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T Ichimura

Publications and source records attributed to T Ichimura.

At least 55 records · Page 3Linked to original sources
PubMed1997

Correlation between shrinkage of uterine leiomyoma treated with buserelin acetate and histopathologic findings of biopsy specimen before treatment.

OBJECTIVE: To analyze histopathologic features related to myoma volume reduction after treatment with a GnRH agonist, buserelin acetate, in needle biopsy specimens obtained before treatment. DESIGN: Prospective clinical study. SETTING: University teaching hospital. PATIENT(S): Twenty women with normal menstrual cycles and symptomatic uterine myomas. INTERVENTION(S): Buserelin acetate was administered intranasally (900 micrograms/d) for at least 16 weeks; transcervical needle biopsy of the uterine myoma was done before this treatment. MAIN OUTCOME MEASURE(S): The relation between histopathologic features (degree of cellularity, hyaline change, and collagen content) and the percent decrease in the volume of the largest myoma at 16 weeks measured by magnetic resonance imaging. RESULT(S): The correlation between the degree of hyaline change and the percent decrease in the myoma volume was significant, as was that with the proportion of collagenous tissue in the specimens. CONCLUSION(S): We predicted myoma volume reduction after treatment with a GnRH agonist by histologic analysis of the uterine leiomyoma before treatment.

Administration, Intranasal↗
PubMed1997

Long lasting smooth muscle relaxation by a novel PACAP analogue in guinea-pig and primate airways in vitro.

1. We compared the relaxant effect of pituitary adenylate cyclase activating peptide (PACAP) 1-27 with that of a newly developed PACAP 1-27 analogue, [Arg15,20,21Leu17]-PACAP-Gly-Lys-Arg-NH2, in the guinea-pig trachea and primate bronchi in vitro (n = 4-5). 2. In the guinea-pig trachea precontracted by a submaximally effective carbachol concentration (0.1 microM), cumulative administration of PACAP 1-27 and the beta 2-adrenoceptor agonist salbutamol (3 nM-3 microM) caused significant and concentration-dependent smooth muscle relaxation, with salbutamol being approximately one log-step more potent in this model. However, in primate bronchi precontracted by carbachol (0.1 microM), cumulative administration of PACAP 1-27 and salbutamol caused concentration-dependent smooth muscle relaxation with very similar potencies and maximum relaxant effects. 3. In the guinea-pig trachea, non-cumulative administration of the PACAP 1-27 analogue and the original PACAP 1-27 (0.3-3 microM) caused concentration-dependent relaxation with a very similar maximum relaxant effect and potency. However, the onset and offset of action was markedly slower for the PACAP 1-27 analogue than for the original PACAP 1-27 (< 90% versus < 10% of peak relaxation remaining 6 h after administration). Separate experiments confirmed that the PACAP 1-27 analogue also caused significant relaxation with slower onset and offset of action than did the original PACAP 1-27 in primate bronchi. 4. Peptidase inhibition by captopril (10 microM) and phosphoramidon (1 microM) significantly increased the maximum relaxant effect and duration of action of PACAP 1-27 but not of the PACAP 1-27 analogue, during the 3 h of observation in the guinea-pig trachea. 5. We conclude that [Arg15,20,21Leu17]-PACAP-Gly-Lys-Arg-NH2 produces significant, concentration-dependent and sustained airway smooth muscle relaxation in vitro. The sustained relaxant effect is due, at least in part, to the PACAP 1-27 analogue being less susceptible to cleavage by peptidases than the original peptide PACAP 1-27.

Albuterol↗
PubMed1997

cDNA cloning of nuclear localization signal binding protein NBP60, a rat homologue of lamin B receptor, and identification of binding sites of human lamin B receptor for nuclear localization signals and chromatin.

We previously purified and characterized a nuclear localization signal (NLS) binding protein, NBP60, in rat liver nuclear envelopes. In this study, we cloned and sequenced the cDNA of rat NBP60, and predicted an amino acid sequence comprising 620 amino acids. The sequence revealed that NBP60 is a rat homologue of lamin B receptor (LBR), and is 79 and 63% identical in amino acids to human and chicken LBR, respectively. Using three fusion proteins containing different parts of the amino-terminal domain of human LBR, it was shown that the stretch comprising amino acids 1 to 89, which contains a Ser-Arg rich region (RS region), binds to nucleoplasmin and that the binding was inhibited by a common NLS-peptide. These results suggested that the amino-terminal domain of LBR contains an NLS-binding site. Furthermore, it was shown that the stretch comprising amino acids 1 to 53, which does not contain the RS region or the predicted DNA-binding site, binds to Xenopus laevis sperm chromatin.

Amino Acid Sequence↗
PubMed1997

Characterization of the binding of nuclear envelope precursor vesicles and chromatin, and purification of the vesicles.

