72 results on '"Misumi M"'
Search Results
2. Alterations of body mass index and body composition in atomic bomb survivors
- Author
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Tatsukawa, Y, Misumi, M, Yamada, M, Masunari, N, Oyama, H, Nakanishi, S, Fukunaga, M, and Fujiwara, S
- Published
- 2013
- Full Text
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3. Alterations of body mass index and body composition in atomic bomb survivors
- Author
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Tatsukawa, Y, primary, Misumi, M, additional, Yamada, M, additional, Masunari, N, additional, Oyama, H, additional, Nakanishi, S, additional, Fukunaga, M, additional, and Fujiwara, S, additional
- Published
- 2012
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4. P239 Examination about the adaptation of sentinel lymph node biopsy after neoadjuvant chemotherapy using 18F-fluoro-deoxyglucose emission tomography/computed tomography fusion imaging (18F-FDG PET/CT) in breast cancer
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Shigekawa, T., primary, Sugitani, I., additional, Takeuchi, H., additional, Misumi, M., additional, Nakamiya, N., additional, Sugiyama, M., additional, Fujiuchi, N., additional, Osaki, A., additional, and Saeki, T., additional
- Published
- 2011
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5. P207 Feasibility of Mammaprint risk assessment using vacuum-assisted breast biopsy (Mammotome) in early breast cancer
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Osaki, A., primary, Takeuchi, H., additional, Nakamiya, N., additional, Shigekawa, T., additional, Matsuura, K., additional, Misumi, M., additional, Fujiuchi, N., additional, Stork-Sloots, L., additional, Ouchi, T., additional, and Saeki, T., additional
- Published
- 2011
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6. P243 18F-fluoro-deoxyglucose emission tomography/computed tomography fusion imaging (18F-FDG PET/CT) is useful for selecting optimal patients suited for sentinel lymph node biopsy after primary systemic chemotherapy in breast cancer
- Author
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Shigekawa, T., primary, Sugitani, I., additional, Takeuchi, H., additional, Misumi, M., additional, Sugiyama, M., additional, Nakamiya, N., additional, Fujiuchi, N., additional, Osaki, A., additional, and Saeki, T., additional
- Published
- 2011
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7. A STUDY ON FATIGUE CRACK GROWTH UNDER OUT-OF-PHASE COMBINED LOADINGS
- Author
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Ohkawa, I., primary, Takahashi, H., additional, Moriwaki, M., additional, and Misumi, M., additional
- Published
- 1997
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8. The isolation and characterization of DNA polymerase alpha from spinach.
- Author
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Misumi, M and Weissbach, A
- Abstract
A DNA polymerase with the characteristics of the alpha class of eukaryotic DNA polymerases has been purified 1000-fold from spinach leaves. The enzyme has a molecular weight of 160,000 +/- 10,000 in its native form and is markedly inhibited by aphidicolin and N-ethylmaleimide, but not by dideoxynucleoside triphosphates. As isolated, the enzyme contains no detectable deoxyribonuclease activity. A catalytically active 12-kilodalton fragment of the DNA polymerase, apparently generated by endogenous proteolytic action, has also been purified. The native enzyme is found predominantly in the cytoplasmic fraction of broken leaf cell preparations and less than 10% is found associated with the nuclei.
- Published
- 1982
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9. The enthalpy of formation of erbium trifluoride
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Kim, Y.-C, Yano, H, Misumi, M, and Oishi, J
- Published
- 1979
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10. Spermidine alleviates thymopoiesis defects and aging of the peripheral T-cell population in mice after radiation exposure.
- Author
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Yoshida K, Liu Z, Kubo Y, Miura M, Yamaoka M, Nagamura H, Misumi M, and Kusunoki Y
- Abstract
The T cell aging process can be modified by genotoxic factors, including ionizing radiation, and metabolic controls, such as caloric restriction; the former accelerates and the latter retards the process. However, the mechanisms by which these systemic factors interact to cause T cell aging remain unclear. This study investigated the naïve T-cell pool, thymic cellularity, and transcriptome in mice irradiated with 3.8 Gy at 5 weeks of age and treated 13 months later with 30 mM spermidine (SPD), a metabolism regulator. The number of conventional naïve CD4 and CD8 T cells in the peripheral blood decreased 14 months after irradiation whereas the number of virtual memory naïve T cells, which increased with age, further increased by irradiation. However, these radiation-related changes were not significant in similarly irradiated mice that were subsequently treated with SPD. The numbers of total, double-positive, and single-positive thymocytes were decreased by irradiation, whereas none were decreased in the irradiated mice treated with SPD. RNA sequencing of thymus cells revealed 803 upregulated genes in irradiated mice compared with those in non-irradiated control mice, with these genes enriched in leukocyte activation and inflammatory cytokine production. However, only 22 genes were upregulated in irradiated and SPD-treated mice, suggesting a reversal of many radiation-induced gene expression changes. These findings suggest that SPD may alleviate radiation-induced acceleration of T-cell aging, particularly by mitigating reduced thymopoiesis and inflammation. Further research is warranted to explore the rejuvenating potential of SPD and its mechanisms of action in accelerated T-cell aging., (Copyright © 2024. Published by Elsevier Inc.)
- Published
- 2024
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11. A note on potential gains in precision of radiation risk estimates from joint analysis.
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Sposto R, Misumi M, and Cologne J
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- Humans, Risk Assessment methods, Likelihood Functions, Female, Male, Neoplasms, Radiation-Induced epidemiology
- Abstract
In estimating radiation-related risk of cancer and other diseases based on the RERF Life Span Study (LSS), joint analyses can be performed where multiple health outcome endpoints are combined in the same model, allowing some parameters to be estimated in common among all endpoints with possible increase in precision of radiation risk and other model parameter estimates. Using as a basis excess relative risk (ERR) and excess absolute risk (EAR) models of the type commonly used in analysis of LSS data at RERF, we use maximum likelihood theory to compute the asymptotic relative standard error of endpoint-specific radiation effect and other parameter estimates using joint analyses as compared to traditional independent analysis. We show that some gains in precision of endpoint-specific radiation risk parameter estimates can be achieved by sharing effect modifier and other model parameters, but only small or negligible gains in precision are achieved for endpoint-specific background modifying or effect modifying parameters when other model parameters are shared. The magnitude of the precision gain for radiation risk estimates depends on the number of endpoints, the baseline incidence rate of the endpoint, and the type of model being used., (© 2024. The Author(s).)
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- 2024
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12. Establishment and activity of the planning and acting network for low dose radiation research in Japan (PLANET): 2016-2023.
- Author
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Yamada Y, Imaoka T, Iwasaki T, Kobayashi J, Misumi M, Sakai K, Sugihara T, Suzuki K, Tauchi H, Yasuda H, Yoshinaga S, Sasatani M, Tanaka S, Doi K, Tomita M, Iizuka D, Kakinuma S, Sasaki M, and Kai M
- Subjects
- Animals, Humans, Dose-Response Relationship, Radiation, Japan, Research, Risk Assessment, Radiation Dosage
- Abstract
The Planning and Acting Network for Low Dose Radiation Research in Japan (PLANET) was established in 2017 in response to the need for an all-Japan network of experts. It serves as an academic platform to propose strategies and facilitate collaboration to improve quantitative estimation of health risks from ionizing radiation at low-doses and low-dose-rates. PLANET established Working Group 1 (Dose-Rate Effects in Animal Experiments) to consolidate findings from animal experiments on dose-rate effects in carcinogenesis. Considering international trends in this field as well as the situation in Japan, PLANET updated its priority research areas for Japanese low-dose radiation research in 2023 to include (i) characterization of low-dose and low-dose-rate radiation risk, (ii) factors to be considered for individualization of radiation risk, (iii) biological mechanisms of low-dose and low-dose-rate radiation effects and (iv) integration of epidemiology and biology. In this context, PLANET established Working Group 2 (Dose and Dose-Rate Mapping for Radiation Risk Studies) to identify the range of doses and dose rates at which observable effects on different endpoints have been reported; Working Group 3 (Species- and Organ-Specific Dose-Rate Effects) to consider the relevance of stem cell dynamics in radiation carcinogenesis of different species and organs; and Working Group 4 (Research Mapping for Radiation-Related Carcinogenesis) to sort out relevant studies, including those on non-mutagenic effects, and to identify priority research areas. These PLANET activities will be used to improve the risk assessment and to contribute to the revision of the next main recommendations of the International Commission on Radiological Protection., (© The Author(s) 2024. Published by Oxford University Press on behalf of The Japanese Radiation Research Society and Japanese Society for Radiation Oncology.)
- Published
- 2024
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13. Behcet's disease presenting as malignant hypertension induced by renovascular hypertension.
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Kinguchi S, Tamura M, Furuta R, Toyota K, Ishiga K, Kanaoka T, Azushima K, Wakui H, Hirawa N, and Tamura K
- Abstract
Hypertension is an uncommon manifestation of Behcet's disease, which is also an uncommon cause of renovascular hypertension. We herein report a case of malignant hypertension associated with unilateral renal artery stenosis due to vascular Behcet's disease. A 19-year-old man, who had no significant medical history, was referred to ophthalmology at our hospital because he was suspected to have uveitis and Vogt-Koyanagi-Harada syndrome. In addition to poor eyesight, he had been aware of a fever, loss of appetite, and weight loss for a month. He was admitted with markedly elevated blood pressure (222/140 mmHg), hypertensive retinopathy, and acute kidney injury, who was diagnosed with malignant hypertension. Laboratory findings showed high plasma renin activity and plasma aldosterone concentration, hypokalemia, and elevated inflammatory response. Computed tomography showed an atrophic right kidney and a compensatorily enlarged left kidney. Renal computed tomography angiography revealed severe and diffuse stenosis of the right renal artery, and stenosis of the ostium of celiac artery. Since he was suspected to have uveitis and his inflammatory responses were elevated on admission, we listed Behcet's disease as a differential diagnosis. Medical interview and examination focusing on Behcet's disease revealed that the patient had recurrent oral aphthous lesions and folliculitis, and a positive pathergy test, which led to the patient being diagnosed with vascular Behcet's disease. After admission, his blood pressure was well controlled with multiple antihypertensive drugs including an angiotensin receptor/neprilysin inhibitor, and his oral aphthous lesions and skin lesion were improved with colchicine. When young men who are at a higher risk for vascular Behcet's disease show renovascular hypertension with an elevated inflammatory reaction, vascular Behcet's disease should be considered as a differential diagnosis., (© 2024. The Author(s), under exclusive licence to Japanese Society of Nephrology.)
