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Comment by Dr. Krishna Kumari Challa on May 24, 2024 at 12:41pm

How gut microbes drive tumour growth
Scientists have long known that obese people have poorer cancer survival rates. Now they have some idea why. A high-fat diet increases the number of Desulfovibrio bacteria in the gut of mice. These release leucine, an amino acid, which encourages the proliferation of a kind of cell that suppresses the immune system. With a suppressed immune system, tumour growth can increase. In breast cancer patients, poorer outcomes were seen for women with higher body-mass index, who also had higher levels of Desulfovibrio bacteria in their gut and leucine in their blood. It’s a provocative finding that will open up new avenues that we should be thinking about.

https://www.pnas.org/doi/10.1073/pnas.2306776121?utm_source=Live+Au...

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Biggest risk factors for disease spread A meta-analysis of five ways that humanity’s environmental footprint spreads disease — biodiversity loss, chemical pollution, climate change, invasive species and deforestation/urbanization — suggests that conserving biodiversity, controlling invasive species and lowering greenhouse-gas emissions would reduce disease spread the most. This evidence can be used in international policy to spur action on climate change and biodiversity loss due to their negative impacts on disease.

https://www.nature.com/articles/s41586-024-07380-6?utm_source=Live+...

Comment by Dr. Krishna Kumari Challa on May 24, 2024 at 11:52am

Micro-ballistics research has shown metals hardening as they are heated, under extreme strain rates.

Comment by Dr. Krishna Kumari Challa on May 24, 2024 at 11:39am

Strange  bacteria defy textbooks by writing new genes

Bacterial defensive systems scramble the standard workflow of life.

Genetic information usually travels down a one-way street: genes written in DNA serve as the template for making RNA molecules.... That tidy textbook story got a bit complicated in 1970 when scientists discovered that some viruses have enzymes called reverse transcriptases, which scribe RNA into DNA — the reverse of the usual traffic flow.

Now, scientists have discovered an even weirder twist. A bacterial version of reverse transcriptase reads RNA as a template to make completely new genes written in DNA. These genes are then transcribed back into RNA, which is translated into protective proteins when a bacterium is infected by a virus. By contrast, viral reverse transcriptases don’t make new genes; they merely transfer information from RNA to DNA.

This is a crazy molecular biology!

https://www.nature.com/articles/d41586-024-01477-8?utm_source=Live+...

Part 2

The discovery that reverse transcriptase — which has previously been known only for copying genetic material — can create completely new genes has left other researchers gobsmacked.

Comment by Dr. Krishna Kumari Challa on May 24, 2024 at 11:37am

Bizarre bacteria scramble workflow of life
Bacteria have stunned biologists by reversing the usual flow of information. Typically genes written in DNA serve as the template for making RNA molecules, which are then translated into proteins. Some viruses are known to have an enzyme that reverses this flow by scribing RNA into DNA. Now scientists have found bacteria with a similar enzyme that can even make completely new genes — by reading RNA as a template. These genes create protective proteins when a bacterium is infected by a virus. It should change the way we look at the genome.

https://www.biorxiv.org/content/10.1101/2024.05.08.593200v1

Part 1

Comment by Dr. Krishna Kumari Challa on May 24, 2024 at 11:18am

Atomic-resolution imaging shows why ice is so slippery

A team of physicists  has uncovered the reason behind the slipperiness of ice. In their study, published in the journal Nature, the group used atomic force microscopy to get a closer look at the surface of ice at different temperatures.

Prior research and day-to-day experiences  have shown that ice is slippery, even when temperatures are well below the freezing point. Research has suggested this is because of a pre-melt coating that develops at the surface, which serves as a lubricant.

In this new study, the research team used an atomic force microscope fitted with a carbon monoxide atom on its tip to get a better look at the structure of normal ice and its pre-melt coating.

The researchers began by chilling ice inside the microscope chamber to -150°C and then using the microscope to look at its atomic structure. They could see that the internal ice (known as ice Ih), and the ice at the surface were different.

The ice Ih, as expected, was arranged in stacked hexagons. The ice on the surface, by contrast, was only partially hexagonal. The researchers also found defects in the ice at the border between the two types of ice that occurred as the different ice shapes met one another.

The researchers then raised the temperature in the chamber slightly, which resulted in more disorder as the differences in shape became more pronounced. The team then created a simulation showing how such disorder would impact the surface as a whole unit—it showed the disorder expanding all the way across the surface, giving the ice a liquid-like appearance that would be slippery if trod upon.

 Jiani Hong et al, Imaging surface structure and premelting of ice Ih with atomic resolution, Nature (2024). DOI: 10.1038/s41586-024-07427-8

Comment by Dr. Krishna Kumari Challa on May 24, 2024 at 11:05am

And the team think that the new device could help speed up the search for notoriously elusive particles known as axions, which are so far only theoretical, but proposed by many as the secret ingredient of mysterious dark matter.

