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1.
Phys Rev Lett ; 131(1): 011401, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37478426

RESUMO

We perform a general-relativistic neutrino-radiation magnetohydrodynamic simulation of a one second-long binary neutron star merger on the Japanese supercomputer Fugaku using about 85 million CPU hours with 20 736 CPUs. We consider an asymmetric binary neutron star merger with masses of 1.2M_{⊙} and 1.5M_{⊙} and a "soft" equation of state SFHo. It results in a short-lived remnant with the lifetime of ≈0.017 s, and subsequent massive torus formation with the mass of ≈0.05M_{⊙} after the remnant collapses to a black hole. For the first time, we find that after the dynamical mass ejection, which drives the fast tail and mildly relativistic components, the postmerger mass ejection from the massive torus takes place due to the magnetorotational instability-driven turbulent viscosity in a single simulation and the two ejecta components are seen in the distributions of the electron fraction and velocity with distinct features.

3.
Plant Cell Environ ; 44(2): 598-612, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33099780

RESUMO

Under phosphorus (P) deficiency, Lupinus albus develops cluster roots that allow efficient P acquisition, while L. angustifolius without cluster roots also grows well. Both species are non-mycorrhizal. We quantitatively examined the carbon budgets to investigate the different strategies of these species. Biomass allocation, respiratory rates, protein amounts and carboxylate exudation rates were examined in hydroponically-grown plants treated with low (1 µM; P1) or high (100 µM; P100) P. At P1, L. albus formed cluster roots, and L. angustifolius increased biomass allocation to the roots. The respiratory rates of the roots were faster in L. albus than in L. angustifolius. The protein amounts of the non-phosphorylating alternative oxidase and uncoupling protein were greater in the cluster roots of L. albus at P1 than in the roots at P100, but similar between the P treatments in L. angustifolius roots. At P1, L. albus exuded carboxylates at a faster rate than L. angustifolius. The carbon budgets at P1 were surprisingly similar between the two species, which is attributed to the contrasting root growth and development strategies. L. albus developed cluster roots with rapid respiratory and carboxylate exudation rates, while L. angustifolius developed a larger root system with slow respiratory and exudation rates.


Assuntos
Carbono/metabolismo , Ácidos Carboxílicos/metabolismo , Lupinus/fisiologia , Fósforo/deficiência , Transporte Biológico , Biomassa , Lupinus/anatomia & histologia , Lupinus/crescimento & desenvolvimento , Fósforo/metabolismo , Exsudatos de Plantas/química , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/enzimologia , Respiração
4.
Clin Biochem ; 73: 77-81, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31386833

RESUMO

OBJECTIVES: HbA1c shows low in patients with hemolysis, whereas glycated albumin (GA) is not affected by hemolysis. Therefore, the GA/HbA1c ratio reflects hemolysis in diabetic patients with hemolysis. Erythrocyte creatine (EC) is an indicator of hemolysis that reflects the mean erythrocyte age. The aim of this study was to examine whether HbA1c adjusted by EC accurately reflected glycemic control in patients with hemolysis. MATERIALS AND METHODS: A total of 238 individuals, consisting of 131 diabetic patients and 107 non-diabetic subjects, and consisting of 42 patients with hemolysis, and 196 subjects without hemolysis were selected for the study. HbA1c expressed in the IFCC units (iA1c) as well as in the NGSP units (A1C) were used. From the fact that EC and the GA/iA1c ratio showed a significant positive correlation, a formula for iA1c adjusted by EC (ECadj-iA1c) was created from a regression equation between EC and the GA/iA1c ratio. RESULTS: Significant correlations were observed between the GA/iA1c ratio and various hemolytic indicators but not between the GA/ECadj-iA1c ratio and those hemolytic indicators. The GA/iA1c ratio in individuals with hemolysis was significantly higher than in individuals without hemolysis, while no significant differences were observed in the GA/ECadj-iA1c ratio between the groups. Further, iA1c concentrations in non-diabetic patients with hemolysis were significantly lower than in the non-diabetic subjects without hemolysis, whereas ECadj-iA1c and GA concentrations showed no significant difference between the two groups. CONCLUSIONS: These results suggested that ECadj-iA1c accurately reflected glycemic control in patients with hemolysis.


