collaboration with the TU Wien and the Medical University of Vienna developed a so-called "brain phantom", which was produced using a high-resolution 3D printing process.

Wednesday, March 20, 2024

Icy impacts: Planetary scientists use physics and images of impact craters to gauge the thickness of ice on Europa

Brandon Johnson and his team study impact craters around the solar system for clues about planetary bodies’ history and composition.
Photo Credit: Rebecca Robinos / Purdue University

Sometimes planetary physics is like being in a snowball fight. Most people, if handed an already-formed snowball, can use their experience and the feel of the ball to guess what kind of snow it is comprised of: packable and fluffy, or wet and icy.

Using nearly the same principles, planetary scientists have been able to study the structure of Europa, Jupiter’s icy moon.

Europa is a rocky moon, home to saltwater oceans twice the volume of Earth’s, encased in a shell of ice. Scientists have long thought that Europa may be one of the best places in our solar system to look for nonterrestrial life. The likelihood and nature of that life, though, heavily depend on the thickness of its icy shell, something astronomers have not yet been able to measure.

A team of planetary science experts including Brandon Johnson, an associate professor, and Shigeru Wakita, a research scientist, in the Department of Earth, Atmospheric, and Planetary Sciences in Purdue University’s College of Science, announced in a new paper published in Science Advances that Europa’s ice shell is at least 20 kilometers thick.

Adding ribociclib to hormone therapy reduces the risk of breast cancer recurrence

Photo Credit: National Cancer Institute

A new treatment approach that combines a targeted therapy drug with hormone therapy significantly increased the amount of time a person with stage 2 or 3 HR-positive, HER2-negative early breast cancer lives without the cancer returning, according to a new study co-led by UCLA Health Jonsson Comprehensive Cancer Center investigators.

The team found adding ribociclib, a drug that belongs to a class of CDK4/6 inhibitors, to standard hormone therapy not only improved invasive-free survival in women with this type of early-stage breast cancer, but also improves distant disease-free survival and recurrence-free survival.

The results were published today in the New England Journal of Medicine and findings were presented last year at the American Society of Clinical Oncology Annual Meeting in Chicago.

“We found that adding ribociclib to the standard hormone therapy resulted in a relative reduction in the recurrence rate by as much as 25%,” said first author of the study Dr. Dennis Slamon, chair of hematology-oncology at the David Geffen School of Medicine at UCLA and director of clinical and translational research at the UCLA Health Jonsson Comprehensive Cancer Center. “And that’s huge for this the group of patients, who make up 70% to 75% of breast cancer cases.”

Many patients with this type of breast cancer are treated with surgery, and in some cases with radiation and chemotherapy, followed by endocrine therapy for up to 10 years to help reduce their risk of recurrence.

Hypoxia is widespread and increasing in the ocean off the Pacific Northwest coast

In late August, OSU's Jack Barth and his colleagues deployed a glider that traversed Oregon’s near-shore waters from Astoria to Coos Bay and measured the oxygen levels through the water column, and beamed the data back to OSU computers.
Photo Credit: Courtesy of Jack Barth.

Low oxygen conditions that pose a significant threat to marine life are widespread and increasing in coastal Pacific Northwest ocean waters as the climate warms, a new study shows.

Researchers found that in 2021, more than half the continental shelf off the Pacific Northwest coast experienced the low-oxygen condition known as hypoxia, said the study’s lead author, Jack Barth of Oregon State University.

“We’ve known that low oxygen conditions are increasing based on single points of study in the past, but this confirms that these conditions are occurring across Pacific Northwest coastal waters,” said Barth, an oceanography professor in the College of Earth, Ocean, and Atmospheric Sciences. “The 2021 season was unusually strong compared to past years but with climate change, we are headed in a direction where this may be the norm.”

The new study, published recently in Nature Scientific Reports, is based on data collected by an unprecedented number of research vessels and autonomous underwater gliders that were collecting measurements in the ocean during summer 2021.

New technology improves space weather monitoring

The Compact Space Plasma Analyzer will improve space weather prediction.
Photo Credit: Courtesy of Los Alamos National Laboratory

Peaceful though it may seem from Earth, space is beset by “weather” that can prove perilous for the sensitive — and expensive — technology aboard the spacecraft and satellites increasingly populating the realms outside our atmosphere. To meet that challenge, Los Alamos National Laboratory researchers have developed the Compact Space Plasma Analyzer, a small and cost-efficient space sensor capable of measuring space weather, which will help protect technology in orbit.

