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Y Fujii

Publications and source records attributed to Y Fujii.

At least 361 records · Page 20Linked to original sources
PubMed1998

PU.1 as an essential activator for the expression of gp91(phox) gene in human peripheral neutrophils, monocytes, and B lymphocytes.

We have reported a deficiency of a 91-kDa glycoprotein component of the phagocyte NADPH oxidase (gp91(phox)) in neutrophils, monocytes, and B lymphocytes of a patient with X chromosome-linked chronic granulomatous disease. Sequence analysis of his gp91(phox) gene revealed a single-base mutation (C --> T) at position -53. Electrophoresis mobility-shift assays showed that both PU.1 and hematopoietic-associated factor 1 (HAF-1) bound to the inverted PU.1 consensus sequence centered at position -53 of the gp91(phox) promoter, and the mutation at position -53 strongly inhibited the binding of both factors. It was also indicated that a mutation at position -50 strongly inhibited PU.1 binding but hardly inhibited HAF-1 binding, and a mutation at position -56 had an opposite binding specificity for these factors. In transient expression assay using HEL cells, which express PU.1 and HAF-1, the mutations at positions -53 and -50 significantly reduced the gp91(phox) promoter activity; however, the mutation at position -56 did not affect the promoter activity. In transient cotransfection study, PU.1 dramatically activated the gp91(phox) promoter in Jurkat T cells, which originally contained HAF-1 but not PU.1. In addition, the single-base mutation (C --> T) at position -52 that was identified in a patient with chronic granulomatous disease inhibited the binding of PU.1 to the promoter. We therefore conclude that PU.1 is an essential activator for the expression of gp91(phox) gene in human neutrophils, monocytes, and B lymphocytes.

B-Lymphocytes↗
PubMed1998

Three-dimensional ultrastructure of apoptotic nuclei in rat prostatic epithelial cells revealed by a quick-freezing and deep-etching method.

BACKGROUND: To clarify intranuclear apoptotic changes, we have investigated chromatin organization in apoptotic nuclei of castrated rat prostatic cells by a quick-freezing and deep-etching (QF-DE) method. METHODS: The ventral prostates taken from intact and castrated adult male rats were investigated by light microscopy, in situ end-labeling (ISEL) technique, conventional electron microscopy, and the QF-DE method. RESULTS: In control nuclei, the chromatin fibers were uniformly distributed and formed a network structure. In apoptotic nuclei, destruction of such chromatin networks was detected, which was clearly seen by the QF-DE method. Although it first appeared spotty in the apoptotic nucleus, definite destruction of the intranuclear network occurred in the nuclear center at later stages, and broken fibrous structures were condensed along the nuclear margin. The ISEL technique was applied to the QF-DE method. Localization of damaged DNA fragments could three-dimensionally be detected on replica membranes. CONCLUSIONS: Intranuclear chromatin organization in apoptotic cell death of rat prostates was observed by the QF-DE method. We could examine early-stage apoptotic nuclei at an electron microscopic level, which would not be clarified by other conventional methods.

Animals↗
PubMed1998

A compact UHV X-ray diffractometer for studying surfaces and interfaces.

A compact ultra-high-vacuum (UHV) X-ray diffractometer for surface glancing X-ray scattering has been constructed. All the equipment, including a rotating-anode source of 18 kW and a UHV specimen chamber, is arranged on one optical table of dimensions 70 x 90 cm. The specimen chamber is 14 cm in diameter and 20 cm high and can be evacuated up to 3 x 10(-8) Pa. It is equipped with two Be windows of thicknesses 0.2 and 0.4 mm. Specimen orientation in the vacuum is controlled from the outside. The specimen can be heated up to 773 K. The chamber has two evaporation cells and can be used for in situ observations of growing crystal surfaces. Using this instrument, we observed a mechanically polished Ag surface and successfully made an in situ observation of the layer-by-layer growth of a PbSe(111) surface. The instrument will be useful for preliminary experiments using laboratory sources, prior to final measurements at synchrotron radiation facilities.

Journal Article↗
PubMed1998

Disruption of the RB pathway and cell-proliferative activity in non-small-cell lung cancers.

