159 results on '"Sakamoto, K."'
Search Results
2. Observation and Evaluation of Plastic Collapse for Double-Notch Pipe.
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Suzuki, R., Matsubara, M., Sakamoto, K., Suzuki, M., Shiraishi, T., Yanagihara, S., Izawa, S., and Wakai, T.
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AUSTENITIC stainless steel ,CENTER of mass ,SHEARING force ,STRUCTURAL failures ,PLASTIC films - Abstract
The plastic collapse behavior and strength were investigated for an austenitic stainless steel pipe with two 90° through-wall notches perpendicular to the pipe axis direction. Double-notch specimens with various notch separation distances were coated with photo-plastic film. Arbitrary combined axial tensile and bending loads were applied to the specimens. Changes in the photoplastic fringe pattern were observed during the tests to investigate the plastic collapse behavior. The plastic collapse strength was evaluated using a model based on an elastic-perfectly plastic body. The photo-plastic fringe patterns at the experimental plastic collapse point differed based on the loading history. Thus, the plastic collapse behavior depends on the loading history. In addition, the plastic collapse strength differed based on the loading history and hardly depended on the notch separation distance. The experimental plastic collapse occurred before reaching the theoretical plastic point for only some pure tension loading tests. Thus, the model analysis based on an elastic-perfectly plastic body used in this study might give an unconservative estimate for the plastic collapse of a stainless steel pipe subjected to a pure tension load. [ABSTRACT FROM AUTHOR]
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- 2016
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3. Heating Effects in Overmoded Corrugated Waveguide for ITER.
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Anderson, J., Doane, J., Grunloh, H., Callis, R., Ikeda, R., Oda, Y., Takahashi, K., and Sakamoto, K.
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WAVEGUIDES ,ELECTRON cyclotron resonance heating - Abstract
The latest testing of International Thermonuclear Experimental Reactor (ITER)-class electron cyclotron heating (ECH) transmission line components at the Japan Atomic Energy Agency (JAEA) has revealed regions of significant heating. Temperature measurements taken along sections of the waveguide wall during a 350 kW, 500-s gyrotron pulse are higher than previously recorded, up to nearly 70 °C above room temperature in some cases. One difference between these results and previous measurements is that the heating occurs in areas far away from miter bends (>1 m), further than higher-order-mode decay lengths. The estimated ohmic losses are large enough that they may be potentially damaging at ITER power levels. The explanation is traced back to misalignment of upstream components created by heating effects under high-power conditions. These misalignments cause mode conversions from the desired HE mode to low-order LP modes. As the combination of modes propagate forward in the transmission line, the field interactions lead to localized hot spots along the waveguide wall. The heating could have implications for the design of ECH components as well as the layout of transmission lines at ITER. Furthermore, the effects are discovered to be dependent on polarization since the LP even mode has higher loss than the LP odd mode. This discovery leads to a novel way of estimating mode purity in the waveguide. By applying the method to the current data set, the estimated HE content in the waveguide is 93 % upstream from the misalignment and 85 % downstream. [ABSTRACT FROM AUTHOR]
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- 2016
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4. Magneto-optical trapping of radioactive atoms for test of the fundamental symmetries.
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Kawamura, Hirokazu, Ando, S., Aoki, T., Arikawa, H., Harada, K., Hayamizu, T., Inoue, T., Ishikawa, T., Itoh, M., Kato, K., Köhler, L., Mathis, J., Sakamoto, K., Uchiyama, A., and Sakemi, Y.
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ION traps ,MAGNETOOPTICS ,FRANCIUM ,SYMMETRY (Physics) ,STANDARD model (Nuclear physics) - Abstract
We are planning test experiments of fundamental symmetries based on the intrinsic properties of francium. It is expected that the laser cooling and trapping of francium will produce precision measurements. The pilot experiment using rubidium was performed with the goal of francium trapping. The ion beam generated with a francium ion source was investigated using a Wien filter. Each piece of equipment still must be studied in more detail, and the equipment should be upgraded in order to trap radioactive atoms. [ABSTRACT FROM AUTHOR]
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- 2015
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5. miR-9-3p plays a tumour-suppressor role by targeting TAZ (WWTR1) in hepatocellular carcinoma cells.
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Higashi, T, Hayashi, H, Ishimoto, T, Takeyama, H, Kaida, T, Arima, K, Taki, K, Sakamoto, K, Kuroki, H, Okabe, H, Nitta, H, Hashimoto, D, Chikamoto, A, Beppu, T, and Baba, H
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LIVER cancer ,MICRORNA ,CELLULAR signal transduction ,GENETIC overexpression ,CANCER prognosis ,POLYMERASE chain reaction ,CELL lines ,THERAPEUTICS - Abstract
Background:The inactivation of the Hippo pathway lead to TAZ (PDZ-binding motif)/YAP (yes-associated protein) overexpression, and is associated with worse prognostic outcomes in various cancers including hepatocellular carcinoma (HCC). Although there are several reports of microRNA (miR) targeting for YAP, miR targeting for TAZ remains unclear. The aim of this study is to identify the miR targeting TAZ expression in HCC.Methods:MicroRNA expression was analysed using the Human miFinder 384HC miScript miR PCR array, and was compared between low and high TAZ expression cell lines. Then, we extracted miR-9-3p as a tumour-suppressor miR targeting TAZ. We examined the functional role of miR-9-3p using miR-9-3p mimic and inhibitor in HCC cell lines).Results:In HCC cell lines and HCC clinical samples, there was the inverse correlation between miR-9-3p and TAZ expressions. TAZ expression was induced by treatment of miR-9-3p inhibitor and was downregulated by treatment of miR-9-3p mimic. Treatment of miR-9-3p mimic inhibited cell proliferative ability with downregulated phosphorylations of Erk1/2, AKT, and β-catenin in HLF. Inversely, treatment of miR-9-3p inhibitor accelerated cell growth compared with control in HuH1.Conclusions:MicroRNA-9-3p was identified as the tumour-suppressor miR targetting TAZ expression in HCC cells. [ABSTRACT FROM AUTHOR]
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- 2015
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6. Replication factor C3 is a CREB target gene that regulates cell cycle progression through the modulation of chromatin loading of PCNA.
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Chae, H-D, Mitton, B, Lacayo, N J, and Sakamoto, K M
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PROLIFERATING cell nuclear antigen ,TRANSCRIPTION factors ,CHROMATIN ,NUCLEAR proteins ,ACUTE myeloid leukemia ,CELL lines ,REPLICATION factors (Biochemistry) - Abstract
CREB (cyclic AMP response element-binding protein) is a transcription factor overexpressed in normal and neoplastic myelopoiesis and regulates cell cycle progression, although its oncogenic mechanism has not been well characterized. Replication factor C3 (RFC3) is required for chromatin loading of proliferating cell nuclear antigen (PCNA) which is a sliding clamp platform for recruiting numerous proteins in the DNA metabolism. CREB1 expression, which was activated by E2F, was coupled with RFC3 expression during the G1/S progression in the KG-1 acute myeloid leukemia (AML) cell line. There was also a direct correlation between the expression of RFC3 and CREB1 in human AML cell lines as well as in the AML cells from the patients. CREB interacted directly with the CRE site in RFC3 promoter region. CREB-knockdown inhibited primarily G1/S cell cycle transition by decreasing the expression of RFC3 as well as PCNA loading onto the chromatin. Exogenous expression of RFC3 was sufficient to rescue the impaired G1/S progression and PCNA chromatin loading caused by CREB knockdown. These studies suggest that RFC3 may have a role in neoplastic myelopoiesis by promoting the G1/S progression and its expression is regulated by CREB. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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7. Economic evaluation of a preemptive treatment strategy for invasive fungal infection in neutropenic patients with hematological diseases.
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Kimura, S.-I., Murata, T., Akahoshi, Y., Nakano, H., Ugai, T., Wada, H., Yamasaki, R., Ishihara, Y., Kawamura, K., Sakamoto, K., Ashizawa, M., Sato, M., Terasako-Saito, K., Nakasone, H., Kikuchi, M., Yamazaki, R., Kako, S., Kanda, J., Tanihara, A., and Nishida, J.
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COMMUNICABLE disease treatment ,MYCOSES ,NEUTROPENIA ,BLOOD diseases ,MEDICAL care costs ,VORICONAZOLE ,PATIENTS ,THERAPEUTICS - Abstract
We compared the expected medical costs of empirical and preemptive treatment strategies for invasive fungal infection in neutropenic patients with hematological diseases. Based on the results of two clinical trials with different backgrounds reported by Oshima et al. [J Antimicrob Chemother 60(2):350-355; Oshima study] and Cordonnier et al. [Clin Infect Dis 48(8):1042-1051; PREVERT study], we developed a decision tree model that represented the outcomes of empirical and preemptive treatment strategies, and estimated the expected medical costs of medications and examinations in the two strategies. We assumed that micafungin was started in the empirical group at 5 days after fever had developed, while voriconazole was started in the preemptive group only when certain criteria, such as positive test results of imaging studies and/or serum markers, were fulfilled. When we used an incidence of positive test results of 6.7 % based on the Oshima study, the expected medical costs of the empirical and preemptive groups were 288,198 and 150,280 yen, respectively. Even in the case of the PREVERT study, in which the incidence of positive test results was 32.9 %, the expected medical costs in the empirical and preemptive groups were 291,871 and 284,944 yen, respectively. A sensitivity analysis indicated that the expected medical costs in the preemptive group would exceed those in the empirical group when the incidence of positive test results in the former was over 34.4 %. These results suggest that a preemptive treatment strategy can be expected to reduce medical costs compared with empirical therapy in most clinical settings. [ABSTRACT FROM AUTHOR]
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- 2015
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8. PAX3-NCOA2 fusion gene has a dual role in promoting the proliferation and inhibiting the myogenic differentiation of rhabdomyosarcoma cells.
