Parkinson’s: are our neurons more vulnerable at night?

More dopaminergic neurons in the adult Drosophila brain survive in control flies (left) than in flies mutant for the circadian cycle (right).
Image Credit: © Lou Duret

Disturbances in sleep patterns and the internal biological clock are frequently associated with Parkinson’s disease. However, the link between biological rhythm and neuronal degeneration remains unclear. A team from the University of Geneva (UNIGE) investigated the destruction of neurons at different times of the day, using the fruit fly as a study model. The scientists discovered that the type of cellular stress involved in Parkinson’s disease was more deleterious to neurons when it occurred at night. This work can be read in the journal Nature Communications.

Parkinson’s disease is a progressive neurodegenerative disorder characterized by the destruction of certain neurons in the brain: dopamine neurons. The main symptoms of this disease are tremors, slowness of movement and muscular stiffness. Epidemiological studies show that other disorders may be associated, such as disturbances of sleep and of the circadian cycle.

This cycle, defined by the alternate periods of wakefulness and sleep, lasts around 24 hours and constitutes the human body’s internal clock that regulates almost all its biological functions. In particular, the circadian clock controls the secretion of the ‘‘sleep hormone’’(melatonin) at the end of the day, variations in body temperature (lower in the early morning and higher during the day), and metabolism in periods of fasting (during sleep) or energy intake (during daytime meals).

Topological Insulator Catalysts for High-Yield Room-Temperature Synthesis of Organoureas

The unique quantum properties of bismuth selenide make it a promising catalyst for the synthesis of organic ureas, as demonstrated by scientists at Tokyo Tech. Thanks to its topological surface states, the proposed catalyst exhibits remarkably high catalytic activity and durability when used for the synthesis of various urea derivatives, which are widely utilized as nitrogen fertilizers.

Synthetic fertilizers, one the most important developments in modern agriculture, have enabled many countries to secure a stable food supply. Among them, organic ureas (or organoureas) have become prominent sources of nitrogen for crops. Since these compounds do not dissolve immediately in water, but instead are slowly decomposed by soil microorganisms, they provide a stable and controlled supply of nitrogen, which is crucial for plant growth and function.

However, traditional methods to synthesize organoureas are environmentally harmful due to their use of toxic substances, such as phosgene. Although alternative synthesis strategies have been demonstrated, these either rely on expensive and scarce noble metals or employ catalysts that cannot be reused easily.

Low-grade intestinal inflammation a long time after radiotherapy

Photo Credit: Jo McNamara

Patients who have undergone pelvic radiotherapy may live with low-grade chronic inflammation of the lower intestine 20 years after the treatment. This has been shown in a study by researchers at the University of Gothenburg.

Radiotherapy is often necessary to cure or slow down cancer. Even though today’s radiotherapies feature a high level of precision, healthy tissue in and around the radiation field is still affected. This study highlights a previously unknown side effect of radiotherapy to the lower abdomen.

The mucous membrane of the large intestine is normally protected against contact with bacteria in feces by a thin barrier of mucus. In the current study, researchers at the University of Gothenburg have shown that radiotherapy to the pelvic area affects this thin layer of mucus, allowing bacteria to come into contact with cells on the surface of the intestine. This could be a reason for the low-grade inflammation that the researchers also found in intestines that had been exposed to radiotherapy several years previously.  

“Anti-tangle” molecule could aid search for new dementia treatments, say scientists

Scientists at Bath have found a way of blocking the protein tangles that are associated with dementia diseases
Photo Credit: NCI

Scientists have identified a molecule that can prevent tangling of a brain protein that is linked to diseases such as Parkinson’s. The findings may provide insights into new ways of treating or diagnosing the early stages of dementia.

Alpha-synuclein, a protein found in brain cells, is commonly associated with neurodegenerative diseases such as Parkinson's, a debilitating neurological disorder affecting millions worldwide.

Like all proteins, it is made up of a long strand of molecules called amino acids. When it’s made, this strand folds in on itself to form a complex but precise 3D shape, made up of sub-structures and loops.

