Researchers analyzed antibody tests conducted on more than 500 subjects in patient care settings. They found that people who had COVID, including those with mild symptoms, produced antibodies.

“For a long time, people were very worried that people with mild COVID did not make immune responses,” says Charles Schuler, M.D., a clinical assistant professor of allergy and immunology at Michigan Medicine. “This should give people confidence that the tests that are available to them aren’t just random number generators. They’re actually giving them something useful.”

The findings also indicate that rapid screens can predict infection with nearly the same precision as antibody tests conducted in a lab. Schuler, who led the research team, says the results could prove very useful for providers.

“I was actually surprised at how well some of these tests did because it’s a very different experiment,” Schuler says. “[If you have] a patient at a clinic that does not have a lab on site, we can find out if you had COVID before and we can do it now and we can do it at low cost.”

The team examined lateral flow assays, which Schuler describes as modern litmus tests: A drop of blood or serum is placed on filter paper that changes color to indicate whether antibodies are present.

Researchers then compared three rapid screens taken by finger pricks or blood draws in point-of-care settings to serology tests assessed in a lab. They examined data from 512 patients, of which 104 had a history of COVID-19 and a positive PCR test.

Despite some false positives, two rapid tests agreed with positive lab results between 93 and 97 percent of the time. Both tests outperformed the third brand, which lost its FDA emergency use authorization during the trial.

“I think the FDA has done a nice job regulating bad tests out of the market,” Schuler says. “These are still accurate in a point-of-care setting…[so], you’ve got a test that can be taken to different parts of the world and can be done without the need for a higher-complexity lab setting.”

American vaccination is quickly ramping up — nearly 30 percent of the population received at least one dose as of March 30, according to the Centers for Disease Control and Prevention. But in places where immunization lags, Schuler says these point-of-care antibody tests could help determine who is prioritized.

“It’s important to vaccinate everyone,” he says. “But, if you can direct vaccines to people, in particular, who may be totally unprotected, something like this would be useful. I do think more data is needed to say that from a policy perspective.”

The study population is limited, raising some questions about how the data can be generalized. Almost 90 percent of test subjects are health care workers, many providing direct care for COVID-19 patients.

However, Schuler’s team will continue evaluating the subjects with a new focus. Some recent studies indicate antibodies may persist and offer protection for several months. Schuler hopes to make that answer more concrete.

“This is a down payment on, hopefully, a lot of great future data” he says. “While antibodies may or may not tell you how immunity happens, they might tell you about reinfection risk. That is the functional clinical significance that we need to know as soon as possible.”

Disclosures: The study was partially funded through two companies, Healgen Scientific and Access Bio Inc. Tests, which are normally sold, were provided at no cost by both companies, as well as Autobio Diagnostics Co. Ltd. Schuler, along with two other U-M physicians, received salary support from an institutional COVID-19 grant.

Named for their six-sided crystal structure, hexagonal diamonds have been found at some meteorite impact sites, and others have been made briefly in labs, but these were either too small or had too short of an existence to be measured.

Now scientists at Washington State University’s Institute for Shock Physics created hexagonal diamonds large enough to measure their stiffness using sound waves. Their findings are detailed in a recent paper in Physical Review B.

“Diamond is a very unique material,” said Yogendra Gupta, director of the Institute for Shock Physics and corresponding author on the study. “It is not only the strongest — it has beautiful optical properties and a very high thermal conductivity. Now we have made the hexagonal form of diamond, produced under shock compression experiments, that is significantly stiffer and stronger than regular gem diamonds.”

Researchers have long wanted to create a material stronger than natural diamonds, which could have a variety of uses in industry. While many theorized that hexagonal diamonds would be stronger, the WSU study provides the first experimental evidence that they are.

Lead author Travis Volz, now a post-doctoral researcher at Lawrence Livermore National Laboratory, focused his dissertation work at WSU on the creation of hexagonal diamonds from graphite. For this study, Volz and Gupta used gunpowder and compressed gas to propel small graphite disks about the size of a dime at a speed of around 15,000 miles per hour onto a transparent material. The impact produced shockwaves in the disks that very rapidly transformed them into hexagonal diamonds.

Immediately after impact the researchers produced a small sound wave and used lasers to measure its movement through the diamond. Sound moves faster through stiffer material. Previously sound moved fastest through cubic diamond; in the lab-created hexagonal diamonds it moved faster.

Each process happened in several billionths of a second, or nanoseconds, but the researchers were able to make the stiffness measurements before the high velocity impact destroyed the diamond.

Stiffness is the ability of a material to resist deformation under a force or pressure — for instance, a rock is stiffer than rubber as rubber will bend when pressed. Hardness is the resistance to scratching or other surface deformations.

Generally stiffer materials are also harder, said Volz. While the researchers weren’t able to scratch the diamonds to test hardness directly, by measuring the diamonds’ stiffness, they can make inferences about their hardness.

If the science advances to the point where lab-made hexagonal diamonds can be created and recovered, they could have a range of uses.

