Hemolytic uremic syndrome (HUS) is a condition characterized by destruction of red blood cells, low platelet count, and kidney failure. There are two types of HUS. Typical HUS follows a diarrheal infection often caused by E. coli OH157:H7.
Perhaps you mean what dynasty reigns in Japan. Akihito is the reigning Emperor of Japan, the 125th emperor of his line according to Japan's traditional order of succession. He acceded to the Chrysanthemum Throne in 1989. If you read wikipedia, you will observe a more balanced view of China's dynasty. Currently, and namely, there are 2 dynasties in China, with PRC being the de-facto ruling dynasty, with another less powerful ROC dynasty.
The Japanese monarchy is now the only monarchy to still use the title of Emperor. Monarchs, as a consequence, have come to seem as obsolete as court jesters or princesses in towers. For nine out of 10 people in the world, royalty is the stuff of fairy tales.