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Comment by Dr. Krishna Kumari Challa 2 hours ago

By exerting 'crowd control' over mouse cells, scientists make progress towards engineering tissues
Genes aren't the sole driver instructing cells to build multicellular structures, tissues, and organs. In a paper published in Nature Communications, scientists characterize the influence of another important developmental driver: cell density, or how loosely or tightly cells are packed into a given space.

In both computational models and laboratory experiments, the team of scientists used cell density as an effective tool for controlling how mouse cells pattern themselves into complex structures.

This paper represents progress towards their big picture goal of engineering synthetic tissues. Synthetic tissues could have endless medical applications, ranging from testing potential drugs or therapies to providing grafts or transplants for patients.

The study used two types of mouse cells—connective tissue cells and stem cells—engineered to carry a synthetic cellular communication system or "genetic circuit. This circuit is based on something they developed called "synNotch," which is a protein that scientists genetically engineer into a cell to serve as a "sensor."

Located on a cell's surface, this protein-based sensor recognizes an external signal that triggers the cell to respond—usually by turning on a user-defined gene.

For this particular series of experiments, the scientists used synNotch to turn on a circuit that includes green fluorescence and a way to propagate the signal further—although it could be used to turn on any gene. The fluorescence made it easy to observe cells as they formed patterns. For example, in a field of cells, scientists could create a pattern of green fluorescent rings emanating from a central point.

While conducting these experiments, the scientists noticed that genetically identical cells did not always produce the same patterns.

So that was puzzling at the beginning. When the researchers looked at it more carefully, they started seeing that there was a gradient of cell density that seemed to correlate with differences in patterning.

Part 1

Comment by Dr. Krishna Kumari Challa 2 hours ago

High exposure to everyday chemicals linked to asthma risk in children

A new study by researchers at Kumamoto University sheds light on a potential link between exposure to certain everyday chemicals during pregnancy and the development of asthma in children. The study analyzed data from over 3,500 mother-child pairs as part of the Japan Environment and Children's Study (JECS), a large-scale nationwide research project.

researchers measured 24 types of phenols in urine samples collected from pregnant women. They then tracked the health of their children until the age of four.

The study is published in the journal Environmental Pollution.

High levels of butylparaben, a chemical commonly used in personal care products like lotions and shampoos, during early pregnanacy were associated with a 1.54-fold increase in the odds of asthma development in children (Odds Ratio: 1.54).

Exposure to 4-nonylphenol, a chemical found in some cleaning products and plastics, showed a striking gender-specific effect. Boys born to mothers exposed to this chemical had 2.09 times higher odds of developing asthma, while no such association was observed in girls.

Phenols, including parabens and alkylphenols, are widely used in consumer products for their preservative and antimicrobial properties. While their use is considered safe in small amounts, their potential as endocrine disruptors raises concerns about long-term health effects, such as the recent increase in allergenic diseases such as asthma, particularly during sensitive periods like pregnancy.

The findings highlight the importance of understanding how everyday chemical exposures might contribute to respiratory and allergic conditions in children.

Shohei Kuraoka et al, Association of phenol exposure during pregnancy and asthma development in children: The Japan Environment and Children's study, Environmental Pollution (2024). DOI: 10.1016/j.envpol.2024.124801

Comment by Dr. Krishna Kumari Challa 2 hours ago

Researchers uncover how blood pressure drugs harm kidneys

Commonly prescribed drugs used to treat high blood pressure have been shown to, over time, wreck the kidneys' ability to filter and purify blood. How does this happen?

Researchers found that the drugs essentially rewire the kidneys to do something other than the important work of filtering blood. The kidneys start producing more of a hormone called renin; nerve endings grow excessively; cells lining the kidneys' tiny blood vessels get too large; scars form and spread; and inflammation sets in, which "can take a terrible toll on the kidney.

The result, outlined in the researchers' paper in the journal Circulation Research, is a "silent but serious" vascular disease where the kidneys become zombie-like, changing into something unwanted and unwelcome while abandoning their critical duties.

Now that they know the cause, researchers say the next step is to figure out how to use the effective blood pressure drugs known as renin-angiotensin system inhibitors—often called RAS inhibitors—while stopping the kidney-damaging effects.

RAS inhibitors, which include the generics enalapril, lisinopril, ramipril and others, are commonly prescribed when a patient is first diagnosed with high BP.

The drugs work by relaxing blood vessels and allowing blood to flow more freely. The medicines are widely used and generally considered safe, researchers say, but are not without risk. Doctors have long warned patients that certain blood pressure medications could cause kidney damage, often first noticed as a reduction in the frequency of urination, swelling in the legs or feet, or seizures.

Now that scientists understand what is causing the kidney changes, they can look for ways to stop it.

These findings may open new avenues for the prevention of adverse effects when treating hypertension.

