Eating red meat and processed meat hikes heart disease and death risk, study finds

Processed meats (stock image).

After a controversial study last fall recommending that it was not necessary for people to change their diet in terms of red meat and processed meat, a large, carefully analyzed new study links red and processed meat consumption with slightly higher risk of heart disease and death, according to a new study from Northwestern Medicine and Cornell University.

Eating two servings of red meat, processed meat or poultry -- but not fish -- per week was linked to a 3 to 7% higher risk of cardiovascular disease, the study found. Eating two servings of red meat or processed meat -- but not poultry or fish -- per week was associated with a 3% higher risk of all causes of death.

"It's a small difference, but it's worth trying to reduce red meat and processed meat like pepperoni, bologna and deli meats," said senior study author Norrina Allen, associate professor of preventive medicine at Northwestern University Feinberg School of Medicine. "Red meat consumption also is consistently linked to other health problems like cancer."

"Modifying intake of these animal protein foods may be an important strategy to help reduce the risk of cardiovascular disease and premature death at a population level," said lead study author Victor Zhong, assistant professor of nutritional sciences at Cornell, who did the research when he was a postdoctoral fellow in Allen's lab.

The paper will be published Feb. 3 in JAMA Internal Medicine.

The new findings come on the heels of a controversial meta-analysis published last November that recommended people not reduce the amount of red meat and processed meat they eat. "Everyone interpreted that it was OK to eat red meat, but I don't think that is what the science supports," Allen said.

"Our study shows the link to cardiovascular disease and mortality was robust," Zhong said.

What should we eat?

"Fish, seafood and plant-based sources of protein such as nuts and legumes, including beans and peas, are excellent alternatives to meat and are under-consumed in the U.S.," said study coauthor Linda Van Horn, professor of preventive medicine at Feinberg who also is a member of the 2020 U.S. Dietary Guidelines Advisory committee.

The study found a positive association between poultry intake and cardiovascular disease, but the evidence so far isn't sufficient to make a clear recommendation about poultry intake, Zhong said. Still, fried chicken is not recommended.

The new study pooled together a large diverse sample from six cohorts, included long follow-up data up to three decades, harmonized diet data to reduce heterogeneity, adjusted a comprehensive set of confounders and conducted multiple sensitivity analyses. The study included 29,682 participants (mean age of 53.7 years at baseline, 44.4% men and 30.7% non-white). Diet data were self-reported by participants, who were asked a long list of what they ate for the previous year or month.

Key findings:

• A 3 to 7% higher risk of cardiovascular disease and premature death for people who ate red meat and processed meat two servings a week.
• A 4% higher risk of cardiovascular disease for people who ate two servings per week of poultry, but the evidence so far is not sufficient to make a clear recommendation about poultry intake. And the relationship may be related to the method of cooking the chicken and consumption of the skin rather than the chicken meat itself.
• No association between eating fish and cardiovascular disease or mortality.

Limitations of the study are participants' dietary intake was assessed once, and dietary behaviors may have changed over time. In addition, cooking methods were not considered. Fried chicken, especially deep fat-fried sources that contribute trans-fatty acids, and fried fish intake have been positively linked to chronic diseases, Zhong said.

Other Northwestern authors are Dr. Philip Greenland, Dr. Mercedes R. Carnethon, Dr. Hongyan Ning, Dr. John T. Wilkins and Dr. Donald M. Lloyd-Jones.

The study was funded by National Institutes of Health/National Heart, Lung, and Blood Institute (R21 HL085375), American Heart Association Strategically Focused Research Networks and the Feinberg School of Medicine.

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Materials provided by Northwestern University. Original written by Marla Paul. Note: Content may be edited for style and length.

Normal resting heart rate appears to vary widely from person to person

Monitoring heart rate (stock image).

A person's normal resting heart rate is fairly consistent over time, but may vary from others' by up to 70 beats per minute, according to analysis of the largest dataset of daily resting heart rate ever collected. Giorgio Quer of the Scripps Research Translational Institute in La Jolla, California, and colleagues present these findings in the open-access journal PLOS ONE on February 5, 2020 as part of an upcoming PLOS Collection on Digital Health Technology.

