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M Hirota

Publications and source records attributed to M Hirota.

303 records · Page 17Linked to original sources

[Bonnoscope].

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Humans↗

Alterations of plasma immunoreactive glucagon-like peptide-1 behavior in non-insulin-dependent diabetics.

The basal level of plasma immunoreactive glucagon-like peptide-1 (IR GLP-1) was significantly elevated in non-insulin-dependent diabetics (NIDD), and this elevation of IR GLP-1 was mainly due to an increase in the large component of IR GLP-1, corresponding to the pancreatic form. During the oral glucose-tolerance test (OGTT), the total plasma IR GLP-1 decreased in normal subjects but increased significantly in diabetic patients. Chromatographic analysis showed that IR GLP-1 consisted of several different molecular forms. OGTT caused a decrease in the pancreatic form but increased the intestinal form in normal subject, resulting into a net decrease in total plasma IR GLP-1. Whereas in NIDD the increase in the intestinal form was more prominent and the suppression of the pancreatic form was practically abolished to result in a net increase of total plasma IR GLP-1. This observation is consistent with the fact that in normal subjects the total change in IR GLP-1 was significantly correlated with both the total change of gut glucagon as well as that of pancreatic glucagon, but in diabetics the total change of GLP-1 only correlated to that of gut glucagon. The impaired suppression of pancreatic GLP-1 and enhanced release of intestinal GLP-1 could have some physiological importance in NIDD.

Blood Glucose↗

The normal range of the plasma immunoreactive glucagon level during a 75 g oral glucose tolerance test.

In order to establish a normal value of plasma glucagon immunoreactivity (GI) and glucagon-like immunoreactivity (GLI) during a newly adopted 75 g OGTT, 50 normals (N), 102 individuals with IGT and 20 diabetics (D) were subjected to the OGTT, and their plasma GI and GLI levels were determined at various intervals by radioimmunoassay using 2 kinds of the C-terminal region specific antibody, OAL123 and 30K, and of the antibody specific for the N-terminal and/or central region of glucagon, OAL196, respectively. The basal levels of OAL123-GI and 30K-GI and OAL196-GLI in the 3 groups were as follows; N, 114.3, 80.8, and 335.5; IGT, 107.6, 76.1, and 338.5; and D, 135.7, 76.9, and 342.2 pg/ml. After glucose administration, a significant decrease in plasma GI and increase in plasma GLI were observed in the 3 groups, although their changes from the basal levels were variable. The plasma samples of inexplicably high GI concentration were chromatographed to clarify the nature of the hyperglucagonemia. The apparent GI was mostly eluted in the Vo component, but negligibly at the 3500 mol.wt. glucagon fraction. There was a marked difference in the Vo peak depending upon the antiserum used. These facts suggest that plasma GI values are dependent on the amount of BPG present in particular samples, and the antibody used.

Adult↗

Effect of poly(ADP-ribose) synthetase inhibitor administration to streptozotocin-induced diabetic rats on insulin and glucagon contents in their pancreas.

This study was conducted in order to clarify whether the poly(ADP-ribose) synthetase inhibitors, nicotinamide and 3-aminobenzamide, have any influence upon the content and physicochemical properties of insulin and glucagon in streptozotocin (STZ)-treated rat pancreas. STZ-treated rats received intraperitoneal injection of 350 mg/kg nicotinamide or 50 mg/kg 3-aminobenzamide 15 min before and 180 min after the administration of STZ and once a day thereafter for 23 weeks. The blood glucose levels and body weight of nicotinamide- and 3-aminobenzamide-treated rats did not differ from those of the control rats at the end of the experiment. The insulin content in poly(ADP-ribose) synthetase inhibitor-treated rat pancreas was restored partially and reached approximately 60% of the control level, while the glucagon content did not differ from that in the normal rats. Treatment with poly(ADP-ribose) synthetase inhibitor resulted in no alteration in the physicochemical properties of extracted insulin and glucagon. Immunohistological examination of the pancreas revealed that insulin- and glucagon-containing cells in the islets in the poly(ADP-ribose) synthetase inhibitor-treated rat appeared to be normalized. These results suggest that poly(ADP-ribose) synthetase inhibitor normalizes the function but not the insulin content of B cells and that it does not act on A cells in STZ-treated rat pancreas. Restoration of the insulin content would be large enough to keep the function of B cells normal.

