Search

Two adult cases of non-rotation were anatomically analysed. The small intestine occupied the right flank and the colon the left. The ileum crossed the midline to enter the cecum from the right. The appendix vermiformis rested on the front of the cecum and extended upwards. The cecum was located in the lesser pelvis. They had no Ladd's bands, but in the first case fibrous bands from the posterior abdominal wall caused kinking. The colon of the first case had an intricate twist under the left kidney. The second case was also complicated with three loops, the third loop posed between the first and the second, accompanied by a rare vascular anomaly, a double inferior mesenteric artery. © 1993 Wiley-Liss, Inc.

To examine the microvascular changes of villi after transplantation, the small intestine was transplanted in 36 Wistar/Shi rats (16 syngeneic, 20 allogeneic; donor Lewis). At days 1, 4, 8, and 10, four rats of the syngeneic group and five of the allogeneic group were killed. Corrosion casts of the vessels of the graft were prepared and examined by scanning electron microscopy. In the grafts of each group at 1 day, the villous microvascular casts were reduced in height, and the capillary plexus was much less dense, with signs of degeneration. By 4 days, however, the villi of syngeneic grafts had been restored to normal, both in their dimensions and in the richness of the capillary plexus. On the other hand, the microvascular casts of allografts at the same stage showed the villi still to be greatly reduced in height, although the density of the capillary net had been restored essentially to normal. At 8 and 10 days, the allogeneic grafts again showed short villi, but with greatly reduced capillary networks, Our results suggest that the regeneration of intestinal villi following ischemic damage at operation is rapid in syngeneic grafts and that in allogeneic grafts the processes of rejection had started by 4 days. © 1992 Wiley-Liss, Inc.

The combined method injecting silicon rubber into vessels and magnifying them on a TV monitor with a video macroscope can demonstrate three-dimensional vascular structure of organs. This study compared it with a corrosion casting method observing renal glomeruli, and implied that as it is easy to prepare samples, magnifying 200 times on the TV monitor and operating the machine, students can treat it in the dissection course and in a limited schedule. It leads students to be interested in histology as well as gross anatomy, and is helpful for them to perceive human structures. © 1994 Wiley-Liss, Inc.

The splenic tissue of the rat was autotransplanted into the greater omentum to investigate the angiogenic process during splenic regeneration. Chronological observations showed the following two stages. Initially surviving subcapsular sinus endothelial cells migrated to form a preliminary vascular network, which anastomosed with ingrowing omental capillaries to form a circulatory system. In this way, splenic autotransplants would not undergo necrosis and would rapidly form endothelial and reticular cells. At a later stage, the preliminary vascular network differentiated into arteries (arterioles, capillaries), splenic sinuses, and veins. Marked morphologic changes occurred in the endothelial cells, such as vacuole formation, fenestration, and the condensation of intraendothelial microfilaments, resulting in interendothelial slits. These results showed that the formation of a preliminary vascular network caused distinct splenic regeneration and that splenic autotransplantation is a suitable model to study angiogenesis in vivo.