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 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.
ObjectiveTo summarize the application research progress of animal models of hepatocellular carcinoma at home and abroad in recent years. MethodThe relevant literature on animal models of hepatocellular carcinoma at home and abroad in recent years was reviewed. ResultsAt present, the common animal models of hepatocellular carcinoma mainly included spontaneous animal model, induced animal model, gene modified animal model, transplanted animal model, and humanized animal model. The etiology, pathogenesis, and pathophysiological changes of various animal models were different. The selection of animal models of hepatocellular carcinoma depended on the type and purpose of research. ConclusionsVarious animal models of hepatocellular carcinoma have their own advantages and disadvantages. Researchers should choose different animal models according to their own research purposes to achieve the expected experimental purposes, so that more valuable research results of animal models of hepatocellular carcinoma can be applied to clinical practice, and finally these research results can be truly applied to diagnosis and treatment of hepatocellular carcinoma.
ObjectiveTo discuss the feasibility of establishment of animal model of "functional" bicuspid aortic valve with swine and observe its effect on the wall shear stress inside the aorta. MethodsFour common Shanghai White Swine with body weight between 50 kg to 55 kg were selected. Under general anesthesia and cardiopulmonary bypass, the aortic transverse incision approach was used, continuous suture with 6-0 polypropylene to align the left and right coronary valve leaflets to create a bicuspid valve morphology. After the operation, echocardiography was used to observe the aortic valve morphology and the hemodynamic changes of the aortic valve orifice. The effect on the wall shear stress inside the aorta was studied with 4D-Flow magnetic resonance imaging (MRI). ResultsA total of 4 swine "functional" bicuspid aortic valve models were established, with a success rate of 100.0%. Echocardiography showed that the blood flow velocity of the aortic valve orifice was faster than that before the operation (0.96 m/s vs. 1.80 m/s). 4D-Flow MRI showed abnormally increased wall shear stress and blood flow velocity in the aorta of the animal models. After the surgery, in model animals, the maximal wall shear stress inside the ascending aorta was greater than 1.36 Pa, and the maximum blood flow velocity was greater than 1.4 m/s. ConclusionEstablishment of the animal model of "functional" bicuspid aortic valve in swine is feasible, scientific and reliable. It can be used in researches on evaluating the pathophysiological changes.
Objective To summarize the research progress of rodent models of secondary lymphedema (SL) and provide a reference for selecting appropriate animal models in SL research. Methods Recent literature on rodent SL models at home and abroad was comprehensively analyzed, summarizing model categories, development techniques, strengths, and weaknesses. Results Current research primarily utilizes rats and mice to establish SL models. The main model types include hind limb, forelimb, tail, and head/neck models. The hind limb model is the most frequently employed, typically requiring surgery combined with irradiation to induce stable chronic edema. Forelimb models primarily simulate upper limb lymphedema, but exhibit relatively rapid edema resolution. Tail models offer operational simplicity and are predominantly used for studying acute edema mechanisms and interventions; however, they demonstrate poor clinical relevance. Emerging head/neck models provide a valuable tool for investigating head and neck cancer-associated lymphedema. These models exhibit variations in lymphedema duration, degree of fibrosis, and edema incidences. Conclusion Existing models still fall short in faithfully replicating the chronicity, fibrosis, fat deposition, and complex microenvironment characteristic of human chronic lymphedema. Future research must integrate multidisciplinary approaches, optimize model construction strategies, and explore novel modeling approaches to more accurately mimic the human disease and advance SL prevention and treatment research.
