Evaluation of mesalazine polymeric conjugate in the treatment of actinic proctitis in rats

ABSTRACT Purpose: The present study aimed at testing a new formulation of mesalazine linked to chondroitin sulfate and its components alone in the treatment of actinic proctitis in rats. Methods: Forty-seven female Wistar rats were submitted to pelvic radiation and divided into eight groups: control A, mesalazine A, chondroitin A, and conjugate A, gavage of the according substance two weeks after irradiation and sacrifice three weeks after oral treatment; control C, mesalazine C, chondroitin C, and conjugate C, sacrifice six weeks after oral treatment. The rectum was submitted to histological characterization for each of the findings: inflammatory infiltrate, epithelial degeneration, mucosal necrosis, and fibrosis. Results: The inflammatory infiltrate was more intense in chondroitin A, mesalazine A, and conjugate C. The collagen deposition was less intense in chondroitin A, and mesalazine A, and more intense in control C. Conclusions: Mesalazine and chondroitin alone were efficacious in inducing a delayed inflammatory response, hence reducing the late fibrosis. The conjugate was able to induce an ever more delayed inflammatory response.

Development and validation of analytical method by HPLC-DAD for determination of vasodilator active in pharmaceutical ophthalmic forms

The substance 4-Aminobenzamidine dihydrochloride (4-AD) is one of the degradation products of diminazene aceturate and has demonstrated antiglaucomatous potential. Glaucoma is the second leading cause of blindness worldwide; thus, new therapeutic alternatives must be studied, for example, the molecule 4-AD vehiculated into polymeric inserts for prolonged release. The present work aims to develop and validate an analytical method to quantify 4-AD in pharmaceutical ophthalmic forms. A HPLC was used with UV-Vis detector, at 290 ƞm and ACE® C18 column (125 × 4.6 mm, 5 µm), in which the mobile phase consists of phosphate buffer (pH 7.4) and triethylamine (30 mmol/L), under an isocratic flow of 1.0 mL/min. The retention time of 3.2 minutes was observed. The method was developed and validated in accordance with ANVISA recommendations and ICH guides. The linearity range was established between the concentrations 5 and 25 µg/mL (correlation coefficient r = 0.993). The accuracy, repeatability, and intermediate precision tests obtained a relative standard deviation less than or equal to 5%. In addition, the method was considered selective, exact. and robust, with pH being its critical factor. Therefore, the HPLC analysis method is robust and can be used to quantify 4-AD in pharmaceutical forms for ocular application.(AU)

Prevention of bone infection after open fracture using a chitosan with ciprofloxacin implant in animal model

Abstract Purpose To evaluate different concentrations of ciprofloxacin to prevent infection after open fracture contaminated with S. aureus in rats using absorbable local delivery system. Methods Fifty-two Wistar rats were assigned to six groups. After 4 weeks, all animals underwent 99mTc-ceftizoxima scintigraphy evaluation, callus formation measurement and histological analysis. ANOVA, t-Student and Kruskal Wallis were used for quantitative variables statistical analysis, whereas qui square and exact Fisher were used for qualitative variables. Results Treatment using 25% and 50% of ciprofloxacin incorporated at the fracture fixation device were effective in preventing bone infection compared to control group (p<0.05). Chitosan were not effective in preventing bone infection when used alone compared to control group (p>0.05). Histological findings demonstrated bone-healing delay with 50% of ciprofloxacin. No difference in callus formation were observed (p>0.05). Conclusion Local delivery treatment for contaminated open fracture using chitosan with ciprofloxacin is effective above 25%.

New delivery systems for amphotericin B applied to the improvement of leishmaniasis treatment

Leishmaniasis is one of the six major tropical diseases targeted by the World Health Organization. It is a life-threatening disease of medical, social and economic importance in endemic areas. No vaccine is yet available for human use, and chemotherapy presents several problems. Pentavalent antimonials have been the drugs of choice to treat the disease for more than six decades; however, they exhibit high toxicity and are not indicated for children, for pregnant or breastfeeding women or for chronically ill patients. Amphotericin B (AmpB) is a second-line drug, and although it has been increasingly used to treat visceral leishmaniasis (VL), its clinical use has been hampered due to its high toxicity. This review focuses on the development and in vivo usage of new delivery systems for AmpB that aim to decrease its toxicity without altering its therapeutic efficacy. These new formulations, when adjusted with regard to their production costs, may be considered new drug delivery systems that promise to improve the treatment of leishmaniasis, by reducing the side effects and the number of doses while permitting a satisfactory cost-benefit ratio.