Researchers Identify Microbes That Help Plants Thwart Parasite

Sorghum crops in sub-Saharan Africa suffer heavy losses from the parasitic plant witchweed (Striga hermonthica). A new study shows how soil microbes can help protect sorghum from this pest and could be the basis for a soil probiotic treatment.
Photo Credit: Sabine

Bacteria that could help one of Africa’s staple crops resist a major pest have been identified by researchers at the University of California, Davis. Their findings, published in Cell Reports, could improve yields of sorghum, a mainstay of food and drink in West and East African countries.

About 20 percent of Africa’s sorghum crop is lost due to witchweed (Striga hermonthica), a parasitic plant that steals nutrients and water by latching onto the plant’s roots.

In a new study, UC Davis researchers show that soil microbes induce changes in sorghum roots that make the plant more resistant to infection by witchweed. They identified specific strains of bacteria that trigger these resistance traits and could be applied as a soil “probiotic” to improve sorghum yields in future.

“These microbes have great promise as soil additives that can help farmers grow sorghum successfully in sub-Saharan Africa,” said Siobhan Brady, a professor in the Department of Plant Biology and Genome Center and a senior author on the paper. 

Scientists propose a new way to search for dark matter

(Left) The new dark matter detection proposal looks for frequent interactions between nuclei in a detector and low-energy dark matter that may be present in and around Earth. (Right) A conventional direct detection experiment looks for occasional recoils from dark matter scattering.
Image Credit: Anirban Das, Noah Kurinsky and Rebecca Leane

Ever since its discovery, dark matter has remained invisible to scientists, despite the launch of multiple ultra-sensitive particle detector experiments around the world over several decades. 

Now, physicists at the Department of Energy’s (DOE) SLAC National Accelerator Laboratory are proposing a new way to look for dark matter using quantum devices, which might be naturally tuned to detect what researchers call thermalized dark matter.

Most dark matter experiments hunt for galactic dark matter, which rockets into Earth directly from space, but another kind might have been hanging around Earth for years, said SLAC physicist Rebecca Leane, who was an author on the new study. 

“Dark matter goes into the Earth, bounces around a lot, and eventually just gets trapped by the gravitational field of the Earth,” Leane said, bringing it into an equilibrium scientists refer to as thermalized. Over time, this thermalized dark matter builds up to a higher density than the few loose, galactic particles, meaning that it could be more likely to hit a detector. Unfortunately, thermalized dark matter moves much more slowly than galactic dark matter, meaning it would impart far less energy than galactic dark matter – likely too little for traditional detectors to see.

New machine to enhance understanding of nuclear weapons’ behavior

Bob Webster, deputy Laboratory director for Weapons (far right); Mike Furlanetto, Scorpius Advanced Sources and Detection project director (center); and Geoffrey Zehnder, project engineer (far left); discuss the prototype module Lab employees constructed for Scorpius' first accelerator cells and modules.
Photo Credit: Courtesy of Los Alamos National Laboratory

On March 7, assembly began at Los Alamos National Laboratory on a groundbreaking machine that will allow scientists to use real plutonium in experiments while studying the conditions immediately before the nuclear phase of a weapon's functioning. The machine will prove instrumental in the Laboratory's stockpile stewardship mission, which ensures the safety, security and reliability of the nation's nuclear weapons through computational tools and engineering test facilities, rather than underground testing.

Although the plutonium used will never reach criticality — the condition that forms a self-sustaining nuclear reaction — the tests performed as part of the Scorpius Advanced Sources and Detection (ASD) project will provide essential knowledge about how the key element in nuclear weapons behaves.

The components being built will be the first two accelerator cell modules for Scorpius.

"This means we have officially started building, and I am so looking forward to seeing this experiment in my lifetime," said Bob Webster, deputy Laboratory director for Weapons.

New Genetic Analysis Tool Tracks Risks Tied to CRISPR Edits

UC San Diego researchers have created a new system that reveals specific categories of potentially risky mutations resulting from CRISPR edits. This high magnification image reveals CRISPR-based DNA transcription of the homothorax gene in fruit fly embryos.
Image Credit: Bier Lab, UC San Diego

Since its breakthrough development more than a decade ago, CRISPR has revolutionized DNA editing across a broad range of fields. Now scientists are applying the technology’s immense potential to human health and disease, targeting new therapies for an array of disorders spanning cancers, blood conditions and diabetes.

