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H Moriyama

Publications and source records attributed to H Moriyama.

At least 109 records · Page 6Linked to original sources
PubMed1998

Gene therapy for hepatic micrometastasis of murine colon carcinoma.

BACKGROUNDS/AIMS: Pit cells are located in the hepatic sinusoids and are organ-associated natural killer cells that contribute to immune surveillance in the liver. In the present study, the interleukin-2 gene was introduced into hepatocytes using an adenovirus vector to induce interleukin-2 production in an attempt to enhance the natural killer activity of pit cells, leading to inhibition of metastasis of colon carcinoma. METHODS: The recombinant adenovirus vector "Adex1CAmIL2" was constructed by inserting an expression unit which was composed of the CAG promotor (cytomegalovirus enhancer plus chicken beta-actin promotor), murine interleukin-2 cDNA, and a rabbit beta-globin polyadenylation signal. After administration of Adex1CAmIL2 to mice (4x10(7) pfu per animal), the expression of murine interleukin-2 in hepatocytes was examined by immunostaining and in situ hybridization, and the natural killer activity of hepatic mononuclear cells was measured. Inhibition of hepatic metastasis of colon carcinoma was examined after infusion of colon 38 tumor cells into the superior mesenteric vein. RESULTS: After administration of Adex1CAmIL2, interleukin-2 mRNA expression was demonstrated in hepatocytes until day 7, and the serum interleukin-2 level was increased. The natural killer activity of hepatic mononuclear cells was markedly enhanced for 7-10 days. Hepatic metastasis was inhibited by administration of Adex1CAmIL2 until day 7 after tumor cell inoculation. CONCLUSION: These results suggest that gene therapy using Adex1CAmIL2 could be potentially useful for inhibiting hepatic micrometastasis by enhancing the natural killer activity of pit cells.

Actins↗
PubMed1998

Expression of transforming growth factor-alpha (TGF-alpha) in cholesteatoma.

This study aims at elucidating the role of cytokines in the mechanism of proliferation of cholesteatoma epithelium by investigating the mode of expression of epidermal growth factors, such as TGF-alpha. The subjects of this study were patients who had undergone operation for middle ear cholesteatoma. Skins of the bone region of the external ear canal (normal skin) of the same patients were used as the negative control. The mode of expression of TGF-alpha was studied by immunohistochemistry and in situ hybridization. In the immunohistochemical study, there were no conspicuous differences observed between cholesteatoma tissues and normal skin. After in situ hybridization, expression of TGF-alpha mRNA was mainly observed in the epidermal basal cell layer in the normal skin, while in the cholesteatoma epidermis with severe inflammatory cell infiltration, expression of TGF-alpha mRNA was observed up to layers superior to the basal cell layer. The expression of TGF-alpha mRNA is greatly affected by subepithelial connective tissue, strongly suggesting involvement of paracrine regulation in proliferation of cholesteatoma epithelium.

Adolescent↗
PubMed1998

A study on epidermal proliferation ability in cholesteatoma.

With the objective of estimating proliferation ability of epidermis of middle ear cholesteatoma, the difference in proliferating cell nuclear antigen (PCNA) staining between the skin of the bone region of the external ear canal (control skin) and cholesteatoma epidermis and the effects on PCNA staining of subepidermal inflammatory cell infiltration of cholesteatoma were immunohistochemically studied using an antibody against PCNA. Transforming growth factor-alpha (TGF-alpha) is known to promote epidermal proliferation based on autocrine mechanism. But it is not clear that cholesteatoma epidermis is actually in the state of hyperproliferation under the effect of this growth factor. To estimate the effect of TGF-alpha on epidermal proliferation ability, the authors compared the location of PCNA and TGF-alpha in the same specimen. Unlike the control skin, not only epidermal basal cell layer and suprabasal cell layer, but also more superior layers were found to have high levels of PCNA staining in the epidermis of cholesteatoma. However, in the same cholesteatoma epidermal tissue, the PCNA staining was varied and the difference was ascribable to subepidermal cell inflammation. It appeared that the proliferation ability was high in regions where subepidermal inflammatory cell infiltration was severe. These differences in microenvironment are inferred to greatly affect proliferation ability of cholesteatoma epidermis.

