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Comment by Dr. Krishna Kumari Challa on July 16, 2025 at 6:50am

Comparing first-trimester UTI antibiotics and congenital malformations

Researchers produced a population-based cohort study suggesting first-trimester treatment of urinary tract infection (UTI) with trimethoprim-sulfamethoxazole (TMP-SMX) is associated with a higher risk of congenital malformations compared with β-lactam antibiotics, whereas nitrofurantoin and fluoroquinolones show no clear elevated risk.

Untreated UTIs are associated with adverse perinatal outcomes, including preterm birth, low birth weight, pyelonephritis, and maternal sepsis. Routine screening for asymptomatic UTI is recommended at the initial prenatal visit and frequently leads to antibiotic treatment during the first trimester.

Many antibiotics can cross the placenta, including TMP and SMX, which can inhibit folic acid metabolism and interfere with rapidly growing fetal tissues.

The American College of Obstetricians and Gynecologists (ACOG) suggests that nitrofurantoin and TMP-SMX be avoided during the first trimester when possible. Despite this suggestion, many clinicians have been slow to adopt the guidance and nitrofurantoin and TMP-SMX combined still account for more than half of first-trimester UTI prescriptions.

In the study, "First-Trimester Antibiotic Use for Urinary Tract Infection and Risk of Congenital Malformations," published in JAMA Network Open, researchers designed a population-based cohort analysis to compare malformation risk following first-trimester exposure to antibiotics nitrofurantoin, TMP-SMX, fluoroquinolones, and β-lactams.

Among 71,604 pregnancies considered during the research work, 42,402 individuals (59.2%) were exposed to nitrofurantoin, 3,494 (4.9%) to TMP-SMX, 3,663 (5.1%) to fluoroquinolones, and 22,045 (30.8%) to β-lactams.

Unadjusted absolute risk of any congenital malformation per 1,000 infants was 19.8 for β-lactams, 21.2 for nitrofurantoin, 23.5 for fluoroquinolones, and 26.9 for TMP-SMX.

After adjusting for confounding, TMP-SMX was associated with a higher risk of any malformation compared to β-lactams (risk ratio, 1.35; 95% CI, 1.04–1.75). For nitrofurantoin and fluoroquinolones, adjusted risk was similar to β-lactams.

TMP-SMX exposure was associated with increased risk of severe cardiac malformations (risk ratio, 2.09; 95% CI, 1.09–3.99), other cardiac malformations (risk ratio, 1.52; 95% CI, 1.02-2.25), and cleft lip and palate (risk ratio, 3.23; 95% CI, 1.44–7.22).

Analyses of other malformation types did not show consistent differences by antibiotic group, and some estimates were imprecise. Sensitivity analyses yielded results consistent with the primary findings.

 Sarah S. Osmundson et al, First-Trimester Antibiotic Use for Urinary Tract Infection and Risk of Congenital Malformations, JAMA Network Open (2025). DOI: 10.1001/jamanetworkopen.2025.19544

Comment by Dr. Krishna Kumari Challa on July 15, 2025 at 10:00am

Chronological age determined within 1.36 years using DNA methylation patterns

Researchers  have developed an exceptionally accurate method for predicting chronological age from DNA, based on two short genomic regions. Using deep learning networks analyzing DNA methylation patterns at a single-molecule resolution, they achieve age predictions with a median error as low as 1.36 years in individuals under 50. The method is unaffected by smoking, BMI, and sex, and has potential applications in forensics, aging research, and personalized medicine.

Using cutting-edge artificial intelligence, the scientists created a tool called MAgeNet that can determine a person's chronological age—the number of years since birth—with a margin of error as small as 1.36 years for individuals under 50. And all it takes is a simple blood draw.

It turns out that the passage of time leaves measurable marks on our DNA and this new model decodes those marks with astonishing precision.

The secret lies in how our DNA changes over time through a process called methylation—the chemical "tagging" of DNA by methyl group (CH₃) . By zooming in on just two key regions of the human genome, the team was able to read these changes at the level of individual molecules, then use deep learning to translate them into accurate age predictions.

The study, published in Cell Reports, analyzed blood samples from over 300 healthy people, as well as data from a decade-long longitudinal analysis of the Jerusalem Perinatal Study (JPS). As they show, the model worked consistently across a range of variables—like smoking, body weight, sex, and even different signs of biological aging.

Beyond potential medical uses, the method could also revolutionize forensic science by allowing experts to estimate a suspect's age from just a trace of DNA—something existing tools struggle to do.