Manako Yamaguchi et al, Transformation of the Kidney into a Pathological Neuro-Immune-Endocrine Organ, Circulation Research (2024). DOI: 10.1161/CIRCRESAHA.124.325305

Comment by Dr. Krishna Kumari Challa yesterday

Scientists convert plastics into soaps and detergents

Researchers found  a way to convert certain plastics into soaps, detergents, lubricants, and other products.

  The process has two steps. It first involved using thermolysis, or breaking down a substance—in this case, plastic—by using heat. Plastic placed in a reactor built by the research team and heated to between 650 and 750 degrees Fahrenheit broke down into chemical compounds, leaving a mixture of oil, gas, and residual solids.

The key to this first step was breaking down the polypropylene and polyethylene molecules that make up plastic within a certain carbon range, and Liu and his team were able to accomplish this.

The residual solids left behind were minimal, and the gas could be captured and used as fuel. The oil, though, was the product of the most interest here.

They were also was able to functionalize, or change the chemistry, of the oil into molecules to be converted into soaps, detergents, lubricants, and other products.

These materials are stable. You could use them  to wash your hands and dishes. The researchers have used them to wash their lab glassware in the laboratory.

The process, which took less than a day, led to almost zero air pollution output, thus offering clues to a desperately needed solution to a global problem.

Nuwayo Eric Munyaneza et al, Chain-length-controllable upcycling of polyolefins to sulfate detergents, Nature Sustainability (2024). DOI: 10.1038/s41893-024-01464-x

Comment by Dr. Krishna Kumari Challa yesterday

Scientists transform blood into regenerative materials, paving the way for personalized, 3D-printed implants

Scientists have created a new 'biocooperative' material based on blood, which has been shown to successfully repair bones, paving the way for personalized regenerative blood products that could be used as effective therapies to treat injury and disease.

Researchers have used peptide molecules that can guide key processes taking place during the natural healing of tissues to create living materials that enhance tissue regeneration. The research is published in Advanced Materials.

Most of our body tissues have evolved to regenerate ruptures or fractures with remarkable efficacy, as long as these are small in size. This healing process is highly complex. The initial stages rely on liquid blood forming the solid regenerative hematoma (RH), a rich and living microenvironment comprising key cells, macromolecules, and factors that orchestrate regeneration.
The team developed a self-assembling methodology where synthetic peptides are mixed with whole blood taken from the patient to create a material that harnesses key molecules, cells, and mechanisms of the natural healing process. In this way, it was possible to engineer regenerative materials capable of not only mimicking the natural RH, but also enhancing its structural and functional properties.
These materials can be easily assembled, manipulated, and even 3D printed while maintaining normal functions of the natural RH, such as normal platelet behavior, generation of growth factors, and recruitment of relevant cells important for healing. With this method, the team has shown the capacity to successfully repair bone in animal models using the animal's own blood.

Soraya Padilla‐Lopategui et al, Biocooperative Regenerative Materials by Harnessing Blood‐Clotting and Peptide Self‐Assembly, Advanced Materials (2024). DOI: 10.1002/adma.202407156

Comment by Dr. Krishna Kumari Challa yesterday

Lemongrass consists of a more floral and earthy aroma, while the other aromas are pungent, spicy or sweet. This difference in profile may explain why lemongrass seemed less intense in the VR setting compared to the microgravity posture.
In an Earth-like setting, eating was often social, but eating in space on long missions can feel quite different.
Pilot studies [published open-access in the journal Science Talks] show that spending 10 minutes in VR can induce feelings of confinement, highlighting VR's effectiveness over other methods such as immersive screens.

"Results indicate that a remote, confined environment such as the ISS and a significant variation in personal sensitivities influence aroma perception, making certain foods smell strange.
Space studies often emphasized microgravity as the main contributing factor to food's different taste, but the team's findings underscored the impact of confined and isolated environments.
This research opens possibilities for personalized meal plans for astronauts and individuals living alone on Earth, showcasing VR's potential to explore variations in eating when stressed.
In the VR setting, participants reporting positive emotions perceived stronger aromas.This link between stress and vinegar may help explain why astronauts like to eat certain foods in microgravity that they don't normally enjoy on Earth.

Food odour perception and affective response in virtual spacecraft and microgravity body posture (1-G) – potential ground-based simulations, Food Research International (2024).

Julia Low et al, Development of a virtual reality spacecraft environment as a ground-based analog for collecting space food sensory data ('Food in Space'), Science Talks (2024). DOI: 10.1016/j.sctalk.2024.100391

Alicia Tran et al, Exploring fundamentals of immersive environment setups on food sensory perception in space contexts, Science Talks (2024). DOI: 10.1016/j.sctalk.2024.100403

Part 2

Comment by Dr. Krishna Kumari Challa yesterday

Confinement may affect how we smell and feel about food

New research  found confined and isolating environments changed the way people smelled and responded emotionally to certain food aromas.

