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The virtual prototyping technology and the finite element analysis method were used to simulate the motion mechanism of a type of air conditioner panel in order to reduce the possibility of the mechanism failure at the design stage. First,the motion of air conditioner panel is analyzed by ADAMS software and load is exported. The results show that the overall motion of the panel is stable,but a large speed change occurs when the panel is fully open. The maximum load appears in the process of air conditioning start-up. Second,the software ABAQUS was used to analyze the stress. It is indicated that the maximum stress region is the contact position between the gear and the rack when the air conditioning starts up. The maximum stress area is the contact position for rack and pinion when the panel is fully open. In both cases,the maximum stress values satisfy the strength requirements. Finally,the simulation analysis is verified by experimental results of Lab VIEW platform.

Objective: To investigate the effect of up-regulation of Rap1GAP on the invasion ability of leukemic HL-60 cells in vitro, and to establish leukemia mouse model to verify the effects in vivo., Methods: Quantitative RT-PCR and Western blot methods were used to detect the expression of Rap1GAP in Venus/HL-60 (vehicle control) and Rap1GAP/HL-60 cells (R1 andR2). Transwell method was used to examine the invasion ability in vitro. Quantitative RT-PCR and gelatin zymograph were used to study the expression of MMP-2 and MMP-9. Four-week-old BALB/c nu/nu mice were pre-treated and inoculated with leukemic cells from different groups, several index including survival time were then monitored., Results: Rap1GAP mRNA level of R1 and R2 increased about 16-17 folds as compared to the control cells. The invasion rate of R1 and R2 are (55 ± 5)% and (59 ± 4)%, which are significantly higher than (14 ± 4)% of the control cells. The mRNA level of MMP-9 was up-regulated about 12.0 folds in R1 and R2 cells compared to the corresponding control cells. The median survival times of R1 and R2 mice are (32.00 ± 1.85) d and (33.37 ± 2.50) d, respectively, which are shorter than (43.62 ± 2.32) d of the control group. Three mice of R1 and R2 groups showed leukemic cells infiltration in meninges tissue, and the genes of Rap1GAP and MMP-9 were amplified by PCR method., Conclusion: Up-regulated expression of Rap1GAP increased the invasion ability of HL-60 cells accompanied with enhancement of MMP-9 expression in vitro, and the experiment in mouse model also confirmed that Rap1GAP enhanced the invasion of HL-60 cells in vivo.

Objective: To investigate the sensitivity of imatinib (IM) on Sup-B15 Ph+ acute lmphoblastic leukemia (ALL) cells indused by stromal cells OP9, and to further explore its mechanism., Methods: The study is divided into two group, Sup-B15 cells group and co-cultured with OP9 cells group (Sup-B15/OP9 group). The inhibitory effects of IM on leukemia cells were measured by CCK-8 test, and the apoptosis by Annexin Ⅴ/7-AAD dyeing and the percentage of CD 34+CD38- leukemia cells were determined by flow cytometry. ALDH1, CD144, and β-catenin mRNA were detected by real-time RT-PCR, protein levels by Western blot. Inmunoprecipitation was used to detect the level of β-catenin connected to CD144., Results: IM presented inhibitory effects on Sup-B15 and Sup-B15/OP9 cells at multiple concentrations from 10 μmol/L to 45 μmol/L. The IC50 of IM on Sup-B15/OP and Sup-B15 cells were 35.8 μmol/L and 6.3 μmol/L, respectively (P<0.05). After 24 h of 30 μmol/L IM treatment, the percentages of apoptosis cells in Sup-B15/OP9 and Sup-B 15 cell were (14.24 ± 2.11)% and (3.45 ± 0.68)%, respectively (P<0.05). The percentage of CD34+CD38- cells in Sup-B15/OP9 group was significantly higher than that in Sup-B15 group [(3.42 ± 0.28)% vs (0.16 ± 0.15)%, P<0.05]. As compared to Sup-B15 cells, the transcription of ALDH1 in Sup-B15/OP9 group was remarkably upregulated (0.097 ± 0.012 vs 0.046 ± 0.010, P<0.05), and the CD133 protein level was also upregulated in Sup-B15/OP9 group. The transcription of CD144 in Sup-B15/OP9 group was remarkably upregulated compared with Sup-B15 group (0.103 ± 0.015 vs 0.010±0.003, P<0.05), as well as the CD144 protein. β-catenin mRNA transcription has no obvious changes between Sup-B15 group and Sup-B15/OP9 group (P>0.05), while the whole β-catenin protein and the cell nucleus β-catenin significantly increased, as well as the β-catenin protein combined with CD144., Conclusion: Co-cultured with OP9 cells, Sup-B15 cells show less sensitivity to imatinib. The raising activity of CD144 and CD144/β-catenin signaling may work in this procession.

