Figure 8: Light micrographs of TUNEL staining of E. granulosus protoscoleces incubated in vitro with thymol and essential oils of T. vulgaris and O. vulgare. (a) Invaginated control protoscolex (16 hours p.i., 1280x). Note the integrity of the tegument (red arrow). (b)–(d) Protoscoleces showing TUNEL-positive nuclei (yellow arrowheads). (b) Evaginated protoscolex (thymol, 8 h p.i., 1700x). Note the presence of numerous apoptotic nuclei and the loss of the integrity of the tegument (red arrow). (c) Invaginated protoscolex with the presence of few TUNEL-positive nuclei (T. vulgaris, 16 h p.i., ×1500). (d) Protoscolex incubated with O. vulgare during 16 h (×1500). Few TUNEL-positive nuclei could be observed.