For heterostructured gradient materials, the engineered heterogeneity or gradient is mainly about two- and one-dimensional crystal defects such as intergranular and interphase boundaries, and dislocations, respectively. In this talk, we will present our recent studies of employing high-pressure torsion (HPT) technique in manipulating three- and zero-dimensional defects, namely, gas-filled pores in metals and oxygen vacancies in oxides, respectively. Sub-nanosized (1-10 nm) nitrogen-filled pores were introduced to copper during HPT process, and contributed to extraordinarily high thermostability in the ultrafine-grained Cu sample. In the other study, we uncover a gradient of oxygen vacancy concentration and concomitant bandgap narrowing in an individual zinc oxide nanoparticle processed by HPT.