Could reanimation be possible

Answer 1

Not at this time. There are many problems that accompany cell death, freezing, and attempts at reanimation.
When speaking of freezing people and then reviving them, the problem is that ice crystals form in tissues, and those crystals destroy cell membranes, killing the cells (often the case in frostbite). That is why flash-freezing with liquid nitrogen is necessary. However, replacing water in plasma with antifreeze-like fluid (not antifreeze itself, which is toxic, but rather glycerol or dimethyl sulfoxide) so that it can perfuse throughout tissues, allows for the body to be frozen quickly to slow cellular activity, preventing oxidative stress and destruction of cell structures and enzymes.

The biggest problems come from the actual reanimation process itself, as you have to replace those fluids and reheat the body in sufficient time so that enzymatic activity, metabolic activity, nerve activity, etc. are restarted at the same time so that the cells don't begin to breakdown. Since there are many mechanisms in place in cells that chemically/enzymatically detect cellular impairment, such states usually trigger apoptosis, whereby the cell destroys itself. On the whole, this results in tissue death.

If you could solve the above problems, then it could, in theory, be possible to slow cellular/enzymatic activity enough to preserve someone...and then reheat the body and restart these processes to allow them to continue without excessive cell/tissue death. However, at the moment, this is not possible.