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Comment by Dr. Krishna Kumari Challa on December 11, 2020 at 7:14am

Blocking protein restores strength, endurance in old mice, study finds

Muscle loss during aging is known as sarcopenia, and it accounts for billions of dollars of health care expenditures  each year as people lose the ability to care for themselves, experience more falls and become increasingly less mobile. It is due to changes in muscle structure and function: The muscle fibers shrink and the number and function of the cellular powerhouses known as mitochondria dwindle.

Blocking the activity of a single protein in old mice for one month restores mass and strength to the animals' withered muscles and helps them run longer on a treadmill, according to a study by researchers. Conversely, increasing the expression of the protein in young mice causes their muscles to atrophy and weaken.

The improvement is really quite dramatic. The old mice are about 15% to 20% stronger after one month of treatment, and their muscle fibres look like young muscle. Considering that humans lose about 10% of muscle strength per decade after about age 50, this is quite remarkable.

The protein hasn't previously been implicated in aging. The researchers show that the amount of the protein, called 15-PGDH, is elevated in old muscle and is widely expressed in other old tissues. Experiments they conducted in human tissue raise hopes for a future treatment for the muscle weakness that occurs as people age.

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Prostaglandin E2 levels are regulated by 15-PGDH, which breaks down prostaglandin E2. The researchers used a highly sensitive version of mass spectrometry, a method for differentiating closely related molecules, to determine that compared with young mice, the 15-PGDH levels are elevated in the muscles of older animals, and the levels of prostaglandin E2 are lower.

They found a similar pattern of 15-PGDH expression in human muscle tissues, as those from people in their 70s and early 80s expressed higher levels than those from people in their mid-20s.

"We knew from our previous work that prostaglandin E2 was beneficial for regeneration of young muscles.

"Inhibition of prostaglandin-degrading enzyme 15-PGDH rejuvenates aged muscle mass and strength" Science (2020). science.sciencemag.org/lookup/ … 1126/science.abc8059

https://medicalxpress.com/news/2020-12-blocking-protein-strength-mi...

Comment by Dr. Krishna Kumari Challa on December 10, 2020 at 12:02pm

This Teen's Brilliantly Simple Explainer on Quantum Mechanics Just Won a Global Prize

https://www.sciencealert.com/17-year-old-wins-global-science-prize-...

Comment by Dr. Krishna Kumari Challa on December 10, 2020 at 11:31am

Dogs Probably Don't Understand Us as Well as We Think, Brain Scans Reveal

Dogs may never learn that every sound of a word matters

https://www.sciencealert.com/dogs-may-not-actually-understand-us-as...

Comment by Dr. Krishna Kumari Challa on December 10, 2020 at 10:32am

These simple steps can help prevent heat-related fatalities

Comment by Dr. Krishna Kumari Challa on December 10, 2020 at 10:25am

Scientists discover how COVID-19 virus causes multiple organ failure in mice

 Researchers  created a version of COVID-19 in mice that shows how the disease damages organs other than the lungs. Using their model, the scientists discovered that the SARS-CoV-2 virus can shut down energy production in cells of the heart, kidneys, spleen and other organs.

Understanding how this virus can hijack our cells might eventually lead to new ways to prevent or treat the organ failure that can accompany COVID-19 in humans. 

Research in humans has suggested that SARS-CoV-2 can circulate through the bloodstream to reach multiple organs. So in the UCLA experiment, the researchers first engineered mice to have the human version of ACE2 in the heart and other vital organs. Then, they infected half of the animals by injecting SARS-CoV-2 into their bloodstreams. Over the following days, the researchers tracked the animals’ overall health and analyzed how levels of certain genes and proteins in their bodies changed.

Within seven days, all of the mice with COVID-19 had stopped eating and were completely inactive, and had lost, on average, about 20% of their body weight. Animals that had been engineered to carry the human ACE2 protein but had not been infected with the virus, on the other hand, did not lose a significant amount of weight.

