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Comment by Dr. Krishna Kumari Challa on May 4, 2022 at 1:24pm

Humanity will need to survive about 400,000 years if we want any chance of hearing from an alien civilization

If there are so many galaxies, stars, and planets, where are all the aliens, and why haven't we heard from them? Those are the simple questions at the heart of the Fermi Paradox. In a new paper, a pair of researchers ask the next obvious question: How long will we have to survive to hear from another alien civilization?

Their answer? 400,000 years.

Four-hundred-thousand years is a long time for a species that's only been around for a couple hundred thousand years, and only discovered farming about 12,000 years ago. But 400,000 years is how long we'll need to keep this human experiment going if we want to hear from any alien civilizations. That's according to some new research into communicating extraterrestrial intelligent civilizations (CETIs.)

The paper is "The Number of Possible CETIs within Our Galaxy and the Communication Probability among These CETIs." The authors are Wenjie Song and He Gao, both from the Department of Astronomy at Beijing Normal University. The paper is published in The Astrophysical Journal.

Wenjie Song et al, The Number of Possible CETIs within Our Galaxy and the Communication Probability among These CETIs, The Astrophysical Journal (2022). DOI: 10.3847/1538-4357/ac561d

https://phys.org/news/2022-05-humanity-survive-years-chance-alien.h...

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Comment by Dr. Krishna Kumari Challa on May 4, 2022 at 1:19pm

Recurrent UTIs linked to gut microbiome, chronic inflammation

One of the greatest frustrations regarding urinary tract infections (UTIs) is that they so often recur. UTIs are caused by bacteria in the urinary tract and characterized by frequent and painful urination. A round of antibiotics usually clears up the symptoms, but the relief is often temporary: A quarter of women go on to develop a second UTI within six months. Some unfortunate individuals get UTIs over and over, and require antibiotics every few months.

A new study suggests that women who get recurrent UTIs may be caught in a vicious cycle in which antibiotics given to eradicate one infection predispose them to develop another. The study, by researchers at Washington University School of Medicine in St. Louis and the Broad Institute of MIT and Harvard, showed that a round of antibiotics eliminates disease-causing bacteria from the bladder but not from the intestines. Surviving bacteria in the gut can multiply and spread to the bladder again, causing another UTI.

At the same time, repeated cycles of antibiotics wreak havoc on the community of helpful bacteria that normally live in the intestines, the so-called gut microbiome. Similar to other disorders in which gut microbes and the immune system are linked, women with recurrent UTIs in the study had less diverse microbiomes that were deficient in an important group of bacteria that helps regulate inflammation, and a distinct immunological signature in their blood indicative of inflammation.

The study is published May 2 in Nature Microbiology.

The difference between the women who got repeated UTIs and those who didn't, surprisingly, didn't come down to the kind of E. coli in their intestines or even the presence of E. coli in their bladders. Both groups carried E. coli strains in their guts capable of causing UTIs, and such strains occasionally spread to their bladders.

The real difference was in the makeup of their gut microbiomes. Patients with repeat infections showed decreased diversity of healthy gut microbial species, which could provide more opportunities for disease-causing species to gain a foothold and multiply. Notably, the microbiomes of women with recurrent UTIs were particularly scarce in bacteria that produce butyrate, a short-chain fatty acid with anti-inflammatory effects.

Women in the control group were able to clear the bacteria from their bladders before they caused disease, and women with recurrent UTI were not, because of a distinct immune response to bacterial invasion of the bladder potentially mediated by the gut microbiome.

The findings highlight the importance of finding alternatives to antibiotics for treating UTIs.

this study clearly demonstrates that antibiotics do not prevent future infections or clear UTI-causing strains from the gut, and they may even make recurrence more likely by keeping the microbiome in a disrupted state.

Scott Hultgren, Longitudinal multi-omics analyses link gut microbiome dysbiosis with recurrent urinary tract infections in women, Nature Microbiology (2022). DOI: 10.1038/s41564-022-01107-x. www.nature.com/articles/s41564-022-01107-x

https://medicalxpress.com/news/2022-05-recurrent-utis-linked-gut-mi...

