OBJECTIVE Because of its special biological characteristics, myoblast might play a role in gene delivery and cell-to-biomaterial interactions. In this paper, the biological features of myoblast and its application on gene therapy and tissue engineering was discussed. METHODS Documents about proliferation and differentiation of myoblast were reviewed in details. The prospects of its application on gene therapy and tissue engineering were also presented. RESULTS Myoblast was important in muscle regeneration. The activation of myoblast to proliferate and differentiate was the very beginning of regeneration after injury. The cultured myoblast had high potential to proliferate, it was ready to fuse with each other and to form myotube (the special behavior of myoblast differentiation). Myoblast transplantation had been studied as a possible treatment for inherited myopathies, such as Duchenne muscular dystrophy. The transplanted myoblast could fuse with host myofibers, so the delivered target gene integrated into host. Several myoblast-mediated gene delivery system had been established, including the gene delivery of human factor IX (hFIX), erythropoietin (EPO) and clony stimulating factor-1 (CSF-1). Results from animal experiments demonstrated that myoblast-mediated gene delivery could be used as gene therapy for some inherited diseases. And recently, some authors have shown great interest in the interaction between myoblast and type I collagen gels. It was found that myoblast could keep on proliferating and differentiating in collagen gels and could form discoid, tubular materials. CONCLUSION Myoblast has great importance in gene therapy and tissue engineering. It is suggested that more efforts should be made in this field.
【Abstract】 Objective To investigate the effect of the volar capsular l igament complex on stabil ity of the wrist jointand to provide basic biomechanical theoretical criteria for cl inic appl ication of the external fixator. Methods Nine upperl imbs specimens (left 6, right 3) were taken from fresh adult cadavers to make wrist joint-bone capsular l igament complex specimens. Firstly, soft tissues of forearms and hands were resected and capsular membranes and l igaments were reserved to make the bone-articular l igament complex (normal specimen). Secondly, the volar capsular l igament complex was cut off from radial malleolus to ulnar malleolus (impaired specimen). Thirdly, the impaired volar capsular l igament complex was interruptedly sutured by the use of 4# suture silk (repaired specimen). To simulate cl inical operation with external fixator, the biomechanical test was done according to the sequence (normal, impaired, repaired, repaired and fixed, impaired and fixed). Statistical significance was analyzed through selected loads at the three different shifts (1.5, 2.0, 2.5 cm). Results According to the sequence (normal, impaired, repaired, repaired and fixed, impaired and fixed), when the shift was 1.5 cm, the different respective loads were (60.74 ± 20.60), (35.23 ± 13.88), (44.36 ± 20.78), (168.40 ± 29.21) and (139.00 ± 33.18) N, respectively. When the shift was 2.0 cm, the different loads were (138.46 ± 12.93), (87.17 ± 24.22), (97.52 ± 23.29), (289.00 ± 54.29) and (257.98 ± 55.74) N, respectively. When the shift was 2.5 cm, the different loads were (312.87 ± 37.15), (198.16 ± 37.14), (225.66 ± 30.96), (543.15 ± 74.33) and (450.35 ± 29.38) N, respectively. There was no statistically significant difference between the impaired and repaired specimens (P gt; 0.05). Similarly, there was statistically significant difference among the rest specimens (P lt; 0.05). The same statistical results were obtained when the two different shifts were compared. There was statistically significant difference at the three different shifts for the same specimen (P lt; 0.05). Conclusion Volar capsular l igament complex is an important anatomic structure to keep stabil ity of the wrist joint. The carpal instabil ity arises out of the injured complex. Repairing the injured complex only can not immediately restore stabil ity of the wrist joint. The external fixator can effectively help to diminish the relative shift of the impaired capsular l igament complex, to reduce the load of the repaired complex and to protect the complex accordingly. The device plays an important role in maintaining stabil ity of the wrist joint.
