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Yutaka Morita

Publications and source records attributed to Yutaka Morita.

At least 19 recordsLinked to original sources
PubMed2006

[Cost-effectiveness of fluticasone propionate for asthma episodes in Japanese patients with asthma--Fluticasone Investigation of Asthma Episode (FINE) study].

BACKGROUND: To discuss and estimate the economic benefits gained by fluticasone propionate (FP) for patients with asthma over hospitalization, emergency room visit, unscheduled visit, and absence (representative by asthma-related episode). METHOD: Asthma-related episodes in pre and post 6 months of FP use were derived from a survey of FP on asthma-related episodes (FINE study). Medical cost was evaluated by macro-cost estimate and productivity loss by human capital approach. RESULTS: Discussion of asthma-related episodes in-between before and after the use of FP in eight hundred ninety-eight valuable subjects revealed that FP use significantly reduced asthma-related episodic costs of approximately 120,000 yen (p<0.001), whereas total drug acquisition costs for being newly consumed FP, leukotriene receptor antagonists, inhaled short-acting beta2 agonists, etc were significantly increased by approximately 16,000 yen. Moreover, while significantly avoiding productivity loss of approximately about 35,000 yen it totally provided cost-savings of about 70,000 yen at the patients' viewpoint. When sensitivity analyses were performed by adjusting the confounding factors using analysis of covariance, the aforementioned base case results might be persistent. For safety of FP, some adverse events related to the use of FP were identified of about 2.0%, and there were not any serious ones at all. CONCLUSION: The economic evaluation of FP demonstrated that it is sufficient, whereas an acquisition cost was increased. Use of FP economically impacts on Japanese society and patients.

Adult↗
PubMed2005

TRAF7 sequesters c-Myb to the cytoplasm by stimulating its sumoylation.

Small ubiquitin-related modifiers (SUMOs) are proteins that are posttranslationally conjugated to diverse proteins. The c-myb proto-oncogene product (c-Myb) regulates proliferation and differentiation of hematopoietic cells. PIASy is the only known SUMO E3 ligase for c-Myb. Here, we report that TRAF7 binds to c-Myb and stimulates its sumoylation. TRAF7 bound to the DNA-binding domain of c-Myb via its WD40 repeats. TRAF7 has an E3 ubiquitin ligase activity for self-ubiquitination, but TRAF7 also stimulated the sumoylation of c-Myb at Lys-523 and Lys-499, which are the same sites as those used for PIASy-induced sumoylation. TRAF7 inhibited trans-activation induced by wild-type c-Myb, but not by the sumoylation site mutant of c-Myb. The expression of both c-myb and TRAF7 was down-regulated during differentiation of M1 cells. Endogenous TRAF7 localized to both the cytoplasm and nucleus of M1 cells. Consistent with this, significant amounts of sumoylated c-Myb were found in the cytoplasm of M1 cells, whereas nonsumoylated c-Myb was found predominantly in the nucleus. Overexpressed TRAF7 was localized in the cytoplasm of CV-1 cells, and sequestered c-Myb and SUMO1 in the cytosol, whereas PIASy was localized in the nucleus. Thus, TRAF7 negatively regulates c-Myb activity by sequestering c-Myb to the cytosol via sumoylation.

Animals↗
PubMed2004

Effects of imposed bending on microtubule sliding in sperm flagella.

The movement of eukaryotic flagella is characterized by its oscillatory nature. In sea urchin sperm, for example, planar bends are formed in alternating directions at the base of the flagellum and travel toward the tip as continuous waves. The bending is caused by the orchestrated activity of dynein arms to induce patterned sliding between doublet microtubules of the flagellar axoneme. Although the mechanism regulating the dynein activity is unknown, previous studies have suggested that the flagellar bending itself is important in the feedback mechanism responsible for the oscillatory bending. If so, experimentally bending the microtubules would be expected to affect the sliding activity of dynein. Here we report on experiments with bundles of doublets obtained by inducing sliding in elastase-treated axonemes. Our results show that bending not only "switches" the dynein activity on and off but also affects the microtubule sliding velocity, thus supporting the idea that bending is involved in the self-regulatory mechanism underlying flagellar oscillation.