The pathway consisting of retinoblastoma protein (pRB), cyclin D1 and p16 (RB pathway) which is involved in the phosphorylation of pRB plays an important role in G1/S progression. The disruption of this RB pathway has been reported in several types of human neoplasm. An immunohistochemical study of 101 non-small-cell lung cancers (NSCLCs) showed loss of p16 is in 47 tumors (46.5%) and loss of pRB in 42 tumors (41.6%). In 79 of 101 NSCLCs (78.2%), the expression of p16 and pRB was complementary (p < 0.0001). Methylation of the cdkn2 gene was detected in 50% of p16-negative tumors and in 11% of p16-positive tumors. Aberrant expression of cyclin D1 was found in 45 tumors (44.5%). The cyclin-D1-positive tumors had significantly higher Ki-67 indices than the cyclin-D1-negative tumors irrespective of the tumor p16 or pRB expression. Thus, 91 (90%) of 101 NSCLCs showed disturbed expression of at least 1 of the 3 components of the RB pathway. Our results suggest that the disruption of the RB pathway plays an important role in tumorigenesis in NSCLCs and that increased cyclin-D1 expression leads to strong proliferative activity which may over-ride the suppressive effect of p16 and pRB.

Adenocarcinoma↗
PubMed1998

Urinary excretion of aquaporin-2 in term and preterm infants.

Aquaporin-2 (AQP-2) is a vasopressin-regulated water channel of the renal collecting duct and is excreted in human urine. We measured the urinary excretion of AQP-2 by radioimmunoassay in 14 term and 12 preterm infants aged 1 month. Excretion of AQP-2 was low compared with adults, and correlated significantly with urine osmolality in preterm infants. Our results demonstrate that AQP-2 water channels are expressed in the renal collecting duct of both term and preterm infants.

Aquaporin 2↗
PubMed1998

Activation of the precursor of human stromelysin 2 and its interactions with other matrix metalloproteinases.

Matrix metalloproteinases (MMP) are synthesized as inactive zymogens (proMMP) and subsequently activated by many factors to degrade the extracellular matrix (ECM). In the present study, we have examined the intermolecular activation mechanisms of proMMP by MMP-10 (stromelysin 2). ProMMP-10 was purified from the culture media of OSC-20 human oral squamous carcinoma cells stimulated with 12-O-tetradecanoylphorbol 13-acetate. The final products are partially activated (approximately 38% of the full activity) during the purification steps and contain proMMP-10 of Mr 56,000 with minor protein bands of Mr 47,000, 24,000 and 22,000. The zymogen is activated by 4-aminophenylmercuric acetate and processed to the active forms of Mr 47,000 and 24,000. The NH2-terminal sequence of the 47,000- and 24,000-Mr species is Phe82-Ser-Ser-Phe-Pro-Gly, which is identical to that of stromelysin 2. ProMMP-9 (progelatinase B) is activated by MMP-10 to its full activity and processed to the low-Mr species of Mr 81,000, 65,000, 57,000 and 55,000, the former two of which show proteolytic activity on a gelatin zymography. The NH2-terminal sequence analysis indicates that the 81,000-, 65,000- and 57,000-M, species have the identical sequence of Phe88-Gln-Thr-Phe-Glu-Gly, suggesting the cleavage of the Arg87-Phe88 peptide bond for activation and both NH2-terminal and COOH-terminal truncation in the 65,000- and 57,000-Mr forms. MMP-10 also activates proMMP-7 (promatrilysin) up to about 60% of the full activity and generates the same active species of Mr 19,000 as that obtained by activation with 4-aminophenylmercuric acetate. Incubation of proMMP-2 (progelatinase A) or proMMP-3 with MMP-10 does not result in activation of these proMMP. These results indicate that in addition to the previously reported activation of proMMP-1 (tissue procollagenase) and proMMP-8 (neutrophil procollagenase), MMP-10 can also activate proMMP-9 and proMMP-7, and suggest the possibility that MMP-10 may replace a role of MMP-3 in the ECM degradation in concert with other MMP under various pathological conditions.

Amino Acid Sequence↗
PubMed1998

A microsatellite instability analysis in neuroblastoma based on a high resolution fluorescent microsatellite analysis.

It has recently been reported that mismatch repair enzymes, which are one type of DNA repair enzymes, are the causative genes for a major group of hereditary non-polyposis colon cancers (HNPCC). Abnormalities in the mismatch repair system can be monitored by observing instability at the microsatellite loci (MSI) in cancer cells. MSI has been reported not only in tumors associated with hereditary non-polyposis colorectal cancer but also in sporadic forms of various tumors. No correlation between pediatric malignant tumors and the mismatch repair system has yet been reported. In the present study, we examined the frequency of MSI in 21 neuroblastomas, which are the most common solid tumors in childhood, using a high resolution fluorescent microsatellite analysis. MSI on five microsatellite loci was detected in none of the 21 samples. Other mechanisms independent of mismatch repair deficiency may thus play a role in both tumorigenesis and the development of neuroblastoma.

