Saturday, November 20, 2021

New link between diet, intestinal stem cells and disease discovered

How unhealthy diet makes you sick
Obesity, diabetes and gastrointestinal cancer are frequently linked to an unhealthy diet. However, the molecular mechanisms responsible for this are hitherto not fully understood. Researchers at the Technical University of Munich and Helmholtz Munich have gained some new insights that help to better understand this connection. These findings provide an important basis for the development of new, non-invasive therapies.

The intestine is essential for maintaining our energy balance and is a master at reacting quickly to changes in nutrition and nutrient balance. It manages to do this with the help of intestinal cells that among other things are specialized in the absorption of food components or the secretion of hormones.

In adult humans, the intestinal cells regenerate every five to seven days. The ability to constantly renew and develop all types of intestinal cells from intestinal stem cells is crucial for the natural adaptability of the digestive system. However, a long-term diet high in sugar and fat disrupts this adaptation and can contribute to the development of obesity, type 2 diabetes and gastrointestinal cancer.

The molecular mechanisms behind this maladaptation are part of the research field of the group of Heiko Lickert, professor for diabetes research and ß-cell biology at the Technical University of Munich and head of the Institute for Diabetes and Regeneration Research at Helmholtz Munich.

The scientists assume that intestinal stem cells play a special role in the maladaptation. Using a mouse model, the researchers investigated the effects of a high-sugar and high-fat diet and compared it with a control group.

“The first thing we noticed was that the small intestine increases greatly in size on the high-calorie diet,” says study leader Anika Böttcher. “Together with Fabian Theis’ team of computational biologists, we then profiled 27,000 intestinal cells from control diet and high fat/high sugar diet fed mice. Using new machine learning techniques, we thus found that intestinal stem cells divide and differentiate significantly faster in the mice on an unhealthy diet.”

Friday, November 19, 2021

New mothers could help protect other babies’ brains

The placenta from mothers of healthy newborns could one day be used to reduce brain injury in growth-restricted babies, according to University of Queensland research.

Dr Julie Wixey from UQ’s Centre for Clinical Research said the study found stem cells sourced from a healthy placenta may reduce damaging inflammation in these babies after only three days.

“There is currently no treatment to protect the brains of a growth-restricted baby,” Dr Wixey said.

“Up to 50 per cent of them have long term issues ranging from mild learning and behavioral disorders all the way through to cerebral palsy.

“We know there’s inflammation in the brain and it doesn’t cease once these babies are born.

“Our study has shown we could reduce inflammation and ongoing brain injury by treating these newborns on the day they’re born using a combination of two types of stem cells – endothelial colony forming cells and mesenchymal stromal cells – isolated from a healthy human placenta.”

About 32 million growth-restricted babies are born around the world each year, with around 10 per cent of newborns in Australia affected.

These babies fail to grow normally in the womb, often because they haven’t received enough nutrients and oxygen from the placenta.

Antarctic ice-sheet destabilized within a decade

Iceberg in Antarctica © Uni Bonn/ Michael Weber

After the natural warming that followed the last Ice Age, there were repeated periods when masses of icebergs broke off from Antarctica into the Southern Ocean. A new data-model study led by the University of Bonn (Germany) now shows that it took only a decade to initiate this tipping point in the climate system, and that ice mass loss then continued for many centuries. Accompanying modeling studies suggest that today's accelerating Antarctic ice mass loss also represents such a tipping point, which could lead to irreversible and long-lasting ice retreat and global sea level rise. The study has now been published in the journal Nature Communications.

Dr. Michael Weber from the Institute of Geosciences
 at the University of Bonn
© Uni Bonn/ Michael Weber
To understand what the consequences of current and future human-induced climate warming may be, it helps to take a look at the past: how did sea-level changes look like during times of natural climate warming? In a recent study, an international research team led by Dr. Michael Weber from the Institute of Geosciences at the University of Bonn investigated this question. In doing so, they focused on the Antarctic Ice Sheet as the largest remaining ice sheet on Earth.

There, they searched for evidence of icebergs that broke off the Antarctic continent, floated in the surrounding ocean and melted down in the major gateway to lower latitudes called “Iceberg Alley”. In the process, the icebergs released encapsulated debris that accumulated on the ocean floor. The team took sediment cores from the deep ocean in 3.5 km water depth from the area, dated the natural climate archive and counted the ice-rafted debris.