 The squeezed noise itself could even be used in future quantum computers.

It turns out that squeezed vacuum noise is an ingredient to build a certain type of quantum computer. Excitingly, the level of squeezing they've achieved is not far off the amount needed to build such a system.

 Arjen Vaartjes et al, Strong microwave squeezing above 1 Tesla and 1 Kelvin, Nature Communications (2024). DOI: 10.1038/s41467-024-48519-3

Part 2

Comment by Dr. Krishna Kumari Challa on May 24, 2024 at 11:05am

How a world record 'squeeze' could offer comfort for dark matter hunters

Quantum engineers have developed a new amplifier that could help other scientists search for elusive dark matter particles.

Imagine throwing a ball. You'd expect science to be able to work out its exact speed and location at any given moment, right? Well, the theory of quantum mechanics says you can't actually know both with infinite precision at the same time.

It turns out that as you more precisely measure where the ball is, knowing its speed becomes less and less accurate.

This conundrum is commonly referred to as Heisenberg's uncertainty principle, named after the famous physicist Werner Heisenberg who first described it.

For the ball, this effect is imperceptible, but in the quantum world of small electrons and photons the measurement uncertainty suddenly becomes very significant.

That's the problem being addressed by a team of engineers who have developed an amplifying device that performs precise measurements of very weak microwave signals, and it does so through a process known as squeezing.

Squeezing involves reducing the certainty of one property of a signal in order to obtain ultra-precise measurements of another property.

The team of researchers  have significantly increased the accuracy of measuring signals at microwave frequencies, like those emitted by your mobile phone, to the point of setting a new world record.

The precision of measuring any signal is fundamentally limited by noise. Noise is the fuzziness that creeps in and masks signals, which is something you may have experienced if you've ever ventured out of range when listening to AM or FM radio.

However, uncertainty in the quantum world means there is a limit as to how low noise can be made in a measurement. 

Even in a vacuum, a space void of everything, the uncertainty principle tells us we must still have noise. We call this 'vacuum' noise. For many quantum experiments, vacuum noise is the dominant effect that prevents us from making more precise measurements.

The squeezer produced by the research team now can beat this quantum limit.

The device amplifies noise in one direction, so that noise in another direction is significantly reduced, or 'squeezed.' Think of the noise as a tennis ball, if we stretch it vertically, then it must reduce along the horizontal to maintain its volume. Researchers  can then use the reduced part of the noise to do more precise measurements.

They showed that the squeezer is able to reduce noise to record low levels.

Squeezing is very difficult at microwave frequencies because the materials used tend to destroy the fragile squeezed noise quite easily.

What they've done is a lot of engineering in order to remove sources of loss, which means utilizing very high-quality superconducting materials to build the amplifier.

Part 1

Comment by Dr. Krishna Kumari Challa on May 24, 2024 at 10:41am

Nanoparticle vaccines: A potential leap forward in veterinary medicine

Classical vaccines often rely on traditional technologies, such as live attenuated or inactivated pathogens, which carry inherent risks including reduced immunogenicity under certain conditions and potential safety concerns. This has spurred the need for innovative approaches that can provide safer and more effective prophylactic solutions in veterinary medicine.

Self-assembled protein nanoparticles (SAPNs) emerge as a cutting-edge solution, harnessing the power of nanotechnology to revolutionize vaccine design and implementation.

In an article published on 10 May 2024 in Animal Diseases, researchers at Zhejiang University's Institute of Preventive Veterinary Medicine, delve into the development and application of SAPNs and virus-like nanoparticles (VLPs), offering a detailed discussion of their potential in veterinary medicine.

The article focuses on various types of SAPNs, including natural and synthetically designed nanoparticles. These nanoparticles are tailored to enhance the immune system's ability to recognize and respond to pathogens more effectively.

Key highlights include the use of animal virus-derived nanoparticles and bacteriophage-derived nanoparticles, which have shown the potential to elicit strong cellular and humoral responses. The nanoparticles' ability to mimic pathogen structures enables them to trigger a more substantial immune reaction, potentially leading to long-lasting immunity.

Researchers have documented successes in using these nanoparticles to protect against diseases like foot-and-mouth disease and swine fever, showcasing their broad applicability and effectiveness.

Veterinary nanoparticle vaccines have broad implications, with the potential to extend the benefits beyond veterinary applications into human health. The enhanced safety and immunogenicity of these vaccines could lead to the development of advanced vaccines for human use.

Additionally, by reducing the environmental impact of livestock diseases, this technology may contribute to more sustainable agricultural practices globally.