Child↗
PubMed1998

Immaturity of lymphocytes in the metastatic lesions of thymoma.

Thymoma is a thymic epithelial tumor which often contains a large number of immature T cells. Although the metastatic lesions are also associated with abundant lymphocytes, their characteristics have not been assessed in detail. In this study, the phenotype was analyzed and compared with those in their primary lesions. Nine metastatic thymomas were obtained from seven patients. In the metastatic lesions, CD1a+ cells and CD4(+)CD8(+) cells accounted for 77.7 +/- 10.6 and 52.3 +/- 15.8% of all the lymphocytes, respectively. In five primary lesions and their metastatic lesions, CD3(-)CD4(+)CD8(-) cells accounted for 23.9 +/- 16.9 and 45.2 +/- 15. 5% of the CD4(+)CD8(-) cells, respectively. CD69 was expressed on 70. 9 +/- 9.5 and 53.1 +/- 11.8% of the CD4(+)CD8(-) cells, respectively. These results indicate that the metastatic lesions of thymoma are associated with abundant immature T cells which are phenotypically less mature than those in their primary lesions.

Adult↗
PubMed1998

Crystallographic Characterization of the DNA-Binding Domain of Interferon Regulatory Factor-2 Complexed with DNA.

Interferon regulatory factors (IRFs) are transcription factors for interferon-related genes, which manifest both antiviral and tumor-suppressor activities and regulate cell growth in response to DNA damage. For the transcription initiation of the interferon-beta gene, IRFs form a macromolecular assembly bound to the promoter DNA, referred to as an enhancesome, together with several other transcription factors and DNA-binding proteins. The three-dimensional structure of IRF-DNA complex would provide insights into the structure and function of the enhancesome. In this study, we crystallized the DNA-binding domain of interferon regulatory factor-2 complexed with a DNA fragment. The crystals reproducibly grew by the vapor diffusion technique with 2-methyl-pentanediol from solutions containing small detergents, such as n-octyl-beta-d-glucoside. Cryocrystallographic experiments showed that crystals belong to space group P212121 with a = 90.66 Å, b = 101.01 Å, c = 171.58 Å and diffract up to 2.8 Å resolution. The absorption measurements of a solution in which the crystals were dissolved indicate that the DNA-binding domain binds to the DNA as a dimer. The calculated values of the solvent contents suggest that the protein-DNA complexes form a multimer in the crystal. These features may reflect the association of the complexes in the enhancesome. Copyright 1998 Academic Press.

Journal Article↗
PubMed1998

Need for TolC, an Escherichia coli outer membrane protein, in the secretion of heat-stable enterotoxin I across the outer membrane.

Escherichia coli heat-stable enterotoxin Ip (STIp) is a typical extracellular toxin consisting of 18 amino acid residues synthesized as a precursor of pre (amino acid residues 1 to 19), pro (amino acid residues 20 to 54), and mature (amino acid residues 55 to 72) regions. STIp synthesized in the cytoplasm must cross the inner and outer membranes to migrate into the extracellular environment. Previous studies showed that the precursor translocates across the inner membrane utilizing the general export pathway consisting of Sec proteins. However, it remains unclear how it crosses the outer membrane. In this study, we examined the effects of mutation of the tolC gene which encodes an E. coli outer membrane protein, TolC, on the release of STIp into the extracellular environment. The mutation reduced the amount of STIp released into culture supernatant and increased the amount of STIp accumulated in the periplasm. This indicates that TolC mediates the translocation of STIp across the outer membrane. The inability to transfer STIp in the periplasm into the culture supernatant was restored by introduction of the tolC gene into the mutant cells. In the mouse intestinal loop assay, living cells of the mutants did not show a positive response, but wild-type cells did. These results showed that TolC is involved in the translocation of STIp across the outer membrane.

Animals↗
PubMed1998

Calcium channel blockers attenuate cardiovascular responses to tracheal extubation in hypertensive patients.