The team in this study compared 44 people's emotional responses and perception of eight food aromas in two environmental scenarios: sitting in reclined chairs that mimic astronauts' posture in microgravity; and then in the confined setting of the International Space Station (ISS), which was simulated for participants with virtual reality goggles.
The aromas the team tested on participants were vanilla, almond, lemon, lemon myrtle, eucalyptus, peppermint, vinegar and lemongrass.

The research, published in Food Research International, builds on previous work by the team and aims to help explain why astronauts report meals taste different in space and struggle to eat their normal nutritional intake over long missions, which has been reported in the news recently.

The study has broader implications for further research to improve the diets of isolated people, including nursing home residents, by personalizing aromas to enhance the flavor of their food.
Part 1

Comment by Dr. Krishna Kumari Challa yesterday

The effort resulted in an impressive 775 grassroots submissions, which the researchers then combined with satellite observations and advanced modeling techniques to explore the conditions that had led to the magenta aurora.

The elevation data from these citizen scientists proved to be particularly useful. The researchers used elevation angles to calculate the position of the aurora over time, and found that it was often a surprisingly high altitude of roughly 1,000 km above sea level—which should thus drive a red appearance. But on top of this, the time and season of year meant the atmosphere was more "preheated" ahead of the aurora, in turn driving an upwelling of ionized molecular nitrogen—what is usually responsible for a blue hue.
"Blue plus red makes us see magenta.
And the magenta was made all the more visible and vibrant by the sheer volume of solar activity, even though, ironically, the preheating would also have worked to reduce the peak brightness of the aurora."
Better understanding of magnetic storms goes beyond explaining why humans see the pretty colors of aurorae; these storms can have profound, negative impacts on satellite operations, GPS systems, power grids and even the safety of passengers and crews aboard high-altitude flights.

 Ryuho Kataoka et al, Extended magenta aurora as revealed by citizen science, Scientific Reports (2024). DOI: 10.1038/s41598-024-75184-9

Part 3

Comment by Dr. Krishna Kumari Challa yesterday

In Japan, space weather researchers took advantage of ordinary people taking pictures of the aurora with their smartphones to organize one of the densest citizen science observation efforts anywhere, despite being a low-latitude country where the aurora was somewhat fainter than in places like Canada or northern Europe.

The different colors of an aurora come from the emission of light from different atoms and molecules in the atmosphere when they are bombarded by the particles from space. The dramatic green hue seen in many photographs of the polar lights comes from atomic oxygen (single atoms of oxygen rather than molecular oxygen, or two oxygen atoms bound together) at the lower altitudes within the atmosphere that are visible to people. (The human eye is also just very sensitive to this color). At even lower altitudes, where atomic oxygen is less common, blue is more visible, and this comes from the greater presence of nitrogen.

At the very highest altitudes in the atmosphere, however, there is a lower concentration of atoms of any kind. The fewer collisions there result in a perception by humans of the excited atomic oxygen atoms as the color red. This is why the upper parts of the aurora curtains can appear as green fading into a scarlet hue.
At low latitudes, as in Japan, normally there is no green at all, only red because only the upper part of the aurora can be seen above the horizon.

"Yet this time, weirdly, the images revealed a very clear and dominant magenta hue to the aurora 'curtains' over Japan, not red.
To solve the mystery, the researchers quickly took to social media to encourage people to observe and report their sightings of the auroras, as well as to input data into a questionnaire asking about observation locations, time, elevation angles and other details, allowing researchers to analyze the auroras' characteristics in unprecedented detail.
Part 2

Comment by Dr. Krishna Kumari Challa yesterday

Magenta aurora over Japan

Why May 2024's aurora appeared a magenta color over Japan?

Around the world, the historic geomagnetic superstorm of late spring 2024 inspired millions of non-scientists around the world—many armed with highly sensitive smartphone cameras—to take a fantastic, unprecedented number of images of the aurora it produced.

In Japan, this widespread popular uptake of what is now quite advanced imaging technology (even if it is kept in everyone's pocket) proved to be a tremendous boon for atmospheric physicists and other scientists specializing in "space weather." It allowed them to discover why the Northern Lights over Japan appeared as a mysterious magenta color this time instead of the typical red that is observed when aurorae are visible over that country.

In early May this year, one of the most extreme geomagnetic storms in the history of recording such events hit the Earth's atmosphere. This great "storm" in space, composed of ionized particles, is what produces the aurora borealis, or Northern Lights, in the northern hemisphere and the aurora australis, or Southern Lights, in the southern hemisphere.

This time, however, the storm was so strong—the ninth most severe storm in the 110-year history of Japan's Kakioka Magnetic Observatory, one of the oldest geomagnetic stations in the world—that the polar lights could be photographed at much lower latitudes than normal.
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