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Comment by Dr. Krishna Kumari Challa on October 29, 2023 at 12:29pm

We can't defeat cancer without acknowledging the differences between men and women, say scientists
For generations, the medical community has used the "standard human"—a 70-kilogram male—to guide education, research and practice. This means that for many conditions, although the recommended type, dosage and duration of treatment may be effective for the group of males who happen to weigh close to 70 kg, they might be far from optimal for most of the population, including all females.

In cancer, multiple bodily factors contribute to how the disease develops, progresses and responds to treatment, and many of these factors relate to sex.

Sex differences in cancer are not technically a new insight, but they have historically been somewhat overlooked. However, researchers have recently started to uncover some of the mechanisms behind how a person's sex affects their experience of cancer. The realization that such knowledge may one day make it possible to improve outcomes for all patients has given more scientists the impulse to delve deeper into this area of research.
The anatomical differences between males and females are well known. Males typically have higher muscle and bone mass, a lower fat mass and a visibly different skeletal shape. Males also have a higher body water content, which, alongside differences in metabolism and fat mass, can affect how the body responds to and breaks down cancer-killing drugs.

Some of these differences are due to males having one Y chromosome and one X chromosome, rather than the two X chromosomes in the female body. In fact, research suggests that genetics plays a very significant part, indicating that up to one third of the genome might be expressed differently by males and females.

Females and males also have different sex hormones, and these influence the blood vessels, immune cells, signaling molecules and other features that surround tumors, known as the tumor microenvironment. For types of cancer that are dependent on or sensitive to hormones, these chemicals can promote the growth and spread of the disease.

Researchers have also uncovered differences between male and female immune responses. They believe that these are typically stronger in females, who tend to clear disease-causing organisms such as bacteria more quickly from the body and be better protected by vaccinations. Conversely, females are often more susceptible to inflammatory and autoimmune conditions, some of which are associated with an increased risk of cancer.

All of these differences mean that, although males are more likely than females to get cancer and to have a poor outcome, females are 34 percent more likely to experience side effects from cancer treatments, including chemotherapy, targeted therapy and immunotherapy.
A big part of the problem is that treatment recommendations are based on the findings of clinical trials, which are only generalizable if the trial participants are representative of the relevant patient population. This is an issue because females are generally under-represented in clinical trials.
Part 1

Comment by Dr. Krishna Kumari Challa on October 29, 2023 at 12:09pm

However, nature is chaotic, and not all physical systems are bound by these symmetries. So-called non-reciprocal interactions show up in unruly systems made up of flocking birds, particles in fluid – and swimming sperm.

These motile agents move in ways that display asymmetric interactions with the animals behind them or the fluids that surround them, forming a loophole for equal and opposite forces to skirt Newton's third law.
Because birds and cells generate their own energy, which gets added to the system with each flap of their wings or whip of their tails, the system is thrust far from equilibrium, and the same rules don't apply.
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Scientists analyzed experimental data on human sperm and also modeled the motion of green algae, Chlamydomonas. Both swim using thin, bendy flagella that protrude from the cell body and change shape, or deform, to drive the cells forward.

Highly viscous fluids would typically dissipate a flagellum's energy, preventing a sperm or single-celled algae from moving much at all. And yet somehow, the elastic flagella can propel these cells along without provoking a response from their surroundings.

The researchers found that sperm tails and algal flagella have an 'odd elasticity', which allows these flexible appendages to whip about without losing much energy to the surrounding fluid.
But this property of odd elasticity didn't fully explain the propulsion from the flagella's wave-like motion. So from their modeling studies, the researchers also derived a new term, an odd elastic modulus, to describe the internal mechanics of flagella.
The findings could help in the design of small, self-assembling robots that mimic living materials, while the modeling methods could be used to better understand the underlying principles of collective behaviour.

https://journals.aps.org/prxlife/abstract/10.1103/PRXLife.1.023002

Part 2

Comment by Dr. Krishna Kumari Challa on October 29, 2023 at 12:06pm

Scientists Caught Sperm Defying One of The Major Laws of Physics

With their whip-like tails, human sperm propel themselves through viscous fluids, seemingly in defiance of Newton's third law of motion, according to a new study that characterizes the motion of these sex cells and single-celled algae.

Scientists investigated these non-reciprocal interactions in sperm and other microscopic biological swimmers, to figure out how they slither through substances that should, in theory, resist their movement.

When Newton conceived his now-famed laws of motion in 1686, he sought to explain the relationship between a physical object and the forces acting upon it with a few neat principles that, it turns out, don't necessarily apply to microscopic cells wriggling through sticky fluids.

