Tag Archives: Spain

Get better protection from a sunscreen with a ‘flamenco dancing’ molecule?

Caption: illustrative image for the University of Warwick research on ‘Flamenco dancing’ molecule could lead to better-protecting sunscreen created by Dr. Michael Horbury. Credit:: created by Dr Michael Horbury

There are high hopes (more about why later) for a plant-based ‘flamenco dancing molecule’ and its inclusion in sunscreens as described in an October 18, 2019 University of Warwick press release (also on EurekAlert),

A molecule that protects plants from overexposure to harmful sunlight thanks to its flamenco-style twist could form the basis for a new longer-lasting sunscreen, chemists at the University of Warwick have found, in collaboration with colleagues in France and Spain. Research on the green molecule by the scientists has revealed that it absorbs ultraviolet light and then disperses it in a ‘flamenco-style’ dance, making it ideal for use as a UV filter in sunscreens.

The team of scientists report today, Friday 18th October 2019, in the journal Nature Communications that, as well as being plant-inspired, this molecule is also among a small number of suitable substances that are effective in absorbing light in the Ultraviolet A (UVA) region of wavelengths. It opens up the possibility of developing a naturally-derived and eco-friendly sunscreen that protects against the full range of harmful wavelengths of light from the sun.

The UV filters in a sunscreen are the ingredients that predominantly provide the protection from the sun’s rays. In addition to UV filters, sunscreens will typically also include:

Emollients, used for moisturising and lubricating the skin
Thickening agents
Emulsifiers to bind all the ingredients
Water
Other components that improve aesthetics, water resistance, etc.

The researchers tested a molecule called diethyl sinapate, a close mimic to a molecule that is commonly found in the leaves of plants, which is responsible for protecting them from overexposure to UV light while they absorb visible light for photosynthesis.

They first exposed the molecule to a number of different solvents to determine whether that had any impact on its (principally) light absorbing behaviour. They then deposited a sample of the molecule on an industry standard human skin mimic (VITRO-CORNEUM®) where it was irradiated with different wavelengths of UV light. They used the state-of-the-art laser facilities within the Warwick Centre for Ultrafast Spectroscopy to take images of the molecule at extremely high speeds, to observe what happens to the light’s energy when it’s absorbed in the molecule in the very early stages (millionths of millionths of a second). Other techniques were also used to establish longer term (many hours) properties of diethyl sinapate, such as endocrine disruption activity and antioxidant potential.

Professor Vasilios Stavros from the University of Warwick, Department of Chemistry, who was part of the research team, explains: “A really good sunscreen absorbs light and converts it to harmless heat. A bad sunscreen is one that absorbs light and then, for example, breaks down potentially inducing other chemistry that you don’t want. Diethyl sinapate generates lots of heat, and that’s really crucial.”

When irradiated the molecule absorbs light and goes into an excited state but that energy then has to be disposed of somehow. The team of researchers observed that it does a kind of molecular ‘dance’ a mere 10 picoseconds (ten millionths of a millionth of a second) long: a twist in a similar fashion to the filigranas and floreos hand movements of flamenco dancers. That causes it to come back to its original ground state and convert that energy into vibrational energy, or heat.

It is this ‘flamenco dance’ that gives the molecule its long-lasting qualities. When the scientists bombarded the molecule with UVA light they found that it degraded only 3% over two hours, compared to the industry requirement of 30%.

Dr Michael Horbury, who was a Postgraduate Research Fellow at The University Warwick when he undertook this research (and now at the University of Leeds) adds: “We have shown that by studying the molecular dance on such a short time-scale, the information that you gain can have tremendous repercussions on how you design future sunscreens.
Emily Holt, a PhD student in the Department of Chemistry at the University of Warwick who was part of the research team, said: “The next step would be to test it on human skin, then to mix it with other ingredients that you find in a sunscreen to see how those affect its characteristics.”

Professor Florent Allais and Dr Louis Mouterde, URD Agro-Biotechnologies Industrielles at AgroParisTech (Pomacle, France) commented: “What we have developed together is a molecule based upon a UV photoprotective molecule found in the surface of leaves on a plant and refunctionalised it using greener synthetic procedures. Indeed, this molecule has excellent long-term properties while exhibiting low endocrine disruption and valuable antioxidant properties.”

Professor Laurent Blasco, Global Technical Manager (Skin Essentials) at Lubrizol and Honorary Professor at the University of Warwick commented: “In sunscreen formulations at the moment there is a lack of broad-spectrum protection from a single UV filter. Our collaboration has gone some way towards developing a next generation broad-spectrum UV filter inspired by nature. Our collaboration has also highlighted the importance of academia and industry working together towards a common goal.”

Professor Vasilios Stavros added, “Amidst escalating concerns about their impact on human toxicity (e.g. endocrine disruption) and ecotoxicity (e.g. coral bleaching), developing new UV filters is essential. We have demonstrated that a highly attractive avenue is ‘nature-inspired’ UV filters, which provide a front-line defence against skin cancer and premature skin aging.”

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

Towards symmetry driven and nature inspired UV filter design by Michael D. Horbury, Emily L. Holt, Louis M. M. Mouterde, Patrick Balaguer, Juan Cebrián, Laurent Blasco, Florent Allais & Vasilios G. Stavros. Nature Communications volume 10, Article number: 4748 (2019) DOI: https://doi.org/10.1038/s41467-019-12719-z

This paper is open access.

Why the high hopes?

Briefly (the long story stretches over 10 years), the most recommended sunscreens today (2020) are ‘mineral-based’. This is painfully amusing because civil society groups (activists) such as Friends of the Earth (in particular the Australia chapter under Georgia Miller’s leadership) and Canada’s own ETC Group had campaigned against these same sunscreen when they were billed as being based on metal oxide nanoparticles such zinc oxide and/or titanium oxide. The ETC Group under Pat Roy Mooney’s leadership didn’t press the campaign after an initial push. As for Australia and Friend of the Earth, their anti-metallic oxide nanoparticle sunscreen campaign didn’t work out well as I noted in a February 9, 2012 posting and with a follow-up in an October 31, 2012 posting.

