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Comment by Dr. Krishna Kumari Challa on June 8, 2023 at 12:18pm

'AI doctor' better at predicting patient outcomes, including death

Artificial intelligence has proven itself useful in reading medical imaging and even shown it can pass doctors' licensing exams.

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Food safety: Cleaning with plasma instead of chemicals

A new method for cleaning conveyor belts in food production can replace the widely used disinfection chemicals. Plasma-treated water is effective against microbial contamination at a shorter exposure time and degrades without environmentally hazardous traces. These results were recently published in the journal Innovative Food Science and Emerging Technologies.

Comment by Dr. Krishna Kumari Challa on June 8, 2023 at 11:47am

How an earthquake becomes a tsunami

The movement between continental and oceanic plates at the bottom of the sea, so-called megathrust earthquakes, generates the strongest tremors and the most dangerous tsunamis. How and when they occur, however, has been poorly understood so far, since the ocean floor is difficult to access for measurements.

Thanks to new technologies, an international research team was able to take measurements to the nearest centimeter for the first time in an underwater-earthquake zone off Alaska. The researchers reported on their findings in the specialist journal Science Advances.

The Chignik earthquake on July 28, 2021, occurred 32 km below the seafloor off the coast of Alaska and, with a magnitude of 8.2, was the seventh strongest earthquake in US history. It occurred because the oceanic Pacific Plate is sliding past the continental North American Plate, thereby causing an enormous thrust.

In the sparsely populated region, the damage caused by the quake was limited. In general, however, such megathrust earthquakes have enormous destructive potential in the so-called subduction zone, i.e. the zone where oceanic and continental tectonic plates meet. In particular, tsunami waves can be generated. These are not very high at their place of origin, but hours later and many 100 or 1000 kilometers away, they can hit the coasts as a catastrophic tsunami and endanger many lives.

Researchers examined the seafloor off Alaska shortly before and about 2.5 months after the Chignik quake, using a global navigation satellite system (GNSS), an acoustic positioning system, and a robotic ship.

In the project, a key role was played by autonomous vessels , called wave gliders, that operate on the water surface.

The modern technology allowed measurements of the movements in the subduction zones to the nearest centimeter and thus a precise picture of the complicated slip processes and faults. Particular attention was paid to the shallow portions of the slip zones, as these are critical to whether or not a tsunami will occur. The measurements were taken at a water depth of 1,000 to 2,000 meters.

Benjamin A. Brooks et al, Rapid shallow megathrust afterslip from the 2021 M8.2 Chignik, Alaska earthquake revealed by seafloor geodesy, Science Advances (2023). DOI: 10.1126/sciadv.adf9299

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Comment by Dr. Krishna Kumari Challa on June 8, 2023 at 11:15am

Remains of an extinct world of organisms discovered

Newly discovered biomarker signatures point to a whole range of previously unknown organisms that dominated complex life on Earth about a billion years ago. They differed from complex eukaryotic life as we know it, such as animals, plants and algae in their cell structure and likely metabolism, which was adapted to a world that had far less oxygen in the atmosphere than today.

An international team of  researchers now reports on this breakthrough for the field of evolutionary geobiology in the journal Nature.

The previously unknown "protosteroids" were shown to be surprisingly abundant throughout Earth's Middle Ages. The primordial molecules were produced at an earlier stage of eukaryotic complexity—extending the current record of fossil steroids beyond 800 and up to 1,600 million years ago. Eukaryotes is the term for a kingdom of life including all animals, plants and algae and set apart from bacteria by having a complex cell structure that includes a nucleus, as well as a more complex molecular machinery.

This "stem" represents the common ancestral lineage that was a precursor to all still living branches of eukaryotes. Its representatives are long extinct, yet details of their nature may shed more light on the conditions surrounding the evolution of complex life.

Although more research is needed to evaluate what percentage of protosteroids may have had a rare bacterial source, the discovery of these new molecules not only reconciles the geological record of traditional fossils with that of fossil lipid molecules, but yields a rare and unprecedented glimpse of a lost world of ancient life.

The competitive demise of stem group eukaryotes, marked by the first appearance of modern fossil steroids some 800 Million years ago, may reflect one of the most incisive events in the evolution of increasingly complex life.

