SUBJECTS: Female Dark Agouti (DA) rats.
METHODS: Three different dosages of (2 mg/kg of body weight, 3 mg/kg of body weight and 4 mg/kg of body weight) collagen and complete Freund's adjuvant suspension were tested. After 45 days, serum C-reactive protein, TNF-α, superoxide dismutase and total glutathione assays were done. Radiographic and histopathological changes in the joints were compared.
RESULTS: All three groups showed signs of arthritic changes, confirmed by histopathological and radiographic changes. Severe arthritic changes were seen in the rats injected with 4 mg/kg of body weight of collagen. There was a significant increase in C-reactive protein, TNF-α, super oxide dismutase and total glutathione levels in the plasma in arthritis rats and the changes were more significant with 4 mg/kg of collagen.
CONCLUSION: These results demonstrated that the optimal dose to inject to experimental animals in order to get server arthritic changes was 4 mg/kg of collagen with complete Freund's adjuvant suspension. Severe arthritis changes induced significant elevation in plasma C-reactive protein and TNF-α levels.
Methods: The matrix patches were prepared by using different polymers, with and without silicone adhesive, dibutyl sebacate and mupirocin. The patches were characterized for mechanical properties, drug content, moisture content, water absorption capacity and Fourier transform infrared spectrum. In vitro release studies were performed by using Franz diffusion cell. In vitro disk diffusion assay was performed on the Mueller-Hinton Agar plate to measure the zone of inhibition of the patches. The in vivo study was performed on four groups of rats with bacterial counts at three different time intervals, along with skin irritancy and histopathologic studies.
Results: The patches showed appropriate average thickness (0.63-1.12 mm), tensile strength (5.08-10.08 MPa) and modulus of elasticity (21.53-42.19 MPa). The drug content ranged from 94.5% to 97.4%, while the moisture content and water absorption capacities at two relative humidities (75% and 93%) were in the range of 1.082-3.139 and 1.287-4.148 wt%, respectively. Fourier transform infrared spectra showed that there were no significant interactions between the polymer and the drug. The highest percentage of drug release at 8 hours was 47.94%. The highest zone of inhibition obtained was 28.3 mm against S. aureus. The in vivo studies showed that the bacterial colonies were fewer at 1 cm (7×101 CFU/mL) than at 2 cm (1.3×102 CFU/mL) over a 24-hour period. The patches were nonirritant to the skin, and histopathologic results also showed no toxic or damaging effects to the skin.
Conclusion: The in vitro and in vivo studies indicated that controlled release patches reduced the migration of S. aureus on the live rat skin effectively, however, a longer duration of study is required to determine the effectiveness of the patch on a suitable peritonitis-induced animal model.