“Space weather, which is made up of charged particles from the sun, presents a range of challenges concerning the design, development and operation of satellites and spacecraft,” said Carlos Maldonado, principal investigator of the Compact Space Plasma Analyzer and a researcher in the Lab’s Space Science and Applications group. “Of particular interest to the space community are the interactions between space systems operating in plasma environments, which can lead to potentially hazardous levels of differential charging and cause interference for GPS and communication signals.”

A long-standing goal in the space weather community is to advance the capability to predict space weather events days in advance, in the same way that terrestrial weather forecasting enables one to anticipate a week of sunshine or snow.

Natural recycling at the origin of life

Volcanic freshwater lakes, similar to those found in Iceland today, offered a favorable niche on an early earth. The low-salt, alkaline conditions enabled early RNA replication.
Photo Credit: © Dieter Braun

How was complex life able to develop on the inhospitable early Earth? At the beginning there must have been ribonucleic acid (RNA) to carry the first genetic information. To build up complexity in their sequences, these biomolecules need to release water. On the early Earth, which was largely covered in seawater, that was not so easy to do. In a paper recently published in the Journal of the American Chemical Society (JACS), researchers from the team of LMU professor Dieter Braun have shown that in RNA’s struggle with the surrounding water, its natural recycling capabilities and the right ambient conditions could have been decisive.

“The building blocks of RNA release a water molecule for every bond they form in a growing RNA chain,” explains Braun, spokesperson for the Collaborative Research Centre (CRC) Molecular Evolution in Prebiotic Environments and coordinator at the ORIGINS Excellence Cluster. “When, conversely, water is added to an RNA molecule, the RNA building blocks are fed back into the prebiotic pool.” This turnover of water works particularly well under low saline conditions with high pH levels. “Our experiments indicate that life could emerge from a very small set of molecules, under conditions such as those prevailing on volcanic islands on the early Earth,” says Adriana Serrão, lead author of the study.

Study reveals how pH affects the ability of ulcer bacteria to attach

Anna Åberg and Anna Arnqvist Björklund.
Photo Credit: Mattias Pettersson

A study by Anna Arnqvist's research group at Umeå University reveals molecular details about the gastric pathogen Helicobacter pylori's ability to bind to an inflamed stomach and how this is controlled by the stomach's pH. Increased understanding of how H. pylori bacteria can cause a persistent lifelong infection is an important piece of the puzzle in order to ultimately identify the characteristics that contribute to disease.

When the stomach becomes infected with the gastric pathogen Helicobacter pylori, the infection lasts for life if it is left untreated. The infection can cause peptic ulcer disease as well as stomach cancer. The environment within the stomach undergoes continuous changes, requiring the bacteria to adapt by adjusting the expression of certain proteins based on the prevailing conditions.

It is commonly assumed that the stomach has a low pH. However, the pH levels vary significantly, ranging from the highly acidic environment in the stomach lumen to largely neutral conditions at the outermost layer of the stomach epithelial cells, which is protected by a mucus layer. It is in the mucus layer or tightly attached to the outermost cell layer that most H. pylori bacteria are found. The expression of many genes is regulated in response to pH, causing the bacterium to produce varying amounts of proteins depending on the pH of its surroundings.

Oxford researchers uncover remarkable archive of ancient human brains

Fragments of brain from an individual buried in a Victorian workhouse cemetery (Bristol, UK), some 200 years ago. No other soft tissue survived amongst the bones, which were dredged from the heavily waterlogged grave.
Photo Credit: Alexandra L. Morton-Hayward.

A new study conducted by researchers at the University of Oxford has challenged previously held views that brain preservation in the archaeological record is extremely rare. The team carried out the largest study to date of the global archaeological literature about preserved human brains to compile an archive that exceeds 20-fold the number of brains previously compiled. The findings have been published today in the Proceedings of the Royal Society B.

