Objective To observe the growth of orthotopic transplanted tumor in nude mice after stomatin-like protein 2 (SLP-2) expression decreased, and to further study the role of SLP-2 in the development and progression of esophageal squamous cell carcinoma. Methods Using RNA interference technique, esophageal squamous cell carcinoma cell lines with specific expression of SLP-2 and stable expression of luciferase were established. The healthy female nude mice with weight ranging from 19 to 22 g were randomly divided into 3 groups (n=12), 6 mice were used to establish subcutaneous xenografts, and the other 6 mice were used to establish the orthotopic transplanted tumor model (Group 1: cell infected with SLP-2-1 plasmid; group 2: cell infected with SLP-2-2 plasmid; group 3: cell infected with SHGFP plasmid). Index of the experiment end was weight loss and poor general situation in any mouse. Before the nude mice were sacrificed, the luciferase value of the tumor was detected by using in vivo imaging technique. After the nude mice were sacrificed, the primary tumor was removed for pathology examination. Results There was no significant difference in region of interest (ROI) value between the group 1 and group 2 (P=0.943). The ROI value for both groups 1 and 2 was significantly lower than that in the group 3 (P=0.002, P=0.000). The primary tumor infiltrated into the muscularis propria of esophageal was observed in all groups. Conclusion SLP-2 is involved in the development and progression of esophageal squamous cell carcinoma, and the decrease of SLP-2 expression can inhibit the growth of esophageal squamous cell 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.
Objective To summarize the research progress on rodent models of cervical spinal cord injury (SCI). Methods The relevant domestic and foreign literature in recent years was reviewed, the methods of establishing the rodent models of cervical SCI and the evaluation methods of behavior, imaging, neuroelectrophysiology, and histology were summarized. Results Cervical SCI involves primary and secondary injuries. Primary cervical SCI can be simulated with contusion, contusion compression, fracture dislocation, spinal cord traction, and spinal cord transection; scondary cervical SCI can be simulated with photochemical model and excitotoxicity model. Certain evaluation methods such as behavior, imaging, neuroelectrophysiology, and histology are used to evaluation during model building and research. Conclusion Different rodent models of cervical SCI have different advantages and application directions, and it is critical importance for the study of cervical SCI to establish effective animal models.
Objective To investigate how to establish stable mice cervical heart transplantation model. Methods Totally, 40 male C57 mice with the age of 6-8 weeks and weight of 19-24 g were randomly divided into recipients and donors (n=20 in each group). Mice cervical heart transplantation model was established by connecting the ascending aorta of donors to the right cervical common artery of recipients through end to side anastmosis and the pulmonary artery of donors to the right external jugular vein of recipients through end to end anastmosis. Results More than 95% recipients survived after surgery. Cold ischemia time was 15±5 min, warm ischemia time 23±6 min, and the whole operation took about 55±15 min. The recipients survived more than 30 d with functional heart grafts. Histologically, there was no difference between the heart graft one month after the transplantion and the normal heart. Conclusion Cervical heart transplantation of mice model is reliable and feasible, which is easy to monitor the survival condition of heart graft by visual examination and palpation, which will benefit the basic research in transplantation field.
Objective To investigate the effect of chaiqin chengqi decoction (CQCQD) on serum lipid metabolism in experimental acute pancreatitis. Methods A total of 27 C57BL/6 mice were randomly divided into three groups (n=9 for each group). The mice in the acute pancreatitis model group (AP group) and the acute pancreatitis model + CQCQD treatment group (APQ group) received seven intraperitoneal injections of cerulein (50 µg/kg) at hourly intervals, while the mice in the control group (CON group) received phosphate-buffered saline injections at the same regimen of cerulein. Oral gavage of CQCQD (5.5 g/kg) or same volume of distilled water was commenced 1 h after the first cerulein injection for three times at intervals of 4 h for the APQ group and AP group, respectively. Animals were sacrificed 12 h after the first cerulein / phosphate-buffered saline injection for collecting serum and tissue samples. The levels of serum lipase and amylase, pancreatic histopathology assessment, as well as pancreatic myeloperoxidase activity, were used to assess the severity of acute pancreatitis and the efficacy of CQCQD. Additionally, serum lipid metabolites were analyzed in all groups. Results In comparison to the CON group, the mice in the AP group exhibited significant edema, inflammatory cell infiltration, necrosis of pancreatic tissues, as well as elevated levels of serum amylase, lipase, and pancreatic myeloperoxidase activity (P<0.05); in comparison to the AP group, inflammatory cell infiltration and necrosis of pancreatic tissue, as well as elevated level of serum amylase significantly reduced in the APQ group (P<0.05). A total of 319 lipid molecules were identified in serum, and 13 lipid metabolites were significantly increased in the AP group and successfully decreased in the APQ group, of which 9 were lyso-phosphatidylethanolamine (LPE) molecules involved in the glycerol phospholipid metabolic pathway. Further statistical analysis revealed that six of these LPE molecules could serve as potential biomarkers. Conclusions CQCQD ameliorated pancreatic injury and serum lipid metabolism disorder of acute pancreatitis model induced by cerulein and significantly improved the abnormal increase of serum LPE level. However, the role of LPE in acute pancreatitis and the underlying mechanisms of CQCQD on LPE metabolic pathways still need further study.
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.
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 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.
Objective To study the mid-facial development characteristics of the goats with cleft palate after in-utero surgical repair at different stages. Methods Twenty-four Boer hybrid female goats were selected, aged from 8 to 12 months and weighing from 35 to 55 kg. The mating day was designated for 0 day. At 30 days, pregnant was confirmed by B-ultrasound test, and the goats were divided into 5 groups (experimental groups 1, 2, 3, 4, and normal control group). Twenty pregnant goats of 4 experimental groups (n=5) were injected DL-anabasine (15 mg/day) from 31 to 42 days to establish cleft palate model of fetal lamb, 4 pregnant goats of normal control group used as controls without injection. At pregnant 65, 90, and 120 days, cleft palate was repaired in the uterus in experimental groups 1, 2, and 3, while cleft palate was not repaired in experimental group 4. After 1 month of birth, the maxillary bone width (posterior premolar morphological measurement, PPMM) and the maxillary bone length (anterior premolar morphological measurement, APMM) were measured with CT scanning. The dry skull of goats were harvested for gross observation. Results There was no significant difference in PPMM and APMM between experimental group 1 and the normal control group (P gt; 0.05), but there were significant differences between experimental groups 1 and 4 (P lt; 0.05) at 1 month after birth. Significant differences were oberved in PPMM and APMM between experimental group 2 and normal control group, experimental group 4 (P lt; 0.05). There were significant differences in PPMM between experimental group 3 and normal control group, experimental group 4 (P lt; 0.05), in APMM between experimental group 3 and normal control group (P lt; 0.05). Five goats with cleft palate in experimental group 4 died at 1-2 months after birth. Conclusion At pregnant 65 days, in-utero surgical repair of cleft palate has less influences on mid-facial development. The earlier repair is performed, the higher risk of miscarriage was.