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Comment by Dr. Krishna Kumari Challa on September 14, 2023 at 11:09am

Exposure to One Metal May Cause More Heart Disease Than Smoking or Cholesterol

Lead poisoning has a far greater impact on global health than previously thought, potentially contributing to over five million deaths a year and posing a similar threat to air pollution, modelling research suggested recently. The study, described as "a wake-up call", also estimated that exposure to the toxic metal causes young children in developing countries to lose an average of nearly six IQ points each. Lead pollution has been shown to cause a range of serious health problems, particularly relating to heart disease and the brain development of small children, resulting in leaded gasoline being banned worldwide. But people can still be exposed to the potent neurotoxin via food, soil, cookware, fertilisers, cosmetics, lead–acid car batteries and other sources. The researchers' model estimates that 5.5 million adults died from heart disease in 2019 because of lead exposure, 90 percent of them in low- and middle-income countries. That is six times higher than the previous estimate, and represents around 30 percent of all deaths from cardiovascular disease – the leading cause of death worldwide. It would mean that lead exposure is a bigger cause of heart disease than smoking or cholesterol.

https://www.businesswire.com/news/home/20230911634611/en/Pure-Earth....

https://www.thelancet.com/journals/lanplh/article/PIIS2542-5196(23)00166-3/fulltext

Comment by Dr. Krishna Kumari Challa on September 14, 2023 at 10:01am

Six of nine planetary boundaries now exceeded

A new study updates the planetary boundary framework and shows human activities are increasingly impacting the planet and, thereby, increasing the risk of triggering dramatic changes in overall Earth conditions.

For over 3 billion years, the interaction between life (represented by the planetary boundary, Biosphere Integrity) and climate have controlled the overall environmental conditions on Earth. Human activities, for example replacing nature with other land uses, changing the amount of water in rivers and in soil, the introduction of synthetic chemicals to the open environment, and the emission of greenhouse gases to the atmosphere all influence these interactions.

Respecting and maintaining interactions in the Earth system so that they remain similar to those that have controlled Earth conditions over the past ~12,000 years are critical for ensuring human activities do not trigger dramatic changes in Earth conditions—changes that likely would decrease the Earth's ability to support modern civilizations.

The nine "planetary boundaries" represent components of the global environment that regulate that stability and livability of the planet for people. The degree of breaching of the safe boundary levels is caused by human-driven activities impacting the components.

The planetary boundaries framework applies the newest scientific understanding of the functioning of the Earth system to identify a "safe operating space" for humanity by proposing limits for the extent to which human activities can be allowed to impact critical processes without risk of potentially triggering irreversible changes in the Earth conditions that support us.

For the first time, metrics for all boundaries are presented. Six of the boundaries are found to be transgressed, and transgression is increasing for all boundaries except the degradation of the Earth's ozone layer. A global focus on climate is not enough. Development of Earth system models that accurately reproduce interactions between boundaries, especially Climate and Biosphere Integrity, is an urgent priority.

The trend of increasing transgression of the boundaries is worrying.

Crossing six boundaries in itself does not necessarily imply a disaster will ensue but it is a clear warning signal. We can regard it as we do our own blood pressure. A BP over 120/80 is not a guarantee of a heart attack but it increases the risk of one. Therefore, we try to bring it down. For our own—and our children's—sakes we need to reduce the pressure on these six planetary boundaries.

The study, published in Science Advances, represents the third update of the framework carried out by 29 scientists from eight different countries.

Katherine Richardson, Earth beyond six of nine Planetary Boundaries, Science Advances (2023). DOI: 10.1126/sciadv.adh2458. www.science.org/doi/10.1126/sciadv.adh2458

Comment by Dr. Krishna Kumari Challa on September 14, 2023 at 9:37am

Exploit steals passwords by tapping into keystrokes

Add one more threat to the list of risks you take when you use your phone to conduct business at a local shop.

Researchers from universities in China and Singapore uncovered a security gap that permits snoops to lift your password by identifying your keystrokes.

Researchers are calling Wiki-Eve "the first WiFi-based hack-free keystroke eavesdropping system."

