Yes I have. Plug one end and pour Epoxy into the hollow. Let it sit and soak in for about ten minutes or so (depending on pot life of your Epoxy). Pour out the excess. Soak a pre-fitted piece of dowel and then slide it into the bamboo tube so that it ends up centered. Allow the Epoxy to cure. It is a good idea to cure the tube lying flat and roll it periodically as the Epoxy sets up so that it doesn't pool on one side of the tube. You can also cap the ends of the tube. You may just be able to fit some wooden nail or screw plugs which you can buy pre-made from any Home Depot etc.
That will give it a finished look to match the general natural look.
eta: Here's what i mean by screw plugs or "buttons": http://www.widgetco.com/wood-buttons