Objective To observe the effect of β-amyloid42 (Aβ42) on stimulating the inflammatory factors production by BV-2 microglia, including interleukin-1β (IL-1β), IL-10 and nitric oxide (NO), and to contrast the inhibitory action of anti-Aβ42 antibody in serum of Alzheimer's patients and the artificially synthesized anti-Aβ42 antibody. Methods The anti-Aβ42 antibodies were extracted from the serum of Alzheimer's patients. And the BV-2 microglia cells in murine were cultured as in vitro cell model. The cells were stimulated by Aβ42 and the two different anti-Aβ42antibodies to analyze the impact of stimulants on the cell activity. The Aβ42 of 5 μmol/L was added to the culture separately or in mixture with each of the two different anti-Aβ42 antibodies. Each antibody was mixed with Aβ42 of 5 μmol/L at final anti-Aβ42 antibody titre of 5 μg/ml, 1 μg/ml and 0.2 μg/ml,respectively. Then clear supernatant was collected from each tube respectively at 6 h, 12 h, and 24 h after culture, and the concentrations of IL-1β, IL-10 and NO were determined. Results The Aβ42,artificially synthesized anti-Aβ42 antibody and anti-Aβ42 antibody from Alzheimer's patients had no effects on the activities of BV-2 cells, the cell survival rates were (98. 6±5.8)%, (101.9±2.8)%and (98. 4±6.0)%, with no significant differences as compared with normal control group (F=0. 407, P＞0. 05). The inflammatory factors releasing from BV-2 cells stimulated by Aβ42 reached the peak level at 12 h, the concentrations of IL-1β, IL-10 and NO were (69.0±12.7) pg/ml, (24.1 ±4. 0) pg/ml and (128. 2±8. 7) μmol/L, the concentrations of IL-1β and NO were significantly higher at 12 h than at 6 h and 24 h (F= 15. 470 and 242. 107, P＜0.05), there was no significant difference in the concentration of IL-10 among 12 h, 6 h and 24 h (F=1. 852, P＞0.05). The two different antiAβ42 antibodies of different titre remarkably inhibited Aβ42 stimulated BV-2 cells to release inflammatory factors. At high titre of 5 μg/ml, the two different antibodies showed no significant difference in the inhibitory effects (P＞0.05), while at the titre of 0. 2 μg/ml, anti-Aβ42 antibody from Alzheimer's patients showed a significantly lower inhibitory effect than artificially synthesized antibodies, the concentrations of NO were (35.4 ± 2. 5) μoml/L and ( 19. 2 ± 3.3) μoml/L,respectively (P ＜ 0.05). Conclusions The Aβ42 can stimulate BV-2 microglia cells to release inflammatory factors. Anti-Aβ42 antibody from Alzheimer's patients has a lower inhibitory effect on Aβ42 in stimulating microglia to release inflammatory factors.

An analytical method of on-line injection technique including on-line dilution and on-line preconcentration with inductively coupled plasma mass spectrometry ( ICP-MS ) was established for the determination of trace metals in seawater, such as Cr, Mo, Cu, Pb, Zn, Cd, Fe, Mn, Ni, V, Co. This method could automatically make standard curves and match matrix, and by the on-line dilution and preconcentration modes, 11 trace metals could be analyzed directly. With high-level automation, CASS-5 and NASS-6 seawater standard samples were analyzed accurately by this method. The recovery of metals in seawater sample addition was between 80% and 115%. The method quantitation limits (μg/L ) of theses metals in seawater were 0. 06(Cr), 0. 06(Mo), 0. 01(Cu), 0. 005(Pb), 0. 01(Zn), 0. 006(Cd), 0. 03 (Fe), 0. 02(Mn), 0. 01(Ni), 0. 01(V), and 0. 01 (Co), respectively. This method was applied to analyze seawater samples of various salinities in Zhejiang coast, and the analysis results were consistent with results of conventional atomic absorption method.