Search PubMed⌕ Search

Biomedical subjects

M Imamura

Publications and source records attributed to M Imamura.

At least 739 records · Page 41Linked to original sources
PubMed1982

Identification of lymphocyte subpopulations in human breast cancer tissue and its significance: an immunoperoxidase study with anti-human T- and B-cell sera.

Subpopulations of the infiltrating lymphocytes in breast cancer tissue from 31 patients were identified by indirect immunoperoxidase technique with antihuman T- and B-cell sera. In all noncancerous lesions examined (seven cases), B-cells were predominant and T-cells were scarcely found. In contrast, T-cells were predominant in breast cancer tissues (17 in 21 cases). T-cells tended to contact closely with cancer cells or cancer cell nests and accumulated around and in the walls of venules draining the cancer, while B-cells tended to cluster focally apart from cancer cell nests. T-cell infiltration was scanty in scirrhus carcinoma, whereas it was ample in infiltrating papillotubular carcinoma which had a better prognosis. There was a significant reverse correlation between the intensity of the T-cell infiltration and the clinical stages. The intensity of the T cell infiltration was significantly high in patients without lymph node metastasis. These facts suggest the possibility that the infiltrating T-cells in cancer tissue represent host resistance against cancer and that the intensity of the T cell infiltration correlates with the clinical prognosis of the breast cancer patients.

Adenocarcinoma, Papillary↗
PubMed1982

Altered properties of tumors induced by adenovirus type 12 DNA fragment transformed cells after growth in immunocompetent rats.

The GY1-3-1 cell line, which was derived from a rat cell line transformed by the Ad 12 HindIII-G fragment, can induce tumors in newborn rats but not in mature rats. However, when 10 mature rats were transplanted with a large number of GY1-3-1 tumor fragments, two developed tumors with a long latency period. These two tumors (GY1-3M and GY1-3Y) were quite different in properties from the originally inoculated GY1-3-1 tumor. Tumor transplantation studies revealed that both GY1-3M and GY1-3Y tumors could grow in mature rats and the number of takes with transplanted tumor was 100% with GY1-3M tumor and 40% with GY1-3Y tumor. Histopathologically original GY1-3-1 tumor showed a morphology of undifferentiated sarcoma, while the histologic picture of GY1-3M and GY1-3Y tumors was similar to that encountered in human fibrosarcoma and malignant fibrous histiocytoma, respectively. Both GY1-3M and GY1-3Y tumors, when recultured in vitro, gave rise to cell lines with a fibroblastic appearance although the original GY1-3-1 cell line exhibited an epithelioid morphology. In chromosome analysis, the GY1-3-1 cell line was pseudodiploid, while the cell lines from GY1-3M and GY1-3Y tumors were hyperdiploid or near-triploid. The metacentric marker chromosome, MI, was present in mitotic cells of the GY1-3-1 line and of the GY1-3M tumor lines, but absent from the GY1-3Y tumor lines. By Southern blot hybridization, multiple bands of cellular DNAs from parental GY1-3-1 cells hybridized with labelled Ad 12 HindIII-G, while only a single band hybridized DNAs from both GY1-3M and GY1-3Y tumors.

Adenoviruses, Human↗
PubMed1982

Gastrin release from gastrinoma cells stimulated with secretin.

The secretin injection test has been proved to be useful in the diagnosis of gastrinoma in vivo. Fresh gastrinoma cells were cultured for a short time in vitro and then stimulated with secretin. A rise in the gastrin concentration in the culture medium was observed within 10 min after the addition of secretin. This fact may be evidence that gastrinoma cells have receptors which bind with secretin resulting in the release of gastrin.

Cells, Cultured↗
PubMed1982

Cancer of the pancreas with hyperamylasemia.

