d3 dendogram, is there a way to make a single node standout?

d3 dendogram, is there a way to make a single node standout?

I am using this exact code into our website (code is at the bottom of the
webpage)
http://bl.ocks.org/mbostock/4063570
I am wondering if there is a way to add a json attribute to send back and
modify the javascript such that one node is much much more bold than all
the other nodes(perhaps a bigger circle or bigger bold font) such that it
is obvious that this is the selected node.
thanks, Dean