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Comment by Dr. Krishna Kumari Challa on June 12, 2023 at 10:36am

Octopuses Can Rewire Their 'Brains' by Editing Their Own RNA on The Fly

Octopuses have found an incredible way to protect the more delicate features of their nervous system against radically changing temperatures.

When conditions fluctuate, they can rapidly recode key proteins in their nerve cells, ensuring critical neurological activities remain functional when temperatures drop dramatically.

How do they do it? By deploying a rare superpower – editing their RNA on the fly, an ability found in some species of octopuses, squids and cuttlefish.

It's an unusual strategy, but it appears to be an effective one, and scientists think that it may be widely adopted throughout the world of cephalopods.

We generally think that our genetic information is fixed, but the environment can influence how you encode proteins, and in cephalopods this happens on a massive scale.

RNA recoding gives organisms the option to express a diverse quiver of proteins when and where they choose. In cephalopods, most of the recoding is for proteins that are really important for nervous system function, so the natural question is, are they using this to acclimate to changes in their physical environment?"

Part 1

Comment by Dr. Krishna Kumari Challa on June 12, 2023 at 10:30am

Why you can’t eat or drink before a general anaesthetic

When you have a general anaesthetic, you will usually be asked not to have anything to eat or drink for a period of time before. Although you might get annoyed, this is for your won safety. 

When the general anaesthetic is used, your body’s reflexes are temporarily stopped. If your stomach has any food and drink in it, there’s a risk of vomiting or bringing up food into your throat. If this happens, the food could get into your lungs and affect your breathing, as well as causing damage. Inhaling vomited stomach contents into your lungs is called ‘aspiration’, and it can lead to a dangerous infection.

The amount of time you have to go without food or drink before you have your operation will depend on the type of operation you’re having. However, it is usually at least six hours for food, and two hours for fluids. You’ll be told how long you must not eat or drink before your operation.

Unfortunately, even chewing gum – including nicotine gum – should be avoided during this fasting period, and soups and sweets should also not be consumed. You may also be advised to avoid certain types of fluids, such as milk, or tea and coffee with milk added to them. Clear fluids, such as water, are usually allowed until two hours before.

While it might feel annoying to avoid food, you must follow the guidelines. If you eat or drink before your surgery, your operation can be postponed or even cancelled because of the risks involved.

Comment by Dr. Krishna Kumari Challa on June 12, 2023 at 9:40am

Researchers discover that COVID-19 can cause brain cells to fuse

Researchers have discovered viruses such as SARS-CoV-2 can cause brain cells to fuse, initiating malfunctions that lead to chronic neurological symptoms. They have explored how viruses alter the function of the nervous system. Their research is published in Science Advances.

SARS-CoV-2, the virus that causes COVID-19, has been detected in the brains of people with "long COVID" months after their initial infection.

It's discovered now that COVID-19 causes neurons to undergo a cell fusion process, which has not been seen before.

Once fusion takes place, each switch either turns on both the kitchen and bathroom lights at the same time, or neither of them.  It's bad news for the two independent circuits.

The discovery offers a potential explanation for persistent neurological effects after a viral infection. In the current understanding of what happens when a virus enters the brain, there are two outcomes—either cell death or inflammation. But this new work has shown a third possible outcome, which is neuronal fusion.

Numerous viruses cause cell fusion in other tissues, but also infect the nervous system and could be causing the same problem there.

These viruses include HIV, rabies, Japanese encephalitis, measles, herpes simplex virus and Zika virus. This  research reveals a new mechanism for the neurological events that happen during a viral infection. This is potentially a major cause of neurological diseases and clinical symptoms that is still unexplored.

Ramón Martínez-Mármol et al, SARS-CoV-2 infection and viral fusogens cause neuronal and glial fusion that compromises neuronal activity., Science Advances (2023). DOI: 10.1126/sciadv.adg2248. www.science.org/doi/10.1126/sciadv.adg2248

Comment by Dr. Krishna Kumari Challa on June 11, 2023 at 1:05pm

 Amorphous Ice

Comment by Dr. Krishna Kumari Challa on June 10, 2023 at 1:13pm

Millions wasted on reformatting papers

Scientists are spending millions of dollars’ worth of time reformatting rejected papers for submission to alternative journals. An analysis shows that, in 2021, the global price tag on all of tha... — just for biomedical journals. If current journal practices don’t change, the authors estimate that reformatting could cost about $2.5 billion between 2022 and 2030. Suggested remedies include universal journal guidelines, free-format submissions or a ‘golden middle’ solution that allows researchers to submit manuscripts that abide by minimal structural requirements, such as total word count. “The current system is not sustainable,” says study co-author Tibor Varga.

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Why didn't the Big Bang collapse in a giant black hole?

Despite the enormous densities, the early universe didn't collapse into a black hole because, simply put, there was nothing to collapse into.

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Limiting global warming to 2C is not enough—why the world must keep...

The Paris Climate agreement represented a historic step towards a safer future for humanity on Earth when it was adopted in 2015. The agreement strove to keep global heating below 2℃ above pre-industrial levels with the aim of limiting the increase to 1.5℃ if possible. It was signed by 196 parties around the world, representing the overwhelming majority of humanity.

Comment by Dr. Krishna Kumari Challa on June 10, 2023 at 10:52am

What Dreams May Mean
Dreams can be bizarre and disturbing, and even sometimes frightening. Do some betray a pathology? Dreams alone are not enough to diagnose a mental illness. But some characteristics of a dream may hint at disorders: for example, the frequency of nightmares is generally higher in people with a mental disorder, whether depression, anxiety or post-traumatic stress disorder (they’re particularly indicative of a person’s risk for suicide).

