【Abstract】ObjectiveTo introduce a new approach for site-specific conjugation of Fab’ fragments of mouse monoclonal antibody (MoAb) to a bifunctional chelator 6-〔p-(bromoacetamido)benzyl〕-1,4,8,11 -tetraazacyclo-tetradecane-N,N′,N″,N-tetraacetic acid (BAT).MethodsFab’ fragments of B43 MoAb were obtained by a simple twostep method： 1, stable F(ab’)2 was produced by pepsin treatment of B43 MoAb. 2, Fab’ was obtained by reduction of the F(ab’)2 with cysteine. Fab’ fragments were directly conjugated with BAT. ResultsFab’ contained about 1.8 free thiol per molecule. The conjugation rate was 74% and each Fab’ fragment carried 1.28 BAT. The F(ab’)2, Fab’ and Fab’-BAT all maintained good biologic activity. ConclusionThis study may provide a simple and efficient method conjugating of MoAb Fab’ fragments to BAT.
Objective To evaluate changes of local flow field following implantation of a designed iliac venous stent. Methods Anin vitro physical model with iliocava junction was established. A modified iliac venous stent was implanted into one side and a conventional stent into the other side. The bilateral local flow fileds following implantation of stents were measured by using particle image velocimetry. Results The results of particle image velocimetry testing revealed that the main flow orientation was shifted to the right side and the region of slowly local flow was observed after implantation of conventional iliac venous stent. However, no evident changes were noted in the local flow field and no whirling flow was detected following implantation of the designed iliac venous stent. Conclusion Conventional stent is implanted into iliac vein by using a traditional technique and stent is proximal to heart and covers opening of contralateral iliac vein, which exerts certain influence upon local flow field. Local flow field has no obvious change following implantation of a designed iliac venous stent.