Csmsdust

Gene Mutation Leading to Autism Found to Overstimulate Brain Cells

Scientists looking to understand the fundamental brain mechanisms of autism spectrum disorder have found that a gene mutation known to be associated with the disorder causes an overstimulation of brain cells far greater than that seen in neuronal cells without the mutation.

The Rutgers-led study, spanning seven years, employed some of the most advanced approaches available in the scientific toolbox, including growing human brain cells from stem cells and transplanting them into mouse brains.

The work illustrates the potential of a new approach to studying brain disorders, scientists said.

Describing the study in the journal, Molecular Psychiatry, researchers reported that a mutation – R451C, in the gene Neurologin-3, known to cause autism in humans – was found to provoke a higher level of communication among a network of transplanted human brain cells in mouse brains. This overexcitation, quantified in experiments by the scientists, manifests itself as a burst of electrical activity more than double the level seen in brain cells without the mutation.

“We were surprised to find an enhancement, not a deficit,” said Zhiping Pang, an associate professor in the Department of Neuroscience and Cell Biology in the Child Health Institute of New Jersey at Rutgers Robert Wood Johnson Medical School and the senior author on the study. “This gain-of-function in those specific cells, revealed by our study, causes an imbalance among the brain’s neuronal network, disrupting the normal information flow.”

The interconnected mesh of cells that constitutes the human brain contains specialized “excitatory” cells that stimulate electrical activity, balanced by “inhibitory” brain cells that curtail electrical pulses, Pang said. The scientists found the oversized burst of electrical activity caused by the mutation threw the mouse brains out of kilter.

Autism spectrum disorder is a developmental disability caused by differences in the brain. About 1 in 44 children have been identified with the disorder, according to estimates from the Centers for Disease Control and Prevention.

Studies suggest autism could be a result of disruptions in normal brain growth very early in development, according to the National Institutes of Health’s (NIH) National Institute of Neurological Disorders and Stroke. These disruptions may be the result of mutations in genes that control brain development and regulate how brain cells communicate with each other, according to the NIH.

“So much of the underlying mechanisms in autism are unknown, which hinders the development of effective therapeutics,” Pang said. “Using human neurons generated from human stem cells as a model system, we wanted to understand how and why a specific mutation causes autism in humans.”

Researchers employed CRISPR technology to alter the human stem cells’ genetic material to create a line of cells containing the mutation they wanted to study, and then derived human neuron cells carrying this mutation. CRISPR, an acronym for clustered regularly interspaced short palindromic repeats, is a unique gene-editing technology.

In the study, the human neuron cells that were generated, half with the mutation, half without, were then implanted in the brains of mice. From there, researchers measured and compared the electrical activity of specific neurons employing electrophysiology, a branch of physiology that studies the electrical properties of biological cells. Voltage changes or electrical current can be quantified on a variety of scales, depending on the dimensions of the object of study.

“Our findings suggest that the Neurologin-3 R451C mutation dramatically impacts excitatory synaptic transmission in human neurons, thereby triggering changes in overall network properties that may be related to mental disorders,” Pang said. “We view this as very important information for the field.”

Pang said he expects many of the techniques developed to conduct this experiment to be used in future scientific investigations into the basis of other brain disorders, such as schizophrenia.

“This study highlights the potential of using human neurons as a model system to study mental disorders and develop novel therapeutics,” he said.

Eukaryotic cell gang!! We love women in STEM.

The organelles of the cells have been translated into human anatomy, so the nucleus is the brain, the vacuole function as the lungs, and the mitochondria is the heart since it’s the… you already know, I don’t have to say it ;)

“The time available for her to submit grants and write papers decreased sharply in the year and a half after she first became a mother. And her lower productivity continued after she had two more sons, but there often wasn’t a way to explain that on her grant applications.”

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https://www.nature.com/articles/d41586-023-00252-5

I also have a hard time explaining in my grant applications my PhD period. Even though it took 6 years to finish my PhD, I actually was much faster than average. I was on full maternity leaves not working at all for 2 years (!!) and the rest I worked part time. I managed to get my PhD in total of 3 years and 2 months of full time work equivalent.

I am glad people start noticing this and Nature writes about this issue. Let’s not punish researchers for having kids!

(via miss-biophys)

Cosmic clouds form fantastic shapes in the central regions of emission nebula IC 1805. The clouds are sculpted by stellar winds and radiation from massive hot stars in the nebula's newborn star cluster, Melotte 15. IC 1805 is located about 7,500 light years away toward the boastful constellation Cassiopeia.

Image Credit: Richard McInnis

9.9.2024.

Philosophy of science - Wikipedia

en.m.wikipedia.org

Philosophy of science - Wikipedia

Feeling like a pro in Atomic Force Microscopy

...to be honest I probably should really tell myself that at this point I really am the professional in this method. After 4 years of working with 2 different atomic force microscopes, now I started with a 3rd one, again a new type from a different company.

Only after 2 hours of training on the new machine, I could observe membranes of resistant bacteria all by myself. The membranes are the yellow pancakes sitting flat on the dark support. They are less than 8 nm high (0.000000008 m), as is visible in the blue and red profile lines. So it's super tricky to actually see them. Atomic force microscope touches the surface of my membranes and surrounding support with a tiny tip like with a finger and reconstructs the surface topology. On top of the small size, the cellular membranes are super soft so also the touching finger must be super soft to see them without damaging them.

Trying to do research on time

Physicists; uh yeah, space and time are one but we don't really know what they are actually, we use this highly specific magic crystal tho here have it

Neuroscientists: yeah, we also use the same crystal, but it doesn't matter because you don't experience time like that, we don't know

Some guy in 19th century, yeah time is not internally generated it is out there and you get it from the outside?? And then the idea took over the Europe

?? ? ?

Some neuroscientist: time doesn't exist, it's all happening at once, you brain is a time machine (the title of the book actually , one of my favorite)

Some other physicist: you're right, time doesn't exist in physics it's the humans that order things

?

Gravity?

What are we looking at?

Impulse, instinct or intuition, Applied psychology, geometry and astronomy, 1919