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Scientists say they have greatly advanced possibility of being able to reproduce body's organs via the use of 3D printing. Replacement organs could be created using new technique for bio-printing organic tissue. This allows scientists to create networks of thin tubes and vessels, like those used in our body for flow of blood and air. These are called vascular networks. Bio-engineering professor Jordan Miller explained why breakthrough was so important. He said: "One of biggest roadblocks to generating functional tissue replacements has been our inability to print complex [vascular networks] that can supply nutrients to densely populated tissues."

Professor Kelly Stevens of University of Washington wrote about difficulties scientists had in recreating vascular network. She said: "Tissue engineering has struggled with this for generation." She believes new breakthrough will allow medical practices to change in future. She asked: "If we can print tissues that look and now even breathe more like the healthy tissues in our bodies, will they also then functionally behave more like those tissues?" Professor Stevens said "This is important question, because how well bio-printed tissue functions will affect how successful it will be as therapy." Scientists hope this method will help millions of people waiting for organ transplant.

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