Comment

Comment by Dr. Krishna Kumari Challa on October 13, 2022 at 8:42am

Researchers have found a way to restore sight in adult mice

 Researchers have found a way to restore sight in adult mice with a form of congenital blindness, in spite of the rodents' relative maturity.

The mice were modeling a rare human disorder of the eye's retina, called leber congenital amaurosis (LCA), which often causes blindness or severe visual impairment at birth.

This inherited condition seems to be caused by a mutation in any one of dozens of genes associated with the retina and its light-sensing abilities.

Researchers have been working on treatments that could restore damaged or dysfunctional photoreceptors in this part of the eye for several decades. Some strategies include retinal implants, gene editing interventions, and drug treatments.

These emerging therapies all boost vision with varying levels of success, but synthetic compounds that target the retina look particularly promising for those with mutations that involve rod photoreceptors.

Rods are the photoreceptors at the back of the eye that sense dim light. These specialized neurons utilize a series of biochemical reactions to convert sensory light into electrical signals for the rest of the brain to 'read'.

As light-sensitive pigments in retinal rods absorb low levels of light, they convert the molecule 11-cis retinal into all-trans-retinal, which in turn generates an impulse that travels down the optic nerve to the brain.

Previous studies on children with LCA have shown that synthetic retinoid treatments can help compensate for some vision loss when injected straight into the eye. But how these treatments impact adults with the condition is not as well understood.

"Although some progress has been made, it still remains unclear the extent to which adult visual circuits can be restored to a fully functional state at the level of the visual cortex upon correction of the retinal defect. Traditionally, it's been thought that the brain's visual system is formed and strengthened during certain developmental windows in early life. If the eye isn't being exercised during these critical periods, then visual networks in the brain may never be wired properly for sight, leading to lifelong deficits in vision.

But a mammal's potential for vision may not be so rigidly wired; it could be far more plastic than assumed.

To explore this idea, researchers administered a synthetic retinoid for seven days to adult rodents born with retinal degeneration.

The treatment was ultimately successful at partially restoring the animals' light sensitivity and their typical light-orienting behaviors for 27 days.

Nine days after treatment, far more neurons in the visual cortex were being activated by the optic nerve.

This suggests the central visual pathway that carries information from the eye to the visual cortex can be significantly restored by retinoid treatment, even in adult mice.Immediately after the treatment, the signals coming from the opposite-side eye, which is the dominant pathway in the mouse, activated two times more neurons in the brain. What was even more mind-blowing was that the signals coming from the same-side eye pathway activated five-fold more neurons in the brain after the treatment and this impressive effect was long-lasting.

https://www.sciencedirect.com/science/article/pii/S096098222201449X...

Comment by Dr. Krishna Kumari Challa on October 13, 2022 at 8:27am

Algorithms predict sports teams’ moves with 80% accuracy.

Comment by Dr. Krishna Kumari Challa on October 12, 2022 at 9:18am

NASA spaceship deflected asteroid in test to save Earth

NASA on Tuesday said it had succeeded in deflecting an asteroid in a historic test of humanity's ability to stop an incoming cosmic object from devastating life on Earth.

The fridge-sized Double Asteroid Redirection Test (DART) impactor deliberately smashed into the moonlet asteroid Dimorphos on September 26, pushing it into a smaller, faster orbit around its big brother Didymos, said NASA.

 DART shortened the 11 hour 55 minute orbit to 11 hours and 23 minutes. Speeding up Dimorphos' orbital period by 32 minutes exceeded NASA's own expectation of 10 minutes.

DART's success as a proof-of-concept has made a reality of science fiction—notably in films such as "Armageddon" and "Don't Look Up."

Kinetic impact with a spaceship is just one way to defend the planet, albeit the only method possible with current technology.

Should an approaching object be detected early, a spaceship could be sent to fly alongside it for long enough to divert its path via using the ship's gravitational pull, creating a so-called gravity tractor.

Another option would be launching nuclear explosives to redirect or destroy an asteroid.

Source: NASA

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

How genetics influences our body weight beyond genes

Heredity plays a role in how strongly we are predisposed to put on excess weight. In recent years, researchers have extensively examined which genes and gene variants play a role in this, and have identified roughly one hundred obesity susceptibility genes. However, genome-wide association studies have shown that less than half of all cases of hereditary obesity can be explained by these genes. The other half are the result of factors that, although part of our DNA, are not genes in the classical sense. Epigenetic information would be one example of such a factor.

A group of researchers  have now identified a further non-classic genetic risk factor for hereditary obesity: an endogenous microRNA molecule known as microRNA-7. Like genes, the blueprints for microRNA molecules are part of our chromosomes. But while genes act as the building instructions for proteins, the information contained in microRNA is not translated into protein form. Instead, the microRNA molecules act in our cells in the form of RNA.

MicroRNA-7 is the first microRNA for which they have been able to demonstrate an association with obesity.

