Stem Cell Sheets Harvested in Just Two Days (Medicine)

POSTECH and Pohang Semyung Christianity Hospital joint research team develops a thermoresponsive nanotopography cell culture platform.

Stem cells are cell factories that constantly divide themselves to create new cells. Implanting stem cells in damaged organs can regenerate new tissues. Cell sheet engineering, which allows stem cells to be transplanted into damaged areas in the form of sheets made up of only cells, completely eliminates immune rejection caused by external substances and encourages tissue regeneration. A research team led by POSTECH recently succeeded in drastically reducing the harvest period of such stem cell sheets.

A joint research team comprised of Professor Dong Sung Kim and researcher Andrew Choi of POSTECH’s Department of Mechanical Engineering and Dr. InHyeok Rhyou and Dr. Ji-Ho Lee of the Department of Orthopedic Surgery at Pohang Semyung Christianity Hospital has significantly reduced the total harvest period of a stem cell sheet to two days. The nanotopography of poly(N-isopropylacrylamide) (PNIPAAm), which abruptly changes its roughness depending on temperature, allows harvesting of cell sheets that consist of mesenchymal stem cells derived from human bone marrow. Considering that it takes one week on average to make stem cells into sheets using the existing techniques developed so far, this is the shortest harvest time on record. These research findings were published as a cover paper in the latest issue of Biomaterials Science, an international journal in the biomaterials field.

Professor Kim’s research team focused on PNIPAAm, a polymer that either combines with water or averts it depending on the temperature. In previous studies, PNIPAAm has been introduced as a coating material for cell culture platform to harvest cell sheets, but the range of utilization had been hampered due to the limited types of cells that can be made into sheets. For the first time in 2019, the research team developed a technology of easily regulating the roughness of 3D bulk PNIPAAm and has stably produced various types of cells into sheets.

The study conducted this time focused on making stem cells – that are effective in tissue regeneration – into sheets in a short time in order to increase their direct utility. The team achieved this by applying an isotropic pattern of nanopores measuring 400 nanometers (nm, 1 billionth of a meter) on the surface of a 3D bulk PNIPAAm. As a result, not only did the formation and maturity of human bone marrow-derived mesenchymal stem cells on the nanotopography of bulk PNIPAAm accelerate, but the surface roughness of bulk PNIPAAm at room temperature below the lower critical solution temperature (LCST)*1 was also rapidly increased, effectively inducing the detachment of cell sheets. This in turn enabled the rapid harvesting of human bone marrow-derived mesenchymal stem cell sheets.

“At least five days are needed to harvest stem cell sheets reported through previous researches,” commented Andrew Choi, the “ author of the paper. “We can now harvest them in just two days with the PNIPAAm nanotopography developed this time.”

“We have significantly shortened the harvest time by introducing nanotopography on the surface of the 3D bulk PNIPAAm to produce mature stem cell sheets for the first time in the world,” remarked Professor Dong Sung Kim who led the study. He added, “We have opened up the possibility of applying the sheets directly to patients in the future.”

The research was conducted with the support from Basic Research Program (Mid-career Researcher Program) and the Biomedical Technology Development Program of the National Research Foundation and the Ministry of Science and ICT of Korea.

Provided by POSTECH

Terahertz Zaps Alter Gene Activity In Stem Cells (Biology)

A new apparatus improves how we study the effects of aiming high-field terahertz radiation at cells, with implications for regenerative medicine.

Terahertz light pulses change gene expression in stem cells, report researchers from Kyoto University’s Institute for Integrated Cell-Material Sciences (iCeMS) and Tokai University in Japan in the journal Optics Letters. The findings come thanks to a new tool, with implications for stem cell research and regenerative therapy development.

