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1.
Rev Sci Instrum ; 95(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38990080

RESUMO

We developed a near-infrared focused heating system (IRrDAC) for deformation experiments using a rotational diamond anvil cell. This study reports the results of annealing tests on silver and antigorite conducted at SPring-8 (BL47XU) using the IRrDAC system. The experimental results demonstrated the melting of silver and the dehydration of antigorite, confirming the capability of this system. The reproducible relationships between temperature and input power were also confirmed. The IRrDAC system enables deformation experiments at pressures equivalent to those of the lower mantle under homogeneous and stable temperatures and is expected to contribute to the understanding of deep Earth rheology.

2.
Phys Rev Lett ; 130(26): 266301, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37450814

RESUMO

We determined the electrical resistivity of liquid Fe to 135 GPa and 6680 K using a four-probe method in a diamond-anvil cell combined with two novel techniques: (i) enclosing a molten Fe in a sapphire capsule, and (ii) millisecond time-resolved simultaneous measurements of the resistance, x-ray diffraction, and temperature of instantaneously melted Fe. Our results show the minimal temperature dependence of the resistivity of liquid Fe and its anomalous resistivity decrease around 50 GPa, likely associated with a gradual magnetic transition, both in agreement with previous ab initio calculations.


Assuntos
Diamante , Eletricidade , Ferro , Temperatura , Difração de Raios X
3.
BMC Cancer ; 22(1): 912, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35999529

RESUMO

BACKGROUND: Lenvatinib is appropriate for reducing the production of nitric oxide (NO) and facilitating as block angiogenesis. However, to our knowledge, there are no data that support the correlation between NO and clinical response in patients who received lenvatinib therapy for HCC. Therefore, we investigated the correlation between the change rate of NO levels and clinical responses including adverse events (AEs) after lenvatinib therapy for unresectable hepatocellular carcinoma (HCC). METHODS: This study was conducted using previously collected data from another study. We enrolled 70 patients who received lenvatinib for advanced or unresectable HCC. NO was measured by converting nitrate (NO3-) to nitrite (NO2-) with nitrate reductase, followed by quantitation of NO2- based on Griess reagent. To determine whether lenvatinib influences NO in unresectable HCC, we evaluated the influence of the change rate of NO from baseline after administration of lenvatinib on maximal therapeutic response and SAE. RESULTS: After lenvatinib administration, a change rate in the NO from 0.27 to 4.16 was observed. There was no difference between the clinical response to lenvatinib and the change rate of NO (p = 0.632). However, the change rate of NO was significantly lower in patients with AEs than in those without AEs (p = 0.030). When a reduction in NO rate of < 0.8 was defined as a clinically significant reduction of NO (CSRN), the CSRN group had significantly worse progression-free survival (PFS) and overall survival (OS) than the non-CSRN group (p = 0.029 and p = 0.005, respectively). CONCLUSION: Decreased NO levels were associated with the occurrence of AEs and worse prognosis after lenvatinib administration. Change rate in serum NO can be used as predictive markers in patients receiving lenvatinib therapy for HCC.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Quinolinas , Antineoplásicos/efeitos adversos , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/patologia , Óxido Nítrico , Dióxido de Nitrogênio/uso terapêutico , Compostos de Fenilureia/efeitos adversos , Quinolinas/efeitos adversos
4.
J Infect Chemother ; 28(7): 884-889, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35331613

RESUMO

INTRODUCTION: Microorganisms can evolve and become resistant to antimicrobials, and this is known as antimicrobial resistance (AMR). Inappropriate use of antibiotics contributes to AMR, and antimicrobial stewardship programs have been developed to mitigate AMR. The Appropriate Use of Carbapenems Program was implemented in March 2019 in a university hospital and its effect was evaluated. METHODS: We conducted a prospective audit and feedback on carbapenems at the time of prescription daily. Additionally, we compared a monthly survey of the total days of therapy (DOTs) per 1000 patient-days for carbapenems, piperacillin/tazobactam, and fluoroquinolones. The susceptibility of Pseudomonas aeruginosa to meropenem, piperacillin/tazobactam, and levofloxacin was tested before (January 2018 to February 2019) and after (March 2019 to December 2020) the intervention. RESULTS: The monthly median DOTs of carbapenem usage decreased after the intervention; carbapenem use immediately declined during the intervention period. The monthly median DOTs of piperacillin/tazobactam and fluoroquinolones also decreased and continued to decline significantly after the intervention. Susceptibility of P. aeruginosa to meropenem, piperacillin/tazobactam, and levofloxacin did not change significantly during the study. CONCLUSION: The implementation of the Appropriate Use of Carbapenems Program was effective in reducing the use of broad-spectrum antibiotics and maintaining the antibiotic susceptibility of P. aeruginosa.


