HIV can persist for years in myeloid cells of people on antiretroviral therapy

HIV, the AIDS virus (yellow), infecting a human cell
Image Credit: National Cancer Institute

NIH-funded study confirms white blood cell subtype as HIV reservoir, suggests new target for cure efforts.

A subset of white blood cells, known as myeloid cells, can harbor HIV in people who have been virally suppressed for years on antiretroviral therapy, according to findings from a small study supported by the National Institutes of Health. In the study, researchers used a new quantitative method to show that HIV in specific myeloid cells—short-lived monocytes and longer-lived monocyte-derived macrophages—can be reactivated and infect new cells. The findings, published in Nature Microbiology, suggest that myeloid cells contribute to a long-lived HIV reservoir, making these cells an important but overlooked target in efforts to eradicate HIV.

“Our findings challenge the prevailing narrative that monocytes are too short-lived to be important in cure efforts,” said study author Rebecca Veenhuis, Ph.D., an assistant professor of molecular and comparative pathobiology and of neurology at Johns Hopkins University School of Medicine, Baltimore. “Yes, the cells are short-lived, but our follow-up data show that HIV can persist in monocytes over several years in people who are virally suppressed. The fact that we can detect HIV in these cells over such a long period suggests something is keeping the myeloid reservoir going.”

With fewer salmon to eat, Southern Resident killer whales spend less time in the San Juan Islands

killer whales
Photo Credit: Michelle Klampe

As a key food supply declines, the endangered population of Southern Resident killer whales, known to frequent the Salish Sea off the coasts of Washington and British Columbia, is spending far less time in that region, a new study shows.

The Salish Sea around the San Juan Islands has traditionally been a hotspot for the whales. The Southern Residents would spend the summer months feeding on Chinook salmon, much of which belonged to the Fraser River stock that passes through the islands on its way to spawning grounds upriver.

But 17 years of whale sighting data shows that as the Fraser River Chinook salmon population dropped, the time spent by the Southern Residents around the San Juan Islands also declined ­– by more than 75%, said Joshua Stewart, an assistant professor with Oregon State University’s Marine Mammal Institute and the study’s lead author.

The findings were just published in the journal Marine Mammal Science. Co-authors of the paper are Jane Cogan, an independent researcher in Friday Harbor, Washington; John Durban, a professor with MMI who is also affiliated with the nonprofit SeaLife Response, Rehabilitation and Research (SR3); Holly Fearnback of SR3; David Ellifrit, Mark Malleson and Ken Balcomb of the nonprofit Center for Whale Research; and Melisa Pinnow of San Juan Orcas, a website dedicated to identification of individual orcas.

Components of Cytoskeleton Strengthen Effect of Sex Hormones

Super-high-resolution microscopic image of a cell that has been exposed to the sex hormone dihydrotestosterone. The androgen receptor (violet) and actin (green) are visible in the cell nucleus. Both molecules are stained with fluorescent dyes and thus made visible. The individual structures made visible (right) are only 200 nanometers (200 millionths of a millimeter) small.
Image Credit: Julian Knerr/University of Freiburg

Researchers from Freiburg and Kiel discover that actin acts in the cell nucleus and is partly responsible for the expression of male sexual characteristics

Steroid hormones, to which belong sex hormones like estrogen or testosterone, are important signaling molecules and are responsible among other things for controlling female and male phenotypic sex differentiation. They act by binding to receptor molecules that switch on and off the activity of hormone-dependent genes. Researchers at the University of Freiburg and Kiel University Hospital have discovered that components of the cytoskeleton are critically involved in this process. The findings are relevant for the diagnosis of medical conditions and the study of diseases and cancers in which steroid hormones play important roles. The study was published in the renowned journal Nature.

The new research findings show that filamentous actin, a component of the cytoskeleton, interacts with the androgen receptor directly in the cell nucleus and strengthens its effect. The androgen receptor mediates the signals of sex hormones for male sex development but also promotes the progression of prostate cancer.

