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 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.
This study aims to evaluate the ability of C-arm cone-beam CT to detect intracranial hematomas in canine models. Twenty one healthy canines were divided into seven groups and each group had three animals. Autologous blood and contrast agent (3 mL) were slowly injected into the left/right frontal lobes of each animal. Canines in the first group, the control group, were only injected with autologous blood without contrast agent. Each animal in all the 7 groups was scanned with C-arm cone-beam CT and multislice computed tomography (MSCT) after 5 minutes. The attenuation values and their standard deviations of the hematoma and uniformed brain tissues were measured to calculate the image noise, signal to noise ratio (SNR) and contrast to noise ratio (CNR). A scale with scores 1-3 was used to rate the quality of the reconstructed image of different hematoma as a subjective evaluation, and all the experimental data were processed with statistical treatment. The results revealed that when the density of hematoma was less than 65 HU, hematomata were not very clear on C-arm CT images, and when the density of hematoma was more than 65 HU, hematomata showed clearly on both C-arm CT and MSCT images and the scores of them were close. The coherence between the two physicians was very reliable. The same results were obtained with C-arm cone-beam CT and MSCT grades in measuring SD value, SNR, and CNR. The reasonable choice of density detection range of intracranial hematoma with C-arm cone-beam CT could be effectively applied to monitoring the intracranial hemorrhage during interventional diagnosis and treatment.
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.
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.
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 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 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.
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.
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.
