Comment

Comment by Dr. Krishna Kumari Challa on August 17, 2024 at 10:58am

A South Asian person with a BMI of around 22 kg/m²—well within the "normal" weight range—has an equivalent risk of type 2 diabetes as a white European person with a BMI of 30 kg/m² (the conventional threshold for obesity).

The adverse metabolic consequences of weight gain in the South Asian men appeared to be related to the size of fat cells at baseline, and the change in the amount of fat in small fat cells.

The South Asians had larger fat cells before weight gain and appeared to be unable to recruit small fat cells to grow into larger fat cells with weight gain. This suggests that, unlike white Europeans, the fat was more likely to go into other areas such as the liver, which can have adverse metabolic consequences.

 found that when young, lean white European men gained a little weight—about 5 kg—they did not experience any substantial adverse metabolic consequences; but when young, lean South Asian men gained the same amount of weight, they started to exhibit metabolic dysfunction.

"Insulin sensitivity decreased by 38% in South Asians, but only by 7% in white Europeans, indicating that South Asians were not able to buffer against the adverse effects of weight gain in the way that their white European counterparts were able to.

This appears to be related, at least in part, to differences in the size of fat cells between South Asian and white European men, and how they respond to the effects of weight gain.

The South Asian men had more large fat cells, and the very small fat cells that they had were less able to grow in size as they put on weight. Both these factors were related to the adverse metabolic changes with weight gain.

Another interesting observation was that when the European men put on weight, they put on some lean tissue as well as fat tissue, but the South Asian men essentially just put on fat tissue.

This may be important, as increasing lean tissue may help protect against some of the adverse effects of weight gain, as sugar is cleared from the blood in lean tissue, or muscle.

The study's findings reinforce the need for the prevention of weight gain in South Asian men, in order to prevent further risk of type 2 diabetes.

James McLaren et al, Weight gain leads to greater adverse metabolic responses in South Asian compared with white European men: the GlasVEGAS study, Nature Metabolism (2024). DOI: 10.1038/s42255-024-01101-z

Part 2

Comment by Dr. Krishna Kumari Challa on August 17, 2024 at 10:55am

Weight gain appears to have greater metabolic consequences in South Asian men

Gaining even a small amount of weight may lead to adverse metabolic responses in young South Asian men according to new research.

The study— published in Nature Metabolism—may shed light on why South Asians are at greater risk of developing type 2 diabetes compared with other ethnic groups, and why their risk of diabetes increases more steeply with increasing BMI.

The research—which is part of the GlasVegas (Glasgow visceral and ectopic fat with weight gain in South Asians) study—investigated 14 young normal weight men of South Asian ethnic origin and 21 men of white European ethnicity before and after an overfeeding protocol to gain approximately 5 kg in weight ( please note the small sample size).

The main finding was that this modest weight gain resulted in substantial adverse metabolic responses in the South Asian men. In contrast, the white European men appeared to exhibit a degree of "metabolic buffering capacity," such that the same weight gain led to much smaller metabolic changes. Insulin sensitivity—or how well body tissues respond to insulin—decreased by 38% in the South Asian men, but only by 7% in the white Europeans.

South Asians comprise about a quarter of the world's population and have 3–5 times the prevalence of type 2 diabetes compared to white Europeans. South Asians also develop type 2 diabetes at much lower BMIs (Body Mass Indexes) than white Europeans.

Part 1

Comment by Dr. Krishna Kumari Challa on August 17, 2024 at 10:45am

Uterus transplants are leading to healthy pregnancies

till now, that is.

Uterine transplants are relatively rare and recent—the first was performed in 2011, and to date a little more than 100 transplants have been conducted worldwide.

However, a new study finds that these procedures are often successful, leading to pregnancies and live births in 14 out of the 20 patients assessed.

"A successfully transplanted uterus is capable of functioning at least on par with a native, in situ uterus," concluded a research team who assessed the outcomes.