Jochen Brocks, Lost world of complex life and the late rise of the eukaryotic crown, Nature (2023). DOI: 10.1038/s41586-023-06170-w. www.nature.com/articles/s41586-023-06170-w

Comment by Dr. Krishna Kumari Challa on June 8, 2023 at 10:27am

A documented case of a crocodile virgin birth

A team of entomologists and reptile specialists from Virginia Polytechnic Institute and State University, the Chiricahua Desert Museum, the Illinois Natural History Survey, Reptilandia Reptile Lagoon and Parque Reptilandia has documented a case of a virgin crocodile laying viable eggs. In their paper published in the journal Biology Letters, the group describes their surprise at the discovery of a clutch of eggs laid by an American crocodile who had been kept alone in an enclosure at Parque Reptilandia park in Costa Rica for 16 years prior to laying the eggs.

Prior research has found instances of "virgin birth"—a type of asexual reproduction in a species that normally reproduces sexually—in snakes, lizards, sharks and birds, but never in Crocodilia, an order that includes gharials, caimans, alligators and crocodiles. So the handlers at Parque Reptilandia were surprised to see a clutch of eggs in an enclosure hosting a single American crocodile.

Alligators are well known in North America, but crocodiles live there, too, in parts of Florida. They also live in Central and South America. They normally mate to reproduce, like most other reptiles, and lay eggs that later hatch. But now, it appears that they can reproduce asexually if need be.

The clutch of 14 eggs was discovered back in 2016. After handlers noted their arrival, they notified local specialists. The eggs were collected and taken to a lab for study, where researchers found that half of them were viable. The viable eggs were placed in an incubator with the hope of producing hatchlings.

None of the eggs produced any, unfortunately, leading the researchers to crack them open after three months to see what was going on. All of the eggs had progressed toward hatching, but only one actually resembled a fetus. A genetic study of the most advanced specimen revealed that it was nearly identical to its mother.

The research team notes that it was not surprising that none of the eggs were hatchable; eggs laid in such fashion rarely are. Now that virgin births have been documented in both birds and Crocodilia, it raises the question of whether pterosaurs and/or dinosaurs were able to do so, as well.

 Warren Booth et al, Discovery of facultative parthenogenesis in a new world crocodile, Biology Letters (2023). DOI: 10.1098/rsbl.2023.0129

Comment by Dr. Krishna Kumari Challa on June 8, 2023 at 10:06am

Synthetic species created without biochemistry operate according to Darwinian evolutionary principles

Imagine the possibility of life forms on other planets that don't resemble any on Earth. What might they look like, and why would they be so different?

This may be possible and the answer may be that they developed from a different type of chemistry.

Some researchers have studied how to produce synthetic living systems—without relying on biochemistry, or the chemistry that has enabled life on Earth. They have been have been trying to build a non-biochemical system, which unaided is capable of executing the essential properties common to all natural living systems. 

  One latest study, published last month in Cell Reports Physical Science, even finds such a system engaged in what Charles Darwin called "the struggle for life.

Researchers   created two synthetic models (or "species") and observed the ensuing competition between them. They figured out how to create non-biochemical but carbon-chemistry-based systems called protocells. These are made up of self-assembling polymer vesicles that emerge from a homogenous blend of smaller synthetic chemicals with no relation to living organisms. "These systems act like biochemical cells. They are born, metabolize what they need, grow, move, reproduce, and perhaps even evolve.

Now the researchers wanted to see whether these systems would operate according to the evolutionary principle of competitive exclusion. As we know from Darwin's work, this involves the struggle for survival—with the species with the greatest competitive advantage edging out the other when vying for resources.

They created two new species of protocells for this particular study—one with the advantage of light sensitivity, the other without. When the researchers watched how these systems behaved as they shared food in an illuminated environment, they saw that the light-sensitive "species" endured while the other did not. "It's the struggle for existence where the best-suited structure survived in its environment.

With these results, these researchers are  willing to go as far as to suggest that biochemicals are not essential to the struggle for life. This shows that non-biochemical carbon chemistry can lead to the extinction of the less 'fit' protocell species. 

Could there be chemistries beyond Earth capable of implementing the fundamental properties of life?

It's possible there are materials, which once on a planetary surface somewhere with appropriate conditions, could react chemically, self-organize, and perhaps do the things that this experiment shows.

Under the right circumstances, these materials may evolve from very simple chemistry into more complicated structures.

So these scientists think we should be very open about other forms of life elsewhere in the universe, and that they may not resemble life as we recognize it now.

