Seemingly, no:

Diplomatic Relations

As North Korea and the United States have no formal diplomatic relations, Sweden acts as the protecting power of United States interests in North Korea for consular matters.

More about it can be read here.

Economic Relations

From this page you can see that:

Most forms of U.S. economic assistance, other than purely humanitarian assistance, are prohibited. The United States has provided food and other emergency aid to North Korea during times of famine and natural disasters. The United States has also assisted U.S. NGOs in providing aid to fight the outbreak of infectious diseases and to improve farming practices and agricultural output in rural areas.

and

The United States imposed a near total economic embargo on North Korea in 1950 when North Korea attacked the South. Over the following years, some U.S. sanctions were eased, but others were imposed. In the wake of the DPRK’s cyber-attack targeting Sony Pictures Entertainment, Executive Order 13687 imposed new sanctions against the government of North Korea and the Korean Workers’ Party, effective January 2, 2015. U.S. economic interaction with North Korea remains minimal.

Seemingly, not many:

Diplomatic Relations

As North Korea and the United States have no formal diplomatic relations, Sweden acts as the protecting power of United States interests in North Korea for consular matters.

More about it can be read here.

Economic Relations

From this page you can see that:

Most forms of U.S. economic assistance, other than purely humanitarian assistance, are prohibited. The United States has provided food and other emergency aid to North Korea during times of famine and natural disasters. The United States has also assisted U.S. NGOs in providing aid to fight the outbreak of infectious diseases and to improve farming practices and agricultural output in rural areas.

and

The United States imposed a near total economic embargo on North Korea in 1950 when North Korea attacked the South. Over the following years, some U.S. sanctions were eased, but others were imposed. In the wake of the DPRK’s cyber-attack targeting Sony Pictures Entertainment, Executive Order 13687 imposed new sanctions against the government of North Korea and the Korean Workers’ Party, effective January 2, 2015. U.S. economic interaction with North Korea remains minimal.

Seemingly, no:

As North Korea and the United States have no formal diplomatic relations, Sweden acts as the protecting power of United States interests in North Korea for consular matters.

More about it can be read here.

Seemingly, no:

Diplomatic Relations

As North Korea and the United States have no formal diplomatic relations, Sweden acts as the protecting power of United States interests in North Korea for consular matters.

More about it can be read here.

Economic Relations

From this page you can see that:

Most forms of U.S. economic assistance, other than purely humanitarian assistance, are prohibited. The United States has provided food and other emergency aid to North Korea during times of famine and natural disasters. The United States has also assisted U.S. NGOs in providing aid to fight the outbreak of infectious diseases and to improve farming practices and agricultural output in rural areas.

and

The United States imposed a near total economic embargo on North Korea in 1950 when North Korea attacked the South. Over the following years, some U.S. sanctions were eased, but others were imposed. In the wake of the DPRK’s cyber-attack targeting Sony Pictures Entertainment, Executive Order 13687 imposed new sanctions against the government of North Korea and the Korean Workers’ Party, effective January 2, 2015. U.S. economic interaction with North Korea remains minimal.