- Published
- 2024
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14. Risk Ratio and Risk Difference Estimation in Case-cohort Studies.
- Author
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Noma H, Misumi M, and Tanaka S
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- Humans, Odds Ratio, Japan, Cohort Studies, Probability, Risk, Models, Statistical
- Abstract
Background: In case-cohort studies with binary outcomes, ordinary logistic regression analyses have been widely used because of their computational simplicity. However, the resultant odds ratio estimates cannot be interpreted as relative risk measures unless the event rate is low. The risk ratio and risk difference are more favorable outcome measures that are directly interpreted as effect measures without the rare disease assumption., Methods: We provide pseudo-Poisson and pseudo-normal linear regression methods for estimating risk ratios and risk differences in analyses of case-cohort studies. These multivariate regression models are fitted by weighting the inverses of sampling probabilities. Also, the precisions of the risk ratio and risk difference estimators can be improved using auxiliary variable information, specifically by adapting the calibrated or estimated weights, which are readily measured on all samples from the whole cohort. Finally, we provide computational code in R (R Foundation for Statistical Computing, Vienna, Austria) that can easily perform these methods., Results: Through numerical analyses of artificially simulated data and the National Wilms Tumor Study data, accurate risk ratio and risk difference estimates were obtained using the pseudo-Poisson and pseudo-normal linear regression methods. Also, using the auxiliary variable information from the whole cohort, precisions of these estimators were markedly improved., Conclusion: The ordinary logistic regression analyses may provide uninterpretable effect measure estimates, and the risk ratio and risk difference estimation methods are effective alternative approaches for case-cohort studies. These methods are especially recommended under situations in which the event rate is not low.
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- 2023
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15. Female "Paradox" in Atrial Fibrillation-Role of Left Truncation Due to Competing Risks.
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Nakamizo T, Misumi M, Takahashi T, Kurisu S, Matsumoto M, and Tsujino A
- Abstract
Female sex in patients with atrial fibrillation (AF) is a controversial and paradoxical risk factor for stroke-controversial because it increases the risk of stroke only among older women of some ethnicities and paradoxical because it appears to contradict male predominance in cardiovascular diseases. However, the underlying mechanism remains unclear. We conducted simulations to examine the hypothesis that this sex difference is generated non-causally through left truncation due to competing risks (CR) such as coronary artery diseases, which occur more frequently among men than among women and share common unobserved causes with stroke. We modeled the hazards of stroke and CR with correlated heterogeneous risk. We assumed that some people died of CR before AF diagnosis and calculated the hazard ratio of female sex in the left-truncated AF population. In this situation, female sex became a risk factor for stroke in the absence of causal roles. The hazard ratio was attenuated in young populations without left truncation and in populations with low CR and high stroke incidence, which is consistent with real-world observations. This study demonstrated that spurious risk factors can be identified through left truncation due to correlated CR. Female sex in patients with AF may be a paradoxical risk factor for stroke.
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- 2023
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16. Two cases of primary diffuse large B-cell lymphoma of the CNS associated with t(8;14)(q24;q32) or t(3;14)(q27;q32) identified by G-banding and fluorescence in situ hybridization applied to metaphase spreads.
- Author
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Ohno H, Maekawa F, Nakagawa M, Chagi Y, Nakagawa M, Kishimori C, Fukutsuka K, Hayashida M, Takeoka K, Maruyama W, Ukyo N, and Sumiyoshi S
- Subjects
- Male, Female, Humans, In Situ Hybridization, Fluorescence, Metaphase, Mutation, Chromosomes, Human, Pair 14 genetics, Translocation, Genetic, Lymphoma, Large B-Cell, Diffuse genetics, Lymphoma, Large B-Cell, Diffuse pathology
- Abstract
We describe two patients with primary diffuse large B-cell lymphoma of the central nervous system (PCNS-DLBCL). The first patient (case 1) was a woman in her late 70s who presented with a tumor in the left frontal lobe, whereas the second patient (case 2) was a man in his early 70s who presented with a left frontal lobe tumor associated with intratumoral hemorrhage. The histopathology of the tumor specimen disclosed the proliferation of large cells with centroblastic (case 1) or immunoblastic/plasmablastic (case 2) cytomorphology and an accumulation of the tumor cells within the perivascular space. The cells in both cases were positive for CD20, CD79a, BCL6, IRF4/MUM1, MYC, and BCL2 and negative for CD5 and CD10. G-banding revealed t(8;14)(q24;q32) in case 1, and the tetraploid-range karyotype including two or three copies of der(3)t(3;14)(q27;q32) and der(14)t(3;14)(q27;q32) in case 2. Fluorescence in situ hybridization applied to metaphase spreads confirmed colocalization of MYC and IGH (case 1) and BCL6 and IGH (case 2) hybridization signals on the relevant derivative chromosomes. Case 1 carried the MYD88
L265P mutation. This case report provides clear evidence for the occurrence of t(8;14)(q24;q32) and t(3;14)(q27;q32) in PCNS-DLBCL using metaphase-based cytogenetic analysis.- Published
- 2022
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17. Massive expansion of multiple clones in the mouse hematopoietic system long after whole-body X-irradiation.
- Author
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Yoshida K, Satoh Y, Uchimura A, Misumi M, Kyoizumi S, Taga M, Matsuda Y, Noda A, and Kusunoki Y
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- Animals, Bone Marrow radiation effects, Bone Marrow Cells, Clone Cells, Hematopoiesis genetics, Hematopoiesis radiation effects, Mice, Hematopoietic Stem Cells pathology, Whole-Body Irradiation adverse effects
- Abstract
Clonal hematopoiesis (CH) is prevalent in the elderly and associates with hematologic malignancy and cardiovascular disease. Although the risk of developing these diseases increases with radiation doses in atomic-bomb survivors, the causal relationship between radiation exposure and CH is unclear. This study investigated whether radiation exposure induces CH in mice 12-18 months after 3-Gy whole-body irradiation. We found radiation-associated increases in peripheral blood myeloid cells and red blood cell distribution width (RDW). Deep sequencing of bone marrow and non-hematopoietic tissue cells revealed recurrent somatic mutations specifically in the hematopoietic system in 11 of 12 irradiated mice but none in 6 non-irradiated mice. The irradiated mice possessed mutations with variant allele frequencies (VAFs) of > 0.02 on an average of 5.8 per mouse; mutations with VAFs of > 0.1 and/or deletion were prevalent. Examining hematopoietic stem/progenitor cells in two irradiated mice revealed several mutations co-existing in the same clones and multiple independent clones that deliver 60-80% of bone marrow nuclear cells. Our results indicate development of massive CH due to radiation exposure. Moreover, we have characterized mutations in radiation-induced CH., (© 2022. The Author(s).)
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- 2022
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18. Long-term dynamics of Norovirus transmission in Japan, 2005-2019.
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Misumi M and Nishiura H
- Abstract
Norovirus continues to evolve, adjusting its pathogenesis and transmissibility. In the present study, we systematically collected datasets on Norovirus outbreaks in Japan from 2005 to 2019 and analyzed time-dependent changes in the asymptomatic ratio, the probability of virus detection, and the probability of infection given exposure. Reports of 1,728 outbreaks were published, and feces from all involved individuals, including those with asymptomatic infection, were tested for virus in 434 outbreaks. We found that the outbreak size did not markedly change over this period, but the variance in outbreak size increased during the winter (November-April). Assuming that natural history parameters did not vary over time, the asymptomatic ratio, the probability of virus detection, and the probability of infection given exposure were estimated to be 18.6%, 63.3% and 84.5%, respectively. However, a model with time-varying natural history parameters yielded better goodness-of-fit and suggested that the asymptomatic ratio varied by year. The asymptomatic ratio was as high as 25.8% for outbreaks caused by genotype GII.4 noroviruses. We conclude that Norovirus transmissibility has not changed markedly since 2005, and that yearly variation in the asymptomatic ratio could potentially be explained by the circulating dominant genotype., Competing Interests: Hiroshi Nishiura is an Academic Editor for PeerJ. Otherwise the authors declare that they have no competing interests., (© 2021 Misumi and Nishiura.)
- Published
- 2021
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19. Association between low doses of ionizing radiation, administered acutely or chronically, and time to onset of stroke in a rat model.
