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Comment by Dr. Krishna Kumari Challa on August 25, 2021 at 10:10am

A host  enzyme allows viruses to ride roughshod in the liver, paving the way to cancer

Chronic viral infections in the liver can lead to organ dysfunction and ultimately to liver tumors in a progression invariably characterized by viruses that proliferate free of immune system restraints.

Although it has been known for decades that chronic viral infection of the liver can lead to cancer, medical investigators have only now begun to fully appreciate how the disruption of molecular signaling sets the stage for virus-induced liver cancer.

In an elegant series of cellular studies, scientists have found that a transmembrane enzyme (a protein embedded in the cell with active portions above and below the cell surface) plays a powerful role in damaging liver cells.

That enzyme goes by the name of hepsin, and is produced by the host. It increases vulnerability to liver cancer because it's a noteworthy turncoat—a biological traitor—when active in the milieu of a viral infection. Although the research team saw the damaging activity in the lab when two types of viruses, Sendai and herpes, were studied, the major global health crisis involving liver infections and cancer are centered squarely on hepatitis B and C.

Hepsin, as it turns out, doesn't even mess with the viruses themselves to create havoc in the liver; it irrevocably damages a protective protein called STING. Once STING is crippled, viruses are free to run roughshod through the liver.

Fu Hsin et al, The transmembrane serine protease hepsin suppresses type I interferon induction by cleaving STING, Science Signaling (2021). DOI: 10.1126/scisignal.abb4752

https://medicalxpress.com/news/2021-08-turncoat-protein-viruses-rou...

Comment by Dr. Krishna Kumari Challa on August 24, 2021 at 12:15pm

Some Rare Diamonds Form Out of The Remains of Once-Living Creatures

New research has discovered that two different types of rare diamonds share a common origin story – the recycling of once-living organisms over 400 kilometers (250 miles) below the surface.

There are three main types of natural diamonds. The first are lithospheric diamonds, which form in the lithospheric layer around 150 to 250 kilometers (93 - 155 miles) below the surface of Earth. These are by far the most common.

Then there are two rarer types - oceanic and super-deep continental diamonds.

Oceanic diamonds are found in oceanic rocks, while deep continental diamonds are those formed between 300 and 1,000 kilometers (186 and 621 miles) below the surface of Earth.

 oceanic and super-deep continental diamonds seem pretty different. Because variation in a carbon isotope signature called δ¹³C (delta carbon thirteen) can be used to determine whether the carbon has an organic or inorganic origin, past researchers have suggested that oceanic diamonds originally formed from organic carbon that was once within living beings.

Super-deep continental diamonds, on the other hand, have an extremely variable amount of δ¹³C. It's hard to tell whether they're made of organic carbon or not.

But in this new paper, led by Curtin University geologist Luc Doucet, the team found that the cores of super-deep continental diamonds have a similar δ¹³C composition. Surprisingly, this means that, like oceanic diamonds, these gems also contain the remains of once-living creatures.

https://www.nature.com/articles/s41598-021-96286-8

https://www.sciencealert.com/rare-diamonds-are-actually-made-of-onc...

Comment by Dr. Krishna Kumari Challa on August 24, 2021 at 11:04am

Some researchers have proposed that the brain does not measure the time we have spent awake – rather, it tracks how hard the brain works while we’re awake, and adjusts the amount of sleep we need accordingly. Research in support of this theory has found that individual areas of cortex can briefly switch off when overworked, even while the rest of the brain is still awake. This temporary shutdown of individual brain areas is termed “local sleep” and thought to be a mechanism that allows the brain’s cells to recover. While a person might not notice it, such a localised shutdown can profoundly affect someone’s performance – for example while driving a car.

But our brain would be very inefficient if individual parts of the cortex often went into local sleep whenever they felt they needed to. This is why it’s thought that the cortex may not only generate local sleep, but also activate the main sleep centres.

. Suppressing sleep might be dangerous, as sleep serves several essential, but still poorly understood, functions in our body and brain – such as memory processing, and making sure our immune system and metabolism function properly. But for many of us who struggle to feel tired and fall asleep, manipulating the cortex could become a way of triggering sleep when we’re struggling to nod off.

https://theconversation.com/feeling-tired-heres-how-the-brains-inte...

part 2

Comment by Dr. Krishna Kumari Challa on August 24, 2021 at 11:00am

How the brain’s internal ‘hourglass’ controls our need for sleep 

Although sleep is absolutely vital, until now it hasn’t been known which structure of the brain tells us when we are tired. But  a  recent study has shown in laboratory mice that the cerebral cortex, which is responsible for the most complex brain functions – including perception, language, thought and episodic memory – helps us track our need for sleep.

To ensure that we get enough sleep, our brain uses two tools: a clock and an hourglass. Our biological clock helps us to keep a 24-hour rhythm. It’s controlled by the suprachiasmatic nucleus, which is a small area deep in our brain. This coordinates the rhythms of various organs, and helps us to sleep at night and wake up in the morning.

But our biological clock is only a guide – it’s not the main regulator of sleep. Instead, the brain uses an “hourglass” to keep track of the accumulated amount of sleep we’ve had. This hourglass slowly empties while we’re awake and refills while we’re asleep. This is why we’re able to stay awake longer when we need to, and make up this sleep deficit later by napping or sleeping longer the next night.

part 1

Comment by Dr. Krishna Kumari Challa on August 24, 2021 at 10:43am

First video evidence of tortoises hunting birds / Curr. Biol., Aug. 23, 2021 (Vol. 31, Issue 16)

Comment by Dr. Krishna Kumari Challa on August 24, 2021 at 10:39am

Study: Benefits outweigh risks for autonomous vehicles—as long as you regulate them

An interdisciplinary panel of experts has assessed the risks and potential benefits associated with deploying autonomous vehicles (AVs) on U.S. roads and predicts that the benefits will substantially outweigh potential harms—but only if the AVs are well regulated.

