Pandas: Calculate value changes with diff based on condition

Question

Expanding a bit on this question, I want to capture changes in values specifically when the previous column value is 0 or when the next column value is 0.

Given the following dataframe, tracking value changes from one column to the next using diff and aggregating these fluctuations in a new set of values is possible.

Item    Jan_20  Apr_20  Aug_20  Oct_20
Apple       3       4       4       4
Orange      5       5       1       2
Grapes      0       0       4       4
Berry       5       3       0       0
Banana      0       2       0       0

However, if I were to only capture such differences when the values being changed from one column to the next is either specifically from 0 or to 0 and tracking that as either new fruit or lost fruit, respectively, how would I do that?

Desired outcome:

Type                Jan_20  Apr_20  Aug_20  Oct_20
New Fruits              0        2       4      0
Lost Fruits             0        0       5      0 

Put another way, in the example, since Grapes go from a value of 0 in Apr_20 to 4 in Aug_20, I want 4 to be captured and stored in New Fruits. Similarly, since Banana and Berry both go from a value higher than zero in Apr_20 to 0 in Aug_20, I want to aggregate those values in Lost Fruits.

How could this be achieved?