ABSTRACT
<p><b>OBJECTIVE</b>To explore highly agglutinative staphylococcin (HAS) pomoting on tendon-bone healing after reconstruction of anterior cruciate ligament(ACL) in rabbits.</p><p><b>METHODS</b>Animal model of ACL reconstruction in 24 mature New Zealand white rabbits(3 months, 2.56 kg on average, either gender) were established using autologous digital long extensor tendon and randomly classified into 2 groups(HAS and control group), 12 rabbits for each group. HAS group was separately injected 0.1ml highly agglutinative staphylococcin immediately into tendon-bone interface during the operation and 2 days after operation. Control group was injected with the same dose of physiological saline for 3 days. All animals were sacrificed at 4, 8, and 12 weeks after operation for histological examinations. The specimens were stained with hematoxylin-eosin, picric acid-sirius red, VEGF immunohistochemistry stain, and toluidine blue to histologically analysis the total pathology changes of the tendon-bone healing tissue, the tendon bone interface morphology classification, hyperplasia and arrangement of collagen fiber, vascularization and new bone formation, respectively.</p><p><b>RESULTS</b>The Yamakado morphological interface results showed that the tissue healing at tendon-bone interface of the HAS group was better than that of the control group. The histological examination revealed that on the 4th week after operation, the tendon-bone interface of HAS group was filled with fibrous connective tissue. The proliferated fibroblasts, chondroblasts and the angiogenesis were rich. On the 8th week after operation, the healing tissue at the bone-tendon interface had developed into dense connective tissue, the neo-vessels were very rich, the collagen fibers were formed abundantly, some Sharpey's fibers spanning parts of the tendon-bone interface. On the 12th week after operation, the transition zones were full of Sharpey's fibers;the neo-vessels were not as much as the 8th weeks, but new bone formation was further increased and immature fibrocartilage appeared. For quantitative histological analysis at 4, 8 and 12 weeks after operation, the proportion of neo-vessel area and the area of now bone formation of the HAS group were all significantly higher than those of the control group(<0.05).</p><p><b>CONCLUSIONS</b>Under the synergy of staphylococcal enterotoxin C and other active ingredients, Highly Agglutinative Staphylococcin can significantly improve the tendon-bone healing after ACL reconstruction in rabbit knees, which is expected to be a new method to improve the clinical results of ACL reconstruction.</p>
ABSTRACT
<p><b>OBJECTIVE</b>To transfect antisense vector of human cyclooxygenase-2 (COX-2) gene into COX-2 highly expressing cholangiocarcinoma cell line QBC939 and explore its biological activities and role in carcinogenesis.</p><p><b>METHODS</b>QBC939 cells were transfected with antisense vector of human COX-2 gene using LipoVec transfecting technique. Transfected cells were selected with G418; COX-2 mRNA was examined using reverse transcription polymerase chain reaction (RT-PCR) and COX-2 protein expression was detected by immunocytochemistry using isozyme selective antibodies. The proliferative status of transfected cells was measured by using methabenzthiazuron (MTT) assay; Cell cycle and apoptosis were analyzed by using flow cytometry.</p><p><b>RESULTS</b>RT-PCR showed a lower COX-2 mRNA level in antisense vector transfected cells and immunocytochemistry showed a weaker COX-2 protein expression in antisense vector transfected cells. The antisense vector transfected cells proliferative index decreased significantly (P < 0.01), the percentage of S phase decreased remarkably (P < 0.05) in antisense vector transfected cells (9.27% +/- 1.91%) compared with that in QBC939 cells without transfection(16.35% +/- 2.87%), and the percentage of G0/G1 phase increased remarkably (P < 0.05) in antisense vector transfected cells (75.16% +/- 4.13%) compared with that in QBC939 cells without transfection (57.31% +/- 10.16%). Transfection with antisense vector of human COX-2 gene had no significant influence on the apoptosis in QBC939 cells (P > 0.05).</p><p><b>CONCLUSION</b>Transfection with antisense vector of human COX-2 gene could inhibit the proliferation of human cholangiocarcinoma QBC939 cells.</p>