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.
Objective To investigate an improved large vascular reconstruction method in the canine liver transplantation and see whether it can shorten the anheptic time and thus reduce the harmful effects during the anhepatic phase. Methods Thirty-two mongrel dogs were enrolled and divided into two groups randomly:the donor group (n=16) and the acceptorgroup(n=16). The dogs in the acceptor group were divided into two groups, according to the different reconstruction methods: Group A using the magnetic rings for a large vein reconstruction in the canine liver transplantation (n=10), and Group B using a handsewing large vein reconstruction in the canine liver transplantation (n=6). The operation time, hemodymics change, anastomosis site, and survival were observed. Results The operation time was as follows: In Group A, the total operation time, the inferior vena cava anastomosistime, and the anheptic phase time were significantly shorter than those in Group B (3.24±0.49 h vs 4.12±0.51 h，5.89±2.27 min vs 28.33±6.04 min，3.89±0.73 min vs 12.16±3.72 min),with a significant difference between the two groups (Plt;0.01). The haemodymics changes were as follows: In Group A, MAP dropped during the anhepatic phase, but it soon recovered after reperfusion，and there was only 730.56±150.56 ml of fluid including the donor blood that needed to be transfused, with no pressor agent required. In Group B, blood pressure dropped during the anhepatic phase，but it slowly recovered，and there was 2241.67±390.78 ml of fluid. In Group A, all the stomas had no errhysis, twistor thrombus. The twisted stomas could be corrected by the revolving of the magnetic rings. The endangium at the site of anastomosis was smooth. In Group B, most of the stomas had errthysis. In Group A, 3 dogs survived for more than 7 days, 6dogs survived for 3-6 days, and 1 dog survived for only 12 hours. In Group B, 2 dogs survived for 3-6 days, 3 dogs survived for 1-2 days, and 1 dog survivedfor only 12 hours. Conclusion Using the magnetic rings for a large vascular reconstruction in the canine liver transplantation is an improvedmethod, which can simplify the anastomosis procedures and significantly shortenthe anheptic phase time. However, the magnetic rings have to be placed in the abdomen, so this method remains to be further improved.
Objective To explore the construction of a canine model of vascularized allogeneic spinal cord transplantation (vASCT) and preliminarily evaluate its therapeutic efficacy for spinal cord injury (SCI). Methods Sixteen female Beagle dogs aged 8-12 months were randomly selected, with 8 dogs serving as donors for the harvesting of spinal cord tissue with a vascular pedicle [dorsal intercostal artery (DIA) at the T10 level and accompanying vein]. The remaining 8 dogs underwent a 1.5-cm-length spinal cord defect at the T10 level, followed by transplantation of the donor spinal cord tissue for repair. Polyethylene glycol (PEG) was applied to both ends to spinal cord graft; then, using a random number table method, the dogs were divided into an experimental group (n=4) and a control group (n=4). The experimental group received immunosuppressive intervention with oral tacrolimus [0.1 mg/(kg?d)] postoperatively, while the control group received no treatment. The operation time and ischemia-reperfusion time of two groups were recorded. The recovery of hind limb function was estimated by Olby score within 2 months after operation; the motor evoked potentials (MEP) was measured through neuroelectrophysiological examination, and the spinal cord integrity was observed through MRI. ResultsThere was no significant difference in the operation time and ischemia-reperfusion time between the two groups (P>0.05). All dogs survived until the completion of the experiment. Within 2 months after operation, all dogs in the control group failed to regain the movement function of hind limbs, and Olby scores were all 0. In the experimental group, the movement and weight-bearing, as well as walking abilities of the hind limbs gradually recovered, and the Olby scores also showed a gradually increasing trend. There was a significant difference between the two groups from 3 to 8 weeks after operation (P<0.05). Neuroelectrophysiological examination indicated that the electrical signals of the experimental group passed through the transplanted area, and the latency was shortened compared to that at 1 month after operation (P<0.05), showing continuous improvement, but the amplitude did not show significant improvement (P>0.05). The control group was unable to detect any MEP changes after operation. MRI examination showed that the transplanted spinal cord in the experimental group survived and had good continuity with normal spinal cord tissue, while no relevant change was observed in the control group. ConclusionThe vASCT model of dogs was successfully constructed. This surgical procedure can restore the continuity of the spinal cord. The combination of tacrolimus anti-immunity is a key factor for the success of transplantation.
