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Biomedical subjects

M Noguchi

Publications and source records attributed to M Noguchi.

At least 649 records · Page 36Linked to original sources
PubMed1986

GRF neurons in the rat hypothalamus.

The growth hormone-releasing factor (GRF)-containing neuronal system was immunohistochemically studied in the rat hypothalamus. The immunolabeled cell bodies were determined by intraventricular administration of colchicine 24 h before killing. In intact animals, the neurons appeared in the ventral portion of the arcuate nucleus (group 1) and in the area surrounding the ventromedial nucleus (group 2). Most of the cell bodies also indicated immunoreactivity for tyrosine hydroxylase (TH). The immunoreactive fibers accumulated showing a palisade arrangement in the external layer of the median eminence. The rats treated neonatally with monosodium glutamate revealed group 2 neurons and a few immunoreactive fibers in the median eminence. Half-anterolateral deafferentation of the medial basal hypothalamus, which was performed to isolate group 1 neurons or both group 1 and 2 neurons from the other brain parts, did not remarkably affect the appearance of the fibers in the median eminence. However, the perikarya were hypertrophic and strongly immunolabeled for GRF and TH. It is concluded that the fibers containing GRF in the median eminence derive mostly from group 1 neurons, and that the neurons may be regulated by an inhibitory mechanism by other neurons on the outside of the deafferented hypothalamic islands. GRF synthesized in group 2 neurons may act on other neurons as a neurotransmitter-like substance.

Animals↗
PubMed1986

Activation of adipocyte adenylate cyclase by protein kinase C.

Adenylate cyclase activity in purified rat adipocyte membranes is stimulated by the calcium- and phospholipid-dependent enzyme protein kinase C. Over the concentration range of 100-1000 milliunits/ml, both highly purified (approximately 3000 units/mg of protein) protein kinase C from rat brain and partially purified (14 units/mg of protein) protein kinase C from guinea pig pancreas stimulate cyclase activity. The actions of both protein kinase C preparations on adenylate cyclase activity are dependent on added calcium, which is effective at concentrations less than 10 microM. Exogenous phospholipids are not required for stimulation of adenylate cyclase by protein kinase C; but, under typical cyclase assay conditions, the adipocyte membranes satisfy the lipid requirement for protein kinase C phosphorylation of histone. The tumor-promoting phorbol ester 12-O-tetradecanoylphorbol-13-acetate enhances the kinase action on cyclase, and the phorbol ester is effective at concentrations equimolar with the kinase (less than 10 nM). With the brain protein kinase C, 12-O-tetradecanoylphorbol-13-acetate effects are especially evident at limiting calcium concentrations. Inhibitors of protein kinase C activity, such as chlorpromazine, palmitoylcarnitine, and polymyxin B, inhibit selectively that adenylate cyclase activity which is stimulated by protein kinase C plus calcium. It is concluded that protein kinase C acts directly on the adipocyte adenylate cyclase system.

Adenylyl Cyclases↗
PubMed1986

Effect of calcium deficiency on the content of nonreducible crosslinks in rat mandibular bone.

The effect of calcium deficiency on the content of the nonreducible cross-linking amino acid, pyridinoline, in rat mandibular bone was studied. An apparent decrease in serum and bone calcium levels was observed beginning at four weeks after initiation of a calcium-deficient diet. The pyridinoline content in the bone of calcium-deficient animals began to increase at four weeks and thereafter increased markedly as compared to that of controls. Collagen content increased significantly six weeks after calcium deficiency. These results suggest that calcium deficiency inhibits mineralization and promotes the formation of pyridinoline in rat mandibular bone.

Amino Acids↗
PubMed1986

Immunoperoxidase investigation of Regan isoenzyme of alkaline phosphatase in maxillary sinus carcinomas.

The Regan isoenzyme of alkaline phosphatase is known to be produced ectopically by various malignant tumors. To assess whether this isoenzyme is expressed in maxillary sinus carcinomas, immunostaining for Regan isoenzyme was carried out on 35 maxillary sinus carcinomas comprising 27 squamous cell carcinomas, 6 adenocarcinomas, and 2 adenoid cystic carcinomas. The enzyme was shown to be present in 11 of 27 cases of squamous cell carcinoma, 2 of 6 cases of adenocarcinoma, and 1 of 2 cases of adenoid cystic carcinoma. Regan isoenzyme was identified in the cytoplasm and/or cell membrane of squamous cell carcinoma cells, whereas it was demonstrated mainly on the luminal membrane and in the secretions of both adenocarcinoma and adenoid cystic carcinoma cells. These findings show that Regan isoenzyme does, indeed, occur in maxillary sinus carcinomas.