Assuntos
Creatina/sangue , Diabetes Mellitus/sangue , Eritrócitos/metabolismo , Hemoglobinas Glicadas/metabolismo , Hemólise , Idoso , Diabetes Mellitus/patologia , Eritrócitos/patologia , Feminino , Produtos Finais de Glicação Avançada , Humanos , Masculino , Pessoa de Meia-Idade , Albumina Sérica/metabolismo , Albumina Sérica Glicada
6.
Int J Cardiol ; 220: 146-8, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27379916

RESUMO

BACKGROUND: Reperfusion injury offsets the beneficial effects of reperfusion therapy for ST-segment elevation myocardial infarction (STEMI). In our previous reports, postconditioning with lactate-enriched blood (PCLeB) induced excellent microcirculation recovery and less inflammation in STEMI patients. This study aimed to determine the in-hospital outcomes of STEMI patients treated using PCLeB. METHODS: Fifty-five consecutive STEMI patients were treated using PCLeB (Age 66.6±13.8years, 76.4% men) within 12h of symptom onset. In our modified postconditioning protocol, the duration of each brief reperfusion was prolonged from 10s to 60s in a stepwise manner. Lactated Ringer's solution (20-30mL) was injected directly into the culprit coronary artery at the end of each brief reperfusion and the balloon was quickly inflated at the lesion site, whereby lactate could be trapped inside the ischemic myocardium. Each brief ischemic period lasted 60s. After 7cycles of balloon inflation and deflation, full reperfusion was performed. Thereafter, stenting was performed and percutaneous coronary intervention (PCI) was completed. RESULTS: The mean corrected thrombolysis in myocardial infarction frame count was 20.1±10.1 after PCI completion. The mean peak serum creatine kinase and creatine kinase-MB levels were 2751±2227IU/L and 276±181IU/L respectively. None of the study patients died during their hospital stay or required continuation of oral diuretic or inotropic therapy for heart failure on discharge. CONCLUSIONS: PCLeB led to zero in-hospital mortality and no overt heart failure on discharge in 55 consecutive STEMI patients undergoing reperfusion therapy.


Assuntos
Angioplastia Coronária com Balão/métodos , Pós-Condicionamento Isquêmico/métodos , Soluções Isotônicas/administração & dosagem , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Reperfusão Miocárdica , Infarto do Miocárdio com Supradesnível do Segmento ST , Idoso , Fármacos Cardiovasculares/administração & dosagem , Vasos Coronários/patologia , Esquema de Medicação , Monitoramento de Medicamentos/métodos , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Reperfusão Miocárdica/efeitos adversos , Reperfusão Miocárdica/métodos , Traumatismo por Reperfusão Miocárdica/etiologia , Miocárdio/patologia , Avaliação de Processos e Resultados em Cuidados de Saúde , Lactato de Ringer , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Stents , Fatores de Tempo
7.
Phys Rev Lett ; 116(18): 181101, 2016 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-27203312

RESUMO

Extracting the unique information on ultradense nuclear matter from the gravitational waves emitted by merging neutron-star binaries requires robust theoretical models of the signal. We develop a novel effective-one-body waveform model that includes, for the first time, dynamic (instead of only adiabatic) tides of the neutron star as well as the merger signal for neutron-star-black-hole binaries. We demonstrate the importance of the dynamic tides by comparing our model against new numerical-relativity simulations of nonspinning neutron-star-black-hole binaries spanning more than 24 gravitational-wave cycles, and to other existing numerical simulations for double neutron-star systems. Furthermore, we derive an effective description that makes explicit the dependence of matter effects on two key parameters: tidal deformability and fundamental oscillation frequency.

