These researchers are unlocking Renaissance beauty secrets

Art historian Erin Griffey is a bit of a beauty maven. “I’m one of those people who reads the backs of beauty products,” she says. That’s why, while working on a book about beauty culture in Renaissance Europe, Griffey experienced déjà vu.

She noticed that many ingredients in beauty recipes from the 16th to 18th centuries — compiled from books, cosmetic recipe collections, medical texts, health regimen manuscripts, herbals and pharmacopeias — also appear on modern beauty packaging. For instance, rosewater is used in modern skin-hydrating mists and sulfur is found in some over-the-counter acne creams.
Such similarities are clues to what Renaissance-era people used the products for and how the products worked. But they are not the whole story. That’s because the ancient recipes often also list bizarre or even dangerous ingredients, from bile acids and calves’ hooves to lead and the poisonous bryony plant. To get a better understanding, Griffey wanted to re-create the recipes. So she turned to her colleagues at the University of Auckland in New Zealand. Thus the Beautiful Chemistry Project was born.

The team started with what Griffey calls “sticky recipes” because they’re found in many sources throughout the Renaissance period: rosemary flowers in white wine, myrrh powder with egg white, and the velvety covering of newly grown deer antlers with bean flour.

The recipes tend to be vague and varied. So chemist Michel Nieuwoudt and her team experiment with the measurements and procedures while Griffey searches various sources for more clues to ingredient types and ratios.

“We knew we could not re-create it exactly as is,” Griffey says of the recipe for rosemary flowers in white wine. “We do not have access to the rosemary plants that grew 500 years ago or the wines and whatever their chemical makeup was.” But this legwork “enabled us to get closer to an approximation.”

Nieuwoudt and her team boiled rosemary flowers in round-bottom flasks each filled with a different solution: sweet white wine, dry white wine, ethanol in water or aqua vitae. Once the researchers filtered out the flowers and analyzed the resulting mixtures using gas chromatography and mass spectrometry, they found chemical compounds that are common in today’s skin care products, including soothing camphor, eucalyptol and the fragrant alcohol linalool (SN: 7/22/02).

The Renaissance-era recipe stated the potion would “make the face fair.” Nieuwoudt’s findings suggest how: by toning and moisturizing skin.
The team has also made progress on unlocking the secrets of myrrh powder and egg whites. Experiments suggest that myrrh draws out proteins from egg whites and the egg whites extract resins, sugars and volatiles from the myrrh. That results in a serumlike product that has antiseptic and anti-inflammatory properties and probably stimulates collagen growth, Nieuwoudt says. “It seems there’s a synergy between all of these different ingredients, and this is why it works.”

As for what deer velvet and bean flour may have been used for, the researchers are still teasing out results. And they have yet to tackle recipes with dangerous ingredients.

Eventually, the researchers hope to perfect their re-creations and bring the products to drug store shelves — minus, of course, any unsafe ingredients. “I think people will want to go back to something that is natural, and it’s also appealing for people to think they’re using Renaissance products,” Nieuwoudt says. Until then, the beauty for the researchers lies in “digging [the recipes] out and understanding them.”

50 years ago, scientists hoped freezing donor organs would boost transplants

If whole organs could be frozen and stored … surgeons would be able to perform far more transplants…. For all their efforts, though, cryobiologists (biologists who study the effects of cold on life) have not been very successful with organ freezing…. Nobody to date has cooled whole mammalian hearts any lower [than −20° Celsius] or longer [than six hours] and revived them.

Scientists still struggle to keep donor hearts on ice for longer than six hours, but it is now possible to store a different organ — the liver — at below-freezing temperatures for more than a day. The challenge has been figuring out how to stop ice from crystallizing and damaging cells. In 2019, scientists reported successfully warming up several human livers after supercooling them for 27 hours (SN: 10/12/19 & 10/26/19, p. 10). This and other preservation methods such as freezing at high pressures or thawing using nanoparticles aren’t yet ready for the operating room, but they have the potential to keep thousands of lifesaving organs from going to waste each year.

