DNA glue directs tiny gel ‘bricks’ to self-assemble

first_imgA team of researchers at the Wyss Institute of Biologically Inspired Engineering at Harvard University has found a way to self-assemble complex structures out of gel “bricks” smaller than a grain of salt. The new method could help solve one of the major challenges in tissue engineering: creating injectable components that self-assemble into intricately structured, biocompatible scaffolds at an injury site to help regrow human tissues.The key to self-assembly was developing the world’s first programmable glue. The glue is made of DNA, and it directs specific bricks of a water-filled gel to adhere only to each other, the scientists report in the Sept. 9 online issue of Nature Communications.“By using DNA glue to guide gel bricks to self-assemble, we’re creating sophisticated programmable architecture,” said Peng Yin, a core faculty member at the Wyss Institute and senior co-author of the study. Yin is also an assistant professor of systems biology at Harvard Medical School (HMS). This novel self-assembly method worked for gel cubes as tiny as a piece of silt (30 microns diameter) to as large as a grain of sand (1 millimeter diameter), underscoring the method’s versatility.The programmable DNA glue could also be used with other materials to create a variety of small, self-assembling devices, including lenses and reconfigurable microchips as well as surgical glue that could knit together only the desired tissues, said Ali Khademhosseini, an associate faculty member at the Wyss Institute who is the other senior co-author of the study.“It could work for anything where you’d want a programmable glue to induce assembly of higher-order structures, with great control over their final architecture — and that’s very exciting,” said Khademhosseini, who is also an associate professor at Harvard-MIT’s Division of Health Sciences and Technology, Brigham and Women’s Hospital, and Harvard Medical School.To fabricate devices or their component parts, manufacturers often start with a single piece of material, then modify it until it has the desired properties. Other times they employ the practice used by auto manufacturers, making components with the desired properties, then assembling the components to produce the final device. Living organisms fabricate their tissues using a similar strategy, in which different types of cells assemble into functional building blocks that generate the appropriate tissue function. In the liver, for example, the functional building blocks are small tissue units called lobules. In muscle tissue, the functional building blocks are muscle fibers.  Scientists have tried to mimic this manufacturing strategy by developing self-assembling systems to fabricate devices.Last year Yin, and his team reported in Science that they had developed minuscule DNA bricks, smaller than the tiniest virus, that could self-assemble into complex, nanoscale 3-D structures. He and Khademhosseini sought to create a similar, programmable, self-assembling system for mesoscale components — those with edge widths ranging from 30 microns to 1,000 microns (1 millimeter). They focused first on creating a self-assembly system in which bricks of biocompatible, biodegradable gels called hydrogels assembled into complex structures. In future applications, small hydrogel bricks containing human cells could potentially be injected into the body. The bricks would assemble, then the cells would knit together to form functional tissue as the hydrogels broke down.In previous attempts to self-assemble hydrogel bricks into complex structures, the bricks often stuck to one another rather than assembling into the desired architecture. Yin and Khademhosseini needed a way to help each component stick only to specific partners, and to no other components. In other words, they needed programmable glue.DNA was ideal for the task. It stores genetic information as a sequence of four chemical “letters,” or nucleotides, that bind in a specific way to complementary nucleotides (A to T, and C to G). A single strand of DNA adheres tightly to a second strand, but only if the second strand has a sequence of nucleotides that is complementary to the first. And even a short piece of DNA can have a huge number of possible sequences, which makes the glue programmable.The researchers used enzymes to multiply a snippet of DNA into long pieces called “giant DNA” that contained multiple copies of that snippet. When they coated hydrogel cubes with giant DNA, the cubes adhered only to partner cubes coated with matching giant DNA. Because scientists can synthesize snippets of DNA with any sequence they want, the giant DNA functioned as programmable DNA glue.To assemble hydrogel cubes into larger structures, they used smaller hydrogel cubes as connectors. They coated the connector cube with their DNA glue, then attached it to one of the six faces of a larger cube.  A large cube outfitted this way adhered only to other large cubes whose connectors had matching DNA glue.By placing connector cubes on various faces of the larger cubes, they programmed larger cubes to self-assemble into specific shapes, including a matching pair of cubes, a linear chain, a square, and a T-shaped structure.The method was so specific that when the researchers placed 25 pairs of matched cubes in a single pot, all the cubes located and adhered only to their partners. This ability to assemble multiple components simultaneously is called multiplexity, and the results show that the new system has the highest degree of multiplexity of all existing mesoscale self-assembly systems.“Designing a strategy that leverages the power of self-assembly used by living systems to direct construction of tissues from tiny component parts represents an entirely new approach for tissue engineering,” said Don Ingber, the Wyss Institute’s founding director.“Peng and Ali have created an elegant and straightforward method that could permit tissues to be reconstructed from within after a simple injection, rather than requiring major surgery.”This work was funded by the National Institutes of Health, the Office of Naval Research, the National Science Foundation, and the Wyss Institute. In addition to Yin and Khademhosseini, the research team included Hao Qi, a postdoctoral fellow at the Wyss Institute; Majid Ghodousi, a research assistant at the Wyss Institute; Yanan Du, a former postdoctoral fellow at the Wyss Institute who is now a professor of biomedical engineering at Tsinghua University in Beijing; Casey Grun, an undergraduate researcher at the Wyss Institute; and Hojae Bae, a former instructor of medicine at Harvard Medical School who is now an assistant professor of bioindustrial technologies at Konkuk University in South Korea.last_img read more