Adult↗
PubMed1998

Relationship between middle ear pressure, mucosal lesion, and mastoid pneumatization.

OBJECTIVES: The inflammatory changes of pneumatic space mucosa are thought to affect the development of pneumatic space and the function of transmucosal gas exchange. So, it is assumed that the mucosal change is deeply involved in the onset and healing process of otitis media with effusion (OME). The objective of this study is to investigate whether the growth of the mastoid cells and the middle ear transmucosal gas exchange function in patients with OME are affected by the histopathologic changes in middle ear mucosa, and whether these two factors are changed by the treatment of OME. MATERIALS AND METHODS: From 65 children with OME, middle ear mucosal specimens were collected during indwelling of a tympanic tube, and their histopathologic changes were compared with cell growth area measured on radiographic films and with the change in the middle ear total pressure (METP). RESULTS: Suppression of the cell growth area was stronger and the METP stayed lower in cases with a higher degree of mucosal lesion. Significant expansion of pneumatic area was observed after 2 years of tube indwelling, and the peak METP showed a significant increase after 1.5 years. This increase in the METP was caused by diffusion/absorption of CO2 and O2 and indicated recovery of the transmucosal gas exchange function. CONCLUSIONS: The growth of the mastoid cells and the middle ear transmucosal gas exchange function are closely affected by the subepithelial histopathologic changes in middle ear mucosa, and these two factors recover by the treatment of OME.

Adolescent↗
PubMed1998

Infectivity and immunogenicity of SIVmac/HIV-1 chimeric viruses (SHIVs) with deletions in two or three genes (vpr, nef and vpx).

Two SHIVs with two or three genes deleted (SHIV-drn and SHIV-dxrn) were constructed. The inoculation of monkeys with SHIV-drn resulted in short-term viremia, but inoculation with SHIV-dxrn did not. At 68 weeks post-inoculation, the monkeys were reinoculated with a 100-fold higher dose of each SHIV, but none showed viremia. Killer cell activities against HIV-1 Env were detected in the SHIV-drn- and SHIV-dxrn-inoculated monkeys. Cross-reactive killer activity against HIV-1 Gag and SIVmac Gag was observed in one monkey. Antibodies were not detected in the SHIV-dxrn-inoculated monkeys, but the SHIV-drn-inoculated monkeys showed an anamnestic antibody reaction. These data indicate that SHIV-drn is infectious to and immuno-inducible in macaques but SHIV-dxrn is not.

AIDS Vaccines↗
PubMed1998

Expression of Fos in the rat forebrain following experimental tooth movement.

Orthodontic tooth movement is known to cause pain and discomfort to patients. Mechanically induced inflammatory responses in the periodontium are assumed to be related to the mechanism of pain sensation. An immediate-early gene, c-fos, that is expressed within some neurons following synaptic activation, is widely used as a marker for neuronal activity following noxious or innocuous stimulation. We have recently demonstrated that experimental tooth movement produced Fos induction in the ipsilateral trigeminal subnucleus caudalis and in the bilateral lateral parabrachial nucleus, which is known to be involved in the transmission of nociceptive information. As a further step, we investigated the distribution of Fos-like immunoreactive neurons in the upper brain regions. Twenty-four hours after the commencement of the experimental tooth movement, the Fos-like immunoreactive neurons appeared in the central nucleus of the amygdala (Ce), paraventricular nucleus of the hypothalamus (PVH), and paraventricular nucleus of the thalamus (PV) of the experimental rats. The numbers of the labeled neurons were significantly increased by 639% (P < 0.001) and 644% (P < 0.001) in the ipsilateral and contralateral sides of the Ce, respectively, by 292% (P < 0.001) and 307% (P < 0.001) in the ipsilateral and contralateral sides of the PVH, and by 264% (P < 0.0001) in the PV with respect to sham control rats. These results suggest that nociceptive information caused by experimental tooth movement might be transmitted and modulated in several regions of the forebrain.

