Pentoxifylline and electromagnetic field improved bone fracture healing in rats.

BACKGROUND: The aim of this study was to evaluate the effects of a phosphodiesterase inhibitor pentoxifylline (PTX), electromagnetic fields (EMFs), and a mixture of both materials on bone fracture healing in a rat model. MATERIALS AND METHODS: Eighty male Wistar rats were randomly divided into four groups: Group A, femur fracture model with no treatment; Group B, femur fracture model treated with PTX 50 mg/kg/day intraperitoneal injection; Group C, femur fracture model treated with EMF 1.5±0.2 Mt/50 Hz/6 hours/day; and Group D, femur fracture model treated with PTX 50 mg/kg/day intraperitoneal injection and EMF 1.5±0.2 Mt/50 Hz/6 hours/day. RESULTS: Bone fracture healing was significantly better in Group B and Group C compared to Group A (P<0.05), but Group D did not show better bone fracture healing than Group A (P>0.05). CONCLUSION: It can be concluded that both a specific EMF and PTX had a positive effect on bone fracture healing but when used in combination, may not be beneficial.

Total relaxivities of material content in various cysts and ameloblastoma: implications for discriminating different fluids.

Nuclear magnetic resonance T(1) and T(2) relaxivities (r(1) and r(2)) exhibit efficiency of a material to alter the relaxation rates (1/T(1) and 1/T(2)), and they are being used for diagnostic purposes. The determination of total relaxivities (r(1t) and r(2t)) of cystic fluid content and ameloblastoma may therefore be useful for discriminative purposes. In order to determine what makes total relaxivities of hemorrhagic cysts, four sets of tubes containing pooled cyst were doped with increasing concentrations of iron, copper, albumin, and gamma-globulins. These sets were replaced in a phantom together with six individual cysts and one ameloblastoma. The relaxation times were measured by magnetic resonance imaging operating at 1.5 T. The relaxivities of individual ions and proteins were determined from the slope of the relation between relaxation rates and concentration, while total relaxivities were determined by using the increases in relaxation rates and material content of cystic fluid (MC). Iron, copper, albumin, and gamma-globulins were found to be the sources of r(1t) and r(2t). Each of r(1t), r(2t), r(1t)MC, r(2t)MC, and r(2t)/r(1t) are distinctive parameters for each cystic category and ameloblastoma. Except for MC, the parameters measured for ameloblastoma are significantly smaller than those of cysts. The similarity of the present results to those used in clinical applications suggests that each of r(1t), r(2t), r(1t)MC, r(2t)MC, and r(2t)/r(1t) has an ability to discriminate various fluids and masses. The present work also suggests that r(1t)MC, r(2t)MC, and r(2t)/r(1t) can be determined in vivo.