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On July 18 (Thursday), well-known foreignscienceThe main contents of the website are as follows:

Nature website (www.nature.com)

Blocking an inflammation-promoting protein extends lifespan in mice, may have the same effect in humans

A protein that promotes inflammation may be the key to extending healthy lifespan. Blocking the protein, called interleukin-11 (IL-11), in middle-aged mice boosted metabolism, reduced frailty and extended lifespan by about 25 percent.

Although the study was only tested in mice, IL-11 and its molecular partners — including the immune system's chemical messengers interleukins — are also found in humans. Drug candidates that block IL-11 are already in human trials for the treatment of cancer and fibrosis, a disease associated with aging.

The findings, published recently in the journal Nature, suggest that these potential treatments may also have an impact on human lifespan, but separate clinical trials will need to be conducted to determine that.

Researchers have long known that chronic inflammation can contribute to age-related diseases. The role of interleukin-11 in promoting inflammation has also been established. But the link between this protein and ageing was discovered by accident when molecular biologists at Duke-NUS Medical School were testing a method to detect interleukin-11.

One immune system expert said the results were surprising and should prompt further research. He said an important next step is to test candidate IL-11 drugs in mice with different genetic backgrounds and in multiple laboratories to ensure the results are reproducible.

Science website (www.science.org)

To prevent sea level rise, scientists envision using barriers to "enclose" the Earthglacier

Over the past few decades,EarthScientists have been studying the concept of solar geoengineering, such as injecting particles high into the atmosphere to reflect sunlight to cool a rapidly warming Earth. Now, researchers are proposing a new approach to combating the effects of climate change that could be more expensive and controversial: glacial geoengineering to slow sea level rise.

Glaciologists have held a series of workshops and symposia over the past 10 months and recently published a white paper calling for more research into bold plans to build new glaciers on the fragileice sheetProtecting fragile ice sheets could be done by building flexible barriers around them or drilling deep to slow their slide into the ocean.

But the untested ideas have drawn strong opposition from some glaciologists, who say they are costly, logistically flawed and a distraction from efforts to reduce greenhouse gas emissions.

John Moore, a glaciologist at the University of Lapland in Finland and one of the authors of the white paper, proposed in the report the idea of ​​building a buoyant "curtain": a curtain moored to the seafloor beyond the edges of ice shelves and glaciers to block the natural flow of warm water that erodes the ice sheet from below. According to the white paper, initial modeling studies have shown that a curtain extending only half the height from the seafloor off the coast of West Antarctica could reduce glacial melt by 10 times in some areas. Other interventions being considered by some scientists include slowing the slide of the ice sheet by drilling holes under the base of the ice sheet to pump out water or heat.

Such a massive engineering effort would surely be one of the most expensive ever undertaken by humanity. At a seminar at the University of California in October 2023, researchers said that building an 80-kilometer-long curtain around the Antarctic glacier could cost $88 billion. Such an intervention would also require international political support, which some glaciologists see as a greater obstacle than cost.

Science News website (www.sciencenews.org)

On JupiterGreat Red SpotThe history of existence may be less than 200 years

Jupiter's iconic feature — the Great Red Spot — may be different than the dark spot astronomers saw on the giant planet more than 300 years ago.

From 1665 to 1713, Italian astronomer Giovanni Domenico Cassini and others observed a dark oval on Jupiter that they called the "Permanent Spot," which was at the same latitude that the Great Red Spot rotates at today. Today's researchers wonder if they are one and the same.

An analysis of drawings and photographs of Jupiter spanning nearly 360 years suggests the spots are distinct, researchers reported recently in Geophysical Research Letters. Computer simulations from the same study also hinted at the Great Red Spot's origins, suggesting that a break in air flow between opposing jet streams could have set in motion Jupiter's massive red storm.

The researchers studied drawings of Jupiter that past planetary observers had sketched out as they viewed it through their telescopes. They found no signs of a permanent spot in reports of Jupiter beginning in 1713. Then, in 1831 and over the following decades, a spot similar to the Great Red Spot appeared on the drawings — a clear oval that turned red.

