Category Archives: nanotechnology

A smart shirt at the Canadian Space Agency

Caption: Canadian Space Agency astronaut David Saint-Jacques tries the Bio-Monitor, a new Canadian technology, for the first time in space (January 16, 2019). The innovative smart shirt system is designed to measure and record astronauts’ vital signs. Credit: Canadian Space Agency/NASA

Here’s a biosensor announcement from an April 27, 2021 Experimental Biology (annual meeting) news release on EurekAlert,

A technology-packed tank top offers a simple, effective way to track astronauts’ vital signs and physiological changes during spaceflight, according to research being presented at the American Physiological Society annual meeting during the Experimental Biology (EB) 2021 meeting, held virtually April 27-30.

By monitoring key health markers over long periods of time with one non-intrusive device, researchers say the garment can help improve understanding of how spaceflight affects the body.

“Until now, the heart rate and activity levels of astronauts were monitored by separate devices,” said Carmelo Mastrandrea, PhD, a postdoctoral fellow at the Schlegel-University of Waterloo Research Institute for Aging in Canada, and the study’s first author. “The Bio-Monitor shirt allows simultaneous and continuous direct measurements of heart rate, breathing rate, oxygen saturation in the blood, physical activity and skin temperature, and provides a continuous estimate of arterial systolic blood pressure.”

The Bio-Monitor shirt was developed for the Canadian Space Agency by Carré Technologies based on its commercially available Hexoskin garment. In a study funded by the Canadian Space Agency, a team of researchers from the Schlegel-University of Waterloo Research Institute for Aging oversaw the first test of the shirt in space for a scientific purpose. Astronauts wore the shirt continually for 72 hours before their spaceflight and 72 hours during spaceflight, except for periods of water immersion or when the device conflicted with another activity.

The shirt’s sensors and accelerometer performed well, providing consistent results and a large amount of usable data. Based on these initial results, researchers say the shirt represents an improvement over conventional methods for monitoring astronauts’ health, which require more hands-on attention.

“By monitoring continuously and non-intrusively, we remove the psychological impacts of defined testing periods from astronaut measurements,” said Mastrandrea. “Additionally, we are able to gather information during normal activities over several days, including during daily activities and sleep, something that traditional testing cannot achieve.”

In flight, the astronauts recorded far less physical activity than the two and a half hours per day recorded in the monitoring period before takeoff, a finding that aligns with previous studies showing large reductions in physical activity during spaceflight. In addition to monitoring astronauts’ health and physical activity in space, Mastrandrea noted that the shirt could provide early warning of any health problems that occur as their bodies re-adapt to gravity back on Earth.

The commercial version of the Bio-Monitor shirt is available to the public, where it can be used for various applications including assessing athletic performance and monitoring the health of people with limited mobility. In addition to spaceflight, researchers are examining its potential use in other occupational settings that involve extreme environments, such as firefighting.

Mastrandrea will present this research in poster R2888 (abstract). Contact the media team for more information or to obtain a free press pass to access the virtual meeting.

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About Experimental Biology 2021

Experimental Biology is an annual meeting comprised of thousands of scientists from five host societies and multiple guest societies. With a mission to share the newest scientific concepts and research findings shaping clinical advances, the meeting offers an unparalleled opportunity for exchange among scientists from across the U.S. and the world who represent dozens of scientific areas, from laboratory to translational to clinical research. http://www.experimentalbiology.org #expbio

About the American Physiological Society (APS)

Physiology is a broad area of scientific inquiry that focuses on how molecules, cells, tissues and organs function in health and disease. The American Physiological Society connects a global, multidisciplinary community of more than 10,000 biomedical scientists and educators as part of its mission to advance scientific discovery, understand life and improve health. The Society drives collaboration and spotlights scientific discoveries through its 16 scholarly journals and programming that support researchers and educators in their work. http://www.physiology.org

Mastrandrea’s abstract offers details explaining what makes this particular biosensor a new technology (from the ‘(R2888) Tracking astronaut physical activity and cardiorespiratory responses with the Bio-Monitor sensor shirt‘ abstract at the Experimental Biology (EB) 2021 meeting,

Carmelo Mastrandrea (Schlegel-UW Research Institute for Aging)| Danielle Greaves (Schlegel-UW Research Institute for Aging)| Richard Hughson (Schlegel-UW Research Institute for Aging)

Astronauts develop insulin resistance, and are at risk for cardiovascular deconditioning, during long-duration missions to the International Space Station (ISS) despite their daily exercise sessions (Hughson et al. Am J Physiol Heart Circ Physiol 310: H628–H638, 2016). Chronic unloading of the musculoskeletal and cardiovascular systems in microgravity dramatically reduces the challenge of daily activities, and the astronauts’ schedules limit them to approximately 30-min/day aerobic exercise. To understand the physical demands of spaceflight and how these change from daily life on Earth, the Vascular Aging experiment is equipping astronauts for 48-72h continuous recordings with the Canadian Space Agency’s Bio-Monitor wearable sensor shirt. The Bio-Monitor (Bio-M), developed from the commercial Hexoskin® device, consists of 3-lead ECG, thoracic and abdominal respiratory bands, 3-axis accelerometer, skin temperature and SpO2 sensor placed on the forehead. Our utilisation of this equipment necessitated the development of novel processing and visualisation techniques, to better interpret and guide subsequent data analyses [emphasis mine]. Here we present initial data from astronauts wearing the BioM prior to launch and aboard the ISS, demonstrating the ability to extract useful data from BioM, using software developed ‘in-house’.

