Objective:To explore differences in the radiation-induced intestinal injury in mice exposed to ultra-high dose rate (FLASH) and conventional-dose-rate (CONV) pulsed X-ray irradiation in order to provide evidence for the application of ultra-high dose rate pulsed X-rays in gastrointestinal radiotherapy.Methods:Using the random number table method, 32 C57BL/6J mice were randomly divided into four groups: a sham irradiation group (SHAM), two conventional dose rate groups (CONV0.067 and CONV0.1), and an ultra-high dose rate group (F215), with each group containing eight mice. All groups, except SHAM, received a single 12 Gy abdominal X-ray irradiation at dose rates of 0.067, 0.1, and 215 Gy/s, respectively. At 3 d post-irradiation, histopathological (hematoxylin-eosin staining, HE staining), immunohistochemical, and Western blot analysis were performed to assess the histopathological markers and oxidative stress indicators of intestinal tissues, as well as relevant proteins involved in signaling pathways.Results:At 3 d post-irradiation, mice in all irradiation groups suffered from varying degrees of intestinal tissue degeneration and necrosis, epithelial cell shedding, villus shortening, and crypt loss ( t = 5.75, 8.79, 5.71, P < 0.05). Regarding oxidative stress, at 3 d post-irradiation, mice in the CONV0.067 and CONV0.1 groups showed significantly lower levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX), glutathione (GSH), and total antioxidant capacity (T-AOC) compared to those in the F215 group ( t = 7.06-10.64, P < 0.01). In contrast, their malondialdehyde (MDA) levels were significantly elevated ( t = 11.06, 8.31, P < 0.01), with no statistical significance observed between them and mice in the F215 group ( P > 0.05). Immunohistochemical and Western blot analyses indicated that at 3 d post-irradiation, mice in the three irradiation groups exhibited an upward trend in the Nrf2 and HO-1 protein levels and a downward trend in the Keap1 protein level compared to those in the SHAM group. Notably, statistical significance was observed between the F215 group and the two conventional dose rate groups ( t = 4.89-20.95, P < 0.05). These result were consistent with the prior changes in antioxidant markers. Conclusions:Ultra-high-dose-rate X-ray irradiation reduces acute RIII by alleviating oxidative stress and modulating the expression of the Keap1-Nrf2-HO-1 signaling pathway.

Objective:To explore differences in the radiation-induced intestinal injury in mice exposed to ultra-high dose rate (FLASH) and conventional-dose-rate (CONV) pulsed X-ray irradiation in order to provide evidence for the application of ultra-high dose rate pulsed X-rays in gastrointestinal radiotherapy.Methods:Using the random number table method, 32 C57BL/6J mice were randomly divided into four groups: a sham irradiation group (SHAM), two conventional dose rate groups (CONV0.067 and CONV0.1), and an ultra-high dose rate group (F215), with each group containing eight mice. All groups, except SHAM, received a single 12 Gy abdominal X-ray irradiation at dose rates of 0.067, 0.1, and 215 Gy/s, respectively. At 3 d post-irradiation, histopathological (hematoxylin-eosin staining, HE staining), immunohistochemical, and Western blot analysis were performed to assess the histopathological markers and oxidative stress indicators of intestinal tissues, as well as relevant proteins involved in signaling pathways.Results:At 3 d post-irradiation, mice in all irradiation groups suffered from varying degrees of intestinal tissue degeneration and necrosis, epithelial cell shedding, villus shortening, and crypt loss ( t = 5.75, 8.79, 5.71, P < 0.05). Regarding oxidative stress, at 3 d post-irradiation, mice in the CONV0.067 and CONV0.1 groups showed significantly lower levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX), glutathione (GSH), and total antioxidant capacity (T-AOC) compared to those in the F215 group ( t = 7.06-10.64, P < 0.01). In contrast, their malondialdehyde (MDA) levels were significantly elevated ( t = 11.06, 8.31, P < 0.01), with no statistical significance observed between them and mice in the F215 group ( P > 0.05). Immunohistochemical and Western blot analyses indicated that at 3 d post-irradiation, mice in the three irradiation groups exhibited an upward trend in the Nrf2 and HO-1 protein levels and a downward trend in the Keap1 protein level compared to those in the SHAM group. Notably, statistical significance was observed between the F215 group and the two conventional dose rate groups ( t = 4.89-20.95, P < 0.05). These result were consistent with the prior changes in antioxidant markers. Conclusions:Ultra-high-dose-rate X-ray irradiation reduces acute RIII by alleviating oxidative stress and modulating the expression of the Keap1-Nrf2-HO-1 signaling pathway.

Traditional Chinese medicine,ancient Greek medicine,Ayurvedic medicine,and Arab medicine are recognized as the four major traditional medicines in the world.It reviews the education and training systems of the four major traditional medicines and finds that traditional Chinese medicine focuses on the teacher-student relation-ship and the combination of theory and practice;Ancient Greek medicine was mainly characterized by strong theoreti-cal research and experimental observation;Ayurveda highly values cultural identity as its main characteristic;Arab medicine attaches great importance to cultural exchange and practical promotion.It suggests promoting innovative de-velopment,strengthening practical teaching,improving teaching quality,strengthening international exchanges and cooperation,and increasing public acceptance abroad.

