PURPOSE:To investigate the approaches for transplanting retinal pigment epithelium. METHODS,Retinal pigment epithelial eells(RPR)of pigmented rabbits' eyes prepared by rotalne preparation of our institute,were transphmted in 18 unpigmemed rabbits'eyes.Eight eyes were undergone outer approach, i.e., transplanting the RPR cells to the subretinal space of recipient eyes by way of perforating sclera and choroid;while 10 eyes were undergone internal approach by way of the routine procedure of vitrectomy with making artificial localized retinal delachment. Light and transmisskm electrone microscopy examination were done at 10th, goth, 40th and 90th day after the operation. RESULTS: In internal approach group,tbe operated eyes,revealed no difference in thickness of the neural retinal layer in transplanted and non-transplanted area 40 days after operation tinder light microscope. Transmission electrone microscopy revealed postoperatively the transplanted RPE cells attached to the Brucb's membrane and the outer segments of photoreeeplive ceils located at a normal position at the 40th dayland the secondary lysozymes with engulfed outer segment were found in the Iransplamed cells at the 90th day. Tbe outer approached operations in eight eyes were failed owing to ehoroid hemorrhage or perforation of retina. CONCLUSION:The internal appraach procedure is much effebtive and practical for transplantation of RPE cells. （Chin J Ocul Fundus Dis,1997,13:160-162）
One eye each in 3 groups of 12 pigmented rabbits after bilateral vitrectomy received 0.5mg, 1mg or 2mg triamcinolone acetonide (TA), respectively. The fellow eye received only balance saline solution as control. Ophthalmoscopy and electroretinography were performed during 1 day to 38 days after vitrectomy and drug injection. Light and electronmicroscopic studies were done on the 28th day. The particles of drug were visible on day 28 in all TA-treated eyes. Administration of 0. 5rug and 1mg TA did not result in different changes in ERG b-wave amplitudes compared with those in control eyes(P＞0. 05). There were significant elevations of ERG b-wave in 2mg TA eyes compared to the control eyes(Plt;0.05), Both ligbt and electronmicroscopy of the retina in these groups were almost normal. The results showed no Toxielties in TA treated eye up to 2mg after vitrectomy. This offers the experimental evidence as a baseline for combining TA with vitrectomy to reduce recurrence of proliferative vitreoretinopathy. （Chin J Ocul Fundus Dis,1996,12: 105- 107）
Objective To provide a reliable experimental model for gastroesophageal reflux (GER) study. Methods Twenty Japan 5-month-old male rabbits wererandomly divided into two groups: group cardiomyotomy(n=10), group partial cardiomyectomy(n=10). The operations of cardiomyotomy and parital cardiomyectomy were performed in 2 groups respectively. All the animals underwent intraesophagealpH detection 1 week before operation and 4 weeks after operation. The mean changes of reflux ratios were compared between before operation and after operation.Results In gastroesophageal reflux ratio between before operation and after operation, there was no significant difference in group cardiomyotomy (1.98%±1.52% and 4.32%±2.39%, Pgt;0.05) and there was significant difference in group partialcardiomyectomy（1.56%±1.57% and 13.56%±3.27%, Plt;0.05）. Conclusion The reliable experimental model of GER can be made with procedure of partial cardiomyectomy. It can be used in estimating the operative procedure of antireflux and is conducive to dynamic observation and study of esophagitis.
OBJECTIVE To assess the treatment effect of sodium hyaluronate (HA) on experimental temporomandibular joint (TMJ) osteoarthritis of rabbits in comparison with prednisolone (PS). METHODS The upper compartments of both TMJs of 12 Japanese White Ear Rabbits were injected with 0.2 ml of 1.6% papain, 3 days after the right TMJs were injected again with same amount of papain to induce osteoarthritis with different severity levels. Except 1 rabbit was died accidentally. After one week from final injection of papain, the upper compartments of both TMJs of 6 rabbits were injected with HA 1.3 mg, 5 rabbits with PS 1.6 mg weekly for 4 times. At 3, 5 and 7 weeks after the final injection, the rabbits were sacrificed and the TMJs were pathologically examined. RESULTS The TMJs receiving PS showed predominant structural disorganization, and the right TMJs had much severe pathology. The manifestations were fibrillation, thinner or flaking of the articular cartilage of the temporal part of the joint, and the articular surface was covered with fibrous tissue. Whereas the TMJs receiving HA injections demonstrated limited changes of cartilage, less fibrillation, only local loss of cartilage on outside layer of the surface. In vicinity of the defect area, cluster of the chondrocytes appeared. Pathological scores of the TMJs receiving HA were significantly less than those of the TMJs revieving PS. CONCLUSION The results suggest that hyaluronate have effect of cartilaginous reparation and protection for the osteoarthritis of rabbit. While prednisolone has no help or worsened for articular cartilage reparation.
