Comment

Comment by Dr. Krishna Kumari Challa on June 2, 2023 at 9:20am

The lead risk variant at the MTHFR–CLCN6 locus has been previously associated with reduced levels of circulating N-terminal pro-BNP43. A recent analysis found that first-trimester levels of N-terminal pro-BNP were unexpectedly lower among female individuals who subsequently developed hypertensive disorders of pregnancy later in pregnancy. These findings suggest that genetic network-driven deficiency in endogenous natriuretic peptide signaling may predispose individuals to hypertensive disorders of pregnancy.

Synthetic natriuretic peptides have been developed, and the authors suggest that natriuretic peptides may represent a future therapeutic target for direct or indirect modulation toward hypertensive disorders of pregnancy prevention and treatment.

 Michael C. Honigberg et al, Polygenic prediction of preeclampsia and gestational hypertension, Nature Medicine (2023). DOI: 10.1038/s41591-023-02374-9

Part 2

Comment by Dr. Krishna Kumari Challa on June 2, 2023 at 9:20am

From genes to gestation, researchers probe predictive markers for pregnancy complications

A new study has identified genetic markers associated with preeclampsia and gestational hypertension in a large cohort study. In the paper, "Polygenic prediction of preeclampsia and gestational hypertension," published in Nature Medicine, the researchers detail how these genetic markers could be used as a predictive risk assessment and offers mechanistic insights into pregnancy disorders.

Preeclampsia and gestational hypertension are common pregnancy complications associated with adverse outcomes, including substantial morbidity and mortality for both mother and child. Current tools for prediction, prevention and treatment are limited.

The team examined the associations of maternal DNA variants in 20,064 preeclampsia cases compared to 703,117 control individuals and gestational hypertension in 11,027 cases compared with 412,788 controls. Polygenic risk scores were tuned to a UK Biobank and then tested against other data sets for validation.

The analysis identified 18 independent loci associated with preeclampsia and gestational hypertension, 12 of which were previously unknown, and an additional two genes were implicated in a follow-up meta-analysis. The genes associated highlight potential roles of natriuretic peptide signaling, angiogenesis, renal glomerular function, trophoblast development and immune dysregulation.

Interestingly, almost none of the associated genes reside on the same chromosome, making them less likely to be inherited together.

Low-dose aspirin starting after week 12 gestation is an evidence-based but underused strategy to reduce risk of preeclampsia. To probe the potential clinical impact of incorporating PRS to guide aspirin allocation, researchers examined aspirin eligibility according to current US Preventive Service Task Force major criteria. Those with polygenic risk scores in the top 10% were shown to increase identification as low-dose aspirin-eligible by 30.4%, offering a potential preemptive intervention.

Part 1

Comment by Dr. Krishna Kumari Challa on June 1, 2023 at 10:16am

Darker skies are disappearing:

Light pollution can have negative consequences for the well-being of many living things—plants, animals and even humans. Between 2011 and 2022 light pollution increased globally by 9.6 percent a year. “This might not sound like much, but it reflects an exponential growth rate,” writes Phil Plait, astronomer and science communicator. 

Why this matters: Light pollution disrupts the migrations of birds, the blossoming of flowers and even the courtship of fireflies. For humans, more light might mean more insomnia or other health impacts. 

What the experts say: To help, you can: Use smarter streetlights that concentrate light downward (which are cheaper, too); turn off your own outdoor lighting at night; use targeted illumination rather than flood lighting; choose lightbulbs and LEDs that shine more red than blue to reduce how much light scatters across the sky. 

Comment by Dr. Krishna Kumari Challa on June 1, 2023 at 9:35am

Biological cleanup discovered for certain 'forever chemicals'

Chemical and environmental engineering scientists have identified two species of bacteria found in soil that break down a class of stubborn "forever chemicals," giving hope for low-cost biological cleanup of industrial pollutants.

