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Comment by Dr. Krishna Kumari Challa on August 9, 2023 at 9:55am

Brain's 'appetite control center' found to be different in people who are overweight or living with obesity

Scientists have shown that the hypothalamus, a key region of the brain involved in controlling appetite, is different in the brains of people who are overweight and people with obesity when compared to people who are a healthy weight.

The researchers say their findings add further evidence to the relevance of brain structure to weight and food consumption.

A large number of factors influence how much we eat and the types of food we eat, including our genetics, hormone regulation, and the environment in which we live. What happens in our brains to tell us that we are hungry or full is not entirely clear, though studies have shown that the hypothalamus, a small region of the brain about the size of an almond, plays an important role.

Researchers  used an algorithm developed using machine learning to analyze MRI brain scans taken from 1,351 young adults across a range of BMI scores, looking for differences in the hypothalamus when comparing individuals who are underweight, healthy weight, overweight and living with obesity.

In a study published in Neuroimage: Clinical, the scientists found that the overall volume of the hypothalamus was significantly larger in the overweight and obese groups of young adults. In fact, they found a significant relationship between volume of the hypothalamus and body-mass index(BMI).

These volume differences were most apparent in those sub-regions of the hypothalamus that control appetite through the release of hormones to balance hunger and fullness.

While the precise significance of the finding is unclear—including whether the structural changes are a cause or a consequence of the changes in body weight—one possibility is that the change relates to inflammation. Previous animal studies have shown that a high fat diet can cause inflammation of the hypothalamus, which in turn prompts insulin resistance and obesity.

Part 1

Comment by Dr. Krishna Kumari Challa on August 8, 2023 at 11:09am

Mosquito-dwelling microbe stops malaria
Malaria-carrying mosquitoes are less likely to pass on the parasite that causes the disease if they are infected with a naturally occurring bacterium. The microbe secretes a chemical that hobbles the malaria parasite’s development in the insects’ guts. So far, researchers trying to prevent the spread of the disease have had to rely on genetically modified bacteria — a major obstacle to regulatory and public acceptance, says malaria researcher Carolina Barillas-Mury. In experiments, one-third of mice bitten by bacterium-carrying mosquitoes became infected, compared with 100% of those bitten by regular malaria mosquitoes. And the mosquitoes don’t seem to develop resistance against the bacterium as they do to insecticides. The approach “has great potential to be implemented”.

 https://www.science.org/doi/10.1126/science.adf8141

Comment by Dr. Krishna Kumari Challa on August 8, 2023 at 10:44am

Scientists observe first evidence of 'quantum superchemistry' in the laboratory

A research team  has announced the first evidence for "quantum superchemistry"—a phenomenon where particles in the same quantum state undergo collective accelerated reactions. The effect had been predicted, but never observed in the laboratory till now.

The findings, published July 24 in Nature Physics, open the door to a new field. Scientists are intensely interested in what are known as "quantum-enhanced" chemical reactions, which could have applications in quantum chemistry, quantum computing, and other technologies, as well as in better understanding the laws of the universe.

Near absolute zero, particles can link up so that they are all in the same quantum state—where they can display unusual abilities and behaviors. It had been theorized that a group of atoms and molecules in the same quantum state would behave differently during chemical reactions, but the difficulty in orchestrating the experiment meant it had never been observed.

In the experiments, the scientists cooled down cesium atoms and coaxed them into the same quantum state. Next, they watched as the atoms reacted to form molecules. In ordinary chemistry, the individual atoms would collide, and there's a probability for each collision to form a molecule. However, quantum mechanics predicts that atoms in a quantum state perform actions collectively instead. You are no longer treating a chemical reaction as a collision between independent particles, but as a collective process. All of them are reacting together, as a whole.

One consequence is that the reaction happens faster than it would under ordinary conditions. In fact, the more atoms in the system, the faster the reaction happens.

Another consequence is that the final molecules share the same molecular state.

the same molecules in different states can have different physical and chemical properties —but there are times when you want to create a batch of molecules in a specific state. In traditional chemistry, you're rolling the dice. But with this technique, you can steer the molecules into an identical state.

Researchers  saw evidence that the reaction was taking place as a three-body interaction more often than as a two-body interaction. That is, three atoms would collide; two would form a molecule, and the third remained single. But the third played some role in the reaction.

 Zhendong Zhang et al, Many-body chemical reactions in a quantum degenerate gas, Nature Physics (2023). DOI: 10.1038/s41567-023-02139-8

Comment by Dr. Krishna Kumari Challa on August 8, 2023 at 10:22am

Therefore, linking this increased and consistent supply of methane to the Late Paleozoic Ice Age, which had a peak in atmospheric methane 304 million years ago, may suggest that the combined contribution from numerous alkaline lakes globally could have had a significant impact on global greenhouse gas levels. The researchers suggest that, taking the lakes in northwest China alone, methane emissions could have reached 109 gigatonnes, which is equivalent to the greenhouse forcing power of up to 7521 gigatonnes of carbon dioxide.

