If it's a Stream ( not a ValueStream) you have a DataChange event that you can subscribe to and for instance set a property on the ValueStream (increase a counter for instance) that you bind with TW 7.2 websockets feature to push it back to the mashup and refresh the mashup.
But it may not work as Streams ( and ValueStreams ) writes are Asynchronous, then you may receive the DataChange event and maybe the data it's not persisted, one thing that I don't really know if that DataChange event it's thrown when you modify the stream ( memory ) or the real write on the database it's done.
Best Luck,
Carles.