Astronauts wore the Bio-M continually for 72-h except for periods of water immersion or when the device conflicted with another activity. After physical exercise, astronauts changed to a dry shirt. First, we assessed the key data-quality metrics to provide initial appraisals of acceptable recordings. Mean total recording length pre-flight (60.5 hours) was similar to that in-flight (66.5 hours), with a consistent distribution of recorded day (44% vs 45%, 6am-6pm) and night (56% vs 55%, 6pm-6am) hours (pre-flight vs in-flight respectively).

For each recording, quality assessment of ECG signals was performed for individual leads, before combining signals and cross-correlating R-waves to produce reliable heart-rate timings. Mean ECG quality for individual leads, represented here as the percentage of usable signal to total recording duration, was somewhat lower in-flight (92%) when compared to pre-flight (96%), likely caused by poor skin contact or dry shirt electrodes; combining lead signals as mentioned above improved the proportion of usable data to 97% and 98% respectively. Accelerometer recordings identified a significant reduction in high-force movements over the 72-hour recordings, with just over 2.5 hours/day of high-force activity in astronauts pre-flight vs 50 minutes/day in-flight. It should be noted however that accelerometer measurements in zero-gravity are likely to be reduced, and future refinement of activity data continues. Average heart rates in-flight showed little difference when compared to pre-flight, although future analyses will compare periods of sleep, rest, and activity to further refine this comparison.

We conclude that utilisation of the BioM hardware with our own analysis techniques produces high-quality data allowing for future interpretation and investigation of spaceflight-induced physiological adaptations.

As for Hexoskin (Carré Technologies inc.), I found out more on the About Us webpage of the Hexoskin website (Note: Links have been removed),

Hexoskin (Carré Technologies inc.)

Founded in 2006 in Montreal [Canada], Hexoskin is a growing private company, leader in non-invasive sensors, software, data science & AI services. The company headquartered in the bustling Rosemont neighborhood, provides solutions and services directly to customers & researchers; and through B2B contracts in pharmaceutical, academics, healthcare, security, defense, first responders, aerospace public & private organizations.

Hexoskin’s mission has always been to make the precise health data collected by its body-worn sensors accessible and useful for everyone. When the cofounders Pierre-Alexandre Fournier and Jean-François Roy started the company back in 2006, the existing technologies to report rich health data continuously didn’t exist. Hexoskin took a different approach to non-portable and invasive monitoring solutions by releasing in 2013 the first washable Smart Shirts that captures cardiac, respiratory, and activity body metrics. Today Hexoskin’s main R&D focus is the development of innovative body-worn sensors for health, mobile, and distributed software for health data management and analysis.

Since then, Hexoskin has designed the Hexoskin Connected Health Platform, a system to minimize user setup time and to maximize vital signs monitoring over long periods in a non-obstructive way with sensors embedded in a Smart Shirt. Data are synced to local and remote servers for health data management and analysis.
The Hexoskin Smart Garments are clinically validated and are developed involving patients & clients to be comfortable and easy to use.

The system is the next evolution to improve the standard of care in the following therapeutic areas: respiratory, cardiology, mental health, behavioral and physiological psychology, somnology, aging and physical performance, physical conditioning & wellbeing etc.

Next Generation Biometric Smart Shirts

Hexoskin supported the evolution of its 100% washable industry-leading Hexoskin Smart Garments to offer an easy and comfortable solution for continuously monitoring precise data during daily activities and sleep. Hexoskin is a machine washable Smart garment, designed and made in Canada that allows precise long-term monitoring of respiratory, cardiac and activity functions simultaneously, as well as sleep quality. 

Users are provided access the Hexoskin Connected Health Platform, an end-to-end system that supplies the tools to report and analyze precise data from the Hexoskin & third-party body-worn sensors. The platform offers apps for iOS, Android, and Watch OS devices. Users can access from anywhere an online dashboard with advanced reporting and analytics functionalities. Today, the Hexoskin Connected Platform is used worldwide and supported thousands of users and organizations to achieve their goals.

In 2019, Hexoskin launched the new Hexoskin ProShirt line for Men and Women with an all-new design to withstand the most active lifestyle and diverse daily living activities. The Hexoskin ProShirtcomes with built-in textile ECG & Respiratory sensors and a precise Activity sensor. The ProShirt works with the latest Hexoskin Smart recording device to offer uninterrupted continuous 24-hour monitoring. 