Analysis of Variance↗
PubMed1998

[72 cases of the auditory ossicle malformations but with normal findings in the tympanic membrane].

We evaluated 66 patients (72 ears) with auditory ossicle malformations, but with normal findings in the tympanic membrane, who underwent ossicular reconstruction and stapes surgery at our department between 1984 and 1997. There were 27 men (30 ears) and 39 women (42 ears). Classification of pathologic condition based on surgical findings showed separation of the incus-stapes joint in 43%, fixation of the malleus or incus in 16%, fixation of the stapes footplate in 26%, in incidence of fixation of the auditory oosicles that is higher than that previously reported. In 33% of the patients, conductive hearing loss or mixed hearing loss similar to that observed on the affected side was also present on the contralateral side. Abnormalities in the arrangement of the facial nerves were noted in 4%, inner ear malformation in 1%, and congenital cholesteatoma in 3%. Auditory ossicle reconstruction was performed by the modified type III method in 57% and by the modified type IV method in 37% of the cases. During stapes surgery, 86% underwent small-fenestra stapedectomy. Improvement in hearing after the operation was observed in 90% of the cases and the improvement was relatively high compared with tympanoplasty for chronic otitis media.

Adolescent↗
PubMed1998

[The influence of sleep breathing disorder on growth hormone secretion in children with tonsil hypertrophy].

INTRODUCTION: Recently it has been revealed that Obstructive Sleep Apnea Syndrome has an influence on the endocrine system, especially to the secretion of growth hormone (GH). It was previously reported that secretion of GH has a circadian rhythm along with a correlation with slow wave sleep. Normally in a pediatric patient, after 90 min of sleep the brain wave shows patterns of deep sleep, and a matching peak in GH secretion is observed. We have studied the effect of GH secretion in sleep breathing disorder of pediatric patients by observing the pre- and post-operative difference in GH secretion in children with tonsillar hypertrophy who had tonsillectomies. MATERIAL AND METHODS: Ten pediatric patients who complained of sleep apnea or hypopnea, and were highly suspected of having sleep breathing disorders due to tonsil hypertrophy and underwent surgery were chosen. Pre and post-operative blood somatomedin C and urinary growth hormone levels were measured. In 6 of the 10 patients blood GH levels were measured after overnight collection of blood every 30 min through a catheter placed in the vein. METHOD OF ANALYSIS: Integral blood GH calculated from GH levels of the blood samples taken every 30 min was used to express the efficacy of GH secretion during sleep, and was compared with blood somatomedin C and urinary GH levels. Pre- and post-operative somatomedin C and urinary GH measurements were compared. RESULT: 1) In 6 of the 10 patients, there was a positive correlation with integral GH and urinary GH, and no correlation with integral GH or somatomedin C. 2) Post-operatively, 7 of the 10 patients had increased urinary GH levels, 1 showed no change and 2 had decreased levels. There was a significant increase in the mean urinary GH levels from 18.6 +/- 16.1 pg/ml pre-operatively to 35.8 +/- 19.6 pg/ml post-operatively (P < 0.05). 3) Eight of the 10 patients had a post-operative increase in somatomedin C levels, 1 showed no change and the other patient had a decreased level. There was a significant increase in mean somatomedin C levels from 175.9 +/- 124.8 ng/ml pre-operatively to 226.6 +/- 134.3 ng/ml post-operatively (P < 0.01). CASE: An 8-year-old-boy was diagnosed as having habitual tonsillitis and suspected sleep breathing disorder, and was admitted to our hospital for a tonsillectomy. Apnea and hypopnea were observed during sleep in the hospital. After receiving his parents' consent, GH secretion was evaluated before and after the tonsillectomy. Integrated GH measurements, somatomedin C and urinary GH increased significantly after the operation. CONCLUSION: In this study, the improvement of sleep breathing disorder by surgery was associated with a positive effect to the GH secretion. GH secretion is important for growth of a child. Wen the cause of sleep breathing disorder is evident in the upper airway system, active treatment and cure by surgery is advised. Measurement of urinary GH in the morning is useful and simple for evaluating the ability to secrete GH.