A 66-yr-old woman had several attacks resembling relapsing acute pancreatitis with elevation of serum amylase for about three months. Obstruction of the main pancreatic duct was detected with endoscopic retrograde pancreatoductography, though no abnormality was revealed on celiac and mesenteric arteriograms. At that time she had no jaundice. Laparotomy revealed a walnut-sized tumor in the head of the pancreas compressing the main pancreatic duct. Pancreaticoduodenectomy was performed. The pathological diagnosis of the tumor was well-differentiated papillary cysto-adenocarcinoma of the pancreas. She had no attack of hyperamylasemia since the operation, and is well 2 years after the surgery. Close attention to persistent elevation of pancreatic amylase levels in serum and urine would enhance the chance of detection of small pancreatic cancers before the development of jaundice.

Aged↗
PubMed1982

Effect of biliary reconstruction procedures on gastric acid secretion.

In 26 patients with Roux-Y choledochojejunostomy and 10 with jejunal interposition choledochoduodenostomy, gastrin-stimulated gastric acid secretion and serum levels of gastrin and secretin after feeding were examined before operation and at the time of follow-up. The follow-up levels of maximum acid output were higher than those before operation in each group, and they tended to be higher in patients with Roux-Y choledochojejunostomy (Group I) than in those with jejunal interposition choledochoduodenostomy (Group II), but the difference was not significant. There was no instance of postoperative peptic ulcer in either group. The levels of serum gastrin after feeding tended to be higher in Group II, whereas serum secretin levels were contrarily higher in Group I. The changes in these hormones could be considered not as the cause but rather as the outcome of the changes in postoperative gastric acid secretion.

Adult↗
PubMed1982

Lysozyme dimer formation on lysozyme oxidation with Br2 radical as studied by fluorescence evolution.

Lysozyme dimers produced on oxidation of lysozyme with Br2 radical in aqueous solutions exhibit a fluorescence spectrum (lambda max = 400 nm) closely similar to that of bi-tyrosine. This suggests that the dimer is likely to have a tyrosine-tyrosine bond resulting from the combination of tyrosine phenoxy radicals of two lysozyme molecules. Kinetic studies on dimer formation were made by measuring time-dependent fluorescence after pulsed-electron irradiation over wide pH range. The results lead to the following conclusions. The second-order growth of the dimer fluorescence observed at pH 10.7-12.5 reflects the combination process of the lysozyme radicals, which is rate-determining in the pH range. On the other hand, the first-order growth observed at pH 6.8-10.2 is attributable to the enolization of the keto-form of the dimer. A tentative reaction scheme is proposed for the dimer formation.

Bromides↗
PubMed1982

Surgical treatment for Crohn's disease, with special reference to operative procedures and their relationship to recurrence.

Of 14 patients with Crohn's disease, 12 to whom operation was performed at our department were studied with regard to operative procedures and their relationship to recurrence. The following results were obtained: 1) Resection of the intestinal lesions was performed in all patients. The recurrence rate was as high as 42% (5 of 12 cases). 2) If the length of the normal intestine resected was more than 10 cm, there was no correlation between the length of the resection and recurrence of the disease. 3) The postoperative recurrence rate tended to decrease by means of regional lymph nodes dissection. From these results, it is concluded that the recommendable operative procedures for Crohn's disease are intestinal resection including the normal intestine more than 10 cm in length and regional lymph nodes dissection.

Adolescent↗
PubMed1982

An ultrastructural study of subacute necrotizing lymphadenitis.

Fifteen cases of a unique lymphadenitis called subacute necrotizing lymphadenitis were studied electron-microscopically. The large lymphoreticular cells proliferating at cortical or paracortical areas of the lymph nodes mainly consisted of immunoblasts and histiocytoid cells, which were characterized by numerous intracytoplasmic myelinlike inclusions. Such histiocytoid cells seemed to be derived from the immunoblasts. Tubuloreticular structures, which had been often noticed within endothelial cells or lymphocytes of the patients with systemic lupus erythematosus (SLE) or SLE-related diseases, were also observed with high frequency in most cases examined. They were present within the cytoplasm of immunoblasts, endothelial cells, and histiocytoid cells. Immunoblasts in mitosis occasionally contained these structures. We offer the hypothesis that subacute necrotizing lymphadenitis with still unknown etiology may reflect a self-limited SLE-like autoimmune condition induced by virus-infected transformed lymphocytes.