Today, the Hexoskin ProShirt are used by professional athletes for performance training, police & first responders for longitudinal stress monitoring, and patients in clinical trials living with chronic cardiac & respiratory conditions. 

Connected Health & Software Solutions

Hexoskin provides interoperable software solutions, secure and private infrastructure and data science services to support research and professional organizations. The system is designed to reduce the frequency of travel and allow remote communication between patients, study volunteers, caregivers, and researchers. Hexoskin is an efficient and precise solution that collects daily quantitative data from users, in their everyday lives, and over long periods of time. 

Conscious of the need for its users to understand how the data is collected and interpreted, Hexoskin early took a transparent approach by opening and documenting its Application Programing Interface (API). Today, part of Hexoskin’s success can be attributed to its community of developers and scientists that are leveraging its Connected Health Platform to create new applications and interventions not possible just a few years ago. 

Future Applications—remote health to space exploration

Since 2011, Hexoskin collaborated with the Canadian Space Agency on the Astroskin, a cutting edge Space Grade Smart Garment, now used in the International Space Station to monitor the astronauts’ health in Space. The Astroskin Vital Signs Monitoring Platform is also available to conduct research on earth.

Hexoskin hopes to bring the innovations developed for Space and its Hexoskin Connected Health Platform to support the growing need to provide patients’ access to affordable and adapted healthcare services remotely. Future applications include healthcare, chronic disease management, sleep medicine, aging at home, security & defense, and space exploration missions.

Hexoskin shirts, as noted earlier, are available commercially while inquiries about Astroskin shirts are welcomed (Note: Links have been removed),

Thinking that Astroskin will be perfect for your next study or project? Contact us  to discuss how Astroskin can support your next project. You can also request a demo of the Astroskin Vital Signs Monitoring Platform here.

Finally, I noticed that the researchers on this project were from the Schlegel-UW [University of Waterloo] Research Institute for Aging. I gather this was all about aging.

‘Nanotraps’ for catching and destroying coronavirus

‘Nanotraps’ are not vaccines although they do call the immune system into play. They represent a different way for dealing with COVID-19. (This work reminds of my June 24, 2020 posting Tiny sponges lure coronavirus away from lung cells where the researchers have a similar approach with what they call ‘nanosponges’.)

An April 27, 2021 news item on Nanowerk makes the announcement,

Researchers at the Pritzker School of Molecular Engineering (PME) at the University of Chicago have designed a completely novel potential treatment for COVID-19: nanoparticles that capture SARS-CoV-2 viruses within the body and then use the body’s own immune system to destroy it.

These “Nanotraps” attract the virus by mimicking the target cells the virus infects. When the virus binds to the Nanotraps, the traps then sequester the virus from other cells and target it for destruction by the immune system.

In theory, these Nanotraps could also be used on variants of the virus, leading to a potential new way to inhibit the virus going forward. Though the therapy remains in early stages of testing, the researchers envision it could be administered via a nasal spray as a treatment for COVID-19.

A scanning electron microscope image of a nanotrap (orange) binding a simulated SARS-CoV-2 virus (dots in green). Scientists at the University of Chicago created these nanoparticles as a potential treatment for COVID-19. Image courtesy Chen and Rosenberg et al.

An April 27, 2021 University of Chicago news release (also on EurekAlert) by Emily Ayshford, which originated the news item, describes the work in more detail,

“Since the pandemic began, our research team has been developing this new way to treat COVID-19,” said Asst. Prof. Jun Huang, whose lab led the research. “We have done rigorous testing to prove that these Nanotraps work, and we are excited about their potential.”

Designing the perfect trap

To design the Nanotrap, the research team – led by postdoctoral scholar Min Chen and graduate student Jill Rosenberg – looked into the mechanism SARS-CoV-2 uses to bind to cells: a spike-like protein on its surface that binds to a human cell’s ACE2 receptor protein.

To create a trap that would bind to the virus in the same way, they designed nanoparticles with a high density of ACE2 proteins on their surface. Similarly, they designed other nanoparticles with neutralizing antibodies on their surfaces. (These antibodies are created inside the body when someone is infected and are designed to latch onto the coronavirus in various ways).

Both ACE2 proteins and neutralizing antibodies have been used in treatments for COVID-19, but by attaching them to nanoparticles, the researchers created an even more robust system for trapping and eliminating the virus.

Made of FDA [US Food and Drug Administration]-approved polymers and phospholipids, the nanoparticles are about 500 nanometers in diameter – much smaller than a cell. That means the Nanotraps can reach more areas inside the body and more effectively trap the virus.

The researchers tested the safety of the system in a mouse model and found no toxicity. They then tested the Nanotraps against a pseudovirus – a less potent model of a virus that doesn’t replicate – in human lung cells in tissue culture plates and found that they completely blocked entry into the cells.

