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Comment by Dr. Krishna Kumari Challa on August 5, 2023 at 10:18am

Consuming added sugars may increase risk of kidney stones

Between 7% and 15% of people in North America, between 5% and 9% of people in Europe, and between 1% and 5% of people in Asia suffer from kidney stones. Common symptoms are severe pain, nausea, vomiting, fever, chills, and bloody urine. But kidney stones don't just reduce the quality of life; in the long run, they may lead to infections, swollen kidneys (hydronephrosis), renal insufficiency, and end-stage renal disease. Known risk factors for developing kidney stones include being an adult male, obesity, chronic diarrhea, dehydration, and having inflammatory bowel disease, diabetes, or gout.

Now, a study in Frontiers in Nutrition has shown for the first time that an elevated consumption of added sugars should probably be added to the list of 

risk factors for kidney stones. Added sugars occur in many processed foods, but are especially abundant in sugar-sweetened sodas, fruit drinks, candy, ice cream, cakes, and cookies. It suggests that limiting added sugar intake may help to prevent the formation of kidney stones.

Researchers analyzed epidemiological data on 28,303 adult women and men, collected between 2007 to 2018 within the US National Health and Nutrition Examination Survey (NHANES). Participants self-reported if they had a history of kidney stones. Each participant's daily intake of added sugars was estimated from their recall of their most recent consumption of food and drinks, given twice: once in a face-to-face interview, and once in a telephone interview between three and 10 days later. For example, participants were asked if they had eaten syrups, honey, dextrose, fructose, or pure sugar during the past 24 hours.

Each participants also received a healthy eating index score (HEI-2015), which summarized their diet in terms of the adequacy of beneficial diet components such as fruits, vegetables, and whole grains, and moderation of potentially harmful foods, for example refined grains, sodium, and saturated fats.

The researchers adjusted the odds of developing kidney stones per year during the trial for a range of explanatory factors. These included gender, age, race or ethnicity, relative income, BMI, HEI-2015 score, smoking status, and whether the participants had a history of diabetes.

The researchers showed that after adjusting for these factors, the percentage of energy intake from added sugars was positively and consistently correlated with kidney stones. For example, participants whose intake of added sugars was among the 25% highest in the population had 39% greater odds of developing kidney stones over the course of the study.

Similarly, participants who derived more than 25% of their total energy from added sugars had a 88% greater odds than those who derived less than 5% of their total energy from added sugars.

The results also indicated that participants from "other" ethnicities—for example Native American or Asian people—had higher odds of developing kidney stones when exposed to greater-than-average amounts of added sugars than Mexican American, other Hispanic, non-Hispanic white, and non-Hispanic Black people. People with a greater poverty-income ratio (PIR; i.e., the ratio between their income and the federal poverty level) had greater odds of developing kidney stones when exposed to more added sugars than people at or slightly above poverty level.

Part 1

Comment by Dr. Krishna Kumari Challa on August 5, 2023 at 9:52am

Researchers analyzed the participants' brain activity throughout the whole brain and investigated whether different brain areas work together in a distinct way compared to the baseline scan.

Their findings showed that even though psilocybin, LSD, meditation and hypnosis induce overlapping subjective effects, the underlying brain changes are distinct.

The findings gathered by this team of researchers suggest that while some might report having similar experiences or feelings under these different states of consciousness, what is happening in their brain is actually very different. While psilocybin and LSD appeared to produce similar brain activity, the changes they induced were markedly different from those observed during meditation or hypnosis. This suggests that psychedelics, meditation and hypnosis have distinct underlying mechanisms of action and overall different effects on the brain.

Overall, these results suggest that these three distinct states may have synergistic therapeutic effects and may not therapeutically substitute each other. In the future, they could pave the way for further investigations of their unique strengths and benefits, potentially informing the development of new promising therapeutic strategies for psychiatric disorders.

