AIM： To evaluate the effect of propolis administration on the healing of colon anastomosis with light and transmission electron microscopes. METHODS： Forty-eight Wistar-AIbino female rats were divided into two group...AIM： To evaluate the effect of propolis administration on the healing of colon anastomosis with light and transmission electron microscopes. METHODS： Forty-eight Wistar-AIbino female rats were divided into two groups and had colon resection and anastomosis. In group Ⅰ, rats were fed with standard rat chow pre- and postoperatively. The rats in group Ⅱ were fed with standard rat chow and began receiving oral supplementation of propolis 100 mg/kg per day beginning 7 d before the operation and continued until they were sacrificed. Rats were sacrificed 1, 3, 7 and 14 d after operation, and anastomotic bursting pressures measured. After the resection of anastomotic segments, histopathological examination was performed with light and transmission electron microscopes by two blinded histologists and photographed. RESULTS： The colonic bursting pressures of the propolis group were statistically significantly better than the control group. UItrastructural histopathological analysis of the colon anastomosis revealed that propotis accelerated the phases of the healing process and stimulated mature granulation tissue formation and collagen synthesis of fibroblasts. CONCLUSION： Bursting pressure measurements and ultra structural histopathological evaluation showed that administration of propolis accelerated the healing of colon anastomosis following surgical excision.展开更多
Recently, chitosan nanoparticles have been an attractive biomaterial for their unique properties. Chitosan nanoparticles are mainly used as drug delivers. However, they are seldom used in wound healing after severe bl...Recently, chitosan nanoparticles have been an attractive biomaterial for their unique properties. Chitosan nanoparticles are mainly used as drug delivers. However, they are seldom used in wound healing after severe bleeding. In the present paper, chitosan nanoparticles with an average size of 60.2 nm were prepared through ionic gelation and characterized by X-ray diffraction and FT-infrared spectrometry. A new animal model of severe bleeding was made to evaluate its effects on wound healing besides hemostasis. The results showed that it can achieve well hemostatic effects and also induce wound healing after severe bleeding. Blood cells can be absorbed by chitosan nanoparticles and the bleeding is treated. Furthermore, the chitosan nanoparticles sustains longer than other materials in wound healing. At the 15th day after operation, the chitosan nanoparticles with the size of 58.3 nm can still be seen in the new-regenerated hepatic tissue. It can induce the formation of a clear granulation around the wound site. Through histological observation, we find out that chitosan-TPP nanoparticles can induce wound healing through migration of the inflammatory cells and synthesis of collagen. So, chitosan nanoparticles show us both hemostasis and the ability of wound healing for parenchymal organs.展开更多
Objective：Radiation is an important cause of delayed wound healing,and there still exist many questions regarding the patterns and mechanisms of wound healing.This study investigated the characteristics of wound heal...Objective：Radiation is an important cause of delayed wound healing,and there still exist many questions regarding the patterns and mechanisms of wound healing.This study investigated the characteristics of wound healing after varying doses of local radiation and explored possible causes of the delay in healing caused by radiation.Methods：A full-thickness dorsal longitudinal skin tissue,2 cm in diameter,was excised after local irradiation on one side of the back of swine,and the other side was wounded as a control.The size of the wound area was recorded every two days after injury.Pathological changes,proliferating cell nuclear antigen（PCNA,immunohistochemistry）and apoptosis levels（TUNEL assay）were measured at different time points after wounding.Results：The course of wound healing can be divided into four phases,namely：the arresting phase,the healing priming phase,the fast healing phase,and the healed phase.Although the total wound healing time was closely correlated to the dose of irradiation（R2=0.9758）,it was more dependent on the length of the arresting phase（R2=0.9903）because once the arresting phase ended,the wound healed at a similar speed regardless of radiation doses.Pathological analysis showed that compared with the control side there were more necrotic tissues,slower epithelial crawling,as well as fewer blood vessels and cellular components in the irradiated side at the arresting phase,while other phases revealed no significant difference concerning these measurements.Immunohistochemistry showed that the irradiated wounds had significantly less PCNA-positive and more TUNEL-positive labeling of cells in the arresting phase than in other phases.Moreover,the changes were positively related to the radiation doses,but there was no obvious difference in cell proliferation or apoptosis among the healing priming phase,fast healing phase or healed phase,whether on the control side or on the irradiated side.Conclusions：After local irradiation,the length of the arresting phase determines the wound healing time.Increased apoptosis and decreased cell proliferation might be an important reason for the formation of the arresting phase.展开更多