Once the pseudovirus bound itself to the nanoparticle – which in tests took about 10 minutes after injection – the nanoparticles used a molecule that calls the body’s macrophages to engulf and degrade the Nanotrap. Macrophages will generally eat nanoparticles within the body, but the Nanotrap molecule speeds up the process. The nanoparticles were cleared and degraded within 48 hours.

The researchers also tested the nanoparticles with a pseudovirus in an ex vivo lung perfusion system – a pair of donated lungs that is kept alive with a ventilator – and found that they completely blocked infection in the lungs.

They also collaborated with researchers at Argonne National Laboratory to test the Nanotraps with a live virus (rather than a pseudovirus) in an in vitro system. They found that their system inhibited the virus 10 times better than neutralizing antibodies or soluble ACE2 alone.

A potential future treatment for COVID-19 and beyond

Next the researchers hope to further test the system, including more tests with a live virus and on the many virus variants.

“That’s what is so powerful about this Nanotrap,” Rosenberg said. “It’s easily modulated. We can switch out different antibodies or proteins or target different immune cells, based on what we need with new variants.”

The Nanotraps can be stored in a standard freezer and could ultimately be given via an intranasal spray, which would place them directly in the respiratory system and make them most effective.

The researchers say it is also possible to serve as a vaccine by optimizing the Nanotrap formulation, creating an ultimate therapeutic system for the virus.

“This is the starting point,” Huang said. “We want to do something to help the world.”

The research involved collaborators across departments, including chemistry, biology, and medicine.

Here’s a link to and a citation for the paper,

Nanotraps for the containment and clearance of SARS-CoV-2 by Min Chen, Jillian Rosenberg, Xiaolei Cai, Andy Chao Hsuan Lee, Jiuyun Shi, Mindy Nguyen, Thirushan Wignakumar, Vikranth Mirle, Arianna Joy Edobor, John Fung, Jessica Scott Donington, Kumaran Shanmugarajah, Yiliang Lin, Eugene Chang, Glenn Randall, Pablo Penaloza-MacMaster, Bozhi Tian, Maria Lucia Madariaga, Jun Huang. Matter, April 19, 2021, DOI: https://doi.org/10.1016/j.matt.2021.04.005

This paper appears to be open access.

Nanotechnology in agriculture: an introduction and a 15th anniversary

It’s not often that I publish a posting meant for beginners since I tend to take an understanding of nanotechnology for granted. For anyone who has stumbled across this posting and needs an introduction to nanotechnology, M Cynthia Goh’s* (professor, Chemistry, University of Toronto) April 25, 2021 essay about nanotechnology and agriculture, on The Conversation website, provides a good entry point (Note 1: The excerpts are not in the order in which they appear in the essay Note 2: Links have been removed) ,

Nanotechnology is the science of objects that are a few nanometres — billionths of a metre — across. At this size, objects acquire unique properties. For example, the surface area of a swarm of nanoscale particles is enormous compared to the same mass collected into single large-scale clump.

Varying the size and other properties of nanoscale objects gives us an unprecedented ability to create precision surfaces with highly customized properties.

Agriculture is one of the oldest human inventions, but nanotech provides modern innovations that could dramatically improve the efficiency of our food supply and reduce the environmental impact of its production.

Agriculture comes with costs that farmers are only too familiar with: Crops require substantial amounts of water, land and fuel to produce. Fertilizers and pesticides are needed to achieve the necessary high crop yields, but their use comes with environmental side effects, even as many farmers explore how new technologies can reduce their impact.

Custom-made nanoscale systems can use precision chemistry to achieve high-efficiency delivery of fertilizers or pesticides. These active ingredients can be encapsulated in a fashion similar to what happens in targeted drug delivery. The encapsulation technique can also be used to increase the amount dissolved in water, reducing the need for large amounts.

Current applications

Starpharma, a pharmaceutical company, got into this game a few years ago, when it set up a division to apply its nanotechnological innovations to the agriculture sector. The company has since sold its agrochemical business.

Psigryph is another innovative nanotech company in agriculture. Its technology uses biodegradable nanostructures derived from Montmonercy sour cherries extract to deliver bioactive molecules across cell membranes in plants, animals and humans.

My lab has spent years working in nanoscience, and I am proud to see our fundamental understanding of manipulating polymer encapsulation at the nanoscale make its way to applications in agriculture. A former student, Darren Anderson, is the CEO of Vive Crop Protection [emphasis mine], named one of Canada’s top growing firms: they take chemical and biological pesticides and suspend them in “nanopackets” — which act as incredibly small polymer shuttles — to make them easily reach their target. The ingredients can be controlled and precisely directed when applied on crops.

*M Cynthia Goh was a co-founder of Vive Crop Protection but is not actively involved in the company. She receives funding from NSERC (Natural Sciences and Engineering Research Council) Canada and the Ontario Centre of Innovation.

