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R Hayashi

Publications and source records attributed to R Hayashi.

At least 73 records · Page 4Linked to original sources
PubMed2000

[A case of moyamoya disease presenting with geographic mislocation, person misidentification and fantastic confabulation].

A 52-year-old woman presented with geographical mislocation (misidentification for place), person misidentification and fantastic confabulation as a result of cerebral infarction. Head MRI demonstrated a focal lesion in the right frontal lobe. Cerebral angiogram demonstrated occlusion in the circle of Willis with moyamoya vessels. The neuropsychological examination revealed memory impairment and frontal lobe dysfunction. The patient's misidentification for place and person as well as confabulation lasted for 1.5 months since admission, then gradually disappeared. We speculate that there existed a common mechanism for these three symptoms; i.e., misidentification and confabulation were based upon the impaired interpretation of the small events and partial objects in the surrounding circumstances, which might interfere with the appropriate integration and judgments of the outside information in general. The impaired monitoring and frontal dysfunction caused by the right frontal lesion appeared to be responsible for causing her deficits.

Brain↗
PubMed1999

Significant differences in the frequency of transcriptional units, types and numbers of repetitive elements, GC content, and the number of CpG islands between a 1010-kb G-band genomic segment on chromosome 9q31.3 and a 1200-kb R-band genomic segment on chromosome 3p21.3.

We determined the nucleotide sequence of the entire 1,010,525-bp insert contained in CEPH YAC clone 867e8. This human genomic segment was derived from chromosome 9q31.3 and corresponds to a G-band region. We compared this segment, in terms of structure, with a previously characterized 1,201,033-bp sequence in CEPH YAC936c1 that had come from a portion of human chromosome 3p21.3 corresponding to an R-band region. The two segments were significantly different with respect to the frequency of transcriptional units, the types and numbers of repetitive elements present, their GC content, and the number of CpG islands. Alu elements, GC content, and CpG islands all showed positive correlations with the abundance of exons, but the distribution of LINE1s did not. These observations might reflect an influence of the first three of these features on the functions or expression of genes in the respective regions. In addition to a novel gene (F36) lying at the centromeric end of the 9q segment, we found a cluster of placenta-specific genes within a small section (about 400 kb) on the telomeric side of YAC867e8. This cluster consisted of four apparently unrelated ESTs and two genes, pregnancy-associated plasma protein-A (PAPP-A) and a novel gene (tentatively named EST-YD1). Our characterization of the two chromosomal regions provided evidence that genes are not evenly distributed throughout the human genome, and that gene richness is correlated with the GC content and with the frequency of either Alu elements or CpG islands.

Alu Elements↗
PubMed1999

A sequence-ready contig map of the top arm of Arabidopsis thaliana chromosome 3.

A fine physical map of the top arm of Arabidopsis thaliana chromosome 3 has been constructed by ordering P1, TAC and BAC clones using the sequences of a variety of DNA markers and end-sequences of clones. The marker sequences used in this study were derived from 58 DNA markers, 93 YAC end-sequences, and 807 end-sequences of P1, TAC and BAC clones. The entire top arm of chromosome 3, except for the centromeric and telomeric regions, was covered by a single contig 13.3 Mb long. This fine physical map will facilitate gene isolation by map-based cloning experiments as well as genome sequencing of the top arm of chromosome 3. The map and end-sequence information are available on the web site KAOS (Kazusa Arabidopsis data Opening Site) at [http://www.kazusa.or.jp/arabi/].

Arabidopsis↗
PubMed1999

Characterization of a 1200-kb genomic segment of chromosome 3p22-p21.3.