Animals↗
PubMed2004

[Studying chemistry of heterocyclic compounds--some rearrangement reactions of indoles and the related compounds].

Indole alkaloids are one of the most interesting research fields. The chemistry of monoterpenoid indole alkaloids, in particular, offers many skeletal rearrangement reactions including terpenoid rearrangements. The author describes those compounds encountered or connected with in his research, including iridoids, indole alkaloids, adamantanes found in nature, and oxyindoles that are correlated with rearrangements.

Chemistry, Organic↗
PubMed2004

Alpha-1 antitrypsin deficiency with severe pulmonary emphysema.

Alpha-1 antitrypsin (AAT) deficiency is a hereditary disorder characterized by an early onset of emphysema. While this disease is common in the Caucasian population, it is quite rare in Japan. To date, only 15 traits have been reported and it can be speculated that many cases of this genetic deficiency may have been overlooked. We report an additional case of AAT deficiency with severe emphysema that is genetically determined as S(iiyama) variant by allele-specific polymerase chain reaction (PCR) analysis.

Alleles↗
PubMed2003

Concentrations of interferon-gamma-induced protein-10 (IP-10), an antiangiogenic substance, are decreased in peritoneal fluid of women with advanced endometriosis.

PROBLEM: To assess whether interferon-gamma-induced protein-10 (IP-10), a chemokine that has antiangiogenic activities, may be involved in the pathogenesis of endometriosis. METHOD OF STUDY: A total of 120 patients undergoing laparoscopy for pain and/or infertility were recruited, and peritoneal fluid (PF) and bone marrow derived cells in PF were collected. Concentrations of IP-10 in PF were measured with a specific enzyme-linked immunosorbent assay. Expression of IP-10 and IP-10 receptor, CXCR3, in bone marrow derived cells in PF, peritoneum and endometriotic cells was analyzed by reverse transcription-polymerase chain reaction. RESULTS: All of the PF samples examined contained detectable concentrations of IP-10. In women with advanced stages of endometriosis, IP-10 concentrations in PF were significantly lower than those of women in early stages (P = 0.02). The IP-10 concentrations in women with advanced endometriosis also appeared to be lower than those without endometriosis although the difference was statistically marginal (P = 0.06). The expression of both IP-10 and CXCR3 was clearly detected in the bone marrow derived cells in PF, peritoneum and endometriotic stromal cells. CONCLUSIONS: Decreased concentrations of IP-10 in PF from women with advanced stages of endometriosis may imply that the peritoneal environment of these women is permissive to the development of the disease by enhancing angiogenesis and/or modulating inflammatory/immunological responses.

Adult↗
PubMed2003

Induction of basophil desensitization in physiological medium: enhancement after IgE-dependent upregulation of surface IgE binding on basophils.

BACKGROUND: Although the ability of basophils to release mediators, called releasability, may be an important aspect which influences the proinflammatory role of these cells, clinical approaches aiming at the depletion of the releasability have not been established. We examined whether the desensitization procedure in Ca(2+)-containing physiological conditions can make basophils completely unresponsive to IgE-mediated stimulation, and whether basophil desensitization is affected by the surface IgE levels. METHODS: Human peripheral blood basophils were cultured with low concentrations of anti-IgE antibody or recombinant mite allergen. Following culture, cells were stimulated and their histamine release was measured. RESULTS: Culturing with mite allergen or anti-IgE antibody below threshold concentrations induced potent desensitization in basophils. The desensitizing effect of anti-IgE was dose- and time-dependent; IgE-dependent releasability was completely suppressed when basophils were incubated with a near-threshold concentration of anti-IgE for > or= 4 h. In the continuous presence of subthreshold doses of anti-IgE, basophils remained desensitized even after 3 days. Basophils which had undergone an increase in surface IgE levels after 24-hour culture with IgE demonstrated enhanced desensitization. CONCLUSIONS: Near-threshold stimulation in physiological medium can affect basophils, thereby inducing complete and sustained deprivation of releasability without triggering degranulation. Basophil desensitization is regulated by their surface IgE levels. Induction of full desensitization may represent a potentially important therapeutic strategy for IgE-mediated allergic diseases in which basophils play pathogenic roles.

