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Poor sleep and other issues with circadian rhythm are common for people with Alzheimer’s disease. Now researchers may have a clue to why.


“If your circadian clock is not quite right for years and years—you routinely suffer from disrupted sleep at night and napping during the day—the cumulative effect of chronic dysregulation could influence inflammatory pathways such that you accumulate more amyloid plaques,” says Erik Musiek. (Credit: Getty Images)

Fractured sleep, daytime sleepiness, and other signs of disturbance in one’s circadian rhythm are common complaints of people with Alzheimer’s disease, and the problems only get worse as the disease progresses.

Researchers at Chalmers University of Technology, with collaborators at Technische Universität Berlin, have demonstrated the shortest wavelength ever reported of a vertical-cavity surface-emitting laser (VCSEL). This can pave the way for future use in, for example, disinfection and medical treatment. The results were recently published in the scientific journal ACS Photonics.

“Although there is still much work to be done, especially to enable electrically driven devices, this demonstration provides an important building block for the realization of practical VCSELs covering the major part of the UV spectral range,” says Filip Hjort, Ph.D. student at the Photonics Laboratory at MC2 and first author of the article.

A vertical-cavity surface-emitting lasers (VCSEL) is a compact semiconductor laser and has seen widespread application in, for example, facial recognition in smartphones and for optical communication in data centers. So far, these lasers are only available commercially with red and , but also other visible-emitting VCSELs, that could find applications in adaptive headlamps for cars or projection displays, will soon be commercialized.

Electricity is a key ingredient in living bodies. We know that voltage differences are important in biological systems; they drive the beating of the heart and allow neurons to communicate with one another. But for decades, it wasn’t possible to measure voltage differences between organelles—the membrane-wrapped structures inside the cell—and the rest of the cell.

A pioneering technology created by UChicago scientists, however, allows researchers to peer into cells to see how many different organelles use voltages to carry out functions.

“Scientists had noticed for a long time that charged dyes used for staining cells would get stuck in the mitochondria,” explained graduate student Anand Saminathan, the first author for the paper, which was published in Nature Nanotechnology. “But little work has been done to investigate the membrane potential of other organelles in live cells.”

Follow the links in the story for sources, the text is in red. A new strain of COVID-19 is causing a wave of new lockdowns in London and travel restrictions for those coming from the U.K. because some are worried that this may be an even more contagious version of the coronavirus. Experts say it’s definitely something to watch out for, but it’s not clear whether or not this variant is actually more transmissible—and there’s no reason to think the current COVID-19 vaccines won’t be effective against it. So what exactly is different about this new strain of COVID-19? Well, this variant (also called B. 1. 1. 7.) has a few mutations, 17 to be exact. Not all of them are concerning, but a few are. The mutations that have experts a little on edge have to do with genes that encode the virus’s spike protein, which is located on the surface of the virus and is the piece of the virus that helps it actually bind to human cells. (That’s the first step in becoming infected.) One of these mutations (called N501Y) may make it easier for the spike protein to bind to the receptors on our cells, Science explains. Another mutation (called 69-70del) affects the number of amino acids (the building blocks that make up a protein) in the spike protein, and variants with this mutation have been previously identified in some immunocompromised people whose bodies were unable to muster the necessary immune response to protect them from the virus.


It’s causing new lockdowns and travel restrictions.

Federal officials are disappointed to find that the monoclonal antibody drugs they’ve shipped across the country aren’t being used rapidly.

These drugs are designed to prevent people recently diagnosed with COVID-19 from ending up in the hospital. But hospitals are finding it cumbersome to use these medicines, which must be given by IV infusion. And some patients and doctors are lukewarm about drugs that have an uncertain benefit.

Doctors hope that as word gets out, more people will end up trying these drugs. They are provided to health systems free by the federal government, but it costs money to administer the medication. At first, Medicare set a price that would require many patients to pay a $60 copay, but the Centers for Medicare and Medicaid Services later found a way to waive that fee.


Monoclonal antibodies to prevent severe COVID-19 aren’t being used as widely as expected. Medical staff shortages and patient transportation problems are two of the reasons.

A team of Johns Hopkins University researchers has developed a new software that could revolutionize how DNA is sequenced, making it far faster and less expensive to map anything from yeast genomes to cancer genes.

The , detailed in a paper published in Nature Biotechnology, can be used with portable sequencing devices to accelerate the ability to conduct genetic tests and deliver diagnoses outside of labs. The new technology targets, collects and sequences without sample preparation and without having to map surrounding genetic material like standard methods require.

“I think this will forever change how DNA sequencing is done,” said Michael C. Schatz, a Bloomberg Distinguished Associate Professor of Computer Science and Biology and senior author of the paper.

Summary: Artificial intelligence technology redesigned a bacterial protein that helps researchers track serotonin in the brain in real-time.

Source: NIH

Serotonin is a neurochemical that plays a critical role in the way the brain controls our thoughts and feelings. For example, many antidepressants are designed to alter serotonin signals sent between neurons.

In an article in Cell, National Institutes of Health-funded researchers described how they used advanced genetic engineering techniques to transform a bacterial protein into a new research tool that may help monitor serotonin transmission with greater fidelity than current methods. Preclinical experiments, primarily in mice, showed that the sensor could detect subtle, real-time changes in brain serotonin levels during sleep, fear, and social interactions, as well as test the effectiveness of new psychoactive drugs.

“Once they are ingested, up to 90% of the plastic fragments that reach the intestine are excreted. However, one part is fragmented into nanoplastics which are capable, due to their small size and molecular properties, to penetrate the cells and cause harmful effects. The study establishes that alterations in food absorption have been described, as well as inflammatory reactions in the intestinal walls, changes in the composition and functioning of the gut microbiome, effects on the body’s metabolism and ability to produce, and lastly, alterations in immune responses. The article alerts about the possibility of a long-term exposure to plastic, accumulated throughout generations, could give way to unpredictable changes even in the very genome, as has been observed in some animal models.”


We live in a world invaded by plastic. Its role as a chemically stable, versatile and multi-purpose fostered its massive use, which has finally translated into our current situation of planetary pollution. Moreover, when plastic degrades it breaks into smaller micro and nanoparticles, becoming present in the water we drink, the air we breathe and almost everything we touch. That is how nanoplastics penetrate the organism and produce side effects.

A revised study led by the Universitat Autónoma de Barcelona (UAB), the CREAF and the Centre for Environmental and Marine Studies (CESAM) at the University of Aviero, Portugal, and published in the journal Science Bulletin, verifies that the nanoplastics affect the composition and diversity of our intestinal microbiome and that this can cause damage to our health. This effect can be seen in both vertebrates and invertebrates, and has been proved in situations in which the exposure is widespread and prolonged. Additionally, with alteration of the gut microbiome come alterations in the immune, endocrine and and therefore, although not enough is known about the specific physiological mechanisms, the study alerts that stress to the gut microbiome could alter the health of humans.

The health effects of being exposed to nanoplastics was traditionally evaluated in aquatic animals such as molluscs, crustaceans and fish. Recent in vitro analyzes, using cell cultures of fish and mammals, has allowed scientists to analyze the changes in gene expression associated with the presence of nanoplastics from a toxicological viewpoint. The majority of neurological, endocrine and immunological tracts in these vertebrates are very similar to those of humans, and therefore authors warn that some of the effects observed in these models could also be applied to humans. Understanding and analyzing the process through which these plastic fragments penetrate the organism and harm it is fundamental, as is determining precisely the amount and typology of nanoplastics polluting the environment.