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H Moriyama

Publications and source records attributed to H Moriyama.

At least 145 records · Page 8Linked to original sources
PubMed1996

[Patency of the ostium of the frontal sinus after endoscopic endonasal surgery for chronic sinusitis].

We examined the patency of the ostium of the frontal sinus after endoscopic endonasal surgery for chronic sinusitis. This study involved one hundred and seventy-two nasal sides of ninety cases who underwent surgery in this unit in the preceding three-year period by the designated three surgeons. All patients were followed up for more than one year after surgery. We obtained a high postoperative patent rate of 90.1%. However, communication between the frontal and ethmoidal sinus could not be confirmed in 9.9% of the cases due to the presence of polyp or adhesion in the middle meatus. Cases with preoperative severe lesion of the frontal sinus showed significantly lower rates of patent than cases with preoperative mild and/or no lesion. In cases where the opening of the ostium could not be sufficiently widened during surgery because the size around the ostium was already small, lower patent rates resulted. However, even in such cases, scraping or curetting of the surrounding bone should be avoided, because it may cause postoperative narrowing of the ostium due to new bone formation. Cases with unsatisfactory results caused by pathological changes in the middle meatus showed significantly lower patent rates than cases with satisfactory postoperative results. It is recommended that accurate cleaning of the ethmoid sinus and adequate postoperative treatment be considered important. Endoscopic endonasal opening of the ostium of the frontal sinus is shown to be a safe and reliable procedure, which can be performed with clear visualization.

Adolescent↗
PubMed1996

[Comparative study on the assay for IgE antibodies specific for Chamaecyparis obtusa pollen between AlaSTAT and CAP-RAST].

Titers of IgE antibody specific for the pollen of Chamaecyparis obtusa (C. obtusa) were determined by AlaSTAT and CAP-RAST in 221 patients with Japanese cedar pollinosis. IgE antibody to C. obtusa tested positive by CAP-RAST at a higher rate (80.5%) than by AlaSTAT (52.6%). The results obtained from the two assays were compared with those from intradermal skin test. CAP-RAST had a higher sensitivity than that of AlaSTAT. Because the two methods showed no differences in the determination of IgE antibody specific for Cryptomeria japonica, the above differences between AlaSTAT and CAP-RAST are surmised to be ascribable to the differences of C. obtusa antigen used in the both assays.

Adolescent↗
PubMed1996

Repopulation of murine Kupffer cells after intravenous administration of liposome-encapsulated dichloromethylene diphosphonate.

Kupffer cells were selectively eliminated in mice by the intravenous administration of liposome-entrapped dichloromethylene diphosphonate. At 5 days, small peroxidase-negative and acid-phosphatase-weakly-positive macrophages appeared, increased in number, and differentiated into peroxidase- and acid-phosphatase-positive Kupffer cells. Repopulating small macrophages actively proliferated, and the number of Kupffer cells returned to the normal level by day 14. The numbers of macrophage precursors in the liver as detected by the monoclonal antibodies ER-MP20 and ER-MP58 increased after liposome-entrapped dichloromethylene diphosphonate injection. ER-MP58-positive cells proliferated and differentiated into ER-MP20-positive cells and eventually into BM8-positive Kupffer cells in the liver. Bone-marrow-derived ER-MP58-positive cells were also detectable in the liver and differentiated into ER-MP20-positive cells, but they did not become BM8-positive macrophages. Macrophage colony-stimulating factor mRNA expression was enhanced in the liver 1 day after injection. The administration of macrophage colony-stimulating factor did not shorten the period of Kupffer cell depletion but increased the number and the proliferative capacity of repopulating Kupffer cells. These findings implied that repopulating Kupffer cells are derived from a macrophage precursor pool in the liver rather than from bone-marrow-derived monocytes. Local production of macrophage colony-stimulating factor in the liver plays a crucial role in the differentiation, maturation, and proliferation of Kupffer cells.