The cyberattack demonstrated by the researchers is made possible thanks to a feature in wireless communications called BFI, beamforming feedback information. BFI permits devices to more accurately transmit feedback about their location, sending signals specifically towards the routers that are to receive them, instead of dispersing them omnidirectionally. But one vulnerability of BFI, a component of the 802.11ac WiFi standard (also known as WiFi 5), is that it transmits data in cleartext. That means there is no need for physical hacking or cracking of an encryption key. The researchers devised a means of identifying a user's device and capturing the cleartext transmissions. Unlike older side-channel attacks, Wiki-Eve does not require planting rogue programs that trick a user into logging on to an illegitimate site. It also does not require setting up additional links to sense a target user's keystrokes. "Since BFI is transmitted from a smartphone to an AP [access point] in cleartext," the researchers said, "it can be overheard by any other Wi-Fi devices switching to monitor mode." Researchers said Wiki-Eve "achieves 88.9% inference accuracy for individual keystrokes and up to 65.8% top-10 accuracy for stealing passwords of mobile applications." Keystroke inference is the determination of what key is being pressed based on BFI data. As a user glides over keys on a keypad, the variations in wireless signals between device and base station can be tracked and identified with the aid of a deep-learning model. The team ran tests using numerical passwords since they are easier to decipher than alphanumeric passwords. They demonstrated Wiki-Eve by successfully lifting WeChat Pay passwords from a subject in a nearby conference room. Wiki-Eve joins a long list of side-channel attack methods. Such methods include acoustic cryptanalysis that interprets sounds produced by a device during transmission, cache attacks that probe access patterns, electromagnetic analysis that uses radiation to decipher information, and thermal attacks that track temperature variations to reveal activities. The study assumed users were engaging in activity over an unprotected network, common in public spaces such as coffeeshops, airports, train stations and other gathering places offering free WiFi.

Jingyang Hu et al, Password-Stealing without Hacking: Wi-Fi Enabled Practical Keystroke Eavesdropping, arXiv (2023). DOI: 10.48550/arxiv.2309.03492

Comment by Dr. Krishna Kumari Challa on September 13, 2023 at 12:44pm

'Hybrid' Brain Cells Have Been Discovered Hiding Inside Our Heads

An international team of scientists has found a whole new brand of brain cell hiding amongst neurons and their supporting units.

Surprisingly, the new cell type has characteristics of both, allowing it to serve an active role in neurological functions while still providing assistance to the nervous tissues around it.

Astrocytes are abundant cells in the brain that wrap around neuronal connections like 'glue'. For many years, neuroscientists assumed these cells were wholly passive, present only to protect neurons. The field was revolutionized when evidence arose that astrocytes may contribute to neuronal 'firing' by secreting glutamate, the brain's main neurotransmitter. But while studies in the lab suggest astrocytes are capable of releasing and absorbing glutamate, their role in a living, healthy brain is still being investigated. In exploring that hypothesis further, researchers from various institutions in the United Kingdom and Europe have stumbled upon a radical hybrid cell in the brains of mice. In between neurons and astrocytes, we now have a new kind of cell .

https://www.nature.com/articles/s41586-023-06502-w

Comment by Dr. Krishna Kumari Challa on September 13, 2023 at 12:41pm

Paleontologists May Have Found A Missing Branch Between Dinosaurs And Birds

Amidst remains of turtles and fish preserved in a southeastern China fossil bed, scientists have uncovered the skeleton of a dinosaur with curious bird-like features. Estimated to be roughly 30 million years older than any confirmed bird fossil, the finding could tell us a thing or two about the first critical steps into their evolution.

Researchers compared the new fossil, named Fujianvenator prodigiosus, with the remains of other dinosaurs from that time and more modern ones to identify the animal's place within the dino-bird family tree. The researchers determined the pheasant-sized and likely feathered Fujianvenator prodigiosus belonged to the ancestral group avialae which includes modern birds and their most closely related dinosaur ancestors. Remains of early bird ancestors like this are hard to come by, so they each hold important clues to the evolution of birds and the environment of Earth they experienced. 

For decades, the preserved 150-million-year-old remains of a dinosaur called Archaeopteryx defined a critical early moment in the evolution of modern birds.

Now, researchers aren't so sure, finding the famously feathered creature has more in common with a group called Deinonychosauria than Avialae. With few other convincing bird-like fossils from this time, researchers can only guess at what such an early bird might have looked like. Appearing just a few million years after Archaeopteryx, Fujianvenator might have at least a few answers, straddling the line between ancient dinosaur and more modern birds. The pelvis of Fujianvenator has features that are more similar to the less-bird-like dinosaurs, including the strange four-winged Anchiornis. This means that the morphological transition from arms to wings started really early on in bird ancestors, while legs were still doing different things, and suggests Fujianvenator branched off in a different direction than the one that led to birds.

