Thanks for your reply.

The issue is that we need to refresh some vertices mid transaction. Rolling back is not an option as that would erase edits that we're making in our transaction. Disabling tranaction cache could be one solution. Using a treaded tx counld be an option as well as that transaction does see edits made by other users, opposed to the original transaction:
A reads vertex X and then starts transaction and makes edits, does not commit yet
B may or may not edit X
A continues editing and before committing it needs to makes sure vertex X was not changed by B or else rolls back.
Again, it is possible to read X by using a ThreadedTx but I'm interested if there's another way to refresh a vertex mid transaction.

Kr,
Timon