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Comment by Dr. Krishna Kumari Challa on May 26, 2022 at 2:13pm

Scientists detect deadly arrhythmia trifecta: Salt, swelling, and leaky sodium channels

Less than 1 percent of the population has been diagnosed with Long QT syndrome – a rare heart condition that can cause chaotic, sometimes fatal, heart rhythms.

Now, researchers  have identified two core factors that may put patients with Long QT syndrome Type 3 at significantly higher risk of sudden cardiac death. Their findings were recently published in the American Journal of Physiology – Heart and Circulatory Physiology.

Some Long QT syndrome patients are born with the disease, while others develop it as a result of natural aging, certain medications, tissue swelling, or heart disease.

The syndrome remodels the heart’s sodium channels to become hyperactive and leaky, which disrupts the heart’s normal electrical pathways. Long QT is diagnosed when the length of time it takes for a heartbeat to drop from its peak to baseline, the QT interval, is extended on an electrocardiogram reading.

Some patients with Long QT live long, healthy, and event-free lives, while others suddenly die. Some Long QT syndrome patients are born with the disease, while others develop it as a result of natural aging, certain medications, tissue swelling, or heart disease.

The syndrome remodels the heart’s sodium channels to become hyperactive and leaky, which disrupts the heart’s normal electrical pathways. Long QT is diagnosed when the length of time it takes for a heartbeat to drop from its peak to baseline, the QT interval, is extended on an electrocardiogram reading.

Some patients with Long QT live long, healthy, and event-free lives, while others suddenly die. 

This research  data suggests that the combination of tissue edema, elevated blood sodium, and faulty sodium channels trigger deadly heart arrhythmias. While Long QT is a rare disorder, anyone could acquire similar sodium channel dysfunction with age, ischemia, or other heart disease.

https://pubmed.ncbi.nlm.nih.gov/34623182/

https://vtx.vt.edu/articles/2022/05/scientists-detect-deadly-arrhyt...

Comment by Dr. Krishna Kumari Challa on May 26, 2022 at 1:58pm

A similar process is at work all over the universe. However, in stars and galaxies and in the space between them, the electrically conducting fluid is not molten metal, but plasma—a state of matter that exists at extremely high temperatures where the electrons are ripped away from their atoms. On Earth, plasmas can be seen in lightning or neon lights. In such a medium, the dynamo effect can amplify an existing magnetic field, provided it starts at some minimal level.

Where does this seed field come from? Present studies developed the underlying theory and performed numerical simulations on powerful supercomputers that show how the seed field can be produced and what fundamental processes are at work. An important aspect of the plasma that exists between stars and galaxies is that it is extraordinarily diffuse—typically about one particle per cubic meter. That is a very different situation from the interior of stars, where the particle density is about 30 orders of magnitude higher. The low densities mean that the particles in cosmological plasmas never collide, which has important effects on their behavior that had to be included in the model that these researchers were developing.

Calculations performed by the MIT researchers followed the dynamics in these plasmas, which developed from well-ordered waves but became turbulent as the amplitude grew and the interactions became strongly nonlinear. By including detailed effects of the plasma dynamics at small scales on macroscopic astrophysical processes, they demonstrated that the first magnetic fields can be spontaneously produced through generic large-scale motions as simple as sheared flows. Just like the terrestrial examples, mechanical energy was converted into magnetic energy.

An important output of their computation was the amplitude of the expected spontaneously generated magnetic field. What this showed was that the field amplitude could rise from zero to a level where the plasma is "magnetized"—that is, where the plasma dynamics are strongly affected by the presence of the field. At this point, the traditional dynamo mechanism can take over and raise the fields to the levels that are observed. Thus, their work represents a self-consistent model for the generation of magnetic fields at cosmological scale.

Muni Zhou et al, Spontaneous magnetization of collisionless plasma, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2119831119

Part 3

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Comment by Dr. Krishna Kumari Challa on May 26, 2022 at 1:55pm

Scientists started thinking about this problem by considering the way that electric and magnetic fields were produced in the laboratory. When conductors, like copper wire, move in magnetic fields, electric fields are created. These fields, or voltages, can then drive electrical currents. This is how the electricity that we use every day is produced. Through this process of induction, large generators or "dynamos" convert mechanical energy into the electromagnetic energy that powers our homes and offices. A key feature of dynamos is that they need magnetic fields in order to work.

But out in the universe, there are no obvious wires or big steel structures, so how do the fields arise? Progress on this problem began about a century ago as scientists pondered the source of the Earth's magnetic field. By then, studies of the propagation of seismic waves showed that much of the Earth, below the cooler surface layers of the mantle, was liquid, and that there was a core composed of molten nickel and iron. Researchers theorized that the convective motion of this hot, electrically conductive liquid and the rotation of the Earth combined in some way to generate the Earth's field.

