Science method – Scientific Library Mon, 15 Nov 2021 11:05:11 +0000 en-US hourly 1 Science method – Scientific Library 32 32 An innovative startup is developing a unique method to eliminate plastics from our oceans Sun, 14 Nov 2021 02:22:39 +0000

Our Cleaner Planet, a nonprofit startup with an innovative technique for removing plastics from our oceans, today announced that it has successfully completed prototype testing of its first plastic harvester and is now ready to go. moving forward with larger unit tests. The program is expected to launch the first of its full-size plastic harvesters into ocean operation in 2025.

(Photo: INDRANIL MUKHERJEE / AFP via Getty Images))

READ ALSO: Kenya installs power plant that turns seawater into drinking water

Pat Marshall, the founder of Our Cleaner Planet, says he and the development team are very encouraged by the test results of the prototype. “The test parameters of our 1: 164 scale prototype were set to assess speed and control as well as the first step in the filtration process,” he said. “We have surpassed all levels and are delighted to move to our scaled up test model.” Next up is a 1:12 scale unit that the team plans to start testing in early 2022.

Marshall, an accomplished aerospace engineer and senior executive with many years of aerospace research and development experience, created Our Cleaner Planet with a mission to harvest plastics from our oceans by developing innovative and sustainable methods that leverage proven engineering to create a cleaner, healthier environment. planet. Our Cleaner Planet has a patent pending design that not only focuses on larger macroplastics, but also much smaller micro and nano plastics. This is an important distinction because many current clean-up efforts focus only on the larger pieces of plastic, leaving the smaller pieces to continue to damage the ocean ecosystem and our global environment.

“The problem has grown to be much bigger than the sheer mass of plastic that is currently in our oceans. Plastic does not biodegrade. Instead, it breaks down into smaller pieces. These little pieces continue to get smaller and more toxic, creating a domino effect of damage extending from the fragile ecosystems of our oceans to our global environment and up the food chain to human ingestion, ”he said. revealed Marshall. “Removing plastics from the oceans is only part of the solution to this problem, but it is the first important step that Our Cleaner Planet will take.”

In its efforts to tackle this vast plastic problem, Our Cleaner Planet’s system will include a large ship that uses a process of harvesting plastic debris carried by the ocean. The process will not only remove macro and microplastics, but it will also introduce a unique method of removing nanoplastics down to 5 microns. The system will extend from surface level to a depth of 60 feet, allowing Our Cleaner Planet to more effectively remove plastics at much smaller and much deeper levels from the ocean. The company plans to develop a fleet of ships with each vessel capable of removing up to 1,000 tonnes of plastic from the oceans each year.

Marshall explained that Our Cleaner Planet is aiming for a net-zero harvesting system. “The plastics collected will then be transformed into fuel on board and each ship will be equipped with CO2 purifiers. Ash will be the only by-product of the process and the excess ash will be used more in other industries, finally completing the life cycle of the harvested plastic, ”he said.

Our Cleaner Planet was founded as a nonprofit in 2018, but Marshall has been working on the problem and its patent pending solution for over eight years. He brought together a team of professionals with decades of experience in piloting complex projects ranging from research and development to commercialization. Marshall says this gives them an added advantage in development and implementation.

“Instead of rushing to the ocean with an unproven design, wasting time and crucial investment capital, my team and I insisted on proving our concept and testing the design before releasing it to the public,” he said. he declared. Marshall and his team are currently seeking additional funding and support, and plan to launch Our Cleaner Planet’s first full-size ship in early 2025.

For more information on Our Cleaner Planet, the plastic pollution issue, or to find ways to support the program, please visit

RELATED ARTICLE: The World Without Oceans: What Does Our Fate Say?

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Bengaluru astronomers develop method to better study exoplanets Sat, 13 Nov 2021 06:47:08 +0000

Indian astronomers have developed a new method that could help better study the atmosphere of exoplanets using the polarization of light.

Their breakthrough is an algorithm that can increase the accuracy of exoplanet data by reducing contamination from Earth’s own atmosphere and disturbance from instrumental effects and other factors. This algorithm, called the Critical Noise Processing Algorithm, can help study the environment of exoplanets with better precision.

