preferred_name: choline(out) + n H(+)(in) <=> choline(in) + n H(+)(out)
preferred_name_lc: choline(out) + n h(+)(in) <=> choline(in) + n h(+)(out)
label: choline(out) + n H(+)(in) <=> choline(in) + n H(+)(out)
label_lc: choline(out) + n h(+)(in) <=> choline(in) + n h(+)(out)