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To predict the effect of microorganisms breeding in cutting fluid on the corrosion of 2219 aluminum alloy( AA 2219) used in aerospace, the corrosion rate of microorganisms in cutting fluid on 2219 aluminum alloy was analyzed by weight loss method. The adhesion of microorganisms on the surface of 2219 aluminum alloy was observed by inverted fluorescent microscope. The corrosion morphology of products and the corrosion profile after removing corrosion products were observed by scanning electron microscope( SEM) and white light interferometer, respectively. The elements of surface corrosion products were analyzed by energy dispersive spectroscopy (EDS), and the corrosion mechanism was studied by electrochemical impedance spectroscopy( EIS). The results indicate that the microorganisms in the cutting fluid adhere to the surface of 2219 aluminum alloy to form uneven corrosion product film and biofilm. The presence of microorganisms increase the corrosion rate of 2219 aluminum alloy by 59%. After removing the surface film, obvious pitting pits are found, and the maximum depth is 9.96 µm. The electrochemical results also show that the charge transfer resistance of aluminum alloy immersed in cutting fluid with microorganisms decreases and the corrosion rate increases significantly. The microorganisms in the cutting fluid accelerate the corrosion of 2219 aluminum alloy obviously, and pitting corrosion is the main form of corrosion. [ABSTRACT FROM AUTHOR]

This study briefly introduces the revised content of Guidance for Registration of Metallic Bone Plate Internal Fixation System ( Revised in 2021 ) compared to the original guidance, mainly including the principles of dividing registration unit, main performance indicators of standard specification, physical and mechanical performance research, and clinical evaluation. At the same time, in order to provide some references for the registration of metallic bone plate internal fixation system, this study analyzes the main concerns in the review process of these products based on the accumulation of experience combining with the current review requirements.

Objective: Sepsis is a life-threatening organ dysfunction caused by dysregulated host responses to infection. Despite decades of research, it remains the leading cause of death in intensive care units (ICUs). None of the current treatment, including antibiotics, organ protection and liquid resuscitation, is specifically effective for sepsis. Immunosuppression is one of the currently accepted pathogenesis and immunotherapy is one of the hot spot of current sepsis research. Immune related treatments include restricting the release of pathogen toxin and its removal, controlling the excessive inflammatory reaction and apoptosis inhibition, etc. Numerous pre-clinical studies using immunomodulatory agents such as interleukin-7 (IL-7), anti-programmed cell death-1 (PD-1) antibody and others, have demonstrated reversal of T cell dysfunction and improved survival resulting from reviewing recent advances in immunotherapy of sepsis. Therefore, immunotherapy may be a new way of sepsis treatment.

Objective: To evaluateclinical features, treatment and outcomes of patients diagnosed with primary breast diffuse large B-cell lymphoma（DLBCL）., Methods: Clinical data were analyzed for all patients diagnosed with primary breast DLBCL（n=21）. Kaplan-Meier method was used to estimate 5- year overall survival（OS）rate, and the difference was compared by Log- rank test., Results: The 21 cases of patients with primary breast DLBCL were all female with median age at diagnosis as 48 years （range 21-64 years）. 13 patients had International Prognostic Index（IPI）of 0, 6 IPI 1, and 2 IPI 2. The 5- year OS rates of CHOP/R- CHOP and R±DICE after R±EPOCH groups were 40.0% and 72.2% , respectively（P=0.035）. The central nervous system relapse rate of CHOP/R-CHOP and R±DICE after R± EPOCH groups were 16.7% and 6.7%（P=0.500）, respectively. The 5- year OS rates of patients with primary breast DLBCL staging Ⅱ E-Ⅲ E and Ⅰ E were 21.4% and 83.3% , respectively（P=0.025）., Conclusion: Primary breast DLBCL was rare. The patients of primary breast DLBCL with chemotherapy regimen of R±DICE after R±EPOCH might have a better prognosis and lower relapse rate of central nervous system; the primary breast DLBCL patients staging ⅡE-ⅢE might have a poor prognosis.

