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Comment by Dr. Krishna Kumari Challa on November 14, 2023 at 1:30pm

Mind-Altering Cat Parasite May Trigger Frailty in Older People

An infamous parasite primarily carried by cats, Toxoplasma gondii, could be responsible for increased frailty in older adults, a new study reveals.

The discovery, made by an international team of researchers, adds to what we already know about T. gondii: that it can cause flu-like symptoms in many, and more serious issues such as seizures in people with weaker immune systems. "We often think of T. gondii infection as relatively asymptomatic, but this study highlights that for some people it may have significant health consequences later on.

The research team suspected that the parasite may be one of the causes of 'inflammaging', or persistent age-related inflammation that contributes to frailty. Blood tests from 601 Spanish and Portuguese adults aged over 65 were analyzed for measures of frailty, including unintentional weight loss, tiredness, and loss of mental sharpness. While there wasn't an association found between T. gondii infections and frailty, among those who had been infected by T. gondii, people who produced a higher number of antibodies to fight it were more likely to show signs of being frail. To put it another way, there are signs of a link between a more severe immune reaction to this parasite, and a greater likelihood of being more frail in old age. It's not enough to prove cause and effect, but it seems there might be something going on. On the inflammaging front, those with a stronger response to T. gondii (perhaps through a more widespread infection, or multiple infections) also had higher levels of certain biomarkers of inflammation, suggesting another potential link there.

Considering infection rates for T. gondii rise as people get older, and that it can lie dormant and undetected in a human body for several decades, the researchers say we need to be even more careful when it comes to avoiding infection. That can come through exposure to T. gondii eggs (in a cat's litter box, for example, or water that they've contaminated), or through eating undercooked meat that's been infected by the parasite. Keeping cats indoors and avoiding strays can help too.

https://academic.oup.com/biomedgerontology/advance-article/doi/10.1...

Comment by Dr. Krishna Kumari Challa on November 14, 2023 at 1:22pm

The Remains of an Ancient Planet Lie Deep Within Earth

Comment by Dr. Krishna Kumari Challa on November 14, 2023 at 1:03pm

Physicists trap electrons in a 3D crystal for the first time

 Electrons move through a conducting material like commuters at the height of Manhattan rush hour. The charged particles may jostle and bump against each other, but for the most part they’re unconcerned with other electrons as they hurtle forward, each with their own energy.

But when a material’s electrons are trapped together, they can settle into the exact same energy state and start to behave as one. This collective, zombie-like state is what’s known in physics as an electronic “flat band,” and scientists predict that when electrons are in this state they can start to feel the quantum effects of other electrons and act in coordinated, quantum ways. Then, exotic behavior such as superconductivity and unique forms of magnetism may emerge.

Now, physicists have successfully trapped electrons in a pure crystal. It is the first time that scientists have achieved an electronic flat band in a three-dimensional material. With some chemical manipulation, the researchers also showed they could transform the crystal into a superconductor — a material that conducts electricity with zero resistance.

The electrons’ trapped state is possible thanks to the crystal’s atomic geometry. The crystal, which the physicists synthesized, has an arrangement of atoms that resembles the woven patterns in “kagome,” the Japanese art of basket-weaving. In this specific geometry, the researchers found that rather than jumping between atoms, electrons were “caged,” and settled into the same band of energy.

The researchers say that this flat-band state can be realized with virtually any combination of atoms — as long as they are arranged in this kagome-inspired 3D geometry. The results, published in Nature, provide a new way for scientists to explore rare electronic states in three-dimensional materials. These materials might someday be optimized to enable ultraefficient power lines, supercomputing quantum bits, and faster, smarter electronic devices.

https://news.mit.edu/2023/physicists-trap-electrons-3d-crystal-firs...

Comment by Dr. Krishna Kumari Challa on November 14, 2023 at 11:42am

Forests with multiple tree species are 70% more effective as carbon sinks than monoculture forests, study finds

To slow the effects of climate change, conserve biodiversity, and meet the sustainable development goals, replanting trees is vital. Restored forests store carbon within the forest's soil, shrubs, and trees. Mixed forests are especially effective at carbon storage, as different species with complementary traits can increase overall carbon storage.

Compared to single-species forests, mixed forests are also more resilient to pests, diseases, and climatic disturbances, which increases their long-term carbon storage potential. The delivery of other ecosystem services is also greater in mixed species forests, and they support higher levels of biodiversity.

Although the benefits of diverse forest systems are well known, many countries' restoration commitments are focused on establishing monoculture plantations. Given this practice, an international team of scientists has compared carbon stocks in mixed planted forests to carbon stocks in commercial and best-performing monocultures, as well as the average of monocultures.

Diverse planted forests store more carbon than monocultures—upwards of 70%. Researchers also found the greatest increase in carbon storage relative to monocultures in four-species mixtures.