Soft tissue preservation in the geological record is relatively rare, and, except where deliberate intervention halts the process of decay (for instance, during embalming or freezing), the survival of entire organs is particularly unusual. The spontaneous preservation of the brain in the absence of any other soft tissues - that is, the brain’s survival amongst otherwise skeletonized remains - has historically been regarded as a ‘one-of-a kind’ phenomenon. This new research reveals, however, that nervous tissues actually persist in much greater abundances than traditionally thought, assisted by conditions that prevent decay.

Tuesday, March 19, 2024

Craving snacks after a meal? It might be food-seeking neurons, not an overactive appetite

The discovery of a circuit in the brain of mice that makes them seek fatty food, even when they are not hungry, could have implications for future understanding of and treatment for human eating disorders.
Photo Credit: Annie Spratt

People who find themselves rummaging around in the refrigerator for a snack not long after they’ve eaten a filling meal might have overactive food-seeking neurons, not an overactive appetite.

UCLA psychologists have discovered a circuit in the brain of mice that makes them crave food and seek it out, even when they are not hungry. When stimulated, this cluster of cells propels mice to forage vigorously and to prefer fatty and pleasurable foods like chocolate over healthier foods like carrots.

People possess the same kinds of cells, and if confirmed in humans, the finding could offer new ways of understanding eating disorders.

The report, published in the journal Nature Communications, is the first to find cells dedicated to food-seeking in a part of the mouse brainstem usually associated with panic, but not with feeding.

“This region we’re studying is called the periaqueductal gray (PAG), and it is in the brainstem, which is very old in evolutionary history and because of that, it is functionally similar between humans and mice,” said corresponding author Avishek Adhikari, a UCLA associate professor of psychology. “Although our findings were a surprise, it makes sense that food-seeking would be rooted in such an ancient part of the brain, since foraging is something all animals need to do.”

Backyard insect inspires invisibility devices, next gen tech

Brochosomes are hollow, nanoscopic, soccer ball-shaped spheroids with through-holes that are produced by the common backyard insect, the leafhopper. Researchers found that the through-holes of these hollow buckyballs help reduce the reflection of light. This is the first biological example showing short wavelength, low-pass antireflection functionality enabled by through-holes and hollow structures.
Image Credit: Lin Wang and Tak-Sing Wong / Pennsylvania State University
(CC BY-NC-ND 4.0 DEED)

Leafhoppers, a common backyard insect, secrete and coat themselves in tiny mysterious particles that could provide both the inspiration and the instructions for next-generation technology, according to a new study led by Penn State researchers. In a first, the team precisely replicated the complex geometry of these particles, called brochosomes, and elucidated a better understanding of how they absorb both visible and ultraviolet light.

This could allow the development of bioinspired optical materials with possible applications ranging from invisible cloaking devices to coatings to more efficiently harvest solar energy, said Tak-Sing Wong, professor of mechanical engineering and biomedical engineering. Wong led the study, which was published in the Proceedings of the National Academy of Sciences (PNAS).

The unique, tiny particles have an unusual soccer ball-like geometry with cavities, and their exact purpose for the insects has been something of a mystery to scientists since the 1950s. In 2017, Wong led the Penn State research team that was the first to create a basic, synthetic version of brochosomes in an effort to better understand their function.

Researchers roll out a more accurate way to estimate genetic risks of disease

Illustration Credit: Ricardo Job-Reese, Broad Communications.

Researchers have developed statistical tools called polygenic risk scores (PRSs) that can estimate individuals’ risk for certain diseases with strong genetic components, such as heart disease or diabetes. However, the data on which PRSs are built is often limited in diversity and scope. As a result, PRSs are less accurate when applied to populations that differ demographically from the PRS training data.

A new scoring approach featured in Cell Genomics and developed by researchers at the Broad Institute of MIT and Harvard and Massachusetts General Hospital (MGH) uses a comprehensive approach to generate more accurate and informative PRSs. Aptly named PRSmix due to its ability to “mix” all previously developed PRSs for a given trait, the approach generates scores that estimate a patient’s genetic disease risk more accurately than PRSs generated from individual studies.

“A major challenge with PRSs is that they’re derived in one population and then unleashed broadly with the assumption that the scores can be generalized,” explained Pradeep Natarajan, the study’s corresponding author. Natarajan is an associate member in Broad's Cardiovascular Disease Initiative and director of preventive cardiology at MGH. “The overall motivation for this work is to better identify individuals who are prematurely at high risk for heritable conditions.”

