MAFbx and MuRF1 mRNA expression and its relationship with muscular contractility following free muscle transfer / 中华整形外科杂志

<p><b>OBJECTIVE</b>To study muscle atrophy F-box (MAFbx) and muscle ring finger 1 (MuRF1) mRNA expression and its relationship with muscular contraction following free muscle transfer.</p><p><b>METHODS</b>The gracilis muscle was orthotopic transferred in adult rat to establish the animal model. The muscle at the unoperated side was used as control. The expression of MAFbx and MuRF1 mRNA, the muscle contraction and muscle function were measured by real-time PCR and multiple function physiological device. The relationship among the expression of MAFbx and MuRF1 mRNA, the muscle contraction and muscle function was analyzed.</p><p><b>RESULTS</b>After muscle free transfer, muscle wet weight reservation, the maximum contraction and tetanus strength reduce first and increased later, but still lower than those at control side. The expression of MAFbx and MuRF1 mRNA reached peak level 3 - 4 weeks after muscle transfer which was 7.1 and 4.1 times as that at control side. It decreased later, but still higher than that at control side, showing a significant difference between them (P< 0. 05).</p><p><b>CONCLUSIONS</b>Persistent over-expression of MAFbx and MuRF1 mRNA after muscle transfer has a close relationship with muscle atrophy and muscle dysfunction. MAFbx and MuRF1 can be used as markers for early muscle atrophy, and also as potential target for drug treatment of muscle atrophy.</p>

Morphologic observation of the regenerated nerve in reconstructed penis with sensory nerve implantation in rabbit / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate the mechanism of sensory nerve regeneration of the reconstructed penis with sensory nerve implantation and to explore a new surgical technique to improve the postoperative sensory function in phallic reconstruction.</p><p><b>METHODS</b>Adult male New Zealand rabbits were randomly divided into experimental group (n = 20, with sensory nerve implantation) and control group (n = 20, without sensory nerve implantation), which were both performed phalloplasty with a superficial epigastric faciovascular pedicle flap. Postoperatively, the nerve regeneration process of the reconstructed penis was observed histologically.</p><p><b>RESULTS</b>In experimental group, the amount of CGRP positive nerve fibers increased markedly with the time prolonged, whereas merely a few CGRP positive fibers scattered in deep dermis 6 months later in the other group. The cutaneous sensory nerve regeneration of the reconstructed penis in experimental group shows the procedure that the myelinated axon began to exist within 3 months, thereafter the myelinated axon and unmyelinated axon were both observed under the electron microscope.</p><p><b>CONCLUSION</b>These findings show that the rabbit model of phalloplasty with sensory nerve implantation can acquire well sensory reinnervation, and bring a light to clinical application for restoration of sensory function in reconstructed penis.</p>

Anatomy of buccal and marginal mandibular branches of facial nerve and its clinical significance / 中华整形外科杂志

<p><b>OBJECTIVE</b>To study the course and distribution of buccal and marginal mandibular branches of facial nerve, and its relevance to the treatment of facial paralysis and the protection of facial nerve during surgery.</p><p><b>METHODS</b>12 cadaver heads were dissected (24 specimens). The course of the buccal and marginal mandibular branch and the interconnections between them were observed. The relationship of buccal branch to parotid duct, marginal mandibular branch to the inferior border of mandible were studied. With modified Sihler's staining technique, the distribution of facial nerve branches in innervated mimetic muscles was displayed. These anatomic relationships mentioned above were further confirmed during the operation of 40 patients with facial paralysis.</p><p><b>RESULTS</b>Parotid duct had a constant surface landmark. Buccal branch mainly consisted of 2-3 ramifications in 87.5% of the specimens, while marginal mandibular branch was double or single in 95.9% of the specimens. The buccal branch coursed within the distance between 10.7 mm above and 9.3 mm below the parotid duct, and innervated mimetic muscles of midface. The marginal mandibular branch coursed within the distance between 13.4 mm above and 4.8 mm below the lower border of mandible, crossed superiorly the facial artery and innervated mimetic muscles of lower lip.</p><p><b>CONCLUSIONS</b>There is a close relationship of buccal branch to parotid duct and marginal mandibular branch to facial artery and lower border of mandible. With modified Sihler's staining technique, the original 3-dimensional picture of the intramuscular nerve distribution in human mimetic muscles.</p>

