A DNA barcoding system enables high-throughput in vivo screening of mitochondrial-targeting gold nanoparticles. Thirty nanoparticle types with varied shapes, sizes, and ligands are individually barco…
Get the latest international news and world events from around the world.
The universe is humming with ripples in spacetime: Scientists just doubled our catalog of black hole and neutron star collisions
“The message from this catalog is: We are expanding into new parts of what we call ‘parameter space’ and a whole new variety of black holes,” LVK member Daniel Williams, of the University of Glasgow in the U.K., said in the statement. “We are really pushing the edges, and are seeing things that are more massive, spinning faster, and are more astrophysically interesting and unusual.”
The catalog also demonstrates just how sensitive the LVK detectors have become. Some of the neutron star mergers occurred up to 1 billion light-years away, while some of the black hole mergers occurred up to 10 billion light-years away. These detections have allowed scientists to test the theory that first predicted the existence of both black holes and gravitational waves, Einstein’s magnum opus theory of gravity, general relativity.
A new reagent makes living brains transparent for deeper, non-invasive imaging
Making a living brain transparent and watching its neurons fire without disturbing their function—sounds like science fiction, doesn’t it? Yet the solution may already exist within our own bodies. In a paper published in Nature Methods, a research team led by Kyushu University introduces a new reagent called SeeDB-Live.
SeeDB-Live uses albumin—a common protein in blood serum—to clear tissue while preserving cellular function. The technique allows scientists to see deeper, brighter structures in both brain slices in a dish and living mice, achieving neural activity that was previously out of sight.
“This is the first time tissue clearing has been achieved without altering its biology,” says Takeshi Imai, professor at Kyushu University’s Faculty of Medical Sciences and the study’s senior author.
Plasma Phosphorylated Tau 217 and Incident MCI and Dementia in Older Women
In this cohort study of cognitively unimpaired older women, p-tau217 was associated with incident MCI or dementia up to 25 years later.
This cohort study examines associations of baseline plasma phosphorylated tau 217 with incident mild cognitive impairment (MCI) or dementia and whether associations vary by age, race, APOE ε4 carrier status, or hormone therapy use among older men and women.
We are not alone: Our sun escaped together with stellar ‘twins’ from galaxy center
Researchers have uncovered evidence for our sun joining a mass migration of similar “twins” leaving the core regions of our galaxy, 4 to 6 billion years ago. The team created and studied an unprecedentedly accurate catalog of stars and their properties using data from the European Space Agency’s Gaia satellite. Their discovery sheds light on the evolution of our galaxy, particularly the development of the rotating bar-like structure at its center.
While archaeology on Earth studies the human past, galactic archaeology traces the vast journey of stars and galaxies. For example, scientists know that our sun was born around 4.6 billion years ago, more than 10,000 light years closer to the center of the Milky Way than we are today.
While studies of the composition of stars support this theory, this has long proven a conundrum for scientists. Observations reveal an enormous bar-like structure at our galactic center which creates a “corotation barrier,” which makes it difficult for stars to escape so far from the center.
Secondary bile acids as immune and metabolic mediators
The human liver makes two primary bile acids that are cholesterol derivates, while, intestinal microbiota is the source of hundreds of secondary bile acids and microbially conjugated bile acids.
A dysbiotic microbiota releases altered quantities and varieties of secondary bile acids, which contribute to intestinal and systemic immune dysregulation.
In this review the authors discuss recent advances in secondary bile acids, the intestinal microbiota generating them, and their role in immune disorders. sciencenewshighlights ScienceMission https://sciencemission.com/Secondary-bile-acids
Bile acids are cholesterol derivatives, generated by the coordinated intervention of human and bacterial genes, functioning as endogenous ligands for multiple transcription factors and receptors throughout the body. While only two primary bile acids are generated by the human liver, the intestinal microbiota is the source of hundreds of secondary bile acids and microbially conjugated bile acids. Secondary bile acids regulate immune function throughout the body, promote the conversion of thyroid hormone, and regulate energy expenditure in muscle and adipose tissues, ultimately contributing to the beneficial effects of calorie restriction on human health and longevity. Here, we discuss recent advances in our understanding of secondary bile acids, the intestinal microbiota generating them, and their role in immune disorders.
