Complex sentence: Surprisingly Dr. Dunlop's original work was initially ridiculed but before he dies it had become universally accepted, Dr. Dunlop had become the medical advisor to the government on genito-urinary diseases and his opinions, once controversial, are now a fundamental belief of modern medicine.
Split into simpler sentences: Surprisingly Dr. Dunlop's original work was initially ridiculed but before he died it had become universally accepted and Dr. Dunlop had become the medical advisor to the government on genito-urinary diseases. His opinions, once controversial, are now a fundamental belief of modern medicine.