Meiqi Sun et al, Toward innovative veterinary nanoparticle vaccines, Animal Diseases (2024). DOI: 10.1186/s44149-024-00119-w

Comment by Dr. Krishna Kumari Challa on May 24, 2024 at 10:02am

Why the brain can robustly recognize images, even without colour

Even though the human visual system has sophisticated machinery for processing colour, the brain has no problem recognizing objects in black-and-white images. A new study offers a possible explanation for how the brain comes to be so adept at identifying both colour and colour-degraded images.

Using experimental data and computational modeling, the researchers found evidence suggesting the roots of this ability may lie in development. The work has been published in Science

Early in life, when newborns receive strongly limited colour information, the brain is forced to learn to distinguish objects based on their luminance, or intensity of light they emit, rather than their colour. Later in life, when the retina and cortex are better equipped to process colours, the brain incorporates colour information as well but also maintains its previously acquired ability to recognize images without critical reliance on colour cues.

The findings also help to explain why children who are born blind but have their vision restored later in life, through the removal of congenital cataracts, have much more difficulty identifying objects presented in black and white. Those children, who receive rich colour input as soon as their sight is restored, may develop an overreliance on colour that makes them much less resilient to changes or removal of colour information.

Researchers  have observed that limitations in early sensory input can also benefit other aspects of vision, as well as the auditory system.

In 2022, they used computational models to show that early exposure to only low-frequency sounds, similar to those that babies hear in the womb, improves performance on auditory tasks that require analyzing sounds over a longer period of time, such as recognizing emotions. 

Marin Vogelsang et al, Impact of early visual experience on later usage of color cues, Science (2024). DOI: 10.1126/science.adk9587. www.science.org/doi/10.1126/science.adk9587

Comment by Dr. Krishna Kumari Challa on May 24, 2024 at 9:22am

Exposure to endocrine-disrupting chemicals in utero associated with higher odds of metabolic syndrome in children

The term 'metabolic syndrome' (MetS) encompasses a group of factors, such as abdominal obesity, hypertension and insulin resistance, that together increase the risk of cardiovascular disease and type 2 diabetes.

A new study suggests that prenatal exposure to a combination of endocrine disrupting chemicals (EDCs) is associated with poorer metabolic health in childhood, which in turn may contribute to an increased risk of metabolic syndrome in adulthood.

EDCs are chemical substances that are so named because of their ability to interfere with the functioning of our hormonal system, growth, energy balance and metabolism and whose exposure, given their ubiquity in our environment, is difficult to escape.

Previous studies have already shown a link between individual exposure to some of these compounds during the prenatal phase and some of the factors that make up the metabolic syndrome, particularly obesity and blood pressure.

The study involved 1,134 mothers and their children from six European countries (Spain, France, Greece, Lithuania, Norway and the United Kingdom), all volunteers from the HELIX (Human Early Life Exposome) cohort. Prenatal exposure to a total of 45 endocrine disruptors was analyzed through blood and urine samples collected from the mothers during pregnancy or from the umbilical cord after birth.

Later, when the children were between 6 and 11 years old, they were followed up, including a clinical examination, interview and collection of biological samples. This yielded data on waist circumference, blood pressure, cholesterol, triglycerides and insulin levels, which were aggregated to obtain a risk index for metabolic syndrome.

Statistical analysis showed that mixtures of metals, perfluoroalkylated and polyfluoroalkylated substances (PFAS), organochlorine pesticides and flame retardants (or PBDEs) were associated with a higher risk of metabolic syndrome. In the case of metals, the association observed was mainly due to the effect of mercury, the main source of which is the intake of large fish.

PFASs are one of the most widely used families of chemical compounds, being used in pesticides, paints, non-stick pans or fast food packaging, among many other common uses. Because of their persistence, they are also known as the "forever chemicals." Also very persistent are organochlorine pesticides, which were already banned in Europe in the 1970s, but to which we are still widely exposed due to their permanence in the environment.

Researchers also observed that associations were stronger in girls for mixtures of PFASs and polychlorinated biphenyls (PCBs), while boys were more susceptible to exposure to parabens. Since endocrine disruptors interfere with sex steroid hormones, these differences fall within what would be expected.

These results suggest that exposure to widespread mixtures of endocrine disruptors during pregnancy may be associated with adverse metabolic health in both boys and girls. This association may contribute to the current increase in the prevalence of lifetime metabolic syndrome, which currently affects a quarter of the adult population, with upward trends evident even among young people
 Prenatal Exposure to Chemical Mixtures and Metabolic Syndrome Risk in Children, JAMA Network Open (2024). DOI: 10.1001/jamanetworkopen.2024.12040

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