Traditional Chinese medicine,ancient Greek medicine,Ayurvedic medicine,and Arab medicine are recognized as the four major traditional medicines in the world.It reviews the education and training systems of the four major traditional medicines and finds that traditional Chinese medicine focuses on the teacher-student relation-ship and the combination of theory and practice;Ancient Greek medicine was mainly characterized by strong theoreti-cal research and experimental observation;Ayurveda highly values cultural identity as its main characteristic;Arab medicine attaches great importance to cultural exchange and practical promotion.It suggests promoting innovative de-velopment,strengthening practical teaching,improving teaching quality,strengthening international exchanges and cooperation,and increasing public acceptance abroad.

Traditional Chinese medicine,ancient Greek medicine,Ayurvedic medicine,and Arab medicine are recognized as the four major traditional medicines in the world.It reviews the education and training systems of the four major traditional medicines and finds that traditional Chinese medicine focuses on the teacher-student relation-ship and the combination of theory and practice;Ancient Greek medicine was mainly characterized by strong theoreti-cal research and experimental observation;Ayurveda highly values cultural identity as its main characteristic;Arab medicine attaches great importance to cultural exchange and practical promotion.It suggests promoting innovative de-velopment,strengthening practical teaching,improving teaching quality,strengthening international exchanges and cooperation,and increasing public acceptance abroad.

Traditional Chinese medicine,ancient Greek medicine,Ayurvedic medicine,and Arab medicine are recognized as the four major traditional medicines in the world.It reviews the education and training systems of the four major traditional medicines and finds that traditional Chinese medicine focuses on the teacher-student relation-ship and the combination of theory and practice;Ancient Greek medicine was mainly characterized by strong theoreti-cal research and experimental observation;Ayurveda highly values cultural identity as its main characteristic;Arab medicine attaches great importance to cultural exchange and practical promotion.It suggests promoting innovative de-velopment,strengthening practical teaching,improving teaching quality,strengthening international exchanges and cooperation,and increasing public acceptance abroad.

Traditional Chinese medicine,ancient Greek medicine,Ayurvedic medicine,and Arab medicine are recognized as the four major traditional medicines in the world.It reviews the education and training systems of the four major traditional medicines and finds that traditional Chinese medicine focuses on the teacher-student relation-ship and the combination of theory and practice;Ancient Greek medicine was mainly characterized by strong theoreti-cal research and experimental observation;Ayurveda highly values cultural identity as its main characteristic;Arab medicine attaches great importance to cultural exchange and practical promotion.It suggests promoting innovative de-velopment,strengthening practical teaching,improving teaching quality,strengthening international exchanges and cooperation,and increasing public acceptance abroad.

Traditional Chinese medicine,ancient Greek medicine,Ayurvedic medicine,and Arab medicine are recognized as the four major traditional medicines in the world.It reviews the education and training systems of the four major traditional medicines and finds that traditional Chinese medicine focuses on the teacher-student relation-ship and the combination of theory and practice;Ancient Greek medicine was mainly characterized by strong theoreti-cal research and experimental observation;Ayurveda highly values cultural identity as its main characteristic;Arab medicine attaches great importance to cultural exchange and practical promotion.It suggests promoting innovative de-velopment,strengthening practical teaching,improving teaching quality,strengthening international exchanges and cooperation,and increasing public acceptance abroad.

Traditional Chinese medicine,ancient Greek medicine,Ayurvedic medicine,and Arab medicine are recognized as the four major traditional medicines in the world.It reviews the education and training systems of the four major traditional medicines and finds that traditional Chinese medicine focuses on the teacher-student relation-ship and the combination of theory and practice;Ancient Greek medicine was mainly characterized by strong theoreti-cal research and experimental observation;Ayurveda highly values cultural identity as its main characteristic;Arab medicine attaches great importance to cultural exchange and practical promotion.It suggests promoting innovative de-velopment,strengthening practical teaching,improving teaching quality,strengthening international exchanges and cooperation,and increasing public acceptance abroad.

Traditional Chinese medicine,ancient Greek medicine,Ayurvedic medicine,and Arab medicine are recognized as the four major traditional medicines in the world.It reviews the education and training systems of the four major traditional medicines and finds that traditional Chinese medicine focuses on the teacher-student relation-ship and the combination of theory and practice;Ancient Greek medicine was mainly characterized by strong theoreti-cal research and experimental observation;Ayurveda highly values cultural identity as its main characteristic;Arab medicine attaches great importance to cultural exchange and practical promotion.It suggests promoting innovative de-velopment,strengthening practical teaching,improving teaching quality,strengthening international exchanges and cooperation,and increasing public acceptance abroad.