文摘AIM： To evaluate the effect of propolis administration on the healing of colon anastomosis with light and transmission electron microscopes. METHODS： Forty-eight Wistar-AIbino female rats were divided into two groups and had colon resection and anastomosis. In group Ⅰ, rats were fed with standard rat chow pre- and postoperatively. The rats in group Ⅱ were fed with standard rat chow and began receiving oral supplementation of propolis 100 mg/kg per day beginning 7 d before the operation and continued until they were sacrificed. Rats were sacrificed 1, 3, 7 and 14 d after operation, and anastomotic bursting pressures measured. After the resection of anastomotic segments, histopathological examination was performed with light and transmission electron microscopes by two blinded histologists and photographed. RESULTS： The colonic bursting pressures of the propolis group were statistically significantly better than the control group. UItrastructural histopathological analysis of the colon anastomosis revealed that propotis accelerated the phases of the healing process and stimulated mature granulation tissue formation and collagen synthesis of fibroblasts. CONCLUSION： Bursting pressure measurements and ultra structural histopathological evaluation showed that administration of propolis accelerated the healing of colon anastomosis following surgical excision.
文摘Recently, chitosan nanoparticles have been an attractive biomaterial for their unique properties. Chitosan nanoparticles are mainly used as drug delivers. However, they are seldom used in wound healing after severe bleeding. In the present paper, chitosan nanoparticles with an average size of 60.2 nm were prepared through ionic gelation and characterized by X-ray diffraction and FT-infrared spectrometry. A new animal model of severe bleeding was made to evaluate its effects on wound healing besides hemostasis. The results showed that it can achieve well hemostatic effects and also induce wound healing after severe bleeding. Blood cells can be absorbed by chitosan nanoparticles and the bleeding is treated. Furthermore, the chitosan nanoparticles sustains longer than other materials in wound healing. At the 15th day after operation, the chitosan nanoparticles with the size of 58.3 nm can still be seen in the new-regenerated hepatic tissue. It can induce the formation of a clear granulation around the wound site. Through histological observation, we find out that chitosan-TPP nanoparticles can induce wound healing through migration of the inflammatory cells and synthesis of collagen. So, chitosan nanoparticles show us both hemostasis and the ability of wound healing for parenchymal organs.
文摘Objective：Radiation is an important cause of delayed wound healing,and there still exist many questions regarding the patterns and mechanisms of wound healing.This study investigated the characteristics of wound healing after varying doses of local radiation and explored possible causes of the delay in healing caused by radiation.Methods：A full-thickness dorsal longitudinal skin tissue,2 cm in diameter,was excised after local irradiation on one side of the back of swine,and the other side was wounded as a control.The size of the wound area was recorded every two days after injury.Pathological changes,proliferating cell nuclear antigen（PCNA,immunohistochemistry）and apoptosis levels（TUNEL assay）were measured at different time points after wounding.Results：The course of wound healing can be divided into four phases,namely：the arresting phase,the healing priming phase,the fast healing phase,and the healed phase.Although the total wound healing time was closely correlated to the dose of irradiation（R2=0.9758）,it was more dependent on the length of the arresting phase（R2=0.9903）because once the arresting phase ended,the wound healed at a similar speed regardless of radiation doses.Pathological analysis showed that compared with the control side there were more necrotic tissues,slower epithelial crawling,as well as fewer blood vessels and cellular components in the irradiated side at the arresting phase,while other phases revealed no significant difference concerning these measurements.Immunohistochemistry showed that the irradiated wounds had significantly less PCNA-positive and more TUNEL-positive labeling of cells in the arresting phase than in other phases.Moreover,the changes were positively related to the radiation doses,but there was no obvious difference in cell proliferation or apoptosis among the healing priming phase,fast healing phase or healed phase,whether on the control side or on the irradiated side.Conclusions：After local irradiation,the length of the arresting phase determines the wound healing time.Increased apoptosis and decreased cell proliferation might be an important reason for the formation of the arresting phase.
