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Comment by Dr. Krishna Kumari Challa on February 9, 2023 at 10:26am

The everyday chemicals that make us fatter

“There are at least 50 chemicals, probably many more, that literally make us fatter,” says environmental-health scientist Leonardo Trasande. He is among those researching ‘obesogens’ — chemicals, such as fungicides and flame retardants, that seem to ma.... The term was coined by cell biologist Bruce Blumberg, who discovered in 2006 that tributyltin chloride promoted fat formation in mice. His advice? “Do not eat packaged processed food. It’s full of obesogens. Buy fresh ingredients and make a meal.”

https://academic.oup.com/mend/article/20/9/2141/2738473

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Global supply chains are devouring what's left of Earth's unspoiled...

While farming continues to drive deforestation around the world, 60% of the destruction of Earth's large, intact forests is caused by other forces. In particular, our research shows that more than one-third of this destruction can be blamed on the production of commodities for export, particularly timber, minerals and oil and gas.

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Urgent environmental action needed to limit the spread of superbugs...

To reduce superbugs, world must cut down pollution and change how we behave, according to a new report by the UN.

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Light pollution has cut humanity's ancient connection with the star...

Humans are naturally afraid of the dark. We sometimes imagine monsters under the bed and walk faster down unlit streets at night. To conquer our fears, we may leave a night light on to scare away the monsters and a light over the porch to deter break-ins.

Comment by Dr. Krishna Kumari Challa on February 9, 2023 at 10:23am

How India is battling deadly rain storms

Grassroots action such as the flood early-warning system along the Meenachil River run by Eby Emmanuel is doing something India’s country-wide forecasts can’t: collating local knowledge to warn people of deadly rainstorms. The South Asian summer monsoon is a notoriously complex weather phenomenon. “Climate change is making [extreme rainfall] more erratic and the weather forecasting models are unable to account for that increase in chaos,” says climate scientist Roxy Koll. And forecasting models created in the United States and Europe do not account for how much South Asia’s farming practices and population can change the weather.

https://www.nature.com/articles/d41586-023-00341-5?utm_source=Natur...

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COVID drug might drive viral mutations

Molnupiravir, a drug widely used to treat COVID-19, might be spurring the evolution of new SARS-CoV-2 variants. The drug works by peppering the coronavirus’s genome with mutations, which add up to make SARS-CoV-2 worse at replicating. But scientists have raised the possibility that, in rare cases, molnupiravir treatment might not entirely eliminate SARS-CoV-2, allowing some individuals who have taken the drug to continue to transmit the virus. Now, a preprint study (which is not yet peer reviewed) of more than 13 million SARS-CoV-2 sequences has uncovered sequences that bear molnupiravir’s fingerprints. Quantitative bioscientist Rustem Ismagilov says the study underscores the need to quickly assess the risk of continued use of the drug. “If we are playing Russian roulette, we’d better know our odds.”

https://www.medrxiv.org/content/10.1101/2023.01.26.23284998v2

Comment by Dr. Krishna Kumari Challa on February 9, 2023 at 9:42am

Air pollution linked with blood pressure in London teens

In a new analysis involving adolescents living in London, exposure to higher levels of the pollutant nitrogen dioxide was associated with lower systolic blood pressure, while exposure to higher levels of particulate matter (PM_2.5) was associated with higher systolic blood pressure. Scientists presented these findings in the open-access journal PLOS ONE on February 8, finding that these associations are stronger for girls than for boys.

Exposure to air pollutants is linked to greater risk of cardio-respiratory disease, hospital visits, and death. Adolescents' rapidly growing bodies may be particularly susceptible to long-lasting effects of exposure to air pollutants, including effects on BP. However, most prior studies on air pollution and blood pressure have focused on adults.

