ABSTRACT
BACKGROUND:The patients are suffering from peritoneal adhesions that are caused after abdominal operation. As so far, there is stil no effective drug or method that can completely prevent peritoneal adhesions. Carboxymethyl chitosan is a biocompatible and biodegradable biomedical material with anti-adhesion effects, which is an ideal biomaterial for prevention of peritoneal adhesion theoreticaly. OBJECTIVE:To investigate the novel anti-adhesion properties of carboxymethyl chitosan anti-adhesion solution on the prevention of postsurgical adhesion in vivo in a rat model. METHODS:Fifty-six adult male Wistar rats were randomly divided into four groups: 0.9% normal saline solution (group A), hyaluronic acid gels (group B), medical chitosan gels (group C) and carboxymethyl chitosan anti-adhesion solution (group D). The model of postoperative intestinal adhesion was established by making cecal scratches/abdominal wal defects. Al the rats were scarified after 2 or 3 weeks. Whole blood was colected by cardio-puncture, lung tissue and tissue adhesion were stripped. The incidence and degree of adhesions, histological effects, expression of transforming growth factor-β1 (TGF-β1), the amounts of hydroxyproline and white blood cels were observed. RESULTS AND CONCLUSION:The formation of postsurgical adhesions in groups B, C and D was significantly decreased, which was lighter than that of group A (P < 0.05). Furthermore, the adhesion formation in group D was significantly decreased in comparison with group A (P < 0.01). At the same time, the levels of transforming growth factor-β1, hydroxyproline and white blood cels in group D were lighter than those of group A (P < 0.05), and the histopathological results indicated that a marked reduction in inflammatory cels and fibroblasts. Carboxymethyl chitosan anti-adhesion solution can effectively reduce the degree and incidence of postoperative adhesion, and it is becoming a promising drug delivery system in the context of postsurgical anti-adhesion.
ABSTRACT
Aim: To explore the in situ intestinal absorption in rats of ZLR-8, an insoluble NO-donor drug, and to compare the intestinal absorption enhancement by spray-dried emulsion. Methods: Intestine of rats was cannulat-ed for in situ perfusion. UV and HPLC methods were used to monitor phenolsulfonphthalein and ZLR-8, respec-tively. The effects on ZLR-8 absorption of the intestinal segments, the concentration of ZLR-8 and the pH of the circulating perfusate were studied. The absorption of ZLR-8 suspension was compared to that of the spray-dried emulsion. Results: 1-h in situ intestinal perfusion of the spray-dried emulsion allowed the estimation of the absor-tion percentage to be (23. 54 ± 1. 40) %, (15. 95 ± 0. 09) %, (12. 30 ± 0. 74) %, (3. 98 ± 0. 12) %, respec-tively; the absorption rate constants in duodenum, colon, jejunum and ileum to be (0.248 6 ±0.046 0) h~(-1), (0. 143 7 ±0. 036 0) h~(-1), (0. 069 2 ±0. 001 3) h~(-1), (0. 020 8 ±0. 000 4) h~(-1), respectively. Significant differ-ences in absorption characteristics were found among intestinal segments. In the range of 3. 4-9. 4, pH of the per-fuate had significant influence on the absorption of ZLR-8, and better absorption appeared at pH of 5. 4 to 7. 4. It was found that the absorption rate constant was unaffected by ZLR-8 concentration. However, the absorption amount was proportional to ZLR-8 concentration. Compared to the ZLR-8 suspension, the in situ intestinal absorption of ZLR-8 in rats given the spray-dried emulsion increased significantly. Conclusion: It was only found that ZLR-8 administered in suspension has minor absorption in rat duodenum while no apparent absorption occurred in other segemnts. ZLR-8 in spray-dried emulsion was fairly absorbed in the rat intestinal segments. Passive diffusion was invloved in the absorption of ZLR-8. Spray-dried emulsion significantly enhanced the intestinal absorption of ZLR-8 in rats.
ABSTRACT
Objective:Optimising the technological parameters for the extraction of Maxingshigan Decoction (Herba Ephedrae, Semen Pruni Armeniacae, Gypsum Fibrosum, Radix Glycyrrhizae). Methods:Using the even design and TCL, ephedrine, glycyrrhetinic acid, hydrocyanic acid, calciumion and extract weight were taken as the indexes. Results:Optimal parameters: the pH values of the water for the 1st, 2nd and 3rd decoctions are 2.0 ,6.5 and 9.0,respectively; and the time of 3 decoctions are 2.0,1.0and 0.5h, respectively. Conclusion:Optimal parameters for Maximpshipan Decoction are feasible in extraction.