A routine visit to the doctor usually involves a measurement of resting heart rate, but such measurements are rarely actionable unless they deviate significantly from a "normal" range established by population-level studies. However, wearables that track heart rate now provide the opportunity to continuously monitor heart rate over time, and identify normal resting heart rates at the individual level.

In the largest study of its kind to date, Quer and colleagues retrospectively analyzed de-identified heart rate data from wearables worn for a median of 320 days by 92,457 people from across the U.S. Nearly 33 million days' worth of heart rate data were collected in total. The researchers used the data to examine variations in resting heart rate for individuals over time, as well as between individuals with different characteristics.

The analysis showed that one person's mean daily resting heart rate may differ by up to 70 beats per minute from another person's normal rate. Taken together, age, sex, body mass index (BMI), and average daily sleep duration accounted for less than 10 percent of the observed variation between individuals.

The authors observed also a small seasonal trend in the resting heart rate, with slightly higher values observed in January and slightly lower values in July. The researchers also found that some individuals may occasionally experience brief periods when their resting heart rate differs by 10 or more beats per minute from their normal range.

These findings suggest the potential value of further research to investigate whether tracking a person's daily resting heart rate could enable earlier detection of clinically important changes.

The authors add: "Day-to-day changes in resting heart rate could be the first true, individualized digital vital sign, which is only now possible to measure thanks to wearable sensor technologies. We analyzed the extent of inter- and intra-individual changes in resting heart rate over a prolonged period of time, showing distinct patterns of variation according to age and sex, time of the year, average sleep duration and body mass index. These variations in resting heart rate may allow for the identification of early unexpected changes in an individuals' health."

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Nanoparticle chomps away plaques that cause heart attacks

Illustration of atherosclerotic plaque in blood vessel (stock image).

Michigan State University and Stanford University scientists have invented a nanoparticle that eats away -- from the inside out -- portions of plaques that cause heart attacks.

Bryan Smith, associate professor of biomedical engineering at MSU, and a team of scientists created a "Trojan Horse" nanoparticle that can be directed to eat debris, reducing and stabilizing plaque. The discovery could be a potential treatment for atherosclerosis, a leading cause of death in the United States.

The results, published in the current issue of Nature Nanotechnology, showcases the nanoparticle that homes in on atherosclerotic plaque due to its high selectivity to a particular immune cell type -- monocytes and macrophages. Once inside the macrophages in those plaques, it delivers a drug agent that stimulates the cell to engulf and eat cellular debris. Basically, it removes the diseased/dead cells in the plaque core. By reinvigorating the macrophages, plaque size is reduced and stabilized.

Smith said that future clinical trials on the nanoparticle are expected to reduce the risk of most types of heart attacks, with minimal side effects due to the unprecedented selectivity of the nanodrug.

Smith's studies focus on intercepting the signaling of the receptors in the macrophages and sending a message via small molecules using nano-immunotherapeutic platforms. Previous studies have acted on the surface of the cells, but this new approach works intracellularly and has been effective in stimulating macrophages.

"We found we could stimulate the macrophages to selectively eat dead and dying cells -- these inflammatory cells are precursor cells to atherosclerosis -- that are part of the cause of heart attacks," Smith said. "We could deliver a small molecule inside the macrophages to tell them to begin eating again."

This approach also has applications beyond atherosclerosis, he added.

"We were able to marry a groundbreaking finding in atherosclerosis by our collaborators with the state-of-the-art selectivity and delivery capabilities of our advanced nanomaterial platform. We demonstrated the nanomaterials were able to selectively seek out and deliver a message to the very cells needed," Smith said. "It gives a particular energy to our future work, which will include clinical translation of these nanomaterials using large animal models and human tissue tests. We believe it is better than previous methods."

Smith has filed a provisional patent and will begin marketing it later this year.

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Pluto's icy heart makes winds blow

Pluto (stock image).

A "beating heart" of frozen nitrogen controls Pluto's winds and may give rise to features on its surface, according to a new study.

Pluto's famous heart-shaped structure, named Tombaugh Regio, quickly became famous after NASA's New Horizons mission captured footage of the dwarf planet in 2015 and revealed it isn't the barren world scientists thought it was.

Now, new research shows Pluto's renowned nitrogen heart rules its atmospheric circulation. Uncovering how Pluto's atmosphere behaves provides scientists with another place to compare to our own planet. Such findings can pinpoint both similar and distinctive features between Earth and a dwarf planet billions of miles away.