Objective: To investigate the effect of ERK1/2 inhibitor AZD8330 on human Burkitt's lymphoma cell line Raji cells and its mechanism., Methods: Raji cells were treated with different concentrations of AZD8330. CCK-8 was used to detect the cell viability. The apoptosis rate of Raji cells was detected by flow cytometry using Annexin V/PI-staining. Real-time PCR was used to assess the expression of Bcl-2, Bcl-xl, caspase-3 and VEGF genes. The protein expression level of Bcl-2, Bcl-xl, caspase-3 and p-ERK1/2 was tested with Western blot., Results: The cell survival rate decreased to(62.09±0.86)%,(50.06±1.33)% and (39.13±2.34)% respectively after cells were treated with AZD8330 at 1.00 μmol/L in vitro for 24 h, 48 h and 72 h, and statistically significant differences were observed in groups with different time of treatment(P<0.05). Apoptosis of cells treated with AZD8330 at 0.10, 1.00, 10.00 μmol/L in vitro for 24 h, 48 h and 72 h was analyzed, and the statistically significant differences were observed in groups of different time and concentration treatment (P<0.05). AZD8330 induced Raji cell apoptosis and upregulated expression of Bcl-2, Bcl-xl, VEFG and decreased the expression of caspase-3 in a dose and time dependent manner, and statistically significant differences were observed in groups of different time and concentration treatment (P<0.05). At the same time, the Bcl-2, Bcl-xl and p-ERK1/2 proteins expression is suppressed obviously, but the expression of caspase-3 protein increased., Conclusion: AZD8330 induces cell apoptosis by down-regulating the activation of ERK1/2 signal transduction pathway in Burkitt's lymphoma cell line Raji cells in a dose and time dependent manner.

Objective: To compare the efficacy and adverse events of adjusted BACOD (bleomycin, doxorubicin, cyclophosphamide, vincristine, dexamethasone) regimen (continuous intravenous infusion) and conventional BACOD regimen (conventional intravenous drip) in the treatment of relapsed and refractory diffuse large B cell lymphoma (DLBCL)., Methods: Retrospective analysis of 63 cases of relapsed or refractory DLBCL patients was performed, 32 patients received conventional BACOD regimen and 31 patients received adjusted BACOD regimen., Results: The response rates for adjusted group and conventional group were 87.1%(27/31)and 62.5%(20/32), respectively, during a median follow-up of 14(7-84) months. The difference was statistically significant between the two groups (P=0.025). The main adverse events were myelosuppression, gastrointestinal adverse reactions were rarely serious, and there were no serious liver and kidney toxicity. The median overall survival (OS) was 33 months for adjusted group and 12 months for conventional group, there was statistical differences (P=0.019). The median progression free survival (PFS) was 11 months and 8 months for two groups, the difference was not statistically significant (P=0.095). 1-year survival rates were 68.8% for adjusted group and 44.3% for conventional group, there were no statistical differences (P=0.055). The expected 3- and 5-year survival rates of adjusted group were significantly higher than that of conventional group (47.1% vs 12.8%, P=0.002; 37.7% vs 8.5%, P=0.006, respectively)., Conclusion: Compared with the conventional BACOD regimen, the adjusted BCOAD regimen is effective and well tolerated in patients with relapsed or refractory DLBCL, the overall response rate and OS increased.

Objective: To establish a method for isolating and cultivating mesenchymal stem cells (MSCs) from SD rat bone marrow and to study their phenotypical and functional properties., Methods: MSCs from rat bone marrow were separated and purified by gradient centrifugation and adherence to the culture plastic; then the cells were expanded by subculture successively. The growth curves were drawn, and the morphology was observed. In an attempt to analyze immuno- and adhesive-phenotype and differentiation properties, the MSCs were evaluated with cytochemical and immunocytochemical methods., Results: MSCs belonged to the mononuclear cells of marrow, they could be isolated and purified by gradient centrifugation and adherence to the culture plastic; their living behavior was quite stable in Dulbecco's Modified Eagle's Medium with low glucose (L-DMEM) containing 100 ml/L newborn bovine serum; the growth curves of passage 1, 3 and 5 were much similar, exhibiting a 2.2-fold increase in cell number after each passage. The cells were noted to have a large expansive potential and a typical fibroblast-like morphology, and they uniformly expressed CD44, CD54, fibronectin and collagen I. When incubated in medium supplemented with dexamethasone, beta-glycerophosphate and ascorbic acid, the MSCs underwent differentiation into osteoblasts, showing positive stain of alkaline phosphatase activity and mineralized nodules., Conclusion: The cells obtained in this experiment possess phenotypical and functional properties of mesenchymal stem cells, and the method for isolating and culturing rat marrow-derived MSCs has been established.