PubMed Health⌕ Search

Biomedical subjects

M Enomoto

Publications and source records attributed to M Enomoto.

At least 19 recordsLinked to original sources
PubMed2006

Enhancement of the Curie temperature by isomerization of diarylethene (DAE) for an organic-inorganic hybrid system: Co4(OH)7(DAE)0.5.3H2O.

Intercalation of an organic photochromic molecule into layered magnetic systems may provide multifunctional properties such as photomagnetism. To build up a photosensitive multifunctional magnet, an organic-inorganic hybrid system coupled with a photochromic diarylethene anion, 2,2'-dimethyl-3,3'-(perfluorocyclopentene-1,2-diyl)bis(benzo[b]thiophene-6-sulfonate) (DAE), and cobalt LDHs (layered double hydroxides), Co4(OH)7(DAE)0.5.3H2O, was synthesized by the anion exchange reaction between Co2(OH)3(CH3COO).H2O and DAE. In the dark and under UV-irradiated (313 nm) conditions, Co4(OH)7(DAE)0.5.3H2O with open and closed forms of DAE were obtained, respectively. The magnetic susceptibility measurements elucidated ferromagnetic intra- and interlayer interactions and Curie temperatures of TC = 9 and 20 K for cobalt LDHs with the open and closed forms of DAE, respectively. The enhancement of the Curie temperature from 9 to 20 K by substitution of the open form of DAE with the closed form of DAE as an intercalated molecule is attributed to the delocalization of the pi-electrons in the closed form of DAE, which enhances the interlayer magnetic interaction. The enhancement of the interlayer magnetic interaction induced by the delocalization of pi-electrons in intercalated molecules is strongly supported by the fact that the Curie temperature (26.0 K) of cobalt LDHs with (E,E)-2,4-hexadienedioate having a conjugated pi-electron system is enormously higher than that (7.0 K) of the cobalt LDHs with hexanedioate. By UV irradiation at 313 nm, Co4(OH)7(DAE)0.5.3H2O shows the photoisomerization of DAE from the open form to the closed one in the solid state, which leads to the enhancement of Curie temperature.

Journal Article↗
PubMed2005

Comparative study of two Japanese rhinoconjunctivitis quality-of-life questionnaires.

CONCLUSION: Two questionnaires were used to assess quality of life (QOL) in allergic rhinitis: the Japanese translation of the Rhino-conjunctivitis Quality of Life Questionnaire (RQLQJ) and an original Japanese QOL questionnaire (JRQLQ). Either questionnaire may be used to assess QOL depending on differences in target domains. OBJECTIVES: Although pollinosis is a common disease which has a major impact on patient QOL, no internationally standardized questionnaire has been available in Japan until now. The aim of this study was to compare two currently available QOL questionnaires for allergic rhinitis in Japan-the RQLQJ and JRQLQ-in terms of their appropriateness for clinical use and their psychometric properties. MATERIAL AND METHODS: A multicenter, inter-group, cross-sectional study was conducted in 187 adult symptomatic patients with Japanese cedar pollinosis in 2003. Patient scores on the two questionnaires were compared in terms of both overall and comparable domains. We also examined the acceptability, construct and reliability of both questionnaires. RESULTS: The questionnaires were highly correlated in terms of both overall and comparable domain scores. In addition, both questionnaires had equal and satisfactory psychometric validity, demonstrating that they are both useful tools for assessing QOL in rhinitis. However, when compared with each other, the JRQLQ focuses mainly on activities of daily life and is simpler, while the RQLQJ focuses mainly on rhinitis-related health and is more responsive.

Adult↗
PubMed2004

Identification and characterization of a reptilian GnRH receptor from the leopard gecko.

Gonadotropin-releasing hormone (GnRH) plays a pivotal role in the regulation of reproductive functions through interactions with its specific receptor. We describe the first molecular cloning and characterization of a full-length GnRH receptor (GnRHR) from the leopard gecko Eublepharis macularius. It has a distinct genomic structure consisting of five exons and four introns, compared with all the other reported GnRHR genes. A native GnRH form, cGnRH-II, stimulated inositol phosphate (IP) production in COS-7 cells transiently transfected with the GnRHR, in a dose dependent manner. The mRNA was expressed in all the tissues and organs examined. Molecular phylogenetic analysis revealed that the cloned GnRHR belongs to the type 2/nonmammalian I GnRHR. Low-expression levels were observed from the pituitary glands of reproductively active leopard geckos, indicating the possibility that there is at least one more type of GnRHR highly expressed in the pituitary gland for the gonadotropin secretion in this reptile.