Clearly this highlights the potency of methane in affecting our climate, and specifically the importance of identifying alkaline lakes globally to monitor their current emissions and find solutions to help combat their activity. This can include reducing the pH of the lakes so that they become more acidic, adding certain types of clay or even dredging the lake bottom, but all of these solutions naturally introduce a host of their own effects on the environment. As such, there may not yet be a clear solution to reducing methane emissions from lakes and abating their global warming potential.

Liuwen Xia et al, Effects on global warming by microbial methanogenesis in alkaline lakes during the Late Paleozoic Ice Age (LPIA), Geology (2023). DOI: 10.1130/G51286.1

Part 2

Comment by Dr. Krishna Kumari Challa on August 8, 2023 at 10:21am

Ancient lake microbes caused global warming during ice age

Global warming is not just a modern issue, but has occurred numerous times over Earth's history, with one such event happening 304 million years ago during the Late Paleozoic Ice Age (which spanned from 340 to 290 million years ago). Studies have discovered evidence of increased sea surface temperature, continental ice decline and oceanic environments flooding the land at the time.

Scientists researched the effect of a large injection of methane from alkaline lakes (pH 9 to 12) into the atmosphere, in work published in Geology.

Large quantities of atmospheric methane causes global warming as it is a potent greenhouse gas trapping heat 28 times more effectively than carbon dioxide over 100 years. Methane-producing microorganisms are responsible for 74% of global methane emissions, therefore defining the environmental conditions that encourage them to not only survive but thrive is important for understanding climate change.

The Junggar Basin in northwest China was investigated by assessing methane levels derived from microbial activity. The researchers took core samples from the lake bed and undertook chemical analyses of the rock to determine the type of carbon present based upon its source from aquatic green algae, cyanobacteria (photosynthesising microorganisms) and halophilic archaea (an extreme microorganisms that lives in high salt environments). When the lake contains more dissolved inorganic carbon (a form that doesn't have carbon and hydrogen bonds) the algae, cyanobacteria and archaea preferentially take up the lighter form (carbon-12) meaning the heavier carbon-13 remains in the lake water and is deposited, leading to distinct differences in the measurements taken from the rock. The researchers found one particular type, alkalophilic methanogenic archaea, took a competitive advantage in the low sulfate anoxic environmental conditions of the lake, preserving the heaviest carbon-13 values in the rock. This species thrived by obtaining the energy required for growth by producing large quantities of methane in the lake water, which was then released into the atmosphere. Methane emissions from microbial activity alone are suggested to have been up to 2.1 gigatons. Carbon dioxide derived from volcanic activity and hydrothermal processes transported to the lake was converted into bicarbonate and carbonate (forms of dissolved inorganic carbon), which increased the alkalinity of the lake and is noted to enhance the creation of methane as it promotes microbial activity. Dissolved inorganic carbon provides an almost limitless supply of carbon to the algae, cyanobacteria and archaea for their metabolic processes.

Part 1

Comment by Dr. Krishna Kumari Challa on August 7, 2023 at 9:47am

For the first time researchers restore feeling and lasting movement in man living with quadriplegia

In a first-of-its-kind clinical trial, bioelectronic medicine researchers, engineers and surgeons  have successfully implanted microchips into the brain of a man living with paralysis, and have developed artificial intelligence (AI) algorithms to re-link his brain to his body and spinal cord.

This double neural bypass forms an electronic bridge that allows information to flow once again between the man's paralyzed body and brain to restore movement and sensations in his hand with lasting gains in his arm and wrist outside of the laboratory. The research team unveiled the trial participant's groundbreaking progress four months after a 15-hour open-brain surgery that took place on March 9 at North Shore University Hospital (NSUH).

This is the first time the brain, body and spinal cord have been linked together electronically in a paralyzed human to restore lasting movement and sensation.

When the study participant thinks about moving his arm or hand, researchers 'supercharge' his spinal cord and stimulate his brain and muscles to help rebuild connections, provide sensory feedback, and promote recovery. This type of thought-driven therapy is a game-changer. Their goal is to use this technology one day to give people living with paralysis the ability to live fuller, more independent lives.

Paralyzed from the chest down, Keith Thomas, 45, of Massapequa, NY, is the first human to use the technology. During the height of the pandemic, on July 18, 2020, a diving accident caused Mr. Thomas to suffer injury at the C4 and C5 level of the vertebrae in his spine, leaving him unable to move and feel from the chest down..

Now science has changed his fate!

Source: The Feinstein Institutes for Medical Research at Northwell Health

Comment by Dr. Krishna Kumari Challa on August 6, 2023 at 12:54pm

Multiwavelength Astronomy: The Big Picture

Comment by Dr. Krishna Kumari Challa on August 5, 2023 at 11:19am

Insulin-like hormones critical for brain plasticity, research suggests

Research has identified a mechanism through which insulin-like growth factors facilitate brain plasticity.

