Comment

Comment by Dr. Krishna Kumari Challa on August 3, 2023 at 11:42am

The membranes surrounding viruses are made of different molecules than the virus itself, as lipids are acquired from the host to form membranes. One such lipid, phosphatidylserine, is present in the membrane on the outside of viruses, but is sequestered towards the interior of human cells under normal conditions.

Because phosphatidylserine is found on the exterior of viruses, it can be a specific target for peptoids to recognize viruses, but not recognize—and therefore spare—our own cells. Moreover, because viruses acquire lipids from the host rather than encoding from their own genomes, they have better potential to avoid antiviral resistance.

The researchers tested seven peptoids against the four viruses. They found that the peptoids inactivated all three enveloped viruses—Zika, Rift Valley fever, and chikungunya—by disrupting the virus membrane, but did not disrupt coxsackievirus B3, the only virus without a membrane.

Moreover, chikungunya virus containing higher levels of phosphatidylserine in its membrane was more susceptible to the peptoids. In contrast, a membrane formed exclusively with a different lipid named phosphatidylcholine was not disrupted by the peptoids, suggesting that phosphatidylserine is crucial in order for peptoids to reduce viral activity.

The researchers are continuing pre-clinical studies to evaluate the potential of these molecules in fighting viruses and to understand if they can overcome the development of resistance. Their peptoid-focused approach may hold promise for treating a wide range of viruses with membranes that can be difficult to treat, including Ebola, SARS-CoV-2, and herpes.

 Peptidomimetic Oligomers Targeting Membrane Phosphatidylserine Exhibit Broad Antiviral Activity, ACS Infectious Diseases (2023). DOI: 10.1021/acsinfecdis.3c00063 , pubs.acs.org/doi/abs/10.1021/acsinfecdis.3c00063

Part 2

Comment by Dr. Krishna Kumari Challa on August 3, 2023 at 11:40am

Novel molecules fight viruses by bursting their bubble-like membranes

Antiviral therapies are notoriously difficult to develop, as viruses can quickly mutate to become resistant to drugs. Viruses have different proteins on their surfaces that are often the targets of therapeutics like monoclonal antibodies and vaccines. But targeting these proteins has limitations, as viruses can quickly evolve, changing the properties of the proteins and making treatments less effective. These limitations were on display when new SARS-CoV-2 variants emerged that evaded both the drugs and the vaccines developed against the original virus.

But what if a new generation of antivirals ignores the fast-mutating proteins on the surface of viruses and instead disrupts their protective layers?

Scientists found an Achilles heel of many viruses: their bubble-like membranes. Exploiting this vulnerability and disrupting the membrane is a promising mechanism of action for developing new antivirals.

In a new study published Aug. 2 in the journal ACS Infectious Diseases, the researchers show how a group of novel molecules inspired by our own immune system inactivates several viruses, including Zika and chikungunya. Their approach may not only lead to drugs that can be used against many viruses, but could also help overcome antiviral resistance.

Drawing inspiration from our immune system is the new mantra. Our innate immune system combats pathogens by producing antimicrobial peptides, the body's first line of defense against bacteria, fungi, and viruses. Most viruses that cause disease are encapsulated in membranes made of lipids, and antimicrobial peptides work by disrupting or even bursting these membranes. While antimicrobial peptides can be synthesized in the lab, they are rarely used to treat infectious diseases in humans because they break down easily and can be toxic to healthy cells. Instead, scientists have developed synthetic materials called peptoids, which have similar chemical backbones to peptides but are better able to break through virus membranes and are less likely to degrade. 

Part 1

Comment by Dr. Krishna Kumari Challa on August 2, 2023 at 1:09pm

Conjunctivitis is the swelling or inflammation of the conjunctiva, the thin, transparent layer of tissue that lines the inner surface of the eyelid and covers the white part of the eye. Causes may or may not be infectious. Allergic Conjunctivitis  ( seasonal allergies) Infectious Conjunctivitis  ( Bacterial, Viral ) Chemical Conjunctivitis ( air pollution, chlorine in water ) Ippudu ee season lo sadharanam ga vachedi viral or bacterial conjunctivitis. There are Eye drops or ointments  for Bacterial con. There are  Antibiotics too. But no drops or ointments can treat viral conjunctivitis. Antibiotics will not cure a viral infection. The virus has to run its course, which may take up to two or three weeks.  In case you have to deal with infectious people,  frequent hand washing and keeping hands away from eyes can make a difference. Don't use Common towels, soaps .Be Careful. If you feel  pain and irritation  please visit a doctor . Self medication is not good.

Comment by Dr. Krishna Kumari Challa on August 2, 2023 at 12:47pm

You shouldn't declaw tigers or other big cats

Declawing house cats to keep them from scratching people and furniture is controversial – and even banned in some countries  – but the practice is not limited to house cats. In a new study, researchers looked at the effects of declawing on larger cat species and found that declawing disproportionately impacts their muscular capabilities as compared to their smaller brethren.

Declawing is still done on large cats like lions and tigers, often in an effort to allow cubs to more safely be handled in photo opportunities or for entertainment purposes.

