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Comment by Dr. Krishna Kumari Challa on November 1, 2024 at 10:42am

Causal relationship seen between GERD and hypertension

There is a positive causal relationship between gastroesophageal reflux disease (GERD) and hypertension, according to a study published online Sept. 23 in Frontiers in Cardiovascular Medicine.

Researchers  investigated the causal  between GERD and hypertension using a two-sample Mendelian randomization analysis.

The researchers reported that a total of 16 single nucleotide polymorphisms strongly associated with GERD were screened out, and the inverse variance weighting suggested a causal relationship between GERD and hypertension (odds ratio, 1.057). A similar relationship was seen using a weighted median (odds ratio, 1.051). No heterogeneity or horizontal pleiotropy was seen, suggesting a robustness of the outcome.

"Although the specific mechanism was not elucidated, this study provides another perspective on the risk factors for the development of hypertension," the authors write. "Timely diagnosis and treatment of GERD can significantly improve and reduce the development of associated hypertension and deserves further research and application."

Weige Li et al, Study of the causal relationship between gastroesophageal reflux disease and hypertension through two-sample Mendelian randomization analysis, Frontiers in Cardiovascular Medicine (2024). DOI: 10.3389/fcvm.2024.1326348

Comment by Dr. Krishna Kumari Challa on November 1, 2024 at 10:21am

Low sugar intake in utero and in early childhood found to significantly reduce risk of midlife chronic disease

A low-sugar diet in utero and in the first two years of life can meaningfully reduce the risk of chronic diseases in adulthood, a new study has found, providing compelling new evidence of the lifelong health effects of early-life sugar consumption.

Published in Science, the study finds that children who experienced sugar restrictions during their first 1,000 days after conception had up to 35% lower risk of developing type 2 diabetes and as much as 20% less risk of hypertension as adults. Low sugar intake by the mother prior to birth was enough to lower risks, but continued sugar restriction after birth increased the benefits.

 Tadeja Gracner et al, Exposure to sugar rationing in the first 1000 days of life protected against chronic disease, Science (2024). DOI: 10.1126/science.adn5421

Comment by Dr. Krishna Kumari Challa on November 1, 2024 at 10:16am

Scientists engineer 'glowing' gel to improve eye surgery

Cataracts—a condition that causes clouding of the eye's lens and deteriorating vision—will affect nearly everyone who lives long enough. Now  scientists have pioneered a new color-changing hydrogel that could reduce complications from cataract surgery, one of the world's most commonly performed procedures.

During cataract surgery, doctors remove the cloudy lens and replace it with an artificial one. The procedure requires injecting a clear hydrogel to keep the eye inflated and protect the cornea. However, incomplete removal of this gel can lead to increased eye pressure, pain, and even long-term vision loss.

Researchers have created a clear gel that turns fluorescent green under blue light, allowing surgeons to verify complete removal following surgery. This innovation could enhance both the safety and efficiency of cataract surgery and other eye procedures, according to the researchers.

Now, when surgeons finish up a case, they can rest assured that all the gel has been removed versus beforehand when they just had to do their best and hope they'd gotten it all.

Their results were featured on the cover of the Journal of Cataract & Refractive Surgery.

 Erick E. Rocher et al, Fluorescein-conjugated hyaluronic acid enables visualization of retained ophthalmic viscosurgical device in anterior chamber, Journal of Cataract & Refractive Surgery (2024). DOI: 10.1097/j.jcrs.0000000000001503

Comment by Dr. Krishna Kumari Challa on November 1, 2024 at 10:01am

It's time to rewrite the textbooks: 

Chemists just broke a 100-year-old rule

I love this!

Chemists have found a big problem with a fundamental rule of organic chemistry that has been around for 100 years—it's just not true. And they say, It's time to rewrite the textbooks.

Organic molecules, those made primarily of carbon, are characterized by having specific shapes and arrangements of atoms. Molecules known as olefins have double bonds, or alkenes, between two carbon atoms. The atoms, and those attached to them, ordinarily lie in the same 3D plane. Molecules that deviate from this geometry are uncommon.

The rule in question, known as Bredt's rule in textbooks, was reported in 1924. It states that molecules cannot have a carbon-carbon double bond at the ring junction of a bridged bicyclic molecule, also known as the "bridgehead" position. The double bond on these structures would have distorted, twisted geometrical shapes that deviate from the rigid geometry of alkenes taught in textbooks.

Olefins are useful in pharmaceutical research, but Bredt's rule has constrained the kind of synthetic molecules scientists can imagine making with them and prevented possible applications of their use in drug discovery.

A paper published by scientists in the journal Science has invalidated that idea. They show how to make several kinds of molecules that violate Bredt's rule, called anti-Bredt olefins, or ABOs, allowing chemists to find practical ways to make and use them in reactions.