Using the apparatus, which effectively exposes iPSCs to terahertz radiation, the researchers found that terahertz light pulses change the activity of genes influenced by zinc-dependent transcription factors (Mindy Takamiya/Kyoto University iCeMS (CC BY-NC-SA 4.0))

Terahertz waves fall in the far infrared/microwave part of the electromagnetic spectrum and can be produced by powerful lasers. Scientists have used terahertz pulses to control the properties of solid-state materials. They also have potential for manipulating living cells, as they don’t damage them the way that ultraviolet or infrared light does. Research so far has led to contradictory findings about their effects on cells, possibly because of the way the experiments have been conducted.

iCeMS microengineer Ken-ichiro Kamei and physicist Hideki Hirori worked with colleagues to develop a better tool for investigating what happens when terahertz pulses are shone on human cells. The apparatus overcomes issues with previous techniques by placing cells in tiny microwells that have the same area as the terahertz light.

The team used the apparatus to explore the effects of terahertz radiation on induced pluripotent stem cells (iPSCs). These are cells that have been taken from skin or blood and changed into stem cells. Scientists are seeking to turn them into other types of cells and tissues to help treat diseases like muscular dystrophy.

“Terahertz pulses can generate a strong electric field without touching or damaging cells,” says Hirori. “We tested their effect on iPSCs and discovered that the activity of some gene networks changes as a result of terahertz light exposure.”

For example, they found the pulses activated genes involved in motor neuron survival and mitochondrial function. They also deactivated genes involved in cell differentiation, the process in which stem cells change into specialized body cells.

Further investigation found that these genes were influenced by zinc-dependent transcription factors. The scientists believe the terahertz pulses generate an electric field that causes zinc ions to move inside cells, impacting the function of transcription factors, which in turn activate or deactivate the genes they are responsible for.

Hirori says the findings could aid efforts to develop a technology that can manipulate iPSC differentiation into specific cells by turning off specific genes while keeping others on, paving the way for regenerative therapies for a wide range of diseases.

References: Takehiro Tachizaki, Reiko Sakaguchi, Shiho Terada, Ken-ichiro Kamei, and Hideki Hirori (2020). Terahertz pulse-altered gene networks in human induced pluripotent stem cells. Optics Letters. Doi: https://doi.org/10.1364/OL.402815

Provided by Kyoto University

Who Am I? (Psychology)

Role models and biological factors shape who we are. But our selves change throughout our lives. Over time, it is not only our appearance, our relationships and our circumstances that change, our identity changes too – and yet we feel we are still the same.

Who am I? It’s one of life’s Big Questions. And we might come up with very different answers – depending on when, why and where we ask it. Because our selves are not set in stone; in fact, they are extremely malleable. Over time, it is not only our appearance, our relationships and our circumstances that change, but also how we see ourselves and how we define our identity. Our self-concept – the part of our identity that we can put into words – is completely different at 20, 40, 60 or 80.

This calls to mind the Ship of Theseus paradox, which philosophers were already puzzling over in ancient times. The legendary King Theseus from Greek mythology removed the old planks from his ship and replaced them one by one with new ones over many years, right down to the very last plank. Is the entirely restored boat still Theseus’ ship, or has it become something entirely different? In other words, are we still the same person if we change throughout our lives? “Yes,” says psychologist Alexandra Freund, “our sense of identity remains the same, even when we change completely – in fact, the more we change, the stronger this sense of self becomes.” That our identities change throughout our lives is an interesting paradox, the professor and chair of developmental psychology in adulthood at UZH explains.

When the seas get choppy

This partial rebuilding of our selves is driven by critical stages in our lives. At such turning points, we are no longer in calm and familiar waters. On the contrary, as the seas get choppy, our future is uncertain and our ship looks like it might even smash into the dangerous rocks ahead. It’s at times like these that we have to replace the most planks in our own ships – for instance when we leave school or start a new job, when we start a family, get divorced, move house, retire or lose someone dear to us. Or when we set ourselves new goals. Because our identity is also defined by who we want to be. “Setting new goals is often an opportunity to think about who we are and where we come from,” says Alexandra Freund.

But this introspection is capricious. While we all have an idea of who we are, the question of “who am I?” is far from easy to answer. Alexandra Freund discovered this herself when she put the question to elderly people for her thesis back in the mid-1990s. She had expected her interviewees to spout character traits, or to talk about their roles as parents, or their careers. In fact, most people were initially stumped by the question. “They came up with a few traits they associated with themselves, like being tidy or open-minded,” Freund recalls, “but hardly anyone mentioned any biographical details and yet they all had a distinct sense of identity.”

