Objective To investigate the repairative effect of local high expression of glial cell line-derived neurotrophic factor (GDNF) in the repair of sciatic nerve defects. Green fluorescent protein (GFP) gene was used as reporter gene. Two groups including gel matrix control group and gel matrix plus MSCs group were set ( 10 rabbits per group). Methods GDNF secreting mesenchymal stem cells (MSCs) mediated by lentiviral vectors were suspended in Matrigel to produce the artificial graft, and then it was locally implanted to a 20 mm-long sciatic nerve defect in rabbits. Results In the GDNF group,the nerve continuity was restored in seven rabbits and the functional amelioration of the wounded limb was apparent. While there found no restoration of the nerve continuity in the control groups. The migration distance of GDNF secreting MSCs was 20 mm, suggesting a good integration of the transplanted cells with host cells. The glial fibrillary acidic protein (GFAP) + green fluorescent protein (GFP) and -100 protein GFP accounted for 60% and 70% respectively in the experimental group, while it was only 40% and 30% in gel matrix plus MSCs group. Conclusions Local implantation of GDNF secreting MSCs can promote the regeneration and functional recovery of the sciatic nerves. GDNF seems to play an important role in inducing transdifferentiation of MSCs to Schwann cell lineage.

Background and purpose:Primary thyroid lymphoma (PTL) is uncommon in clinic with quite different treatment from that of other malignant thyroid tumors. Therefore, to achieve complete understanding of PTL has crucial signiifcance. This study aimed to investigate the clinical and computed tomography (CT) characteristics of PTL.Methods:The clinical and imaging data from 22 patients with PTLs conifrmed by pathology were collected. The clinical symptoms of patients, the site, size, shape, margin, CT value and enhancement pattern, relation with surround-ing tissues of PTLs and cervical lymph nodes were summarized retrospectively.Results:All the 22 patients including 8 males and 14 females had an average age of 60 years (range: 39-77 years). Twelve PTLs rapidly progressed in short term and the rest expanded slowly. The tumors involved bilateral thyroid in 11 cases, unilateral thyroid in 8 cases and both right lobe and isthmus in the remaining 3 cases. The long and short ranges were (12-104) mm and (11-71) mm. The solitary, multiple and diffuse nodules distributed in 5, 5 and 12 patients, respectively. In axial plain CT scans, low density appeared in 15 patients, isodensity in 7 patients, calciifcation inside the lesion in 0 patient, and necrosis in 5 patients. Nineteen PTLs manifested slight or moderate enhancement, and 3 marked enhancement in contrast-enhanced axial CT images. Homogeneous density and mixed density were demonstrated in 13 and 9 cases, respectively. Trachea and esophagus was pushed in 17 and 5 cases, tumors were involved into superior mediastinum in 12 cases and enlarged lymph nodes were demonstrated in 8 cases.Conclusion:If a solid thyroidal mass in an old female patient rapidly pro-gresses in short term and CT scans show homogeneous and low density, slight or moderate enhancement, and diffusive swelling with compression and invasion of surrounding tissues, it has a high possibility of PTL.

Objective To analyze the effect of clavicular hook plate (CHP) in treating dislocation of the acromioclavicular joint and fractures of the distal clavicle. Methods From July 2000 to May 2001, 12 cases with acromioclavicular joint dislocation or distal clavicle fractures were treated using CHP and its effect evaluated. Results All patients got good reduction and fixation and 2 weeks after operation they obtained satisfactory motion with average 90 degrees of flexion and 90 degrees of abduction. One patient suffered from impingement of the shoulder joint because of unsatisfactory preliminary flexion but the joint function was not affected posterior to extraction of inernal fixation. The X-ray showed good reduction in all patients. No re-fracture or subluxation occurred after removal of implants with 100% of joint function recovery. Conclusions CHP is a reliable way for acromioclavicular joint dislocation and distal clavicle fractures.

Objective:To investigate the levels of parathyroid hormo ne -related protein(PTHrP) in mandibular condylar cartilage during mandible forwar d positioning in different seasons. Methods:64 SD rats were rand omly divided into four groups according to seasons. Orthodontic appliance was us ed in 32 rats for 12 hours each day in daytime for mandibular protrusion. 8 rats were sacrificed at each season time point.Condyle samples were processed for PT HrP detection by a two-site immunoradiometric assay (IRMA) method.Another 32 ra ts without treatment were used as the controls.Macroscopic and microscopic appro ach were applied to analyze the results. Results:The level of P THrP in mandibular condylar cartilage(MCC) in the group of orthodontic treatmen t was higher than that in the control group(P

0.05). Radiographic analysis showed quite good results in 77 cases. Complications included delayed union in six cases, severe stiffness in one and neuropraxia in two. Conclusions Open reduction and internal fixation of intracondylar humeral fractures is a safe and effective technique. Meanwhile, triceps-split approach and olecranon osteotomy can obtain same clinical outcome for intracondylar humeral fractures.