Veljko Dubljevic et al, Toward a rational and ethical sociotechnical system of autonomous vehicles: A novel application of multi-criteria decision analysis, PLOS ONE (2021). DOI: 10.1371/journal.pone.0256224

https://techxplore.com/news/2021-08-benefits-outweigh-autonomous-ve...

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Comment by Dr. Krishna Kumari Challa on August 24, 2021 at 10:35am

One material with two functions could lead to faster memory

In a step toward a future of higher performance memory devices, researchers  have developed a new device that needs only a single semiconductor known as perovskite to simultaneously store and visually transmit data.

By integrating a light-emitting electrochemical cell with a resistive random-access memory that are both based on perovskite, the team achieved parallel and synchronous reading of data both electrically and optically in a 'light-emitting memory.'

Meng-Cheng Yen et al, All-inorganic perovskite quantum dot light-emitting memories, Nature Communications (2021). DOI: 10.1038/s41467-021-24762-w

https://techxplore.com/news/2021-08-material-functions-faster-memor...

Comment by Dr. Krishna Kumari Challa on August 24, 2021 at 10:17am

High-efficiency ultraviolet light emitting diodes to sterilize pathogens, including SARS -CoV-2

Every year, thousands of lives and billions of dollars are spent worldwide as a result of health-care associated and waterborne illnesses. Sterilization is a critical preventative measure and it can be achieved by a number of techniques including irradiation using ultraviolet (UV) light. This need has gained greater urgency because of the global coronavirus pandemic, as effective sterilization practices can curtail the spread of infectious diseases.

Current sources like mercury lamps are bulky, contain toxic chemicals and are not as versatile in applications as semiconductor light sources. AlGaN is the material of choice for high efficiency deep UV light sources, which is the only alternative technology to replace mercury lamps for water purification and disinfection. To date, however, AlGaN-based mid and deep UV LEDs exhibit very low efficiency. One of the primary limiting factors is the poor hole injection, due to the ineffective p-type doping of AlGaN alloys using Mg, especially for the high Al composition alloys that are essential for the UV-C (200-280 nm) wavelength ranges.

A promising technique that can overcome this challenge and enhance hole injection into the device active region is by utilizing a tunnel junction structure. The hole injection in such devices is driven by the interband transport of electrons from the valence band of the p-type layer to the conduction band of the n-type layer.

A. Pandey et al, High-efficiency AlGaN/GaN/AlGaN tunnel junction ultraviolet light-emitting diodes, Photonics Research (2020). DOI: 10.1364/PRJ.383652

A. Pandey et al, High-efficiency AlGaN/GaN/AlGaN tunnel junction ultraviolet light-emitting diodes, Photonics Research (2020). DOI: 10.1364/PRJ.383652

https://phys.org/news/2021-08-high-efficiency-ultraviolet-emitting-...

Comment by Dr. Krishna Kumari Challa on August 24, 2021 at 10:06am

The analysis of regular flavonoid intake with gut microbiome and blood pressure levels found:

• Study participants who had the highest intake of flavonoid-rich foods, including berries, red wine, apples and pears, had lower systolic blood pressure levels, as well as greater diversity in their gut microbiome than the participants who consumed the lowest levels of flavonoid-rich foods.
• Up to 15.2% of the association between flavonoid-rich foods and systolic blood pressure could be explained by the diversity found in participants' gut microbiome.
• Eating 1.6 servings of berries per day (one serving equals 80 grams, or 1 cup) was associated with an average reduction in systolic blood pressure levels of 4.1 mm Hg, and about 12% of the association was explained by gut microbiome factors.

• Drinking 2.8 glasses (125 ml of wine per glass) of red wine a week was associated with an average of 3.7 mm Hg lower systolic blood pressure level, of which 15% could be explained by the gut microbiome.

https://medicalxpress.com/news/2021-08-gut-bacteria-flavonoid-rich-...

part 2

Comment by Dr. Krishna Kumari Challa on August 24, 2021 at 10:05am

Gut bacteria and flavonoid-rich foods are linked and improve blood pressure levels

Flavonoid-rich foods, including berries, apples, pears and wine, appear to have a positive effect on blood pressure levels, an association that is partially explained by characteristics of the gut microbiome, according to new research published today in Hypertension, an American Heart Association journal.

Our gut microbiome plays a key role in metabolizing flavonoids to enhance their cardioprotective effects, and this study provides evidence to suggest these blood pressure-lowering effects are achievable with simple changes to the daily diet.

Flavonoids are compounds found naturally in fruits, vegetables and plant-based foods such as tea, chocolate and wine, and have been shown in previous research to offer a variety of health benefits to the body. Flavonoids are broken down by the body's gut microbiome—the bacteria found in the digestive tract. Recent studies found a link between gut microbiota, the microorganisms in the human digestive tract, and cardiovascular disease (CVD), which is the leading cause of death worldwide. Gut microbiota is highly variable between individuals, and there are reported differences in gut microbial compositions among people with and without CVD.

With increased research suggesting flavonoids may reduce heart disease risk, this study assessed the role of the gut microbiome on the process. Researchers examined the association between eating flavonoid-rich foods with blood pressure and gut microbiome diversity. The study also investigated how much variance within the gut microbiome could explain the association between intake of flavonoid-rich foods and blood pressure.

Microbial Diversity and Abundance of Parabacteroides Mediate the Associations Between Higher Intake of Flavonoid-Rich Foods and Lower Blood Pressure, Hypertension (2021). www.ahajournals.org/doi/10.116 … TENSIONAHA.121.17441

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