Animals↗
PubMed2004

Effects of ribavirin combined with interferon-alpha 2b on viral kinetics during first 12 weeks of treatment in patients with hepatitis C virus genotype 1 and high baseline viral loads.

This study aimed to find how ribavirin increases viral disappearance in patients with hepatitis C virus (HCV) of genotype 1 and high baseline viral loads (>5.0 x 10(5) copies/mL) when given with interferon (IFN). Using the real-time quantitative polymerase chain reaction, we measured serum HCV in 20 patients during the first 12 weeks of therapy with IFN-alpha 2b and ribavirin. Controls were 10 similar patients given IFN-alpha 2b alone. IFN-alpha 2b was given at 6 MU daily for 2 weeks, and then three times weekly. Ribavirin was given at 600 or 800 mg daily. Serum HCV RNA decreased rapidly in the first phase, during the first 24 h of therapy (day 0), and more slowly in the early second phase (days 1-14). The median decrease was by 1.41 and 0.078 log 10/day in these two phases in the combination therapy group, and 0.90 and 0.081 log 10/day in the monotherapy group. The difference between groups in the first phase was not significant (P = 0.24), nor was that in the next phase (P = 0.68). Later in the second phase, between days 14 and 84, the median decrease was larger in the combination therapy group (0.030 log 10/day) than in the monotherapy group (0.015 log 10/day, P = 0.035). In patients with HCV genotype 1 and high viral loads, the effects of ribavirin with IFN-alpha appeared slowly, after the earliest days of treatment. A long-term favourable outcome of combination therapy may be associated with a rapid viral decline in this later phase of therapy.

Adult↗
PubMed2001

GnRH agonist Buserelin affects colony-forming efficiency of HHUA and Jurkat cells.

In this study, cell proliferation was examined at low and high cell densities, using HHUA and Jurkat cell lines as experimental models for the antiproliferative and proliferation-enhancing effects of GnRH agonist, Buserelin, respectively. For efficient evaluation of Buserelin activity at low cell density, the colony-forming efficiency assay was adopted. Buserelin markedly affected colony-forming efficiency in a dose-dependent manner at low cell density; however, Buserelin had no effect at high cell density. The conditioned medium of HHUA cells inhibited the Buserelin action, whereas that of Jurkat cells mimicked it. These results suggest that each cell line secretes some substances which regulate cell proliferation, and that these substances can also change the effects of Buserelin. The measurement of colony-forming efficiency is a very effective way of eliminating autocrine and/or paracrine effects, and is a highly sensitive method for measuring GnRH activity.

Animals↗
PubMed2001

Statins alter smooth muscle cell accumulation and collagen content in established atheroma of watanabe heritable hyperlipidemic rabbits.

BACKGROUND: Acute coronary syndromes often result from rupture of vulnerable plaques. The collagen content of plaques probably regulates their stability. This study tested whether HMG-CoA reductase inhibitors (statins) alter interstitial collagen gene expression or matrix metalloproteinase (MMP) levels in rabbit atheroma. METHODS AND RESULTS: We administered equihypocholesterolemic doses of pravastatin (a hydrophilic statin, 50 mg. kg(-1). d(-1), n=9), fluvastatin (a cell-permeant lipophilic statin, 20 mg. kg(-1). d(-1), n=10), or placebo (n=10) to mature Watanabe heritable hyperlipidemic rabbits for 52 weeks. The fluvastatin group achieved a much higher peak plasma concentration (23.7 micromol/L) than did the pravastatin group (1.3 micromol/L) under these conditions. Immunohistochemistry revealed that MMP-1, MMP-3, and MMP-9 expression by macrophages in the intima was lower in both the pravastatin and fluvastatin groups than in the placebo group, whereas there was no difference in macrophage numbers. Numbers of intimal smooth muscle cells (SMCs) (identified by immunohistochemistry) and expression of type I procollagen mRNA (detected by in situ hybridization), however, were significantly higher in the pravastatin group than in the fluvastatin group. Treatment with pravastatin, but not fluvastatin, preserved interstitial collagen content in vivo (detected by picrosirius red polarization). In vitro, fluvastatin, but not pravastatin, decreased numbers of rabbit and human aortic SMCs without altering procollagen I mRNA expression. CONCLUSIONS: This study showed that statins can reduce MMP expression in atheroma and that cell-permeant statins can decrease SMC number and collagen gene expression in vivo.