Animals↗

Vascular encasement by pancreatic cancer: correlation of CT findings with surgical and pathologic results.

PURPOSE: The purpose of this study was to correlate thin-slice high-resolution helical CT findings of arterial and venous involvement in pancreatic cancers with surgical and histopathologic results. METHOD: Forty-eight patients with pancreatic cancer underwent preoperative thin-slice high-resolution helical CT, followed by surgical dissection of the pancreatic vessels during curative or palliative surgery. Major vessels running within 1 cm from the tumor margin were evaluated. CT appearance was graded on a 0-4 scale (0: none, 1: <24%, 2: 25-49%, 3: 50-74%, 4: 75-100%) by circumferential contiguity of tumor to vessels. Resected specimens were available from 26 patients. RESULTS: Surgical correlation of CT findings was available in 89 veins and 83 arteries, and both surgical and histologic correlation was available for 42 veins and 29 arteries. At surgical observation, 29 of 35 veins (82.9%) evaluated as CT grade 3 or 4 were found to be involved, whereas only 18 of 30 arteries (60%) evaluated as CT grade 3 or 4 were proved to be involved. On microscopic observation, tumor invasion to the portal venous systems was confirmed in 15 of 42 (35.7%) vessels, and this invasion was depicted as from CT grades 1 to 4. In arteries, tumor invasion was seen in 3 of 29 vessels (10.3%), all of which were graded as 3 or 4 by CT. CONCLUSION: The grading system of vascular invasion should differ between arteries and veins. Involvement of the venous system exceeding one-half circumference of the vessels (grade 3 or 4) was suggestive of vascular invasion; however, this criterion was not always satisfactory for the evaluation of tumor invasion in the arterial system.

Adult↗

Coronary flow reserve after coronary intervention in similar in patients with preserved viability in previous myocardial infarction and in those with angina pectoris.

The relationship between coronary flow reserve (CFR) and viability in the infarcted myocardium has not been fully clarified. We measured coronary blood flow velocity immediately after coronary intervention (with percutaneous transluminal coronary angioplasty [PTCA] or stenting) in 38 patients with previous myocardial infarction and preserved viability and 48 with angina pectoris. CFR was calculated and was similar between the two patient groups. No differences in the incidence of post-intervention CFR > 2.0 were detected; there were no differences in post-intervention CFR between patients with preserved myocardial viability and those with angina pectoris who underwent PTCA. Coronary stenting reduced the percentage diameter stenosis in both groups compared with PTCA and slightly increased the post-intervention CFR. No differences were, however, detected in post-intervention CFR between patients with preserved myocardial viability and those with angina pectoris who underwent additional stenting. These results reveal that in patients with preserved myocardial viability, post-intervention CFR was restored to values similar to those in patients with angina pectoris.

Aged↗

Chronic nephropathy in idiopathic multicentric osteolysis.

A 19-year-old girl having a sporadic form of idiopathic multicentric osteolysis with nephropathy is described. She was first diagnosed as having sporadic carpotarsal osteolysis at the age of 6. Her proteinuria was first detected at 15 years of age and renal biopsy specimens obtained at the same age were compatible with those of focal segmental glomerulosclerosis with interstitial fibrosis and tubular atrophy. Immunofluorescence microscopy revealed negative deposits of Ig G, Ig A and C3 but a trace amount of mesangial Ig M in unsclerosed segments of the glomeruli. Electronmicroscopy showed no specific changes. Renal vascular changes such as proliferation of vascular intima and medial hypertrophy were not demonstrated in the present case. It is our conclusion that focal segmental glomerulosclerosis is part of the spectrum of nephropathy in the sporadic form of idiopathic multicentric osteolysis.

Adult↗