Assuntos
Gestão de Antimicrobianos , Carbapenêmicos , Antibacterianos/uso terapêutico , Carbapenêmicos/uso terapêutico , Fluoroquinolonas/uso terapêutico , Hospitais , Humanos , Japão , Levofloxacino/uso terapêutico , Meropeném/uso terapêutico , Combinação Piperacilina e Tazobactam/uso terapêutico , Pseudomonas aeruginosa
6.
Sci Rep ; 10(1): 17054, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051476

RESUMO

We investigated whether or not nitric oxide synthase 3 (NOS3) rs2070744 genotypes can affect the response for lenvatinib treatment in patients with hepatocellular carcinoma (HCC). We evaluated the relation of the NOS3 rs2070744 genotypes to the tumor response, progression-free survival (PFS), and overall survival (OS) as the response for lenvatinib. We also examined the association between fibroblast growth factor receptor (FGFR) gene polymorphisms, a potential feature of lenvatinib, and the response. There were no significant differences between the studies for either PFS or OS, even though patients with the TT genotype had a longer mean PFS (hazard ratio [HR] 0.60; p = 0.069) and mean OS (HR 0.46; p = 0.075) than those with the TC/CC genotypes. However, patients with a single-nucleotide polymorphism (SNP) combination pattern of the NOS3 rs2070744 TC/CC and FGFR4 rs351855 CT/TT genotypes had a significantly shorter mean PFS (HR 2.56; p = 0.006) and mean OS (HR 3.36; p = 0.013) than those with the other genotypes. The NOS3 rs2070744 genotypes did not influence the clinical response. However, the SNP combination pattern of the NOS3 rs2070744 and FGFR4 rs351855 genotypes may be helpful as treatment effect predictors and prognostic factors for HCC patients treated with lenvatinib.


Assuntos
Carcinoma Hepatocelular/genética , Óxido Nítrico Sintase Tipo III/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Farmacológicos , Carcinoma Hepatocelular/tratamento farmacológico , Intervalo Livre de Doença , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo III/metabolismo , Compostos de Fenilureia/farmacologia , Polimorfismo de Nucleotídeo Único/genética , Prognóstico , Quinolinas/farmacologia , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/análise , Receptores de Fatores de Crescimento de Fibroblastos/genética
7.
Rev Sci Instrum ; 88(4): 044501, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28456273

RESUMO

A large-strain, torsional deformation apparatus has been developed based on diamond anvil cells at high pressures, up to 135 GPa with a help of hard nano-polycrystalline diamond anvils. These pressure conditions correspond to the base of the Earth's mantle. An X-ray laminography technique is introduced for high-pressure in situ 3D observations of the strain markers. The technique developed in this study introduces the possibility of the in situ rheological measurements of the deep Earth materials under ultrahigh-pressure conditions.

8.
Sci Rep ; 4: 4403, 2014 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-24638113

RESUMO

Plate tectonics is largely responsible for material and heat circulation in Earth, but for unknown reasons it does not exist on Venus. The strength of planetary materials is a key control on plate tectonics because physical properties, such as temperature, pressure, stress, and chemical composition, result in strong rheological layering and convection in planetary interiors. Our deformation experiments show that crustal plagioclase is much weaker than mantle olivine at conditions corresponding to the Moho in Venus. Consequently, this strength contrast may produce a mechanical decoupling between the Venusian crust and interior mantle convection. One-dimensional numerical modeling using our experimental data confirms that this large strength contrast at the Moho impedes the surface motion of the Venusian crust and, as such, is an important factor in explaining the absence of plate tectonics on Venus.

9.
Chemistry ; 17(3): 855-65, 2011 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-21226100

RESUMO

Porphyrin-based supramolecular nanostructures have been produced by the self-assembly of porphyrin macrorings with three benzoic acid groups (Acid-R) on each side of the rings through cooperative carboxyl-carboxyl hydrogen bonds. Structures of the organized Acid-R were analyzed by AFM, and two clear distribution peaks were observed at 3 and 27 nm in the height-distribution histogram. From the overall assessment, the higher objects are considered to be one-dimensional structures standing vertically on the mica substrate. The height corresponds to an 11-mer of a unit Acid-R. Light-harvesting functions were examined by using fluorescence titration, whereby an energy-acceptor molecule (Tripod 2) was employed that strongly interacted with Acid-R units (association constant: 2.0×10(8) M(-1) ), specifically from the inner pore. The titration results showed that the apparent stoichiometry [Tripod 2]/[Acid-R] was <0.5, and that the value was concentration dependent. Titration results reasonably account for the scheme in which Tripod 2 only interacts with each terminal in the organized Acid-R. The number of organization was fitted to a 10-mer of Acid-R in a 6.8×10(-7) M solution, and was consistent with that estimated from the AFM results. In the composites of organized Acid-R/Tripod 2, a singlet excitation energy transfer occurred among the Acid-R units, and to Tripod 2. The energy-transfer rate constants were estimated by using the decamer model, which employed kinetic parameters obtained from steady-state and time-resolved fluorescence experiments.

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