. Scientific Frontline

Friday, January 28, 2022

Climate change in the Early Holocene - archaeology report

New insight into how our early ancestors dealt with major shifts in climate is revealed in research by an international team, led by Professor Rick Schulting from Oxford University’s School of Archaeology.

  • Radiocarbon dating from a prehistoric cemetery in Northern Russia reveals human stress caused by a global cooling event 8,200 years ago.
  • Early hunter gatherers developed more complex social systems and, unusually, a large cemetery when faced by climate change

Published in Nature Ecology & Evolution, the report reveals, new radiocarbon dates show the large Early Holocene cemetery of Yuzhniy Oleniy Ostrov, at Lake Onega, some 500 miles north of Moscow, previously thought to have been in use for many centuries, was, in fact, used for only one to two centuries. Moreover, this seems to be in response to a period of climate stress.

"The team believes the creation of the cemetery reveals a social response to the stresses caused by regional resource depression...[it] would have helped define group membership for what would have been previously dispersed bands of hunter-gatherers - mitigating potential conflict over access to the lake’s resources"

The team believes the creation of the cemetery reveals a social response to the stresses caused by regional resource depression. At a time of climate change, Lake Onega, as the second largest lake in Europe, had its own ecologically resilient microclimate. This would have attracted game, including elk, to its shores while the lake itself would have provided a productive fishery. Because of the fall in temperature, many of the region’s shallower lakes could have been susceptible to the well-known phenomenon of winter fish kills, caused by depleted oxygen levels under the ice.

Thursday, January 27, 2022

Expanded University of Hawaiʻi asteroid tracking system can monitor entire sky

Left: Sutherland ATLAS station during construction in South Africa.
Credit: Willie Koorts (SAAO)
Right: Chilean engineers and astronomers installing the ATLAS telescope at El Sauce Observatory.

A state-of-the-art asteroid alert system operated by the University of Hawaiʻi Institute for Astronomy (IfA) can now scan the entire dark sky every 24 hours for dangerous bodies that could plummet toward Earth.

The NASA-funded Asteroid Terrestrial-impact Last Alert System (ATLAS) has expanded its reach to the southern hemisphere, from two existing northern-hemisphere telescopes on Haleakalā and Maunaloa. Construction is now complete and operations are underway on two additional telescopes in South Africa and Chile.

Telescope unit on Haleakalā, Maui.
Photo credit: Henry Weiland

Large Herbivores Help Rare Species Persist in a Warming Arctic

A herd of caribou in arctic Greenland. Caribou at this study site have been declining over the past several years, while muskoxen have been increasing. Such herbivores help rare plant species persist in a rapidly changing climate.
Credit: Eric Post/UC Davis

Being common is rather unusual. It’s far more common for a species to be rare, spending its existence in small densities throughout its range. How such rare species persist, particularly in an environment undergoing rapid climate change, inspired a 15-year study in arctic Greenland from the University of California, Davis.

Arctic wintergreen, a very rare species,
grows among birch and willow
shrubs near Kangerlussuaq, Greenland.
Credit: Eric Post/UC Davis
The study, published in the journal Scientific Reports, found that caribou and muskoxen helped mitigate the effects of climate change on rare arctic plants, lichens and mushrooms at the study site.

The authors suggest that by constraining the abundance of the two most common plant species — dwarf birch and gray willow — large herbivores may allow other, less common species to persist rather than be shaded or outcompeted for nutrients by the woody shrub’s canopy, or suppressed by leaf litter and cooler soils.

“This is more evidence that conserving large herbivores is really important to maintaining the compositional integrity of species-poor systems like the arctic tundra,” said lead author Eric Post, director of the UC Davis Polar Forum and a professor in the UC Davis Department of Wildlife, Fish and Conservation Biology.

Microbes help hibernating animals recycle nutrients, maintain muscle through winter

Like many hibernators, thirteen-lined ground squirrels retain muscle tone and healthy gut microbiomes through hibernation even though they aren’t eating or moving around. Their success at rest may help humans make long space voyages.
Credit: Rob Streiffer

To get through a long winter without food, hibernating animals — like the 13-lined ground squirrel — can slow their metabolism by as much as 99 percent, but they still need important nutrients like proteins to maintain muscles while they hibernate. A new study from the University of Wisconsin–Madison shows that hibernating ground squirrels get help from microbes in their guts.