The binding of nuclear envelope precursor vesicles and chromatin was characterized by using an in vitro system constituted from a Xenopus egg extract and demembranated Xenopus sperm chromatin. The results of binding studies in the presence of salts, urea, and a chelator showed that the binding involves an ionic interaction. Chemical modification studies suggested that a protein(s) in the vesicles, which is responsible for the binding with chromatin, has essential lysine, histidine, and methionine residues. The vesicle protein could not be extracted from vesicles with 1 M KCl, 2 M urea, or 0.1 M Na2CO3, suggesting that it is an intrinsic membrane protein. The protein was denatured with 8 M urea and 0.1 M Na2CO3, and could be renatured by incubation at 23 degrees C, suggesting that the native conformation of the protein is important for the binding. Affinity purification of nuclear envelope precursor vesicles was achieved by binding to chromatin and dissociation with 0.24 M NaCl. The vesicle fraction thus obtained exhibited the ability to form nuclear envelope on incubation with chromatin in Xenopus egg cytosol without any other membrane fraction. These results suggested that there is a nuclear envelope precursor vesicle population containing both a chromatin targeting protein and vesicle fusion machinery.

Animals↗
PubMed1997

High levels of circulating interleukin-4 and interleukin-10 in Kawasaki disease.

For analysis of the cytokine network in Kawasaki disease (KD), we measured over time the plasma levels of interferon (IFN)-gamma, interleukin (IL)-4 and IL-10 in patients with KD. Fifteen patients with KD were studied. Eight healthy children were selected as control subjects. Circulating IFN-gamma levels were measured by immunoradiometric assay, and IL-4 and IL-10 levels were measured by enzyme-linked immunosorbent assay. The results were as follows: (1) The plasma levels of IFN-gamma in KD patients in the acute phase were significantly higher than the levels of patients in the convalescent phase (p < 0.05) and those of the control children (p < 0.05). (2) The plasma levels of IL-4 in the KD patients in the acute phase were significantly higher than the levels of the patients in the convalescent phase (p = 0.001) and those of the control children (p = 0.001). (3) The plasma levels of IL-10 in the KD patients in the acute phase were significantly higher than the levels of the patients in the convalescent phase (p < 0.03) and those of the control children (p < 0.005). (4) The investigation of the relationship between the IL-4 and IFN-gamma levels during the acute phase of KD demonstrated a significant reciprocal relationship (p < 0.05). (5) There was no significant relationship between the IL-4 and IL-10 levels during the acute phase. However, plasma IL-10 levels were low in the patients with high levels of plasma IL-4, and the patients with high levels of IL-10 revealed low levels of plasma IL-4. The above results suggested that a variety of patterns of cytokine production was present in the acute phase of this disease, and that the key cytokine, which might regulate the cytokine network, was IL-4.

Case-Control Studies↗
PubMed1997

Direct measurement of endosomal pH in living cells of the rat yolk sac epithelium by laser confocal microscopy.

Endocytosis of dual-fluorescent dextran by epithelial cells was observed in the perfused rat yolk sac using a confocal laser scanning microscope. Endosomal pH was quantified from confocal images using a dual-fluorescence ratiometry technique. Changes in endosomal pH were followed over time up to 32 min with and without Brefeldin A treatment. After 4 min of endocytosis without Brefeldin A, endosomes had a pH of 6.1 +/- 0.3. After 16 min and 32 min, their pH levels varied widely from 4.0 to 6.6. When Brefeldin A (10 microM) was added to the perfusion medium, endosomal pH remained fairly stable in the range of 6.0 to 6.2 from 4 min to 32 min. The corresponding endosomal structures were examined by electron microscopy after endocytic labeling with horseradish peroxidase. After 4 min, small endocytic vesicles and large endosomal vacuoles with tubular extensions were labeled. After 16 min and 32 min, multivesicular bodies and dense lysosomal structures were progressively labeled, but their labeling was almost undetectable after Brefeldin A treatment. These results suggested that the pH within the sorting compartment of early endosomes is 6.1 +/- 0.3. This is the first quantitative measurement of pH within sorting endosomes in intact cells of the living yolk sac epithelium.

Animals↗
PubMed1996

Immunological characterization of antibodies against synthetic peptides of glutamic acid decarboxylase.

We characterized antibodies against synthetic N-terminal peptides (glutamic acid decarboxylase; GAD65N and GAD67N) and a C-terminal peptide (GAD67C) of human GAD isoforms. On Western blots, the GAD65N antibody specifically stained the 65 kDa isoform and the GAD67N antibody the 67 kDa one in various mammalian brain tissues, whereas the GAD67C antibody stained both. The immunotrapped GAD enzyme activity increased in a dose-dependent manner with increasing concentration of the N-terminal peptide antibodies, but the activity was completely inhibited by the C-terminal peptide antibody. By an enzyme-linked immunosorbent assay using rat brain GAD purified on a GAD67C antibody-affinity column, we detected GAD antibodies in 40% (24/60) of the patients with long-standing insulin-dependent diabetes mellitus (IDDM). These antipeptide antibodies are a useful tool not only for identifying the GAD isoforms, but also for purifying GAD.

