Osteoinduction Using Recombinant Bone Morphogenetic Protein-7 Gene / 대한정형외과학회잡지

PURPOSE: The aim of this study was to develop recombinant human Bone Morphogenetic Protein-7 (BMP7)-stable cells and recombinant human BMP7 adenoviruses (AdBMP7) for osteoinduction and osteoregeneration in musculoskeletal diseases. MATERIALS AND METHODS: The human BMP7 cDNA was amplified from a human osteosarcoma cell line, U2OS using a reverse transcription-polymerase chain reaction and cloned into a eukaryotic expression vector. The BMP7-stable HEK293 cells (HEK293/BMP7) were prepared by transfecting the recombinant BMP7 plasmid vector. The recombinant human BMP7 adenovirus (AdBMP7) was constructed using the AdEasy vector system. The BMP7 expression levels in HEK293/BMP7 and AdBMP7 were measured by activity staining for alkaline phosphatase in mouse C2C12 promyoblast cells. The BMP7-stable HEK293 cells, AdBMP7 itself, or AdBMP7-transduced human fibroblasts were injected into the subcutaneous tissues and the calf muscles of immunocompromised mice. The amount of ectopic bone formation was evaluated by radiographic and histological analyses. RESULTS: Ectopic bone formation was observed after injecting the BMP7-stable HEK293 cells with either the AdBMP7 itself or AdBMP7-transduced human fibroblasts into the subcutaneous tissues and calf muscles of immunocompromised mice. CONCLUSION: These results showed that HEK293/BMP7 cells and AdBMP7 have a significant potential for bone formation and the regeneration of various bone diseases.

Differential Expression of Somatostatin Receptor Subtype 2 in Dorsal Root Ganglia after Ischemic Injury in the Rat / 대한정형외과학회잡지

PURPOSE: The somatostatin has been suggested to play a role in the transmission of neurotransmitters and the modulation of pain. Therefore, this study was carried out to investigate the spatial and temporal alterations of sstr2 (somatostatin receptors 2) immunoreactivity after an ischemic injury in rats. MATERIALS AND METHODS: Fifty-five rats (Sprague-Dawley, 200-250 g) were assigned to the experimental group, the other five to the control group. In the experimental group, an occlusion of the left common iliac artery was made using an aneurysm clip. Ten groups were classified according to the time after ischemiareperfusion. Dorsal root ganglia (DRG) cells in the L4, L5, L6 levels of the spinal cord, from the rats were examined the sstr2 using an immunohistochemistry technique. RESULTS: The sstr2A/B immunoreactivity (IR) appeared in the DRG after ischemia-reperfusion. The number of sstr2A- and sstr2B-IR neurons were markedly lower in the group of rats 12 hours after ischemia-reperfusion. In the group of rats one day after ischemia-reperfusion, the sstr2A- and sstr2B-IR neurons began to recover in both number and immunoreactivity. Furthermore, 3 days after ischemia-reperfusion, sstr2A/B immunoreactivity decreased in number and immunoreactivity, and 7 days after ischemia-reperfusion, very weak immunoreactivity was observed in the cytoplasm. CONCLUSION: The sstr2A/B immunoreactivity of the DRG exhibited different appearance according to the post-traumatic compartment syndrome or ischemic injury of the leg. In addition, the chronological alterations of sstr2A and sstr2B immunoreactivities may be important in controlling the pain after a transient ischemia-reperfusion event.

An Assessment of the Mechanical Properties of Long Bone Fractures Using an Impulse Response Method / 대한정형외과학회잡지

PURPOSE: To establish the basis for a non-invasive and non-destructive assessment of the mechanical properties during natural fracture healing by analyzing the vibrational property of the fracture healing and comparing the vibrational property, the bone healing status (as determined by X-ray) and the mechanical strength parameters. MATERIALS AND METHODS: The tibial shafts of rabbits were broken under general anesthesia. The rabbits were sacrificed at 2, 4, 6 weeks after the fracture, then X-rays of the fractured tibias were sequentially taken to detect the fracture healing. The vibration mode and the biomechanical strength were measured. RESULTS: According to the results of a multiple regression analysis, the standardized coefficients of callus, apposition, lateral angulation, DAMP1, FREQ1 in the fractured tibias, were -0.80, -0.23, -0.21, -0.25, -0.25. In normal contralateral tibias, the standardized coefficients of the area, FREQ1, DAMP1, FREQ2, DAMP3 were -0.73, 0.28, 0.41, 0.39, -0.25. CONCLUSION: A monitoring of the fracture healing process that utilizes the frequency response function is thought to be useful in detecting the early phase of healing within 4 weeks. Additional studies on the vibrational characteristics of the healing bones after a clinical union or after simillar pathologies should be pursued so that future diagnostic applications ca be made.

A CASE OF SERO-MUCOUS CYSTADENOMA OF THE PAROTID GLAND

Cystadenomas are benign neoplasm in which the epithelium demonstrates adenomatous proliferation. Several morphologic variants of cystadenomas have bean described, including papillary-oncocytic, mucous, and seromucous subtypes. Cystadenomas arising from salivary glands are very rare and seromucous cystadenoma of parotid gland has not been reported in Korea so far. Cystadenomas of the parotid gland usually Present as asymptomatic slowly growing mass and those of the minor salivary glands produce smooth nodules that may be compressible. We performed a superficial parotidectomy in a patient with a seromucous cystadenoma. This may be the first report of seromucous cystadenoma of carotid gland in Korea.

TREATMENT OF EXCESSIVE SALIVARY DRAINAGE AFTER SUPERFICIAL PAROTIDECTOMY AND EXCISION OF AN ACCESSORY PAROTID GLAND TUMOR

The possible complications after parotidectomy are facial nerve palsy, Frey's syndrome, sialocele, salivary fistula, hematoma infection, and flap necrosis. Postoperative sialocele and salivary fistula are relatively uncommon and the management varies. We experienced a rare postoperative complication of excessive and prolonged drainage of saliva after superficial parotidectomy and removal of an necessary parotid gland tumor. The patient could be treated successfully with conservative management such as compressive dressing, restriction of oral intake of irritant food, maintenance of oral hygiene and the use of amitriptyline(antidepressant).

The Early Result of Anterior Rotational Osteotomy in the Treatment of Osteonecrosis of the Femoral Head / 영남의대학술지

In transtrochanteric rotational osteotomy to treat osteonecrosis of the femoral head, the necrotic superior anterior femoral head is rotated anteriorly around the longitudinal neck axis so that the weight bearing force is transferred to the intact posterior surface. The ratio of transposed intact articular surface of the femoral head to the weight-bearing surface of the acetabulum on postoperative anteroposterior view of the hip roentgenograph is the most important indicator of the prognosis. During the period from December 1992 to June 1994, we treated 31 hips in 28 patients who were indicated for the anterior rotational osteotomy among the patients of osteoncrosis of the femoral head. Among the patients, male were 27 and female was one. Age distribution was from 13 to 62 years old and mean age was 44.3. According to the Ficat and Arlet classification, II A was most in number as 16 II B was 7 and III was 8. As their etiolgic factors, alcohol was most in number as 18, steroid was 3, idiopathic was 5 and trauma was 2. The mean rate of the intact area of the posterior part of the femoral head to the total articular surface on the preoperative lateral view of the hip roentgenograph was 41.8%. The mean ratio of transposed intact articular surface of the femoral head to the weight bearing surface of the acetabulum was 53.8% Fixation devices were screws or dynamic hip screw.