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Interim analysis from phase 3 trial of nearly 20,000 participants suggests efficacy of two-dose regimen of the adenovirus-based vaccine is 91.6% against symptomatic COVID-19 - trial reports 16 COVID-19 cases in the vaccine group (0.1% [16/14,964) and 62 cases (1.3% [62/4,902]) in the placebo group.

No serious adverse events were deemed to be associated with vaccination, and most reported adverse events were mild, including flu-like symptoms, pain at injection site and weakness or low energy.

Sub-analysis of 2,000 adults older than 60 years suggests the vaccine is similarly effective and well tolerated in this group.

Trial is ongoing and aiming to include a total of 40,000 participants - monitoring of safety and efficacy continues.

An interim analysis of data from the phase 3 trial of the COVID-19 vaccine from Russia (Gam-COVID-Vac) suggests that a two-dose regimen of the adenovirus-based vaccine offers 91.6% efficacy against symptomatic COVID-19. The preliminary findings, published in The Lancet, are based on analysis of data from nearly 20,000 participants, three-quarters of whom received the vaccine and one quarter received a placebo.

Serious adverse events (those requiring hospital admission) were rare in both the placebo (0.4% [23/5,435]) and vaccine (0.2% [45/16,427]) groups and none were considered associated with vaccination. Four deaths were reported in the trial, none of which were considered related to the vaccine. Most reported adverse events were mild, including flu-like symptoms, pain at injection site and weakness or low energy.

The Gam-COVID-Vac is a two-part vaccine that includes two adenovirus vectors - recombinant human adenovirus type 26 (rAd26-S) and recombinant human adenovirus type 5 (rAd5-S) - which have been modified to express the SARS-CoV-2 spike protein. The adenoviruses are also weakened so that they cannot replicate in human cells and cannot cause disease. Adenoviral vector vaccines have been previously used, and their safety has been confirmed in several clinical studies.

In this trial, participants were given one dose of rAd26-S, followed by a booster dose of rAd5-S 21 days later. The authors explain that using a different adenovirus vector for the booster vaccination may help create a more powerful immune response (compared with using the same vector twice), as it minimises the risk of the immune system developing resistance to the initial vector.

"Our interim analysis of the randomised, controlled, phase 3 trial of Gam-COVID-Vac in Russia has shown high efficacy, immunogenicity, and a good tolerability profile in participants aged 18 years or older," says Dr Inna V Dolzhikova, co-lead author, Gamaleya National Research Centre for Epidemiology and Microbiology, Russia. [1]

Worldwide, 64 candidate COVID-19 vaccines are currently in clinical assessment (including 13 vaccine candidates at phase 3) and 173 vaccines are in preclinical analyses. Phase 3 candidate vaccines include a variety of vaccine platforms, such as vector vaccines, mRNA vaccines, inactivated vaccines, and adjuvanted recombinant protein nanoparticles.

"Stopping the COVID-19 pandemic requires the introduction of different vaccines based on different mechanisms of action to cover diverse global health demands. Our vaccine, along with other SARS-CoV-2 vaccines, helps to diversify the world SARS-CoV-2 vaccine pipeline," says Dr Denis Logunov, co-lead author, Gamaleya National Research Centre for Epidemiology and Microbiology, Russia. [1]

Between Sept 7 and Nov 24, 2020, a total of 21,977 adults were randomly assigned to receive the vaccine (16,501) or placebo (5,476). The trial was conducted across 25 hospitals and polyclinics in Moscow, Russia. 14,964 participants in the vaccine group and 4,902 in the placebo group received two doses of the vaccine or placebo and were included in the primary interim efficacy analysis reported today. PCR tests were done at screening and at dose 2 (21 days). A further PCR test was done if participants reported symptoms of respiratory infection. Efficacy of the vaccine was calculated on the basis of the proportion of participants with PCR-confirmed COVID-19.

From 21 days after receiving the first dose (the day of dose 2), 16 cases of symptomatic COVID-19 were confirmed in the vaccine group (0.1% [16/14,964) and 62 cases (1.3% [62/4,902]) in the placebo group - equivalent to an efficacy of 91.6%.

The vaccine induced a robust humoral response (also called antibody response) and cellular immune response (also called T-cell response) with data from 342 and 44 participants, respectively. Six of the 342 participants did not mount an immune response following vaccination, possibly due to older age or individual characteristics.

The authors note that because COVID-19 cases were detected only when participants self-reported symptoms (followed by a PCR test), the efficacy analysis only includes symptomatic cases of COVID-19, and further research is needed to understand the efficacy of the vaccine on asymptomatic COVID-19, and transmission. Furthermore, median follow up was 48 days from the first dose, so the study cannot assess the full duration of protection.

Adverse events were monitored via electronic medical records, electronic diaries and telemedicine consultations. Data on serious adverse events were analysed for 21,862 participants who received at least one dose of the vaccine (16,427) or the placebo (5,435). 70 serious adverse events were reported in 68 participants, including 45 (0.2% [45/16,427]) participants in the vaccine group, and 23 (0.4% [23/5,435]) participants in the placebo group. None of the serious adverse events were considered associated with vaccination.

During the trial, four deaths were recorded - three (

Data on serious adverse events were available for all participants at the time the interim analysis was completed - among these, verified data on general adverse events was available for 12,296 participants (9,258 in the vaccine group and 4,902 in the placebo group). Most of the reported adverse events (94% [7,485/7,966]) were mild (grade 1), and included flu-like illness, injection site reactions, headache, and asthenia (physical weakness or low energy). 451 were grade 2 (5.66%) and 30 were grade 3 (0.38%).

The trial included 2,144 participants older than 60 years, and vaccine efficacy was 91.8% in this group. The vaccine was well tolerated and safety data from 1,369 of these older adults found that the most common adverse events were flu-like symptoms and local reaction. There were three episodes of serious adverse events in the placebo group (urolithiasis, sinusitis and flu-like illness) and three in the vaccine group (renal colic, deep vein thrombosis and extremity abscess). No association was found between the adverse events and vaccination.

As part of their secondary analyses, the authors explored the efficacy of the vaccine against moderate or severe COVID-19. At 21 days after the first dose, there were no cases of moderate or severe COVID-19 in the vaccine group and 20 cases in the placebo group, equivalent to an efficacy of 100% against moderate or severe COVID-19.

Although the study was not designed to assess the efficacy of a single-dose regimen, the findings hint to the early onset of a partially protective effect 16-18 days after a single-dose immunisation. From day 15-21, efficacy against moderate or severe COVID-19 was 73.6%, but further research is required to draw any robust conclusions from these observations. The research team have recently received approval to investigate the effectiveness of a single-dose regimen of the vaccine.