For this analysis, they used data on 3,284 adolescents in DASH to examine associations between blood pressure and exposure to pollution in the form of nitrogen dioxide and PM2.5; exposures were estimated based on annual mean levels of pollutants where each participant lived. The researchers found that greater estimated exposure to nitrogen dioxide was associated with lower systolic blood pressure, and greater estimated exposure to PM2.5 was associated with higher systolic blood pressure. These associations were stronger in girls than in boys. No evidence of a relationship between nitrogen dioxide/PM2.5 and diastolic blood pressure was observed. For example, a 1μg/m3 increase in nitrogen dioxide was associated with a 0.30 mmHg (95% CI 0.18 to 0.40) decrease in systolic blood pressure for girls and 0.19 mmHg (95% CI 0.07 to 0.31) decrease in systolic blood pressure for boys. Meanwhile, a 1μg/m3 increase in PM2.5 was associated with a 1.34 mmHg (95% CI 0.85 to 1.82) increase in systolic blood pressure for girls and 0.57 mmHg (95% CI 0.04 to 1.03) increase in systolic blood pressure for boys. The associations between pollutants and blood pressure were consistent regardless of ethnicity, body size, or socioeconomic status. Eighty percent of the adolescents studied were from ethnic minority groups, and the residential estimates suggest that these adolescents were exposed to higher levels of the pollutants than their white peers.

The researchers call for further studies to help confirm and clarify these findings, particularly among young people from different socioeconomic backgrounds.

 Associations between air pollutants and blood pressure in an ethnically diverse cohort of adolescents in London, England, PLoS ONE (2023). DOI: 10.1371/journal.pone.0279719

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Comment by Dr. Krishna Kumari Challa on February 9, 2023 at 9:33am

Could we use Space dust as Earth's Sun-shield? Researchers are exploring this idea

On a cold winter day, the warmth of the sun is welcome. Yet as humanity emits more and more greenhouse gases, the Earth's atmosphere traps more and more of the sun's energy and steadily increases the Earth's temperature. One strategy for reversing this trend is to intercept a fraction of sunlight before it reaches our planet. For decades, scientists have considered using screens, objects or dust particles to block just enough of the sun's radiation—between 1 or 2%—to mitigate the effects of global warming.

A new study  explored the potential of using dust to shield sunlight. They analyzed different properties of dust particles, quantities of dust and the orbits that would be best suited for shading Earth. The authors found that launching dust from Earth to a way station at the "Lagrange Point" between Earth and the sun (L1) would be most effective but would require astronomical cost and effort. An alternative is to use moondust. The authors argue that launching lunar dust from the moon instead could be a cheap and effective way to shade the Earth.

The team of astronomers applied a technique used to study planet formation around distant stars, their usual research focus. Planet formation is a messy process that kicks up lots of astronomical dust that can form rings around the host star. These rings intercept light from the central star and re-radiate it in a way that we can detect it on Earth. One way to discover stars that are forming new planets is to look for these dusty rings.

That was the seed of the idea; if we took a small amount of material and put it on a special orbit between the Earth and the sun and broke it up, we could block out a lot of sunlight with a little amount of mass. It is amazing to contemplate how moon dust—which took over four billion years to generate—might help slow the rise in Earth's temperature, a problem that took us less than 300 years to produce.

The authors, however,  stress that this study only explores the potential impact of this strategy, rather than evaluate whether these scenarios are logistically feasible.

Dust as a solar shield, PLOS Climate (2023). DOI: 10.1371/journal.pclm.0000133 , journals.plos.org/climate/arti … journal.pclm.0000133

Comment by Dr. Krishna Kumari Challa on February 9, 2023 at 9:14am

Donor hearts can be reprogrammed with medication for longer storage, improved transplant outcomes

Although thousands of people are sick with heart failures around the world,  only around few heart transplants are performed annually.

One reason for this gap is the time window during which a heart can survive outside the donor body before transplant hovers around four hours. And the longer it takes for the donor heart to be transported to the recipient, the more likely that heart will not work well once it's implanted.

Using a drug previously used to treat seizures, researchers have found a way to reprogram donor hearts to boost the production of a beneficial enzyme that both increases the amount of time they can be stored and transported, as well as improves their function after they are transplanted, a study published in Science Translational Medicine suggests. This technology that coaxes donor hearts to mount adaptive responses to existence outside the body could lead to a paradigm shift not only for extending the time a heart can be outside of the donor during transport but for improving heart function after transplant.

Being able to extend the storage of hearts by figuring out the pathways that define and modulate preservation biology is the first step toward the ultimate goal of organ banking.

Current donor preservation techniques focus on cold storage and, more recently, technologies that keep the organs perfused during transport to minimize injury to the heart, but there are no targeted molecular therapies to improve heart preservation in a very precise fashion.