We previously determined the nucleotide sequence and characterized the 685-kb proximal half of CEPH YAC936c1, which corresponds to a portion of human chromosome 3p21.3. In the study reported here, we characterized the remaining 515-kb of this YAC clone corresponding to the telomeric half of its human insert. The newly sequenced region contained a total of ten genes including six reported previously: phospholipase C delta 1 (PLCD1), human activin receptor type IIB (hActR-IIB), organic cation transporter-like 1 (OCTL1), organic cation transporter-like 2 (OCTL2), oxidative stress response 1 (OSR1), and human xylulokinase-like protein (XYLB). The remaining four genes present in the telomeric region included two known genes, MyD88 and ACAA, and two novel genes. One (designated ENGL) of the novel sequences was found to encode an amino-acid sequence homologous to the family of DNA/RNA endonucleases, especially endonuclease G. The other gene F56 revealed no significant homology to any known genes. These results disclosed complete physical and transcriptional maps of the 1200-kb region of 3p present in YAC 936c1.

Amino Acid Sequence↗
PubMed1999

Role of the endogenous prostaglandin E2 in human lung fibroblast interleukin-11 production.

Interleukin-11 (IL-11) is known to be a member of the interleukin-6 (IL-6)-type cytokine family. IL-11 is likely to be a major determinant of immune regulation in acute and chronic inflammatory lung diseases, although it is not directly linked with specific disease processes. It has already been shown that although unstimulated human lung fibroblasts did not produce significant amounts of IL-11, the addition of interleukin-1 alpha (IL-1 alpha) and/or transforming growth factor-beta (TGF-beta) stimulated fibroblasts dose-dependently to produce IL-11. Northern blot analysis showed that these stimulators also upregulated IL-11 mRNA expression. As it has been previously reported that IL-1 and TGF-beta stimulate prostaglandin E2 (PGE2) release from lung fibroblasts, we investigate here the role of endogenous PGE2 and the direct effects of the two inhibitors of prostaglandin synthesis, indomethacin and dexamethasone, on IL-11 production by human lung fibroblasts. The addition of indomethacin, a cyclo-oxygenase inhibitor, resulted in significant suppression of IL-11 production and mRNA expression in lung fibroblasts. There was no detectable effect of PGE2 alone on IL-11 levels; however, the suppression of IL-11 production by indomethacin was almost completely reversed by addition of PGE2. In contrast, suppression of IL-11 production by indomenthacin was not reversed by addition of thromboxane B2 and carbocyclic thromboxane A2. In addition, dexamethasone completely suppressed IL-11 production and downregulated IL-11 mRNA. These results suggest that endogenous PGE2 acts as an autocrine stimulus for IL-11 production by human lung fibroblasts activated by IL-1 alpha and TGF-beta.

Anti-Inflammatory Agents↗
PubMed1999

Contribution of the carbohydrate moiety to conformational stability of the carboxypeptidase Y high pressure study.

The process of pressure-induced denaturation of carboxypeptidase Y and the role of the carbohydrate moiety in its response to pressure and low temperature were investigated by measuring in situ the catalytic activity and, the intrinsic and 8-anilino-1-naphthalene sulfonic acid binding fluorescences. Pressure-induced denaturation of carboxypeptidase Y is a process involving at least three transitions. Low pressures (below 150 MPa) induced slight conformational changes characterized by a slight decrease in the center of the spectral mass of intrinsic fluorescence, whereas no changes in 8-anilino-1-naphthalene sulfonic acid binding fluorescence were observed and 80% of the catalytic activity remained. Higher pressure (150-500 MPa) induced further conformational changes, characterized by a large decrease in the center of the spectral mass of intrinsic fluorescence, a large increase in the 8-anilino-1-naphthalene sulfonic acid binding fluorescence and the loss of all catalytic activity. Thus, this intermediate exhibited characteristics of molten globule-like state. A further increase, in pressure (above 550 MPa) induced transition from this first molten globule-like state to a second molten globule-like state. This two-stage denaturation process can be explained by assuming the existence of two independent structural domains in the carboxypeptidase molecule. A similar three-transition process was found for unglycosylated carboxypeptidase Y, but, the first two transitions clearly occurred at lower pressures than those for glycosylated carboxypeptidase Y. These findings indicate that the carbohydrate moiety protects carboxypeptidase Y against pressure-induced denaturation. The origin of the protective effects is discussed based on the known crystallographic structure of CPY.

Carboxypeptidases↗
PubMed1999

Cardiovascular function before and after iron therapy by echocardiography in patients with iron deficiency anemia.

