Immunofluorescence laser confocal expression and localization study of rat nerve growth guidance cues Netrin-1 and Slit2 after spinal cord injury / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To observe the expression and distribution of adult rat axon guidance cues Netrin-1 and Slit2 at different time points after spinal cord injury and to investigate the guidance mechanism of regenerated axons.</p><p><b>METHODS</b>Twenty adult Sprague Dawley (SD) rats were divided randomly into five groups with 4 in each. Four groups of them were used to make Allen's spinal cord punch models and we took materials randomly from one of them on the 2nd, 4th, 7th and 14th day respectively after operation. The left one group was taken as the control group. Immunofluorescence laser confocal scan was used to examine the co-expression and localization of Netrin-1 and Slit2 proteins in the injured site of the spinal cord.</p><p><b>RESULTS</b>Within two weeks after SCI, the expression of Netrin-1 and Slit2 proteins increased temporarily and there was co-expression of them on the neuron plasma membrane.</p><p><b>CONCLUSIONS</b>Synchronous high expression and co-expression of axon attractant Netrin-1 and repellent Slit2 are found in the adult rat injured spinal cord in the damaged local and vicinity parts, and probably, they act as the key regulators of axon guidance regeneration.</p>

Reconstruction of finger pulp defect with reversed fasciocutaneous island flap from same finger / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the clinical curative effect of reconstruction of finger pulp defect by anastomosis of reversed fasciocutaneous island flap with dorsal branch of the digital nerve of the same finger.</p><p><b>METHODS</b>The restoration of finger pulp defect with fasciocutaneous island flap from the same finger was conducted in 25 cases (30 fingers) from January 2002 to June 2003. Nine patients (11 fingers) whose flaps with dorsal branch of the digital nerve anastomosed with the digital inherent nerve around the surface of the wound were Group A and the others were Group B. The follow-up was carried out at 3 and 9 months after the operation to observe the shape of finger pulp and the sense restoration between two groups.</p><p><b>RESULTS</b>All flaps of 25 cases (30 fingers) survived. Three months after operation, the patients had fully grown finger pulps and recovered the superficial sensation and tactile sense of finger pulps. The two point discrimination on average was 5.00 mm+/-0.23 mm in Group A and 6.00 mm+/-0.30 mm in Group B. The difference between two groups was highly significant. Nine months later, their senses of finger pulps between two groups were recovered basically.</p><p><b>CONCLUSIONS</b>The reversed fasciocutaneous island flap from the same finger is the first choice to reconstruct the finger pulp defect, and the anastomosis of dorsal branch of the digital nerve shall be determined according to the specific condition.</p>