Location of somatic sensory neurons of the skin and dorsal nerve of the penis in rabbits / 中华男科学杂志

<p><b>OBJECTIVE</b>To trace the segmental distribution of somatic sensory neurons of the skin and dorsal nerve in the rabbitś penis.</p><p><b>METHODS</b>The experiment was performed on 8 adult male rabbits with the nerve tracing method of retrograde axonal transport of horseradish peroxidase (HRP), which was injected into the dermis around the penis and the dorsal nerve of the penis. The rabbits were sacrificed five days later to harvest the spinal cord segments and the dorsal root ganglia of lumbosacral segments for histological study.</p><p><b>RESULTS</b>The HRP tracing showed that a number of labeled HRP positive neurons appeared in spinal ganglia (S2 - S4) in all the rabbits, and distributed segmentally. The counts of the positive neurons different segments were: S2 (215.0 +/- 10.2) , S3 (242.2 +/- 8.3) and S4 (109.7 +/- 8.4) respectively, with statistically significant difference between the two groups.</p><p><b>CONCLUSION</b>The rabbit's sensory nerve fibers in both the skin and the dorsal nerve of the penis are rooted in the S2-S4 segments of spinal ganglia, which distribute regularly.</p>

Transfection of agrin gene on the recovery of muscle function after free neurovascular muscle transfer / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate the effects of transfection of agrin gene on the recovery of muscle function after a free neurovascular muscle transfer.</p><p><b>METHODS</b>The electrical gene transfection was performed when the gracilis muscle of the SD rat was completed free neurovascular transfer. The experimental group was treated with pCS2+ -agrin, the group with plasmid pCS2+ as the negative control and the group with normal saline as the frank control. The muscle function, expression of neural agrin and the junctional nAChR number was measured after the operation.</p><p><b>RESULTS</b>At 4, 5 and 10 weeks postoperatively, the pCS2+ -agrin group was significantly better than the control groups in muscle function (P < 0.05 ). The immunohistochemical staining showed an increasing deposition of the agrin protein near the endplate at 1 and 5 weeks after the operation, but decreasing remarkably to the level of control groups at 10 weeks postoperatively. The pCS2+ -agrin group was significantly more than the control groups in junctional nAChR number at every points of the time postoperatively.</p><p><b>CONCLUSIONS</b>Transfection of agrin gene in the transferred muscle may increase the early recovery of muscle function.</p>

Changes of acetylcholine receptor distribution at the motor end-plates following muscle transfer / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate the changes of acetylcholine receptor (AChR) distribution at the neuromuscular junction (i.e. motor end-plate) following the free neurovascular muscle transfer.</p><p><b>METHODS</b>AChR in the gracilis muscle of the Wistar rat following free neurovascular transfer were labeled by fluorescent alpha-bungarotoxin and radioiodinated alpha-bungarotoxin. Then confocal microscope and gamma-counting were estimated to ACHR, qualitatively and quantitatively.</p><p><b>RESULTS</b>The junctional AChR numbers decreased to a minimum at the fourth week postoperatively, whereas the extrajunctional receptor numbers increased. From the fifth week postoperatively, the number of junctional AChR's increased. Even at 30 weeks after transfer, the morphology of the neuromuscular junction failed to return to the preoperative style. The number of acetylcholine receptors at the reinnervated neuromuscular junction also remained lower than the control.</p><p><b>CONCLUSION</b>The persistent weakness following free neurovascular muscle transfer may be attributed to these qualitative and quantitative changes at the neuromuscular junction.</p>