A Case of Occult Retroperitoneal Hematoma Associated with Head Trauma

The diagnosis and appropriate management of blunt abdominal trauma including retroperitoneal hematoma associated head injury is difficult. In our case, psoas muscle hematoma was revealed during the evaluation of fever. Psoas muscle hematoma most commonly results secondarily from coagulation defect or from retroperitoneal bleeding into the psoas sheath. The presenting signs and symptoms of this case are hypotension and anemia. Pain is also present in the back or abdomen. If it is associated with head injury and not presented massive hemorrhage, the actual diagnosis is not easy. The appropriate management depends on a careful initial evaluation including suspicion of physician, repetitive physical examination, the timely use of diagnostic procedures.

Role of Shc and phosphoinositide 3-kinase in heregulin-induced mitogenic signaling via ErbB3

ErbB3/HER3 is a cell surface receptor which belongs to the ErbB/HER subfamily of receptor protein tyrosine kinases. When expressed in NIH/3T3 cells, ErbB3 can form heterodimeric coreceptor with endogenous ErbB2. Among known intracellular effectors of the ErbB2/ErbB3 are mitogen-activated protein kinase (MAPK) and phosphoinositide (PI) 3-kinase. In the present study, we studied relative contributions of above two distinct signaling pathways to the heregulin-induced mitogenic response via activated ErbB3. For this, clonal NIH-3T3 cell lines expressing wild-type ErbB3 and ErbB3 mutants were stimulated with heregulin beta1. While cyclin D1 level was markedly high and further increased by treatment of heregulin in cells expressing wild-type ErbB3, the elimination of either Shc binding or PI 3-kinase binding lowered both levels. This result was supported by the reduction of cyclin D1 expression by preteatment with MAPK kinase inhibitor or PI 3-kinase inhibitor before stimulation with heregulin. In accordance with the cyclin D1 expression, elimination of either Shc binding or PI 3-kinase binding reduced the heregulin-induced DNA synthesis and cell growth rate. Our results obtained by the comparison of wild-type and ErbB3 mutants indicate that the full induction of the cell cycle progression through G1/S phase by ErbB3 activation is dependent on both Shc/MAPK and PI 3-kinase signal transduction pathways.

An experimental study on the microvascular anastomosis in applying the frozen arterial allograft in the rats

Although the autogenous vein graft is the most reliable in the fields of microvascular reconstruction, the microvascular allograft and microvascular prosthesis have been developed to be substitute for autogenous vein because it has many problems. In many experimental study have been reported highly variable patency rate and its thrombogenetic property of microvascular allograft. Especially, antigenicity of the homogenous vessels and immune reaction-induced thrombosis are main cause of homogenous microvascular anastomosis failure. For that reason, several investigators have attempted to reduce the antigenicity and improve the patency rate of microvascular allograft. The purpose of this study was to observe the healing process in applying frozen arterial allograft in the rats. In order to perform this study, 27 Sprague-Dawley rats, weighing 300gm or more selected. 12 carotid arterial anastomoses were performed in the rats by using microvascular end-to-end anastomosis as control group and 15 frozen(-196degreesC) arterial allografts were implanted into the carotid artery in the rats by using microvascular anastomosis as experimental group. The experimental rats were sacrificed on the 1st, 3rd, 7th, 14th, 28th, 56th day after operations. For scanning electron microscopic study, fixation was performed by perfusion of 2.5% glutaraldehyed-2% paraformaldehyed in 0.1M phosphate buffer at pH7.3. The specimens were post-fixated in 1% osmium tetraoxide for 2 hours, washed with cacodylate buffer, dehydrated in a series of ascending ethanol baths, critical point dried, coated with gold in a vacuum evaporator, and observed with a scanning electron microscope(JEOL, JSM-840-A, 20kV). For histologic examination taken specimens were embedded in paraffin, sectioned 6-8micrometer in thickness. The specimens were stained with hematoxylin-eosin stain method, examined under light microscope. The results were as follows; 1. The patency rate of control group was 92% and experimental group was 86%. 2. Endothelial cells regeneration at the anastomosis site of both group was partially appeared on the 1st week after experiment. 3. On the 2nd week after experiment, anastomosis site was completely covered with regenerated endothelial cell in both group, and the endothelial cell proliferated toward the graft at experimental group. 4. On the 4th, 8th week after experiment, the grafted artery was partially covered with endothelial cell at experimental group.