## 3 Result and Discussion
### In Vivo Evaluation
#### 3.4.1 Histological Examination  
Histological examinations showed that, in the micrographs of the Blank group (no treatment applied), severe damages in the excised wound sites were detected after 21 days and 30 days, respectively. In the Control group, there was preliminary epithelial tissue growth on the 21 st day. The wound surface was still accompanied by necrotic tissue and thicker scabs. Vasodilation was also clearly visible. No skin receptors or hair follicles were found to grow. There was no complete development on the 30 th day. After epithelialization, necrotic tissue and thickened dermal tissue could still be seen (Figure 8). Recalling the findings of [PERSON] et al., who reported that the 3M\({}^{\text{TM}}\) Cavilon\({}^{\text{TM}}\) no-sting barrier films mainly protect the irradiation site against friction from fabrics and were able to delay the occurrence of pruritus, steroids and other anti-inflammatory drugs should be used for the treatment of hyperemia and damaged tissue [30]. The wound scabs in the EYO group were less than those in the Blank group and the Control group. The growth and re-epithelialization of hair follicle tissue was also observed on the 30 th day. From day 21 to day 30, inflammatory cell infiltration tended to decrease. [PERSON] et al., used EYO to treat burn wounds in rats and observed the growth of collagen fibers and granulation tissue after 14 days of treatment, as well as new collagen fibers and veins on the 21 st day, during which the wounds were nearly re-epithelialized [23]. [PERSON] et al., applied EYO in the treatment of third-degree burns and demonstrated good re-epithelialization effects as well as the absence of scabs or scars on the wound surface [20]. The present study also demonstrated the excellent restorative effects of EYO for radiodermatitis wounds. In the PGC112 group, there was not a large amount of matrix on the surface of the wound. There was very little steep hard skin tissue or surface scabs around the wound. The wound showed complete re-epithelialized tissue, and hair follicles were seen on the 30 th day. The PGC films provided a moist environment for wound repair. As a result, large amounts of matrices were less likely to accumulate on the wound surface, and there were less hardened tissues and scabs around the wound. In addition to the good re-epithelialization of the wounds, follicle growth was noticed on the 30 th day. The films were also able to limit the proliferation of fibroblasts and reduce scarring. The repaired tissue retained its smoothness and elasticity. The antibacterial properties of chitosan have also been applied for treating burn wounds [31]. [PERSON] et al., fabricated a hydrogel from chitosan, gelatin, and honey and obtained excellent area ratios of repaired wounds [32]. [PERSON] et al., used chitosan-gelatin-fibrin composite bandages to treat burn wounds and  
Figure 7: (**a**) Macroscopic images of radiation dermatitis wound in rats; (**b**) Comparison of dermatitis area in each group. Means with different letters were significantly different (\(p\) < 0.05, mean \(\pm\) SD, \(n=5\)). demonstrated that chitosan was able to promote the migration of fibrils and keratinocytes to a wound [33]. Figure 8: Histological analysis of dermatitis wound by H & E staining after 21 days and 30 days. The results of the PGC/0.5 EYO group were similar to those of the PGC112 group. From day 21 to day 30, the infiltration of inflammatory cells was reduced. Collagen fiber deposition, angiogenesis, granulation tissue, and hair follicle formation were observed. The new epithelial tissue covered most of the wound surface, which was a good wound closure effect. The PGC-EYO group had the best wound healing results and the smallest wound area among all the groups, as this dressing offers a moist environment along with the EYO's function of accelerating wound closure. The stained slices showed a decrease in inflammatory cell infiltration and the presence of collagen deposits, as well as the formation of new blood vessels, granulation tissue, and follicles.