Animals↗
PubMed2002

Bisphenol A induces apoptosis and G2-to-M arrest of ovarian granulosa cells.

We investigated the impact of bisphenol A (BPA) on murine ovarian granulosa cells. Ovarian granulosa cells were cultured with 100 fM to 100 microM BPA for 24 h to 72 h. BPA decreased granulosa cell viability in a dose- and time-dependent manner. The lowest concentration that induced a significant decrease was 100 pM (89.2 +/- 4.0% of the control). TUNEL analysis demonstrated that treatment with BPA increased apoptosis of granulosa cells in a dose- and time-dependent manner. In addition, flow cytometry analyses revealed that treatment with BPA resulted in G2-to-M arrest, which was most prominent at 48 h. BPA increased the expression of Bax and concomitantly decreased the expression of Bcl2 at both protein and mRNA levels of granulosa cells. These findings suggest that low, presumably environmentally relevant doses of BPA, decrease the viability of granulosa cells by inducing apoptosis and G2-to-M arrest. Up-regulation of Bax and down-regulation of Bcl2 were suggested to be involved in this apoptotic effect.

Animals↗
PubMed2002

Human chorionic gonadotropin combined with progesterone for luteal support improves pregnancy rate in patients with low late-midluteal estradiol levels in IVF cycles.

PURPOSE: To investigate how late-midluteal estradiol levels relate to the pregnancy outcome in IVF cycles, and to assess whether human chorionic gonadotropin (hCG) for luteal support benefits the pregnancy outcome of patients with low late-midluteal estradiol levels. METHODS: The pregnancy rate of 436 women undergoing first IVF cycles with long protocol and luteal support with progesterone alone were analyzed. Unsuccessful women with low late-midluteal estradiol levels (< 100 pg/mL) proceeded with the exploratory second IVF cycles where they were randomly given with either progesterone alone (P protocol) or hCG +progesterone (P+hCG protocol) for luteal support. RESULTS: Pregnancy rate in women with low late-midluteal estradiol levels was significantly lower compared to that with medium (100-500 pg/mL) and high (> 500 pg/mL) levels (13.3, 26.8, and 36.3%, respectively). P+hCG protocol increased late-midluteal estradiol levels and produced a significantly higher pregnancy rate (31.7%) than P protocol (13.7%). CONCLUSIONS: hCG in combination with progesterone for luteal support was suggested to benefit women undergoing IVF with low late-midluteal estradiol levels.

Adult↗
PubMed2002

A functional study on CysLT(1) receptors in human eosinophils.