Most participants in the trial were white so further research will be needed to confirm the results in a more diverse group of participants. Although the study enrolled participants with comorbidities, not all risk groups are represented. All participants were aged over 18 years, and the authors report a need for further research to investigate the vaccine in adolescents and children, as well as pregnant women. The trial is ongoing and aiming to include a total of 40,000 participants - monitoring of safety and efficacy continues.

The phase 3 trial published today follows an earlier phase 1/2 trial [2] that reported safety and immunogenicity of two different formulations (one frozen, one freeze-dried) of the two-part vaccine. In this study, the liquid form of the vaccine was used, which requires storage at -18C. Storage at 2-8°C has also been approved.

Writing in a linked Comment, Professor Ian Jones, University of Reading, and Professor Polly Roy, London School of Hygiene & Tropical Medicine, UK (who were not involved in the study), say: "The development of the Sputnik V vaccine has been criticised for unseemly haste, corner cutting, and an absence of transparency. But the outcome reported here is clear and the scientific principle of vaccination is demonstrated, which means another vaccine can now join the fight to reduce the incidence of COVID-19."

The many different sensations our bodies experience are accompanied by deeply complex exchanges of information within the brain, and the feeling of pain is no exception. So far, research has shown how pain intensity can be directly related to specific patterns of oscillation in brain activity, which are altered by the activation and deactivation of the 'interneurons' connecting different regions of the brain. However, it remains unclear how the process is affected by 'inhibitory' interneurons, which prevent chemical messages from passing between these regions. Through new research published in EPJ B, researchers led by Fernando Montani at Instituto de Física La Plata, Argentina, show that inhibitory interneurons make up 20% of the circuitry in the brain required for pain processing.

The discovery represents a significant advance in researchers' understanding of how our bodies and brains respond to pain. The underlying circuitry of the pain process involves a specific configuration of interneurons, each of which link specific pairs of regions, or 'nodes' within the brain. Crucially, a certain fraction of these neurons will be inhibitory; varying the strengths of the connections they provide. To create a biologically plausible model, Montani and colleagues would first need to consider all possible links between specific pairs of nodes, and determine their relative strengths. Within a structure as complex as the brain, however, it would be virtually impossible to do this by considering each configuration individually.

The researchers overcame this issue using 'graph theory,' which studies structures made up of sets of nodes, which influence each other's behaviours via links of variable strengths. Using a novel statistical approach, they estimated the signals produced by each region of a virtual brain in a given configuration, and how far they diverge from realistic values. From their initial estimates, Montani's team could then build up a realistic graph by strengthening and weakening the influences of certain links. Their analysis revealed that a configuration where 20% of all interneurons associated with the pain process are inhibitory to information transmission.

A soft, flexible sensor system created with electrically conductive yarns could help map problematic pressure points in the socket of an amputee's prosthetic limb, researchers from North Carolina State University report in a new study.

In IEEE Sensors Journal, researchers from North Carolina State University reported on the lightweight, soft textile-based sensor prototype patch. The device incorporates a lattice of conductive yarns and is connected to a tiny computer. They tested the system on a prosthetic limb and in walking experiments with two human volunteers, finding the system could reliably track pressure changes in real time.

"What people commonly use to measure pressure within prosthetics are rigid sensors," said the study's first author Jordan Tabor, a graduate student in the NC State College of Textiles. "They're hard, they're bulky; they can be heavy. These are not things that amputees can use on a daily basis because rigid sensors negatively affect the fit of amputees' prosthetics. Rigid sensors can also cause discomfort. We designed sensors that can be integrated into textiles in a way that doesn't cause any additional discomfort for the user, and could be worn on a more regular basis."

In one experiment, the researchers tested whether the patch could detect changes in pressure when they placed it on an artificial limb, turned at different angles. Then they used it to test pressure changes when an able-bodied person wore the sensor patch while walking with a bent-knee adaptor and while shifting their weight between legs.

In their last experiment, a volunteer with an amputated lower leg wore the patch on the liner of their prosthetic limb in areas where the prosthetic typically applies higher pressure. They tested the sensor patch while the volunteer shifted weight and walked on a treadmill, finding the system was durable and could reliably monitor pressure changes in the socket.

"This approach that we thought of a few years ago does work, and it's a readily manufacturable technology," said Tushar Ghosh, the study's co-corresponding author. "You cannot put materials next to the skin that are uncomfortable and may not be safe. So we are putting things that are used around us all the time, and are soft and flexible." Ghosh is the William A. Klopman Distinguished Professor of Textile Engineering, Chemistry & Science in NC State's Wilson College of Textiles.

Part of the researchers' work involved designing the sensor system to be lightweight and small enough for human use. The work was a collaboration between researchers in textile, electrical, computer and biomedical engineering at NC State. The human experiments were performed by rehabilitation engineering researchers led by Helen Huang, the Jackson Family Distinguished Professor in the UNC/NC State Joint Department of Biomedical Engineering and a senior co-author of the paper.

They created the sensor patch by sewing the yarns together in such a way that they created an electromagnetic field. When the researchers sewed the yarns into a lattice, and applied a small amount of electrical power using a small battery, they found they could measure the amount of electrical charge drawing the yarns together at each lattice point. The charges change depending on how close the yarns are together, which is related to how much pressure is applied by the wearer. They connected yarns, insulated them, laid them on a textile fabric, and connected them to a small electronic device to capture the data. They also included a small radio in order to wirelessly track the measurements.

"We connected the textile fibers to an electrical circuit that is a little larger than a quarter, and that can scan as many as 10 by 10 fibers," said the study's co-corresponding author Alper Bozkurt, professor of electrical engineering at NC State. "That gives us 100 points of measurement. Everything is connected to a tiny microcomputer, which has a radio for wireless data tracking."

While researchers used a yarn that was commercially available for the study, they are also working on developing their own textile fiber to detect more than just pressure changes in the socket of an amputee's prosthetic limb.

The next step in the project is to integrate the sensors into prosthetic sockets directly, or into a wearable item. They would also need to study the sensor's potential clinical value in a larger study.

"Our broader vision is to design something like a sock, or to integrate the sensor system into the prosthetic socket, so when a person dons their prosthesis, they are able to monitor what's happening in terms of pressure distribution and other measurements," Huang said.

WASHINGTON, February 2, 2021 -- Scientists are hoping advances in cancer research could lead to a day when a patient's own immune system could be used to fight and destroy a wide range of tumors.

Cancer immunotherapy has some remarkable successes, but its effectiveness has been limited to a relatively small handful of cancers. In APL Bioengineering, by AIP Publishing, a team from Stanford University and Genentech describes how advances in engineering models of tumors can greatly expand cancer immunotherapy's effectiveness to a wider range of cancers.

