Experimental teaching is an important component of the course Medical Immunology,which requires the use of experimental animals and the execution of experimental animals by medical students.By applying the carbon dioxide euthanasia system,it can effectively reduce the pain of experimental animals,ensure their welfare,and meet ethical requirements.It can also improve the efficiency of experimental teaching in Medical Immunology,reduce environmental pollution,and promote medical students to estab-lish scientific values and worldviews that pay attention to experimental animals and respect life,which is conducive to becoming future medical service talents.In the experimental teaching of Medical Immunology,the appropriate application of carbon dioxide euthanasia system combined with effective ideological and political construction of the curriculum can further implement the Party's educational policy of cultivating morality and talents,and lay a good foundation for cultivating medical talents with comprehensive knowledge,high skills and excellent quality.

Objective:To improve the isolation and culture method of seasonal influenza virus in embryonated chicken eggs (ECEs), and evaluate their isolation efficiency.Methods:We randomly selected 80 positive samples of H1N1 (H1N1pdm09) and seasonal H3N2 (H3N2snl) influenza virus nucleic acid, and inoculated them into the amniotic and urinary sac cavities of 10-day-old (traditional method) and 14-day-old (improved method) ECEs respectively to adapt the virus to the ECEs (E1-E2). Both method were used to inoculate 10-day-old urinary sac amplification virus (E2-E3), and the final virus isolation positive rates of the two method were compared; using fluorescence quantitative PCR method to detect viral nucleic acids in the improved amniotic and urinary sac cultures, and evaluate the viral proliferation at different inoculation sites; we analyzed the correlation between virus content and isolation positivity rate in the original specimen based on the CT value of nucleic acid testing and the final virus isolation positivity rate using the improved method.Results:The improved method obtained 42 strains of H1N1pdm09 strain, with a positive rate of 52.5% ( χ2=38.571, P<0.01); obtained 54 strains of H3N2snl strain, with a positive rate of 67.5% ( χ2=40.921, P<0.01). Significant differences were observed in the isolation efficiency of H1N1pdm09 samples when the improved method was applied to different inoculation sites of chicken embryos ( χ2=30.476, P<0.01), and similar differences were noted for H3N2snl samples ( χ2=4.928, P=0.026). There was no significant difference in the isolation rate of different CT value intervals of the original samples ( χH1N1pdm092=10.226, χH3N2snl2=3.764, P>0.05). Conclusions:The improved method of inoculating 14-day old ECEs adapted the virus, and the final number of strains obtained was significantly higher than the traditional method of inoculating 10 day old ECEs, which can significantly improve the positive isolation rate of H1N1pdm09 and H3N2snl influenza virus in ECEs. The amniotic cavity is more sensitive to H1N1pdm09 and H3N2snl influenza viruses, which helps the virus adapt in ECEs. There was no significant difference in the sample isolation rate and total positive rate of virus isolation among different CT value ranges, and further verification is needed.

Experimental teaching is an important component of the course Medical Immunology,which requires the use of experimental animals and the execution of experimental animals by medical students.By applying the carbon dioxide euthanasia system,it can effectively reduce the pain of experimental animals,ensure their welfare,and meet ethical requirements.It can also improve the efficiency of experimental teaching in Medical Immunology,reduce environmental pollution,and promote medical students to estab-lish scientific values and worldviews that pay attention to experimental animals and respect life,which is conducive to becoming future medical service talents.In the experimental teaching of Medical Immunology,the appropriate application of carbon dioxide euthanasia system combined with effective ideological and political construction of the curriculum can further implement the Party's educational policy of cultivating morality and talents,and lay a good foundation for cultivating medical talents with comprehensive knowledge,high skills and excellent quality.

Objective:To improve the isolation and culture method of seasonal influenza virus in embryonated chicken eggs (ECEs), and evaluate their isolation efficiency.Methods:We randomly selected 80 positive samples of H1N1 (H1N1pdm09) and seasonal H3N2 (H3N2snl) influenza virus nucleic acid, and inoculated them into the amniotic and urinary sac cavities of 10-day-old (traditional method) and 14-day-old (improved method) ECEs respectively to adapt the virus to the ECEs (E1-E2). Both method were used to inoculate 10-day-old urinary sac amplification virus (E2-E3), and the final virus isolation positive rates of the two method were compared; using fluorescence quantitative PCR method to detect viral nucleic acids in the improved amniotic and urinary sac cultures, and evaluate the viral proliferation at different inoculation sites; we analyzed the correlation between virus content and isolation positivity rate in the original specimen based on the CT value of nucleic acid testing and the final virus isolation positivity rate using the improved method.Results:The improved method obtained 42 strains of H1N1pdm09 strain, with a positive rate of 52.5% ( χ2=38.571, P<0.01); obtained 54 strains of H3N2snl strain, with a positive rate of 67.5% ( χ2=40.921, P<0.01). Significant differences were observed in the isolation efficiency of H1N1pdm09 samples when the improved method was applied to different inoculation sites of chicken embryos ( χ2=30.476, P<0.01), and similar differences were noted for H3N2snl samples ( χ2=4.928, P=0.026). There was no significant difference in the isolation rate of different CT value intervals of the original samples ( χH1N1pdm092=10.226, χH3N2snl2=3.764, P>0.05). Conclusions:The improved method of inoculating 14-day old ECEs adapted the virus, and the final number of strains obtained was significantly higher than the traditional method of inoculating 10 day old ECEs, which can significantly improve the positive isolation rate of H1N1pdm09 and H3N2snl influenza virus in ECEs. The amniotic cavity is more sensitive to H1N1pdm09 and H3N2snl influenza viruses, which helps the virus adapt in ECEs. There was no significant difference in the sample isolation rate and total positive rate of virus isolation among different CT value ranges, and further verification is needed.