Objective: To observe the efficacy of high-dose dexamethasone in combination with low-dose rituximab as a second-line treatment for patients with immune thrombocytopenia (ITP)., Methods: 65 patients with ITP, previously by conventional dose of glucocorticoids, received high-dose dexamethasone in combination with low-dose rituximab (dexamethasone 40 mg/d for 4 days, rituximab 100 mg, d 7, 14, 21, 28 intravenous infusion). Treatment response, regulatory T cells (Treg), cytokines levels and treatment-related adverse effects were observed., Results: Total response rate 1 month after treatment was achieved in 81.5% (53/65) of patients, and complete response at 3,6 and 12 months was 72.3% (47/65), 66.2%(43/65), 63.1%(41/65). The higher efficiency and complete response rate was achieved in preexisting glucocorticoid-dependent patients. For patients with complete response, Treg cells continued to show a high level state [(3.01 ± 0.95)% vs (1.69 ± 0.35)%, P=0.032], cytokines of BAFF [(648.03 ± 79.63) ng/L vs (972.35 ± 93.64) ng/L, P=0.001], IL-2 [(2.84 ± 0.32) ng/L vs (4.18 ± 0.46) ng/L, P=0.012], sCD40L[(4.55 ± 0.66) ng/L vs (7.73 ± 1.04) ng/L, P=0.006] significantly lower than that before treatment. The level of IL-10 was increased, but without significance compared with that before treatment (P=0.136). All patients completed the protocol with no serious adverse reactions., Conclusion: The data show high-dose dexamethasone in combination with low-dose rituximab still has a satisfactory outcomes for patients previously with conventional dose of glucocorticoid.

Objective: To explore the expression and significance of miRNAs and Th17 related cytokines in patients with multiple myeloma (MM)., Methods: A total of 27 MM patients and 8 health controls were enrolled in this study. The expression of miR-15a/16,miR-34a,miR-194-2-192 cluster and miR-181a/b in bone marrow were detected by real-time quantitative PCR (qRT-PCR). Enzyme-linked immunosorbent assay (ELISA) was used to determine the levels of Th17 related cytokines interleukin-17 (IL-17), IL-21, IL-22, IL-23 and IL-27 in peripheral blood plasma. The role of miRNAs and Th17 related cytokines was analyzed in the development of MM., Results: The expression of miR-15a/16,miR-34a,miR-194-2-192 cluster in MM patients were significantly lower than those of the health controls, while miR-181a/b were exactly the reverse (P<0.05). The levels of IL-17, IL-21 and IL-27 were up-regulated in MM patients compared to health controls while IL-22 was down-regulated (P<0.05). There was no significant difference of IL-23 between the two groups. The levels of miRNAs and Th17 related cytokines had associated with ISS but not with some clinical parameters (such as gender, age, disease classification). Higher expression of IL-17, IL-21, IL-23, IL-27, miR-181a/b and lower expression of miR-15a/16,miR-34a,miR-194 and IL-22 were observed in the end stage than the early stage of MM patients (P<0.05). There was a significant correlation between miRNAs and Th17 related cytokines., Conclusion: Up-regulated IL-17, IL-21 and IL-27 may potentially down-regulate the expression of several miRNAs in MM patients. Establishment of the relationship may be useful for understanding the pathogenesis of MM and for clinical diagnosis of the disease.