Cranberries provide runners with an all-natural boost, according to new Concordia research

Speed, blood lactate and oxygen levels improve with daily extract consumption
Photo Credit: Rasa Kasparaviciene

Competitive athletes are always looking for an extra edge that can help them improve performance. According to a new study by Concordia researchers published in the journal Physical Activity and Nutrition, they can find one in the common cranberry.

In a series of trials involving trained distance runners, the researchers found that ingesting a cranberry supplement for 28 consecutive days led to noticeable improvements in both performance and muscle fatigue following 1,500-meter time trials. Reoxygenation rates were faster and running speeds improved by 1.5 per cent.

“When it comes to elite athletes, any advantage can make the difference between finishing fifth or on the podium,” says Andreas Bergdahl, an associate professor in the Department of Health, Kinesiology and Applied Physiology and the paper’s senior author.

Greenhouse gas emissions in Global South countries linked with IMF lending policies

New research by sociology professor Matthew Soener links loans from the International Monetary Fund to increased greenhouse gas emissions in Global South countries within several years. 
Photo Credit: Fred Zwicky

Greenhouse gas emissions significantly increase in countries in the Global South within a few years after initially borrowing from the International Monetary Fund using structural loans, but not when more flexible lending conditions are involved. 

However, with countries’ second or subsequent IMF loans, their emissions spike almost immediately, regardless of the lending conditions involved, a recent study suggests.

Structural loans, one of IMF’s two primary lending instruments, specify the precise changes borrowers are required to make to obtain the funds. By contrast, quantitative loans require that borrowers achieve quantifiable benchmarks – such as reducing their deficit by 5%, for example – but give them autonomy in deciding how they accomplish it, said study author Matthew Soener, a professor of sociology at the University of Illinois Urbana-Champaign.

Structural conditions impose coercive market constraints, reforms that pressure borrowers to increase their exports, indirectly raising countries’ greenhouse gas emissions through greater agricultural or manufacturing activities, Soener said.

“As a way to maintain growth and repay that loan, countries might decide, ‘Well, we can export more bananas, forest products or other agricultural products’ – or whatever specialty they might have,” he said. “In doing that, the country might be solving one problem, but they are causing another by increasing their greenhouse gas emissions.” 

Rice researchers develop 3D-printed wood from its own natural components

Researchers at Rice University have unlocked the potential to use 3D printing.
Photo Credit: Gustavo Raskosky/Rice University.

Researchers at Rice University have unlocked the potential to use 3D printing to make sustainable wood structures, offering a greener alternative to traditional manufacturing methods.

Wood has historically been marred by wasteful practices generated during shaping processes, driving up costs and environmental impact. Now researchers in materials science and nanoengineering at Rice have developed an additive-free, water-based ink made of lignin and cellulose, the fundamental building blocks of wood. The ink can be used to produce architecturally intricate wood structures via a 3D printing technique known as direct ink writing.

The work was recently published in the journal Science Advances.

“The ability to create a wood structure directly from its own natural components sets the stage for a more eco-friendly and innovative future,” said Muhammad Rahman, an assistant research professor of materials science and nanoengineering at Rice. “It heralds a new era of sustainable 3D-printed wood construction.”

The implications are far-reaching, potentially revolutionizing industries such as furniture and construction.

Cells harvested from urine may have diagnostic potential for kidney disease, find scientists

Image Credit: AI generated / Gemini Advance

Genes expressed in human cells harvested from urine are remarkably similar to those of the kidney itself, suggesting they could be an important non-invasive source of information on the kidney.

The news offers hope that doctors may one day be able to investigate suspected kidney pathologies without carrying out invasive procedures such as biopsies, raising the tantalizing prospect of earlier and simpler disease detection.

The impact of late detection of kidney disease can be severe and can lead to serious and sometimes life-threatening complications.

The team led by University of Manchester scientists measured the levels of approximately 20,000 genes in each cellular sediment sample of urine using a technique called transcriptomics.

The British Heart Foundation-funded study benefited from access to the world's largest collection of human kidney samples collected after surgery or kidney biopsy conducted before transplantation, known as the Human Kidney Tissue Resource, at The University of Manchester.

They extracted both DNA and RNA from each sample and connected information from their analysis, together with data from previous large-scale analyses of blood pressure (called genome-wide association studies), using sophisticated computational methods.

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