ObjectiveTo explore the method and feasibility of establishing patent ductus arteriosus (PDA) model in Bama miniature pig by using autologous jugular vein, and to provide a large animal model for the development of PDA occluder and the study of pulmonary hypertension associated with congenital heart disease. MethodsFive male Bama miniature pigs weighing about 45 kg were selected to gain the PDA model of the autogenous jugular vein, which was fixed by glutaraldehyde and anastomosed between the ascending aorta and the main pulmonary artery. The patency of PDA was confirmed by echocardiography and angiocardiography immediately and one week after the operation. Two animals were selected to undergo transcatheter closure of PDA via femoral vein 1 week after the operation, and the rest were euthanized to obtain PDA and lung tissue for pathological examination. ResultsThe PDA model was successfully established in all five animals with a success rate of 100.0%. Immediately and 1 week after the operation, echocardiography and angiography showed that PDA blood flow was unobstructed, and hematoxylin-eosin staining showed that PDA endothelialization was good. One week after the operation, two animals were successfully treated with transcatheter femoral vein occlusion. The pathological examination of lung tissue showed thickening of the intima and muscular layer of pulmonary arterioles, thickening of pulmonary interstitium and infiltration of neutrophils. ConclusionIt is safe and feasible to establish a large animal model of PDA by using autogenous jugular vein anastomosis between the ascending aorta and the main pulmonary artery. The model can be used for the development of PDA interventional occlusive devices and the pathophysiological study of congenital heart disease-related pulmonary hypertension.
ObjectiveTo investigate the safety and feasibility of domestic MP1000 robotic surgical system assisted thyroidectomy via submaxillary approach in porcine animal model. MethodThe thyroidectomy process assisted by the MP1000 robotic surgical system via submaxillary approach for a Bama pig in the 960th Hospital of the Joint Logistics Support Force was retrospectively analyzed. ResultsThe operation was performed as planned programme using the MP1000 robotic surgical system without opening, adding or lengthening the surgical incision. There was no mechanical problems during the MP1000 robotic surgical operation. The operative time was 53 min and the estimated intraoperative blood loss was 10 mL. There was no shaking of instruments and robotic arm during the operation, and the 3 surgical instruments cooperated skillfully, the establishment of surgical operation space successfully was completed, the thyroid blood vessels accurately and finely was dissected, and the separation, coagulation and cutting of blood vessels were smoothly completed. The recurrent laryngeal nerve and parathyroid gland were delicately dissected and protected. The carotid sheath, trachea, esophagus, and other important organs around the thyroid did not be damaged. The master-slave mapping frequency was high, and there was no delay sense during the operation. The lens resolution of MP1000 was 1 920×1 080, the surgical field of vision was clear, no visual field was defected and the visual field was stable and not shaking, light source front and intelligent adaptive temperature control system reduced the fogging of the lens, and the lens was scoured for 4 times during the operation. ConclusionAccording to the preliminary results of the experimental animal in this study, MP1000 robotic surgical system can successfully complete thyroidectomy via submaxillary approach in porcine animal model.
ObjectiveTo observe the effect of using tungsten drills to prepare mouse knee osteochondral injury model by comparing with the needle modeling method, in order to provide an appropriate animal modeling method for osteochondral injury research.MethodsA total of 75 two-month-old male C57BL/6 mice were randomly divided into 3 groups (n=25). Mice in groups A and B were used to prepare the right knee osteochondral injury models by using needles and tungsten drills, respectively; group C was sham-operation group. The general condition of the mice was observed after operation. The samples were taken at 1 day and 1, 2, 4, and 8 weeks after modeling, and HE staining was performed. The depth, width, and cross-sectional area of the injury site at 1 day in groups A and B were measured, and the percentage of the injury depth to the thickness of the articular cartilage (depth/thickness) was calculated. Toluidine blue staining and immunohistochemical staining for collagen type Ⅱ were performed at 8 weeks, and the International Cartilage Research Society (ICRS) score was used to evaluate the osteochondral healing in groups A and B.ResultsAll mice survived to the completion of the experiment. HE staining showed that group C had normal cartilage morphology. At 1 day after modeling, the injury in group A only broke through the cartilage layer and reached the subchondral bone without entering the bone marrow cavity; the injury in group B reached the bone marrow cavity. The depth, width, cross-sectional area, and depth/thickness of the injury in group A were significantly lower than those in group B (P<0.05). At 1, 2, 4, and 8 weeks after modeling, there was no obvious tissue filling in the injured part of group A, and no toluidine blue staining and expression of collagen type Ⅱ were observed at 8 weeks; while the injured part of group B was gradually filled with tissue, the toluidine blue staining and the expression of collagen type Ⅱ were seen at 8 weeks. At 8 weeks, the ICRS score of group A was 8.2±1.3, which was lower than that of group B (13.6±0.9), showing significant difference (t=?7.637, P=0.000).ConclusionThe tungsten drills can break through the subchondral bone layer and enter the bone marrow cavity, and the injury can heal spontaneously. Compared with the needle modeling method, it is a better method for modeling knee osteochondral injury in mice.