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Yoshida, H, Miyachi, M, Sakamoto, K, Ouchi, K, Yagyu, S, Kikuchi, K, Kuwahara, Y, Tsuchiya, K, Imamura, T, Iehara, T, Kakazu, N, Hojo, H, and Hosoi, H
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STEROID receptor coactivators ,CELL proliferation ,MYOBLASTS ,CELL differentiation ,RHABDOMYOSARCOMA ,EMBRYONAL tumors ,CHROMOSOMAL rearrangement ,CHROMOSOMAL translocation ,GENETICS - Abstract
We analyzed a complex chromosomal translocation in a case of embryonal rhabdomyosarcoma (RMS) and showed that it generates the fusion gene PAX3 (paired box 3)-NCOA2 (nuclear receptor coactivator 2). To understand the role of this translocation in RMS tumorigenesis, we established two types of stable mouse myoblast C2C12 cell lines expressing PAX3-NCOA2 and PAX3-FOXO1A (forkhead box O1A), respectively. Compared with control cells, PAX3-NCOA2 cells grew faster, were more motile, were less anchorage dependent, progressed more quickly through the G1/S phase of cell cycle and showed greater transcriptional activation of the PAX3 consensus-binding site. However, PAX3-NCOA2 cells proliferated more slowly and differentiated more weakly than did PAX3-FOXO1A cells. Both PAX3-NCOA2 cells and PAX3-FOXO1A cells formed tumors in nude mice, although the PAX3-NCOA2-induced tumors grew more slowly. Our results may explain why NCOA2 rearrangement is mainly found in embryonal rhabdomyosarcoma, which has a better prognosis than alveolar rhabdomyosarcoma, which expresses the PAX3-FOXO1A fusion gene. These results indicate that the PAX3-NCOA2 fusion gene has a dual role in the tumorigenesis of RMS: promotion of the proliferation and inhibition of the myogenic differentiation of RMS cells. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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9. Load History Dependency of Plastic Collapse Behavior of Cracked Piping.
- Author
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Suzuki, R., Matsubara, M., Suzuki, M., Shiraishi, T., Yanagihara, S., Sakamoto, K., and Izawa, S.
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- 2013
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10. Mitsubishi Latest Coal Fired USC Boiler Technology (CFE Pacifico 700 MW).
- Author
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Hashimoto, T., Sakamoto, K., and Fujitab, M.
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- 2013
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11. Electrical time constants of erythrocytes for confocal and uniform thickness membrane.
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Scharfetter, Hermann, Merwa, Robert, Kanai, H., Furuya, N., Sakamoto, K., and Kanai, N.
- Abstract
The physical properties of tissues are of practical interest in medical engineering and various fields of medicine. In this study, the electrical time constants of living cells, especially erythrocytes, are discussed. β dispersion is often called as structural relaxation caused by cellular structure of tissues. The shape of cells, the membrane thickness of cells, the conductivity of intracellular fluid and the orientation of the cells affect the time constant of β dispersion. Therefore, we can get a lot of information such as intra- and extra-cellular volumes from β dispersion phenomenon. [1][2][3][4][8][11]. The electrical properties of blood can be analytically calculated by Fricke equation under some assumptions [9]. The most important assumption is that the shape of erythrocyte in blood approximated to the confocal ellipsoidal spheroid (shown in Fig.1). And all erythrocytes orient themselves so as to one of three -rectangular axis is parallel to the electrical field. This model has a single time constant, although the time constant of a real erythrocyte with constant membrane thickness must be distributed. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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12. Electrical Time Constant of Cell.
- Author
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Kim, Sun I., Suh, Tae Suk, Magjarevic, R., Nagel, J. H., Furuya, Norio, Kanai, H., Sakamoto, K., and Kanai, N.
- Abstract
The physical properties of tissues are of practical interest in medical engineering and various fields of medicine. In this study, the electrical time constants of living cells, especially erythrocytes, are discussed. β dispersion is often called as structural relaxation caused by cellular structure of tissues. The time constant of β dispersion is affected by the shape of cells, the membrane thickness of cells, the conductivity of intracellular fluid and the orientation of the cells. Therefore, we can get a lot of information such as intra- and extracellular volumes from β dispersion phenomenon. The electrical properties of blood can be analytically calculated by Fricke's equation under some assumptions. The most important assumption is that the shape of erythrocyte in blood approximated to the confocal ellipsoidal spheroid. This model has a single time constant, although the time constant of a real erythrocyte with constant membrane thickness must be distributed. As a result, the difference exists between the admittance locus analytically calculated from Fricke's model and the experimental results obtained from blood. In this study, comparison of the results analytically calculated by Fricke's equation and the results numerically calculated by boundary element method for the model with the constant membrane thickness were compared. From these results, the error of Fricke's results can be estimated. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
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13. Prediction of infectious complications by the combination of plasma procalcitonin level and localized infection before allogeneic hematopoietic cell transplantation.
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Sato, M, Nakasone, H, Terasako-Saito, K, Sakamoto, K, Yamazaki, R, Tanaka, Y, Akahoshi, Y, Nakano, H, Ugai, T, Wada, H, Yamasaki, R, Ishihara, Y, Kawamura, K, Ashizawa, M, Kimura, S-i, Kikuchi, M, Tanihara, A, Kanda, J, Kako, S, and Nishida, J
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COMPLICATIONS from organ transplantation ,COMMUNICABLE diseases ,GRAFT versus host disease ,HEMATOPOIETIC stem cell transplantation ,C-reactive protein - Abstract
We previously reported that the baseline C-reactive protein level did not predict infectious events after hematopoietic cell transplantation (HCT). Procalcitonin (PCT) has recently emerged as a powerful biomarker for the early diagnosis of bacterial infection. We evaluated the ability of the baseline PCT level to predict early infectious events after HCT in 79 recipients who received HCT between 2008 and 2012. The high-PCT group (0.07 ng/mL, n=27) frequently experienced documented infection (DI) (21.2% vs 44.4% at day 30, P=0.038) and bloodstream infection (BSI) (15.4% vs 37.0% at day 30, P=0.035). In a multivariate analysis, however, the baseline PCT level was not significantly associated with DI (HR 2.01, P=0.089) or BSI (HR 2.28, P=0.084). Localized infection, such as anal canal problems, before the start of conditioning was seen in 26 patients. When we stratified the patients according to the presence of elevated PCT and localized infection, the group with elevated PCT and localized infection (n=17) was significantly associated with increased DI (HR 3.40, P=0.0074) and BSI (HR 3.59 P=0.0078) after HCT. A larger prospective observation is warranted to confirm the impact of the baseline PCT level and clinical features on the outcome of HCT. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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14. Single-cell T-cell receptor-β analysis of HLA-A*2402-restricted CMV- pp65-specific cytotoxic T-cells in allogeneic hematopoietic SCT.
- Author
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Nakasone, H, Tanaka, Y, Yamazaki, R, Terasako, K, Sato, M, Sakamoto, K, Yamasaki, R, Wada, H, Ishihara, Y, Kawamura, K, Machishima, T, Ashizawa, M, Kimura, S-i, Kikuchi, M, Tanihara, A, Kanda, J, Kako, S, Nishida, J, and Kanda, Y
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T cell receptors ,HLA histocompatibility antigens ,HEMATOPOIETIC stem cell transplantation ,SINGLE cell proteins ,CELLULAR immunity - Abstract
Cellular immunity is important for the control of CMV infection after allogeneic hematopoietic cell transplantation (Allo-HCT). However, the actual in vivo dynamics of CMV-specific cytotoxic T cell (CMV-CTL) clones are still unclear. We conducted clone monitoring of tetramer
+ CMV-CTLs in HLA-A*2402-positive donor-patient pairs, using a direct single-cell analysis that enabled the simultaneous identification and quantification of CTL clones. Clone dynamics were assessed in three cases with or without CMV reactivation. In Case-1 without CMV reactivation, despite the long-term use of systemic steroid, dominant clones of Donor-1 persisted and remained dominant. The CMV-CTLs at 1 year after Allo-HCT included a high proportion of CD45RA+ CCR7− effector and CD27− CD57+ mature T cells. On the other hand, in Cases-2 and -3 with CMV reactivation, novel clones appeared and became dominant during the follow-up. Their CMV-CTLs included more CD27+ immature T cells at 1 year after Allo-HCT. With regard to clonotypes, HLA-A*2402-restricted CMV-CTLs tended to select BV7 and BJ1-1 genes for complementarity-determining region 3 (CDR3) of T-cell receptor (TCR)-β. Specific amino-acid sequences of CDR3 of TCR-β were found in each case. Patterns of clone reconstitution and phenotype would be different according to CMV reactivation. In vivo clone monitoring of CMV-CTLs could provide insight into the mechanism of immunological reconstitution following Allo-HCT. [ABSTRACT FROM AUTHOR]- Published
- 2014
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15. Prediction of transplant-related complications by C-reactive protein levels before hematopoietic SCT.