Comment by Dr. Krishna Kumari Challa on May 4, 2022 at 1:10pm

Why is the 100-year-old BCG vaccine so broadly protective in newborns?

The century-old Bacille Calmette-Guérin (BCG) vaccine against tuberculosis is one of the world's oldest and most widely used vaccines, used to immunize 100 million newborns every year. Given in countries with endemic TB, it has surprisingly been found to protect newborns and young infants against multiple bacterial and viral infections unrelated to TB. There's even some evidence that it can reduce severity of COVID-19.

What's special about BCG vaccine? How does it protect infants so broadly? It turns out little is known. To understand its mechanism of action, researchers at the Precision Vaccines Program at Boston Children's Hospital partnered with the Expanded Program on Immunization Consortium (EPIC), an international team studying early life immunization, to collect and comprehensively profile blood samples from newborns immunized with BCG, using a powerful "big data" approach.

Their study, published online May 3 in Cell Reports, found that the BCG vaccine induces specific changes in metabolites and lipids that correlate with innate immune system responses. The findings provide clues toward making other vaccines more effective in vulnerable populations with distinct immune systems, such as newborns.

BCG is an 'old school' vaccine—it's made from a live, weakened germ—but live vaccines like BCG seem to activate the immune system in a very different way in early life, providing broad protection against a range of bacterial and viral infections. There's much work ahead to better understand that and use that information to build better vaccines for infants.

Joann Diray-Arce, Bacille Calmette-Guérin vaccine reprograms human neonatal lipid metabolism in vivo and in vitro, Cell Reports (2022). DOI: 10.1016/j.celrep.2022.110772. www.cell.com/cell-reports/full … 2211-1247(22)00536-8

https://medicalxpress.com/news/2022-05-year-old-bcg-vaccine-broadly...

Comment by Dr. Krishna Kumari Challa on May 3, 2022 at 10:47am

Change Is Happening to Earth's Water Cycle

Climate change is throwing Earth's water cycle severely out of whack. According to new satellite data, freshwaters are growing fresher and salt waters are growing saltier at an increasingly rapid rate all around the world. If this pattern continues, it will turbocharge rainstorms.

The findings indicate a severe acceleration of the global water cycle – a sign that isn't as clearly observed in direct salinity measurements from ocean buoys, which typically measure a little below the surface of the ocean. However, it's commonly predicted in climate models. 

As global temperatures increase, climate scientists expect there will be greater evaporation on the ocean surface, which will make the top layer of the sea saltier and add moisture to the atmosphere.

This, in turn, will increase rainfall in other parts of the world, diluting some bodies of water to make them even less salty.

The pattern can basically be described as "wet-gets-wetter-dry-gets-drier", and it's a real cause for concern. If the water cycle accelerates with global warming, it could have profound impacts on modern society, driving drought and water shortages, as well as greater storms and flooding. 

It might even have started speeding up snow melt, as rainfall has been increasing in polar regions.

This higher amount of water circulating in the atmosphere could also explain the increase in rainfall that is being detected in some polar areas, where the fact that it is raining instead of snowing is speeding up the melting.

https://www.nature.com/articles/s41598-022-10265-1

Comment by Dr. Krishna Kumari Challa on May 3, 2022 at 8:17am

A gravity telescope that could image exoplanets

In the time since the first exoplanet was discovered in 1992, astronomers have detected more than 5,000 planets orbiting other stars. But when astronomers detect a new exoplanet, we don't learn a lot about it: We know that it exists and a few features about it, but the rest is a mystery.

To sidestep the physical limitations of telescopes, Stanford University astrophysicists have been working on a new conceptual imaging technique that would be 1,000 times more precise than the strongest imaging technology currently in use. By taking advantage of gravity's warping effect on space-time, called lensing, scientists could potentially manipulate this phenomenon to create imaging far more advanced than any present today.

In a paper published on May 2 in The Astrophysical Journal, the researchers describe a way to manipulate solar gravitational lensing to view planets outside our solar system. By positioning a telescope, the sun, and exoplanet in a line with the sun in the middle, scientists could use the gravitational field of the sun to magnify light from the exoplanet as it passes by. As opposed to a magnifying glass which has a curved surface that bends light, a gravitational lens has a curved space-time that enables imaging far away objects.