Objective To study the effect of decorin in the suppression of postoperative flexor tendon adhesion. Methods Eighteen Japanese large ear white rabbits underwent complete transection of the Ⅱ digit flexor digitorum profundus tendon in zone Ⅱ and defects immediately were repaired using the modified Kessler technique with -0 nonabsorbable monofilament suture. The site of the right repaired tendon was then injected with 100 μl of decorin(0.25mg/ml) as test toe, the site of the left repaired tendon with 100 μl of PBS as control toe. Inevery group, rabbits were killed and the feet were prepared for biomechanical testing, macroscopic examination and histological inspection. Results In every group, biomechanical testing demonstrates that the sliding distances and the rangs of motion significantly increased in the test toe compared with the control toe(Plt;0.05); macroscopic examination demonstrated that the tendon adhesions of the test toe were significantly reduced when compared with the control toe. In the tese toe, hematoxylin and eosin staining revealed that the hyperplasia of fibroblast was significantly delayed and the collagen fibrils arranged regularly and hadthe normal diameters. Conclusion Decorin can significantly reduce the flexor tendon adhesion formation, adjust collagen fibrillogenesis and promote the tendon healing.
Objective To investigate the effect of the injectable osteoinductive material with fibrin sealant(FS) as a carrier compounded with bone morphogenetic protein (BMP) on the proliferation and differentiation of marrow stromal cells (MSCs) towards osteoblasts and to provide the experimental foundation for the clinical application. Methods MSCs were extracted and cultured from bone marrow of the 3-day-old rabbit, and the third generation culturedMSCs were studied. The experiment included the experimental group(FS,including 1 μg/ml rhBMP-2), FS control group（FS）and blank control group (no material).The proliferation rate, the adhesive rate, the expression of the collagen Ⅰ and alkaline phosphatase, cell growth condition in the material and the ultrastructure of MSCs were investigated by electron microscopy, histochemistry and cell culture. Results The proliferation rate and the adhesive rate of MSCs in experimental group was significantly higher than those in blank control group ,but lower than those in FS control group （P＜0.05）. The expression level of thecollagen Ⅰ and alkaline phosphatase in the experimental group was significantlyhigher than those in all control groups（Marrow stromal cells Fibrin sealant Bone morphogenetic protein Cell culture Rabbits0.05）. Scanning electron microscope showed that the surface of material was rough and had many pores and that celland material mixed. Transmission electron microscope showed that MSCs of the experimental group were mostly of the phenotype of osteoblasts with relatively lowproliferation activity and high differentiation degree toward osteoblasts and with plenty of extracellular matrix and collagen fibers. MSCs of FS control group had low differentiation degree toward osteoblasts with few extracellular matrix and collagen fibers and high proliferation activity. MSCs of blank control group had low differentiation degree toward osteoblasts with few extracellularmatrix and collagen fibers, and low proliferation activity. Conclusion The injectable osteoinductive material with fibrin sealant as a carrier compounded with BMP could significantly accelerate the differentiation of MSCs towards osteoblasts. But it could not significantly accelerate the proliferation activity of MSCs.