In healthy individuals, alpha-synuclein interacts with cell membranes where it plays a role in how brain cells (neurons) communicate with each other, but as a person ages, the 3D shape of the protein can malformed, or “misfolded”, causing it to start sticking together to form toxic clumps in the brain.

Over time these clumps continue to stack, forming fibers that can interfere with the protein’s normal role, eventually killing brain cells, contributing to the development of Parkinson's and related dementia diseases.

Plants on Ash Dumps Experience Nutrient Deficiency

Scientists studied two ash dumps in the Middle Urals.
Photo Credit: From the personal archive of Anna Betekhtina

Many nutrients, especially nitrogen, are not available to plants on ash dumps, biologists from the Ural Federal University and the Institute of Plant and Animal Ecology of the Ural Branch of the Russian Academy of Sciences (IPAE UB RAS) have found out. Despite the fact that nitrogen accumulates in the soil of ash dumps as a result of overgrowth, its availability to plants is very low. This situation is unique, because usually the nitrogen content in the soil is directly related to nitrogen content in plants. The description of chemical analysis of plants and soils of ash dumps scientists published in the journal "Ecology". 

"Nitrogen is one of the most important elements of plant nutrition, and its availability determines the productivity of plant communities. At various natural sites, a single pattern has been shown: when the nitrogen content in the soil increases, its amount in plants also increases. Such dynamics is described in many works of Russian and foreign scientists. However, our results turned out to be quite different. The results obtained on other natural objects cannot be transferred to technogenic landscapes, such as ash dumps", explains Anna Betekhtina, senior researcher of the Laboratory of Restorative Ecology at UrFU.

Two-decade monitoring of M87 unveils a precessing jet connecting to a spinning black hole

Schematic representation of the tilted accretion disk model. The black hole spin axis is assumed to align vertically. The jet direction stands almost perpendicular to the disk plane. The misalignment between the black hole spin axis and disk rotation axis triggers the precession of disk and jet.
Illustration Credit: Yuzhu Cui et al. (2023), Intouchable Lab@Openverse and Zhejiang Lab.

In a tale of cosmic patience spanning more than two decades, it has been discovered that the nearby radio galaxy M87, located 55 million light-years from the Earth and harboring a black hole 6.5 billion times more massive than the Sun, exhibits an oscillating jet. This investigation found the jet swinging up and down with an amplitude of about 10 degrees.

The international collaboration team consisting of researchers from 45 institutions around the world, including Dr. Satoko Sawada-Satoh of Osaka Metropolitan University’s Graduate School of Science, analyzed data observed from 2000 to 2022. They unveiled a recurring 11-year cycle in the precessing motion of the jet base, as predicted by Einstein’s general relativity. This work successfully linked the dynamics of the jet with the central supermassive black hole, offering evidence for the existence of M87’s black hole spin.

Noninvasive, ultrasound-based brain biopsy is feasible

Graduate student Lu Xu wears a device designed by engineers, at Washington University in St. Louis, that targets ultrasound waves to precise spots in the brain. Such targeting is the first step in a sonobiopsy, a noninvasive technique invented by Washington University researchers that uses ultrasound and microbubbles to release biomolecules from brain tumors. The biomolecules then can be collected via a blood draw, analyzed and used to inform treatment decisions. Xu is part of a research team that demonstrated that sonobiopsy is safe and feasible for use in people.
Photo Credit: Courtesy of Hong Chen

The blood-brain barrier, the body’s way of shielding sensitive brain tissue from viruses, toxins and other harmful substances in the blood, can pose a problem for physicians caring for patients with suspected brain diseases such as cancer. Molecular and genetic information would be invaluable for confirming a diagnosis and guiding treatment decisions, but such molecules are normally confined to the brain by the barrier. Neurosurgeons routinely perform surgical brain biopsies to obtain this data on brain tumors, but such procedures carry risks and are not feasible for all tumors or for many other kinds of brain diseases.

