The enterotoxigenic Escherichia coli (ETEC) infection is a major factor restricting the development of animal husbandry. However, the abuse of antibiotics will lead to the antibiotic residues and emergence of antibiotic-resistant bacteria. The existing vaccines face challenges in stimulating intestinal immunity, demonstrating limited prevention effects. Therefore, it is indispensable to develop a new vaccine that is safe and suitable as a feed additive to activate intestinal immunity. This study constructed yeast-cell microcapsules (YCM) carrying the DNA vaccine against ETEC by genetic engineering. Furthermore, animal experiments were carried out to explore the regulatory effects of feeding YCM on the intestinal immune system and intestinal microbiota. Saccharomyces cerevisiae was selected as the oral delivery vehicle (microcapsules) of the DNA vaccine. The codon-optimized nucleic acid sequence of K88, the main antigen of mammal-derived ETEC, was synthesized, and the yeast shuttle vector containing the corresponding DNA vaccine expression cassette was constructed by DNA recombination. The recombinant strain of YCM was prepared by transforming JMY1. Additionally, the characteristics of the YCM strain and its feasibility as an oral vaccine were comprehensively evaluated by the fluorescence reporter assay, gastrointestinal fluid tolerance assay, intestinal epithelial cell adhesion assay, intestinal retention assessment, antiserum detection, and intestinal microbiota detection. The experimental results showed that the DNA vaccine expression cassette was expressed in mammals, and the recombinant strain of YCM could tolerate up to 8 hours of gastrointestinal fluid digestion and had good adhesion to intestinal epithelial cells. The results of mouse feeding experiments indicated that the recombinant strain of YCM could stay in the intestinal tract for at least two weeks, and the DNA vaccine expression cassette carried by YCM entered the intestinal immune system and triggered an immune response to induce the production of specific antibodies. Moreover, feeding YCM recombinant bacteria also improved the abundance of gut microbiota in mice, demonstrating a positive effect in regulating intestinal flora. In summary, we prepared the recombinant strain of YCM carrying the DNA vaccine against ETEC and comprehensively evaluated its characteristics and feasibility as an oral vaccine. Feeding the recombinant YCM could induce specific immune responses and regulate intestinal microbiota. The findings provide a reference for the immunoprevention of ETEC-related animal diseases.
Animals ; Enterotoxigenic Escherichia coli/genetics* ; Saccharomyces cerevisiae/metabolism* ; Vaccines, DNA/genetics* ; Mice ; Escherichia coli Infections/immunology* ; Escherichia coli Vaccines/genetics* ; Capsules ; Mice, Inbred BALB C ; Female

Objective:To explore the effect of SimMan 3G simulator based scenario simulation teaching method and case-based learning (CBL) in emergency medicine teaching.Methods:Sixty students from Batch 2013 eight-year program of clinical medicine were selected as subjects. They were randomly divided into an experimental group and a control group, with 30 students in each group. In the teaching of emergency medicine, the experimental group used the combination of scenario simulation with CBL teaching methods, and the control group used classic teaching methods. The test scores and the questionnaires satisfaction of the two groups were compared to evaluate the teaching effects. SPSS 17.0 was used for the statistical analysis, measurement data were compared between the groups by t test, and counting data were compared between groups by chi-square test.Results:The scores of the experimental group (94.24±1.13) were better than those of the control group (90.6±0.59), with significant differences ( t=12.85, P<0.05). The results of the questionnaires showed that the students of experimental group were more satisfied with the learning experience than those of the control group. Conclusion:The teaching method can improve the teaching effects, the students' emergency clinical thinking, skills, comprehensive analysis and judgment ability, team cooperation consciousness and leadership ability.

Fetal cystic lymphangioma is a developmental anomaly of the lymphatic system, which can occur in any part of the body, but most commonly in the neck and armpit. A case of fetal cystic lymphangioma located at the chest wall under the right armpit with a size of 21 mm×18 mm×16 mm is reported here. The mass was initially diagnosed by routine ultrasound examination at 21 gestational weeks. After the diagnosis, ultrasound was repeated every 4 weeks till 37 +4 gestational weeks. Over this period, the mass increased progressively to 101 mm×110 mm×95 mm. Ultrasound-guided intrauterine fetal cystic mass puncture and aspiration was performed 38 +4 weekss, and Bleomycin was injected into the cyst after operation and on day 42 after birth. During a follow-up to 10 months after birth, no obvious cystic mass was found at the right axillary chest wall of the child.

Objective To investigate the relationship between QRS wave terminal distortion with coronary arterial lesion and serum high-sensitivity cardiac troponin I (hs-cTnI) in early stage of acute ST-segment elevation myocardial infarction (STEMI).Methods One hundred and twenty patients with STEMI were classified into the QRS wave distortion positive group(QRS+,n=81) and non-QRS wave distortion group(QRS-group,n=39) according to EKG on admission.The two groups all conducted the coronary angiography and hs-cTnI detection.The coronary arterial lesion occurrence situation and hs-cTnI level were compared between the two groups.Results (1) In the QRS+ group:68 cases (83.59％) were male and 13 cases (16.05％) were females;in the QRS-group:27 cases(69.23％) were male and 12 cases (30.77％) were female.The sex difference had statistical significance (P＜0.05).(2) The occurrence rate of left anterior descending artery (LAD) lesion in the QRS+ group was higher than that in the QRS-group,the difference was statistically significant (P＜0.05).But the occurrence rate of left circumflex coronary artery (LCX) lesion in the QRS-group was higher than that in the QRS+ group,the difference was statistically significant (P＜0.01).(3) The hs-cTnI level in the QRS+ group was higher than that in the QRS-group,the difference was statistically significant (P ＜0.01).Conclusion The patients with QRS wave distortion positive have a higher occurrence rate of LAD lesion,while the patients with out QRS wave distortion negative have higher occurrence rate of LCX lesion;the QRS wave terminal distortion has relationship with serum hs-cTnI level.