The algorithm was the result of the efforts of a team of researchers at the Indian Institute of Astrophysics (IIA) in Bengaluru who sought to understand the physical properties of exoplanets. The team’s goal was to explore Earth-like exoplanets and therefore try to identify which ones might be habitable.

Professor Sujan Sengupta of the Indian Institute of Astrophysics (IIA) in Bengaluru, had suggested decades ago that thermal radiation from exoplanets orbiting other stars would also be polarized. By measuring this polarization, he said scientists could also decipher the chemical composition and other atmospheric traits of these plants.

With this in mind, Professor Sengupta and his doctoral students Aritra Chakrabarty and Suman Saha have recently started using the ground-based optical telescopes available in India and data obtained from the Transiting Exoplanet Survey Satellite (TESS) space telescope. Almost immediately, they encountered challenges.

By cataloging the photometric data of several stars hosting planets, they discovered that the transit signals are strongly affected by noise from various sources that pose a challenge to accurately estimate the physical parameters of the planets.

This is where the team said it was forced to design a noise processing algorithm “that can process transit signals detected by terrestrial and space telescopes with much better accuracy than ever before.”

Saha and Sengupta demonstrated the effectiveness of this algorithm by critically analyzing data from the TESS space telescope, reducing instrumental noise and disturbances resulting from host star variability and pulsation, and accurately estimating physical parameters. of some exoplanets.

The work was published in The astronomical journal, a peer-reviewed scientific journal of the American Astronomical Society (AAS).

The IIA team collects data on exoplanets using the Himalayan Chandra Telescope at the Hanle Indian Astronomical Observatory and the Jagadish Chandra Bhattacharyya Telescope at the Vainu Bappu Observatory in Kavalur.

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New method proposed for an efficient structure Fri, 12 Nov 2021 19:18:18 +0000

image: The related result was posted on Langmuir as a cover story
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Credit: ZHANG Wei

Small particle number (CM) non-spherical clusters have potential applications in coatings, self-assembly of materials, biomedical diagnostics. The sphere has the smallest area under a certain volume, that is, the total Gibbs free energy of the surface is the lowest. Therefore, most nanoparticles have a spherical shape, which leads to difficult preparation of non-spherical CMs.

In an article published on Langmuir, a new method suggested by scientists at the Hefei Institutes of Physical Science (HFIPS), Chinese Academy of Sciences (CAS) solved this problem. In their recent research, the team proposed a synthetic pot pathway to prepare colloidal molecules (CMs) demonstrated in various morphologies such as popcorn, CO2, NH3, CH4.

“Our method, based on nucleation and growth of the surface of the seeds, aimed to prepare MCs of different morphologies in the same pot, so we called it the one-pot method”, explained Professor TIAN Xingyou, who led the team. “The mechanism allowed the synthesis of CM without any seed pretreatment or monomer swelling process, which holds great promise for production on an industrial scale.”

He further explained the process of forming the different CMs. The surface of the seeds, prepared with a soap-free emulsion, was coated with initiators which could be used for a subsequent styrene polymerization reaction to initiate the polymerization of the monomers. It formed the intermediate multi-core nanoparticles. As for the popcorn-like CMs, it is when the crosslinking agent divinylbenzene (DVB) and styrene (ST) were added simultaneously to the seed dispersion, the DVB would crosslink the PS chain to form a structure of 3D network and hamper the fusion of the PS cores. When the researchers simply added styrene or there is a one hour delay for adding the DVB crosslinking agent compared to adding styrene, AXn-type CMs could be obtained. This is mainly because DVB, which was not introduced or introduced later, could not prevent the process of fusing multiple nuclei of the PS at an early stage.

“This proved that the shape and size of CMs can be adjusted by changing the order of addition and content of ST and DVB,” TIAN Xingyou said, “This provided a good basis for self-assembly. . “

According to this research result, seed pretreatment and monomer swelling can be avoided. This dramatically shortens the manufacturing time. The discovery can take the manufacturing of CMs in a salable and reliable direction.