ObjectiveTo understand research progress of animal model of esophageal achalasia and discuss its pathogenesis briefly.Method Literatures about research progress of animal model of esophageal achalasia were reviewed. ResultsThe models of esophageal achalasia could been made in several ways, such as the obstruction model, the classic denervation model, and the increasingly popular gene model. These models were all based on the theory of the corresponding causes, with the processing of different factors, then completed the preparation of animal model. Conclusionsanimal model of esophageal achalasia goes through three stages: obstruction model, denervation model, and gene model. gene model of esophageal achalasia based on congenital theory could help us understand this disease better and make an ideal animal model, which could provide a reliable evidence for etiology study.
ObjectiveTo explore the feasibility of establishment of a artificial joint aseptic loosening mouse model by cobalt-chromium particles stimulation.MethodsTwenty-four 8-week-old male severe combined immunodeficient (SCID) mice were divided into experimental group (n=12) and control group (n=12). The titanium nail was inserted into the tibial medullary cavity of mouse in the two groups to simulate artificial joint prosthesis replacement. And the cobalt-chromium particles were injected into the tibial medullary cavity of mouse in experimental group. The survival of the mouse was observed after operation; the position of the titanium nail and the bone mineral density of proximal femur were observed by X-ray film, CT, and Micro-CT bone scanning; and the degree of dissolution of the bone tissue around the tibia was detected by biomechanical test and histological staining.ResultsTwo mice in experimental group died, and the rest of the mice survived until the experiment was completed. Postoperative imaging examination showed that there was no obvious displacement of titanium nails in control group, and there were new callus around the titanium nails. In experimental group, there was obvious osteolysis around the titanium nails. The bone mineral density of the proximal tibia was 91.25%±0.67%, and the maximum shear force at the tibial nail-bone interface was (5.93±0.85) N in experimental group, which were significantly lower than those in control group [102.07%±1.87% and (16.76±3.09) N] (t=5.462, P=0.041; t=3.760, P=0.046). Histological observation showed that a large number of inflammatory cells could be seen around the titanium nails in experimental group, while there was no inflammatory cells, and obvious bone tissue formation was observed in control group.ConclusionThe artificial joint aseptic loosening mouse model can be successfully established by cobalt-chromium particles stimulation.
This study sought to investigate the in vivo antiviral effect of amantadine (AM) and biphenyl dimethyl dicarboxylate (DDB) on hepatitis B virus (HBV) in HBV replication mice. HBV replication-competent plasmid was transferred into male BALB/c mice by using hydrodynamics-based in vivo transfection procedure to develop HBV replication mouse model. The model mice were matched by body weigh, age and serum levels of hepatitis B e antigen (HBeAg) and were divided into four groups:AM group, DDB group, AM+DDB group and NS group, with the last one as control, and the mice of each group were administered corresponding agent orally twice a day, in a medication course lasting 3 d. On the third day, the mice were sacrificed 4-6 h after the last oral intake. HBV DNA replication intermediates in liver were analyzed by Southern blot hybridization. The serum hepatitis B surface antigen (HBsAg) and HBeAg were detected by enzyme linked immunosorbent assay (ELISA). Compared to the animals in the control group, HBV DNA replication intermediates in liver and HBsAg and HBeAg in serum from the AM and AM plus DDB group of mice decreased, and there was no difference between these two groups of mice. The levels of HBV DNA intermediate from liver and the serum HBsAg and HBeAg between the control and DDB group, however, were not obviously different. In conclusion, the inhibition effect of AM on HBV was detected, but treatment with DDB for 3 days did not influence the viral replication and expression of HBV in the HBV replication mice.