Researchers at Washington University in St. Louis have developed an anatomically precise technique called sonobiopsy that uses ultrasound and microbubbles to disrupt the barrier temporarily and allow RNA, DNA and proteins from the brain to spill out into the blood, where they can be detected and analyzed. The researchers developed and previously tested the technique in animals. In a new study, available online in the journal NPJ Precision Oncology, they showed that the technique is feasible and safe for use in people, and could open the door to noninvasive biopsies for suspected brain tumors and other brain diseases.

Important additional driver of insect decline identified

The grape wood borer (Chlorophorus varius) is one of over 33,000 insect species in Germany. The development of the insect biomass depends significantly on weather conditions, as a study published in "Nature" in 2023 shows.
Photo Credit: Didier Descouens
(CC BY-SA 3.0)

Combinations of unfavorable weather conditions over several years can cause a decline in insect biomass. This is shown by a study published in "Nature" with TUD being involved.

Insects react sensitively when temperature and precipitation deviate from the long-term average. In an unusually dry and warm winter, their survival probabilities are reduced; in a wet and cold spring, hatching success is impaired. A cool, wet summer hampers bumblebees and other flying insects from reproducing and foraging.

If several such weather anomalies occur in combination and over several years, this can lead to a decline in insect biomass on a large scale and in the long term. This is shown in a new report in the journal Nature.

According to the report, weather conditions and accumulations of unfavorable weather anomalies in the course of climate change can be important drivers of global insect decline. Only insect populations with a large number of individuals, as found in sufficiently large and high-quality habitats, appear to be able to survive under such adverse conditions.

Saturated fat may interfere with creating memories in aged brain

The study in cell cultures found the omega-3 fatty acid DHA, found in fish and a common supplement, may help protect the brain from an unhealthy diet’s effects by curbing fat-induced inflammation at the cellular source.
Photo Credit: Leohoho

New research hints at a few ways fatty foods affect cells in the brain, a finding that could help explain the link between a high-fat diet and impaired memory – especially as we age.

The Ohio State University study in cell cultures found the omega-3 fatty acid DHA may help protect the brain from an unhealthy diet’s effects by curbing fat-induced inflammation at the cellular source. 

Separate experiments using brain tissue from aging mice showed a high-fat diet may lead specific brain cells to overdo cell-signaling management in a way that interferes with the creation of new memories. 

The same lab found in an earlier study in aging rats that a diet of highly processed ingredients led to a strong inflammatory response in the brain that was accompanied by behavioral signs of memory loss – and that DHA supplementation prevented those problems. 

“The cool thing about this paper is that for the first time, we’re really starting to tease these things apart by cell type,” said senior author Ruth Barrientos, an investigator in Ohio State’s Institute for Behavioral Medicine Research and associate professor of psychiatry and behavioral health and neuroscience in the College of Medicine. 

Tree rings reveal a new kind of earthquake threat to the Pacific Northwest

Price Lake, in the eastern Olympic Mountains, formed when the Saddle Mountain fault impounded a stream and flooded the forest. Lead author Bryan Black and his team of divers collected the samples using an underwater hydraulic chainsaw.
Photo Credit: Bryan Black

In February, a 7.8-magnitude earthquake shook the Turkey-Syria border, followed by one nearly as large nine hours later. Shallow faults less than 18 miles beneath the surface buckled and ruptured, causing violent focused quakes that leveled thousands of buildings and killed tens of thousands.

Similar shallow faults ruptured about 1,000 years ago in the Puget Lowlands in western Washington, according to new University of Arizona-led research. Tree rings helped pinpoint that the seismic event occurred in late A.D. 923 or early 924. Their findings mean that a repeat event has the potential to again shake the region that is now home to over 4 million people, including Seattle, Tacoma and Olympia. The results were published in the journal Science Advances.

The ancient quake was either the result of all the shallow faults in the region rupturing together to produce an estimated 7.8-magnitude earthquake or – like in Turkey and Syria – twin quakes that occurred back-to-back with estimated magnitudes of 7.5 and 7.3, researchers found. Shallow faults typically result in more violent and focused shaking than earthquakes generated from other geological configurations.