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of any press releases posted on EurekAlert! by contributing institutions or for the use of any information via the EurekAlert system.

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A new method for measuring quantum entanglement in a set of nuclear spins Fri, 12 Nov 2021 14:30:01 +0000

These are the three-dimensional spectral data the team obtained from the electronic proxy qubit, with spin wave modes corresponding to each “peak”. Horizontally, the qubit probes a fixed state of the nuclear assembly. Vertically, the state of the nuclear assembly is regulated by the qubit. Spectral asymmetry is a witness to quantum correlations between nuclei. It’s also somewhat symbolic as this work is the result of nearly two decades of continuous research efforts, by Cambridge researchers and many other teams, to achieve this demonstration of an entangled nuclear assembly. Credit: Gangloff et al.

One of the main goals of quantum physics studies is to measure the quantum states of large systems made up of many interacting particles. This could be particularly useful for the development of quantum computers and other quantum information processing devices.

Researchers at Cambridge University’s Cavendish Laboratory recently introduced a new approach to measure the spin states of a nuclear assembly, a system made up of many particles interacting with long-lived quantum properties. This method, presented in an article published in Physics of nature, works by exploiting the response of this system to collective spin excitations.

“For a dense set of quantum objects, like spins, it is not possible to measure each one individually, to learn how they interact with each other”, Claire Le Gall and Mete Atatüre, two of the researchers who have conducted the study, says “Instead, one can look for telltale signals in the collective response of the whole; much like the behavior of a flock of birds might say something about how birds engage with each other. others. Our system of interest is a large herd, or collection, of nuclear spins in a semiconductor quantum dot. “

In 2002, three Harvard University physicists discovered that large arrays of nuclear spins in a semiconductor quantum dot could be potential hosts for semiconductor quantum memories, and then published their work a year later. 19 years later, Le Gall, Atatüre and their colleagues probed this type of nuclear assembly using a quantum “proxy” bit, an electronic spin that couples simultaneously to all nuclear spins, as shown in their last article.

“We recently took an important step when we showed that the collective modes of the nuclear assembly (i.e. spin waves) can be coherently excited via the electron,” said Dorian Gangloff. , the first author of the article. “In our new study, we decided to use these electron-activated spin waves to change the state of the nuclear assembly and to read it. This would demonstrate a basic form of ‘writing’ and ‘reading’. via the spin of the electron. “

The idea behind the approach proposed by the scientists at Cambridge is that the type of nuclear spin wave mode that can be activated by electron spin depends on the state of the nuclear assembly that is being examined. For example, some spin wave modes increase the polarization of an ensemble (i.e. by how much all the spins point up) and others decrease it. The relative strength of these two different types of spin wave modes depends on how much an assembly is already “pointing up” or “pointing down”. up or down, ultimately allowing researchers to infer spin populations.

“But there is more: if the nuclear spins have interacted beforehand and accumulated some mutual information, which in this case may be quantum in nature, then the electron, as a quantum object with a one-to-one coupling. everything with those nuclei, feeling that pre-existing interaction, ”Atatüre said.“ It changes the strength of the spin wave modes that it can activate, and that’s what is very unique about our approach. As a result, by combining the measurements of several spin wave modes, we were able to use the electron as a “witness” for the entanglement among the nuclei in the set. “

The researchers’ method of observing multi-body systems using a “proxy” electronic spin qubit opens up new and interesting possibilities for probing nuclear assemblies without relying on individual spin readings. Unlike the previously proposed methods, their approach takes advantage of the native connectivity of a proxy qubit interacting with a dense nuclear assembly, ultimately extracting interesting information from these systems, including their quantum properties.

“Perhaps an analogy to our approach could be an orchestra, where we can tell if musicians perform well together without prior knowledge of each instrument separately,” said Le Gall. “Our study also showed for the first time that a set of nuclear spins in a semiconductor quantum dot (among the best single photon sources in the world) can harbor a multi-spin entanglement and therefore can be used as a large quantum resource efficiently connected to lightweight. “

In the future, the new technique for probing the spin states of nuclear assemblies could pave the way for the development of new quantum technologies. The research team are now trying to design the quantum dots examined in their paper to ensure that their sets of spins have greater coherence and exhibit more quantum properties.