Vive Crop Protection’s 15th anniversary

March 30, 2021 marked 15 years for Vive Crop Protection (formerly Vive Nano) according to the company’s March 30, 2021 news release. It’s been a number of years since I’ve written about the company and I’m glad to see they seem to be thriving. Chief Executive Officer (CEO), Darren Anderson (he was formerly the company’s Chief Technical Officer) was interviewed on camera by Kim Bolton for BNN Bloomberg; a link to the video is available from this April 29, 2021 Vive Crop news webpage.

(BTW, BNN Bloomberg is “(formerly Business News Network and Report on Business Television) is a Canadian English language specialty channel owned by Bell Media. It broadcasts programming related to business and financial news and analysis. Since April 30, 2018, the network has operated as a partner of the U.S. business channel Bloomberg Television, …” See more about BNN Bloomberg in its Wikipedia entry.)

For anyone interested in Vive Crop’s technology, see my December 31, 2013, posting.

Follow up to the Charles M. Lieber affair and US government efforts to prosecute nanotech scientists

Rebecca Trager in a March 5, 2021 news article for Chemistry World highlights support for Charles M. Lieber (Harvard professor and chair of the chemistry department) from his colleagues (Note: Links have been removed),

More than a year after the chair of Harvard University’s chemistry department was arrested for allegedly hiding his receipt of millions of dollars in research funding from China from his university and the US government, dozens of prominent researchers – including many Nobel Prize winners – are coming to Charles Lieber’s defence. They are calling the US Department of Justice (DOJ) case against him ‘unjust’ and urging the agency to drop it.

Following his January 2020 arrest, Lieber was placed on ‘indefinite’ paid administrative leave. The nanoscience pioneer was indicted in June [2020] on charges of making false statements to federal authorities regarding his participation in China’s Thousand Talents plan – the country’s programme to attract, recruit and cultivate high-level scientific talent from abroad. Lieber faces up to five years in prison and a fine of $250,000 (£179,000) if convicted.

A 1 March [2021] open letter, drafted and coordinated by Harvard chemist Stuart Schreiber, co-founder of the Broad Institute, and professor emeritus Elias Corey, winner of the 1990 chemistry Nobel prize, says Lieber became the target of a ‘tragically misguided government campaign’. The letter refers to Lieber as ‘one of the great scientist of his generation’ and warns such government actions are discouraging US scientists from collaborating with peers in other countries, particularly China. The open letter also notes that Lieber is fighting to salvage his reputation while suffering from incurable lymphoma.

Ferguson goes on to contrast Lieber’s treatment by Harvard to another embattled colleague’s treatment by his home institution (Note: Links have been removed),

Harvard’s treatment of Lieber stands in contrast to how the Massachusetts Institute of Technology (MIT) handled the more recent case of nanotechnologist Gang Chen, who was arrested in January [2021] for failing to report his ties to the Chinese government. MIT agreed to cover his legal fees, and more than 100 faculty members signed a letter to their university’s president that picked apart the DOJ’s allegations against Chen.

I have more details about the case against Lieber (as it was presented at the time) in a January 28, 2020 posting.

As for Professor Chen, I found this MIT statement dated January 14, 2021 (the date of his arrest) and this January 14, 2021 statement from The United States District Attorney’s Office District of Massachusetts.

Protocols for mouse-human chimeric embryos

This work on a type of species boundary-crossing could be very disturbing for some folks. That said, here’s more about the science from a July 2, 2021 news item on phys.org,

A year after University at Buffalo [in New York state] scientists demonstrated that it was possible to produce millions of mature human cells in a mouse embryo, they have published a detailed description of the method so that other laboratories can do it, too.

A July 2, 2021 University at Buffalo (UB) news release (also on EurekAlert) by Ellen Goldbaum, which originated the news item, explains why scientists have created these chimeras,

The ability to produce millions of mature human cells in a living organism, called a chimera, which contains the cells of two species, is critical if the ultimate promise of stem cells to treat or cure human disease is to be realized. But to produce those mature cells, human primed stem cells must be converted back into an earlier, less developed naive state so that the human stem cells can co-develop with the inner cell mass in a mouse blastocyst.

The protocol outlining how to do that has now been published in Nature Protocols by the UB scientists. They were invited to publish it because of the significant interest generated by the team’s initial publication describing their breakthrough last May [2020].

“This paper will enable many scientists to use this new platform to study the human disease of their interest,” said Jian Feng, PhD, professor of physiology and biophysics in the Jacobs School of Medicine and Biomedical Sciences at UB and senior author. “Over time, it will transform biomedical research toward a more effective use of the human model system to directly study virtually any inborn condition of an individual. It will stimulate unforeseen discoveries and applications that may fundamentally change our understanding of human biology and medicine.”

The protocol will allow scientists to create animal models that Feng said provide a much more realistic picture of embryonic development than has ever been possible. These more realistic animal models also will have the potential to reveal the mechaniswms behind numerous diseases, especially those that afflict individuals from birth.

