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Comment by Dr. Krishna Kumari Challa on March 8, 2023 at 11:33am

International Women's Day 2023 - "DigitALL: Innovation & Technology for Gender Equality"

Comment by Dr. Krishna Kumari Challa on March 7, 2023 at 11:28am

Trapping and killing superbugs with novel peptide 'nanonets'

Scientists have developed synthetic peptide nanonets for treating infections by bacteria strains resistant to last-resort antibiotics.

In nature, trap-and-kill is a common immune defense mechanism employed by various species, including humans. In response to the presence of pathogens, peptides are released from host cells and they promptly self-assemble in solution to form cross-linked nanonets, which then entrap the bacteria and render them more vulnerable to antimicrobial components.

Several research groups have explored synthetic biomimetics of nanonets as an avenue for addressing the global healthcare challenge of widespread antibiotic resistance. However, most prominent studies in the field only yielded disjointed short nanofibrils restricted to the bacterial surfaces and are incapable of physically immobilizing the bacteria. Additionally, these designs were lacking in control over the initiation of the self-assembly process.

A research team has now designed short β-hairpin peptides of 15 to 16 residues that are capable of self-assembling into nanonets selectively in response to lipopolysaccharide or lipoteichoic acid, which are integral membrane components unique to bacteria.
This specificity towards bacteria is an appealing attribute not yet achieved in the field. The peptide nanonets displayed both trapping and antimicrobial killing functionalities, thus offering a direct upgrade from the trap-only nanonets in nature as well as synthetic designs reported in the field. This opens up opportunities for modulating the activity spectrum of the material.
Nhan Dai Thien Tram et al, Bacteria‐Responsive Self‐Assembly of Antimicrobial Peptide Nanonets for Trap‐and‐Kill of Antibiotic‐Resistant Strains, Advanced Functional Materials (2022). DOI: 10.1002/adfm.202210858

Comment by Dr. Krishna Kumari Challa on March 7, 2023 at 10:32am

New treatment of autoimmune diseases revealed in new study

Scientists  have revealed a chemical compound that could be used for the treatment of various autoimmune diseases like multiple sclerosis and rheumatoid arthritis. These diseases occur when the body's immune response goes awry. The immune system, which normally attacks pathogens and infections, instead attacks healthy cells and tissues. For the millions of people who suffer from autoimmune diseases worldwide, the result can be debilitating—rheumatoid arthritis causes excessive joint pain, while multiple sclerosis can disable one's brain and spinal cord function.

The research focused on T helper 17 cells, or Th17 cells. Th17 cells are a type of T cell—a group of cells, which form major parts of the immune system. These cells, which exist in high numbers in our guts, evolved to help us fight invasive pathogens but, sometimes, they're overactivated and mistake normal, healthy tissue as pathogens, resulting in autoimmunity. The generation of Th17 cells requires glycolysis, a metabolic process in which glucose is broken down and converted to energy to support the metabolic needs of cells. Glycolysis is essential for the growth of not only Th17 cells but also a variety of cells in our body.

 Excessive glycolysis seems to suppress Th17 cell activity. So scientists hypothesized that molecules produced during glycolysis may inhibit the cells.

Enter phosphoenolpyruvate, or PEP for short. This chemical compound  is a metabolite produced when glucose is converted to energy. Since it is part of such an important process, PEP is generated every day in our bodies. The researchers found that treatment with PEP can inhibit the maturation of TH17 cells, leading to resolution of inflammatory response.

The research led to a protein called JunB, which is essential for the maturation of Th17 cells. JunB promotes Th17 maturation by binding to a set of specific genes. The researchers found that PEP treatment inhibits the generation of Th17 cells by blocking JunB activity.

Armed with this knowledge, the researchers went on to treat mice that had neuroinflammation caused by autoimmunity with PEP. This disease is very similar to multiple sclerosis and these mice showed positive signs of recovery. The scientists have now filed a patent to continue with this research.

Tsung-Yen Huang et al, Phosphoenolpyruvate regulates the Th17 transcriptional program and inhibits autoimmunity, Cell Reports (2023). DOI: 10.1016/j.celrep.2023.112205

In the past, researchers who were interested in developing a treatment for autoimmune diseases, often looked at inhibiting glycolysis and thus Th17 cells. But glycolysis is essential to various types of cells in the body and inhibiting it could have significant side-effects. PEP has the potential to be used as a treatment without resulting in such side-effects.