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‘REDEFINING’ Converged Infrastructure at EMC World 2014

first_imgMay 5 at EMC World in Las Vegas, VCE™ will highlight the latest and greatest in converged infrastructure to simplify the journey to the cloud. With in-depth product demonstrations, customer testimonies and technical sessions, EMC World will give attendees an inside look at how VCE is redefining IT.VCE will have a strong presence at this year’s event with presentations at our booth and on stage. Don’t miss Jeremy Lawrence of Eclipse Aerospace and VCE’s own John Lockyer on Wednesday, May 7 from 8:30 – 9:30 a.m. in Liddo 3005, discussing the challenges Eclipse faced in its data center and their firsthand transformational experience with the Vblock™ System.EMC is featuring VCE in its Build-A-Hybrid-Cloud LIVE in the Solution Pavilion (Booth #850). In addition to 19 live demonstrations of IaaS, PaaS and Hybrid Cloud use-cases, VCE and EMC will build a cloud – from crate to operational – in 48 hours on the show floor. Attendees will learn how to transform their infrastructures to deliver cloud services. The demonstration will prove how customers and partners can quickly and easily realize business value through Vblock Systems. Our ability to help enterprises rapidly deliver cloud services on-demand while reducing costs and simplifying operations is second to none.VCE will also be featured on theCUBE, live at the EMC Square outside the Solutions Pavilion. Several VCE executives, partners and customers will be discussing how Vblock Systems can transform IT:Praveen Akkiraju, Chief Executive Officer, VCE – May 6 at 12:20 p.m. PTTodd Pavone, Executive Vice President of Product Development and Strategy, VCE – May 6 at 3:40 p.m. PTChristen Lewis, Principal Cloud Architect, Apollo Education Group, and Charles Preston, Principal Cloud Architect, Apollo Education Group – May 6 at 4:20p.m. PTDave Hart, Executive Vice President and Chief Operating Officer, Presidio – May 6 at 4:40 p.m. PTJason Mendenhall, Executive Vice President, Cloud, Switch Communications – May 7 at 11:00 a.m. PTVCE Booth #210 will be a busy place throughout the conference, with VCE customers, including Apollo Education Group, University of San Diego and Switch Communications, presenting their experiences with Vblock Systems. They’ll be on hand to talk through their strategic decisions to embrace VCE converged infrastructure and discuss the results they’ve seen. In addition, there will be VCE technology demos and white boards.For those wanting a closer look at what makes a Vblock System so special, don’t miss the VCE™ Vision Intelligent Operations Hands-On Lab. VCE Vision innovation enables converged operations of Vblock Systems.With Vblock Systems demonstrated across the show floor in our partner company booths as well as our own, VCE will make a big impact at this year’s EMC World. Those looking for a sneak peak of VCE at EMC World should keep a close eye on our Vblog and events page. VCE experts will be blogging before and during the event, providing insights and analysis of presentations and EMC World keynotes. We hope to see you there!last_img read more

