Periscope surfaces Twitter above key $50 level

Periscope app
Source: Periscope
Periscope app

A bullish reaction to live video application Periscope pushed Twitter shares up 5 percent in one week, to above a key level of resistance at $50 a share.

Wall Street gave the final boost Wednesday, as a bullish note from Jefferies boosted Twitter's stock as much as 3 percent in morning trading to break $51 a share.