Biomarkers↗
PubMed1998

[Intraoperative coronary artery spasm treated by percutaneous cardiopulmonary support in a patient with left lung cancer].

A 53-year-old man with left lung cancer underwent left upper lobectomy and extended mediastinal lymphadenectomy. Shortly before the end of the operation, electrocardiogram showed elevation of ST wave and multiple ventricular premature contractures first, then ventricular fibrillations, and finally cardiac arrest. Coronary artery spasm was strongly suspected. The patient was resuscitated by cardiac massage and countershock immediately, however, such attacks repeated several times. As medication and cardiac pacing were not effective, percutaneous cardiopulmonary support (PCPS) was established. The hemodynamics was stabilized with PCPS. He was weaned off PCPS the next day. He was discharged and has had no attack so far. PCPS is an excellent modality for intraoperative coronary spasm which is uncontrollable by medicines and other methods.

Carcinoma, Squamous Cell↗
PubMed1997

Studies on selection blockers. 5. Design, synthesis, and biological profile of sialyl Lewis x mimetics based on modified serine-glutamic acid dipeptides.

We have rationally designed a sLe(x) mimetic based on molecular modeling, synthesized type II and type II' beta-turn dipeptides (3a,b), and evaluated their biological profiles both in vitro and in vivo. Against E-selectin-sLe(x) binding, the type II beta-turn dipeptide L-Ser-D-Glu 3a (IC50, 13 microM) and the type II' beta-turn dipeptide D-Ser-L-Glu 3b (IC50, 5.5 microM) were 20-100-fold more potent blockers than sLe(x) (1; IC50, 600 microM) and a 3'-sulfated Le(x) analog (2; IC50, 280 microM). On the other hand, other stereoisomers, such as L-Ser-L-Glu 3c and D-Ser-D-Glu 3d, were very weak blockers, with IC50 > 1000 microM for both 3c,d. Against the P- and L-selectins, despite much different stereochemistry of compounds 3a-d, the dipeptides 3a-d were all more potent blockers than either sLe(x) or compound 2. Interestingly, compound 3b provided significant in vivo efficacy against an immunoglobulin E-mediated skin reaction in a mouse model. These findings indicate that sLe(x) mimetics with type II and type II' beta-turn dipeptides could be useful in the design of an active selectin blocker in vitro and/or in vivo.

Animals↗
PubMed1997

c-fos expression in the trigeminal sensory complex and pontine parabrachial areas following experimental tooth movement.

Ortodontic tooth movement causes continuous pain. However, it does not appear immediately, usually appearing after the application of orthodontic force to the teeth. Mechanically induced inflammatory responses in the periodontal membrane are assumed to be related to the mechanism of the later pain sensation. In the present study, we investigated Fos-like immunoreactivity in the trigeminal sensory complex and pontine parabrachial areas 24 h after the commencement of experimental tooth movement. An orthodontic elastic module was unilaterally inserted between upper molars. Following experimental tooth movement, Fos-like immunoreactive neurons appeared ipsilaterally in the trigeminal subnucleus caudalis and bilaterally in the lateral parabrachial nucleus. These results indicate that experimental tooth movement evokes delayed and continuous nociception after application of orthodontic force to the teeth and that the nociceptive information would be conveyed to the ipsilateral trigeminal subnucleus caudalis and further processed, at least in part, to the lateral parabrachial nucleus.

Animals↗
PubMed1997

The crystal structure of zinc-containing ferredoxin from the thermoacidophilic archaeon Sulfolobus sp. strain 7.

