This Special Communication describes obstacles to sharing data and biospecimens and proposes strategies to enhance access and collaboration.
Category: biotech/medical – Page 73
Genomic reorganization at the transition to gametogenesis
Using a technique called Hi-C analysis, which looks at how DNA is arranged in three dimensions inside the nucleus, the team found that at this transitional point the genome’s three-dimensional organisation becomes less structured and chromosomes become more separated inside the nucleus.
Creating sperm and eggs in the laboratory (in vitro) remains one of the greatest challenges in reproductive biology. To study this process, scientists use primordial germ cell–like cells (PGCLCs), which are lab-generated cells derived from embryonic stem cells that mimic the embryo’s earliest reproductive cells. However, these PCGLCs often fail to complete all the steps of meiosis, making it difficult to create functional sperm and eggs in petri dishes.
After studying the process in germ cells from the embryos, the team studied lab-generated mouse PCGLCs to see if the centromeres migrated to the periphery of the nucleus in vitro too, but they did not see the same phenomenon.
“The presence of this chromosome conformation in embryonic germ cells, but not lab-grown cells, suggests that this structural change could be required for meiosis to proceed properly, and could explain why meiosis is so difficult to recreate outside the body,” says the author, “but we need to do more work to fully characterise the process before we can say for sure.”
“Our study has uncovered a previously unknown and frankly very surprising restructuring of genome architecture that occurs in developing germ cells, which we believe is critical for a successful execution of meiosis,” says the senior author. ScienceMission sciencenewshighlights.
In our cells, our DNA carries chemical or ‘epigenetic’ marks that decide how genes will be used in different tissues. Yet in the group of specialised cells, known as ‘germ cells’, which will later form sperm and eggs, these inherited chemical instructions must be erased or reshuffled so development can begin again with a fresh blueprint in future generations.
Foundation AI model uses MRI data to predict multiple brain disorders
Artificial intelligence (AI) systems are computational models that can learn to identify patterns in data, make accurate predictions or generate content (e.g., texts, images, videos or sound recordings). These models can reliably complete various tasks and are now also used to carry out research rooted in different fields.
Over the past few decades, some AI models have proved promising for the early diagnosis and study of specific diseases or neuropsychiatric conditions. For instance, by analyzing large amounts of brain scans collected using a noninvasive technique known as magnetic resonance imaging (MRI), AI could uncover patterns associated with tumors, strokes and neurodegenerative diseases, which could help to diagnose these conditions.
Researchers at Mass General Brigham, Harvard Medical School and other institutes recently developed Brain Imaging Adaptive Core (BrainIAC), a large AI system pre-trained on a vast pool of MRI data that could be adapted to tackle different tasks. This foundation model, presented in a paper published in Nature Neuroscience, was found to outperform many models that were trained to complete specific medical or neuroscience-related tasks.
Protein Folding and Quality Control in the Endoplasmic Reticulum: Recent Lessons from Yeast and Mammalian Cell Systems
The evolution of eukaryotes was accompanied by an increased need for intracellular communication and cellular specialization. Thus, a more complex collection of secreted and membrane proteins had to be synthesized, modified, and folded. The endoplasmic reticulum (ER) thereby became equipped with devoted enzymes and associated factors that both catalyze the production of secreted proteins and remove damaged proteins. A means to modify ER function to accommodate and destroy misfolded proteins also evolved. Not surprisingly, a growing number of human diseases are linked to various facets of ER function. Each of these topics will be discussed in this article, with an emphasis on recent reports in the literature that employed diverse models.
Adaptive Optimization of Vascular-Targeted Photodynamic Therapy Efficiency Based on Hyperspectral-Photoacoustic Dual-Modality Imaging Feedback
Objective: To enhance vascular-targeted photodynamic therapy (V-PDT) efficacy by integrating real-time dosimetric monitoring and adaptive irradiance modulation based on dynamic physiological feedback. Impact Statement: This study presents a closed-loop, dual-modality optical imaging-guided V-PDT platform that enables individualized, oxygen-informed irradiance control, improving therapeutic precision and efficiency. Introduction: While V-PDT is a promising, minimally invasive treatment for tumors and vascular abnormalities, its efficacy is often hindered by rapid oxygen depletion under high irradiance, leading to treatment-limiting hypoxia. Accurate, real-time assessment of both photosensitizer concentration and blood oxygenation is essential to guide optimized therapeutic strategies, yet such capability has remained elusive in clinical settings.
Abstract: In the 1960’s, megamitochondria in hepatocytes were identified in injured liver tissue
Here, Wen-Xing Ding find alterations in mitochondrial dynamics and the accumulation of large mitochondria contribute to liver tumor development in mice: https://doi.org/10.1172/JCI194441 # MASH
The EM image shows liver cells with megamitochondria (arrows) from mice lacking liver-specific dynamin-related protein 1 (Dnm1).
1Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, Kansas, USA.
2Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences and.
3Department of Pharmacology, School of Medicine, Wayne State University, Detroit, Michigan, USA.
Muscle repair may hinge on a timed metabolic ‘switch,’ study suggests
Scientists at the University of California, Irvine’s School of Pharmacy & Pharmaceutical Sciences have discovered how muscle stem cells “flip a switch” to rebuild damaged muscle—a finding that could help address muscle loss linked to aging, injury and widely used weight-loss medications.
The study, published this week in Nature Metabolism, shows that muscle recovery is not just about protein or exercise. It depends on timing and how muscle cells use fuel.
Researchers learned that immediately after stress, muscle stem cells temporarily slow down energy production. Instead of burning glucose for energy, they reroute it into protective repair processes to produce antioxidants that reduce inflammation. Once repairs are complete, energy production ramps back up and new muscle fibers form and strengthen.
Long-living wild mouse may hold secret to healthy aging
When it comes to health, some of our animal neighbors have extraordinary advantages. Ostriches, for example, are highly resistant to viruses, while sharks rarely develop cancer. And species like naked mole rats and bowhead whales live for astonishingly long periods of time, decades and centuries, respectively.
Researchers are now starting to understand why another species—the golden spiny mouse—seems to be unhindered by the negative health effects that typically accompany aging.
Reporting in Science Advances, researchers at Yale School of Medicine (YSM) have begun to uncover how this wild mouse, native to rocky deserts in the Middle East, resists physical, cognitive, and immunological decline while living six to seven times longer than other wild mice.