People aren't exploring anti-Bredt olefins because they think they can't (very bad for science).

"We shouldn't have rules like this—or if we have them, they should only exist with the constant reminder that they're guidelines, not rules. It destroys creativity when we have rules that supposedly can't be overcome", say the scientists.

What this study shows is that contrary to one hundred years of conventional wisdom, chemists can make and use anti-Bredt olefins to make value-added products.

There's a big push in the pharmaceutical industry to develop chemical reactions that give three-dimensional structures like these because they can be used to discover new medicines.

Luca McDermott et al, A solution to the anti-Bredt olefin synthesis problem, Science (2024). DOI: 10.1126/science.adq3519. www.science.org/doi/10.1126/science.adq3519

Comment by Dr. Krishna Kumari Challa on November 1, 2024 at 8:59am

Part 2

Comment by Dr. Krishna Kumari Challa on November 1, 2024 at 8:55am

Bats have acoustic cognitive maps

Echolocating bats have been found to possess an acoustic cognitive map of their home range, enabling them to navigate over kilometer-scale distances using echolocation alone.

This finding, published in Science, was demonstrated by researchers.

Would you be able to instantly recognize your location and find your way home from any random point within a three-kilometer radius, in complete darkness, with only a flashlight to guide you?

Echolocating bats face a similar challenge, with a local and directed beam of sound—their echolocation—to guide their way. Bats have long been known for their use of echolocation to avoid obstacles and orient themselves.

The researchers have now shown that bats can identify their location even after being displaced and use echolocation to perform map-based navigation over long distances.

Remarkably in experiments, even with echolocation alone, 95% of the displaced bats  returned to their roosts within minutes, demonstrating that bats can conduct kilometer-scale navigation using only this highly directional, and relatively local, mode of sensing. However, it was also shown that, when available, bats improve their navigation using vision.

The model created revealed that bats tend to fly near environmental features with higher "echoic entropy"—areas that provide richer acoustic information.

Bats can use this acoustic information to distinguish between environmental features such as a tree and a road, and thus use them as acoustic landmarks.

After being displaced, these  bats first identify their new location and then fly home, using environmental features with distinctive acoustic cues as landmarks. This behaviour suggests they possess an acoustic mental map of their home range.

Aya Goldshtein, Acoustic cognitive map-based navigation in echolocating bats, Science (2024). DOI: 10.1126/science.adn6269. www.science.org/doi/10.1126/science.adn6269

Comment by Dr. Krishna Kumari Challa on October 31, 2024 at 11:55am

Once again, tuberculosis becomes world's top infectious disease killer

In the highest tally ever recorded for tuberculosis cases, the World Health Organization report that over 8 million people worldwide were diagnosed with the lung disease last year.

Of that number, 1.25 million people died of TB, the new report found, meaning that it is once again the leading cause of deaths from infectious disease after COVID-19 displaced it briefly during the pandemic.

The fact that TB still kills and sickens so many people is an outrage, when we have the tools to prevent it, detect it and treat it," WHO Director-General Dr. Tedros Adhanom Ghebreyesus said in an agency news release. "WHO urges all countries to make good on the concrete commitments they have made to expand the use of those tools, and to end TB."

Some countries are hit harder by the disease than others. It continues to mostly affect people in Southeast Asia, Africa and the Western Pacific. India, Indonesia, China, the Philippines and Pakistan account for more than half of the world's cases, the WHO noted.

According to the report, 55% of people who developed TB were men, while 33% were women and 12% were children and young adolescents. Many new TB cases were driven by five major risk factors: undernutrition, HIV infection, alcohol use disorders, smoking [especially among men] and diabetes.

Tackling these issues, along with other social determinants such as poverty, requires a coordinated approach, the WHO added.

https://www.who.int/news/item/29-10-2024-tuberculosis-resurges-as-t...

Comment by Dr. Krishna Kumari Challa on October 31, 2024 at 11:47am

Electric fans fail to lower core body temperature of seniors during heat waves, study finds

A team of physiologists at the University of Ottawa's Human and Environmental Physiology Research Unit reports that use of an electric fan during periods of high temperatures by older people does not lower core body temperatures. In their study, published in JAMA, the group conducted experiments with elderly volunteers using fans in high-temperature conditions.

As several heat waves have struck parts of North America, high numbers of older people have died of heat stroke. This was notable due to the location of many of the deaths—the Pacific Northwest, where extremely high temperatures are rare. Because of the rarity of such high temperatures, many people in the region do not have air conditioners. Prior research has shown that older people are at higher risk of dying of heat stroke due to their lessened ability to reduce their body temperature. One notable problem is less efficient sweating.

