A catalytic spectrophotometric method for determination of trace molybdenum by flow injection analysis has been established, based on the catalytic oxidation of potassium iodide by hydrogen peroxide in the presence of molybedenum (VI) and the iodine produced is coloured with starch. The linear range and detection limit for molybdenum (VI) were 0 to 0.4 ppm and 3.2 ppb. The method has been successfully applied to determine molybdenum in the grain, soil and hair.

AIM:To set up a determination of tanshinone Ⅱ_A and cryptotanshinone in Compound Danshen Tablet(Radix Salviae Miltiorrhizae, Radix Notoginseng, Borneolum Syntheticum) by RP-HPLC. METHODS:Two components could be separated through YWG-C_~18 column with methanol-water (75∶25 by volume) as a mobile phase. The flow rate was 1.0 mL?min~-1 , and the detection wavelength was at 270 nm. RESULTS: The linear range of tanshinone Ⅱ_A and cryptotanshinone were 2.5-50.0 ?g?mL~-1 and 0.625-12.5 ?g?mL~-1 , respectively. The average recovery was 99.76% with RSD 0.92% for tanshinone Ⅱ_A and 98.34% with RSD 0.71% for cryptotanshinone, respectively. CONCLUSION: The method is simple, accurate and rapid with good reproducibility. It can be used for the quality control of Compound Danshen Tablet.

Objective To explore a new peptide-based approach independent of HLA to generate antigen-specific CD+ CD8+T cells. Methods Peripheral blood mononuclear cells(PBMC) were stimula- ted for 6 h with IE-1 peptide pool. Then the activated IFN-γsecreting ceils were tested by immunomagnetic selection. And the selected cells were cultured with radio-inactivated PBMC in medium with 100 IU/ml IL-2 for 4 weeks. Results The generated T cell lines consisted of IE-1 specific CD4+ T (6.88%) and CD8+ T cells 92.99%, which demonstrated antigen-specific killing and cytokine secretion. Conclusion T ceils can be proliferated with this new procedure, and maintain its phenotype and antigen-specific function.

AIM: To analyze the capability of cytomegaIovirus (CMV)-infected human embryonic lung fibroblasts (HELFs) to induce immune response. METHODS: HELFs were infected with cytomegalovirus and stained with antibody against HLA-A2 molecular, the expression of HLA-A2 was detected by FCM. The infected HELFs were incubated with individual pp65 peptide NLVPMVATV. While the uninfected and unloaded infected HELFs served as control respectively. After PBMC was added to the differently treated HELFs and incubated, the immune response was measured with IFN-γ release as readout. RESULTS: The expression of HLA-A molecular on infected fibroblasts diminished markedly compared with that on the uninfected. The peptides expressed on the infected HELFs together with those pulsed externally induced a stronger response than the infected HELFs alone. CONCLUSION: Although CMV can downregulate the expression of MHC Ⅰ on the infected cells, it can not decrease the capacity of cells to present peptides loaded externally, and therefore still induce immune response to some extent.

Objective To investigate the influence of interferon-a therapy on CD8 T memory subsets in patients with chronic hepatitis B(CHB) and correlation between the effect of IFN-α and CD8 T memory subsets. Methods Blood samples from 57 patients with CHB were collected before treatment (0 week), at 12 weeks and 24 weeks of treatment with pegylated IFN-α. Assays were performed on freshly isolated peripheral blood mononuclear cells ( PBMCs). For phenotype analysis, All data were acquired on a flow cytometer instrument and prepared for analysis. Results A significantly higher frequency of CD8+ TEM and lower frequency of CD8+ TCM in inactive HBsAg carriers than that in CHB patients prior to treatment was observed (P <0.05). The proportion of CD8 + TCM was higher in group nonresponders than in group respond-ers, and the proportion of CD8 + TEM was lower in group nonresponders than in group responders (P < 0.05 ). The average dosage of IFN-α applied to patients with response was significantly higher than nonresponders. Conclusion The dominance of circulating effector memory T cells may be associated with elimination of viral infection, and possibly benefit for response to therapy with IFN-α.