The only civil society group to give approval (very reluctantly) was the Environmental Working Group (EWG) as I noted in a July 9, 2009 posting. They had concerns about the fact that these ingredients are metallic but after a thorough of then available research, EWG gave the sunscreens a passing grade and noted, in their report, that they had more concerns about the use of oxybenzone in sunscreens. That latter concern has since been flagged by others (e.g., the state of Hawai’i) as noted in my July 6, 2018 posting.

So, rebranding metallic oxides as minerals has allowed the various civil society groups to support the very same sunscreens many of them were advocating against.

In the meantime, scientists continue work on developing plant-based sunscreens as an improvement to the ‘mineral-based’ sunscreens used now.

Neuronal regenerative-interfaces made of cross-linked carbon nanotube films

If I understand this research rightly, they are creating a film made of carbon nanotubes that can stimulate the growth of nerve cells (neurons) thus creating a ‘living/nonliving’ hybrid or as they call it in the press release a ‘biosynthetic hybrid’.

An August 2, 2019 news item on Nanowerk introduces the research (Note 1: There seem to be some translation issues; Note 2: Links have been removed),

Carbon nanotubes able to take on the desired shapes thanks to a special chemical treatment, called crosslinking and, at the same time, able to function as substrata for the growth of nerve cells, finely tuning their growth and activity.

The research published in ACS Nano (“Chemically Cross-Linked Carbon Nanotube Films Engineered to Control Neuronal Signaling”), is a new and important step towards the construction of neuronal regenerative-interfaces to repair spinal injuries.

The study is the new achievement of a long-term and, in terms of results, successful collaboration between the scientists Laura Ballerini of SISSA (Scuola Internazionale Superiore di Studi Avanzati), Trieste, and Maurizio Prato of the University of Trieste. The work team has also been assisted by CIC biomaGUNE of San Sebastián, Spain.

Caption: Carbon nanotubes able to take on the desired shapes thanks to a special chemical treatment, called crosslinking and, at the same time, able to function as substrata for the growth of nerve cells, finely tuning their growth and activity. Credit: Rossana Rauti

An August 2, 2019 SISSA press release (also on EurekAlert), which originated the news item, adds detail,

The carbon nanotubes used in the research have been modified by appropriate chemical treatments: “For many years, in our laboratories we have been working on the chemical reactivity of carbon nanotubes, a fascinating but very difficult material to work. Thanks to our experience, we have crosslinked them or, to say it more clearly, we have treated the nanotubes so they could link themselves to one another thanks to specific chemical reactions. We have discovered that this procedure gives the material very interesting characteristics. For example, the material organises itself in a stable manner according to a precise shape, we choose: a tissue where nerve cells need to be planted, for example. Or around some electrodes” explains Professor Prato. “We know from previous research that nerve cells grow well on carbon nanotubes so they could be used as a surface to build hybrid devices to regenerate nerve tissues. It was necessary to ensure that this chemical modification did not compromise this process and study whether the interaction with neurons was altered”.

Towards biosynthetic hybrids

Professor Ballerini continues: “We have discovered that the chemical process has important effects because through this treatment we can modulate the activity of neurons, in terms of growth, adhesion and survival. These materials can also regulate the communication between neurons. We can say that the carpet of crosslinked carbon nanotubes interacts intensely and constructively with the nerve cells”. This interaction depends on how much the different carbon nanotubes are linked to each other, or rather crosslinked. The lower the link number among the nanotubes the higher the activity of neurons that grow on their surface. Through the chemical control of their properties, and of the links between them, it is possible to regulate the response of the neurons. Ballerini and Prato explain: “This is an intriguing result that emerges from the important and fruitful collaboration between our research groups involving advanced research in chemistry, nanoscience and neurobiology . This study provides a further step in the design of future biosynthetic hybrids to recover injured nerve tissues functions”.

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

Chemically Cross-Linked Carbon Nanotube Films Engineered to Control Neuronal Signaling by Myriam Barrejón, Rossana Rauti, Laura Ballerini, Maurizio Prato. ACS Nano2019 XXXXXXXXXX-XXX Publication Date:July 22, 2019 DOI: https://doi.org/10.1021/acsnano.9b02429 Copyright © 2019 American Chemical Society

This paper is behind a paywall.

Good for your bones and good for art conservation: calcium

The statues on Easter Island, the Great Wall of China, Egyptian pyramids, MesoAmerican pyramids, castles in Europe and other structures made of stone are deteriorating and now comes another approach to halting the destruction. (I have covered other approaches to the problem in two previous postings, a December 5, 2017 posting, Europe’s cathedrals get a ‘lift’ with nanoparticles, and an October 21, 2014 posting, Heart of stone.)

An August 7, 2019 news item on ScienceDaily announces the latest in conserving stone monuments and structures,

When it comes to cultural heritage sites, there are few things historians wouldn’t do to preserve them for future generations. In particular, stone buildings and sculptures made of plaster and marble are increasingly at risk of damage from air pollution, acid rain and other factors. Researchers now report a new, calcium-based conservation treatment inspired by nature that overcomes many drawbacks of currently used methods.

An August 7, 2019 American Chemical Society (ACS) news release, which originated the news item, provides a bit more technical detail,

Historically, conservation scientists have turned to alkoxysilanes, silicon-based molecules used to consolidate stone and other artworks, in their preservation efforts. However, alkoxysilane treatments do not bond properly with non-silicate surfaces, are prone to cracking and are limited in their ability to repel water. Adding other compounds to this treatment have helped overcome these effects, but only to a point. Instead Encarnación Ruiz Agudo and colleagues looked to nature for inspiration, and found that calcium could be the answer. As a major element of strong, natural structures like bone and kidney stones, the researchers theorized that nanoparticles made from calcium could bolster alkoxysilanes and provide the desired protective effects to conserve historical artifacts.

The researchers made calcium carbonate and calcium oxalate nanoparticles and included polydimethylsiloxane (PDMS) as a stabilizer. PDMS also likely helps the nanoparticles bond to surfaces. The team added the nanoparticles to traditional alkoxysilane treatments, then applied them to samples of three different building materials: white marble, calcarenite limestone and gypsum plaster, and put the samples through a battery of tests. Overall, the results showed enhanced hydrophobicity, less cracking and improved surface adhesion compared to alkoxysilane treatments alone, with calcium oxalate providing a marked improvement in acid resistance. A minimal color effect was observed, but the researchers say this change was within acceptable values for conservation efforts.