Nitrogen gas -- an element also found in air on Earth -- comprises most of Pluto's thin atmosphere, along with small amounts of carbon monoxide and the greenhouse gas methane. Frozen nitrogen also covers part of Pluto's surface in the shape of a heart. During the day, a thin layer of this nitrogen ice warms and turns into vapor. At night, the vapor condenses and once again forms ice. Each sequence is like a heartbeat, pumping nitrogen winds around the dwarf planet.

New research in AGU's Journal of Geophysical Research: Planets suggests this cycle pushes Pluto's atmosphere to circulate in the opposite direction of its spin -- a unique phenomenon called retro-rotation. As air whips close to the surface, it transports heat, grains of ice and haze particles to create dark wind streaks and plains across the north and northwestern regions.

"This highlights the fact that Pluto's atmosphere and winds -- even if the density of the atmosphere is very low -- can impact the surface," said Tanguy Bertrand, an astrophysicist and planetary scientist at NASA's Ames Research Center in California and the study's lead author.

Most of Pluto's nitrogen ice is confined to Tombaugh Regio. Its left "lobe" is a 1,000-kilometer (620-mile) ice sheet located in a 3-kilometer (1.9-mile) deep basin named Sputnik Planitia -- an area that holds most of the dwarf planet's nitrogen ice because of its low elevation. The heart's right "lobe" is comprised of highlands and nitrogen-rich glaciers that extend into the basin.

"Before New Horizons, everyone thought Pluto was going to be a netball -- completely flat, almost no diversity," Bertrand said. "But it's completely different. It has a lot of different landscapes and we are trying to understand what's going on there."

Western winds

Bertrand and his colleagues set out to determine how circulating air -- which is 100,000 times thinner than that of Earth's -- might shape features on the surface. The team pulled data from New Horizons' 2015 flyby to depict Pluto's topography and its blankets of nitrogen ice. They then simulated the nitrogen cycle with a weather forecast model and assessed how winds blew across the surface.

The group discovered Pluto's winds above 4 kilometers (2.5 miles) blow to the west -- the opposite direction from the dwarf planet's eastern spin -- in a retro-rotation during most of its year. As nitrogen within Tombaugh Regio vaporizes in the north and becomes ice in the south, its movement triggers westward winds, according to the new study. No other place in the solar system has such an atmosphere, except perhaps Neptune's moon Triton.

The researchers also found a strong current of fast-moving, near-surface air along the western boundary of the Sputnik Planitia basin. The airflow is like wind patterns on Earth, such as the Kuroshio along the eastern edge of Asia. Atmospheric nitrogen condensing into ice drives this wind pattern, according to the new findings. Sputnik Planitia's high cliffs trap the cold air inside the basin, where it circulates and becomes stronger as it passes through the western region.

The intense western boundary current's existence excited Candice Hansen-Koharcheck, a planetary scientist with the Planetary Science Institute in Tucson, Arizona who wasn't involved with the new study.

"It's very much the kind of thing that's due to the topography or specifics of the setting," she said. "I'm impressed that Pluto's models have advanced to the point that you can talk about regional weather."

On the broader scale, Hansen-Koharcheck thought the new study was intriguing. "This whole concept of Pluto's beating heart is a wonderful way of thinking about it," she added.

These wind patterns stemming from Pluto's nitrogen heart may explain why it hosts dark plains and wind streaks to the west of Sputnik Planitia. Winds could transport heat -- which would warm the surface -- or could erode and darken the ice by transporting and depositing haze particles. If winds on the dwarf planet swirled in a different direction, its landscapes might look completely different.

"Sputnik Planitia may be as important for Pluto's climate as the ocean is for Earth's climate," Bertrand said. "If you remove Sputnik Planitia -- if you remove the heart of Pluto -- you won't have the same circulation," he added.

The new findings allow researchers to explore an exotic world's atmosphere and compare what they discover with what they know about Earth. The new study also shines light on an object 6 billion kilometers (3.7 billion miles) away from the sun, with a heart that captivated audiences around the globe.

"Pluto has some mystery for everybody," Bertrand said.

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Pluto's icy heart makes winds blow

Pluto (stock image).

A "beating heart" of frozen nitrogen controls Pluto's winds and may give rise to features on its surface, according to a new study.