"One of the biggest breakthroughs we've had in cancer research in decades is that we can modify the cells in your own immune system to make them kill cancer cells," said author Joanna Lee.

Using existing immunotherapy advances, scientists have figured out a way to make the T-cells already inside "hot" or inflamed tumors start fighting them. But that breakthrough does not help with "cold" or noninflamed tumors, because the immune cells are not in the right place.

"Now, a big push in drug discovery in cancer is how do how to make those cold tumors hot?" Lee said. "How do we get immune cells into those tumors?"

To do that, scientists need to first recreate those changes in a laboratory. While much research can be done in a 2D environment, like a petri dish, modeling the way immune cells interact with cancer requires a more advanced 3D environment.

Building the tumor microenvironment, Lee said, will require expertise from both biologists, like herself, and engineers, like co-author Ovijit Chaudhuri.

"Trying to merge those two fields together is what has made the 3D culture field really challenging," she said. "The reason it's so hard is we are not just talking about having a plate you throw some cells in. It is more like building a house."

A faithful 3D model for cold tumors would make the research leading to new cancer drugs faster and more efficient. Lee said that is a big deal in a field where proposed new treatments take years to be approved and an overwhelming 96.6 % of them fail.

"If we could translate the success we've had with inflamed tumors to cold tumors, that would be a huge breakthrough," Lee said. "That's what we are going for in building these 3D culture models."

Researchers at the George Washington University and University of California, Los Angeles, have developed and demonstrated for the first time a photonic digital to analog converter without leaving the optical domain. Such novel converters can advance next-generation data processing hardware with high relevance for data centers, 6G networks, artificial intelligence and more.

Current optical networks, through which most of the world's data is transmitted, as well as many sensors, require a digital-to-analog conversion, which links digital systems synergistically to analog components.

Using a silicon photonic chip platform, Volker J. Sorger, an associate professor of electrical and computer engineering at GW, and his colleagues have created a digital-to-analog converter that does not require the signal to be converted in the electrical domain, thus showing the potential to satisfy the demand for high data-processing capabilities while acting on optical data, interfacing to digital systems, and performing in a compact footprint, with both short signal delay and low power consumption.

"We found a way to seamlessly bridge the gap that exists between these two worlds, analog and digital," Sorger said. "This device is a key stepping stone for next-generation data processing hardware."

Read the study, "Electronic Bottleneck Suppression in Next-Generation Networks with Integrated Photonic Digital-to-Analog Converters," here.

DeKalb, Ill. -- If you build it, they might not come. That's the key finding of a new study on habitat restoration practices that challenges a commonly accepted principle in ecology.

The study tested the "Field of Dreams" hypothesis, which predicts that restoring plant biodiversity will lead to recovery of animal biodiversity. The prediction, which often guides restoration practices, is infrequently tested because restoration studies typically measure plant or animal biodiversity, but rarely both, said lead author Pete Guiden, a post-doctoral researcher at Northern Illinois University.

Guiden and NIU colleagues studied 17 research plots of restored tallgrass prairie, measuring biodiversity in four animal communities--snakes, small mammals and ground and dung beetles. "We wanted to know if the most diverse animal communities were found in the most diverse plant communities, or if something else is responsible for patterns of animal biodiversity," he said.

While the scientists did find some positive connections between plant and animal biodiversity, the gains weren't nearly as strong as benefits derived from implementation of restoration management strategies.

"We found that the effects of management strategies like controlled burns and bison reintroduction on animal communities were six times stronger on average than the effects of plant biodiversity," Guiden said.

"The most important effects of restoration on animal biodiversity had little to do with plant community biodiversity," he added. "So management practices focused on restoring plants might be insufficient to also restore animals."

The study is published in the Proceedings of the National Academy of Sciences.

Co-authors include NIU professors Holly Jones (biology, environmental studies) and Richard King (biology); NIU post-doctoral fellow John Vanek; NIU graduate student Erin Rowland; former NIU students Ryan Blackburn, Anna Farrell, Jessica Fliginger, Sheryl C. Hosler, Melissa Nelson and Kirstie Savage; and former NIU professor Nicholas Barber of San Diego State University.

This is an important study," said Jones, whose Evidence-based Restoration Laboratory at NIU carried out the research. "With Earth's biodiversity rapidly disappearing, ecological restoration has emerged as an important strategy to slow or reverse biodiversity losses. Critical tests of the Field of Dreams and other hypotheses are needed to improve restoration science and ensure we get the most bang for our buck."

The study results were a surprise to the authors, who had predicted that plant biodiversity would have stronger effects on animal biodiversity than management strategies.

"We expected plant biodiversity to be important because having more plant species allows animals to split up food resources or habitat," Guiden said. "However, the strong effects of land management on animal biodiversity highlight the important role of people in shaping the quantity or quality of habitat, especially through disturbance regimes used in restoration."

The scientists' work was conducted at Nachusa Grasslands, a 3,800-acre nature preserve in Franklin Grove, Illinois, managed by The Nature Conservancy. Since 1986, Nachusa crew members and volunteers have been reconnecting remnant prairie, woodlands and wetlands through habitat restoration to create one of the largest and most biologically diverse grasslands in Illinois. Tallgrass prairie is one of the most globally imperiled ecosystems.

"While Illinois is known as the Prairie State, 99.9 percent of its prairie has been lost to agriculture and development," Jones said. "Nachusa Grasslands is an incredible success story. What The Nature Conservancy has done is show us we can restore ecosystems. What was once rows of corn is now a really high-functioning prairie that also serves as a living laboratory for restoration scientists."

The 17 research sites studied measured 60-by-60 meters and had restoration ages spanning three to 32 years. Each site experienced a unique controlled-burn history, and bison had been reintroduced to eight of the sites between 2014 and 2015. For Nachusa Grasslands, fire and bison-grazing are key management practices that are components of healthy prairies and together can increase plant and animal biodiversity.

By simultaneously measuring plant and animal responses to restoration disturbances, the scientists were able to tease out and compare management-driven and plant-driven effects.

Guiden said each animal community studied differed considerably in its specific responses to restoration. In fact, the study found that restoration can simultaneously have positive and negative effects on biodiversity through different pathways, which may help reconcile why there can be variation in restoration outcomes.

For example, in older restorations, high diversity among plants resulted in a decrease in a specific diversity measure for dung beetles, likely because key resources became more difficult to find. On the other hand, older restorations also had soil conditions that provided high quality habitat for a wide range of other species.

Guiden also noted that the animals studied in this research project are decomposers (dung beetles), omnivores (small mammals) or carnivores (snakes, ground beetles). "Animal communities composed of herbivores, particularly species highly specialized on specific prairie plants, may show stronger relationships to plant diversity," he said.