 Time is encoded by methylation changes at clustered CpG sites, Cell Reports (2025). DOI: 10.1016/j.celrep.2025.115958. www.cell.com/cell-reports/full … 2211-1247(25)00729-6

Comment by Dr. Krishna Kumari Challa on July 15, 2025 at 6:51am

A few bright buildings light up the entire night sky

When millions of people turn off their lights for Earth Hour each year, something remarkable happens in the night sky above cities. New research from Hong Kong published in Scientific Reports shows that just a small number of decorative buildings and advertising boards can dramatically brighten the entire urban night sky and when they go dark, the sky becomes up to 50% darker.

The scientists studied 14 years of Earth Hour data from 2011 to 2024 in Hong Kong, using specialized light sensors to measure exactly how much the night sky changed when the city participated in the global lights-out event.
The research team discovered that the most significant improvements in night sky darkness came from turning off lights in central business districts, particularly the decorative lighting on building facades and large LED advertising screens. Using crowdsourced photographs from social media, they could pinpoint exactly which buildings went dark during Earth Hour and correlate this with measurements of sky brightness.

Interestingly, the weekend lighting patterns during Earth Hour remained largely unchanged, suggesting that the dramatic darkening came specifically from commercial and decorative lighting rather than everyday residential use. This finding challenges common assumptions about what contributes most to light pollution in cities.

The researchers didn't just measure overall brightness, they analyzed the specific colors of light pollution using spectroscopic sensors. They found that the biggest reductions occurred in blue-green wavelengths (445–500 nanometers), green (500–540 nanometers), and orange-red (615–650 nanometers) ranges. These correspond precisely to the peak emissions from LED advertising boards that dominate many urban landscapes.
They also detected significant reductions in the yellow-orange spectrum (585–595 nanometers), which matches the signature of metal halide floodlights commonly used to illuminate buildings and large outdoor advertisements. This spectral analysis provides a detailed fingerprint of exactly which types of artificial lighting contribute most to urban light pollution.

This research finally offers hope for tackling light pollution without requiring massive citywide changes. Instead of asking every building to dim their lights, cities could achieve substantial improvements by focusing on a relatively small number of high-impact sources.

Chu Wing So et al, Natural experiments from Earth Hour reveal urban night sky being drastically lit up by few decorative buildings, Scientific Reports (2025). DOI: 10.1038/s41598-025-05279-4

Comment by Dr. Krishna Kumari Challa on July 15, 2025 at 6:47am

Sand and dust storms affect about 330 million people in over 150 countries

Sand and dust storms affect about 330 million people in over 150 countries and are taking an increasing toll on health, economies and the environment, the U.N. World Meteorological Organization says.

About 2 billion tons of dust are emitted yearly.

More than 80% of the world's dust comes from the deserts in North Africa and the Middle East, but it has a global impact because the particles can travel hundreds and even thousands of kilometers (miles) across continents and oceans.

Dust and dust storms are driven by climate change, land degradation and unsustainable practices.

Airborne particles from sand and dust storms contribute to 7 million premature deaths every year. They trigger respiratory and cardiovascular disease, and reduce crop yields by up to 25%, causing hunger and migration, according to experts. The storms' economic costs are "staggering."

Over 20 U.N. and international agencies are working to unite efforts on early warning systems for storms and to deal with other issues, including health and financing.

From land restoration and sustainable agriculture to integrated early warning systems, we have the tools to act, the exerts say.

Source: News Agencies

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Comment by Dr. Krishna Kumari Challa on July 14, 2025 at 12:46pm

Late eating is associated with impaired glucose metabolism

Our metabolic processes differ depending on the time of day and many of them are more active in the morning than in the evening. Although studies show that eating late in the day is associated with an increased risk of obesity and cardiovascular diseases, little is known about how the time we eat affects glucose metabolism and to what extent this is genetically defined.

Researchers  recently investigated this using data from a twin cohort from 2009–10. Their article was published in the journal eBioMedicine.

The circadian system is a hierarchically structured 24-hour time control system in the body that regulates behavior and metabolism via a central clock in the brain and peripheral clocks in organs such as the liver or pancreas. As a result, our metabolic processes differ depending on the time when we eat, which leads to diurnal fluctuations in glucose metabolism and the release of hormones after a meal.

Food intake itself acts as an important timer that synchronizes our internal clocks. Decoupling meal times from the natural light-dark rhythm, e.g., when working at night, can lead to an internal clock disorder and negative metabolic changes.