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Takahashi N, Misumi M, Murakami H, Niwa Y, Ohishi W, Inaba T, Nagamachi A, and Suzuki G
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- Animals, Disease Models, Animal, Dose-Response Relationship, Radiation, Kaplan-Meier Estimate, Male, Proportional Hazards Models, Time Factors, Radiation, Ionizing, Stroke pathology
- Abstract
Exposure to high-doses of ionizing radiation has been reported to be associated with the risk of stroke. However, risks associated with lower dose exposures remain unclear, and there is little information available for the risk modification according to the dose-rate. There are few studies using animal models which might be able to provide complementary information on this association. In this study, the male stroke-prone spontaneously hypertensive rat (SHRSP) was used as a model animal. The rats were acutely irradiated with doses between 0 and 1.0 Gy or chronically irradiated with a cumulative dose of 0.5 or 1.0 Gy (at a dose rate of 0.05 or 0.1 Gy/day, respectively). The onset time of stroke related symptoms in SHRSP was used as an endpoint for evaluating the effects of low dose and the low dose-rate gamma-ray exposures. With respect to acute exposure, the time to the onset of stroke in the irradiated rats suggested the presence of a threshold around 0.1 Gy. For the low dose-rate chronically exposed, no significant increase in stroke symptom was observed. These findings are novel and demonstrate that the SHRSP system can be used to determine the association between the risk of stroke and radiation exposure with high sensitivity. Moreover, these studies provide important information regarding the association between the low dose and low dose-rate radiation exposure and circulatory diseases, especially stroke., (© The Author(s) 2020. Published by Oxford University Press on behalf of The Japanese Radiation Research Society and Japanese Society for Radiation Oncology.)
- Published
- 2020
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20. Association between a biomarker of glucose spikes, 1,5-anhydroglucitol, and cancer mortality.
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Kira S, Ito C, Fujikawa R, and Misumi M
- Subjects
- Deoxyglucose, Female, Humans, Male, Biomarkers, Blood Glucose, Glucose, Neoplasms blood, Neoplasms mortality
- Abstract
Introduction: 1,5-Anhydroglucitol (1,5-AG) is a biomarker of glucose spikes. To evaluate the effect of acute glucose excursions on cancer death, we clarified the association between 1,5-AG and cancer mortality among Japanese individuals with normal glucose tolerance., Research Design and Methods: We measured 1,5-AG in 6783 (2842 men, 3941 women) individuals with normal fasting and 2-hour plasma glucose who received a 75 g oral glucose tolerance test between 1994 and 2012. They were followed for mortality until August 2013. A systematic review of death certificates was used to confirm the cause of death. We divided the participants into four groups according to the quartile of 1,5-AG level at registration. We used Cox regression to clarify the association between 1,5-AG levels and cancer mortality with multivariate adjustment for possible confounders., Results: During the follow-up period (median, 10.0 years), 140 men and 109 women died of cancer. The HR for cancer mortality of the lowest quartile group was higher than that of the highest quartile group in men (HR, 2.62; 95% CI, 1.60 to 4.41) and in women (HR, 1.47; 95% CI, 0.88 to 2.47). These associations were not attenuated with further adjustment for HbA1c., Conclusions: 1,5-AG was associated with high risk of cancer mortality in Japanese men after adjustment for HbA1c., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2020
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21. Increased cancer mortality among Japanese individuals with hyperinsulinemia.
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Kira S, Ito C, Fujikawa R, and Misumi M
- Abstract
Aims: To evaluate the effect of hyperinsulinemia on cancer death, we clarified the association between hyperinsulinemia and cancer mortality among Japanese individuals., Methods: All the participants (5586 men and 6652 women) lived in Hiroshima City, underwent a 75 g oral glucose tolerance test between 1994 and 2012, and were followed for mortality until August 2013. A systematic review of death certificates was used to confirm the cause of death., Results: During the follow-up period (median, 10.0 years), 587 participants died of cancer. Lung cancer was the most common cause of organ-specific death. We divided the participants into 3 groups according to the tertiles of fasting immunoreactive insulin (FIRI) levels (low, middle, and high groups). The high group had the highest mortality rate (5.5 per 1000 person-years). The hazard ratio (HR) for cancer mortality of the high group after adjustment for possible confounders, such as age, sex, body mass index, smoking status, alcohol intake, and radiation effects (model 1), was significantly higher than that of the low group (HR, 1.55; 95% confidence interval (CI), 1.23-1.95). In model 2 (model 1 plus fasting plasma glucose) and model 3 (model 1 plus HbA1c), the multivariate HRs for cancer mortality were 1.46 (95% CI, 1.15-1.85) and 1.48 (95% CI, 1.17-1.87), respectively.The HR for cancer death at high FIRI levels (per 1 μU/mL) was 1.04 (95% CI, 1.02-1.05) in all participants after adjusting for fasting plasma glucose level and other confounders. In the subgroup analysis, the HRs were 1.03 (95% CI, 0.98-1.09), 1.05 (95% CI, 1.02-1.08), and 1.04 (95% CI, 1.02-1.06) in the normal, prediabetes, and diabetes group, respectively., Conclusions: Hyperinsulinemia was associated with a high risk of cancer mortality and may be an important link between cancer mortality and diabetes or prediabetes., Competing Interests: The authors have no conflicts of interest to declare., (© 2020 The Authors.)
- Published
- 2020
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22. Longitudinal examination of pancreatic β-cell function in Japanese individuals.
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Fujikawa R, Ito C, Kira S, and Misumi M
- Subjects
- Blood Glucose analysis, Diabetes Mellitus, Type 2 epidemiology, Female, Follow-Up Studies, Glucose Tolerance Test, Humans, Incidence, Japan epidemiology, Longitudinal Studies, Male, Middle Aged, Prognosis, Retrospective Studies, Biomarkers analysis, Diabetes Mellitus, Type 2 pathology, Glycated Hemoglobin analysis, Insulin-Secreting Cells pathology, Obesity physiopathology
- Abstract
Aims/introduction: We carried out a retrospective, longitudinal analysis of β-cell function between a diabetes mellitus group, including those that progressed to diabetes mellitus during the follow-up period, and a diabetic type with glycated hemoglobin (HbA1c) <6.5 group, including those that progressed to a diabetic type during the follow-up period. β-Cell function was assessed using homeostasis model of assessment of β-cell function., Materials and Methods: The relationship between the duration of diabetes mellitus or the diabetic type and pancreatic β-cell function was compared between the diabetes mellitus group (1,817) and diabetic type with HbA1c <6.5 group (1,843) using results from an oral glucose tolerance test. Linear mixed effects models were used to analyze repeated measurements of oral glucose tolerance tests., Results: The slope of the regression line of β-cell function for the duration of the diabetes mellitus group was -2.2%/year before the diagnosis. The slope differed after the diagnosis, and the difference was 1.3. The slope of the diabetic type group was -1.2%/year, and no significant difference was observed in the slope before and after the diagnosis. β-Cell function at the onset was 54.3% in the diabetic type group and 40.6% in the diabetes mellitus group, and the slope of the regression line was significantly higher in the diabetes mellitus group. We divided the diabetes mellitus and diabetic type with HbA1c <6.5 groups into obese and non-obese participants. β-Cell function declined more with obesity., Conclusions: Subsequent declines in β-cell function were faster in the diabetes mellitus group than that in the diabetic type with HbA1c <6.5 group, and increased with obesity., (© 2019 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.)
- Published
- 2020
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23. Alteration in plasma docosahexaenoic acid levels following oral administration of ethyl icosapentate to rats.
- Author
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Onozato M, Okanishi Y, Akutsu M, Okumura I, Nemoto A, Takano K, Sakamoto T, Ichiba H, and Fukushima T
- Abstract
Objectives: Ethyl icosapentate, a prodrug of eicosapentaenoic acid (EPA), has been prescribed to not only hyperlipidemia, but also psychotic patients. We have examined the impact of an orally administered polyunsaturated fatty acid (PUFA), ethyl icosapentate, on the plasma concentrations of seven other types of fatty acids and one metabolite (3-hydroxybutyrate, 3-HB) using rats., Design: and Methods: A commercial omega-3 PUFA, EPA, formulation (ethyl icosapentate, Epadel®) was administered orally to Sprague-Dawley rats (15, 50, 100 mg/kg, n = 4-8) and changes in the plasma fatty acid concentrations were investigated by HPLC using fluorescence detection., Results: The concentration of an n -3 PUFA, docosahexaenoic acid (DHA), was significantly increased from 11.6 ± 1.45 (0 h) to 25.9 ± 6.54 μM (6 h) in rat plasma ( n = 8, p = 1.88 × 10
-2 ) at a dose of 100 mg/kg, as was the EPA concentration from 2.58 ± 0.16 (0 h) to 6.03 ± 2.20 μM (1 h) ( n = 8, p = 2.09 × 10-2 ), whereas concentrations of other fatty acids, such as α -linolenic acid, palmitoleic acid, arachidonic acid, linolenic acid, and oleic acid, were not significantly changed. In addition, the concentration of the ultimate fatty acid metabolite, 3-hydroxybutyrate (3-HB), was significantly increased (from 94.6 ± 10.2 to 217 ± 43.4, p = 5.41 × 10-3 ) 12 h after oral administration of ethyl icosapentate ( n = 8, 100 mg/kg)., Conclusions: This result suggests that intake of the EPA formulation contributed not only to an increase in EPA concentration, but also to increases in DHA and 3-HB concentrations in vivo ., Competing Interests: There are no conflicts of interest to report., (© 2019 The Authors.)- Published
- 2019
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24. Association of Weight Fluctuation With Mortality in Japanese Adults.
