BACKGROUND:Leukemia cells can obtain drug resistance phenotype mediated by adhesion to bone marrow stromal cells. But, for chronic myelogenous leukemia with adhesion functional defects, the role and mechanism of bone marrow stromal cells in imatinib-resistant formation remain unclear. OBJECTIVE:To construct the co-cultured model of bone marrow stromal cells-K562 cells and to investigate the influences of the co-culture with bone marrow stromal cells from the patients with chronic myelogenous leukemia on imatinib sensitivity of K562 cells and cellcycle. METHODS:The co-culture model was constructed by co-culturing K562 cells with bone marrow stromal cells isolated and cultured from the patients with chronic myelogenous leukemia. The IC50 values of K562 cells exposed to imatinib were quantified by MTT assay. The apoptotic rates of K562 cells exposed to 0.5μmol/L imatinib for 72 hours were detected by flow cytometry through Annexin V-FIT/PI labeling. The cellcycles, cellcycle protein (cyclin A, cyclin D1 and cyclin E) expression of K562 cells co-cultured with bone marrow stromal cells for 72 hours were analyzed by flow cytometry.RESULTS AND CONCLUSION:The IC50 values of co-culture group and suspension culture group were respectively (0.52±0.02)μmol/L and (1.27±0.05)μmol/L, and their comparison showed significant differences (P<0.01). After 72 hours of treatment with 0.5μmol/L imatinib, the apoptotic rates in the co-culture group and suspension culture group were respectively (15.48±4.17)%and (32.01±6.83)%, and their comparison showed significant differences (P<0.01). The percentages of G0-G1 phase of K562 cells co-cultured with bone marrow stromal cells for 72 hours were (48.81±8.27)%, which were significantly higher than the suspension culture group (25.78±3.26%) (P<0.01). The co-culture with bone marrow stromal cells from the patients with chronic myelogenous leukemia could mediate K562 cells resistance to imatinib. The mechanism was possibly related with G0/G1 arrest of K562 cells induced by co-culture with bone marrow stromal cells.

Objective To study the value of electronic administration analysis system used for pre-hospitalrecords in comparison with statistic data processed manually. Method The data of 'first aid medical records'collected from June 26, 2007 to December 26, 2007 in Wuxi Emergency Center, Wuxi, China were taken for anal-ysis. The items for comparison included the average number of emergency patients monthly, percentage of intra-venous infusion, proportion of ECG and blood oxygen saturation monitoring, rate of blood glucose measurement,number of pre-hospital treatment, frequency of using medical devices and time taken for answer to inquires. Thecomparison was carried out between statistic data processed manually and those processed electronically. ResultsBetween two different methods of statistic process, there were no significant in all items ( P > 0.05) except theshorter time required for electronic process to answer the inquires (P<0.01). Conclusions The electronic ad-ministration analysis system for the records of emergency patients is fully developed to meet the expectation in termsof quick answer to inquries with credibly and precisely numerical values.

Objective To investigate the effects of adhesion mediated by bone nlalTow stroma celh from leukemia patient on chemotherapeutics sensitivity and cell cycle of Jurkat cells in the co-cultured model.Methods Bone mw stroma cells were isohted and cultured from leukemia patients routinely.To construct the co-cultured model.Jurkat cells were co-cultured with BMSCs the irradiated layer by 60Co,and the model was observed with scanning electron microscope.The IC50 values of Jurkat cells expesured to DNR were quantified by MTT.The cell cycles of Jurkat cells after 24h-adhesion in the co-cultured model were analyzed by Facs.The expression of cyclin A,cyclin E and p27 in Jurkat cells adhered to BMSCs for 4h.24h and 48h were detected by Western blot.Results Jurkat ceUs in the co-cultured model showed a decreased sensitivity to DNR.ICSO values for normal BMSCs,leukemic BMSCs and non-adhered control were of 1.78Ixmol/L,2.30pznol/L and 0.45p,mol/L,respectively.The percentages of Go-Gl phase for leukemic BMSCs group and non-adhered control group were of 48.74％±8.77％and 27.83％壬1.86％.Respectively.The percentages of Gz-M phase for leukemic BMSCs group and non-adhered control group were of2.01％±1.17％and 20.33％±1.84％。Respectively.Compared with eomrol group,the 24h-ad- hesion mediated by BMSCs from leukemia patients up-regulated the percentage of Go-G1 phase of Jurkat cells(P

Objective To explore the cognitive load level and influencing factors of emergency nurses.Methods Using convenience sampling method,48 nurses in emergency department of China-Japan Friendship Hospital from April to May 2022 were selected as research objects.General data were collected and total cognitive load and three different types of cognitive load were measured.Results Regression analysis showed that nurse-patient relationship was influencing factor of total cognitive load of nurses in emergency department(β=6.202,P=0.007),the noisy working environment was the influencing factor of the internal cognitive load(β=1.042,P<0.001),and the living situation(sharing with others)was the influencing factor of the external cognitive load(β=-3.917,P=0.006).The factors of associated with cognitive load were not found.Conclusion The total cognitive load and the three types of cognitive load of nurses in emergency department are high.Nursing managers can reduce the cognitive load of nurses in emergency department by adjusting related influencing factors,so as to improve nursing work efficiency.