Comment

Comment by Dr. Krishna Kumari Challa on December 14, 2021 at 11:47am

A longer-lasting COVID vaccine

Researchers have identified rare, naturally occurring T cells that are capable of targeting a protein found in SARS-CoV-2 and a range of other coronaviruses.

The findings suggest that a component of this protein, called viral polymerase, could potentially be added to COVID-19 vaccines to create a longer-lasting immune response and increase protection against new variants of the virus.

Most COVID-19 vaccines use part of the spike protein found on the surface of the virus to prompt the immune system to produce antibodies. However, newer variants — such as delta and omicron — carry mutations to the spike protein, which can make them less recognizable to the immune cells and antibodies stimulated by vaccination. Researchers say that a new generation of vaccines will likely be needed to create a more robust and wide-ranging immune response capable of beating back current variants and those that may arise in the future.

One way to accomplish this is by adding a fragment of a different viral protein to vaccines — one that is less prone to mutations than the spike protein and that will activate the immune system’s T cells. T cells are equipped with molecular receptors on their surfaces that recognize foreign protein fragments called antigens. When a T cell encounters an antigen its receptor recognizes, it self-replicates and produces additional immune cells, some of which target and kill infected cells immediately and others which remain in the body for decades to fight that same infection should it ever return.

The researchers focused on the viral polymerase protein, which is found not only in SARS-CoV-2 but in other coronaviruses, including those that cause SARS, MERS and the common cold. Viral polymerases serve as engines that coronaviruses use to make copies of themselves, enabling infection to spread. Unlike the spike protein, viral polymerases are unlikely to change or mutate, even as viruses evolve.

To determine whether or not the human immune system has T cell receptors capable of recognizing viral polymerase, the researchers exposed blood samples from healthy human donors (collected prior to the COVID-19 pandemic) to the viral polymerase antigen. They found that certain T cell receptors did, in fact, recognize the polymerase. They then used a method they developed called CLInt-Seq to genetically sequence these receptors. Next, the researchers engineered T cells to carry these polymerase-targeting receptors, which enabled them to study the receptors’ ability to recognize and kill SARS-CoV-2 and other coronaviruses.

The study was published online in the journal Cell Reports.

https://researchnews.cc/news/10477/A-longer-lasting-COVID-vaccine--...

---

**

Comment by Dr. Krishna Kumari Challa on December 14, 2021 at 10:48am

Testing Mars Sample Return

Teams across multiple NASA centers and the European Space Agency are working together to prepare a set of missions that would return the samples being collected by the Mars Perseverance rover safely back to Earth. This video features some of that prototype testing underway for the proposed Sample Retrieval Lander, Mars Ascent Vehicle launch systems, and the Earth Entry System. Credit: NASA/JPL-Caltech

Comment by Dr. Krishna Kumari Challa on December 14, 2021 at 10:17am

New resistance-busting antibiotic combination could extend the use of 'last-resort' antibiotics

Scientists have discovered a new potential treatment that has the ability to reverse antibiotic resistance in bacteria that cause conditions such as sepsis, pneumonia, and urinary tract infections.

Carbapenems, such as meropenem, are a group of vital often 'last-resort' antibiotics used to treat serious, multi-drug resistant infections when other antibiotics, such as penicillin, have failed. But some bacteria have found a way to survive treatment with carbapenems, by producing enzymes called metallo-beta-lactamases (MBLs) that break down the carbapenem antibiotics, stopping them from working.

Highly collaborative research, conducted by scientists from the Ineos Oxford Institute (IOI) for Antimicrobial Research at the University of Oxford and several institutions across Europe, found that the new class of enzyme blockers, called indole carboxylates, can stop MBL resistance enzymes working leaving the antibiotic free to attack and kill bacteria such as E. coli in the lab and in infections in mice.