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John Adams, 86

first_imgJohn R. Adams, 86, of Ruskin, Florida, formerly of Versailles passed away Sunday, May 1, 2016 at Life Path Hospice in Ruskin. He was born in Indianapolis on February 27, 1930 the son of John and Georgia McDonald Adams. He was married to Mayme Gurney and she preceded him in death on October 20, 1984. He was married to Lucille Buchanan on August 10, 1985 and she survives. Other survivors include one son John S. Adams of Tampa, Florida; one daughter Crystal Kormelink of Cincinnati; five step-sons Mark (Dianne) Ogden of Atlanta, Georgia, Gary (Jody) Ogden, and Paul Ogden of Indianapolis, Jeff Ogden of Clearwater, Florida,  and Mike (Judy) Ogden of Overland Park, Kansas; 11 grandchildren and one great-grandchild; one brother Dale (Martha) Adams of Herndon, Virginia; two sisters Stella Dobson of Rising Sun, and Alta Holcomb of Versailles. He was also preceded in death by his parents, his brothers Edward and Grover, and his sisters Betty Holzer and Velma Browning. Mr. Adams was a 1949 graduate of Holton High School. He was a veteran of the Korean War serving with the US Army and rising to the rank of Corporal and for his service John received the National Defense Service Medal. In civilian life he worked at Ft. Knox, Kentucky and retired in 1990 from the Jefferson Proving Ground where he worked in demolition. John was member of St. Anne Catholic Church in Ruskin and was a 50 year member of the Versailles Masonic Lodge. Mass of Christian Burial will be held on Saturday, May 7th at 1pm at St. John Catholic Church in Osgood with Father Don Buchanan officiating.  Burial will be in the Marble Corner Cemetery at Versailles. Visitation will be Friday from 5pm to 7pm at the Stratton-Karsteter Funeral Home in Versailles with Rosary services at 6:45pm and Masonic services at 7pm. Memorials may be given to the Moffitt Cancer Center or the Shriner’s Hospital in care of the funeral home.last_img read more

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Masters set for dramatic finale

first_img Luiten birdied four of the last five holes to finish four over par on his tournament debut, taking advantage of some more generous pin positions than in Saturday’s third round. “It feels really good to shoot 67 on Sunday at the Masters,” said Luiten, who made the halfway cut on the mark of four over before a third round of 77. “I look at my tournament and I’m very happy. Yesterday was a little bit of an off day, and in the future you need four good days to compete here. “It felt like they watered the greens a little bit overnight. They were a little bit slower and a little bit more forgiving than yesterday when they were very slick and quick. “So it felt like they set it up a little bit easier, but there were still a lot of tough pin positions and you just have to play smart to some of them and take your par and then go on to the next.” Former champion Bubba Watson and fellow American Jordan Spieth shared the lead on five under par heading into the final round, the 20-year-old Spieth looking to become the youngest ever Masters champion and first to win on debut since Fuzzy Zoeller in 1979. At the other end of the spectrum, 50-year-old Spaniard Miguel Angel Jimenez was aiming to become the oldest winner of any major and the first European to claim a green jacket since his compatriot Jose Maria Olazabal in 1999. Jimenez got off to a poor start with a bogey on the first, but a superb bunker shot on the par-five second set up a birdie to get him back to three under. Playing partner Rickie Fowler had birdied the first, only to three-putt the second from just eight feet to drop back to three under alongside Denmark’s Thomas Bjorn, who had birdied the third. England’s Lee Westwood, seeking a first major title at the 64th attempt, had dropped back to one under after a bogey on the third. Westwood’s chances suffered a potentially decisive blow with a double bogey on the fourth which left him one over par, one shot behind Ryder Cup team-mate Rory McIlroy. Joost Luiten finished his final round of the 78th Masters as the leaders set off, but the Ryder Cup hopeful’s superb 67 suggested an exciting finale was in store at Augusta National. McIlroy, who suffered the embarrassment of being outscored by his marker on Saturday, had been four over after a bogey at the fourth, but then birdied the seventh, eighth, ninth and 11th to get back to level par. Defending champion Adam Scott was also level, the Australian recovering from two early bogeys to also card a hat-trick of birdies from the seventh. That was six off the lead held by Spieth, who had birdied the second, with Matt Kuchar also six under before four-putting the fourth for a double bogey. Press Associationlast_img read more

