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Comment by Dr. Krishna Kumari Challa on May 24, 2022 at 7:01am

Study reveals evidence that bacteria can live in snake and spider venoms

Newly published research  shows that, contrary to what is commonly believed, the venom of snakes and spiders is actually populated with microbes, including bacteria that could cause infection in people who have suffered a bite.

For decades scientists have thought that animal venom is an entirely sterile environment due to it being full of antimicrobial substances—materials that can kill bacteria.

However, new scientific evidence from research has shown that this is not the case. 

The work, published today in scientific journal Microbiology Spectrum demonstrates how adaptable microorganisms are. The study provides strong genetic and culture evidence that bacteria can not only survive in the venom glands of several species of snakes and spiders, but can also mutate to resist the notoriously toxic liquid that is venom.

The findings also suggest that victims of venomous animal bites may therefore also need to be treated for infections, not just antivenom to tackle the toxins deposited through the bite.

Common diagnostic tools failed to identify these bacteria correctly—if you were infected with these, a doctor would end up giving you the wrong antibiotics, potentially making matters worse.

When researchers sequenced their DNA recently they clearly identified the bacteria and discovered they had mutated to resist the venom. This is extraordinary because venom is like a cocktail of antibiotics, and it is so thick with them, you would have thought the bacteria would not stand a chance. Not only did they stand a chance, they had done it twice, using the same mechanisms.

They also directly tested the resistance of Enterococcus faecalis, one of the species of bacteria they found in the venom of black-necked spitting cobras, to venom itself and compared it to a classic hospital isolate: the hospital isolate did not tolerate the venom at all, but the two isolates from venom  happily grew in the highest concentrations of venom researchers could throw at them.

The researchers say that their study shows the need for clinicians to consider treating snakebite victims not just for tissue destruction, but for infection too, as quickly as possible.

 Elham Esmaeilishirazifard et al, Bacterial Adaptation to Venom in Snakes and Arachnida, Microbiology Spectrum (2022). DOI: 10.1128/spectrum.02408-21. journals.asm.org/doi/10.1128/spectrum.02408-21

Comment by Dr. Krishna Kumari Challa on May 24, 2022 at 6:52am

Low-cost gel film can pluck drinking water from desert air

More than a third of the world's population lives in drylands, areas that experience significant water shortages. Scientists and engineers have developed a solution that could help people in these areas access clean drinking water.

Researchers now developed a low-cost gel film made of abundant materials that can pull water from the air in even the driest climates. The materials that facilitate this reaction cost a mere $2 per kilogram, and a single kilogram can produce more than 6 liters of water per day in areas with less than 15% relative humidity and 13 liters in areas with up to 30% relative humidity.

The research builds on previous breakthroughs from the team, including the ability to pull water out of the atmosphere and the application of that technology to create self-watering soil. However, these technologies were designed for relatively high-humidity environments.

This new work is about practical solutions that people can use to get water in the hottest, driest places on Earth. This could allow millions of people without consistent access to drinking water to have simple, water generating devices at home that they can easily operate.

The researchers used renewable cellulose and a common kitchen ingredient, konjac gum, as a main hydrophilic (attracted to water) skeleton. The open-pore structure of gum speeds the moisture-capturing process. Another designed component, thermo-responsive cellulose with hydrophobic (resistant to water) interaction when heated, helps release the collected water immediately so that overall energy input to produce water is minimized.

The film is flexible and can be molded into a variety of shapes and sizes, depending on the need of the user. Making the film requires only the gel precursor, which includes all the relevant ingredients poured into a mold.

The gel takes 2 minutes to set simply. Then, it just needs to be freeze-dried, and it can be peeled off the mold and used immediately after that.

Youhong Guo et al, Scalable super hygroscopic polymer films for sustainable moisture harvesting in arid environments, Nature Communications (2022). DOI: 10.1038/s41467-022-30505-2

Comment by Dr. Krishna Kumari Challa on May 24, 2022 at 6:38am

Some researchers are now  studying reversible chemistry, which is chemistry that allows bonds to self-correct, allowing for the creation of novel ordered structures, or lattices, such as synthetic DNA-like polymers.

Using a process called alkyne metathesis—which is an organic reaction that entails the redistribution, or cutting and reforming, of alkyne chemical bonds (a type of hydrocarbon with at least one carbon-carbon triple covalent bond)—as well as thermodynamics and kinetic control, the researchers were able to successfully create what had never been created before: A material that could rival the conductivity of graphene but with control.

This could be the next generation wonder material. 

While the material has been successfully created, the scientists still want to look into the particular details of it, including how to create the material on a large scale and how it can be manipulated.

Yiming Hu et al, Synthesis of γ-graphyne using dynamic covalent chemistry, Nature Synthesis (2022). DOI: 10.1038/s44160-022-00068-7

Part 2

Comment by Dr. Krishna Kumari Challa on May 24, 2022 at 6:35am

'Next generation wonder material' created for first time

For over a decade, scientists have attempted to synthesize a new form of carbon called graphyne with limited success. That endeavor is now at an end.