Animals↗
PubMed1996

Subcellular distribution and phosphorylation of the nuclear localization signal binding protein, NBP60.

We previously purified a nuclear localization signal binding protein, NBP60, from rat liver (1993, J. Biochem. 113, 308-313). In this study, the subcellular localization of NBP60 was examined using anti-NBP60. Most NBP60 was found to be localized in the nuclear envelope fraction of rat liver obtained on cell fractionation followed by immunoblotting. Staining of the nuclei of cultured cells by the antibody was observed on immunofluorescence microscopy. NBP60 was widely detected in rat nuclear fractions prepared from other tissues and also in nuclei of cultured cells derived from other species. It was shown by immunoelectron microscopy that most NBP60 is present in the nuclear envelope and at least some of that is present on nuclear pore complexes. Although NBP60 was localized in the nuclear envelope in interphase cells, it diffused into the cytoplasm in the mitotic phase. The purified NBP60 was highly phosphorylated by a cdc2 mitotic kinase, whereas nuclear pore proteins p144, p62, p60, and p54 were not phosphorylated by the kinase directly. NBP60 was also phosphorylated by protein kinase A, calmodulin-dependent protein kinase II, and casein kinase II. The phosphorylation of NBP60 by cdc2 kinase and/or the other kinases may be related to the change in the protein's location during the mitotic phase.

Animals↗
PubMed1996

Characterization of p92, karyopherin beta, co-purified with N-acetylglucosamine-bearing nucleoporins from rat liver nuclear envelopes.

A 92k protein (p92) was purified from the wheat germ agglutinin-Sepharose (WGA-Sepharose) bound fraction of a rat liver nuclear envelope salt-extract by DEAE-5PW and hydroxyapatite HPLCs. Partial amino acid sequence analysis of p92 revealed that it is karyopherin beta, which was found recently in the cytosolic fraction. It was shown using anti-p92 antiserum that the protein is present in the nuclear envelope and cytosolic fractions, in almost the same amounts, but not in other subcellular fractions of rat liver. p92 bound to N-acetylglucosamine bearing nucleoporins (GNPs) on WGA-Sepharose, but not directly to WGA. The amount of p92 found in the rat liver nuclear envelope fraction corresponded to about 10% of the nuclear pore complex in mass, and to as much as 140 mol of p92 per mol of nuclear pore complex. Hydrodynamic analysis of the purified p92 suggested that the molecule is present as a monomer and that it is a rod-shaped molecule. The interaction of p92 and GNPs seemed to be hydrophobic and ionic. Based on these results, the participation of nuclear envelope p92 in protein nuclear transport is discussed.

Acetylglucosamine↗
PubMed1996

Glomerulonephritis with predominant paramesangial IgG deposition.

The new clinicopathological entity, immunoglobin G (IgG)-associated mesangial proliferative glomerulonephritis (GN), has been reported recently, but serial renal biopsies were not performed in the cases reported. The findings of three serial renal biopsies in a pediatric case with IgG-associated GN and paramesangial deposits are reported. Microscopic hematuria was found incidentally at the age of 8 years and the hematuria often worsened transiently during periods of upper respiratory infections. The patient was treated mainly with dipyridamole. The third biopsy showed that both paramesangial hemispherical deposits and predominant mesangial IgG deposits had increased, while mesangial cell proliferation had markedly decreased. These serial biopsy findings suggest that IgG-associated GN with microscopic hematuria and slight proteinuria may be characterized by a relatively benign histological and clinical course, as described in recent reports.

Child↗
PubMed1996

Coffin-Siris syndrome: a case of an extremely low birthweight infant with severe kyphoscoliosis.

A case of Coffin-Siris syndrome in a male of extremely low birthweight with severe kyphoscoliosis is reported. His birthweight was 965 g, the lowest reported in the world for an infant with this syndrome. Coffin-Siris syndrome is characterized by nail hypoplasia of the fingers and toes, eyebrow hypertrichosis, prominent lips and prenatal or postnatal growth retardation. He was the only case who was mechanically ventilated from birth because of birth asphyxia. He died at 12 days of age because of sepsis, a poor immune system as in other extremely low birthweight infants, and because he easily suffered from upper respiratory infection as a result of Coffin-Siris syndrome. Kyphoscoliosis is suggested as one of the important features in low birthweight cases of Coffin-Siris syndrome in previous reports and in the present case.

Abnormalities, Multiple↗
PubMed1996

Chronic respiratory failure after acquired cytomegalovirus infection in a very low birthweight infant.