Ecosystems are difficult to restore because they represent such highly intricate webs of species' interactions with each other and their environments, Jones said.

"Our study shows that it's critical to define restoration goals before projects get off the ground and to measure progress," she said. "This will help ensure the restoration is eliciting the desired responses.

"Perhaps more importantly, our study shows these active restoration techniques of introducing megaherbivores like bison, which were near extinction last century, and fire regimes that Indigenous people used to set to prairies, are absolutely critical components to recreating those complex webs of species and interactions. Seeding alone gets us started, but extra management super charges the animal communities that are critical to maintaining healthy prairies."

The mesmerizing flow of a sidewinder moving obliquely across desert sands has captivated biologists for centuries and has been variously studied over the years, but questions remained about how the snakes produce their unique motion. Sidewinders are pit vipers, specifically rattlesnakes, native to the deserts of the southwestern United State and adjacent Mexico.

Scientists had already described the microstructure of the skin on the ventral, or belly, surface of snakes. Many of the snakes studied, including all viper species, had distinctive rearward facing "microspicules" (micron-sized protrusions on scales) that had been interpreted in the context of reducing friction in the forward direction--the direction the crawling snake--and increasing friction in the backward direction to reduce slip.

Considered through the lens of a sidewinder's peculiar form of locomotion, however, it seemed that these microspicules would not function in the same manner. But no one had examined the microstructure of sidewinders, nor of a handful of unrelated African vipers that also sidewind.

Working with naturally-shed skins collected from snakes in zoos, researchers used atomic force microscopy to visualize and measure the microstructures of these scale protrusions in three species of sidewinding vipers as well as many other viper species for comparison. The results of the research, published this week in the journal Proceedings of the National Academy of Sciences, found that indeed the sidewinders have a unique structure distinct from other snakes.

The microspicules were absent in the African sidewinding species and reduced to tiny nubbins in the North American sidewinder. All three snakes also had distinctive crater-like micro-depressions producing a distinctive texture not seen in other snakes.

Daniel Goldman, Dunn Family Professor of Physics at the Georgia Institute of Technology, and Jennifer Rieser, working as a postdoctoral researcher in Goldman's group and currently an assistant professor in the Department of Physics at Emory University, developed mathematical models to test how both the typical texture of rearward-directed microspicules and spicule-less cratered texture function as snakes interact with the ground. The models revealed that the microspicules would actually impede sidewinding, explaining their evolutionary loss in these species.

The models also revealed an unexpected result that microspicules function to improve performance of snakes that use lateral undulation to move. Lateral undulation is the typical side-to-side mode locomotion used by the majority of snake species. "This discovery adds a new dimension to our knowledge of the functionality of these structures, that is more complex than the previous ideas," said Joseph Mendelson, director of research at Zoo Atlanta and adjunct associate professor in the Georgia Tech School of Biological Sciences.

The models indicate that the microspicules act a bit like corduroy fabric. "Friction is low when you run your finger along the length of the furrowed fabric--consistent with previous work--but the furrows produce significant friction when you move your finger sideways across the fabric texture," said Goldman. The functionality of the distinct craters remains a mystery.

The findings could be important to the development of future generations of robots able to move across challenging surfaces such as loose sand. "Understanding how and why this example of convergent evolution works may allow us to adapt it for our own needs, such as building robots that can move in challenging environments," Rieser said.

In terms of anatomy, this was a classic example of convergent evolution between a pair of snake species in Africa and a very distantly related snake in North America, Mendelson noted. Biogeographic reconstructions conducted by Jessica Tingle, a doctoral student at University of California Riverside, indicated that the African snakes are evolutionarily much older than the North American sidewinder, suggesting that the sidewinders represented an earlier phase in adaptation for sidewinding.

Tai-De Li, then at Georgia Tech in the lab of Prof Elisa Riedo and now at the City University of New York, did the AFM measurements.

Drawing from the fields of evolutionary biology, living systems physics, and mathematical modelling, the team produced a study that explains some aspects of what these microstructures on the bellies of snakes do and how they evolved in snakes.

"Our results highlight how an integrated approach can provide quantitative predictions for structure-function relationships and insights into behavioral and evolutionary adaptions in biological systems," the authors wrote.

A fascinating and crucial ability of biological tissue, such as muscle, is self-healing and self-strengthening in response to damage caused by external forces. Most human-made polymers, on the other hand, break irreversibly under enough mechanical stress, which makes them less useful for certain critical applications like manufacturing artificial organs. But what if we could design polymers that reacted chemically to mechanical stimuli and used this energy to enhance their properties?

This goal, which has proven to be a big challenge, is under the spotlight in the field of mechanochemistry. In a recent study published in Angewandte Chemie International Edition, a team of scientists from Tokyo Tech, Yamagata University, and Sagami Chemical Research Institute, Japan, made remarkable progress with bulk self-strengthening polymers. Professor Hideyuki Otsuka, who led the study, explains their motivation: "Furthering the development of elegant bulk systems in which a force-induced reaction causes a clear change in mechanical properties would represent a game-changing advance in mechanochemistry, polymer chemistry, and materials science." They achieved this goal by focusing on difluorenylsuccinonitrile (DFSN), a 'mechanophore' or molecule that responds to mechanical stress.

The team created segmented polyurethane polymeric chains with hard as well as soft functional segments. The soft segments contain DFSN molecules acting as their "weakest link," with both of its halves joined by a single covalent bond. The soft segments also have their side chains topped off with methacryloyl units. Upon applying mechanical stress, such as simple compression or extension, on the polymer, the DFSN molecule splits into two equal cyanofluorene (CF) radicals. These CF radicals, unlike DFSN, acquire a pink color, making it easy to visually detect mechanical damage.

Most importantly, the CF radicals react with the methacryloyl units in the side chains of other polymers, causing separate polymers to chemically hook to one another in a process known as cross-linking. This phenomenon ultimately makes the overall strength of the bulk material go up as polymers become more chemically intertwined. This chemical cross-linking effect, as the scientists proved experimentally, becomes more pronounced as more compression cycles are performed on the segmented polymer samples because more DFSN molecules are split into CF radicals.

In addition, the team created a slight variant of their segmented polymer that not only turns pink but also exhibits fluorescence under ultraviolet irradiation when mechanical force is applied to it. This functionality comes in handy when trying to more accurately quantify the extent of the damage done by mechanical stress.

The attractive properties and functionalities of the developed polymers are useful, for example, for intuitive damage detection and the creation of adaptive materials. Expressing excitement for their findings, Otsuka remarks: "We successfully developed unprecedented mechanoresponsive polymers that exhibit color change, fluorescence, and self-strengthening ability, marking the first report of force-induced cross-linking reactions achieved by simply the extension or compression of a bulk film. Our findings represent a significant advance in the fundamental research of mechanochemistry and its applications in material science."

