map   hard   nofile    1000
root    soft    nofile    1000
root    hard   nofile    1010
map   soft    nproc    1200
map   hard   nproc    1200
root    soft    nproc    180000
root    hard   nproc    180000

sed 's/^(roots*softs*nprocs*)180000$/140000/' file > newfile

sed -i 's/^(roots*softs*nprocs*)180000/140000/' file