Objective To study the mechanism of restenosis of the vein graft and the effect of the grafting injury to the vein graft. Methods One side of the 36 healthy rabbits was randomly chosen as the V-A group, and on the side a 1.5cmlong femoral vein was obtained, and an 0.5-cm-long segment of the obtained femoral vein was separated as the control group. The remaining 1-cm-long femoral vein was inverted and was autogenously implanted into the femoral artery on the same side of the rabbit. The other side of the rabbits was chosen as the V-V group, and on this side a 1-cm-long femoral vein was obtained ex vivo and then was sutured in situ. The vein grafts on both sides were harvested 4 weeks after operation. The specimens from the harvested vein grafts were stained with HE and theelastic fiber Victoria blue for an observation on the histological changes in the walls of the vein grafts, and the specimens were also stained by the immunohistochemistry of the proliferating cell nuclear antigen (PCNA) for an observation on the wall cell proliferation of the vein grafts. The changes in the ultrastructure of the proliferated wall cells of the vein grafts were observed under electron microscope. The two sides of the rabbits were compared. Results The smooth muscle cells of the media developed hyperplasia, but theintima and the media remained unchanged in their thickness (3.50±0.41 μm, 12.23±1.59 μm) in the V-V group, with no difference when compared with the control group (3.40±0.37 μm, 12.14±1.62 μm); however, when compared with the V-A group (25.60±3.21 μm, 21.30±2.47 μm),there was a significant difference in the thickness (Plt;0.01). There were no cells positive for PCNA by the immunohistochemistry examination in the control group. The cells positive for PCNA were found in the intima and the media in both the V-V group and the V-A group; however, the percentageof the cells positive for PCNA in the intima and the media was significantly greater in the V-A group than in the V-V group (16.4%±1.9% and 36.5%±3.7% vs 5.9%±1.3% and 23.4%±3.4%, Plt;0.01). In the V-V group, the endothelial cell could be observed under transmis-sion electron microscope, which was flat and had a processlike villus at its free end, and the endothelial cells were closely arranged andhad hyperplasia of the smooth muscle cells in the media. But in the V-A group,the endothelial cells had an obvious hyperplasia with an irregular shape and a widened space between the cells, and in the intima a great amount of the smooth muscle cells could be observed, which had a broken basement membrane. The smooth muscle cells also had an obvious hyperplasia in the media. The shape and alignment of the endothelial cells in the control group were similar to those in the V-V group, but the hyperplasia of the smooth muscle cells was not observed in the media. Conclusion The grafting injury can cause hyperplasia ofthe vascular wall cells, and if the hemodynamics is changed simultaneously, more serious hyperplasia and cell migration can be observed from the media to the intima, resultingin restenosis of the blood vessels. So, if we can reduce the grafting injury and improve the microcirculation of the vein graft, we may find out the methods ofpreventing restenosis of the vein graft. The animal model of the V-V graftcan help to understand the mechanism of restenosis of the vein graft.
Objective To evaluate the effect of WO-1 on repair of the bone defect in the New Zealand rabbit radius by an oral or local administration. Methods Bone defects were surgically created in the bilateral radii of 36 Zealand rabbits (1.6-2.0 kg), which were randomly divided into3 groups. In Group A, the defective areas were given WO-1 0.1 ml (50 mg/ml) by the local injections; in Group B, the rabbits were given WO-1 5 mg each day by the oral administration. Group C was used as a control group. Among each of the 3 groups, 4 rabbits were randomly selected and were sacrificed at 20, 30 and 60 days after operation, respectively. Then, the serological, X-ray and histological examinations were performed. Results The serum alkaline phosphatase and bone glaprotein levels were significantly higher at 20 and 30 days after operation in Groups A and B than in Group C, but significantly lower at 60 days after operation in Groups A and B than in Group C（Plt;0.01）. The X-ray and histological examinations at 20, 30 and 60 days after operation revealed that the callus formation and remodeling were earlier in Groups A and B thanin Group C, and the remodeling was earlier and better in Group A than in Group B. Conclusion WO-1 can promote the repair of the radial defect in a rabbit; however, further studies on the doseeffect relationship, administration time, and administration route are still needed.
Objective To compare the difference of preparing the acellular larynx scaffold between perfusion method and immersion method, and find better way to make acellular larynx scaffold for tissue engineering. Methods Twenty 6-month-old male New Zealand rabbits, weighing 2.0-2.5 kg, were divided into perfusion group (n=10) and immersion group (n=10) at random. All the larynxes were excised in a sterile fashion. The acellular larynx scaffold was obtained by perfusionmethod and immersion method respectively, and then comparative examinations were performed by the macroscopicview, histological view, scanning electron microscope (SEM), cartilage vital ity assay and toluidine blue staining. ResultsMacroscopic view showed that the larynxes perfused by sodium dodecyl sulphate (SDS) became transparent after 2 hoursof perfusion, but the larynxes immersed by SDS over 16 hours still appeared pink-white. Histology and SEM indicated thatcompared with immersion group, perfusion group showed better acellular effect, more ventages and collagen fibers wereretained, no intact cell or nuclei remained in acellular matrix and chondrocytes were still survival. The porosity was 85.39% ± 3.16% in perfusion group and 34.72% ± 4.51% in immersion group, showing significant difference (P lt; 0.01). The chondrocyte vital ity rate of perfusion group (86.93% ± 1.52%) was higher than that of immersion group (77.73% ± 1.66%), showing significant difference (P lt; 0.01). Toluidine blue staining showed that the chondrocyte heterochromaty was ber in perfusion group than that in immersion group. Conclusion Compared with immersion method, perfusion method is a better way to construct acellular larynx scaffold because it can achieve better acellular effect and retain chondrocyte vital ity at the greatest extent in the acellular larynx scaffold.