As the researchers explained, uterus transplants are typically needed by women with what's known as "absolute uterine infertility," a condition affecting about 1 in every 500 women where the organ is either dysfunctional or absent.

In the past, these women would have had to resort to adoption or surrogacy, but 13 years ago doctors first transplanted a donated uterus into a woman with uterine infertility.

Since then, the procedure has gained acceptance.

Just how successful are these transplants?

The Dallas team tracked outcomes for 20 women averaging 30 years of age who opted for uterus transplant at their facility between 2016 and 2019.

Organs came from 18 living donors and 2 deceased donors.

In 14 of the women who underwent uterus transplant, the operation was successful, the study found, and "all 14 recipients gave birth to at least 1 live-born infant."

Complications were common and occurred in 50% of these pregnancies, with gestational high blood pressure and preterm labor being two of the most common. However, "congenital abnormalities and developmental delays have not occurred to date in [any of] the live-born children," the researchers noted. Overall, uterus transplant was "technically feasible and was associated with a high live birth rate," the team concluded.

Giuliano Testa et al, Uterus Transplant in Women With Absolute Uterine-Factor Infertility, JAMA (2024). DOI: 10.1001/jama.2024.11679

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Comment by Dr. Krishna Kumari Challa on August 17, 2024 at 10:04am

Heatstroke happens when a person is exposed to high temperatures... and their body is not able to regulate that temperature. If you go out in the sun at 42C or exercise at those temperatures, your body is unable -- no matter how much it sweats, which is the main mechanism for regulating heat -- to lower and maintain its temperature at 37C.

When your body is no longer at 37C... your organs stop working properly, including your brain. Then hyperthermia sets in and the person can die.

How heat waves affects culture: (heat culture)

In 2003, Europe suffered a brutal heat wave and 70,000 people died in 15 days. People were not prepared, and there were no prevention plans, which meant it had a brutal impact on mortality. Now nobody doubts that heat kills.
But people adapt. Between 1983 to 2003, for every degree above the temperature classed as a heat wave, the mortality in Spain increased by 14 percent. But after 2003, it barely increased by three percent.

In a city like Madrid, you never used to see older people wearing shorts but nowadays they all wear them -- you see them going out for a walk wearing a hat and with a bottle of water.

In places where they are used to having heat waves, there are now much more air conditioning units and secondly, homes are much more adapted to cope with this heat.

People don't go out from 3:00 pm, that's why the siesta exists in Spain. And in the southern Andalusia region, the villages are painted white and the streets are wide so the wind can freely circulate.

Source: AFP and other news agencies

Part 2

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Comment by Dr. Krishna Kumari Challa on August 17, 2024 at 10:01am

During a heat wave temperatures are not the only threat!

Isn't heat what kills during a heat wave?

Experts say, more things can kill you during a heat wave!

The impact of heat on health is far more than just temperature... its effect can be felt across income levels, age groups, socio-economic conditions, health care, and different cultural approaches to heat.

If you divide a country into several regions, 40 degrees Celsius (104 Fahrenheit) is not even classed as a heat wave in some areas, whereas in others, the temperature which defines a heat wave can be just 26 degrees.

When there is a heat wave, only 3.0 percent of mortality is due to heat stroke. Heat kills by aggravating other illnesses.

In the first heat wave (of the year) much more people are likely to be susceptible (to death) than the second because it claims the frailest, leaving fewer susceptible people in the second and fewer still in the third... That's why the first heat wave always has a greater impact on mortality. This is what epidemiology experts call the 'harvest effect'.

It's clear that the impact of heat is much greater in poorer neighborhoods.

It is not the same thing to experience a heat wave in a room with three people and one window and no air conditioning or fan, than going through the same thing in a villa with a swimming pool.

It's not even a question of having air conditioning or not, but about being able to turn it on. During a heat wave, the price of electricity in some countries can  skyrocket making it unaffordable for many!