BACKGROUND: The aim of the study was to estimate the left ventricular contractility using the ratio of left ventricular end-systolic wall stress to left ventricular end-systolic volume index in patients with iron deficiency anemia, for which there are no previous reports. METHODS: Cardiovascular functions were evaluated using echocardiography and pulsed Doppler echocardiography in 30 children aged 3-14 years (hemoglobin 4.9-8.5 g/dL), before, during and after iron therapy. We also studied 38 healthy children as a control group. RESULTS: The left ventricular preload was significantly higher and the left ventricular afterload was lower in the patients with anemia before iron therapy. The ratio of left ventricular end-systolic wall stress to left ventricular volume, an index of systolic function that is independent of preload and afterload, was significantly lower in the patients with anemia before iron therapy (before iron therapy 2.13 +/- 0.44, after therapy 3.52 +/- 0.76, healthy controls 3.42 +/- 0.70). Left ventricular early diastolic filling was significantly higher in the patients with anemia before iron therapy. The cardiac index was also significantly higher before therapy because of the increases in preload, heart rate and early diastolic filling, as well as the decrease of afterload. There were no significant differences in the indices of cardiovascular function between anemic patients after iron therapy compared with control subjects. CONCLUSIONS: The ratio of left ventricular end-systolic wall stress to the left ventricular volume index and the cardiac index suggested that a hemoglobin concentration < or = 6 g/dL was associated with left ventricular dysfunction and circulatory congestion.

Adolescent↗
PubMed1999

Free adipofascial flap for scalp reconstruction: case report.

The authors describe a case in which a large defect of the scalp was present after tumor excision. It was covered with a free adipofascial flap and a split-thickness skin graft, with satisfactory results. Numerous similar cases of scalp defects reconstructed with other free flaps have been described. But since donor-site morbidity is minimized with free adipofascial flaps, they should be used more often for reconstruction of scalp defects.

Adipose Tissue↗
PubMed1999

Increased urinary phosphate excretion in pseudohypoparathyroidism type II with long-term treatment with phosphodiesterase inhibitor.

A 58-year-old woman was diagnosed to have pseudohypoparathyroidism (PHP) type II because of the absence of an increase of urinary phosphate secretion, despite a marked increase in urinary cAMP excretion on the Ellsworth-Howard test. We treated the patient with a cyclic-nucleotide phosphodiesterase inhibitor, theophylline, resulting in increased urinary phosphate and cAMP excretions. Dibutyl cAMP administration induced the increase in the urinary phosphate excretion. In this case, the unresponsiveness of the urinary phosphate secretion to cAMP was recovered by a high dose of cAMP or long-term administration of a phosphodiesterase inhibitor. These data imply that cAMP responsiveness to renal tubular phosphate reabsorption should be more strictly elucidated in the patient with PHP type II.

Bucladesine↗
PubMed1999

Prf, a novel Ets family protein that binds to the PU.1 binding motif, is specifically expressed in restricted stages of B cell development.

During the development of lymphocytes, expression of the Ig genes is strictly regulated in a tissue-specific manner and in a time-ordered fashion. We have previously shown that the PU.1 binding motif in the Igkappa 3' enhancer (kappaE3') and a novel Ets family protein other than PU.1 may be possibly involved in the control of V(kappa)-J(kappa) joining. In the attempt to isolate the novel Ets family protein, we have screened cDNA libraries with the yeast one-hybrid method and identified a new PU.1-related factor, Prf. This novel Ets family protein is shown to interact with the PU.1 binding sequences in various promoters and enhancers, including kappaE3'. It was found that expression of the prf gene is predominant in the B-lineage cells, with the exception of immature B cells. Since Prf does not exhibit functions of transcriptional activity, this novel protein may act as an antagonist against other Ets family proteins, e.g. PU.1 and Spi-B. Possible roles of Prf with respect to the B cell differentiation are discussed.

Amino Acid Sequence↗
PubMed1999

A large maxillofacial prosthesis for total mandibular defect: a case report.