Pluto's famous heart-shaped structure, named Tombaugh Regio, quickly became famous after NASA's New Horizons mission captured footage of the dwarf planet in 2015 and revealed it isn't the barren world scientists thought it was.

Now, new research shows Pluto's renowned nitrogen heart rules its atmospheric circulation. Uncovering how Pluto's atmosphere behaves provides scientists with another place to compare to our own planet. Such findings can pinpoint both similar and distinctive features between Earth and a dwarf planet billions of miles away.

Nitrogen gas -- an element also found in air on Earth -- comprises most of Pluto's thin atmosphere, along with small amounts of carbon monoxide and the greenhouse gas methane. Frozen nitrogen also covers part of Pluto's surface in the shape of a heart. During the day, a thin layer of this nitrogen ice warms and turns into vapor. At night, the vapor condenses and once again forms ice. Each sequence is like a heartbeat, pumping nitrogen winds around the dwarf planet.

New research in AGU's Journal of Geophysical Research: Planets suggests this cycle pushes Pluto's atmosphere to circulate in the opposite direction of its spin -- a unique phenomenon called retro-rotation. As air whips close to the surface, it transports heat, grains of ice and haze particles to create dark wind streaks and plains across the north and northwestern regions.

"This highlights the fact that Pluto's atmosphere and winds -- even if the density of the atmosphere is very low -- can impact the surface," said Tanguy Bertrand, an astrophysicist and planetary scientist at NASA's Ames Research Center in California and the study's lead author.

Most of Pluto's nitrogen ice is confined to Tombaugh Regio. Its left "lobe" is a 1,000-kilometer (620-mile) ice sheet located in a 3-kilometer (1.9-mile) deep basin named Sputnik Planitia -- an area that holds most of the dwarf planet's nitrogen ice because of its low elevation. The heart's right "lobe" is comprised of highlands and nitrogen-rich glaciers that extend into the basin.

"Before New Horizons, everyone thought Pluto was going to be a netball -- completely flat, almost no diversity," Bertrand said. "But it's completely different. It has a lot of different landscapes and we are trying to understand what's going on there."

Western winds

Bertrand and his colleagues set out to determine how circulating air -- which is 100,000 times thinner than that of Earth's -- might shape features on the surface. The team pulled data from New Horizons' 2015 flyby to depict Pluto's topography and its blankets of nitrogen ice. They then simulated the nitrogen cycle with a weather forecast model and assessed how winds blew across the surface.

The group discovered Pluto's winds above 4 kilometers (2.5 miles) blow to the west -- the opposite direction from the dwarf planet's eastern spin -- in a retro-rotation during most of its year. As nitrogen within Tombaugh Regio vaporizes in the north and becomes ice in the south, its movement triggers westward winds, according to the new study. No other place in the solar system has such an atmosphere, except perhaps Neptune's moon Triton.

The researchers also found a strong current of fast-moving, near-surface air along the western boundary of the Sputnik Planitia basin. The airflow is like wind patterns on Earth, such as the Kuroshio along the eastern edge of Asia. Atmospheric nitrogen condensing into ice drives this wind pattern, according to the new findings. Sputnik Planitia's high cliffs trap the cold air inside the basin, where it circulates and becomes stronger as it passes through the western region.

The intense western boundary current's existence excited Candice Hansen-Koharcheck, a planetary scientist with the Planetary Science Institute in Tucson, Arizona who wasn't involved with the new study.

"It's very much the kind of thing that's due to the topography or specifics of the setting," she said. "I'm impressed that Pluto's models have advanced to the point that you can talk about regional weather."

On the broader scale, Hansen-Koharcheck thought the new study was intriguing. "This whole concept of Pluto's beating heart is a wonderful way of thinking about it," she added.

These wind patterns stemming from Pluto's nitrogen heart may explain why it hosts dark plains and wind streaks to the west of Sputnik Planitia. Winds could transport heat -- which would warm the surface -- or could erode and darken the ice by transporting and depositing haze particles. If winds on the dwarf planet swirled in a different direction, its landscapes might look completely different.

"Sputnik Planitia may be as important for Pluto's climate as the ocean is for Earth's climate," Bertrand said. "If you remove Sputnik Planitia -- if you remove the heart of Pluto -- you won't have the same circulation," he added.

