“May you live in interesting times” is a strange curse often misattributed to an ancient Chinese saying. This time three years ago, widespread wildfires and dawning awareness of a new, contagious virus seemed to signal that the human species as a whole–all eight billion of us–had entered an entirely new era of “interesting times.”
This past week has laid to rest any expectation that 2023 would herald the advent of less interesting times. For one thing, it appears that the earth–at least its inner core–might actually have stood still. To make things more interesting still, just two weeks shy of Valentine’s Day, scientists have challenged one of our most widely-held beliefs about the chemistry of love and affection.
Sterile fetuses, a new “neuro-chip,” and some sobering news about lead exposure are all in this week’s headlines, proving that we still live in mighty interesting times.
Oregon Lead Poisoning Traced to Singaporean Eczema Cream
Lead exposure is unequivocally bad. There is no “safe” level of lead, and the human body has no way to rid itself of this heavy metal on its own. Over time, lead can cause irreversible neurological damage and cognitive impairment.
Parents are cautioned to watch for lead in plumbing (the Latin root of plumbing, plumbum, literally means lead–Ancient Roman plumbing systems were made of this heavy metal), and in vintage paints on toys and dishware. Most of us don’t expect to have to apply the same caution to infant care products.
Oregon Health Authority (OHA) recently discovered, however, that an over-the-counter cream for treating childhood eczema contained twice as much lead as lead paint. Public health authorities discovered the hazard after two different babies–one in Washington County and the other in Multnomah County–tested positive for high levels of lead.
In both cases, the culprit turned out to be an eczema cream called Diep Bao which is widely marketed in Singapore and Vietnam. Oregon Public Health officials have requested that all tubes of Diep Bao be turned over to the OHA. According to Ryan Barker, program coordinator of the Lead Poisoning Prevention Program at the Oregon Health Authority, halting sales of Diep Bao will be challenging because the product is marketed and sold almost solely online.
Oregon parents who want to turn in tubes of Diep Bao or seek testing for their children are encouraged to contact the Multnomah County lead line at 503-988-4000 or email email@example.com.
This alarming development underscores the importance of using only dermatologist-tested, peer-reviewed products for treating eczema. Only the best eczema cream will do.
The Day the Earth Stood Still?
More intriguing still was news that it might reverse direction. What does it mean, lay people were asking? Is the earth’s polarity about to reverse? Is North the new South? Is up the new down?
As it happens, the inner core did not stop moving last week; to the contrary, a pioneering study published in Nature asserted that the inner core had been slowing down since around 2009 and had finally synchronized its speed with the surface.
Scientists are not in agreement about this. The core never really stops moving at all–it just moves more or less slowly in relation to the Earth’s mantle. Even before last week, there was no scientific consensus about the speed of the inner core’s rotation, nor whether or not this speed varies.
The earth’s inner core is a layer of molten iron–and some nickel–some 3200 miles beneath us. This extremely hot layer (its temperature is estimated to be between 9,000 and 13,000 degrees Fahrenheit) is roughly the size of Mars. The speed and direction of the inner core’s rotation are estimated by measuring how fast the seismic waves of earthquakes reach the core.
In 1996, scientists discovered that the time it takes for seismic waves to reach the core seems to vary over time, which led them to hypothesize that the core spins at a different rate from the earth’s surface; since then, changes in the core’s spin have been believed to change every 70 years or so. The study published last week suggests that these changes occur at shorter intervals.
Hrvoje Tkalcic, a geophysicist at the Australian National University, assures us that the recent discoveries are nothing to be concerned about. “The inner core doesn’t come to a full stop,” Tkalcic says. “Nothing cataclysmic is happening.”
For now, the world continues to turn, and we can still trust our compass needles.
Irish Microbiologists Say Babies Are Born Without a Native Microbiome
Assumptions are being challenged in all areas of science this week. For years, biologists have believed that infants are colonized by bacteria while still in the womb. Researchers from the University College Cork (UCC) in Ireland published a study in Nature last week disputing that claim.
Previous studies seemed to indicate that fetuses acquired bacteria from the placenta and amniotic fluid prior to birth. The UCC study says that this belief was based upon contamination of samples taken from amniotic fluid and placental tissue samples, The researchers in Cork unanimously agree that this contamination occurs.during vaginal delivery, medical procedures, or in the lab.
A healthy fetus, according to the report, is completely uncolonized by bacteria–sterile, in other words. This has significant implications for our understanding of infant immune-system development.