“Hard materials are useful for machining capabilities,” said Volz. “Diamond has been used for a long time in drill bits, for example. Since we found that the hexagonal diamond is likely harder than the cubic diamond, it could be a superior alternative for machining, drilling or any type of application where the cubic diamond is used.”

While the industrial advantages are clear, Gupta said it is still possible hexagonal diamonds could one day be used on engagement rings. Currently lab-made cubic diamonds have less value compared to their natural peers, but hexagonal diamonds would likely be more novel.

“If someday we can produce them and polish them, I think they’d be more in-demand than cubic diamonds,” said Gupta. “If somebody said to you, ‘look, I’m going to give you the choice of two diamonds: one is lot more rare than the other one.’ Which one would you pick?”

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Materials provided by Washington State University. Original written by Sara Zaske. Note: Content may be edited for style and length.

Cardiometabolic health risk factors include the metabolic syndrome, a cluster of disorders such as excess fat around the waist, insulin resistance and high blood pressure. Presence of the metabolic syndrome may increase the risk of developing heart disease, stroke and Type 2 diabetes.

Researchers noted it has been unclear whether adherence to both the U.S. Department of Health and Human Services’ 2018 Physical Activity Guidelines for Americans and their 2015-2020 Dietary Guidelines for Americans — as opposed to only one of the two — in midlife confers the most favorable cardiometabolic health outcomes later in life. The physical activity guidelines recommend that adults achieve at least 150 minutes of moderate or 75 minutes of vigorous physical activity per week, such as walking or swimming. The dietary guidelines, which were updated in January 2021, offer suggestions for healthy eating patterns, nutritional targets and dietary limits.

In an analysis of data from participants of the Framingham Heart Study, which began more than 70 years ago in Framingham, Massachusetts, investigators examined data from 2,379 adults ages 18 and older and their adherence to the two guidelines. They observed that meeting a combination of the two recommendations during midlife was associated with lower odds of metabolic syndrome and developing serious health conditions as participants aged in their senior years in 2016-2019 examinations.

“Health care professionals could use these findings to further promote and emphasize to their patients the benefits of a healthy diet and a regular exercise schedule to avoid the development of numerous chronic health conditions in the present and in later life,” said corresponding author Vanessa Xanthakis, Ph.D., FAHA, assistant professor of medicine and biostatistics in the Section of Preventive Medicine and Epidemiology at Boston University School of Medicine in Boston. “The earlier people make these lifestyle changes, the more likely they will be to lower their risk of cardiovascular-associated diseases later in life.”

Study participants were selected from the third generation of the Framingham Heart Study. Participants (average age 47, 54% women) were examined between 2008 and 2011. Researchers evaluated physical activity using a specialized device known as an omnidirectional accelerometer. The device, which tracks sedentary and physical activity, was worn on the participant’s hip for eight days. Researchers also collected dietary information from food frequency questionnaires to measure the kinds and levels of food and nutrients consumed.

In this investigation, researchers observed that among all participants, 28% met recommendations of both the physical activity and dietary guidelines, while 47% achieved the recommendations in only one of the guidelines. Researchers also observed that:

• participants who followed the physical activity recommendations alone had 51% lower odds of metabolic syndrome;
• participants who adhered to the dietary guidelines alone had 33% lower odds; and
• participants who followed both guidelines had 65% lower odds of developing metabolic syndrome.

“It is noteworthy that we observed a dose-response association of adherence to diet and physical activity guidelines with risk of cardiometabolic disease later in life,” Xanthakis said. “Participants who met the physical activity guidelines had progressively lower risk of cardiometabolic disease as they increased adherence to the dietary guidelines.”

All study participants were white adults, therefore, the findings cannot be generalized to people in other racial or ethnic groups. Additional studies with a multiethnic participant sample are needed, researchers said.

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Materials provided by American Heart Association. Note: Content may be edited for style and length.

However, scientific understanding of just how these parts of the brain work is limited. Consequently, knowledge of how to improve challenges such as speech impediments or language acquisition is limited as well.

Using an ultra-lightweight, wireless implant, a University of Arizona team is researching songbirds — one of the few species that share humans’ ability to learn new vocalizations — to improve scientific understanding of human speech. A paper about their work was published today in the journal Nature Communications.

“Using new methods of antenna design and optimized electronics, we were able to shrink the devices dramatically compared to existing versions, to about a third of the size of a dime and as thin as a sheet of paper,” said lead author Jokubas Ausra, a biomedical engineering doctoral student in the Gutruf Lab, where the devices were created.

There are several ways the device can be used to study the link between brain behavior and vocalization. It can monitor the bird for slight temperature changes that indicate when a bird is most likely to sing. Using a technique called optogenetics, researchers can modulate neuron groups in the brain regions used for birdsong. In this study, the team found that remotely controlling specific neurons during birdsong using their unique device caused the song to change pitch.