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Cologne J, Takahashi I, French B, Nanri A, Misumi M, Sadakane A, Cullings HM, Araki Y, and Mizoue T
- Subjects
- Adult, Body Mass Index, Cardiovascular Diseases physiopathology, Female, Follow-Up Studies, Humans, Japan epidemiology, Male, Neoplasms physiopathology, Prospective Studies, Young Adult, Body Weight physiology, Cardiovascular Diseases mortality, Neoplasms mortality
- Abstract
Importance: Weight cycling is associated with the risk of mortality from heart disease, but many studies have not distinguished between simple nonlinear (monotone) weight changes and more complex changes that reflect fluctuations., Objective: To assess whether extreme body weight variation is associated with mortality after controlling for nonlinear weight changes., Design, Setting, and Participants: In this prospective clinical cohort study, 4796 Japanese atomic bomb survivors were examined in the clinic as part of a biennial health examination and research program. The study consisted of a 20-year longitudinal baseline period (July 1, 1958, to June 30, 1978) and subsequent mortality follow-up of 27 years (July 1, 1978, to June 30, 2005) Participants were initially between the ages of 20 and 49 years during the baseline period and, throughout the baseline period, had no diagnoses of cardiovascular disease (CVD) or cancer and attended at least 7 of 10 scheduled examinations. Data analysis was performed from October 16, 2015, to May 13, 2016., Exposures: Residual variability in body mass index (BMI) during the baseline period., Main Outcomes and Measures: Outcomes were mortality from ischemic heart disease, cerebrovascular disease, other CVDs combined, other causes (except cancer), and cancer. Root mean squared error was calculated to capture individual residual variation in BMI after adjustment for baseline BMI trends, and the association of magnitude of residual variation with mortality was calculated as relative risk., Results: In total, 4796 persons (mean [SD] age, 35.0 [7.3] years at first baseline examination; 3252 [67.8%] female; mean [SD] BMI, 21.2 [2.8] at first baseline visit [20.6 (2.4) among men and 21.5 (2.9) among women]) participated in the study. During follow-up, 1550 participants died: 82 (5.3% of all deaths) of ischemic heart disease, 181 (11.7%) of cerebrovascular disease, 186 (12.0%) of other CVDs, 615 (39.7%) of cancer, and 486 (31.3%) of other causes. Magnitude of residual variation in weight was associated with all-cause mortality (relative risk, 1.25 for 1 U of additional variation; 95% CI, 1.06-1.47) and ischemic heart disease mortality (relative risk, 2.49; 95% CI, 1.41-4.38)., Conclusions and Relevance: The findings suggest that an association exists between weight variation and heart disease mortality and that weight loss interventions, if deemed to be necessary, should be considered carefully.
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- 2019
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25. Evaluation of Pathological Association between Stroke-Related QTL and Salt-Induced Renal Injury in Stroke-Prone Spontaneously Hypertensive Rat.
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Reza MF, Ngarashi D, Koike M, Misumi M, Ohara H, and Nabika T
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- Acute Kidney Injury chemically induced, Acute Kidney Injury pathology, Animals, Blood Pressure genetics, Collagen Type I genetics, Collagen Type I, alpha 1 Chain, Disease Models, Animal, Humans, Hypertension complications, Hypertension physiopathology, Kidney pathology, Rats, Rats, Inbred SHR genetics, Sodium Chloride adverse effects, Stroke chemically induced, Stroke complications, Stroke pathology, Acute Kidney Injury genetics, Hypertension genetics, Quantitative Trait Loci genetics, Stroke genetics
- Abstract
The stroke-prone spontaneously hypertensive rat (SHRSP) suffers from severe hypertension and hypertensive organ damage such as cerebral stroke and kidney injury under salt-loading. By a quantitative trait locus (QTL) analysis between SHRSP and SHR (the stroke-resistant parental strain of SHRSP), two major QTLs for stroke susceptibility were identified on chromosomes 1 and 18 of SHRSP, which were confirmed in congenic strains constructed between SHRSP and SHR. As the progression of renal dysfunction was suggested to be one of the key factors inducing stroke in SHRSP, we examined effects of the stroke-related QTLs on kidney injury using two congenic strains harboring either of SHRSP-derived fragments of chromosomes 1 and 18 in the SHR genome. The congenic strains were challenged with 1% NaCl solution for 4 weeks; measurement of systolic blood pressure and urinary isoprostane level (a marker for oxidative stress) and evaluation of renal injury by quantification of genetic marker expression and histological examination were performed. We found that the congenic rats with SHRSP-derived fragment of chromosome 18 showed more severe renal damage with higher expression of Col1α-1 (a genetic marker for renal fibrosis) and higher urinary isoprostane level. In contrast, the fragment of chromosome 1 from SHRSP did not give such effects on SHR. Blood pressure was not greater in either of the congenic strains when compared with SHR. We concluded that the QTL region on chromosome 18 might deteriorate salt-induced renal injury in SHR through a blood pressure-independent mechanism.
- Published
- 2019
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26. Association Between Prevalence of Peripheral Artery Disease and Radiation Exposure in the Atomic Bomb Survivors.
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Takahashi I, Cologne J, Haruta D, Yamada M, Takahashi T, Misumi M, Fujiwara S, Matsumoto M, Kihara Y, Hida A, and Ohishi W
- Subjects
- Aged, Aged, 80 and over, Ankle Brachial Index, Cardiovascular Diseases epidemiology, Cardiovascular Diseases etiology, Coronary Artery Disease epidemiology, Coronary Artery Disease etiology, Female, Humans, Japan epidemiology, Male, Peripheral Arterial Disease epidemiology, Prevalence, Risk Factors, Survivors statistics & numerical data, Nuclear Weapons, Peripheral Arterial Disease etiology, Radiation Exposure adverse effects
- Abstract
Background Past reports suggested that total-body irradiation at 0.5 to 1.0 Gy could be responsible for atherosclerosis. Peripheral artery disease ( PAD ) is a manifestation of systematic atherosclerosis. Whether the consequences of a low-to-moderate dose of radiation include increased risk of PAD remains to be determined. The purpose of this study was to examine the association between radiation exposure and prevalence of PAD among Japanese atomic bomb survivors. Methods and Results Radiation exposure from the atomic bombing was assessed in 3476 participants (41.1% men, mean age 74.8 years with SD 6.4 years) with a cross-sectional survey in 2010 to 2014. Left- and right-side ankle-brachial indexes and upstroke time ( UT ) were obtained using oscillometric VP -2000. PAD was defined as an ankle-brachial index of 1.0 or less or a prior history related to revascularization. UT was considered a sensitive marker of early-stage PAD . Association between radiation exposure and PAD or UT was assessed using multivariable regression analyses with adjustment for potential confounding factors. Of 3476 participants, 79 (2.3%) were identified as having prevalent PAD . Multivariate logistic regression analysis indicated that radiation dose was unrelated to PAD prevalence (odds ratio, 0.83; 95% confidence interval [0.57-1.21]). UT appeared to increase with radiation dose, but the increase was not statistically significant (1.09 ms/Gy; 95% confidence interval [-0.17 to 2.36]). Conclusions We found no clear association of radiation dose with PAD , but it remains to be determined whether UT is associated with radiation dose.
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- 2018
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27. SDN Based End-to-End Inter-Domain Routing Mechanism for Mobility Management and Its Evaluation.
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Hata M, Soylu M, Izumi S, Abe T, and Suganuma T
- Abstract
Nowadays, due to the widespread usage of mobile devices and wireless network technologies, we can use various ICT services almost anytime, anywhere even if we are changing our location at that moment. Therefore, mobility management technology have been attracting attention. This technology is to keep communication alive even when a mobile node (MN), which is communicating with the server or some nodes, moves to another network domain. Software Defined Networking (SDN) is used for mobility management to realize effective intra-domain routing that optimizes routes when an MN moves inside an SDN domain. However, many of the approaches mainly focus on intra-domain routing and it is difficult to optimize inter-domain route. In this paper, we focus on this routing optimization problem and propose an SDN based end-to-end routing mechanism specified for mobility management. The proposed routing mechanism can optimize an end-to-end route based on various parameters such as bandwidth, number of domains, and flow operations for mobility after an MN has moved across SDN domains. We carried out some simulational experimentations to evaluate the effect of proposal. It is shown that the proposed routing mechanism can reduce communication delay and enhance network performance. Thus, the proposed routing mechanism can realize effective ICT services.
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- 2018
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28. Stepwise approach to SNP-set analysis illustrated with the Metabochip and colorectal cancer in Japanese Americans of the Multiethnic Cohort.
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Cologne J, Loo L, Shvetsov YB, Misumi M, Lin P, Haiman CA, Wilkens LR, and Le Marchand L
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- Cohort Studies, Colorectal Neoplasms ethnology, Colorectal Neoplasms pathology, Genome-Wide Association Study, Genotype, Humans, Japan, Receptor, Transforming Growth Factor-beta Type II genetics, Receptor, Transforming Growth Factor-beta Type II metabolism, Risk, Signal Transduction genetics, Smad7 Protein genetics, Smad7 Protein metabolism, Transforming Growth Factor beta genetics, Transforming Growth Factor beta metabolism, Asian genetics, Colorectal Neoplasms genetics, Polymorphism, Single Nucleotide
- Abstract
Background: Common variants have explained less than the amount of heritability expected for complex diseases, which has led to interest in less-common variants and more powerful approaches to the analysis of whole-genome scans. Because of low frequency (low statistical power), less-common variants are best analyzed using SNP-set methods such as gene-set or pathway-based analyses. However, there is as yet no clear consensus regarding how to focus in on potential risk variants following set-based analyses. We used a stepwise, telescoping approach to analyze common- and rare-variant data from the Illumina Metabochip array to assess genomic association with colorectal cancer (CRC) in the Japanese sub-population of the Multiethnic Cohort (676 cases, 7180 controls). We started with pathway analysis of SNPs that are in genes and pathways having known mechanistic roles in colorectal cancer, then focused on genes within the pathways that evidenced association with CRC, and finally assessed individual SNPs within the genes that evidenced association. Pathway SNPs downloaded from the dbSNP database were cross-matched with Metabochip SNPs and analyzed using the logistic kernel machine regression approach (logistic SNP-set kernel-machine association test, or sequence kernel association test; SKAT) and related methods., Results: The TGF-β and WNT pathways were associated with all CRC, and the WNT pathway was associated with colon cancer. Individual genes demonstrating the strongest associations were TGFBR2 in the TGF-β pathway and SMAD7 (which is involved in both the TGF-β and WNT pathways). As partial validation of our approach, a known CRC risk variant in SMAD7 (in both the TGF-β and WNT pathways: rs11874392) was associated with CRC risk in our data. We also detected two novel candidate CRC risk variants (rs13075948 and rs17025857) in TGFBR2, a gene known to be associated with CRC risk., Conclusions: A stepwise, telescoping approach identified some potentially novel risk variants associated with colorectal cancer, so it may be a useful method for following up on results of set-based SNP analyses. Further work is required to assess the statistical characteristics of the approach, and additional applications should aid in better clarifying its utility.