Giant planet atmospheres vary widely, JWST confirms

 A ‘hot Jupiter’ called HD 149026b, is about 3 times hotter than the rocky surface of Venus, the hottest planet in our solar system.
Illustration Credit: NASA/JPL-Caltech

Gas giants orbiting our sun show a clear pattern; the more massive the planet, the lower the percentage of “heavy” elements (anything other than hydrogen and helium) in the planet’s atmosphere. But out in the Galaxy, the atmospheric compositions of giant planets do not fit the solar system trend, an international team of astronomers has found.

Using NASA’s James Webb Space Telescope (JWST), the researchers discovered that the atmosphere of exoplanet HD149026b, a ‘hot Jupiter’ orbiting a star comparable to our sun, is super-abundant in the heavier elements carbon and oxygen – far above what scientists would expect for a planet of its mass. In addition, the diagnostic carbon-to-oxygen ratio of HD149026b, also known as “Smertrios,” is elevated relative to our solar system.

A ‘hot Jupiter’ called HD 149026b, is about 3 times hotter than the rocky surface of Venus, the hottest planet in our solar system.

These findings, published in “High atmospheric metal enrichment for a Saturn-mass planet,” in Nature on [March 27] are an important first step toward obtaining similar measurements for a large sample of exoplanets in order to search for statistical trends, the researchers said. They also provide insight into planet formation.

Beaver Fossil Named After Buc-ee’s

Matthew Brown (left) and Steve May with beaver skulls new and old in the vertebrate paleontology collections at the Jackson School of Geosciences. Brown, the director of the collections, holds a skull from a modern North American Beaver. May, a research associate, holds a skull from Anchitheriomys buceei, a new species of ancient beaver that he discovered in the collections and named.
Photo Credit: UT Jackson School of Geosciences.

A new species of ancient beaver that was rediscovered by researchers in The University of Texas Austin’s fossil collections has been named after Buc-ee’s, a Texas-based chain of popular travel centers known for its cartoon beaver mascot.

The beaver is called Anchitheriomys buceei, or “A. buceei” for short.

Steve May, a research associate at the UT Jackson School of Geosciences, said that the beaver’s Texas connection and a chance encounter with a Buc-ee’s billboard are what inspired the name.

May is the lead author of the paper that describes A. buceei, along with another, much smaller, species of fossil beaver. Published in the journal Palaeontologia Electronica, the paper provides an overview of beaver occurrences along the Texas Gulf Coast from 15 million to 22 million years ago based on bones and archival records in the UT collections.

While driving down a highway in 2020, May spotted a Buc-ee’s billboard that said “This is Beaver Country.” The phrase brought to mind the Texas beaver fossils he had been studying at UT’s Texas Vertebrate Paleontology Collections.

Understanding nitrogen metabolism could revolutionize TB treatment, finds study

Illustration Credit: Courtesy of University of Surrey

Development of new drugs to effectively target the bacterium that causes tuberculosis (TB) could be one step closer following an important discovery from the University of Surrey.

The Surrey study used a technology called fluxomics to reveal important information about how cells process nitrogen, which could help us better understand how harmful bacteria survive and cause disease. These findings have significant implications for studying the behavior and impact of pathogenic bacteria on human health.

In the most comprehensive study of its kind, the research team from Surrey conducted a study on the bacterium that causes tuberculosis, called Mycobacterium tuberculosis (Mtb). They wanted to understand how nitrogen is processed within Mtb cells, which is essential for the bacterium's survival. Surprisingly, previous studies had mostly examined the role of carbon in Mtb's survival, leaving the role of nitrogen poorly understood.

Earth’s first plants likely to have been branched, study finds

Selaginella
Photo Credit: Vicky Spencer

A new discovery by scientists at the University of Bristol changes ideas about the origin of branching in plants.

By studying the mechanisms responsible for branching, the team have determined what the first land plants are likely to have looked like millions of years ago. 

Despite fundamentally different patterns in growth, their research has identified a common mechanism for branching in vascular plants.

