Puzzling discovery in Namibia

Geologist Cees Passchier has been working in Namibia for 25 years, among other places. His research focuses on the geological reconstruction of Precambrian terranes. “We look at the structure of the rocks to find out how continents came together to form the supercontinent Gondwana 500 to 600 million years ago,” explained Passchier. At that time, carbonate deposits formed in the ancient oceans and turned into marble due to pressure and heat. “We noticed strange structures in this marble that were not the result of geological events.” Instead of smooth erosion surfaces, tubes could be seen that were about half a millimeter wide and up to three centimeters long, lined up parallel to one another and forming bands up to ten meters long. Some calcrete crusts had formed on the edges.

The first observations of this kind in the Namibian desert were made 15 years ago. In the meantime, Professor Cees Passchier, together with colleagues from the Institute of Geosciences at Mainz University, and Dr. Trudy Wassenaar, head of the consulting company Molecular Microbiology and Genomics Consultants, have continued to investigate the phenomenon. “We think that it must have been a microorganism that formed these tubes.” The tubes were not empty but filled with a fine powder of clean calcium carbonate. It is assumed that microorganisms may have bored the tunnels to use nutrients present in the calcium carbonate, the main component of marble. The fine powder remained behind. Passchier also found very similar structures during field work in Oman and in Saudi Arabia — in Oman in limestone, while in the Saudi Arabian desert they were in marble.

“In any case, these are old structures, perhaps one or two million years old,” said Passchier. “We assume that they were formed in a slightly more humid climate, not in the dry desert climate that prevails today.” However, the organism that caused these structures remains a mystery.

Endolithic microorganisms use rock as a basis for life

Microorganisms such as bacteria, fungi, or lichen are found even in inhospitable or remote corners of the Earth. So-called endolithic microorganisms are not uncommon in desert areas as they can obtain their energy and nutrients from the rocks they live in. “What is so exciting about our discovery is that we do not know which endolithic microorganism this is. Is it a known form of life or a completely unknown organism?” According to Cees Passchier, it must be an organism that can survive without light because the tubes have formed deep inside the rock. The researchers found biological material, but no DNA or proteins that could provide further insights.

Passchier hopes that specialists on endolithic organisms will look into this phenomenon in the future. “This form of life, of which we do not know whether it still exists, could be important for the global carbon cycle. It is therefore essential that the scientific community becomes aware of it.” The release of carbon through the biological activity of microorganisms could also play a major role in the Earth’s CO₂ balance.

Dietary fibres in fruit, vegetables, beans and whole grains are some of the most important food components for human health. They help digestion, weight management, blood sugar control, heart health, cancer prevention and more.

But RMIT University food scientist Professor Raj Eri said consumer advice on how best to use them for these various benefits is sorely lacking.

“Quite like how different medicines target different conditions, so too do different types of fibres,” he said.

“For example, apples and bananas are both rich in dietary fibre but the fibre in each works very differently.

“Our research is helping to understand which type of fibres we should eat to help address certain ailments.”

A new model for more tailored diets

In a new study published in Food Research International, the RMIT University team propose a more nuanced fibre classification based on five key features: backbone structure, water-holding-capacity, structural charge, fibre matrix and fermentation rate.

Study lead author and RMIT PhD candidate Christo Opperman said by starting with the key active features of fibre, this ‘bottom-up approach’more accurately described each fibre’s health impacts.

“For example, suppose you want to promote colonic health. In that case, you identify a fibre’s properties as defined by the bottom-up approach, which align with your desired outcome — in this case fermentation rate,” Opperman said.

“Applying this framework can assure consumers, dieticians, clinicians and food technologists that they are receiving their desired health effect, which previously was a vague guessing game.”

Opperman said the RMIT team have now taken 20 different types of fibres and studied how they interact specifically with microbiome in the gut.

“Until now, these types of specific interactions have been understudied, but with this framework as a beginning, we are on the verge of a much more helpful and detailed understanding,” he said.

A global fibre gap

Eri said there was already strong interest among dieticians, clinicians and food technologists — and of course consumers — on how to better integrate fibre into diets.