The researchers first screened hundreds of thousands of chemicals to see which would attach tightly to MBLs to stop them working, and which didn't react with any human proteins, leading to the discovery of the indole carboxylates as promising new candidates. Using a process called crystallography to zoom in to take a closer look at how they work, the researchers found these potential drugs attach to MBLs in a completely different way to any other drugs—they imitate the interaction of the antibiotic with the MBLs. This clever Trojan Horse trick allows these potential drugs to be highly effective against a very wide range of MBL-producing superbugs.

Jürgen Brem, Imitation of β-lactam binding enables -spectrum metallo-β-lactamase inhibitors, Nature Chemistry (2021). DOI: 10.1038/s41557-021-00831-x. www.nature.com/articles/s41557-021-00831-x

https://phys.org/news/2021-12-resistance-busting-antibiotic-combina...

Comment by Dr. Krishna Kumari Challa on December 14, 2021 at 10:12am

Researchers discover how cells from tumors remain dormant for years before metastasis occurs

Researchers have solved a major mystery in cancer research: How cancer cells remain dormant for years after they leave a tumor and travel to other parts of the body, before awakening to create metastatic cancer.

According to findings reported in Nature Cancer in December, the cells remain quiet by secreting a type of collagen, called type III collagen, in the environment around themselves, and only turn malignant once the level of collagen tapers off. The researchers found that by enriching the environment around the cells with this collagen, they could force the cells to remain in a dormant state and prevent tumour recurrence.

Most cancer deaths are due to metastases, which can occur several years after a tumor is removed. Previous research has studied how dispersed tumor cells come out of dormancy; this new work showed how the cells remain dormant.

In patient samples, the researchers showed that an abundance of the collagen could be used as a potential measurement to predict tumor recurrence and metastasis. In the mouse models, when scientists increased the amount of type III collagen around cancer cells that had left a tumor, cancer progression was interrupted and the disseminated cells were forced into a dormant state. Similar to wound treatment, in which collagen scaffolds have been proposed as a therapeutic alternative for complex skin wounds, this study suggest that by using strategies that aim to enrich the tumor microenvironment in type III collagen, metastasis may be prevented by activating tumor cell dormancy.

Jose Bravo-Cordero, A tumor-derived type III collagen-rich ECM niche regulates tumor cell dormancy, Nature Cancer (2021). DOI: 10.1038/s43018-021-00291-9. www.nature.com/articles/s43018-021-00291-9

https://medicalxpress.com/news/2021-12-cells-tumors-dormant-years-m...

Comment by Dr. Krishna Kumari Challa on December 14, 2021 at 8:47am

Synthetic food dyes and cancer

Although none of the FDA-approved synthetic food colors are classified as carcinogens, currently available research points to potential health risks and   researchers  find this concerning.

For instance, the bacteria in your gut can break down synthetic dyes into molecules that are known to cause cancer. More research is needed on how the microbiome interacts with synthetic food coloring and potential cancer risk.

Studies have shown that artificial food dyes can bind to the DNA and proteins inside cells. There is also some evidence that synthetic dyes can stimulate the body's inflammatory machinery. Both of these mechanisms may pose a problem for colon and rectal health.

Synthetic food dyes have been found to damage DNA in rodents. This is supported by unpublished data from my research team showing that Allura Red, or Red 40, and Tartrazine, or Yellow 5, can cause DNA damage in colon cancer cells with increased dosages and length of exposure in vitro in a controlled lab environment.

Our results will need to be replicated in animal and human models before we can say that these dyes directly caused DNA damage, however.

Finally, artificial food coloring may be of particular concern for children. It's known that children are more vulnerable to environmental toxins because their bodies are still developing. I and others believe that this concern may extend to synthetic food dyes, especially considering their prevalence in children's food.

A 2016 study found that over 40 percent of food products marketed toward children in one major supermarket in North Carolina contained artificial food coloring. More research needs to be done to examine how repeated exposure to artificial food dyes may affect children.