In order to capture an exoplanet image through the solar gravitational lens, a telescope would have to be placed at least 14 times farther away from the sun than Pluto, past the edge of our solar system, and further than humans have ever sent a spacecraft. But, the distance is a tiny fraction of the light-years between the sun and an exoplanet.

By unbending the light bent by the sun, an image can be created far beyond that of an ordinary telescope. So, the scientific potential is an untapped mystery because it's opening this new observing capability that doesn't yet exist.

The solar gravitational lens opens up an entirely new window for observation. This will allow investigation of the detailed dynamics of the planet atmospheres, as well as the distributions of clouds and surface features, which we have no way to investigate now.

Alexander Madurowicz et al, Integral Field Spectroscopy with the Solar Gravitational Lens, The Astrophysical Journal (2022). DOI: 10.3847/1538-4357/ac5e9d

https://phys.org/news/2022-05-scientists-gravity-telescope-image-ex...

Comment by Dr. Krishna Kumari Challa on May 2, 2022 at 11:51am

Researchers identify 'super-calculating' network in the human brain

Are you impressed when Scientists manage to calculate the time and speed of a rocket's trajectory? A new study shows that your brain has a "nerd center" capable of even more complex calculations.

If, late on your way to work, you see the bus coming and run to catch it while carrying your cup of coffee, you have probably beaten rocket scientists. Nerve cells in your brain perform billions of complicated mathematical calculations to work out your speed, position and direction. For years, this ability of the brain to calculate such parameters has been a mystery.

After five years of research into the theory of the continuous attractor network, or CAN, a group of scientists have made a breakthrough.
They are the first to clearly establish that the human brain actually contains such 'nerd cells' or 'super-calculators' put forward by the CAN theory. They also found nerve cells that code for speed, position and direction all at once.

The CAN theory  had been widely popular among scientists for decades. In a nutshell, it proposes that when we move around, our mental map or representation of the place in which we find ourselves constantly updates itself according to our new position. The CAN theory hypothesizes that a hidden layer of nerve cells perform complex math and compile vast amounts of information about speed, position and direction, just as space scientists do when they are adjusting a rocket trajectory.

At all times, the brain is bombarded with sensory experiences (sight, feelings, hearing). It must make sense of this chaos to create an image coherent with memories of similar situations previously experienced in order to adjust one's actions. For example, we see that the bus is coming, we can feel that the coffee is hot; at which speed can we run to reach the bus without burning ourselves?

In recent years, the research community has proven that these brain areas is involved in many more tasks beyond mapping spatial position. The nerve cells there can also map sounds and rewards. Now,scientists wonder whether the cells they found are capable of performing other tasks, in addition to calculating speed and direction.

Davide Spalla et al, Angular and linear speed cells in the parahippocampal circuits, Nature Communications (2022). DOI: 10.1038/s41467-022-29583-z

https://researchnews.cc/news/12939/Researchers-identify--super-calc...

Comment by Dr. Krishna Kumari Challa on April 30, 2022 at 11:10am

The breakthrough science of mRNA medicine

The secret behind medicine that uses messenger RNA (or mRNA) is that it "teaches" our bodies how to fight diseases on our own, leading to groundbreaking treatments for COVID-19 and, potentially one day, cancer, the flu and other ailments that have haunted humanity for millennia. RNA researcher Melissa J. Moore -- Moderna's chief scientific officer and one of the many people responsible for the rapid creation and deployment of their COVID-19 vaccine -- takes us down to the molecular level, unraveling how mRNA helps our bodies' proteins maintain health, prevent disease and correct errors in our genetic code. "We have entered an entirely new era of medicine

https://www.ted.com/talks/melissa_j_moore_the_breakthrough_science_...

Comment by Dr. Krishna Kumari Challa on April 30, 2022 at 9:03am

At the molecular level, the team found that CAF-1 normally keeps specific genomic sites compacted and inaccessible to specific transcription factors, especially one called ELF1.

By looking at chromatin organization, we found a whole slew of genomic sites that are aberrantly open and attract ELF1 as a result of CAF-1 loss. This study further points to a key role of ELF1 in defining the fate of several blood cell lineages.

