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Comment by Dr. Krishna Kumari Challa on July 23, 2024 at 12:35pm

New study identifies two proteins that may contribute to stroke recurrence

People who experience an arterial ischemic stroke (AIS) or transient ischemic stroke (TIA) are at an increased risk of suffering a second stroke or other major adverse cardiovascular event (MACE), making it critically important to identify risk factors and treatments to prevent these subsequent occurrences.

A new study has identified new genetic and molecular risk factors that may reveal new pathways for treating patients after they experience their first stroke.

Published in Stroke, the study identified CCL27 and TNFRSF14, two proteins that are associated with subsequent MACE, but not initial strokes. These proteins are known to activate inflammation, which plays a key role in the development of strokes and many chronic conditions and diseases.

The findings suggest that inflammation is a contributing factor to MACE outcomes among people after they have their first stroke.

Utilizing genetic information and medical history data from two large biobanks, the VA's Million Veteran Program and UK Biobank, the research team conducted ancestry-specific genome-wide association studies (GWAS) to find associations between DNA and incident and subsequent AIS and MACE.

GWAS are typically performed to determine whether individuals have had a medical event for the first time, but applying this method to subsequent MACE events could shed novel insights about stroke progression, information that would be valuable for therapeutic drug identification, the researchers say.

Protein Identification for Stroke Progression via Mendelian Randomization in Million Veteran Program and UK Biobank, Stroke (2024). DOI: 10.1161/STROKEAHA.124.047103

Comment by Dr. Krishna Kumari Challa on July 23, 2024 at 12:15pm

Scientists uncover fundamental rules for how dengue virus infects its mosquito and human hosts

Mosquito-borne viral infections once confined to tropical regions are spreading. Dengue virus infects up to 400 million people worldwide each year according to World Health Organization estimates, and no available treatments exist for this disease.

Now, research from the Stowers Institute for Medical Research has uncovered surprising strategies for how dengue and hundreds of other viruses replicate in their hosts, with the potential to aid in developing novel antiviral treatments and vaccines.

Exposing Dengue’s Invasion Strategies

 Luciana A Castellano et al, Dengue virus preferentially uses human and mosquito non-optimal codons, bioRxiv (2023). DOI: 10.1101/2023.06.14.544804

Luciana A Castellano et al, Dengue virus preferentially uses human and mosquito non-optimal codons, Molecular Systems Biology (2024). doi.org/10.1038/s44320-024-00052-7

Comment by Dr. Krishna Kumari Challa on July 23, 2024 at 12:05pm

Smell of human stress can affect dogs' emotions, leading them to make more pessimistic choices

Dogs experience emotional contagion from the smell of human stress, leading them to make more 'pessimistic' choices, new research finds. 

Evidence in humans suggests that the smell of a stressed person subconsciously affects the emotions and choices made by others around them.

The researchers recruited 18 dog-owner partnerships to take part in a series of trials with different human smells present. During the trials, dogs were trained that when a food bowl was placed in one location, it contained a treat, but when placed in another location, it was empty.

Once a dog learned the difference between these bowl locations, they were faster to approach the location with a treat than the empty location. Researchers then tested how quickly the dog would approach new, ambiguous bowl locations positioned between the original two.

A quick approach reflected 'optimism' about food being present in these ambiguous locations—a marker of a positive emotional state—while a slow approach indicated 'pessimism' and negative emotion. These trials were repeated while each dog was exposed to either no odor or the odors of sweat and breath samples from humans in either a stressed (arithmetic test) or relaxed (listening to soundscapes) state.

Researchers discovered that the stress smell made dogs slower to approach the ambiguous bowl location nearest the trained location of the empty bowl. An effect that was not seen with the relaxed smell. These findings suggest that the stress smell may have increased the dogs' expectations that this new location contained no food, similar to the nearby empty bowl location.

Researchers suggest this 'pessimistic' response reflects a negative emotional state and could possibly be a way for the dog to conserve energy and avoid disappointment.

The team also found that dogs continued to improve their learning about the presence or absence of food in the two trained bowl locations and that they improved faster when the stress smell was present.

Parr-Cortes, Zoe ; Muller, Carsten T ; Talas, Laszlo et al, The odour of an unfamiliar stressed or relaxed person affects dogs' responses to a cognitive bias test, Scientific Reports (2024). DOI: 10.1038/s41598-024-66147-1

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Comment by Dr. Krishna Kumari Challa on July 23, 2024 at 9:57am

Biologists discover male elephants use infrasonic rumbles to signal 'let's go'

Bull elephants gather in the evening coolness to drink. After a spell, a senior male lifts his head and turns from the waterhole. With ears flapping gently, he lets out a deep, resonant rumble.

One by one, the others respond, their voices overlapping in a sonorous, infrasonic chorus that whispers across the savanna. This elephant barbershop quartet conveys a clear message: It's time to move on.

Gradually, the elephants shift, their massive bodies swaying as they follow their rumbling leader to the next stop on their nocturnal wanderings.

For the first time, scientists  have documented male elephants using "let's go" rumbles to signal the start of group departures from the Mushara waterhole in Etosha National Park, Namibia. The vocalizations are initiated by the most socially integrated, and often the most dominant, males in close-knit social groups.

The findings, detailed in the open-access journal PeerJ, are surprising because this behavior was previously thought to be exclusive to female elephants in family groups.

Male elephants, typically considered to have loose social ties, engaging in such sophisticated vocal coordination to trigger action is surprising. 

