Scientists from NUS and NUHS identify predictive blood biomarker for cognitive impairment and dementia

Prof Barry Halliwell (left) and Dr Irwin Cheah (right), together with their collaborators from the National University Health System, have discovered that low levels of ergothioneine in blood plasma may predict an increased risk of cognitive impairment and dementia.
Photo Credit: National University of Singapore

Identification of elderly persons at risk of developing cognitive impairment and dementia could be made possible by examining ergothioneine levels in the blood

A recent study by a team comprising researchers from the National University of Singapore (NUS) and the National University Health System (NUHS) revealed that low levels of ergothioneine (ET) in blood plasma may predict an increased risk of cognitive impairment and dementia, suggesting possible therapeutic or early screening measures for cognitive impairment and dementia in the elderly.

The research teams were led by Professor Barry Halliwell from the Department of Biochemistry under the NUS Yong Loo Lin School of Medicine and Associate Professor Christopher Chen and Dr Mitchell Lai from the Memory, Ageing and Cognition Centre under NUHS. The results of their most recent study were published in the scientific journal Antioxidants.

Samples From Asteroid Ryugu Help Us Learn About Earth's Origins

The elemental composition of the Earth comes from its fiery past, through accretion of various solar system objects. New samples collected by the Hayabusa2 space mission provide insight into the origins of moderately volatile elements such as zinc and copper. Tokyo Tech researchers have linked the material from the Cb-type asteroid, Ryugu, to the elemental composition of the Earth. Their results suggest that Ryugu-type material played a significant role in the genetic heritage of the Earth's elemental composition.

Understanding the origins of Earth's elemental composition offers a glimpse into the history of our planet. One way to learn about this is to investigate the meteorites that would have similar composition with materials that contributed to the accretion of planet Earth in its early development. Meteorites are divided into multiple classes based on their composition. The most primitive and common of these classes includes chondrites, which further includes carbonaceous chondrites (CCs). Of these, Ivuna-type (CI) CCs have an elemental composition that is nearly identical with that of the solar photosphere, which therefore can be used as a key reference for understanding how early solar system processes shaped planets and their building blocks. The Hayabusa2 spacecraft's mission was to collect samples from the Cb-type asteroid (162173), Ryugu. As the elemental composition of returned Ryugu samples is unaffected by further terrestrial processes, the two successful sampling events on Ryugu offer a plethora of unprecedented information.

Critical illness myopathy common condition in intensive care patients

Lars Larsson performing experiments on the ICU models.
Photo Credit: Ya Wen

Critical illness myopathy (CIM) is a common complication affecting ventilator-treated intensive care patients, which can lead to increased mortality/morbidity, prolonged hospital care, impaired patient quality of life, and increased healthcare costs. reported molecular pathogenesis of CIM during prolonged ICU stay, and potential diagnostic biomarkers and therapeutic targets. The study was recently published in Journal of Cachexia, Sarcopenia and Muscle.

Over the past 65 years, intensive care units (ICUs) have undergone a significant development that has resulted in improved survival rates. But life-saving efforts are also accompanied by negative consequences for ICU patients, affecting skeletal muscle systems, including the critical illness myopathy (CIM) with muscle wasting and paralysis/paresis. The incidence of CIM is about 30% among ICU patients, and almost 100% in neuro-ICU patients exposed to prolonged controlled mechanical ventilation. Moreover, the negative consequences have become increasingly apparent during the COVID-19 pandemic.

New study finds logged tropical forests are surprisingly vibrant and need protection

Logged tropical forests are surprisingly vibrant and need protection.
Photo Credit: Zoe G Davies

A new study by researchers at the University of Oxford, finds that logged rainforests are treasure-troves of healthy ecological function and should not be written off for oil palm plantations.

The study examines the flow of ecological energy across old-growth forests, logged forests and oil palm

Surveys mammal and bird species across these landscapes to calculate food energetic pathways: how photosynthetic energy cascades from sunlight to be distributed among organisms

Relative to energy flow in old-growth forests, study finds 2.5 times more total energy flows in logged forests

The study findings question the use of the word “degraded” to describe logged tropical forests

Why aren’t all black bears black?

Cinnamon Black Bear
Resized Image using AI by SFLORG
Photo Credit: Appalachian Encounters / CC BY 2.0

Sometimes a name is just a name. Take bears, for example. In Yellowstone National Park, black bears outnumber their brownish-colored grizzly bear cousins, and in coastal areas of the Pacific Northwest, if someone says “brown bear,” they mean grizzly bear. But not all brown bears are grizzly bears.

American black bears (Ursus americanus), which one would logically assume are, well, black, actually come in a range of colors, including brown (also known as cinnamon), blond, or bluish-grey. Others have coats that are a mixture of several colors. So, how do you tell a cinnamon-colored Ursus americanus from its brown (grizzly) Ursus arctos cousin? Differences in body shape and size can be subtle. One hypothesis for the cinnamon color of Ursus americanus is that it mimics the appearance of a grizzly bear, helping with camouflage or defense.

Now, researchers at the HudsonAlpha Institute for Biotechnology, the University of Memphis, and the University of Pennsylvania, have discovered what causes the cinnamon color, which sheds some light on this color confusion.