We successfully fabricated a large maxillofacial prosthesis for replacement of a total mandibular defect resulting from surgical failure to reconstruct the mandible. Although a number of reports have described procedures for fabricating midfacial prostheses, there is little information on prostheses to compensate for total loss of the mandible. A 54-year-old woman was referred to the Dentistry and Oral Surgery Division of the National Cancer Center Hospital with total loss of the mandible and the surrounding facial soft tissue. The facial prosthesis we used to treat this patient is unique in that it is adequately retained without the use of extraoral implants and conventional adhesives. This prosthesis is retained by the bilateral auricles and the remaining upper front teeth. We present details of the design of this large silicone maxillofacial prosthesis, with which we successfully rehabilitated the patient.

Female↗
PubMed1999

Carboxypeptidase Y: structural basis for protein sorting and catalytic triad.

A yeast vacuolar protease, carboxypeptidase Y (CPY), is known to be involved in the C-terminal processing of peptides and proteins; however, its real function remains unclear. The CPY biosynthetic pathway has been used as a model system for protein sorting in eukaryotes. CPY is synthesized as a prepro-form that travels through the ER and Golgi to its final destination in vacuoles. In the course of studies on the transport mechanism of CPY, various post-translational events have been identified, e.g. carbohydrate modification and cleavage of the pre-segments. In addition, sorting signals and various sorting vehicles, similar to those found in higher eukaryotic cells, have been found. The catalytic triad in the active site of CPY makes this enzyme a serine protease. A unique feature distinguishing CPY from other serine proteases is its wide pH optimum, in particular its high activity at acidic pH. Several structural properties which might contribute to this unique feature exist such as a conserved free cysteine residue in the S1 substrate binding pocket, a recognition site for a C-terminal carboxyl group, and a disulfide zipper motif. The structural bases in CPY functions are discussed in this article.

Binding Sites↗
PubMed1999

Comparison of innervated and noninnervated free flaps in oral reconstruction.

Thirteen patients who had undergone ablative surgery for advanced squamous cell carcinoma in which more than half of the tongue had been resected underwent reconstruction in which the cutaneous nerve of a free flap was anastomosed to the stump of the transected lingual nerve. Eight of the patients underwent reconstruction with an innervated anterolateral thigh flap and five patients underwent reconstruction with an innervated rectus abdominis musculocutaneous flap. Sensory recovery of the flap at least 6 months postoperatively was compared in these 13 patients and in 16 additional patients who received noninnervated versions of the same flaps for the same defect. The degree of sensory recovery of innervated thigh flaps was significantly greater than that of noninnervated ones in all modalities and that of innervated rectus abdominis flaps was also greater than that of noninnervated flaps, except for hot and cold perception. These results indicate that sensory regrowth occurs in most areas through the surgically created pathways. However, results of Semmes-Weinstein testing showed that recovery did not reach the level of protective sensation in either type of innervated flap. Although these findings must be followed by additional objective and functional tests and the need for sensory reeducation should be considered, this simple operative procedure can improve postoperative intraoral function and should be attempted whenever possible after ablative surgery.

Abdominal Muscles↗
PubMed1999

Reactive oxygen intermediates stimulate interleukin-6 production in human bronchial epithelial cells.

Reactive oxygen intermediates (ROIs) play an important role in the initiation and progression of lung diseases. In this study, we investigated whether ROIs were involved in the induction of interleukin (IL)-6 in human bronchial epithelial cells. We exposed normal human bronchial epithelial cells as well as a human bronchial epithelial cell line, HS-24, to ROIs. We measured the amount of IL-6 in the culture supernatants using ELISA and the IL-6 mRNA levels using RT-PCR. Superoxide anions (O-2), but not hydrogen peroxide (H2O2), increased IL-6 production. To examine whether it is a cell type-specific mechanism of airway epithelial cells, the experiments were also performed in human lung fibroblasts, WI-38-40. In WI-38-40 cells, neither O-2 nor H2O2 increased IL-6 production. In contrast, tumor necrosis factor (TNF)-alpha (200 U/ml) induced IL-6 at the protein and mRNA levels in both airway epithelial cells and lung fibroblasts. This cytokine-induced IL-6 production was significantly suppressed by several antioxidants, including dimethyl sulfoxide (DMSO), in airway epithelial cells. In WI-38-40 cells, DMSO was not able to suppress IL-6 production induced by TNF-alpha. Pretreatment with DMSO recovered the TNF-alpha-induced depletion of intracellular reduced glutathione in HS-24 cells. These findings indicate that oxidant stress specifically induces IL-6 production in human bronchial epithelial cells and that in these cells ROIs may be involved in IL-6 production after stimulation with cytokines such as TNF-alpha. Presumably, ROIs participate in the local immune response in lung diseases via IL-6 release from bronchial epithelial cells.