Thursday, November 18, 2021

Breakthrough in Fight on Tick-Borne CCHF Virus is Latest Use of New Strategy Against Diseases

A 3D atomic map, or structure, of the Gc protein (red and yellow)
bound to two antibodies (green, blue and white) produced by a recovered patient.
The Gc protein is a key molecule on the surface of the
CCHF virus enabling it to infect cells.
Credit: Akaash Mishra/University of Texas at Austin
Using the same approach they recently used to create effective vaccine candidates against COVID-19 and respiratory syncytial virus (RSV), scientists are tackling another virus: the tick-borne Crimean-Congo hemorrhagic fever (CCHF). It causes death in up to 40% of cases, and the World Health Organization identified the disease as one of its top priorities for research and development. The results appear today in the journal Science.

Using what scientists refer to as structural virology, a research consortium called Prometheus reconstructed the first 3D atomic-scale maps, or structures, of an infection-causing part of the virus that allows it to infect host cells. The team also determined how two neutralizing antibodies, fished from recovered patients, disrupt the virus’s ability to infect a cell, which together with the structural information, offers insights for developing therapeutics against the virus.

The research echoes a key approach that scientists, including The University of Texas at Austin’s Jason McLellan, have used in recent years to fight COVID-19 and RSV, signaling the emerging prominence of structural virology—the use of exquisitely detailed imaging of viral components to find their weaknesses—in preventing pandemics and curbing infectious disease.

Researchers study the link between vitamin D and inflammation

Majid Kazemian and a team of scientists have discovered
that a form of vitamin D (not the over-the-counter pills) could help combat
the inflammation in cells of people with severe cases of COVID-19.
Image Credit: Purdue University /Rebecca McElhoe.
Scientists recently gained insights into how vitamin D functions to reduce inflammation caused by immune cells that might be relevant to the responses during severe COVID-19. In a study jointly published by Purdue University and the National Institutes of Health, scientists do just that.

Majid Kazemian, assistant professor in the departments of Computer Science and Biochemistry at Purdue University, was co-lead author of the highly collaborative study, along with Dr. Behdad Afzali, chief of the Immunoregulation Section of the National Institutes of Health’s National Institute of Diabetes and Digestive and Kidney Diseases.

“Our work demonstrates a mechanism by which vitamin D reduces inflammation caused by T cells. These are important cells of the immune system and implicated as part of the immune response to the infection causing COVID-19. Further research, especially clinical trials, and testing in patients, are necessary before this can be adopted as a treatment option.” Kazemian said. “We do not recommend the use of normal vitamin D off the shelf at the pharmacy. No one should be taking more than the recommended doses of vitamin D in an attempt to prevent or combat COVID infections.”

Previously hidden environmental impact of bursting bubbles exposed in new study

In a new study, mechanical science and engineering professor Jie Feng, left, graduate student Zhengyu Yang and postdoctoral researcher Bingqiang Ji used high-speed photography to demonstrate the mechanism that allows bursting bubbles to transport organic material, such as contaminants and microbes, into the atmosphere. 
Photo Credit: by Fred Zwicky

Bubbles are common in nature and can form when ocean waves break and when raindrops impact surfaces. When bubbles burst, they send tiny jets of water and other materials into the air. A new study from the University of Illinois Urbana-Champaign examines how the interplay between bubble surfaces and water that contains organic materials contributes to the transport of aerosolized organic materials – some of which are linked to the spread of disease or contamination – into the atmosphere.

The study, led by mechanical science and engineering professor Jie Feng with postdoctoral researcher Bingqiang Ji and graduate student Zhengyu Yang, demonstrates a distinct transport mechanism occurring at the interface of bursting bubbles and the air. The study results are published in the journal Nature Communications.

“We are all familiar with how we can smell beer when it is placed in front of us,” Feng said. “The bursting bubbles in the foam send droplets of aerosolized liquid into the air. We then inhale those tiny droplets, activating our smell senses – this is the phenomenon we are examining in this study.”

