Fig. 5

Ultrastructural level micrographs of schistosomula of S. mansoni at 72 h after exposure to AS, to RESV and to the combination of AS + RESV. In the control group, schistosomula exhibits intact tegument (T), spines (S), circular and longitudinal muscle (CM, LM) with a regular morphology. For NTS exposed to RESV, vesicles were seen in the tegument (arrows) along with some disorganization; no apparent damage occurred in subtegumental regions. In contrast, for schistosomula exposed to AS, loss of matrix integrity but without alterations to the tegument was apparent. The most prominent damage was seen on NTS treated with the combination of AS + RESV. Here, NTS displayed disruption and lysis of internal structures (arrowheads) and swelling of parenchyma tissues, disruption of tegument and disappearance of basal membrane (arrow), and the appearance of large vacuoles (asterisks). Abbreviations: T, tegument; S, spine; LM, longitudinal muscle; CM, circular muscle; Cb, cytoplasmatic bridge. Scale-bars: 1 µm (Control and Resv); 2 µm (AS and AS + Resv)