The UCR researchers used immature blood cells derived from mouse bone marrow and engineered for growth in tissue culture. They validated their findings in vivo using a mouse model.

Regulation of Chromatin Accessibility by the Histone Chaperone CAF-1 Sustains Lineage Fidelity., Nature Communications (2022). DOI: 10.1038/s41467-022-29730-6

https://phys.org/news/2022-04-blood-stem-cells-fate.html?utm_source...

Part 2

Comment by Dr. Krishna Kumari Challa on April 30, 2022 at 9:02am

Study identifies how blood stem cells maintain their fate

Understanding the molecular mechanisms that specify and maintain the identities of more than 200 cell types of the human body is arguably one of the most fundamental problems in molecular and cellular biology, with critical implications for the treatment of human diseases. Central to the cell fate decision process are stem cells residing within each tissue of the body.

When stem cells divide, they have the remarkable ability to choose to self-renew—that is, make a copy of themselves—or mature into defined lineages. How a specific lineage identity is maintained every time a stem cell divides can now be better understood thanks to the work of  biochemists. 

The study shows how a protein complex, called chromatin assembly factor-1, or CAF-1, controls genome organization to maintain lineage fidelity. The report appears today in Nature Communications. Each time a cell divides, it has to create a replica of its genome—not only its DNA sequence but also how the DNA is packaged with proteins into chromatin. Chromatin is organized into genomic sites that are either open and easily accessible or more densely packed and less accessible (or closed). Identities of different cells rely heavily on the genome sites that are more open because only genes located in those regions can potentially become expressed and turned into proteins.

To maintain cell identity during cell division, the locations of open and closed chromatin, or "chromatin organization," must be faithfully passed onto the new replica of the genome, a task largely entrusted to CAF-1.

To help CAF-1 secure correct chromatin organization during cell division, a host of transcription factors are attracted to open regions in a DNA sequence-specific manner to serve as bookmarks and recruit transcription machinery to correct lineage-specific genes, ensuring their expression.

The authors took as a study paradigm immature blood cells that can either self-renew or turn into neutrophils, which are non-dividing cells that present our body's first line of defense against pathogens. Intriguingly, they found CAF-1 to be essential not only for maintaining the self-renewal of these immature blood cells, but for preserving their lineage identity. Even a moderate reduction of CAF-1 levels caused the cells to forget their identity and adopt a mixed lineage stage.

Neutrophil stem cells missing CAF-1 become more plastic, co-expressing genes from different lineages, including those of red blood cells  and platelets.

Part 1

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Comment by Dr. Krishna Kumari Challa on April 30, 2022 at 8:09am

Osteoarthritis: Realigning bad knees may prompt the body to generate cartilage again

Osteoarthritis is a wear-and-tear disorder marked by bone thickening and cartilage degeneration, an excruciatingly painful disability and a major cause of impaired mobility as people age. But scientists have begun viewing this form of arthritis differently with a deeper understanding of the disorder's causes and an eye toward personalized medicine as a treatment option.

Although for decades medical experts have focused on problems such as the pain caused by bone thickening and the disappearance of cartilage, scientists conducting research in Homburg, Germany at the Institute of Experimental Orthopedics and Osteoarthritis Research, say bone malalignment may play a critical role in osteoarthritis. In a novel clinical study, medical scientists demonstrate how the alignment problem can contribute to osteoarthritis—and they also suggest that correcting it can protect cartilage and reverse its degeneration.

Researchers launched a two-pronged approach to the problem demonstrating in both animal research and in a human case study that relieving a troublesome misalignment of the joint can help alleviate pain and restore the shock-absorbing role of cartilage in the knee. They report that malalignment of a joint can cause excessive pressure to be placed on it in a manner similar to a condition known as varus malalignment, more commonly known as bow-leggedness. People with severe forms of that condition can suffer cartilage loss and impaired mobility.

By correcting the misaligned joint—unloading pressure on it—the team discovered they could restore function and reduce pain.

Tamás Oláh et al, Axial alignment is a critical regulator of knee osteoarthritis, Science Translational Medicine (2022). DOI: 10.1126/scitranslmed.abn0179

https://medicalxpress.com/news/2022-04-osteoarthritis-bad-knees-pro...

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