You are speaking of Taxodium distichum or bald cyprus, if so then you might not in too bad of shape. The tree is deciduous so you might have just shocked it and it lost its leaves for the winter. Im in Florida and the bald cyprus and pond cyprus have all turned brown for the season. These trees are native to Florida and Mexico so the heat should not kill it, just might throw it in shock if its not used to it. I would just keep the plant watered, in the sun and see if it bounces back. I dont think there is much else to do.

Im not sure if this will help, but there is alot of info here.
http://pick5.pick.uga.edu/mp/20q?search=Taxodium+distichum

Ryan
I had a simular experiance with a Bald Cyress this past summer. I got back from a trip and found every leaf brown. I took it out of the nursery pot and set it in the shade, in the waters edge of a small pond. About month later it put back new green leaves , in time for Fall to knock them off. It seems healthy now , just dormant. (our winter)
I think I would put it in the shade and keep it moist. It will possibly come back. ( If watering was the original problem.)
Afterthought.
Since it probably still weak from the repotting , and now lost it's leaves. You might try a Peter Chan trick of , barerooting the tree , repotting it in long fibered spahgnum moss ,( Green , fresh if possible ) it the shade, kept moist.

This past summer I tried this on a sick Cryptomeria, and it seems to be working ( knock wood )
All the best.
Dave.