The "let's go" rumbles observed in male elephants bear striking similarities to those previously recorded in female elephants. The researchers hypothesized that male elephants likely learn the behaviour when they are young.

In the case of both male and female elephants, the initiator's call is followed by the next individual's rumble, with each elephant waiting for the preceding call to nearly finish before adding their own voice. This creates a harmonious, turn-taking pattern akin to a barbershop quartet.

It's very synchronized and ritualized. When one goes high, the other goes low, and they have this vocal space where they're coordinating.

PeerJ (2024). doi.org/10.7717/peerj.17767

Comment by Dr. Krishna Kumari Challa on July 22, 2024 at 10:36am

A second study by researchers also found evidence of long-lasting ovary proteins in young mice, including proteins that were present before the mice were born. Certain long-lasting proteins, such as ZP3, were identified for future studies.

Some of these hardy proteins were present in the cell mitochondria, where a cell's energy is generated. Since mitochondria are inherited as part of the egg cell a mammal grows from, it could ensure these critical organelles can remain functional as they're passed from mother to offspring.

Eventually, even these proteins that live way beyond the norm fade away and die, the researchers report. That could be connected to the natural decline in a woman's ability to have children, the study suggests – and could ultimately point to ways to treat or at least better diagnose infertility.

The findings from these studies of mice still need to be replicated in humans, but if they are, it would represent a significant step forward in our understanding of fertility and how oocytes can be kept in a healthy state.

https://elifesciences.org/reviewed-preprints/93172

https://www.nature.com/articles/s41556-024-01442-7

Part 2

Comment by Dr. Krishna Kumari Challa on July 22, 2024 at 10:34am

Ovarian Egg Cells Live an Unusually Long Time, And We Finally Know Why

Mammals are born with all the oocytes (or egg cells) they'll ever need, but how the cells remain alive and active for so long is something of a mystery. A pair of studies have now revealed it could all come down to the robustness of their proteins. The two investigations used traceable isotopes incorporated into growing mouse fetuses to measure the lifespans of proteins in their ovaries, finding many of them survived far longer than proteins in the rest of the body. The presence of these 'long life' molecules and the support they give oocytes and the surrounding cells seem to be crucial in maintaining fertility.
the first study analyzed oocytes in 8-week-old mice, when the animals were at their reproductive prime. Around 10 percent of the oocyte proteins produced while the animals were in utero were still present.

The researchers then looked at older mice to see how long it took for these persistent proteins to break down. The answer: not very quickly at all, relatively speaking. Some of the proteins remained in the ovaries of the mice for most of the animals' short lives.
The data establishes that many proteins in oocytes and the ovary are unusually stable, with half-lives well above those reported in other cell types and organs, including the liver, heart, cartilage, muscle and the brain.
The half-lives of many proteins are much higher in the ovary than in other organs, and many additional proteins are uniquely long-lived in the ovary.
Part 1

Comment by Dr. Krishna Kumari Challa on July 22, 2024 at 9:30am

NASA's Curiosity rover discovers yellow sulfur crystals in a Martian rock

On May 30th when a rock that NASA's Curiosity Mars rover drove over cracked open to reveal something never seen before on the Red Planet: yellow sulfur crystals.

Since October 2023, the rover has been exploring a region of Mars rich with sulfates, a kind of salt that contains sulfur and forms as water evaporates. But where past detections have been of sulfur-based minerals—in other words, a mix of sulfur and other materials—the rock Curiosity recently cracked open is made of elemental (pure) sulfur. It isn't clear what relationship, if any, the elemental sulfur has to other sulfur-based minerals in the area.

While people associate sulfur with the odor from rotten eggs (the result of hydrogen sulfide gas), elemental sulfur is odorless. It forms in only a narrow range of conditions that scientists haven't associated with the history of this location. And Curiosity found a lot of it—an entire field of bright rocks that look similar to the one the rover crushed.

It's one of several discoveries Curiosity has made while off-roading within Gediz Vallis channel, a groove that winds down part of the 3-mile-tall (5-kilometer-tall) Mount Sharp, the base of which the rover has been ascending since 2014. Each layer of the mountain represents a different period of Martian history. Curiosity's mission is to study where and when the planet's ancient terrain could have provided the nutrients needed for microbial life, if any ever formed on Mars.

Source: NASA

Comment by Dr. Krishna Kumari Challa on July 21, 2024 at 12:21pm

The Rarest Eye Colors in the World - Eye Colors Explained

Comment by Dr. Krishna Kumari Challa on July 21, 2024 at 12:17pm

Fire on Earth vs. in space - Gravity has more of an impact than you might think!

Comment by Dr. Krishna Kumari Challa on July 21, 2024 at 12:12pm

Comparing individual patient blood samples to their biopsies, the team identified 158 genes that were differentially expressed across all four organs during cases of rejection. That's nearly 20 times higher than what was expected by chance.

This discovery is pivotal as it allows us to develop strategies to enhance the success rates of all transplants.
Some of these shared biomarkers are involved in the secretion of proteins that stimulate white blood cells, enzymes that induce cell death, receptors on cells that allow materials in and out, and bone marrow cells involved in the immune response.
These findings demonstrate a "unifying pan-organ molecular marker".
The research team has made an interactive website that allows scientists around the world to compare possible biomarkers of transplant rejection against other methods, providing a much-needed standardized evaluation. This atlas has led to the development of a proof of principle for a universal blood test that can predict the likelihood of transplant rejection before it occurs.

https://www.nature.com/articles/s41591-024-03030-6

Part 2

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