Flora F. Moujaes et al, Comparing neural correlates of consciousness: from psychedelics to hypnosis and meditation, Biological Psychiatry: Cognitive Neuroscience and Neuroimaging (2023). DOI: 10.1016/j.bpsc.2023.07.003

Part 2

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Comment by Dr. Krishna Kumari Challa on August 5, 2023 at 9:50am

Exploring what happens in the brain under the influence of psychedelics, while meditating and during hypnosis

Changes in a person's "normal" mental state after taking drugs, while meditating, during hypnosis or due to specific medical conditions have been a topic of study for several years now. Some of these mental changes, which are known as altered states of consciousness, have been found by some to have potentially beneficial effects, reducing stress and fostering greater well-being.

Researchers have recently been exploring the potential of psychedelic drugs, such as psilocybin and lysergic acid diethylamide (LSD) for treating depression and other mental disorders. In a recent paper published in Biological Psychiatry: Cognitive Neuroscience and Neuroimaging, they compared the brains of people who had taken psychedelics to those of others who were meditating or were hypnotized. 

Anecdotally, people often report similarities in experiences induced by hypnosis, meditation, or psychedelics. However, our neurobiological understanding of these states is only just evolving.

While many studies looked at individual altered states of consciousness and how they manifest in the brain, comparisons between these states remain scarce. This study tried to bridge that gap. 

Rather than conducting a single experiment that collectively involved psychedelics, meditation and hypnosis, the researchers analyzed datasets conducted during four distinct experimental trials. The first two trials examined the effects of two different psychedelic drugs on the brain, namely psilocybin and LSD, while the last two focused on hypnosis and meditation.

For the psychedelic studies, they included healthy participants who subsequently received psilocybin, LSD, or a placebo, whereas the meditation and hypnosis studies were conducted with participants who were experts in the respective field to make sure they can reach the state in an MR environment.

During the team's four experimental trials, all participants were asked to simply lay inside an MRI scanner without completing any task or engaging in any activity. The MRI scanner recorded their brain activity both while they were in a normal state of consciousness and under the altered state of consciousness relevant to that trial (i.e., after taking psychedelics, while meditating or while under hypnosis).

Part 1

Comment by Dr. Krishna Kumari Challa on August 4, 2023 at 12:02pm

The Bioconcrete Revolution

Concrete is the most important building material on Earth – and it’s also responsible for a MASSIVE chunk of global carbon emissions. Join George as he discovers how a surprising discovery in 1973 could dramatically change how we make concrete forever.

Comment by Dr. Krishna Kumari Challa on August 4, 2023 at 11:08am

Tree rings reveal that it has not been this warm in the past 1,200 years

A new 1,200 year-long time series based on tree rings shows that the current warming is unprecedented during this period. This is reported by researchers  in the scientific journal Nature.

The Middle Ages and the centuries that followed were not only turbulent socially, but also climatically. Not only was there a "Little Ice Age," but also its opposite: the "Medieval climate anomaly," during which it may have been unusually warm. The latter can clearly be seen in reconstructed temperatures from annual tree rings. In fact, reconstructed Medieval temperatures are often portrayed as higher than today's temperatures.

The previous reconstructions based on tree ring density, in contrast, indicated significantly higher temperatures for the Medieval climate anomaly and lower temperatures for the current warming. "This is critical because such reconstructions are considered when evaluating the accuracy of climate models. If the previous reconstructions were used as a benchmark, this would significantly downplay the human influence on current  climate warming and reduce confidence in model projections.

This has long been a puzzle because there is no known physical explanation for such exceptional Medieval warmth. Climate models are therefore unable to simulate it and instead show only moderately warm temperatures for the Medieval climate anomaly.

Previous reconstructions are based on the width or density of the annual tree rings. Both are very much dependent on temperature, but sometimes other factors play a role in how wide or dense a tree ring gets.

For their study researchers now  used a new method optimized at WSL to directly measure the cell wall thickness of the wood cells in the annual tree rings. Each individual cell in each tree ring records climatic information under which it was formed. By analyzing hundreds, sometimes thousands of cells per ring, extraordinary pure climate information can be obtained.