“We are excited to expand the toolbox of neuroscientists and hope to enable many exciting studies that decipher the working principles of the brain,” said senior author Philipp Gutruf, assistant professor of biomedical engineering and Craig M. Berge Fellow in the UArizona College of Engineering.

The Gutruf Lab has developed other wireless lightweight devices used to monitor brain activity in rodents, but birds’ ability to move in 3D space represents an added challenge. This tiny device allows the birds to move without restriction — a breakthrough enabled by careful management of the energy sent wirelessly to the implant.

“Because of the small size and light weight, the birds can move freely and live permanently with the implant without affecting their behavior or health, which opens up many possibilities to study the basis for vocal communication,” said co-senior author Julie Miller, an assistant professor of neuroscience and speech, language and hearing sciences at UArizona.

The team’s next goal is to expand device capabilities to also record neuron activity. This could allow researchers to visualize brain activity during song learning and performance to gain a deeper understanding of the underlying brain mechanisms.

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Materials provided by University of Arizona College of Engineering. Note: Content may be edited for style and length.

“Being stuck at home was a blessing in disguise, as there were no experiments that could be done. We just had our computers and lots of time,” says Professor Paul Curmi, a structural biologist and molecular biophysicist with UNSW Sydney.

Prof. Curmi is referring to research published this month in Nature Communications that details the painstaking unravelling and reconstruction of a key protein in a single-celled, photosynthetic organism called a cryptophyte, a type of algae that evolved over a billion years ago.

Up until now, how cryptophytes acquired the proteins used to capture and funnel sunlight to be used by the cell had molecular biologists scratching their heads. They already knew that the protein was part of a sort of antenna that the organism used to convert sunlight into energy. They also knew that the cryptophyte had inherited some antenna components from its photosynthetic ancestors — red algae, and before that cyanobacteria, one of the earliest lifeforms on earth that are responsible for stromatolites.

But how the protein structures fit together in the cryptophyte’s own, novel antenna structure remained a mystery — until Prof. Curmi, PhD student Harry Rathbone and colleagues from University of Queensland and University of British Columbia pored over the electron microscope images of the antenna protein from a progenitor red algal organism made public by Chinese researchers in March 2020.

Unravelling the mystery meant the team could finally tell the story of how this protein had enabled these ancient single-celled organisms to thrive in the most inhospitable conditions — metres under water with very little direct sunlight to convert into energy.

Prof. Curmi says the major implications of the work are for evolutionary biology.

“We provide a direct link between two very different antenna systems and open the door for discovering exactly how one system evolved into a different system — where both appear to be very efficient in capturing light,” he says.

“Photosynthetic algae have many different antenna systems which have the property of being able to capture every available light photon and transferring it to a photosystem protein that converts the light energy to chemical energy.”

By working to understand the algal systems, the scientists hope to uncover the fundamental physical principles that underlie the exquisite photon efficiency of these photosynthetic systems. Prof. Curmi says these may one day have application in optical devices including solar energy systems.

EATING FOR TWO

To better appreciate the significance of the protein discovery, it helps to understand the very strange world of single-celled organisms which take the adage “you are what you eat” to a new level.

As study lead author, PhD student Harry Rathbone explains, when a single-celled organism swallows another, it can enter a relationship of endosymbiosis, where one organism lives inside the other and the two become inseparable.

“Often with algae, they’ll go and find some lunch — another alga — and they’ll decide not to digest it. They’ll keep it to do its bidding, essentially,” Mr Rathbone says. “And those new organisms can be swallowed by other organisms in the same way, sort of like a matryoshka doll.”

In fact, this is likely what happened when about one and a half billion years ago, a cyanobacterium was swallowed by another single-celled organism. The cyanobacteria already had a sophisticated antenna of proteins that trapped every photon of light. But instead of digesting the cyanobacterium, the host organism effectively stripped it for parts — retaining the antenna protein structure that the new organism — the red algae — used for energy.

And when another organism swallowed a red alga to become the first cryptophyte, it was a similar story. Except this time the antenna was brought to the other side of the membrane of the host organism and completely remoulded into new protein shapes that were equally as efficient at trapping sunlight photons.

EVOLUTION

As Prof. Curmi explains, these were the first tiny steps towards the evolution of modern plants and other photosynthetic organisms such as seaweeds.

“In going from cyanobacteria that are photosynthetic, to everything else on the planet that is photosynthetic, some ancient ancestor gobbled up a cyanobacteria which then became the cell’s chloroplast that converts sunlight into chemical energy.

“And the deal between the organisms is sort of like, I’ll keep you safe as long as you do photosynthesis and give me energy.”

One of the collaborators on this project, Dr Beverley Green, Professor Emerita with the University of British Columbia’s Department of Botany says Prof. Curmi was able to make the discovery by approaching the problem from a different angle.

“Paul’s novel approach was to search for ancestral proteins on the basis of shape rather than similarity in amino acid sequence,” she says.

“By searching the 3D structures of two red algal multi-protein complexes for segments of protein that folded in the same way as the cryptophyte protein, he was able to find the missing puzzle piece.”