An anonymous reader quotes a report from Scientific American: Stomach ulcers and other gastric wounds afflict one in eight people worldwide, but common conventional therapies have drawbacks. Now scientists aim to treat such problems by exploring a new frontier in 3-D printing: depositing living cells directly inside the human body. [...] In their effort to treat stomach lesions less invasively, scientists in China wanted to develop a miniature bioprinting robot that could enter the human body with relative ease. The researchers used existing techniques for creating dexterous electronic devices, such as mechanical bees and cockroach-inspired robots, says the study's senior author Tao Xu, a bioengineer at Tsinghua University in Beijing. The resulting micro robot is just 30 millimeters wide -- less than half the width of a credit card -- and can fold to a length of 43 millimeters. Once inside a patient's body, it unfolds to become 59 millimeters long and can start bioprinting. "The team has constructed clever mechanisms that make the system compact when entering the body yet unfurl to provide a large working area once past the tight constrictions at entry," says David Hoelzle, a mechanical engineer at the Ohio State University, who did not take part in the study. In their experiments, the researchers in China fitted the micro robot onto an endoscope (a long tube that can be inserted through bodily openings) and successfully snaked it through a curved pipe into a transparent plastic model of a stomach. There, they used it to print gels loaded with human stomach lining and stomach muscle cells (which were grown in culture by a commercial laboratory) onto a lab dish. The printed cells remained viable and steadily proliferated over the course of 10 days. "This study is the first attempt to combine micro robots and bioprinting together," Xu says. The study has been published in the journal Biofabrication.Read more of this story at Slashdot. Click here to read full news..