“This will be essential if we are to use quantum dot nuclei for quantum memory,” Gangloff said. “Once we achieve more consistency, especially with a new generation of quantum dots, based on a different growth method, which shows a very promising hundredfold improvement over the quantum dots used so far – our plans are to shape nuclei into increasingly controlled quantum states, understand how entanglement is lost and can be preserved in this multibody system, and demonstrate that this resource can be used in quantum computing and computing. quantum communication. ”

Light used to detect quantum information stored in 100,000 nuclear quantum bits

More information:
Dorian A. Gangloff et al, Evidence of quantum correlations in a nuclear assembly via an electronic spin qubit, Physics of nature (2021). DOI: 10.1038 / s41567-021-01344-7

JM Taylor et al, Long-term memory for mesoscopic quantum bits, Physical examination letters (2003). DOI: 10.1103 / PhysRevLett.90.206803

DA Gangloff et al, Quantum interface of an electron and a nuclear assembly, Science (2019). DOI: 10.1126 / science.aaw2906

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IIT-M researchers develop new method to detect early signs of earthquakes Fri, 12 Nov 2021 13:33:42 +0000

A A team of researchers from the Indian Institute of Technology (IIT) -Madras has developed a new approach for the development of robust early warning systems for earthquakes through accurate detection and detection of the first series of seismic waves.

When an earthquake occurs, it produces a series of seismic waves. The first set of waves is called the P wave and it is harmless. Its early detection is vitally important as a good estimate of the time of its arrival would help develop a robust early warning system that could give a delay before the next set of destructive waves hit the ground. The delay can vary from 30 seconds to 2 minutes, mainly depending on the distance between the epicenter location and the monitoring site.

At first glance, the delays may seem minor. But they are significant. They are sufficient to shut down nuclear reactors, transportation like the subway, and to park elevators in high-rise buildings on the nearest floor, among many other measures that can save lives.

All existing P wave appearance detection methods are based on a combination of ideas from statistical signal processing and time series modeling.

However, these methods do not sufficiently take into account some advanced ideas. When combined with a so-called time-frequency or time-spectral localization method, the efficiency of such methods can be greatly improved.

The new IIT study fills this gap. It offers a new detector and automatic selector of real-time P waves in the prediction framework with a time-frequency localization function. The proposed approach provides a diverse set of capabilities to accurately detect the onset of the P wave, especially in so-called low signal-to-noise ratio (SNR) conditions that all existing methods fail. not to reach.


This research was undertaken by Kanchan Aggarwal, a doctoral student under the supervision of Professor Arun K Tangirala of the Department of Chemical Engineering, IIT Madras. A report on their study was published in the scientific journal PLOS ONE. The research was partially funded by the Board of Research in Nuclear Sciences, an advisory body of the Department of Atomic Energy.

Emphasizing the practical applications of their work, Professor Tangirala says: “The proposed framework is not necessarily limited to the detection of seismic events but is generic. It can also be used for fault detection and isolation in other areas. In addition, it can integrate any predictive model, including machine learning and deep learning models, which will reduce human intervention in detection.

Aggarwal says, “Information about the arrival of P waves is also crucial in determining other event source parameters, such as magnitude, depth and location of the epicenter. Therefore, a solution to the P-wave detection problem that is robust, precise and precise is essential to correctly estimate the details of the event and to reduce the damage caused by the earthquake or other triggered events.

(Courtesy of the article: India Science Wire)

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New research project will examine plants’ own method of releasing protein from seeds Fri, 12 Nov 2021 10:12:00 +0000

Researchers at the University of Copenhagen will study what plants do when they need to mobilize and use their seed proteins to germinate. If successful, they could potentially discover a more sustainable method of extracting food protein from plants using enzymes.

Photo: Lene Hundborg Koss

Protein from pea, bean and lentil seeds are good alternatives to meat, as they contain up to 40% protein. This is one of the reasons Poul Erik Jensen, professor in the Department of Food Sciences at the University of Copenhagen (UCPH FOOD), sees great potential in determining how best to use enzymes to extract seed proteins. Researchers are using pea seeds as a prototype.

