Comment

Comment by Dr. Krishna Kumari Challa yesterday

First report of wound treatment by a wild animal using a pain-relieving plant

Even though there is evidence of certain self-medication behaviours in animals, so far it has never been known that animals treat their wounds with healing plants.

Now biologists have observed this in a male Sumatran orangutan who sustained a facial wound. He ate and repeatedly applied sap from a climbing plant with anti-inflammatory and pain-relieving properties commonly used in traditional medicine. He also covered the entire wound with the green plant mesh. Thus, medical wound treatment may have arisen in a common ancestor shared by humans and orangutans.

While sick and avoidance behavior can be regularly observed in non-human animals, self-medication in the form of ingestion of specific plant parts is widespread in animals but exhibited at low frequencies. The closest relatives to humans, the great apes, are known to ingest specific plants to treat parasite infection and to rub plant material on their skin to treat sore muscles.

Recently a chimpanzee group in Gabon was observed applying insects to wounds. However, the efficiency of this behavior is still unknown. Wound treatment with a biologically active substance has so far not been documented.

In a study published in Scientific Reports, cognitive and evolutionary biologists from  report evidence of active wound treatment with a healing plant in a wild male Sumatran orangutan.

Part 1

Comment by Dr. Krishna Kumari Challa yesterday

The brain structure that produces norepinephrine also helps control visual attention

The locus coeruleus (LC) is a small region of the brainstem that produces norepinephrine, a chemical with powerful effects on arousal and wakefulness which plays an important role in the body's response to stress or panic. Now, research shows it plays a specific role in visual sensory processing as well.

In a study, titled "Locus coeruleus norepinephrine selectively controls visual attention" and published in Neuron, neuroscientists artificially increased neuronal activity in the LC by briefly shining light on genetically modified neurons. They saw that this manipulation selectively enhanced performance in non-human primates performing a visual attention task, underscoring the crucial role that attention plays in sensory perception.

Researchers now have found a brain structure that has strong signals related to whether the subjects are paying attention to a stimulus or not, and they see big differences in how its neurons respond depending on where that attention is directed.

Previous research has shown that LC activation, coupled with its ensuing norepinephrine production, might improve performance on tasks that require attention to discern between visual stimuli.

Distinguishing the effects of attention from other factors, like decision-making or motor movements, is crucial. 

 Those processes take place in other parts of the brain, and can contribute to performance independently. Understanding how a relatively small brain structure like the LC impacts such an important function as attention is also one step toward solving the overall puzzle of the brain.

Locus coeruleus norepinephrine contributes to visual spatial attention by selectively enhancing perceptual sensitivity, Neuron (2024). DOI: 10.1016/j.neuron.2024.04.001. www.cell.com/neuron/fulltext/S0896-6273(24)00239-3

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Comment by Dr. Krishna Kumari Challa yesterday

Testing for residual cancer cells before blood cell transplant therapy is important and practical, new study finds

Patients in remission after battling a high-risk blood cancer are likely to have better outcomes if no trace of the cancer is detectable before the patients receive donor blood cells.

The finding appearing in JAMA Oncology emphasizes the importance and practicality of testing for measurable residual disease (MRD)—a condition that refers to evidence of lingering cancer cells in the body after people receive apparently successful chemotherapy treatment in adults with acute myeloid leukemia.

The good news is this testing is doable.  You don't need to be at a specialized center with customized technology and high levels of expertise—testing can be done using commercially available kits potentially at any major modern hospital lab. It is now a matter of implementation.

In a study of 537 patients with AML treated throughout the United States, scientists used a method called targeted ultra-deep DNA sequencing to see if they could find specific, leftover cancer-related gene mutations in the blood of patients who were in remission, but still awaiting a bone marrow transplant from donors to restore their healthy blood supply.
The scientists were looking at DNA in blood for mutations in the FLT3 gene, which is among the most common seen in patients with AML. They found that if as little as 1 in 10,000 molecules of DNA tested contained a mutation, it corresponded with a higher risk of the cancer returning, and lower chances of survival with current standard treatments.

Measurable Residual FLT3-ITD before Allogeneic Transplant for Acute Myeloid Leukemia, JAMA Oncology (2024). DOI: 10.1001/jamaoncol.2024.0985

Comment by Dr. Krishna Kumari Challa yesterday

The authors propose that the weakened magnetic field may have allowed more hydrogen to escape to space, resulting in a greater percentage of oxygen in Earth's atmosphere and oceans, which may in turn have supported the diversification in the types and complexity of organisms.