Objective To compare the effect of guiding boneregeneration between l-ethyl-3(3-diaminopropyol)-carbodiimide(EDAC)crosslinked acellular bovine pericardium (ABP) and medical collagen membrane (CM). Methods Defects of 7 mm×7 mm×5 mm were created in both mandibles of 24 rabbits, which weighted 2.6～3.5 kg. One side defect was covered with EDAC-crosslinked ABP(EDAC-crosslinked ABP group), the other side defect with medical CM as control(CM group). The ability of bone defect repair and change ofboth membrane materials were evaluated by gross observation, histological study and computer graphic analysis in the 4th, 8th, 16th and 24th weeks after operation. Results The surface of bone defects was even, consistent with adjacent normal bonein EDACcrosslinked ABP group, while that of bone defects was of no evenness in CM group in the 16th and the 24th weeks. The histological observation showed that bone trabecula formed in the EDAC-crosslinked ABP group and fibrous connective tissue was seen in CM group in the 16th and the 24th weeks. There were no significant differences in new bone percentage of bone defects between 2 groups inthe 4th and the 8th weeks(P＞0.05). In the 16th week new bone percentage of bone defects was 81.99%±3.92% in EDAC-crosslinked ABP group and 76.35%±4.29% in CM group, showing significant difference (Plt;0.05). The average percentage of absorption in EDAC-crosslinked ABP group was 16.57%, 27.94%, 65.61% and85.72% in the 4th, 8th, 16th and 24th weeks respectively, while that in CM group was more than 50% in the 4th week and completely degraded at the end of 8 weeks. Conclusion EDAC-crosslinked ABP has a better effect on guiding bone regeneration than CM in the repair of bone defects.
【Abstract】 Objective To establ ish a stable animal model for glucocorticoid-induced avascular necrosis of femoral head in rabbits. Methods Thirty-six adult New Zealand rabbits were randomly divided into four groups:ten were injected twice with l i popolysaccharide (group A), ten were treated with a combination of l i popolysaccharideand methylprednisolone (group B), ten were injected three times with methylprednisolone (group C), and six wereinjected normal sal ine as a control (group D). MR imaging was performed in the rabbits before the first injection ofl i popolysaccharide or methylprednisolone, and at 2, 4, and 6 weeks after the last injection of l i popolysaccharide ormethylprednisolone. Histopathological changes in the femoral heads were observed by l ight microscope and transmission electron microscope at the end of six weeks after the injection. Vascular infusion with Chinese ink was made to evaluate the morphological changes of blood vessels in the femoral head. The percentage of trabecular bone area and empty lacunae and microvascular density were measured. According to the histological and MR imaging appearance of the femoral heads in all groups, the incidence of osteonecrosis of every group was calculated. Results Listlessness, blepharal hyperemia,less activity and reduced diet were found in the rabbits of groups A and B after injected with l ipopolysaccharide. At 3 weeks after the final injection, the body weight of groups B and C was decreased. At 4 weeks after the final injection, the body weight of groups A and D was increased. No abnormal signal could be detected on MR images in rabbits of all groupsbefore injection and at 2 weeks after the injection. At 4 weeks and 6 weeks after the last injection, irregular low signal on T1-weighted images and irregular low or high signal on T2-weighted images could be detected on MR images in rabbits of groups B and C, no abnormal signal could be detected on MR images in rabbits of groups A and D. At 6 weeks after the last injection,the trabecular bone of group B became thin and sparse, some were broken. The percentages of empty lacunae were 11.8% ± 4.7%, 34.4% ± 6.2%, 20.0% ± 4.7% and 9.3% ± 4.6%; the percentages of trabecular bone area were 59.2% ± 6.8%, 40.1% ± 6.0%, 51.5% ± 5.6% and 63.2% ± 8.3%; and the microvascular densities were 14.3% ± 2.7%, 4.5% ± 2.1%, 10.2% ± 3.1% and 15.4% ± 4.1% in groups A, B, C and D respectively. There were statistically significant differences between group B and groups A, C, D (P lt;0.01). The fatty tamponade accumulated in the medullary cavity and intramedullary vascular sinusoids were pressed by the l ipocytes and became narrow. Limposomes were found in osteocytes and vascular endothel ia of group B and group C. Osteocytes of group B crimpled and pyknosis or karyolysis of chromatin were observed in these osteocytes, nuclearmembrane of the osteocytes was discontinous. Vascular endothel ia became swollen and the cell junctions widened or were destroyed in groups A and B. The incidence of osteonecrosis in group B (88.9%) was higher than that in group C (22.2%, P lt; 0.05). There was no osteonecrosis occurred in groups A and D . Conclusion Methylprednisolone combined with l ipopolysaccharide can induce typical rabbit model for early avascular necrosis of femoral head.
