Comment

Comment by Dr. Krishna Kumari Challa on November 17, 2024 at 12:30pm

The 70% increase is significant, though even with high maternal stress, epilepsy remains an extremely rare condition, and other factors seemed more prominent in the study analyses. Low birth weight was associated with a 180% increased risk by age 1, introduction to artificial milk in the first month showed a 203% increased risk by age 2, and having any chromosome abnormalities increased the risk by 2100% at age 1, 1567% at age 2, and 1000% at age 3.

 Yuto Arai et al, The impact of maternal prenatal psychological distress on the development of epilepsy in offspring: The Japan Environment and Children's Study, PLOS ONE (2024). DOI: 10.1371/journal.pone.0311666

Part 2

Comment by Dr. Krishna Kumari Challa on November 17, 2024 at 12:27pm

Maternal stress linked to increased early onset epilepsy in children

 Researchers in Japan have linked maternal psychological distress during pregnancy to an increased risk of epilepsy in children.

Epilepsy affects 65 million people globally and is one of the most prevalent neurological disorders. Individuals with epilepsy often face discrimination and social stigma, enduring stress from living with a chronic, unpredictable disease.
Early onset of epilepsy before the age of three is associated with high rates of drug resistance and developmental delays. Previous studies have identified potential factors like placental abruption, eclampsia, infection during pregnancy, low birth weight, and artificial milk as risk factors for early childhood epilepsy.

In a research article, "The impact of maternal prenatal psychological distress on the development of epilepsy in offspring: The Japan Environment and Children's Study," published in PLOS ONE, researchers used a dataset obtained from the Japan Environment and Children's Study, a nationwide birth cohort involving nearly 100,000 participants, to evaluate the association between six-item Kessler Psychological Distress Scale (K6) scores of mothers and epilepsy among 1 to 3-year-olds.

Self-reported data on 97,484 children were retrospectively analyzed for connections between the stress scores of expecting mothers and epilepsy outcomes in their children.

Maternal psychological distress was assessed using the six-item Kessler Psychological Distress Scale (K6), administered twice during pregnancy: once in the first half (median 15.1 weeks) and again in the second half (median 27.4 weeks). Participants were categorized into six groups based on K6 scores, classified as either low (4 or less) or moderate (5 or 6) distress at each time point.
Children diagnosed with epilepsy at ages 1, 2, and 3 numbered 89 (0.1%), 129 (0.2%), and 149 (0.2%), respectively. Findings indicated that a maternal K6 score of 5 or higher at both time points was associated with 70% higher epilepsy diagnosis ratios among children aged 1 to 3 years. Multivariate analysis confirmed this association, even after adjusting for potential confounding factors like low birth weight and chromosomal abnormalities.

The study concludes that "...environmental adjustments to promote relaxation in pregnant women are needed," which makes a tremendous amount of good sense, though they continue "...to prevent the development of epilepsy in their offspring," which might be a little more than what the study is actually telling us.

Part 1

Comment by Dr. Krishna Kumari Challa on November 17, 2024 at 12:24pm

Altering two genes to produce sweeter tomatoes without sacrificing size, weight or yield

A team of horticulturists, bio-breeders and agriculture specialists affiliated with a host of institutions across China has produced sweeter tomatoes without sacrificing size, weight or yield by altering two of their genes. In their study, published in the journal Nature, the group modified the genes of a tomato variant that coded for proteins that lowered levels of enzymes related to sugar production.

Over the past several centuries, farmers around the world have crossbred tomato plants with the aim of improving yields and increasing fruit size. The result has been a massive growth in both. Unfortunately, making tomatoes bigger has also made them less sweet. Past efforts to make large modern tomatoes sweeter have resulted in smaller yields.
For this new study, the research team took a new approach. They began by looking into the reason for the loss of sweetness in tomatoes and partially corrected crossbreeding effects on the tomato genome.

The research team discovered two genes in multiple tomato variants that were more active in larger varieties. Called SlCDPK26 and SlCDPK27, the two genes were found to code for proteins that lowered the levels of enzymes that produce sugar. The researchers next genetically modified the genome of a variety of large tomato called Money Maker to disable the two genes they had identified.

Plants grown with the modification produced tomatoes with a 30% increase in fructose and glucose levels with no reduction in size or weight. The team further confirmed that the tomatoes were sweeter by tasting them. The gene alterations did not diminish yields—the only other difference they found was that the tomatoes produced fewer seeds, which were also smaller. They suggest consumers would probably like this added feature.

Jinzhe Zhang et al, Releasing a sugar brake generates sweeter tomato without yield penalty, Nature (2024). DOI: 10.1038/s41586-024-08186-2

Amy Lanctot et al, Tomato engineering hits the sweet spot to make big sugar-rich fruit, Nature (2024). DOI: 10.1038/d41586-024-03302-8

Comment by Dr. Krishna Kumari Challa on November 17, 2024 at 12:10pm

Scientists discover laser light can cast a shadow

Can light itself cast a shadow? Researchers have found that under certain conditions, a laser beam can act like an opaque object and cast a shadow. The discovery challenges the traditional understanding of shadows and opens new possibilities for technologies that could use a laser beam to control another laser beam.