Objective To investigate the effect of perioperative body temperature on the survival of skin flap grafting. Methods From July 2005 to November 2006, 50 cases of Ⅰ-Ⅱ grade patients undergoing elective skin flap grafting were randomly divided 2 groups. Pharyngeal temperature (PT) and skin temperature(ST) were monitored and recorded every 15 minutes. Operativetime, anesthetic time, time from the end of operation to extubation, the volume of blood transfusion, the volume of fluid transfusion and the flap survival 7 days after operation were recorded. In the experimental group, the body temperature was maintained in normal range with water market and forced air heater. In the control group， the body temperature was only monitored without any treatment. Results There were no significant differences in operating room temperature, operative time, anesthetic time, the volume of blood transfusion and fluid transfusion between 2 groups(Pgt;0.05). After induction, PT decreased gradually inboth groups during the first 45 minutes, compared with the time point of intubation(Plt;0.05),but there were no significant differences between the 2 groups(Pgt;0.05); and ST rose in both groups during the first45 minutes, compared with the time point of intubation (Plt;0.05). After 45 minutes of induction, in the experimental group, PT was in the normal range(36℃), and ST didn’t change compared with that of the timepoint of induction(Pgt;0.05). In the control group, both PT and ST decreasedgradually and timedependently compared with the time point of intubation (Plt;0.05). In the experimental group, PT and ST at each time point were higher than those in the control group (Plt;0.05). All the skin flap grafts survived in the experimental group, and skin flap grafts necrosed in 2 cases in the control group.Conclusion Keeping normal body temperature can improve the survival ofskin flap grafting. Therefore, the body temperature should be monitored and maintained in a normal range.
OBJECTIVE: To observe the proliferation and differentiation properties of primary human embryonic skeletal myoblasts cultured in vitro. METHODS: The skeletal muscle samples were obtained from 20 to 25-week abortion fetus, the family history of inherited myopathies of parental generation was negative. With a modified method of Blau, the muscle sample was digested with trypsin and collagenase. The isolated cell suspension was a mixture of myoblasts and fibroblasts, the latter was removed by repeated attachment to culture dishes. The morphological, immunohistochemical observation, the proliferation and differentiation of primary myoblasts were studied. RESULTS: The isolated myoblasts were spherical in cell suspension and spindle-like after attached to culture dishes. The myosin specialized immunohistochemical staining was bly positive. A large quantity of skeletal muscle specialized creatine kinase (CK-MM) was synthesized in cultured myoblasts. Additionally, while the cell density of myoblasts increased, the monocyte myoblasts would fused to form multinucleated myotube. All those indicated that the cultured cells were myoblasts. Primary myoblasts proliferated quickly, the doubling time, measured in growth curve, was 4.8 days. CONCLUSION: A large number of myoblasts can be available with digestion and repeated attachment method. The cultured cells can be proved as myoblasts by morphological and immunohistochemical detection. The cultured myoblasts have good ability of proliferation and differentiation.
OBJECTIVE: To investigate the biological characteristics of continuously subcultured human embryonic skeletal myoblasts, and choose the optimal seeding cells for muscle tissue engineering. METHODS: Human embryonic skeletal myoblasts were subcultured in vitro. The growth curve, rate of myotube formation(RMF) were used to evaluate the proliferative and differentiation ability of myoblasts, and to investigate the influence of fibroblasts contamination on myoblasts. RESULTS: The beginning 6 passages of myoblasts showed b proliferative and differentiation ability. From the 8th to 20th passage, the rate of fibroblasts contamination was increased, it mainly showed the growth characteristics of fibroblasts with increased proliferation and low differentiation. After subcultured to the 20th passage, the degeneration of myoblasts was obvious. CONCLUSION: The myoblasts within 6 passages should be used as the seeding cells of muscle tissue engineering because of b proliferative ability and high rate of myotube formation.