The mixed planted forests assessed in the study ranged in species richness from two to six species. In the data set the scientists worked with, four-species mixtures were the most effective carbon sinks. One such mix was made up from different broadleaf trees. Mixes with two species also had greater above-ground carbon stocks than monocultures and stored up to 35% more carbon. 

Accordingly, the researchers were able to show that diversification of forests enhances carbon storage. Altogether, above-ground carbon stocks in mixed forests were 70% higher than in the average monoculture. The researchers also found that mixed forests had 77% higher carbon stocks than commercial monocultures, made up of species bred to be particularly high yielding.

Young mixed planted forests store more carbon than monocultures—a meta-analysis, Frontiers in Forests and Global Change (2023). DOI: 10.3389/ffgc.2023.1226514

Comment by Dr. Krishna Kumari Challa on November 13, 2023 at 11:49am

Each of Your Nostrils Smells The World Uniquely, Study Reveals

It's not immediately noticeable to us, but our two nostrils are actually working independently in some ways and appear to have their own separate sense of smell.

That's the conclusion of a new study from researchers in the US that could teach us much more about the brain and how senses are processed. The findings build on earlier studies in animals and humans, indicating that our brains might be capable of processing each nostril's input individually as well as synthesizing them into one complete whole.

To look more closely at smelling in stereo, the researchers from the University of Pennsylvania, the Barrow Neurological Institute, and Ohio State University enlisted the help of 10 epilepsy patients who had already had electrodes implanted in their brains.

One of three different scents, as well as a control consisting of pure air, was puffed into either nostril or both together in each trial. After several seconds, the subject was asked to identify the smell, then state which nostril they used to detect it - left, right, or both. Meanwhile, the researchers collected data on the brain's response via the electrodes.

The team made a number of interesting observations. For example, when the same smell was presented to each nostril in turn, the resulting brain activity was similar, but not identical, suggesting some independence.

What's more, smelling through two nostrils together created two distinct bursts of activity. Though the time delay between them was very short, it was there, and the researchers suggest that this again points to the nostrils not always being in unison. Two nostrils were better than one when it came to identifying odors and identifying them more quickly, which hints that there's definitely some benefit to having two nostrils rather than one – as with eyes and ears. The analysis concentrated on the piriform cortex (PC) brain region, where the sense of smell is handled and interpreted. As we already know, our different senses are closely interconnected too, which means the findings may have implications beyond smell.

https://www.cell.com/current-biology/fulltext/S0960-9822(23)01379-9

Comment by Dr. Krishna Kumari Challa on November 13, 2023 at 11:44am

Liver cells age differently depending on where they are in the organ

 People age at different rates. But what about inside of a living body? Do all cells age in the same way? And does the location of a cell in the organ make a difference to the ageing process? Researchers  have now shown in the liver of mice that liver cells age differently depending on where they are located in the organ.

The liver is largely made up of a single type of cell, the hepatocyte. Depending on where they are in the liver, they have different roles. Near the portal vein, where fresh, oxygen-rich blood enters the liver, hepatocytes use the oxygen to process fats in their mitochondria and produce energy. In contrast, carbohydrates are broken down in the less oxygen-rich regions of the liver. "In the liver, the position of the hepatocyte in the organ plays a crucial role. That's why the liver was the perfect model for us to investigate whether location also makes a difference in ageing.

The location of the liver cells has a strong influence on the ageing process. In the region of the liver where the liver cells use oxygen for energy production in their mitochondria, this process deteriorates significantly with age. In the central, oxygen-deprived area of the liver, however, the researchers found no change in the mitochondria, but a change in the cells' fat metabolism.

It is important where a cell ages. They age differently depending on where they are located and what their function is, according to these researchers. 

https://www.mpg.de/21085057/1109-balt-location-location-location-15...

Comment by Dr. Krishna Kumari Challa on November 13, 2023 at 11:39am

Semantic hearing: Future of intelligent hearables

Comment by Dr. Krishna Kumari Challa on November 12, 2023 at 9:11am

 They began synthesizing and testing derivatives with slight changes to the region that binds to ergosterol and cholesterol, while also boosting the kinetics of the ergosterol-removing process to maintain efficacy.

 The researchers tested the most promising derivatives – first with in vitro assays, quickly assessing the efficacy in killing fungi; then moving to cell cultures and eventually live mice, assessing toxicity.

The researchers tested this molecule against over 500 different clinically relevant pathogen species in four different locations. And this molecule completely surprised us by either mimicking or surpassing the efficacy of current clinically available antifungal drugs.

The researchers tested AM-2-19 in human blood and kidney cells to screen for toxicity. They also tested AM-2-19 in mouse models of three common, stubborn fungal infections and saw high efficacy.

