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Human DNA-PKcs promotes broken DNA-end structure independence during NHEJ

Whether DNA-PKcs is necessary for non-homologous end joining has been biochemically obscure. Through optimization of reaction conditions, Fujii and Modesti show that DNA-PKcs plays a constructive role, which leads to indistinguishable repair efficiencies between cohesive-end and blunt-end DNA substrates.

Abstract: Metabolic syndrome and excessive alcohol consumption lead to liver injury and fibrosis, characterized by increased collagen deposition from hepatic stellate cells

https://doi.org/10.1172/JCI197923 Here, David A. Brenner & team discover the RNA-binding protein LARP6 as a master coordinator of hepatic stellate cell activation and fibrosis, using human tissue and liver spheroid models of MASH and MetALD.

The image shows collagen labeling (red) in human liver spheroids MASH model with LARP6-targeting ASO (DAPI, blue). Collagen labeling is decreased compared with MASH control.


11 Center for Epigenomics, UCSD, La Jolla, California, USA.

12 Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA.

13 Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, Florida, USA.

Experiments advance efforts to restore vision with transplanted neurons

Researchers at Johns Hopkins Medicine say they have successfully demonstrated that disrupting an eye structure long suspected of blocking the growth and survival of transplanted nerve cells may help restore vision in people with optic nerve damage.

A report on the experiments with animals, stem cells and donated eye tissue was published in Science Translational Medicine. It suggests that altering or removing a thin layer of tissue called the internal limiting membrane, which separates the light-sensing retinal tissue at the back of the eye from the gel-like vitreous fluid that fills the eye, could help transplanted retinal ganglion cells (RGCs) survive and grow in people with blinding optic nerve damage.

Such damage, also known as optic neuropathy, occurs when retinal ganglion cells die of disease, inflammation or injury and stop carrying electrical signals to the brain. Common causes of damage include glaucoma, optic nerve inflammation (optic neuritis) and ischemic optic neuropathy (sudden loss of blood flow to the optic nerve).

Neuromodulation for gait disorders

Gait impairments such as freezing, weakness and imbalance remain resistant to standard therapies across neurological disorders. This Review examines advances in neuromodulation, from refining deep brain stimulation to integrating spinal and distributed strategies. It discusses adaptive neurotechnologies, mechanistic insights and a framework for tailoring spatiotemporally precise interventions to restore gait control.

New sensor sniffs out pneumonia on a patient’s breath

Diagnosing some diseases could be as easy as breathing into a tube. MIT engineers have developed a test to detect disease-related compounds in a patient’s breath. The new test could provide a faster way to diagnose pneumonia and other lung conditions. Rather than sit for a chest X-ray or wait hours for a lab result, a patient may one day take a breath test and get a diagnosis within minutes.

The new breath test is a portable, chip-scale sensor that traps and detects synthetic compounds, or “biomarkers,” of disease, which are initially attached to inhalable nanoparticles. The biomarkers serve as tiny tags that can only be unlocked and detached from the nanoparticle by a very particular key, such as a disease-related enzyme.

The idea is that a person would first breathe in the nanoparticles, similar to inhaling asthma medicine. If the person is healthy, the nanoparticles would eventually circulate out of the body intact. If a disease such as pneumonia is present, however, enzymes produced as a result of the infection would snip off the nanoparticles’ biomarkers. These untethered biomarkers would be exhaled and measured, confirming the presence of the disease.

Dynamic interactions between brain tumors and immune cells

Glioblastoma, the most common and most aggressive brain tumor type in adults, remains difficult to treat because it can infiltrate surrounding brain tissue and spread far beyond the main tumor. Researchers have captured this infiltration process in the living brain with advanced microscopy. Their study is based on observations in mice affected by a brain cancer very similar to human glioblastoma.

The results, published in the scientific journal Immunity, reveal complex and situation-dependent interactions between glioblastoma cells and the brain’s resident immune cells, also known as “microglia”. These cells patrol the brain in search of threats. The current findings suggest that microglia are not passive bystanders, but actively influence both the containment and the spread of the tumor.

The scientists observed these processes by means of so-called three-photon microscopy that employs infrared light. Focus was on the “far infiltration zone”, which designates a tissue region located several millimeters away from the primary tumor.

Among other things, the team discovered that the behavior of microglia changed as a tumor spread. Specifically, microglia showed increased motility and surveillance activity when only a few glioblastoma cells were present. However, as tumor infiltration intensified, this immune response declined.

Besides, the scientists investigated the effects of disabling a certain receptor that microglia use to sense their environment. The authors show that CX3CR1 deficiency enhanced microglial reactivity while limiting GB cell migration.

Furthermore, they looked into pharmacological depletion, i.e., drastically reducing the number of immune cells. Microglia depletion with the CSF1R inhibitor PLX5622 reduced GB cell migration and constrained tumor microtube ™ plasticity. ScienceMission sciencenewshighlights.

Could a natural hormone reverse obesity? New research reveals the answer

In a groundbreaking study, scientists have unlocked a major piece of the obesity puzzle, discovering that a naturally occurring hormone can reverse weight gain by targeting the same control center in the brain as popular weight-loss drugs like Ozempic and Wegovy.

The study, led by researchers at the University of Oklahoma and published in Cell Reports, highlighted the hormone FGF21 as a powerful tool in regulating metabolism and appetite.

For years, scientists assumed that weight-regulating signals primarily targeted the hypothalamus. However, Dr. Matthew Potthoff and his team were surprised to find that FGF21 actually bypasses that area, sending signals instead to the hindbrain-the lower back portion of the brain.

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