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Comment by Dr. Krishna Kumari Challa on September 7, 2022 at 9:02am

Researchers capture live footage of virus infecting cell

In a first, scientists have captured on video all the steps a virus follows as it enters and infects a living cell in real time and in three dimensions.

Scientists achieved the feat by using advanced imaging called lattice light sheet microscopy as well as chemical and genetic manipulation.

The first part of the video shown here follows a virus engineered to sprout SARS-CoV-2 spike proteins (labeled pink) as it is captured at a cell surface and engulfed by a cellular compartment called an endosome. The virus then fuses with the endosome membrane and injects its genetic material (labeled blue) inside the cell—the steps necessary to kick off a cycle of viral infection and replication.

The second part of the video shows many such viruses inside the cell. The video covers 4 minutes of activity, with snapshots taken every 4 seconds.

The findings, published Sept. 1 in PNAS, provide new insights into the fundamental mechanics of viral infection and could point the way to new methods for intervening before the onset of COVID-19.

The researchers' work reveals that viruses can't fuse with the membrane and release their genomes unless they're bathed in a slightly acidic environment. Experiments indicated that the pH must fall between 6.2 and 6.8, just shy of neutral and on par with bodily fluids such as saliva and urine. Endosomes have such acidity, and the team's measurements confirmed that this is also the pH range inside a typical human nose, where SARS-CoV-2 infection often begins.

https://hms.harvard.edu/news/breaking-entering

Comment by Dr. Krishna Kumari Challa on September 6, 2022 at 8:51am

Breakthrough in addressing glioblastoma, a deadly brain cancer

Comment by Dr. Krishna Kumari Challa on September 6, 2022 at 8:23am

Training astronauts to be scientists on the moon

Astronauts with their sights on the moon are receiving world-class geology training during the fifth edition of ESA's Pangaea campaign. From choosing landing sites for a future Artemis mission, to designing science operations for the lunar surface, the course challenges space explorers to become field scientists.

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It's raining diamonds across the universe, research suggests It could be raining diamonds on planets throughout the universe, scientists suggested Friday, after using common plastic to recreate the strange precipitation believed to form deep inside Uranus and Neptune. -- Soil temperature can predict pest spread in crops A new study from North Carolina State University shows soil temperature can be used to effectively monitor and predict the spread of the corn earworm (Helicoverpa zea), a pest that ravages corn, cotton, soybeans, peppers, tomatoes and other vegetable crops. The ability to better monitor the pest and make predictions about where it will appear could help farmers control the pest more effectively, which would reduce the financial and environmental impacts of pesticide use. -- Bees use patterns, not just colors, to find flowers Honeybees rely heavily on flower patterns—not just colors—when searching for food, new research shows.

Comment by Dr. Krishna Kumari Challa on September 6, 2022 at 8:22am

New polar ring galaxy discovered

Astronomers report the detection of a new polar ring galaxy using the data obtained with the Subaru Telescope as part of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP). 

The so-called polar ring galaxies (PRGs) are systems composed of an S0-like galaxy and a polar ring, which remain separate for billions of years. In general, these outer polar rings, composed of gas and stars, are aligned roughly in a perpendicular orientation with respect to the major axis of the central host galaxy.

However, although more than 400 PRG candidates have been discovered to date, only dozens of them have been confirmed as real polar ring galaxies by follow-up spectroscopic observations.

Minoru Nishimura, Kazuya Matsubayashi, Takashi Murayama, Yoshiaki Taniguchi, A New Polar Ring Galaxy Discovered in the COSMOS Field. arXiv:2208.12388v1 [astro-ph.GA], arxiv.org/abs/2208.12388

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Comment by Dr. Krishna Kumari Challa on September 6, 2022 at 6:34am

The physics of walking: For multi-legged creatures, it's a lot like slithering

Comment by Dr. Krishna Kumari Challa on September 5, 2022 at 11:50am

Your blood type could predict your risk of having a stroke before age 60, new study suggests

A person's blood type may be linked to their risk of having an early stroke, according to a new meta-analysis done by researchers. Findings were published today in the journal Neurology. The meta-analysis included all available data from genetic studies focusing on ischemic strokes, which are caused by a blockage of blood flow to the brain, occurring in younger adults under age 60.

The number of people with early strokes is rising. These people are more likely to die from the life-threatening event, and survivors potentially face decades with disability. Despite this, there is little research on the causes of early strokes.

