Unconventional Approach to C. Diff

C. difficile bacteria seen through a scanning electron microscope and colored green.
Image Credit: Janice Carr via CDC

Clostridioides difficile (C. diff) intestinal infections can cause severe, debilitating diarrhea in patients who are hospitalized or on immunosuppressive therapies. The infections can be very hard to eradicate, roaring back when patients try to taper their antibiotics. Many people wind up on antibiotics for months and can become resistant to three or more of them.

“Often being on antibiotics isn’t sufficient,” explained Meenakshi Rao, Harvard Medical School assistant professor of pediatrics at Boston Children’s Hospital. “The infection can catalyze severe, runaway inflammation, especially in patients with inflammatory bowel disease.”

This inflammation, in turn, promotes C. diff colonization of intestinal tissue. And antibiotics themselves could be part of the problem.

“Once we attack C. diff with antibiotics, it disrupts the gut microbiome,” said Min Dong, HMS associate professor of surgery at Boston Children’s, whose lab studies bacterial toxins and how to combat them. “That creates an opportunity for severe, recurring infection, and it becomes a vicious cycle.”

Venus had Earth-like plate tectonics billions of years ago

Photo Credit: NASA/JPL

A new study found that Venus, a scorching wasteland of a planet according to scientists, may have once had tectonic plate movements similar to those believed to have occurred on early Earth, a new study found. The finding sets up tantalizing scenarios regarding the possibility of early life on Venus, its evolutionary past and the history of the solar system.

Writing in Nature Astronomy, a team of scientists led by Brown University researchers describes using atmospheric data from Venus and computer modeling to show that the composition of the planet’s current atmosphere and surface pressure would only have been possible as a result of an early form of plate tectonics, a process critical to life that involves multiple continental plates pushing, pulling and sliding beneath one another.

On Earth, this process intensified over billions of years, forming new continents and mountains, and leading to chemical reactions that stabilized the planet’s surface temperature, resulting in an environment more conducive to the development of life.

Fruit, nectar, bugs and blood: How bat teeth and jaws evolved for a diverse dinnertime

A side-view image of the skull of a greater spear-nosed bat, Phyllostomus hastatus, a noctilionoid species with an omnivorous diet.
Photo Credit: Sharlene Santana/University of Washington

They don’t know it, but Darwin’s finches changed the world. These closely related species — native to the Galapagos Islands — each sport a uniquely shaped beak that matches their preferred diet. Studying these birds helped Charles Darwin develop the theory of evolution by natural selection.

A group of bats has a similar — and more expansive — evolutionary story to tell. There are more than 200 species of noctilionoid bats, mostly in the American tropics. And despite being close relatives, their jaws evolved in wildly divergent shapes and sizes to exploit different food sources. A paper published in Nature Communications shows those adaptations include dramatic, but also consistent, modifications to tooth number, size, shape and position. For example, bats with short snouts lack certain teeth, presumably due to a lack of space. Species with longer jaws have room for more teeth — and, like humans, their total tooth complement is closer to what the ancestor of placental mammals had.

Breakthrough synthesis method improves solar cell stability

Jin Hou is a Rice University graduate student and lead author on a study published in Nature Synthesis. Photo Credit: Courtesy of Jin Hou

Solar cell efficiency has soared in recent years due to light-harvesting materials like halide perovskites, but the ability to produce them reliably at scale continues to be a challenge.

A process developed by Rice University chemical and biomolecular engineer Aditya Mohite and collaborators at Northwestern University, the University of Pennsylvania and the University of Rennes yields 2D perovskite-based semiconductor layers of ideal thickness and purity by controlling the temperature and duration of the crystallization process.

Known as kinetically controlled space confinement, the process could help improve the stability and reduce the cost of halide perovskite-based emerging technologies like optoelectronics and photovoltaics.

Unlocking Sugar to Generate Biofuels and Bioproducts

Chang-Jun Liu (left) and Nidhi Dwivedi (right) in the Brookhaven Lab greenhouse with rice plants like those used in this study.
Photo Credit: Courtesy of Brookhaven National Laboratory

Plant biologists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have engineered enzymes to modify grass plants so their biomass can be more efficiently converted into biofuels and other bioproducts. As described in a paper just published in Plant Biotechnology Journal, these enzymes modify molecules that make up plant cell walls to provide access to fuel-generating sugars normally locked within complex structures. 

“The concept of biomass to biofuel seems simple, but it is technically very difficult to release the sugars,” noted Chang-Jun Liu, a senior plant biologist at Brookhaven Lab who led the study.

Plant biomass is full of energy-rich complex sugar molecules generated from photosynthesis. Each plant cell is surrounded by a rigid cell wall made of sugars and a material called lignin that provides structural support. Reducing lignin to gain access to the sugars has been the focus of research aimed at using plants to generate fuels and other products commonly made from petroleum.

Endangered whales live in area earmarked for gas exploration

Risso's dolphins.
Photo Credit Leonidas Karantzas/Greenpeace

Endangered whales and dolphins live year-round in an area of the Mediterranean earmarked for oil and gas exploration, new research shows.

Various cetacean species are known to inhabit the Hellenic Trench off Greece in the summer, but until now little has been known about their winter whereabouts.