Part 1

Comment by Dr. Krishna Kumari Challa on August 17, 2024 at 9:33am

Sounds of soil heartbeat: How underground acoustics can amplify soil health

Barely audible to human ears, healthy soils produce a cacophony of sounds in many forms—a bit like an underground rave concert of bubble pops and clicks.

Special recordings made by Flinders University ecologists in Australia show that this chaotic mixture of soundscapes can be a measure of the diversity of tiny living animals in the soil, which create sounds as they move and interact with their environment.

 Acoustic complexity and diversity of  samples are associated with soil invertebrate abundance—from earthworms, beetles to ants and spiders—and it seems to be a clear reflection of soil health.

All living organisms produce sounds, and these preliminary results suggest different soil organisms make different sound profiles depending on their activity, shape, appendages and size. Understanding it makes a better prediction of soil health.

This technology holds promise in addressing the global need for more effective soil biodiversity monitoring methods to protect our planet's most diverse ecosystems.

Sounds of the underground reflect soil biodiversity dynamics across a grassy woodland restoration chronosequence, Journal of Applied Ecology (2024). DOI: 10.1111/1365-2664.14738

Comment by Dr. Krishna Kumari Challa on August 17, 2024 at 9:23am

The banana apocalypse is near, but biologists  have found a key to their survival

The bananas in your supermarket and that you eat for breakfast are facing functional extinction due to the disease Fusarium wilt of banana (FWB), caused by a fungal pathogen called Fusarium oxysporum f.sp. cubense (Foc) tropical race 4 (TR4).

However, thanks to recent research by an international team of scientists  we now know that Foc TR4 did not evolve from the strain that wiped out commercial banana crops in the 1950s, and that the virulence of this new strain seems to be caused by some accessory genes that are associated the production of nitric oxide.

The research, published in Nature Microbiology, opens the door to treatments and strategies that can slow—if not control—the as-of-yet unchecked spread of Foc TR4.

The kind of banana we eat today is not the same as the one your grandparents ate. Those old ones, the Gros Michel bananas, are functionally extinct, victims of the first Fusarium outbreak in the 1950s.

Today, the most popular type of commercially available banana is the Cavendish variety, which was bred as a disease-resistant response to the Gros Michel extinction. For about 40 years, the Cavendish banana thrived across the globe in the vast monocultured plantations that supply the majority of the world's commercial banana crop.

But by the 1990s, the good times for the Cavendish banana had begun to come to a close. There was another outbreak of banana wilt. It spread like wildfire from southeast Asia to Africa and Central America.

Scientists have spent the last 10 years studying this new outbreak of banana wilt.

As a result of their hard work, we now know that the Cavendish banana-destroying pathogen TR4 did not evolve from the race that decimated the Gros Michel bananas. TR4's genome contains some accessory genes that are linked to the production of nitric oxide, which seems to be the key factor in TR4's virulence.

While the research team working on the problem  doesn't yet know exactly how these activities contribute to disease infestation in Cavendish banana, they were able to determine that the virulence of Foc TR4 was greatly reduced when two genes that control nitric oxide production were eliminated.

Identifying these accessory genetic sequences opens up many strategic avenues to mitigate—or even control—the spread of Foc TR4.

The researchers are quick to point out that the ultimate problem facing one of our favorite fruits is the practice of monocropping.

When there's no diversity in a huge commercial crop, it becomes an easy target for pathogens.

Virulence of the banana wilt-causing fungal pathogen Fusarium oxysporum tropical race 4 is mediated by nitric oxide biosynthesis and accessory genes, Nature Microbiology (2024). DOI: 10.1038/s41564-024-01779-7

Comment by Dr. Krishna Kumari Challa on August 17, 2024 at 7:57am

Entanglement means the two-photon state is not a classical combination of two photon states. Instead, measuring or interacting with one of the photons instantly affects the same property of the second photon, no matter how far away it is.
Entanglement has been demonstrated for a system whose members are over 1,000 km apart. Nothing like it exists in classical physics; it is purely a quantum phenomenon. Here entanglement would raise the possibility of much faster signaling along the sections of myelin that encase segments of the axon's length.