Researchers conducted the study by performing a meta-analysis of 48 studies on genetics and ischemic stroke that included 17,000 stroke patients and nearly 600,000 healthy controls who never had experienced a stroke. They then looked across all collected chromosomes to identify genetic variants associated with a stroke and found a link between early-onset stroke—occurring before age 60—and the area of the chromosome that includes the gene that determines whether a blood type is A, AB, B, or O.

The study found that people with early stroke were more likely to have blood type A and less likely to have blood type O (the most common blood type)—compared to people with late stroke and people who never had a stroke. Both early and late stroke were also more likely to have blood type B compared to controls. After adjusting for sex and other factors, researchers found those who had blood type A had an 16 percent higher risk of having an early stroke than people with other blood types. Those who had blood type O had a 12 percent lower risk of having a stroke than people with other blood types.

The researchers emphasized that the increased risk was very modest and that those with type A blood should not worry about having an early-onset stroke or engage in extra screening or medical testing based on this finding.

Genetic Contributions to Early and Late Onset Ischemic Stroke, Neurology (2022). dx.doi.org/10.1212/WNL.0000000000201006

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Comment by Dr. Krishna Kumari Challa on September 4, 2022 at 12:09pm

Study finds enzyme in the brain is a 'metastat' for body weight

An enzyme found in the brain acts as a major regulator of body weight,  researchers have discovered. In a new study, they found that removing the enzyme from neurons in a part of the brain known as the hypothalamus led mice to gain weight and burn less fat. This finding, they say, suggests that the enzyme could be a target for treating metabolic disease.

The findings were published Aug. 31 in Science Advances.

Dysregulated metabolism is implicated in a host of metabolic disorders, including obesity and diabetes. The hypothalamus region of the brain is essential for metabolic control and the area known as the ventromedial hypothalamus is known to regulate body weight, eating, and glucose balance. How the ventromedial hypothalamus does this, however, is less clear.

For the study,  researchers focused on an enzyme called O-linked b-D-N-acetylglucosamine transferase, or OGT. Though researchers have a partial understanding of the enzyme’s role in other parts of the body — such as mediating nutritional and hormonal regulation in different organs and tissues — what it does in the brain is largely unknown.

As a first step, researchers observed what happened to OGT in neurons of the ventromedial hypothalamus when food intake was adjusted. They found that when mice consumed less food, OGT levels went up.

This suggested that OGT plays an important role as a nutrient sensor in this neuron population.

To better understand this role, researchers bred mice that lacked OGT in neurons of the ventromedial hypothalamus. They found that the mice gained weight very quickly on a normal diet, becoming much heavier than typical mice even though they were eating the same amount of food and were just as physically active.

A key difference was that the mice without OGT expended less energy than their counterparts.

Just sitting at rest, you burn energy because you need to maintain the vital functions of the body, such as breathing, digestion, and brain activity. And though the mice lacking OGT weren’t less physically active, they burned less energy at this basal level.

They also responded differently to fasting. When the body has adequate amounts of food, its preferred fuel is glucose. But when you fast, your glucose runs out quickly. The body then taps into its fat stores in order to meet energy demands.

But in the study, mice lacking OGT didn’t burn fat as much as other mice when food was restricted.

The problem had to do with glucose-sensing, said the researchers. The ability to sense glucose is essential for keeping it at the level the body needs. If neurons can’t sense glucose properly, they won’t make necessary metabolic adjustments, such as telling the body to burn fat. In the study, neurons without OGT didn’t sense glucose as well as those with the enzyme.

Without OGT, the body can’t sense that less food is coming in, and then it doesn’t tell its fat tissues to burn fat. Researchers liken OGT to a thermostat, or a “metastat,”  since OGT is crucial for metabolic homeostasis.


And that set point will be different from individual to individual.

Because of this, OGT could be a target for treating metabolic diseases. It’s possible that, in the future, a drug could be used to target OGT in ventromedial hypothalamus neurons to fine-tune a person’s body weight set point, adjusting it if it’s too high or too low.

One day we might be able to reprogram a person’s metastat to achieve desired body weight, the researchers think.

https://news.yale.edu/2022/08/31/study-finds-enzyme-brain-metastat-...

Comment by Dr. Krishna Kumari Challa on September 3, 2022 at 11:26am

Researcher unlocks mystery of 'chemo-brain,' identifies possible treatment

Though chemotherapy can be lifesaving, the cancer treatment often leaves patients suffering from debilitating side effects, including cognitive impairments in processing speed, memory, executive function and attention. Dubbed "chemo brain," these lingering symptoms can dramatically impact patients' quality of life long after they have completed their cancer treatments.