The authors acknowledge funding from the European Regional Development Fund, the Regional Government of Andalusia, the Spanish Ministry of Economy and Finance and the University of Granada.

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

Bioinspired Alkoxysilane Conservation Treatments for Building Materials Based on Amorphous Calcium Carbonate and Oxalate Nanoparticles by A. Burgos-Cara, C. Rodríguez-Navarro, M. Ortega-Huertas, E. Ruiz-Agudo. ACS Appl. Nano Mater.2019XXXXXXXXXX-XXX DOI: https://doi.org/10.1021/acsanm.9b00905 Publication Date:July 18, 2019 Copyright © 2019 American Chemical Society

This paper is behind a paywall.

Membrane stretching as a new transport mechanism for nanomaterials

This work comes from Catalonia, Spain by way of a collaboration between Chinese, German, and, of course, Spanish scientists. From a December 12, 2018 Universitat Rovira i Virgili press release (also on EurekAlert),

Increasing awareness of bioeffects and toxicity of nanomaterials interacting with cells puts in focus the mechanisms by which nanomaterials can cross lipid membranes. Apart from well-discussed energy-dependent endocytosis for large objects and passive diffusion through membranes by solute molecules, there can exist other transport mechanisms based on physical principles. Based on this hypothesis, the team of theoretical physics at Universitat Rovira i Virgili in Tarragona, led by Dr. Vladimir Baulin, designed a research project to investigate the interaction between nanotube and lipid membranes. In computer simulations, the researchers studied what they call a “model bilayer”, composed only by one type of lipids. Based on their calculations, the team of Dr. Baulin observed that ultra -short nanotube (10nm length) can insert perpendicularly to the lipid bilayer core.

They observed that these nanotubes stay trapped in the cell membrane, as commonly accepted by the scientific community. But a surprise appears when they stretched their model cell membrane, then inserted nanotubes which were trapped in the bilayer, suddenly started to escape from the bilayer on both sides. This means that it is possible to control the transport of nanomaterial across a cell membrane by tuning the membrane tension.

This is where Dr. Baulin contacted Dr. Jean-Baptiste Fleury at the Saarland University (Germany) to confirm this mechanism and to study experimentally this tension-mediated transport phenomena. Dr. Fleury and his team, designed a microfluidic experiment with a well-controlled phospholipid bilayer, an experimental model for cell membranes and added ultra-small carbon nanotubes (10nm in length) in solution. The nanotubes had an adsorbed lipid monolayer that guarantees their stable dispersion and prevent their clustering. Using a combination of optical fluorescent microscopy and electrophysiological measurements, the team of Dr. Fleury could follow individual nanotube crossing a bilayer and unravel their pathway on a molecular level. And as predicted by the simulations, they observed that nanotubes inserted into the bilayer by dissolving their lipid coating into the artificial membrane. When a tension of 4mN/m was applied to the bilayer, nanotubes spontaneously escaped the bilayer just in few milliseconds, while at lower tensions nanotubes remain trapped inside the membrane.

This discovery of translocation of tiny nanotubes through barriers protecting cells, i.e. lipid bilayer, may raise concerns about safety of nanomaterials for public health and suggest new mechanical mechanisms to control the drug delivery.

Caption: Nanotubes trapped inside the membrane. Credit: © URV

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

Tension-Induced Translocation of an Ultrashort Carbon Nanotube through a Phospholipid Bilayer by Yachong Guo, Marco Werner, Ralf Seemann, Vladimir A. Baulin, and Jean-Baptiste Fleury. ACS Nano, Article ASAP DOI: 10.1021/acsnano.8b04657 Publication Date (Web): November 19, 2018

Copyright © 2018 American Chemical Society

This paper is behind a paywall.

Real-time tracking of UV (ultraviolet light) exposure for all skin types (light to dark)

It’s nice to find this research after my August 21, 2018 posting where I highlighted (scroll down to ‘Final comments’) the issues around databases and skin cancer data which is usually derived from fair-skinned people while people with darker hues tend not to be included. This is partly due to the fact that fair-skinned people have a higher risk and also partly due to myths about how more melanin in your skin somehow protects you from skin cancer.

This October 4, 2018 news item on ScienceDaily announces research into a way to track UV exposure for all skin types,

Researchers from the University of Granada [Spain] and RMIT University in Melbourne [Australia] have developed personalised and low-cost wearable ultraviolet (UV) sensors that warn users when their exposure to the sun has become dangerous.

The paper-based sensor, which can be worn as a wristband, features happy and sad emoticon faces — drawn in an invisible UV-sensitive ink — that successively light up as you reach 25%, 50%, 75% and finally 100% of your daily recommended UV exposure.

The research team have also created six versions of the colour-changing wristbands, each of which is personalised for a specific skin tone  [emphasis mine]– an important characteristic given that darker people need more sun exposure to produce vitamin D, which is essential for healthy bones, teeth and muscles.

An October 2, 2018 University of Granada press release (also on EurekAlert) delves further,

Four of the wristbands, each of which indicates a different stage of exposure to UV radiation (25%, 50%, 75% and 100%)

The emoticon faces on the wristband successively “light up” as exposure to UV radiation increases

Skin cancer, one of the most common types of cancer throughout the world, is primarily caused by overexposure to ultraviolet radiation (UVR). In Spain, over 74,000 people are diagnosed with non-melanoma skin cancer every year, while a further 4,000 are diagnosed with melanoma skin cancer. In regions such as Australia, where the ozone layer has been substantially depleted, it is estimated that approximately 2 in 3 people will be diagnosed with skin cancer by the time they reach the age of 70.

“UVB and UVC radiation is retained by the ozone layer. This sensor is especially important in the current context, given that the hole in the ozone layer is exposing us to such dangerous radiation”, explains José Manuel Domínguez Vera, a researcher at the University of Granada’s Department of Inorganic Chemistry and the main author of the paper.

Domínguez Vera also highlights that other sensors currently available on the market only measure overall UV radiation, without distinguishing between UVA, UVB and UVC, each of which has a significantly different impact on human health.  In contrast, the new paper-based sensor can differentiate between UVA, UVB and UVC radiation. Prolonged exposure to UVA radiation is associated with skin ageing and wrinkling, while excessive exposure to UVB causes sunburn and increases the likelihood of skin cancer and eye damage.