Previous studies have shown that eating late at night is associated with an increased risk of obesity and cardiovascular diseases.

However, little is known about how exactly the timing of food intake interacts with the individual circadian rhythm and thus influences glucose metabolism and the risk of diabetes. It is also unclear which mechanisms determine one's individual eating behavior, as it depends on the interaction of cultural, personal, physiological and genetic factors.

When someone eats during the course of a day in relation to the individual biological daily rhythm is measured as the interval between mealtime and the midpoint of sleep. The midpoint of sleep describes the time that lies exactly in the middle between falling asleep and waking up. It is a measure of the chronotype—in other words, whether someone is an early riser or a night owl.

This work was done on identical and fraternal twin pairs. 

Janna Vahlhaus et al, Later eating timing in relation to an individual internal clock is associated with lower insulin sensitivity and affected by genetic factors, eBioMedicine (2025). DOI: 10.1016/j.ebiom.2025.105737

Comment by Dr. Krishna Kumari Challa on July 12, 2025 at 12:10pm

The research team has unlocked the mechanisms for how this works: LINE1 recruits a non-working protein in the cells called NRBP1. This former kinase had lost its enzymatic functions through mutations in its gene over time. Since the uncontrolled reproduction of LINE1 is a major problem for the host cell, it has also developed a counter-mechanism over time. A slightly modified copy of this protein, the paralog NRBP2, marks NRBP1 so that it is recognized as waste and thereby disposed of.

The competition between the two proteins must be won by NRBP2 in order to prevent damage. Until now, both factors had only been noticed in cancer biology due to their different involvement in tumors, without their functions being known. An analysis of the evolutionary history of this competition shows that the blocking function of NRBP2 was probably acquired later in evolution in order to escape the destructive influence of NRBP1 and LINE1.

Wei Yang et al, Opposing roles of pseudokinases NRBP1 and NRBP2 in regulating L1 retrotransposition, Nature Communications (2025). DOI: 10.1038/s41467-025-61626-z

Part 2

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Comment by Dr. Krishna Kumari Challa on July 12, 2025 at 12:09pm

How the genome defends itself against internal enemies

An international research team has deciphered a mechanism of the evolutionary arms race in human cells. The findings provide insights into how mobile elements in DNA hijack cellular functions—and how cells can defend themselves against this in order to prevent conditions such as tumor formation or chronic inflammation.

An international research team has discovered how the LINE1 retrotransposon exploits a cell protein to become active itself, as occurs in tumors. At the same time, the researchers have also deciphered the cell's appropriate countermeasures to prevent conditions such as tumor formation or chronic inflammation. The results have been published in the journal Nature Communications.

"Sleepers" are the name the Secret Service gives agents who live inconspicuously in a society for years before being activated by their employers. The human genome contains thousands of such sleepers, known as retrotransposons. These—probably left over from virus attacks millions of years ago—are equipped with only minimal information to jump out of the genome and multiply when the opportunity arises. To do this, they misuse the enzyme machinery of human cells.

LINE1 is the name of the most common of these elements, accounting for almost 20% of the entire genome. When LINE1 becomes active, it copies itself and reintegrates itself into the genetic material  at a different location, thereby disrupting the cell's blueprint. This may sometimes be beneficial in terms of introducing diversity into the genome, but it can easily become uncontrollable, especially in progressive tumors.

In addition, active LINE1 can alert the cell's immune system, which can lead to chronic inflammation. Over the course of evolution, human cells have therefore developed many mechanisms to prevent precisely this activation. How LINE1 itself is mobilized has been largely misunderstood until now.

Part 1

Comment by Dr. Krishna Kumari Challa on July 12, 2025 at 8:48am

Artificial sweeteners leave bitter aftertaste for the environment

New research has found increasing levels of artificial sweeteners in wastewater treatment plants, with downstream impacts on the environment.

Artificial sweeteners, widely used in soft drinks, processed foods and sugar-free products such as toothpaste, are increasingly turning up far from supermarket shelves—in our rivers, waterways and natural ecosystems.

Some sugar substitutes have faced controversy for potential negative health effects, including links to type-2 diabetes, heart disease and cancer. Some also pose toxicity risks to aquatic animals. In zebrafish, sucralose causes birth defects and high levels of saccharin are neurotoxic.

In a systematic review, researchers examined the type and prevalence of artificial sweeteners in wastewater treatment plants across 24 countries, changes in concentration, and how effectively they are removed.