The comparison made between two experimental models with obstructive jaundice, which were newly established reversible model and traditional bile duct ligation and internal drainage model, showed that the new model was superior to the traditional one. This study suggests that the new model would be an ideal model, which could replace the traditional one for studying obstructive jaundice.
ObjectiveTo systematically review the efficacy of moxibustion in the treatment of model rabbits with knee osteoarthritis (KOA).MethodsCNKI, WanFang Data, VIP, CBM, PubMed, EMbase and The Cochrane Library databases were electronically searched to collect animal experiments on moxibustion in the treatment of model rabbits with KOA from inception to January 31st, 2019. Two reviewers independently screened literature, extracted data, and assessed the risk of bias of included studies. Meta-analysis was then performed by using RevMan 5.3 software.ResultsA total of 13 articles involving 226 model rabbits were included. The results of meta-analysis showed that moxibustion could reduce Mankin score (MD=−6.47, 95%CI −7.63 to −5.32, P<0.000 01), positive expression rate of chondrocyte apoptosis (MD=−22.21, 95%CI −23.22 to −21.21, P<0.000 01), level of IL-1β in joint fluid (SMD=−8.40, 95%CI −15.09 to −1.72, P=0.01), NO content in joint fluid (SMD=−11.03, 95%CI −17.87 to −4.19, P=0.002), the level of serum IL-1β (MD=−19.94, 95%CI −23.61 to −16.27, P<0.05), and serum NO content (MD=−22.69, 95%CI −28.77 to −16.61, P<0.05) of model rabbits with KOA.ConclusionsCurrent evidence shows that moxibustion can improve articular cartilage injury, strengthen chondrocyte activity, inhibit the inflammatory response, and inhibit chondrocyte apoptosis of model rabbits with KOA. Due to the limited quality and quantity of the included studies, more high-quality studies are required to verify the above conclusions.
Objective To study the biological activities ofthe nerve regeneration conditioned fluid (NRCF), especially to further separateand identify the protein bands of the relative molecular mass of (232-440)×103. Methods The silicone nerve regeneration chambers were implanted between the cut ends of the sciatic nerve in 6 New Zealand white rabbits (weight, 1.8-2.5 kg). The proteins in NRCF were separated by the native-polycrylamide gel electrophoresis (Native-PAGE), the protein bands of the relative molecular mass of (232-440)×103 were analyzed by the Shotgun technique, liquid chromatography, and mass spectrometry. Results The Native-PAGE result showed that there was 1 protein band of the relative molecular mass over 669×103, (232-440)×103 and (140-232)×103,respectively, and 6 bands of the relative molecular mass of (67-140)×103.Besides, 54 proteins were identified with at least 2 distinct peptides in 1 protein band of the relative molecular mass of (232-440)×103, including 4 unnamed protein products, mainly at the isoelectric points of 5.5-8.0 and of the relative molecular mass of (10-40)×103. Based on their functions in the protein database, allthe identified proteins in this study were classified into the following 5 groups: conjugated protein (43%), transport protein (30%), enzyme (6%), signal transducer (4%), and molecular function-unknown protein (17%). At the subcellular localization of the identified proteins, there was mainly a secreted protein (63%), and the remaining proteins were localized in the membrane and cytoplasm. Conclusion Native-PAGE and the Shotgun technique can effectively separate and identify proteins from NRCF, and can identify the components of the protein band of the relative molecular mass of (232-440)×103 and provide basicinformation on the unnamed protein products in NRCF.