BACKGROUND: The cysteinyl leukotrienes (CysLTs) mediate their biological actions through two receptors: CysLT(1) receptor and CysLT(2) receptor. OBJECTIVE: This study was undertaken to examine the direct effects of CysLTs on eosinophils, such as chemotaxis and degranulation, focusing on CysLT(1). METHODS: Eosinophils were isolated from venous blood from normal volunteers who had no history of allergy (purity >99%). They were subjected to reverse transcription-PCR analysis and flow-cytometric analysis for CysLT(1). Binding assays were performed with [(3)H]LTD(4). Purified eosinophils loaded with Fura-2 acetoxymethyl ester were stimulated with CysLTs, and Ca(2+) influx was measured. Eosinophil migration in response to CysLTs was measured using a 96-well multiwell Boyden chamber. Eosinophils were treated with LTD(4) at 10(-6) M for 60 min followed by incubation for 4 h at 37 degrees C in the presence or absence of IL-5 and eosinophil-derived neurotoxin (EDN) release was evaluated. RESULTS: The expression of the mRNA and protein of CysLT(1) on eosinophils and [(3)H]LTD(4)-specific binding to eosinophils were observed. Neither Th1 cytokine (IFN-gamma) nor Th2 cytokines (IL-4 or IL-5) affected CysLT(1) expression in eosinophils. CysLTs induced an increase in intracellular free Ca(2+) in eosinophils via CysLT(1), as suggested by the efficient inhibition by a CysLT(1) antagonist, pranlukast, in addition to the rank order of potency being LTD(4), LTC(4) and LTE(4). LTD(4) stimulated eosinophils to migrate at 10(-6) M via CysLT(1). LTE(4) also induced significant eosinophil migration at 10(-6) M. LTD(4) enhanced EDN release induced by IL-5 via CysLT(1). CONCLUSION: CysLTs induce migration and enhance degranulation in eosinophils via CysLT(1). Accordingly, interaction of CysLTs and CysLT(1) on eosinophils has the potential to play a prominent role in the pathophysiology of asthma.

Calcium↗
PubMed2002

IgG-mediated signal transduction in canine mastocytoma-derived cells.

BACKGROUND: We have reported canine cutaneous mastocytoma-derived cells named CM-MC sensitized with monomeric IgG released histamine upon anti-IgG stimulation. However, IgG or IgE-mediated signal transduction in the cells remains to be examined. METHODS: Monomeric IgG-binding to cells was measured by flow cytometry using FITC-anti-IgG. IgG-mediated protein tyrosine phosphorylation was studied by Western blotting using anti-phosphotyrosine antibody. We monitored the intracellular Ca(2+) concentration ([Ca(2+)](i)) when IgG-primed cells were activated with anti-canine IgG. Release of Ca(2+) from intracellular stores was analyzed with thapsigargin in the absence of extracellular Ca(2+). The Ca(2+) entry via store-operated Ca(2+) channel from the external environment was characterized using Ba(2+), Ni(2+) and EGTA. Cells sensitized with canine serum abundant in IgG and IgE or heat-inactivated serum were activated by anti-canine IgG or anti-canine IgE. The effect of extracellular Ca(2+) and reaction time on IgG-mediated histamine release was examined. Staurosporine and ER-27319 were used to clarify the IgG-mediated protein tyrosine phosphorylation. RESULTS: Abundant IgG-binding sites on the cell were detected by FACS analysis. Anti-IgG induced rapid protein tyrosine phosphorylation and [Ca(2+)](i) elevation. When extracellular Ca(2+) was excluded by EGTA, a mild and transient increase in [Ca(2+)](i) was observed, indicating the release of Ca(2+) from anti-IgG-sensitive intracellular Ca(2+) stores. The constant Ba(2+) entry from external environment proved the Ca(2+) influx occurred mainly via a store-operated Ca(2+) channel which was inhibited by Ni(2+) and EGTA. Canine serum-sensitized cells showed a rapid and sustained increase in [Ca(2+)](i) upon both anti-IgG and anti-IgE stimulation. The [Ca(2+)](i) elevation induced by anti-IgE was decreased in the cells sensitized with heat-inactivated serum. Histamine release from CM-MCs was absolutely dependent on extracellular Ca(2+), and reached equilibrium within 5 min. Staurosporine inhibited the tyrosine phosphorylation of 38-, 65-, 70-, 80-kD proteins. ER-27319 inhibited the tyrosine phosphorylation of 38- and 70-kD proteins. Staurosporine also inhibited IgG-mediated [Ca(2+)](i) elevation and histamine release in a dose-dependent manner. CONCLUSIONS: Canine cutaneous mastocytoma-derived (CM-MC) cells were activated by both IgG- and IgE-mediated mechanisms. IgG-mediated protein tyrosine phosphorylation and Ca(2+) influx were similar to those mediated by IgE. CM-MC cells are useful for the study of allergic inflammation caused by IgG-dependent mechanisms.

