  This paper is devoted to the interplay between p-wave, s-wave pion-nucleon/
nucleus interaction and in-medium pion-pion interaction with special emphasis
on the role of the nuclear pionic scalar density driving a large amount of
chiral symmetry restoration. In particular we show that the $\pi NN$ coupling
constant and the Goldberger-Treiman relation are preserved in the nuclear
medium within certain conditions. We also discuss the related problem of the
in-medium pion-pion strength function.