“I see a lot of potential that we can use enzymes to extract proteins from the seeds of plants and develop them so that they can replace the less sustainable methods used today. At the same time, we hope to be able to increase the digestibility of vegetable proteins and thus create a method that can be implemented in sustainable and healthier food production, ”explains Poul Erik Jensen.

Today, proteins are often extracted from plants by “wet” processing, using water and chemicals.

“You first use a chemical solution in high pH water to extract the proteins, and then you collect them in a low pH solution, after which the material has to be dried. It is a heavy processing method because it requires water, time and a lot of energy, ”explains Poul Erik Jensen.

You can also choose a mechanical processing method, where you turn the dry peas into flour.

“But proteins are partially destroyed / modified by mechanical and wet processing methods, in the sense that they open up in different ways, which can affect functionality both negatively and positively. This has an impact on the sustainability of the processing as well as on the nutrition we get from the proteins, ”explains Poul Erik Jensen.

How does the plant mobilize and use its own proteins?

Photo of Professor Poul Erik Jensen
Professor at UCPH FOOD Poul Erik Jensen.

In the project, the researchers ask a key question:

“If the pea seed were to germinate, what would it do to mobilize the protein from the seed?” We would really like an answer to that, ”says Poul Erik Jensen.

The hypothesis is that plants, including pea seeds, are predisposed to extract the best possible nutrition from protein using their own natural method. This is basically what we want when we use protein for food – both for climatic and health reasons.

“If we know if there is a certain combination of enzymes that help soften the seed and release the protein, we can potentially use these enzymes for a gentler method of extraction than the methods used today,” explains Poul Erik Jensen.

Problem: We need to use less water

The idea is not new, as a similar method has been used in the bioethanol industry, where straw has been broken down and cellulose has been used as a substrate for cellulose degrading enzymes.

“This method is at the origin of all the thinking on bioethanol which has been very popular all over the world. Enzymes are used to cut the cellulose strands and turn them into sugar molecules, which are transformed into bioethanol with the help of yeast, which can then be used as fuel. And it is this reflection that we are going to try to apply to the proteins of the seeds ”, specifies Poul Erik Jensen.

But if we can use it in sustainable food production in the future, we need to use a lot less water in the process, he stresses.

“Traditionally, the process would require a lot of water, but we want to run the enzyme treatment with as little water as possible and make the seeds semi-liquid, like porridge. And if the enzymes are to work in the slurry, we have to move the material, so part of the project is to learn something about enzymatic flow processing, ”explains Poul Erik Jensen.

Therefore, we cannot live by eating untreated plants.

For many years there has been a rather negative perception of “processing” food. And that might be fair enough in some contexts. But Poul Erik Jensen points out that there are also a lot of transformations that result in plant nutrients being made available to us.

“For example, if we eat raw plants, some proteins will not be readily available to us because they are trapped in intact cells surrounded by a cell wall. Here, the proteins are not soluble, so we cannot derive the nutritional benefit that we could have had if they had been transformed ”, explains Poul Erik Jensen and continues:

“In the western world, where people typically eat more than enough calories and protein, it might work well, but it’s not good nutrition for kids or people who have to settle for less food. This is why we cannot base all of our food on plants that are not processed.

/ Public distribution. This material from the original organization / authors may be ad hoc in nature, edited for clarity, style and length. The views and opinions expressed are those of the author (s). See it in full here.

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New method has revealed the first “silent” black hole hidden beyond our galaxy Fri, 12 Nov 2021 02:02:11 +0000

The most stealthy monsters are often the most interesting.

And most stellar-mass black holes are silent monsters, floating invisibly through the great abyssal depths of space, showing no sign except the curvature of light via photons straying too close. This has forced astronomers to look for other ways to detect them, such as stars that appear to be locked in a strong binary orbit with what appears to be nothing at all.