8.
Am J Cardiol ; 115(12): 1636-42, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25891989

RESUMO

Previous models for contrast-induced acute kidney injury (CI-AKI) after percutaneous coronary intervention (PCI) include procedure-related variables in addition to pre-procedural variables. We sought to develop a risk model for CI-AKI based on pre-procedural variables and compare its predictability with a conventional risk model and also to develop an integer score system based on selected variables. A total of 5,936 consecutive PCIs registered in the Japanese Cardiovascular Database were analyzed (derivation cohort, n = 3,957; validation cohort, n = 1,979). CI-AKI was defined as an increase in serum creatinine of 50% or 0.3 mg/dl compared with baseline. From the derivation cohort, 2 different CI-AKI risk models were generated using logistic regression analyses: a pre-procedural model and a conventional model including both pre-procedural and procedure-related variables. The predictabilities of the models were compared by c-statistics. An integer score was assigned to each variable in proportion to each estimated regression coefficient for the final model. In our derivation cohort, the proportion of CI-AKI was 9.0% (n = 358). Predictors for CI-AKI included older age, heart failure, diabetes, previous PCI, hypertension, higher baseline creatinine level, and acute coronary syndrome. Presence of procedure-related complications and insertion of intra-aortic balloon pumping were included as procedure-related variables in the conventional model. Both the conventional model (c-statistics 0.789) and the pre-procedural model (c-statistics 0.799) demonstrated reasonable discrimination. The integer risk-scoring method demonstrated good agreement between the expected and observed risks of CI-AKI in the validation cohort. In conclusion, the pre-procedural risk model for CI-AKI had acceptable discrimination compared with the conventional model and may aid in risk stratification of CI-AKI before PCI.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Meios de Contraste/efeitos adversos , Modelos Teóricos , Intervenção Coronária Percutânea , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sistema de Registros , Medição de Risco , Fatores de Risco
10.
Methods Mol Biol ; 1153: 99-113, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24777792

RESUMO

Plastoquinones and phylloquinones are the major plant quinones localized in chloroplasts, and they act as photosynthetic electron redox mediators in thylakoid membranes. These quinones are analyzed by two processes: extraction with organic solvents and quinone assay by high-performance liquid chromatography (HPLC) analysis. Solvent choice is very important from the viewpoint of stability of the redox state in the extraction processes and during storage of plant quinones. We introduce procedures and solvents to avoid changes in the redox state of quinones, in addition to achieving high extraction efficiency. Traditional methods have problems of low sensitivity and require preparation steps to remove interfering substances, such as plant pigments. HPLC systems have been developed utilizing the fluorescent properties of quinols (reduced forms) to measure quinones. Plastoquinones were detected by reversed-phase HPLC with dual detectors (ultra-violet and fluorescence detection). However, the peak of phylloquinone and plastoquinone isomers with shorter side chains often overlaps with a large peak of fast-eluting pigments. To address these issues, HPLC with fluorescence detection after post-column reduction to convert quinones to fluorescent quinol was applied for measurement of fast-eluting quinones (low hydrophobicity quinones and quinols) such as phylloquinone. Using post-column reduction methods with sodium borohydride or platinum black, not only the reduced forms (fluorescent) but also the oxidized forms (non-fluorescent) could be clearly measured by HPLC with a fluorescence detector.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Fotossíntese , Quinonas/análise , Quinonas/isolamento & purificação , Oxirredução , Quinonas/química , Quinonas/metabolismo , Solventes/química , Espectrofotometria , Fatores de Tempo
13.
Biochem Biophys Res Commun ; 418(4): 811-7, 2012 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-22306819

RESUMO

Sir2 has been shown to be essential for transcriptional silencing and longevity provided by calorie restriction in Saccharomyces cerevisiae and Caenorhabditis elegans. In this study, we investigated the role for its mammalian homologue, SIRT1, in hematopoietic cells. SIRT1 inhibitor, nicotinamide (NA), promoted and its activator, resveratrol, inhibited the differentiation of murine bone marrow c-Kit(high)Sca-1(+)Lineage(-) (KSL) cells during the culture system ex vivo. To further clarify the roles of SIRT1 in hematopoietic cells, we isolated KSL cells from fetal liver of SIRT1 knockout (KO) mice and cultured them for 5days, because SIRT1 KO mice die shortly after the delivery. In agreement with the results from the experiments using NA and resveratrol, KSL cells isolated from SIRT1 KO mice more apparently differentiated and lost the KSL phenotype than those from wild-type (WT) mice. Furthermore, in each of colony assay, replating assay, or serial transplantation assay, SIRT1 KO KSL cells lost earlier the characteristics of stem cells than WT KSL cells. In addition, we found that SIRT1 maintains prematurity of hematopoietic cells through ROS elimination, FOXO activation, and p53 inhibition. These results suggest that SIRT1 suppresses differentiation of hematopoietic stem/progenitor cells and contributes to the maintenance of stem cell pool.