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- 2018
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29. Body composition and development of diabetes: a 15-year follow-up study in a Japanese population.
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Tatsukawa Y, Misumi M, Kim YM, Yamada M, Ohishi W, Fujiwara S, Nakanishi S, and Yoneda M
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- Abdominal Fat physiology, Aged, Female, Humans, Japan epidemiology, Longitudinal Studies, Male, Middle Aged, Body Composition physiology, Diabetes Mellitus epidemiology, Diabetes Mellitus physiopathology
- Abstract
Background/objectives: Few longitudinal studies have examined the association between diabetes risk and body composition in Asians. The aim of this prospective cohort study was to determine the role of body composition, estimated by whole-body dual-energy X-ray absorptiometry, in the development of diabetes and to examine the impact of body composition on diabetes risk in normal weight (body mass index (BMI) <23 kg/m
2 ) and overweight/obese groups (≥23 kg/m2 )., Subjects/methods: We measured the body composition for 1532 diabetes-free subjects (463 men and 1069 women), aged 48-79 years, at the baseline examination period from 1994-96 and followed-up to detect new cases of diabetes over the next 15 years (median 13.4 years)., Results: After being adjusted for BMI and other potential confounding factors, body fat distribution was associated with diabetes risk. Percentage of trunk fat was positively associated with the development of diabetes (hazards ratio (HR) per 1 SD (95% confidential interval (CI)), 1.58 (1.10-2.28) in men, and 1.34 (0.99-1.83) in women), and percentage of leg fat was negatively associated with the development of diabetes (HR per 1 SD (95% CI), 0.68 (0.50-0.91) in men and 0.68 (0.55-0.85) in women). The estimated HRs of % trunk and leg fat on the development of diabetes differed little between normal weight and overweight/obese subjects. Appendicular lean mass was also negatively associated with diabetes risk only in normal weight men., Conclusions: Opposite associations of trunk fat and leg fat with diabetes risk were observed. Assessment of body composition might help in the evaluation of diabetes risk.- Published
- 2018
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30. Dominant prevalence of Porphyromonas gingivalis fimA types I and IV in healthy Japanese children.
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Shimoyama Y, Ohara-Nemoto Y, Kimura M, Nemoto TK, Tanaka M, and Kimura S
- Abstract
Background/purpose: Porphyromonas gingivalis is a major causative agent of chronic periodontitis, whilst circumstances for acquisition of the bacterium remain to be elucidated. To examine prevalence of the bacterium harboring distinct fimA types in dental plaque of children, we established PCR procedures that are applicable for specimens with limited amounts. By this method, all six fimA types including type I and Ib were directly identified, and prevalence of fimA types and their frequency of guardian-child transmission in Japanese children were assessed., Materials and Methods: Genomic DNA was purified from dental plaque specimens of 132 periodontally healthy children (2-12 years old, 4.8 ± 0.2 years) and 19 mothers of resultant P. gingivalis- positive child subjects. PCR-based fimA genotyping was performed, and untypeable strains in the first PCR analysis were determined by a nested PCR., Results: P. gingivalis was found in 15.2% of the subjects (2-10 years old, 5.1 ± 0.6 years), and the most prevalent types were I and IV (37.0% each), followed by Ib and III (11.1% each), and then II (7.4%). Seven (35.0%) of the 20 P. gingivalis -positive subjects had combined colonization of type I with other fimA types. In most cases, bacterial prevalence and fimA types in the children were distinct from those of their mothers, indicating that its maternal transmission was not significant., Conclusion: These results suggest that colonization of non-disease-associated fimA types I and IV P. gingivalis to the oral cavity initiates from early childhood without showing any periodontal inflammation.
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- 2017
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31. Characterization of the influence of chlororespiration on the regulation of photosynthesis in the glaucophyte Cyanophora paradoxa.
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Misumi M and Sonoike K
- Subjects
- Cell Respiration, Chlorophyll metabolism, Cyanophora growth & development, Darkness, Kinetics, Phycobilisomes metabolism, Phycocyanin metabolism, Plastoquinone metabolism, Spectrometry, Fluorescence, Temperature, Chloroplasts metabolism, Cyanophora physiology, Photosynthesis
- Abstract
Glaucophytes are primary symbiotic algae with unique plastids called cyanelles, whose structure is most similar to ancestral cyanobacteria among plastids in photosynthetic organisms. Here we compare the regulation of photosynthesis in glaucophyte with that in cyanobacteria in the aim of elucidating the changes caused by the symbiosis in the interaction between photosynthetic electron transfer and other metabolic pathways. Chlorophyll fluorescence measurements of the glaucophyte Cyanophora paradoxa NIES-547 indicated that plastoquinone (PQ) pool in photosynthetic electron transfer was reduced in the dark by chlororespiration. The levels of nonphotochemical quenching of chlorophyll fluorescence was high in the dark but decreased under low light, and increased again under high light. This type of concave light dependence was quite similar to that observed in cyanobacteria. Moreover, the addition of ionophore hardly affected nonphotochemical quenching, suggesting state transition as a main component of the regulatory system in C. paradoxa. These results suggest that cyanelles of C. paradoxa retain many of the characteristics observed in their ancestral cyanobacteria. From the viewpoint of metabolic interactions, C. paradoxa is the primary symbiotic algae most similar to cyanobacteria than other lineages of photosynthetic organisms.
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- 2017
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32. Relationship Between Photochemical Quenching and Non-Photochemical Quenching in Six Species of Cyanobacteria Reveals Species Difference in Redox State and Species Commonality in Energy Dissipation.
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Misumi M, Katoh H, Tomo T, and Sonoike K
- Subjects
- Chlorophyll metabolism, Fluorescence, Kinetics, Oxidation-Reduction, Photosynthesis, Species Specificity, Spectrum Analysis, Cyanobacteria metabolism, Photochemical Processes
- Abstract
Although the photosynthetic reaction center is well conserved among different cyanobacterial species, the modes of metabolism, e.g. respiratory, nitrogen and carbon metabolism and their mutual interaction, are quite diverse. To explore such uniformity and diversity among cyanobacteria, here we compare the influence of the light environment on the condition of photosynthetic electron transport through Chl fluorescence measurement of six cyanobacterial species grown under the same photon flux densities and at the same temperature. In the dark or under weak light, up to growth light, a large difference in the plastoquinone (PQ) redox condition was observed among different cyanobacterial species. The observed difference indicates that the degree of interaction between respiratory electron transfer and photosynthetic electron transfer differs among different cyanobacterial species. The variation could not be ascribed to the phylogenetic differences but possibly to the light environment of the original habitat. On the other hand, changes in the redox condition of PQ were essentially identical among different species at photon flux densities higher than the growth light. We further analyzed the response to high light by using a typical energy allocation model and found that 'non-regulated' thermal dissipation was increased under high-light conditions in all cyanobacterial species tested. We assume that such 'non-regulated' thermal dissipation may be an important 'regulatory' mechanism in the acclimation of cyanobacterial cells to high-light conditions., (© The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.)
- Published
- 2016
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33. Ultrasonically enhanced extraction of luteolin and apigenin from the leaves of Perilla frutescens (L.) Britt. using liquid carbon dioxide and ethanol.
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Kawamura H, Mishima K, Sharmin T, Ito S, Kawakami R, Kato T, Misumi M, Suetsugu T, Orii H, Kawano H, Irie K, Sano K, Mishima K, Harada T, Mustofa S, Hasanah F, Siregar YD, Zahroh H, Putri LS, and Salim A
- Subjects
- Plant Leaves chemistry, Pressure, Solvents chemistry, Temperature, Time Factors, Apigenin isolation & purification, Carbon Dioxide chemistry, Chemical Fractionation methods, Ethanol chemistry, Luteolin isolation & purification, Perilla frutescens chemistry, Ultrasonic Waves
- Abstract
The present study reports on the ultrasonic enhancement of the liquid carbon dioxide (CO2) extraction of luteolin and apigenin from the leaves of Perilla frutescens (L.) Britt., to which ethanol is added as a cosolvent. The purpose of this research is also to investigate the effects of the particle size, temperature, pressure, irradiation power, irradiation time, and ethanol content in the liquid CO2 solution on the extraction yield using single-factor experiments. We qualitatively and quantitatively analyzed the yields in the extract using HPLC (high-performance liquid chromatography). The liquid CO2 mixed with ethanol was used at temperatures of 5, 20 and 25 °C with extraction pressures from 8 to 14 MPa. The yields of luteolin and apigenin in the extraction were clearly enhanced by the ultrasound irradiation, but the selectivity of the extract was not changed. The yields of luteolin and apigenin in the extract were also significantly improved by adjusting the operating temperature, the irradiation time, and the ethanol content in the liquid CO2 solution, but no change in the selectivity of the extract was observed., (Copyright © 2015 Elsevier B.V. All rights reserved.)
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- 2016
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34. Probing the Catalytic Mechanism of Copper Amine Oxidase from Arthrobacter globiformis with Halide Ions.