Graphyne has long been of interest to scientists because of its similarities to the "wonder material" graphene—another form of carbon that is highly valued by industry . 

However, despite decades of work and theorizing, only a few fragments have ever been created before now.

This research, announced last week in Nature Synthesis, fills a longstanding gap in carbon material science, potentially opening brand-new possibilities for electronics, optics and semiconducting material research.

Scientists have long been interested in the construction of new or novel carbon allotropes, or forms of carbon, because of carbon's usefulness to industry, as well as its versatility.

There are different ways carbon allotropes can be constructed depending on how sp2, sp3 and sp hybridized carbon (or the different ways carbon atoms can bind to other elements), and their corresponding bonds, are utilized. The most well-known carbon allotropes are graphite (used in tools like pencils and batteries) and diamonds, which are created out of sp2 carbon and sp3 carbon, respectively.

Using traditional chemistry methods, scientists have successfully created various allotropes over the years, including fullerene and graphene.

However, these methods don't allow for the different types of carbon to be synthesized together in any sort of large capacity, like what's required for graphyne, which has left the theorized material—speculated to have unique electron conducting, mechanical and optical properties—to remain that: a theory.

Part 1

Comment by Dr. Krishna Kumari Challa on May 23, 2022 at 11:53am

Drug treatment for cataracts moves a step closer

A revolutionary new treatment for cataracts has shown extremely positive results in laboratory tests, giving hope that the condition, which currently can only be cured with surgery, could soon be treated with drugs.

Cataract is a clouding of the eye lens that develops over time and affects the quality of vision. It is caused by a disorganization of the proteins in the lens that leads to clumps of protein forming, which scatter light and severely reduce transmission to the retina. Cataracts cause vision loss  and blindness for millions of people worldwide.

Scientists have  been carrying out advanced optical tests on an oxysterol compound that had been proposed as an anti-cataract drug.  In laboratory trials, treatment with the oxysterol compound VP1-001 showed an improvement in refractive index profiles—a key optical parameter that is needed to maintain high focusing capacity—in 61% of lenses. This means that the protein organization of the lens is being restored, resulting in the lens being better able to focus. This was supported by a reduction in lens opacity in 46% of cases.

It has shown that there is a remarkable difference and improvement in optics between eyes with the same type of cataract that were treated with the compound compared to those that were not.

"Improvements occurred in some types of cataract but not in all, indicating that this may be a treatment for specific cataracts. This suggests distinctions may need to be made between cataract types when developing anti-cataract medications. It is a significant step forward towards treating this extremely common condition with drugs rather than surgery.

Oxysterol compounds in mouse mutant αA- and αB-crystallin lenses 2 can improve the optical properties of the lens, Investigative Ophthalmology & Visual Science (2022).

Comment by Dr. Krishna Kumari Challa on May 23, 2022 at 6:56am

Male pheromones improve health of females' eggs

Male pheromones just might be the fountain of youth for aging female animals’ eggs, according to a new study.

In the new study, researchers used the tiny transparent roundworm C. elegans, a well-established model organism commonly used in biology research. Exposure of female roundworms to male pheromones slowed down the aging of the females’ egg cells, resulting in healthier offspring.

Not only did the exposure decrease embryonic death by more than twofold, it also decreased chromosomal abnormalities in surviving offspring by more than twofold. Under the microscope, egg cells also looked younger and healthier, rather than tiny and misshapen, which is common with aging.

To conduct the study, the team aged female roundworms in the presence of a pheromone that is normally produced by male roundworms. The researchers saw that egg quality in females exposed to the pheromone was higher than in control roundworms that did not encounter the pheromone.

Although continuous exposure to male pheromones worked best, even shorter exposure improved overall egg quality. Researchers think this result can be explained by the animals’ “shifting energy budgets.”

Acting outside the body, pheromones are chemicals that animals produce and release to elicit social responses from other members of their species. Pheromones also inform animals about how to budget their finite energy.

When conditions are not conducive to reproduction, female animals will spend resources and energy maintaining their overall body health, including muscles, neurons, intestines and other nonreproductive organs. Sensing male pheromones triggers downstream signaling from the nervous system to the rest of the body, causing the female animals to shift their energy and resources to increasing reproductive health instead. The result? Better eggs but faster decay of the body.

The pheromone tricks the female into sending help to her eggs and shortchanging the rest of her body. It’s not all or nothing, but it’s shifting the balance.

The researchers think this finding potentially could lead to pharmacological interventions that combat infertility issues in humans by improving egg cell quality and delaying the onset of reproductive aging.

Reproductive aging affects everyone. One of the first signs of biological aging is the decreased quality of reproductive cells, which causes reduced fertility, increased incidence of fetal defects including miscarriages, and eventually loss of fertility. By all criteria scientists could think of, male pheromones made the eggs better.