These bacteria destroy a subgroup of per- and poly-fluoroalkyl substances, or PFAS, that have one or more chlorine atoms within their chemical structure.

Unhealthful forever chemicals persist in the environment for decades or much longer because of their unusually strong carbon-to-fluorine bonds. Remarkably, the researchers found that the bacteria cleave the pollutant's chlorine-carbon bonds, which starts a chain of reactions that destroy the forever chemical structures, rendering them harmless.

What they discovered is that bacteria can do carbon-chlorine bond cleavage first, generating unstable intermediates. And then those unstable intermediates undergo spontaneous defluorination, which is the cleavage of the carbon-fluorine bond.

Bosen Jin et al, Substantial defluorination of polychlorofluorocarboxylic acids triggered by anaerobic microbial hydrolytic dechlorination, Nature Water (2023). DOI: 10.1038/s44221-023-00077-6

Comment by Dr. Krishna Kumari Challa on June 1, 2023 at 9:32am

Scientists' report world's first X-ray of a single atom

A team of scientists has taken the world's first X-ray SIGNAL (or SIGNATURE) of just one atom. This groundbreaking achievement could revolutionize the way scientists detect the materials.

An important usage of X-rays in science is to identify the type of materials in a sample. Over the years, the quantity of materials in a sample required for X-ray detection has been greatly reduced thanks to the development of synchrotron X-rays sources and new instruments. To date, the smallest amount one can X-ray a sample is in attogram, that is about 10,000 atoms or more. This is due to the X-ray signal produced by an atom being extremely weak so that the conventional X-ray detectors cannot be used to detect it. It is a long-standing dream of scientists to X-ray just one atom, which is now being realized by the research team .

Atoms can be routinely imaged with scanning probe microscopes, but without X-rays one cannot tell what they are made of. Scientists can now detect exactly the type of a particular atom, one atom-at-a-time, and can simultaneously measure its chemical state.

Once they are able to do that, they can trace the materials down to ultimate limit of just one atom. This will have a great impact on environmental and medical sciences and maybe even find a cure that can have a huge impact for humankind. This discovery will transform the world.

Saw-Wai Hla, Characterization of just one atom using synchrotron X-rays, Nature (2023). DOI: 10.1038/s41586-023-06011-w. www.nature.com/articles/s41586-023-06011-w

Comment by Dr. Krishna Kumari Challa on June 1, 2023 at 9:26am

Sleep deprivation is a risk factor for Alzheimer's, say scientists

Scientists have long explored the link between disturbances in sleep patterns and neurodegenerative diseases. Powerful evidence has emerged in recent years linking disrupted sleep to Parkinson's, and a massive body of research has explored the serious sleep disturbances associated with chronic traumatic encephalopathy—CTE—a condition linked with repeated head injuries, such as the trauma sustained in boxing, football and other aggressive sports.

Of equal concern has been sleep impairments associated with Alzheimer's disease, a condition that is increasing globally as the world's population inexorably ages. According to data from the Mayo Clinic, an estimated 25% of people with mild to moderate forms of the disorder have disturbed sleep and 50% are estimated to have sleep problems when the condition is deemed severe.

Now, scientists have posed a series of provocative questions about the impact of poor sleep and the development of Alzheimer's disease. Chronic sleep disturbances, these scientists say, are an inescapable Alzheimer's risk factor.

The scientists have also demonstrated in a series of experiments that sleep deprivation prevents immune cells known as microglia from properly cleaning up deposits of amyloid protein during the sleep cycle, a finding that helps explain the long-observed connection between sleep loss and neurodegeneration. Amyloid proteins are the building blocks of gooey amyloid plaques, a key hallmark of Alzheimer's disease.

In their research, which is reported in Science Translational Medicine, the team turned to multiple mouse models to show how disrupted sleep patterns allow deposits of amyloid to accumulate. Sleep is biologically beneficial to the brain because that's when an elaborate network flushes away excess amyloid as well as cellular and metabolic debris. Without that daily clean-up cycle, the brain can pay an enormous price, according to these scientists.