This is the first evidence that chemotherapy alters an important cellular pathway called sphingolipid metabolism in critical areas of the brain linked to cognitive function.

Currently, there are no FDA-approved drugs to mitigate these deficits. In breakthrough findings, researchers have uncovered some of the molecular events that happen when chemotherapy drugs cause these deficits. More promising still, they've found that an already-approved FDA drug designed to treat multiple sclerosis also appears to work to reduce chemotherapy-related cognitive impairment (CRCI).

 Silvia Squillace et al, Sphingosine-1-phosphate receptor 1 activation in the central nervous system drives cisplatin-induced cognitive impairment, Journal of Clinical Investigation (2022). DOI: 10.1172/JCI157738

Comment by Dr. Krishna Kumari Challa on September 3, 2022 at 10:56am

Circadian rhythm disruption found to be common among mental health disorders

Anxiety, autism, schizophrenia and Tourette syndrome each have their own distinguishing characteristics, but one factor bridging these and most other mental disorders is circadian rhythm disruption, according to a team of neuroscience, pharmaceutical sciences and computer science researchers .

In an article published recently in the Nature journal Translational Psychiatry, the scientists hypothesize that CRD is a psychopathology factor shared by a broad range of mental illnesses and that research into its molecular foundation could be key to unlocking better therapies and treatments.

Circadian rhythms regulate our bodies' physiological activity and biological processes during each solar day. Synchronized to a 24-hour light/dark cycle, circadian rhythms influence when we normally need to sleep and when we're awake. They also manage other functions such as hormone production and release, body temperature maintenance and consolidation of memories. Effective, nondisrupted operation of this natural timekeeping system is necessary for the survival of all living organisms.

Circadian rhythms are intrinsically sensitive to light/dark cues, so they can be easily disrupted by light exposure at night, and the level of disruption appears to be sex-dependent and changes with age. One example is a hormonal response to CRD felt by pregnant women; both the mother and the fetus can experience clinical effects from CRD and chronic stress.

Circadian rhythms play a fundamental role in all biological systems at all scales, from molecules to populations. This new work analysis found that circadian rhythm disruption is a factor that broadly overlaps the entire spectrum of mental health disorders.

The telltale sign of circadian rhythm disruption—a problem with sleep—was present in each disorder.While  the focus was on widely known conditions including autism, ADHD and bipolar disorder, researchers argue that the CRD psychopathology factor hypothesis can be generalized to other mental health issues, such as obsessive-compulsive disorder, anorexia nervosa, bulimia nervosa, food addiction and Parkinson's disease. The researchers found ample evidence of the connection by thoroughly examining peer-reviewed literature on the most prevalent mental health disorders.

Amal Alachkar et al, The hidden link between circadian entropy and mental health disorders, Translational Psychiatry (2022). DOI: 10.1038/s41398-022-02028-3

Comment by Dr. Krishna Kumari Challa on September 2, 2022 at 11:23am

Carbon dioxide should cost 3.6 times more than US price, study says

Each ton of carbon dioxide that exits a smokestack or tailpipe is doing far more damage than what governments take into account, researchers conclude in a scientific paper published recently. 

Major hurricanes pack more rain, while extremes of wildfire, drought and downpours are all happening more often and with more intensity due to climate change, causing loss of communities, homes and lives all over the world. But what is the actual cost in dollar terms of the carbon emissions driving climactic change?

That's what researchers from a variety of fields—science, economics, medicine—are trying to figure out through a metric called the social cost of carbon, a price that represents the total climate damage caused to society through carbon emissions. It's been used in the past to justify tougher limits on carbon emissions and more spending on climate solutions, like transitioning to renewable energy and natural flood protection.

Currently, the United States government uses a price of $51 per ton of carbon dioxide emitted, but the researchers wrote in the journal Nature that the price should be $185 per ton—3.6 times higher than the current U.S. standard.

David Anthoff, Comprehensive Evidence Implies a Higher Social Cost of CO₂, Nature (2022). DOI: 10.1038/s41586-022-05224-9. www.nature.com/articles/s41586-022-05224-9

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Europe's fiery summer: a climate 'reality check'? Wildfires and storms. Rivers at record lows. Parched crops withering in the fields. For many Europeans, this year's scorching summer means climate change is increasingly hard to ignore.

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