Objective To explore the difference in terahertz signal characteristics between rat skin scar and normal skin using terahertz time-domain spectroscopy technology,thereby providing a novel non-invasive detection technique for the pathological examination of skin scars.Methods A rat model of whole-layer skin defect was prepared,and a reflectance terahertz time-domain spectroscopy system was used to obtain the terahertz signal maps of normal skin and scarred area.Results The terahertz signals of normal skin showed two obvious reflection time-domain signal peaks,and the characteristics of the reflection peaks at different reflection points were relatively regular.The terahertz signals of skin scar also had two obvious reflection time-domain signal peaks,but the highest peak was lower than that of normal skin.In addition,principal component analysis revealed that skin scar signals and normal skin signals were clustered together separately.The terahertz signal at different sites differed significantly(P<0.05).Conclusion Terahertz time-domain spectroscopy technology can be applied to the non-invasive detection of skin scarring,exhibiting a good application prospect in biomedicine.

Objective To explore the differences in terahertz(THz)signal characteristics between normal and ischemic liver tissues of New Zealand rabbits using THz time-domain spectroscopy(THz-TDS),thereby providing a novel detection technique for the pathological detection of liver tissues.Methods Liver ischemia models were established in New Zealand rabbits.The THz scanning signal maps of normal and ischemic liver tissues were obtained using a reflective THz-TDS system,and the acquired signals were subjected to principal component analysis.Results Both normal and ischemic liver tissues displayed two distinct peaks in their THz signals.However,the amplitude of the THz signal in ischemic liver tissue was higher than that in normal liver tissue,with significant differences also observed in their signal morphologies.Principal component analysis results revealed a clear clustered distribution between the signals of normal and ischemic liver tissues,indicating that THz-TDS could effectively distinguish between the two tissue types.Conclusion THz-TDS can be applied to the detection of ischemic liver tissue,providing experimental evidence to support further research on the early diagnosis of liver ischemia and exhibiting broad prospects for clinical application.

Objective To explore the difference in terahertz signal characteristics between rat skin scar and normal skin using terahertz time-domain spectroscopy technology,thereby providing a novel non-invasive detection technique for the pathological examination of skin scars.Methods A rat model of whole-layer skin defect was prepared,and a reflectance terahertz time-domain spectroscopy system was used to obtain the terahertz signal maps of normal skin and scarred area.Results The terahertz signals of normal skin showed two obvious reflection time-domain signal peaks,and the characteristics of the reflection peaks at different reflection points were relatively regular.The terahertz signals of skin scar also had two obvious reflection time-domain signal peaks,but the highest peak was lower than that of normal skin.In addition,principal component analysis revealed that skin scar signals and normal skin signals were clustered together separately.The terahertz signal at different sites differed significantly(P<0.05).Conclusion Terahertz time-domain spectroscopy technology can be applied to the non-invasive detection of skin scarring,exhibiting a good application prospect in biomedicine.

Objective To explore the differences in terahertz(THz)signal characteristics between normal and ischemic liver tissues of New Zealand rabbits using THz time-domain spectroscopy(THz-TDS),thereby providing a novel detection technique for the pathological detection of liver tissues.Methods Liver ischemia models were established in New Zealand rabbits.The THz scanning signal maps of normal and ischemic liver tissues were obtained using a reflective THz-TDS system,and the acquired signals were subjected to principal component analysis.Results Both normal and ischemic liver tissues displayed two distinct peaks in their THz signals.However,the amplitude of the THz signal in ischemic liver tissue was higher than that in normal liver tissue,with significant differences also observed in their signal morphologies.Principal component analysis results revealed a clear clustered distribution between the signals of normal and ischemic liver tissues,indicating that THz-TDS could effectively distinguish between the two tissue types.Conclusion THz-TDS can be applied to the detection of ischemic liver tissue,providing experimental evidence to support further research on the early diagnosis of liver ischemia and exhibiting broad prospects for clinical application.

BACKGROUND:Minipigs are often used in research fields such as skin injury,vascular trauma and cosmetic medicine because they are highly similar to human beings in terms of skin tissue structure and cardiovascular system.Hydrogel as a wound repair drug possesses a variety of excellent physicochemical properties such as strong water retention and adhesion,which can provide isolation moisturization and drug release for wounds. OBJECTIVE:To summarize and conclude the progress of the application of trauma models for different experimental purposes of hydrogel therapy for minipigs,to reveal the development status of various types of minipig trauma models,to analyze the deficiencies of minipig trauma models at the present stage. METHODS:The relevant articles published in Web of Science database and CNKI database from the establishment of each database to 2023 were checked,using"piglet,miniature pig,minipig,miniature pig;gel,hydrogel;trauma,injury,wound,lesion,incision"as Chinese search terms and"Miniature Swine,Miniature pig,minipig;gel,hydrogel;injury,wound,lesion,incision"as English search terms.A total of 438 Chinese and English documents were retrieved,and 59 documents were included in the study through the inclusion and exclusion criteria. RESULTS AND CONCLUSION:(1)At present,the main models used clinically for trauma repair are large animal species(dogs and pigs),rabbits,and rodents(rats and mice).Because the skin structure of the minipig is more like that of humans,the minipig is the most ideal animal model for trauma repair.(2)In the in-vitro skin injury model,skin defect model is the basic wound model,which can be divided into full skin defect model and medium-thickness skin defect model according to the depth of the wound defect.Burn wound model and infected wound model are multidimensional models with hot metal scald and bacterial culture imposed on the basis of the skin defect model,which have the advantages of high safety coefficient and low operation difficulty.(3)In the in-vivo trauma repair model,mini-pigs are used as esophageal cricothyrotomy model which is more in line with the pathological state of clinical diseases.Mini-pigs are used in the gastric perforation and vascular hemostasis model,which can visually demonstrate the stronger organ adhesion,hemostatic properties and tissue regeneration-promoting effects of the hydrogel.(4)The specific parts of the pig also has the corresponding mode of use:pig ear is usually used to evaluate the hydrogel drug delayed-release effect.Porcine cellular proteins and pig skin collagen are mostly used to prepare composite hydrogels of tissue origin.