Animals↗
PubMed1995

Administration of monoclonal antibodies against vascular cell adhesion molecule-1/very late antigen-4 abrogates predisposing autoimmune diabetes in NOD mice.

The interaction of vascular cell adhesion molecule-1 and very late antigen-4 (alpha 4 beta 1-integrin) has been recently known to be profoundly involved in the trafficking of lymphocytes from the circulation into the inflammatory tissues. To elucidate the role of these molecules in the development of autoimmune diabetes, the expression of these adhesion molecules on inflamed islets and the effects of administration of monoclonal antibodies to these molecules on insulitis and overt diabetes were evaluated in nonobese diabetic (NOD) mice. Immunohistochemical study revealed the overexpression of vascular cell adhesion molecule-1 on vascular endothelium near or within inflamed islets and alpha 4-integrin on islet-infiltrating mononuclear cells. Either anti-vascular cell adhesion molecule-1 or anti-alpha 4-integrin monoclonal antibody prevented the transfer of diabetes in irradiated NOD mice which received spleen cells from acutely diabetic NOD mice. When both monoclonal antibodies were administrated to NOD mice during 2-30 weeks of age, neither lymphocytic infiltration to islets nor overt diabetes was observed. Furthermore, administration of these antibodies even from 10 weeks of age could inhibit the development of insulitis and diabetes, whereas administration during 2-5 weeks of age could not. Splenocytes obtained from these treated mice showed no significant change of cytokine production and preserved the ability to transfer diabetes into NOD scid/scid mice. This suggests that treatment with antibodies against these adhesion molecules can inhibit insulitis and diabetes without affecting the Th1/Th2 balance or effector T cells. The blockade of vascular cell adhesion molecule-1/very late antigen-4 interaction would be suitable for therapeutical treatment of the predisposing and latent type I (insulin-dependent) diabetic subjects.

Animals↗
PubMed1995

Double-stranded RNA in rice: a novel RNA replicon in plants.

The entire sequence of 13952 nucleotides of a plasmid-like, double-stranded RNA (dsRNA) from rice was assembled from more than 50 independent cDNA clones. The 5' non-coding region of the coding (sense) strand spans over 166 nucleotides, followed by one long open reading frame (ORF) of 13716 nucleotides that encodes a large putative polyprotein of 4572 amino acid residues, and by a 70-nucleotide 3' non-coding region. This ORF is apparently the longest reported to date in the plant kingdom. Amino acid sequence comparisons revealed that the large putative polyprotein includes an RNA helicase-like domain and an RNA-dependent RNA polymerase (replicase)-like domain. Comparisons of the amino acid sequences of these two domains and of the entire genetic organization of the rice dsRNA with those found in potyviruses and the CHV1-713 dsRNA of chestnut blight fungus suggest that the rice dsRNA is located evolutionarily between potyviruses and the CHV1-713 dsRNA. This plasmid-like dsRNA in rice seems to constitute a novel RNA replicon in plants.

Amino Acid Sequence↗
PubMed1995

The unusual structure of a novel RNA replicon in rice.

A linear, plasmid-like, double-stranded RNA (dsRNA) was isolated from rice, and its entire sequence of 13,952 nucleotides (nt) was determined. The dsRNA encodes a single, unusually long, open reading frame (13,716 nt, 4,572 amino acid residues), which includes an RNA helicase-like domain and an RNA-dependent RNA polymerase-like domain. A series of Northern hybridization and primer extension experiments revealed that the coding (sense) strand of the dsRNA contains a discontinuity (nick) at a position 1,211 nt (or 1,256 nt) from the 5' end. This discontinuity divides not only the coding strand of dsRNA molecule into a 1,211-nt fragment and a 12,741-nt fragment (or a 1,256-nt fragment and a 12,696-nt fragment) but also divides the long open reading frame into a 5' part of 1,045 nt (348 amino acid residues) and a 3' part of 12,671 nt (4,224 amino acid residues) or a 5' part of 1,090 nt (363 amino acid residues) and a 3' part of 12,626 nt (4,209 amino acid residues). It seems likely that almost all dsRNA molecules in rice plants contain such a discontinuity. This rice dsRNA appears to be a novel and unique RNA replicon.

