Note 8 - Stockholders' Equity (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2017

Dec. 31, 2016

Notes Tables

Share-based Compensation, Activity [Table Text Block]

	Number of Shares			Weighted Average Exercise Price
Outstanding at December 31, 2016		3,499,475		$	1.21
Granted		--			--
Exercised		--			--
Forfeited or expired		(115,200	)		17.75
Outstanding at March 31, 2017		3,384,275		$	0.64
Exercisable at March 31, 2017		2,191,281		$	1.69

	Number of Shares		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (yrs)		Aggregate Intrinsic Value
Outstanding at December 31, 2015		1,705,500	$	2.41
Granted		1,793,975		0.07
Exercised		-		-
Forfeited or expired		-		-
Outstanding at December 31, 2016		3,499,475	$	1.21		8.2	$	-0-
Exercisable at December 31, 2016		1,299,394	$	3.12		5.5	$	-0-

Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]

	Number of Shares			Weighted Average Exercise Price
Outstanding at December 31, 2016		32,751,578		$	0.07
Granted		--			--
Exercised		(983,334	)		0.05
Forfeited or expired		(1,112,001	)		0.57
Outstanding at March 31, 2017		30,656,243		$	0.05
Exercisable at March 31, 2017		30,656,243		$	0.05

Expiration Date	Number of Shares		Weighted Average Exercise Price
January 16, 2017		45,000		1.00
January 31, 2017		567,001		1.00
March 21, 2017		1,483,334		0.05
February 27, 2020		30,656,243		0.05
Outstanding and exercisable at December 31, 2016		32,751,578	$	0.07

Schedule of Stock by Class [Table Text Block]

Series B Convertible Preferred Stock	285,714
Series C Convertible Preferred Stock	57,363,520
Common Stock Purchase Warrants	30,656,243
Equity Incentive Plans	4,590,300
Total	92,895,777

Stock Purchase Warrants	32,751,578
Stock Option Plans	4,705,500
Series B Convertible Preferred Stock	285,714
Series C Convertible Preferred Stock	57,363,520
Total	95,106,312