Strange indeed. Nothing is closer to us than ourselves, and yet the self is extremely elusive. “It’s not accessible to our direct experience,” says Freund, “the only way we can perceive ourselves is through self-objectification.” In other words, I observe myself almost as I observe others, only I have more information – feelings, thoughts, memories. The images we create of ourselves vary widely and depend heavily on the circumstances. Because we can never see ourselves and examine the attributes of our selves in a holistic way, only in parts. For example, at a job interview we would highlight different traits than we would to our friends or partner. “But this doesn’t mean that we’re lying, or trying to present an enhanced version of ourselves; rather, we are simply focusing on a different aspect of our lives,” the professor of psychology explains. Ultimately, there are as many selves as there are life contexts, says Freund.

My reflection in the mirror

But where does our self-concept come from in the first place? Staying with the Ship of Theseus: How and from what planks is it made? Developmental psychologists long considered the emergence of the human self as being the moment when a child first recognizes itself in the mirror, explains Moritz Daum. The psychologist researches how children and adolescents discover themselves and the world around them. But we now know that not only two-year-olds, but also crows, monkeys, ants and cleaner wrasses also pass this mirror test. And in experiments, psychologists have shown that our selves start to develop much earlier. Infants can already clearly distinguish between themselves and their environment. A newborn is able to tell whether it is touching itself or whether it is being touched by someone else. This shows that it already has an – albeit vague – bodily self-awareness. Looked at in this way, the development of the self and identity is an ongoing process that starts when we are born and only really ends when we die.

Once children recognize their reflections in the mirror, those around them increasingly become a sort of social mirror – first their parents, then their group of friends, classmates and teachers, and later work colleagues and superiors. They look to role models, emulate them, and distance themselves from them – and in this way, gradually form their own identities. In other words, we wouldn’t be who we are without other people. Parents can help their children in this process by being aware that they are role models and by taking this responsibility seriously. “If I make my child wear a cycle helmet, then I should wear one, too,” says Moritz Daum.

Does our DNA dictate who we are?

Role models remain crucial throughout our lives. Their influence is greatest in childhood, but even as adults we look up to people who have something we don’t. For psychology professor Moritz Daum, Welsh bass-baritone Bryn Terfel is precisely such a role model. “When he enters the stage, he exudes this spellbinding calm,” says Daum, who once wanted to become a singer himself, “I’d like to be able to give lectures with the same incredible composure as Bryn Terfel, but I’m not quite there yet.” But are role models, parents, friends and teachers really that important when it comes to developing our personalities? Isn’t this more down to our genes – the genetic blueprint in our DNA that determines, plank by plank as it were, who we will become? Scientists disagree on this. While there seemed to be a consensus on the nature-nurture debate that emerged in the 1990s, whereby our behavior is determined by our genes and the environment in equal measure, there is now a growing body of research that gives primacy to nature over nurture.

One of these studies was carried out by Richard Plomin. In his 2018 book Blueprint. How DNA Makes Us Who We Are, the British behavioral psychologist works on the assumption that it is primarily genes that determine identity. According to Plomin, whether we will be forthright or anxious people, whether we will be happy or sad, and whether we will achieve academic success is mainly decided by our genetic make-up. He believes that the influence of parents, friends and school on the development of our personalities and skills is overrated and is in fact much smaller than previously assumed.

Michael Shanahan from the Jacobs Center for Productive Youth Development at UZH has a different view. “Genes are molecules – presuming that molecules are largely responsible for my academic success is quite a bizarre idea,” he says. Shanahan is a social scientist, who has changed his own identity as a researcher. In his own words, he is a sociologist who became a biologist. His current research combines social sciences and biology in social genomics. Instead of pitting genes and environmental influences against each other, it is about looking at how biology and the environment interact when it comes to our development, explains Michael Shanahan, an American who has been researching and teaching at UZH since 2016. “Both the genetic code and our environment consist of information, and the way they interact influences human development,” says the social genomics expert.

