The role of IL-22 in T cell reconstitution after thymus damage induced by ionizing radiation / 中华血液学杂志

Objective: To explore the levels of IL-22 in thymus damaged by γ-ray total body irradiation (TBI), and to study the role of IL-22 in T cell reconstitution after thymic injury induced by TBI. Methods: To induce thymic injury, mice were treated by sub-lethal TBI. Levels of intra-thymic and circulatory IL-22 were detected by using ELISA assay. Untreated mice were used as control. After receiving sub-lethal TBI, mice were intraperitoneally injected with PBS or recombinant mouse IL-22, which were marked as TBI+PBS or TBI+IL-22, respectively. Mice were monitored for counts of total thymic cells and circulatory white blood cells. Flow cytometry was applied to analyze percentages of thymic epithelial cells (TEC), thymocyte subsets and circulatory T cells. Real-time PCR assay was applied to analyze the mRNA expression levels of Foxn1, Ccl25, Aire and Dll4 in thymus. Results: ①Sub-lethal TBI treated mice expressed higher levels of intra-thymic and circulatory IL-22, compared with untreated ones (all P<0.05). ②After injection of recombinant IL-22, TBI+IL-22 mice had higher levels of intra-thymic IL-22 than TBI+PBS mice (all P<0.05). ③On day 14 after irradiation, real-time PCR assay showed that TBI+IL-22 mice had higher mRNA levels of Foxn1, Ccl25, Aire and Dll4 in thymus compared with TBI+PBS ones. Meanwhile, the TBI+IL-22 mice had higher counts of total thymic cells[(5.93±3.19)×10(6)/ml vs (1.42±0.46)×10(6)/ml, t=3.128, P=0.033] and circulatory white blood cells[(3.08±0.94)×10(6)/ml vs (1.43±0.30)×10(6)/ml, t=3.730, P=0.015] than those of TBI+PBS mice. Flow cytometry analysis indicated that TBI+IL-22 mice had higher counts of TEC and thymocytes than TBI+PBS mice on day 14 after irradiation (all P<0.05). On days 7 and 14 after irradiation, TBI+IL-22 mice had higher counts of circulatory white blood cells and T cells than TBI+PBS mice (all P<0.05). Conclusion: Sub-lethal TBI induces upregulation of intra-thymic IL-22, and injecting of recombinant IL-22 increases level of IL-22 in thymus. Injecting of recombinant IL-22 improves recovery of TEC and increases numbers of thymocyte subsets and circulatory T cell after thymic injury.

Discussion on Education for Information Literacy of Medical Student through Medical College Library / 医学信息学杂志

The paper analyzes the current situation and deficiency of education for information literacy of medical students through medical college library,elaborates measures to improve information literacy education of medical students from aspects like enrichment of connotation of library entry education for freshmen,promotion of literature retrieval course reform and improvement of information literacy of librarians in medical college library.

Dual effects of extract of Schisandra chinensis Baill on rat hepatic CYP3A / 药学学报

This study is to investigate the effects of aqueous extract of Schisandra chinensis Baill (WWZ), kadsurin, schisandrin A, schisandrin B and schisandrol B on rat hepatic CYP3A. Rats received a daily gavage of aqueous extract of WWZ for different times. The livers were harvested after gavage and subjected to microsome preparation. Microsomal CYP3A activity was determined by measuring the amount of the metabolite of testosterone (6 beta-hydroxytestosterone) with HPLC. Aqueous extract of WWZ, kadsurin and schisandrin A were incubated with microsomes obtained from rat. Microsomal CYP3A activity was determined by HPLC. Primary hepatocytes were separated and extracted from rat, then were treated with aqueous extract of WWZ, schisandrin A, schisandrin B and schisandrol B. Then, the expression of CYP3A1 mRNA was analyzed by RT-PCR. As for the in vivo assay, aqueous extract of WWZ significantly inhibited the enzyme activity of CYP3A after 12 h gavage. The inhibitory effect was converted to inductive effect after 3-day gavage. Aqueous extract of WWZ could induce the enzyme activity of CYP3A after 6-day gavage. Aqueous extract of WWZ and kadsurin showed a dose-dependent inhibition of CYP3A (IC50 of 487.8 microg mL(-1) and 6.2 micromol L(-1), separately). In rat primary hepatocytes, aqueous extract of WWZ (2.5 mg mL(-1)), schisandrin A (0.1 micromol L(-1)), schisandrin B (0.1 micromol L(-1)) and schisandrol B (10 micromol L(-1)) increased significantly the expression of CYP3A1 mRNA by 23%, 55%, 42% and 27%, respectively. Aqueous extract of WWZ could show dual effect on the enzyme activity of CYP3A in rat in vivo. Meanwhile, kadsurin showed a dose-dependent inhibition of the enzyme activity of hepatic CYP3A in vitro. And schisandrin A, schisandrin B and schisandrol B showed significant inductive effect on the expression of rat CYP3A1 mRNA.