Assuntos
Diferenciação Celular , Células-Tronco Hematopoéticas/citologia , Sirtuína 1/fisiologia , Animais , Linhagem Celular , Técnicas de Inativação de Genes , Células-Tronco Hematopoéticas/enzimologia , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/enzimologia , Humanos , Camundongos , Sirtuína 1/genética
14.
Clin Appl Thromb Hemost ; 18(1): 66-71, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21733937

RESUMO

We have utilized high-dose factor VIII (FVIII) concentrates in 4 hemophilia A patients with inhibitors prior to surgery for the insertion of a central venous access device. In total, 3 patients out of 4 had high responding inhibitors. Dosing algorithms for this type of therapy have not been previously validated and established. We devised an effective formula to calculate the initial dose required to neutralize the inhibitors, although some of the patients demonstrated a lower recovery of FVIII than expected. An anamnestic inhibitor response was evident in 3 cases, but overall our strategy provided a reliable hemostatic effect for at least 4 days after surgery. In addition, our protocol appeared to be more cost-effective than FVIII bypass therapy. The financial saving in 1 case for the initial 3 days was estimated to be approximately US$49 122. Our results demonstrated that high-dose FVIII therapy provided clinically effective and economically viable results even in high responders.


Assuntos
Inibidores dos Fatores de Coagulação Sanguínea/sangue , Fator VIII/administração & dosagem , Hemofilia A/sangue , Hemofilia A/tratamento farmacológico , Hemostáticos/administração & dosagem , Criança , Pré-Escolar , Fator VIII/economia , Hemofilia A/economia , Hemostáticos/economia , Humanos , Lactente , Masculino
15.
Phys Rev Lett ; 107(21): 211101, 2011 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-22181867

RESUMO

Numerical simulations for the merger of binary neutron stars are performed in full general relativity incorporating both nucleonic and hyperonic finite-temperature equations of state (EOS) and neutrino cooling. It is found that even for the hyperonic EOS, a hypermassive neutron star is first formed after the merger for the typical total mass ≈2.7M(⊙), and subsequently collapses to a black hole (BH). It is shown that hyperons play a substantial role in the postmerger dynamics, torus formation around the BH, and emission of gravitational waves (GWs). In particular, the existence of hyperons is imprinted in GWs. Therefore, GW observations will provide a potential opportunity to explore the composition of neutron star matter.

16.
Phys Rev Lett ; 107(5): 051102, 2011 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-21867057

RESUMO

Numerical simulations for the merger of binary neutron stars are performed in full general relativity incorporating a finite-temperature (Shen's) equation of state (EOS) and neutrino cooling for the first time. It is found that for this stiff EOS, a hypermassive neutron star (HMNS) with a long lifetime (≫10 ms) is the outcome for the total mass ≲3.0M(⊙). It is shown that the typical total neutrino luminosity of the HMNS is ∼3-8×10(53) erg/s and the effective amplitude of gravitational waves from the HMNS is 4-6×10(-22) at f=2.1-2.5 kHz for a source distance of 100 Mpc. We also present the neutrino luminosity curve when a black hole is formed for the first time.