Objective:To prepare the anti-programmed death-ligand 1 (PD-L1) nanoantibody P3C8-C3Fab by ligating with C3Fab and to investigate its role in plasma half-life.Methods:The C3Fab peptide derived from protein G was molecularly fused with the nanobody P3C8 by DNA recombination technology. The nanoantibody P3C8-C3Fab was inducibly expressed and purified in the E. coli BL21 strain, and the binding of it to PD-L1 protein, mouse IgG, and PD-L1-expressing tumor cells was detected by enzyme-linked immunosorbent assay (ELISA). The residual P3C8-C3Fab was detected in mouse serum at different times using double-antibody sandwich ELISA to assess the prolongation of the plasma half-life of PD-L1 nanobodies by C3Fab. Results:The nanoantibody P3C8-C3Fab was successfully constructed, and it could efficiently express itself in soluble form in BL21. The purified NbP3C8-C3Fab protein was obtained with a mass fraction of about 90% at a yield of 7.18 mg/L. The affinity of P3C8-C3Fab for PD-L1 protein and mouse IgG gradually increased with increasing mass concentration and showed a concentration correlation. The binding of P3C8-C3Fab to lung cancer A549 cells showed a concentration correlation. The concentration standard curve of P3C8-C3Fab in mouse serum showed a typical S-shape with a concentration correlation. The plasma half-life of P3C8 was only 0.44 h, while the plasma half-life of P3C8-C3Fab was 21.27-fold higher, up to 9.36 h.Conclusions:The linkage of C3Fab to the nanobodies of P3C8 can significantly prolong the plasma half-life of P3C8, which is valuable for the improvement of in vivo nanobody effects.

Objective:To evaluate the hemostatic effects of our self-designed pelvic band with inflatable balloon in a swine model of hemodynamically unstable pelvic fracture.Methods:"Open-book like" fractures were created with the external iliac blood vessels exposed in 24 12-month-old female Bama miniature pigs which were randomly divided into 4 groups ( n=6). Group C (the control group) was subjected to no treatment other than exposure of the external iliac blood vessels, group D to no treatment following destruction of the external iliac blood vessels, group T1 to fixation with simple pelvic band after destruction of the external iliac blood vessels, and group T2 to fixation with our self-designed pelvic band with inflatable balloon after destruction of the external iliac blood vessels. The 4 groups were compared in terms of 40-min survival rate, bladder pressure, peak lactate value, total blood loss, bleeding rate, infusion rate, and angiographic images. Results:There was no significant difference in the baseline indexes among the 4 groups before experiment, showing comparability ( P>0.05). The 40-min survival rate in group T2 was 83.3% (5/6), significantly higher than that in groups D and T1 [0% (0/6) and 0% (0/6)] ( P<0.05). There were no significant differences among groups C, D, T1 and T2 in bladder pressure [(6.67±1.03) mmHg, (5.83±1.94) mmHg, (6.00±1.55) mmHg, and (6.00±1.10) mmHg] or in total blood loss among groups D, T1 and T2[(1,198.0±182.9) mL, (1,252.0±148.4) mL, and (1,150.0±125.7) mL] (all P>0.05). The peak lactate value in group T2 [(2.26±0.24) mmol/L] was significantly lower than that in group D [(5.00±0.60) mmol/L] and group T1 [(3.86±0.57) mmol/L], and the bleeding rate and infusion rate in group T2 [(25.83±5.49) mL/min and (26.00±4.69) mL/min] were also significantly lower than those in group D [(83.50±19.85) mL/min and (71.50±29.11) mL/min] and group T1 [(54.17±15.59) mL/min and (54.17±8.98) mL/min] (all P<0.05). Angiography showed contrast agent extravasation in group T2, especially from the artery, but the extravasation speed in group T2 was significantly slower than that in group D. Conclusion:In a swine model of hemodynamically unstable pelvic fracture, our self-designed pelvic band with inflatable balloon has a definite hemostatic effect on vascular injury which is better than that of a simple pelvic band.