The discovery could help people with muscle-wasting disorders and even astronauts on extended space voyages.

“The longer any animal doesn’t exercise, bones and muscles start to atrophy and lose mass and function,” says Hannah Carey, an emeritus professor in the UW–Madison School of Veterinary Medicine and co-author of the new study, published today (Jan. 27) in the journal Science. “Without any dietary protein coming in, hibernators need another way to get what their muscles need.”

One source of nitrogen, a vital building block for amino acids and proteins, accumulates in the bodies of all animals (including humans) as urea, a component of urine. The researchers knew that urea that moved into the squirrels’ digestive tract could be broken down by some gut microbes, which also need nitrogen for their own proteins. But the researchers wanted to see if some of that urea nitrogen freed up by the microbes was also being incorporated into the squirrels’ bodies.

Chemist Identifies New Way of Finding Extraterrestrial Life

SDSU researchers Chris Harrison and Jessica Torres, seen above in Harrison's lab, are using lasers and liquids to detect amino acids in extraterrestrial rocks. In the background, an image of Mars.
Source: San Diego State University

Have we been looking for extraterrestrials in all the wrong places? San Diego State University chemists are developing methods to find signs of life on other planets by looking for the building blocks of proteins in a place they've never been able to test before: inside rocks.

After collaborating with researchers at NASA’s Jet Propulsion Laboratory (JPL) in La Cañada Flintridge in 2019, Jessica Torres, a doctoral student studying chemistry at SDSU, is experimenting with ways to extract amino acids from porous rocks that could be used on future rovers.

Previous research has looked for evidence of other life forms in water and soil, but not from solid materials.

Current methods for identifying amino acids can’t differentiate versions created by a living organism from those formed through random chemical reactions. And existing techniques usually require water — which would freeze or evaporate if placed on a space probe traveling to Mars or Europa, the ice-covered saltwater moon of Jupiter that some regard as a prime candidate for extraterrestrial life because of its subsurface ocean.

Tumors dramatically shrink with new approach to cell therapy

Graphic of tumor-infiltrating lymphocites, natural immune cells that invade tumors.
Credit: Shana O. Kelley Lab/Northwestern University

Northwestern University researchers have developed a new tool to harness immune cells from tumors to fight cancer rapidly and effectively.

Their findings, published January 27 in the journal Nature Biomedical Engineering, showed a dramatic shrinkage in tumors in mice compared to traditional cell therapy methods. With a novel microfluidic device that could be 3D printed, the team multiplied, sorted through and harvested hundreds of millions of cells, recovering 400% more of the tumor-eating cells than current approaches.

Most treatments for cancer involve toxic chemicals and foreign substances, which cause harmful side effects and weaken the body’s immune response. Using tissue from one’s own body can eliminate side effects and risk of rejection, and many disease therapies in regenerative medicine and cancer treatment have gained traction in the clinic. But sometimes the wheels skid.

“People have been cured in the clinic of advanced melanoma through treatment with their own immune cells that were harvested out of tumor tissue,” said Shana O. Kelley, a pioneer in translational biotechnology and corresponding author on the paper. “The problem is, because of the way the cells are harvested, it only works in a very small number of patients.”

Uncontrolled Blood Pressure Is Sending More People to the Hospital

New research from the Smidt Heart Institute shows that more
people are being hospitalized for dangerously high blood pressure.
Photo by Cedars-Sinai.
The number of people hospitalized for a hypertensive crisis—when blood pressure increases so much it can cause a heart attack, stroke or other sudden cardiovascular event—more than doubled from 2002 to 2014, according to Cedars-Sinai investigators.

The increase occurred during a period when some studies reported overall progress in blood pressure control and a decline in related cardiovascular events in the U.S. The findings are published in the Journal of the American Heart Association.

“Although more people have been able to manage their blood pressure over the last few years, we’re not seeing this improvement translate into fewer hospitalizations for hypertensive crisis,” said Joseph E. Ebinger, MD, a clinical cardiologist and director of clinical analytics at the Smidt Heart Institute and first author of the study.

