Objective To investigate the effects of ectomesenchymalstem cells on hematopoiesis after total body irradiation in rats. Methods The primary ectomesenchymal stem cells were isolated from E11.5 SD fetal mandibular processes by 25g/L trypsin and cultured with DMEM/F12. The morphology and growthrate were observed by inverted microscope. Eighty SD male rats randomly dividedinto ectomesenchymal stem cells group (n=20), fibroblast group(n=20), saline group(n=20) and control group(n=20), the first three groups were irradiated with 60Co γ rays at 6.0 Gy. The number of their bone marrow nucleated cells was counted after 4 weeks; the forming ability of colony-forming unit-granulocyte macrophage(CFU-GM) and histopathology of bone marrow were also observed. Results The cultured cells displayed monolayer growth and fibroblast-like with 2-4 processes. The ectomesenchymal stem cells could increase the number of bone marrow nucleated cells and peripheral blood white cell count, and improve the forming ability of CFU-GM. After 4 weeks of transplantation, the number of the peripheral blood white cells in group A was more than that in groups B and C(Plt;0.05), the contents of Hb in groups A and D was significantly higher than those in groups B and C(Plt;0.0). After 4 weeks, the bone morrow nucleated cells in group A were significant more than those in groups B and C(Plt;001); CFU-GM in groups A and D was higher than that in groups B and C(Plt;0.01). Conclusion Ectomesenchymal stem cells have characteristics of stem cells. It may improve hematopoiesis recovery of irradiated rats.
Objective To summarize the online practice teaching experience in laboratory medicine during the coronavirus disease 2019 (COVID-19) epidemic, and explore a new practice teaching mode of laboratory medicine which can provide a reference for improving the efficiency and quality of laboratory medicine education. Methods From June 8th, 2020 to June 30th, 2020, an online questionnaire survey was conducted in teachers and students who participated in online internship teaching and learning during the COVID-19 epidemic to evaluate the effect of online internship teaching and compare the advantages and disadvantages of online and offline internships. ResultsA total of 65 valid questionnaires were collected from 35 students and 30 teachers. There was no statistically significant difference in the satisfaction scores of intern students between online and offline internships [median (minimum, maximum): 100 (80, 100) vs. 100 (80, 100), P>0.05]. Among the teachers surveyed, 90.0% thought that the pre-teaching preparation for online internship teaching was more complicated and time-consuming, 60.0% thought that the online teaching was more difficult, and 63.3% thought that online internship could not achieve the expected results. Both the teachers and students believed that online and offline internships had their own advantages and disadvantages, and they could learn from each other. Conclusions The present online practice model cannot replace the traditional offline practice. A diversified practice model combining online and offline can help further develop and improve medical laboratory practice teaching.
ObjectiveTo compare the long-term survival of elderly patients with esophageal squamous cell carcinoma (ESCC) treated with surgical versus non-surgical treatment. MethodsA retrospective analysis was conducted on the clinical data of elderly patients aged ≥70 years with ESCC who underwent esophagectomy or radiotherapy/chemotherapy at Sichuan Cancer Hospital from January 2009 to September 2017. Patients were divided into a surgical group (S group) and a non-surgical group (NS group) according to the treatment method. The propensity score matching method was used to match the two groups of patients at a ratio of 1:1, and the survival of the two groups before and after matching was analyzed. ResultsA total of 726 elderly patients with ESCC were included, including 552 males and 174 females, with 651 patients aged 70-79 years and 75 patients aged≥80 years. There were 515 patients in the S group and 211 patients in the NS group. The median follow-up time was 60.8 months, and the median overall survival of the S group was 41.9 months [95%CI (35.2, 48.5)], while that of the NS group was only 24.0 months [95%CI (19.8, 28.3)]. The 1-, 3-, and 5-year overall survival rates of the S group were 84%, 54%, and 40%, respectively, while those of the NS group were 72%, 40%, and 30%, respectively [HR=0.689, 95%CI (0.559, 0.849), P<0.001]. After matching, 138 patients were included in each group, and there was no statistical difference in the overall survival between the two groups [HR=0.871, 95%CI (0.649, 1.167), P=0.352]. ConclusionCompared with conservative treatment, there is no significant difference in the long-term survival of elderly patients aged≥70 years who undergo esophagectomy for ESCC. Neoadjuvant therapy combined with surgery is still an important choice to potentially improve the survival of elderly patients with ESCC.