The new findings allow researchers to explore an exotic world's atmosphere and compare what they discover with what they know about Earth. The new study also shines light on an object 6 billion kilometers (3.7 billion miles) away from the sun, with a heart that captivated audiences around the globe.

"Pluto has some mystery for everybody," Bertrand said.

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Materials provided by American Geophysical Union. Note: Content may be edited for style and length.

BPA replacement, BPS, hinders heart function, study reveals

BPA replacement, BPS, hinders heart function, study reveals

BPA's counterpart replacement BPS can hinder heart function within minutes of a single exposure, according to a new University of Guelph study.

The study is the first to show the instant effects bisphenol S (BPS) can have on the heart.

"We expected to find similar effects from BPS as we have with BPA, but not at the speed that it worked," said biomedical sciences professor Glen Pyle, who conducted the study with former master's student Melissa Ferguson. "This replacement chemical seems to be more potent."

Bisphenol A (BPA), a chemical used in plastic products, was banned from baby bottles in Canada in 2010 over concerns that it may leach into foods and cause hormone-related side effects. More manufacturers are now using BPS as a replacement in their products and labelling them as BPA-free.

When mice were given bisphenol BPA or BPS in amounts that mimicked typical human levels, their heart function worsened, especially in females, within minutes of exposure.

These findings are concerning, as endocrine receptors and metabolic pathways are similar in mice and humans, said Pyle.

"This study raises concerns about the safety of BPS as a replacement for BPA."

It's particularly worrisome for people with coronary heart disease, high blood pressure, diabetes or obesity, because the effects of BPS could increase the chance of a heart attack or make a heart attack more severe, he added.

"If the heart is in a precarious position, when you add a stressor you can make it worse."

Published recently in the journal Scientific Reports, the study entailed treating mouse hearts with BPA and BPS at levels typically seen in people. Each chemical on its own was found to depress heart function by dampening heart contractions causing slower blood flow. However, BPS had a quicker impact -- within five minutes of exposure.

"Previous research has looked at the chronic effects that can happen when exposed to BPS over days," said Pyle. "But we are the first to show how fast BPS can work. This is an important finding because it means you don't need to have a buildup of the chemical over time to experience its harmful effects."

BPA is found in plastics used for food packaging, including liners for metal cans and other containers, as well as in medical devices such as hospital intravenous lines and dental sealants.

Although the body gets rid of bisphenols quickly, their ubiquitous use in so many consumer goods means that the substance persists.

Pyle advocates banning the substitute chemical BPS from such consumer products as food and beverage packaging, toys and thermal paper receipts. He also suggests consumers reduce plastic use, including single-use plastics.

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A tiny Galaxy with a Big Heart!

Photo: Hubble image depicting galaxy ESO 495-21 at the center. From NASA/ESA

Evolution of our understanding of Black Holes (BH) has gone from the mathematical outcome with no physical counterpart, up to their detection at the center of various galaxies and visualization of their shadow through the reconstructed image presented for the first time just a few months ago by the EHT global initiative (https://resonancescience.org/the-first-image-of-a-black-hole-is-finally-here/). Now it is thought that every galaxy hosts a BH in its core. When the first BHs were inferred from cosmological observations, we believed they were an extravagant exceptional behavior in the universe. Since, they have proven not so exceptional as they are detected with increased frequency, but they remain an extravagancy, and not for the same reasons.

ESO 495-21 is a galaxy just 3.000 light years across in diameter, very small compared to the almost 53.000 of our Milky Way galaxy. Located 30 million light years away in the constellation of Pyxis, it presents two contrasting features with respect to our galaxy; it forms huge numbers of stars and it hosts an enormous BH in its center, much bigger that what could be expected by its galactic size.

Galaxies that form stars at exceptionally high rates -star nurseries- create stellar newborns up to 1000 times faster than our galaxy, and are called Starburst galaxies. ESO 495-21 is a dwarf starburst galaxy because it is small in size. Usually we would expect that bigger the galaxy more massive the BH in its center. If our galaxy hosts Sagittarius A*, a supermassive BH over four million times as massive as our Sun, one would expect Henize 2-10 -the BH at the center of ESO- to be much smaller. But, the second intriguing observation is that ESO 495-21 galaxy -a 3% size of our galaxy- hosts a supermassive BH at its core, million times as massive as our Sun, too!

