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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...

Comment by Dr. Krishna Kumari Challa on April 29, 2022 at 11:24am

Scientists call for cap on production to end plastic pollution

Now, after the United Nations' historic decision to adopt a global treaty to end plastic pollution earlier this year, governmental negotiations on the agreement are set to begin on May 30th. These will foster intense debates on what kind of measures will be needed to end the pollution of the air, soils, rivers and oceans with plastic debris and microplastics.

In a letter to the journal Science, an international group of scientists and experts now argue for tackling the issue right at the source, by regulating, capping, and in the long term phasing out the production of new plastics. because, they think, recycling is not enough.

Even if we recycled better and tried to manage the waste as much as we can, we would still release more than 17 million tons of plastic per year into nature. If production just keeps growing and growing, we will be faced with a truly Sisyphean task.

 Melanie Bergmann et al, A global plastic treaty must cap production, Science (2022). DOI: 10.1126/science.abq0082

Winnie W. Y. Lau et al, Evaluating scenarios toward zero plastic pollution, Science (2020). DOI: 10.1126/science.aba9475

Nils Simon et al, A binding global agreement to address the life cycle of plastics, Science (2021). DOI: 10.1126/science.abi9010

https://phys.org/news/2022-04-scientists-cap-production-plastic-pol...

Comment by Dr. Krishna Kumari Challa on April 29, 2022 at 10:04am

Researchers discover new function performed by nearly half of brain cells

Researchers  have discovered a previously unknown function performed by a type of cell that comprises nearly half of all cells in the brain.

The scientists say this discovery in mice of a new function by cells known as astrocytes opens a whole new direction for neuroscience research that might one day lead to treatments for many disorders ranging from epilepsy to Alzheimer's to traumatic brain injury.

It comes down to how astrocytes interact with neurons, which are fundamental cells of the brain and nervous system that receive input from the outside world. Through a complex set of electrical and chemical signaling, neurons transmit information between different areas of the brain and between the brain and the rest of the nervous system.

Until now, scientists thought astrocytes were important, but lesser cast members in this activity. Astrocytes guide the growth of axons, the long, slender projection of a neuron that conducts electrical impulses. They also control neurotransmitters, chemicals that enable the transfer of electrical signals throughout the brain and nervous system. In addition, astrocytes build the blood-brain barrier and react to injury.

But they did not seem to be electrically active like the all-important neurons—until now. 

The electrical activity of astrocytes changes how neurons function.

Neuroscientists now have discovered a new way that two of the most important cells in the brain talk to each other. Because there is so much unknown about how the brain works, discovering new fundamental processes that control brain function is key to developing novel treatments for neurological diseases.

Neuron-to-neuron communication occurs through the release of packets of chemicals called neurotransmitters. Scientists knew that astrocytes control neurotransmitters, helping to make sure that neurons stay healthy and active. But the new study reveals that neurons also release potassium ions, which change the electrical activity of the astrocyte and how it controls the neurotransmitters.

So the neuron is controlling what the astrocyte is doing, and they are communicating back and forth. Neurons and astrocytes talk with each other in a way that has not been known about before.

Moritz Armbruster, Neuronal activity drives pathway-specific depolarization of peripheral astrocyte processes, Nature Neuroscience (2022). DOI: 10.1038/s41593-022-01049-x. www.nature.com/articles/s41593-022-01049-x

https://medicalxpress.com/news/2022-04-function-brain-cells.html?ut...

Comment by Dr. Krishna Kumari Challa on April 29, 2022 at 7:39am

All of the bases in DNA and RNA have now been found in meteorites

The discovery adds to evidence that suggests life’s precursors came from space

More of the ingredients for life have been found in meteorites.

Space rocks that fell to Earth within the last century contain the five bases that store information in DNA and RNA, scientists report April 26 in Nature Communications.

These “nucleobases” — adenine, guanine, cytosine, thymine and uracil — combine with sugars and phosphates to make up the genetic code of all life on Earth. Whether these basic ingredients for life first came from space or instead formed in a warm soup of earthly chemistry is still not known. But the discovery adds to evidence that suggests life’s precursors originally came from space, the researchers say.