A few treats during the holidays won't cause colorectal cancer. But a long-term diet of processed foods might. While more research is needed on the link between synthetic food dyes and cancer, there are evidence-based steps you can take now to reduce your risk of colorectal cancer.

One way is to get screened for colon cancer. Another is to increase your physical activity. Finally, you can eat a healthy diet with more whole grains and produce and less alcohol and red and processed meat. Though this means eating fewer of the colorful, ultra-processed foods that may be plentiful during the holidays, your gut will thank you in the long run.

https://theconversation.com/colorful-sweets-may-look-tasty-but-some...

Comment by Dr. Krishna Kumari Challa on December 14, 2021 at 8:44am

The food industry uses synthetic dyes because they make food look better. The first food dyes were created from coal tar in the late 1800s. Today, they are often synthesized from a chemical derived from petroleum called naphthalene to make a final product called an azo dye.

Food manufacturers prefer synthetic dyes over natural dyes like beet extract because they are cheaper, brighter, and last longer. While manufacturers have developed hundreds of synthetic food dyes over the past century, the majority of them are toxic. Only nine are approved for use in food under U.S. Food and Drug Administration policy, and even fewer pass European Union regulations.

What drives colorectal cancer?

DNA damage is the primary driver of colorectal cancer. When DNA damage occurs on cancer driver genes, it can result in a mutation that tells the cell to divide uncontrollably and turn cancerous.

Another driver of colorectal cancer is inflammation. Inflammation occurs when the immune system sends out inflammatory cells to begin healing an injury or capture disease-causing pathogens.

When this inflammation persists over time, it can harm otherwise healthy cells by releasing molecules called free radicals that can damage DNA.

Another type of molecule called cytokines can prolong inflammation and drive increased cell division and cancer development in the gut when there isn't an injury to heal.

Long-term poor dietary habits can lead to a simmering low-grade inflammation that doesn't produce noticeable symptoms, even while inflammatory molecules continue to damage otherwise healthy cells.

Part 2

Comment by Dr. Krishna Kumari Challa on December 14, 2021 at 8:43am

Synthetic Food Dyes and health risk

Early-onset colorectal cancer incidence among the young, defined as those under age 50, has been rising globally since the early 1990s. Rates for colon and rectal cancers are expected to increase by 90 percent and 124 percent, respectively, by 2030.

One suspected reason behind this trend is increased global consumption of a Westernized diet that consists heavily of red and processed meats, added sugar, and refined grains. Modern day diet is made up of ultra-processed food such as industrial baked sweets, soft drinks, and processed meat. It is associated with an increased risk of colorectal cancer.

One aspect of ultra-processed foods I'm concerned about is how colorful they are. This characteristic is on full display in many delicious foods and treats present during the year-end holidays.

However, many of the colours that make up candy canes, sugar cookies, and even cranberry sauce and roast ham, are synthetic. And there's some evidence that these artificial food dyes may trigger cancer-causing processes in the body.

Part 1

Comment by Dr. Krishna Kumari Challa on December 14, 2021 at 8:08am

Scientists Smash Temperature Record on Keeping 'Freezing Cold' Water in Liquid Form

Scientists have just proven that the freezing temperature of water can be even lower than what we thought was possible.

Taking tiny droplets of water, up to just 150 nanometers in size, a team of engineers at the University of Houston has pushed the critical temperature threshold to -44 degrees Celsius (-47.2 degrees Fahrenheit) – and, more saliently, accurately measured it.

common H₂O is actually pretty weird; it doesn't behave like any other liquid. Even the way it freezes is weird: where other liquids increase in density as they cool, water actually becomes less dense as it freezes.

Water's behavior has been fairly well characterized and studied. We know, for example, that it tends to nucleate, or form ice crystals, at a variety of temperatures, sometimes resisting the process as far as -38 degrees Celsius. Any colder, and even the most stubborn water molecules will stick together as ice.

pushed that temperature downwards by placing nanodroplets of water on a soft surface, like a gel or a lipid. Then, they probed the droplets using electrical resistance metrology and Fourier transform infrared spectroscopy to take their temperature as they froze.