Ash trees may be more resilient to warming climate than previously believed

Students taking tree measurements in Penn State's green ash provenance trial are shown in this photo, circa 2000. Almost all the trees are dead and gone now, victims of the emerald ash borer. However, in the decades before they died — along with ash trees at other university trials and plantations and U.S. Forest Service installations — they offered an unprecedented perspective on how forests may be changed by a warming climate.
Credit: Kim Steiner / Penn State. Creative Commons

Since the 1990s, scientists have been predicting that North American tree species will disappear from portions of their ranges within the next 50 to 100 years because of projected changes in climate. A new study led by Penn State forest biologists found that when transplanted to warmer environments, ash trees can survive increased temperatures of 7 degrees Fahrenheit and sometimes even up to 18 degrees Fahrenheit, suggesting that these trees may be more resilient to climate warming than previously believed.

“We know that species distribution models based only on climate are biologically imperfect,” said lead researcher Kim Steiner, professor emeritus of forest biology in the College of Agricultural Sciences. “However, they are the best we have for predicting where species would be found in a climatically different future, and it is extremely difficult — especially with trees — to experimentally test and possibly refute such predictions."

Male carriers of BRCA1 and BRCA2 gene mutation also at risk of multiple cancers

The BRCA1 and BRCA2 gene mutations are well known for their female carriers to have increased risk of cancers, but new research reveals the increased risk of various cancers for male carriers.

People who carry the BRCA1 or BRCA2 gene mutation have an increased risk of pancreatic, stomach and prostate cancers, as well as the previously well-known risk of breast and ovarian cancers – but not for melanoma, according to new University of Melbourne led research calling for increased testing in male carriers to detect the cancers early.

The study used the largest sample size ever in a cancer study of the same kind worldwide, critiquing 22 cancers to establish that in addition to female breast and ovarian cancers, BRCA1/2 carriers are at risk for male breast, pancreatic, stomach and prostate (BRCA2 carriers only) cancers, but not other cancers as previously thought. Significantly, the study team found that BRCA1/2 carriers did not have higher risk of melanoma.

Lead author and Victorian Cancer Agency Early Career Research Fellow Dr Shuai Li said the research suggested male relatives of known BRCA1/2 carriers should be informed about their individual cancer risk.

“They should be informed about cancer risk and encouraged to be tested, because male and female carriers have the same cancer risks for pancreatic and stomach cancers, and male BRCA2 carriers also have increased risk of prostate cancers. Male carriers can also have increased risk of developing breast cancer. BRCA-related cancers are not a ‘female only’ thing,” Dr Shuai Li said.

Wednesday, January 26, 2022

Current anti-COVID pills work well against omicron, but antibody drugs are less effective

Yoshihiro Kawaoka
The drugs behind the new pills to treat COVID-19 remain very effective against the omicron variant of the virus in lab tests, according to a new study.

However, lab tests also showed that the available antibody therapies — typically given intravenously in hospitals — are substantially less effective against omicron than against earlier variants of the virus. The antibody treatments by Lilly and Regeneron have entirely lost their ability to neutralize omicron at realistic dosages. The Food and Drug Administration recently removed these two drugs from approved treatment lists because they are ineffective against the variant.

If the ability of the antiviral pills to combat omicron is confirmed in human patients, it would be welcome news. Public health officials expect the pills to become an increasingly common treatment for COVID-19 that will reduce the severity of the disease in at-risk patients and decrease the burden of the pandemic.

For now, the pills remain in short supply during the current omicron wave, which has broken case records in the U.S. and other countries.

The findings corroborate other studies that show most available antibody treatments are less effective against omicron. Drug makers could design, test and produce new antibody drugs targeted at the omicron variant to overcome the limitations of current therapies, but this process would take months.

“The bottom line is we have countermeasures to treat omicron. That’s good news,” says Yoshihiro Kawaoka, the University of Wisconsin–Madison lead of the study and virologist at the UW School of Veterinary Medicine and the University of Tokyo. “However, this is all in laboratory studies. Whether this translates into humans, we don’t know yet.”

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