As more mechano-responsive materials with unique functions are developed, we can expect to explore their myriad applications in various industrial and engineering fields. Be sure to keep an eye out for further progress in mechanochemistry!

Tumors can be damaging to surrounding blood vessels and tissues even if they're benign. If they're malignant, they're aggressive and sneaky, and often irrevocably damaging. In the latter case, early detection is key to treatment and recovery. But such detection can sometimes require advanced imaging technology, beyond what is available commercially today.

For instance, some tumors occur deep inside organs and tissues, covered by a mucosal layer, which makes it difficult for scientists to directly observe them with standard methods like endoscopy (which inserts a small camera into a patient's body via a thin tube) or reach them during biopsies. In particular, gastrointestinal stromal tumors (GISTs)--typically found in the stomach and the small intestines--require demanding techniques that are very time-consuming and prolong the diagnosis. Now, to improve GIST diagnosis, Drs. Daiki Sato, Hiroaki Ikematsu, and Takeshi Kuwata from the National Cancer Center Hospital East in Japan, Dr. Hideo Yokota from the RIKEN Center for Advanced Photonics, Japan, and Drs. Toshihiro Takamatsu and Kohei Soga from Tokyo University of Science, Japan, led by Dr. Hiroshi Takemura, have developed a technology that uses near-infrared hyperspectral imaging (NIR-HSI) along with machine learning. Their findings are published in Nature's Scientific Reports.

"This technique is a bit like X-rays, the idea is that you use electromagnetic radiation that can pass through the body to generate images of structures inside," Dr. Takemura explains, "The difference is that X-rays are at 0.01-10 nm, but near-infrared is at around 800-2500 nm. At that wavelength, near-infrared radiation makes tissues seem transparent in images. And these wavelengths are less harmful to the patient than even visible rays."

This should mean that scientists can safely investigate something that is hidden inside tissues, but until the study by Dr. Takemura and his colleagues, no one had attempted to use NIR-HSI on deep tumors like GISTs. Speaking of what got them to go down this line of investigation, Dr. Takemura pays homage to the late professor who began their journey: "This project has been possible only because of late Prof. Kazuhiro Kaneko, who broke the barriers between doctors and engineers and established this collaboration. We are following his wishes."

Dr. Takemura's team performed imaging experiments on 12 patients with confirmed cases of GISTs, who had their tumors removed through surgery. The scientists imaged the excised tissues using NIR-HSI, and then had a pathologist examine the images to determine the border between normal and tumor tissue. These images were then used as training data for a machine-learning algorithm, essentially teaching a computer program to distinguish between the pixels in the images that represent normal tissue versus those that represent tumor tissue.

The scientists found that even though 10 out of the 12 test tumors were completely or partly covered by a mucosal layer, the machine-learning analysis was effective in identifying GISTs, correctly color-coding tumor and non-tumor sections at 86% accuracy. "This is a very exciting development," Dr. Takemura explains, "Being able to accurately, quickly, and non-invasively diagnose different types of submucosal tumors without biopsies, a procedure that requires surgery, is much easier on both the patient and the physicians."

Dr. Takemura acknowledges that there are still challenges ahead, but feels they are prepared to solve them. The researchers identified several areas that would improve on their results, such as making their training dataset much larger, adding information about how deep the tumor is for the machine-learning algorithm, and including other types of tumors in the analysis. Work is also underway to develop an NIR-HSI system that builds on top of existing endoscopy technology.

"We've already built a device that attaches an NIR-HSI camera to the end of an endoscope and hope to perform NIR-HSI analysis directly on a patient soon, instead of just on tissues that had been surgically removed," Dr. Takemura says, "In the future, this will help us separate GISTs from other types of submucosal tumors that could be even more malignant and dangerous. This study is the first step towards much more groundbreaking research in the future, enabled by this interdisciplinary collaboration."

For now, a means of accurately and non-invasively detecting GISTs early on could be clinically available widely, soon!

Topological insulators are one of the most puzzling quantum materials - a class of materials whose electrons cooperate in surprising ways to produce unexpected properties. The edges of a TI are electron superhighways where electrons flow with no loss, ignoring any impurities or other obstacles in their path, while the bulk of the material blocks electron flow.

Scientists have studied these puzzling materials since their discovery just over a decade ago with an eye to harnessing them for things like quantum computing and information processing.

Now researchers at the Department of Energy's SLAC National Accelerator Laboratory and Stanford University have invented a new, hands-off way to probe the fastest and most ephemeral phenomena within a TI and clearly distinguish what its electrons are doing on the superhighway edges from what they're doing everywhere else.

The technique takes advantage of a phenomenon called high harmonic generation, or HHG, which shifts laser light to higher energies and higher frequencies - much like pressing a guitar string produces a higher note - by shining it through a material. ­­By varying the polarization of laser light going into a TI and analyzing the shifted light coming out, researchers got strong and separate signals that told them what was happening in each of the material's two contrasting domains.

"What we found out is that the light coming out gives us information about the properties of the superhighway surfaces," said Shambhu Ghimire, a principal investigator with the Stanford PULSE Institute at SLAC, where the work was carried out. "This signal is quite remarkable, and its dependence on the polarization of the laser light is dramatically different from what we see in conventional materials. We think we have a potentially novel approach for initiating and probing quantum behaviors that are supposed to be present in a broad range of quantum materials."

The research team reported the results in Physical Review A today.

Light in, light out

Starting in 2010, a series of experiments led by Ghimire and PULSE Director David Reis showed HHG can be produced in ways that were previously thought unlikely or even impossible: by beaming laser light into a crystal, a frozen argon gas or an atomically thin semiconductor material. Another study described how to use HHG to generate attosecond laser pulses, which can be used to observe and control the movements of electrons, by shining a laser through ordinary glass.

In 2018, Denitsa Baykusheva, a Swiss National Science Foundation Fellow with a background in HHG research, joined the PULSE group as a postdoctoral researcher. Her goal was to study the potential for generating HHG in topological insulators - the first such study in a quantum material. "We wanted to see what happens to the intense laser pulse used to generate HHG," she said. "No one had actually focused such a strong laser light on these materials before."

But midway through those experiments, the COVID-19 pandemic hit and the lab shut down in March 2020 for all but essential research. So the team had to think of other ways to make progress, Baykusheva said.

"In a new area of research like this one, theory and experiment have to go hand in hand," she explained. "Theory is essential for explaining experimental results and also predicting the most promising avenues for future experiments. So we all turned ourselves into theorists" - first working with pen and paper and then writing code and doing calculations to feed into computer models.