And, for the first time, astronomers have successfully identified a black hole beyond our galaxy using this unconventional technique, according to a recent study published in the journal Monthly notices from the Royal Astronomical Society.

This could become a crucial step in revealing the evolution of black holes inside and outside our Milky Way.

How to spot a stellar mass stealth black hole

The suspicious movements of an orbiting star have revealed a black hole of comparable size in the Large Magellanic Cloud, which is a dwarf galaxy orbiting our own, about 160,000 light years away. Called NGC 1850, the black hole was found in a star cluster called NGC 1850 (celestial mapping is a logical practice), which contains thousands of stars. This recent detection suggests that the method could be crucial in finding black holes in densely populated star clusters, both within and beyond our enormous Milky Way. “Similar to Sherlock Holmes stalking a criminal gang from their missteps, we look at every star in this cluster with a magnifying glass in one hand trying to find evidence of the presence of black holes but not seeing them directly,” Sara said. Saracino, an astrophysicist at John Moores University in Liverpool, UK, in a report by Scientific alert.

“The result shown here is only one of the wanted criminals, but when you have found one you are on your way to finding many more, in different groups,” added Sarecino. The majority of the black holes listed so far beyond our Milky Way were easy to spot, as they launch inadmissible volumes of deadly radiation, meaning they actively suck up indescribable scales of matter, which are the real thing. source of radiation (since the black holes themselves reveal virtually nothing). Astronomers have identified more black holes via gravitational waves since the first were detected in 2015. This is when subtle ripples in the very fabric of spacetime are thrown in our direction as a result of a violent collision of two black holes. But despite all of our progress, these mapped black holes aren’t even the tip of the cosmic iceberg.

Baby black holes are waiting for us

There could be 100 million stellar mass black holes in our galaxy alone. Obviously, we have a lot more to do. And that also means that we have a lot to learn about those seemingly evil maws in the ancient depths of the darkest corners of the galaxy. But we don’t need to look them in the face to understand their properties, because the things they take with them, like gravitationally trapped stars, will reveal their secrets by the way they move.

Hundreds of thousands of light years away, these stars appear to be motionless. But the light of the stars themselves will change, its wavelength stretching and compressing as the solar oven moves closer and further away from us. And then we know they’re in the grip of a black hole. Continuing to study black holes in young star clusters could reveal more about how colossal stars and neutron stars are forged in the black holes we know and fear. And, since many of these star clusters are very young – NGC 1850 is only 100 million years old – it is possible to discover young black holes, which would provide a unique window into their complex and haunting evolution.

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The method, in mice, may eliminate the need for chemotherapy, radiation therapy, in the treatment of blood cancers, other diseases – sciencedaily Fri, 12 Nov 2021 00:16:15 +0000 For leukemias, lymphomas and other difficult-to-treat blood cancers, stem cell transplantation is the gold standard of care. The procedure involves replacing a patient’s own hematopoietic stem cells with a donor’s stem cells and in doing so, eradicating cancer cells in the blood, lymph nodes and bone marrow.

But many patients with such deadly blood cancers are too fragile to undergo stem cell transplants. This is because a patient’s stem cells must first be destroyed by intensive chemotherapy and sometimes full body irradiation before a donor’s stem cells are infused. This so-called conditioning regimen makes room for incoming donor stem cells, helps eliminate remaining cancer cells in the body, and depletes the patient’s immune system so that it cannot attack the donor stem cells. However, the toxicities and suppression of the immune system caused by conditioning regimens put patients at high risk for infections, organ damage and other potentially fatal side effects.

Now, studying mice, researchers at the Washington University School of Medicine in St. Louis have developed a method of stem cell transplantation that does not require radiation or chemotherapy. Instead, the strategy takes an immunotherapeutic approach, combining the targeted elimination of hematopoietic stem cells in the bone marrow with immunomodulatory drugs to prevent the immune system from rejecting new donor stem cells. With the new technique, mice have successfully undergone transplants of unrelated mouse stem cells without evidence of dangerously low blood cell counts characteristic of the traditional procedure. Data also suggests that such stem cell transplants may be effective against leukemia.