Newton's third law can be summed up as "for every action, there is an equal and opposite reaction". It signifies a particular symmetry in nature where opposing forces act against each other. In the simplest example, two equal-sized marbles colliding as they roll along the ground will transfer their force and rebound based on this law.

However, nature is chaotic, and not all physical systems are bound by these symmetries. So-called non-reciprocal interactions show up in unruly systems made up of flocking birds, particles in fluid – and swimming sperm.

These motile agents move in ways that display asymmetric interactions with the animals behind them or the fluids that surround them, forming a loophole for equal and opposite forces to skirt Newton's third law.
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Part 1

Comment by Dr. Krishna Kumari Challa on October 29, 2023 at 11:44am

Scientists Unveil World-First Experimental Cocaine Addiction Vaccine

Scientists  have announced the development of an innovative new treatment for addiction to the drug and its powerful derivative crack: a vaccine.

Dubbed "Calixcoca," the test vaccine, which has shown promising results in trials on animals, triggers an immune response that blocks cocaine and crack from reaching the brain, which researchers hope will help users break the cycle of addiction.

Put simply, addicts would no longer get high from the drug.

​If the treatment gets regulatory approval, it would be the first time cocaine addiction is treated using a vaccine.

​The vaccine works by triggering patients' immune systems to produce antibodies that bind to cocaine molecules in the bloodstream, making them too large to pass into the brain's mesolimbic system, or "reward center," where the drug normally stimulates high levels of pleasure-inducing dopamine.

​It also protected rat fetuses against cocaine, researchers found, suggesting it could be used in humans to protect the unborn babies of pregnant addicts.

​The vaccine is now set to enter the final stage of trials: testing on humans.

​The vaccine is made with chemical compounds designed in the lab, rather than biological ingredients, meaning it would be less expensive to produce than many vaccines and would not have to be stored at cold temperatures.​

Source: AFP

Comment by Dr. Krishna Kumari Challa on October 28, 2023 at 9:50am

Microgravity Can Permanently Mutate Bacteria And Make Them Faster Breeders

Certain types of bacteria can mutate to reproduce more quickly when exposed to microgravity, and that's not great news for our space tourist dreams, seeing as we humans are teeming with bacteria. It's not clear why these bacteria respond so positively to microgravity, but researchers are figuring out ways to protect astronauts out in space, as well as mitigating the damage should a space-modified colony ever find its way back to Earth. In a study published in 2017, researchers from the University of Houston monitored Escherichia coli cells through 1,000 generations of growth in simulated microgravity conditions, finding that it spread significantly faster than a control sample of unaltered bacteria. The E. coli cells also picked up at least 16 different genetic mutations along the way, though it's not clear how these mutations affect growth rates, either individually or as a group. The adapted cells grew about three times as many colonies as the unmodified E. coli, the tests showed. Even when the supercharged bacteria were removed from microgravity conditions up to 30 generations before testing, 72 percent of the growth advantage was retained, showing that some changes prompted by space travel could be permanent. Certain strains have previously been shown to grow 60 percent more quickly in microgravity, so there seems to be something about that weightless environment that these microorganisms really like. Even now, astronauts on board the ISS are having to deal with thick biofilms of bacteria on their equipment that are growing faster than normal.

https://www.nature.com/articles/s41526-017-0020-1

Comment by Dr. Krishna Kumari Challa on October 28, 2023 at 9:24am

Inside CERN’s ‘antimatter factory’ creating antihydrogen

Comment by Dr. Krishna Kumari Challa on October 27, 2023 at 7:34am

Mimics human tissue, fights bacteria: new biomaterial

Scientists have created a new material that could change the way human tissue can be grown in the lab and used in medical procedures.

The new material belongs to a family of substances called hydrogels, the essence of life’s ‘squishy’ substances found in all living things, such as cartilage in animals and in plants like seaweed. The properties of hydrogels make them very useful in biomedical research because they can mimic human tissue, allowing cells to grow in a laboratory.

There are also human-made hydrogels that are used in a broad range of commodity products ranging from food and cosmetics to contact lenses and absorbent materials, and more recently in medical research to seal wounds and replace damaged tissue. While they might function adequately as space fillers that encourage tissue growth, synthetic hydrogels fall short in recreating the complex properties of real human tissue.

But in a research paper published today in Nature Communications, scientists describe how a new lab-made hydrogel behaves like natural tissue, with a number of surprising qualities that have implications for medical, food and manufacturing technology.