Sai Krishna Katla et al, Competitive exclusion principle among synthetic non-biochemical protocells, Cell Reports Physical Science (2023). DOI: 10.1016/j.xcrp.2023.101359

Comment by Dr. Krishna Kumari Challa on June 7, 2023 at 11:49am

Data show no evidence that chronic disease treatment efficacies depend on number of comorbidities

Treatment efficacy for a broad range of chronic diseases does not differ depending on patients' comorbidities, according to a new study publishing June 6 in the open access journal PLOS Medicine.

There is often uncertainty about how treatments for single conditions should be applied to people who have multiple chronic conditions (multimorbidity). This confusion stems, in part, from the fact that people with multimorbidity are under-represented in randomized controlled trials, and trials rarely report whether the efficacy of treatment differs by the number of comorbidities or the presence of specific comorbidities.

In the new study, the researchers used existing data from 120 industry-sponsored randomized controlled phase 3 and 4 clinical trials carried out between 1990 and 2017. The dataset included a total of 128,331 participants and spanned 23 common long-term conditions, including asthma, diabetes, hypertension, osteoporosis, and migraine. For each trial as well as each treatment type spanning multiple trials, the team modeled whether there were any interactions between treatment efficacy and comorbidities.

Across trials, the percentage of participants with three or more comorbidities ranged from 2.3% (in allergic rhinitis trials) to 57% (in trials for systemic lupus erythematosus). Overall, the new study found no evidence of comorbidities modifying treatment efficacy across any of the 23 conditions studied. However, the authors noted that the trials were not designed to assess variation in treatment efficacy by comorbidity.

These findings suggest that for modest levels of comorbidities, this assumption is reasonable.

Hanlon P, Butterly EW, Shah AS, Hannigan LJ, Lewsey J, Mair FS, et al. Treatment effect modification due to comorbidity: Individual participant data meta-analyses of 120 randomised controlled trials, PLoS Medicine (2023). DOI: 10.1371/journal.pmed.1004176

Comment by Dr. Krishna Kumari Challa on June 7, 2023 at 9:12am

Ants inflict pain with neurotoxins

Researchers have shown for the first time that some of the world's most painful ant stings target nerves, like snake and scorpion venom. This research is published in Nature Communications.

Investigators discovered the ant neurotoxins while studying the Australian green ant and South American bullet ant which have stings that cause long-lasting pain.

These ant venoms target our nerve cells that send pain signals. Normally, the sodium channels in these sensory neurons open only briefly in response to a stimulus. However,  the ant toxins bind to the sodium channels and cause them to open more easily and stay open and active, which translates to a long-lasting pain signal.

Bullet ant stings can be painful for up to 12 hours and it's a deep drilling pain you feel in your bones with sweating and goosebumps, quite unlike the 10-minute impact of a typical bee sting.

The bullet ant was rated as having the most painful insect sting in the world by the late Dr. Justin Schmidt, an American entomologist who created a pain index of stinging insects.

These neurotoxins which target sodium channels are unique to ants. Ants developed their defensive neurotoxins to fend off predators during the time of the dinosaurs and have since become one of the most successful animal groups on Earth..

Samuel D. Robinson et al, Ant venoms contain vertebrate-selective pain-causing sodium channel toxins, Nature Communications (2023). DOI: 10.1038/s41467-023-38839-1

Comment by Dr. Krishna Kumari Challa on June 7, 2023 at 9:01am

In this way, the researchers in the present analysis summarized multiple methods of interventional wound care and detailed their mechanisms-of-action in preclinical and clinical environments to treat acute and chronic wounds. These methods focus on highly diverse phases of wound healing, including tight closure of the wound to establish homeostasis and modulate the immune system during inflammation, and cell proliferation alongside remodeling in the area of intervention. The bioengineers and materials scientists hope that future wound dressings may sense the unique environment of an inflicted region to deliver personalized strategies to autonomously regulate drug doses for every patient.

As a strategic plan-of-work for bioengineers, the researchers suggest developing an evidence-based target profile and patenting strategy to effectively translate new wound care products from the bench to the bedside in health care. The industrial translation of standard care requires strong clinical data for emerging methods to survive beyond the bench and positively influence the quality of life of patients.