The study, available online in the Journal of Clinical Investigation, opens the door to a safer stem cell transplant, meaning more patients with various types of blood cancers could receive this potentially curative therapy, and it could be considered a treatment for other diseases, such as sickle cell anemia or other genetic disorders, which are less life threatening.

“Being able to do a stem cell transplant without having to administer radiation or chemotherapy would be a transformation,” said senior author and medical oncologist John F. DiPersio, MD, PhD, Virginia E. & Sam J. Golman and head of the oncology division of the Washington University School of Medicine. “This could eliminate dangerously low blood cell counts, bleeding complications, organ damage and infections. This has particular implications for performing bone marrow transplant or gene therapy for patients with disease. non-cancerous such as sickle cell anemia, where toxicities from chemotherapy- or It is important to avoid the conditioning associated with radiation. We still have some work to do before we are ready to translate these findings to people, but we are encouraged by the results of this study. “

As an alternative to high-dose chemotherapy and whole-body radiation therapy, DiPersio, who also heads the Center for Gene & Cellular Immunotherapy, and his colleagues have exploited drugs that are toxic to cells and paired these drugs with antibodies targeting specific surface proteins that are expressed primarily on stem cells in the bone marrow. It is only when these antibody-drug conjugates (ADCs) bind to these specific proteins that they are then internalized by the stem cells, resulting in the release of the payload of the drug inside the cell and , ultimately, cell death. Using ricin-derived saporin as the drug’s payload, the researchers generated two different ADCs to target two specific proteins found on the surface of blood stem cells, minimizing the risk of them damaging other types of cells. .

To prevent the recipient’s immune system from then rejecting the donor cells, the researchers treated the mice with immunosuppressive compounds called Janus kinase inhibitors (JAKs). In this study, the researchers mainly used baricitinib, which is approved by the Food and Drug Administration to treat rheumatoid arthritis. They found that baricitinib prevented the recipient’s immune cells, including T cells and natural killer cells, from attacking the donor’s stem cells.

“By combining the antibody-drug conjugates with JAK inhibitors, we have successfully transplanted between two completely independent mouse strains,” said lead author Stephen P. Persaud, MD, PhD, instructor in pathology and immunology. “A successful transplant across such a strict immunological barrier holds promise for potentially exploiting this technique for patients with leukemia.”

The researchers also found that the new technique balanced the donor’s immune cells attacking leukemia cells – called the graft-versus-leukemia effect – in a common mouse model of leukemia and not attacking the recipient’s healthy tissue, a dangerous condition called graft versus host disease. The mice in this study did not develop graft-versus-host disease because immunosuppressive drugs prevented it, another unique and significant benefit of this approach, according to the researchers.

“When you give JAK inhibitors early on, they are shown to prevent graft versus host disease from developing later,” said DiPersio, who is deputy director of the Siteman Cancer Center at Barnes-Jewish. Hospital and Washington University School of Medicine. . “Additionally, unlike a regular transplant using radiation therapy and chemotherapy as transplant conditioning, none of the mice developed a reduction in their blood count, which is the main life-threatening complication of traditional stem cell transplants. Chemotherapy and radiation therapy destroy all the old cells. With the new strategy, the old cells were slowly replaced by donor cells, so we never saw a drop in the number of blood cells in these mice. could see that all the blood cells were from the new donor cells. “

After a while, the researchers found that they could gradually reduce the JAK inhibitors and, once the donor stem cells completely replaced the original cells, completely stop the immune suppression.

“We have shown that we can use this relatively simple regimen which is low in toxicity to transplant donor stem cells across immunological barriers into mice,” said Persaud. “We need more research to see if the same strategy will be applicable to humans. We are working to optimize the technique in mice, and then we will probably test it in other animal models of leukemia before we start planning a clinical trial. to investigate the strategy in patients.

In collaboration with the Office of Technology Management at the University of Washington, DiPersio and Persaud filed a patent application for the combination of antibody-drug conjugates with JAK inhibitors for conditioning transplants.

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New method shows today’s warming is “unprecedented” in 24,000 years Wed, 10 Nov 2021 16:15:01 +0000

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November 10, 2021