An ambitious study of people with Long Covid, the mysterious,
disabling symptoms that can trail a SARS-CoV-2 infection, has turned up a
host of abnormalities in their blood. The clues add to a body of
evidence hinting at drivers of the condition and potential treatments
worth testing. They also suggest that, as many scientists and patients
have suspected, Long Covid shares certain features with myalgic
encephalomyelitis/chronic fatigue syndrome (ME/CFS), another condition
thought to follow an infection.
The new study, posted as a preprint last week,
was modest in size, examining just 99 people with Long Covid. “But it
went very deep, it went into granular aspects of the T cells, the
antibody response,” says Eric Topol, director of the Scripps Research
Translational Institute, who was not involved in the work. “This is
exploratory, but it’s the foundation for much bigger studies.”
The Long Covid patients, most of them struggling with intense
fatigue, brain fog, and other symptoms, had low levels of cortisol, a
stress hormone that helps the body control inflammation, glucose, sleep
cycles, and more. Features of their T cells indicated their immune
system was battling unidentified invaders, perhaps a reservoir of
SARS-CoV-2 or a reactivated pathogen such as Epstein-Barr virus.
Other groups studying Long Covid patients have reported similar results this year, including in a January Cell paper that documented low cortisol in those with long-lived respiratory symptoms,
and reactivation of viruses in patients with neurological issues.
Collectively, these data “make me think about what other drugs we can
test,” such as virus-directed antibodies or targeted anti-inflammatories
to tame the immune system, says Emma Wall at University College London
and the Francis Crick Institute, who co-leads a large trial of potential
Long Covid therapies. …
Sand on Earth is continuously being created by the slow erosion of
rocks. But on Mars, violent asteroid impacts may play an important role
in making new sand.
As much as a quarter of Martian sand is composed of spherical bits of
glass forged in the intense heat of impacts, a new study shows. Since
windblown sand sculpts the Martian landscape, this discovery reveals how
asteroid impacts contribute to shaping Mars,
even long after the collisions occur, Purdue University planetary
scientist Briony Horgan and colleagues suggest. The team will present
their results August 18 at the 85th Annual Meeting of the Meteoritical
Society in Glasgow, Scotland.
Using data collected by spacecraft orbiting Mars, Horgan and
collaborators looked at different wavelengths of visible and infrared
light reflected from the planet’s surface to determine the minerals
present in Martian sand. The team found signatures of glass all over the
planet, particularly at higher latitudes.
One explanation for all that glass is volcanic eruptions, which are
known to produce glass when magma mixes with water. But the most
glass-rich swath of Mars — the planet’s northern plains — is
conspicuously bereft of volcanoes, the researchers note. That rules out
volcanic eruptions as the culprit in that location and instead suggests
that far more cataclysmic events — asteroid impacts — might be involved. …