One possibility, the authors write, is that the entanglement of photons could transform into entanglement along potassium ion channels in the neuron. If so, the opening and closing of one channel may affect the performance of another somewhere else.
These results are a combination of two phenomena that exist but are still largely mysterious: consciousness (let alone quantum consciousness) and quantum entanglement.
the researchers didn't say there is a direct connection. At this early stage, their primary goal is to identify possible mechanisms of neural synchronization, which affects numerous neurobiological processes. Through this work, they hope to gain a better understanding.

Zefei Liu et al, Entangled biphoton generation in the myelin sheath, Physical Review E (2024). DOI: 10.1103/PhysRevE.110.024402. On arXiv: DOI: 10.48550/arxiv.2401.11682

Part 3

Comment by Dr. Krishna Kumari Challa on August 17, 2024 at 7:54am

To remedy this problem, researchers investigated if there could be entangled photons within this axon-myelin system that could, though the magic of quantum entanglement, communicate instantly across the involved distances.
A tricarboxylic acid cycle releases energy stored in nutrients, with a cascade of infrared photons released during the cycling process. These photons couple to vibrations from carbon-hydrogen (C-H) bonds in lipid molecules and excite them to a higher vibrational energy state. As the bond then transitions to a lower vibrational energy state, it releases a cascade of photons.

The researchers applied cavity quantum electrohydrodynamics to a perfect cylinder surrounded by the myelin, making the reasonable assumption that the outer wall of the myelin sheath is a perfectly cylindrical conducting wall.
Using quantum mechanical techniques, they quantized the electromagnetic fields and the electric field inside the cavity, as well as the photons—that is, treated them all as quantum objects—and then, with some simplifying assumptions, solved the resulting equations.

Doing so gave the wavefunction for the system of the two photons interacting with the matter inside the cavity. They then calculated the photons' degree of entanglement by determining its quantum entropy, a measure of disorder, using an extension of classical entropy developed by the science polymath John von Neumann.
The researchers showed that the two photons can indeed have higher rate of being entangled under occasions.
The conducting wall limits the electromagnetic wave modes that can exist inside the cylinder, making the cylinder an electromagnetic cavity that keeps most of its energy within it. These modes are different from the continuous electromagnetic waves ("light") that exist in free space.

It is these discrete modes that result in the frequent production of highly entangled photons within the myelin cavity, whose rate of production can be significantly enhanced compared to two untangled photons.
Part 2

Comment by Dr. Krishna Kumari Challa on August 17, 2024 at 7:51am

Photon entanglement could explain the rapid brain signals behind consciousness

Understanding the nature of consciousness is one of the hardest problems in science. Some scientists have suggested that quantum mechanics, and in particular quantum entanglement, is the key to unraveling the phenomenon.

Now, a research group in China has shown that many entangled photons can be generated inside the myelin sheath that covers nerve fibers. It could explain the rapid communication between neurons, which so far has been thought to be below the speed of sound, too slow to explain how the neural synchronization occurs.

The paper is published in the journal Physical Review E.

The brain communicates within itself by firing electrical signals called synapses between neurons, which are the main components of nervous tissue. It is the synchronized activity of millions of neurons that consciousness (among other brain business) relies on. But the way this precise synchronization takes place is unknown.

Connections between neurons are called axons—long structures akin to electrical wires—and covering them is a coating ("sheath") made of myelin, a white tissue made of lipids.

Comprised of up to hundreds of layers, myelin insulates the axons, as well as shaping them and delivering energy to the axons. (In actuality, a series of such sheaths stretches across the length of the axon. The myelin sheath is typically about 100 microns long, with 1 to 2 micron gaps between them.) Recent evidence suggests myelin also plays an important role in promoting synchronization between neurons.

But the speed at which signals propagate along the axons is below the speed of sound, sometimes much below—too slow to create the millions of neuron synchronizations that are the basis for all the amazing things the brain can do.

Part 1

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