- Author
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Murakawa T, Hamaguchi A, Nakanishi S, Kataoka M, Nakai T, Kawano Y, Yamaguchi H, Hayashi H, Tanizawa K, and Okajima T
- Subjects
- Crystallography, X-Ray, Protein Structure, Tertiary, Amine Oxidase (Copper-Containing) chemistry, Arthrobacter enzymology, Bacterial Proteins chemistry, Copper chemistry
- Abstract
The catalytic reaction of copper amine oxidase proceeds through a ping-pong mechanism comprising two half-reactions. In the initial half-reaction, the substrate amine reduces the Tyr-derived cofactor, topa quinone (TPQ), to an aminoresorcinol form (TPQamr) that is in equilibrium with a semiquinone radical (TPQsq) via an intramolecular electron transfer to the active-site copper. We have analyzed this reductive half-reaction in crystals of the copper amine oxidase from Arthrobacter globiformis. Anerobic soaking of the crystals with an amine substrate shifted the equilibrium toward TPQsq in an "on-copper" conformation, in which the 4-OH group ligated axially to the copper center, which was probably reduced to Cu(I). When the crystals were soaked with substrate in the presence of halide ions, which act as uncompetitive and noncompetitive inhibitors with respect to the amine substrate and dioxygen, respectively, the equilibrium in the crystals shifted toward the "off-copper" conformation of TPQamr. The halide ion was bound to the axial position of the copper center, thereby preventing TPQamr from adopting the on-copper conformation. Furthermore, transient kinetic analyses in the presence of viscogen (glycerol) revealed that only the rate constant in the step of TPQamr/TPQsq interconversion is markedly affected by the viscogen, which probably perturbs the conformational change. These findings unequivocally demonstrate that TPQ undergoes large conformational changes during the reductive half-reaction., (© 2015 by The American Society for Biochemistry and Molecular Biology, Inc.)
- Published
- 2015
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35. Crystal structure of β-galactosidase from Bacillus circulans ATCC 31382 (BgaD) and the construction of the thermophilic mutants.
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Ishikawa K, Kataoka M, Yanamoto T, Nakabayashi M, Watanabe M, Ishihara S, and Yamaguchi S
- Subjects
- Catalytic Domain, Crystallization, Mutation, Protein Structure, Tertiary, Bacillus enzymology, beta-Galactosidase chemistry
- Abstract
Unlabelled: β-Galactosidase (EC 3.2.1.23) from Bacillus circulans ATCC 31382, designated BgaD, exhibits high transglycosylation activity to produce galacto-oligosaccharides. BgaD has been speculated to have a multiple domain architecture including a F5/8-type C domain or a discoidin domain in the C-terminal peptide region from amino acid sequence analysis. Here, we solved the first crystal structure of the C-terminal deletion mutant BgaD-D, consisting of sugar binding, Glyco_hydro, catalytic and bacterial Ig-like domains, at 2.5 Å. In the asymmetric unit, two molecules of BgaD-D were identified and the value of VM was estimated to be 5.0 Å(3) · Da(-1). It has been speculated that BgaD-D consists of four domains. From the structural analysis, however, we clarified that BgaD-D consists of five domains. We identified a new domain structure comprised of β-sheets in BgaD. The catalytic domain exhibits a TIM barrel structure with a small pocket suited for accommodating the disaccharides. Detailed structural information for the amino acid residues related to activity and substrate specificity was clarified in the catalytic domain. Furthermore, using the structural information, we successfully constructed some thermostable mutants via protein engineering method., Database: Coordinates for the BgaD-D structure have been deposited in the Protein Data Bank under accession code 4YPJ., (© 2015 FEBS.)
- Published
- 2015
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36. Contribution of a family 1 carbohydrate-binding module in thermostable glycoside hydrolase 10 xylanase from Talaromyces cellulolyticus toward synergistic enzymatic hydrolysis of lignocellulose.
- Author
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Inoue H, Kishishita S, Kumagai A, Kataoka M, Fujii T, and Ishikawa K
- Abstract
Background: Enzymatic removal of hemicellulose components such as xylan is an important factor for maintaining high glucose conversion from lignocelluloses subjected to low-severity pretreatment. Supplementation of xylanase in the cellulase mixture enhances glucose release from pretreated lignocellulose. Filamentous fungi produce multiple xylanases in their cellulase system, and some of them have modular structures consisting of a catalytic domain and a family 1 carbohydrate-binding module (CBM1). However, the role of CBM1 in xylanase in the synergistic hydrolysis of lignocellulose has not been investigated in depth., Results: Thermostable endo-β-1,4-xylanase (Xyl10A) from Talaromyces cellulolyticus, which is recognized as one of the core enzymes in the fungal cellulase system, has a modular structure consisting of a glycoside hydrolase family 10 catalytic domain and CBM1 at the C-terminus separated by a linker region. Three recombinant Xyl10A variants, that is, intact Xyl10A (Xyl10Awt), CBM1-deleted Xyl10A (Xyl10AdC), and CBM1 and linker region-deleted Xyl10A (Xyl10AdLC), were constructed and overexpressed in T. cellulolyticus. Cellulose-binding ability of Xyl10A CBM1 was demonstrated using quartz crystal microbalance with dissipation monitoring. Xyl10AdC and Xyl10AdLC showed relatively high catalytic activities for soluble and insoluble xylan substrates, whereas Xyl10Awt was more effective in xylan hydrolysis of wet disc-mill treated rice straw (WDM-RS). The enzyme mixture of cellulase monocomponents and intact or mutant Xyl10A enhanced the hydrolysis of WDM-RS glucan, with the most efficient synergism found in the interactions with Xyl10Awt. The increased glucan hydrolysis yield exhibited a linear relationship with the xylan hydrolysis yield by each enzyme. This relationship revealed significant hydrolysis of WDM-RS glucan with lower supplementation of Xyl10Awt., Conclusions: Our results suggest that Xyl10A CBM1 has the following two roles in synergistic hydrolysis of lignocellulose by Xyl10A and cellulases: enhancement of lignocellulosic xylan hydrolysis by binding to cellulose, and the efficient removal of xylan obstacles that interrupt the cellulase activity (because of similar binding target of CBM1). The combination of CBM-containing cellulases and xylanases in a fugal cellulase system could contribute to reduction of the enzyme loading in the hydrolysis of pretreated lignocelluloses.
- Published
- 2015
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37. Robust vehicle detection under various environments to realize road traffic flow surveillance using an infrared thermal camera.
- Author
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Iwasaki Y, Misumi M, and Nakamiya T
- Abstract
To realize road traffic flow surveillance under various environments which contain poor visibility conditions, we have already proposed two vehicle detection methods using thermal images taken with an infrared thermal camera. The first method uses pattern recognition for the windshields and their surroundings to detect vehicles. However, the first method decreases the vehicle detection accuracy in winter season. To maintain high vehicle detection accuracy in all seasons, we developed the second method. The second method uses tires' thermal energy reflection areas on a road as the detection targets. The second method did not achieve high detection accuracy for vehicles on left-hand and right-hand lanes except for two center-lanes. Therefore, we have developed a new method based on the second method to increase the vehicle detection accuracy. This paper proposes the new method and shows that the detection accuracy for vehicles on all lanes is 92.1%. Therefore, by combining the first method and the new method, high vehicle detection accuracies are maintained under various environments, and road traffic flow surveillance can be realized.
- Published
- 2015
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38. Identification of nuclear phosphoproteins as novel tobacco markers in mouse lung tissue following short-term exposure to tobacco smoke.
- Author
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Niimori-Kita K, Ogino K, Mikami S, Kudoh S, Koizumi D, Kudoh N, Nakamura F, Misumi M, Shimomura T, Hasegawa K, Usui F, Nagahara N, and Ito T
- Abstract
Smoking is a risk factor for lung diseases, including chronic obstructive pulmonary disease and lung cancer. However, the molecular mechanisms mediating the progression of these diseases remain unclear. Therefore, we sought to identify signaling pathways activated by tobacco-smoke exposure, by analyzing nuclear phosphoprotein expression using phosphoproteomic analysis of lung tissue from mice exposed to tobacco smoke. Sixteen mice were exposed to tobacco smoke for 1 or 7 days, and the expression of phosphorylated peptides was analyzed by mass spectrometry. A total of 253 phosphoproteins were identified, including FACT complex subunit SPT16 in the 1-day exposure group, keratin type 1 cytoskeletal 18 (K18), and adipocyte fatty acid-binding protein, in the 7-day exposure group, and peroxiredoxin-1 (OSF3) and spectrin β chain brain 1 (SPTBN1), in both groups. Semi-quantitative analysis of the identified phosphoproteins revealed that 33 proteins were significantly differentially expressed between the control and exposed groups. The identified phosphoproteins were classified according to their biological functions. We found that the identified proteins were related to inflammation, regeneration, repair, proliferation, differentiation, morphogenesis, and response to stress and nicotine. In conclusion, we identified proteins, including OSF3 and SPTBN1, as candidate tobacco smoke-exposure markers; our results provide insights into the mechanisms of tobacco smoke-induced diseases.
- Published
- 2014
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39. Monomer structure of a hyperthermophilic β-glucosidase mutant forming a dodecameric structure in the crystal form.
- Author
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Nakabayashi M, Kataoka M, Watanabe M, and Ishikawa K
- Subjects
- Archaeal Proteins genetics, Archaeal Proteins metabolism, Crystallography, X-Ray, Escherichia coli genetics, Escherichia coli metabolism, Gene Expression, Hot Temperature, Models, Molecular, Molecular Weight, Mutation, Protein Multimerization, Protein Stability, Protein Structure, Quaternary, Protein Structure, Secondary, Protein Structure, Tertiary, Pyrococcus furiosus enzymology, Recombinant Proteins chemistry, Recombinant Proteins genetics, Recombinant Proteins metabolism, beta-Glucosidase genetics, beta-Glucosidase metabolism, Archaeal Proteins chemistry, Pyrococcus furiosus chemistry, beta-Glucosidase chemistry
- Abstract
One of the β-glucosidases from Pyrococcus furiosus (BGLPf) is found to be a hyperthermophilic tetrameric enzyme that can degrade cellooligosaccharides. Recently, the crystal structures of the tetrameric and dimeric forms were solved. Here, a new monomeric form of BGLPf was constructed by removing the C-terminal region of the enzyme and its crystal structure was solved at a resolution of 2.8 Å in space group P1. It was discovered that the mutant enzyme forms a unique dodecameric structure consisting of two hexameric rings in the asymmetric unit of the crystal. Under biological conditions, the mutant enzyme forms a monomer. This result helps explain how BGLPf has attained its oligomeric structure and thermostability.