The UCC experts say that future studies should focus upon mothers’ microbiomes and those of their newborns, as well as how microbial metabolites passed through the placenta prepare a fetus in a sterile environment for life in a world teeming with microbes.
Bacterial colonization occurs during the birth process and in the postnatal period, the study’s authors say; as such, any research into therapeutic manipulation of the microbiome should be focused upon those periods.
The study authors also offer guidance to researchers hoping to avoid the kinds of contamination that skewed previous studies.
Is Oxytocin Really the “Love Hormone?”
We might well ask ourselves this week–is nothing sacred? For decades, scientists have believed that oxytocin, a neurotransmitter released during pregnancy, childbirth, and bonding is critical to the development of social and romantic relationships. Just in time for Valentine’s Day, researchers studying the monogamous prairie vole are telling us that this isn’t the case.
Prairie voles mate for life and are monogamous. Unlike most vole species, the prairie vole has a complex social network. Prairie voles show a distinct preference for their mates and members of their social group. For forty years, it was thought that oxytocin, the so-called “love hormone,” played the leading role in the development of these bonds. Because oxytocin seems to play a similar role in human bonding, prairie voles have been studied as a model of how social behavior evolves.
A University of California, San Francisco study published last week in the journal Neuron charts how gene editing challenged assumptions about the importance of oxytocin in pair-bonding. Using CRISPR technology, the study authors used genetic engineering to target the oxytocin receptors of embryonic prairie voles, basically “turning off” the receptors. As a result, the embryos were born without any exposure to oxytocin signaling.
The researchers had expected the suppression of oxytocin receptors to inhibit the voles’ ability to form social bonds or pair-bonds. The voles surprised them by continuing to pair-bond monogamously.
In prior studies, oxytocin receptors were chemically suppressed in adult prairie voles, and it was hypothesized that they continued to form pair-bonds because of their previous exposure to oxytocin. The voles in the UC San Francisco study, though, bonded without any previous exposure to the hormone. The study was replicated by researchers at Emory University with the same results.
The researchers involved in the study say that this doesn’t mean oxytocin isn’t an important part of social bonding–it rather suggests that the mechanisms of social bonding are so critical to the prairie voles’ survival that there is a fail-safe ensuring against a “single point of failure.”
The researchers still maintain that oxytocin plays a role in social bonding–the precise role, however, now seems less clear, and the door has been opened to research how other hormones, such as vasopressin, influence social behaviors and pair-bonding.
Development of Neuro-chip Offers Hope for Management of Neurodegenerative Disease
Neurodegenerative disease can have profound, even devastating effects on those who suffer from them. Diseases such as Parkinson’s defy efforts to manage symptoms and frequently cause disability.. Technology developed by researchers at Ecole Polytechnique Fédérale de Lausanne in Switzerland could one day help people who suffer from these diseases–with a combination of artificial intelligence and an implanted microchip.
Mahsa Shoaran of the Integrated Neurotechnologies Laboratory in the School of Engineering and Stéphanie Lacour of the Laboratory for Soft Bioelectronic Interfaces partnered to develop NeuralTree, an implantable chip that works in real time to monitor a wide array of biomarkers to accurately predict symptoms and respond to alleviate them.
Shoaran says that NeuroTree’s design allows it to function with greater accuracy and versatility than previous chip-based symptoms-management implants. NeuralTree works with 256 input channels–previous devices used only 32. The ultra-efficient NeuralTree is a tiny 3.48 square millimeters.
NeuroTree was “trained” with datasets from both epilepsy and Parkinson's disease patients. It accurately recognized and classified neural signals from both disorders.
Shoaran sees interfaces such as NeuroTree playing a key role in the future treatment of neurological disorders.
"Eventually, we can use neural interfaces for many different disorders, and we need algorithmic ideas and advances in chip design to make this happen,’ she says.
She says the work is “very interdisciplinary,” and requires a high degree of collaboration between machine learning, data scientists, and medical researchers.
As you can see from this week’s news, we continue to live in interesting times–but that isn’t such a bad thing. The beauty of science is that it is never “done.” The unexpected never closes doors–it simply opens up new paths of knowledge. Our understanding of infant microbiomes might have been based upon erroneous beliefs, but understanding that allows us to approach future research with greater precision. While prairie voles might have seemingly knocked oxytocin down a few pegs, they’ve given us a new lens on social behaviors. Research on the earth’s core demonstrates that the world keeps turning, regardless of surprises.
Take care of yourselves as we slide into February. Make sure that all personal-care items you use, including eczema creams, are vetted by reliable research and backed by experts.