“In the countries surveyed, including Europe and the USA, every single population had a deficiency of fibre,” Eri said.

“Considering fibre is one of the most important nutrients, this is extremely worrying.”

While recommended dietary fibre intake is 28-42 grams per day, Americans on average get only 12-14 grams per day and Europeans 18-24 grams per day.

Beyond soluble and insoluble

The current classification of dietary fibres has them grouped into soluble and insoluble fibres, which is based on whether they dissolve in water.

Insoluble fibres are seldom fermented in the large intestine and help keep us regular.

Soluble fibres are more readily fermented and can reduce cholesterol, glucose absorption and food craving.

But it’s not always so straightforward. For example, often insoluble fibres can also rapidly ferment and reduce glucose absorption.

“Despite our evolving understanding of how central different types of fibre are to nurturing a healthy gut biome, our dietary fibre classifications remain simplistic between broad categories of soluble and insoluble types,” Eri said.

“This binary classification of soluble and insoluble insufficiently captures the diverse structures and complex mechanisms through which dietary fibres influence human physiology.”

“Our framework is an essential step in addressing this gap,” he said.

The researchers are now planning to investigate how a specific type of fibre (based on our new classification) modulates the microbiota and how we can utilise such knowledge for specific health applications.

Although Parkinson’s disease is a well-recognized illness, the term can refer to a variety of conditions, ranging from idiopathic Parkinson’s, the most common type, to other movement disorders like multiple system atrophy Parkinsonian variant and progressive supranuclear palsy. Each shares motor and nonmotor features, like changes in gait — but possess a distinct pathology and prognosis.

Roughly one in four patients, or even one in two patients, is misdiagnosed.

Now, researchers at the University of Florida and the UF Health Norman Fixel Institute for Neurological Diseases have developed a new kind of software that will help clinicians differentially diagnose Parkinson’s disease and related conditions, reducing diagnostic time and increasing precision beyond 96%. The study was published recently in JAMA Neurology and was funded by the National Institutes of Health.

“In many cases, MRI manufacturers don’t communicate with each other due to marketplace competition,” said David Vaillancourt, Ph.D., chair and a professor in the UF Department of Applied Physiology and Kinesiology. “They all have their own software and their own sequences. Here, we’ve developed novel software that works across all of them.”

Although there is no substitute for the human element of diagnosis, even the most experienced physicians who specialize in movement disorder diagnoses can benefit from a tool to increase diagnostic efficacy between different disorders, Vaillancourt said.

The software, Automated Imaging Differentiation for Parkinsonism, or AIDP, is an automated MRI processing and machine learning software that features a noninvasive biomarker technique. Using diffusion-weighted MRI, which measures how water molecules diffuse in the brain, the team can identify where neurodegeneration is occurring. Then, the machine learning algorithm, rigorously tested against in-person clinic diagnoses, analyzes the brain scan and provides the clinician with the results, indicating one of the different types of Parkinson’s.

The study was conducted across 21 sites, 19 of them in the United States and two in Canada.

“This is an instance where the innovation between technology and artificial intelligence has been proven to enhance diagnostic precision, allowing us the opportunity to further improve treatment for patients with Parkinson’s disease,” said Michael Okun, M.D., medical adviser to the Parkinson’s Foundation and director of the Norman Fixel Institute for Neurological Diseases at UF Health. “We look forward to seeing how this innovation can further impact the Parkinson’s community and advance our shared goal of better outcomes for all.”

The team’s next step is obtaining approval from the U.S. Food and Drug Administration.

“This effort truly highlights the importance of interdisciplinary collaboration,” said Angelos Barmpoutis, Ph.D., a professor at the Digital Worlds Institute at UF. “Thanks to the combined medical expertise, scientific expertise and technological expertise, we were able to accomplish a goal that will change the lives of countless individuals.”

Vaillancourt and Barmpoutis are partial owners of a company called Neuropacs whose goal is to bring this software forward, improving both patient care and clinical trials where it might be used.