Drawbacks of the traditional UV index

Ultraviolet radiation is determined by aspects such as location, time of day, pollution levels, astronomical factors, weather conditions such as clouds, and can be heightened by reflective surfaces like bodies of water, sand and snow. But UV rays are not visible to the human eye (even if it is cloudy UV radiation can be high) and until now the only way of monitoring UV intensity has been to use the UV index, which is standardly given in weather reports and indicates 5 degrees of radiation;  low, moderate, high, very high or extreme.

Despite its usefulness, the UV index is a relatively limited tool. For instance, it does not clearly indicate what time of the day or for how long you should be outside to get your essential vitamin D dose, or when to cover up to avoid sunburn and a heightened risk of skin cancer.

Moreover, the UV index is normally based on calculations for fair skin, making it unsuitable for ethnically diverse populations.  While individuals with fairer skin are more susceptible to UV damage, those with darker skin require much longer periods in the sun in order to absorb healthy amounts of vitamin D. In this regard, the UV index is not an accurate tool for gauging and monitoring an individual’s recommended daily exposure.

UV-sensitive ink

The research team set out to tackle the drawbacks of the traditional UV index by developing an inexpensive, disposable and personalised sensor that allows the wearer to track their UV exposure in real-time. The sensor paper they created features a special ink, containing phosphomolybdic acid (PMA), which turns from colourless to blue when exposed to UV radiation. They can use the initially-invisible ink to draw faces—or any other design—on paper and other surfaces. Depending on the type and intensity of the UV radiation to which the ink is exposed, the paper begins to turn blue; the greater the exposure to UV radiation, the faster the paper turns blue.

Additionally, by tweaking the ink composition and the sensor design, the team were able to make the ink change colour faster or slower, allowing them to produce different sensors that are tailored to the six different types of skin colour. [emphasis mine]

Applications beyond health

This low-cost, paper-based sensor technology will not only help people of all colours to strike an optimum balance between absorbing enough vitamin D and avoiding sun damage — it also has significant applications for the agricultural and industrial sectors. UV rays affect the growth of crops and the shelf life of a range of consumer products. As the UV sensors can detect even the slightest doses of UV radiation, as well as the most extreme, this new technology could have vast potential for industries and companies seeking to evaluate the prolonged impact of UV exposure on products that are cultivated or kept outdoors.

The research project is the result of fruitful collaborations between two members of the UGR BIONanoMet (FQM368) research group; Ana González and José Manuel Domínguez-Vera, and the research group led by Dr. Vipul Bansal at RMIT University in Melbourne (Australia).

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

Skin color-specific and spectrally-selective naked-eye dosimetry of UVA, B and C radiations by Wenyue Zou, Ana González, Deshetti Jampaiah, Rajesh Ramanathan, Mohammad Taha, Sumeet Walia, Sharath Sriram, Madhu Bhaskaran, José M. Dominguez-Vera, & Vipul Bansal. Nature Communicationsvolume 9, Article number: 3743 (2018) DOI: https://doi.org/10.1038/s41467-018-06273-3 Published 25 September 2018

This paper is open access.

A biotech talk: Re – [Generating, Creating, Interpreting] on Tuesday, April 30, 2019 at 5:30 pm in Toronto, Ontario (Canada)

[downloaded from https://artscisalon.com/re-generating-creating-interpreting-tuesday-april-30-530-pm-ocadu/]

This image is intriguing as it’s being used to illustrate an ArtSci Salon April 30, 2019 event about biotechnology (from the Re – [Generating, Creating, Interpreting] event webpage),

Re – [Generating, Creating, Interpreting]

Conversations about Life

We live in strange times. We mourn for the countless lives we are losing to extinction, famine, severe weather and disease; we celebrate the possibility that science may assist us in preserving what we have and in regenerating what is no more. We aspire to re-create long gone species and proceed to create new one. Biotechnologies both terrify and invigorate us. We are torn between creating risk free futures and taking exciting Promethean risks. We claim that biotech can create a more democratic society; yet, we are increasingly racist, sexist and classist.

What’s at stake? How can life unfold from here? How do we reinterpret and re-imagine it? Join us for a series of brief presentations and a following juicy discussion. There will be refreshments. …And juice

With:

Joana Magalhães
Institute of Biomedical Research, A Coruña (INIBIC)

Polona Tratnik
Research Institute for Humanities, Alma Mater Europaea, Ljubljana

Roberta Buiani
Centre for Feminist Research, York University, Toronto

Moderated by:

Dolores Steinman
Biomedical Simulation Lab (BSL)

Tuesday, April 30
5.30 pm

OCADU (Ontario College of Art and Design University)
DF Salon, Room 701K  (7th floor)
205 Richmond St W

RSVP  https://www.facebook.com/events/811144362603498/

For the curious, here are the bios (also from the Re – [Generating, Creating, Interpreting] event webpage),

Roberta Buiani (PhD Communication and Culture, YorkU) is an interdisciplinary artist, media scholar and curator based in Toronto. She is the co-founder of the ArtSci Salon at the Fields Institute for Research in Mathematical Sciences (Toronto) and co-organizer of LASER Toronto. Her recent SSHRC-funded research creation project draws on feminist technoscience and on collaborative encounters across the sciences and the arts to investigate emerging life forms exceeding the categories defined by traditional methods of classification. Her artistic work has travelled to art festivals (Transmediale; Hemispheric Institute Encuentro; Brazil), community centres and galleries (the Free Gallery Toronto; Immigrant Movement International, Queens, Myseum of Toronto), and science institutions (RPI; the Fields Institute). Her writing has appeared on Space and Culture, Cultural Studies and The Canadian Journal of Communication among others. With the ArtSci Salon she has launched a series of experiments in “squatting academia”, by re-populating abandoned spaces and cabinets across university campuses with SciArt installations. Currently, she is a research associate at the Centre for Feminist Research at York University. ArtSci Salon website: https://artscisalon.com Personal http://atomarborea.net

Joana Magalhães holds a B.Sc. in Biology and a Ph.D. in Biochemistry and Molecular Biology. She is a Postdoctoral Researcher at the Institute of Biomedical Research of A Coruña, Spain, working in the field of regenerative medicine strategies for osteoarthritis. Previous positions include a Postdoctoral Fellowship at the Spanish Networking Biomedical Center and a Marie Curie PhD Fellowship at the Spanish Council for Scientific Research. In parallel with her scientific career, she develops STEAM-for-health media strategies from a gender perspective that received several national and international awards (Science on Stage 2017 for Radio, Press and TV or SCI-DOC Festival Mention of honour Women in Science Category 2018). Currently, she is Correspondent for “Women in Science” at Efervesciencia Radio Program. Moreover, she was a scientist-in-residence at Fundación Luis Seoane and Artesacía Theatrical Company for “TRANSCÉNICA” – I Transmedia Creators Meeting (2015). She is the Spanish Representative at the Young Scientist Forum – European Society of Biomaterials and Board Member of the Association of Women in Science and Technology (AMIT) – Galician Node. http://jomagellan.tumblr.com

Dolores Steinman Biomedical Simulation Lab, University of Toronto.