Better mouse models

“This step-by-step protocol will benefit the entire field by enabling other scientists to use our methods to generate chimeras to study human diseases that they are experts in,” said Feng. “It will lead to the generation of better mouse models for various human diseases, such as sickle cell anemia, COVID-19 and many others, or various human developmental disorders.” The paper demonstrates how to generate naive human pluripotent stem cells from existing induced pluripotent stem cells that may be derived from patients with various diseases, how to generate mouse-human chimeras using these cells and how to quantify the amount of human cells in the chimeras.

“Using our method, one can now track the development of naive human pluripotent stem cells in mouse-human chimeric embryos in real-time,” said Feng. These stem cells can then be manipulated either genetically or pharmacologically, providing valuable information about human development and disease.

“For example, one can label naive human pluripotent stem cells by inserting green fluorescent protein in a hemoglobin gene to study the development of human red blood cells in mouse-human chimeras,” said Feng.

Another application is to generate humanized mouse models to study many human diseases.

“These mice contain critical human cells, tissues or even organs so that they more accurately reflect the human condition,” said Feng. “With our method, the human cells are made along with the mouse during the development of the mouse embryo. There would be better matching and no rejections, because there are ways for the human cells to be made where there is no competition from their mouse counterparts.”

Organs for transplant in the future

By allowing others to improve and adapt the method to eventually generate chimeras in larger animals, this protocol may also lead to the generation of human organs to address the dire shortage of organs available for transplant, said Feng.

“If naive human pluripotent stem cells are able to generate significant amounts of mature human cells in other larger species, it could be possible to make human tissues or even human organs in chimeric animals,” Feng explained.

This would be possible using blastocyst complementation where, Feng explained, normal pluripotent stem cells from one species can reconstitute an organ for that species in a blastocyst of another species that been genetically modified not to grow that particular organ.

Feng added: “Ultimately, a better understanding of how human cells develop and grow in chimeras may enable the generation of human cells, tissues and organs in a completely artificial system and fundamentally change how we treat many human diseases. Research using chimeras is a bridge that must be crossed to reach that possibility.”

Here’s a link to and a citation for the 2021 article,

Generation of mouse–human chimeric embryos by Boyang Zhang, Hanqin Li, Zhixing Hu, Houbo Jiang, Aimee B. Stablewski, Brandon J. Marzullo, Donald A. Yergeau & Jian Feng. Nature Protocols (2021) DOI: https://doi.org/10.1038/s41596-021-00565-7 Published 02 July 2021

This article is behind a paywall.

Here’s a link to and citation for the 2020 work, which led to the publication of the protocols,

Transient inhibition of mTOR in human pluripotent stem cells enables robust formation of mouse-human chimeric embryos by Zhixing Hu, Hanqin Li, Houbo Jiang, Yong Ren, Xinyang Yu, Jingxin Qiu, Aimee B. Stablewski, Boyang Zhang, Michael J. Buck, Jian Feng. Science Advances 13 May 2020: Vol. 6, no. 20, eaaz0298 DOI: 10.1126/sciadv.aaz0298

This paper is open access.

Five country survey of reactions to food genome editing

Weirdly and even though most of this paper’s authors are from the University of British Columbia (UBC; Canada), only one press release was issued and that was by the lead author’s (Gesa Busch) home institution, the University of Göttingen (Germany).

I’m glad Busch, the other authors, and the work are getting some attention (if not as much as I think they should).

From a July 9, 2021 University of Göttingen press release (also on EurekAlert but published on July 12, 2021),

A research team from the University of Göttingen and the University of British Columbia (Canada) has investigated how people in five different countries react to various usages of genome editing in agriculture. The researchers looked at which uses are accepted and how the risks and benefits of the new breeding technologies are rated by people. The results show only minor differences between the countries studied – Germany, Italy, Canada, Austria and the USA. In all countries, making changes to the genome is more likely to be deemed acceptable when used in crops rather than in livestock. The study was published in Agriculture and Human Values.

Relatively new breeding technologies, such as CRISPR [clustered regularly interspaced short palindromic repeats) gene editing, have enabled a range of new opportunities for plant and animal breeding. In the EU, the technology falls under genetic engineering legislation and is therefore subject to rigorous restrictions. However, the use of gene technologies remains controversial. Between June and November 2019, the research team collected views on this topic via online surveys from around 3,700 people from five countries. Five different applications of gene editing were evaluated: three relate to disease resistance in people, plants, or animals; and two relate to achieving either better quality of produce or a larger quantity of product from cattle.

“We were able to observe that the purpose of the gene modification plays a major role in how it is rated,” says first author Dr Gesa Busch from the University of Göttingen. “If the technology is used to make animals resistant to disease, approval is greater than if the technology is used to increase the output from animals.” Overall, however, the respondents reacted very differently to the uses of the new breeding methods. Four different groups can be identified: strong supporters, supporters, neutrals, and opponents of the technology. The opponents (24 per cent) identify high risks and calls for a ban of the technology, regardless of possible benefits. The strong supporters (21 per cent) see few risks and many advantages. The supporters (26 per cent) see many advantages but also risks. Whereas those who were neutral (29 per cent) show no strong opinion on the subject.