The interface between biology and environment that Shanahan is referring to is what is known as epigenetics. It revolves around the question of how environmental influences such as stress lead to certain genes being activated or deactivated in our genomes. Social circumstances are also a significant determining factor. “We are exposed to stressors that activate parts of our genome, which in turn can influence our physical and mental development,” says Michael Shanahan. For example, permanent stress in childhood can make us behave more aggressively, but can also make us age more quickly, die sooner, and make us more likely to get sick.

What makes twins different?

Sociologist and geneticist Michael Shanahan believes our parents’ social status plays a key role in how we become who we are. This also has a crucial influence on epigenetics. “Children are sent on certain life paths, and these are heavily dependent on parents’ education, job and income,” he says. Social status is one of the most important influences in our lives, and has a significant impact on our epigenome. This means that genetically identical twins who grow up in very different households in terms of social status will become very different people with very different identities.

“We often hear in the media about how similar twins are,” says Shanahan, “but what we don’t tend to hear is that they can also be very different if they have grown up in completely different environments.” These differences affect both mental and cognitive development as well as health, because social status has an impact on epigenetics. How they do so and what the consequences are is the subject of one of Shanahan’s current research projects. There are indications that a low social status weakens people’s immune systems and leads to more inflammatory diseases, explains Shanahan.

Being like everyone else – but different

Besides the interaction between genes and the environment, Michael Shanahan believes there is another factor that shapes our identity: our life course – the path we take in life that makes us who we are. “On the one hand, we aspire to a legitimate path that conforms with society’s expectations and indicates a respectable life, while on the other, we want to be creative and different from other people,” says Shanahan. Reconciling these two sides is a challenge for all of us that we each have to tackle in our own way.

Alexandra Freund also assumes that our self-concept is heavily influenced by society’s expectations. “When we think about our identity at certain stages of life, we are most likely grappling with these sorts of expectations,” the psychologist explains. Someone just starting their first job at 35 is likely to experience negative reactions, for example. Because people generally try to avoid negative judgments, social expectations have a powerful influence on our behavior, says Freund.

So, over the course of our lives, we – more or less consciously – replace old or rotten planks with new ones, therefore changing our self-concept. Guided by past experiences, social expectations and our vision for the future, we arrange the thoughts, feelings and memories that make us who we are into the most coherent possible self at a given stage of life. “This self is made up of flexible elements – like attitudes and motivations – and more constant parts of our personality, which are probably more heavily influenced by our genes,” says Moritz Daum.

But our personalities can change, too. Introverted people, for example, can develop and practice strategies for dealing with their shyness that eventually allow them to project a confident self-image in front of an audience. In this way, we can keep renovating our ship throughout our lives – right down to the very last plank. And yet still stay the same: “A large part of our sense of identity comes from being able to see how we change,” says Alexandra Freund. In other words, I’m me precisely because I change.

Provided by University Of Zurich

Evolution in Action: New Plant Species at Urnerboden (Botany)

A new plant species named “Cardamine insueta” appeared in the region of Urnerboden in the Swiss alps, after the land has changed from forest to grassland over the last 150 years. The inheritance of two key traits from its parent plants enabled the newly emerged species to grow in a distinct environmental niche, as researches from the University of Zurich now show.

The land-use conversion from forest to grassland in “Urnerboden” induced the hybridization of the two progenitors generating the new species “Cardamine insueta”. (Bild: istock.com/Mathias Berger)

The emergence of a new species is generally thought to occur over long periods of time. But – as the example of the plant Cardamine insueta shows – evolution can also happen quite quickly. C. insueta, a new bittercress species first described in 1972, has only recently emerged in Urnerboden, a small alpine village in central Switzerland. It evolved just within the past 150 years due to environmental changes in the surrounding valley: when the local people cleared the forest and turned it into pasture land.

New plant species allows to observe “evolution in action”

“C. insueta proves to be an exceptional case to directly analyze the genetic traits and environmental responses of a new species. In other words: to observe ‘evolution in action’, a main topic of the university’s corresponding University Research Priority Program,” says Rie Shimizu-Inatsugi from the Department of Evolutionary Biology and Environmental Studies at the University of Zurich (UZH). The plant biologists were now able to unravel the genetic mechanisms underlying the plant’s evolution.

