Protective Effects of Modeled Superoxide Dismutase Coordination Compound (MSODa) Against Ischemia/Reperfusion Injury in Rat Skeletal Muscle.

BACKGROUND/AIM: Ischemia/reperfusion (I/R) injury of skeletal muscles is common pathophysiology during surgeries and the superoxide dismutase (SOD) plays a critical role in this process. SOD-modeled coordination compound (MSODa) may simulate the protective effects as SOD. METHODS: Therefore, this study was designed to explore the protective effects and underlying mechanism of MSODa on malondialdehyde (MDA) and integrin-ß2 (CD11b/CD18) in plasma, myeloperoxidase (MPO) and intercellular cell adhesion molecule-1 (ICAM-1) in tissue, and morphological changes before and after I/R injury. The rat model of I/R in hind limb was established and randomly divided into sham, ischemia, I/R, I/R-treated with saline, SOD, and MSODa, respectively. RESULTS: These results showed that averaged values for MDA, MPO, CD11b/CD18, and ICAM-1 were significantly increased (P < 0.01 vs ischemia alone) in a time-dependent fashion along with marked tissue remodeling, such as abnormal arrangement of muscular fibers, interstitial edema, vasodilation with no-reflow, inflammatory cells adherent and infiltration, structural changes in mitochondrial, and decrease in glycogens as well. However, all parameter changes induced by I/R injury were reversed, at least partially, by MSODa and SOD treatments and intriguingly, the beneficial/protective effects of MSODa was superior to SOD with an early onset. CONCLUSION: This novel finding demonstrates that MSODa improves I/R injury of skeletal muscles due at least partially to inhibition of adherent molecule expression and reduction of oxygen free radical formation during I/R pathophysiological processes and this protective action of MSODa was superior to SOD, highlighting the bright future for MSODa in clinical management of tissue I/R injury.

Rare massive osteolipoma in the upper part of the knee in a young adult.

Lipoma is a common benign soft tissue tumor. This article describes a massive osteolipoma, an unusual lipoma that is fixed to the femoral periosteum. A 21-year-old man presented with a subcutaneous mass at the knee region, which had been present for more than 36 months, and a slight limitation of joint flexibility. On physical examination, a mass approximately 12×6×2 cm(3) in dimension was palpable beneath the skin at the knee proximal medial area when the knee was in flexion. The mass was ovoid, hard, nontender, well demarcated, large, subcutaneous, and relatively fixed to the femur. Medical imaging examination showed that the femur had a well-demarcated mass with a basement. No prominent body weight loss was noted. The excisional mass of 16×12×10 cm(3) was not well encapsulated by a thin, fibrous membrane and had an apparently osseous basal portion. Intraoperative rapid frozen section revealed that the tumor was derived from the adipose cells. The postoperative course was uneventful. The definitive pathologic diagnosis was intermuscular osteolipoma without evidence of malignancy. No recurrence was observed at 6-month follow-up. Osteolipoma with independent bone and an osseous basal portion is rare, especially in young adults. Osteolipoma has the same prognosis as simple lipoma, and surgical excision is the recommended treatment. To the authors' knowledge, such a massive osteolipoma has not been reported.

[The fate of donor bone cells in different diameter bone grafts: an experiment study].

OBJECTIVE: To investigate the fate of donor bone cells in bone grafts of different diameters during repairing bone defects. METHODS: One hundred sixteen female syngeneic inbred DA rats were established as radial defect model of 3 kinds: structural bone grafting group (n = 56), morselized bone grafting group (n = 56), and blank group (without bone grafting, n = 4), to be used as receptors The ilia of 58 male inbred DA rats, as donors, were harvested and made into structural bone grafts 2 mm in diameter and morselized bone grafts 0.3 - 0.5 mm in diameter to be transplanted into the radial defects of the female receptors. One and four days, and 1, 2, 4, 6, and 8 weeks after transplantation DNA was extracted from the grafted bones and polymerase chain reaction (PCR) specific for the sex-determining region of Y-chromosome (Sry) was performed to observe the presence and relative amount of Y-chromosome originating from the bone grafts, expression of the sex-determining gene Sry in the receptors' bones and the histology of the receptors' bones. RESULTS: In structural bone grafting group, the amounts of Sry-specific bands decreased in the early time and disappeared 1 week after transplantation, and re-appeared 4 weeks after transplantation with the amount increasing with the lapse of time. In morselized bone grafting group, Sry-specific bands were detected all the time but their amounts decreased with the lapse of time. At each time point, morselized bone graft provided more living osteocytes with better effect of osteogenesis in comparison with the structural bone graft. CONCLUSION: Bone grafts of different diameters provide donor cells in repairing bone defects. Having more surviving osteocytes, morselized bone grafts may accelerate the healing pf bone defects, thus providing a new and effective method to repair bone defects and spinal fusion clinically.