This lack of information has been used to justify seismic surveys (which may harm whales and dolphins) in winter.

The new study found that at least four species – including the regionally endangered sperm whale – live in the deep waters of the Hellenic Trench in both summer and winter.

The research was carried out in 2021-22 by the Greenpeace Research Laboratories, University of Exeter, Greenpeace Greece and the Pelagos Cetacean Research Institute.

“The Mediterranean is one of the busiest seas on the planet, and whales and dolphins are already threatened by ship strikes, overfishing, bycatch (accidental catching), pollution with chemicals and plastics, and climate change,” said Dr Kirsten Thompson.

Machine can quickly produce needed cells for cancer treatment

WSU researchers have developed a minifridge-sized bioreactor that is able to manufacture the cells, called T cells, at 95% of the maximum growth rate – about 30% faster than current technologies.
Photo Credit: Courtesy of Washington State University

A new tool to rapidly grow cancer-killing white blood cells could advance the availability of immunotherapy, a promising therapy which harnesses the power of the body’s immune response to target cancer cells.

Washington State University researchers have developed a minifridge-sized bioreactor that is able to manufacture the cells, called T cells, at 95% of the maximum growth rate – about 30% faster than current technologies. The researchers report on their work in the journal Biotechnology Progress. They developed it using T cells from cattle, developed by co-author Bill Davis of WSU’s Veterinary College, and anticipate it will perform similarly on human cells.

In 2022, there were over 1,400 different types of therapies using T cells in development, with seven approved by the FDA for a variety of cancer treatments. Use of the therapy, called chimeric antigen receptor T cell (CAR-T), is limited, however, because of the cost and time needed to grow T cells. Each infusion treatment for a cancer patient requires up to 250 million cells.

An unexpected link between 2 schizophrenia risk proteins

The study findings suggest that when the proteins don’t bind properly, signaling among neurons, illustrated above, becomes imbalanced, which can lead to related negative behavioral symptoms.
 Image Credit: T. Ahmed, A. Buonanno, National institute of Child Health and Human Development

The discovery of a physical interaction between two proteins in brain cells that can be traced in mice to control of movement, anxiety and memory could one day open the door to development of new schizophrenia treatment strategies.

The research group is the first to determine that the two proteins, both among the dozens of proteins related to risk for the development of schizophrenia, bind to each other under normal conditions in multiple regions of the brain, and that their connection was found in mice to be key to maintaining normal movement, memory function and anxiety regulation.

When that connection doesn’t happen as it should, they found, behavior can be negatively affected – in mice, disruption to the proteins’ ability to interact increased hyperactivity, reduced risk avoidance and impaired memory. Though delusions and hallucinations are hallmark symptoms of schizophrenia, the condition also encompasses additional symptoms, including movement and memory problems. 

“These two proteins are seemingly unrelated, and our study has provided a link between them that wasn’t recognized before,” said lead author Chen Gu, associate professor of biological chemistry and pharmacology in The Ohio State University College of Medicine.  

Directed evolution of catalysts for the energy transition

Alfred Ludwig, professor for Materials Discovery and Interfaces, is involved in the Synergy Grant from Ruhr University Bochum.
Photo Credit: © RUB, Marquard

Catalysts should be efficient and durable. To find them, four teams are systematically working together on new concepts. They are being funded by the European Research Council (ERC) with 10 million euros.

Hydrogen is considered the energy carrier of the future. To produce it, reactions have to be catalyzed, some of which take place under extreme conditions. Previous electrocatalysts usually cannot withstand this for long – new materials are needed that are both powerful and durable, and ideally do not contain expensive and scarce elements. A Danish-German-Swiss research consortium is systematically taking a new approach in the project "Directed Evolution of Metastable Electrocatalyst Interfaces for Energy Conversion", or DEMI for short. DEMI will be funded for the next six years with around 10 million euros as a Synergy Grant from the European Research Council ERC, the highest award for researchers in the EU. 

Keeping T cells in check and on target

L-R: Professor Stephen Turner & Dr Brendan Russ
Photo Credit: Courtesy of Monash University

Our immune system’s T cells kill tumors and virus-infected cells to prevent disease from spreading to healthy tissues. However, in order to recognize their target and perform their protective function, T cells must undergo a process of maturation which includes being exposed to, then remembering, the unwanted pathogen.

Monash Biomedicine Discovery Institute (BDI) researchers have generated a detailed genetic blueprint that outlines the wiring configuration needed to enhance T cell function, published in Cell Reports.

First author Dr Brendan Russ said that there is great interest in understanding how the maturation of one particular type of T cell, CD8+, is regulated, not only because the body uses CD8+ T cells to fight viral infection and cancer, but also because inappropriate maturation of T cells can result in killing of healthy tissues.

“These maturation processes underlie the ability of T cells to respond to viruses and tumors. What we want is a sweet spot for these T cells such that they become activated only when the body is actually under threat. Indeed, many cutting-edge cancer therapeutics aim to manipulate T cell maturation. So, our findings add to this body of research, and suggest a means of modulating T cell maturation to improve such therapies,” Dr Russ said.