Objective To explore an effective method of culturing the canine bladder smooth muscle cells, observe the morphological characteristics of the bladder smooth muscle cells growing on acellular small intestinal submucosa（SIS） and offer an experimental basis for reconstruction of the bladder smooth muscle structure by the tissue engineering techniques. Methods The enzymetreatment method and the explant method were respectively used to isolate and harvest the canine bladder smooth muscle cells, and then a primary culture of these cells was performed. The canine bladder smooth musclecells were seeded on the SIS scaffold, and the composite of the bladder smooth muscle cells and the SIS scaffold were co cultured for a further observation. At 5,7 and 9 days of the co culture, the specimens were taken; the bladder smooth muscle cells growing on the SIS scaffold were observed by the hematoxylin staining, the HE staining, and the scanning electron microscopy. The composite of the bladder smooth muscle cells on the SIS scaffold was used as the experimental group, and the bladder smooth muscle cells with no SIS were used as the control group. In each group, 9 holes were chosen for the seeded bladder smooth muscle cells, and then the cells were collected at 3, 5 and 7 days for the cell counting after the enzyme treatment. Morphological characteristics of the cells were observed under the phase contrast microscope and the transmission electron microscope. Expression of the cell specific marker protein was assessed by the immunohistochemical examinaiton. The proliferation of the cells was assessed by the cell counting after the seeding on the SIS scaffold. Results The primary bladder smooth muscle cells that had been harvested by the enzyme treatment method were rapidly proliferated, and the cells had good morphological characteristics. After the primary culture in vitrofor 5 days, the bladder smooth muscle cells grew in confluence. When the bladder smooth muscle cells were seeded by the explant method, a small amount of the spindleshaped bladder smooth muscle cells emigrated from the explant at 3 days. The cells were characterized by the welldeveloped actin filaments inthe cytoplasm and the dense patches in the cell membrane under the transmissionelectron microscope. The immunohistochemical staining showed the canine bladdersmooth muscle cells with positive reacting α actin antibodies. The bladder smooth muscle cells adhered to the surface of the SIS scaffold, growing and proliferating there. After the culture in vitro for 5 days, the smooth muscle cells covered all the surface of the scaffold, showing a singlelayer cellular structure. The cell counts at 3, 5 and 7 days in the experimental group were（16.85±0.79）×105，（39.74±2.16）×105 and （37.15±2.02）×105, respectively. Thecell counts in the control group were（19.43±0.54）×105，（34.50±1.85）×105 and （33.07±1.31）×105, respectively. There was a significant difference between the two groups at 5 days （P＜0.05）. ConclusionWith the enzyme treatment method, the primarily cultured canine bladder smooth muscle cells can produce a great amount of good and active cells in vitro. The acellular SIS can offer an excellent bio scaffold to support the bladder smooth muscle cells to adhere and grow, which has provided the technical foundation for a further experiment on the tissue engineered bladder reconstruction.
This study was to build a canine portal hypertension model by intra-portal administration of high polymer material polyurethane and organic solvent tetrahydrofuran mixed solutions in order to evaluate the effectiveness of the model. Twelve local crossbreed dogs were selected randomly, with intra-portal administration of 8% (weight/volume) polyurethane-tetrahydrofuran solutions through an incision in the upper abdomen to build the portal hypertension model. We measured the portal vein pressure before modeling, during modeling, and four-, eight-, and twelve-weeks after modeling, respectively. Then we evaluated the effectiveness of the model comparing values of data with those data obtained before modeling started, which were regarded as the normal values. The results showed that the portal vein pressure rose by 2.5 times after the solution administrated instantly as much as that before modeling, and maintained at 1.5 times after 4 weeks. This method presents an easy operation, low animal mortality and reliable model of portal hypertension. Its less abdominal adhesions and its ability in keeping normal anatomic structure specially make it suit for surgical research of portal hypertension.