In some designed treatments, patients are injected with CRISPR-treated cells or with packaged CRISPR components with a goal of repairing diseased cells with precision gene edits. Yet, while CRISPR has shown immense promise as a next-generation therapeutic tool, the technology’s edits are still imperfect. CRISPR-based gene therapies can cause unintended but harmful “bystander” edits to parts of the genome, at times leading to new cancers or other diseases.

Next-generation solutions are needed to help scientists unravel the complex biological dynamics behind both on- and off-target CRISPR edits. But the landscape for such novel tools is daunting, since intricate bodily tissues feature thousands of different cell types and CRISPR edits can depend on many different biological pathways.

Researchers a step closer to a cure for HIV

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

A new study involving University of Bristol researchers has shown a virus-like particle (HLP) can effectively 'shock and kill' the latent HIV reservoir.

By 2030, the World Health Organization (WHO), the Global Fund and UNAIDS are hoping to end the human immunodeficiency virus (HIV) and AIDS epidemic. An international team of researchers led by Professor Eric Arts from the Schulich School of Medicine & Dentistry, Canada, and Dr Jamie Mann, Senior Lecturer at the University of Bristol, has brought us another step closer to meeting this goal, by finding an effective and affordable targeted treatment strategy for an HIV cure. 

In a first, the study published in Emerging Microbes and Infections demonstrated the team's patented therapeutic candidate. The HIV-virus-like-particle (HLP), is 100 times more effective than other candidate HIV cure therapeutics for people living with chronic HIV on combined antiretroviral therapy (cART). If successful in clinical trials, HLP could be used by millions of people living around the world to free them of HIV. This study was done using blood samples from people living with chronic HIV. 

HLPs are dead HIV particles hosting a comprehensive set of HIV proteins that increase immune responses without infecting a person. When compared with other potential cure approaches, HLP is an affordable biotherapeutic and can be administered by intramuscular injection – similar to the seasonal flu vaccine. 

Two-Way Cell-based Treatment Repairs Muscle After Rotator Cuff Injury

A combination of mobilizing agent, designed to “push” pro-healing cells into the blood, and SDF-1a, designed to “pull” the cells into the injury site, leads to an increase in muscle regeneration following a rotator cuff tear. Muscle regeneration was characterized based on the number of centrally located nuclei (marked with the white arrows).
Image Credit: Courtesy of the researchers / Georgia Institute of Technology

A team of Georgia Tech researchers has introduced a new therapeutic system to offset the poor clinical outcomes often associated with common rotator cuff surgery.

It’s the kind of surgery that makes headlines whenever a famous athlete is sidelined with a torn rotator cuff. Major League Baseball All-Star pitchers Clayton Kershaw and Justin Verlander, for example, both had rotator cuff surgeries and made successful comebacks.

For those of us who can’t throw baseballs 95 miles an hour, the rotator cuff may tear over time from repeated overhead motions (painters and carpenters, for instance). Or an injury can occur as we age and our body’s tissues naturally degenerate. And although rotator cuff injuries are common, they can be serious, leading to muscle degeneration after surgery.

Now, two professors from the Wallace H. Coulter Department of Biomedical Engineering, a joint department of Georgia Tech and Emory University, have addressed the problem with a novel cell-based dual treatment, which they describe in a study published recently in the journal Tissue Engineering.

Climate change will see Australia’s soil emit CO2 and add to global warming

Australian Outback
Photo Credit: Nathan March

New Curtin University research has shown the warming climate will turn Australia’s soil into a net emitter of carbon dioxide (CO2), unless action is taken.

Soil helps to keep the planet cool by absorbing carbon, however as the climate gets warmer its ability to retain carbon decreases — and in some instances can start to release some carbon back into the air.

A global research team — led by Professor Raphael Viscarra Rossel from Curtin’s School of Molecular and Life Sciences— predicted the changes in the amount of carbon in Australia’s soil between now and the year 2100.

To do so, the team ran simulations using three different paths for society: an eco-focused ‘sustainable’ scenario, a ‘middle-of-the-road’ scenario and another which predicted a continued reliance on ‘fossil-fueled development’.

