Objective:To construct and express the fusion protein between ZZ affinity peptide and alkaline phosphatase and examine its biological activities.Methods:The alkaline phosphatase gene was cloned into pEZZ 18 vector containing ZZ peptide gene resulted in the pEZZ-AP recombinant vector.Then the vector was transformed and expressed in E.coli DH5α.And HisTrap affinity chromatography was employed to separate and purify the target protein.After analyzed by Western blot , ZZ-AP fusion protein was applied to immunocytochemistry as an alterative second antibody.Results:The result of SDS-PAGE showed that the fusion protein with a relative molecular weight was consistent with the theoretical values (62 kD).The fusion protein has rabbit IgG-binding ability and en-zymatic activity of alkaline phosphatase ,those were validated in Western blot;and it produced a good signal that was comparable in its staining pattern to that generated with goat anti-rabbit IgG-AP in immunocytochemistry.Conclusion: The ZZ-AP fusion protein was constructed successfully ,it has rabbit IgG-binding ability and enzymatic activity of alkaline phosphatase.We anticipate that the ZZ-AP fusion protein has a potential application in immunoassay field.

Objective To investigate the effects of dexmedetomidine on renal function in patients with hemorrhagic shock undergoing emergency surgery.Methods Sixty patients (27 males, 33 females) with hemorrhagic shock, aged 18-69 years, ASA physical status Ⅲ or Ⅳ, required emergency surgery under general anesthesia, were randomized into two groups (n=30 each): dexmedetomidine group (group D) and control group (group C).The patients in group D receiving a loading dose of dexmedetomidine (0.5 μg/kg within 10 min) after the induction of anesthesia followed by a continuous infusion rate of 0.4 μg·kg-1·h-1 till 30 min before the end of surgery, while those in group C received equal volume of normal saline.Venous blood were obtained immediately before beginning of surgery (T1), immediately after surgery (T2), 24 h after surgery (T3) and 72 h after surgery (T4) for detecting the concentrations of the serum creatinine (Scr) and blood urea nitrogen (BUN), the contents of neutrophil gelatinase-associated lipocalin (NGAL) and high mobility group box-1 (HMGB1).The range ability of the concentration of the serum Scr from T4 to T1 (ΔScr) and the content of the serum HMGB1 from T4 to T1 (ΔHMGB1) were also calculated and recorded.Hemodynamic index (including MAP, HR) and arterial blood gas results were recorded during surgery.Results Compared with T1, MAP, CVP and BE were increased, meanwhile, HR and Lac were decreased at T2, but there was no statistically significant difference between the two groups.No statistical difference was found in BUN at any time point between group D and group C.Compared with T1, Scr decreased in both groups at T2-T4.The ΔScr in group D was higher than that in group C at T4 (P＜0.05).The content of serum NGAL at T4 in group D was significantly dropped when compared with T1 (P＜0.01) and was lower than that in group C (P＜0.05).Compared with T1, the content of serum HMGB1 was significantly decreased in both groups at T2 (P＜0.05);the content of serum HMGB1 at T3 in group C was significantly increased and was higher than that in group D;the ΔHMGB1 in group C was higher than that in group D.Conclusion Hemorrhagic shock could induce acute kidney injury.Perioperative continuous infusion of dexmedetomidine facilitated renal function recovery after ischemia-reperfusion injury in patients with hemorrhagic shock through inhibiting the elevation of serum HMGB1.

Objective:To prepare the site-specific biotinylation of enhanced green fluorescence protein with double biotin molecules using Avi-tag technology.Methods:The EGFP gene was prepared by PCR and cloned into pdi-Avitag resulting the vector pEGFP-( Avitag) 2.The fusion protein EGFP-( Avitag ) 2 was expressed in E.coli DH5αand purified by employing IMAC.The site-specific biotinylation was implemented by BirA enzyme in vitro, and then was identified by competitive ELISA and Western blot.Results:The recombinant prokaryotic expression vector pEGFP-(Avitag)2 was correctly constructed,and EGFP-(Avitag)2 fusion was successfully expressed in E.coli DH5α.The results of competitive ELISA and Western blot showed that the EGFP-( Avitag) 2 could be site-specific biotinylation with double biotin molecules based on Avi-tag technology.Conclusion: The site-specific biotinylation of EGFP with double biotin molecules is successfully prepared,and we anticipate that can be used for BAS to improve the sensitivity and specificity of immunosensors.