ObjectiveTo verify the feasibility of a self-designed magnetic anchoring and traction device (MATD) for assisting two-port video-assisted thoracoscopic esophagectomy.MethodsThree Beagle dogs were selected as animal models with age ranging from 1-6 years and weight ranging from 8-12 kg, and they underwent two-port video-assisted thoracoscopic esophagectomy after general anesthesia. We used the MATD to retract the esophagus to different directions, which assisted mobilizing esophagus, detecting the nerves along esophagus and dissecting paraesophagus lymph nodes. The operation time, blood loss and feasibility of the MATD were recorded.ResultsWith the aid of the MATD, we successfully retracted and mobilized the esophagus, detected the nerves and dissected the lymph nodes in three Beagle dog models. During the operation, the MATD provided sufficient and steady traction of esophagus to achieve a good exposure of the operative field, effectively decreasing the interference between working instruments. The MATD worked well. The mean operation time was 30 min, and the mean intraoperative blood loss was about 10 mL.ConclusionIt is effective to use the MATD to assist retracting esophagus during video-assisted thoracoscopic esophagectomy. The magnetic anchoring and traction technique can assist to expose the surgical field, decrease the interference between the working instruments and have the potential clinical application.
Objective To discuss the way of animal model building of hepaticocholedochostomy(HC) and hepaticojejunostomy(HJ) and to compare the short-term effect. Metheds Twenty-nine dogs were divided randomly into control group(n=5) and the experimental group (stenosis of left hepatic duct, n=24). After 7 weeksof stenosis of left hepatic duct,24 dogs in the experimental group were divided randomly into HC subgroup (n=12) and HJ subgroup (n=12) .The operation time and the blood loss during operation were recorded and the hepatic function was detected.Results The diameter of left hepatic duct was significantly expended after 7 week’s stenosis. Hepaticocholedochostomy took shorter time and lost less blood than hepaticojejunostomy. The dogs in HC subgroup lost less weight than thosein HJ subgroup. In HC and HJ subgroups, the mortality rates were 1/12 and 3/12;the infectious rates of incision were 3/12and 5/12 respectively. Serum levels of total bilirubin and transaminase increased significantly in the 7th week after stenosis of left hepatic duct compared with before stenosis of left hepatic duct. However, Serum levels of total bilirubin and transaminase restored to normallevels after 1 month of HC or HJ.Conclusion It is feasible to establish animal model of bile duct reconstruction on the basis of stricture of bile duct. The dogs undergoing hepaticocholedochostomy have less trauma, better results than the dogs undergoing hepaticojejunostomy. Both hepaticocholedochostomy and hepaticojejunostomy are able to relieve the obstruction of bile duct.
Objective To investigate the result of the transplantation of frozen canine phalangeal joint allografts perforated and incorporated with autogenic bone marrow. Methods A proximal interphalangeal joint defect of 1.5 cm was prepared at bilateral sides of twenty-four adult healthy out-bred dogs. Three different types of allografts were applied to repair the defects: fresh autogenic phalangeal joints (group A,n=16), frozen phalangeal joint allografts perforated and incorporated with fresh autogenic bone marrow(group B, n=16), and frozen phalangeal joint allografts(group C, n=16). Radiographic and histological study wereused to evaluate the survival of transplanted joints. The observation was done 1, 3, 6 and 12 months after operation respectively. Results Based on the radiographic and histological changes of the transplanted joints, the osteoarthropathy of transplanted canine phalangeal joints could be divided into 3 degrees: mild degeneration, moderate degeneration and severe degeneration. Mild degeneration was observed in group A from 3 to 12 months. Mild degeneration was also found in group B from 1 to 6 months, and the endochondral ossification was obvious within the drilled bony holes.However, some joints in group B underwent moderate degeneration 12 months after operation. Group C joints in the first month had moderate degeneration, which progressed to severe egeneration 3 months after operation. Conclusion Transplantation of frozen canine phalangeal joint allografts perforated and incorporated with autogenic bone marrow can effectively delay the degeneration of transplanted osteoarticular allografts at the early and middle stage.
