Objective To investigate the effect of erythropoietin (EPO) on vascular endothelial cell apoptosis induced by homocysteine (Hcy) and the role of nuclear factor-κB (NF-κB) p65.Methods Human umbilical vein endothelial cells (HUVECs) were divided into normal control,Hcy treatment,EPO pretreatment,and simple EPO groups.The cell viability was detected by the methylthiazolyl tetrazolium (MTT) assay,the apoptosis rate was measured by flow cytometry,and the expression of NF-κB p65 was tested by Western blot.Results The apoptosis rates in the groups of the normal control,Hcy treatment,EPO pretreatment and simple EPO (all n =3) were 2.23 ± 0.4％,12.8 ± 1.2％,3.2 ± 0.5％ and 2.18 ± 0.6％,respectively (F =1 105.630,P =0.000).The apoptosis rate in the Hcy treatment goup was significantly higher than that in the normal control group (P =0.000) ; there was no significant differences between the simple EPO group and the normal control group (P =0.616); the apoptosis rates in the groups of EPO pretreatment (P =0.000) and simple EPO (P =0.000) were significantly lower than that in the Hcy treatment group.Western blot analysis showed that the normal control group almost did not express NF-κB p65.The expression of NF-κB p65 in the groups of Hcy treatment,simple EPO and EPO pretreatment (all n =3) were 66.1 ± 7.3,1 046.1 ± 71.3 and 1 362.4 ± 25.3,respectively.There were significant differences among the 3 groups (F =1 310.954,P =0.000).The expression of NF-κB p65 in the groups of EPO pretreatment (P =0.000) and simple EPO (P=0.000) were significantly higher than that in the HCY group.The expression of NF-κB p65 in the EPO pretreatment group was significantly higher than that in the simple EPO group (P =0.007).Conelusions EPO may attenuate Hcy-induced endothelial cell apoptosis via upregulating the expression of NF-κB p65.

To develop a specific, rapid, and convenient immunochromatography assay (ICA) to detect melamine residues in dairy products and feed sample. Colloidal gold particles labeled with purified monoclonal antibody against anti-melamine were used as the detector reagent. The MEL-OVA (the conjugate of melamine and ovalbumin) and goat anti-mouse melamine IgG were blotted on the test and control regions of nitrocellulose membrane. The strip was then assembled with sample pad, absorbing pad, and dorsal shield. The limit of detection (LOD) is 50 microg/L. The test trip was applied to detect melamine in milk, milk powder, and animal feeds, with detection limits of 100 microg/L for milk, 100 ng/g for milk powder, 200 ng/g for feeds. Compared to LC-MS/MS, the ICA could be used to screen a large number of dairy products and feed samples for melamine residue.
Animals ; Antibodies, Monoclonal ; chemistry ; Cattle ; Dairy Products ; analysis ; Food Contamination ; analysis ; Gold Colloid ; chemistry ; Immunochromatography ; methods ; Milk ; chemistry ; Reagent Strips ; chemical synthesis ; chemistry ; Sensitivity and Specificity ; Triazines ; analysis