The researchers found that globally, sucralose, acesulfame, saccharin, and cyclamate are the most prevalent artificial sweeteners. The highest concentrations of these chemicals were found in the U.S., Spain, India and Germany.

Concentrations were 10%–30% higher in summer for most countries, however, in China they were highest in winter. Other artificial sweeteners found in wastewater include neotame, stevia, acesulfame-K and neo hesperidin dihydrochalcone (NHDC).

Unlike natural sugars, artificial sweeteners are designed to resist digestion, meaning they often pass through the human body largely unchanged. As a result, they enter wastewater systems where standard treatment processes aren't always equipped to deal with them.

The researchers found that while saccharin and cyclamate were easily removed from wastewater, other artificial sweeteners such as sucrose and acesulfame were harder to remove, and were released into the wider environment.

Sweeteners such as sucralose are incredibly persistent. Its chemical stability means it can survive both conventional and advanced treatment processes, so it eventually makes its way into rivers, lakes and coastal waters where it can affect aquatic ecosystems.

The study calls for ongoing monitoring, tighter regulations, and improved treatment technologies to reduce the environmental risks posed by artificial sweeteners.

 Jibin Li et al, Artificial sweeteners in wastewater treatment plants: A systematic review of global occurrence, distribution, removal, and degradation pathways, Journal of Hazardous Materials (2025). DOI: 10.1016/j.jhazmat.2025.138644

Comment by Dr. Krishna Kumari Challa on July 12, 2025 at 8:31am

How do rivers choose their path?

Rivers choose their path based on erosion, a discovery that could transform flood planning and restoration

Rivers are Earth's arteries. Water, sediment and nutrients self-organize into diverse, dynamic channels as they journey from the mountains to the sea. Some rivers carve out a single pathway, while others divide into multiple interwoven threads. These channel patterns shape flood risks, erosion hazards and ecosystem services for more than three billion people who live along river corridors worldwide.

Understanding why some waterways form single channels, while others divide into many threads, has perplexed researchers for over a century. Geographers recently mapped the thread dynamics along 84 rivers with 36 years of global satellite imagery to determine what dictates this aspect of river behavior.

The researchers found that rivers will develop multiple channels if they erode their banks faster than they deposit sediment on their opposing banks. This causes a channel to widen and divide over time.

The results, published in the journal Science, solve a longstanding quandary in the science of rivers. They also provide insight into  natural hazards and river restoration efforts.

Austin J. Chadwick et al, Single- and multithread rivers originate from (im)balance between lateral erosion and accretion, Science (2025). DOI: 10.1126/science.ads6567

Comment by Dr. Krishna Kumari Challa on July 12, 2025 at 8:26am

Quantum objects' dual nature mapped with new formula for 'wave-ness' and 'particle-ness'

Quantum mechanics has revolutionized our understanding of nature, revealing a bizarre world in which an object can act like both waves and particles, and behave differently depending on whether it is being 'watched'.

In recent decades, researchers exploring this wave-particle duality have learned to measure the relative "wave-ness" and "particle-ness" of quantum objects, helping to explain how and when they veer between wave-like or particle-like behaviors.

Now, in a paper for Physical Review Research, researchers at the Stevens Institute of Technology report an important new breakthrough: a simple but powerful formula that describes the precise closed mathematical relationship between a quantum object's "wave-ness" and "particle-ness."

Previous research showed that wave-ness and particle-ness could be expressed as an inequality, with the sum of an object's wave-like behaviors (such as visible interference patterns) and particle-like behaviors (such as the predictability of its path or location) being equal to or less than one.

That's important, because it means that if an object is fully wave-like, then it shows no particle-like behaviors, and vice versa. 

Such models were incomplete, however, because they can describe situations in which an object's wave-like and particle-like behaviors increase simultaneously—the opposite of the actual exclusive relationship between the two behaviors.

To remedy that, the authors introduced a new variable: the coherence of the quantum object.

That enables the calculation of both wave-ness and particle-ness with far more precision. By measuring the coherence in a system, in fact, it becomes possible to calculate a quantum object's level of wave-ness and particle-ness—not simply as "less than one," but as an exact value.

The relationship between wave-ness and particle-ness can then be plotted as an elegant curve on a graph—a perfect quarter-circle for a perfectly coherent system, and a flatter ellipse as the level of coherence declines.

 Pawan Khatiwada et al, Wave-particle duality ellipse and application in quantum imaging with undetected photons, Physical Review Research (2025). DOI: 10.1103/dyg6-l19j

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