Comment by Dr. Krishna Kumari Challa on March 6, 2023 at 3:53pm

Plasticosis may be the first wildlife disease connected to plastics, but it may not be the last.

https://www.sciencedirect.com/science/article/pii/S0304389423003722...

Part 3

Comment by Dr. Krishna Kumari Challa on March 6, 2023 at 3:53pm

In the hardened and inflexible stomach of a plastic-filled shearwater, room for new food is limited and digestion seems to be severely impacted. With so much scar tissue, scientists say the lining of the internal organ is not nearly as good at secreting digestive enzymes or absorbing nutrients.

The resulting loss of nourishment could be a key reason why so many shearwaters on Lord Howe are underweight. Since 2010, their average body mass has plummeted. And in the current study, higher numbers of plastic pieces in a shearwater's stomach were associated with a lower overall body weight.

"The tubular glands, which secrete digestive compounds, are perhaps the best example of the impact of plasticosis.

"When plastic is consumed, these glands get gradually more stunted until they eventually lose their tissue structure entirely at the highest levels of exposure."

The consequences of ingesting plastic may not be the same for all seabird stomachs, or even all animal stomachs, but given the ubiquitous nature of ingested plastic in the marine food web, there's reason to worry about the health effects.

In humans, recent studies have shown people with inflammatory bowel disease (IBD) tend to have elevated levels of microplastics in their feces.

Among 52 participants, greater plastic exposure was closely aligned with the worst IBD symptoms.

That study was only small and does not establish cause and effect, but since microplastics have been found in human blood, placenta, feces, and the deepest parts of our lungs, toxicologists say we need urgent health assessments.

Ingested plastic can not only cause physical damage, it can also provide a way for parasites and microbes to hitchhike into the body. In addition, as plastics degrade, they may leech toxic and persistent chemicals with potentially dangerous health effects.

Part 2

Comment by Dr. Krishna Kumari Challa on March 6, 2023 at 3:51pm

'Plasticosis': The First Disease Caused by Ingested Plastic Was Just Described by Scientists

One of the most plastic-contaminated birds in the whole world is silently suffering from a novel, emerging disease scientists have coined 'plasticosis'.

It's reportedly the first time researchers have ever documented and quantified the pathological effects of ingested plastic in wild animals, and it's got scientists stressing about the health of more than just one species.

The new findings suggest sharp plastic fragments can literally tear some seabirds apart from the inside.

This new  study clearly demonstrates the ability of plastic to directly induce severe, organ-wide scar tissue formation or 'plasticosis' in wild, free-living animals, which is likely to be detrimental to individual health and survival, acccording to reporters. 

When it comes to physical damage caused by ingested plastic, flesh-footed shearwaters (Ardenna carneipes) are the canaries in the coal mine.

Despite the sheer distance from human civilization, many of the chicks hatched on Lord Howe are suffering a slow and sickly death that seems to be all our fault.

Each autumn, gaunt and bedraggled fledglings litter the island's beaches, and for years now, scientists have been trying to figure out why so many of these seabirds are sick and dying.

When researchers examined the carcasses of dozens of dead birds from Lord Howe, they found excessive and irreversible signs of scar tissue in stomach after stomach. The extensive internal scarring is most likely caused by tiny bits of sharp plastic digging into a bird's internal lining over and over. Without the chance to heal, the first chamber of the bird's stomach, called the proventriculus, grows distorted with damage.

Sometime back researchers described about a bird stomach so full of plastic it was "bulging… almost rupturing". The scientists conducting the necropsy counted 202 plastic pieces in total.

That's hardly an exceptional circumstance. Roughly 90 percent of necropsied birds on Lord Howe island have contained plastic in their stomachs.

The consistent scarring and chronic inflammation observed in seabird stomachs filled with plastic has scientists thinking this is a specific fibrotic disease.

They've called it 'plasticosis' to keep in line with other fibrotic diseases, like silicosis and asbestosis, which are also marked by tissue damage from pollutants, except in these cases the damage occurs in the lungs.

lab studies have shown that sharp, ingested macroplastics, around 5 millimeters in size, can block, ulcerate, or perforate digestive tracts, while also reducing feeding behavior. In severe cases, the animal can even starve to death.