These findings highlight that sleep deprivation directly affects microglial reactivity, for which TREM2 is required, by altering the metabolic ability to cope with the energy demands of prolonged wakefulness, leading to further amyloid-β deposition, and underlines the importance of sleep modulation as a promising future therapeutic approach.

Samira Parhizkar et al, Sleep deprivation exacerbates microglial reactivity and Aβ deposition in a TREM2 -dependent manner in mice, Science Translational Medicine (2023). DOI: 10.1126/scitranslmed.ade6285

Comment by Dr. Krishna Kumari Challa on June 1, 2023 at 8:26am

When researchers analyzed the data they collected, they found that there was a relationship between the patients' olfactory responses and their levels of consciousness. They also found that patients in the no-olfactory responses group showed higher theta functional connectivity than patients in the olfactory response group after they were presented with the vanillin scent, and lower alpha and beta relative powers than healthy participants with no DoC.

The follow-up data collected three months later showed that 10 out of 16 of the patients who responded to olfactory stimuli during the study had recovered consciousness, while only 2 out of the 12 participants who did not respond to olfactory stimuli did. This suggests that a brain response to olfactory stimuli is typically a sign that patients with DoC are gradually recovering and regaining consciousness.
Olfactory responses should be considered signs of consciousness," teh researchers explained in their paper. "The differences in olfactory processing between DoC patients with and without olfactory responses may be a way to explore the neural correlates of olfactory consciousness in these patients. The olfactory response may help in the assessment of consciousness and may contribute to therapeutic orientation."

Wanchun Wu et al, Olfactory response is a potential sign of consciousness: electroencephalogram findings, Frontiers in Neuroscience (2023). DOI: 10.3389/fnins.2023.1187471.

Part 2

Comment by Dr. Krishna Kumari Challa on June 1, 2023 at 8:24am

The olfactory responses of patients in a coma or vegetative state can display different signs of consciousness

Severe brain injuries or head traumas in humans can lead to various stages of so-called disorders of consciousness (DoC). These are states in which consciousness is either partly or entirely absent, such as a coma; unresponsive wakefulness syndrome, also known as a vegetative state; and minimally conscious state.

Accurately evaluating patients who have lost consciousness is of crucial importance, as it allows doctors to determine what treatments to administer and how to facilitate the re-emergence of consciousness. Typically, to clinically evaluate consciousness, doctors observe the behavior of patients in response to sensory stimuli, such as sounds or images.

For instance, while patients in a vegetative state are awake but continue to be unresponsive to external stimuli, patients with MCS exhibit some behaviors that indicate that they are conscious. So far, most methods to assess the consciousness level of patients rely on sounds or visual stimuli, yet olfactory stimuli could potentially prove useful too.

Researchers recently carried out a study investigating the responses of patients in a coma or vegetative state to smells, to understand whether they could be used to evaluate consciousness. Their findings, published in Frontiers in Neuroscience, appear to highlight the potential of olfactory stimuli for assessing consciousness in clinical settings.

This study aimed to explore whether olfactory response can be a sign of consciousness and represent higher cognitive processing in patients with disorders of consciousness (DoC) using clinical and electroencephalogram data.

As part of their study, the researchers evaluated the responses of 28 patients at different stages of DoC to olfactory stimuli. Out of these patients, 13 were in a vegetative state (UMS) and 15 in MCS. The study participants were divided into two groups based on whether they responded to olfactory stimuli or not. After three months, the outcomes of DoC patients were followed up using the coma recovery scale-revised (CRS-R)" [i.e., a standard assessment used to measure DoC in clinical settings].
Part 1

Comment by Dr. Krishna Kumari Challa on May 31, 2023 at 12:00pm

How the humble neutron can help solve some of the universe's deepest mysteries

Scientists are unleashing the power of neutrons to improve understanding of everyday materials and tackle fundamental questions in physics.