Adolescent↗
PubMed1981

The oxidation of ferrocytochrome c by Br2-, (SCN)2-, N3 and OH radicals studied by pulsed-electron and gamma-ray radiolysis.

The reactions of ferrocytochrome c with Br2-, (SCN)2-, N3 and OH radicals were followed by measuring the change in the optical spectra of cytochrome c on gamma-irradiation as well as the rate of change of absorbance upon pulse irradiation. Ferrocytochrome c is oxidized to ferricytochrome c by Br2-, (SCN)2- or N3 radical with an efficiency of about 100% through a second-order process in which no intermediates were observed. The rate constants in neutral solutions at I = 0.073 are 9.7 . 10(8) M-1 . s-1, 7.9 . 10(8) M-1, 1.3 . 10(9) M-1 . s-1 for the oxidation by Br2-, (SCN)2- and N3 radicals, respectively. The rate constants do not vary appreciably in alkaline solutions (pH 8.9). The ionic strength dependence was observed for the rate constants of the oxidation by br2- and (SCN)2-. Those rate constants estimated on the assumption that the radicals react only with the amino acid residues with the characteristic steric correction factors were less than one-tenth of the observed ones. These results suggest that the partially exposed region of the heme is the probable site of electron transfer from ferrocytochrome c to the radical. Hydroxyl radicals also oxidize ferrocytochrome c with a high rate constant (k greater than 1 . 10(10) M-1 . s-1), but with a very small efficiency (5%).

Animals↗
PubMed1981

Gastric acid secretion and serum gastrin levels in chronic pancreatitis.

Of 114 patients with chronic pancreatitis, 19 (16.7%) has gastric or duodenal ulcers. Patients with moderate pancreatic exocrine dysfunction tended to show high acid output and low serum gastrin levels, while those with severe dysfunction had slightly lower acid output and higher serum gastrin levels. The higher the degree of pancreatic fibrosis, the higher tended to be the acid output and serum gastrin levels. Not all patients with ulcers developed hypergastrinemia. The mechanism of acid hypersecretion and ulcer formation in patients with chronic pancreatitis cannot be explained solely by pancreatic deterioration, fibrosis or gastrin release; a decrease in the production and release of gastric inhibitory hormone should be taken into consideration.

Chronic Disease↗
PubMed1981

Arthrogryposis multiplex congenita: an autopsy case of a fatal form.

A case of a severe and fatal form of arthrogryposis multiplex congenita with a full necropsy examination is presented in which the central nervous system and many muscles of the four extremities were examined histologically. The most striking feature was a great reduction in the muscular tissue of the limbs with a marked increase in the adipose tissue. The muscular changes were thought to be caused by neurogenic atrophy, and microscopy of the spinal cord revealed developmental abnormalities, including degenerative changes of the anterior horn cells. Neonatal and fatal cases of arthrogryposis multiplex congenita reported in the literature are briefly reviewed, and the characteristics of the present case and its relation to other congenital neuromuscular disorders are discussed.

Adipose Tissue↗
PubMed1981

Dimer formation in radiation-irradiated aqueous solution of lysozyme studied by light-scattering-intensity measurement.

The reaction of lysozyme with OH., Br.-2 and e-aq, produced in an aqueous solution by pulsed electrons and gamma-rays, were investigated. Irradiated enzymes showed an increase in the light scattering intensity (LSI) which is proportional to the absorbed dose. Results obtained from SDS gel electrophoresis confirm dimerization of lysozyme, which is considered to be responsible for the increase in LSI. It was found that the rate constant of the dimerization of protein radicals produced in the reaction with OH. is 2K=(1.0 +/- 0.3) X 10(6)M-1 s-1 and the yield of the dimerization is 0.6 in G. The enzymatic activity of the dimer is shown to be reduced to about 30 per cent of that of the intact enzyme. It is concluded that the radiation-induced inactivation of lysozyme is largely due to dimerization.

Electrons↗