Establishment of skin scald model in mice / 法医学杂志

OBJECTIVE@#To establish the model of skin scald in mice for the study of skin thermal injuries.@*METHODS@#After anaesthetization mice were scalded in a 1 cm-diameter circle area on the central dorsum by boiling water at contact times: 10s or 25s. The mice were sacrificed at 1, 3, 5, 7 and 10 days after scald. The skin samples were collected and analyzed by gross and histopathological examinations.@*RESULTS@#Deep II degree thermal injury involving full-thickness skin was observed in the 10s scald group. III degree thermal injury involving full-thickness skin and the dorsal skeletal muscle was observed in the 25 s scald group.@*CONCLUSION@#A mouse skin scald model is established which is stable and can be used on the skin thermal injury in future research.

The number of circulating fibrocytes of skeletal muscle in rats after contusion / 法医学杂志

OBJECTION@#To investigate the time-dependent appearance of circulating fibrocytes of skeletal muscle in rats after contusion.@*METHODS@#The model of skeletal muscle wound was established in rat. The circulating fibrocytes in contused skeletal muscle were detected by CD45 and procollagen I double immunofluorescence staining method.@*RESULTS@#In the control group, CD45- and procollagen I-positive cells were not detected in skeletal muscle. A few CD45 cells were observed aged from 6 h to 1 d after contusion. A few CD45- and procollagen I-positive cells (fibrocytes) initially gathered in injury area 3d after injury. The ratio of positive fibrocytes significantly increased 5 d after injury. The ratio of fibrocytes was highest at 7 d after contusion and then decreased. The volume of fibrocytes showed bigger with injury time increase compared with 3 d group. The expression of procollagen I and CD45 were weakened at 14d after injury.@*CONCLUSION@#The circulating fibrocytes are detected in contused skeletal muscle in time-dependent pattern. Circulating fibrocytes may be a marker in the wound age determination for contused skeletal muscle.

Nifedipine attenuates vascular inflammation via inhibin NF-κB activity / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore the effects and related mechanism of nifedipine on vascular inflammation induced by cuff placement.</p><p><b>METHODS</b>Adult male C57BL/6J mice (10 to 12 weeks of age) were assigned to control (no cuff placement without nifedipine), cuff placement (cuff placement without nifedipine) and treatment (cuff placement with nifedipine 1 or 5 mg×kg(-1)×d(-1)) groups. Activity of NF-κB in injured artery was measured 5 days after operation. MCP-1 expression and nuclear translocation of NF-κB were examined in injured artery 7 days after operation.</p><p><b>RESULTS</b>DNA-binding activity of NF-κB was significantly increased in the injured artery 5 days after cuff placement which could be downregulated by nifedipine 5 mg×kg(-1)×d(-1). MCP-1 mRNA expression in the injured arteries was increased 7 days after cuff placement and which could be significantly attenuated by nifedipine 5 mg×kg(-1)×d(-1). Cuff placement decreased the cytoplasmic level of p50, IκBα, IκBβ, and increased the nuclear level of p50. Nifedipine 5 mg×kg(-1)×d(-1) significantly attenuated these changes.</p><p><b>CONCLUSION</b>Our results suggest that high dose nifedipine could suppresses expression of MCP-1 induced by injured arteries via the inhibin NF-κB DNA binding activity, thereby attenuating vascular inflammation.</p>