- Published
- 2014
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40. A new crystal form of a hyperthermophilic endocellulase.
- Author
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Kataoka M and Ishikawa K
- Subjects
- Archaeal Proteins genetics, Archaeal Proteins metabolism, Cellulases genetics, Cellulases metabolism, Crystallography, X-Ray, Escherichia coli genetics, Escherichia coli metabolism, Gene Expression, Hot Temperature, Hydrogen-Ion Concentration, Lignin chemistry, Lignin metabolism, Models, Molecular, Protein Structure, Tertiary, Pyrococcus furiosus enzymology, Recombinant Proteins chemistry, Recombinant Proteins genetics, Recombinant Proteins metabolism, beta-Glucans chemistry, beta-Glucans metabolism, Archaeal Proteins chemistry, Cellulases chemistry, Pyrococcus furiosus chemistry
- Abstract
The hyperthermophilic glycoside hydrolase family endocellulase 12 from the archaeon Pyrococcus furiosus (EGPf; Gene ID PF0854; EC 3.2.1.4) catalyzes the hydrolytic cleavage of the β-1,4-glucosidic linkage in β-glucan in lignocellulose biomass. A crystal of EGPf was previously prepared at pH 9.0 and its structure was determined at an atomic resolution of 1.07 Å. This article reports the crystallization of EGPf at the more physiologically relevant pH of 5.5. Structure determination showed that this new crystal form has the symmetry of space group C2. Two molecules of the enzyme are observed in the asymmetric unit. Crystal packing is weak at pH 5.5 owing to two flexible interfaces between symmetry-related molecules. Comparison of the EGPf structures obtained at pH 9.0 and pH 5.5 reveals a significant conformational difference at the active centre and in the surface loops. The interfaces in the vicinity of the flexible surface loops impact the quality of the EGPf crystal.
- Published
- 2014
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41. Is the association between smoking and the retinal venular diameter reversible following smoking cessation?
- Author
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Yanagi M, Misumi M, Kawasaki R, Takahashi I, Itakura K, Fujiwara S, Akahoshi M, Neriishi K, Wong TY, and Kiuchi Y
- Subjects
- Aged, Female, Follow-Up Studies, Humans, Male, Photography, Retinal Vein physiopathology, Retrospective Studies, Risk Factors, Recovery of Function, Retinal Vein pathology, Smoking adverse effects, Smoking Cessation, Venules physiology
- Abstract
Purpose: Wider retinal venular caliber is shown to be associated with an increased risk of stroke, and smoking is associated with a wider retinal venular caliber. However, the impact of smoking cessation on the retinal vessels has not been previously reported. We examined this issue in an adult cohort of atomic bomb survivors., Methods: In the Adult Health Study of Japanese atomic bomb survivors, 1664 subjects had retinal photographs taken from 2006 to 2008. The central retinal artery and vein equivalents (CRAE and CRVE) were calculated using a semiautomated software program. Multiple surveys have assessed the effects of smoking since 1963. The associations between smoking, the time since cessation, and the retinal vessel caliber were determined using linear mixed effects models., Results: The CRVE was associated with an increased number of cigarettes smoked per day among women after adjusting for potential confounding factors (age, sex, blood pressure, hypertensive medications, white blood cell count, diabetes, body mass index, lipids, and radiation dose). Females who smoked 10 cigarettes per day had a 6.9-μm wider mean CRVE (P = 0.001) than nonsmokers. Females who had stopped smoking for 10 or more years had a mean CRVE similar to those who had never smoked (191.8 vs. 194.4 μm; P = 0.23). These associations were not observed in males or for CRAE., Conclusions: Wider retinal venular caliber is associated with smoking in Japanese females; however, this association becomes nonsignificant after 10 or more years of smoking cessation, suggesting that the impact of smoking on retinal venular dilation is reversible following long-term smoking cessation.
- Published
- 2014
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42. Are all polar molecules hydrophilic? Hydration numbers of ketones and esters in aqueous solution.
- Author
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Shikata T and Okuzono M
- Abstract
Hydration numbers of typical polar compounds like ketones and esters in aqueous solution were precisely determined using high-frequency dielectric relaxation techniques up to a frequency of 50 GHz at 25 °C. Because the hydration number is one of the most quantitative parameters to demonstrate how much are molecules hydrophilic, it is a critical parameter to determine the hydrophilicity of compounds. Hydration numbers of some ketones bearing carbonyl groups were determined to be ca. 0 irrespective of the species of molecules. Moreover, hydration numbers of some esters were also evaluated to be ca. 0 as well as the ketones. These findings suggested that there is no hydrogen bond formation between the ester group and water molecules, nor is there the hydrogen bond formation between the carbonyl group and water molecules. Consequently, esters and ketones bearing typical polar groups are not classified into hydrophilic compounds, but into "hydroneutral" compounds positioned between hydrophilic and hydrophobic ones. Molecular motions of the examined polar molecules in aqueous solution were well described with single Debye-type rotational relaxation modes without strong interaction between solute and water molecules, and also between solute molecules because of the obtained Kirkwood factor close to unity. This independent rotational mode for the polar compounds results from the hydroneutral characteristics caused by the relationship n(H) = 0.
- Published
- 2013
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43. Robust vehicle detection under various environmental conditions using an infrared thermal camera and its application to road traffic flow monitoring.
- Author
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Iwasaki Y, Misumi M, and Nakamiya T
- Abstract
We have already proposed a method for detecting vehicle positions and their movements (henceforth referred to as "our previous method") using thermal images taken with an infrared thermal camera. Our experiments have shown that our previous method detects vehicles robustly under four different environmental conditions which involve poor visibility conditions in snow and thick fog. Our previous method uses the windshield and its surroundings as the target of the Viola-Jones detector. Some experiments in winter show that the vehicle detection accuracy decreases because the temperatures of many windshields approximate those of the exterior of the windshields. In this paper, we propose a new vehicle detection method (henceforth referred to as "our new method"). Our new method detects vehicles based on tires' thermal energy reflection. We have done experiments using three series of thermal images for which the vehicle detection accuracies of our previous method are low. Our new method detects 1,417 vehicles (92.8%) out of 1,527 vehicles, and the number of false detection is 52 in total. Therefore, by combining our two methods, high vehicle detection accuracies are maintained under various environmental conditions. Finally, we apply the traffic information obtained by our two methods to traffic flow automatic monitoring, and show the effectiveness of our proposal.
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- 2013
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44. Hydration/dehydration behavior of polyalcoholic compounds governed by development of intramolecular hydrogen bonds.
- Author
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Shikata T and Okuzono M
- Abstract
Hydration/dehydration behavior of polyalcoholic compounds with a rigid cyclohexane-type aliphatic molecular frame, such as 1,4-cyclohexanediol (ch(OH)2), 1α,3α,5α-cyclohexanetriol (cis-phloroglucitol, ch(OH)3), and cis-1,2,3,5-trans-4,6-cyclohexanehexaol (myo-inositol, ch(OH)6) was investigated using extremely high-frequency dielectric relaxation measurements up to 50 GHz over a temperature range from 10 to 70 °C. The temperature dependencies of hydration numbers per hydroxy group (mOH) in the polyalcoholic compounds were determined. Although the obtained mOH value was ca. 5 in a temperature range lower than 30 °C, it decreased and approached to ca. 3 with increasing temperature for ch(OH)2 and ch(OH)3, in which hydroxy groups hardly form intramolecular hydrogen bonds due to separations between them. This temperature-dependent hydration/dehydration behavior is characteristic of isolated hydroxy groups without intramolecular hydrogen bond formation. On the other hand, a constant mOH value of ca. 1 was observed irrespective of temperature for ch(OH)6. Because all the separations between adjacent hydroxy groups in ch(OH)6 are proper for (circular type) intramolecular hydrogen bond formation, the obtained temperature-independent small mOH value resulted from an inherent feature of intramolecularly hydrogen bonded hydroxy groups.
- Published
- 2013
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45. Conventional case-cohort design and analysis for studies of interaction.
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Cologne J, Preston DL, Imai K, Misumi M, Yoshida K, Hayashi T, and Nakachi K
- Subjects
- ErbB Receptors genetics, Humans, Japan epidemiology, Lung Neoplasms epidemiology, Models, Statistical, Neoplasms, Radiation-Induced epidemiology, Nuclear Warfare, Polymorphism, Genetic radiation effects, Radiation Injuries epidemiology, Case-Control Studies, Epidemiologic Methods, Research Design
- Abstract
Background: The case-cohort study design has received significant methodological attention in the statistical and epidemiological literature but has not been used as widely as other cohort-based sampling designs, such as the nested case-control design. Despite its efficiency and practicality for a wide range of epidemiological study purposes, researchers may not yet be aware of the fact that the design can be analysed using standard software with only minor adjustments. Furthermore, although the large number of options for design and analysis of case-cohort studies may be daunting, they can be reduced to a few simple recommendations., Methods: We review conventional methods for the design and analysis of case-cohort studies and describe empirical comparisons based on a study of radiation, gene polymorphisms and cancer in the Japanese atomic bomb survivor cohort., Results: Stratified, as opposed to simple, random subcohort selection is recommended, especially for studies of gene-environment interaction, which are notorious for lacking statistical power. Methods based on the score-unbiased exact pseudo-likelihood (or its analogue with stratified case-cohort data) are recommended for use in conjunction with the asymptotic variance estimator., Conclusions: We present an example of how to implement case-cohort analysis methods using SPSS, a popular statistical package that lacks some of the features necessary to directly adapt and implement published methods based on other software platforms. We also illustrate case-control analysis using Epicure, which provides greater risk-modelling flexibility than other software. Our conclusions and recommendations should help investigators to better understand and apply the case-cohort design in epidemiological research.