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Sato, M, Nakasone, H, Oshima, K, Ishihara, Y, Wada, H, Sakamoto, K, Kawamura, K, Ashizawa, M, Machishima, T, Terasako, K, Kimura, S, Kikuchi, M, Okuda, S, Tanihara, A, Yamazaki, R, Tanaka, Y, Kanda, J, Kako, S, Nishida, J, and Kanda, Y
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COMPLICATIONS from organ transplantation ,C-reactive protein ,HEMATOPOIETIC stem cell transplantation ,BIOMARKERS ,MORTALITY - Abstract
Various biomarkers have been investigated with regard to their ability to predict the outcome of allogeneic hematopoietic SCT (HSCT). In this study, we retrospectively reviewed 90 recipients who received HSCT between 2007 and 2011 in our institution, and evaluated the predictive value of the baseline serum C-reactive protein (CRP) levels just before the initiation of conditioning for transplant-related complications after allogeneic HSCT. A receiver-operating characteristic curve revealed that the baseline serum CRP levels had an excellent predictive value for non-relapse mortality (NRM), with an area under the curve of 0.83. The sensitivity and specificity for NRM were 80% and 87%, respectively, with a cutoff of 0.6 mg/dL. With this cutoff value, multivariate analyses revealed that a higher baseline CRP level was an independent risk factor for NRM (HR 6.21, P<0.01), grade III-IV acute GVHD (HR 3.91, P=0.03) and poor overall survival (HR 3.27, P=0.0018). On the other hand, the baseline CRP level did not predict infectious events. These findings suggested that CRP levels before conditioning may be a useful predictive biomarker for poor survival. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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16. Promotion of DNA repair by nuclear IKKβ phosphorylation of ATM in response to genotoxic stimuli.
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Sakamoto, K, Hikiba, Y, Nakagawa, H, Hirata, Y, Hayakawa, Y, Kinoshita, H, Nakata, W, Sakitani, K, Takahashi, R, Akanuma, M, Kamata, H, and Maeda, S
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ATAXIA telangiectasia , *DNA damage , *PHOSPHORYLATION , *APOPTOSIS , *DNA repair , *GENETICS - Abstract
Ataxia-telangiectasia mutated (ATM) is one of the key molecules involved in the cellular response to DNA damage. A portion of activated ATM is exported from the nucleus into the cytoplasm, where it activates the I kappa B kinase/nuclear factor kappa B (IKK/NF-κB) signaling pathway. It has been thought that activated IKKβ, which is a critical kinase for NF-κB activation, generally resides in the cytoplasm and phosphorylates cytoplasmic downstream molecules, such as IκBα. Here, we identified a new role for IKKβ during the response to DNA damage. ATM phosphorylation in response to alkylating agents consisted of two phases: the early phase (up to 3 h) and late phase (after 6 h). A portion of the activated IKKβ generated during the DNA damage response was found to translocate into the nucleus and directly phosphorylate ATM in the late phase. Furthermore, the phosphorylation of ATM by nuclear IKKβ was suggested to promote DNA repair. In parallel, activated IKKβ induced classical NF-κB activation and was involved in anti-apoptosis. Our findings define the function of IKKβ during the response to DNA damage, which promotes cell survival and DNA repair, and maintains cellular homeostasis. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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17. Hyperbilirubinemia in the early phase after allogeneic HSCT: prognostic significance of the alkaline phosphatase/total bilirubin ratio.
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Ashizawa, M, Oshima, K, Wada, H, Ishihara, Y, Kawamura, K, Sakamoto, K, Sato, M, Terasako, K, Machishima, T, Kimura, S, Kikuchi, M, Nakasone, H, Okuda, S, Kako, S, Kanda, J, Yamazaki, R, Tanihara, A, Nishida, J, and Kanda, Y
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HYPERBILIRUBINEMIA ,SINUSOIDAL projection (Cartography) ,ALKALINE phosphatase ,BILIRUBIN ,SPECTRUM analysis ,BLOOD plasma - Abstract
Hyperbilirubinemia in the early phase after allogeneic hematopoietic SCT (HSCT) is due to various causes. One of the most important causes of hyperbilirubinemia is veno-occlusive disease/sinusoidal obstructive syndrome (VOD/SOS). However, the prognosis of patients who are clinically diagnosed as SOS varies. We retrospectively evaluated 82 patients who underwent their first allogeneic HSCT. GVHD prophylaxis was a combination of short-term MTX and CsA (n=77) or tacrolimus (n=5). Thirty-three patients developed hyperbilirubinemia, with a bilirubin level of at least 2 mg/dL, within 20 days after HSCT. Of these patients, 24 were diagnosed as VOD/SOS using the modified Seattle criteria. Twenty-six recovered to a bilirubin level of <2 mg/dL. We focused on the serum alkaline phosphatase/total bilirubin ratio (ALP/TB) at the onset of hyperbilirubinemia and found that it significantly predicted the recovery from hyperbilirubinemia. OS was significantly higher in patients with a lower ALP/TB ratio (P=0.00056). In addition, a lower ALP/TB ratio was associated with better survival even in patients who were clinically diagnosed as SOS (P<0.001). The ALP/TB ratio at the onset of hyperbilirubinemia may be a useful predictor for the prognosis of hyperbilirubinemia and SOS early after HSCT. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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18. TGF-β drives epithelial-mesenchymal transition through δEF1-mediated downregulation of ESRP.
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Horiguchi, K, Sakamoto, K, Koinuma, D, Semba, K, Inoue, A, Inoue, S, Fujii, H, Yamaguchi, A, Miyazawa, K, Miyazono, K, and Saitoh, M
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TRANSFORMING growth factors-beta , *EPITHELIUM , *MESENCHYMAL stem cells , *ELONGATION factors (Biochemistry) , *CANCER invasiveness , *CELL lines , *BREAST cancer , *FIBROBLAST growth factors - Abstract
Epithelial-mesenchymal transition (EMT) is a crucial event in wound healing, tissue repair and cancer progression in adult tissues. We have recently shown that transforming growth factor (TGF)-β-induced EMT involves isoform switching of fibroblast growth factor receptors by alternative splicing. We performed a microarray-based analysis at single exon level to elucidate changes in splicing variants generated during TGF-β-induced EMT, and found that TGF-β induces broad alteration of splicing patterns by downregulating epithelial splicing regulatory proteins (ESRPs). This was achieved by TGF-β-mediated upregulation of δEF1 family proteins, δEF1 and SIP1. δEF1 and SIP1 each remarkably repressed ESRP2 transcription through binding to the ESRP2 promoter in NMuMG cells. Silencing of both δEF1 and SIP1, but not either alone, abolished the TGF-β-induced ESRP repression. The expression profiles of ESRPs were inversely related to those of δEF1 and SIP in human breast cancer cell lines and primary tumor specimens. Further, overexpression of ESRPs in TGF-β-treated cells resulted in restoration of the epithelial splicing profiles as well as attenuation of certain phenotypes of EMT. Therefore, δEF1 family proteins repress the expression of ESRPs to regulate alternative splicing during TGF-β-induced EMT and the progression of breast cancers. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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19. Improved Herbert Hardness Tester.
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Matsubara, M. and Sakamoto, K.
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HARDNESS testing , *DAMPING (Mechanics) , *PENDULUMS , *DEFORMATIONS (Mechanics) , *VISCOELASTIC materials - Abstract
Herbert hardness tester is a typical pendulum hardness tester. In this work, the tester is improved based on the model modified by Habara et al. The improved tester makes it possible to measure the swing motion of the tester electrically. The new hardness 'Damping hardness' is derived form the damping factor of a swing angle-time curve observed. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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20. Release behavior of small sized daughter allergens from Cryptomeria japonica pollen grains during urban rainfall event.
- Author
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Wang, Q., Nakamura, S., Lu, S., Xiu, G., Nakajima, D., Suzuki, M., Sakamoto, K., and Miwa, M.
- Abstract
In Japan, Cryptomeria japonica pollen (with diameter ~30 μm) is scattered during each spring season. Daughter allergenic particles, which are smaller in size than their parent pollen grain and are abundant in fine particles (the particle sizes < 1.1 μm, PM), are released in the atmosphere. The daughter allergenic particles of pollen can be transported in the urban atmosphere for a long period of time after their release. In particular, the daily variation delays in the peaks of allergenic Cry j 1 concentrations compared with the peaks of airborne parent pollen counts were observed in high levels during 1 or 2 sunny days after rainfall. In addition, long range transportation of Asian dusts (ADS) from the East Asian continent was also found during the pollen scattering seasons in Japan. Therefore, the interaction between pollen and air pollutants, including ADS, should be of concern. Thus, in this study, the morphological change of Cryptomeria japonica pollen and the elution behavior of its allergenic contents (Cry j 1) were investigated. Our results confirmed the existence of fine daughter allergen particles, which are clearly differ from the parent pollen grains in size. Fine allergenic particles in atmosphere were increased, while coarse allergenic particles were decreased on sunny days after rainfall. However, the correlation between the mass concentrations of fine particles and mass levels of Cry j 1 in coarse particles (the particle sizes > 7.0 μm) was poor. The possible reason may be pollen burst at high humidity before rainfall. Additionally, Cry j 1 contents were emitted from the so-called Ubisch body, which contains allergenic Cry j 1 abundantly when pollen was in contact with rainfall. In particular, we found that 60% of allergenic Cry j 1 contents released in air polluted rainfall contained Ca ion derived from road dust and ADS. Therefore, rainfall should be a main factor to induce transition of pollen allergenic contents to fine particles. In conclusion, allergenic particles which are small sized and translated into fine particles by rainfall can be inhaled into the lower respiratory tract and contribute to the hypersensitivity of asthma. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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21. Cardiovascular responses to arm static exercise in men with thoracic spinal cord lesions.