During heat waves, officials in the affected regions suggested that older people without access to air conditioning use electric fans to stay cool. In this new effort, the research team tested the approach to see if the advice was valid.

The researchers recruited 18 people ranging in age from 65 to 72, who sat in a climate-controlled temperature chamber with an electric fan. The temperature and the fan settings were both controlled by the research team. All the volunteers were monitored during the experiments to ensure they did not become overheated.

The researchers kept the temperature inside the chamber at a steady 36°C, with a humidity level of 45%. The fans had three spin settings: off, slow and fast. All three settings were tested with the volunteers.

The researchers found that neither the slow nor the fast setting had any measurable impact on core body temperature—it was the same as if the fan was off. They also found that the slow setting did little to make the volunteers feel cooler, but the fast setting did, which, they suggest, was dangerous. Because they felt somewhat cool, the volunteers did not realize that their core body temperatures might be rising to dangerous levels.

 Fergus K. O'Connor et al, Effect of Electric Fans on Body Core Temperature in Older Adults Exposed to Extreme Indoor Heat, JAMA (2024). DOI: 10.1001/jama.2024.19457

Comment by Dr. Krishna Kumari Challa on October 31, 2024 at 11:17am

Some wildfire suppressants contain heavy metals and could contaminate the environment

In fire-prone areas, water isn't the only thing used to quell blazes. Wildland firefighters also apply chemical or synthetic suppressants. Researchers reporting in Environmental Science & Technology Letters explored whether these suppressants could be a source of elevated metal levels sometimes found in waterways after wildfires are extinguished.

Several products they investigated contained high levels of at least one metal, including chromium and cadmium, and could contribute to post-fire increases in the environment.

Wildfires are associated with the release of toxic heavy metals to the environment, but until now, it was assumed that these metals came from natural sources like soil. We now know that fire retardants may contribute to these metal releases.

Wildfire suppressant products, which are intended to inhibit fire activity before and after water evaporates, include fire retardants, water enhancers and foams. As wildfires have become more frequent and severe, larger volumes of water along with chemical and synthetic suppressants—sprayed from the ground and dropped from planes—have been required to extinguish them. Although manufacturers identify most of the active ingredients in suppressants, some components are proprietary. In addition, previous researchers have observed increased concentrations of potentially toxic metals in soil and streams after wildfires.

These results show that fire suppression activities could contribute to elevated metal levels in the environment but that more work is needed to determine potential risks to human and environmental health.

Marella H. Schammel et al, Metals in Wildfire Suppressants, Environmental Science & Technology Letters (2024). DOI: 10.1021/acs.estlett.4c00727

Comment by Dr. Krishna Kumari Challa on October 31, 2024 at 10:34am

Researchers show nanoplastics can reduce the effectiveness of antibiotics

In a recent study, an international research team has investigated how nanoplastic particles deposited in the body affect the effectiveness of antibiotics.

The study showed that the plastic particles not only impair the effect of the drugs, but could also promote the development of antibiotic-resistant bacteria. These results were recently published in the journal Scientific Reports.

The focus was on the broad-spectrum antibiotic tetracycline, which is used to treat many bacterial infections, such as those of the respiratory tract, skin or intestines.

When it came to plastics, the choice fell on polyethylene (PE), polypropylene (PP) and polystyrene (PS), which are ubiquitous components of packaging materials, as well as nylon 6,6 (N66), which is contained in many textiles such as clothing, carpets, sofa covers and curtains. Nanoplastics are smaller than 0.001millimeters and are considered particularly harmful to humans and the environment due to their small size.

Using complex computer models, the team was able to prove that the nanoplastic particles can bind tetracycline and thus impair the effectiveness of the antibiotic. The binding was particularly strong with nylon.

The micro- and nanoplastic load is around five times higher there than outdoors. Nylon is one of the reasons for this: it is released from textiles and enters the body via respiration, for example.

As the study results show, the binding of tetracycline to nanoplastic particles can reduce the biological activity of the antibiotic. At the same time, binding to nanoplastics could lead to the antibiotic being transported to unintended sites in the body, causing it to lose its targeted effect and possibly cause other undesirable effects.

This increase in concentration could lead to the development of antibiotic-resistant bacteria. Plastics such as nylon 6,6, but also polystyrene, which bind more strongly to tetracycline, could therefore increase the risk of resistance.

The study shows that exposure to nanoplastics is not only a direct health risk, but can also indirectly influence the treatment of diseases. If nanoplastics reduce the effectiveness of antibiotics, the dosage poses a massive problem.

Leonard Dick et al, The adsorption of drugs on nanoplastics has severe biological impact, Scientific Reports (2024). DOI: 10.1038/s41598-024-75785-4

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