This extremely unusual scenario raises questions about our current astrophysical models and the relation between Black holes, galaxies and the universe. This finding is a strong indication that black holes may have come first, and that galaxies form and evolve around them. The question is, how?

do the galaxies form first and then crush material at their centers into black holes, or do pre-existing black holes gather galaxies around them? Do they evolve together—or could the answer be something else entirely?

– ESA/Hubble Information Centre

The NASA/ESA studied the activity bursts and explored the very dense regions a few million years old within ESO 495-21, and the data comprising the images were gathered by the Hubble Space Telescope with the advance camera for surveys and the Wide Field Planetary Camera 2.

RSF in perspective:

This finding is a strong indication that Black Holes came first, so then a question remains… how can a galaxy form and evolve around it, if we have believed BHs to be devouring monsters? The Unified theory developed by Nassim Haramein finds that BHs not only came first but they are in fact the responsible for the matter and posterior galaxy formation, as he has claimed for more than 25 years. Fortunately, astronomical observations not only have been unable to discard his findings and on the contrary, they point out in that same direction. In this sense we could literally say that the BH at the core IS the pumping heart of the galaxy.

By Ines Urdaneta, Research Scientist at RSF

More at:

Hubble observed tiny galaxy with big heart: https://phys.org/news/2019-06-hubble-tiny-galaxy-big-heart.html

First recording of a blue whale's heart rate

Blue whale

Encased in a neon orange plastic shell, a collection of electronic sensors bobbed along the surface of the Monterey Bay, waiting to be retrieved by Stanford University researchers. A lunchbox-sized speck in the vast waters, it held cargo of outsized importance: the first-ever recording of a blue whale's heart rate.

This device was fresh off a daylong ride on Earth's largest species -- a blue whale. Four suction cups had secured the sensor-packed tag near the whale's left flipper, where it recorded the animal's heart rate through electrodes embedded in the center of two of the suction feet. The details of this tag's journey and the heart rate it delivered were published Nov. 25 in Proceedings of the National Academy of Sciences.

"We had no idea that this would work and we were skeptical even when we saw the initial data. With a very keen eye, Paul Ponganis -- our collaborator from the Scripps Institution of Oceanography -- found the first heart beats in the data," said Jeremy Goldbogen, assistant professor of biology in the School of Humanities Sciences at Stanford and lead author of the paper. "There were a lot of high fives and victory laps around the lab."

Analysis of the data suggests that a blue whale's heart is already working at its limit, which may explain why blue whales have never evolved to be bigger. The data also suggest that some unusual features of the whale's heart might help it perform at these extremes. Studies like this add to our fundamental knowledge of biology and can also inform conservation efforts.

"Animals that are operating at physiological extremes can help us understand biological limits to size," said Goldbogen. "They may also be particularly susceptible to changes in their environment that could affect their food supply. Therefore, these studies may have important implications for the conservation and management of endangered species like blue whales."

Penguins to whales

A decade ago, Goldbogen and Ponganis measured the heart rates of diving emperor penguins in Antarctica's McMurdo Sound. For years after, they wondered whether a similar task could be accomplished with whales.

"I honestly thought it was a long shot because we had to get so many things right: finding a blue whale, getting the tag in just the right location on the whale, good contact with the whale's skin and, of course, making sure the tag is working and recording data," said Goldbogen.

The tag performed well on smaller, captive whales, but getting it near a wild blue whale's heart is a different task. For one thing, wild whales aren't trained to flip belly-up. For another, blue whales have accordion-like skin on their underside that expands during feeding, and one such gulp could pop the tag right off.

"We had to put these tags out without really knowing whether or not they were going to work," recalled David Cade, a recent graduate of the Goldbogen Lab who is a co-author of the paper and who placed the tag on the whale. "The only way to do it was to try it. So we did our best."

Cade stuck the tag on his first attempt and, over time, it slid into a position near the flipper where it could pick up the heart's signals. The data it captured showed striking extremes.

When the whale dove, its heart rate slowed, reaching an average minimum of about four to eight beats per minute -- with a low of two beats per minute. At the bottom of a foraging dive, where the whale lunged and consumed prey, the heart rate increased about 2.5 times the minimum, then slowly decreased again. Once the whale got its fill and began to surface, the heart rate increased. The highest heart rate -- 25 to 37 beats per minutes -- occurred at the surface, where the whale was breathing and restoring its oxygen levels.