Objective To investigate clinical results of shoulder hemiarthroplasty in treating comminuted proximal humeral fractures. Methods Shoulder hemiarthroplasty was performed from May 1997 to June 2004 in 28 cases with comminuted proximal humeral fractures who were followed up for mean 2.1 years. American Shoulder & Elbow Surgeon (ASES) score was adopted for evaluating pain after operation, range of active movement and function of daily work. Results Mean ASES score was 87.9(67-96 scores), with mean forward flexion of 132?, external rotation of 40?, mean VAS score of 2.6 and internal rotation at T_ 10 level. Strength and function of 23 cases reached 80% of the normal side six months postoperatively and 90% of the normal side one year postoperatively. Of all cases, 82% were satisfied with the treatment. Conclusion Only reconstruction of normal humeral length, tuberosity fixation and persevering rehabilitation can contribute to a successful result of hemiarthroplasty for the comminuted proximal humeral fractures.

[Objective]To explore the indications and operative techniques for comminuted fracture of proximal humerus. [Method] Twelve patients with fracture of proximal humerus were chosen, observation was made after locking proximal humerus plate fixation with anterior acromioplasty. [Result]The average follow-up period were 12 months (6～24months). All patients' fracture in surgery group had been union and all shoulder had good functions. No incidence of avascular necrosis and nonunion was found. [Conclusion]Rigid fixation of displaced comminuted fractures of proximal humerus with anterior acromioplasty is a simple and effective technique to prevent subacromial impingement syndrome after surgery. Precise osteotomy and early postoperative exercises are the key to success.

[Objective]To study the effect of repairing of rat peripheral nerve defect with engineering artificial nerve composed with Schwann cells and poly lactic glycoli aced(PLGA).[Method]Human Schwann cells were vaccinated into PLGA tube with polyglactin 910.Sixty SD rats were divided into 3 groups randomly with 20 rats in each one: group A,self-nerve graft;group B,Schwann cells artificial nerve;group C,pure PLGA.Evaluations of electrophysiological and histological examines were carried out 8 weeks ad 12 weeks after operation.[Result]The outcome of group B showed similar to group A in general and histological study,however it expressed slightly lower in electrophysiological study,muscle weight and nerve fiber quantity.Marked neuron could be found in spinal cord after group B had been traced.Large number of regeneration nerve fibers could be seen from electron microscope.[Conclusion]The tissue engineering artificial nerve composed with Schwann cells is able to repair 20 mm defects of peripheral nerve,and it has an approximate treatment effect to the self-nerve grafting.

【Objective】To evaluate the therapeutic effect of comprehensive therapy for supine and prone external rotationed ankle fracture.【Methods】Thirty-nine patients with supine and prone external rotationed ankle fracture were treated with manipulative reduction,plaster and splint fixation,functional exercises and steaming with herbal medicine decoction(mainly composed of Herba Lycopodii,Herba Speranskia tuberculatae,Caulis Spatholobi,Semen Persicae,Flos Carthami,Radix Angelicae Sinensis,Rhizoma Chuanxiong,Myrrha,Lignum Sappan,Rhizoma Drynariae,Radix Dipsaci,Radix Achyranthis Bidentatae,Ramulus Cinnamomi,etc.)【Results】X-ray film after reduction showed that apposition of fracture was good in 39 patients.The fixation time ranged from 6~11 weeks,averaged 8 weeks.The fracture union achieved in all of the patients,and the time for union was 53~84 days,averaged 58 days.The therapeutic effect in 39 patients was as follows:excellent in 28,good in 6,ordinary in 3,ineffective in 2 and the excellent and good rate being 87.2%.【Conclusion】A satisfactory effect can be achieved when applying proper reduction methods for different types of ankle fracture,and when adopting functional exercises and steaming with herbal medicine decoction.

Objective To discuss the effects of peritoneal dialysate (PDS) on the expression of aquaporin-1 in rat peritoneal mesothelial cells (RPMCs). Methods The in vitro cultured RPMCs were divided randomly into 4 groups, and stimulated respectively with 1640 culture medium containing 10% fetal calf serum (negative control), and three kinds of PDS (containing respectively 4.25% glucose, 4.25% mannitol or 1.5% glucose) for 3 hours. Indirect immunofluorescence assay (IFA) and flow cytometry (FCM)were employed to detect the expression of aquaporin-1 in RPMCs stimulated by different kind of PDS as above. Results Compared with negative control and the group with PDS containing 1.5% glucose, the expression of aquaporin-1 on the mesothelial cells of the group with PDS containing 4.25% glucose and that containing 4.25% mannitol was significantly up-regulated (P0.05). Conclusion PDS with higher osmotic pressure (OP) can enhance the expression of aquaporin-1 in RPMCs. For PDS with same OP (PDS containing 4.25% glucose or PDS containing 4.25% mannitol), those containing glucose can enhance the expression of aquaporin-1 more effectively than that PDS containing mannitol. This result indicates that glucose or its degradation products may be the independent factors in enhancing the expression of aquaporin-1 of RPMCs.