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Comment by Dr. Krishna Kumari Challa on January 13, 2024 at 11:54am

Bizarre Galaxy Discovered With Seemingly No Stars Whatsoever

A newly discovered object is stretching our understanding of what constitutes a galaxy.

Called J0613+52, this massive blob of something some 270 million light-years away appears to have no stars whatsoever. At least, none that can be seen. It's just a haze made of the kind of gas that's found between stars in normal galaxies, drifting around by its lone self .

Its mass and motion appear to be normal for what we'd expect of a spiral galaxy… in fact, if you extracted the stars from a spiral galaxy like the Milky Way or Andromeda, J0613+52 is pretty much what you'd end up with.

According to a team of astronomers  it could be the first discovery of a primordial galaxy in the nearby Universe – a galaxy made up mostly of the gas that formed at the beginning of time.

The object appears to be isolated and undisturbed, having experienced no gravitational interactions over the 13.8 billion-year course that would have disrupted the gas, either tearing it apart, or pushing it into the clumps needed to trigger significant star formation. This makes J0613+52 an object unlike any other we've ever seen before.

It's a galaxy made only out of gas – it has no visible stars. Stars could be there, we just can't see them.

The discovery – one made purely by chance – has been presented at the 243rd meeting of the American Astronomical Society.

Comment by Dr. Krishna Kumari Challa on January 13, 2024 at 10:12am

To rectify this, the same research team has conducted a comprehensive analysis of age-related variations in microRNAs in mice sperm. They compared microRNAs in sperm from mice aged 3, 12, and 20 months and identified the microRNAs that had changed in quantity.

The researchers discovered significant age-associated differences in the microRNAs. Some changes were in microRNAs responsible for regulating the nervous system and genes related to autism spectrum disorder, and these altered microRNAs included those transferred to fertilized eggs.

The present study reveals the potential association between alteration in sperm microRNAs caused by paternal aging, underscoring the significance of investigating the impact of sperm microRNAs on offspring, an aspect that has been relatively overlooked in previous research.

The anticipation is that further exploration of epigenetic factors, specifically microRNAs, will not only contribute to unraveling the pathogenic mechanisms underlying neurodevelopmental disorders but will also offer insights into promoting the health and disease prevention of successive generations.

Kazusa Miyahara et al, Investigating the impact of paternal aging on murine sperm miRNA profiles and their potential link to autism spectrum disorder, Scientific Reports (2023). DOI: 10.1038/s41598-023-47878-z

Part 2

Comment by Dr. Krishna Kumari Challa on January 13, 2024 at 10:10am

Mouse study finds aging sperm affects microRNA, increasing the risk of neurodevelopmental disorders

A recent study has reported that changes in mice sperm microRNAs brought about by aging may affect the growth and development of offspring. The finding adds to the growing literature on the effects of paternal aging on offspring.

Marriages and childbearing later in life are increasingly becoming the norm. While the impacts of maternal age on offspring, such as a higher risk of miscarriage and Down syndrome, are widely understood, the impacts from the paternal side are less so. Yet this is changing.

Recent epidemiological studies have demonstrated that paternal aging exerts a more substantial influence on the heightened risk of neurodevelopmental disorders such as autism spectrum disorder.

A research team has Previously revealed* that epigenetic factors, including histone modifications in spermatogenesis and DNA methylation in mice sperm, undergo changes with age. These alterations might lead to transgenerational effects.

However, the impact of paternal aging on microRNAs (miRNAs), small, non-coding RNA molecules that play a crucial role in regulating gene expression, remains under-explored.

* Misako Tatehana et al. Comprehensive histochemical profiles of histone modification in male germline cells during meiosis and spermiogenesis: Comparison of young and aged testes in mice, PLOS ONE (2020). DOI: 10.1371/journal.pone.0230930

Part 1

Comment by Dr. Krishna Kumari Challa on January 12, 2024 at 11:46am

Even though CO₂ emissions on the whole decrease, significant differences exist between and among biomaterials, necessitating more action to achieve complete climate neutrality across the entire production chain. No material is 100% climate-neutral. Some are close, but others even emit more CO₂ than the fossil materials they replace.