Eventually, models emerged that showed how the convective motion could amplify an existing field. This is an example of "self-organization"—a feature often seen in complex dynamical systems—where large-scale structures grow spontaneously from small-scale dynamics. But just like in a power station, you needed a magnetic field to make a magnetic field.

part 2

Comment by Dr. Krishna Kumari Challa on May 26, 2022 at 1:54pm

How the universe got its magnetic field

When we look out into space, all of the astrophysical objects that we see are embedded in magnetic fields. This is true not only in the neighborhood of stars and planets, but also in the deep space between galaxies and galactic clusters. These fields are weak—typically much weaker than those of a refrigerator magnet—but they are dynamically significant in the sense that they have profound effects on the dynamics of the universe. Despite decades of intense interest and research, the origin of these cosmic magnetic fields remains one of the most profound mysteries in cosmology.

In previous research, scientists came to understand how turbulence, the churning motion common to fluids of all types, could amplify preexisting magnetic fields through the so-called dynamo process. But this remarkable discovery just pushed the mystery one step deeper. If a turbulent dynamo could only amplify an existing field, where did the "seed" magnetic field come from in the first place?

We wouldn't have a complete and self-consistent answer to the origin of astrophysical magnetic fields until we understood how the seed fields arose. New work carried out recently provides an answer that shows the basic processes that generate a field from a completely unmagnetized state to the point where it is strong enough for the dynamo mechanism to take over and amplify the field to the magnitudes that we observe.

Naturally occurring magnetic fields are seen everywhere in the universe. They were first observed on Earth thousands of years ago, through their interaction with magnetized minerals like lodestone, and used for navigation long before people had any understanding of their nature or origin. Magnetism on the sun was discovered at the beginning of the 20th century by its effects on the spectrum of light that the sun emitted. Since then, more powerful telescopes looking deep into space found that the fields were ubiquitous.

And while scientists had long learned how to make and use permanent magnets and electromagnets, which had all sorts of practical applications, the natural origins of magnetic fields in the universe remained a mystery. Recent work has provided part of the answer, but many aspects of this question are still under debate.

Part 1

Comment by Dr. Krishna Kumari Challa on May 26, 2022 at 1:41pm

None of the tissue samples exhibited changes in epigenetic aging. But the researchers did find changes to the way the cells handled energy—their ability to sense nutrients was impacted. This ability plays a major role in cell growth, reproduction and death. The researchers also found changes in mitochondrial activity and in the number of stem cells in their samples. They suggest that epigenetic aging does not predict changes in senescence, nor does it match with age-related changes to telomeres, one of the major indicators of aging in general.

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Epigenetic aging clock predicts the biological age of individual cells

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More information: Sylwia Kabacik et al, The relationship between epigenetic age and the hallmarks of ageing in human cells, Nature Aging (2022). DOI: 10.1038/s43587-022-00220-0

Steve Horvath et al, DNA methylation clocks for dogs and humans, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2120887119

Part 2

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Comment by Dr. Krishna Kumari Challa on May 26, 2022 at 1:40pm

Investigating whether epigenetic aging is the manifestation of one or more aging hallmarks

A team of researchers affiliated with a host of institutions in the U.K. and the U.S. has conducted an investigation into whether epigenetic aging is the manifestation of one or more aging hallmarks. In their paper published in the journal Nature Aging, the group describes subjecting human cells to three kinds of abuse and then testing them to see if the cells aged epigenetically.

Over the past several years, some researchers focusing on the science of aging have become proponents of what is described as epigenetic aging, whereby certain attributes of our bodies age at a rate that may not be consistent with our biological age. That has led to studies aimed at measuring the epigenetic age of people (and other animals) using DNA methylation clocks, ostensibly as a means to circumvent them and allow people to live longer. In this new effort, the researchers studied hallmarks of aging such as exposure to radiation, reproduced them and tested the effects on the pace of epigenetic aging.

The work involved collecting tissue samples from 14 healthy people and dividing them into four groups. One group was subjected to a small dose of radiation, another had some of their cell properties altered to become cancerous, and yet another set was subjected to induced senescence. The fourth group was left undisturbed. Each of the groups represented a hallmark of aging. Exposure to radiation can, for example, make changes to the genome that results in accelerated aging.