Dr. Steinman’s involvement with the Biomedical Simulation Laboratory (BSL), at the University of Toronto, is based on her experience as an MD (Romania) and PhD in Cell Biology (Canada) that led her to contribute in situating the BSL’s “patient-specific” computer-based simulations in the socio-historical, ethical and aesthetic context of medical imaging and imagery.

Polona Tratnik, Ph.D., is Dean of Alma Mater Europaea – Institutum Studiorum Humanitatis, Faculty and Research Institute for Humanities, Ljubljana [Slovenia], where she is a Professor and Head of Research as well. She also teaches courses at the Faculty for Media and Communication at Singidunum University in Serbia, at the Academy of Fine Arts and Design of the University of Ljubljana, at the Faculty of Education of the University of Maribor and at the Faculty for Design of the University of Primorska. She used to be the Head of the Department for Cultural Studies at the Faculty for Humanities of the University of Primorska. In 2012 she was a Fulbright Visiting Scholar, as well as a Guest Professor at the University of California Santa Cruz. She was a Guest Professor also at the Capital Normal University Bejing (China), at the Faculty for Art and Design Helsinki TAIK (Finland), and at the Universidad Nacional Autónoma de México(Mexico City). She is president of the Slovenian Society of Aesthetics (since 2011) and an Executive Committee Member of the International Association of Aesthetics. She has authored seven monographs and one proceeding as single author, including the Hacer-vivir más allá del cuerpo y del medio (Mexico City: Herder, 2013), Art as Intervention(Sophia, 2017) and Conquest of Body. Biopower with Biotechnology (Springer, 2017). Polona Tratnik is a pioneer bio artist exhibiting worldwide at shows such as Ars Electronica festival and BEAP festival in Perth .http://www.polona-tratnik.si

It should be a stimulating discussion although I am curious as to about omission from this list: “… biotech can create a more democratic society; yet, we are increasingly racist, sexist and classist. ” What about age or, more specifically, ageism? Maybe next time, eh?

Human lung enzyme can degrade graphene

Caption: A human lung enzyme can biodegrade graphene. Credit: Fotolia Courtesy: Graphene Flagship

The big European Commission research programme, Grahene Flagship, has announced some new work with widespread implications if graphene is to be used in biomedical implants. From a August 23, 2018 news item on ScienceDaily,

Myeloperoxidase — an enzyme naturally found in our lungs — can biodegrade pristine graphene, according to the latest discovery of Graphene Flagship partners in CNRS, University of Strasbourg (France), Karolinska Institute (Sweden) and University of Castilla-La Mancha (Spain). Among other projects, the Graphene Flagship designs based like flexible biomedical electronic devices that will interfaced with the human body. Such applications require graphene to be biodegradable, so our body can be expelled from the body.

An August 23, 2018 Grapehene Flagship press release (mildly edited version on EurekAlert), which originated the news item, provides more detail,

To test how graphene behaves within the body, researchers analysed how it was broken down with the addition of a common human enzyme – myeloperoxidase or MPO. If a foreign body or bacteria is detected, neutrophils surround it and secrete MPO, thereby destroying the threat. Previous work by Graphene Flagship partners found that MPO could successfully biodegrade graphene oxide.

However, the structure of non-functionalized graphene was thought to be more resistant to degradation. To test this, the team looked at the effects of MPO ex vivo on two graphene forms; single- and few-layer.

Alberto Bianco, researcher at Graphene Flagship Partner CNRS, explains: “We used two forms of graphene, single- and few-layer, prepared by two different methods in water. They were then taken and put in contact with myeloperoxidase in the presence of hydrogen peroxide. This peroxidase was able to degrade and oxidise them. This was really unexpected, because we thought that non-functionalized graphene was more resistant than graphene oxide.”

Rajendra Kurapati, first author on the study and researcher at Graphene Flagship Partner CNRS, remarks how “the results emphasize that highly dispersible graphene could be degraded in the body by the action of neutrophils. This would open the new avenue for developing graphene-based materials.”

With successful ex-vivo testing, in-vivo testing is the next stage. Bengt Fadeel, professor at Graphene Flagship Partner Karolinska Institute believes that “understanding whether graphene is biodegradable or not is important for biomedical and other applications of this material. The fact that cells of the immune system are capable of handling graphene is very promising.”

Prof. Maurizio Prato, the Graphene Flagship leader for its Health and Environment Work Package said that “the enzymatic degradation of graphene is a very important topic, because in principle, graphene dispersed in the atmosphere could produce some harm. Instead, if there are microorganisms able to degrade graphene and related materials, the persistence of these materials in our environment will be strongly decreased. These types of studies are needed.” “What is also needed is to investigate the nature of degradation products,” adds Prato. “Once graphene is digested by enzymes, it could produce harmful derivatives. We need to know the structure of these derivatives and study their impact on health and environment,” he concludes.

Prof. Andrea C. Ferrari, Science and Technology Officer of the Graphene Flagship, and chair of its management panel added: “The report of a successful avenue for graphene biodegradation is a very important step forward to ensure the safe use of this material in applications. The Graphene Flagship has put the investigation of the health and environment effects of graphene at the centre of its programme since the start. These results strengthen our innovation and technology roadmap.”