Another consideration is that, despite reducing CO₂ emissions, the production of biomaterials may still cause other environmental impacts. For instance, through the use of fertilizers in the production of biomass used for biomaterials. This can lead to eutrophication: an excess of nutrients resulting in oxygen depletion in surface waters.

The researchers calculated that, on average, the production of biomaterials contributed to an increase in eutrophication impact. Reducing CO2 emissions is very important in mitigating climate change, however, we should avoid shifting the impact to other areas. Extra attention is therefore needed if we decide to transition to biomaterials on a large scale.

Emma A. R. Zuiderveen et al, The potential of emerging bio-based products to reduce environmental impacts, Nature Communications (2023). DOI: 10.1038/s41467-023-43797-9

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Comment by Dr. Krishna Kumari Challa on January 12, 2024 at 11:44am

Biomaterials contribute greatly to reduction of greenhouse gas emis...

On average, bio-based products emit 45% less greenhouse gas emissions than the fossil materials they replace, according to research conducted by Radboud University, published in Nature Communications. At the same time, there is a large variation between individual bio-based products and more efforts are required to achieve climate neutrality. Additionally, biomaterials may have less favorable environmental impacts in other areas.

On average, bio-based products emit 45% less greenhouse gas emissions than the fossil materials they replace, according to research conducted by  scientists, published in Nature Communications. At the same time, there is a large variation between individual bio-based products and more efforts are required to achieve climate neutrality. Additionally, biomaterials may have less favourable environmental impacts in other areas.

Globally, there is a lot of investment in developing new materials from biomass, commonly known as biomaterials, to mitigate CO₂ emissions from fossil materials. Biomaterials are derived from plants and are intended to replace materials made from fossil fuels, such as bio-plastics or bio-fibers (for clothing). It is assumed that biomaterials are better in terms of environmental impact.

Research shows that, on average, new biomaterials emit 45% less CO2 than their counterparts made from fossil fuels. The researchers analyzed data from 98 new biomaterials reported in 130 international studies. "These studies considered the entire chain: from raw material extraction, production itself, to the final waste processing.

Part 1

Comment by Dr. Krishna Kumari Challa on January 12, 2024 at 11:33am

Green and red cone cells are remarkably similar except for a protein called opsin, which detects light and tells the brain what colours people see. Different opsins determine whether a cone will become a green or a red sensor, though the genes of each sensor remain 96% identical. With a breakthrough technique that spotted those subtle genetic differences in the organoids, the researchers tracked cone ratio changes over 200 days.

The researchers also mapped the widely varying ratios of these cells in the retinas of 700 adults. Seeing how the green and red cone proportions changed in humans was one of the most surprising findings of the new research.

Retinoic acid signaling regulates spatiotemporal specification of human green and red cones, PLoS Biology (2024). DOI: 10.1371/journal.pbio.3002464. journals.plos.org/plosbiology/ … journal.pbio.3002464

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Scientists still don't fully understand how the ratio of green and red cones can vary so greatly without affecting someone's vision.

To build understanding of diseases like macular degeneration, which causes loss of light-sensing cells near the center of the retina, the researchers are working with other Johns Hopkins labs. The goal is to deepen their understanding of how cones and other cells link to the nervous system.

Part 2

Comment by Dr. Krishna Kumari Challa on January 12, 2024 at 11:30am

Lab-grown retinas explain why people see colours some animals can't

With human retinas grown in a petri dish, researchers discovered how an offshoot of vitamin A generates the specialized cells that enable people to see millions of colors, an ability that dogs, cats, and other mammals do not possess.

These retinal organoids allowed scientists for the first time to study this very human-specific trait. It's a huge question about what makes us human, what makes us different.

The findings, published in PLOS Biology, increase understanding of color blindness, age-related vision loss, and other diseases linked to photoreceptor cells. They also demonstrate how genes instruct the human retina to make specific color-sensing cells, a process scientists thought was controlled by thyroid hormones. By tweaking the cellular properties of the organoids, the research team found that a molecule called retinoic acid determines whether a cone will specialize in sensing red or green light. Only humans with normal vision and closely related primates develop the red sensor.