- Author
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Sakamoto K, Nakamura T, Umemoto Y, Koike Y, Sasaki Y, Tajima F, Sakamoto, Keiko, Nakamura, Takeshi, Umemoto, Yasunori, Koike, Yumi, Sasaki, Yusuke, and Tajima, Fumihiro
- Abstract
Isometric muscle contraction (static exercise) induces circulatory response. Static exercise in individuals with thoracic spinal cord injury (TSCI) induces cardiovascular response and blood redistribution to the non-exercising muscles. The aim of our study was to determine the circulatory response during arm static exercise in individuals with TSCI and able-bodied (AB) controls. Mean blood pressure (MBP), heart rate (HR), cardiac output (CO), leg skin blood flow (SBF), and leg muscle blood flow (MBF) were recorded noninvasively, total peripheral resistance (TPR) was estimated by dividing MBP by CO, and hormonal changes were measured before, during and after static 35% maximal voluntary contraction (MVC) of the arm flexor muscles in seven male individuals with TSCI (T7-T11) and seven age-comparable AB control (32.2 ± 7.6 and 31.0 ± 4.7 years, respectively). The 35% MVC was similar in TSCI and AB individuals (107.3 ± 28.2 and 101.0 ± 22.5 N, respectively). HR, CO, MBP, TPR, SBF and MBF increased in both groups during arm static exercise. Plasma epinephrine concentration increased during arm static exercise in AB controls only (P < 0.05). Circulation to leg muscles was similar in TSCI and AB individuals and the lack of sympathetic vasoconstriction in the paralyzed leg area did not alter the cardiovascular responses during 35% MVC of arm static exercise. We conclude that sympathetic vasoconstriction in the resting leg area did not contribute to the pressor reflex during 35% MVC of arm static exercise. [ABSTRACT FROM AUTHOR]
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- 2012
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22. Prostate atypia: clinical and pathological variables associated with cancer diagnosis on repeat biopsy.
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Kopp, R. P., Parsons, J. K., Shiau, J., Wang-Rodriguez, J., Palazzi-Churas, K., Silberstein, J. L., Derweesh, I. H., and Sakamoto, K.
- Subjects
DIAGNOSIS ,PROSTATE cancer ,BIOPSY ,TUMORS ,CLINICAL pathology ,LYMPH nodes - Abstract
The clinical significance of atypical glands suspicious for malignancy (atypia) on prostate biopsy is unclear. We studied a cohort of 139 patients with atypia who underwent repeat prostate biopsy. We analyzed clinical and pathological variables that may be associated with cancer on repeat biopsy. Cancer was diagnosed in 41 (29%) of patients with atypia: 26 of 41 (66%) were Gleason 6, 20% were Gleason 7 and 7% were Gleason 8 (Gleason <6 not reported). There were no significant associations of age, race, family history, PSA, PSA density (PSAd), number of previous biopsies or time to repeat biopsy with cancer diagnosis. In multivariate regression, histological inflammation was associated with an 85% decreased probability of cancer on repeat biopsy (odds ratio; OR 0.15; 95% confidence interval; CI 0.04-0.57; P=0.04). Radical prostatectomy was performed in 14 of 41 (34%) patients with cancer; 6 (43%) were Gleason sum 7, 3 (21%) were pT3a and 1 (7%) had lymph node metastases. In conclusion, inflammation was independently associated with a significantly decreased risk of cancer on repeat biopsy. However, some patients with initial atypia have higher-risk prostate cancer. Additional studies are needed to elucidate these associations. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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- View/download PDF
23. Robot-assisted laparoscopic radical prostatectomy in men with human immunodeficiency virus.
- Author
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Silberstein, J. L., Parsons, J. K., Palazzi-Churas, K., Downs, T. M., Sakamoto, K, Derweesh, I. H., Woldrich, J., and Kane, C. J.
- Subjects
HIV ,AIDS ,PROSTATECTOMY ,HIGHLY active antiretroviral therapy ,COMBINATION drug therapy - Abstract
The aim of this study is to evaluate the outcomes of robot-assisted laparoscopic prostatectomy (RALP) in prostate cancer (PCa) patients with human immunodeficiency virus (HIV). This is a prospective cohort study of HIV patients undergoing RALP, comparing the demographics, tumor characteristics, complications, and short-term oncological outcomes of HIV-positive men to HIV-negative men using univariate (χ
2 , Mann-Whitney test) and multivariable (logistic regression) analyses. From 2007 to 2010, 298 men underwent RALP, 8 of whom were known to be HIV positive. Preoperatively, all eight were taking highly active antiretroviral therapy (HAART) and had undetectable viral loads (<50); mean CD4 count was 634 cells per mm3 . HIV-positive men were younger (54 versus 62 years, P=0.010) and less likely to be white (P=0.007). There were no significant differences between groups with respect to clinical staging, pathological and oncological outcomes or most complication rates. However, the prevalence of perioperative transfusions (P=0.031) and ileus (P=0.021) were higher in HIV-positive patients. HIV remained significantly associated with risk of transfusion after adjustment for age, race, Gleason sum and clinical T stage (P=0.002). After a median of 2.6 (range 0.03-19.2) months of follow-up, PSA remained undetectable in all eight HIV patients. These data suggest that RALP is safe for, and demonstrates short-term oncological efficacy in, HIV-positive patients with PCa. [ABSTRACT FROM AUTHOR]- Published
- 2010
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24. Janus kinase 2 is required for the initiation but not maintenance of prolactin-induced mammary cancer.
- Author
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Sakamoto, K, Triplett, A A, Schuler, L A, and Wagner, K-U
- Subjects
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PROTEIN-tyrosine kinases , *PROLACTIN , *MAMMARY glands , *BREAST tumors , *CELL receptors , *CELLULAR signal transduction , *GROWTH factors , *TRANSGENIC mice - Abstract
The prolactin receptor (PRLR), its associated Janus kinase 2 (Jak2) and the signal transducer and activator of transcription 5 (Stat5) are essential for normal mammary gland development. Owing to the upregulation of the PRLR and the local synthesis of its ligand in neoplastic cells, it has been proposed that PRL can act as a local growth factor in human breast cancers. This notion is supported by experimental evidence in transgenic mice, which showed that the mammary-specific expression of PRL contributes to carcinogenesis in vivo. To assess the importance of Jak2/Stat5 signaling during mammary cancer initiation and progression, we generated a PRL-induced mammary cancer model that allows the functional ablation of the Jak2 gene in the mammary epithelium before and after neoplastic transformation. Collectively, the results of this study show that the functional ablation of Jak2 protects against the onset of PRL-induced mammary tumorigenesis, suggesting that targeting this kinase is a relevant strategy for mammary cancer prevention. Surprisingly, Jak2 deficiency did not affect the growth and survival of PRL-induced mammary cancer cells in culture and in vivo. Consequently, Jak2 cannot be a sole therapeutic target to treat the established disease. PRL-induced mammary cancers exhibited an upregulation of ErbB2 and other ErbB receptor tyrosine kinases that may supersede the functionality of PRLR signaling through Jak2. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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- View/download PDF
25. Pseudolesion of the liver observed on gadoxetate disodium-enhanced magnetic resonance imaging obtained shortly after transarterial chemoembolization for hepatocellular carcinoma.
- Author
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Shinagawa Y, Sakamoto K, Fujimitsu R, Ida M, Urakawa H, Kora S, Higashihara H, Takano K, Yoshimitsu K, Shinagawa, Yoshinobu, Sakamoto, Keiko, Fujimitsu, Ritsuko, Ida, Mikiko, Urakawa, Hiroshi, Kora, Shin-Ichi, Higashihara, Hideyuki, Takano, Kouichi, and Yoshimitsu, Kengo
- Abstract
The purpose of this report was to describe pseudolesions of the liver that mimicked residual hypervascular hepatocellular carcinoma (HCC), as observed on gadoxetate disodium-enhanced magnetic resonance imaging (EOB-MRI) obtained shortly after transarterial chemoembolization (TACE). Between June 2008 and December 2008, three patients underwent MRI within 12 days after TACE to rule out remaining viable cancerous tissue or to assess the treatment effect. In all three patients, nontumorous liver tissue adjacent to the treated HCC exhibited focal arterial enhancement on dynamic phase and subsequent diminished uptake of gadoxetate disodium on hepatocellular phase images, which mimicked residual HCC. All three patients had mild postembolization syndrome at the time of EOB-MRI and showed no evidence of residual or recurrent tumors on follow-up. The findings of these areas may represent transient focal hyperemia and damage to the liver cell function caused by TACE. Radiologists should be aware that EOB-MRI obtained shortly after TACE may show pseudolesions around the treated tumors and should not mistake them for residual or recurrent tumors. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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26. Effectiveness of IkappaB kinase inhibitors in murine colitis-associated tumorigenesis.
- Author
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Hayakawa Y, Maeda S, Nakagawa H, Hikiba Y, Shibata W, Sakamoto K, Yanai A, Hirata Y, Ogura K, Muto S, Itai A, Omata M, Hayakawa, Yoku, Maeda, Shin, Nakagawa, Hayato, Hikiba, Yohko, Shibata, Wataru, Sakamoto, Kei, Yanai, Ayako, and Hirata, Yoshihiro
- Abstract
Purpose: Nuclear factor kappaB (NF-kappaB) activation is involved in various inflammatory illnesses, for example inflammatory bowel disease, and is thought to be a key factor in the tumor-promoting mechanism of inflammation-associated tumorigenesis. This study investigated whether inhibitors of IKKbeta, which is a critical kinase for NF-kappaB activation, reduce colitis-associated tumorigenesis in mice.Methods: We used a mouse model of the disease whereby administration of azoxymethane (AOM) followed by repeated dextran sulfate sodium (DSS) ingestion causes severe colonic inflammation and the subsequent development of multiple tumors. Effects of IKKbeta inhibitors, NBD peptide, and IMD-0354 were examined.Results: In a colitis-associated cancer model, treatment with the IKKbeta inhibitors NBD peptide and IMD-0354 significantly reduced the number of tumors compared with the untreated group. The tumors were also significantly smaller in the inhibitor-treated mice than in the untreated mice. Macrophage and neutrophil infiltration decreased with the inhibitor treatment. NF-kappaB activation and the expression of Cox-2 and iNOS were observed in tumor tissues, and the inhibitors ameliorated their expression. These inhibitors blocked NF-kappaB activation and the expression of proinflammatory cytokines mediated by the culture supernatant of inflamed colon in murine primary macrophages. In-vitro and in-vivo experiments showed that these drugs, especially NBD peptide, could also inhibit the proliferation of colonic epithelial cells.Conclusion: These results imply that IKKbeta-targeted NF-kappaB blockade is an attractive therapeutic approach for the prevention of colitis-associated tumors. [ABSTRACT FROM AUTHOR]- Published
- 2009
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27. Targeting steroid hormone receptors for ubiquitination and degradation in breast and prostate cancer.