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

Degradation of Single‐Layer and Few‐Layer Graphene by Neutrophil Myeloperoxidase by Dr. Rajendra Kurapati, Dr. Sourav P. Mukherjee, Dr. Cristina Martín, Dr. George Bepete, Prof. Ester Vázquez, Dr. Alain Pénicaud, Prof. Dr. Bengt Fadeel, Dr. Alberto Bianco. Angewandte Chemie https://doi.org/10.1002/anie.201806906 First published: 13 July 2018

This paper is behind a paywall.

Neurons and graphene carpets

I don’t entirely grasp the carpet analogy. Actually, I have no why they used a carpet analogy but here’s the June 12, 2018 ScienceDaily news item about the research,

A work led by SISSA [Scuola Internazionale Superiore di Studi Avanzati] and published on Nature Nanotechnology reports for the first time experimentally the phenomenon of ion ‘trapping’ by graphene carpets and its effect on the communication between neurons. The researchers have observed an increase in the activity of nerve cells grown on a single layer of graphene. Combining theoretical and experimental approaches they have shown that the phenomenon is due to the ability of the material to ‘trap’ several ions present in the surrounding environment on its surface, modulating its composition. Graphene is the thinnest bi-dimensional material available today, characterised by incredible properties of conductivity, flexibility and transparency. Although there are great expectations for its applications in the biomedical field, only very few works have analysed its interactions with neuronal tissue.

A June 12, 2018 SISSA press release (also on EurekAlert), which originated the news item, provides more detail,

A study conducted by SISSA – Scuola Internazionale Superiore di Studi Avanzati, in association with the University of Antwerp (Belgium), the University of Trieste and the Institute of Science and Technology of Barcelona (Spain), has analysed the behaviour of neurons grown on a single layer of graphene, observing a strengthening in their activity. Through theoretical and experimental approaches the researchers have shown that such behaviour is due to reduced ion mobility, in particular of potassium, to the neuron-graphene interface. This phenomenon is commonly called ‘ion trapping’, already known at theoretical level, but observed experimentally for the first time only now. “It is as if graphene behaves as an ultra-thin magnet on whose surface some of the potassium ions present in the extra cellular solution between the cells and the graphene remain trapped. It is this small variation that determines the increase in neuronal excitability” comments Denis Scaini, researcher at SISSA who has led the research alongside Laura Ballerini.

The study has also shown that this strengthening occurs when the graphene itself is supported by an insulator, like glass, or suspended in solution, while it disappears when lying on a conductor. “Graphene is a highly conductive material which could potentially be used to coat any surface. Understanding how its behaviour varies according to the substratum on which it is laid is essential for its future applications, above all in the neurological field” continues Scaini, “considering the unique properties of graphene it is natural to think for example about the development of innovative electrodes of cerebral stimulation or visual devices”.

It is a study with a double outcome. Laura Ballerini comments as follows: “This ‘ion trap’ effect was described only in theory. Studying the impact of the ‘technology of materials’ on biological systems, we have documented a mechanism to regulate membrane excitability, but at the same time we have also experimentally described a property of the material through the biology of neurons.”

Dexter Johnson in a June 13, 2018 posting, on his Nanoclast blog (on the IEEE [Institute of Electrical and Electronics Engineers] website), provides more context for the work (Note: Links have been removed),

While graphene has been tapped to deliver on everything from electronics to optoelectronics, it’s a bit harder to picture how it may offer a key tool for addressing neurological damage and disorders. But that’s exactly what researchers have been looking at lately because of the wonder material’s conductivity and transparency.

In the most recent development, a team from Europe has offered a deeper understanding of how graphene can be combined with neurological tissue and, in so doing, may have not only given us an additional tool for neurological medicine, but also provided a tool for gaining insights into other biological processes.

“The results demonstrate that, depending on how the interface with [single-layer graphene] is engineered, the material may tune neuronal activities by altering the ion mobility, in particular potassium, at the cell/substrate interface,” said Laura Ballerini, a researcher in neurons and nanomaterials at SISSA.

Ballerini provided some context for this most recent development by explaining that graphene-based nanomaterials have come to represent potential tools in neurology and neurosurgery.

“These materials are increasingly engineered as components of a variety of applications such as biosensors, interfaces, or drug-delivery platforms,” said Ballerini. “In particular, in neural electrode or interfaces, a precise requirement is the stable device/neuronal electrical coupling, which requires governing the interactions between the electrode surface and the cell membrane.”

This neuro-electrode hybrid is at the core of numerous studies, she explained, and graphene, thanks to its electrical properties, transparency, and flexibility represents an ideal material candidate.

In all of this work, the real challenge has been to investigate the ability of a single atomic layer to tune neuronal excitability and to demonstrate unequivocally that graphene selectively modifies membrane-associated neuronal functions.

I encourage you to read Dexter’s posting as it clarifies the work described in the SISSA press release for those of us (me) who may fail to grasp the implications.

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

Single-layer graphene modulates neuronal communication and augments membrane ion currents by Niccolò Paolo Pampaloni, Martin Lottner, Michele Giugliano, Alessia Matruglio, Francesco D’Amico, Maurizio Prato, Josè Antonio Garrido, Laura Ballerini, & Denis Scaini. Nature Nanotechnology (2018) DOI: https://doi.org/10.1038/s41565-018-0163-6 Published online June 13, 2018

This paper is behind a paywall.

All this brings to mind a prediction made about the Graphene Flagship and the Human Brain Project shortly after the European Commission announced in January 2013 that each project had won funding of 1B Euros to be paid out over a period of 10 years. The prediction was that scientists would work on graphene/human brain research.

The sound of frogs (and other amphibians) and climate change

At least once a year I highlight some work about frogs. It’s usually about a new species but this time, it’s all about frog sounds (as well as, sounds from other amphibians).

Caption: The calls of the midwife toad and other amphibians have served to test the sound classifier. Credit: Jaime Bosch (MNCN-CSIC)

In any event, here’s more from an April 30, 2018 Spanish Foundation for Science and Technology (FECYT) press release (also on EurekAlert but with a May 17, 2018 publication date),

The sounds of amphibians are altered by the increase in ambient temperature, a phenomenon that, in addition to interfering with reproductive behaviour, serves as an indicator of global warming. Researchers at the University of Seville have resorted to artificial intelligence to create an automatic classifier of the thousands of frog and toad sounds that can be recorded in a natural environment.