When an organ is in cold storage, succinate is free to build up in excess—more ammunition for stress against the soon-to-be-transplanted heart. To reprogram hearts to take on the heart-damaging succinate, researchers used valproic acid, a histone deacetylase inhibitor previously used as an anti-seizure medication. They found that it defused a significant amount of this cumulative stress in both human and pig hearts by instructing the donor heart to produce antioxidants and anti-inflammatory proteins while preserved on ice.

Using a metabolomic screen, researchers found that valproic acid can reprogram the donor heart to produce beneficial itaconate during preservation.

Ienglam Lei et al, Metabolic reprogramming by immune-responsive gene 1 upregulation improves donor heart preservation and function, Science Translational Medicine (2023). DOI: 10.1126/scitranslmed.ade3782. www.science.org/doi/10.1126/scitranslmed.ade3782

Comment by Dr. Krishna Kumari Challa on February 9, 2023 at 9:05am

Three hallmarks of aging work together to prevent cancer: 

telomeres, mitochondria, and inflammation

As we age, the end caps of our chromosomes, called telomeres, gradually shorten. Now,  scientists have discovered that when telomeres become very short, they communicate with mitochondria, the cell's powerhouses. This communication triggers a complex set of signaling pathways and initiates an inflammatory response that destroys cells that could otherwise become cancerous.

The findings, published in Nature on February 8, 2023, could lead to new ways of preventing and treating cancer as well as designing better interventions to offset the harmful consequences of aging.

It is surprising to note that telomeres talk to mitochondria. They clearly synergize in well-controlled biological processes to initiate cellular pathways that kill cells that could cause cancer.

When telomeres shorten to a point where they can no longer protect chromosomes from damage, a process called "crisis" occurs and cells die. This beneficial natural process removes cells with very short telomeres and unstable genomes and is known to be a powerful barrier against cancer formation. Cells in crisis are removed by a process called autophagy, in which the body rids itself of damaged cells.

 Jan Karlseder, Telomere-to-mitochondria signalling by ZBP1 mediates replicative crisis, Nature (2023). DOI: 10.1038/s41586-023-05710-8. www.nature.com/articles/s41586-023-05710-8

Comment by Dr. Krishna Kumari Challa on February 9, 2023 at 8:33am

A new ring system discovered in our solar system

Scientists have discovered a new ring system around a dwarf planet on the edge of the solar system. The ring system orbits much further out than is typical for other ring systems, calling into question current theories of how ring systems are formed.

The ring system is around a dwarf planet, named Quaoar, which is approximately half the size of Pluto and orbits the sun beyond Neptune.

The discovery, published in Nature, was made by an international team of astronomers using HiPERCAM—an extremely sensitive high speed camera developed by scientists at the University of Sheffield which is mounted on the world's largest optical telescope, the 10.4 meter diameter Gran Telescopio Canarias (GTC) on La Palma.

The rings are too small and faint to see directly in an image. Instead, the researchers made their discovery by observing an occultation, when the light from a background star was blocked by Quaoar as it orbits the sun. The event lasted less than a minute, but was unexpectedly preceded and followed by two dips in light, indicative of a ring system around Quaoar.

Ring systems are relatively rare in the solar system. In addition to the well-known rings around the giant planets Saturn, Jupiter, Uranus and Neptune, only two other minor planets possess rings—Chariklo and Haumea. All of the previously known ring systems are able to survive because they orbit close to the parent body, so that tidal forces prevent the ring material from accreting and forming moons.

What makes the ring system around Quaoar remarkable is that it lies at a distance of over seven planetary radii—twice as far out as what was previously thought to be the maximum radius according to the so-called "Roche limit," which is the outer limit of where ring systems were thought to be able to survive. For comparison, the main rings around Saturn lie within three planetary radii. This discovery has therefore forced a rethink on theories of ring formation.

Bruno Morgado, A dense ring of the trans-Neptunian object Quaoar outside its Roche limit, Nature (2023). DOI: 10.1038/s41586-022-05629-6. www.nature.com/articles/s41586-022-05629-6

Comment by Dr. Krishna Kumari Challa on February 8, 2023 at 10:54am

What generative AI means for science

Some scientists now frequently use generative artificial-intelligence (AI) systems, such as ChatGPT, to help them write and edit manuscripts, check their code and brainstorm ideas. But the excitement about the use of such tools is tempered with apprehe..., because of their propensity to make factual errors, reproduce biases in training data and provide fuel for fakery. They also rely on humans to tag reams of violent, abusive and other horrific content so that it can be filtered out, and require a huge amount of energy to train. Researchers are grappling with these issues, in part by urging more regulation and transparency.

https://www.nature.com/articles/d41586-023-00340-6?utm_source=Natur...

