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Comment by Dr. Krishna Kumari Challa on July 21, 2023 at 2:04pm

The quirks of asp caterpillar venom support the idea it evolved independently from other insect venom, the researchers say. In fact, its origins seem to lie outside the animal kingdom entirely.

When researchers  looked at it more closely, they saw proteins that were very similar to some of the bacterial toxins that make people sick.

Specifically, asp caterpillar venom resembles a type of bacterial toxin that binds itself to the surface of a cell, the researchers explain, assembling into doughnut-like structures that rip holes in their cell target.

While organisms normally pass genes down their offspring in a so-called vertical fashion, sometimes genes can be transferred across between species – even distantly related ones – in a less common horizontal process.

Previous research has found evidence of horizontal gene transfer from bacteria to other, more complex creatures, including the transfer of genes involved with producing venom toxins.

In their new study, researchers say they've found evidence that major components of asp caterpillar venom were recruited as venom toxins from genes that bacteria transferred horizontally to their ancestors.

The venom in these caterpillars has evolved via the transfer of genes from bacteria more than 400 million years ago.

https://www.pnas.org/doi/10.1073/pnas.2305871120

Part 2

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Comment by Dr. Krishna Kumari Challa on July 21, 2023 at 2:01pm

Caterpillar Conceals a Venom Unlike Any Ever Seen in Insects

Caterpillars with a notoriously painful sting may have evolved their venom with help from ancient microbes, according to a new study  by scientists.

Their analysis has uncovered signs that a process known as horizontal gene transfer may have allowed sequences for toxins to jump from bacteria to the insect some time in their evolutionary past.

While the caterpillar's venom remains largely shrouded in mystery, researchers say its molecular secrets could turn out to be surprisingly beneficial for us.

The caterpillars wielding this venom are larvae of flannel moths (Megalopyge sp.); a soft, fuzzy genus native to North and South America. They're sometimes called "puss caterpillars," since their luxuriant coats of hairlike bristles can make them look sort of like caterpillar-sized cats.

But that's not their only nickname. Also known as "asp caterpillars," there's a hidden danger below those bristles.

The caterpillars' fur obscures an arsenal of venomous spines, which can inject powerful toxins into any would-be predators or hapless humans who touch them.

This venom causes an immediate and intense burning pain, commonly inspiring descriptions such as "being hit with a baseball bat," "walking on hot coals," or "the worst pain a patient has ever experienced," the researchers write.

part 1

Comment by Dr. Krishna Kumari Challa on July 21, 2023 at 12:02pm

A Cracked Piece of Metal Healed Itself in an Experiment!

 Scientists observed a metal healing itself, something never seen before. If this process can be fully understood and controlled, we could be at the start of a whole new era of engineering.

researchers were testing the resilience of the metal, using a specialized transmission electron microscope technique to pull the ends of the metal 200 times every second. They then observed the self-healing at ultra-small scales in a 40-nanometer-thick piece of platinum suspended in a vacuum.

Cracks caused by the kind of strain described above are known as fatigue damage: repeated stress and motion that causes microscopic breaks, eventually causing machines or structures to break. Amazingly, after about 40 minutes of observation, the crack in the platinum started to fuse back together and mend itself before starting again in a different direction.

Researchers have now confirmed  that metals have their own intrinsic, natural ability to heal themselves, at least in the case of fatigue damage at the nanoscale.

These are exact conditions, and we don't know yet exactly how this is happening or how we can use it. However, if you think about the costs and effort required for repairing everything from bridges to engines to phones, there's no telling how much difference self-healing metals could make.

And while the observation is unprecedented, it's not wholly unexpected. In 2013, materials scientists  worked on a study predicting that this kind of nanocrack healing could happen, driven by the tiny crystalline grains inside metals essentially shifting their boundaries in response to stress.

That the automatic mending process happened at room temperature is another promising aspect of the research. Metal usually requires lots of heat to shift its form, but the experiment was carried out in a vacuum; it remains to be seen whether the same process will happen in conventional metals in a typical environment.