Laser light casting a shadow was previously thought impossible since light usually passes through other light without interacting. This new demonstration of a very counter-intuitive optical effect invites us to reconsider our notion of shadow.

In Optica, researchers describe how they used a ruby crystal and specific laser wavelengths to show that a laser beam could block light and create a visible shadow due to a nonlinear optical process. This effect occurs when light interacts with a material in an intensity-dependent way and can influence another optical field.

The new research is part of a larger exploration into how a light beam interacts with another light beam under special conditions and nonlinear optical processes.

 The researchers directed a high-power green laser through a cube made of standard ruby crystal and illuminated it with a blue laser from the side. When the green laser enters the ruby, it locally changes the material response to the blue wavelength. The green laser acts like an ordinary object while the blue laser acts like illumination.

The interaction between the two light sources created a shadow on a screen that was visible as a dark area where the green laser blocked the blue light. It met all the criteria for a shadow because it was visible to the naked eye, followed the contours of the surface it fell on and followed the position and shape of the laser beam, which acted as an object.

The laser shadow effect is a consequence of optical nonlinear absorption in the ruby. The effect occurs because the green laser increases the optical absorption of the blue illuminating laser beam, creating a matching region in the illuminating light with lower optical intensity. The result is a darker area that appears as a shadow of the green laser beam.

This discovery expands our understanding of light-matter interactions and opens up new possibilities for utilizing light in ways we hadn't considered before.

The researchers experimentally measured the dependence of the shadow's contrast on the laser beam's power, finding a maximum contrast of approximately 22%, similar to the contrast of a tree's shadow on a sunny day. They also developed a theoretical model and showed that it could accurately predict the shadow contrast.

 Raphael Abrahao et al, The shadow of a laser beam, Optica (2024). DOI: 10.1364/OPTICA.534596

Comment by Dr. Krishna Kumari Challa on November 16, 2024 at 4:09pm

Spontaneous mutations of DNA arise in all living cells, including those within bacteria. Some of these mutations lead to antibiotic resistance. Researchers focused on physiological mechanisms related to ribosomes, the micro machines within cells that play a key role in synthesizing proteins and translating genetic codes.
All cells rely on charged ions such as magnesium ions to survive. Ribosomes are dependent upon magnesium ions since this metal cation helps stabilize their structure and function.

However, atomic-scale modeling during the new research found that mutant ribosome variants that bestow antibiotic resistance excessively compete for magnesium ions with adenosine triphosphate (ATP) molecules, which provide energy to drive living cells. Mathematical models further showed that this results in a ribosome versus ATP tug-of-war over a limited supply of magnesium in the cell.
Studying a ribosome variant within Bacillus subtilis called "L22," the researchers found that competition for magnesium hinders the growth of L22 more than a normal "wild type" ribosome that is not resistant to antibiotics. Hence, the competition levies a physiological toll linked to mutant bacteria with resistance.
This newly discovered weakness can now be used as a target to counteract antibiotic resistance without the use of drugs or toxic chemicals. For example, it may be possible to chelate magnesium ions from bacterial environments, which should selectively inhibit resistant strains without impacting the wild type bacteria that may be beneficial to our health.

Eun Chae Moon et al, Physiological cost of antibiotic resistance: Insights from a ribosome variant in bacteria, Science Advances (2024). DOI: 10.1126/sciadv.adq5249. www.science.org/doi/10.1126/sciadv.adq5249

Part 2

Comment by Dr. Krishna Kumari Challa on November 16, 2024 at 4:06pm

Scientists propose drug-free method to combat antibiotic-resistant bacteria

Recent estimates indicate that deadly antibiotic-resistant infections will rapidly escalate over the next quarter century. More than 1 million people died from drug-resistant infections each year from 1990 to 2021, a recent study reported, with new projections surging to nearly 2 million deaths each year by 2050.

In an effort to counteract this public health crisis, scientists are looking for new solutions inside the intricate mechanics of bacterial infection. A study by researchers  has discovered a vulnerability within strains of bacteria that are antibiotic resistant. They  investigated the antibiotic resistance of the bacterium Bacillus subtilis.

Their research was motivated by the question of why mutant variants of bacteria do not proliferate and take over the population once they have developed an antibiotic-resistant advantage. With an upper hand over other bacteria lacking similar antibiotic resistance, such bacteria should become dominant. Yet they are not. Why?

The answer, reported in the journal Science Advances, is that antibiotic resistance comes at a cost. While antibiotic resistance provides some advantages for the bacteria to survive, the team discovered that it's also linked with a physiological limitation that hinders potential dominance.