C. insueta developed from two parent species with specific ecological habitats: while C. amara grows in and beside water streams, C. rivularis inhabits slightly moist sites. The land-use conversion from forest to grassland induced the hybridization of the two progenitors generating the new species that is found in-between the parents’ habitats with temporal water level fluctuation. “It is the combination of genetic traits from its parents that enabled the new species to grow in a distinct environmental niche,” says Shimizu-Inatsugi. In fact, C. insueta inherited one set of chromosomes from C. amara and two sets of chromosomes from C. rivularis. It therefore contains three sets of chromosomes making it a so-called triploid plant.

Inheritance of two key parental traits enabled the survival

To characterize the responses to a fluctuating environment, the research team used high-throughput sequencing to analyze the time-course gene expression pattern of the three species in response to submergence. They found that the gene activity responsible for two parent traits were key for the survival of the new species in the novel habitat. First, C. insueta can clonally propagate through leaf vivipary, meaning it produces plantlets on the surface of leaves that can grow into new plants. It inherited the ability for asexual vegetative reproduction from C. rivularis. Since C. insueta is sexually sterile, it would not have been able to survive without this trait.

Second, C. insueta inherited the submergence tolerance from C. amara, since the genes responsible for this trait were active in both species. “The results show that C. insueta combined advantageous patterns of parental gene activity to contribute to its establishment in a new niche along a water-usage gradient. Depending on the environmental situation, the plant activates different set of genes it inherited from its two parent species.” says Rie Shimizu-Inatsugi.

References: Jianqiang Sun, Rie Shimizu-Inatsugi, Hugo Hofhuis, Kentaro Shimizu, Angela Hay, Kentaro K. Shimizu# and Jun Sese#. A Recently Formed Triploid Cardamine insueta Inherits Leaf Vivipary and Submergence Tolerance Traits of Parents. Frontiers in Genetics. 6 October 2020. DOI: 10.3389/fgene.2020.567262

Provided by University Of Zurich

High-Capacity Tape For Era Of Big Data (Computer Science)

Although out of sight to the majority of end users, data centers work behind the scenes to run the internet, businesses, research institutions and more. These data centers depend on high-capacity digital storage, the demand for which continues to accelerate. Researchers created a new storage medium and processes to access it that could prove game changing in this sector. Their material, called epsilon iron oxide, is also very robust so can be used in applications where long-term storage, such as archiving, is necessary.

A new magnetic material and recording process can vastly increase data capacity © University of Tokyo

It may seem odd to some that in the year 2020, magnetic tape is being discussed as a storage medium for digital data. After all, it has not been common in home computing since the 1980s. Surely the only relevant mediums today are solid state drives and Blu-ray discs? However, in data centers everywhere, at universities, banks, internet service providers or government offices, you will find that digital tapes are not only common, but essential.

Though they are slower to access than other storage devices, such as hard disk drives and solid state memory, digital tapes have very high storage densities. More information can be kept on a tape than other devices of similar sizes, and they can also be more cost effective too. So for data-intensive applications such as archives, backups and anything covered by the broad term big data, they are extremely important. And as demand for these applications increases, so does the demand for high-capacity digital tapes.

Magnetic pole flip. Millimeter waves irradiate epsilon iron oxide, reversing its magnetic states representing binary states 1 or 0. © 2020 Ohkoshi et al.

Professor Shin-ichi Ohkoshi from the Department of Chemistry at the University of Tokyo and his team have developed a magnetic material which, together with a special process to access it, can offer greater storage densities than ever. The robust nature of the material means that the data would last for longer than with other mediums, and the novel process operates at low power. As an added bonus, this system would also be very cheap to run.

“Our new magnetic material is called epsilon iron oxide, it is particularly suitable for long-term digital storage,” said Ohkoshi. “When data is written to it, the magnetic states that represent bits become resistant to external stray magnetic fields that might otherwise interfere with the data. We say it has a strong magnetic anisotropy. Of course, this feature also means that it is harder to write the data in the first place; however, we have a novel approach to that part of the process too.”