 Benjamin R. Freedman et al, Breakthrough treatments for accelerated wound healing, Science Advances (2023). DOI: 10.1126/sciadv.ade7007

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Part 3

Comment by Dr. Krishna Kumari Challa on June 7, 2023 at 9:00am

The researchers listed the principles of open wound management as follows:

Moisture balance
Infection prevention
Medical optimization of comorbidities including vascular disease and blood glucose control
They discussed the possibilities of minimizing inflammation, and progression towards active proliferation as a healing response. Several methods in the market aim to detect elevated protease activity for impaired wounds, and apply topical oxygen therapy and ultrasound therapy.
The study outcomes highlighted the need for additional strategies, including healing the chronic wounds at complex and intricate levels. Most advances in intervention target coordinated cellular processes to optimize wound care, however, such methods remain incompletely understood, requiring ongoing research innovations. Researchers described the primary aim of existing commercially available interventional biomaterials to impart fluid exudation, moisture balance, and pressure relief to prevent infection.

The advanced biomaterials in development for interventional healing can mimic extracellular matrix-inspired biophysical cues to regulate immune responses to treat and resolve inflammation. Such advances can be delivered to treat patients at the cellular level, where hydrogel influenced delivery systems can allow the sustained release of stimuli-responsive drug molecules to assist patients in adhering to new therapies. The outcomes can facilitate clinical trials of new drugs and biological products to therapeutically interfere in acute and chronic wounds.
Acute wounds arising from surgical and traumatic events can be treated with bandages to inhibit bleeding and effectively promote healing. Researchers have recently combined adhesive hydrogels with surgical meshes to demonstrate their strong adhesion and flexibility under mechanical stress. The present study described existing advanced wound therapies in the clinical pipeline for wound management, anti-infection and biological intervention. These include advanced anti-scarring and healing-promoting therapies. For example, a cell-penetrating asymmetric interfering RNA delivered as an intradermal injection can target connective tissue growth factor to combat scarring.

New peptide formulas engineered to treat venous leg ulcers and diabetic foot ulcers are currently in phase 1 and 2 clinical trials. Next-generation therapies to treat burns are also in clinical trials. For instance, commercially available NexoBrid is a topical agent made of enzymes isolated from a pineapple plant containing a few proteinases to provide selective and quick removal of damaged/dead tissues within hours of application. Phase 3 clinical trial outcomes have shown the impact of the topical agent on healing tissue areas of interest without adverse serious effects. Several cell-based therapies are also similarly under study for adequate intervention.
Part 2

Comment by Dr. Krishna Kumari Challa on June 7, 2023 at 8:59am

Breakthrough treatments for accelerated wound healing

Patients who undergo skin injuries endure hospital stays, infection and/or succumb to death; therefore, advances in wound healing aim to improve clinical practices underlying macroscale healing to effectively intervene in microscale pathophysiology. As a result, strategies that optimize wound healing have motivated the design of new therapeutic products.

In a new report in Science Advances, researchers summarized advances in the development of new drugs, biomaterial therapies and biological products suited for wound healing. They classified the products as marketed therapies and agents for clinical trials to explore their successful and accelerated translation for wound healing.

The dynamics of chronic wound healing mechanisms The timeframe of wound healing can vary and affect the process of patient recovery. Most wounds are classified as acute or chronic situations according to their clinical presentations. Untreated wounds can undergo cell death and necrosis, and represent ischemia relative to inadequate circulation due to microvascular damage and vasoconstriction. The nutritional status, fibroblast cell and progenitor health, as well as infectious bioburden, can contribute to disease progression.

Normal healing is associated with a series of events, including inflammation, remodeling and repair. Wounds that do not proceed through normal phases remain in a dysregulated inflammatory state with several delineating nuances.

For example, pressure ulcers result from an increasing depth of tissue necrosis and pain from microvascular injury causing ulceration and skin degradation to reach underlying fat or deeper structures. The resulting wounds require specialty care. Bioengineers and materials scientists in medical research have formed extensive libraries of wound care technologies to facilitate progressive healing.

Researchers observed the economic challenges of wound care on health care systems that showed an increasing risk in patients with age and obesity alongside those who presented with high-risk comorbidities. Surgical wounds are the largest wound subset, accounting for careful surgical techniques and optimal suture materials in hospitals. Existing standards for interventional healing rely on the preparation of a viable wound bed for assisted healing to remove foreign materials and ischemic tissue. More complex wounds require secondary healing or a bridge for closure. Pressure injuries represent a more serious problem in bedridden patients.

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