- Author
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Rodriguez-Gonzalez, A., Cyrus, K., Salcius, M., Kim, K., Crews, C. M., Deshaies, R. J., and Sakamoto, K. M.
- Subjects
PROTEOLYSIS ,EUKARYOTIC cells ,PEPTIDES ,CANCER cells ,RETINOBLASTOMA ,PHOSPHORYLATION ,UBIQUITIN ,GENITAL cancer ,CANCER treatment - Abstract
Proteolysis targeting chimeric molecules (Protacs) target proteins for destruction by exploiting the ubiquitin-dependent proteolytic system of eukaryotic cells. We designed two Protacs that contain the peptide ‘degron’ from hypoxia-inducible factor-1α, which binds to the Von –Hippel–Lindau (VHL) E3 ubiquitin ligase complex, linked to either dihydroxytestosterone that targets the androgen receptor (AR; Protac-A), or linked to estradiol (E2) that targets the estrogen receptor-α (ERα; Protac-B). We hypothesized that these Protacs would recruit hormone receptors to the VHL E3 ligase complex, resulting in the degradation of receptors, and decreased proliferation of hormone-dependent cell lines. Treatment of estrogen-dependent breast cancer cells with Protac-B induced the degradation of ERα in a proteasome-dependent manner. Protac-B inhibited the proliferation of ERα-dependent breast cancer cells by inducing G
1 arrest, inhibition of retinoblastoma phosphorylation and decreasing expression of cyclin D1, progesterone receptors A and B. Protac-B treatment did not affect the proliferation of estrogen-independent breast cancer cells that lacked ERα expression. Similarly, Protac-A treatment of androgen-dependent prostate cancer cells induced G1 arrest but did not affect cells that do not express AR. Our results suggest that Protacs specifically inhibit the proliferation of hormone-dependent breast and prostate cancer cells through degradation of the ERα and AR, respectively.Oncogene (2008) 27, 7201–7211; doi:10.1038/onc.2008.320; published online 15 September 2008 [ABSTRACT FROM AUTHOR]- Published
- 2008
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28. Cloning and expression of the l-1-amino-2-propanol dehydrogenase gene from Rhodococcus erythropolis, and its application to double chiral compound production.
- Author
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Kataoka, M., Ishige, T., Urano, N., Nakamura, Y., Sakuradani, E., Fukui, S., Kita, S., Sakamoto, K., and Shimizu, S.
- Subjects
PROPANOLS ,DEHYDROGENASES ,AMINO acids ,ESCHERICHIA coli ,AMINO acid sequence ,GENETIC vectors ,CATALYSIS ,ENZYMES ,EPHEDRINE - Abstract
The gene encoding NADP
+ -dependent l-1-amino-2-propanol dehydrogenase (AADH) of Rhodococcus erythropolis MAK154 was cloned and sequenced. A 780-bp nucleotide fragment was confirmed to be the gene encoding AADH by agreement of the N-terminal and internal amino acid sequences of the purified AADH. The gene ( aadh) codes a total of 259 amino acid residues, and the deduced amino acid sequence shows similarity to several short-chain dehydrogenase/reductase family proteins. An expression vector, pKKAADH, which contains the full length aadh was constructed. Escherichia coli cells possessing pKKAADH exhibited a 10.4-fold increase in specific activity as to catalysis of the reduction of ( S)-1-phenyl-2-methylaminopropan-1-one (MAK), as compared with that of R. erythropolis MAK154 induced by 1-amino-2-propanol (1 mg/ml). Coexpression of aadh with a cofactor regeneration enzyme (glucose dehydrogenase) gene was also performed, and a system for sufficient production of d-pseudoephedrine from racemic MAK was constructed. [ABSTRACT FROM AUTHOR]- Published
- 2008
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29. Circulating cell-free DNA as a predictive marker for distant metastasis of hepatitis C virus-related hepatocellular carcinoma.
- Author
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Tokuhisa, Y., Iizuka, N., Sakaida, I., Moribe, T., Fujita, N., Miura, T., Tamatsukuri, S., Ishitsuka, H., Uchida, K., Terai, S., Sakamoto, K., Tamesa, T., and Oka, M.
- Subjects
HEPATITIS C virus ,HEPATITIS C ,CANCER prognosis ,HEPATECTOMY ,SERUM ,SURVIVAL ,DNA ,LIVER tumors ,PREDICTIVE tests ,HEPATITIS viruses ,DISEASE relapse ,HEPATOCELLULAR carcinoma ,PROPORTIONAL hazards models ,LONGITUDINAL method ,DISEASE complications - Abstract
In a previous study, we showed that levels of cell-free DNA (cfDNA) were significantly higher in sera of patients with hepatocellular carcinoma (HCC) associated with hepatitis C virus (HCV) than in sera of non-HCC patients with HCV. To confirm this finding, we analysed serum cfDNA levels in a cohort of 96 patients with HCV-related HCC and in 100 HCV carriers without known HCC. Again we found that serum cfDNA levels were significantly higher in HCC patients than in HCV carriers (115.9+/-98.3 vs 34.4+/-40.4 ng ml(-1) (mean+/-s.d.), P<0.0001). Of 87 eligible patients who underwent curative hepatectomy, those with a high cfDNA level had a significantly shorter overall survival (OS) time than those in whom the cfDNA level was not high. Cox proportional hazards model showed the cfDNA level to be an independent prognostic factor for OS and cancer recurrence in distant organs. Our results suggest that the serum cfDNA level reflects the metastatic potential of HCV-related HCC and that it can be a useful predictive biomarker for distant metastasis after curative surgery. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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30. Antigenic properties of porcine teschovirus 1 (PTV-1) Talfan strain and molecular strategy for serotyping of PTVs.
- Author
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Kaku, Y., Murakami, Y., Sarai, A., Wang, Y., Ohashi, S., and Sakamoto, K.
- Subjects
TESCHEN disease virus ,TESCHEN disease ,VIRUSES ,ANTIGENS ,IMMUNITY ,PHYLOGENY - Abstract
For reliable diagnosis of porcine teschovirus (PTV) infection we created an RT-PCR-based molecular strategy for serotyping that encompassed the dominant neutralizing antigenic site of PTV, followed by phylogenetic analyses of amplicons. We identified neutralizing antigenic sites of PTV-1 Talfan strain through epitope mapping of neutralizing monoclonal antibodies (MAbs), using synthetic peptides spanning the capsid proteins. All 11 MAbs obtained recognized peptides in the EF loop (“puff”) of VP2 protein. Two MAbs concurrently reacted to peptides, one in the GH loop of VP1 and one in the VP1 C terminus. Three-dimensional modeling of Talfan capsid protein predicted exposure of all these sites on the virion surface in a close line centered around puff. We then designed a single pair of degenerate primers to VP2 and amplified the region of ∼320 bp encompassing puff in 8 PTV prototype strains and 6 field isolates. Phylogenetic analyses of the puff sequences of 11 prototype strains and 34 field isolates obtained from databanks showed that all homotypic strains (both field and prototype) were always monophyletic, except for one ‘untypable’ Japanese strain. This RT-PCR-based strategy appears to be a reliable surrogate for serotyping and could facilitate the diagnosis and epidemiological study of PTV infection. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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- View/download PDF
31. Mapping and characterization of FLC homologs and QTL analysis of flowering time in Brassica oleracea.
- Author
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Okazaki, K., Sakamoto, K., Kikuchi, R., Saito, A., Togashi, E., Kuginuki, Y., Matsumoto, S., and Hirai, M.
- Subjects
- *
COLE crops , *ARABIDOPSIS , *HOMOLOGY (Biology) , *FLOWERING time , *GENETICS - Abstract
The FLC gene product is an inhibitor of flowering in Arabidopsis. FLC homologs in Brassica species are thought to control vernalization. We cloned four FLC homologs ( BoFLCs) from Brassica oleracea. Three of these, BoFLC1, BoFLC3 and BoFLC5, have been previously characterized. The fourth novel sequence displayed 98% sequence homology to the previously identified gene BoFLC4, but also showed 91% homology to BrFLC2 from Brassica rapa. Phylogenetic analysis showed that this clone belongs to the FLC2 clade. Therefore, we designated this gene BoFLC2. Based on the segregation of RFLP, SRAP, CAPS, SSR and AFLP loci, a detailed linkage map of B. oleracea was constructed in the F2 progeny obtained from a cross of B. oleracea cv. Green Comet (broccoli; non-vernalization type) and B. oleracea cv. Reiho (cabbage; vernalization type), which covered 540 cM, 9 major linkage groups. Six quantitative trait loci (QTL) controlling flowering time were detected. BoFLC1, BoFLC3 and BoFLC5 were not linked to the QTLs controlling flowering time. However, the largest QTL effect was located in the region where BoFLC2 was mapped. Genotyping of F2 plants at the BoFLC2 locus showed that most of the early flowering plants were homozygotes of BoFLC-GC, whereas most of the late- and non-flowering plants were homozygotes of BoFLC-Rei. The BoFLC2 homologs present in plants of the non-vernalization type were non-functional, due to a frameshift in exon 4. Moreover, duplications and deletions of BoFLC2 were detected in broccoli and a rapid cycling line, respectively. These results suggest that BoFLC2 contributes to the control of flowering time in B. oleracea. [ABSTRACT FROM AUTHOR]
- Published
- 2007
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- View/download PDF
32. Association of soluble CD40 ligand with carotid atherosclerosis in Japanese type 1 diabetic patients.
- Author
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Katakami, N., Kaneto, H., Matsuhisa, M., Miyatsuka, T., Sakamoto, K., Kawamori, D., Yoshiuchi, K., Nakamura, Y., Kato, K., Yamamoto, K., Kosugi, K., Hori, M., and Yamasaki, Y.