The recording process relies on high-frequency millimeter waves in the region of 30-300 gigahertz, or billions of cycles per second. These high frequency waves are directed at strips of epsilon iron oxide, which is an excellent absorber of such waves. When an external magnetic field is applied, the epsilon iron oxide allows its magnetic direction, which represents either a binary 1 or 0, to flip in the presence of the high-frequency waves. Once the tape has passed by the recording head where this takes place, the data is then locked into the tape until it is overwritten.

Data center. Digital tapes are very common in data centers. CC-3.0 Wikimedia Commons/Hannes Grobe

“This is how we overcome what is called in the data science field ‘the magnetic recording trilemma,’” said Project Assistant Professor Marie Yoshikiyo, from Ohkoshi’s laboratory. “The trilemma describes how, to increase storage density, you need smaller magnetic particles, but the smaller particles come with greater instability and the data can easily be lost. So we had to use more stable magnetic materials and produce an entirely new way to write to them. What surprised me was that this process could also be power efficient too.”

Epsilon iron oxide may also find uses beyond magnetic recording tape. The frequencies it absorbs well for recording purposes are also the frequencies that are intended for use in next-generation cellular communication technologies beyond 5G. So in the not too distant future when you are accessing a website on your 6G smartphone, both it and the data center behind the website may very well be making use of epsilon iron oxide.

“We knew early on that millimeter waves should theoretically be capable of flipping magnetic poles in epsilon iron oxide. But since it’s a newly observed phenomenon, we had to try various methods before finding one that worked,” said Ohkoshi. “Although the experiments were very difficult and challenging, the sight of the first successful signals was incredibly moving. I anticipate we will see magnetic tapes based on our new technology with 10 times the current capacities within five to 10 years.”

References: Shin-ichi Ohkoshi, Marie Yoshikiyo, Kenta Imoto, Kosuke Nakagawa, Asuka Namai, Hiroko Tokoro,Yuji Yahagi, Kyohei Takeuchi, Fangda Jia, Seiji Miyashita, Makoto Nakajima, Hongsong Qiu, Kosaku Kato, Takehiro Yamaoka, Masashi Shirata, Kenji Naoi, Koichi Yagishita, and Hiroaki Doshita, “Magnetic pole flip by millimeter wave,” Advanced Materials: October 8, 2020, doi:10.1002/adma.202004897 link: https://onlinelibrary.wiley.com/doi/10.1002/adma.202004897

Provided by University Of Tokyo

This Newly Developed Nanomaterial Can Act As A Precise Thermometer (Nanotechnology / Engineering)

A layered material developed by KAUST researchers can act as a precise temperature sensor by exploiting the same principle used in biological ion channels.

This SEM image shows an as-prepared lamellar membrane out of MXene before exposure to water/light/heat.© KAUST 2020

Human cells possess various proteins that act as channels for charged ions. In the skin, certain ion channels rely on heat to drive a flow of ions that generates electrical signals, which we use to sense the temperature of our surroundings.

Inspired by these biological sensors, KAUST researchers prepared a titanium carbide compound (Ti3C2Tx) known as an MXene, which contains multiple layers just a few atoms thick. Each layer is covered with negatively charged atoms, such as oxygen or fluorine. “These groups act as spacers to keep neighboring nanosheets apart, allowing water molecules to enter the interplanar channels,” says KAUST postdoc Seunghyun Hong, part of the team behind the new temperature sensor. The channels between the MXene layers are narrower than a single nanometer.

The researchers used techniques, such as X-ray diffraction and scanning electron microscopy, to investigate their MXene, and they found that adding water to the material slightly widened the channels between layers. When the material touched a solution of potassium chloride, these channels were large enough to allow positive potassium ions to move through the MXene, but blocked the passage of negative chloride ions.

A temperature difference between two ends of an MXene nanochannel causes water and potassium ions to flow from the cool side to the warm side (top). When sunlight heats just one part of an MXene device, a thermo-osmotic flow generates a voltage that can indicate tiny temperature changes (bottom). © 2020 ACS Nano; Alshareef, H.N. et al.