The study among shearwaters is the first to show plasticosis occurring among wild animals.

Part 1

Comment by Dr. Krishna Kumari Challa on March 5, 2023 at 2:35pm

Scientists found a way to generate new neurons in the brain

Some areas of the adult brain contain quiescent, or dormant, neural stem cells that can potentially be reactivated to form new neurons. However, the transition from quiescence to proliferation is still poorly understood. A research team  has discovered the importance of cell metabolism in this process and identified how to wake up these neural stem cells and reactivate them.

Biologists succeeded in increasing the number of new neurons in the brain of adult and even elderly mice. These results, promising for the treatment of neurodegenerative diseases, are to be discovered in the journal Science Advances.

Stem cells have the unique ability to continuously produce copies of themselves and give rise to differentiated cells with more specialized functions. Neural stem cells (NSCs) are responsible for building the brain during embryonic development, generating all the cells of the central nervous system, including neurons.

Surprisingly, NSCs persist in certain brain regions even after the brain is fully formed and can make new neurons throughout life. This biological phenomenon, called adult neurogenesis, is important for specific functions such as learning and memory processes. However, in the adult brain, these stem cells become more silent or "dormant" and reduce their capacity for renewal and differentiation.

As a result, neurogenesis decreases significantly with age. Researchers have uncovered a metabolic mechanism by which adult NSCs can emerge from their dormant state and become active again.

They found that mitochondria, the energy-producing organelles within cells, are involved in regulating the level of activation of adult NSCs.

 The mitochondrial pyruvate transporter (MPC), a protein complex discovered eleven years ago, plays a particular role in this regulation. Its activity influences the metabolic options a cell can use. By knowing the metabolic pathways that distinguish active cells from dormant cells, scientists can wake up dormant cells by modifying their mitochondrial metabolism.

Biologists have blocked MPC activity by using chemical inhibitors or by generating mutant mice for the Mpc1gene. Using these pharmacological and genetic approaches, the scientists were able to activate dormant NSCs and thus generate new neurons in the brains of adult and even aged mice.

These results shed new light on the role of cell metabolism in the regulation of neurogenesis. In the long term, these results could lead to potential treatments for conditions such as depression or neurodegenerative diseases.

Francesco Petrelli, Valentina Scandella, Sylvie Montessuit, Nicola Zamboni, Jean-Claude Martinou, Marlen Knobloch. Mitochondrial pyruvate metabolism regulates the activation of quiescent adult neural stem cells. Science Advances, 2023; 9 (9) DOI: 10.1126/sciadv.add5220

Comment by Dr. Krishna Kumari Challa on March 5, 2023 at 2:02pm

Hubble’s Inside The Image: V838

Comment by Dr. Krishna Kumari Challa on March 4, 2023 at 2:10pm

6174 is known as Kaprekar's constant after the Indian mathematician D. R. Kaprekar. This number is renowned for the following rule:

1. Take any four-digit number, using at least two different digits (leading zeros are allowed).
2. Arrange the digits in descending and then in ascending order to get two four-digit numbers, adding leading zeros if necessary.
3. Subtract the smaller number from the bigger number.
4. Go back to step 2 and repeat.

The above process, known as Kaprekar's routine, will always reach its fixed point, 6174, in at most 7 iterations. Once 6174 is reached, the process will continue yielding 7641 – 1467 = 6174. For example, choose 1459:

9541 – 1459 = 8082

8820 – 0288 = 8532

8532 – 2358 = 6174

7641 – 1467 = 6174

The only four-digit numbers for which Kaprekar's routine does not reach 6174 are repdigits such as 1111, which give the result 0000 after a single iteration. All other four-digit numbers eventually reach 6174 if leading zeros are used to keep the number of digits at 4. For numbers with three identical numbers and a fourth number that is one number higher or lower (such as 2111), it is essential to treat 3-digit numbers with a leading zero; for example: 2111 – 1112 = 0999; 9990 – 999 = 8991; 9981 – 1899 = 8082; 8820 – 288 = 8532; 8532 – 2358 = 6174.

6174 (number) - Wikipedia

Comment by Dr. Krishna Kumari Challa on March 4, 2023 at 1:25pm

Black Hole Mergers

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