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.

Hyaluronic acid accelerates bone repair in human dental sockets: a randomized triple-blind clinical trial

Abstract This study evaluated the effects of hyaluronic acid (HA) on bone repair of human dental sockets. Thirty-two lower first premolars were extracted from 16 patients (2 per patient) for orthodontic reasons. Following the extractions, one socket was randomly filled with 1% HA gel, while the other was allowed to naturally fill with blood clot. After 30 and 90 days of surgery, patients underwent cone beam computed tomography. Five central orthoradial slices were captured from each socket. The gray intensity was measured in each image and results were reported as mean percentage of bone formation. The buccolingual alveolar ridge width was measured and dimensional changes were compared between the postoperative intervals. The pattern of alveolar trabecular bone was evaluated through the fractal dimension. Treated sockets showed a higher percentage of bone formation and fractal dimension values (58.17% and 1.098, respectively) compared with controls (48.97% and 1.074, respectively) in the 30-day postoperative period (p < 0.05). After 90 days, there was no significant difference between groups. Additionally, no significant difference was found between groups regarding the alveolar dimensions (p > 0.05). Use of 1% HA gel after tooth extraction accelerates bone repair in human dental sockets.

Cellular proliferation markers in peripheral and central fibromas: a comparative study

ABSTRACT Objective: To perform a comparative study of the cellular proliferation in the peripheral and central fibromas. Material and Methods: Immunohistochemistry for PCNA and the AgNOR technique were performed in 9 cases of peripheral odontogenic fibroma (POF), in 4 cases of odontogenic fibroma (OdF), in 8 cases of peripheral ossifying fibroma (PEOF) and 7 cases of ossifying fibroma (OsF). The Kruskal-Wallis and Mann-Whitney tests were used for the statistical analyses. Results: Mesenchymal component of the central lesions presented a higher mean number of AgNOR per nucleus and PCNA index than did the peripheral lesions (P≤0.05). The mean number of AgNOR per nucleus in the epithelial component proved to be higher in the OdF than in the POF (P≤0.05). The mesenchymal and epithelial components presented similar mean numbers of AgNOR per nucleus and PCNA index in the OdF, as well as a similar mean number of AgNOR per nucleus in the POF. Conclusions: The mesenchymal component may well play a role in the differences between the biological behaviour of the central lesions as compared to the peripheral lesions. Moreover, considering that the epithelial and mesenchymal components in odontogenic fibromas presented a similar proliferation index, more research is warranted to understand the true role of the epithelial components, which are believed to be inactive in nature, as well as in the development and biological behaviour of these lesions. .

Quantitative analysis of cardiac lesions in chronic canine chagasic cardiomyopathy

Lesions observed in chronic chagasic cardiopathy frequently produce electrocardiographic alterations and affect cardiac function. Through a computerized morphometrical analysis we quantified the areas occupied by cardiac muscle, connective and adipose tissues in the right atrium of dogs experimentally infected with Trypanosoma cruzi. All of the infected dogs showed chronic myocarditis with variable reduction levels of cardiac muscle, fibrosis and adipose tissue replacement. In the atrial myocardium of dogs infected with Be78 and Be62 cardiac muscle represented 34 and 50 percent, fibrosis 28 and 32 percent and adipose tissue 38 and 18 percent, respectively. The fibrosis observed was both diffuse and focal and mostly intrafascicular, either partially or completely interrupting the path of muscle bundles. Such histological alterations probably contributed to the appearance of electrocardiographic disturbances verified in 10 out 11 dogs which are also common in human chronic chagasic cardiopathy. Fibrosis was the most important microscopic occurrence found since it produces rearrangements of collagen fibers in relation to myocardiocytes which causes changes in anatomical physiognomy and mechanical behavior of the myocardium. These abnormalities can contribute to the appearance of cardiac malfunction, arrythmias and congestive cardiac insufficiency as observed in two of the analyzed dogs. Strain Be78 caused destruction of atrial cardiac muscle higher than that induced by strain Be62

Comparison of Trypanosoma cruzi infection in dogs inoculated with blood or metacyclic trypomastigotes of Berenice-62 and Berenice-78 strains via intraperitoneal and conjunctival routes

This paper aimed to verify the influence of the inoculum source (blood or metacyclic trypomastigote) and the route of inoculation (intraperitoneal or conjunctival) on the course of T. cruzi infection in dogs, using comparatively the T. cruzi strains Berenice-62 and Berenice-78. All dogs inoculated intraperitoneally became infected independently of the T. cruzi strain and source of trypomastigotes used. High level of infectivity was also observed when metacyclic trypomastigotes of both strains were inoculated by conjunctival route. However, when blood trypomastigotes were inoculated by conjunctival route the percentages of infectivity were significantly lower in dogs inoculated with both strains. Parasitaemia was significantly higher in animals infected with metacyclic trypomastigotes via the conjunctival route independently of the T. cruzi strain used. All animals infected with Berenice-78 strain showed severe acute myocarditis. On the other hand, animals infected with Berenice-62 showed severe acute myocarditis only when infected with metacyclic trypomastigote, via the intraperitoneal route. The results suggest that the source of the inoculum and the route of inoculation remarkably influence the evolution of the infection for the T. cruzi in the vertebrate host even when the same strain of the parasite is used.