ObjectiveTo explore the construction of heart preservation model of empty beating donor based on extracorporeal membrane oxygenation (ECMO). MethodsFrom January 2022 to August 2023, 20 Guangxi Bama miniature pigs weighing 25-30 kg were selected, half male and half female. Under general anesthesia and heparinization, a midline thoracotomy was performed. The pericardium was cut after freeing the anterior and posterior vena cavae, and a perfusion needle was inserted near the brachiocephalic artery in the ascending aorta, connected to a blood collection bag to collect 500-600 mL of blood. The anterior and posterior vena cavae were ligated, the aorta was blocked and perfused with HTK solution to stop the heart beating. The superior and inferior vena cavae were cut off, the right pulmonary vein was decompressed, the aorta and left and right pulmonary arteries and veins were cut off, and the whole heart was removed. An ECMO device was used to continuously perfuse a cardioprotective solution mainly composed of oxygenated warm blood, maintaining the isolated pig heart beating for 8 hours, monitoring (once/hour) ECMO perfusion parameters, blood gas indicators, perfusate electrolytes, detecting inflammatory factors, myocardial enzymes, myoglobin, and troponin levels. Myocardial tissue was taken for hematoxylin-eosin (HE) staining to observe myocardial cell damage and evaluate the quality of heart preservation. ResultsAmong the 20 isolated beating preservation pig hearts, 17 successfully resumed beating, 3 experienced ventricular fibrillation, resuscitated after intracardiac electrical defibrillation, and all 20 pig hearts successfully beat for 8 hours. There was no statistical difference in ECMO perfusion parameters, blood gas indicators, perfusate electrolytes, and inflammatory factors at each time point (P>0.05). There were statistical increases in myocardial enzymes, myoglobin, and troponin levels (P<0.05). HE staining results suggested that there was no severe myocardial damage. ConclusionECMO technology can be used for pig heart preservation with good results, and this study provides experimental evidence for improving heart preservation research in clinical heart transplantation.
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 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.
Objective To explore the feasibility of establishing a rabbit model of flail chest. Methods Flail chest model was eatablished in 12 New Zealand white rabbits after anesthesia and sterile surgery. The paradoxical movement of chest wall was recorded by the biological signal acquisition system, arterial blood was collected for blood gas analysis, the vital signs were recorded by electrocardiogram (ECG) and the lung tissue was taken for the pathological analysis at the end of the experiment. The effect of flail chest on the respiratory function of experimental animals was analyzed to evaluate the feasibility of establishing flail chest model. Results All surgeries were successful without mortality. The operation time was 41.42±7.08 min. Duration of endotracheal intubation was 79.33±12.21 min. Statistical results showed that the pH, partial pressure of arterial carbon dioxide (PaCO2) and base excess (BE) increased; while partial pressure of oxygen (PaO2) and oxygen saturation (SaO2) reduced. Pathological results showed that flail chest not intervented for a long period would lead to organic lesions. Conclusion The rabbit model of flail chest is feasible, safe, repeatable, easy and simple to handle. The animal is easy to access which is the foundation to study the disease process, recovery procedure and the efficacy after intervention.
Objective To study value of severe acute pancreatitis (SAP) rat model induced by retrograde pancreaticobiliary duct infusion of methylene blue in combination with sodium taurocholate. Methods The SPF 90 SD rats, 45 male rats and 45 female rats of them, were randomly divided into control group (C group), sodium taurocholate group (ST group) and methylene blue in combination with sodium taurocholate group (MBST group), which were retrogradely infused with the 0.9% normal saline, sodium taurocholate plus DAPI, and methylene blue plus sodium taurocholate plus DAPI respectively into the pancreaticobiliary duct. The success rate of puncture, degree necrosis of pancreas tissue, range of pancreatic lesions, and the incidence of bile or intestinal leakage were compared among the three groups. Results ① The success rate of puncture in the MBST group was significantly higher than that in the ST group (P=0.003) and the C group (P=0.006), which had no significant difference between the ST group and the C group (P=0.782). ② The necrosis degree of pancreas tissues in the MBST group and ST group became more and more severe with the extension of time (P<0.050), which in the MBST group was more serious than that in the ST group (P<0.050). ③ The point of pancreatic lesions range in the MBST group was significantly higher than that in the ST group (P=0.003). ④ The incidence of bile or intestinal leakage in the MBST group was significantly lower than that in the C group (P=0.008) and the ST group (P=0.004). Conclusions Retrograde pancreaticobiliary duct infusion of methylene blue in combination with sodium taurocholate can improve success rate of puncture, aggravate necrosis degree of pancreatic tissue, increase lesion scope of pancreatic tissue, and reduce rate of bile or intestinal leakage, which can provide a stable animal model for basic research of SAP.