The effect of preoperative irradiation and antineoplastic agents on healing at the site of bronchial anastomosis was investigated using rats. The bursting pressure in irradiation group and combined irradiation and chemotherapy group was significantly lower than in control and chemotherapy group at day 5 after operation. There was no significant difference in bursting pressure in all groups at day 7. The histologic finding of the anastomosis with H & E stain showed that submucosal connective tissue had not regenerated, and defects were seen in the submucosal tissue in irradiation and combined therapy group at day 3 and day 5. But, the connective tissue had matured in irradiation group at day 7 compared with control group. In conclusion, this study demonstrated that the healing of bronchial anastomosis was markedly delayed in early postoperative days in the rats receiving irradiation and combined therapy.
Human colorectal cancer cells were incubated with medium containing 4-methylumbelliferyl-β-D-xyloside (Xyl-MU). The cells synthesized Xyl-MU-derivatives which were detected in the culture medium by gel-filtration high-performance liquid chromatography. These included a Xyl-MU-induced glycosaminoglycan and its biosynthetic intermediates, Galβ1-4Xylβ1-MU and Galβ1-3Galβ1-4Xylβ1-MU, and other Xyl-MU-induced oligosaccharides, not related to Xyl-MU-induced glycosaminoglycan, were also synthesized. One of these oligosaccharides, sulfate-O-3GlcAβ1-4Xylβ1-MU, reacted with HNK-1, a mouse monoclonal antibody raised against human natural killer cells. Human neural cells and skin fibroblasts have also been reported to synthesize HNK-1-reactive sugar chains. Since HNK-1-reactive sugar chains are known to be involved in cell adhesion in the nervous system, the present results suggest that epithelium-derived colorectal cancer cells might also be able to utilize them in cell adhesion.
We investigated the distribution and expression of glutamate-binding protein (GBP) in the rat retinas after ischemia-reperfusion injury. Ischemia-reperfusion injury was induced in rats by clamping of the optic nerve for one hour. The distribution of GBP immunoreactivity was determined at 6, 24, 72, and 168 hours after reperfusion. Also, RT-PCR was performed to detect the change of GBP mRNA expression in the reperfused retinas. In untreated control retinas, GBP immunoreactivity was observed in the cells of ganglion cell layer, inner plexiform layer, and inner nuclear layer. At 6, 24, and 72 hours after reperfusion, GBP immunoreactivity was seen not only in the GCL, IPL, and INL, but also in the outer plexiform layer and photoreceptor outer segment. At 168 hours after reperfusion, GBP immunoreactivity in the OPL was decreased. Moreover, we found increased GBP mRNA expression at 24 hours after reperfusion. In this study, we demonstrated that ischemia-reperfusion induced increase of GBP immunoreactivity in the inner retina and increase of GBP mRNA expression in the rat retinas. Our results suggest that NMDA receptor-like complex may play some role in the ischemic cell death of the inner retina.
In recent years, the popularity of intramedullary humeral nailing is on the rise in spite of its handicaps. There are many problems in intramedullary humeral stabilization because of the anatomic structure of the bone. We performed various methods and measurements to determine shape, length and diameter and curvature of the medullary canal of the humerus in 57 human dry cadaver bones. Anterior angulation with an average of 21 cm apart from greater tubercle was found at 1/3 distal part. Mean degree of angulation was 9° (max: 15, minutes: 5, S.D.: 2.84). Humerus bones with septal aperture (supratrochlear foramen) at the fossa coronoidea were observed to have very narrow medullary canal. The best point for nail insertion was found to be an area on the line from greater tubercle anteromedially to caput humeri. This study revealed that carefully evaluated structure of humeral medullary canal and various congenital constructions such as septal aperture, and correct selection of a nail with proper length and diameter are essential for successful nailing.
Very small amount of carcinogens such as nitroso compounds and heterocyclic amines has been found in human feces. This study was designed to investigate in F344 rats whether an intrarectal noncarcinogenic small dose of n-methylnitrosourea (0.2 mg, 3 times weekly) affects colon carcinogenesis initiated with an intrarectal large dose (2 mg, 3 times weekly) of this carcinogen. The colon tumor yield at week 50 in 12 rats receiving the large dose for 2 weeks and then the small dose for the next 30 weeks significantly increased as compared to 23 rats receiving only the large dose for 2 weeks: 100% vs. 70% in tumor incidence and 4.3 vs. 1.2 in mean number of tumors per rat. No tumors were found in 12 rats receiving only the small dose for 30 weeks. The results indicate that a very small amount of carcinogens could participate in a tumor-enhancing effect on the high-risk colon induced with a large dose of carcinogens, even though their less amounts insufficient to complete carcinogenesis process. Further study is needed to elucidate if administration of such a small dose could induce epigenetic alterations or further genetic changes in the initiated colonic cells.
We examined whether differences in the location of myocardial hypertrophy influence the right ventricular diastolic function in patients with non-obstructive hypertrophic cardiomyopathy using cineangiography. Biplane right ventriculography was performed in 34 subjects (normal=14, asymmetric septal hypertrophy=9, apical hypertrophy=11) during cardiac catheterization. In patients with asymmetric septal hypertrophy, compared with apical hypertrophy and normal groups, the indices of the right ventricular diastolic function including right ventricular peak filling rate and filling fraction of rapid filling phase were lower and the time to peak filling rate was prolonged. But in patients with apical hypertrophy, these indices were not significantly different compared with normal. There were no differences in right ventricular ejection fraction and cardiac index among the three groups. These data suggest that the location of the myocardial hypertrophy of the left ventricle is a significant factor affecting the right ventricular diastolic filling in non-obstructive hypertrophic cardiomyopathy.