目的:回顾性研究人工肱骨头置换治疗复杂肱骨近端骨折患者的肩关节的情况,以进一步提高疗效。方法:对我院2004年至2007年27例肱骨近端骨折患者采用肱骨头置换术治疗,术中修复关节囊和肩袖,术后随访5~38月,评价其肩关节功能。结果:采用半关节成形改良评分系统SSMH综合评分,优:5例,良:17例,可:5例,优良率:815%。肩关节活动:平均前屈上举:96°,外旋:36°,内旋至L2水平。X片示假体无松动断裂,位置良好。结论:对于复杂的肱骨近端骨折,人工肱骨头置换是有效治疗手段,能够最大限度恢复期肩关节活动功能。
Objective To retrospectively reviewed the operative therapy of the terrible triad of the elbow. Methods From October 2003 to September 2007, 10 cases of terrible triad were treated, with an elbow dislocation and an associated fracture of both the radial head and the coronoid process. There were 3 males and 7 females with the age of 18-66 years. The injury was caused by traffic accidents in 4 cases, fall ing from a height in 4 cases, and tumbl ing in 2 cases. The coronoid process fractures of the patients were 5 cases of type I, 3 cases of type II and 2 cases of type III according to Regan- Morrey classification. The radial head fractures of the patients were 1 case of type I, 6 cases of type II and 1 case of type IIIaccording to Mason classification, and their radial heads of the other 2 patiants were resected before they were in hospital. The general approach was to repair the damaged structures sequentially from deep to superficial, from coronoid to anterior capsule to radial head to lateral l igament complex to common extensor origin. And selected cases were repaired of the medial collateral l igaments and assisted mobile hinged external fixation to keep the forearm fixed in functional rotation position. The function of the elbows were evaluated with the criteria of the HSS2 score system. Results The other wounds healed by first intention except 1 case which had infection 7 days after operation and whose soft tissue defect in posterior elbow were repaired with the pedicle thoracoumbil ical flap. The patients were followed up 6 to 51 mouths (mean 24.9 mouths). The fracture heal ing time was 6 to 20 weeks (mean 9.6 weeks). Six mouths postoperatively, the mean flexion-extension arc of the elbow was 106.5° (85-130°), and the mean pronation-supination arc of the forearm was 138°( 100-160°) respectively. According to the criteria of the HSS2 score, the results were excellent in 4 cases, good in 4 cases, and fair in 2 cases. No compl ications such as stiffness and ulnohumeral arthrosis occurred. The radial nerve injury was found in 1 patient 1 day after operation who was treated with neurolysis, and the nerve function was recovered after 4-6 months. And heterotopic ossification occurred in 6 patients 6 months after operation and radiographic subluxation developed in 1 patient 36 months after operation, and conservative treatment weregiven. Conclusion The terrible triad of the elbow can lead to serious elbow instabil ity and should be treated with operationto restore the anatomic structures, to repair the articular capsule and the collateral l igament, using the adjuvant hinged external fixation and early exercise to avoid immobil ization and recover the articular function.
【Abstract】 Objective To investigate the effect of IGF-1 on the growth of primary human embryonicmyoblasts. Methods The method of incorporation of 3H-TdR was used to evaluate the abil ity of prol iferation of myoblasts.The count per minute (CPM) values of myoblasts at different concentrations(1, 2, 4, 8, 16 and 32 ng/mL) of IGF-1 were measured,and dose-effect curves were drawn to choose the optional concentration of IGF-1 to promote the prol iferation. Then theexperimental group of myoblasts received the addition of the optional concentration of IGF-1 in the growth medium, the controlgroup just received the growth medium. The flow cytometry was used to detect the cell cycle . The method of incorporation of3H-TdR was used to measure the peak-CPM. The myotube fusion rate was measured in myoblasts with different concentrations(0, 5,10, 15, 20, 25 and 30 ng/ mL) of IGF-1 in fusion medium, the dose-effect curves were also drawn, so as to decided the optional concentrationof IGF-1 in stimulating differentiation. Fusion medium with optional concentration of IGF-1 was used in experimentalgroup, and the control group just with fusion medium. The fusion rate of myotube and the synthesis of creatine kinase(CK) weredetected in both groups. Results The optional concentration of 5 ng/mL IGF-1 was chosen for stimulating prol iferation . It was shown that the time of cell cycle of control was 96 hours, but that of the experimental group was reduced to 60 hours. The results of flow cytometry showed that the time of G1 phase, S phase and G2M phase was 70.03, 25.01 and 0.96 hoursrespectively in control group, and were 22.66, 16.47 and 20.87 hours respectively in experimental group. The time-CPM value curves showed that the peak-CPM emerged at 96 hours in control group and 48 hours in experimental group, which was in agreementwith the results of the flow cytometry. The optional concentration stimulating prol iferation was 20 ng/mL IGF-1. Compared with control, the quantity of CK was increased by 2 000 mU/mL and the fusion rate was elevated by 30% in experimental group. Conclusion The concentrations of 20 ng/mL IGF-1 can elevat obviously the fusion rate and the quantity of CK. IGF-1 can enhance the prol iferation and differentiation of myoblasts via inducing the number of myoblasts at G1 phase and increasing the number of myoblasts at S and G2M phases.