Base Sequence↗
PubMed1995

The crystal structures of mutated 3-isopropylmalate dehydrogenase from Thermus thermophilus HB8 and their relationship to the thermostability of the enzyme.

The structures of two mutant forms (G240A and L246E/V249M) of 3-isopropylmalate dehydrogenase from Thermus thermophilus HB8 were studied by X-ray crystallography. In the case of G240A, the replacement of glycine by alanine at residue 240 was expected to decrease the thermostability as a result of abnormal contacts between the methyl group of alanine and the peptide chain. However, the normal van der Waals' contacts were achieved owing to a shift in a bundle of beta-strands that yielded a vacant space for the alanine residue. The extended hydrogen bonds within the beta-sheet are the major reason for the decreased thermostability of G240A. The mutations in L246E/V249M are located in an alpha-helix region which is involved in subunit-subunit contact via hydrophobic interaction. Loosening of the subunit-subunit contact owing to ionic repulsion was the major cause of the lower heat stability of L246E/V249M.

3-Isopropylmalate Dehydrogenase↗
PubMed1995

Crystallization and preliminary X-ray study of H2-proteinase from the venom of Trimeresurus flavoviridis.

H2-proteinase, a non-hemorrhagic metalloproteinase from the venom of Trimeresurus flavoviridis, has been crystallized by vapor diffusion from solutions containing ammonium sulfate. The crystals belong to the tetragonal space group, P41212 or P43212, with unit cell dimensions of a = b = 77.8 A and c = 82.3 A. The asymmetric unit contains one protein molecule. Diffraction data for a native crystal were collected up to 2.0 A resolution.

Animals↗
PubMed1995

Crystallization and preliminary X-ray studies of isocitrate dehydrogenase from Thermus thermophilus HB8.

Isocitrate dehydrogenase from the thermophilic bacterium, Thermus thermophilus HB8, was crystallized by the vapor diffusion hanging drop method with polyethylene glycol 6000 as the precipitant. Pillar-like crystals of about 0.6 x 0.6 x 0.3 mm3 were obtained. Analysis of a series of oscillation photographs indicated that the orthorhombic crystals belonged to the I222 or I2(1)2(1)2(1) space group with unit cell dimensions of a = 100.1 A, b = 150.4 A, and c = 87.4 A. Intensity data were collected up to 2.5 A resolution.

Crystallization↗
PubMed1995

Ligand-induced changes in the conformation of 3-isopropylmalate dehydrogenase from Thermus thermophilus.

The structures of 3-isopropylmalate dehydrogenase (IPMDH) from Thermus thermophilus in complexes with its substrate, cofactor, and a cofactor analog were investigated by X-ray diffraction in a crystalline state and by small-angle X-ray scattering (SAXS) in solution. The structures at 2.8 A resolution of the complexes with the substrate, 3-isopropylmalate (IPM), and with an analog of NAD, ADP-ribose, were both very close to the structure of the free enzyme, which adopts an open conformation. However, the binding of a ligand induced a small conformational change near the binding site. This result contrasts with results for NADP(+)-bound and isocitrate-bound isocitrate dehydrogenase (ICDH) from Escherichia coli, which adopts a closed conformation. The SAXS analysis in solution clearly showed that IPMDH without a ligand adopts two distinct intermediate conformations, between the open and closed states, upon binding of NADH and IPM respectively, and adopts a fully closed conformation when in a ternary complex with NADH and IPM together.

3-Isopropylmalate Dehydrogenase↗
PubMed1995

The crystal structure of thermostable mutants of chimeric 3-isopropylmalate dehydrogenase, 2T2M6T.