Dr Jill Harrison from Bristol’s School of Biological Sciences explained: “Diverse shapes abound in the dominant flowering plant group, and gardeners will be familiar with ‘pinching out’ plants’ shoot tips to stimulate side branch growth, leading to a bushier overall form.

“However, unlike flowering plants, other vascular plants branch by splitting the shoot apex into two during growth, a process known as ‘dichotomy’.

As an ancient vascular plant lineage that formed coal seams during the Carboniferous era, lycophytes preserve the ancestral pattern of dichotomous branching.

Surprise effect: Methane cools even as it heats

Annual mean near-surface air temperature response to methane, decomposed into (a) longwave and shortwave effects; (b) longwave effects only; and (c) shortwave effects only.
Full size Image
Illustration Credit: Robert Allen / University of California, Riverside

Most climate models do not yet account for a new UC Riverside discovery: methane traps a great deal of heat in Earth’s atmosphere, but also creates cooling clouds that offset 30% of the heat. 

Greenhouse gases like methane create a kind of blanket in the atmosphere, trapping heat from Earth’s surface, called longwave energy, and preventing it from radiating out into space. This makes the planet hotter. 

“A blanket doesn’t create heat, unless it’s electric. You feel warm because the blanket inhibits your body’s ability to send its heat into the air. This is the same concept,” explained Robert Allen, UCR assistant professor of Earth sciences.

In addition to absorbing longwave energy, it turns out methane also absorbs incoming energy from the sun, known as shortwave energy. “This should warm the planet,” said Allen, who led the research project. “But counterintuitively, the shortwave absorption encourages changes in clouds that have a slight cooling effect.”

Fish Will Help Scientists to Measure Levels of Radiation

Researchers' finding will supplement the radiation monitoring of rivers and lakes in the Southern Urals.
 Photo Credit: Rodion Narudinov

The method showed its effectiveness in radionuclide-contaminated waters of the South Urals

Otoliths are hearing and equilibrium maintenance organs of fish that do not contain living cells. They can be used as individual dosimeters for radiobiology and radioecology studies. This was discovered by a team of scientists from the Ural Federal University along with their colleagues from the Chelyabinsk State University and the Ural Scientific-Practical Center of Radiation Medicine.

When exposed to ionizing radiation, otolith hydroxyapatite crystals accumulate stable radicals. These radicals are proportional to the absorbed dose. Dosimetry using electron paramagnetic resonance (EPR) detects carbonate ions. As a result, the total radiation accumulated by the fish can be quantified.

The findings of the researchers will supplement the radiation monitoring of rivers and lakes in the Southern Urals, in particular, to detect the impact of radiation from strontium-90 radionuclides in the influence zone of the "Mayak" production association. Scientists concluded that EPR dosimetry in fish otoliths is a promising tool for external or comparable internal exposure.

Researchers develop electrolyte enabling high efficiency of safe, sustainable zinc batteries

Photo Credit: Courtesy of Oregon State University

Scientists led by an Oregon State University researcher have developed a new electrolyte that raises the efficiency of the zinc metal anode in zinc batteries to nearly 100%, a breakthrough on the way to an alternative to lithium-ion batteries for large-scale energy storage.

The research is part of an ongoing global quest for new battery chemistries able to store renewable solar and wind energy on the electric grid for use when the sun isn’t shining and the wind isn’t blowing.

Xiulei “David” Ji of the OSU College of Science and a collaboration that included HP Inc. and GROTTHUSS INC., an Oregon State spinout company, reported their findings in Nature Sustainability.

“The breakthrough represents a significant advancement toward making zinc metal batteries more accessible to consumers,” Ji said. “These batteries are essential for the installation of additional solar and wind farms. In addition, they offer a secure and efficient solution for home energy storage, as well as energy storage modules for communities that are vulnerable to natural disasters.”

A battery stores electricity in the form of chemical energy and through reactions converts it to electrical energy. There are many different types of batteries, but most of them work the same basic way and contain the same basic components.