Activation of nuclear factor-kappa B and its modulalorg effects on intercellular adhesion molecule-1 expression in mice with dextran sulphate sodium-induced rat colitis / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the changes in the activity of nuclear factor-kappaB (NF-kappa B) in mice with dextran sulphate sodium (DSS)-induced rat colitis and its modulalorg effect on intercellular adhesion molecule-1 (ICAM-1) expression.</p><p><b>METHODS</b>Twenty normal male mice were randomized into DSS group and normal saline (NS) control group according to a matched-pair design. From days 1 to 7, the mice in DSS group were subjected to oral administration of 5%DSS solution, and from days 8 to 20, NS was given instead, for a total of 3 cycles. In the control group, only NS was administered. The colonic pathology was observed using HE staining and the mucosa 1 damage was scored for each mouse. The DNA-binding activity of NF-kappa B was tested by electrophoretic mobility shift assay, and the expressions of ICAM-1 and NF-kappa B p65 were detected using immunohistochemistry.</p><p><b>RESULTS</b>The DNA-binding activity of NF-kappa B was significantly increased in DSS group as compared with NS group. ICAM-1 and p65 expressions were detected in the nuclei of the vascular endothelial and inflammatory cells, especially in the mucosa and submucosa, but such positive cells were seldom observed in NS group. A positive correlation was found between the DNA-binding activity of NF-kappa B and ICAM-1 expression.</p><p><b>CONCLUSION</b>NF-kappa B activation is an important event in the development of DSS-induced colitis in that activated NF-kappa B upregulates ICAM-1 expression during colonic inflammation.</p>

Preparation of enteric microsphere of oleanolic acid dihemiphthalate sodium by salting-out action using spherical crystallization technique / 药学学报

<p><b>AIM</b>Enteric microspheres were prepared to prevent the interaction of drug with gastric acid and to improve its bioavailability.</p><p><b>METHODS</b>The enteric microspheres with a matrix structure were successfully produced using a spherical crystallization technique. Hydroxypropyl methylcellulose phthalate (HP-55), an enteric material, was coprecipitated with the drug by salting-out effect during the preparation process. A mixture of water and ethanol was chosen as a good solvent and dichloromethane was used as a bridging agent while 0.1 mol x L(-1) sodium chloride solution was selected as a poor solvent.</p><p><b>RESULTS</b>It is the first time to prepare microspheres by making the water-soluble drug and water-insoluble excipient coprecipitated. In vivo test demonstrated that the drug absorption from the enteric oleanolic acid dihemiphthalate sodium (OADHPS) microspheres was significantly prolonged compared to that with OADHPS powder after a lag-time. Furthermore, the drug bioavailability was 181.6% greater than that with the OADHPS powder.</p><p><b>CONCLUSION</b>The microspheres of water soluble drug could be prepared by using water phase replacing organic phase as poor solvent which decrease the quantity of organic solvent and benefit the environment prevention.</p>

Evaluation of in vitro/in vivo correlation for three kinds of self-designed sustained-release nitrendipine formulations using deconvolution method / 药学学报

<p><b>AIM</b>To evaluate the in vitro/in vivo correlation for three kinds of self-designed sustained-release nitrendipine formulations using deconvolution method.</p><p><b>METHODS</b>The characteristics of in vivo release were calculated by deconvolution method using the data of plasma concentration of three kinds of self-designed sustained-release nitrendipine formulations in healthy dogs, in which the in vivo results of nitrendipine solution after oral administrated to dogs were used as weight function. It was the compared with characteristics of in vitro release to assess the in vitro/in vivo correlations.</p><p><b>RESULTS</b>The good correlations of in vitro/in vivo were shown in three kinds of self-designed sustained-release nitrendipine formulations using deconvolution method.</p><p><b>CONCLUSION</b>The deconvolution method exhibited advantage in evaluation of in vitro/in vivo correlation for self-designed sustained-release nitrendipine formulations.</p>

Preparation of sustained-release nitrendipine microspheres with a solid dispersed structure in liquid system / 药学学报

<p><b>AIM</b>To prepare the sustained-release nitrendipine microspheres with a solid dispersed structure in liquid system.</p><p><b>METHODS</b>The sustained-release nitrendipine microspheres with a solid dispersed structure was prepared in liquid system by combining spherical crystallization technique and solvent deposition method in one step. The resultant microspheres were evaluated for the recovery, micromeritc properties, incorporation efficiency. The factors of effect on the formation and the release rate of microspheres were also investigated.</p><p><b>RESULTS</b>The recovery of microspheres (280-900 microns) was more than 70% and the bulk density was around 0.7 kg.L-1. The incorporation efficiency always exceeded 95%. The formation of microspheres was mainly affected by the amount of bridging liquid and the emulsifying agents in poor solvent. The release rate of nitrendipine from the microspheres could be controlled as desired by adjusting the ratio of talc to Eudragit RS PO in the formulation.</p><p><b>CONCLUSION</b>The presented method was suitable for preparing sustained-release microspheres of a water insoluble drug.</p>