目的 建立犬开放性气胸海水浸泡的实验模型 ,探讨实验动物早期死亡原因。 方法 2 0条健康成年杂种犬随机分为两组。对照组 :实验动物受伤后直接观察 ;实验组 :动物受伤后置入人工配制的海水中。监测血流动力学、呼吸、血液渗透压、血液电解质、动脉血气变化以及肺部病理改变。 结果 实验组死亡率明显高于对照组 ,平均生存时间为 45分钟。实验组经海水浸泡后有急性呼吸和循环功能衰竭、严重电解质平衡紊乱、高渗血症、重度肺损伤以及严重代谢性和呼吸性酸中毒。 结论 开放性气胸后海水浸泡可引起一系列严重的病理生理变化 ,其结果是导致实验动物早期死亡的重要原因。
Objective To make a comparison for the change of maximum tensile intensity and stiffness of a whole implant that is placed into bone tunnel with various lengths tendon, by using beagle dog’s autogenous flexor tendons to reconstruct anterior cruciate l igament (ACL). Methods Sixty male beagle dogs were included in the experiment (weighting 13-16 kg). Three dogs were used for intact flexor tendon of both knees (normal control group), 3 dogs for the intact ACL andfemur-graft-tibia complex (auto control group) and 54 dogs (108 knees) for models of reconstructed ACL (6 experimentalgroups according to different lengths of tendon: 5, 9, 13, 17, 21 and 25 mm in the bone tunnel). The tensile intensity and stiffness were measured after 45, 90 and 180 days separately after operation. Results In the normal control group, the maximum tensile intensity of the intact flexor tendon was (564.15 ± 36.18) N, the stiffness was (59.89 ± 4.28) N/ mm. In the auto control group, the maximum tensile intensity of the intact ACL was (684.75 ± 48.10) N, the stiffness was (74.34 ± 6.99) N/ mm, all ruptured through the intra-articular portion of the graft. The maximum tensile intensity of femur-graft-tibia complex in the auto control group was (301.92 ± 15.04) N, the stiffness was (31.35 ± 1.97) N/mm. After 45 days of operation, all failure occurred at the tibial or femoral insertion site. After 90 days of operation, 24 of the breakpoints were scattered in tendon-bone junction, 12 (3 in 17 mm group, 5 in 21 mm group, 4 in 25 mm group) ruptured through the intra-articular portion. After 180 days of the operation, all breakpoints were distributed inside joint of the implant. The maximum tensile intensity and the stiffness were ber in 17, 21 and 25 mm groups than in 5, 9 and 13 mm groups after operation (P lt; 0.05). Conclusion Tendon with 17 mm length, which will be implanted into bone tunnel, is an appl icable index, in reconstruction of ACL by autogenous tendons.
In order to study the influence of biliary tract obstruction on enteromicroflora,we ligate the canine biliary tract to observe the acrobic and anerobic bacteria in the duodenum and ileum at intervals of post-ligation(the 10th,20th,30th days),and to study the pathogenesis and ultramicroscopic of the ileal mucosa at the same intervals.The results showed that:the population and species of enteroflora in small intestine gradually increased after biliary obstruction.Bacteria(especialy E.coli) ascended to the upper part of small intestine,from their normal habitant of lower part of small intestine.Therefore the radio of general aerobia and E.coli risen obviously in duodenum.The longer the obstruction,the more pathologic changes were observed in ileal mucosa.such as edema,leukocytes infiltration and destruction of epithelial villi.All of those changed may be the causative factor of biliary tract infection.So that,in the programs of preventing enterogenic infection at the state of biliary tract obstruction,the protection and adjusting of normal enteroflora should be adventently considered.