Of course, there are unfortunate trade-offs. When female roundworms neglected the rest of their body to focus their energy on reproductive health, they were more likely to experience early death.

Erin Z. Aprison, Svetlana Dzitoyeva, David Angeles-Albores, Ilya Ruvinsky. A male pheromone that improves the quality of the oogenic germline. Proceedings of the National Academy of Sciences, 2022; 119 (21) DOI: 10.1073/pnas.2015576119

https://news.northwestern.edu/stories/2022/05/male-pheromones-impro....

Comment by Dr. Krishna Kumari Challa on May 23, 2022 at 6:46am

Scientists devise method to prevent deadly hospital infections without antibiotics

 A hospital or medical clinic might be the last place you’d expect to pick up a nasty infection, but that is what happens usually resulting in hundreds of deaths from infection-related complications and billions in direct medical costs.

The biggest culprits, experts say — accounting for two-thirds of these infections — are medical devices like catheters, stents, heart valves and pacemakers, whose surfaces often become covered with harmful bacterial films. But a novel surface treatment developed by a  team of scientists could help improve the safety of these devices and ease the economic burden on the health care system.

The new approach, tested in both laboratory and clinical settings, involves depositing a thin layer of what is known as zwitterionic material on the surface of a device and permanently binding that layer to the underlying substrate using ultraviolet light irradiation. The resulting barrier prevents bacteria and other potentially harmful organic materials from adhering to the surface and causing infection.

In the laboratory, researchers applied the surface treatment to several commonly used medical device materials, then tested the modified materials’ resistance to various types of bacteria, fungi and proteins. They found that the treatment reduced biofilm growth by more than 80% — and in some cases up 93%, depending on the microbial strain.

The modified surfaces exhibited robust resistance against microorganisms and proteins. The surfaces greatly reduced or even prevented biofilm formation.

Brian McVerry, Alexandra Polasko, Ethan Rao, Reihaneh Haghniaz, Dayong Chen, Na He, Pia Ramos, Joel Hayashi, Paige Curson, Chueh‐Yu Wu, Praveen Bandaru, Mackenzie Anderson, Brandon Bui, Aref Sayegh, Shaily Mahendra, Dino Di Carlo, Evgeniy Kreydin, Ali Khademhosseini, Amir Sheikhi, Richard B. Kaner. A Readily Scalable, Clinically Demonstrated, Antibiofouling Zwitterionic Surface Treatment for Implantable Medical Devices. Advanced Materials, 2022; 2200254 DOI: 10.1002/adma.202200254

https://newsroom.ucla.edu/releases/surface-treatment-for-medical-de...

Comment by Dr. Krishna Kumari Challa on May 22, 2022 at 11:27am

Exoskeleton device helps stroke victims regain hand function

Comment by Dr. Krishna Kumari Challa on May 21, 2022 at 1:23pm

However, the pressure of the solar wind seems to play little role in the brightness of said auroras. This suggests that space weather events, such as coronal mass ejections, where masses of charged particles are ejected from the Sun and are associated with higher solar wind pressure, may trigger Martian auroras.

Inside the crustal magnetic field regions, the orientation of the magnetic field and the solar wind seems to play a significant role in the formation of auroras on Mars. At certain orientations, the solar wind seems to be favorable to the magnetic reconnection events or particle acceleration required to produce the ultraviolet glow.

These results, the researchers said, reveal new information on how interactions with the solar wind can generate auroras on a planet stripped of its global magnetic field. This information can be used to help better understand the formation of discrete auroras on very different worlds.

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021JA030238

Part 2

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Comment by Dr. Krishna Kumari Challa on May 21, 2022 at 1:23pm

Mars Has Auroras Without a Global Magnetic Field

Earth's auroras are a glorious wonder, but our planet isn't the only place in the Solar System where these phenomena can be found. An atmospheric glow, albeit sometimes in invisible wavelengths, has been spotted at every planet except Mercury, and even some moons of Jupiter... and even a comet. But Mars is where it gets interesting. The red planet is famous for its lost global magnetic field, an ingredient that plays a crucial role in the formation of aurora elsewhere.

But that doesn't mean Mars is totally magnetism-free. Regions of localized magnetic fields sprout from some regions of the crust, particularly in the southern hemisphere. New analysis has confirmed that these small, local magnetic fields interact with the solar wind in interesting ways to produce Mars's discrete (or structured) ultraviolet auroras.

The new main finding is that inside the strong crustal field region, the aurora occurrence rate depends mostly on the orientation of the solar wind magnetic field, while outside the strong crustal field region, the occurrence rate depends mostly on the solar wind dynamic pressure.

But Mars's global magnetic field decayed fairly early on in the planet's history, leaving behind only patches of magnetism preserved in magnetized minerals in the crust. Ultraviolet images of Mars at night have revealed that auroras tend to form near these crustal magnetic fields, which makes sense if magnetic field lines are required for particle acceleration.  Outside the crustal magnetic field regions, the dynamic pressure of the solar wind plays a significant role in the detection frequency of auroras.

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