Nikkei drops to fresh 1-week low on weak U.S. shares; ANA shines

* ANA rises on increased traffic, CLSA's rating hike * Analysts see signs Japanese shares still overheated By Ayai Tomisawa TOKYO, July 9 (Reuters) - Japan's Nikkei share average fell to a fresh one-week low on Wednesday morning as U.S. stocks beat a retreat before the start of the earnings season, and the stronger yen hurt exporters. Bucking the weakness, ANA Holdings rose 1.3 percent after CLSA hiked its rating to 'buy' from 'outperform' citing its strong inbound and outbound