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If wormholes exist, they might magnify light by 100,000 times

A small team of astrophysicists affiliated with several institutions in China has found evidence that suggests if wormholes are real, they might magnify light by 100,000 times. In their paper published in the journal Physical Review Letters, the group describes the theories they have developed and possible uses for them.

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This exoplanet orbits around its star's poles

In 1992, humanity's effort to understand the universe took a significant step forward. That's when astronomers discovered the first exoplanets. They're named Poltergeist (Noisy Ghost) and Phobetor (Frightener), and they orbit a pulsar about 2300 light-years away.

Comment by Dr. Krishna Kumari Challa on February 8, 2023 at 10:22am

New way climate change is fueling itself

Healthy, undisturbed soil sinks carbon, storing what's generated when plants and other living things decompose so it doesn't get released as a planet-warming greenhouse gas.

But a new study  suggests nitrogen pollution from cars and trucks and power plants might make soil release that carbon in dry places—worsening, rather than helping to fight, climate change.

In places that get more regular rain and snow, other studies have shown that adding nitrogen to soil can increase carbon storage. Nitrogen fuels plant growth, which captures carbon and draws it down into the soil. It also helps slow decomposition of whatever is in the soil.

Dryland ecosystems cover roughly 45% of land on Earth. They also store 33% of the carbon found in the top layer of soil worldwide. So if nitrogen pollution is making the carbon stored in these soils vulnerable, that definitely rings some alarm bells.

The findings offer new motivation, then, to speed the transition away from fossil fuels and cut back on nitrogen-rich fertilizer if we want to slow global warming that's already creating climate refugees due to worsening heat waves, droughts, floods and wildfires.

https://phys.org/news/2023-02-dirty-truth-climate-fueling.html?utm_...

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Comment by Dr. Krishna Kumari Challa on February 7, 2023 at 12:38pm

Scientists Create Semi-Living 'Cyborg' Cells That Could Transform Medicine

Through a complex chemical process, scientists have been able to develop versatile, synthetic 'cyborg' cells in the lab. They share many characteristics of living cells while lacking the ability to divide and grow.

That non-replication part is important. For artificial cells to be useful, they need to be carefully controlled, and that can't happen as easily if they're propagating in the same way that actual cells do.

The researchers behind the new development think these cyborgs could have a huge variety of applications, from improving treatments for diseases like cancer to cleaning up pollution through targeted chemical processes.

The cyborg cells are programmable, do not divide, preserve essential cellular activities, and gain nonnative abilities.

Cell engineering is currently based on two key approaches: genetically remodeling existing cells to give them new functions (more flexible but also able to reproduce) and building synthetic cells from scratch (which can't replicate but have limited biological functions).

These cyborg cells are the result of a new, third strategy. The researchers took bacterial cells as their foundation and added elements from an artificial polymer. Once inside the cell, the polymer was exposed to ultraviolet light to build it into a hydrogel matrix by cross-linking, mimicking a natural extracellular matrix.

While able to maintain much of their normal biological functions, these cyborg cells proved to be more resistant to stressors like high pH and antibiotic exposure – stressors that would kill off normal cells. Much like actual cyborgs, they're tough.

Cyborg cells preserve essential functions, including cellular metabolism, motility, protein synthesis, and compatibility with genetic circuits.

Lab tests on tissue samples showed that the newly developed cells were able to invade cancer cells, highlighting the potential of these modified biological building blocks for health treatments further down the line – they could one day be used to deliver drugs to very specific parts of the body.

he researchers say they now want to experiment with the use of different materials to create these cells, as well as investigate how they could be used.

It's also not clear exactly what is stopping the cells from replicating, which needs to be determined. The authors think the hydrogel matrix may stop cell division by inhibiting cell growth or DNA replication, or both.

The blending of the natural and the artificial demonstrated here in some ways takes the best elements of both, opening up new possibilities – a state of "quasi vita" or "almost life", as the researchers put it.

https://onlinelibrary.wiley.com/doi/10.1002/advs.202204175

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