For their new time series, the researchers measured the cell walls of 50 million cells. These come from 188 living and dead Swedish and Finnish Scots pines (Pinus sylvestris), whose annual rings together cover a period of 1,170 years. Based on these measurements, the researchers then reconstructed the summer temperatures in this region and compared them both with model simulations of the regional climate and with previous reconstructions based on the density of the annual rings.

Researchers have created a new reconstruction based on a particularly precise method to extract temperature information from trees. In contrast to previous work, the new results lead to the same conclusion as the climate models: the Medieval climate anomaly was cooler than previously thought, at least in Scandinavia, where the wood studied originated. Today's warming is thus likely outside the range of natural fluctuations in temperatures over the past 1,200 years, the researchers conclude.

Jesper Björklund et al, Fennoscandian tree-ring anatomy shows a warmer modern than medieval climate, Nature (2023). DOI: 10.1038/s41586-023-06176-4

Comment by Dr. Krishna Kumari Challa on August 4, 2023 at 10:12am

Geostationary satellite reveals widespread midday depression in dryland photosynthesis during 2020 heat wave

We are facing unprecedented heat waves . These conditions have resulted in severe consequences for both human and nature systems, including dire water shortages, rampant wildfires, substantial agricultural losses, and increased human mortality.

The places where these heat waves occur, ecosystems face exacerbated water stress due to more frequent and protracted droughts and heat waves, which can profoundly impair ecosystem photosynthesis and carbon uptake, in turn affecting the global carbon cycle.

Investigating vegetation photosynthesis at various time scales provides valuable insights into vegetation growth, carbon uptake, and environmental interactions. Traditional polar-orbiting satellite observations have aided in monitoring gross primary production (GPP) at longer scales (e.g., monthly, annual), but they are limited in capturing diurnal variations. Fortunately, in recent years, emerging new-generation geostationary satellites with sub-daily sampling capability, provide unique opportunities to study diurnal variations of vegetation photosynthesis and their responses to environmental conditions over the course of day at large spatial scales.

In a recent study, scientists estimated hourly GPP across the Conterminous U.S. based on observations from Geostationary Operational Environmental Satellite-R (GOES-R), and then investigated how the diurnal cycle of photosynthesis responded to the severe late-summer heat wave of 2020. The work is published in the journal Science Advances.

The study provides an exploration of heat wave impacts on the diurnal dynamics of photosynthesis at a continental scale, revealing a widespread midday and afternoon depression of photosynthesis in dryland ecosystems during the heat wave. In the study the researchers examine the environmental regulation of diurnal photosynthesis dynamics across diverse ecosystems, and illustrate how current radiation-based methods for upscaling polar-orbiting satellite snapshots to daily means may under- or overestimate daily GPP.

They found a widespread midday and afternoon depression in ecosystem photosynthesis during the heat wave .

The diurnal metrics exhibit divergent responses to the heat wave across vegetation types and along aridity gradients. Overall, shrubland and grassland are more sensitive to the heat wave than the other vegetation types.

The impact of the heat wave on the diurnal cycle of photosynthesis is predominantly observed in arid and semiarid regions with an aridity index (AI) below 0.6. They found that the largest GPP loss occurred at noon or during the afternoon for the majority of western regions, later than the GPP peak hour during the heat wave year, further substantiating the asymmetric influence of heat waves on diurnal photosynthesis fluctuations.

 Xing Li et al, New-generation geostationary satellite reveals widespread midday depression in dryland photosynthesis during 2020 western U.S. heatwave, Science Advances (2023). DOI: 10.1126/sciadv.adi0775

Comment by Dr. Krishna Kumari Challa on August 4, 2023 at 9:31am

Study shows people experience emotions with computer-generated art

Computers and artificial intelligence (AI) are becoming increasingly important in the art world. AI-generated artworks fetch millions at auction, and artists routinely use algorithms to create aesthetic content.

Now, a team of researchers  has conducted experiments showing that, contrary to popular intuition, people perceive emotions and intentions when viewing art, even when they know the work was generated by a computer. The study was published in the journal Computer in Human Behavior.