Scientists for decades thought red cones formed through a coin toss mechanism where the cells haphazardly commit to sensing green or red wavelengths—and research from researchers recently hinted that the process could be controlled by thyroid hormone levels. Instead, the new research suggests red cones materialize through a specific sequence of events orchestrated by retinoic acid within the eye.

The team found that high levels of retinoic acid in early development of the organoids correlated with higher ratios of green cones. Similarly, low levels of the acid changed the retina's genetic instructions and generated red cones later in development.

There still might be some randomness to it, but the big finding is that you make retinoic acid early in development.This timing really matters for learning and understanding how these cone cells are made.

Part1

Comment by Dr. Krishna Kumari Challa on January 12, 2024 at 10:06am

Copy and taste

There is still much that needs to be understood about the interplay of obvious enjoyment and the liking of food. For example, the researchers have focused on adults, and while this has not been tested for on this occasion, they said that given the power of negative facial expressions and because children tend to be less willing to try vegetables by default, these findings could generalize to kids.

"For example, if a child sees their parent showing disgust while eating vegetables, this could have negative consequences on children's vegetable acceptance.

In the present study, participants also watched short video clips rather than watching people eat in front of them. This allowed them to observe the dynamic nature of reactive facial expressions, which is more realistic than looking at static pictures; however, in the future, an important focus will be to examine the effect of watching live food enjoyment on eating behavior, the researchers said.

"We also need more research to see whether the findings from this study translate to adults' actual intake of vegetables.

Katie L. Edwards et al, Facial expressions and vegetable liking, Frontiers in Psychology (2024). DOI: 10.3389/fpsyg.2023.1252369

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Comment by Dr. Krishna Kumari Challa on January 12, 2024 at 10:04am

Watching others visibly dislike vegetables might make onlookers dislike them, too

Humans learn which behaviours pay off and which don't from watching others. Based on this, we may draw conclusions about how to act—or eat. In the latter's case, people may use each other as guides to determine what and how much to eat. This is called social modeling and is one of the most powerful social influences on eating behaviour.

In a new study, researchers  investigated whether observing others' facial expressions while eating raw broccoli influenced young women's liking and desire to eat raw broccoli.

They show that watching others eating a raw vegetable with a negative facial expression reduces adult women's liking of that vegetable, but not their desire to eat it. This highlights the power of observing food dislike on adults' eating behaviour. 

Previous research shows that behaviors are more likely to be imitated if positive consequences are observed, while the reverse is true if negative outcomes are witnessed. In the present study, however, this correlation was observed only partially: Exposure to models eating broccoli while conveying negative facial expressions resulted in a greater reduction in liking ratings, whereas the reverse did not hold. Watching others eating a raw vegetable with a positive facial expression did not increase adults' vegetable liking or eating desire.

One possible explanation may be that avoiding any food—irrespective of whether it is commonly liked or disliked—that appears disgusting can protect us from eating something that tastes bad or is harmful. Another reason may be that smiling while eating is perceived as an untypical display of liking a certain food.

"This might imply that watching someone eating a raw vegetable with positive facial expressions does not seem an effective strategy for increasing adults' vegetable consumption.

Part 1

Comment by Dr. Krishna Kumari Challa on January 12, 2024 at 9:57am

In a new paper, scientists describe a new peptide that binds directly to MYC with what is called sub-micro-molar affinity, which is getting closer to the strength of an antibody. In other words, it is a very strong and specific interaction.

Researchers now improved the binding performance of this peptide over previous versions by two orders of magnitude. This makes it closer to their drug development goals.

Currently, the researchers are using lipid nanoparticles to deliver the peptide into cells. These are small spheres made of fatty molecules, and they are not ideal for use as a drug. Going forward, the researchers are developing chemistry that improves the lead peptide's ability to get inside cells.

Once the peptide is in the cell, it will bind to MYC, changing MYC's physical properties and preventing it from performing transcription activities.

MYC represents chaos, basically, because it lacks structure. That, and its direct impact on so many types of cancer make it one of the holy grails of cancer drug development.

Zhonghan Li et al, MYC-Targeting Inhibitors Generated from a Stereodiversified Bicyclic Peptide Library, Journal of the American Chemical Society (2024). DOI: 10.1021/jacs.3c09615

Part 2

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