To investigate the preventive effect of TGF-β1 neutral izing antibody on collagen production and adhesion formation of flexor tendon. Methods Tendon fibroblasts, epitenon tenocytes, and endotenon tenocytes were obtained from 6 New Zealand rabbit flexor tendons. Each cell culture was supplemented with 1 ng/mL of TGF-β along with increasing dose of TGF-β1 neutral izing antibody. Col I production was measured by enzyme-l inked immunoabsorbent assay after 3 days. Eighty-four adult New Zealand White rabbits forepaws underwent sharp transection of middle digit flexor digitorumprofundus and immediate repair. Then the rabbits were divided into three groups: the normal saline (NS group, n=36), 1.0 µg/ mL TGF-β1neutral izing antibody (1.0 µg/mL TGF-β1group, n=36) and 2.0 µg/mL TGF-β1 neutral izing antibody (2.0 µg/mL TGF-β1 group, n=12) were injected in tendon sheath respectively. Tendons were harvested at 4 and 8 weeks for biomechanics testing, histological evaluation and scanning electron microscope observation. Tendons were harvested at 1, 2, 4 and 8 weeks to determine the mRNA expression of TGF-β1 and Col I by in situ hybridization. Results ELISA exhibed that TGF-β1 enhanced Col I production and the neutral izing antibody significantly inhibited TGF-β1-induced Col I production in all 3 cell culture with a dose-dependent. At 4 and 8 weeks after operation the gl iding excursion of the tendon and the simulated active flexion in NS group were less than that of 1.0 µg/mL TGF-β1 group and 2.0 µ g/mL TGF-β1 group. There was significant difference between NS group and 1.0 µ g/mL TGF-β1 group, 2.0 µ g/mL TGF-β1 group (P lt; 0.05). The tendon anastomosis breaking strength showed no significant differences among three groups (P gt; 0.05). Scanning electron microscope and histological observation showed that collagen fibers arranged irregularly in NS group, but arranged regularly in 1.0 µ g/mL TGF-β1 group and 2.0 µ g/mL TGF-β1group at 4 and 8 weeks after operation. The in situ hybridization results revealed that TGF-β1 and Col I mRNA expression in 1.0 µ g/mL TGF-β1 group was lower than that in NS group at each time. There was significant difference between two groups (P lt; 0.05). Conclusion TGF-β1neutral izing antibody can inhibit the function of the TGF-β1 effectively and prevent adhesion formation after the flexor tendon injured and repaired.
Objective To explore the possibility of small intestinal submucosa (SIS) for reconstruction of urethral defect. 〖WTHZ〗Methods Twenty-four male rabbits weredivided into 4 groups: group A (the tubulate SIS graft for urethral repair), group B (control group, urethral tubulate defect), group C (the SIS patch graft forurethral repairs), group D (control group, urethral part defect). Then the regenerative segment was studied with histological technique by hematoxylineosin straining and immunohistological straining for α-actin after 6 and 12 weeks postoperatively. The retrograde urethrography and urodynamics were used to evaluate the function of the regenerative urethra at 12 weeks after operation. Results In groups A and C, at 6 weeks after operation, the luminal surface of matrix was completely covered by urothelium, minimal SIS graft was observed in the extracellular matrix, new smooth-muscle cells was confirmed; however, more inflammatory cells were observed in the host-matrix anastomosis in group A than in group C. At 12 weeks postoperatively, the regenerative tissue was equivalent to the normal urethral tissue and SIS disappeared in group C, but some minimal SIS grafts were observed in group A. In groups B and D, urethral strictures and fibrous connective tissue were observed except ３ cases. The urethrography showed wide smooth urethral in group A and C, meawhile urodynamic evaluation didn’t demonstrat significant difference(P＞0.05) in the bladder volume and the maximum urethral pressure between preoperation and postoperation in group A or group C. Conclusion SIS can be a useful material for urethral repair in rabbits, the SIS patch graft is superior to the tubulate SIS graft in urethra reconstruction.