17.
Phys Rev Lett ; 106(25): 251102, 2011 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-21770625

RESUMO

Black hole (BH)-torus systems are promising candidates for the central engine of γ-ray bursts (GRBs), and also possible outcomes of the collapse of supermassive stars to supermassive black holes (SMBHs). By three-dimensional general relativistic numerical simulations, we show that an m = 1 nonaxisymmetric instability grows for a wide range of self-gravitating tori orbiting BHs. The resulting nonaxisymmetric structure persists for a time scale much longer than the dynamical one, becoming a strong emitter of large amplitude, quasiperiodic gravitational waves. Our results indicate that both, the central engine of GRBs and newly formed SMBHs, can be strong gravitational wave sources observable by forthcoming ground-based and spacecraft detectors.

18.
Leuk Res ; 35(9): 1205-11, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21440936

RESUMO

It would be of great value to predict the efficacy of tyrosine kinase inhibitors (TKIs) in the treatment of individual CML patients. We propose an immunoblot system for detecting the phosphorylation of Crkl, a major target of Bcr-Abl, in blood samples after in vitro incubation with TKIs. When the remaining phosphorylated Crkl after treatment with imatinib was evaluated as the "residual index (RI)", high values were found in accordance with imatinib resistance. Moreover, RI reflected the outcome of imatinib- as well as second generation TKIs with a high sensitivity and specificity. Therefore, this system should be useful in the selection of TKIs.


Assuntos
Proteínas de Fusão bcr-abl/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Quinases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Farmacológicos/análise , Biomarcadores Farmacológicos/metabolismo , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Células Cultivadas , Feminino , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/metabolismo , Fosforilação , Valor Preditivo dos Testes , Prognóstico , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/análise , Sensibilidade e Especificidade , Resultado do Tratamento , Adulto Jovem
19.
Plant Cell Environ ; 34(4): 618-28, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21251020

RESUMO

In order to ensure the cooperative function with the photosynthetic system, the mitochondrial respiratory chain needs to flexibly acclimate to a fluctuating light environment. The non-phosphorylating alternative oxidase (AOX) is a notable respiratory component that may support a cellular redox homeostasis under high-light (HL) conditions. Here we report the distinct acclimatory manner of the respiratory chain to long- and short-term HL conditions and the crucial function of AOX in Arabidopsis thaliana leaves. Plants grown under HL conditions (HL plants) possessed a larger ubiquinone (UQ) pool and a higher amount of cytochrome c oxidase than plants grown under low light conditions (LL plants). These responses in HL plants may be functional for efficient ATP production and sustain the fast plant growth. When LL plants were exposed to short-term HL stress (sHL), the UQ reduction level was transiently elevated. In the wild-type plant, the UQ pool was re-oxidized concomitantly with an up-regulation of AOX. On the other hand, the UQ reduction level of the AOX-deficient aox1a mutant remained high. Furthermore, the plastoquinone pool was also more reduced in the aox1a mutant under such conditions. These results suggest that AOX plays an important role in rapid acclimation of the respiratory chain to sHL, which may support efficient photosynthetic performance.


Assuntos
Arabidopsis/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Luz , Mitocôndrias/metabolismo , Oxirredutases/metabolismo , Aclimatação/genética , Arabidopsis/enzimologia , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transporte de Elétrons/genética , Transporte de Elétrons/fisiologia , Transporte de Elétrons/efeitos da radiação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Meio Ambiente , Regulação Enzimológica da Expressão Gênica/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Mitocôndrias/genética , Mitocôndrias/efeitos da radiação , Proteínas Mitocondriais , Mutagênese Insercional , Oxirredutases/genética , Fenótipo , Fotossíntese/genética , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Proteínas de Plantas , Fatores de Tempo , Ubiquinona , Regulação para Cima
20.
Living Rev Relativ ; 14(1): 6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-28163619

RESUMO

We review the current status of general relativistic studies for the coalescence of black hole-neutron star (BH-NS) binaries. First, procedures for a solution of BH-NS binaries in quasi-equilibrium circular orbits and the numerical results, such as quasi-equilibrium sequence and mass-shedding limit, of the high-precision computation, are summarized. Then, the current status of numerical-relativity simulations for the merger of BH-NS binaries is described. We summarize our understanding for the merger and/or tidal disruption processes, the criterion for tidal disruption, the properties of the remnant formed after the tidal disruption, gravitational waveform, and gravitational-wave spectrum.

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