Adenocarcinoma↗
PubMed1986

Generation of cytotoxic T lymphocyte responses to allo-H-2 antigens in allogeneic bone marrow chimeras histocompatible at the H-2 subregions.

The present study was performed to determine whether H-2 matching is required for full cytotoxic T lymphocyte (CTL) responses to allo-H-2 antigens in allogeneic bone marrow chimeric mice. A number of irradiated, bone marrow-reconstituted chimeras constructed from various combinations of marrow cells from B10 H-2 recombinant strains and AKR recipient mice were prepared. Spleen cells obtained from such chimeras and normal control mice were activated in vitro by culturing them with irradiated stimulator cells. It was shown that spleen cells from [4R----AKR], [(4R X 3R)F1----AKR] or [AQR----AKR] chimeras, which were histocompatible on the left hand-side of the H-21 subregion between donor and recipient mice, generated greater CTL activities than those that were seen with spleen cells of [3R----AKR] or [5R----AKR] chimeras, which were histoincompatible in this region. We were unable to demonstrate suppressor cell activity of the spleen cells of [3R----AKR] chimeras cultured with stimulator cells. Although spleen cells from [3R----AKR] chimeras showed substantial proliferative responses to stimulator cells (MLR) and to Con A and LPS, IL2 activities of supernatants from Con A-activated spleen cells (Con A SN) of the chimeras were significantly lower than those of [4R----AKR] or [(4R X 3R)F1----AKR] chimeras. Furthermore, vigorous CTL activities were obtained with either spleen cells or thymocytes from [3R----AKR] chimeras when rat Con A SN was added to the MLR cultures. These observations suggest that the numbers of precursor CTLs in the cells from [3R----AKR] chimeras are at the same level as those of [(4R X 3R)F1----AKR] or normal mice and that the low CTL activities generated by spleen cells of [3R----AKR] chimeras compared to H-2I-matched chimeras are due in large measure to deficiency in IL2 production by the splenic T cells of the [3R----AKR] chimeras.

Animals↗
PubMed1986

Papillary adenoma of type 2 pneumocytes.

A case of papillary adenoma of type 2 pneumocytes is reported. A 57-year-old man had an unusual coin lesion in the periphery of the right lung without any symptoms. When detected in a mass survey examination, it was approximately 1.5 cm in diameter, well circumscribed, and located in S4, involving the sixth-order bronchus of B4. Light-microscopic examination revealed cuboidal tumor cells arranged in a papillary pattern. Ultrastructurally, the cells had characteristic osmiophilic lamellar bodies. By immunoperoxidase staining, the tumor cells were shown to have intracytoplasmic surfactant apoproteins. The postoperative course was uneventful, and there is no evidence of disease 8 years later.

Cystadenoma↗
PubMed1986

Multiple sclerosing hemangiomas of the lung.

A case of multiple "sclerosing hemangiomas" of the lung is reported. A 48-year-old housewife had several coin lesions in the right lower lung field, which were detected in a mass survey examination. There were no definite symptoms or signs except for hemoptysis. The resected right lower lobe of the lung contained innumerable lesions varying in size from microscopic to 3.7 cm in diameter, all of which were diagnosed as "sclerosing hemangioma." Although larger nodules revealed hemorrhagic, solid, papillary, and sclerotic features, smaller lesions, particularly minute ones, tended to be composed only of epithelial cells arranged in papillary patterns and so-called pale cells in solid areas, both of which are suggested to be main components of sclerosing hemangioma. Some lesions were associated with tumorlet or adenomatous hyperplasia (or adenoma) probably of the type 2 epithelial cell. It is not certain from this case study whether the lesions were multicentric in origin or intralobar metastases from one primary lesion. The patient's postoperative course was uneventful, and there is no evidence of recurrence 2 years after surgery.