The hydrogel material is made from very simple, short peptides, which are the building blocks of proteins. The material is bioactive, which means that encapsulated cells behave as if they are living in natural tissue. At the same time, the material is antimicrobial, meaning that it will prevent bacterial infections. This combination lands it in the sweet spot for materials that might be useful in medicine. The material is also self-healing, which means that it will reform after being squished, fractured, or after being expelled from a syringe. This makes it ideal for 3D bioprinting, or as an injectable material for medicine.

https://www.nature.com/articles/s41467-023-41907-1

Comment by Dr. Krishna Kumari Challa on October 25, 2023 at 10:01am

Biological fingerprints in soil show where diamond-containing ore is buried

Researchers have identified buried kimberlite, the rocky home of diamonds, by testing the DNA of microbes in the surface soil.

These "biological fingerprints" can reveal which minerals are buried tens of meters below Earth's surface without having to drill. The researchers believe it is the first use of modern DNA sequencing of microbial communities in the search for buried minerals.

The research published in Communications Earth and Environment represents a new tool for mineral exploration, where a full toolbox could save prospectors time and a lot of money.

When ore interacts with soil, it changes the communities of microbes in the soil. The researchers tested this in the lab, introducing kimberlite to soil microbes and watching how they changed in number and species.

Using these "indicator" microbes and their DNA sequences, the team tested the surface soil at an exploration site in the Northwest Territories where kimberlite had previously been confirmed through drilling. They found 59 of the 65 indicators were present in the soil, with 19 present in high numbers directly above the buried ore. They also identified new indicator microbes to add to their set.

Using this set, they tested the surface soil at a second site in the Northwest Territories where they suspected kimberlite was present, and precisely located the topological outline and location of kimberlite buried tens of meters beneath the Earth's surface. This showed that indicators from one site could predict the location at another site. In future, exploration teams could build up a database of indicator species and test an unknown site to find out if kimberlite deposits are buried beneath the soil.

The researchers evaluated their technique against another technique known as geochemical analysis, which involves testing elements in the soil to identify the minerals beneath. The microbes were more precise when it came to identifying the location of buried ore.

Rachel L. Simister et al, DNA sequencing, microbial indicators, and the discovery of buried kimberlites, Communications Earth & Environment (2023). DOI: 10.1038/s43247-023-01020-z

Comment by Dr. Krishna Kumari Challa on October 23, 2023 at 10:04am

Comment by Dr. Krishna Kumari Challa on October 23, 2023 at 9:30am

Two probiotics identified as promising hypertension treatments

An estimated 40% of the global adult population have high blood pressure, or hypertension, which puts people at risk of cardiovascular disease and other dangerous health conditions. Recent studies suggest that probiotics may offer a protective effect, but researchers have a limited understanding of why shaping the gut microbiota can regulate blood pressure.

A study published in mSystems adds two new strains to the list of potential antihypertensive probiotics.

In experiments on hypertensive mice, treatment with the two probiotics, Bifidobacterium lactis and Lactobacillus rhamnosus, returned blood pressure to normal levels. The researchers also tracked how those probiotics altered the animals' gut microbial mix over 16 weeks, identifying specific microbes and metabolic pathways that may help explain the protective effect.

Accumulated evidence supports an antihypertensive effect of probiotics and probiotic fermented foods in both in vitro and in vivo experiments

Previous studies have connected the rising rates of hypertension worldwide to increasing consumption of sugar. It likely boosts blood pressure through many mechanisms—increased insulin resistance or salt retention, for example—but in recent years researchers have investigated sugar's effect on the gut microbiome, as well.

In the new study, the researchers tested the two probiotic strains on mice that developed high blood pressure after consuming water mixed with fructose. Over 16 weeks, they measured the animals' blood pressures every four weeks. They found that fructose-fed mice that received either probiotic showed significantly lower blood pressures than those fed a high fructose diet and not treated with probiotics.

The researchers used shotgun metagenomic sequencing to probe connections between the altered gut microbiota and the change in blood pressure. They found that a high-fructose diet in the mice led to an increase in Bacteroidetes and a decrease in Firmicutes bacteria; however, treatment with probiotics returned those populations to those found in the control group. In addition, the analysis identified new microbial signatures associated with blood pressure: Increased levels of Lawsonia and Pyrolobus bacteria, and reduced levels of Alistipes and Alloprevotella, were associated with lower blood pressure.

 mSystems (2023). journals.asm.org/doi/10.1128/msystems.00331-23

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