Stop your sobbing – because scientists can do it for you. Using stem cells, Dutch researchers have grown miniature human tear glands capable of "crying".

Initially, when scientists were looking at developing this technology, their first port of call was the inner lining of the gut, because it replaces itself every five days. They took a tiny piece of gut tissue filled with stem cells and fed it proteins called growth factors to stimulate cell growth, expecting the stem cells to rapidly proliferate.

"But to our surprise, the stem cells created a mini-organ … it's small, but it has all the different cells in the gut that you need for digesting food," said the study author Hans Clevers, group leader at the Hubrecht Institute for developmental biology and stem cell research and at the Princess Máxima Center for pediatric oncology.