COVID-19 infections can rebound for some people. It’s unclear why

For some people, including President Joe Biden and National Institute of Allergy and Infectious Diseases director Anthony Fauci, the relief of vanishing COVID-19 symptoms and a negative test is fleeting. Biden, Fauci and many others have seen their tests turn positive again or have unwelcome symptoms return after taking a five-day course of the antiviral Paxlovid. Other people, including my husband, have had their infections rebound even without taking the drug.

Multiple studies have described cases of “Paxlovid rebound” after treatment. In one, seven Paxlovid-treated patients had the virus rebound to high levels after treatment ended, and symptoms returned for six of them, virologist Jonathan Li and colleagues reported in June in Clinical Infectious Diseases. Samples from three patients even carried infectious virus, a clue that some people who rebound might infect others. Another study that has yet to be peer-reviewed by other researchers found that fewer than 6 percent of people in the study who’d been prescribed Paxlovid had rebound infections in the month after finishing treatment.
It’s unclear why Paxlovid rebound happens, says Li, of Brigham and Women’s Hospital and Harvard Medical School. Studies show that people given the drug still develop a strong immune response to the virus after five days of treatment. “I think what’s happening in that situation is that you’ve got virus replication that’s been inhibited. All of a sudden, the drug has disappeared and the virus has a momentary opportunity to replicate. And it replicates to high levels,” Li says. But by then, the immune system has learned to fend off the coronavirus. If the recently trained immune cells encounter newly made viruses and set off alarm bells, symptoms may briefly come back.

Some people might not want to take the drug because they’re worried about rebound, Li says. But Paxlovid itself probably isn’t the cause. The drug’s not failing. It is still highly effective in preventing severe disease. “I would not hesitate to give my patients Paxlovid,” Li says. “I do tell them to be on the lookout for rebounding symptoms. But it doesn’t dissuade me in terms of prescribing it.”

Fauci took another course of Paxlovid in the wake of his rebound. The U.S. Food and Drug Administration says that there’s no evidence that 10 days of treatment is any more effective than five days, or that patients need a repeat. But, researchers are testing whether taking the drug for a longer period of time might prevent rebound.

Rebounding COVID-19 isn’t limited to patients who take Paxlovid. Li recalls that even in the early days of the pandemic, some patients would come to him in the hospital saying that they’d started to feel better but got worse again. It’s hard to know how to interpret such anecdotal reports, he says. Researchers are still learning what an untreated viral infection can look like in the body. While the virus’s (hopefully) brief invasion may appear straightforward on average — with virus levels in the body increasing to a peak before slowly declining as the person recovers — not everyone follows that pattern.
My husband got COVID-19 two months ago. His symptoms lasted about a week, and he was delighted to see the line on his antigen test getting fainter. Even so, despite feeling perfectly healthy, the line was suddenly back at full strength almost immediately after he added his sample to a new test days later. He was frustrated and, as a social person, lamented having to stay isolated.

Studies show he’s not alone. When Li and colleagues studied the course of disease in COVID-19 clinical trial participants who received a placebo treatment, 1 in 8 people experienced a rebound, with symptoms coming back for 1 in 4 people. That rebound, however, typically lasted about a day, and few had both high viral loads and returning symptoms, the team reports in a preliminary study posted August 2 at that hasn’t yet been peer-reviewed by other scientists.

In this case, there’s no disappearing drug. Any returning symptoms without a positive test might be from something else such as allergies or a different respiratory virus, Li says. It’s also possible that the virus is replicating in different parts of the body at different times. Some tests might end up negative when the body eliminates virus from the throat, for example, but it’s still replicating at low levels in the nose.

That latter scenario may have happened with my husband. In a confusing twist, he tested negative on two saliva PCR tests while continuing to test positive on nasal antigen tests. A PCR test is far more sensitive, so we expected the opposite to happen. Since experts say to consider a positive antigen test as a sign you’re still contagious, he stayed isolated until he finally tested negative on an antigen test two weeks after his first symptoms appeared.

Luckily, he’s fully recovered now, and not at all eager for a repeat experience. That means we’re both still masking in public spaces and taking other precautions. We know we’re not done with this pandemic.