Animals↗
PubMed2001

Chemokine receptor expressions and responsiveness of cord blood T cells.

Chemokines and their receptors play a critical role in the selective attraction of various subsets of leukocytes. We examined the chemokine receptor expressions and responsiveness of cord blood (CB) T cells. Flow-cytometric analysis revealed that peripheral blood (PB) T cells expressed CCR-1, CCR-2, CCR-5, CCR-6, CXC chemokine receptor-3 (CXCR-3), and CXCR-4, while CB T cells expressed only CXCR-4 on their surface. Chemotactic migratory response of CB T cells to macrophage-inflammatory protein (MIP)-1alpha, monocyte chemoattractant protein-1, RANTES, MIP-3alpha, monokine induced by IFN-gamma, and IFN-gamma-inducible protein-10 was significantly impaired compared with those of PB T cells. In contrast, the ability of CB T cells to migrate to MIP-3beta, 6Ckine, and stromal cell-derived factor-1alpha was greater than that of PB T cells, and these events were correlated with the expression levels of CCR-7 and CXCR-4, respectively. Engagement of CD3 and CD28 specifically up-regulated CXCR-3 expression and chemotaxis to monokine induced by IFN-gamma and IFN-gamma-inducible protein-10, whereas this stimulation down-regulated CCR-7 expression and chemotaxis to MIP-3beta and 6Ckine in PB T cells, but not in CB T cells. These results suggest that PB T cells and CB T cells exhibit distinct chemokine responsiveness via different chemokine receptor repertoire.

Antibodies, Monoclonal↗
PubMed2001

Accessory spleen in the pelvis diagnosed by Tc-99m phytate scintigraphy.

We report a 58-year-old woman with an accessory spleen in the left side of the pelvis. She visited our outpatient clinic complaining of lower abdominal discomfort. Abdominal ultrasonography revealed a tumor 4 cm in diameter in the left side of the pelvis. Color Doppler ultrasonography demonstrated plentiful pulsating blood flow. Magnetic resonance angiography revealed that the blood supply for the tumor was from a branch of the splenic artery. Scintigraphy with Tc-99m phytate revealed accumulation of radioactivity concordant with a mass in the left side of the pelvis, and the spleen was normally visualized. These findings suggested that this tumor was an accessory spleen, and the patient underwent no further invasive procedures.

Female↗
PubMed2001

Does ascorbic acid prevent retinopathy during interferon therapy in patients with chronic hepatitis C?

PURPOSE: Ascorbic acid was administered to patients with chronic hepatitis C to elucidate the mechanism of onset of retinopathy during interferon (IFN) therapy, and its prevention. METHODS: The subjects were 62 patients with chronic hepatitis C who had been admitted to our hospital. For the IFN therapy, 6 MIU of natural IFN-alpha, or 10 MIU of recombinant human IFN-alpha 2b was administered every day for the first 2 weeks, followed by administration three times a week for 22 weeks. The patients were randomly assigned to a group receiving 600 mg/day of ascorbic acid or a group not receiving ascorbic acid (control group). The optic fundi were examined by ophthalmologists before the IFN therapy began and subsequently at weeks 2 and 4 and then every 4 weeks during the IFN therapy. RESULTS: Retinopathy was found in 9 of the 31 patients (29%) in the ascorbic acid-treated group and in 11 of the 31 patients (35%) in the control group. The cumulative incidence of hemorrhage in the ascorbic acid-treated group was lower than that in the control group during the IFN therapy, but the difference between the two groups was not significant (P = 0.186). The cumulative incidence of cotton-wool spots in the ascorbic acid-treated group was almost same as that in the control group during the IFN therapy. The median platelet counts before the therapy was begun were 11.8 x 10(4)/mm2 in the group with hemorrhage and 16.6 x 10(4)/mm2 in the group without, and the lowest platelet counts during IFN therapy were 7.3 x 10(4)/mm3 in the group with hemorrhage and 9.5 x 10(4)/mm3 in the group without, indicating significantly lower values in the group with hemorrhage (P = 0.018 and P = 0.020, respectively). The lowest platelet counts during IFN therapy were 7.4 x 10(4)/mm3 in the group with cotton-wool spots and 9.7 x 10(4)/mm3 in the group without, indicating a significantly lower value in the group with cotton-wool spots (P = 0.036). CONCLUSIONS: Ascorbic acid was not considered to be useful for the prevention of the retinopathy associated with IFN therapy in patients with chronic hepatitis C.

