Objective To study the influence of brominated furanones on the biofilm formation of Escherichia coli on the polyvinyl chloride (PVC) material, and to provide new ideas for the research of surface modification of materials and cl inicaltreatment of biomaterial centered infection. Methods Three brominated furanones with representative chemical structurewere chosen and coated on the surface modification of PVC materials, respectively [furanone 1: 3, 4-dibromo-5-hydroxy-furanone; furanone 2: 4-bromo-5-(4-methoxyphenyl)-3-(methylamino)-furanone; furanone 3: 3, 4-dibromo-5, 5-bis (4-methylphenyl)- 2 (5H)-furanone]. All the modificated PVC materials and Escherichia coli were co-cultivated. The PVC material soaked with 75% ethanol for 5 minutes and Escherichia coli were co-cultivated together as the control group. The thickness of bacterial community and bacterial community quantity in the unit area on PVC materials were measured by confocal laser scanning microscope (CLSM), and the surface structure of biofilm formation was observed by scanning electron microscope (SEM). Results The CLSM showed that the thickness of bacterial community and the bacterial community quantity in the unit area of PVC materials was significantly less (P lt; 0.05) in furanone 3 group than in control group, but no significant difference (P gt; 0.05) was found between furanone 1, furanone 2 groups and control group. SEM showed that the quantity of bacterial community in the unit area of PVC materials surface in furanone 3 group was fewer than that in control group at 6 hours; the biofilm structure on PVC materials surface formed at 18 hours in control group, furanone 1 group, and furanone 2 group, but there was no mature biofilm structure on PVC materials surface in furanone 3 group at 18 hours. Conclusion The impact of different brominated furanones on Escherichia coli biofilm formation on the surface of PVC materials is different, 3, 4-dibromo-5, 5-bis (4-methylphenyl)-2 (5H)- furanone can inhibit Escherichia coli biofilm formation on the surface of PVC material.
Abstract: Objective To investigate the effect of cytokineinduced killer (CIK) cells immunotherapy on immunity function of non-small cell lung cancer (NSCLC) patients after operation. Methods Fifty patients with histological or cytological diagnosis of NSCLC on Ⅰstage,Ⅱstage andⅢa stage of tumor, nodes, metastasisclassification were randomly divided CIK cells therapy group and conventional therapy group, 25 cases each group. The immunity function of patients with NSCLC, including the levels of CD3+, CD4+ T cells, ratio of CD4+/CD8+, natural killer(NK) cells, and the levels of Th1/Th2 cytokine were detected before treatment, and the 2nd, 4th, 8th week after treatment. Results The levels of CD3+, CD4+ T cells, NK cells, ratio of CD4+/CD8+, interleukin-2(IL-2), interferon-γ(INF-γ) in CIK cells therapy group at the 2nd week after treatment were more higher than those before treatment (Plt;0.01), their levels reached the peak at 4th week, from then on, it began to decrease. Meanwhile, the levels of Th2 of CIK cells therapy group began to decrease at the 2nd week after treatment, a low ebb at 4th week. At the 2nd, 4th and 8th week,the levels of CD3+,CD4+ T cells, ratio of CD4+/CD8+, NK cells,IL-2, INF-γ, interleukin-4(IL-4), interleukin-10(IL-10) of CIK cells therapy group compared with those inconventional therapy group,there were statistical significance difference［(Plt;0.05),at 4th week after treatment, CD3+ 70.2%±9.1% vs.46.3%±5.8%; CD4+40.2%±7.1% vs.22.9%±4.5%; CD4+/CD8+ 1.82±0.43 vs. 1.09±0.34; NK 15.7%±5.4% vs.10.5%±2.5%; IL-2 34.8±11.7 ng/L vs. 19.8±12.1 ng/L; INF-γ63.7±23.3 ng/Lvs. 30.8±10.6 ng/L; IL-4 10.2±8.6 ng/L vs. 25.8±6.3 ng/L; IL-10 10.6±3.4 ng/L vs. 21.4±8.6 ng/L］. Conclusion The results indicate that CIK cells immunotherapy can enhance the immune function of NSCLC patients after operation.