Female↗
PubMed1986

A study on location of synthetic site which mainly synthesizes and delivers fifth component of complement system in vivo.

Tissue sites for synthesis of the fifth component of complement (C5) in vivo have been investigated by using allogeneic bone marrow chimeras and bone marrow chimeras which were transplanted in addition with hepatocytes. Our prior studies have demonstrated that bone marrow chimeras which had been prepared by transplanting marrow cells from C5-sufficient donor mice into irradiated C5-deficient recipients lacked detectable levels of C5 in the sera. However, when such potentially C5-deficient [C5(+)---C5(-)] chimeras were introduced into their spleens by means of injections of fully dispersed single cell suspensions of hepatocytes isolated from the C5-sufficient donor strain, they accepted the transplantation of hepatocytes for prolonged periods and developed a measurable amount of C5 in the sera. These results indicate that C5 protein in sera is not synthesized in significant amount by cells that are descendants of bone marrow cells but rather that this complement component is synthesized and delivered to the blood in vivo by somatic cells including liver cells that are not derivatives of the bone marrow.

Animals↗
PubMed1986

Mechanism of action of calcitonin gene-related peptide in stimulating pancreatic enzyme secretion.

In guinea pig pancreatic acini rat calcitonin gene-related peptide (CGRP) caused an eightfold increase in amylase release with various phosphodiesterase inhibitors present. Rat CGRP and rat [Tyro]CGRP caused half-maximal effect at 2 nM, and were threefold more potent than human CGRP. CGRP-stimulated amylase release was not inhibited by VIP-(10-28) or secretin-(5-27). CGRP stimulated cAMP and was augmented by phosphodiesterase inhibitors with the order of sensitivity being Ro-20-1724 greater than isobutylmethylxanthine greater than theophylline. CGRP did not increase 45Ca outflux or effect of 125I-VIP binding. CGRP specifically inhibited 125I-CGRP binding. The dose-response curves were broad and each peptide accelerated dissociation of bound 125I-CGRP. Computer analysis demonstrated two classes of CGRP-binding sites. Occupation of a high-affinity class (Kd 20 nM) correlated with stimulation of enzyme secretion and cAMP, and occupation of the low-affinity class (Kd 1 microM) correlated with accelerated dissociation. These studies demonstrate that CGRP interacts with specific pancreatic receptors, CGRP-stimulated cAMP is in a different compartment from that stimulated by other secretagogues, and CGRP differs from other agents that increase cAMP and amylase release in the relationship among receptor occupation, cAMP generation, and enzyme secretion.

1-Methyl-3-isobutylxanthine↗
PubMed1986

Five-year disease-free survival of a lung cancer patient treated only by photodynamic therapy.

A 59-year-old woman had suffered cough and sputum production for several months. Chest x-ray film findings were negative, but sputum cytology yielded a diagnosis of squamous cell carcinoma. This stage Ia lung cancer in the right upper lobe bronchus was deemed inoperable due to poor cardiopulmonary function. She was treated by photodynamic therapy in February 1981, involving intravenous injection of hematoporphyrin derivative and fiberoptic endoscopically delivered argon dye laser light. She responded well to the treatment and the lesion disappeared within a week. At present, she is apparently disease-free more than five years after treatment. This is the first known report of five-year disease-free survival following treatment of a malignant lesion by PDT only.

Carcinoma, Squamous Cell↗
PubMed1986

Heat and chemical stability of blood group-specific immunoglobulins in the state of immunecomplex.

Immune agglutinin or precipitin loses its reactivity with the corresponding antigen by heating or some chemicals. A. Se group saliva or M group blood stain was sensitized with human IgM anti-A or rabbit IgG anti-M serum, respectively. After being washed with saline, the stains were heated or treated with formalin or 2-mercaptoethanol (2-ME) of various concentrations. The immunoreactivity of the antibodies in the state of immunecomplex was examined by the mixed agglutination or elution test, indicating IgM and IgG antibodies in the state of immunecomplex were proof against heating up to 150 degrees C for 10 min and against formalin and 2-ME of high concentrations. It is considered that IgM and IgG acquire a new property of heat and chemical stability by formation of immunecomplex although they are substantially heat and chemical labile.

Animals↗