A possible explanation involves a process known as cold welding, which occurs under ambient temperatures whenever metal surfaces come close enough together for their respective atoms to tangle together. Typically, thin layers of air or contaminants interfere with the process; in environments like the vacuum of space, pure metals can be forced close enough together to literally stick.

https://www.nature.com/articles/s41586-023-06223-0

Comment by Dr. Krishna Kumari Challa on July 21, 2023 at 10:56am

The First Dark Stars
At least three far-off objects observed by the James Webb Space Telescope (JWST) could be stellar objects called “dark stars.” These stars might not be fueled by nuclear fusion but by the self-annihilation of dark matter—the invisible stuff that is thought to make up about 85 percent of the matter in the universe. Dark stars could have formed soon after the big bang, from the collapse of helium and hydrogen clouds that annihilated the particles within.
Dark stars have never been definitively observed before–astronomers weren’t even sure they really existed. To prove these objects are indeed dark stars will take many months of observation–particularly, watching their electromagnetic spectrums for a particular isotope of helium only found in dark stars, not in galaxies.
“Finding a dark star would not only provide a new look into the early formation of the universe,” says Pearl Sandick, a theoretical particle physicist at the University of Utah, “but would also be a unique opportunity to directly observe dark matter interactions.
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In 2007, scientists proposed the idea of Dark Stars. The first phase of stellar evolution in the history of the universe may be Dark Stars (DS), powered by dark matter (DM) heating rather than by nuclear fusion. Although made almost entirely of hydrogen and helium from the Big Bang, they form at the centers of protogalaxies where there is a sufficient abundance of DM to serve as their heat source. They are very bright diffuse puffy objects and grow to be very massive. In fact, they can grow up to ten million solar masses with up to ten billion solar luminosities. In this paper, they show that the James Webb Space Telescope may have already discovered these objects.

https://www.pnas.org/doi/full/10.1073/pnas.2305762120

Comment by Dr. Krishna Kumari Challa on July 21, 2023 at 8:44am

Study shows how the brain coordinates neuronal processing and communication during sleep

Past neuroscience studies have shown that while humans are sleeping, the brain remains highly active, consolidating memories and removing toxins accumulated during waking hours. While memory consolidation during sleep is a widely documented phenomenon, the processes underpinning it are yet to be fully elucidated.

Researchers recently carried out a study investigating the neural mechanisms through which the brain facilitates neuronal processing and communication between neurons during sleep. Their paper, published in Nature Neuroscience, unveils the processes through which the sequential unfolding of specific sleep rhythms coordinates memory consolidation while humans are asleep.

A few years ago, scientists found that some of the key sleep signatures ('slow oscillations,' 'spindles' and 'ripples') coincide in the hippocampus, the brain's 'memory hub.' This was a good indication that the synchronization of these sleep rhythms may be involved in memory consolidation. What was missing, however, was evidence that they in fact impact neuronal firing rates, i.e., the 'hard currency' of learning and plasticity.

Scientists now recorded the brain activity of 10 human participants as they were asleep using a technique known as intracranial electroencephalography (iEEG). These participants were patients with epilepsy who had electrodes implanted in their brain as part of their treatment.

While the patients were sleeping, Staresina and his colleagues simultaneously recorded their sleep rhythms and neuron firing rates. The recordings they collected showed that firing rates and neural communication are indeed orchestrated by slow oscillations, spindles and ripples, as they hypothesized.

Bernhard P. Staresina et al, How coupled slow oscillations, spindles and ripples coordinate neuronal processing and communication during human sleep, Nature Neuroscience (2023). DOI: 10.1038/s41593-023-01381-w

Comment by Dr. Krishna Kumari Challa on July 20, 2023 at 12:51pm

People With Complete Color Blindness Given Their First Sight of Color
A small selection of volunteers who were completely color blind can now faintly detect a splash of color following retinal gene therapy.

Following the trial by researchers in Israel, three adults and one child who could only sense brightness of light found that after gene therapy they were able to tell a red object apart from its darker background.
Achromatopsia is caused by defects in genes that control cone cells, our eyes' color-sensors. The approximately 1 in 30,000 people affected see all the vibrant colors of the world as blurry shades of gray.

A single gene mutation caused the congenital condition in the volunteers, and the researchers hoped that inserting functional copies of the gene into cone cells would allow them to see color.
The researchers used a viral vector to transport a functional copy of the gene into the retina which houses cone cells, in one of each participant's eyes.
Researchers found treated 'achromats' can perceive red color, albeit in a very limited way, and differently than normally sighted controls.
But the different shades of gray were not replaced by a range of rainbow colors.