The team created a small device containing the MXene and exposed one end of it to sunlight. MXenes are particularly efficient at absorbing sunlight and converting that energy into heat. The resulting temperature rise prompted water molecules and potassium ions to flow through the nanochannels from the cooler end to the warmer part, an effect known as thermo-osmotic flow. This caused a voltage change comparable to that seen in biological temperature-sensing ion channels. As a result, the device could reliably sense temperature changes of less than one degree Celsius.

Decreasing the salinity of the potassium chloride solution improved the performance of the device, in part by further enhancing the channel’s selectivity for potassium ions.

As the researchers increased the intensity of light shining on the material, its temperature rose at the same rate, as did the ion-transporting response. This suggests that along with acting as a temperature sensor the material could also be used to measure light intensity.

The work was a result of collaboration between the groups of KAUST professors Husam Alshareef and Peng Wang. “We envision that the MXene cation channels have promise for many potential applications, including temperature sensing, photodetection or photothermoelectric energy harvesting,” says Alshareef, who co-led the team.

References: Hong, S., Zou, G., Kim, H., Huang, D., Wang, P. & Alshareef, H.N. Photothermoelectric response of Ti3C2Tx MXene confined ion channels. ACS Nano 14, 9042–9049 (2020). https://pubs.acs.org/doi/10.1021/acsnano.0c04099 doi: https://doi.org/10.1021/acsnano.0c04099

Provided by KAUST

Risk of Severe COVID May Depend on Your Type of Asthma, Experts Say (Medicine)

Everyone agrees about the good news — folks whose asthma is spurred on by allergies don’t appear to have an increased risk of life-threatening illness if they contract COVID-19.

“Asthma has not risen as one of the top comorbid diseases for worse COVID-19 outcomes,” said Dr. Sandhya Khurana, director of the Mary Parkes Center for Asthma, Allergy and Pulmonary Care at the University of Rochester (N.Y.) Medical Center. “We always worry with asthma and viral infections, because they seem to trigger asthma exacerbation unreasonably. But what we’ve seen so far is reassuring.”

But debate continues to swirl regarding the potential severity of COVID infection in people with non-allergic asthma.

©gettyimages

Some studies have suggested that people who have asthma caused by something other than allergies — exercise, stress, air pollution, weather conditions — might have an increased risk of severe COVID-19.

For example, Harvard researchers found that having non-allergic asthma increased the risk of severe COVID-19 by as much as 48%. That conclusion was based on data from 65,000 asthma sufferers presented in the June issue of the Journal of Allergy and Clinical Immunology.

“For those people, I think being more cautious would be good for them,” said senior researcher Liming Liang, an associate professor of statistical genetics at the Harvard T.H. Chan School of Public Health in Boston. “I think the next wave is coming. We’ve got to be more cautious.”

But other experts note that the data involving COVID and non-allergic asthma sufferers is very limited, and any conclusions that these folks are at higher risk of severe infection could be flawed.

Their asthma could be caused by other lung ailments that are associated with more serious cases of COVID, for instance, said Dr. Mitchell Grayson, chief of allergy and immunology at Nationwide Children’s Hospital in Columbus, Ohio.

“There have been several studies that have shown that COPD does increase your risk of more severe disease,” he said. “I don’t think these studies have done a good job of excluding COPD in these patients.”

Grayson agrees with Khurana that in the early days of the COVID-19 pandemic, there was much concern that asthma could be a risk factor — a reasonable suspicion, given that the coronavirus attacks the lungs.

But everything that came out of the initial epidemic in China suggested that asthma was not a risk factor for life-threatening COVID, Grayson said, and the data continued to confirm that as the coronavirus spread across the globe.

“It’s not there in the data. If it is there, it’s extremely small risk. It’s nothing I can see,” he said.

Researchers have speculated that people with allergy-driven asthma might have some protection against COVID, due to the way the coronavirus infects the body.

The SARS-CoV-2 virus that causes COVID-19 enters lung cells by engaging with a type of protein on their surface called an ACE2 receptor, Khurana said.

“In the setting of an allergic type of inflammation, the expression of the ACE2 receptor appears to be downregulated. It appears to be lower. There’s not as much receptor,” she said.