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- 2012
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46. Atomic resolution of the crystal structure of the hyperthermophilic family 12 endocellulase and stabilizing role of the DxDxDG calcium-binding motif in Pyrococcus furiosus.
- Author
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Kim HW, Kataoka M, and Ishikawa K
- Subjects
- Amino Acid Motifs, Archaeal Proteins genetics, Archaeal Proteins metabolism, Binding Sites, Calorimetry, Differential Scanning, Catalytic Domain, Cellulases genetics, Cellulases metabolism, Cellulose metabolism, Codon, Nonsense, Crystallography, X-Ray, Enzyme Stability, Hot Temperature, Isoenzymes chemistry, Isoenzymes genetics, Isoenzymes metabolism, Ligands, Peptide Fragments chemistry, Peptide Fragments genetics, Peptide Fragments metabolism, Protein Conformation, Recombinant Proteins chemistry, Recombinant Proteins metabolism, beta-Glucans metabolism, Archaeal Proteins chemistry, Calcium metabolism, Cellulases chemistry, Models, Molecular, Pyrococcus furiosus enzymology
- Abstract
Hyperthermophilic glycoside hydrolase family 12 endocellulase (EGPf) from the archaeon Pyrococcus furiosus catalyzes the hydrolytic cleavage of β-1,4-glucosidic linkage in β-glucan cellulose. A truncated EGPf (EGPfΔN30) mutant lacking the proline and hydroxyl-residue rich region at the N terminus was constructed, and its crystal structure was resolved at an atomic resolution of 1.07 Å. Our results indicate that the structure of EGPf, which consists of a β-jelly roll, exhibits structural similarity with the endocellulase of Thermotoga maritima. Additionally, we further determined that the thermostability of EGPf is maintained in part by the binding of Ca²⁺ in a DxDxDG Ca²⁺-binding motif, atypical of most archaeal proteins., (Copyright © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.)
- Published
- 2012
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47. Crystallization and preliminary X-ray analysis of a hyperthermophilic endoglucanase from Pyrococcus furiosus.
- Author
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Kataoka M, Kim HW, and Ishikawa K
- Subjects
- Crystallization, Crystallography, X-Ray, Enzyme Stability, Cellulase chemistry, Pyrococcus furiosus enzymology
- Abstract
The hyperthermophilic glycoside hydrolase family 12 endocellulase from the archaeon Pyrococcus furiosus (EGPf) catalyzes the hydrolytic cleavage of the β-1,4-glucosidic linkage in β-glucans in biomass. EGPf (Gene ID PF0854; EC 3.2.1.4) contains a signal sequence and proline- and hydroxyl-rich regions at the N-terminus. Truncated EGPf (EGPfΔN30) without the proline- and hydroxyl-rich regions at the N-terminus was prepared and subjected to crystallization experiments. Crystals were obtained using the hanging-drop vapour-diffusion method at 303 K. An X-ray diffraction data set was collected to 1.07 Å resolution at 100 K. The crystal belonged to space group P2(1)2(1)2, with unit-cell parameters a = 58.01, b = 118.67, c = 46.76 Å. The presence of one molecule of enzyme per asymmetric unit gives a crystal volume per protein mass (V(M)) of 2.63 Å(3) Da(-1) and a solvent content of 53.3%(v/v)., (© 2012 International Union of Crystallography)
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- 2012
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48. Detection of the reaction intermediates catalyzed by a copper amine oxidase.
- Author
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Kataoka M, Oya H, Tominaga A, Otsu M, Okajima T, Tanizawa K, and Yamaguchi H
- Subjects
- Amine Oxidase (Copper-Containing) chemistry, Arthrobacter enzymology, Catalysis, Crystallography, X-Ray, Dihydroxyphenylalanine analogs & derivatives, Dihydroxyphenylalanine chemistry, Dihydroxyphenylalanine metabolism, Phenethylamines chemistry, Phenethylamines metabolism, Schiff Bases, X-Ray Diffraction, Amine Oxidase (Copper-Containing) metabolism
- Abstract
To reveal the chemical changes and geometry changes of active-site residues that cooperate with a reaction is important for understanding the functional mechanism of proteins. Consecutive temporal analyses of enzyme structures have been performed during reactions to clarify structure-based reaction mechanisms. Phenylethylamine oxidase from Arthrobacter globiformis (AGAO) contains a copper ion and topaquinone (TPQ(ox)). The catalytic reaction of AGAO catalyzes oxidative deaminations of phenylethylamine and consists of reductive and oxidative half-reactions. In the reduction step, TPQ(ox) reacts with a phenylethylamine (PEA) substrate giving rise to a topasemiquinone (TPQ(sq)) formed Schiff-base and produces phenylacetaldehyde. To elucidate the mechanism of the reductive half-reaction, an attempt was made to trap the reaction intermediates in order to analyze their structures. The reaction proceeded within the crystals when AGAO crystals were soaked in a PEA solution and freeze-trapped in liquid nitrogen. The reaction stage of each crystal was confirmed by single-crystal microspectrometry, before X-ray diffraction measurements were made of four reaction intermediates. The structure at 15 min after the onset of the reaction was analyzed at atomic resolution, and it was shown that TPQ(ox) and some residues in the substrate channel were alternated via catalytic reductive half-reactions.
- Published
- 2011
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49. Biochemical characterization of calcineurin B-like-interacting protein kinase in Vicia guard cells.
- Author
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Tominaga M, Harada A, Kinoshita T, and Shimazaki K
- Subjects
- Amino Acid Sequence, Calcineurin metabolism, Calcium-Binding Proteins genetics, DNA, Complementary genetics, DNA, Plant genetics, Gene Expression Regulation, Plant, Mitochondrial Membranes metabolism, Molecular Sequence Data, Phosphorylation, Phylogeny, Plant Proteins genetics, Protein Binding, Protein Serine-Threonine Kinases genetics, Sequence Alignment, Vicia faba metabolism, Calcium metabolism, Calcium-Binding Proteins metabolism, Plant Proteins metabolism, Protein Serine-Threonine Kinases metabolism, Vicia faba genetics
- Abstract
Protein phosphorylation is crucial in the signaling of guard cells in response to various factors, including light, ABA and CO2, and calcium plays a central role in these signaling processes. Despite extensive studies on the functional role of Ca(2+)-regulated protein kinases in plants, relatively little is known about the biochemical properties of the kinases in guard cells. To investigate this, we isolated the VfCIPK1 [Vicia faba calcineurin B-like calcium-binding protein (CBL)-interacting protein kinase 1] cDNA from guard cells of Vicia faba L., which encodes a Ca(2+)-regulated protein kinase that belongs to the SnRK3 subgroup, and characterized VfCIPK1 at the biochemical level. VfCIPK1 genes were expressed in guard cells and roots, but not in mesophyll cells. The VfCIPK1 protein was localized on the outer membrane of mitochondria in guard cells and interacted with VfCBL1. The immunoprecipitation experiments indicated that VfCIPK1 interacted with VfCBL1 in vivo. The recombinant VfCIPK1 phosphorylated myelin basic protein as a substrate and the activity was increased by VfCBL1, and this activity showed a maximum in the absence of Ca2+ and decreased by an elevation of the Ca2+ concentration. A pull-down assay and the measurement of surface plasmon resonance indicated that the interaction between VfCIPK1 and VfCBL1 was decreased by Ca2+. These results suggest that VfCIPK1 may be negatively regulated by cytosolic Ca2+ through VfCBL1 and may be related to mitochondrial functions in guard cells. This is the first report that shows the inhibitory effect of Ca2+ on CIPK activity in the presence of CBL.
- Published
- 2010
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50. Pseudomyxoma peritonei occurring after an uneventful 23 years interval from appendectomy.
- Author
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Taii A, Sakagami J, Shinoda M, Taniguchi H, Tosa M, Baba T, Motoyoshi T, Ito R, Mitsufuji S, Kataoka K, and Okanoue T
- Subjects
- Adenocarcinoma, Mucinous diagnosis, Adenocarcinoma, Mucinous surgery, Adenocarcinoma, Papillary pathology, Aged, Diagnosis, Differential, Fatal Outcome, Humans, Lung Neoplasms pathology, Male, Peritoneal Neoplasms diagnosis, Peritoneal Neoplasms surgery, Pseudomyxoma Peritonei diagnosis, Pseudomyxoma Peritonei surgery, Time Factors, Adenocarcinoma, Mucinous etiology, Appendectomy adverse effects, Peritoneal Neoplasms etiology, Pseudomyxoma Peritonei etiology
- Abstract
A 77-year-old male was admitted to our hospital for a bulky abdominal mass. He had a history of appendectomy under the diagnosis of appendiceal rupture 23 years previously. He also had received a radical lung resection for an early lung cancer 2 years earlier in another hospital. Tentative diagnosis of peritoneal metastases from the lung cancer was made. He then received 3 courses of chemotherapy, but failed to reach a remission. The final diagnosis of pseudomyxoma peritonei was made by means of abdominocentesis, and he underwent debulking surgery. However, he died on day 56 after the surgery. Pseudomyxoma peritonei requires careful observation, as it has the possibility to be detected after a long-term follow-up period of more than 20 years.
- Published
- 2007
- Full Text
- View/download PDF
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