Diltiazem With Blood Thinners Tied to Bleeding Risk
Among patients with atrial fibrillation (AF) who initiated apixaban or rivaroxaban, the use of diltiazem was associated with a higher risk for serious bleeding complications than the use of metoprolol. The risk for bleeding was particularly elevated in patients who received diltiazem doses exceeding 120 mg daily.
Patients with atrial fibrillation who use diltiazem combined with apixaban or rivaroxaban face an increased risk for serious bleeding events compared with those who use metoprolol.
Human brain and AI speech recognition decode speech in similar step-by-step stages, study finds
Over the past decades, computer scientists have developed numerous artificial intelligence (AI) systems that can process human speech in different languages. The extent to which these models replicate the brain processes via which humans understand spoken language, however, has not yet been clearly determined.
Researchers at Columbia University, IBM Research and the Feinstein Institutes for Medical Research recently carried out a study aimed at comparing how automatic speech recognition (ASR) systems and the human brain decode speech. Their findings, published in Nature Machine Intelligence, suggest that activity in specific brain regions while people make sense of spoken language corresponds to specific stages in the processing of speech by AI models.
“The core mystery we wanted to solve is how the human brain performs the incredible computational feat of turning raw acoustic vibrations, the sounds of speech, into discrete linguistic meaning,” Nima Mesgarani, senior author of the paper, told Tech Xplore. “We now have AI systems that match human performance in transcribing speech, but we didn’t know if they were reaching those solutions independently or if they had converged on the same strategy as our biology.”
Molecular mechanisms of insulin resistance
1. Insulin stimulates tyrosine phosphorylation of the insulin receptor and of an endogenous substrate of approximately 185 kDa (insulin receptor substrate 1 or IRS-1). IRS-1 fulfills the criteria of a direct substrate of the insulin receptor, and tyrosine phosphorylation of IRS-1 leads to another step in insulin action, i.e., an association of phosphorylated IRS-1 with the enzyme PI3-kinase activating this enzyme. Using antipeptide antibodies to insulin receptor, to IRS-1 and to PI 3-kinase together with anti-phosphotyrosine antibodies it is possible to study insulin-stimulated insulin receptor phosphorylation, IRS-1 phosphorylation and the association/activation of IRS-1/PI 3-kinase. 2. In this review we describe alterations in these three early steps of insulin action after binding in animal models of insulin resistance, i.e., streptozotocin-induced diabetes (STZ diabetes), fasting, spontaneously hypertensive rats, the ob/ob mice, dexamethasone-treated rats, and the chronic effect of insulin on Fao cells in culture. 3. In states of insulin resistance with hypoinsulinemia (STZ diabetes and fasting) there is an increase in these early steps of insulin action. In animal models of insulin resistance with hyperinsulinemia there is a decrease in these steps of insulin action, indicating molecular post-receptor defects. Since we could reproduce the decrease in these three early steps of insulin action in cells in culture by chronic treatment with insulin, we postulate that these defects may be a consequence of the hyperinsulinemia of these animals.
Targeted Remediation of the Ipsilesional Arm in Chronic Stroke: A Randomized Clinical Trial
Among patients with chronic stroke and severe contralesional impairment, targeted ipsilesional arm training supported significant and sustained improvements in ipsilesional motor performance vs best practice therapy.
Importance Ipsilesional upper-limb motor deficits after stroke are functionally important yet largely neglected in rehabilitation. Remediation may improve motor outcomes in individuals with severe contralesional arm hemiparesis.
Objective To determine whether training of the ipsilesional arm improves motor performance in chronic stroke with severe contralesional impairment and significant ipsilesional arm motor deficits.
Design, Setting, and Participants This 2-site, parallel-group randomized clinical trial with blinded outcome assessment was conducted from February 2019 to August 2024, with follow-up through 6 months posttreatment. Data analysis was performed from August 2024 through August 2025. The trial was conducted at outpatient research laboratories at Penn State College of Medicine and the University of Southern California among adults with radiologically confirmed unilateral middle cerebral artery stroke, severe contralesional upper-extremity impairment (Fugl-Meyer score ≤28), and ipsilesional motor deficits. Participants were randomly assigned with equal probability to 2 treatment groups and stratified by sex.