Antioxidants↗
PubMed1999

Ultrastructural changes of erythrocyte membrane skeletons in chorea-acanthocytosis and McLeod syndrome revealed by the quick-freezing and deep-etching method.

The shapes of acanthocytic erythrocytes have been thought to be related to changes of the organization of the membrane components. In this study, acanthocytes from a patient with chorea-acanthocytosis and a patient with McLeod syndrome were examined. These acanthocytes had a greater tendency to form spikes than normal erythrocytes in an incubation culture system, indicating their weakness against membrane tension. The membrane skeletons of erythrocytes from both patients were examined by our erythrocyte-splitting method followed by the quick-freezing and deep-etching method. The ultrastructural organization of the membrane skeletons was heterogeneous even in individual erythrocytes, indicating regional changes in the compactness of their meshworks. In the process of erythrocyte splitting, some erythrocyte membranes became reversed and protruded into the cytoplasmic side. In these regions, there were fewer filamentous structures. The focal membrane skeletal changes, which are probably one of the factors that induce the phenotype of an acanthocytic erythrocyte, were demonstrated for the first time by this method.

Acanthocytes↗
PubMed1999

Optically active antifungal azoles. VIII. Synthesis and antifungal activity of 1-[(1R,2R)-2-(2,4-difluoro- and 2-fluorophenyl)-2-hydroxy-1-methyl-3-(1H-1,2,4-triazol-1-yl)propyl]- 3-(4-substituted phenyl)-2(1H,3H)-imidazolones and 2-imidazolidinones.

New optically active antifungal azoles, 1-[(1R,2R)-2-(2,4-difluoro- and 2-fluorophenyl)-2-hydroxy-1-methyl-3-(1H-1,2,4-triazol-1-yl)propyl ]-3-(4- substituted phenyl)-2(1H,3H)-imidazolones (1,2) and 2-imidazolidinones (3,4), were prepared in a stereocontrolled manner from (1S)-1-[(2R)-2-(2,4- difluoro- and 2-fluorophenyl)-2-oxiranyl]ethanols (15, 16). Compounds 1-4 showed potent antifungal activity against Candida albicans in vitro and in vivo, as well as a broad antifungal spectrum for various fungi in vitro. Furthermore, the imidazolidinones, 3b--e and 4d, e, were found to exert extremely strong growth-inhibitory activity against Aspergillus fumigatus.

Animals↗
PubMed1999

Role of carbohydrate moiety in carboxypeptidase Y: structural study of mutant enzyme lacking carbohydrate moiety.

To study the roles of the carbohydrate moiety in the function of carboxypeptidase Y, asparagine residues at 13, 87, 168, and 368, the four-consensus N-linked glycosylation sites, were altered to alanine with site-directed mutagenesis. The mutant enzyme of 51 kDa completely lost the carbohydrate moiety which was present in the 61-kDa wild-type enzyme. Structural studies of the mutant enzyme showed that it maintained the native-like structure; hydrolytic activity, and substrate specificity of the mutant enzyme analogous to those of the wild-type enzyme. Susceptibility of the mutant enzyme toward proteolysis and pressure denaturation was reduced by 10-20%. It is concluded that the carbohydrate moiety functions to maintain the structural integrity of the enzyme under stressed.

Carbohydrates↗