A chimeric 3-isopropylmalate dehydrogenase (IPMDH), 2T2M6T, was produced by replacing the amino acid sequences of the Thermus thermophilus enzyme with those of the Bacillus subtilis enzyme from residues 75 to 113. Decreased thermostability of the chimeric enzyme was recovered by either evolutionary engineering (I93L) or site-directed mutagenesis (S82R). The 3-D structures of the mutants have been determined by X-ray diffraction at 2.1 A resolution. Although S82R was refined routinely, I93L required the preliminary rigid-body refinement of each domain. The R-factors were reduced to 0.18 for both mutants. Removal of the unfavorable torsion angle at isoleucine 93 may have made I93L more thermostable than 2T2M6T. In the case of S82R, the replaced arginine residue contributed to the extra hydrogen bond with water molecules. The large replaced residue decreased the entropy of the solvent, which may have caused the improvement in enzyme thermostability. Denaturation by heating may be interpreted from these structural results.

3-Isopropylmalate Dehydrogenase↗
PubMed1995

Coronary dilating effects of intracoronary nicorandil. Comparison with isosorbide dinitrate.

Although nicorandil, N-(2-hydroxyethyl) nicotinamide dinitrate, is a nitrate ester, its cardiovascular action differs from that of nitrate compounds in several aspects. In this quantitative angiographic study, the acute coronary dilating effect of intracoronary nicorandil (0.25, 0.50, 1.0 mg) was compared with that of isosorbide dinitrate (ISDN; 1.0 mg) in 46 patients with or without ischemic heart disease (IHD). Dose-dependent right coronary dilating action was observed by intracoronary administration of nicorandil without any adverse effects. The same degree of right coronary dilation was achieved by the intracoronary application of equivalent doses of ISDN. We conclude that intracoronary administration of nicorandil is beneficial for the supportive treatment of IHD during coronary artery investigation and intervention without the risk of severe systemic hypotension.

Angina Pectoris↗
PubMed1995

Expression of intercellular adhesion molecule 1 on pancreatic beta-cells accelerates beta-cell destruction by cytotoxic T-cells in murine autoimmune diabetes.

Intercellular adhesion molecule 1 (ICAM-1) plays an important role in the pathogenesis of insulin-dependent diabetes mellitus (IDDM) by being involved in the extravasation of lymphocytes from the circulation into the inflamed pancreas. However, the mechanism of beta-cell destruction by which expression of ICAM-1 on beta-cells may facilitate adhesion of effector cells still remains to be elucidated. Several lines of evidence suggest that this adhesion molecule is involved in the destruction of pancreatic beta-cells by killer lymphocytes in the NOD mouse, which shows an autoimmune diabetic syndrome similar to that of human IDDM. Immunohistochemical study under light microscopy demonstrated that all of the mononuclear cells infiltrating the islets strongly expressed ICAM-1 and leukocyte function-associated antigen 1 (LFA-1), a counterreceptor of ICAM-1, whereas ICAM-1 expression on islet cells was not apparent. However, immunohistochemical staining under electron microscopy revealed that islet beta-cells adjacent to infiltrating lymphocytes were clearly stained by an anti-ICAM-1 monoclonal antibody (mAb). Flow cytometric analysis showed that the ICAM-1 expression on NOD islet cells and NOD-derived insulinoma cells (MIN6N8a) was inducible by interferon (IFN)-gamma or tumor necrosis factor-alpha. These cytokines had an additive effect on the ICAM-1 induction. Susceptibility of MIN6N8a cells to lysis by a NOD islet-derived CD8+ cytotoxic T-cell clone was greatly enhanced by IFN-gamma pretreatment, and this enhancement was abolished by anti-ICAM-1 and anti-LFA-1 mAbs. When both mAbs were administered into NOD mice with spontaneous or adoptively transferred diabetes, the development of diabetes was significantly prevented.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Morphometric analysis of neurons in ganglia: geniculate, submandibular, cervical spinal and superior cervical.