Objective To observe the complication after embolizing the bilateral internal il iac arteries and the median sacral artery of dogs by different combinations and embolization levels with gelfoam particle, and to provide a reference for safety appl ication of gelfoam in cl inic. Methods Sixteen common grade adult healthy dogs (weighing 10-13 kg, 14 males and 2females) were randomly divided into 5 groups. Under the monitoring of digital subtraction angiography (DSA), the embolization was performed with gelfoam particle (diameter, 50-150 μm) in bilateral internal il iac arteries and the main branch of the median sacral artery (group A, n=3), in bilateral internal il iac arteries and the first branch of the median sacral artery (group B, n=3), in the main branch of bilateral internal il iac arteries (group C, n=3), in the unilateral internal il iac artery and the main branch of the median sacral artery (group D, n=4), and in the main branch of unilateral internal il iac artery (group E, n=3). Under the DSA, the anatomic relationships of the abdominal aorta, bilateral external il iac arteries, bilateral internal il iac arteries, and median sacral artery were observed before embol ization. The survival dogs were observed and the specimens of bladder, rectum, sciatic nerve, and gluteal muscles were harvested for the general and histological observations at 3 days after embolization. Results In dogs, there was no common il iac artery; bilateral external il iac arteries originated from the abdominal aorta and the starting of the median sacral artery had variation. Seven dogs (3 in group A, 3 in group C, and 1 in group D) died within 2 days after embolization, and the others survived to the end of the experiment. In the dead dogs of groups A, C, and D, the darkening and necrosis of the rectum were observed; the bladder presented lamellar obfuscation and focal hemorrhage and edema; and the median urinary volume in bladder was 270.6 mL. In survival dogs, no obvious change was observed in the rectum; the bladder only manifested l ight edema; and the median urinary volume in bladder was 137.0, 220.5, and 28.0 mL, respectively in groups B, D, and E.The rectum and bladder of dead dogs in groups A, C, and D manifested the disrupted cells, generous inflammatory cells infiltration, and desquamation of epithel ial cells; the rectum and bladder of survival dogs in groups B, D, and E manifested l ight inflammatory cells infiltration and edema; the embol ized artery mainly focused on the arterioles whose diameter was 100-200 μm. The sciatic nerve and gluteal muscles of each group had no obvious change except for l ight edema. Conclusion When the internal il iac artery and median sacral artery are embol ized with gelfoam particle with a diameter of 50-150 μm, to ensure the safeness of pelvic organs, the embol ized artery can not exceed the first branch when the 3 arteries are embol ized at the same time, or reserve at least unilateral internal il iac artery when embol ized to the trunk , or it will result in pelvic organ necrosis and perforation.
【Abstract】 Objective To investigate the possibil ity of BMSCs seeded into collagen Ⅰ -glycosaminoglycan (CG)matrices to form the tissue engineered cartilage through chondrocyte inducing culture. Methods Bone marrow aspirate of dogs was cultured and expanded to the 3rd passage. BMSCs were harvested and seeded into the dehydrothemal treatment (DHT)cross-l inked CG matrices at 1×106 cells per 9 mm diameter sample. The samples were divided into experimental group and control group. In the experimental group, chondrogenic differentiation was achieved by the induction media for 2 weeks. Medium was changed every other day in both experimental group and control group. The formation of cartilage was assessed by HE staining and collagen Ⅱ immunohistochemical staining. Results The examinations under the inverted phase contrast microscopeindicated the 2nd and 3nd passage BMSCs had the similar morphology. HE staining showed the BMSCs in the experimental group appeared polygon or irregular morphology in the CG matrices, while BMSCs in the control group appeared fibroblast-l ike spindle or round morphology in the CG matrices. Extracellular matrix could be found around cells in the experimental group. Two weeks after seeded, the cells grew in the CG matrices, and positive collagen Ⅱ staining appeared around the cells in the experimentalgroup. There was no positive collagen Ⅱ staining appeared in the control group. Conclusion It is demonstrated that BMSCs seeded CG matrices can be induced toward cartilage by induction media.