This is the first time a potential swamp avialan has been identified. All the other avialans paleontologists have discovered so far have features of being tree dwellers.

https://www.nature.com/articles/s41586-023-06513-7

Comment by Dr. Krishna Kumari Challa on September 13, 2023 at 8:50am

Breast cancer recurrence may be triggered by chemotherapy injury to non-cancer cells

A standard chemotherapy drug injures surrounding non-cancer cells, which can then awaken dormant cancer cells and promotes cancer growth, according to a new study published September 12 in the open access journal PLoS Biology. The finding is important for understanding cancer recurrence and may point to important new targets to prevent it.

Advances in cancer treatment, including chemotherapy, have dramatically reduced mortality for many types of cancer, including breast cancer. Nonetheless, up to 23% of breast cancer patients experience recurrence within the first five years. Treatment is meant to kill all cancer cells, but often, some cells enter a state of dormancy, in which they stop dividing and become unresponsive to chemotherapeutic agents. Recurrence occurs when dormant cells re-awaken and start dividing again.

Some studies have indicated that chemotherapy itself may promote escape from dormancy, but the mechanism of this effect has not been clear.

To explore that question, the authors worked with both a cell model and a mouse model of breast cancer. Importantly, the cell model contained both cancer cells and non-cancer stromal cells, connective tissue cells that are found in breast and other tissue. They administered the chemotherapy drug docetaxel at physiologically relevant concentrations, and found that even at very low doses, stromal cells were injured, while cancer cells were not, and that treatment induced cell-cycle reentry in cancer cells.

The driver of this reawakening of dormant cells, the authors showed, was release of two key cell signaling molecules, granulocyte colony stimulating factor (G-CSF) and interleukin-6 (IL-6) by the injured stromal cells, which acted on the dormant cells to promote their growth, both in vitro and in vivo.

That provided the team with potential anti-cancer targets, and they showed that antibodies that neutralized either G-CSF or IL-6, or a drug that blocked the mediator of those signals within cancer cells, inhibited awakening from dormancy due to docetaxel treatment.

These findings have several important implications. First, they highlight the importance of surrounding cells, not just the cancer cells themselves, in determining the response to chemotherapy. Second, they provide a possible mechanistic foundation for the observation that high serum levels of IL-6 are associated with early recurrence in breast cancer patients receiving chemotherapy, potentially strengthening the utility of that biomarker in planning treatment. Third, they provide new targets for preventing recurrence.

Ganesan R, Bhasin SS, Bakhtiary M, Krishnan U, Cheemarla NR, Thomas BE, et al. (2023) Taxane chemotherapy induces stromal injury that leads to breast cancer dormancy escape. PLoS Biology (2023). DOI: 10.1371/journal.pbio.3002275

Comment by Dr. Krishna Kumari Challa on September 12, 2023 at 12:12pm

Bioengineered E. coli generates electricity from wastewater

In a breakthrough for the field of bioelectronics, researchers  have enhanced the ability of E. coli bacteria to generate electricity. The innovative approach offers a sustainable solution for organic waste processing while outperforming previous state-of-the-art technologies, opening new horizons for versatile microbial electricity production.

E. coli bacteria, a staple of biological research, have been harnessed to create electricity through a process known as extracellular electron transfer (EET). The  researchers engineered E. coli bacteria to exhibit enhanced EET, making them highly efficient "electric microbes." Unlike previous methods that required specific chemicals for electricity generation, the bioengineered E. coli can produce electricity while metabolizing a variety of organic substrates.

. By integrating components from Shewanella oneidensis MR-1, a bacterium famous for generating electricity, the researchers successfully constructed an optimized pathway that spans the inner and outer membranes of the cell. This novel pathway surpassed previous partial approaches, and led to a three-fold increase in electrical current generation compared to conventional strategies.

Importantly, the engineered E. coli exhibited remarkable performance in various environments, including wastewater collected from a brewery. While exotic electric microbes faltered, the modified E. coli thrived, showcasing its potential for large-scale waste treatment and energy production.

The implications of the study extend beyond waste treatment. Being able to generate electricity from a wide range of sources, the engineered E. coli can be utilized in microbial fuel cells, electrosynthesis, and biosensing—to name a few applications. In addition, the bacterium's genetic flexibility means that it can be tailored to adapt to specific environments and feedstocks, making it a versatile tool for sustainable technology development.

