We investigated the ability of anti-ICAM-1 monoclonal antibodies to reduce endothelial cell damage by assessing microvascular permeability and microcirculatory function during the acute phase of allograft rejection. The composite rat hindlimb-cremaster muscle transplantation model was employed in three experimental groups of 18 animals each. Isograft control transplantations were performed between genetically identical Lewis (LEW, RT11) rats. Allograft transplantations were performed across a major histocompatibility barrier between Lewis-Brown-Norway (LBN, RT-11+n), and Lewis (LEW, RT11) rats. In addition, a third group of animals receiving allografts was treated with 1 mg/kg/day of anti-ICAM-1 monoclonal antibody. After 24 hours, 72 hours, and 7 days, we measured microvascular permeability, leukocyte activation, functional capillary perfusion, red blood cell velocity, vessel diameters, and endothelial edema index in six animals per each follow-up period. Endothelial cell damage was assessed by measuring graft permeability to fluorescein isothiocyanate-labeled albumin (0.2 ml/100 g body weight) with computer-aided image analysis. Mean microvascular permeability was lower in the treated allograft group than in untreated controls at all follow-up times (p<0.001). In addition, anti-ICAM-1 treatment significantly reduced the activation of sticking leukocytes at 24 and 72 hours (p<0.001) and the activation of transmigrating leukocytes at 72 hours and 7 days (p<0.05). The allografts presented a characteristic microcirculatory pattern of acute rejection as early as 24 hours after transplantation. The dysfunction of the endothelial cell barrier at all time points was indicated by significant increases in the degree of allograft macromolecular permeability and in the number of activated sticking and transmigrating leukocytes. Treatment with anti-ICAM-1 antibodies significantly reduced the surge of leukocytes in the allograft transplants and protected the endothelial barrier from the acute effects of transplantation trauma.

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This study was designed to investigate the effect of dehydroepiandrosterone (DHEA) on the recovery of the rat sciatic nerve following crush injury. A standard hemostat system was used to create the injury, with a length of 1.5 mm in three groups of 18 animals each. In group I, the crush injury was applied without any treatment. In groups II and III, vehicle (ethylene glycol) and DHEA solutions were injected subepineurally 30 min following the crush injury. Sciatic function index (SFI), toe contracture measurement, gastrocinemius muscle weight, total number of myelinated fibers, fiber diameters, myelin thickness, and axon/fiber cross-sectional ratio were measured at 3, 6, and 12 weeks. The SFI values in the DHEA group showed a faster return to normal values confirmed at 3 and 6 weeks (P < 0.05). The number of myelinated fibers and fiber diameters at 6 and 12 weeks were significantly higher in the DHEA group (P < 0.05). In this study, the subepineural injection of DHEA following crush injury was found to enhance functional recovery of the rat sciatic nerve.

The authors investigated the reliability of the safe area, which previously was defined to prevent injury to the superior gluteal nerve during the lateral approach to the hip, and its relation to body height. The distance between the point of entry of the superior gluteal nerve into the gluteus medius muscle and the greater trochanter, in the regions which were defined as the anterior and posterior halves of the muscle, were measured in 23 cadaveric hips. There was a significant correlation between the height of the cadavers and the distance in the anterior and posterior regions. In all of the anterior regions and 78% of the posterior regions of the hips, the superior gluteal nerve as found to be in the safe area. The current study showed that the average distance between the innervation point of the gluteus medius muscle and the greater trochanter might change as a function of body height. The risk of damage to the superior gluteal nerve may be higher if the direct lateral approach to the hip is used. These data show that it is possible that the safe area is not always safe.