An illuminating result

To their surprise, the results predicted that circularly polarized laser light, whose waves spiral around the beam like a corkscrew, could be used to trigger HHG in topological insulators.

"One of the interesting things we observed is that circularly polarized laser light is very efficient at generating harmonics from the superhighway surfaces of the topological insulator, but not from the rest of it," Baykusheva said. "This is something very unique and specific to this type of material. It can be used to get information about electrons that travel the superhighways and those that don't, and it can also be used to explore other types of materials that can't be probed with linearly polarized light."

The results lay out a recipe for continuing to explore HHG in quantum materials, said Reis, who is a co-author of the study.

"It's remarkable that a technique that generates strong and potentially disruptive fields, which takes electrons in the material and jostles them around and uses them to probe the properties of the material itself, can give you such a clear and robust signal about the material's topological states," he said.

"The fact that we can see anything at all is amazing, not to mention the fact that we could potentially use that same light to change the material's topological properties."

Experiments at SLAC have resumed on a limited basis, Reis added, and the results of the theoretical work have given the team new confidence that they know exactly what they are looking for.

Many surgeries today are performed via minimally invasive procedures, in which a small incision is made and miniature cameras and surgical tools are threaded through the body to remove tumors and repair damaged tissues and organs. The process results in less pain and shorter recovery times compared to open surgery.

While many procedures can be performed in this way, surgeons can face challenges at an important step in the process: the sealing of internal wounds and tears.

Taking inspiration from origami, MIT engineers have now designed a medical patch that can be folded around minimally invasive surgical tools and delivered through airways, intestines, and other narrow spaces, to patch up internal injuries. The patch resembles a foldable, paper-like film when dry. Once it makes contact with wet tissues or organs, it transforms into a stretchy gel, similar to a contact lens, and can stick to an injured site.

In contrast to existing surgical adhesives, the team's new tape is designed to resist contamination when exposed to bacteria and bodily fluids. Over time, the patch can safely biodegrade away. The team has published its results in the journal Advanced Materials.

The researchers are working with clinicians and surgeons to optimize the design for surgical use, and they envision that the new bioadhesive could be delivered via minimally invasive surgical tools, operated by a surgeon either directly or remotely via a medical robot.

"Minimally invasive surgery and robotic surgery are being increasingly adopted, as they decrease trauma and hasten recovery related to open surgery. However, the sealing of internal wounds is challenging in these surgeries," says Xuanhe Zhao, professor of mechanical engineering and of civil and environmental engineering at MIT.

"This patch technology spans many fields," adds co-author Christoph Nabzdyk, a cardiac anesthesiologist and critical care physician at the Mayo Clinic in Rochester, Minnesota. "This could be used to repair a perforation from a coloscopy, or seal solid organs or blood vessels after a trauma or elective surgical intervention. Instead of having to carry out a full open surgical approach, one could go from the inside to deliver a patch to seal a wound at least temporarily and maybe even long-term."

The study's co-authors include lead authors Sarah Wu and Hyunwoo Yuk, and Jingjing Wu at MIT.

Layered protection

The bioadhesives currently used in minimally invasive surgeries are available mostly as biodegradable liquids and glues that can be spread over damaged tissues. When these glues solidify, however, they can stiffen over the softer underlying surface, creating an imperfect seal. Blood and other biological fluids can also contaminate glues, preventing successful adhesion to the injured site. Glues can also wash away before an injury has fully healed, and, after application, they can also cause inflammation and scar tissue formation.

Given the limitations of current designs, the team aimed to engineer an alternative that would meet three functional requirements. It should be able to stick to the wet surface of an injured site, avoid binding to anything before reaching its destination, and once applied to an injured site resist bacterial contamination and excessive inflammation.

The team's design meets all three requirements, in the form of a three-layered patch. The middle layer is the main bioadhesive, made from a hydrogel material that is embedded with compounds called NHS esters. When in contact with a wet surface, the adhesive absorbs any surrounding water and becomes pliable and stretchy, molding to a tissue's contours. Simultaneously, the esters in the adhesive form strong covalent bonds with compounds on the tissue surface, creating a tight seal between the two materials. The design of this middle layer is based on previous work in Zhao's group.

The team then sandwiched the adhesive with two layers, each with a different protective effect. The bottom layer is made from a material coated with silicone oil, which acts to temporarily lubricate the adhesive, preventing it from sticking to other surfaces as it travels through the body. When the adhesive reaches its destination and is pressed lightly against an injured tissue, the silicone oil is squeezed out, allowing the adhesive to bind to the tissue.

The adhesive's top layer consists of an elastomer film embedded with zwitterionic polymers, or molecular chains made from both positive and negative ions that act to attract any surrounding water molecules to the elastomer's surface. In this way, the adhesive's outward-facing layer forms a water-based skin, or barrier against bacteria and other contaminants.

"In minimally invasive surgery, you don't have the luxury of easily accessing a site to apply an adhesive," Yuk says. "You really are battling a lot of random contaminants and body fluids on your way to your destination."

Fit for robots

In a series of demonstrations, the researchers showed that the new bioadhesive strongly adheres to animal tissue samples, even after being submerged in beakers of fluid, including blood, for long periods of time.

They also used origami-inspired techniques to fold the adhesive around instruments commonly used in minimally invasive surgeries, such as a balloon catheter and a surgical stapler. They threaded these tools through animal models of major airways and vessels, including the trachea, esophagus, aorta, and intestines. By inflating the balloon catheter or applying light pressure to the stapler, they were able to stick the patch onto torn tissues and organs, and found no signs of contamination on or near the patched-up site up to one month after its application.

The researchers envision that the new bioadhesive could be manufactured in prefolded configurations that surgeons can easily fit around minimally invasive instruments as well as on tools that are currently being used in robotic surgery. They are seeking to collaborate with designers to integrate the bioadhesive into robotic surgery platforms.

"We believe that the conceptual novelty in the form and function of this patch represents an exciting step toward overcoming translational barriers in robotic surgery and facilitating the wider clinical adoption of bioadhesive materials," Wu says.

CHARLOTTESVILLE, VA (FEBRUARY 2, 2021). Researchers in the United Kingdom (UK) conducted a randomized controlled trial in 47 patients with lumbar spinal stenosis to compare treatment outcomes and costs of two competing surgical procedures: insertion of the X-Stop® (Medtronic) interspinous distractor device and open decompression surgery with laminectomy. Both procedures improved the patients' quality of life; however, overall, laminectomy gave patients a better quality of life and was also more cost-effective.

Detailed findings of this study can be found in a new article, "A randomized controlled trial of the X-Stop interspinous distractor device versus laminectomy for lumbar spinal stenosis with 2-year quality-of-life and cost-effectiveness outcomes," published today in the Journal of Neurosurgery: Spine.