One of the consequences of climate change is its impact on the physiological functions of animals, such as frogs and toads with their calls. Their mating call, which plays a crucial role in the sexual selection and reproduction of these amphibians, is affected by the increase in ambient temperature.

When this exceeds a certain threshold, the physiological processes associated with the sound production are restricted, and some calls are even actually inhibited. In fact, the beginning, duration and intensity of calls from the male to the female are changed, which influences reproductive activity.

Taking into account this phenomenon, the analysis and classification of the sounds produced by certain species of amphibians and other animals have turned out to be a powerful indicator of temperature fluctuations and, therefore, of the existence and evolution of global warming.

To capture the sounds of frogs, networks of audio sensors are placed and connected wirelessly in areas that can reach several hundred square kilometres. The problem is that a huge amount of bio-acoustic information is collected in environments as noisy as a jungle, and this makes it difficult to identify the species and their calls.

To solve this, engineers from the University of Seville have resorted to artificial intelligence. “We’ve segmented the sound into temporary windows or audio frames and have classified them by means of decision trees, an automatic learning technique that is used in computing”, explains Amalia Luque Sendra, co-author of the work.

To perform the classification, the researchers have based it on MPEG-7 parameters and audio descriptors, a standard way of representing audiovisual information. The details are published in Expert Systems with Applications magazine.

This technique has been put to the test with real sounds of amphibians recorded in the middle of nature and provided by the National Museum of Natural Sciences. More specifically, 868 records with 369 mating calls sung by the male and 63 release calls issued by the female natterajck toad (Epidalea calamita), along with 419 mating calls and 17 distress calls of the common midwife toad (Alytesobstetricans).

“In this case we obtained a success rate close to 90% when classifying the sounds,” observes Luque Sendra, who recalls that, in addition to the types of calls, the number of individuals of certain amphibian species that are heard in a geographical region over time can also be used as an indicator of climate change.

“A temperature increase affects the calling patterns,” she says, “but since these in most cases have a sexual calling nature, they also affect the number of individuals. With our method, we still can’t directly determine the exact number of specimens in an area, but it is possible to get a first approximation.”

In addition to the image of the midwife toad, the researchers included this image to illustrate their work,

Caption: This is the architecture of a wireless sensor network. Credit: J. Luque et al./Sensors

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

Non-sequential automatic classification of anuran sounds for the estimation of climate-change indicators by Amalia Luque, Javier Romero-Lemos, Alejandro Carrasco, Julio Barbancho. Expert Systems with Applications Volume 95, 1 April 2018, Pages 248-260 DOI: https://doi.org/10.1016/j.eswa.2017.11.016 Available online 10 November 2017

This paper is open access.

Santiago Ramón y Cajal and the butterflies of the soul

The Cajal exhibit of drawings was here in Vancouver (Canada) this last fall (2017) and I still carry the memory of that glorious experience (see my Sept. 11, 2017 posting for more about the show and associated events). It seems Cajal’s drawings had a similar response in New York city, from a January 18, 2018 article by Roberta Smith for the New York Times,

It’s not often that you look at an exhibition with the help of the very apparatus that is its subject. But so it is with “The Beautiful Brain: The Drawings of Santiago Ramón y Cajal” at the Grey Art Gallery at New York University, one of the most unusual, ravishing exhibitions of the season.

The show finished its run on March 31, 2018 and is now on its way to the Massachusetts Institute of Technology (MIT) in Boston, Massachusetts for its opening on May 3, 2018. It looks like they have an exciting lineup of events to go along with the exhibit (from MIT’s The Beautiful Brain: The Drawings of Santiago Ramón y Cajal exhibit and event page),

SUMMER PROGRAMS

ONGOING

Spotlight Tours
Explorations led by local and Spanish scientists, artists, and entrepreneurs who will share their unique perspectives on particular aspects of the exhibition. (2:00 pm on select Tuesdays and Saturdays)

Tue, May 8 – Mark Harnett, Fred and Carole Middleton Career Development Professor at MIT and McGovern Institute Investigator Sat, May 26 – Marion Boulicault, MIT Graduate Student and Neuroethics Fellow in the Center for Sensorimotor Neural Engineering Tue, June 5 – Kelsey Allen, Graduate researcher, MIT Center for Brains, Minds, and Machines Sat, Jun 23 – Francisco Martin-Martinez, Research Scientist in MIT’s Laboratory for Atomistic & Molecular Mechanics and President of the Spanish Foundation for Science and Technology Jul 21 – Alex Gomez-Marin, Principal Investigator of the Behavior of Organisms Laboratory in the Instituto de Neurociencias, Spain Tue, Jul 31– Julie Pryor, Director of Communications at the McGovern Institute for Brain Research at MIT Tue, Aug 28 – Satrajit Ghosh, Principal Research Scientist at the McGovern Institute for Brain Research at MIT, Assistant Professor in the Department of Otolaryngology at Harvard Medical School, and faculty member in the Speech and Hearing Biosciences and Technology program in the Harvard Division of Medical Sciences

Idea Hub
Drop in and explore expansion microscopy in our maker-space.

Visualizing Science Workshop
Experiential learning with micro-scale biological images. (pre-registration required)

Gallery Demonstrations
Researchers share the latest on neural anatomy, signal transmission, and modern imaging techniques.

EVENTS

Teen Science Café: Mindful Matters
MIT researchers studying the brain share their mind-blowing findings.

Neuron Paint Night
Create a painting of cerebral cortex neurons and learn about the EyeWire citizen science game.

Cerebral Cinema Series
Hear from researchers and then compare real science to depictions on the big screen.

Brainy Trivia
Test your brain power in a night of science trivia and short, snappy research talks.

Come back to see our exciting lineup for the fall!

If you don’t have a chance to see the show or if you’d like a preview, I encourage you to read Smith’s article as it has embedded several Cajal drawings and rendered them exceptionally well.

For those who like a little contemporary (and related) science with their art, there’s a March 30, 2018 Harvard Medical Schoo (HMS)l news release by Kevin Jang (also on EurekAlert), Note: All links save one have been removed,

Drawing of the cells of the chick cerebellum by Santiago Ramón y Cajal, from “Estructura de los centros nerviosos de las aves,” Madrid, circa 1905

 

Modern neuroscience, for all its complexity, can trace its roots directly to a series of pen-and-paper sketches rendered by Nobel laureate Santiago Ramón y Cajal in the late 19th and early 20th centuries.

