This is a set of web collections curated by Mark Graham using the Archive-IT service of the Internet Archive. They include web captures of the ISKME.org website as well as captures from sites hosted by IGC.org.These web captures are available to the general public.For more information about this collection please feel free to contact Mark via Send Mail ||||| Despite significant advances in the fabrication of bioengineered scaffolds for tissue engineering, delivery of nutrients in complex engineered human tissues remains a challenge. By taking advantage of the similarities in the vascular structure of plant and animal tissues, we developed decellularized plant tissue as a prevascularized scaffold for tissue engineering applications. Perfusion-based decellularization was modified for different plant species, providing different geometries of scaffolding. After decellularization, plant scaffolds remained patent and able to transport microparticles. Plant scaffolds were recellularized with human endothelial cells that colonized the inner surfaces of plant vasculature. Human mesenchymal stem cells and human pluripotent stem cell derived cardiomyocytes adhered to the outer surfaces of plant scaffolds. Cardiomyocytes demonstrated contractile function and calcium handling capabilities over the course of 21 days. These data demonstrate the potential of decellularized plants as scaffolds for tissue engineering, which could ultimately provide a cost-efficient, “green” technology for regenerating large volume vascularized tissue mass. ||||| Researchers at the Worcester Polytechnic Institute are developing a method to use the vascular network in spinach leaves to deliver blood, oxygen and nutrients to grow human tissue. (Myocardial Regeneration Lab, Worcester Polytechnic Institute) 
 
 If an overhyped vegetable existed before marketers coined the term superfood — and long before Oprah Winfrey chatted up acai berries with Dr. Oz — look no further than spinach. (Here’s to Popeye, eating the stuff by the can to inflate his biceps.) Spinach alone, of course, won’t pump anyone up. But it does have a few physical properties of the type that excite biomedical engineers. Spinach grows a network of veins, for instance, that thread through its leaves in a way similar to blood vessels through a human heart. 
 
 These leafy veins allowed researchers at Massachusetts’s Worcester Polytechnic Institute to give a new meaning to heart-healthy spinach. The tissue engineers, as they reported recently in the journal Biomaterials, stripped green spinach leaves of their cells. The spinach turned translucent. The scientists seeded the gaps that the plant cells left behind with human heart tissue. Heart cells, in clusters, beat for up to three weeks in this unusual environment. 
 
 The inspiration for the human-plant fusion came over lunch — and, yes, the leafy greens were involved — when WPI bioengineers Glenn Gaudette and Joshua Gershlak began to brainstorm new ways to tackle a deadly medical problem: the lack of donor organs. Of the more than 100,000 people on the donor list, nearly two dozen people die each day while waiting for an organ transplant. 
 
 To meet the demand, scientists have tried to create artificial organs through innovations such as 3-D-printing tissue. So far, however, no one has been able to print a perfect heart. 
 
 “One of the big problems in engineering heart muscle is getting blood flow to all of the cells,” Gaudette, a professor of biomedical engineering at WPI, told The Washington Post. “Heart muscle is pretty thick.” Current technology cannot construct tissue dense enough to replace a damaged heart while also allowing for the tiny blood vessels needed to deliver life-giving oxygen. 
 
 Rather than creating minuscule blood vessels, the scientists decided to borrow from what nature already evolved. First, they removed the cells from spinach leaves purchased at a local market. “We use detergent — soaps — which strips away the cellular material of tissues,” said Gershlak, a WPI graduate student in Gaudette’s lab. “This leaves behind the protein matrix and structure.” The soap punctured plant cell membranes and washed the deflated cells away; the overall effect was not unlike turning over a garden before planting new crops. 
 
 Left behind was cellulose, a plant material known to be compatible with mammal tissue, as well as the intact leaf veins. The scientists seeded the now-vacated cellulose matrix with cardiac muscle cells. After five days, the muscle cells began to beat. 
 
 It was not quite as if researchers grew an entire slab of quivering muscle from spinach. And, though the scientists watched red liquid course through the spinach veins, this was dye, not blood. But to witness individual human cells contracting on a spinach leaf, via microscope, was exciting enough for Gaudette to whip out his cellphone and began recording in grainy video. 
 
 “It was definitely a double take,” Gershlak said, of discovering the beating muscle cells. “All of a sudden you see cells moving.” 
 
 This was not the only instance in which researchers cultivated human tissue on a plant scaffold. Recently, a team of Ottawa scientists stripped an apple of its plant cells, carved a fruit slice to look like a human ear and filled its extracellular matrix with cervical tissue. 
 
 But Gershlak, Gaudette and their colleagues were the first, they said, to use the technique in an attempt to repurpose plant veins. They poured tiny spheres through the spinach leaves. Beads 10 microns in diameter, a size on par with red blood cells, successfully flowed through the vein network. 
 
 Though these early experiments served as proof-of-concept work, Gaudette said the study could be the foundation for stitching the veins of spinach leaves to human blood vessels. “Long term, we’re definitely envisioning implanting a graft in damaged heart tissue,” he said. 
 
 But the researchers first need to make sure that plant scaffolds like these would not be rejected, once inside a host. They also plan to make their heart-spinach hybrids stronger. “If we stack decellularized leaves, can we create a large thickness,” Gaudette wondered, “more along the thickness of a human heart wall?” 
 
 One advantage of working with plants was the cornucopia of options at the scientists’ disposal. In the new report, the biomedical engineers successfully stripped plant cells from parsley, peanut hairy roots and a species of wormwood in addition to spinach. The biomedical engineers imagined that a piece of broccoli or cauliflower, once stripped of its cells, could be a foundation for growing lung tissue. And researchers in Wisconsin, collaborating with the WPI lab, recently strolled through their campus arboretum, plucking exotic leaves to test. 
 
 More from Morning Mix: 
 
 Evolutionary study unravels mystery of how cobras evolved their flesh-eating venom 
 
 Woman believed to be the first to have a baby using ovary frozen before puberty 
 
 Meet the mesentery: Irish scientists say this gut membrane should be upgraded to an organ
– Popeye knew a thing or two about building muscle, maybe even more than we realized. Per National Geographic, scientists have appropriated the cartoon character's favorite snack—a spinach leaf—to help create new human heart muscle. In doing so, they circumvented a tissue issue that's plagued this type of regenerative medicine and carved a path toward facilitating organ repair down the road. The study published in the Biomaterials journal details that challenge: even though researchers have been able to formulate human heart tissue in a lab, working up the vessels to deliver nutrients to that tissue has been problematic. "The main limiting factor … is the lack of a vascular network," study co-author Joshua Gershlak says in a video on the study. Which is where Popeye's plant food comes in. Scientists at Worcester Polytechnic Institute took a spinach leaf—with its own system of tiny veins to keep it fed and hydrated—removed its plant cells, and then immersed the leaf in a bath of human cells, using the leaf as a "scaffolding" of sorts. They pumped fluids and microparticles through the leaf's veins to demonstrate how oxygen could one day similarly flow through such a vascular system to keep human heart tissue healthy. The researchers were even able to see clusters of the cells "beating" within the leaf. "It was definitely a double take," Gershlak says, per the Washington Post. He and co-author Glenn Gaudette, both bioengineers, came up with the idea while eating lunch one day (which included spinach) and talking about the dearth of donated organs. (In the meantime, please wash that dirty spinach before you chow down.)