PURPOSE: Hypertensive patients exhibit exaggerated cardiovascular responses to tracheal extubation. This study was undertaken to examine the inhibitory effects of calcium channel blockers, nicardipine and diltiazem, on haemodynamic changes after tracheal extubation. METHODS: Sixty hypertensive patients (ASA physical status II) undergoing elective orthopaedic (upper and lower extremity) surgery received, in a randomized, double-blind manner, 30 micrograms.kg-1 nicardipine, 0.2 mg.kg-1 diltiazem or saline (as a control) (n = 20 of each) i.v. before tracheal extubation. Changes in heart rate (HR), mean arterial pressure (MAP) and rate-pressure product (RPP) were measured before and after tracheal extubation. RESULTS: The HR, MAP and RPP increased after tracheal extubation in the control group (P < 0.05). The increases in these haemodynamic variables were attenuated with nicardipine or diltiazem. The inhibitory effects of diltiazem on these cardiovascular responses to tracheal extubation were greater than those of nicardipine (HR; 86 +/- 7 vs 101 +/- 10, RPP; 11,437 +/- 1,575 vs 14,675 +/- 2,874, mean +/- SD, P < 0.05). CONCLUSION: Compared with nicardipine, administration of diltiazem produced greater attenuating the circulatory responses to tracheal extubation in hypertensive patients.

Adult↗
PubMed1998

Diltiazem-lidocaine combination for the attenuation of cardiovascular responses to tracheal intubation in hypertensive patients.

PURPOSE: Hypertensive patients are prone to haemodynamic changes after laryngoscopy and tracheal intubation. This study was undertaken to compare the efficacy of a combination of diltiazem and lidocaine with that of each drug alone for suppressing the cardiovascular responses to tracheal intubation. METHODS: Sixty hypertensive patients (ASA II), defined as systolic blood pressure > 160 mmHg and/or diastolic blood pressure > 95 mmHg (World Health Organization), undergoing elective surgery received, in a randomized, double-blind manner, 0.3 mg.kg-1 diltiazem, 1.5 mg.kg-1 lidocaine, or 0.3 mg.kg-1 diltiazem plus 1.5 mg.kg-1 lidocaine i.v. (n = 20 of each) before the initiation of laryngoscopy. Anaesthesia was induced with 5 mg.kg-1 thiopentone i.v., and tracheal intubation was facilitated with 2 mg.kg-1 succinylcholine i.v. after precurarization with 0.02 mg.kg-1 vecuronium i.v. Changes in heart rate (HR), mean arterial pressure (MAP) and rate-pressure product (RPP) were measured before and at immediate, 1, 2, 3, 5 and 10 min after tracheal intubation. RESULTS: The inhibitory effects of diltiazem-lidocaine combination on cardiovascular responses to tracheal intubation was greater than those of diltiazem or lidocaine as a sole medicine (RPP; 10,602 +/- 1448 (combination) vs 11,787 +/- 1345 (diltiazem), 15,428 +/- 1756 (lidocaine), mean +/- SD, P < 0.05). CONCLUSION: Prophylactic therapy with diltiazem-lidocaine combination is more effective than diltiazem or lidocaine alone for attenuating the cardiovascular changes associated with tracheal intubation in hypertensive patients.

Aged↗
PubMed1998

Prophylactic antiemetic therapy with granisetron-droperidol combination in patients undergoing laparoscopic cholecystectomy.

PURPOSE: A relatively high incidence of postoperative nausea and vomiting (PONV) occurs in patients undergoing laparoscopic cholecystectomy. This study was undertaken to compare the efficacy of granisetron-droperidol combination with each drug alone for the prevention of PONV after laparoscopic cholecystectomy. METHODS: In a randomized, double-blind manner, 150 female inpatients received 3 mg granisetron (Group G), 1.25 mg droperidol (Group D) or 3 mg granisetron plus 1.25 mg droperidol (Group GD)(n = 50 for each) i.v. immediately before the induction of anaesthesia. The same standard general anaesthetic technique, which consisted of isoflurane and nitrous oxide in oxygen, was used. Nausea, vomiting and safety assessments were performed continuously during the first 24 hr after anaesthesia. RESULTS: Complete response, defined as no PONV and no administration of rescue antiemetic medication, was 86% in Group G, 64% in Group D and 98% in Group GD (P = 0.03 vs Group G, P = 0.001 vs Group D). No clinically adverse events were observed in any group. CONCLUSION: Granisetron-droperidol combination is more effective than each antiemetic alone in the prevention of PONV after laparoscopic cholecystectomy.

Adult↗
PubMed1998

Prevention of PONV with granisetron, droperidol or metoclopramide in patients with postoperative emesis.