To detect the influence of raloxifene (RLX) on fracture heal ing in rabbit. Methods Eighty healthy New Zealand white rabbits (44 females and 36 males) weighing 1.9-2.1 kg were used. A 0.5-cm bone defect model in the mid-diaphysis of the left forel imb radius was establ ished in 72 rabbits, which thereafter were divided into 4 groups (n=18 per group, 10 females and 8 males): groups A, B and C received 7.5, 15.0 and 30.0 mg/ (kg• d) RLX, respectively, from the 2nd to the 50th postoperative day; group D received no further treatment. The rest untreated 8 rabbits (4 females and 4 males) served as normal control for serum osteocalcin detection. At different postoperative time points, bone mineral density detection, X-ray scanning, biomechanics measurement, histology and immunohistochemistry observations were conducted; serum estradiol, plasma cholesterol, serum osteocalcin and the ratio of uterine weight to body weight were detected. Results The bone mineral density of each group reached a peak 20 days after operation, showing a significant difference between groups A, B and C and group D (P lt; 0.05), and no significant differences among groups A, B and C (P gt; 0.05). On the 30th and 50th postoperative day, the maximum failure load and the maximum displacement of groups A, B andC were greater than those of group D (P lt; 0.05), but no significant differences among groups A, B and C were evident (P gt;0.05). On the 7th, 20th and 30th postoperative day, the X-ray score of fracture heal ing of groups A, B and C was greater than group D (P lt; 0.05); on the 50th postoperative day, there was significant difference between groups B and C and group D, and between group A and group C (Plt; 0.05), and no significant difference was evident between group B and group C (P gt; 0.05). The percentage of new bone formation in the fractured area of groups A, B and C was greater than that of group D on the 30th and 50th postoperative day (P lt; 0.05). For the type II collagen protein secretion in the fractured area, groups B and C were superior to group D on the 30th postoperative day (P lt; 0.05), and there was no significant difference between group A and group D (P gt; 0.05); no significant differences among four groups were evident on the 50th postoperative day (P gt; 0.05). On the 10th, 30th and 50th postoperative day, the serum osteocalcin of groups A, B, C and D was higher than that of normal control (P lt; 0.05), groups B and C were higher than group D (P lt; 0.05), and there was no significant difference between groups A, B and C, and between group A and group D (P gt; 0.05). For the plasma cholesterol, on the 30th postoperative day, no significant change was detected in each group (P gt; 0.05); on the 50th postoperative day, obvious decrease was observed in groups A, B and C, showing a significant difference compared with group D (P lt; 0.05). On the 30th and 50th postoperative day, there was significant difference between groups B and C and group D in serum estradiol (P lt; 0.05), and no significant differences were evident among other groups (P gt; 0.05). On the 30th and 50th postoperative day, the ratio of uterine weight to body weight in groups B and C was less than that of group D (P lt; 0.05), and no significant difference was evident between group A and group C (P gt; 0.05). Conclusion Oral administration of 7.5 mg/ (kg• d) RLX can promote the fracture heal ing of rabbit radius defect models safely and effectively.
Objective To study repair of osteochondral defects by using composite of autologous BMSCs and chitosan/HAP (CS/HAP) bilayered scaffold in rabbits and its feasibil ity as osteochondral tissue engineering scaffolds. Methods CS/HAP bilayered scaffolds were produced with CS and HAP using a lyophil ization and sintering method. The pore size of the scaffold was observed by scanning electron microscopy (SEM). Anhydrous ethanol substitution method determined its porosity. BMSCs were isolated from bone marrow and cultured by general bone marrow methods. Both CD44 and CD45 on the BMSCs surface were detected with immunocytochemistry to identify BMSCs. Cell-scaffold complex was made with BMSCs as seed cells and CS/HAP bilayered scaffold as carrier by fibrin glue planting technique. The distribution ofBMSCs in CS/HAP scaffold was tested by SEM. The osteochondral defect (4 mm in diameter and 3 mm in height) model was made in the right knee joint of 36 Japanese white rabbits, which were randomly divided into 3 groups. Defects were repaired with CS/HAP and BMSCs composite ( group A, n=12) and with CS/HAP implants (group B, n=12); defects were not treated as a control (group C, n=12). Histological evaluation and gross observation were carried out at 6 weeks (n=6 in each group) and 12 weeks (n=6 in each group) postoperatively. Semi-quantitative histomorphological analysis was done to evaluate the repair cartilage tissue according to the modified Wakitani grading scale. Results CS/HAP bilayered scaffold possessed a porosity of 76.00% ± 5.01% and pore size of 200-400 μm (mean 300 μm ) in CS layer, and 72.00% ± 4.23% and 200-500 μm (mean 350 μm) in HAP layer, respectively. BMSCs formed colonies within 10-14 days. Immunocytochemistry results showed BMSCs had positive CD44 expression and negative CD45 expression. At 6 and 12 weeks after operation, gross and histological observation showed that the cartilage defects were fully filled with regenerated tissue, but bone defects were partially repaired in group A; the cartilage and bone defects were partially filled with regenerated tissue in group B and group C. The modified Wakitani grading scale were 5.17 ± 1.17 and 3.20 ± 0.75 in group A, 9.00 ± 0.63 and 6.00 ± 0.89 in group B, and 10.00 ± 0.89 and 9.60 ± 0.82 in group C at 6 weeks and 12 weeks postoperatively, respectively; showing significant differences between group A and groups B, C (P lt; 0.05). Conclusion The novel CS/HAP bilayered scaffold possesses porous structure and will possibly become a newbiomaterial of osteochondral tissue engineering.
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）
In this paper,the changes of activities of enzymes relating toenergy metabolism in rabbit's retina during acute ocular hypertension were observed.The activities of succinate dehydrogenase and adenosine triphosphatase were foud to be reduced,while the activities of the lactatic dehydrognease and glucose-6-phosphatase increased.The results reveal the disturbance of metabolism of energy in retina undergone acute ocular hypertension,and suggest that this might be the underlying factors relating to the defects of the functions and structures of the retina. （Chin J Ocul Fundus Dis,1993,9:141-144）