Background: Lumbar spinal stenosis is the term used to describe narrowing of the spinal canal within the lower lumbar spine. This narrowing, often a sign of aging, may be due to bone spurs resulting from arthritis, a bulging spinal disc, or thickened ligaments. As the spinal canal narrows, spinal nerves passing through it can become compressed and inflamed, leading to weakness, numbness, and/or pain in the lower back and legs, and, occasionally, bladder or bowel dysfunction.

In many cases, lumbar spinal stenosis can be managed nonsurgically by use of medicines to reduce swelling and pain, physical therapy, and specific exercises. However, in some cases, these are ineffective and spinal surgery is recommended. Most often, laminectomy is performed by removing a portion of bone on the back of the lumbar vertebra at the site of compression, allowing the spinal canal to expand and relieving pressure on the spinal nerves.

Traditional laminectomy is open surgery usually requiring general anesthesia and a few days in the hospital. X-Stop® surgery is less invasive. Often placed after administration of a local anesthetic agent, the X-Stop® Interspinous Process Decompression System (Medtronic), composed of a titanium alloy, is inserted at the back of lumbar vertebrae, between the spinous processes of adjacent vertebrae at the site of spinal canal narrowing. Once there, the device prevents the spine from bending too far backward, compressing spinal nerves and causing discomfort.

Present Study: In this article, the authors describe a prospective, open-label, randomized controlled trial, "Cost-Effectiveness and Quality of Life After Laminectomy or X-Stop (CELAX)," in which open laminectomy and use of the X-Stop® device for the treatment of lumbar spinal stenosis were compared. The primary outcomes investigated were cost-effectiveness and long-term quality of life. The study was conducted at three medical centers in the UK.

Between 2010 and 2014, 47 patients who experienced neurogenic caudication from lumbar spinal stenosis and whose symptoms improved on forward flexion were randomized into one of two treatment groups: 26 patients underwent laminectomy and 21 patients received the X-Stop® device. The surgical procedures were performed by consulting and attending surgeons as well as by residents. General anesthesia was used in all cases.

Eighteen women and 29 men, ranging in age from 47 to 86 years, participated fully in the clinical trial. During the course of the study, five patients in the X-Stop® group crossed over into the laminectomy group.

Quality of life for the patients was measured using EQ-5D instruments (EuroQuol Group) before the procedure and again at 6 months, 1 year, and 2 years post-procedure. Costs per patient were based on the cost of time in the operating room plus the cost of the hospital stay.

Six months after treatment, the mean quality of life in both the laminectomy and X-Stop® groups was significantly better than that measured at baseline (pretreatment). At 1 and 2 years post-treatment, the improved quality of life demonstrated in the laminectomy group continued to be significantly better than baseline; in the X-Stop® group, quality of life remained improved but not significantly so.

In this clinical study, the mean cost for a laminectomy was £2712 ($3316) and that for the X-Stop® procedure was £5148 ($6295). Surgery took nearly twice as long when laminectomy was performed (mean 122 minutes compared with 66 minutes for X-Stop® insertion). The mean length of hospital stay was comparable: 4.3 days in the laminectomy group and 4.2 days in the X-Stop® group. The increase in the cost of the X-Stop® procedure was due in large part to the cost of the device.

There were four complications in the laminectomy group, although only one required a return to the operating room. There were two complications in the X-Stop® group, both of which necessitated removal of the device and a switch to laminectomy. Treatment with the X-Stop® device was later found to be inadequate in three patients, who then also underwent surgery for laminectomy and removal of the device.

Additional data on primary and secondary outcomes are provided in the article and in a supplemental file online.

The authors conclude that laminectomy is more cost-effective than the X-Stop® device for the treatment of lumbar spinal stenosis. The X-Stop® device improved quality of life but less so than laminectomy. Nevertheless, the interspinous distractor device still provides a service. The authors suggest that the X-Stop® "should be reserved for cases in which a less-invasive procedure is required. There is no justification for its regular use as an alternative to decompressive surgery."

When asked about the findings of this study, Dr. Anouk Borg, first author of the paper, responded, "It is very encouraging that both treatments resulted in an improvement in the quality of life for our patients. The X-Stop® device is an attractive option as it is less invasive than standard open surgery. It is also a faster procedure and it is reversible. The device can be removed if required. However, we found that open laminectomy is a more cost-effective procedure in the UK, with sustained improvement in quality of life up to the trial endpoint at 2 years."

A new method for constructing special solar cells could significantly increase their efficiency. Not only are the cells made up of thin layers, they also consist of specifically arranged nanoblocks. This has been shown in a new study by an international research team led by the Martin Luther University Halle-Wittenberg (MLU), which was published in the scientific journal Nano Letters.

Commercially available solar cells are mostly made of silicon. "Based on the properties of silicon it's not feasible to say that their efficiency can be increased indefinitely," says Dr Akash Bhatnagar, a physicist from the Centre for Innovation Competence (ZIK) "SiLi-nano" at MLU. His research team is therefore studying the so-called anomalous photovoltaic effect which occurs in certain materials. The anomalous photovoltaic effect does not require a p-n junction which otherwise enables the flow of current in silicon solar cells. The direction of the current is determined at the atomic level by the asymmetric crystal structure of the corresponding materials. These materials are usually oxides, which have some crucial advantages: they are easier to manufacture and significantly more durable. However, they often do not absorb much sunlight and have a very high electrical resistance. "In order to utilise these materials and their effect, creative cell architectures are needed that reinforce the advantages and compensate for the disadvantages," explains Lutz Mühlenbein, lead author of the study.

In their new study, the physicists introduced a novel cell architecture, a so-called nanocomposite. They were supported by teams from the Bergakademie Freiberg, the Leibniz Institute of Surface Modification in Leipzig and Banaras Hindu University in India. In their experiment, the researchers stacked single layers of a typical material only a few nanometres in thickness on top of one another and offset them with nickel oxide strips running perpendicularly. "The strips act as a fast lane for the electrons that are generated when sunlight is converted into electricity and which are meant to reach the electrode in the solar cell," Bhatnagar explains. This is precisely the transport that would otherwise be impeded by the electrons having to traverse each individual horizontal layer.

The new architecture actually increased the cell's electrical output by a factor of five. Another advantage of the new method is that it is very easy to implement. "The material forms this desired structure on its own. No extreme external conditions are needed to force it into this state," says Mühlenbein. The idea, for which the researchers have now provided an initial feasibility study, could also be applied to materials other than nickel oxide. Follow-up studies now need to examine if and how such solar cells can be produced on an industrial scale.