- Subjects
ATHEROSCLEROSIS ,DIABETES ,CAROTID artery ,PEOPLE with diabetes ,BLOOD plasma ,SERUM - Abstract
Aims/hypothesis: It has recently been shown that the soluble form of CD40 ligand (sCD40L) interacts with CD40 on vascular cells, leading to a variety of proinflammatory responses, and that serum sCD40L levels can be a predictive marker of cardiovascular events. The aim of this study was to estimate sCD40L levels in type 1 diabetic patients to examine a possible association with carotid atherosclerosis. Subjects and methods: Human sCD40L levels in serum and intima-media thickness (IMT) of carotid artery were examined in 80 Japanese type 1 diabetic patients (27 men and 53 women, age 22.8± 3.4 years (mean±SD), duration of diabetes 13.2±6.1 years) and 20 healthy age-matched non-diabetic individuals. Results: Serum sCD40L levels were significantly (p=0.0185) higher in subjects with type 1 diabetes (2.10± 1.33 ng/ml) compared with non-diabetic subjects (1.35± 0.88 ng/ml). The greatest IMT (Max-IMT) and averaged IMT (Mean-IMT) were also significantly greater in patients with type 1 diabetes than in control subjects (0.73±0.14 vs 0.64±0.07 mm, p=0.0041, 0.63±0.09 vs 0.57±0.06 mm, p=0.0066, respectively). Levels of sCD40L were statistically significantly associated with Max-IMT (r=0.383, p<0.001) and Mean-IMT (r=0.275, p=0.0058). Furthermore, stepwise multivariate regression analyses demonstrated that sCD40L is a determinant of both Max- and Mean-IMT, independently of conventional risk factors. Conclusions/interpretation: It is suggested that increased levels of serum sCD40L are associated with accelerated atherosclerotic change observed in young patients with type 1 diabetes. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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33. THE DESIGNS OF HIGH EFFICIENCY LAUNCHER OF QUASI-OPTICAL MODE CONVERTER FOR HIGH POWER GYROTRONS.
- Author
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Minami, R., Kasugai, A., Takahashi, K., Kobayashi, N., Mitsunaka, Y., and Sakamoto, K.
- Abstract
A high efficiency launcher of quasi-optical (QO) mode converters for high power gyrotrons have been designed and tested. A helical cut launcher radiates the RF power via its straight cut onto the first phase correcting mirror. The launchers have been optimized for the TE
31.8 mode at 170 GHz and TE22.6 mode at 110 GHz by numerically optimizing a launcher surface. The helical cut of the launcher has been optimized by taking the taper angle into account. Further more, the amplitude of the surface perturbation have been optimized for improved focusing in order to reduce the diffraction losses at the helical cut. Low power measurement shows a good agreement with the design. High efficiency characteristics of the design have also been calculated on the assumption of frequency downshift due to the thermal expansion of the cavity and stepwise frequency tuning by changing the operating mode. Besides, the possibility of high efficiency launcher for higher mode is discussed, and these results give the prospect to high efficiency long pulse gyrotrons. [ABSTRACT FROM AUTHOR]- Published
- 2006
- Full Text
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34. Comparison of stent placement and colostomy as palliative treatment for inoperable malignant colorectal obstruction.
- Author
-
Tomiki, Y., Watanabe, T., Ishibiki, Y., Tanaka, M., Suda, S., Yamamoto, T., Sakamoto, K., and Kamano, T.
- Subjects
PALLIATIVE treatment ,THERAPEUTICS ,CLINICAL medicine ,COLON surgery ,COLOSTOMY ,COLECTOMY - Abstract
Background: Stent placement is a useful palliative treatment for inoperable acute malignant colorectal obstruction. However, data comparing stent placement with colostomy are scarce. Methods: We compared the clinical outcome of 18 patients who had stent placement and 17 patients who underwent only colostomy. Results: The postoperative hospital stay was 22.3 days for stent placement compared with 47.4 days for colostomy (p = 0.016). The duration to readmission was 129.2 days for stent placement and 188.4 days for colostomy. The estimated duration of primary stent patency was 106 days. Mean survival period was 134 days in patients with stem placement and 191 days in patients with colostomy. Conclusion: Postoperative hospital stay was shorter in patients with stent placement but duration to readmission and survival were longer in patients with colostomy. However, stent placement increases the option of palliative treatment and is an effective treatment contributing to improving quality of life. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
35. Electrical admittance method for estimating fluid removal during artificial dialysis.
- Author
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Sakamoto, K., Kanai, H., and Furuya, N.
- Subjects
- *
DIALYSIS (Chemistry) , *EXTRACELLULAR fluid , *BIOELECTRIC impedance , *IMPEDANCE spectroscopy , *BODY fluids , *FILTERS & filtration , *BIOLOGICAL models , *COMPARATIVE studies , *HEMODIALYSIS , *RESEARCH methodology , *MEDICAL cooperation , *RESEARCH , *EVALUATION research , *PHENOMENOLOGICAL biology - Abstract
Because the conductivity of blood changes remarkably during artificial dialysis, sometimes by more than 20%, changes in tissue admittance at low frequency are caused by changes not only in the extracellular fluid volume but also in blood conductivity. Therefore the changes in blood conductance due to artificial dialysis must be considered for the estimation of water removal by the admittance method. An accurate bio-impedance measurement system was developed. Measurement error was less than 1% at low frequency and 10% at high frequency. A new electrical bio-admittance method (NAM) was evaluated for the continuous measurement of removed fluid volume, using a three parallel-compartment tissue model, consisting of intracellular, interstitial and blood compartments, which takes into account the blood conductivity change. NAM used the equivalent conductivity calculated from the leg admittances of patients, measured at 1 min intervals during various artificial dialysis procedures. The actual amount of excess water removed by ultra-filtration agreed with the NAM-estimated amount within an error of 20%. NAM was also applied to estimate the intra- and extracellular fluid changes. The results were consistent with the physiological changes known to occur during the various forms of dialysis. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
36. Distribution of similar self-incompatibility (S) haplotypes in different genera, Raphanus and Brassica.
- Author
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Okamoto, S., Sato, Y., Sakamoto, K., and Nishio, T.
- Subjects
RADISHES ,BRASSICA ,BRASSICACEAE ,PLANT genetics - Abstract
The nucleotide sequences of ten SP11 and nine SRK alleles in Raphanus sativus were determined, and deduced amino acid sequences were compared with those of Brassica SP11 and SRK. The amino acid sequence identity of class-I SP11s in R. sativus was about 30% on average, the highest being 52.2%, while that of the S domain of class-I SRK was 77.0% on average and ranged from 70.8% to 83.9%. These values were comparable to those of SP11 and SRK in Brassica oleracea and B. rapa. SP11 of R. sativus S-21 was found to be highly similar to SP11 of B. rapa S-9 (89.5% amino acid identity), and SRK of R. sativus S-21 was similar to SRK of B. rapa S-9 (91.0%). SP11 and SRK of R. sativus S-19 were also similar to SP11 and SRK of B. oleracea S-20, respectively. These similarities of both SP11 and SRK alleles between R. sativus and Brassica suggest that these S haplotype pairs originated from the same ancestral S haplotypes. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
37. Formation of intermetallic compound layers in Sn/Au/Sn diffusion couple during annealing at 433 K.
- Author
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Yamada, T., Miura, K., Kajihara, M., Kurokawa, N., and Sakamoto, K.
- Subjects
GOLD ,TIN ,METALLOGRAPHY ,ANNEALING of metals ,INTERMETALLIC compounds ,KIRKENDALL effect - Abstract
The kinetics of the reactive diffusion between Au and Sn was experimentally studied in a metallographical manner. Sn/Au/Sn diffusion couples were prepared by a solid-state diffusion bonding technique and then annealed at 433 K for various times between 1 and 127 h (3.6 × 10³ and 4.57 × 10
5 s) in an oil bath with silicone oil. Due to annealing, intermetallic compound layers consisting of AuSn4 , AuSn2 and AuSn are produced at the Au/Sn interface in the diffusion couple. The thickness of the AuSn4 layer is four times greater than those of the AuSn2 and AuSn layers. The ratio of the thicknesses of the compound layers remains constant during annealing. The total thickness I of the compound layers increases with annealing time t. Such a relationship is mathematically described by the equation I = k(t/t0 )n , where t0 is unity time, 1 s. From the experimental results, the proportionality coefficient and the exponent are determined to be k = 2.7 × 10-7 m and n = 0.42, respectively, by a least-squares method. The exponent n is slightly smaller than 0.5. This implies that the grain boundary diffusion partially contributes to the rate-controlling process for the growth of the compound layers. [ABSTRACT FROM AUTHOR]- Published
- 2004
- Full Text
- View/download PDF
38. Staple line coverage with absorbable mesh after thoracoscopic bullectomy for spontaneous pneumothorax.
- Author
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Sakamoto, K., Takei, H., Nishii, T., Maehara, T., Omori, T., Tajiri, M., Imada, T., and Takanashi, Y.