Acridines↗
PubMed2002

Inward rectifier K(+) current in human bronchial smooth muscle cells: inhibition with antisense oligonucleotides targeted to Kir2.1 mRNA.

Inward rectifier K(+) (Kir) channels play an important role in forming membrane potential and then modulating muscle tone in certain types of smooth muscles. In cultured human bronchial smooth muscle cells (hBSMCs), Kir current was identified using whole-cell voltage clamp techniques and explored by using RT-PCR analysis of mRNA, Western blotting, and antisense oligonucleotide methods to block the synthesis of Kir channel protein. The K(+) current with strong inward rectification and high K(+) ion selectivity was observed. The current was unaffected by 4-aminopyridine, glibenclamide, and charybdotoxin, and hardly inhibited by tetraethylammonium, but was potently inhibited by extracellular Ba(2+). The IC(50) value of external Ba(2+) was approximately 1.3 microm. RT-PCR analysis of mRNA showed transcripts for Kir2.1, but not Kir1.1, Kir2.2, or Kir2.3. Treatment of cells with antisense oligonucleotides targeted to Kir2.1 resulted in a decrease in the current density of the Kir current and Kir protein expression, as compared with the mismatch-treated cells, whereas the current density of 4-AP-sensitive K(+) currents (K(V)) remained unaffected. The application of Ba(2+) markedly depolarized the membrane. These results demonstrate that Kir channel is present in human bronchial smooth muscle cells, and the Kir2.1 gene encodes the Kir channel protein in these cells.

Bronchi↗
PubMed2002

Ligand activation of the aromatic hydrocarbon receptor transcription factor drives Bax-dependent apoptosis in developing fetal ovarian germ cells.

We recently reported that a targeted disruption of the gene encoding the aromatic hydrocarbon receptor (AHR) in mice reduces fetal oocyte apoptosis, leading to a 2-fold increase in the number of primordial follicles endowed at birth. Although the identity of the natural ligand(s) for the AHR remains to be unequivocally established, these findings indicate that the level of AHR function is an important physiological determinant of how many oocytes will succumb to apoptosis during development of the fetal ovaries. Furthermore, the AHR is a well established receptor for polycyclic aromatic hydrocarbons (PAHs), a class of ubiquitous environmental chemicals known to cause the death of female germ cells in fetal life. Given the possibility that the AHR serves as a key mediator of fetal oocyte death under both physiological and pathological situations, this study was conducted to more fully examine the impact of PAH-AHR interaction on fetal ovarian germ cells. In addition, experiments were designed to begin identification of the mechanism(s) by which ligand activation of the AHR induces prenatal oocyte depletion after transplacental exposure of fetuses to PAHs in vivo. Embryonic d 13.5 murine fetal ovaries cultured in the presence of PAHs exhibited a high level of germ cell loss via apoptosis that was prevented by the selective AHR antagonist, alpha-napthoflavone (ANF). Immunohistochemical analysis revealed an accumulation of Bax protein in germ cells of fetal ovaries exposed to PAHs before the onset of apoptosis, whereas cotreatment with ANF inhibited the induction of Bax expression. The functional importance of increased Bax expression to the cytotoxic response was confirmed by findings that fetal ovarian germ cell loss caused by in utero exposure of wild-type female fetuses to PAHs was not observed in Bax-deficient female fetuses exposed in parallel. We conclude that a central role exists for the AHR in transducing the actions of PAHs in fetal ovarian germ cells, and that the proapoptotic Bcl-2 family member, Bax, is a required mediator of PAH-induced oocyte loss in female fetuses exposed to PAHs in utero.

9,10-Dimethyl-1,2-benzanthracene↗