ObjectiveTo explore the influence of three central venous catheter biomedical materials (polyurethane, silicone, and polyvinyl chloride) on the proliferation, apoptosis, and cell cycle of Xuanwei Lung Cancer-05 (XWLC-05) cells so as to provide the basis for clinical choice of central venous catheter. MethodsXWLC-05 cells were cultured and subcultured, and the cells at passage 3 were cultured with polyurethane, silicone, and polyvinyl chloride (1.0 cm × 1.0 cm in size), and only cells served as a control. At 24, 48, and 72 hours after cultured, MTT assay was used to detect the cellular proliferation and flow cytometry to detect the cell cycle and apoptosis. At 72 hours after cultured, inverted microscope was used to observe the cell growth. ResultsInverted microscope showed the cells grew well in control group, polyurethane group, and silicone group. In polyvinyl chloride group, the cells decreased, necrosed, and dissolved; residual adherent cells had morphologic deformity and decreased transmittance. At 24 and 48 hours, no significant difference in proliferation, apoptosis, and cell cycle was found among 4 groups (P gt; 0.05). At 72 hours, the proliferations of XWLC-05 cells in three material groups were significantly inhibited when compared with control group (P lt; 0.05), and the cells in polyvinyl chloride group had more significant proliferation inhibition than polyurethane group and silicone group (P lt; 0.05), but there was no signifcant difference in proliferation inhibition between polyurethane group and silicone group (P gt; 0.05). Compared with the control group, three material groups had significant impact on the rate of apoptosis and cell cycle: polyvinyl chloride group was the most remarkable, followed by silicone group, polyurethane group was minimum (P lt; 0.05). ConclusionPolyvinyl chloride can significantly impact the proliferation, apoptosis, and cell cycle of XWLC-05 cells; polyurethane has better biocompatibility than polyvinyl chloride and silicone
ObjectiveTo study the effect of intercellular adhesion (ica) operon of Staphylococcus epidermidis on the inflammation associated with mixed biofilm of Staphylococcus epidermidis and Candida albicans on endotracheal tube material in rabbits. MethodsThe standard strains of Staphylococcus epidermidis RP62A (ica operon positive, positive group) and ATCC12228 (ica operon negative, negative group) were taken to prepare a bacterial solution with a concentration of 1×106 CFU/mL, respectively. Then, the two bacterial solutions were mixed with the standard strain of Candida albicans ATCC10231 of the same concentration to prepare a mixed culture solution at a ratio of 1∶1, respectively. The mixed culture solution was incubated with endotracheal tube material for 24 hours. The formation of mixed biofilm on the surface of the material was observed by scanning electron microscope. Thirty New Zealand rabbits, aged 4-6 months, were divided into two groups (n=15), and the endotracheal tube materials of the positive group and the negative group that were incubated for 24 hours were implanted beside the trachea. The body mass of rabbits in the two groups was measured before operation and at 1, 3, and 7 days after operation. At 1, 3, and 7 days after operation, the levels of interleukin 1β (IL-1β), IL-6, tumor necrosis factor α (TNF-α), and monocytechemotactic protein 1 (MCP-1) were detected by using an ELISA test kit. At 7 days after operation, the formation of mixed biofilm on the surface of the endotracheal tube materials was observed by scanning electron microscope, the inflammation and infiltration of tissues around the materials were observed by HE staining, and the bacterial infections in heart, lung, liver, and kidney were observed by plate colony counting method.ResultsScanning electron microscope observation showed that the mixed biofilm structure was obvious in the positive group after 24 hours in vitro incubation, but no mixed biofilm formation was observed in the negative group. In vivo studies showed that there was no significant difference in body mass between the two groups before operation and at 1, 3, and 7 days after operation (P>0.05). Compared with the negative group, the levels of MCP-1 and IL-1β at 1 day, and the levels of IL-1β, MCP-1, IL-6, and TNF-α at 3 and 7 days in the positive group all increased, with significant differences (P<0.05). Scanning electron microscope observation showed that a large amount of Staphylococcus epidermis and mixed biofilm structure were observed in the positive group, and a very small amount of bacteria was observed in the negative group with no mixed biofilm structure. HE staining of surrounding tissue showed inflammatory cell infiltration in both groups, and neutrophils and lymphocytes were more in the positive group than in the negative group. There was no significant difference in the number of bacterial infections in heart and liver between the two groups (P>0.05). The number of bacterial infections in lung and kidney in the positive group was higher than that in negative group (P<0.05).ConclusionIn the mixed infection of Staphylococcus epidermidis and Candida albicans, the ica operon may strengthen the structure of the biofilm and the spread of the biofilm in vivo, leading to increased inflammatory factors, and the bacteria are difficult to remove and persist.