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Comment by Dr. Krishna Kumari Challa on April 5, 2024 at 9:25am

Scientists identify rare gene variants which confer up to 6-fold increase in risk of obesity

A study led by Medical Research Council (MRC) researchers has identified genetic variants in two genes that have some of the largest impacts on obesity risk discovered to date.

The discovery of rare variants in the genes BSN and APBA1 are some of the first obesity-related genes identified for which the increased risk of obesity is not observed until adulthood.

The researchers used UK Biobank and other data to perform whole exome sequencing of body mass index (BMI) in over 500,000 individuals.

They found that genetic variants in the gene BSN, also known as Bassoon, can raise the risk of obesity as much as six times and was also associated with an increased risk of non-alcoholic fatty liver disease and of type 2 diabetes.

The Bassoon gene variants were found to affect 1 in 6,500 adults.

Previous research has identified several obesity-associated gene variants conferring large effects from childhood, acting through the leptin-melanocortin pathway in the brain, which plays a key role in appetite regulation.

However, while both BSN and APBA1 encode proteins found in the brain, they are not currently known to be involved in the leptin-melanocortin pathway. In addition, unlike the obesity genes previously identified, variants in BSN and APBA1 are not associated with childhood obesity. 

This has led the researchers to think that they may have uncovered a new biological mechanism for obesity, different to those we already know for previously identified obesity gene variants.

Based on published research and laboratory studies they report in this paper, which indicate that BSN and APBA1 play a role in the transmission of signals between brain cells, the researchers suggest that age-related neurodegeneration could be affecting appetite control.

For this study, the researchers worked closely with AstraZeneca to replicate their findings in existing cohorts using genetic data from individuals from Pakistan and Mexico. This is important as the researchers can now apply their findings beyond individuals of European ancestry.

If the researchers can better understand the neural biology of obesity, it could present more potential drug targets to treat obesity in the future.

Protein-truncating variants in BSN are associated with severe adult-onset obesity, type 2 diabetes and fatty liver disease, Nature Genetics (2024). DOI: 10.1038/s41588-024-01694-x

Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 11:38am

Cancer-busting vaccines are coming: here's how they work

Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 11:32am

But Clyde Francks, a geneticist and neuroscientist at the Max Planck Institute for Psycholinguistics in Nijmegen, the Netherlands, and his team looked for genetic variants in protein-coding sequences. Their analysis of 313,271 right-handed and 38,043 left-handed individuals’ genetic data, from the UK Biobank, uncovered variants in a tubulin gene, dubbed TUBB4B, which were 2.7 times more common in left-handed people than in right-handers.

Microtubules could influence handedness because they form cilia — hair-like protrusions in cell membranes — which can direct fluid flows in an asymmetric way during development.

In spite of affecting only a small proportion of the people in this considerable data set, rare variants “can give clues to developmental mechanisms of brain asymmetry in everyone”, these findings pave the way for future work to determine how microtubules, which themselves have a molecular ‘handedness’, can give an “asymmetric twist” to early brain development.

https://www.nature.com/articles/s41467-024-46277-w?utm_source=Live+...

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Part 2

Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 11:30am

A reason for right- or left-handedness
Researchers examined rare genetic variants from a database of more than 350,000 individuals’ genetic data to hunt for clues for what influences handedness in humans. Their findings implicate tubulins — proteins that build cells’ internal skeletons.

The results, published on 2 April in Nature Communications1, were obtained specifically at protein-coding parts of the DNA, and add to previous studies that linked genetic variations with handedness .
During the embryonic stage of human development, the left and right brain hemispheres get wired differently, which in part determines innate behaviours, such as where we lean when we hug someone, on which side of our mouth we tend to chew our food and, most prominently, which hand is our dominant one. This turns out to be the left hand for around 10% of the human population.

Because most people have a clear preference for one hand over the other, finding genes linked to handedness can provide clues for the genetic basis of the brain’s left–right asymmetry.
Previous studies looking at genome-wide data from UK Biobank2 found 48 common genetic variants associated with left-handedness, which were mostly in non-coding regions of the DNA. These included sections that could control the expression of genes related to tubulins. These proteins assemble into long, tube-like filaments called microtubules, which control the shapes and movements of cells.
Part 1

Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 10:12am

In a few years, it could result in implementing a negative leap second to keep atomic and astronomical time in sync, although the impacts of polar ice melt could end up delaying our need to shift the clocks from 2026 to 2029.