Y. Oba et al. Identifying the wide diversity of extraterrestrial purine and pyrim.... Nature Communications. April 26, 2022. doi: 10.1038/s41467-022-29612-x.

Comment by Dr. Krishna Kumari Challa on April 29, 2022 at 7:23am

Antibiotics diminish babies’ immune response to key vaccines

The drugs disrupt gut bacteria, which appear to play a part in the body’s response to vaccines

Taking antibiotics in the first two years of life can prevent babies from developing a robust immune response to certain vaccines. The new finding provides another cautionary tale against overusing antibiotics, researchers say.

Babies get immunized in their first six months, and receive booster doses in their second year, to protect against certain infectious diseases. Antibiotic use during that time was associated with subpar immune responses to four vaccines babies receive to ward off whooping cough, polio and other diseases, researchers report online April 27 in Pediatrics.

And the more rounds of antibiotics a child received, the more antibody levels to the vaccines dropped below what’s considered protective. Levels induced by the primary series of shots for the polio, diphtheria-tetanus-pertussis, Haemophilus influenzae type b and pneumococcal vaccines fell 5 to 11 percent with each antibiotic course. In the children’s second year, antibody levels generated by booster shots of these vaccines dropped 12 to 21 percent per course.

If anyone needed yet another reason why overprescription of antibiotics is not a good thing, this research results offers that reason.

Taking antibiotics disrupts the population of bacteria that live in the gut. That’s well known, but researchers are still learning about how that disruption can affect a person’s health. The new study adds to evidence that diminishing the amount and diversity of gut bacteria impacts vaccination. In studies in mice, antibiotics hampered the immune system’s response to vaccines. And a small study in humans found that antibiotics dampened adults’ response to the flu vaccine in those whose prior immune memory for influenza had waned. (1)

The study in Pediatrics is the first to report an association between antibiotic use and compromised vaccine responses in children. 

The type and length of antibiotic treatment also made a difference. Broad spectrum drugs were associated with antibody levels below what is protective, while a more targeted antibiotic was not. Furthermore, a 10-day course, but not a five-day course, reduced vaccine-induced antibody levels.

T.J. Chapman et al. Antibiotic use and vaccine antibody levels. Pediatrics. Published online April 27, 2022. doi: 10.1542/peds.2021-052061

T. Hagan et al. Antibiotics-driven gut microbiome perturbation alters immunity to v.... Cell. Vol. 178, September 2019, p. 1313. doi: 10.1016/j.cell.2019.08.010

Comment by Dr. Krishna Kumari Challa on April 28, 2022 at 6:41am

How the James Webb Space Telescope Will Unfold the Universe

Microrobot collectives display versatile movement patterns

Comment by Dr. Krishna Kumari Challa on April 28, 2022 at 6:38am

New evidence of how exercise can counter diabetes damage

 One way exercise can counter the damage of diabetes is by enabling activation of a natural system we have to grow new blood vessels when existing ones are ravaged by this disease, scientists report.

Angiogenesis is the ability to form new blood vessels, and diabetes not only damages existing blood vessels, it hinders this innate ability to grow new ones in the face of disease and injury, say experts.

Endothelial cells line our blood vessels and are essential to that new blood vessel growth.

Now the MCG scientists have the first evidence that in the face of diabetes, even one 45-minute session of moderate intensity exercise enables more exosomes, submicroscopic packages filled with biologically active cargo, to deliver directly to those cells more of the protein, ATP7A, which can set angiogenesis in motion, they report in The FASEB Journal.

Kareem Abdelsaid, Varadarajan Sudhahar, Ryan A. Harris, Archita Das, Seock‐Won Youn, Yutao Liu, Maggie McMenamin, Yali Hou, David Fulton, Mark W. Hamrick, Yaoliang Tang, Tohru Fukai, Masuko Ushio‐Fukai. Exercise improves angiogenic function of circulating exosomes in type 2 diabetes: Role of exosomal SOD3. The FASEB Journal, 2022; 36 (3) DOI: 10.1096/fj.202101323R

https://researchnews.cc/news/12860/New-evidence-of-how-exercise-can...

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