Mary P. LaPierre et al, MicroRNA-7 regulates melanocortin circuits involved in mammalian energy homeostasis, Nature Communications (2022). DOI: 10.1038/s41467-022-33367-w

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

The researchers  found that blood stem cells do not age uniformly. Rather, they are very heterogeneous and exhibit mixed populations. Thus, it was possible to isolate subpopulations from old mice in which the cells were predominantly old, but also populations in which the cells were in a "youth-like" state. The gene expression pattern of these cells also tended to resemble those of young hematopoietic stem cells. This is an indication that TAZ can to some extent counteract the gradual loss of stem cell function and protect blood stem cells by rejuvenating them. Consequently, genetic downregulation of TAZ in old HSCs resulted in a drastic failure to restore the blood system upon transplantation of these HSCs.

Kyung Mok Kim et al, Taz protects hematopoietic stem cells from an aging-dependent decrease in PU.1 activity, Nature Communications (2022). DOI: 10.1038/s41467-022-32970-1

Part 2

**

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

TAZ protein protects from age-related loss of function of blood stem cells

A well-functioning immune system is essential for protection against infections. However, with increasing age, the functioning of the immune system diminishes, which is also due to age-related damage in hematopoietic (blood) stem cells. Researchers have now discovered how the co-activator of the Hippo signaling pathway, the TAZ protein, can protect hematopoietic stem cells from aging and thus prevent them from loss of function. Moreover, hematopoietic stem cells age very heterogeneously. In addition to old cells, one can also find "youthful" cells when the protective mechanism has worked effectively.

Our blood is constantly being regenerated from hematopoietic stem cells (HSCs). With increasing age, however, these blood stem cells experience a loss of function and their regenerative potential diminishes. In older people, there is another problem with blood formation (hematopoiesis): they form fewer lymphocytes (cells of the immune system), so they are often no longer able to cope as well with infections and usually do not show a highly effective immune response after a vaccination.

There are already numerous indications that these deficiencies associated with old age result primarily from age-related damage in the blood stem cells. How this damage occurs, and whether there are protective mechanisms that could possibly protect the blood stem cells from it, is not yet known. In a study recently published in Nature Communications, researchers have now used novel analytical mehtods at the single cell level to investigate in more detail what happens during the aging process in hematopoietic stem cells and what role the TAZ protein plays in this process.

The adult body replaces billions of cells every day; in this process, existing cells are continuously replaced by "new" cells. "Maintaining the balance between cell division, cell differentiation and cell death is tremendously important, because even the smallest imbalances disturb this equilibrium and sooner or later contribute to the development of cancer or can lead to premature aging.

Part 1

Comment by Dr. Krishna Kumari Challa on October 9, 2022 at 11:58am

How To Make Yourself FLOAT!

Magic? Not really!

Comment by Dr. Krishna Kumari Challa on October 8, 2022 at 9:50am

Light-based therapy weakens antibiotic-resistant bacteria

Antibiotics are standard treatments for fighting dangerous bacterial infections. Yet the number of bacteria developing a resistance to antibiotics is increasing. Researchers  are overcoming this resistance with light.

The researchers tailored antimicrobial photodynamic therapy (aPDT)—a chemical reaction triggered by visible light—for use on antibiotic-resistant bacteria strains. Results showed the treatment weakened bacteria to where low doses of current antibiotics could effectively eliminate them.

The researchers began their work by choosing the bacteria and the three main parts of aPDT needed to combat it: molecular oxygen, light, and a photosensitizer—something that creates a reaction between oxygen and light. An already FDA-approved dye called methylene blue served as the photosensitizer. The light sources were specially constructed panels of 25 LEDs in reflective cones built by the Technical Support Laboratory of the São Carlos Institute of Physics. Methicillin-resistant Staphylococcus aureus served as the bacteria, and the researchers grew cultures with the blue dye in them to ensure the photosensitizer alone would not affect the bacteria.

At first, the team used aPDT by itself at various light strengths, durations, and in a specific series of follow-up treatments to log the bacteria's response. The idea was to find the lowest dose and shortest series that could weaken the bacterial membranes and other resistance mechanisms. Cell recoveries and reproductions revealed how many generations it took before antibiotic resistance returned. Next, the researchers added measured levels and combinations of antibiotics at different time intervals after aPDT treatments to note the weakened bacteria's responses.

Jace A. Willis et al, Breaking down antibiotic resistance in methicillin-resistant Staphylococcus aureus : Combining antimicrobial photodynamic and antibiotic treatments, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2208378119

Comment by Dr. Krishna Kumari Challa on October 8, 2022 at 8:55am

What your breath could reveal about your health

Comment by Dr. Krishna Kumari Challa on October 7, 2022 at 8:33am

Why Does Salt Change the Taste of Everything?

If your coffee is too bitter, add a pinch of salt. If your salad isn’t sour enough, add a pinch of salt. If your beer is too bitter, add a pinch of salt. Salt has a seemingly magical ability to enhance good flavors and dampen bad ones.

• ‹ Previous
• 1
• …
• 431
• 432
• 433
• 434
• 435
• …
• 1052
• Next ›
• Page