- Subjects
- *
PNEUMOTHORAX , *RESPIRATORY diseases , *PATIENTS , *DIAGNOSIS , *CHEST (Anatomy) , *SYMPTOMS , *BLISTERS , *THORACIC surgery , *COMPARATIVE studies , *LENGTH of stay in hospitals , *LONGITUDINAL method , *RESEARCH methodology , *MEDICAL cooperation , *REOPERATION , *RESEARCH , *STAPLERS (Surgery) , *DISEASE relapse , *EVALUATION research , *TREATMENT effectiveness , *RETROSPECTIVE studies , *PLEURODESIS , *SURGICAL meshes - Abstract
Background: Thoracoscopic simple bullectomy for primary spontaneous pneumothorax (PSP) has a relatively high postoperative recurrence rate and sometimes results in postoperative air leakage. One of the reasons for postoperative recurrence is the regrowth of bullae around the staple line. Therefore, reinforcement of the visceral pleura around the staple line is a reasonable way to prevent postoperative air leaks and recurrence. This study was done to determine the efficacy in preventing postoperative air leak and recurrent pneumothorax of widely covering the staple line with absorbable mesh after thoracoscopic bullectomy.Methods: Wide coverage of the staple line with absorbable mesh was performed on 114 patients with PSP. These patients were retrospectively compared with 126 patients who underwent thoracoscopic simple bullectomy alone.Results: The postoperative duration of chest drainage in the coverage group (mean, 1 day; range, 0-5) was significantly shorter than that in the simple bullectomy group (mean, 3 days; range 0-20). A prolonged air leak (>7 days) occurred in six patients in the simple bullectomy group, but there were no such leaks in the coverage group. Recurrent pneumothorax occurred in three patients (2.6%) in the coverage group and 12 patients (9.5%) in the simple bullectomy group.Conclusion: Wide coverage of the staple line with absorbable mesh is effective in preventing postoperative air leak and in decreasing the recurrence rates of PSP. [ABSTRACT FROM AUTHOR]- Published
- 2004
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- View/download PDF
39. 5' adenosine monophosphate-activated protein kinase, metabolism and exercise.
- Author
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Aschenbach WG, Sakamoto K, and Goodyear LJ
- Abstract
The 5' adenosine monophosphate-activated protein kinase (AMPK) is a member of a metabolite-sensing protein kinase family that functions as a metabolic 'fuel gauge' in skeletal muscle. AMPK is a ubiquitous heterotrimeric protein, consisting of an alpha catalytic, and beta and gamma regulatory subunits that exist in multiple isoforms and are all required for full enzymatic activity. During exercise, AMPK becomes activated in skeletal muscle in response to changes in cellular energy status (e.g. increased adenosine monophosphate [AMP]/adenosine triphosphate [ATP] and creatine/phosphocreatine ratios) in an intensity-dependent manner, and serves to inhibit ATP-consuming pathways, and activate pathways involved in carbohydrate and fatty-acid metabolism to restore ATP levels. Recent evidence shows that although AMPK plays this key metabolic role during acute bouts of exercise, it is also an important component of the adaptive response of skeletal muscles to endurance exercise training because of its ability to alter muscle fuel reserves and expression of several exercise-responsive genes. This review discusses the putative roles of AMPK in acute and chronic exercise responses, and suggests avenues for future AMPK research in exercise physiology and biochemistry. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
40. Formation of a Rhenium-Base Coating on a Nb-Base Alloy.
- Author
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Fukumoto, M., Matsumura, Y., Hayashi, S., Sakamoto, K., Kasama, A., Tanaka, R., and Narita, T.
- Subjects
RHENIUM alloys ,RHENIUM ,NIOBIUM ,TRANSITION metals ,ALLOYS ,METALLIC composites ,METALS - Abstract
To protect Nb-5Mo-15W alloy against high-temperature oxidation a novel coating was developed involving electroplating of a Re-Ni film, followed by pack cementation with Cr and Al. The coating consisted of a duplex-layer structure, an inner σ (Re-Cr) or Re(Cr) layer and an outer α Cr(Al) or β NiAl layer. The Re-Ni film containing more than 70 at.% Re, developed in the present investigation, is more useful than the conventional low Re-Ni film. The inner a (Re-Cr) and Re(Cr) layer acts as a diffusion barrier between the Nb5Mo-15W alloy substrate and the outer α-Cr(Al) or β-NiAl layer, which forms a protective α-Al[sub 2]O[sub 3] scale. The coated Nb-5 Mo-15W alloy was oxidized in air at 1373 K for up to 360 ks, showing very good oxidation resistance. [ABSTRACT FROM AUTHOR]
- Published
- 2003
- Full Text
- View/download PDF
41. Deconstructing scalar QED at zero and finite temperature.
- Author
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Kan, N., Sakamoto, K., and Shiraishii, K.
- Subjects
- *
QUANTUM electrodynamics , *QUANTUM field theory , *QUANTUM theory , *RELATIVITY (Physics) , *SCALAR field theory , *BOSONS , *PARTICLES (Nuclear physics) , *BESSEL functions - Abstract
We calculate the effective potential for the WLPNGB in a world with a circular latticized extra dimension. The mass of the Wilson line pseudo-Nambu-Goldstone boson (WLPNGB) is calculated from the one-loop quantum effect of scalar fields at zero and finite temperature. We show that a series expansion by the modified Bessel functions is useful to calculate the one-loop effective potentials. [ABSTRACT FROM AUTHOR]
- Published
- 2003
- Full Text
- View/download PDF
42. Effects of IGF-I gene therapy on the injured rat pudendal nerve.
- Author
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Kerns, J. M., Shott, S., Brubaker, L., Sakamoto, K., Benson, J. T., Fleischer, A. E., and Coleman, M. E.
- Abstract
Injured nerves and their motor units may undergo enhanced recovery when exposed to recombinant human insulin-like growth factor-I (rhIGF-I). The external anal sphincter muscle in the female rat was denervated to model incontinence. The treatment-group muscle was injected with rhIGF-1 plasmid, whereas in the control group the plasmid lacked the cDNA insert and the normal group received neither surgery nor treatment. Electromyography data at 56 days post surgery indicated more reinnervation without fibrillation potentials in the treatment group (2 of 6) than in the control group (0 of 6). The histology of the regenerated axons in the pudendal nerve distal to the crush site also suggested an improved recovery in the treatment group. The number of motor neurons retrogradely labeled with horseradish peroxidase was decreased by 50% following pudendal nerve crush in both experimental groups compared to the normal group. We conclude from these preliminary results that rhIGF-I gene therapy may improve the distal recovery of structure and function. [ABSTRACT FROM AUTHOR]
- Published
- 2003
- Full Text
- View/download PDF
43. Methyl isobutyl ketone and methyl ethyl ketone in urine as biological markers of occupational exposure to these solvents at low levels.
- Author
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Kawai, T., Zhang, Z.-W., Takeuchi, A., Miyama, Y., Sakamoto, K., Higashikawa, K., and Ikeda, M.
- Subjects
KETONES ,URINALYSIS ,BIOMARKERS ,OCCUPATIONAL medicine ,OCCUPATIONAL diseases ,MULTIPLE regression analysis - Abstract
Objective. To examine whether unmetabolized methyl isobutyl ketone in urine is a useful marker of low-level occupational exposure to this ketone solvent, as is the case for methyl ethyl ketone. Methods. The study was conducted in the second half of a working week. In total, 27 furniture-making workers (19 men and eight women) and 11 non-exposed controls (six men and five women) volunteered to participate in the study. Time-weighted average (TWA; 8-h) concentration of vapors of several solvents in air, including methyl isobutyl ketone (MIBK-A) and methyl ethyl ketone (MEK-A) was monitored by diffusive sampling. Urine samples collected at the end of the shift were subjected to head-space gas chromatography (GC) analysis for the unmetabolized solvents (i.e., MIBK-U and MEK-U). The relationship between the concentration of the solvent vapor and the corresponding solvent level in urine was examined by simple as well as multiple regression analysis. Results. The exposures to MIBK and MEK were well below the current occupational exposure limit levels, but the maximum levels of exposure to toluene and ethylbenzene were around the corresponding exposure limit. The correlation of the TWA concentration of the solvent in air with the concentration of the corresponding solvent in the end-of-shift urine sample was significant both for MIBK and for MEK, and the correlation coefficient was larger for MIBK than for MEK. The slope in the exposure–excretion regression line was almost twice as steep for MEK than for MIBK, possibly due to the difference in water solubility. Approximately 0.12% of MIBK absorbed in the lungs will be excreted into urine, whereas the yield for MEK was somewhat higher (0.19%). Conclusion. MIBK in urine is a good marker of exposure to MIBK, as in the case of MEK in urine for MEK exposure. [ABSTRACT FROM AUTHOR]
- Published
- 2003
- Full Text
- View/download PDF
44. Complications of bacillus Calmette-Guerin therapy in superficial urothelial cancer: clinical analysis and implications.
- Author
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Suzuki, S., Shinohara, N., Harabayashi, T., Taniguchi, A., Haga, K., Sato, S., Sakamoto, K., and Koyanagi, T.