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Marial Shayok increases physicality to become a top threat for No. 9 Virginia

first_imgMarial Shayok said he doesn’t take a single minute on the court for granted. Especially since before this year, he wasn’t getting many.Despite a rich basketball family, Shayok began his career at Virginia as a minimal contributor. Now, his scoring average has more than doubled and he leads his team in his percentage of shots taken when on the floor (30.1), per Kenpom.com.“We have gone to a more physical lineup and he has played well,” head coach Tony Bennett said. “Marial has always shown good stretches, but I think he is getting more comfortable and establishing his spot.”Shayok showcased the difference against Georgia Tech on Jan. 21. Late in the game, Shayok caught a pass at the elbow after skirting an off-ball screen. He busted through the defense, absorbed a whack on the arm and laid the ball in off the glass for an and-1. Shayok walked calmly to the charity stripe while the Cavaliers home crowd applauded him for totaling a new career-high in points (19).Shayok has always exhibited that composure on the court. His quiet but aggressive style has him in the middle of his most successful season yet. Shayok averages a career high in both points (10.1) and minutes (21.1) per game and has become an essential piece of the No. 9 Virginia (17-4, 7-2 Atlantic Coast) team that visits the Carrier Dome this Saturday at noon.AdvertisementThis is placeholder text“He’s always been a scorer,” teammate Devon Hall said. “I think him being patient … (and) letting the game come to him, I think that really changed for him this year.”It’s another development in a game that the Virginia guard has spent his life honing. His father Markur, sister Yar and brother Shayok Shayok all played basketball at the collegiate level. Marial Shayok watched his four older siblings play outside and gravitated to the sport. He eventually joined their daily games.Shayok grew up in Ottawa, Canada, though his father comes from Khartoum, Sudan. There, Markur belonged to the Dinka tribe responsible for NBA players Manute Bol and Luol Deng. Markur moved to the United States in 1986 to play basketball, fleeing Sudanese civil unrest and seeking a better life for his family. Shayok has never visited his parent’s home country, but he feels at peace with that.“I just try to rep family as best as I can,” Shayok said. “Everything I do is a testament to them.”This season, Shayok is doing just that. Bennett praised Shayok for his offensive consistency. The guard has become just one of the weapons in Virginia’s armory. He ranks third in points per game behind London Perrantes (12) and Austin Nichols (11). That’s a direct product of his increased physicality enabling him to attack the rim more often.Early in the first half against then-No. 1 Villanova, Shayok received a pass at the three-point line with only one defender between him and the rim. He put his head down and barreled toward the defender. A lowered shoulder knocked the defender to the ground before Shayok rose up and hit the floater. He left the celebration up to teammate Isaiah Wilkins while he strode to the line to finish his and-1.“Marial is wired to score,” Bennet said. “I am so happy to see him playing at this level and we will need it to continue.”This Saturday, Shayok will see some familiar faces in a sea of Orange as he goes to work. His parents usually watch every game on television, but now will make the two-hour drive from their home in Canada to visit the Dome.On the court, Shayok doesn’t feel obligated to follow in the footsteps of his family. He treats that notion with the same demeanor he’s had his whole career.“Definitely no pressure,” Shayok said. “… They instilled confidence in me. You just try to play free.” Comments Facebook Twitter Google+ Published on February 2, 2017 at 11:47 pm Contact Nick: [email protected] | @nick_a_alvarezlast_img read more

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