Comment

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.

Comment by Dr. Krishna Kumari Challa on September 10, 2023 at 12:11pm

Mysterious shiny orb seen on seafloor off Alaska

Using a robotic arm, the researchers gently nudged the object, determining that it was quite soft, before collecting it via suction for further study. DNA analysis will be conducted to pin down the organism responsible for its creation.

Comment by Dr. Krishna Kumari Challa on September 8, 2023 at 9:32am

Chitin from crustaceans, insects, mushrooms engages the immune system during digestion

Digesting a crunchy critter starts with the audible grinding of its rigid protective covering—the exoskeleton. Unpalatable as it may sound, the hard cover might be good for the metabolism, according to a new study in mice.

The researchers found in mice that digesting chitin, an abundant dietary fiber in insect exoskeletons and also mushrooms and crustacean shells, engages the immune system. An active immune response was linked to less weight gain, reduced body fat and a resistance to obesity. 

The researchers found that a particular arm of the immune system also is involved in chitin digestion. Stomach distention after chitin ingestion activates an innate immune response that triggers stomach cells to ramp up production of enzymes, known as chitinases, that break down chitin. Of note, chitin is insoluble—incapable of being dissolved in liquid—and thus requires enzymes and harsh acidic conditions to digest.

The study  results show that chitin activates immune responses in the absence of bacteria.

The stomach cells change their enzymatic output through a process we refer to as adaptation. But it is surprising that this process is happening without microbial input, because bacteria in the gastrointestinal tract are also sources of chitinases that degrade chitin.

The research team found that the greatest impact on obesity in mice occurred when chitin activated the immune system but was not digested. Mice fed a high fat diet also were given chitin. Some mice lacked the ability to produce chitinases to break down chitin. The mice that ate chitin but couldn't break it down gained the least amount of weight, had the lowest body fat measurements and resisted obesity, compared with mice that didn't eat chitin and with those that did but could break it down.

If the mice could break down chitin, they still benefited metabolically, but they adapted by overproducing chitinases to extract nutrients from chitin.

 Do-Hyun Kim et al, A type 2 immune circuit in the stomach controls mammalian adaptation to dietary chitin, Science (2023). DOI: 10.1126/science.add5649. www.science.org/doi/10.1126/science.add5649

Comment by Dr. Krishna Kumari Challa on September 8, 2023 at 9:24am

Device to monitor transplanted organs detects early signs of rejection

Researchers have developed the first electronic device for continuously monitoring the health of transplanted organs in real time.

Sitting directly on a transplanted kidney, the ultrathin, soft implant can detect temperature irregularities associated with inflammation and other body responses that arise with transplant rejection. Then, it alerts the patient or physician by wirelessly streaming data to a nearby smartphone or tablet.

In a new study, the researchers tested the device on a small animal model with transplanted kidneys and found the device detected warning signs of rejection up to three weeks earlier than current monitoring methods. This extra time could enable physicians to intervene sooner, improving patient outcomes and well-being as well as increasing the odds of preserving donated organs, which are increasingly precious due to rising demand amid an organ-shortage crisis.

Surabhi R. Madhvapathy et al, Implantable bioelectronic systems for early detection of kidney transplant rejection, Science (2023). DOI: 10.1126/science.adh7726. www.science.org/doi/10.1126/science.adh7726

Comment by Dr. Krishna Kumari Challa on September 7, 2023 at 3:06pm

India's Lunar Lander Has Detected 'Movement' on The Moon: But Is It Seismic Activity?

India's Chandrayaan-3 mission may have just recorded the first seismic data on the Moon since the 1970s. If confirmed to be natural seismic data, it could finally help scientists understand how the Moon's insides are arranged. The rumblings were recorded by the Vikram lander's onboard Instrument for Lunar Seismic Activity (ILSA). It's the first Micro Electro Mechanical Systems (MEMS) technology-based instrument on the Moon and it was was able to record the seismic rumbles of the mission's Pragyan rover moving around on the surface. But it also picked up what could be a natural event, such as a quake or an impact.

ILSA's primary objective is to measure ground vibrations generated by natural quakes, impacts, and artificial events. The vibrations recorded during the rover's navigation on August 25, 2023, are depicted in the figure," the Indian Space Research Organisation (ISRO) wrote in a statement.

Additionally, an event, seemingly natural, recorded on August 26, 2023, is also shown. The source of this event is currently under investigation.

This is tremendously exciting; to date, the best seismic data we have for the Moon was that collected by the Apollo program in the late 1960s and 1970s. Scientists have been itching to get their hands on more since we still don't know how the Moon's inner layers are arranged . Seismic data would go a long way to resolving that.

Even though it's only been a few weeks since ISRO landed on the Moon, it's already conducted a bunch of scientific observations and detected the first elements at the south pole.

Now both lander and rover are currently in sleep mode. That's because it's now night where they are on the Moon, which lasts 14 days or so.

Vikram and Pragyan, like other lunar missions before them, are solar powered, which means they "sleep" at night, when their batteries can't recharge.
Vikram and Pragyan will emerge from slumber on 22 September, when they will recommence their explorations of the mysterious south pole of the Moon.

Source: ISRO

Comment by Dr. Krishna Kumari Challa on September 7, 2023 at 2:59pm

What Was the First Animal to Evolve a Brain?