- Abstract
Background: Intravesical bacillus Calmette-Guerin (BCG) therapy has been proven to be effective in the prophylaxis and treatment of superficial bladder cancer. However, several complications of BCG therapy have been reported. The aim of this study was to clarify the impact of BCG treatment-related side effects on the clinical outcome of patients with superficial urothelial cancer. Methods: We reviewed the medical records of 33 patients who underwent BCG instillation therapy in our department. After complete endoscopic tumor resection, intravesical or intrapelvic instillation of BCG (80 mg of the Tokyo strain) was performed every week for 8 weeks. BCG treatment-related side effects were classified as minor (persistence of symptoms or low-grade fever for less than 48 h) or major (persistence of symptoms or low-grade fever for more than 48 h, or high fever). Risk factors for major side effects and relationships between the occurrence of major side effects and subsequent tumor progression were evaluated. Results: In total, there were 43 courses of intravesical and intrapelvic instillations of BCG in 33 patients, 20 (46%) of which were associated with major side effects. Risk factors associated with the occurrence of major side effects could not be detected. Subsequent tumor progression was observed in 3 of the 16 patients (19%) with major side effects and in 10 of the 17 patients (59%) without them. Nine patients who discontinued BCG therapy because of major side effects experienced no tumor progression. Progression-free survival was significantly higher in patients with major side effects than in those without them. Conclusions: These results suggest that BCG therapy should be discontinued whenever major side effects occur, because this does not necessarily lead to an unfavorable outcome regarding tumor progression. [ABSTRACT FROM AUTHOR]
- Published
- 2002
- Full Text
- View/download PDF
45. Toluene, xylenes and xylene isomers in urine as biological indicators of low-level exposure to each solvent; a comparative study.
- Author
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Takeuchi, A., Kawai, T., Zhang, Z.-W., Miyama, Y., Sakamoto, K., Higashikawa, K., and Ikeda, M.
- Subjects
PLASTICIZERS ,SOLUTION (Chemistry) ,SOLVENTS ,CHROMATOGRAPHIC analysis ,ORGANIC solvents ,MULTIVARIATE analysis - Abstract
Objective. To examine if xylenes and xylene isomers in end-of-shift urine are good biological indicators of low-level exposure to each solvent, similarly to toluene in urine. Methods. The study was conducted in the latter half of a working week. Furniture makers, 86 subjects in total (76 men and ten women), participated in the study in combination with 11 non-exposed subjects. Time-weighted average (8-h TWA) exposures to mixtures of toluene (TOL-A), xylenes (XYLs-A), ethylbenzene (EB-A), acetone (ACE-A) etc. were monitored with diffusive samplers for lipophilic and hydrophilic solvents, respectively. Urine samples (i.e., TOL-U, XYLs-U, EB-U, ACE-U, etc.) were collected at the end of the shift and subjected to head-space gas chromatography analysis for each solvent. The exposure–excretion relationship was examined by simple as well as multiple regression analysis. Results. The exposures to TOL and XYLs were around or below current occupational exposure limit levels. The exposures to other solvents [i.e., ACE, EB, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), etc.] were at substantially lower levels. The correlation of the TWA solvent exposure concentration with the concentration of the corresponding solvent in the end-of-shift urine sample was close for TOL, and also almost equally close in the case of XYLs and each of the three XYL isomers. Whereas the slope of the regression line for XYLs was significantly less steep than that for TOL when compared on an equi-molar basis, there was no difference among the three XYL isomers. No confounding effects of age, sex and co-exposure to other solvents were detected. The observation confirms previous reports that TOL-U is a good marker of TOL vapor exposure, indicates that XYL-U is also a reliable marker of exposure to vapors of XYLs or any of the three XYL isomers, and suggests that estimation of exposure to vapors of XYLs (i.e., three isomers in combination) is possible by the determination of one of the XYL isomers in urine, once the proportion of the isomers in air is known. Possible association of water solubility with solvent levels in urine is discussed. Conclusions Biological monitoring of exposure by means of analysis of end-of-shift urine for mother solvent is possible, not only in the case of TOL as previously reported, but also in cases of XYLs, either for three isomers in combination or separately. [ABSTRACT FROM AUTHOR]
- Published
- 2002
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- View/download PDF
46. Receiver operating characteristic (ROC) analysis of images reconstructed with iterative expectation maximization algorithms.
- Author
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Takahashi, Yasuyuki, Murase, Kenya, Higashino, Hiroshi, Sogabe, Ichiro, Sakamoto, Kana, Takahashi, Y, Murase, K, Higashino, H, Sogabe, I, and Sakamoto, K
- Abstract
Purpose: The quality of images reconstructed by means of the maximum likelihood-expectation maximization (ML-EM) and ordered subset (OS)-EM algorithms, was examined with parameters such as the number of iterations and subsets, then compared with the quality of images reconstructed by the filtered back projection method.Methods: Phantoms showing signals inside signals, which mimicked single-photon emission computed tomography (SPECT) images of cerebral blood flow and myocardial perfusion, and phantoms showing signals around the signals obtained by SPECT of bone and tumor were used for experiments. To determine signals for recognition, SPECT images in which the signals could be appropriately recognized with a combination of fewer iterations and subsets of different sizes and densities were evaluated by receiver operating characteristic (ROC) analysis. The results of ROC analysis were applied to myocardial phantom experiments and scintigraphy of myocardial perfusion.Results: Taking the image processing time into consideration, good SPECT images were obtained by OS-EM at iteration No. 10 and subset 5. CONCLULSION: This study will be helpful for selection of parameters such as the number of iterations and subsets when using the ML-EM or OS-EM algorithms. [ABSTRACT FROM AUTHOR]- Published
- 2001
- Full Text
- View/download PDF
47. Synthesis and evaluation of various layered octacalcium phosphates by wet-chemical processing.
- Author
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Nakahira, A., Aoki, S., Sakamoto, K., and Yamaguchi, S.
- Abstract
Octacalcium phosphate was synthesized by hydrolysis of α-tricalcium phosphate through a wet-chemical processing. Using the same wet-chemical processing in presence of various succinate ions, the preparation of some complexed octacalcium phosphates was attempted. The products were examined by X-ray diffraction method. These complexed octacalcium phosphates intercalated with succinic acid, L-asparatic acid, and methyl succinic acid showed an expanded basal spacing in the octacalcium phosphate unit cell dimensions. The microstructure was observed by scanning and transmission electron microscopy. © 2001 Kluwer Academic Publishers [ABSTRACT FROM AUTHOR]
- Published
- 2001
- Full Text
- View/download PDF
48. Emission Control of SO2 by Dry Coal-Cleaning and Bio-Briquette Technology.
- Author
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Sakamoto, K., Terauchi, Y., Ishitani, O., Kamide, M., and Wang, Q.
- Subjects
COMBUSTION ,EMISSION control ,AIR pollution ,ACID rain ,POLLUTANTS ,WATER reuse - Abstract
In China, the large amount of sulfur dioxide and dust discharged from the combustion of low-grade raw coal causes severe air pollution and acid rain. Therefore, the need to control the emission of such pollutants is urgent. It is well known that wet coal-cleaning technology is used to prepare clean coal from low-grade raw coal containing large amounts of sulfur and ash. However, this technology is not used in areas where water is scarce or severely polluted, because of the high cost of treating the wastewater. In an attempt to overcome this limitation, we studied an integrated technology, which combines dry coal-cleaning and bio-briquetting technologies, to prepare clean coal from low-grade raw coal. In the dry coal-cleaning method, refined coal was separated from ash and other minerals containing inorganic sulfur as pyrite by means of the differences in their electrostatic character. Most of the sulfur left in the refined coal was organic sulfur. The residual ash was fixed in combustion ashes of bio-briquettes made from coal, biomass, and slaked lime (Ca/S mole ratio =2) under pressure. By combining these two technologies, we were able to decrease the emission of sulfur dioxide and ash by 70≈90% compared to the combustion of raw coal. [ABSTRACT FROM AUTHOR]
- Published
- 2001
- Full Text
- View/download PDF
49. Study on Dry Deposition of SO2-NOX onto Loess.
- Author
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Sorimachi, A., Sakai, M., Ishitani, O., Nishikawa, M., and Sakamoto, K.
- Subjects
ATMOSPHERIC deposition ,EVAPORATION (Meteorology) ,OXIDATION ,SURFACE chemistry ,ATMOSPHERIC water vapor ,MOISTURE - Abstract
In order to obtain information on dry deposition of SO
2 onto loess in China, the effects of water vapor and NO2 on SO2 deposition-oxidation processes were investigated in laboratory measurements. The deposition velocities of SO2 onto loess particles were 2.34–7.33 cm s-1 , were high in comparison with the other studies. Deposition of SO2 onto the particles was decreased with exposed time and amounts of SO2 , but was influenced by adsorption of water vapor onto the particles. On the other hand, oxidation of SO2 physically8 adsorbed was promoted by the coexistence of water vapor and NO2 . So, it was indicated that it was possible for water vapor and NO2 in the atmosphere to play an important role in dry deposition for the deposition-oxidation interaction between SO2 and loess particles. [ABSTRACT FROM AUTHOR]- Published
- 2001
- Full Text
- View/download PDF
50. Fine Particle Dry Deposition onto a Cropland — a Trial to Estimate Deposition Velocity.
- Author
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Utiyama, M., Fukuyama, T., Izumi, K., Sakamoto, K., Sekiguchi, K., Kim, W., Koyama, A., Aoki, M., and Hara, H.
- Subjects
ATMOSPHERIC deposition ,AIR pollution ,PARTICLES ,SPEED ,DIFFUSION ,GASES - Abstract
The dry deposition velocity of fine particles is usually on the order of several tenths of cm s
-1 , and accordingly, the concentration gradient of particles above the surface is very small. This makes the application of the gradient method to the determination of the particle deposition velocity very difficult. This study is a trial to find a way around this difficulty. The idea is to evaluate the thickness of the molecular diffusion layer, zb by simultaneously measuring the concentration gradient of gaseous species such as SO2 ; zb is obtained by combining the turbulent and molecular transport equations for the gas. Then the particle deposition velocity is estimated on the basis of zb and the Brownian diffusion coefficient with an assumption that zb is equal to the thickness of the Brownian diffusion layer. By applying this method to the data collected in a field observation, the velocity of deposition onto a cropland was estimated for submicron particles. [ABSTRACT FROM AUTHOR]- Published
- 2001
- Full Text
- View/download PDF
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