Adult↗
PubMed2001

Fibromuscular cap composition is important for the stability of established atherosclerotic plaques in mature WHHL rabbits treated with statins.

We examined the relationship between plaque vulnerability and fibromuscular cap composition using hydrophilic pravastatin and lipophilic fluvastatin. WHHL rabbits aged 10 months were given pravastatin (50 mg/kg) or fluvastatin (20 mg/kg) for 52 weeks. The atherosclerotic lesions were immunohistochemically or conventionally stained and the components were analyzed with a color image analyzer. Compared with the control group, the plasma cholesterol levels were decreased by about 25% in both statin groups. Pravastatin decreased the lipid components (macrophages+extracellular lipids) in whole aortic plaques by 34% and the fibrous caps of coronary plaques by 55%. Fluvastatin decreased the fibromuscular components (smooth muscle cells+collagen fibers) in whole aortic plaques and in the fibromuscular caps of the aortic and coronary plaques. In the pravastatin group, the vulnerability index, the ratio of (lipid components)/(fibromuscular components), was decreased in whole aortic plaques by 28% and in the fibromuscular caps of coronary lesions by 61%, while the indexes were increased in the fluvastatin group. The incidence of vulnerable plaques was decreased by 74% in the coronary plaques of the pravastatin group. Our results suggest that the stability of atheromatous plaques was improved due to a decrease of the lipid components and vulnerability index of the fibromuscular cap by pravastatin.

Animals↗
PubMed2001

Comparison of real-time quantitative polymerase chain reaction with three other assays for quantitation of hepatitis C virus.

BACKGROUND AND AIMS: Evaluation of serum levels of hepatitis C virus (HCV) is important for predicting the response to interferon treatment and monitoring its therapeutic efficacy. The aim of this study was to evaluate real-time quantitative polymerase chain reaction (PCR) as a method for the measurement of HCV-RNA. METHODS: The subjects were 50 patients with chronic hepatitis C: 36 with genotype 1b, eight with genotype 2a, and six with genotype 2b. Samples were tested for HCV-RNA by using real-time quantitative PCR with the ABI Prism 7700 sequence detection system, a branched DNA signal amplification assay, and an Amplicor monitor test; and for HCV core protein by using a fluorescent enzyme immunoassay. RESULTS: The detection range of the real-time quantitative PCR was between 10(1)-10(8) copies/mL of HCV-RNA. Hepatitis C virus RNA was detectable in all 50 samples by the use of real-time quantitative PCR, but was undetectable in 14 samples by the use of a branched DNA assay and in two samples by using the Amplicor monitor test; HCV core protein was undetectable in three samples. A significant correlation was found between the results of real-time quantitative PCR and those of the three other assays: branched DNA assay (r = 0.837, P < 0.0001), Amplicor monitor test (r = 0.853, P < 0.0001), and HCV core protein concentrations (r = 0.549, P < 0.0001). CONCLUSIONS: Our results showed that the real-time quantitative PCR was a highly sensitive assay for the measurement of HCV-RNA.

Adult↗
PubMed2001

Method to detect substitutions in the interferon-sensitivity-determining region of hepatitis C virus 1b for prediction of response to interferon therapy.

Substitutions deduced by direct sequencing in the interferon-sensitivity-determining region (ISDR) of hepatitis C virus (HCV) are related to patients' responses to interferon (IFN), but sequencing is time consuming and results are only for the dominant virus. We developed a rapid method to detect such changes. With serum from 50 patients with chronic hepatitis C (genotype 1b) given IFN-alpha, a way to detect changes in ISDR by hybridization with oligonucleotide probes that had a prototype nucleotide sequence of HCV-J was established. Hybridization intensity was expressed as optical density (OD(NS5A)). The method was checked with serum from 100 more patients. In the study of 50 patients, all 21 with the prototype sequences had a high OD(NS5A) (> or = 0.4), and all 8 patients with a mutant-type sequence had low values (< or = 0.2). Twelve (95% confidence interval, 36-81%) of 20 patients with OD(NS5A) of <0.4 and 2 (1%-22%) of 30 patients with OD(NS5A) > or = 0.4 had complete responses (CR). All nine (66%-100%) patients with OD(NS5A) <0.4 and little HCV RNA (<100 kIU/mL) had CR, but none (0%-14%) of the 24 patients with high values from both predictors had CR. In the study of 100 patients, OD(NS5A) and the HCV RNA level were independent predictors of the effects of IFN. By multivariate analysis, the odds ratio for a CR in patients with OD(NS5A) of > or = 0.4 was 0.015 (0. 001-0.190) compared with the other patients (P =.001). In conclusion, our method should be useful in identification of prototype strains, which generally resist IFN therapy.