The geniculate ganglia (GG), the submandibular ganglion (SG), the cervical spinal ganglion (CSG) and the superior cervical ganglion (SCG) are clinically important. But details of these ganglia have not been included in textbook descriptions. We conducted research to bring precise figures to light. We prepared serial sections of these ganglia in five Japanese adults after precise dissections to count the numbers, measure the perimeters and the areas, and calculate the circularity ratios (CRs) of the ganglion cells. The numbers of neurons were in the following order: SCG > CSG > SG > GG, and the average neuronal areas in the following order: CSG > GG > SG > SCG. Average neuronal CRs were around 0.90 in all ganglia. In other words, the morphometric evaluation showed that neurons in such ganglia are practically circular in shape. Our morphometry thus reveals that the neurons in these ganglia are sensory neurons in the broad definition of the word from a quantitative point of view.

Adult↗
PubMed1995

[Eighteen cases of tortuosity of the internal carotid--usefulness of MR-angiography in diagnosis].

There have been few reports on tortuosity of the internal carotid exhibiting pulsation or swelling in the pharyngeal wall. Because this disease carries the risk of causing massive hemorrhage at the time of incision of a peritonsillar abscess, surgical treatment of the adenoids, or tonsillectomy, otolaryngologists should be aware of the existence of this disorder as a risk factor. We encountered tortuosity of the internal carotid in the pharynx in 18 cases over an approximately two year period. Females (15 cases) outnumbered males (3 cases), and the mean age was 68 years at the time of diagnosis. There was no right-to-left difference in terms of the incidence of the disease. The complication of hypertension was noted in 10 cases. MR-Angiography (MRA) was performed in 13 cases, and very clear images were obtained; this technique was useful for diagnosing this disorder. For the most part, contrast angiography has been employed for the diagnosis of this disorder, but various complications, including deaths, have been reported. As the incidence of tortuosity of the internal carotid is high in the elderly, it is thought that any complication which may occur has the potential to become serious. Non-invasive diagnostic techniques are thus recommended. MRA is absolutely non-invasive, and we therefore believe that this technique should be the modality of first choice for diagnosing tortuosity of the internal carotid.

Aged↗
PubMed1995

[Improvement of olfactory disturbance by endoscopic endonasal surgery for chronic sinusitis].

Olfactory disturbance is the one of the most important symptoms of chronic sinusitis. In the present study, we followed up the postoperative clinical course of olfactory disturbance in patients who underwent surgery for chronic sinusitis. Ninety patients with severe olfactory disturbance or anosmia who underwent endoscopic endonasal surgery for chronic sinusitis with severe olfactory disturbance or anosmia in the preceding three-year period were enrolled in this study. We obtained a high postoperative improvement rate of 78.8%. We compared and examined our cases' postoperative clinical course concerning their olfactory disturbance and various factors in other patients before and after surgery, and obtained the following results: a) Young patients, 30 years old or under at the time of surgery, showed significantly higher rates of improvement than patients who were 50 years old or more at the time of surgery. b) Even though revision surgery was performed, the improvement rates were almost the same as after the initial surgery. c) Although the Alinamin intravenous olfaction test is regarded as an olfaction threshold test, we have seen quite a few cases in which improvement was achieved despite the absence of a preoperative response to the Alinamin intravenous olfaction test. d) There was no clear correlation between the presence of preoperative lesions of the ethmoid sinus and the olfactory cleft and the improvement rates. e) The cases with unsatisfactory results concerning the paranasal sinuses and nasal cavity--those accompanied by postoperative adhesions of the olfactory cleft, recurrence of polyps, etc.,--showed significantly lower improvement rates than cases with satisfactory postoperative results. During surgery in patients with severe olfactory disturbance, we conclude that it is particularly important to adequately clean the lesions of the olfactory cleft and the anterior and posterior ethmoid sinus endoscopically. This ensures leaving clear the olfactory cleft.

Adult↗