It found Australian soil will be a net emitter and could account for 8.3 per cent of Australia’s total current emissions under the ‘sustainable’ scenario and more than 14 per cent by 2045 under the ‘middle-of-the-road’ and ‘fossil-fueled’ scenarios.

Study explores severe hurricanes and coral reef sponge recolonization

For the study, scuba divers collected small samples of the thin purple morphotype sponges 14 and 22 months after the two Category 5 hurricanes in St. Thomas.
Photo Credit: Karli Hollister

Named for its ropy-looking long branches, Aplysina cauliformis, a coral reef sponge, provides a critical 3D habitat for marine organisms and helps to stabilize the foundation of coral reefs. However, these upright branching sponges are highly susceptible to breaking during storms, which increases sponge fragmentation and contributes to population clonality and inbreeding.

Many sponges can survive severe damage and undergo frequent fragmentation, which is considered a mechanism for asexual reproduction. While fragmentation is a commonly utilized reproductive strategy in rope sponges, they also can reproduce sexually by producing larvae. How and whether they recolonize following extreme weather events is critical for the restoration and resilience of coral reef ecosystems.

Hurricanes Irma and Maria – both in 2017 – were two rapid succession storms that provided researchers from Florida Atlantic University’s Harriet L. Wilkes Honors College and Harbor Branch Oceanographic Institute, and collaborators from the University of the Virgin Islands, the University of Mississippi and the University of Alabama, with a unique opportunity to address a priority concern – the resilience of coral reef sponge populations after severe hurricanes. 

Gut microbiota and antibiotics: Missing puzzle piece discovered

3D model of the small ribonucleic acid MasB.
Image Credit: Alexander Westermann/HIRI

HIRI scientists have identified a small RNA that influences the sensitivity of the intestinal commensal Bacteroides thetaiotaomicron to certain antibiotics.

The intricacies of how intestinal bacteria adapt to their environment have yet to be fully explored. Researchers from the Helmholtz Institute for RNA-based Infection Research (HIRI) in Würzburg and the University of California, Berkeley, USA, have now successfully closed a gap in this knowledge: They have identified a small ribonucleic acid (sRNA) that affects the susceptibility of the gut commensal Bacteroides thetaiotaomicron to specific antibiotics. The findings, published today in the journal Nature Microbiology, could serve as the foundation for novel therapies addressing intestinal diseases and combating antibiotic resistance. 

The gut, a complex ecosystem of numerous microorganisms, plays a pivotal role in human well-being. Factors like dietary changes, medications, or bile salts can influence the microbiota, impacting health. Among the prevalent intestinal bacteria in humans are Bacteroides thetaiotaomicron. These gut microbes play a role in breaking down polysaccharides during digestion, contributing to human health. Yet they can also promote infections when the ecosystem is disbalanced, such as after antibiotic treatment. However, the molecular mechanisms enabling these gut microbes to adapt to their environment remain largely unknown.

New Study Reveals Who Was More Vulnerable to Post-COVID Syndrome in Early Phases of the Pandemic

Fatigue, malaise and difficulty breathing were associated with post-COVID syndrome, according to the new Nordic study.
Photo Credit: Kinga Howard

People with post-COVID syndrome (PCS) following the COVID-19 infection often suffer from intense fatigue and dyspnea. This is what emerges from a new Nordic study led by Umeå University and recently published in the BMJ Public Health journal. High blood pressure also appears to be a risk factor for PCS diagnosis, according to the study’s findings.

"These scientific results are an important step in better understanding PCS. By identifying key factors, we can improve diagnosis, adapt care and pave the way for research into more effective treatments," says Anne-Marie Fors Connolly, MD PhD, Assoc Prof, clinical researcher at Umeå University and the study's senior author.

The study analyzed data from over one million people in Sweden who tested positive for COVID-19 during the period from February 2020 to May 2021. Of these, 1.5 percent, just over 16,000 people, were diagnosed with PCS after the main COVID-19 infection. They were diagnosed in both outpatient and inpatient care, which provided large datasets for the researchers to examine the clinical footprint of PCS. The researchers conducted an in-depth study of PCS symptoms in individuals who required ongoing healthcare three months after the COVID-19 infection.