Jason Allen’s A.I.-generated work, “Théâtre D’opéra Spatial,” ( Source: nytimes)

Researchers investigated whether people respond emotionally to, or perceive intentionality in, art that they believe was generated by a computer.

The researchers presented participants with abstract black-and-white artworks, explaining that the artworks were either randomly generated by a computer or intentionally created by a person to evoke emotion.

Before viewing each artwork, participants were told whether it was supposedly created by a computer or a person; this information was true in half of the cases. The participants were then asked to rate the artworks based on several dimensions. In addition, they were asked to indicate the emotions they personally experienced while viewing the artworks, the emotions they believed the artworks were intended to evoke in viewers, and the emotions, if any, they believed the artists themselves felt while creating the artworks.

The results showed that participants almost always experienced some emotion and perceived some level of intentionality.

The study thereby provides new empirical evidence that people can form emotional attachments to computer-generated art. So contrary to common assumptions, people seem to perceive emotions and intentions even when they know that something was created by a computer. However, they reported stronger emotions and rated the artwork more positively if it had actually been created by a person—even when they got the wrong information that the art was computer-generated.

Thus, the results also show that a subtle but significant difference in emotional impact remains between human and artificial art. This could point to specific characteristics in man-made art that are perceived by viewers.

Overall, the results raise new questions for human-computer interaction and the growing role of AI as a creative entity in art, design, and entertainment.

 Theresa Rahel Demmer et al, Does an emotional connection to art really require a human artist? Emotion and intentionality responses to AI- versus human-created art and impact on aesthetic experience., Computers in Human Behavior (2023). DOI: 10.1016/j.chb.2023.107875

Comment by Dr. Krishna Kumari Challa on August 4, 2023 at 9:22am

Study reveals unexpected importance of the thymus in adults

The thymus gland—which produces immune T cells before birth and during childhood— is often regarded as nonfunctional in adults, and it's sometimes removed during cardiac surgery for easier access to the heart and major blood vessels.

New research  by investigators and  published in the New England Journal of Medicine has uncovered evidence that the thymus is in fact critical for adult health generally and for preventing cancer and perhaps autoimmune disease.

To determine whether the thymus provides health benefits to adults, the team evaluated the risk of death, cancer, and autoimmune disease among 1,146 adults who had their thymus removed during surgery and among 1,146 demographically matched patients who underwent similar cardiothoracic surgery without thymectomy. The scientists also measured T cell production and blood levels of immune-related molecules in a subgroup of patients.

Five years after surgery, 8.1% of patients who had a thymectomy died compared with 2.8% of those who did not have their thymus removed, equating to a 2.9-times higher risk of death. Also during that time, 7.4% of patients in the thymectomy group developed cancer compared with 3.7% of patients in the control group, for a 2.0-times higher risk.

The thymus is absolutely required for health. If it isn't there, people's risk of dying and risk of cancer is at least double. This indicates that the consequences of thymus removal should be carefully considered when contemplating thymectomy.

In an additional analysis involving all patients in the thymectomy group with more than five years of follow-up, the overall mortality rate was higher in the thymectomy group than in the general U.S. population (9.0% vs. 5.2%), as was mortality due to cancer (2.3% vs. 1.5%).

Kameron A. Kooshesh et al, Health Consequences of Thymus Removal in Adults, New England Journal of Medicine (2023). DOI: 10.1056/NEJMoa2302892

Comment by Dr. Krishna Kumari Challa on August 4, 2023 at 9:15am

A new discovery in a cause of inner-ear bone loss

Chronic inflammation of the middle ear can cause several problems and complications that can affect a person's hearing and balance. One such problem is the formation of a cholesteatoma, which is an abnormal collection of cells in the ear that can cause bone erosion if left untreated. In turn, this can cause symptoms such as hearing loss, dizziness, facial paralysis, and even a brain infection.

In a study published recently in Nature Communications, researchers have revealed the cause of cholesteatomas, which may help in developing new therapies for patients who are suffering from this disease.