Abstract: Objective To observe the changes in morphology, structure, and ventricular function of infarct heart after bone marrow mononuclear cells (BMMNC) implantation. Methods Twenty-four dogs were divided into four groups with random number table, acute myocardial infarction (AM I) control group , AM I-BMMNC group , old myocardial infarct ion (OMI) control group and OM I-BMMNC group , 6 dogs each group. Autologous BMMNC were injected into infarct and peri-infarct myocardium fo r transplantation in AM I-BMMNC group and OM I-BMMNC group. The same volume of no-cells phosphate buffered solution (PBS) was injected into the myocardium in AM Icontrol group and OM I-control group. Before and at six weeks of cell t ransplantation, ult rasonic cardiography (UCG) were performed to observe the change of heart morphology and function, then the heart was harvested for morphological and histological study. Results U CG showed that left ventricular end diastolic dimension (LV EDD) , left ventricular end diastolic volume (LVEDV ) , the thickness of left ventricular postwall (LVPW ) in AM I-BMMNC group were significantly less than those in AM I-control group (32. 5±5. 1mm vs. 36. 6±3. 4mm , 46. 7±12. 1m l vs. 57. 5±10. 1m l, 6. 2±0. 6mm vs. 6. 9±0. 9mm; P lt; 0. 05). LVEDD, LVEDV , LVPW in OM I-BMMNC group were significantly less than those in OM I-control group (32. 8±4. 2 mm vs. 36. 8±4. 4mm , 48. 2±12. 9m l vs. 60.6±16.5m l, 7. 0±0. 4mm vs. 7. 3±0. 5mm; P lt; 0. 05). The value of eject fraction (EF) in OM I-BMMNC group were significantly higher than that in OM I-control group (53. 3% ±10. 3% vs. 44. 7%±10. 1% ). Compared with their control group in morphological measurement, the increase of infarct region thickness (7. 0 ± 1. 9mm vs. 5. 0 ±2.0mm , 6.0±0. 6mm vs. 4. 0±0. 5mm; P lt; 0. 05) and the reduction of infarct region length (25. 5±5. 2mm vs. 32. 1±612mm , 33. 6±5. 5mm vs. 39. 0±3. 2mm , P lt; 0. 05) were observed after transplantation in AM I-BMMNC group and OM I-BMMNC group, no ventricular aneurysm was found in AM I-BMMNC group, and the ratio between long axis and minor axis circumference of left ventricle increased in OM I-BMMNC group (0. 581±0. 013 vs. 0. 566±0.015; P lt; 0. 05). Both in AM I-BMMNC group and OM I-BMMNC group, fluorescence expressed in transplantation region was observed, the morphology of most nuclei with fluorescencew as irregular, and the differentiated cardiocyte with fluorescence was not found in myocardium after transplantation. The histological examination showed more neovascularization after transp lantation both in AMI and in OM I, and significant lymphocyte infiltration in AM I-BMMNC group. Conclusion BMMNC implantation into infarct myocardium both in AMI and OMI have a beneficial effect, which can attenuate deleterious ventricular remodeling in morphology and st ructure, and improve neovascularization in histology, and improve the heart function.
Objective-To apply self-pulmonary tissue flap to reconstruct esophagus directly or with alloy stent in this research. Methods Twenty-four dogs were divided into two groups, middle bronchus was ligated to prepare pulmonaryflap and incised, a 4 to 6 cm long and 1/2 to 2/3 perimeter defect was made in esophageal wall. Esophagus defect was repaired only with pulmonary flap (experimental group) and with pulmonary flap having self-expanded stent inside (control group). The gross appearance, histological apearance and barium X-ray films were observed at 2,4,6,8,10 and 12 weeks after operation. Results Two dogs died of anatomotic leak in experimental group, three dogs died of anatomotic leak and two dogs died of perforation of ulcer in control group. The growth of esophagus epithelium was observed from periphery area to central area after 8 to 10 weeks of operation. In pulmonary flap mass fibrous tissue proliferated and fibroblasts were active, but no necrosis occurred. Barium X-ray ofregenerated esophagus showed that mild stenosis and weakened peristalisis were observed in the middle of resophagus replacement, and that no obstruction, leakage, and dilation above anastomotic stoma occurred. Conclusion Pulmonary tissue flap can well support the mucosa crawl in the defect of esophagus. It is necessary to find a more suitable and satisfied stent for repairing segmental defect.
In order to study rheologic property of bile flow between gallbladder and biliary duct during biliary obstruction,we made a model of complete biliary obstruction(CBO)in dogs.The results showed that:①The behavior of bile flow between gallbladder and biliary duct in noemal dogs belonged to Casson flow;②When the duration of CBO prolonged,the behavior of bile flow between gallbladder and biliary tract in the CBO dogs still belonged to Casson flow.The changes of yield stress and apparent viscosity at high or low shear rate in bile flow of the biliary duct were similar to that in bile flow of the gallbladder.