Would adjusting the clocks by a second make that much of a difference? It could impact global systems in a major way.

Although our computer infrastructure is equipped to handle positive leap seconds, essentially none of our networks or web services are equipped for negative leap seconds.

They don't know how to go from 12:00:03 to 12:00:02. This is essentially on par with the Y2K bug where you had to reprogram everything to allow for four-digit years.

Similar to Y2K,  it likely wouldn't actually end up causing catastrophe. Although it could impact the precision timekeeping community and atomic time, the alternative to letting "a couple of seconds float" is "reprogramming the internet." In that case, a little lost time might not be a bad thing.

This story is republished courtesy of Northeastern Global News news.northeastern.edu.

https://news.northeastern.edu/2024/04/02/climate-change-earth-rotat...

Part 3

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Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 10:08am

Glacial melt that has been taking place since the Ice Age and, more recently, polar ice melt stemming from manmade climate change have also contributed to the Earth's slowing rotation.

In both cases, the meltwater disperses, creating a mass of water around the equator, while, at the same time, the land previously trapped under ice at the poles springs back up.

Those two forces together make it more difficult for the Earth to rotate, meaning the UTC day is technically longer. This phenomenon has been observed for decades.

"As the glaciers melt and as Earth slowly springs back and as mass that was once at the poles gets redistributed to the equators—because liquid spreads more easily, liquid responds to being spun—the rotation rate of the Earth slows down.

However, more recently scientists have discovered that Earth is not slowing down anymore. In fact, it's starting to speed up ever so slightly. Leap seconds were added almost every year between 1972 and 1999 to adjust for Earth's slowing rotation. But there have only been four added in the last 23 years, and the last time a leap second was added was in 2016.

What scientists have found is that although climate change is "applying the brakes", the liquid part of Earth's core is also slowing down, affecting how fast the surface of the planet spins.

"The core of the Earth, the liquid part, rotates too, and it sometimes just experiences random changes, random fluctuations.

Right now, the core of the Earth in the last few decades has randomly slowed down and by a complicated series of interactions between the liquid part of the core and the mantle and the crust, or the solid part of the Earth, the crust is spinning faster. This random change in the core's rotation, specifically a slowing down in the rate of rotation, translates into a speeding up of the Earth's surface rotating, which would have the effect of shortening days.

Part 2

Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 10:06am

Why do we need a leap second? A physicist explains what is messing with the Earth's rotation
Meltwater from the polar ice caps, combined with the shifting spin of Earth's core, is messing with the Earth's rotation to the point that we might need to adjust for a "negative leap second."

The effects of climate change can be seen everywhere, in the global refugee crisis, an even worse allergy season and, now, even in the very concept of time.

Scientists have recently pinpointed how meltwater from the polar ice caps is throwing off Earth's rotation to the point that those who really care about precision timekeeping might have to implement a "negative leap second."

Does that mean our days will suddenly be 25 hours long? No, but even a change of one second is significant in a world that is built on digital systems, like GPS, that rely on precise timekeeping to operate correctly.

The core, the crust, oceans, climate change, glacial isostatic adjustment –– all of these factors [are] contributing to a change in the Earth's rate of rotation at a measurable pace, something that would accumulate a second per year or something like that.

There are two primary methods of timekeeping. Universal Coordinated Time (UTC), also known as astronomical time because it's based on Earth's rotation and position among the stars, has long been used as the global standard for clocks and timekeeping. It's what time zones are based on and what most people think of as "time."

However, Earth's rotation is not exactly a steady drumbeat. It's actually always changing as the sun, moon and Earth's gravitational forces, as well as Earth's tides and even the rotation of its core, play off one another.

To account for this, timekeepers—requiring a more exacting standard—started using atomic time, or International Atomic Time, to come up with the exact speed that our clocks tick. This measure varies so little that it might as well be static. In 1958, the international time keeping community agreed to synchronize both UTC and TAI. However, in 1972, scientists noticed that Earth's rotation was starting to slow ever so slightly, effectively making the days slightly longer. As a result, atomic and astronomical time began to diverge slowly but steadily. To keep them in sync—an increasing necessity as more and more digital systems, like GPS satellites, require even more exacting levels of precision—the "leap second" was created.

there are several factors responsible for the declining pace of Earth's rotation, including what is called tidal locking.

