ABSTRACT
Flow injection on-line sorption preconcentration and separation in a knotted reactor (KR) was coupled to cold vapor atomic fluorescence spectrometry for the determination of trace mercury in mineral water. Mercury was preconcentrated by on-line formation of mercury diethyldithiocarbamate complex (Hg-DDTC) and absorption of the resulting neutral complex on the inner walls of a knotted reactor. A 20%(V/V) HNO3 solution heated by electromagnetic induction heating technique was used as eluent to remove the absorbed Hg-DDTC from the KR, and then the vapor mercury generated by mixing the resulting solution and KBH4 was determined on-line by cold vapor atomic fluorescence spectrometry. The 20% HNO3 was employed as both the efficient eluent and the required acidic medium for subsequent mercury vapor generation in our work. Using 20% HNO3 instead of conventional organic solvent as eluent, the proposed method is simple, easy operational and environmentally friendly. Under the optimal experimental conditions, the sample throughput was approximatively 30/h with an enhancement factor of 35. The detection limit of mercury was 2.0 ng/L. The precision(RSD, n=11) was 2.2% at the 0.1 μg/L Hg2+ level.
ABSTRACT
Objective To study the inhibitory effect on the expression of regulated upon activation,normal T cell expressed and secreted (RANTES) and monocyte ehemotactic activity of ectopic endometrial stromal cells by nuclear factor(NF)-kB decoy oligonucleotides (ODN). Methods The stromal cells of ectopic endometrium were divided into 3 groups. Two groups were cultured with or without 10 μg/L of interleukin (IL)-1β. Another group was transfected with NF-kB decoy ODN with the aid of a lipofectamine reagent. After 4 h of transfection, 10 μg/L of IL-1β was added to induce the stromal cells to secrete RANTES. Concentration of RANTES in the supernatant at 4, 8, 12, 24 and 36 h was measured with the sandwich enzyme linked immunosorbent assay (ELISA). U937 monocyte chemotactic activity was assayed in Boyden chambers. The specific RANTES-neutralizing monoclonal antibodies at serial doses (0. 5, 1, 2, 4and 8 mg/L) were added into IL-1β induced medium of 24 h to detect the monocyte chemotactic activity of RANTES in supernatant. Results The concentration of RANTES secreted by stromal cells was respectively (58 ± 10), ( 150 ± 35 ), ( 360 ± 46 ) and ( 586 ± 42 ) ng/L after IL-1β stimulation for 8,12,24 and 36 h,significantly higher than that of stromal cells cultured without IL-1β. The concentrations of RANTES were respectively (86±16), ( 128±28 ) and ( 183±32) ng/L after IL-1β stimulation for 12, 24 and 36 h in stromal cells transfected with NF-kB decoy ODN, evidently lower than that of stromal cells stimulated with IL-1β alone. The monocyte ehemotactic index of 12, 24, 36 h in conditioned medium of stromal cells transfected with NF-kB decoy ODN was respectively 10. 3 ± 0. 9, 13.7 ± 1.1, 18.6 ± 1.2, which was evidently lower than that of stromal cells stimulated with IL-1β alone. The anti-RANTES antibody at 0. 5, 1,2, 4 and 8 mg/L inhibited respectively 5%, 23%, 40%, 62% and 61% of the chemotactic activity in 12 h medium treated with IL-1β. Conclusions RANTES accounts for the majority of the monocyte chemotactic activity in IL-1β induced medium of 24 h. NF-kB decoy ODN may influence the feed-forward inflammatory loop whereby IL-1β from activated macrophages can lead to RANTES production by ectopic implants and further monocyte chemotaxis.
ABSTRACT
Objective To evaluate the diagnostic value of sonohysterography (SHG)in uterine cavity diseases. Methods 48 patients suspected to suffer from uterine cavity diseases on the basis of transvaginal sonography underwent sonohysterography,hysteroscopy and biopsy.The results of sonohysterography were compared with those from hysteroscopy and biopsy. Results The diagnostic accuracy,sensitivity,specificity of SHG in detecting abnormal uterine cavities were 93.8%(45/48),91.4%(32/35),100%(13/13) and respectively. Conclusions SHG is a simple,effective and cheap method in the detectiou of uterine cavity diseases.