This study was made possible through funding from the Free University of Bozen-Bolzano and Genome BC.

Here’s a link to and a citation for the paper,

Citizen views on genome editing: effects of species and purpose by Gesa Busch, Erin Ryan, Marina A. G. von Keyserlingk & Daniel M. Weary. Agriculture and Human Values (2021) Published: DOI: https://doi.org/10.1007/s10460-021-10235-9

This paper is open access.

Methodology

I have one quick comment about the methodology. It can be difficult to get a sample that breaks down along demographic lines that is close to or identical to national statistics. That said, it was striking to me that every country was under represented in the ’60 years+ ‘ category. In Canada, it was by 10 percentage points (roughly). For other countries the point spread was significantly wider. In Italy, it was a 30 percentage point spread (roughly).

I found the data in the Supplementary Materials yesterday (July 13, 2021). When I looked this morning, that information was no longer there but you will find what appears to be the questionnaire. I wonder if this removal is temporary or permanent and, if permanent, I wonder why it was removed.

Participants for the Canadian portion of the survey were supplied by Dynata, a US-based market research company. Here’s the company’s Wikipedia entry and its website.

Information about how participants were recruited was also missing this morning (July 14, 2021).

Genome British Columbia (Genome BC)

I was a little surprised when I couldn’t find any information about the program or the project on the Genome BC website as the organization is listed as a funder.

There is a ‘Genomics and Society’ tab (seems promising, eh?) on the homepage where you can find the answer to this question: What is GE³LS Research?,

GE3LS research is interdisciplinary, conducted by researchers across many disciplines within social science and humanities, including economics, environment, law, business, communications, and public policy.

There’s also a GE3LS Research in BC page titled Project Search; I had no luck there either.

It all seems a bit mysterious to me and, just in case anything else disappears off the web, here’s a July 13, 2021 news item about the research on phys.org as backup to what I have here.

A lobster’s stretch and strength in a hydrogel

An MIT team has fabricated a hydrogel-based material that mimics the structure of the lobster’s underbelly, the toughest known hydrogel found in nature. Credits: Courtesy of the researchers

I love this lobster. In most photos, they’re food. This shows off the lobster as a living entity while showcasing its underbelly, which is what this story is all about. From an April 23, 2021 news item on phys.org (Note: A link has been removed),

A lobster’s underbelly is lined with a thin, translucent membrane that is both stretchy and surprisingly tough. This marine under-armor, as MIT [Massachusetts Institute of Technology] engineers reported in 2019, is made from the toughest known hydrogel in nature, which also happens to be highly flexible. This combination of strength and stretch helps shield a lobster as it scrabbles across the seafloor, while also allowing it to flex back and forth to swim.

Now a separate MIT team has fabricated a hydrogel-based material that mimics the structure of the lobster’s underbelly. The researchers ran the material through a battery of stretch and impact tests, and showed that, similar to the lobster underbelly, the synthetic material is remarkably “fatigue-resistant,” able to withstand repeated stretches and strains without tearing.

If the fabrication process could be significantly scaled up, materials made from nanofibrous hydrogels could be used to make stretchy and strong replacement tissues such as artificial tendons and ligaments.

The team’s results are published in the journal Matter. The paper’s MIT co-authors include postdocs Jiahua Ni and Shaoting Lin; graduate students Xinyue Liu and Yuchen Sun; professor of aeronautics and astronautics Raul Radovitzky; professor of chemistry Keith Nelson; mechanical engineering professor Xuanhe Zhao; and former research scientist David Veysset Ph.D. ’16, now at Stanford University; along with Zhao Qin, assistant professor at Syracuse University, and Alex Hsieh of the Army Research Laboratory.

An April 23, 2021 MIT news release (also on EurekAlert) by Jennifer Chu, which originated the news item, offers an overview of the groundwork for this latest research along with technical detail about the latest work,

Nature’s twist

In 2019, Lin and other members of Zhao’s group developed a new kind of fatigue-resistant material made from hydrogel — a gelatin-like class of materials made primarily of water and cross-linked polymers. They fabricated the material from ultrathin fibers of hydrogel, which aligned like many strands of gathered straw when the material was repeatedly stretched. This workout also happened to increase the hydrogel’s fatigue resistance.

“At that moment, we had a feeling nanofibers in hydrogels were important, and hoped to manipulate the fibril structures so that we could optimize fatigue resistance,” says Lin.

In their new study, the researchers combined a number of techniques to create stronger hydrogel nanofibers. The process starts with electrospinning, a fiber production technique that uses electric charges to draw ultrathin threads out of polymer solutions. The team used high-voltage charges to spin nanofibers from a polymer solution, to form a flat film of nanofibers, each measuring about 800 nanometers — a fraction of the diameter of a human hair.

They placed the film in a high-humidity chamber to weld the individual fibers into a sturdy, interconnected network, and then set the film in an incubator to crystallize the individual nanofibers at high temperatures, further strengthening the material.