Nevertheless, color detection was evident in all patients' treated eyes.

https://www.cell.com/current-biology/fulltext/S0960-9822(23)00826-6?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0960982223008266%3Fshowall%3Dtrue

Comment by Dr. Krishna Kumari Challa on July 20, 2023 at 12:03pm

Lasting Brain Effects
Researchers recently examined the brains of patients born with congenital blindness who had their vision restored surgically. Despite many years of having their sight back, these individuals had a visual cortex that more closely resembled the corresponding visual areas of individuals with permanent blindness.

Why this matters: These findings suggest that harsh experiences or environments early in life can result in irreversible structural changes in multiple regions of the brain. Poverty and adversity (abuse or neglect) have often been found to have a widespread effect across the brain, and extrapolating from this vision study, experts expect permanent neurological changes resulting from harsh early experiences, write Cordula Hölig, Brigitte Röder and Ramesh Kekunnaya, cognitive neuroscientists and an ophthalmologist, respectively, who are the study’s lead authors.

What the experts say: “Poverty and adversity can cause changes in brain development. …Ensuring access to safe environments, affordable health care, healthy food and appropriate education gives children the opportunity to develop and stay physically and mentally healthy,” write the study authors.

Comment by Dr. Krishna Kumari Challa on July 20, 2023 at 12:02pm

The true cost of science’s language barrier
Researchers whose first language is not English can spend around twice as long reading an English-language scientific journal article as native speakers. In a survey of more than 900 environmental scientists from 8 countries, non-native speakers also reported needing more time to prepare conference presentations in English — and many avoid this type of commitment. Conservation scientist and co-author Tatsuya Amano has felt the impact first-hand as a Japanese researcher who has adapted to working in the United Kingdom and Australia. “Behind the scenes, I have to spend so much time to reach that level.”

https://journals.plos.org/plosbiology/article?id=10.1371/journal.pb...

https://www.nature.com/articles/d41586-023-02320-2?utm_source=Natur...

Comment by Dr. Krishna Kumari Challa on July 20, 2023 at 11:59am

Can India's new billion-dollar funding agency boost research?

India’s proposed National Research Foundation will shake up the scientific landscape to encourage a culture of research.

India is planning to set up a national agency to increase research across the nation’s thousands of universities, colleges, institutes and laboratories. Legislation to establish the fund is expected to be introduced into the Indian Parliament in the next three weeks.

The National Research Foundation (NRF) will have a budget of roughly US$6 billion over five years. Some 70% of these funds is intended to come from investors in the private sector, and the remaining portion will be covered by the government.

The NRF’s goal is to “seed, grow and promote” research across the country’s institutions by strengthening ties between academia, industry and the government, according to a statement from the Ministry of Science and Technology.

https://www.nature.com/articles/d41586-023-02336-8?utm_source=Natur...

Comment by Dr. Krishna Kumari Challa on July 20, 2023 at 11:51am

Bacterial protein found in the urogenital tract may contribute to reduced fertility, birth defects

A   study, published on July 17 in the Proceedings of the National Academy of Sciences (PNAS), established a new link between genomic instability and a protein from Mycoplasma fermentans, a kind of bacterium that commonly colonizes the urogenital tract. This bacterial protein also reduced fertility in mother mice and resulted in more birth defects in their newborn pups.

The study results not only broaden our understanding of the interplay between the urogenital tract microbiota and human reproductive health, but also shed light on the previously unidentified contribution of the human microbiota to genetic abnormalities.

For this latest study, researchers created mice that make the DnaK protein normally produced by the bacterium Mycoplasma fermentans. These mice with exposure to DnaK accrued genomic instability in which entire sections of the genome were duplicated or deleted, resulting in mice with varying numbers of copies of certain genes.

The team noticed that some of these mice from three to five weeks of age had problems with movement and coordination. They found that these mice have a deletion in the Grid2 gene, which in humans leads to the rare genetic disease known as spinocerebellar ataxia-18 (SCAR18) that causes delayed development of skilled movements and intellectual disabilities.

Remarkably, this instance marks the first time a mouse model successfully recapitulated a human genetic disease de novo, showcasing this model's potential for further cancer biology research.

More than a third of the female mice that made the DnaK protein were unable to get pregnant. Additionally, more than 20% of the pups born from moms with the DnaK protein had some sort of birth defect/deformity.

"The occurrences of genomic instability, in the form of increased number of copy number variations, could explain the decreased fertility and the increased instances of abnormally developed fetuses we observed upon DnaK exposure.

https://www.pnas.org/doi/10.1073/pnas.2219897120

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