Experimental study of replacement of an esophageal segment with an nitinol alloy composite artificial esophagus / 中华外科杂志

<p><b>OBJECTIVE</b>To observe the feasibility of a segment thoracic esophagus replaced by using a nitinol alloy composite artificial esophagus.</p><p><b>METHODS</b>A nitinol alloy composite artificial esophagus was made of a nitinol tube coated with a silicone membrane with a dacron flange 1 cm proximal to each end. There were ten pigs for the models of experimental animal. The models of experimental animal were established by excised a segment of 7 cm long thoracic esophagus and replaced with the graft. In accordance with the different anastomosis connective way 10 pigs were divided into group I and group II, every group had 5 pigs. In group I monolayer end-to-end anastomosis was used with this prosthesis. In group II monolayer end-to-end anastomosis was used with this prosthesis and above the site of anastomosis adding dacron strip fixed. After operation the operate animals were observed for eating and health. Esophagography and flexible esophagoscopy were performed once a month at the first, second, and third postoperatively month. Three pigs of the grafted prostheses sloughed out spontaneously at different postoperatively period were killed for autopsy and pathologic examination of the neoesophagus.</p><p><b>RESULTS</b>All pigs had no leakage at the site of anastomosis and survived over 6 months. The longest survival was 20 months. Seven of 10 pigs the grafted prostheses sloughed out spontaneously at 2 to 6 months after the operation (4 in group I and 3 in group II). The grafted prostheses sloughed out spontaneously less than 3 months after operation, marked neoesophageal stenosis in the grafted portion was recognized (3 in group I). They displayed serious difficulty in eating. But the prostheses sloughed out spontaneously more than 3 months after operation, neoesophageal stenosis was increased slightly and the stenosis was only temporary and gradually resolved. (1 in group I, 3 in group II) They lived in good health and without difficulty in eating. Three of 10 pigs the grafted prosthesis still stayed in the grafted place over 10 months (1 in group I, 2 in group II). The neoesophageal had no stenosis. They were perfectly well in eating.</p><p><b>CONCLUSIONS</b>A segment excised pig esophagus replaced with a nitinol alloy composite artificial esophagus is feasible and takes a better result.</p>

Effects of intragastric administration of thenorphine on morphine-induced behavioral sensitization in mice / 药学学报

<p><b>AIM</b>To investigate the effects of intragastric administration of thenorphine (Then) on behavioral sensitization to morphine (Mor) in mice.</p><p><b>METHODS</b>Locomotor activity was detected after intragastric administration of thenorphine or co-administration of thenorphine with Mor in mice. Mice were induced to be behaviorally sensitive to Mor, and were given the combination of Mor and thenorphine to observe the effects of thenorphine on the development, transfer and expression of Mor-induced behavioral sensitization.</p><p><b>RESULTS</b>A single intragastric administration of thenorphine (1.25 - 5.0 mg x kg(-1)) dose-dependently inhibited the locomotor activity in mice (P < 0.01) and the effects of thenorphine on locomotor activity developed tolerance after repeated administration. Co-administration of thenorphine effectively inhibited Mor-induced hyperactivity (P < 0.05) and the development, transfer, expression of Mor-induced behavioral sensitization in mice (P < 0.05 or P < 0.01).</p><p><b>CONCLUSION</b>Thenorphine was shown to suppress the central nervous system and may be effective against the abuse and addiction to opioids.</p>