The moon pulls on Earth, Earth pulls on the moon and over time the effect of that is for the Earth to slow down in a minuscule—like one part in 10 billion—but non negligible way.

Part 1

Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 9:45am

Studies have since shown that exposure to some PFAS—there are at least 4,000 chemical compounds in the family—may be linked to serious health effects in humans and animals.
The European Union is considering a blanket Europe-wide ban on PFAS from as early as 2026 while New Zealand will outlaw their use in cosmetic products by 2027.

In April, a US court approved a litigation settlement in which the conglomerate 3M agreed to pay billions to test for and filter out PFAS in public water supply.

In February, US regulators said materials containing PFAS would no longer be used to package microwave popcorn or other greasy foods.
Establishing the possible long-term harms of PFAS exposure is difficult when considering such a kaleidoscope of chemicals, many of which are industry secrets.
Those known to scientists are "only the tip of the iceberg".
Examining the full spectrum of chemicals is critical to better understanding their impact on nature.
A wild organism is never exposed to a single PFAS, but to a cocktail of PFAS.

Source: AFP and other news agencies

Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 9:43am

From polar bears to groundwater, nature is riddled with 'forever chemicals'

They didn't exist a century ago but today PFAS "forever chemicals" contaminate the environment from groundwater to Antarctic snow to turtle eggs, and concern over their possible toxicity is growing.

Lawsuits and regulations targeting per- and polyfluoroalkyl substances (PFAS) are multiplying, with France becoming the latest jurisdiction to consider tough new curbs on these long-life substances.

On Thursday, a French legislator will introduce a bill to address what he calls the health "emergency" posed by exposure to PFAS in the environment.

Widely used in everyday items, highly durable, and very slow to break down, PFAS have been detected in water, air, fish and soil in the remotest corners of the globe.

No ecosystem has escaped this contamination. 

These molecules—the best known of which gave birth to non-stick Teflon—were developed after World War II to give packaging, paints and coatings exceptional resistance to water or heat.

This very quality turned out to be a particular problem for oceans. Being persistent compounds—which do not degrade and are mobile—they end up in the marine environment, which always ultimately is the receptacle for contamination.

A study published in January by the American Chemical Society, a nonprofit scientific organisation, said that PFAS had ben detected in the Arctic Ocean at a depth of 3,000 feet (914 metres).

IFREMER recently examined the diets of two fish—sea bass and sole—in the Seine estuary of France and discovered PFAS riddled throughout the food chain.

From the tiny zooplankton eaten by shellfish, which are consumed by smaller fish and ultimately larger predators, PFAS lurked at every step along the way.

A 2022 study in Australia established the transmission of PFAS from female turtles to their unborn offspring, while other research found traces in polar bear livers and birds, seals and other animals.

A wealth of scientific research has demonstrated the pervasive reach of PFAS in nature, but possible harms to people and the planet have been harder to definitively establish.

More than 20 years ago, a study in the US concluded that once inside the body PFAS may be able to reach the brain of vertebrates and affect the nervous system.

Part 1

Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 9:24am

NASA wants to come up with a new clock for the moon, where seconds tick away faster

NASA wants to come up with an out-of-this-world way to keep track of time, putting the moon on its own  clock.

It's not quite a time zone like those on Earth, but an entire frame of time reference for the moon. Because there's less gravity on the moon, time there moves a tad quicker—58.7 microseconds every day—compared to Earth. So the White House Tuesday instructed NASA and other U.S agencies to work with international agencies to come up with a new moon-centric time reference system.

An atomic clock on the moon will tick at a different rate than a clock on Earth. It makes sense that when you go to another body, like the moon or Mars that each one gets its own heartbeat.

So everything on the moon will operate on the speeded-up moon time.

The last time NASA sent astronauts to the moon they wore watches, but timing wasn't as precise and critical as it now with GPS, satellites and intricate computer and communications systems. Those microseconds matter when high tech systems interact.

Last year, the European Space Agency said Earth needs to come up with a unified time for the moon, where a day lasts 29.5 Earth days. The International Space Station, being in low Earth orbit, will continue to use coordinated universal time or UTC. But just where the new space time kicks in is something that NASA has to figure out. Even Earth's time speeds up and slows down, requiring leap seconds.

The White House wants NASA to come up with a preliminary idea by the end of the year and have a final plan by the end of 2026.

NASA is aiming to send astronauts around the moon in September 2025 and land people there a year later.

Source:  The Associated Press and other News agencies

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