To evaluate the implantation effect of artificial vascular grafts with recombinant fibrinolytic enzyme factor II (rF II)-immobil ized lumina in animal test. Methods Four mm internal diameter (ID) polyurethane (PU) artificial vascular grafts were prepared by di pping and leaching method. The micro-pore size and morphology of the graft walls were observed by SEM. The graft lumina were immobil ized with rF II. Twenty hybrid male dogs [weighing (20 ± 1) kg] were used for animal model of carotid artery defect and were randomly divided into 3 groups: rF II -immobil ized PU group, no rF II -immobil ized PU group and expanded polytetrafluoroethylene (ePTFE) group. The vascular grafts were implanted for repairing injured segments of carotid artery in dogs. The general health state of animals was recorded. At 30 days and 60 days,the patency rate of every group was calculated. At 60 days IDs were measured, cell prol iferation in neointima was inspected by l ight microscope, morphology on neointima was observed by SEM. Results The ID of the PU vascular grafts was (3.74 ± 0.06) mm, wall thickness was 0.4-0.6 mm, the wall density was 0.25 g/cm3, the porosity was 79.8%, racical compl iance was 8.57%/100 mmHg. In the wall, micropores were well distributed and opened-pores structure was observed. Pore size was (140 ± 41) μm in the outside layer, pore size was (100 ± 3) μm in the inside layer, thickness ratio of outside / inside layers was 2 ∶ 1, the pore size was (40 ± 16) μm on the lumina surface. After operation the wounds on neck healed, all the animals survived and had no compl ication. At 30 days and 60 days after implantation, the patency rate for rF II -immobil ized PU group were 100% and 66.7%, for no rF II -immobil ized PU group were 66.7% and 33.3%, and for ePTFE group were 67.7% and 0 respectively, but at 60 days there were thrombosis at anastamotic sites of some grafts occluded. Before operation the IDs for rF II-immobil ized PU group, no rF II -immobil ized PU group and ePTFE group were (3.74 ± 0.06), (3.74 ± 0.06) and (4.00 ± 0.03) mm, at 60 days after operation the IDs were (4.51 ± 0.05), (4.31 ± 0.24) and (4.43 ± 0.12) mm respectively, showing no statistically significant differences between 3 groups (P gt; 0.05). Histological inspection indicated that at 15 days a layer of plasma protein deposited on the lumina, at 30 days some cells adhered to the lumina, at 60 days neointima could be observed on the lumina. Thickness of the neointima became larger with implantation time. At 60 days neointima thickness at proximal end, middle site and distal end ofgraft were (560 ± 22), (78 ± 5) and (323 ± 31) μm respectively for rF II -immobil ized PU group. The results of SEM showed that neointima surface consisted of flat and long cells which long axes ranged with blood flow direction and was similar to lumina morphology of carotid artery of dog. Conclusion Immobil ization of rF II to lumina of grafts could enhance fibrinolytic activity and inhibited formation of thrombo-embol ia which led to an increase in patency rate after implantation.
To evaluate the effect of technique combination of implant-retented titanium lattice with decalcified dental matrix (DDM) implanting. Methods Six healthy male dogs (weighing of 10-20 kg) were randomly divided into 3 groups. All the premolars were extracted on both sides of the jaw in dogs. After 2 weeks, titanium lattice and implant were implanted in the maxillary premolar region with DDM on one side (experimental group), but without on the other side (control group) of each dog. After 4, 9 and 14 weeks, respectively, 2 animals were individually killed each time, and the samples wereevaluated by general observation, X-ray examination, histological observation and histomorphometric analyses. Results General observation: Among the 6 dogs, there was no postoperative infection or death. The X-ray examination showed that the bone density of the experimental group was greater than the control group at 4 and 9 weeks, and had no significant difference as to the vicinity bone at 14 weeks. On the other hand, the density of the control group was very low under the titanium lattice and around the implant. The experimental group revealed a ridge augment of (1.93 ± 0.24) mm, and control group (-1.02 ± 1.20) mm (P lt; 0.05). Developed bone sponge could be found after 14 weeks. Histological observation showed that in the experimental group, the DDM surface was nearly absorbed at 4 weeks. A few new bones were formed at 9 weeks. The whole DDM was absorbed; the trabecular bone was thick and arranged regularly; and the intergradations of implant were observed at 14 weeks. In the control group, there were some inflammatory fibers around the neck of implant at 4 weeks. The inflammatory condition extended to the root of implant and the titanium lattice at 9 weeks. There was no newly-formed bone under the titanium lattice at 14 weeks. Histomorphometric analyses showed that the implant contact bone ratio approached 1 ∶ 1, and showed no significant difference between the new bone fragment and former bone fragment in the experimental group. Conclusion This augmentation of alveolar ridge evaluated by the study is appl icable, but further study is necessary.