What people might not realize is that declawing a cat is not like trimming our fingernails; rather, it is removing part or all of the last bone of each digit. Like us, each cat finger has three bones, and declawing is literally cutting that third bone off at the joint.

The researchers looked at the muscular anatomy of over a dozen exotic cats – from smaller species including bobcats, servals and ocelots, to lions and tigers – to determine the effect of declawing on their forelimb musculature.

They measured muscle density and mass, and also examined muscle fibers from both clawed and declawed exotic cats. They found that for the larger species declawing resulted in 73% lighter musculature in the forearm’s digital flexors. These muscles are involved in unsheathing the claws. They also found that overall, forelimb strength decreased by 46% to 66%, depending on the size of the animal, and that other muscles in the forelimb did not compensate for these reductions.

With big cats, there’s more force being put through the paws. So if you alter them, it is likely that the effects will be more extreme.

This is because paw size and body mass don’t scale up at a 1:1 ratio. Paw area increases at a slower rate than does body mass (which is proportional to volume), so larger cats have smaller feet relative to their body size, and their paws must withstand more pressure.

Additionally, big cats are more reliant on their forelimbs – they bear most of the weight, and these bigger cats use their forelimbs to grapple because they hunt much larger prey. So biomechanically speaking, declawing has a more anatomically devastating effect in larger species.

Lara L. Martens et al, The Effects of Onychectomy (Declawing) on Antebrachial Myology across the Full Body Size Range of Exotic Species of Felidae, Animals (2023). DOI: 10.3390/ani13152462

Comment by Dr. Krishna Kumari Challa on August 2, 2023 at 10:12am

Is AI only software? 

AI is about the principles of making machines learn and make intelligent decisions. AI has many subfields under it: Machine Learning, Reinforcement Learning, Computer Vision (very tightly coupled with Machine Learning), Deep Learning, NLP, data representation and semantics, learning theory, Robotics (which is the hardware side of things) which includes things like planning, motion and manipulation...etc.

So its not only about software. AI can be in the form of abstract theory, learning from data to make predictions and intelligent decisions (software) or in robotics (hardware).

Comment by Dr. Krishna Kumari Challa on August 2, 2023 at 10:09am

Chatbots sometimes make things up. Is AI's hallucination problem fixable?

Spend enough time with ChatGPT and other artificial intelligence chatbots and it doesn't take long for them to spout falsehoods. 

Described as hallucination, confabulation or just plain making things up, it's now a problem for every business, organization and high school student trying to get a generative AI system to compose documents and get work done. Some are using it on tasks with the potential for high-stakes consequences, from psychotherapy to researching and writing legal briefs.

According to experts there isn't any model today that doesn't suffer from some hallucination! They're really just sort of designed to predict the next word, and so there will be some rate at which the model does that inaccurately. 

So experts are now trying to make them truthful. But they aren't very sure. Because the problem is inherent in the mismatch between the technology and the proposed use cases.

But still what is wrong with trying to improve the software/hardware? let us cross our fingers and hope for the best.

Source: AP 

Comment by Dr. Krishna Kumari Challa on August 2, 2023 at 9:56am

Early-life lead exposure linked to higher risk of criminal behaviour in adulthood

An evaluation of 17 previously published studies suggests that exposure to lead in the womb or in childhood is associated with an increased risk of engaging in criminal behavior in adulthood. 

Lead exposure can cause a variety of health challenges, such as cardiac issues,kidney damage, immune system dysfunction, reproductive problems, and impaired neurodevelopmental function in children. Research has also uncovered statistical associations between lead exposure and criminal behaviour, both at the level of the entire population and at the level of individual people. However, the findings of individual-level studies have been inconsistent.

To help clarify the existing evidence, researchers conducted a systematic review of studies that address links between individual lead exposure and crime or other antisocial behaviors. Their analysis included 17 studies, which employed a variety of methods for measuring lead exposure—using blood, bones, or teeth—and addressed the effects of exposure at different ages, including in the womb or early childhood, later childhood, and adolescence or adulthood.

The review highlighted a wide range of findings among the studies. For instance, in some cases, no statistical links were found between early childhood lead exposure and later delinquent behavior. One study showed a link between exposure and antisocial behavior, but not arrests. Still, several studies found links between early childhood exposure to lead and later arrests, including drug-related arrests. The authors also used a tool called ROBINS-E to evaluate each study for statistical bias, finding some studies to be more statistically robust than others.

Overall, in light of the known biological effects of lead, this review suggests that an individual exposed to lead in the womb or in early childhood may have a higher risk of engaging in criminal behaviour as an adult.

Policy action to prevent lead exposure is of utmost importance as our research shows an excess risk for criminal behavior in adulthood exists when an individual is exposed to lead in utero or during childhood. Preventing lead exposure is crucial to safeguard public health and promote a safer society for all.

Talayero MJ, The association between lead exposure and crime: A systematic review, PLOS Global Public Health (2023). DOI: 10.1371/journal.pgph.0002177

Comment by Dr. Krishna Kumari Challa on August 1, 2023 at 12:47pm

Mysterious Creatures Feed Microbes to Their Babies in New Scientific First

Caecilian mothers grow a fatty skin layer for their babies to tear off and eat. It offers not only nourishment for their offspring but also microbes, providing a starter kit for their young's own microbiome, new research has discovered.