PURPOSE: A high incidence of postoperative nausea and vomiting (PONV) has been noted in patients with a history of postoperative emesis. This study was undertaken to compare the efficacy of granisetron, droperidol and metoclopramide, in the prevention of PONV in such patients undergoing general anaesthesia for major gynaecological surgery. METHODS: In a randomised, double-blind study, 90 female patients received 2.5 mg granisetron, 1.25 mg droperidol or 10 mg metoclopramide (n = 30 of each) i.v. immediately before induction of anaesthesia. The same standard general anaesthetic technique, which consisted of isoflurane in nitrous oxide and oxygen, was used. Nausea, vomiting and safety assessments were performed continuously during the first 24 hr after anaesthesia. RESULTS: The incidence of PONV was 20% with granisetron, 57% with droperidol and 60% with metoclopramide (P < 0.05; overall Fisher's exact probability test). No clinically adverse events were observed in any group. CONCLUSION: Granisetron is more effective than droperidol or metoclopramide in preventing PONV in female patients with a history of postoperative emesis.

Adult↗
PubMed1998

Cardiovascular responses to tracheal extubation or LMA removal in children.

PURPOSE: This study was designed to investigate the cardiovascular effects related to tracheal extubation or laryngeal mask airway (LMA) removal in children. METHODS: Sixty children, ASA physical status 1, 4-10 yr of age, undergoing minor elective surgery (inguinal hernia and phimosis) were allocated randomly to have their surgery performed with endotracheal intubation (Group ET, n = 30) or LMA (Group LMA, n = 30) and were studied for cardiovascular responses related to extubation or LMA removal. Changes in heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured before and 1, 2, 3, 5, and 10 min after tracheal extubation or LMA removal when the patients were awake. RESULTS: The maximal changes in HR, SBP and DBP were less in Group LMA than in Group ET during the observation period (HR; 12 vs 26, SBP; 14 vs 28, DBP; 9 vs 13, median, P < 0.05). CONCLUSION: Laryngeal mask airway removal elicited less haemodynamic change than tracheal extubation in paediatric patients.

Blood Pressure↗
PubMed1998

Immunocytochemical study of lysosomal proteins with a new monoclonal antibody directed against epithelioid macrophages.

A monoclonal antibody, EPI-1, was produced against macrophages in epithelioid granulomas induced in rat foot pads by muramyl dipeptide. This EPI-1 antibody reacted to lysosome-like structures in epithelioid macrophages, peritoneal and pulmonary macrophages, and also in other tissues such as liver, testes, and kidneys. Western blot analysis of epithelioid granulomas, liver, testes, and kidneys revealed the same positive band of 62 kDa. Immunoelectron microscopic study of foot pad granulomas and hepatocytes demonstrated the EPI-1 antigen located in lysosomes and autophagic vesicles, preferentially along their membranes. These findings suggest that the EPI-1 antibody may recognize a novel antigen related to lysosomal membrane proteins in macrophages and other cells, which is useful for identifying lysosomes and their related structures.

Animals↗
PubMed1998

Poorly differentiated desmin-negative and vimentin-positive leiomyosarcoma of the stomach examined by the immunohistochemical and quick-freezing and deep-etching methods.

A poorly differentiated leiomyosarcoma of the stomach in a 41-year-old woman is reported. The diagnosis was confirmed by the diffuse immunohistochemical reaction to HHF35, and the presence of focal density and caveolas in some of the tumour cells by conventional electron microscopy. Immunohistochemically, most tumour cells had an undifferentiated nature, in which negative immunostaining for desmin, alpha-smooth muscle actin, and type IV collagen, and positive immunostaining for vimentin were observed. By the quick-freezing and deep-etching (QF-DE) method, these tumour cells revealed the loss of bundled actin and myosin filaments, which constitute desmin associated structures (focal densities and dense patchy areas). Their cytoplasm had many mitochondria and other cell organelles. The intermediate filaments (IFs), which were determined to be vimentin by immunohistochemistry, were observed in the inter-organellar spaces, and connected with these cell organelles. Actin filaments formed a meshwork structure and were distributed mainly in subplasmalemmal regions. Although a basal lamina was not detected by conventional electron microscopy, basal lamina-like structures, an association between the extracellular matrices and the cell membrane, were observed. Using the QF-DE method, three dimensional ultrastructural alterations of the cytoskeleton and extracellular matrix of the leiomyosarcoma were observed.

Actins↗