An elastic heart

This data was intriguing because the whale's highest heart rate almost outpaced predictions while the lowest heart rate was about 30 to 50 percent lower than predicted. The researchers think that the surprisingly low heart rate may be explained by a stretchy aortic arch -- part of the heart that moves blood out to the body -- which, in the blue whale, slowly contracts to maintain some additional blood flow in between beats. Meanwhile, the impressively high rates may depend on subtleties in the heart's movement and shape that prevent the pressure waves of each beat from disrupting blood flow.

Looking at the big picture, the researchers think the whale's heart is performing near its limits. This may help explain why no animal has ever been larger than a blue whale -- because the energy needs of a larger body would outpace what the heart can sustain.

Now, the researchers are hard at work adding more capabilities to the tag, including an accelerometer, which could help them better understand how different activities affect heart rate. They also want to try their tag on other members of the rorqual whale group, such as fin whales, humpbacks and minke whales.

"A lot of what we do involves new technology and a lot of it relies on new ideas, new methods and new approaches," said Cade. "We're always looking to push the boundaries of how we can learn about these animals."

Additional Stanford co-authors include graduate students Max Czapanskiy, James Fahlbusch, William Gough and Shirel Kahane-Rapport and postdoctoral fellow Matt Savoca. Ponganis is senior author of the paper and additional co-authors are from Cascadia Research Collective; the University of California, Santa Cruz; and Scripps Institution of Oceanography. Goldbogen is also a member of Stanford Bio-X.

This research was funded by the Office of Naval Research, a Terman Fellowship from Stanford University and the John B. McKee Fund at Scripps Institution of Oceanography.

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Materials provided by Stanford University. Original written by Taylor Kubota. Note: Content may be edited for style and length.

A runaway star ejected from the galactic heart of darkness

A runaway star ejected from the galactic heart of darkness

Astronomers have spotted an ultrafast star, traveling at a blistering 6 million km/h, that was ejected by the supermassive black hole at the heart at the Milky Way five million years ago.

The discovery of the star, known as S5-HVS1, was made by Carnegie Mellon University Assistant Professor of Physics Sergey Koposov as part of the Southern Stellar Stream Spectroscopic Survey (S5). Located in the constellation of Grus -- the Crane -- S5-HVS1 was found to be moving ten times faster than most stars in the Milky Way.

"The velocity of the discovered star is so high that it will inevitably leave the galaxy and never return," said Douglas Boubert from the University of Oxford, a co-author on the study.

Astronomers have wondered about high velocity stars since their discovery only two decades ago. S5-HVS1 is unprecedented due to its high speed and close passage to the Earth, "only" 29 thousand light years away. With this information, astronomers could track its journey back into the center of the Milky Way, where a four million solar mass black hole, known as Sagittarius A*, lurks.

"This is super exciting, as we have long suspected that black holes can eject stars with very high velocities. However, we never had an unambiguous association of such a fast star with the galactic center," said Koposov, the lead author of this work and member of Carnegie Mellon's McWilliams Center for Cosmology. "We think the black hole ejected the star with a speed of thousands of kilometers per second about five million years ago. This ejection happened at the time when humanity's ancestors were just learning to walk on two feet."

Superfast stars can be ejected by black holes via the Hills Mechanism, proposed by astronomer Jack Hills thirty years ago. Originally, S5-HSV1 lived with a companion in a binary system, but they strayed too close to Sagittarius A*. In the gravitational tussle, the companion star was captured by the black hole, while S5-HVS1 was thrown out at extremely high speed.

"This is the first clear demonstration of the Hills Mechanism in action," said Ting Li from Carnegie Observatories and Princeton University, and leader of the S5 Collaboration. "Seeing this star is really amazing as we know it must have formed in the galactic center, a place very different to our local environment. It is a visitor from a strange land."

The discovery of S5-HVS1 was made with the 3.9-meter Anglo-Australian Telescope (AAT) near Coonabarabran, NSW, Australia, coupled with superb observations from the European Space Agency's Gaia satellite, that allowed the astronomers to reveal the full speed of the star and its journey from the center of the Milky Way.