The crystal structure of ferredoxin from the thermoacidophilic archaeon Sulfolobus sp. strain 7 was determined by multiple isomorphous replacement supplemented with anomalous scattering effects of iron atoms in the Fe-S clusters, and refined at 2.0 A resolution to a crystallographic R value of 0.173. The structural model contains a polypeptide chain of 103 amino acid residues, 2 [3Fe-4S] clusters, and 31 water molecules; in this model, the cluster corresponding to cluster II in bacterial dicluster ferredoxins loses the fourth iron atom although it may originally be a [4Fe-4S] cluster. The structure of the archaeal ferredoxin consists of two parts: the core fold part (residues 37-103) and the N-terminal extension part (residues 1-36). The "core fold" part has an overall main-chain folding common to bacterial dicluster ferredoxins, containing two clusters as the active center, two alpha-helices near the clusters, and two sheets of two-stranded antiparallel beta-sheet (the terminal and central beta-sheets). The "N-terminal extension" part is mainly formed by a one-turn alpha-helix and a three-stranded antiparallel beta-sheet. The beta-sheet in the N-terminal extension is hydrogen-bonded with the terminal beta-sheet in the core fold to form a larger beta-sheet. The distinct structural feature of this archaeal ferredoxin lies in the zinc-binding center where the zinc ion is tetrahedrally ligated by four amino acid residues (His 16, His 19, and His 34 from the N-terminal extension, and Asp 76 from the core fold). The zinc ion in the zinc-binding center is located at the interface between the core fold and the N-terminal extension, and connects the beta-sheet in the N-terminal extension and the central beta-sheet in the core fold through the zinc ligation. Thus, the zinc ion plays an important role in stabilizing the structure of the present archaeal ferredoxin by connecting the N-terminal extension and the core fold, which may be common to thermoacidophilic archaeal ferredoxins.

Amino Acid Sequence↗
PubMed1997

Macrophage differentiation and expression of macrophage colony-stimulating factor in murine milky spots and omentum after macrophage elimination.

To elucidate the differentiation mechanisms of macrophages in the murine omentum, we studied the repopulation of these cells and the expression of macrophage colony-stimulating factor (M-CSF) in the milky spots and omental tissues in mice depleted of macrophages following administration of liposome-encapsulated dichloromethylene diphosphonate (clodronate). The macrophages in the omentum were spindle or dendritic in shape, expressed several macrophage-specific antigens and Ia antigen, and phagocytized intraperitoneally injected carbon particles. In the milky spots, macrophages and macrophage precursors were detected, and the number of precursors increased after elimination of macrophages by intraperitoneal injection of liposome-encapsulated clodronate. Macrophage precursors in the milky spots proliferated, moved to the omentum, and transformed into dendritic-shaped macrophages. Expression of M-CSF mRNA extracted from the milky spots was markedly enhanced at 2 and 3 days after macrophage depletion. Localization of M-CSF protein and mRNA was observed in the stromal cells of the milky spots. In osteopetrosis (op/op) mutant mice that are defective in the production of functional M-CSF omental macrophages were absent. These results indicate that M-CSF locally produced in the milky spots plays an important role in providing a microenvironment for development and differentiation of omental macrophages.

Animals↗
PubMed1997

CD8 cytotoxic T-cell clone rapidly transfers autoimmune diabetes in very young NOD and MHC class I-compatible scid mice.