John Tarduno, Near-collapse of the geomagnetic field may have contributed to atmospheric oxygenation and animal radiation in the Ediacaran Period, Communications Earth & Environment (2024). DOI: 10.1038/s43247-024-01360-4. www.nature.com/articles/s43247-024-01360-4

Part 2

Comment by Dr. Krishna Kumari Challa yesterday

Weak magnetic field may have supported diversification of life on Earth

An unusual reduction in the strength of Earth's magnetic field between 591 and 565 million years ago coincided with a significant increase in the oxygen levels in the atmosphere and oceans, according to a paper published in Communications Earth & Environment. The authors propose that the weakening of the magnetic field may have led to the increase in oxygen, which is  thought to have supported the evolution of some of the earliest complex organisms.

Between 600 and 540 million years ago, life on Earth consisted of soft-bodied organisms known as the Ediacaran fauna, the earliest known complex multicellular animals. The fossil record shows that these organisms significantly diversified in complexity and type between 575 and 565 million years ago. Previous research has suggested that this diversification is linked to a significant increase in atmospheric and oceanic oxygen levels that occurred over the same period. However, it is not yet clear why this increase in oxygen occurred.

Researchers analyzed the magnetic properties of 21 plagioclase crystals, a common mineral in Earth's crust, which were extracted from a 591-million-year-old rock formation in Brazil. Plagioclase crystals contain tiny magnetic minerals that preserve the intensity of the Earth's magnetic field at the time they are formed.
Analysis of the crystals showed that at their point of formation, Earth's magnetic field was the weakest ever recorded—some 30 times weaker than both the current magnetic field intensity, and that measured from similar crystals formed approximately 2,000 million years ago.
The authors combined their results with previous measurements to establish that the Earth's magnetic field was at this weak level for at least 26 million years, from 591 to 565 million years ago. This overlaps with the rise in oxygen, which occurred between 575 and 565 million years ago.

Part 1

Comment by Dr. Krishna Kumari Challa yesterday

Male chicks play more than females!

Play is widespread, but far from ubiquitous, across the animal kingdom. Especially common in mammals, play is also known to occur in taxa as diverse as birds, fish, octopuses, and even insects. But what is its function, given that natural selection never selects fun for its own sake? One prominent hypothesis is that play is beneficial to individuals because it allows them to practice skills needed later in life.

Now, a study in Frontiers in Ethology has shown that male baby chickens play far more than females. This result is of interest given that domestic chickens are directly descended from a species—red jungle fowl—with a pronounced difference between the sexes in morphology, coloration, and behaviour.

This difference is mainly because males engage more in social and object play.

The researchers distinguished 12 distinct play behaviors. Examples of locomotor play were frolicking and wing flapping. Object play included chasing an object or pecking at it or exchanging it with another chick. Social play included sparring, jumping, and sparring stand-offs.

Object play was more frequently seen than social play, while locomotor play was least common. Both females and males showed every type of playful behavior. However, the frequency of play differed between them: male chicks played more overall than females. This was due to males engaging more often in object and social play, while there was no difference between the sexes in the frequency of locomotor play.

The researcher concluded that these sex differences in chicks in the frequency of play can be explained by the high degree of sexual dimorphism of adult junglefowl. This means that male chicks would benefit more from practicing various skills related to physical ability and social tactics.

The present study indicates that a possible function is to prepare animals for specific challenges they may encounter later in life. In a species like the chicken, where only males compete for territories, it makes sense that they engage in more social play as young.

Rebecca Oscarsson et al, Male chicks play more than females—sex differences in chicken play ontogeny, Frontiers in Ethology (2024). DOI: 10.3389/fetho.2024.1392378. www.frontiersin.org/articles/1 … ho.2024.1392378/full

Comment by Dr. Krishna Kumari Challa yesterday

Researchers develop near-chromosome-level genome for the Mojave poppy bee

Scientists have developed a near chromosome-level genome for the Mojave poppy bee, a specialist pollinator of conservation concern, according to a recent paper published in the Journal of Heredity.

Putting together the Mojave poppy bee genome is part of the Beenome100 project, a first-of-its-kind effort to create a library of high-quality, highly detailed genome maps of 100 or more diverse bee species.

The expectation is that these genomes will help researchers answer the big questions about bees, such as what genetic differences make a bee species more vulnerable to climate change or whether a bee species is likely to be more susceptible to a pesticide.

