Biomedical subjects
A Miyoshi
Publications and source records attributed to A Miyoshi.
VIPergic innervation of diabetic pancreas in rats.
Morphological, ultrastructural, and immunocytochemical studies of nerves containing vasoactive intestinal peptide (VIP) are described in diabetic pancreas of rats after streptozotocin treatment. The observations covered 48 hours and 6 months following streptozotocin treatment. At the ultrastructural level, degenerative changes were already observed in axons of nerve ganglia in the pancreas 48 hours (early stage) after streptozotocin treatment. These changes were hardly detected at the light microscopic level and VIP-like immunoreactivities were seen in nerves and fibers in such pancreas. The nerve ganglia were almost absent in the diabetic pancreas 6 months after streptozotocin treatment (late stage). Associated with the absence of nerve ganglia, nerves and fibers containing VIP-like immunoreactivities were also absent at this late stage. The findings indicated that the changes in the diabetic pancreas were neuropathic caused by metabolic disturbance after long standing diabetes and resulting absence of VIP-like immunoreactive nerves occurred. It was suggested from the present study that the changes in nerve ganglia began as damage at the ultrastructural level due to acute toxicity of the chemical at an early stage and then developed destruction and absence at a late stage.
The age-related difference in bone changes in rats induced by recombinant human granulocyte colony-stimulating factor.
We examined the bone changes in recombinant granulocyte colon-stimulating factor (rhG-CSF)-treated young and young adult rats in order to investigate the effect of age-related conditions of bone growth on the bone changes induced by rhG-CSF. Recombinant human G-CSF (100 and 1,000 micrograms/kg/day) was given to rats by daily intravenous injection for 28 days starting at the age of either 6 or 14 wk, and the hindlimb bones were evaluated histopathologically. In the young rats, bone lesions were observed in the 100- and 1,000-micrograms/k groups. In the young adult rats, lesions were found only in the 1,000-micrograms/kg group. The lesions involved accelerated osteoclastic bone resorption and osteogenesis due to intramembranous ossification and there was no age-related difference in these histopathological findings. However, both the incidence of bone involvement and the severity of lesions were greater in the young rats than in the dose-matched young adult rats. The results suggest that the higher dose of rhG-CSF may intrinsically induce bone lesions of a particular histopathological nature in rats regardless of their age, and the action of rhG-CSF on bone may be stronger in young growing rats than in young adults.
Posterior hepatic duct injury during laparoscopic cholecystectomy finally necessitating hepatic resection: case report.
A case of bile duct injury during laparoscopic cholecystectomy finally necessitating right hepatic lobectomy is reported to re-emphasize the importance of preoperative and intraoperative assessment of the biliary tree. A 47-year-old Japanese woman underwent laparoscopic cholecystectomy for cholecystolithiasis. On postoperative day 5, fever and right hypochondralgia developed, and CT revealed fluid collection at the right hypochondrium. Percutaneous drainage was performed, and subsequent fistulography revealed a communication of the cystic cavity with the right posterior bile duct, which suggested injury of the aberrant hepatic duct. Conservative therapy, including the adaptation of fibrin glue, was performed, but closure of the fistula and cavity was not obtainable. Finally, a right hepatic lobectomy was performed four months after cholecystectomy. In this case, endoscopic retrograde cholangiopancreatography was unsuccessful preoperatively, and intraoperative cholangiography was not done. This case report re-emphasizes that the preoperative and intraoperative examination of the biliary tree is mandatory to avoid bile duct injury.
Stimulation by gastro-intestinal hormones of cyclic adenosine 3': 5'-monophosphate accumulation and insulin release in isolated pancreatic islets of the rat.
In collagenase isolated rat pancreatic islets, CCK-PZ, SHG, secretin and glucagon stimulated the accumulation of cAMP, in physiological ranges. The resulting increment of cAMP showed a good correlation with insulin release stimulated by either glucagon or secretin, but not by SHG or CCK-PZ. In the same system, 14CO2 production from glucose-U-14C was significantly increased by either SHG or CCK-PZ. The results presented in this report are compatible with the hypothesis that insulin release by gastrointestinal hormones may be mediated by cAMP in the B-cell in the case of either glucagon or secretin; whereas, in the case of either SHG or CCK-PZ, it may presumably be mediated by an unknown mechanism in glucose metabolism, other than c-AMP.
[Studies on the gastric inhibitory substance in human saliva (salivogastrone). 1. Experimental studies].
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Effect of chenodeoxycholic acid and its conjugates on cholesterol gallstone dissolution in hamsters.
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