Maji, A. et al. Tuning sterol extraction kinetics yields a renal-sparing polyene antifungal. Nature https://doi.org/10.1038/s41586-023-06710-4 (2023).

Part 2

Comment by Dr. Krishna Kumari Challa on November 12, 2023 at 9:07am

New antifungal molecule kills fungi without toxicity in human cells, mice

A new antifungal molecule, devised by tweaking the structure of prominent antifungal drug Amphotericin B, has the potential to harness the drug’s power against fungal infections while doing away with its toxicity, researchers  reported in the journal Nature.

Amphotericin B, a naturally occurring small molecule produced by bacteria, is a drug used as a last resort to treat fungal infections. While AmB excels at killing fungi, it is reserved as a last line of defense because it also is toxic to the human patient – particularly the kidneys.

This work is a demonstration that, by going deep into the fundamental science, you can take a billion-year head start from nature and turn it into something that hopefully is going to have a big impact on human health.

These researchers spent years exploring AmB in hopes of making a derivative that can kill fungi without harm to humans. In previous studies, they developed and leveraged a building block-based approach to molecular synthesis and teamed up with a group specializing in molecular imaging tools called solid-state nuclear magnetic resonance. They  uncovered the mechanism of the drug: AmB kills fungi by acting like a sponge to extract ergosterol from fungal cells.

The researchers also found that that AmB similarly kills human kidney cells by extracting cholesterol, the most common sterol in people. The researchers also resolved the atomic-level structure of AmB sponges when bound to both ergosterol and to cholesterol.

Using this structural information along with functional and computational studies, they achieved a significant breakthrough in understanding how AmB functions as a potent fungicidal drug. This provided the insights to modify AmB and tune its binding properties, reducing its interaction with cholesterol and thereby reducing the toxicity.

Part 1

Comment by Dr. Krishna Kumari Challa on November 12, 2023 at 8:47am

How animals get their stripes and spots

Nature has no shortage of patterns, from spots on leopards to stripes on zebras and hexagons on boxfish. But a full explanation for how these patterns form has remained elusive.

Now engineers  have shown that the same physical process that helps remove dirt from laundry could play a role in how tropical fish get their colorful stripes and spots. Their findings were published Nov. 8 in the journal Science Advances.

Biologists have previously shown that many animals evolved to have coat patterns to camouflage themselves or attract mates. While genes encode pattern information like the color of a leopard’s spots, genetics alone do not explain where exactly the spots will develop, for example.

In 1952, before biologists discovered the double helix structure of DNA, Alan Turing, the mathematician who invented modern computing, proposed a bold theory of how animals got their patterns.

Turing hypothesized that as tissues develop, they produce chemical agents. These agents diffuse through tissue in a process similar to adding milk to coffee. Some of the agents react with each other, forming spots. Others inhibit the spread and reaction of the agents, forming space between spots. Turing’s theory suggested that instead of complex genetic processes, this simple reaction-diffusion model could be enough to explain the basics of biological pattern formation.

Surely Turing’s mechanism can produce patterns, but diffusion doesn’t yield sharp patterns.

Where particles  form sharply defined stripes,  the process known as diffusiophoresis plays a role in nature’s pattern formation.

Diffusiophoresis happens when a molecule moves through liquid in response to changes, such as differences in concentrations, and accelerates the movement of other types of molecules in the same environment. While it may seem like an obscure concept to non-scientists, it’s actually how laundry gets clean.

One recent study showed that rinsing soap-soaked clothes in clean water removes the dirt faster than rinsing soap-soaked clothes in soapy water. This is because when soap diffuses out of the fabric into water with lower soap concentration, the movement of soap molecules draws out the dirt. When the clothes are put in soapy water, the lack of a difference in soap concentration causes the dirt to stay in place.

The movement of molecules during diffusiophoresis, as researchers observed in their simulations, always follows a clear trajectory and gives rise to patterns with sharp outlines. To see if it may play a role in giving animals their vivid patterns, researchers ran a simulation of the purple and black hexagonal pattern seen on the ornate boxfish skin using only the Turing equations. The computer produced a picture of blurry purple dots with a faint black outline. Then the team modified the equations to incorporate diffusiophoresis. The result turned out to be much more similar to the bright and sharp bi-color hexagonal pattern seen on the fish.

The research team’s theory suggests that when chemical agents diffuse through tissue as Turing described, they also drag pigment-producing cells with them through diffusiophoresis—just like soap pulls dirt out of laundry. These pigment cells form spots and stripes with a much sharper outline.

 Benjamin Alessio et al, Diffusiophoresis-Enhanced Turing Patterns, Science Advances (2023). DOI: 10.1126/sciadv.adj2457. www.science.org/doi/10.1126/sciadv.adj2457

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