Toronto, ON - Results of a multi-centre, international, clinical trial co-led by Peter Munk Cardiac Centre (PMCC) cardiologist Dr. Dinesh Thavendiranathan point to the benefit of using a more sensitive test to detect heart function issues early, so cancer patients don't have to fight heart failure too.

Unfortunately, for 1 in 20 high-risk patients, treating cancer with certain therapies means the added potential of developing heart failure. The one-year results of the highly anticipated trial compared heart function at the end of anthracycline-based chemotherapy, a treatment that can successfully treat cancer but also damage the heart, known as cardiotoxicity.

"When I was diagnosed, I was scared for my life," says Sindhu Johnson, a breast cancer patient and one of 307 participants, 90% of which had breast cancer, enrolled in the trial.

"I was willing to undertake any treatment, but I understood my survival may come at a price. And that price included cardiotoxicity."

Dr. Thavendiranathan is the lead of the Cardiotoxicity Prevention Program at the Ted Rogers Centre for Heart Research at the PMCC and a recognized leader in cardiotoxicity.

"We hoped our study would show a better way to care for cancer patients, who are already fighting one disease and should not have to worry about the future risk of heart failure too," says Dr. Thavendiranathan.

Trial participants were split into two groups and monitored during their cancer treatment. One group received the current standard of care, measuring Left Ventricular Ejection Fraction (LVEF) with traditional imaging technology known as echocardiography. The other group received the current standard of care as well as an additional imaging method, measuring Global Longitudinal Strain (GLS).

LVEF measures how much blood is pumped out of the left ventricle of the heart with each contraction, whereas GLS measures deformation of the heart muscle.

"LVEF is the traditional imaging method, but we already know measuring GLS allows for a better identification of heart damage," says Dr. Thavendiranathan. "What we didn't know is if we can reduce the risk of cardiotoxicity by intervening once this early heart damage is detected."

Published in the Journal of the American College of Cardiology, the "Strain Surveillance of Chemotherapy for Improving Cardiovascular Outcomes" (SUCCOUR) randomized controlled trial did not meet its primary outcome, as there was no difference in the continuous measure of heart function for all patients in the LVEF-guided and GLS-guided arms in both treated and untreated patients.

However, what's of clinical importance are the patients whose abnormal change in heart function resulted in the initiation of therapy.

In these patients, the use of GLS-monitoring led to a lower reduction in heart function versus traditional monitoring. It also reduced the risk of cardiotoxicity, and heart damage was detected earlier and in twice the number of participants.

For oncologists and cardiologists, one of the primary concerns is how to prevent the development of cardiotoxicity in patients. The secondary outcome of the SUCCOUR trial proves by using GLS to monitor heart function and intervening with cardioprotective therapy when damage is detected, further reduction in heart function can be prevented and the risk of cardiotoxicity reduced.

"The purpose of a sensitive method like GLS is to pick up the presence of disease and treat it early," says Dr. Thavendiranathan. "This means more patients will be treated, and if we start heart medications when a change is identified, we can prevent significant worsening of heart function."

Sindhu, who was randomized into the GLS arm, joined the SUCCOUR trial knowing it may reduce the degree of cardiotoxicity she could potentially develop.

When a change in measurement alerted Dr. Thavendiranathan that the cancer therapy was damaging her heart, he initiated cardio-protective therapy - drugs that help improve heart function and prevent further damage.

By the end of her treatment, Sindhu's heart function returned to normal and she did not develop cardiotoxicity.

"Our findings suggest we should consider changing how we follow patients during cancer therapy and add GLS to routine heart surveillance," says Dr. Thavendiranathan, who co-led the study at 28 centres with Dr. Thomas Marwick of the Baker Heart and Diabetes Institute, and Dr. Tomoko Negishi of the Menzies Research Institute.

Dr. Thavendiranathan would like to see the GLS-measurement approach implemented in clinical practice.

"This trial gave me hope, and I'm thankful to say I'm now doing well and the cancer treatment worked," says Sindhu. "Dr. Thavendiranathan is an excellent physician and researcher, and I'm very thankful to him."

Scientists at The Marine Mammal Center - the world's largest marine mammal hospital - have found that viral-caused cancer in adult California sea lions is significantly increased by their exposure to toxins in the environment. The study is the result of over 20 years of research and examination of nearly 400 California sea lion patients by The Marine Mammal Center.

The Marine Mammal Center has been on the forefront of researching and understanding cancer in California sea lions and its connection to both ocean and human health. Since the cancer in sea lions was first discovered in 1979, between 18-23 percent of adult sea lions admitted to the Center's hospital have died of the fatal disease - the highest prevalence for a single type of cancer in any mammal, including humans.

The study, which was published in Frontiers in Marine Science, a peer-reviewed research journal, concluded that efforts to prevent ecosystem contamination with pollutants must improve in order to prevent virally caused cancer development in both wildlife and humans.

"This paper's conclusions mark a significant milestone in piecing together the complicated puzzle of cancer development in California sea lions," said Dr. Pádraig Duignan, Chief Pathologist at The Marine Mammal Center and co-author of the study. "The decades of research looking into this deadly disease clearly shows the ocean environment we all share is in trouble and that we need to find solutions to protect our collective health."

The findings also show that California sea lions have among the highest levels of certain persistent organic pollutants in the blubber of any marine mammals - a disturbing report that is cause for concern for scientists across the globe.

"Even though some of the pollutants we're finding in the blubber have been out of use for years, these cancer-causing elements remain in the environment for a very long time and wreak havoc on opportunistic coastal feeders like sea lions," said Dr. Duignan. "It concerns me knowing that we consume very similar seafood as these cancer victims and that the ocean is raising a loud and clear alarm in the sick bodies of a sentinel species. We need to continue this critical research and collaborate with the human cancer doctors to find patterns to help discover the link between sea lions and ourselves."

Previously, researchers at The Marine Mammal Center determined that these sea lions are infected with a herpesvirus similar to one that causes Kaposi's sarcoma (a viral cancer) in humans. In this newly released study, scientists used complex statistical analysis and modeling to investigate the relative roles of the various factors in the development of fatal metastatic cancer. The results showed that the damage of the DNA in sea lions occurs due to a number of factors, including:
* the interaction of many environmental factors, including chemical contaminants and pollutants; and
* infections by tumor-promoting viruses like Otarine herpesvirus-1.

Additionally, their findings found that the animals' own genetic predisposition was not a significant factor to developing the cancer.

"While there is more to be learned about the complex factors that play into the development of this disease, what we learn from these animals contributes to research that underpins the threat to human health from pollutants in the ocean," said Dr. Frances M. D. Gulland, the lead author of the study who worked at The Marine Mammal Center for 25 years.