* Euro STOXX 600 gains 0.1%
* Mixed picture for European earnings
* Yen slips to 4-year low as risk sentiment improves
* Bitcoin near all-time high
* Oil prices near multi-year peak, China coal tumbles
By Tom Wilson and Hideyuki Sano
LONDON/TOKYO, Oct 20 (Reuters) - Shares from Asia to Europe gained on Wednesday on rising optimism about the global economy and corporate earnings, while government bond yields rose and the yen fell to its lowest in four years against the dollar.
The regional Euro STOXX 600 traded up 0.1% after opening in negative territory, amid a somewhat mixed picture for earnings even as investors were largely upbeat about prospects. German stocks also turned positive, adding 0.3%.
In the Netherlands, chip-making machine maker ASML Holdings , a key supplier to computer chip makers, fell 3% despite posting slightly better-than-expected quarterly results. Swiss food giant Nestle gained 3% after it raised its sales outlook.
Earnings reports will be in full swings in many countries over coming weeks. Tesla is among companies that will release results later on Wednesday.
"Some volatility should be expected in a time when you have the earnings season, you have a multiplicity of shocks going through the system," said Sebastien Galy, senior macro strategist at Nordea Asset Management.
"The long-term outlook is actually quite good. The economies are slowing down but going quite well."
U.S. futures gauges suggested that Wall Street would open flat. MSCI's world equity index , which tracks shares in 50 countries, also traded flat.
The positive mood in Asia and a day earlier in the United States nevertheless saw government bond yields rising further.
Euro zone yields steadied as recent comments by European Central Bank officials failed to soothe fears of a potential monetary tightening.
The 10-year U.S. Treasuries yield climbed at one point to as high as 1.673%, a level last seen in May. It last stood at 1.64%. Shorter yields dipped, however, with the two-year yield slipping to 0.39% from Monday's peak.
"Whilst inflation concerns are still very much bubbling under the surface of markets, risk appetite strengthened further thanks in no small part to decent earnings reports," Deutsche Bank analysts wrote in a note.
"There are no signs of widespread erosions of margins at the moment. Perhaps there is so much money sloshing about that for now prices are broadly being passed on."
MSCI's broadest index of Asia-Pacific shares outside Japan rose 0.5%, led by 1.1% gains in Hong Kong.
Investors expect the Federal Reserve to announce tapering of its bond buying and money markets futures are pricing in one U.S. rate hike later next year.
"The Fed is likely to become more hawkish, probably tweaking its language on its assessment that inflation will be transient," said Naokazu Koshimizu, senior strategist at Nomura Securities.
"While the Fed will maintain tapering is not linked to a future rate hike, the market will likely try to price in rate hikes and flatten the yield curve."
In the currency market, a rise in long-term rates pushed the dollar to close to a four-year high against the yen. The greenback climbed as high as 114.585 yen for the first time since November 2017.
Bitcoin stood at $63,937, near its all-time peak of $64,895 as the first U.S. bitcoin futures-based exchange-traded fund began trading on Tuesday.
Oil prices eased slightly but held near multi-year peaks as an energy supply crunch persisted across the globe.
Brent crude futures dropped 61 cents, or 0.6%, to $84.47 a barrel, while U.S. crude futures traded at $82.33 per barrel, down 0.7% on the day but near Monday's peak of $83.18, the highest level since 2014.
(Reporting by Tom Wilson in London and Hifeyuki Sano in Tokyo; Editing by Catherine Evans)