Researchers develop wearable pollution-measuring technology

Shown here under the microscope is some of Mason’s past work,
tiny electronics and channels for fluids will be at the heart of the team’s sensing devices.
Image credit: Matt Davenport
Researchers at the University of Michigan, Michigan State University and Oakland University are teaming up to develop wearable technology able to identify particulate matter pollution such as soot and toxic metals generated by cars, trucks and industrial sources with a $2.78 million grant from the National Institutes of Health. The new grant work will build on the team’s previous work, including that of Andrew Mason, a professor at MSU’s College of Engineering, who will focus on developing the microscale sampling device. 

A walk in the park could soon include getting real-time measurements of pollutants in the air and updated walking routes to avoid the most toxic ones, all while wearing a gadget the size of a smart watch.

With the support of a $2.78 million grant from the National Institutes of Health, researchers at the University of Michigan, Michigan State University and Oakland University are teaming up to develop wearable technology able to identify particulate matter pollution such as soot and toxic metals generated by cars, trucks and industrial sources.

New holographic camera sees the unseen with high precision

A setup of one of the prototypes in the laboratory.
Credit: Florian Willomitzer/Northwestern University

Northwestern University researchers have invented a new high-resolution camera that can see the unseen — including around corners and through scattering media, such as skin, fog or potentially even the human skull.

  • Technology combines two light waves from lasers to create a synthetic wave field
  • The synthetic wave field reflected by a hidden object is captured as a hologram
  • An algorithm reconstructs the hologram to reveal an image of the obscured object
  • The camera could be used to help drivers see around corners to avoid accidents, as a noninvasive medical imaging device, for industrial inspection and more

Called synthetic wavelength holography, the new method works by indirectly scattering coherent light onto hidden objects, which then scatters again and travels back to a camera. From there, an algorithm reconstructs the scattered light signal to reveal the hidden objects. Due to its high temporal resolution, the method also has potential to image fast-moving objects, such as the beating heart through the chest or speeding cars around a street corner.

Resilience of vertebrate animals in rapid decline due to manmade threats

Global change is eroding life on earth at an unprecedented rate and scale. Species extinctions have accelerated over the last decades, with the concomitant loss of the functions and services they provide to human societies.

A general assumption is that this current loss of global biodiversity is paralleled by a decrease in the resilience of ecological systems. As such, preserving resilience of ecosystems has become a major conservation objective.

Now researchers at the University of Bristol have examined how species are responding to the rising environmental pressures, demonstrating in findings published today in Ecology Letters, that the planetary scale of human impacts to wildlife is also accelerating resilience loss of vertebrates worldwide.

Dr Pol Capdevila of the School of Biological Science said: “Global assessments of how the resilience of vertebrate species has changed over the last decades were absent before our study, rendering the assumption of global resilience loss untested.

“In this study, we evaluated how the resilience of vertebrate populations, including species of mammals, birds, amphibians, reptiles and fish worldwide, is changing over time. We also tested which could be the main factors accelerating the potential decline of resilience worldwide.

Revolution in imaging with neutrons

Instrument scientist Adrian Losko at the neutron radiography instrument NECTAR.
Image Credit: Bernhard Ludewig / FRM II / TUM

An international research team at the Research Neutron Source Heinz Maier-Leibnitz (FRM II) of the Technical University of Munich (TUM) have developed a new imaging technology. In the future this technology could not only improve the resolution of neutron measurements by many times but could also reduce radiation exposure during x-ray imaging.

Modern cameras still rely on the same principle they used 200 years ago: Instead of a piece of film, today an image sensor is exposed for a certain period of time in order to record an image. However, the process also records the noise of the sensor. This constitutes a considerable source of interference especially with longer exposure times.

Together with colleagues from Switzerland, France, the Netherlands and the USA, Dr. Adrian Losko and his TUM colleagues at the Heinz Maier-Leibnitz Zentrum (MLZ) have now developed a new imaging method which measures individual photons on a time-resolved and spatially-resolved basis. This makes it possible to separate photons from noise, greatly reducing the interference.

"Our new detector lets us capture every individual photon and thus overcome many of the physical limitations of traditional cameras," says Dr. Adrian Losko, instrument scientist at the NECTAR neutron radiography facility of the Heinz Maier-Leibnitz Zentrum at the Technical University of Munich.

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