Part 1

Comment by Dr. Krishna Kumari Challa on May 25, 2022 at 7:01am

Scientists discover new tools to fight potentially deadly protozoa

Comment by Dr. Krishna Kumari Challa on May 25, 2022 at 6:52am

A candlelight-like glow from a flexible organic LED

Giving off a comfortable glow, candles set the ambiance for a special dinner or just a quiet evening at home. However, some lighting alternatives, such as electronic candles, give off unwanted blue wavelengths that interfere with the body's circadian rhythm. Now, researchers reporting in ACS Applied Electronic Materials have fabricated an improved bendable organic LED that releases candlelight-like light for flexible lighting and smart displays that people can comfortably use at night.

researchers developed organic LEDs that released warm-white light, similar to that produced by candles. However, the devices still emitted some blue wavelength light, which can interfere with sleep because it dampens the body's production of melatonin. These devices were made of solid materials and weren't flexible.

One option for making them bendable is to use a plastic backing, as has been done for other organic LEDs. But plastics don't stand up well to repeated bending. Another option for the backing is mica—a natural mineral with extreme temperature tolerance that can be split into bendable, transparent sheets. So, Jou, Ying-Hao Chu and colleagues wanted to develop an even better organic LED and apply it to a mica backing, creating a bendable candle-like light with a long lifespan.

The researchers deposited a clear indium tin oxide film onto a transparent mica sheet as the LED's anode, which could bend 50,000 times without breaking. Next, the team mixed the luminescent substance N,N'-dicarbazole-1,1'-biphenyl with red and yellow phosphorescent dyes to produce a light-emitting layer. This layer was then placed between electrically conductive solutions with the anode on one side and an aluminum layer on the other side, creating a flexible organic LED.

When a constant current was applied to the device, it produced a bright, warm light with even less blue wavelength emissions than natural candlelight. Calculations showed that exposure to the LED for 1.5 hours would suppress a person's melatonin production by about 1.6%, whereas light from a cold-white compact fluorescent lamp would suppress melatonin production by 29%. The researchers say that the flexibility of their candlelight-like organic LED opens up the design opportunities for blue-light-free nighttime devices.

Tun-Hao Chen et al, Flexible Candlelight Organic LED on Mica, ACS Applied Electronic Materials (2022). DOI: 10.1021/acsaelm.2c00123

Comment by Dr. Krishna Kumari Challa on May 24, 2022 at 12:14pm

First Patient Injected With Experimental Cancer-Killing Virus in New Clinical Trial

An experimental cancer-killing virus has been administered to a human patient for the first time, with hopes the testing will ultimately reveal evidence of a new means of successfully fighting cancer tumors in people's bodies.

The drug candidate, called CF33-hNIS (aka Vaxinia), is what's called an oncolytic virus, a genetically modified virus designed to selectively infect and kill cancer cells while sparing healthy ones. In the case of CF33-hNIS, the modified pox virus works by entering cells and duplicating itself. Eventually, the infected cell bursts, releasing thousands of new virus particles that act as antigens, stimulating the immune system to attack nearby cancer cells. Previous research in animal models has shown the drug can harness the immune system in this way to hunt and destroy cancer cells, but up until now no testing has been done in humans. That's just changed, with co-developers of the drug – the City of Hope cancer care and research center in Los Angeles, and Australia-based biotech company Imugene – now announcing that the first clinical trial in human patients is underway.

https://clinicaltrials.gov/ct2/show/NCT05346484

https://www.sciencealert.com/first-patient-injected-with-experiment...

Comment by Dr. Krishna Kumari Challa on May 24, 2022 at 7:14am

Nuclear pasta, the hardest known substance in the universe

A team of scientists has calculated the strength of the material deep inside the crust of neutron stars and found it to be the strongest known material in the universe.

Neutron stars are born after supernovas, an implosion that compresses an object the size of the sun to about the size of Montreal, making them "a hundred trillion times denser than anything on earth." Their immense gravity makes their outer layers freeze solid, making them similar to earth with a thin crust enveloping a liquid core.

This high density causes the material that makes up a neutron star, known as nuclear pasta, to have a unique structure. Below the crust, competing forces between the protons and neutrons cause them to assemble into shapes such as long cylinders or flat planes, which are known in the literature as 'lasagna' and 'spaghetti,' hence the name 'nuclear pasta.' Together, the enormous densities and strange shapes make nuclear pasta incredibly stiff.

Thanks to their computer simulations, which required 2 million hours worth of processor time or the equivalent of 250 years on a laptop with a single good GPU, Caplan and his colleagues were able to stretch and deform the material deep in the crust of neutron stars.

M. E. Caplan, A. S. Schneider, C. J. Horowitz. The Elasticity of Nuclear Pasta. Physical Review Letters, 2018 [abstract]

https://www.sciencedaily.com/releases/2018/09/180918110836.htm#:~:t....

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