In the absence of a precise definition of brain, pinning down its origins is difficult. But scientists have a theory.

Having a brain is so necessary to human experience that it’s almost impossible to imagine any life without it. However, many living organisms don’t have brains, and going back far enough in time will lead to an ancestor of our own that was equally brainless. So, when exactly did brains evolve?

Scientists home in on the brain’s evolutionary origins by sorting out the animals without brains. Sponges have no neurons, so they are easy to discount, and while the more sophisticated jellyfish and sea anemones have a network of neurons, they have no central neural “headquarters” characteristic of a brain. 

About 600 million years ago, another group of animals evolved that had bilateral symmetry, meaning that they had a front and a back. “The front is where the nervous system crystallizes because that’s the bit of the animal that’s meeting the environment head on”. The first brain-like mass of neurons likely evolved at the front end of a long, thin, worm-like animal. Everything else that descended from that has a descendent of that neutral structure.

Today, there are many species, including some invertebrates such as the octopus, with brains that work similar to ours. These brains control perception, behaviour, and higher functions like memory. They are complex and wondrous, and they all evolved from a clump of neurons in the head of a worm.

Comment by Dr. Krishna Kumari Challa on September 7, 2023 at 2:50pm

Plant biology discovery is ‘like a switch between life and death’

Comment by Dr. Krishna Kumari Challa on September 7, 2023 at 12:49pm

Researchers issue warning over Chrome extensions that access private data

Google Chrome browser extensions expose users to hackers who can easily tap into their private data, including social security numbers, passwords and banking information, according to researchers at the University of Wisconsin-Madison (UW-M).

The researchers further uncovered vulnerabilities involving passwords that are stored in plain text within HTML source code on web sites of some of the world's largest corporate giants, including Google, Amazon, Citibank, Capital One and the Internal Revenue Service.

The problem stems from the manner in which extensions access internal web page code. 

Google offers thousands of extensions that users install to handle calendar events, password management, ad blocking, email access, bookmark storage, translation and search activities.

While such extensions help expand upon browser capabilities and make browsing easier, they also expose stored data to intruders.

In the absence of any protective measures, as seen on websites like IRS.gov, Capital One, USENIX, Google, and Amazon, sensitive data such as SSNs and credit card information are immediately accessible to all extensions running on the page. This presents a significant security risk, as private data is left vulnerable

The threat remains despite protective measures introduced by Google this year that have been embraced by most browsers. The protocol placed stricter limits on what kinds of information extensions can access.

But there remains no protective layer between web pages and browser extensions, so bad actors can still evade detection.

The researchers described "the alarming discovery" of passwords stored in plain text HTML web page source files.

A significant percentage of extensions possess the necessary permissions to exploit these vulnerabilities and researchers have  identified 190 extensions "that directly access password fields."

The extension faults stemmed from two key procedural violations in coding: least privilege and complete mediation.

Least privilege refers to the principle that users and systems should be granted only the lowest level of access privilege required to complete tasks. Any unnecessary privilege should be barred. Default access states should be on "deny" and not "allow."

Complete mediation refers to evaluation of each and every access request, with no deviations or exceptions.

Asmit Nayak et al, Exposing and Addressing Security Vulnerabilities in Browser Text Input Fields, arXiv (2023). DOI: 10.48550/arxiv.2308.16321

The researchers proposed two means to address the problem. The first is a JavaScript add-on for all extensions that provide solid cover for sensitive input fields.

The second proposal is to add a browser feature that alerts users when an attempt is made to access sensitive data.

Comment by Dr. Krishna Kumari Challa on September 6, 2023 at 11:55am

Microplastics from tires are polluting our waterways

Urban storm water particles from tire wear were the most prevalent microplastic a new  study has found. Published in Environmental Science & Technology, the study showed that in storm water runoff during rain approximately 19 out of every 20 microplastics collected were tire wear particles with anywhere from 2 to 59 particles per liter of water.

Pollution of our waterways by microplastics is an emerging environmental concern due to their persistence and accumulation in aquatic organisms and ecosystems.

Storm water runoff which contains a mixture of sediment, chemical, organic and physical pollutants, is a critical pathway for microplastics to washed off from urban environments during rain and into local aquatic habitats.

Tire rubber contains up to 2,500 chemicals with the contaminants that leach from tires considered more toxic to bacteria and microalgae than other plastic polymers.

Sediment samples collected from the inlet and outlet of a constructed storm water wetland contained between 1,450 to 4,740 particles in every kilogram of sediment, with more microplastics in the sediment at the inlet than the outlet, indicating the wetland's ability to remove them from storm water.

Microplastics that enter constructed wetlands for storm water drainage systems settle in the sediment and form a biofilm, leading to their accumulation over time, removing them from storm water runoff.

These  findings show that both constructed wetlands and the storm water capture device are strategies that could be potentially used to prevent or at least decrease the amount of microplastics tire wear particles being transported from storm water into our waterways.

Shima Ziajahromi et al, Microplastics and Tire Wear Particles in Urban Stormwater: Abundance, Characteristics, and Potential Mitigation Strategies, Environmental Science & Technology (2023). DOI: 10.1021/acs.est.3c03949

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