ObjectiveTo research the procedure for creating an animal model of mitral regurgitation by implanting a device through the apical artificial chordae tendineae, and to assess the stability and dependability of the device. MethodsTwelve large white swines were employed in the experiments. Through a tiny hole in the apex of the heart, the artificial chordae tendineae of the mitral valve was inserted under the guidance of transcardiac ultrasonography. Before, immediately after, and one and three months after surgery, cardiac ultrasonography signs were noted. Results All models were successfully established. During the operation and the follow-up, no swines died. Immediately after surgery, the mitral valve experienced moderate regurgitation. Compared with preoperation, there was a variable increase in the amount of regurgitation and the values of heart diameters at a 3-month follow-up (P<0.05). ConclusionIn off-pump, the technique of pulling the mitral valve leaflets with chordae tendineae implanted transapically under ultrasound guidance can stably and consistently create an animal model of mitral regurgitation.
The incidence of acute kidney injury (AKI) has increased rapidly in recent years. The causes of AKI are complex and diverse, and there is no effective treatment strategy. Reliable and stable animal models and in vitro models play an important role in the development and prevention of AKI. Focusing on rodent models and in vitro models, this review summarizes AKI models induced by ischemia, nephrotoxic drugs and urinary tract obstruction from three levels of prerenal, intrinsic renal and postrenal AKI.
ObjectiveTo establish a model of tracheomalacia in beagle dogs.MethodsSix healthy male beagles were selected with a weight of 12-15 kg and age of 12-18 months. The dog was placed in supine position after being anesthetized. Then midline incision was performed on dogs' cervical skin and main trachea was dissected. Six continuous cartilage rings separated from the tracheal wall were removed. Finally, the endotracheal mucosal was examined and the wound was sutured layer by layer. Different degrees of cartilage were removed to simulate different degrees of tracheomalacia. The beagle dogs were classified into two groups (n=3 in each group): a mild tracheomalacia (MTM) group (part of the cartilage near the trachea membrane was retained) and a severe tracheomalacia (STM) group (cartilage was removed as much as possible).ResultsThe dogs in the MTM group survived for a long time after the operation, showing symptoms of airway stenosis such as wheezing and coughing. The dogs were killed at postoperative week 2, and the pathological examination was performed. In the STM group, severe asphyxia occurred in the experimental animals after tracheal intubation removed, and all dogs died within 1 hour after surgery. Postoperative bronchoscopy revealed that the trachea of the MTM group dogs collapsed in the phase of inhalation, but it could maintain a certain patency. The trachea of the STM group dogs collapsed completely in the phase of inhalation. Postoperative X-ray showed that the diameter of the airway in the MTM group was reduced and trachea did not completely collapse. In the STM group, the trachea collapsed completely at the cartilage removed segment. Pathological examination showed that the cartilage in the MTM group was partially removed and tracheomalacia was obvious in the cartilage removed segment. In the STM group, most of the cartilage was removed with only few cartilages left.ConclusionThe clinical symptoms of tracheomalacia in different degrees can be simulated and repeatable. Animal models can be established by controlling the degree of removal of tracheal cartilage ring in dogs. This method provides a simple, repeatable and standardized large animal model for the treatment and transformation of tracheomalacia.
ObjectiveTo explore the feasibility of goat tricuspid regurgitation (TR) model by one chordae tendineae cutter via right anterior-lateral minimal incision.MethodsTR model was established in 6 goats with a self-made tricuspid valve chordae tendineae cutter. The goats were placed in a left lateral position and procedure was performed via a right anterior-lateral minimal thoracotomy in the fourth intercostal. Under the guidance of transesophageal ultrasound and digital subtraction angiography, the chordae tendineae of anterior leaflet was cut until moderate to severe regurgitation was confirmed. Echocardiography and laboratory examinations were performed preoperatively, immediately and 3 months after surgery. Additionally, all goats were sacrificed to clarify pathological evaluation.ResultsTR was successfully established in 6 goats. The right atrium pressure increased significantly immediately after surgery (P<0.05). During a follow-up of 3 months, the progression of TR was aggravated (P<0.05), and the annular diameter increased from 2.15±0.23 cm to 2.65±0.20 cm. Overall, there was no statistically significant change in transvalvular gradient and velocity between preoperation and postoperation. Laboratory test results showed no abnormalities between preoperation and postoperation. Autopsy evaluation demonstrated obvioue chordae tendineae transection of the anterior leaflet.ConclusionIt is feasible to establish TR model via a right minimal anterior lateral thoracotomy in the fourth intercostal space. This novel TR goats model will allow investigation of transcatheter interventional device and serve as a chronic model in the future.