The Mojave poppy bee and Las Vegas bearpoppy are also being considered for listing under the Endangered Species Act. Both species will be evaluated for potential declining populations and vulnerability to extinction due to climate change and to habitat loss from urban development and mining in their native region.

Researchers assembled the genome or genetic map that will help further to understand the Mojave poppy bee's biological traits.

The genome, with additional genetic sampling of individuals, will also potentially give us insights into the genetic basis for host-plant specialization, susceptibility to pesticides, and susceptibility to drought and climate tolerance.

Rena M Schweizer et al, Reference genome for the Mojave poppy bee (Perdita meconis), a specialist pollinator of conservation concern, Journal of Heredity (2023). DOI: 10.1093/jhered/esad076

Comment by Dr. Krishna Kumari Challa on Thursday

Based on previous work by other teams, the researchers selected a few candidate enzymes made by the gut bacterium Akkermansia muciniphila and treated red blood cells – from multiple donors and various A and B subtypes – with them.

Importantly, for potential clinical use, the enzymes were incubated with high concentrations of red blood cells, at room temperature and for only 30 minutes – improving on the longer processing and less efficient conditions of previous candidates.

"These mild conditions without additives (for example, dextran) together with excellent enzyme efficacies are important feasibility parameters in clinical applications.
Crucially, the chosen enzymes also removed all four known extensions of group A and B antigens from red blood cells, in addition to the shorter, canonical A and B antigens of other blood subtypes.

Removing the long, sugary extensions reduced the incompatibility of treated B-type cells with plasma samples to less than 9 percent, and made reactions less severe where they did happen.

More work is required to understand why a small fraction of apparently sugarless red blood cells still cross-react with group O plasmas, and to improve the conversion of group A blood cells.

However, in finding enzymes that remove a greater variety of A and B antigens, the researchers say their study uncovers "a missing link" in the production of universal blood for transfusion and potentially organs for transplantation.

In 2022, researchers used a similar strategy (with different enzymes) to convert donated lungs from group A blood type to the universal type O under lab conditions. This new work might improve those efforts enough to satisfy the safety standards required for human transplant trials.
Lab-grown red blood cells are also in human trials to test whether they last longer than donated blood. If so, that could reduce the demand on blood supplies and also help patients requiring repeat transfusions avoid complications.

https://www.nature.com/articles/s41564-024-01663-4

Part 3

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Comment by Dr. Krishna Kumari Challa on Thursday

What's tricky is that there are now, as of 2022, more than 40 blood group systems beyond the ABO system and rhesus factor most are familiar with.

Even within the A and B blood groups, there are subtypes, with varying lengths and densities of the signature molecules protruding from the red cells' membranes.
Scientists recently reported the discovery of remarkably efficient enzymes, not only against A and B antigens but also against their extensions.

published paper

Part 2

Comment by Dr. Krishna Kumari Challa on Thursday

Enzymes Discovered in Gut Bacteria Can Change a Donor's Blood Groups

When a life hangs in the balance, blood transfusions can help sustain a patient – but only if the donor's blood type is a match.
A new discovery by researchers from Denmark and Sweden could help in those emergency situations, while also easing global shortages in blood supplies.
The team identified a mixture of enzymes made by a species of bacteria found in our guts that can, in lab studies, transform red blood cells into the universal type O with "remarkably high efficiencies" – improving on an idea hatched 40 years ago.

Like virtually all cells in the human body, red blood cells are covered in a fuzz of unique sugary structures. These vary from person to person, with some sporting type A structures and others type B. Some have both A and B, and others have neither, which is designated O.

Immune systems that have never seen types A or B will attack and destroy these cells on sight if they receive them in a transfusion, whereas type O blood is far more widely accepted for most recipients.

Because of this versatility, type O blood stocks are often used up, especially in medical emergencies where doctors must act quickly without knowing a patient's blood type.
Converting red blood cells into the universal type O is not a new idea. The technique was pioneered back in 1982, when scientists discovered an enzyme extracted from coffee beans that could strip type B cells of their surface sugars.

But that enzyme reaction was very inefficient, making large-scale use impractical, and despite early promise in clinical trials, safety concerns were raised. For unknown reasons, donor blood was sometimes still incompatible in recipients despite donor cells being stripped of nearly all their antigens.

So scientists went back to the drawing board, discovering other enzymes in collections of gut bacteria as recently as 2019.
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