In order to get a Visa in the United States you must show a substantial investment. In addition you HAVE to show where the money is coming from.
Gifts can count as long as the person gifting you the money can show where the funds come from.
Loans are never recommended from a US Bank! A loan from a foreign bank can be used if its secured from real estate or personal items with a high value. If no security behind it the US Embassy will look unfavorably.