His observations and drawings exposed the previously hidden composition of the brain, revealing neuronal cell bodies and delicate projections that connect individual neurons together into intricate networks.

As he explored the nervous systems of various organisms under his microscope, a natural question arose: What makes a human brain different from the brain of any other species?

At least part of the answer, Ramón y Cajal hypothesized, lay in a specific class of neuron—one found in a dazzling variety of shapes and patterns of connectivity, and present in higher proportions in the human brain than in the brains of other species. He dubbed them the “butterflies of the soul.”

Known as interneurons, these cells play critical roles in transmitting information between sensory and motor neurons, and, when defective, have been linked to diseases such as schizophrenia, autism and intellectual disability.

Despite more than a century of study, however, it remains unclear why interneurons are so diverse and what specific functions the different subtypes carry out.

Now, in a study published in the March 22 [2018] issue of Nature, researchers from Harvard Medical School, New York Genome Center, New York University and the Broad Institute of MIT and Harvard have detailed for the first time how interneurons emerge and diversify in the brain.

Using single-cell analysis—a technology that allows scientists to track cellular behavior one cell at a time—the team traced the lineage of interneurons from their earliest precursor states to their mature forms in mice. The researchers identified key genetic programs that determine the fate of developing interneurons, as well as when these programs are switched on or off.

The findings serve as a guide for efforts to shed light on interneuron function and may help inform new treatment strategies for disorders involving their dysfunction, the authors said.

“We knew more than 100 years ago that this huge diversity of morphologically interesting cells existed in the brain, but their specific individual roles in brain function are still largely unclear,” said co-senior author Gordon Fishell, HMS professor of neurobiology and a faculty member at the Stanley Center for Psychiatric Research at the Broad.

“Our study provides a road map for understanding how and when distinct interneuron subtypes develop, giving us unprecedented insight into the biology of these cells,” he said. “We can now investigate interneuron properties as they emerge, unlock how these important cells function and perhaps even intervene when they fail to develop correctly in neuropsychiatric disease.”

A hippocampal interneuron. Image: Biosciences Imaging Gp, Soton, Wellcome Trust via Creative CommonsA hippocampal interneuron. Image: Biosciences Imaging Gp, Soton, Wellcome Trust via Creative Commons

Origins and Fates

In collaboration with co-senior author Rahul Satija, core faculty member of the New York Genome Center, Fishell and colleagues analyzed brain regions in developing mice known to contain precursor cells that give rise to interneurons.

Using Drop-seq, a single-cell sequencing technique created by researchers at HMS and the Broad, the team profiled gene expression in thousands of individual cells at multiple time points.

This approach overcomes a major limitation in past research, which could analyze only the average activity of mixtures of many different cells.

In the current study, the team found that the precursor state of all interneurons had similar gene expression patterns despite originating in three separate brain regions and giving rise to 14 or more interneuron subtypes alone—a number still under debate as researchers learn more about these cells.

“Mature interneuron subtypes exhibit incredible diversity. Their morphology and patterns of connectivity and activity are so different from each other, but our results show that the first steps in their maturation are remarkably similar,” said Satija, who is also an assistant professor of biology at New York University.

“They share a common developmental trajectory at the earliest stages, but the seeds of what will cause them to diverge later—a handful of genes—are present from the beginning,” Satija said.

As they profiled cells at later stages in development, the team observed the initial emergence of four interneuron “cardinal” classes, which give rise to distinct fates. Cells were committed to these fates even in the early embryo. By developing a novel computational strategy to link precursors with adult subtypes, the researchers identified individual genes that were switched on and off when cells began to diversify.

For example, they found that the gene Mef2c—mutations of which are linked to Alzheimer’s disease, schizophrenia and neurodevelopmental disorders in humans—is an early embryonic marker for a specific interneuron subtype known as Pvalb neurons. When they deleted Mef2c in animal models, Pvalb neurons failed to develop.

These early genes likely orchestrate the execution of subsequent genetic subroutines, such as ones that guide interneuron subtypes as they migrate to different locations in the brain and ones that help form unique connection patterns with other neural cell types, the authors said.

The identification of these genes and their temporal activity now provide researchers with specific targets to investigate the precise functions of interneurons, as well as how neurons diversify in general, according to the authors.

“One of the goals of this project was to address an incredibly fascinating developmental biology question, which is how individual progenitor cells decide between different neuronal fates,” Satija said. “In addition to these early markers of interneuron divergence, we found numerous additional genes that increase in expression, many dramatically, at later time points.”

The association of some of these genes with neuropsychiatric diseases promises to provide a better understanding of these disorders and the development of therapeutic strategies to treat them, a particularly important notion given the paucity of new treatments, the authors said.

Over the past 50 years, there have been no fundamentally new classes of neuropsychiatric drugs, only newer versions of old drugs, the researchers pointed out.

“Our repertoire is no better than it was in the 1970s,” Fishell said.

“Neuropsychiatric diseases likely reflect the dysfunction of very specific cell types. Our study puts forward a clear picture of what cells to look at as we work to shed light on the mechanisms that underlie these disorders,” Fishell said. “What we will find remains to be seen, but we have new, strong hypotheses that we can now test.”

As a resource for the research community, the study data and software are open-source and freely accessible online.

A gallery of the drawings of Santiago Ramón y Cajal is currently on display in New York City, and will open at the MIT Museum in Boston in May 2018.

Christian Mayer, Christoph Hafemeister and Rachel Bandler served as co-lead authors on the study.

This work was supported by the National Institutes of Health (R01 NS074972, R01 NS081297, MH071679-12, DP2-HG-009623, F30MH114462, T32GM007308, F31NS103398), the European Molecular Biology Organization, the National Science Foundation and the Simons Foundation.

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

Developmental diversification of cortical inhibitory interneurons by Christian Mayer, Christoph Hafemeister, Rachel C. Bandler, Robert Machold, Renata Batista Brito, Xavier Jaglin, Kathryn Allaway, Andrew Butler, Gord Fishell, & Rahul Satija. Nature volume 555, pages 457–462 (22 March 2018) doi:10.1038/nature25999 Published: 05 March 2018

This paper is behind a paywall.