"The observations would not be possible without the unique capabilities of the 2dF instrument on the AAT," said Daniel Zucker, an astronomer at Macquarie University in Sydney, Australia, and a member of the S5 executive committee. "It's been conducting cutting-edge research for over two decades and still is the best facility in the world for our project."

These results were published on November 4 online in the Monthly Notices of the Royal Astronomical Society, and the S5 collaboration unites astronomers from the United States, United Kingdom, Australia and Chile.

"I am so excited this fast-moving star was discovered by S5," says Kyler Kuehn, at Lowell Observatory and a member of the S5 executive committee. "While the main science goal of S5 is to probe the stellar streams -- disrupting dwarf galaxies and globular clusters -- we dedicated spare resources of the instrument to searching for interesting targets in the Milky Way, and voila, we found something amazing for 'free.' With our future observations, hopefully we will find even more!"

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Probing the role of an inflammation resolution sensor in obesity and heart failure

After heart attack injury, several fatty-acid-derived bioactive molecules -- including one called resolvin D1 -- play an essential signaling role to safely clear inflammation and help repair heart muscle. The mechanism of how this resolution occurs is not well-understood.

There is a receptor on the surface of many immune cells called ALX/FRP2, and in models of atherosclerosis, ALX/FPR2 is known to act as a sensor to help resolve inflammation.

In a 2015 study using a mouse model, University of Alabama at Birmingham researcher Ganesh Halade, Ph.D., observed that, after heart attack injury, ALX/FPR2 was highly expressed in immune myeloid cells and was activated by resolvin D1 in immune cells in the spleen and in immune cells at the heart attack site. The result was an expedited resolution of the heart attack injury. Resolvin D1 is one of the omega 3 fatty-acid metabolites known as specialized pro-resolving mediators, or SPMs, that help clear inflammation.

Now, Halade and colleagues at UAB, Boston and France have used mice that completely lack ALX/FPR2 to learn more about the pathways this resolution sensor uses to target inflammation. Such knowledge will help in finding treatments to delay the human heart failure that often follows a heart attack.

Before beginning the mouse studies, Halade and colleagues examined heart muscle tissue from patients with heart failure. They found that ALX/FPR2 was plentiful in these human ischemic hearts, and it was located in the cytoplasm of the myocardium cells. In contrast, in healthy human heart tissue, ALX/FPR2 was limited to the cell membrane. To learn more, they then expanded study of the precise and comprehensive role of the resolution receptor using mice having an ALX/FPR2 gene deletion.

The researchers found that mice lacking ALX/FPR2 showed spontaneous, age-related obesity. With the obesity, the ALX/FPR2-null mice developed heart disease that weakened the heart's ability to pump blood, and they had a shortened lifespan with aging. The aging mice also developed kidney inflammation, as shown by increased inflammation markers like NGAL, TNF-alpha and CCL2, and elevated plasma creatinine levels.

After a heart attack in normal mice, leukocyte immune cells in the spleen produce SPMs. However, in the ALX/FPR2-null mice, the researchers found lower levels of SPMs in the heart and the spleen after heart attack, indicative of non-resolving inflammation. Halade says this suggested impaired cross-talk between the injured heart and splenic leukocytes, a cross-talk that is required for the resolution of inflammation. In addition to the lower levels of SPMs, the ALX/FPR2-null mice showed dysregulation of several immune responsive enzymes -- lower levels of LOX enzymes and increased levels of the pro-inflammatory COX-1 and COX-2 enzymes.

Finally, the ALX/FPR2-null mice showed impairment of activated macrophage cells to phagocytose -- that is, to "eat" infecting microbes or dead human cells, one of the macrophage's prime functions. After heart attack, the ALX/FPR2-null mice had increased numbers of neutrophils, the first phagocytic responders after heart injury, in both the spleen and the left ventricle of the heart. Also, there were reduced numbers of reparative macrophages in both the spleen and the heart.

Altogether, says Halade, an associate professor in the UAB Department of Medicine Division of Cardiovascular Disease, these findings demonstrate the integrative role of ALX/FPR2 as a primary target to manage cardiometabolic health, inflammation-resolution processes and cardiorenal syndrome in aging.

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Materials provided by University of Alabama at Birmingham. Note: Content may be edited for style and length.