Caecilians are weird, mysterious creatures. They look sort of like huge worms or small snakes, but they're really limbless amphibians, lesser-known relatives of frogs and salamanders. They lead secretive lives, generally hidden from view in soil or stream beds.

What little we do know about caecilians invites more curiosity. They can be surprisingly doting parents, especially by amphibian standards. In some species, mothers provide the skin meals for their young, who have uniquely adapted baby teeth to help them eat it.

Many animals are known to pass microbes to the next generation through parental care in some way, but this is the first direct evidence of it happening in any amphibian. And of all the amphibian species it could be, the study's authors found this happening in caecilians.

 Even after the period of skin feeding (or maternal dermatophagy) ends, a mother and her babies often stay together, the researchers note, coiling up together as a family.

The study found that bacteria from the environment were the least important source for microbiomes of young caecilians. But all juveniles shared at least some of their skin and gut microbiomes with their mothers, which they obtained via both skin feeding and coiling.

https://animalmicrobiome.biomedcentral.com/articles/10.1186/s42523-...

Comment by Dr. Krishna Kumari Challa on August 1, 2023 at 12:21pm

Worms Revived After 46,000 Years Frozen in Siberian Permafrost

Scientists want to understand how the worms survived in extreme conditions for extraordinarily long periods of time.

The discovery, published  recently in the peer-reviewed journal PLOS Genetics, offers new insight into how the worms, also known as nematodes, can survive in extreme conditions for extraordinarily long periods of time, in this case tens of thousands of years.

In 2018, Anastasia Shatilovich, a scientist from the Institute of Physicochemical and Biological Problems in Soil Science RAS in Russia, thawed two female worms from a fossilized burrow dug by gophers in the Arctic.

The worms, which were buried approximately 130 feet in the permafrost, were revived simply by putting them in water, according to a news release from the Max Planck Institute of Molecular Cell Biology and Genetics in Germany.

Called Panagrolaimus kolymaensis, after the Kolyma River in Russia, where they were found, the worms were sent to Germany for further study. The creatures, which have a life span measured in days, died after reproducing several generations in the lab, researchers said.

Using radiocarbon dating, researchers determined the specimens were frozen between 45,839 and 47,769 years ago, during the late Pleistocene.

The roughly millimeter-long worms were able to resist extreme low temperatures by entering a dormant state called cryptobiosis, a process researchers at the institute have been trying to understand.

No nematodes had been known to achieve such a dormant state for thousands of years at a time, Teymuras Kurzchalia, a professor emeritus at the institute who was involved in the study, said recently.

The major take-home message or summary of this discovery is that it is, in principle, possible to stop life for more or less an indefinite time and then restart it.

Researchers identified key genes in the nematode that allow it to achieve the cryptobiotic state. The same genes were found in a contemporary nematode called Caenorhabditis elegans, which can also achieve cryptobiosis.

This led researchers to understand that they cannot survive without a specific sugar called trehalose. Without this sugar, they just die.

The Siberian permafrost has long offered the scientific community a window into the organisms of the distant past. Ancient viruses, mummified bodies and a suite of microscopic creatures have been resurrected from the ice over the years.

“It is, in principle, possible to stop life for more or less an indefinite time and then restart it.”

Comment by Dr. Krishna Kumari Challa on August 1, 2023 at 11:56am

Such a "slowing down" is typical for phase transitions based on the excitation of bosons. Bosons are particles that "generate" interactions (on which, for example, magnetism is based). Matter, on the other hand, is not made up of bosons but of fermions. Electrons, for example, belong to the fermions.

Phase transitions are based on the fact that particles (or also the phenomena triggered by them) disappear. This means that the magnetism in iron becomes smaller and smaller as fewer atoms are aligned in parallel. Fermions, however, cannot be destroyed due to fundamental laws of nature and therefore cannot disappear. "That's why normally they are never involved in phase transitions."

Electrons can be bound in atoms; they then have a fixed place which they cannot leave. Some electrons in metals, on the other hand, are freely mobile—which is why these metals can also conduct electricity. In certain exotic quantum materials, both varieties of electrons can form a superposition state. This produces what are known as quasiparticles.

They are, in a sense, immobile and mobile at the same time—a feature that is only possible in the quantum world. These quasiparticles—unlike "normal" electrons—can be destroyed during a phase transition. This means that the properties of a continuous phase transition can also be observed there, in particular, critical slowing down. So far, this effect could be observed only indirectly in experiments.

Researchers have now developed a new method, which allows direct identification of the collapse of quasiparticles at a phase transition, in particular the associated critical slowing down.

The result contributes to a better understanding of phase transitions in the quantum world. On the long term, the findings might also be useful for applications in quantum information technology.

Critical slowing down near a magnetic quantum phase transition with fermionic breakdown, Nature Physics (2023). DOI: 10.1038/s41567-023-02156-7. www.nature.com/articles/s41567-023-02156-7

Part 2

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