UCLA-developed soft brain probe could be a boon for depression research

 Illustration of the soft probe with aptamer biosensors implanted in the brain.
Illustration Credit: Zhao, et al., 2022

Anyone familiar with antidepressants like Prozac or Wellbutrin knows that these drugs boost levels of neurotransmitters in the brain like serotonin and dopamine, which are known to play an important role in mood and behavior.

It might come as a surprise, then, that scientists still have very little data about the specific relationship between neurotransmitters — chemicals that relay messages from one brain cell to others — and our psychological states. Simply put, monitoring fluctuations of these neurochemicals in living brains has proved a persistent challenge.

Now, for the first time, UCLA scientists have attached nanoscale biochemical sensors, which are tuned to identify specific neurotransmitters, to a soft, implantable brain probe in order to continuously monitor these chemicals in real time. The new brain probe, described in a paper published in ACS Sensors, would allow scientists to track neurotransmitters in laboratory animals — and, ultimately, humans — during their day-to-day activities.

Researchers have identified the origins of a serious illness in children

Egle Kvedaraite, doctor and researcher.
Photo Credit: Sebastien Teissier.

The origins of the serious cancer-like disease LCH have been identified by researchers from Karolinska Institutet in collaboration with Karolinska University Hospital. The findings presented in Science Immunology may lead to new, targeted treatments.

Langerhans’ Cell Histiocytosis (LCH) is a serious type of cancer-like disease that mainly affects children and can be fatal in severe cases. About five to ten children get the disease in Sweden every year, usually before the age of ten.  

The immune cells are affected by cancer mutations

LCH is a disease in which the cancer mutation occurs in the immune cells, which otherwise have the task of detecting and eliminating cancer cells. 

New Research on Antibiotic Resistant Bacteria May Be A Step Toward New Treatments for Infections

 From left to right: NSU Students Gabriela Diaz Tang, Estefania Marin Meneses
Credit: Nova Southeastern University

Antibiotic resistant bacteria pose one of the greatest threats to global public health. In 2019, deaths due to antibiotic resistant bacteria outpaced deaths due to HIV and malaria. Given the lack of innovation in the discovery of new antibiotics, it is critical to determine the mechanisms by which bacteria tolerate existing antibiotics so that we can improve their effectiveness.

One way that bacteria can tolerate antibiotics is through the inoculum effect. Essentially, the higher the density of bacteria in an infection, the more antibiotics are required to treat the infection. While the inoculum effect has been observed for nearly all known antibiotics, and has been documented since the 1960s, a common mechanism to explain inoculum effect for multiple antibiotics has not been found.

Scientists recently discovered that interactions between how fast bacteria grow and the amount of energy (or metabolism) bacteria have can explain the inoculum effect for multiple antibiotics and bacteria species. This new research also shows that providing different nutrients to the bacteria that change growth rate and energy levels can eliminate the inoculum effect.

Scientists discover what was on the menu of the first dinosaurs

Early dinosaurs and their diets. Lesothosaurus is an omnivore, Buriolestes is a carnivore and Thecodontosaurus is an herbivore
Illustration Credit: Gabriel Ugueto

The earliest dinosaurs included carnivorous, omnivorous and herbivorous species, according to a team of University of Bristol paleobiologists.

By looking at the tooth shapes of the earliest dinosaurs and simulating their tooth function with computational modelling, experts were able to compare them to living reptiles and their diets. Their findings, published today in Science Advances, show that many groups of plant-eating dinosaurs were ancestrally omnivorous and that the ancestors of our famous long-necked herbivores, such as Diplodocus, ate meat. This ability to diversify their diets early in their evolution likely explains their evolutionary and ecological success.

The earliest dinosaurs are enigmatic: they were much smaller than their later relatives and for most of the Triassic they were in the shadow of crocodile-like reptiles. It is unknown how diverse they were in terms of diets and ecology, but scientists know something must have happened in the Triassic that allowed dinosaurs to endure the Triassic–Jurassic mass extinction and adapt in its aftermath, becoming the dominant group for the rest of the Mesozoic.

Rosenstiel marine researcher identifies new Bottlenose dolphin subspecies

New subspecies, called the Eastern Tropical Pacific bottlenose dolphin (Tursiops truncatus nuuanu), is smaller than other common bottlenose dolphins.   
Photo Credit: NOAA/NMFS/SWFSC.

A marine researcher at the University of Miami Rosenstiel School of Marine, Atmospheric, and Earth Science has identified a new bottlenose dolphin subspecies found only in the eastern tropical Pacific Ocean. “While there is a common belief that all dolphin species are already known, improvements in technologies and methodologies are helping to reveal a greater biodiversity in more recent years,” said Ana Costa, Ph.D., a Rosenstiel lecturer specializing in marine mammalogy.

After examining and analyzing a series of specimens, Costa and collaborators of the National Oceanic and Atmospheric Administration, found that the new subspecies, called the Eastern Tropical Pacific bottlenose dolphin (Tursiops truncatus nuuanu), is smaller than other common bottlenose dolphins. These dolphins likely prefer deep offshore waters between southern Baja California and the Galapagos Islands, she added.