Why this is cool: Dreams may serve to integrate memories and lessen negative emotions around difficult life experiences; in fact, people tend to wake up happier than when they went to sleep (what I’m hearing: more naps, because SCIENCE). Those systems can get derailed in people with depression or PTSD.

What the experts say: Dreams can be useful in diagnosing some brain disorders, like differentiating between Alzheimer's and Lewy body dementia. Both involve cognitive loss, but the latter is accompanied by REM sleep behavior disorder, where the dreamer tries to physically act out what’s happening in their dream.

https://www.scientificamerican.com/article/how-dreams-reveal-brain-...

Comment by Dr. Krishna Kumari Challa on June 10, 2023 at 8:10am

At rest, the expired air of older subjects (60-76) contained an average respiratory aerosol particle concentration of 310 particles/L compared to 105 particles/L in younger subjects. The study found differences between elderly men and women, with elderly men emitting 210 particles/L compared to elderly women at 500 particles/L. While the elderly women had more than twice the particle load per liter of air, the elderly men ventilated 57% more volume than elderly women making the overall difference insignificant.

The difference was more significant during exercise as the young group averaged 620 particles/L while the elderly group reached an average of 2,090 particles/L.

While age significantly affected aerosol particle emission, sex and body mass index differences were not significant. The study highlights that one size may not fit all when planning mitigation measures, especially for indoor fitness facilities or elder care facilities during heightened infection waves or future pandemics.

 Benedikt Schumm et al, Lung aerosol particle emission increases with age at rest and during exercise, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2301145120

Part 2

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Comment by Dr. Krishna Kumari Challa on June 10, 2023 at 8:10am

Older folks found to foist more moist particles into the air

Research led by the Department of Aerospace Engineering, Institute of Fluid Mechanics and Aerodynamics, Universität der Bundeswehr München, Germany, has found unexpectedly high aerosolized respiratory particle emissions from people over 60 years old.

In their paper, "Lung aerosol particle emission increases with age at rest and during exercise," published in PNAS, the researchers detail their findings after testing 80 individuals with a recently improved method of measuring respiratory aerosol particle emission.

Airborne respiratory diseases are transmitted via viruses in respiratory aerosol particles. When a person breathes out, a high-speed stream of air rushes over the surface of the wet lining of the respiratory tract, and some of this moisture is aerosolized and carried out with the exhale. Particles within the lining hitch a ride on the exiting moisture containing a mix of salts, proteins, mucus, and potential pathogens of bacteria and viruses.

Typically the emission of aerosol particles can increase by more than 100-fold from rest to peak exercise, and with the increase, the risk of infection can rise by more than 10-fold. While testing their improved measuring method, the researchers found another significant parameter affecting the amount of particle spread—age.

Subjects aged 60 to 76 years old emitted over twice as many aerosol particles at rest and during exercise and five times as much aerosol volume. This suggests that aerosol particle emission increases when the respiratory system ages.

Part 1

Comment by Dr. Krishna Kumari Challa on June 9, 2023 at 11:23am

Researchers discover a new way to develop drugs without side effects

Have you ever wondered how drugs reach their targets and achieve their function within our bodies? If a drug molecule or a ligand is a message, an inbox is typically a receptor in the cell membrane. One such receptor involved in relaying molecular signals is a G protein-coupled receptor (GPCR). About one-third of existing drugs work by controlling the activation of this protein. Researchers now reveal a new way of activating GPCR by triggering shape changes in the intracellular region of the receptor. This new process can help researchers design drugs with fewer or no side effects.

If the cell membrane is like an Oreo cookie sandwich, GPCR is like a snake with seven segments traversing in and out of the cookie sandwich surface. The extracellular loops are the inbox for messages. When a message molecule binds to the extracellular side of the receptor, it triggers a shape change activating G proteins and the ß-arrestin protein attached to the intracellular side of the receptor. Like a molecular relay, the information passes downstream and affects various bodily processes. That is how we see, smell, and taste, which are sensations of light, smell, and taste messages.

Adverse side effects ensue if drugs acting on GPCRs activate multiple signaling pathways rather than a specific target pathway. That is why drug development focuses on activating specific molecular signal pathways within cells. Activating the GPCR from inside the cell rather than outside the cell could be one way to achieve specificity. But until now, there was no evidence of direct activation of only the intracellular side of GPCRs without the initiations from the extracellular side.

A team of researchers discovered a new receptor activation mode of a bone metabolism-related GPCR called human parathyroid hormone type 1 receptor (PTH1R) without signal transduction from the extracellular side.

Kazuhiro Kobayashi et al, Class B1 GPCR activation by an intracellular agonist, Nature (2023). DOI: 10.1038/s41586-023-06169-3

Comment by Dr. Krishna Kumari Challa on June 9, 2023 at 11:18am

Scientists develop artificial molecules that behave like real ones

Scientists  have developed synthetic molecules that resemble real organic molecules. A collaboration of researchers can now simulate the behaviour of real molecules by using artificial molecules. In this way, they can tweak properties of molecules in ways that are normally difficult or unrealistic, and they can understand much better how molecules change.

Researchers developed a system in which they can trap electrons. Electrons surround a molecule like a cloud, and they used those trapped electrons to build an artificial molecule. The results the team found were astonishing.  "The resemblance between what they built and real molecules was uncanny."

Using this simulator, the researchers created an artificial version of one of the basic organic molecules in chemistry, benzene. Benzene is the first component for a number of chemicals, like styrene, which is used to make polystyrene. By making benzene, they simulated a textbook organic molecule, and built a molecule that is made up of elements that are not organic. In addition, the molecules are 10 times bigger than their real counterparts, which makes them easier to work with.

E. Sierda et al, Quantum simulator to emulate lower-dimensional molecular structure, Science (2023). DOI: 10.1126/science.adf2685. www.science.org/doi/10.1126/science.adf2685

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