The soft interface between the surface and the tiny droplet seemed to play a role in the suppression of ice nucleation, possibly because of the way the interface generates a large pressure on the droplet.

This is because the freezing temperature of water drops as ambient pressure rises. The most pronounced effect was seen in a droplet of water just 2 nanometers across.

If a water droplet is in contact with a soft interface, freezing temperature could be significantly lower than hard surfaces. And a few-nanometer water droplet could avoid freezing down to -44 degrees Celsius if it is in contact with a soft interface.

The way tiny water droplets freeze is vitally important to cryopreservation, since the freezing of tiny droplets within cells can cause those cells to rupture and die. Learning how to slow or halt that process could help scientists find ways to mitigate that effect. It could also help us better understand how nucleation happens in the atmosphere, where microscopic droplets of water freeze. And it could also help us to better design technology that suffers from ice exposure, such as aircraft and wind turbines.

https://www.nature.com/articles/s41467-021-27346-w

https://www.sciencealert.com/scientists-break-a-temperature-record-...

Comment by Dr. Krishna Kumari Challa on December 11, 2021 at 9:50am

Science with Webb: the nearby cosmos

Comment by Dr. Krishna Kumari Challa on December 11, 2021 at 9:24am

Inching closer towards "living biotherapeutics"

The human gut is home to thousands of species of bacteria, and some of those bacteria have the potential to treat a variety of gastrointestinal diseases. Some species may help to combat colon cancer, while others could help treat or prevent infections such as C. difficile.

One of the obstacles to developing these "living biotherapeutics" is that many of the species that could be beneficial are harmed by oxygen, making it difficult to manufacture, store, and deliver them. Chemical engineers have now shown that they can protect those bacteria with a coating that helps them to survive the manufacturing process.

In a study appearing today in the Journal of the American Chemical Society, the researchers showed they could use the coating on a strain of E. coli as well as another species that may aid in digestion of plant starches. The coating could be applied to many other species as well, they say. They think this coating could be used to protect pretty much any microbe of interest.

Most of the microbes that live in the human gut are anaerobic, and they have varying degrees of sensitivity to oxygen. Some can tolerate a little bit of oxygen, while for others, oxygen is deadly.

This makes it difficult to test their potential as treatments for human disease, because bacteria need to be freeze-dried and formulated as capsules in order to be used therapeutically. In this study, researchers decided to try protecting anaerobic bacteria by coating them with a material made from metal ions and organic compounds called polyphenols.

When polyphenols and metal ions are put into a solution, they form a two-dimensional, grid-like sheet. For this study, the researchers used iron, which is safe for human consumption, and three polyphenols that are all classified as GRAS (generally regarded as safe) : gallic acid, tannic acid, and epigallocatechin (EGCG), all of which are found in tea and other plant products.

If bacteria are also added to the solution, the material self-assembles into a coating on individual bacterial cells. This coating protects bacteria during the freeze-drying and manufacturing process. The researchers showed that the coated cells were healthy and able to perform normal cellular activities, although their growth was temporarily inhibited.

When exposed to an acidic environment, such as that of the stomach, the coating breaks down and releases the bacteria. Coating the bacteria with a protective layer could eliminate the need for cold storage and make distribution easier. This would make a lot of therapeutics more widely available.

Gang Fan et al, Protection of Anaerobic Microbes from Processing Stressors Using Metal–Phenolic Networks, Journal of the American Chemical Society (2021). DOI: 10.1021/jacs.1c09018

https://phys.org/news/2021-12-biotherapeutics.html?utm_source=nwlet...

• ‹ Previous
• 1
• …
• 310
• 311
• 312
• 313
• 314
• …
• 849
• Next ›
• Page