Amino Acid Substitution↗
PubMed2001

Signaling events following chemokine receptor ligation in human dendritic cells at different developmental stages.

Responsiveness of dendritic cells (DC) to inflammatory CC chemokines is down-regulated during their maturation. We analyzed the mechanism underlying these events. Cell-surface expression of CC chemokine receptor (CCR)-1, -3 and -5 was increased during differentiation of immature DC (iDC) from monocytes. In contrast, these expressions were decreased during development of iDC into mature DC (mDC) to levels similar to those of monocytes. Transcriptional expression of CCR-1, -3 and -5 was increased during differentiation of iDC from monocytes, while the expression was decreased during development of iDC into mDC. Expression of CCR-7 transcript was detected in mDC, but not in monocytes or iDC. Both monocytes and iDC, but not mDC, migrated in response to inflammatory CC chemokines such as regulated on activation normal T cell expressed and secreted (RANTES)/CCL5, whereas mDC, but not monocytes or iDC, migrated to macrophage inflammatory protein (MIP)-3ss/CCL19. Receptor engagement of monocytes or iDC by RANTES (for CCR-1, -3 and -5) resulted in protein tyrosine phosphorylation events including activation of focal adhesion kinase as well as mitogen-activated protein kinase, whereas this stimulation induced little activation of these molecular events in mDC when compared with monocytes or iDC. On the other hand, stimulation with MIP-3ss (for CCR-7) induced tyrosine phosphorylation events in mDC, but not in monocytes or iDC. These results suggest that the down-regulation of cell-surface expression of CCR and of their downstream signaling events may be involved in the reduced chemotaxis of DC to inflammatory CC chemokines during their maturation.

Cell Differentiation↗
PubMed2001

Enhancement of migratory and aggregate activities of human peripheral blood monocyte-derived dendritic cells by stimulation with RANTES.

We examined the effects of various chemokines on the functional activation of granulocyte-macrophage colony-stimulating factor (GM-CSF) plus interleukin-4 (IL-4)-generated human peripheral blood monocyte-derived immature dendritic cells (iDC). Stimulation of iDC with regulated on activation normal T cell expressed and secreted (RANTES) resulted in the promotion of their chemotactic migratory capacity in response to RANTES when compared with that of unstimulated cells. TNF-alpha induced a homotypic aggregated cluster formation of iDC in a dose-dependent manner, whereas the combination of TNF-alpha and RANTES exhibited more potent induction. IDC stimulated with RANTES were more efficient than unstimulated iDC in the production of endogenous RANTES. Treatment of iDC with the combination of TNF-alpha and RANTES was just little effective for the enhancement of allogeneic T-cell stimulatory capacity as compared with that of TNF-alpha treated iDC. These results suggest that endogenous secretions of RANTES from iDC stimulated with RANTES be potentially involved in RANTES-induced changes of properties with respect to morphology and function.

Cell Movement↗
PubMed2001

Stability of atheromatous plaque affected by lesional composition: study of WHHL rabbits treated with statins.

We examined how lesional composition is related to the stability of coronary plaques. WHHL rabbits (12 months old) were given pravastatin and fluvastatin orally for 52 weeks. Both statins decreased plasma cholesterol levels by about 25%, but the suppressive effects on the degree of coronary plaques were mild. Macrophage (Mphi) contents in fibromuscular cap regions were decreased by pravastatin, and smooth muscle cell (SMC) contents in those were decreased by fluvastatin. The plaque vulnerability index was low in Mphi)-poor plaques, but high in SMC-poor plaques. Our results suggest that reduction in M(phi)s in the fibromuscular cap is related to plaque stabilization and that reduction in SMCs in the fibromuscular cap is related to plaque destabilization.

Animals↗