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Comment by Dr. Krishna Kumari Challa on February 11, 2023 at 11:19am

Scientists develop test that can identify respiratory viruses within five minutes

Scientists have developed a world-first diagnostic test, powered by artificial intelligence, that can identify known respiratory viruses within five minutes from just one nasal or throat swab. The new diagnostic test could replace current methods that are limited to testing for only one infection—such as a lateral flow test for COVID-19—or otherwise are either lab-based and time-consuming or fast and less accurate.

The new virus detection and identification methodology is described in a paper published in ACS Nano. The paper demonstrates how machine learning can significantly improve the efficiency, accuracy and time taken to not only identify different types of viruses, but also differentiate between strains.

The ground-breaking testing technology combines molecular labeling, computer vision and machine learning to create a universal diagnostic imaging platform that looks directly at a patient sample and can identify which pathogen is present in a matter of seconds—much like facial recognition software, but for germs.

Preliminary research demonstrated that this test could identify the COVID-19 virus in patient samples and further work determined that the test could be used to diagnose multiple respiratory infections.

In the study, the researchers began by labeling viruses with single-stranded DNA in over 200 clinical samples from John Radcliffe Hospital. Images of labeled samples were captured using a commercial fluorescence microscope and processed by custom machine-learning software that is trained to recognize specific viruses by analyzing their fluorescence labels, which show up differently for every virus because their surface size, shape and chemistry vary.

The results show the technology is able to rapidly identify different types and strains of respiratory viruses, including flu and COVID-19, within five minutes and with >97% accuracy.

 Nicolas Shiaelis et al, Virus Detection and Identification in Minutes Using Single-Particle Imaging and Deep Learning, ACS Nano (2022). DOI: 10.1021/acsnano.2c10159

Comment by Dr. Krishna Kumari Challa on February 11, 2023 at 9:55am

Cockatoos know to bring along multiple tools when they fish for cashews

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

New land creation on waterfronts is increasing

Humans are artificially expanding cities' coastlines by extending industrial ports and creating luxury residential waterfronts. Developers have added over 2,350 square kilometers of land (900 square miles, or about 40 Manhattans) to coastlines in major cities since 2000, according to a new study.

The study reports the first global assessment of coastal land reclamation, which is the process of building new land or filling in coastal water bodies, including wetlands, to expand a coastline. The researchers used satellite imagery to analyze land changes in 135 cities with populations of at least 1 million, 106 of which have done some coastline expansion.

The study was published in the journal Earth's Future.

It's quite important to capture this. There are more and more people, and our footprint is going up. Inevitably, there are ecologic consequences.

The researchers found that  industrialization and a need for urban space have driven much coastal land reclamation, while a smaller proportion of expansion projects are for "prestige," such as the palm tree-shaped islands of Dubai.

About 70% of coastal land expansion has been carried out in low-lying regions that are likely to be exposed to extreme sea level rise by the end of the century. Both environmental impacts and projected coastal inundation suggest these developed coastlines are not sustainable, but cities will likely continue to build them, the researchers say.

Ecological impacts: 

New land is typically created by piling sediments in the ocean, building cement sea walls and structures to contain sediments or cement, or by filling in wetlands and other shallow water bodies near the coast. These methods require vast volumes of sediment and disturb ecosystems irreversibly, as other research has established.

The ecological impacts of reclamation are immense. Reclamation is a massive civil engineering project that fundamentally alters the characteristics of the space that it targets. Coastal wetlands are particularly hard-hit. In the Yellow Sea, for example, more than half of tidal flats were lost mainly due to reclamation.

The creation of land will make sense where it's needed, but you have to do it in a responsible way … and think about whether it is really needed. Those are value judgments.

Other environmental impacts include adding sources of point-source pollution, changing the patterns of sediment movement and altering the biosphere, all of which can impact ocean-based economies such as fishing and tourism. And unequal access to newly created shoreline can exacerbate class divides.

Reclamation also impacts distant ecosystems where fill materials such as sand and gravel are quarried. With a global shortage of sand,  construction companies are quarrying sand and clay from the seabed, which destroys benthic ecosystems.

Dhritiraj Sengupta et al, Mapping 21st Century Global Coastal Land Reclamation, Earth's Future (2023). DOI: 10.1029/2022EF002927

Comment by Dr. Krishna Kumari Challa on February 10, 2023 at 9:39am

Calorie restriction slows pace of aging in healthy adults

In a first of its kind randomized controlled trial an international team of researchers shows that caloric restriction can slow the pace of aging in healthy adults. The CALERIE intervention slowed pace of aging measured from participants' blood DNA methylation using the algorithm DunedinPACE (Pace of Aging, Computed from the Epigenome). The intervention effect on DunedinPACE represented a 2-3 percent slowing in the pace of aging, which in other studies translates to a 10-15 percent reduction in mortality risk, an effect similar to a smoking cessation intervention. The results are published online in the journal Nature Aging.

The CALERIE Phase-2 randomized controlled trial is the first ever investigation of the effects of long-term calorie restriction in healthy, non-obese humans. The trial randomized 220 healthy men and women at three sites in the U. S. to a 25 percent calorie-restriction or normal diet for two years. CALERIE is an acronym for 'Comprehensive Assessment of Long-Term Effects of Reducing Intake of Energy'.

To measure biological aging in CALERIE Trial participants, the researchers analyzed blood samples collected from trial participants at pre-intervention baseline and after 12- and 24-months of follow-up. Humans live a long time, so it isn't practical to follow them until we see differences in aging-related disease or survival. Instead, we rely on biomarkers developed to measure the pace and progress of biological aging over the duration of the study. The team analyzed methylation marks on DNA extracted from white blood cells. DNA methylation marks are chemical tags on the DNA sequence that regulate the expression of genes and are known to change with aging.

In the primary analysis teh researchers focused on three measurements of the DNA methylation data, sometimes known as "epigenetic clocks". The first two, the PhenoAge and GrimAge clocks, estimate biological age, or the chronological age at which a person's biology would appear "normal". These measures can be thought of as "odometers" that provide a static measure of how much aging a person has experienced. The third measure studied by the researchers was DunedinPACE, which estimates the pace of aging, or the rate of biological deterioration over time. DunedinPACE can be thought of as a "speedometer".

The study found evidence that calorie restriction slowed the pace of aging in humans. But calorie restriction is probably not for everyone. These findings are important because they provide evidence from a randomised trial that slowing human aging may be possible. They also give us a sense of the kinds of effects researchers might look for in trials of interventions that could appeal to more people, like intermittent fasting or time-restricted eating.

A follow-up of trial participants is now ongoing to determine if the intervention had long-term effects on healthy aging.

Daniel Belsky, Effect of long-term caloric restriction on DNA methylation measures of biological aging in healthy adults from the CALERIE trial, Nature Aging (2023). DOI: 10.1038/s43587-022-00357-y. www.nature.com/articles/s43587-022-00357-y

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

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