They tested the film’s fatigue-resistance by placing it in a machine that stretched it repeatedly over tens of thousands of cycles. They also made notches in some films and observed how the cracks propagated as the films were stretched repeatedly. From these tests, they calculated that the nanofibrous films were 50 times more fatigue-resistant than the conventional nanofibrous hydrogels.

Around this time, they read with interest a study by Ming Guo, associate professor of mechanical engineering at MIT, who characterized the mechanical properties of a lobster’s underbelly. This protective membrane is made from thin sheets of chitin, a natural, fibrous material that is similar in makeup to the group’s hydrogel nanofibers.

Guo found that a cross-section of the lobster membrane revealed sheets of chitin stacked at 36-degree angles, similar to twisted plywood, or a spiral staircase. This rotating, layered configuration, known as a bouligand structure, enhanced the membrane’s properties of stretch and strength.

“We learned that this bouligand structure in the lobster underbelly has high mechanical performance, which motivated us to see if we could reproduce such structures in synthetic materials,” Lin says.

Angled architecture

Ni, Lin, and members of Zhao’s group teamed up with Nelson’s lab and Radovitzky’s group in MIT’s Institute for Soldier Nanotechnologies, and Qin’s lab at Syracuse University, to see if they could reproduce the lobster’s bouligand membrane structure using their synthetic, fatigue-resistant films.

“We prepared aligned nanofibers by electrospinning to mimic the chinic fibers existed in the lobster underbelly,” Ni says.

After electrospinning nanofibrous films, the researchers stacked each of five films in successive, 36-degree angles to form a single bouligand structure, which they then welded and crystallized to fortify the material. The final product measured 9 square centimeters and about 30 to 40 microns thick — about the size of a small piece of Scotch tape.

Stretch tests showed that the lobster-inspired material performed similarly to its natural counterpart, able to stretch repeatedly while resisting tears and cracks — a fatigue-resistance Lin attributes to the structure’s angled architecture.

“Intuitively, once a crack in the material propagates through one layer, it’s impeded by adjacent layers, where fibers are aligned at different angles,” Lin explains.

The team also subjected the material to microballistic impact tests with an experiment designed by Nelson’s group. They imaged the material as they shot it with microparticles at high velocity, and measured the particles’ speed before and after tearing through the material. The difference in velocity gave them a direct measurement of the material’s impact resistance, or the amount of energy it can absorb, which turned out to be a surprisingly tough 40 kilojoules per kilogram. This number is measured in the hydrated state.

“That means that a 5-millimeter steel ball launched at 200 meters per second would be arrested by 13 millimeters of the material,” Veysset says. “It is not as resistant as Kevlar, which would require 1 millimeter, but the material beats Kevlar in many other categories.”

It’s no surprise that the new material isn’t as tough as commercial antiballistic materials. It is, however, significantly sturdier than most other nanofibrous hydrogels such as gelatin and synthetic polymers like PVA. The material is also much stretchier than Kevlar. This combination of stretch and strength suggests that, if their fabrication can be sped up, and more films stacked in bouligand structures, nanofibrous hydrogels may serve as flexible and tough artificial tissues.

“For a hydrogel material to be a load-bearing artificial tissue, both strength and deformability are required,” Lin says. “Our material design could achieve these two properties.”

If you have the time and the interest, do check out the April 23, 2021 MIT news release, which features a couple of informative GIFs.

Here’s a link to and a citation for the paper,

Strong fatigue-resistant nanofibrous hydrogels inspired by lobster underbelly by Jiahua Ni, Shaoting Lin, Zhao Qin, David Veysset, Xinyue Liu, Yuchen Sun, Alex J. Hsieh, Raul Radovitzky, Keith A. Nelson, Xuanhe Zhao. Matter, 2021; DOI: 10.1016/j.matt.2021.03.023 Published April 23, 2021

This paper is behind a paywall.

Nanomaterials are now nanoforms?

There’s a proposal/recommendation/call to start calling nanomaterials ‘nanoforms’ according to an April 20, 2021 article (you can also find it here on JDSupra) by Lynn Bergeson and Carla N. Hutton in April 27, 2021 (Volume XI, Number 117) issue of the National Law Review,

The Nanotechnology Industries Association (NIA) has published a March 2021 position paper, A changing regulatory landscape and language for the nanoscale, that examines the transition from “nanomaterial” to “nanoforms” to reflect better the differences in nanomaterial properties both in relation to bulk counterparts and to nanoforms of the same substance.  In the paper, NIA describes a transition phase where the language of nanoforms is used more widely and examples of nanoform sets can be increasingly demonstrated in the public domain, while there is still a “significant” learning curve for both industry and the European Chemicals Agency (ECHA).  NIA recommends that all stakeholders reassess the language they use where relevant, “particularly when discussing hazard, and where non-specific terminology may be misleading and result in confusion and mistrust in the safety of substances at the nanoscale.” …

I haven’t noticed the use of nanoforms yet but, going forward, I will be alert to the change in terminology.