Moreover, the COVID-19 infected animals had altered levels of immune cells, swelling of the heart tissue and wasting away of the spleen — all symptoms that have been observed in people who are critically ill with COVID-19.

The research team also looked at which genes were turned on and off in the mice infected with SARS-CoV-2, and they discovered other signs of disease. Common molecular processes that help cells generate energy — through mechanisms known as the tricarboxylic acid cycle, or TCA cycle, and electron transport chain — were shut off in the heart, kidney, spleen and lungs.

If a virus snuffs out the energy-generating pathways in multiple organs of the body, that’s going to really wreak havoc.

The study also revealed that some changes were long-lasting throughout the organs in mice with COVID-19. In addition to temporarily altering which genes were turned on and off in some cells, the virus made epigenetic changes — chemical alterations to the structure of DNA that cause more lasting effects. This could explain why, in some people with COVID-19, symptoms persist for weeks or months after their bodies are rid of the virus.

https://newsroom.ucla.edu/releases/covid-19-multiple-organ-failure-...

https://researchnews.cc/news/4027/Scientists-discover-how-COVID-19-...

Comment by Dr. Krishna Kumari Challa on December 10, 2020 at 10:16am

Pesticides in contact with plastic mulch take longer to degrade

The use of plastic mulch (plastic covering on crop lines) is a widespread technique used in agricultural regions in order to increase the profitability of the crops. According to the European Commission, 100,000 tons of plastic mulch was used per year in the European Union in 2016. Taking these figures into account and the fact that after the harvest some plastic usually remains in the soil, the accumulation of plastic in territories of intensive agriculture is an environmental problem that is of concern in the sector and also for public administration.

Comment by Dr. Krishna Kumari Challa on December 10, 2020 at 10:10am

Why did Mount Everest's height change?

The world's highest mountain is now officially a little higher. China and Nepal presented a new official figure of 8,848.86 meters (29,031.69 feet) above sea level. 

China and Nepal agreed this week on a new standard height for Mount Everest. Geological changes, the complicated business of measuring a mountain and varying criteria for determining the world's highest peak will likely ensure the question isn't settled for good.

The mountain's height changes. The movement of tectonic plates can lift it up ever so gradually, while earthquakes can bring it down.

The countervailing forces may help maintain a degree of stability over time.

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There's more than one way to measure a mountain.

Last year, a Nepalese team set up a satellite navigation marker on Everest's peak to gauge its exact position via GPS satellites. A Chinese team undertook a similar mission this spring, though it used the Chinese-made Beidou constellation of navigation satellites, along with other equipment.

At the same time, Nepalese crews took measurements with modern, laser-equipped versions of instruments called theodolites, first used to gauge the mountain's height in 1856 by measuring angles using trigonometry.

The Nepalese team also used ground penetrating radar to measure the amount of snow and ice that sits on top of its highest rock.

The new height is 0.86 meters (more than 2 feet) above the higher of the countries' two previous figures, that given by Nepal. The two had diverged for year over the mountain's actual height.

Measuring the height above sea level has always been tricky because ocean levels vary considerably depending on tides, magnetism and other factors. Rising sea levels are creating another factor for future measurements.

How high above sea level is just one way of measuring a mountain's height. One reason Everest wins the prize is that its base sits high up on already lofty foothills.

As measured from the Earth's core, Ecuador's Mount Chimborazo is the world's highest, standing more than 2,072 meters (6,800 feet) above Everest. Because the Earth bulges in the middle, mountains along the equator are farther from the core.

Measuring from the foot of the mountain to the peak, Hawaii's Mauna Kea is the tallest. Most of it, however, is under the sea.

https://phys.org/news/2020-12-mount-everest-height.html?utm_source=...

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Comment by Dr. Krishna Kumari Challa on December 10, 2020 at 10:03am

Manmade mass now outweighs life on Earth: study

For the first time in history manmade materials now likely outweigh all life on Earth, scientists said recently in research detailing the "crossover point" at which humanity's footprint is heavier than that of the natural world.