Cholesteatomas are made up of cysts or bumps in the ear that consist of skin, collagen fibers, skin cells, fibroblasts, keratin, and dead tissue. There are many theories on how these cholesteatomas can cause bone erosion, including the activation of cells responsible for the breakdown of the minerals and matrix of the bone, the presence of inflammatory markers and enzymes, and the accumulation and pressure from dead cells and tissues in the ear. However, the exact mechanism for the creation of cholesteatomas remains unknown.

A cholesteatoma can still return or happen again even after its surgical removal, so it is important to know what is actually causing it.

To investigate this, researchers looked at human cholesteatoma tissues that were surgically removed from patients. A process called single-cell RNA sequencing analysis was employed to identify cells responsible for triggering bone erosion; these were called osteoclastogenic fibroblasts. This study demonstrated how these fibroblasts expressed an abundant amount of activin A, a molecule that regulates different physiologic functions of the body. The presence of activin A is said to cause bone erosion through a process in which specialized cells initiate bone resorption through a process wherein the minerals and matrix of the bones are broken down and absorbed by the body. 

The researchers were successful in showing the relationship between activin A and bone erosion in cholesteatoma.

Currently in clinical settings, the only effective treatment for cholesteatomas is complete surgical removal. However, the discovery of how a cholesteatoma can cause bone erosion in this study offers new hope for developing novel medical treatments as first-line management for cholesteatomas.

Single-cell transcriptomics of human cholesteatoma identifies an activin A-producing osteoclastogenic fibroblast subset inducing bone destruction, Nature Communications (2023). DOI: 10.1038/s41467-023-40094-3

Comment by Dr. Krishna Kumari Challa on August 4, 2023 at 9:02am

Genetic predisposition to atrial fibrillation accelerated by air pollution, research suggests

Research has connected the effects of air pollutants on the risk of atrial fibrillation (AF). In a paper, "Air pollution, genetic susceptibility, and the risk of atrial fibrillation: A large prospective cohort study," published in PNAS, researchers find long-term exposure to air pollutants increases the risk of AF, particularly among individuals with high genetic susceptibility.

Air pollutants have long been associated with cardiovascular diseases. Recent studies have linked short-term exposure to these pollutants with acute exacerbations of AF. Studies on twins suggest that genetic susceptibility plays a big part in the risk of AF, but these risk factors explain only about half of AF cases.

The current study focuses on the cumulative damage caused by long-term exposure to these pollutants, revealing an association between increased concentrations of particulate matter with aerodynamic diameters smaller than 2.5 μm (PM_2.5), particulate matter with diameters of 10 μm (PM₁₀), nitrogen dioxide (NO₂), and nitrogen oxide and the underlying genetic risk of AF.

Despite the visible haze that can come with smoke, dust or vehicle emissions, particle pollution is comprised of tiny non-visible elements under 10 μm, and these can travel deep into the lungs. For reference, the average width of human hair is around 70 μm.

The particles can be hundreds of different chemicals depending on their source. Direct emissions from agricultural, automotive, industrial, fire or construction sites will reflect what is coming from those sources. In the atmosphere, more environmentally complex sources like those emitted from power plants, heavy industries and automobile emissions can undergo reactions to produce chemicals like sulfur dioxide and nitrogen oxides.

When combining genetic susceptibility with high air pollutant levels, participants exposed to high air pollutants with high genetic risk had approximately 149–182% higher risk of AF than individuals with low genetic risk factors.

The study also found a significant additive risk interaction between PM₁₀ and NO₂ and genetic risk, with approximately 16.4–35.1% of cases attributable to the joint effects of these pollutants and genetic predisposition.

The combined effects of  air pollutants and genetic risk showed a dose-response manner, such that exposure to high air pollutant levels and having high genetic risk resulted in high AF chances.

Yudiyang Ma et al, Air pollution, genetic susceptibility, and the risk of atrial fibrillation: A large prospective cohort study, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2302708120

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