This fact, the researchers note, potentially could be exploited to stop the spread of antibiotic resistance.

The researchers discovered an Achilles heel of antibiotic resistant bacteria. They can now  take advantage of this cost to suppress the establishment of antibiotic resistance without drugs or harmful chemicals.

Part 1

Comment by Dr. Krishna Kumari Challa on November 16, 2024 at 3:17pm

Environmental health of waste explained in 101 seconds 

Comment by Dr. Krishna Kumari Challa on November 16, 2024 at 3:13pm

The decline in global freshwater reported in the study began with a massive drought in northern and central Brazil, and was followed shortly by a series of major droughts in Australasia, South America, North America, Europe, and Africa. Warmer ocean temperatures in the tropical Pacific from late 2014 into 2016, culminating in one of the most significant El Niño events since 1950, led to shifts in atmospheric jet streams that altered weather and rainfall patterns around the world.

However, even after El Niño subsided, global freshwater failed to rebound. In fact, Rodell and team report that 13 of the world's 30 most intense droughts observed by GRACE occurred since January 2015. Researchers suspect that global warming might be contributing to the enduring freshwater depletion.
Global warming leads the atmosphere to hold more water vapor, which results in more extreme precipitation. While total annual rain and snowfall levels may not change dramatically, long periods between intense precipitation events allow the soil to dry and become more compact. That decreases the amount of water the ground can absorb when it does rain.
"Warming temperatures increase both the evaporation of water from the surface to the atmosphere, and the water-holding capacity of the atmosphere, increasing the frequency and intensity of drought conditions.

Matthew Rodell et al, An Abrupt Decline in Global Terrestrial Water Storage and Its Relationship with Sea Level Change, Surveys in Geophysics (2024). DOI: 10.1007/s10712-024-09860-w

Part 2

Comment by Dr. Krishna Kumari Challa on November 16, 2024 at 3:11pm

NASA satellites reveal abrupt drop in global freshwater levels

An international team of scientists using observations from NASA-German satellites found evidence that Earth's total amount of freshwater dropped abruptly starting in May 2014 and has remained low ever since. Reporting in Surveys in Geophysics, the researchers suggested the shift could indicate Earth's continents have entered a persistently drier phase.

From 2015 through 2023, satellite measurements showed that the average amount of freshwater stored on land—that includes liquid surface water like lakes and rivers, plus water in aquifers underground—was 290 cubic miles (1,200 cubic km) lower than the average levels from 2002 through 2014.

That's two and a half times the volume of Lake Erie lost.

During times of drought, along with the modern expansion of irrigated agriculture, farms and cities must rely more heavily on groundwater, which can lead to a cycle of declining underground water supplies: freshwater supplies become depleted, rain and snow fail to replenish them, and more groundwater is pumped.

The reduction in available water puts a strain on farmers and communities, potentially leading to famine, conflicts, poverty, and an increased risk of disease when people turn to contaminated water sources, according to a UN report on water stress published in 2024.

The team of researchers identified this abrupt, global decrease in freshwater using observations from the Gravity Recovery and Climate Experiment (GRACE) satellites, operated by the German Aerospace Center, German Research Centre for Geosciences, and NASA. GRACE satellites measure fluctuations in Earth's gravity on monthly scales that reveal changes in the mass of water on and under the ground. The original GRACE satellites flew from March 2002 to October 2017. The successor GRACE–Follow On (GRACE–FO) satellites launched in May 2018.

Part 1

Comment by Dr. Krishna Kumari Challa on November 16, 2024 at 3:06pm

How stress changes our memories: Engrams and the endocannabinoid system may inform new PTSD treatments

Researchers have uncovered that stress changes how our brain encodes and retrieves aversive memories, and discovered a promising new way to restore appropriate memory specificity in people with post-traumatic stress disorder (PTSD).

If you stumble during a presentation, you might feel stressed the next time you have to present because your brain associates your next presentation with that one poor and aversive experience. This type of stress is tied to one memory.

But stress from traumatic events like violence or generalized anxiety disorder can spread far beyond the original event, known as stress-induced aversive memory generalization, where fireworks or car backfires can trigger seemingly unrelated fearful memories and derail your entire day. In the case of PTSD, it can cause much greater negative consequences.

In a study published in Cell, researchers identify the biological processes behind stress-induced aversive memory generalization and highlight an intervention which could help restore appropriate memory specificity for people with PTSD.

People with PTSD show fearful responses to safe situations or environments. Researchers  have found a way to limit this fearful response to specific situations and potentially reduce the harmful effects of PTSD. the research team was able to block endocannabinoid  receptors on interneurons, and limit stress-induced aversive memory generalization to the specific, appropriate memory.

Stress disrupts engram ensembles in lateral amygdala to generalize threat memory in mice, Cell (2024). DOI: 10.1016/j.cell.2024.10.034. www.cell.com/cell/fulltext/S0092-8674(24)01216-9

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