Chemistry looks at the building blocks of our physical world, such as atoms, and the changes they undergo. An atom consists of a nucleus of protons and neutrons surrounded by a cloud of electrons.

 The humble neutron, found in the nucleus of every atom but hydrogen, can—if manipulated in just the right way—shed light on everything from the climate crisis and energy, to health and quantum computing.

One such way is a rather spectacular process known as spallation, high energy particles destabilize an atom's nucleus, which in turn releases some of the neutrons found there.

When harnessed, these newly freed neutrons can be used like X-rays to map the inner structure of materials.

Currently under construction in Lund, Sweden, the European Spallation Source (ESS) is expected to come online in 2027. Once it achieves its full specifications, its unprecedented flux and spectral range is set to make it the most powerful and versatile neutron source for science in the world.

The purpose of the facility "is to create neutrons, a neutron beam, to be used for scientific purposes."

Once the facility is up and running, scientists from across Europe and the rest of the world will be able to use its 15 different beamlines to conduct fundamental research. 

a neutron beam "is not the same as an X-ray, but it is complementary and uses some of the same physical laws."

Like X-rays, neutrons can be used to probe materials and biological systems. But they interact with materials in different ways to the photons in high-energy X-ray beams, and therefore provide different types of information about their targets.

For example, neutron beams can say something about the interior dynamics of lithium-ion batteries, reveal obscured details from ancient artifacts or clarify the mechanisms of antibiotic resistance in bacteria. They can also be used to explore fundamental physics. It almost seems like a case of "what can't they do?"

https://cordis.europa.eu/project/id/823867

https://cordis.europa.eu/project/id/951782

https://research-and-innovation.ec.europa.eu/funding/funding-opport...

https://phys.org/news/2023-05-humble-neutron-universe-deepest-myste...

Comment by Dr. Krishna Kumari Challa on May 31, 2023 at 11:38am

New high resolution X-ray imaging technique can image biological specimens without causing damage

A pollen grain showing the nanofoam within or a diatom with the individual geometric structures inside clearly visible: Using high-energy X-rays from the PETRA III synchrotron light source at DESY, a team of scientists has managed to image these structures without damaging them.

Their new technique generates high resolution X-ray images of dried biological material that has not been frozen, coated, or otherwise altered beforehand—all with little to no damage to the sample. This method, which is also used for airport baggage scanning, can generate images of the material at nanometre resolution.

Using high energy X-rays that are intensely focused through a set of novel diffractive lenses, the special technique allows imaging to be performed at less than 1% of the X-ray damage threshold of the specimen. The results, which reveal this method as a promising tool for brighter next-generation light sources such as the planned upgrade project PETRA IV, have been published in the journal Light: Science & Applications.

X-ray light interacts with biological material in a variety of ways, mostly depending on the energy and intensity of the light. At the same time, radiation damage, such as small structural changes up to complete degradation of the sample, is the limiting factor during X-ray imaging of biological samples.

At low energies, the X-rays are primarily absorbed by the atoms in the sample, whose electrons take on the energy, causing them to spring out of the atoms and cause damage to the sample. Images using these low-energy X-rays thus map out the sample's absorption of the radiation. At higher energies, absorption is less likely, and a process called elastic scattering occurs, where the X-ray photons "bounce" off of the matter like billiard balls without depositing their energy.

Techniques such as crystallography or ptychography use this interaction. Nevertheless, absorption can still occur, meaning damage to the sample happens anyway. But there is a third interaction: Compton scattering, where the X-rays leave only a tiny amount of their energy in the target material. Compton scattering had been largely ignored as a viable method of X-ray microscopy, since it requires even higher X-ray energies where until now no suitable high-resolution lenses existed.

Tang Li et al, Dose-efficient scanning Compton X-ray microscopy, Light: Science & Applications (2023). DOI: 10.1038/s41377-023-01176-5

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