The case of a female infant who developed chronic respiratory failure after an acquired cytomegalovirus (CMV) infection is presented here. She was a very low birthweight (VLBW) infant and was free from oxygen supplement until 2 months after birth. Interstitial pneumonia occurred at 2 months of age, and her respiratory condition gradually deteriorated. A chest roentgenogram at 4 months revealed hyperinflation and reticular shadow, similar to that of severe chronic lung disease (CLD) in preterm infants. She was mechanically ventilated because of progressive respiratory deterioration, and oxygen dependency continued for 5 months after extubation. There are several previous reports of CMV pneumonia in term neonates or infants. However, there appears to be no published report on the pulmonary sequelae of CMV pneumonia in VLBW infants. The present case seems to indicate that acquired CMV pneumonia in VLBW infants causes chronic respiratory failure even when mechanical ventilation is not administered, and this respiratory failure is very similar to CLD in clinical symptoms and chest roentgenogram.

Chronic Disease↗
PubMed1996

Induction of FGF-7 after kidney damage: a possible paracrine mechanism for tubule repair.

A member of the fibroblast growth factor (FGF) family, keratinocyte growth factor (FGF-7 has unique specificity for epithelial cells. We investigated the role of FGF-7 in repair of proximal tubular damage caused by S-(1,1,2,2-tetrafluoroethyl)-L-cysteine (TFEC). In situ hybridization localized FGF-7 to interstitial cells in the medulla and outer stripe of the outer medulla. Interstitial FGF-7 expression increased throughout the kidney 1 day after TFEC treatment. FGFR2 IIIb mRNA was high in the papilla and medulla and also increased after TFEC administration. By in situ hybridization, FGFR2 IIIb was localized to the tubular epithelium, particularly in collecting ducts. Proliferation of collecting duct epithelial cells increased in adult kidney after damage to the proximal tubule. FGFR2 IIIb, but not FGF-7, mRNA was also expressed by rat proximal tubule epithelial (RPTE) cells in vitro, and FGF-7 increased DNA synthesis in RPTE. Thus FGFR2 IIIb and FGF-7 expression is segregated between epithelial and interstitial cells forming a paracrine growth factor loop. These results raise the possibility that a novel paracrine growth loop is activated by chemical damage and regulates epithelial cell growth during tubular repair.

Aging↗
PubMed1996

A brief review of epidemiological studies on ischemic heart disease in Japan.

The age-adjusted death rate from ischemic heart disease in Japan is the lowest among developed countries and the rates have decreased since 1970. The incidences of myocardial infarction in selected populations ranged between 0.12 and 2.56 per 1,000 for middle-aged males, and between 0.00 and 1.52 per 1,000 for females. The incidences of sudden death within 24 hours were from 0.00 to 1.58 per 1,000 for males and from 0.00 to 0.76 per/1,000 for females. The incidences in Japanese populations appeared to be far below those in Western populations. In the Cox proportional hazard regression model, hypertension and smoking were selected as independent risk factors for myocardial infarction in an agricultural district. It was noteworthy that the level of serum cholesterol was not associated with development of myocardial infarction in rural areas. No positive relation between dietary fat and serum cholesterol was observed in school children, suggesting that growth, sexual maturation and others might be confounding variables between them. The levels of serum cholesterol for females were more affected by menopause than those of blood pressures and body mass index. Although some polymorphisms in selected candidate genes appeared to be associated with some serum lipids and apolipoproteins, the effect of individual RFLP on the inter-individual variations in serum traits was relatively subtle in comparison with that of lifestyle factors.

Female↗
PubMed1996

Three-dimensional structure of myeloid bodies in the retinal pigment epithelium of the frog, Rana pipiens.

The three-dimensional structures of myeloid bodies (MBs) in the retinal pigment epithelium (RPE) of the frog (Rana pipiens) were studied by transmission and scanning electron microscopy. MBs were observed to be an assemblies of numerous membranous lamellae that were formed by a flattened saccule of the paired membranes in the RPE. On thin-section, they appeared as lenticular, crescentic, circular and spherical forms and were associated with adjacent smooth endoplasmic reticulum (SER) and nuclear membranes. The lenticular MBs were observed to be in connection with the crescentic, circular and spherical forms. Under scanning electron microscopy, the lenticular and crescentic MBs showed a pile of disc-liked lamellae, while the circular and spherical MBs displayed an onion-liked appearance. It was noted that some tubular SER remained in the center of the circular MBs, while the lamellae were compactly arranged and filled the central region in the spherical MBs. All crescentic and spherical MBs were continuous with the lenticular and crescentic MBs. These results suggest that the lenticular MBs may be a precursor form of another variety of MBs which may be transformed into the crescentic, circular and spherical forms by the curving and fusion of the lamellar membranes at the MB's free ends.

Animals↗