Objective: To investigate the prognostic factors of children with congenital heart disease (CHD) who had undergone cardiopulmonary resuscitation (CPR) in pediatric intensive care unit (PICU) in China. Methods: From November 2017 to October 2018, this retrospective multi-center study was conducted in 11 hospitals in China. It contained data from 281 cases who had undergone CPR and all of the subjects were divided into CHD group and non-CHD group. The general condition, duration of CPR, epinephrine doses during resuscitation, recovery of spontaneous circulation (ROSC), discharge survival rate and pediatric cerebral performance category in viable children at discharge were compared. According to whether malignant arrhythmia is the direct cause of cardiopulmonary arrest or not, children in CHD and non-CHD groups were divided into 2 subgroups: arrhythmia and non-arrhythmia, and the ROSC and survival rate to discharge were compared. Data in both groups were analyzed by t-test, chi-square analysis or ANOVA, and logistic regression were used to analyze the prognostic factors for ROSC and survival to discharge after cardiac arrest (CA). Results: The incidence of CA in PICU was 3.2% (372/11 588), and the implementation rate of CPR was 75.5% (281/372). There were 144 males and 137 females with median age of 32.8 (5.6, 42.7) months in all 281 CPA cases who received CPR. CHD group had 56 cases while non-CHD had 225 cases, with the percentage of 19.9% (56/281) and 80.1% (225/281) respectively. The proportion of female in CHD group was 60.7% (34/56) which was higher than that in non-CHD group (45.8%, 103/225) (χ²=4.00, P=0.045). There were no differences in ROSC and rate of survival to discharge between the two groups (P>0.05). The ROSC rate of children with arthythmid in CHD group was 70.0% (28/40), higher than 6/16 for non-arrhythmic children (χ²=5.06, P=0.024). At discharge, the pediatric cerebral performance category scores (1-3 scores) of CHD and non-CHD child were 50.9% (26/51) and 44.9% (92/205) respectively. Logistic regression analysis indicated that the independent prognostic factors of ROSC and survival to discharge in children with CHD were CPR duration (odds ratio (OR)=0.95, 0.97; 95%CI: 0.92~0.97, 0.95~0.99; both P<0.05) and epinephrine dosage (OR=0.87 and 0.79, 95%CI: 0.76-1.00 and 0.69-0.89, respectively; both P<0.05). Conclusions: There is no difference between CHD and non-CHD children in ROSC and survival rate of survival to discharge was low. The epinephrine dosage and the duration of CPR are related to the ROSC and survival to discharge of children with CHD.
Cardiopulmonary Resuscitation ; Child ; Child, Preschool ; Female ; Heart Arrest/therapy* ; Heart Defects, Congenital/therapy* ; Humans ; Intensive Care Units, Pediatric ; Male ; Retrospective Studies

Hand, foot and mouth disease (HFMD) is an acute infectious disease induced by enterovirus. More than 30 pathogenic viruses for hand, foot and mouth disease have been discovered, of which enterovirus 71 (EV-A71) and Coxsackievirus A16 (CV-A16) are the most common. Enterovirus 71 (EV-A71) is also the main cause of severe hand, foot and mouth disease. In recent years, it has been discovered that Coxsackievirus A6 (CV-A6) infection has broken out in many regions of the world, and the pathogenicity rate is increasing, which indicatesthat it may rise to become a new major pathogenic agent of hand, foot and mouth disease. Hand, foot and mouth disease has become a global public health problem. Therefore, research on the pathogenic mechanism of multiple enteroviruses that induce hand, foot and mouth disease and analysis of its epidemiology will become the top priority of prevention, control and treatment of the disease.

We reported a case of irreducible indirect inguinal hernia caused by sigmoid colon cancer entering the right groin.The patient complained about a right groin mass for more than 60 years with progressive enlargement for 3 years and pain for half a month.Abdominal CT examination at admission showed rectum and sigmoid colon hernia in the right inguinal area and thickening of sigmoid colon wall.Electronic colonoscopy and pathological diagnosis showed sigmoid colon cancer.Therefore,the result of preliminary diagnosis was irreducible indirect inguinal hernia caused by sigmoid colon cancer entering the right groin.We converted laparoscopic exploration to laparotomy followed by radical sigmoidectomy and employed end-to-end anastomosis of descending colon and rectum in combination with repair of right inguinal hernia.The patient recovered well after operation and was discharged.
Colon, Sigmoid/surgery* ; Groin ; Hernia, Inguinal/surgery* ; Humans ; Laparoscopy ; Sigmoid Neoplasms/surgery*