The insulin superfamily of hormones, including insulin, insulin-like growth factor 1 (IGF1), and insulin-like growth factor 2 (IGF2), play a crucial role not only in regulating blood sugar, metabolism, and growth, but also in healthy brain development and function, including learning and memory.

These hormones can enter the brain through the bloodstream from the liver or can be synthesized directly in neurons and glial cells within the brain. They bind to receptors, including the IGF1-receptor, activating signals that modulate neuron growth and activity. Disruption of this signaling pathway is involved in cognitive decline and diseases such as Alzheimer's.

In the present work one group of neurons in the hippocampus, CA1 neurons, produced IGF1; another group, CA3 neurons, produced IGF2. When either CA1 or CA3 neurons were activated in a way that mimicked synaptic plasticity, IGF wasreleased. Importantly, when the scientists disrupted the ability of the neurons to produce IGF, the activation of the IGF1-Receptor during plasticity and synaptic growth and strengthening was blocked.

This work reveals a local, autocrine mechanism in neurons that is critical forbrain plasticity. When a synapse undergoes plasticity, IGF is released locally to activate the IGF1-Receptor on the same neuron. Disrupting this mechanism impairs the plasticity, highlighting its critical role in maintaining cognitive health.

This discovery of this new mechanism sheds light on how memories are encoded in the brain and highlights the importance of further study on the insulin superfamily of hormones in the brain. 

 Xun Tu et al, Local autocrine plasticity signaling in single dendritic spines by insulin-like growth factors, Science Advances (2023). DOI: 10.1126/sciadv.adg0666

Comment by Dr. Krishna Kumari Challa on August 5, 2023 at 11:02am

Scientists discover how parasites of viruses drive superbug evolution

In a study published in Cell, scientists  have discovered a new way by which bacteria transmit their genes, enabling them to evolve much faster than previously understood.

The ability to share genetic material is the major driver of microbial evolution because it can transform a benign bacterium into a deadly pathogen in an instant. Phages, the viruses of bacteria, can act as conduits that allow genes to transfer from one bacterium to another by a process known as genetic transduction.

Currently, there are three known mechanisms of transduction: generalized, specialized, and lateral. Lateral transduction was also discovered by the same groups of researchers in 2018, and it is at least one thousand times more efficient than the next most powerful mechanism, generalized transduction.

The new process is termed lateral cotransduction, and the architects behind this new frequency and speed in bacterial evolution are the Staphylococcus aureus pathogenicity islands (SaPIs), which are selfish DNA elements that exploit and parasitise phages and are commonly found integrated into the chromosomes of S. aureus isolates.

S. aureus is a type of bacteria that can cause Staph infections in humans and animals. While it primarily manifests as skin infections, it can become life-threatening if it spreads to the bloodstream and infects organs, bones, or joints.

This newly-discovered process, lateral cotransduction, rivals lateral transduction in terms of efficiency but surpasses the latter in versatility and complexity. While lateral transduction is only known to occur when dormant phages within  bacterial genomesbecome reactivated and initiate reproduction in the lytic cycle, lateral cotransduction can occur during the reactivation process and the infection of new bacterial cells.

Additionally, unlike phages that sacrifice their genes to transmit bacterial host DNA, SaPIs can transfer themselves completely intact with bacterial DNA through lateral cotransduction. This remarkable capability enables them to perpetually repeat the process, making them significantly more potent and efficient in transmitting bacterial genes.

Through the study, scientists  have demonstrated that bacteria can evolve much faster than we understood.

This process likely occurs in various other bacterial species as well. This groundbreaking finding marks a paradigm shift in our understanding of bacterial evolution and will immensely influence the ways we combat antibiotic resistance.

They [phages] could be used to destroy bacteria in the short term but end up spreading harmful genes to other cells in the long term, which could prove to be disastrous. With this new way of understanding the evolutionary mechanisms of disease-causing organisms, it is important for therapeutic phages to be carefully vetted before they are used for therapy.

Melissa Su Juan Chee et al, Dual pathogenicity island transfer by piggybacking lateral transduction, Cell (2023). DOI: 10.1016/j.cell.2023.07.001

Comment by Dr. Krishna Kumari Challa on August 5, 2023 at 10:20am

The mechanisms of the relation between consuming more added sugars and a greater risk of developing kidney stones is not yet known. Because this was an uncontrolled observational trial, it can't yet be ruled out that unknown confounding factors might drive this association.

Further studies are needed to explore the association between added sugar and various diseases or pathological conditions in detail. For example, what types of kidney stones are most associated with added sugar intake? How much should we reduce our consumption of added sugars to lower the risk of kidney stone formation? Nevertheless, these  findings already offer valuable insights for decision-makers.

 Association between added sugars and kidney stones in US adults: data from National Health and Nutrition Examination Survey 2007-2018, Frontiers in Nutrition (2023). DOI: 10.3389/fnut.2023.1226082 , www.frontiersin.org/articles/1 … ut.2023.1226082/full

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