A CD8 T-cell clone (YNK1.3) generated from acutely diabetic NOD mouse islets, showed proliferation and cytotoxicity when challenged with NOD and BALB/c islet cells and NOD-derived insulinoma cells. When 1-2 x 10(7) YNK1.3 cells were administered to 7-10-day-old NOD mice, the cells transferred overt diabetes very rapidly in each of the 16 recipients within 4 days of cell transfer. However, of 14 recipients receiving YNK 1.3 cells above 14 days of age none became diabetic. Fluorescent dye-labelled YNK1.3 cells extensively accumulated in the islets by 36 h after transfer in 7-day-old NOD recipients, while no significant insulitis was seen in 21-day-old recipients. Over half of NOD-scid recipients (5/9) rapidly became diabetic within 5 days after transfer of 1-2 x 10(7) YNK1.3 cells at 7 days of age, whereas only one of 12 recipients over 14 days of age became diabetic. Furthermore, YNK1.3 cells also transferred diabetes to H-2Kd-matched very young BALB/c-scid and CB17-scid mice, but not to C57BL/6-scid mice. Thus, optimally activated islet-specific CD8 T-cell clones are able to rapidly transfer diabetes to NOD and MHC class I compatible scid mice when a large enough number is administered at 7 days of age. Administration of monoclonal antibodies against adhesion molecules involved in the trafficking of lymphocytes from the circulation into the inflammatory tissues, could not prevent the cellular infiltration of YNK1.3 cells into the islets in 7-day-old NOD recipients. The results indicate that islet cells in the mouse around 7 days of age are generally susceptible to cytotoxic CD8 T cells, suggesting, therefore, that CD8 T cells may play an important role in the initiation of autoimmune diabetes in NOD mice.

Adoptive Transfer↗
PubMed1997

The 2.8 A structure of hydroxylamine oxidoreductase from a nitrifying chemoautotrophic bacterium, Nitrosomonas europaea.

The 2.8 A crystal structure of hydroxylamine oxidoreductase of a nitrifying chemoautotrophic bacterium, Nitrosomonas europaea, is described. Twenty-four haems lie in the centre bottom of the trimeric molecule, localized in four clusters within each monomer. The haem clusters within the trimer are aligned to form a ring that has inlet and outlet sites. The inlet is occupied by a novel haem, P460, and there are two possible outlet sites per monomer formed by paired haems lying within a cavity or cleft on the protein surface. The structure suggests pathways by which electron transfer may occur through the precisely arranged haems and provides a framework for the interpretation of previous and future biochemical and genetic observations.

Amino Acid Sequence↗
PubMed1997

Isolation and characterization of matrix associated region DNA fragments in rice (Oryza sativa L.).

To investigate the interactions between chromosomal DNA and nuclear matrices in higher plants, matrix associated regions (MARs) of rice (Oryza sativa L.) DNAs were cloned. First, we prepared nuclear matrices from isolated nuclei by digesting them with EcoRI and then extracting with 2 M NaCl. About 6% of the total DNA remained in the nuclear matrices after this digestion and extraction. The residual DNA fragments in the nuclear matrices were cloned. Some of the cloned DNA fragments showed binding to certain nuclear proteins. One of the MAR fragments contained sequences related to known consensus motifs and a hairpin loop structure. A method is presented for isolation of matrix associated region (MAR) DNAs from plant cells.

Base Sequence↗
PubMed1997

A mutation at the interface between domains causes rearrangement of domains in 3-isopropylmalate dehydrogenase.

The structure of a thermostable Ala172Leu mutant, designated A172L, of 3-isopropylmalate dehydrogenase from Thermus thermophilus was determined. The crystal belongs to space group P2(1), with cell parameters a = 55.5 A, b = 88.1 A, c = 72.0 A and beta = 100.9 degrees. There is one dimer in each asymmetric unit. The final R factor is 17.8% with 69 water molecules at 2.35 A resolution. The mutation is located at the interface between domains and the C alpha trace of the mutant structure deviates from that of the native structure by as much as 1.7 A, while the structure of each domain barely changes. The mutant enzyme has a more closed conformation compared with the wild-type enzyme as a result of the replacement of Ala with Leu at residue 172. These structural variations were found independent of the crystal packing, because the structure of wild type was the same in crystals obtained in different precipitants. The hinge regions for the movement of domains are located around the active cleft of the enzyme, an observation that implies that the mobility of domains around the hinge is indispensable for the activity of the enzyme. The larger side chain at the mutated site contributed to the thermostability of the mutant protein by enhancing the local packing of side chains, and also by shifting the backbone of the opposing domain.

3-Isopropylmalate Dehydrogenase↗