Because there aren’t as many ACE2 receptors available, people with allergic asthma might not be as vulnerable to severe infection, Khurana said. This theory also could help explain why other chronic diseases appear to increase COVID risk, she added.

“Patients in conditions like diabetes or hypertension, this receptor expression is increased,” Khurana said. “That’s a possible reason why those comorbid diseases are at especially high risk for this infection.”

But that only explains why allergic asthma isn’t a major risk factor for severe COVID, Grayson said. It doesn’t explain why some studies are finding increased risk among people with non-allergic asthma.

Grayson suspects that the purported link between non-allergic asthma and COVID found in these studies is actually a link between a COVID and a host of different lung ailments, especially COPD.

“There are studies showing that COPD increases your risk of more severe COVID, not markedly but a little bit, not to the extent of things like hypertension and diabetes and [being] elderly,” he said. “I’m concerned that what they’re calling non-allergic asthma actually is COPD, which would skew their data.”

In Khurana’s view, more study is needed, particularly prospective studies that track people with different types of asthma prior to COVID infection.

“So far, we just don’t know enough to make any conclusions. I think we’re still scratching the surface here and still have a lot to learn,” she said.

In the meantime, it would pay for everyone to protect themselves, Khurana added.

“It’s good practice to observe the recommended guidance on hand hygiene and social distancing and masking and avoiding any situation where you could be exposed, even though it’s obviously welcome to see that allergic asthma is not as high-risk as some of the other comorbid diseases,” Khurana said.

The First Robotic Theatre Of China Has Premiered, Utilizing Tsinghua Moja Robots (Engineering / Artificial Intelligence)

The first robotic theatre of China – the Legend of YingTian Gate – has premiered at the Site Museum of Yingtian Gate, Luoyang, Henan Province, on October 1st, 2020. Yingtian Gate was the main gate of the royal palace of the only empress of China, Wu Zetian, in Tang dynasty.

©Tsinghua University

The story of the theatre show is about an ancient craftsman living in the Tang dynasty, who engineered robotic puppets and dedicated them to the Empress for her coronation.

There were six robots and three human actors and actresses who participated in this theatre show. All the robots were designed and developed by an interdisciplinary team, led by Associate Professor Dr. Haipeng Mi. Besides the Chinese orchestra robots – the bamboo flute robot and the Chinese harp robot – three new robots were developed for this show. Newly introduced robot characters can even perform cross-talk. Compared to the previous performance, the robots in this newly developed theatre show have richer facial expressions and more delicate bodily movements.

As a new attempt to integrate robot performance and a stage show, this robotic theatre opens new possibilities for China’s cultural and creativity industries.

Provided by Tsinghua University

Hubble Captured Spectacular Image Of Iris Nebula (Astronomy)

This beautiful, blushing nebula is unique amongst its counterparts. While many of the nebulae visible in the night sky are emission nebulae — clouds of dust and gas that are hot enough to emit their own radiation and light — Caldwell 4, otherwise known as the Iris Nebula or NGC 7023, is a reflection nebula. This means that its color comes from the scattered light of its central star, which lies nestled in the abundant star fields of the constellation Cepheus. Located some 1,400 light-years away from Earth, the Iris Nebula’s glowing gaseous petals stretch roughly 6 light-years across.

Image Credit: NASA/ESA

This nebula is of particular interest to scientists because of its colors. Reflection nebulae glow because they are made up of extremely tiny particles of solid matter, up to 10 or even 100 times smaller than dust particles on Earth. These particles diffuse the light around them, giving the nebula a second-hand glow that’s typically bluish (like our sky). While the Iris Nebula appears predominantly blue, it includes large filaments of deep red, indicating the presence of an unknown chemical compound likely based on hydrocarbons. Studying nebulae like this one helps astronomers learn more about the ingredients that combine to make stars.

This close-up image, showing one rosy-colored region within Caldwell 4, is a composite of four exposures captured by Hubble’s Advanced Camera for Surveys in visible and near-infrared filters. Astronomers also studied the nebula with Hubble’s Near Infrared Camera and Multi-Object Spectrometer to determine which chemical elements are present in Caldwell 4.

Provided by NASA