Mohammed Mouhib, Melania Reggente, Lin Li, Nils Schuergers, Ardemis A. Boghossian. Extracellular electron transfer pathways to enhance the electroactivity of modified Escherichia coli. Joule, 2023; DOI: 10.1016/j.joule.2023.08.006

Comment by Dr. Krishna Kumari Challa on September 12, 2023 at 10:01am

Researchers create optical device that can kill pathogens on surfaces while remaining safe for humans

While it has long been known that ultraviolet (UV) light can help kill disease-causing pathogens, the COVID-19 pandemic has put a spotlight on how these technologies can rid environments of germs. However, the excimer lamps and LEDs that can directly emit light in the required deep-UV wavelengths generally have low efficiency or suffer from short lifetimes. Moreover, UV light of the wrong wavelength can actually be harmful to human cells.

Now, researchers  have shown how an optical device made of aluminum nitride can be used to generate deep-UV light in a method wholly different from previous approaches. The team made use of a process called "second harmonic generation," which relies on the fact that the frequency of a photon, or particle of light, is proportional to its energy. The study is published in the journal Applied Physics Express.

Most transparent materials are considered "linear" with respect to their response to light, i.e., photons cannot interact with each other. However, inside certain "nonlinear" materials, two photons can be combined into a single photon with twice the energy, and thus, twice the frequency. In this case, two visible photons can be merged into a single deep-UV photon inside an aluminum nitride waveguide less than one micron wide. A waveguide is a channel of transparent material with physical dimensions chosen so that light of desired frequencies can travel easily. The waveguide helps take advantage of the nonlinear optical properties of the material, so that second harmonic generation can occur with the highest efficiency.

The wavelength of UV light created by the prototype device is within a very narrow range that has enough energy to kill germs but remains mostly harmless to humans.

 Hiroto Honda et al, 229 nm far-ultraviolet second harmonic generation in a vertical polarity inverted AlN bilayer channel waveguide, Applied Physics Express (2023). DOI: 10.35848/1882-0786/acda79

Comment by Dr. Krishna Kumari Challa on September 12, 2023 at 9:05am

Increasing severe maternal morbidity linked to heat exposure

Research provides strong evidence linking maternal heat exposure during pregnancy to an increased risk of severe maternal morbidity, with potential implications for public health strategies and interventions.

In a paper, "Analysis of Heat Exposure During Pregnancy and Severe Maternal Morbidity," published in JAMA Network Open, researchers explored the potential association between maternal environmental heat exposure and severe maternal morbidity (SMM).

The study included 403,602 pregnancies, with a mean age of 30.3 years, with data collected from Kaiser Permanente Southern California, a large integrated health care organization. Within the cohort, there were 3,446 cases of SMM (0.9%) over 10 years (2008 to 2018). Temperature values during pregnancy were assigned to individuals based on their geocoded home addresses.

Long-term heat exposure was measured by the proportions of heat days during pregnancy, categorized as moderate, high, and extreme heat days. The study observed significant associations between long-term heat exposure during pregnancy and SMM, particularly related to environmental heat exposure in the third trimester.

Short-term heat wave exposure during the last gestational week was assessed using nine different heat wave definitions based on temperature thresholds and durations. Short-term associations were significant under different heat wave definitions. The magnitude of associations generally increased from the least severe to the most severe heat wave exposure, with more significant associations observed with more severe heat exposure.

According to the Centers for Disease Control and Prevention, SMM "...includes unexpected outcomes of labor and delivery that result in significant short- or long-term consequences to a woman's health. Using the most recent list of indicators, SMM has been steadily increasing in recent years."

The researchers found an association between when pregnancies begin (the season of conception) and severe maternal morbidity (SMM). The authors mention that mothers who started pregnancy in the cold season (November through April) were more vulnerable to heat exposure and had higher associations between heat exposure and SMM compared to those who started pregnancy in the warm season (May to October).

This suggests that the timing of conception, leading to the stage of pregnancy during the hottest months, may influence the relationship between heat exposure and SMM.

The study concludes that both long-term and short-term maternal heat exposure during pregnancy is associated with a higher risk of severe maternal morbidity. These results have important implications for SMM prevention, especially considering climate change's current and future impacts.

The study also highlights the health disparities among mothers with different education levels. This suggests the need for targeted interventions to reduce SMM risk, particularly among mothers with low socioeconomic status.

Anqi Jiao et al, Analysis of Heat Exposure During Pregnancy and Severe Maternal Morbidity, JAMA Network Open (2023). DOI: 10.1001/jamanetworkopen.2023.32780

Comment by Dr. Krishna Kumari Challa on September 12, 2023 at 9:01am

What is maternal morbidity?

The World Health Organization defines maternal morbidity as any health condition attributed to and/or aggravated by pregnancy and childbirth that has negative outcomes to the woman’s well-being.

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