The weight of roads, buildings and other constructed or manufactured materials is doubling roughly every 20 years, and authors of the research said it currently weighed 1.1 teratonnes (1.1 trillion tonnes).

As mankind has ramped up its insatiable consumption of natural resources, the weight of living biomass—trees, plants and animals—has halved since the agricultural revolution to stand at just 1 teratonne currently, the study found.

Estimating changes in global biomass and manmade mass since 1990, the research showed that the mass of human-produced objects stood at just three percent of the weight of biomass at the start of the 20th century.

But since the post-World War II global production boom, manufacturing has surged to the extent that humans now produce the equivalent of the weight of every person on Earth every week on average.

Global human-made mass exceeds all living biomass, Nature (2020). DOI: 10.1038/s41586-020-3010-5 , www.nature.com/articles/s41586-020-3010-5

https://phys.org/news/2020-12-manmade-mass-outweighs-life-earth.htm...

Comment by Dr. Krishna Kumari Challa on December 10, 2020 at 8:40am

Space weather discovery puts 'habitable planets' at risk

A discovery that links stellar flares with radio-burst signatures will make it easier for astronomers to detect space weather around nearby stars outside the Solar System. Unfortunately, the first weather reports from our nearest neighbour, Proxima Centauri, are not promising for finding life as we know it.

Astronomers have recently found there are two 'Earth-like' rocky planets around Proxima Centauri, one within the 'habitable zone' where any water could be in liquid form. 

Proxima Centauri is just 4.2 light years from Earth.

But given Proxima Centauri is a cool, small red-dwarf star, it means this habitable zone is very close to the star; much closer in than Mercury is to our Sun.

Some present research shows is that this makes the planets very vulnerable to dangerous ionising radiation that could effectively sterilise the planets. astronomers have for the first time shown a definitive link between optical flares and radio bursts on a star that is not the Sun. The finding, published today in The Astrophysical Journal, is an important step to using radio signals from distant stars to effectively produce space weather reports.

 Astrophysical Journal (2020). DOI: 10.3847/1538-4357/abca90

https://phys.org/news/2020-12-space-weather-discovery-habitable-pla...

Comment by Dr. Krishna Kumari Challa on December 9, 2020 at 11:06am

It's Not Just Humans. Sparrows Have Been Seen Using Preventative Medicine

 we might not be the only species that knows certain things in nature can help treat our ills.

A new correspondence paper has put forward the idea that russet sparrows (Passer cinnamomeus) in China are using wormwood (Artemisia verlotorum) leaves in their nest as a preventative medicine, to reduce parasites and help their babies get bigger.

The conclusion that animals can use medicinal plants to their benefit is not necessarily new
 Pregnant elephants in Kenya eat a particular leaf to induce birth, while many other mammals use medicinal plants to self-medicate – sometimes to prevent disease or just generally feel better from an ailment.

But it's still pretty amazing that a tiny sparrow might know that some plants are more important than others for protecting against disease.

"In China, russet sparrows incorporate wormwood leaves into their nests around the same time that local people hang wormwood from their doors as a traditional custom during the Dragon Boat Festival

The belief that this behaviour confers protection against ill health is supported by the description of anti-parasite compounds in wormwood. It has been suggested that the incorporation of fresh wormwood leaves into nests may serve a similar function for sparrows. the birds actively seek out nest locations close to the available wormwood and resupply established nests with fresh wormwood leaves gathered based solely on the leaves smell.

The nests containing wormwood leaves had lower parasite loads. By decreasing the number of parasites such as mites, the sparrows that add more wormwood leaves to their nest produce heavier and healthier chicks.

Sparrows use a medicinal herb to defend against parasites and increase offspring condition

https://www.cell.com/current-biology/fulltext/S0960-9822(20)31525-6

https://www.sciencealert.com/sparrows-have-been-seen-using-preventa...

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