Measurements of the Permanent Spot from drawings showed it to be about one-third to one-half the width of the Great Red Spot photographed in 1879. The researchers concluded that the Permanent Spot disappeared from records for 118 years and its small size suggested it may have disappeared before the Great Red Spot appeared.

Science Daily website (www.sciencedaily.com)

1. Scientists discover that microorganisms can destroy certain "permanent chemicals"

A UC Riverside environmental engineering team has discovered specific bacterial species that can destroy certain "forever chemicals," another step toward low-cost treatment of contaminated drinking water sources.

These microorganisms belong to the genus Acetobacter, and they are common in wastewater environments around the world.

Forever chemicals, also known as per- and polyfluoroalkyl substances, or PFAS, are so named because they have stubbornly strong carbon-fluorine chemical bonds that make them persistent in the environment.

They report today in the journal Science Advances that they have discovered microbes that can split those stubborn fluorine-carbon bonds.

The researchers caution that the bacteria are only effective against unsaturated PFAS compounds, which have double carbon-to-carbon bonds in their chemical structure.

But importantly, the scientists also discovered the specific enzymes in these bacteria that are necessary to cleave the carbon-fluorine bond. This discovery opens the door for bioengineers to improve these enzymes so that they can be effective against other PFAS compounds.

Because PFAS compounds have been linked to cancer and other human health ailments, the U.S. Environmental Protection Agency (EPA) implemented water quality restrictions earlier this year that cap the level of certain permanent chemicals in tap water nationwide to 4 parts per trillion, prompting water suppliers to look for PFAS cleanup options.

2. Ancient viral DNA remains in human genes, which promotes modern cancer

Among the approximately 20,000 human genes, there are residual DNA fragments left over from viruses that infected human ancestors tens of millions of years ago.

These DNA fragments, called endogenous retroviruses, have long been considered inert or "junk" DNA without any destructive power. A recent study from the University of Colorado Boulder (CU Boulder) published in the journal Science Advances shows that when they are reawakened, they can play a key role in helping cancer survive and grow. The study also suggests that silencing certain endogenous retroviruses could make cancer treatments more effective.

To explore the role of endogenous retroviruses in cancer, the researchers analyzed genomic data from 21 human cancer types from publicly available datasets.

They found that a specific lineage of an endogenous retrovirus called LTR10, which infected some primates about 30 million years ago, showed surprisingly high levels of activity in several cancers, including lung and colon cancer. Further analysis of tumors from dozens of colorectal cancer patients showed that LTR10 was active in about a third of them.

When the team used the CRISPR gene-editing tool to snip out, or silence, the sequences present in LTR10, they found that key genes known to promote cancer development and growth also dimmed.

"We saw that when you silence this retrovirus in cancer cells, it turns off nearby gene expression," said Dr.

Scitech Daily website (https://scitechdaily.com)

Researchers discover new way to grow human cartilage

Researchers at the University of Montana and partners have discovered a new way to generate cartilage for the human head and neck. They have coaxed stem cells, which can replicate themselves and develop into different cell types, to become the types of cells that normally make up human craniofacial cartilage.

The research was published in the journal Science.

The cells that normally produce this cartilage are called neural crest cells, and they have discovered a new way to generate craniofacial organoids from neural crest cells.”

Organoids are simplified, miniature versions of organs that mimic their structure and gene expression. Organoids are good models for certain human tissues, allowing for some studies that would not be possible using human tissue.

The researchers studied gene expression data at both the RNA and protein levels to reveal how chondrocytes arise from stem cells. They found that the stem cells communicate with each other at an early stage to become the elastic cartilage that makes up the human ear.

To achieve this, the team used extensive biomarker analysis and machine learning pattern recognition techniques to understand the cell signaling pathways involved as cells differentiate into cartilage.

Current plastic surgery techniques have difficulty recreating natural features such as a person's ear, nose or throat, and transplanted tissue is often rejected without immunosuppressants.

"To use patient-derived stem cells to generate craniofacial cartilage in the laboratory, you need to understand the human-specific differentiation mechanism," said the researcher. "Our goal is to develop a protocol for craniofacial cartilage transplantation using human stem cells."