Cytokines and growth factors in keratinocytes and sweat glands in chronic venous leg ulcers. An immunohistochemical study

The role of growth factors and cytokines in the impaired healing of chronic leg ulcers remains uncertain. The aim of this study was to determine whether changes in the amount and location of cytokines and growth factors may be associated with impaired healing in chronic leg ulcers. Biopsies from leg ulcers of 21 patients and from normal skin of nine healthy volunteers were examined immunohistochemically for selected growth factors and cytokines. Greater staining intensity was found in keratinocytes at the edges of ulcers compared to normal skin, or skin adjacent to the ulcers. Staining at the ulcer edge was more intense in nonhealing ulcers for only vascular endothelial growth factor and platelet-derived growth factor, whereas staining in the adjacent skin was more intense for all factors in the nonhealing phase. For all factors staining was cytoplasmic, suggesting production in these areas. This study shows up-regulation of the production of cytokines and growth factors in keratinocytes of chronic leg ulcers that is greater when the ulcers are nonhealing.     

The effects of calcium channel blockers on cyclosporine and its metabolites in renal transplant recipients

Although calcium channel blockers have been reported to increase trough cyclosporine (CsA) blood levels, few studies have systematically examined the effects of calcium channel blockers on CsA pharmacokinetics. In the present investigation, complete pharmacokinetic profiles of CsA and its major metabolites (M1, M17, and M21) were determined in 11 verapamil-treated patients, 7 nifedipine-treated patients, and in 78 controls. Whole blood and urine levels were analyzed using high-performance liquid chromatography. Verapamil caused a 45% increase in CsA area under the curve, maximum concentration, steady-state concentration, and trough level. Metabolite 17 levels were increased in a parallel fashion, suggesting that altered CsA bioavailability rather than decreased metabolism may have caused the higher CsA levels in verapamil-treated patients. However, verapamil-induced reductions in CsA metabolism by other routes could not be ruled out. No changes in CsA or its metabolites were observed in nifedipine-treated patients. Unlike previous reports in patients treated with higher CsA doses, verapamil and nifedipine did not improve renal function in the present study. Nevertheless, the increase in CsA blood levels seen with verapamil may enhance the therapeutic cost-effectiveness of this agent in hypertensive renal transplant recipients.     

Influence of glucose amendment on the toxicity of two nitrophenols to Chlorella vulgaris

Glucose amendment (0.5%) to the culture medium of Chlorella vulgaris reversed the algal toxicity caused by p-nitrophenol (PNP) and m-nitrophenol (MNP), only at their algistatic levels. Algistatic and algicidal concentrations of PNP and MNP, in the absence of glucose, led to the liberation of more nitrite in the culture medium. However, addition of glucose inhibited nitrite formation.     

Hypoglycemic effect of gelatin microspheres with entrapped insulin and protease inhibitor in normal and diabetic rats

Insulin containing gelatin microspheres (IGM) with and without soyabean trypsin inhibitor (TI) were pre-pared and coated with enteric polymers to protect them from degradation in stomach and to release the insulin upon reaching the intestine. Four types of coated IGM were prepared: (i) IGM coated with natural polymers (chitosan inner coat-alginate outer coat), (ii) IGM-TI coated with cellulose acetate phthalate; (iii) IGM-TI coated with cellulose acetate butyrate, and (iv) IGM-TI coated with natural polymers (chitosan inner coat-alginate outer coat). The protective efficiency of uncoated and four types of coated microspheres to-ward digestive enzymes such as pepsin and trypsin was evaluated under simulated physiological conditions. The microspheres were characterized for their insulin content and particle size. The morphology of the micro-spheres was studied using scanning electron micros-copy. The in vitro release studies of insulin from uncoated and coated microspheres indicated that the release followed a zero-order pattern, prolonging for 6 days from 2 days in the case of uncoated spheres. The uncoated and coated microspheres containing insulin (20 IU/kg) were orally administered to albino Wistar rats by stomach tube, and insulin absorption was evaluated by assessing the hypoglycemic effect in normal and diabetic rats. A significant and continuous hypoglycemic effect was observed in diabetic rats following oral administration of coated IGM containing TI when compared to the effect following administration of coated IGM without TI.     

长春西汀片中阿朴长春胺酸乙酯含量的紫外分光光度法测定

采用紫外分光光度法测定长春丁汀片的含量。长春西汀片在２７４ｍｍ波长处有最大吸收，方法线性范围是１０－２０μｇ／ｍｌ，回归方程Ｙ＝３０．０９２Ｘ＋０．０５３３，ｒ＝０．９９９９，平均回收率为１０１．３８％（ｎ＝５，ＲＳＤ＝０．７１％）。