Bird Diversity Increased in Severely Burned Forests of Southern Appalachian Mountains

Forest burned in high-severity wildfire.
Photo Credit: Chris Moorman

A new study found bird diversity increased in North Carolina mountain forest areas severely burned by wildfire in 2016, reinforcing that while wildfire can pose risks to safety and property, it can be beneficial to wildlife. The study results could help forest managers better predict bird responses to wildfire, and manage forests to benefit birds.

“It’s important for us to understand the relationships between animals and wildfire dynamics as the climate changes because predictions show more of these high-severity wildfires across the landscape in the future,” said study co-author Chris Moorman, professor of forestry and environmental resources at North Carolina State University.

Wildfires burned more than 235 square miles of forest in the southern Appalachians in the fall of 2016, following a period of dry conditions and acts of arson. In the study published in the journal Forest Ecology and Management, researchers tracked different levels of burn severity in three forest regions of the Nantahala National Forest in western North Carolina.

Astronomers discover clues about stellar ‘glitching’

Stars that experience structural "glitches" during their lifetimes may be more common than first thought.

Astronomers have found a way to peer into the physics of some of the brightest stars in the sky.

Using data from NASA’s Kepler space telescope, an international team of researchers has found new evidence that red giants, dying stars that have exhausted their supply of hydrogen and are in the final stages of stellar evolution, often experience large-scale structural variations, or what are known as “glitches” deep inside their inner core.

The stellar glitches popularized in the media have to do with a star’s rotation, but lead author Mathieu Vrard studies a different kind of defect. The glitches in this study can affect a star’s oscillations, or the frequencies and paths that sound waves travel when passing through a star.

Red clump stars, helium-core burning objects, are often used in astrophysical studies as probes of distance to measure aspects like galaxy density, and to learn more about the physical processes behind stellar chemical evolution. So, it’s vital that scientists understand why these discontinuities happen, said Vrard, a postdoctoral research associate in astronomy at the Ohio State University.

“By analyzing these variations, we can use them to obtain not only the global parameters of the star, but also information on the precise structure of those objects,” he said.

A poison helps to understand hydrogen-producing biocatalysts

Thomas Happe researches biocatalysts that can produce hydrogen in an environmentally friendly way.
 Photo Credit: RUB, Marquard

The toxic cyanide molecule attacks the enzymes, but also enables new insights into catalysis.

In nature, certain enzymes, so-called hydrogenases, are able to produce molecular hydrogen (H2) to produce. Special types of these biocatalysts, so-called [FeFe] hydrogenases, are extremely efficient and therefore of interest for bio-based hydrogen production. Although science already knows a lot about how these enzymes work, some details have not yet been fully clarified. The photobiotechnology working group at the Ruhr University Bochum around Dr. Jifu Duan and Prof. Dr. Close Thomas Happe. The researchers showed that external cyanide binds to the [FeFe] hydrogenases and inhibits hydrogen formation. They were able to demonstrate a structural change in the proton transport path that helps to understand the coupling of electron and proton transport. They report in the journal Angewandte Chemie.

Scientists use materials to make stem cells behave like human embryos

Stem cells confined in a circular shape on a soft gel display characteristic of embryonic development.
Photo Credit: University of New South Wales

A serendipitous discovery in the lab has the potential to revolutionize embryo models and targeted drug therapies.

Materials scientists at UNSW Sydney have shown that human pluripotent stem cells in a lab can initiate a process resembling the gastrulation phase – where cells begin differentiating into new cell types – much earlier than occurs in mother nature.

For an embryo developing in the womb, gastrulation occurs at day 14. But in a lab at UNSW’s Kensington campus, Scientia Associate Professor Kris Kilian oversaw an experiment where a gastrulation-like event was triggered within two days of culturing human stem cells in a unique biomaterial that, as it turned out, set the conditions to mimic this stage of embryo development.

“Gastrulation is the key step that leads to the human body plan,” says A/Prof. Kilian.

“It is the start of the process where a simple sheet of cells transforms to make up all the tissues of the body – nerves, cardiovascular and blood tissue and structural tissue like muscle and bone. But we haven’t really been able to study the process in humans because you can’t study this in the lab without taking developing embryonic tissue.

Untangling the Evolution of Complex Life

Dartmouth researchers report octopuses have high numbers of molecules linked to advanced cognition.
Photo Credit: Diane Picchiottino

Octopuses have captured the attention of scientists and the public with their remarkable intelligence, including the use of tools, engaging in creative play and problem-solving, and even escaping from aquariums. Now, their acuity may provide a critical link in understanding the evolution of complex life and cognition, including the human brain.

An international team led by researchers at Dartmouth and the Max Delbrück Center in Germany report in the journal Science Advances that octopuses are the first known invertebrates—creatures that lack a backbone and constitute roughly 95% of animal species—to contain a high number of gene-regulating molecules known as microRNAs.

The genes of two octopus species show an increase in microRNAs—which are linked to the development of advanced cells with specific functions—over evolutionary time that has so far only been found in humans, mammals, and other vertebrates.