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1.
Chem Pharm Bull (Tokyo) ; 71(9): 675-677, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37394629

RESUMO

We describe the photoinduced reductive debromination of phenacyl bromides using pyridoxal 5'-phosphate (PLP). The reaction requires irradiation with cyan or blue light in an anaerobic atmosphere. Mechanistic analysis reveals the formation of the phenacyl radical as an intermediate in the reaction, implying a single electron transfer to phenacyl bromides from a PLP-derived species resulting from excitation by illumination.


Assuntos
Brometos , Fosfato de Piridoxal , Fosfatos
2.
Angew Chem Int Ed Engl ; 62(13): e202217581, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36747340

RESUMO

All-solid-state batteries (ASSBs) with inorganic solid electrolytes (SEs) have attracted significant interest as next-generation energy storage. Halides such as Li3 YCl6 are promising candidates for SE because they combine high oxidation stability and deformability. However, the ionic conductivities of halide SEs are not as high as those of other SEs, especially sulfides. Here, we discover new lithium-metal-oxy-halide materials, LiMOCl4 (M=Nb, Ta). They exhibit extremely high ionic conductivities of 10.4 mS cm-1 for M=Nb and 12.4 mS cm-1 for M=Ta, respectively, even in cold-pressed powder forms at room temperature, which are comparable to or surpass those of organic liquid electrolytes used in lithium-ion batteries. Bulk-type ASSB cells using the oxyhalides as the cathode SE demonstrate an outstanding rate capability with a capacity retention of 80 % at 5 C/0.1 C. We believe that the proposed oxyhalides are promising SE candidates for the practical applications of ASSBs.

3.
Development ; 149(11)2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35485417

RESUMO

The root cap is a multilayered tissue covering the tip of a plant root that directs root growth through its unique functions, such as gravity sensing and rhizosphere interaction. To maintain the structure and function of the root cap, its constituent cells are constantly turned over through balanced cell division and cell detachment in the inner and outer cell layers, respectively. Upon displacement toward the outermost layer, columella cells at the central root cap domain functionally transition from gravity-sensing cells to secretory cells, but the mechanisms underlying this drastic cell fate transition are largely unknown. Here, using live-cell tracking microscopy, we show that organelles in the outermost cell layer undergo dramatic rearrangements. This rearrangement depends, at least partially, on spatiotemporally regulated activation of autophagy. Notably, this root cap autophagy does not lead to immediate cell death, but is instead necessary for organized separation of living root cap cells, highlighting a previously undescribed role of developmentally regulated autophagy in plants. This article has an associated 'The people behind the papers' interview.


Assuntos
Arabidopsis , Arabidopsis/metabolismo , Autofagia , Separação Celular , Humanos , Organelas , Coifa , Raízes de Plantas/metabolismo
4.
J Appl Clin Med Phys ; 20(7): 48-57, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31237090

RESUMO

To improve the penumbra of low-energy beams used in spot-scanning proton therapy, various collimation systems have been proposed and used in clinics. In this paper, focused on patient-specific brass collimators, the collimator-scattered protons' physical and biological effects were investigated. The Geant4 Monte Carlo code was used to model the collimators mounted on the scanning nozzle of the Hokkaido University Hospital. A systematic survey was performed in water phantom with various-sized rectangular targets; range (5-20 cm), spread-out Bragg peak (SOBP) (5-10 cm), and field size (2 × 2-16 × 16 cm2 ). It revealed that both the range and SOBP dependences of the physical dose increase had similar trends to passive scattering methods, that is, it increased largely with the range and slightly with the SOBP. The physical impact was maximized at the surface (3%-22% for the tested geometries) and decreased with depth. In contrast, the field size (FS) dependence differed from that observed in passive scattering: the increase was high for both small and large FSs. This may be attributed to the different phase-space shapes at the target boundary between the two dose delivery methods. Next, the biological impact was estimated based on the increase in dose-averaged linear energy transfer (LETd ) and relative biological effectiveness (RBE). The LETd of the collimator-scattered protons were several keV/µm higher than that of unscattered ones; however, since this large increase was observed only at the positions receiving a small scattered dose, the overall LETd increase was negligible. As a consequence, the RBE increase did not exceed 0.05. Finally, the effects on patient geometries were estimated by testing two patient plans, and a negligible RBE increase (0.9% at most in the critical organs at surface) was observed in both cases. Therefore, the impact of collimator-scattered protons is almost entirely attributed to the physical dose increase, while the RBE increase is negligible.


Assuntos
Algoritmos , Melanoma/radioterapia , Terapia com Prótons/instrumentação , Terapia com Prótons/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Rabdomiossarcoma/radioterapia , Neoplasias Uveais/radioterapia , Criança , Simulação por Computador , Relação Dose-Resposta à Radiação , Humanos , Método de Monte Carlo , Órgãos em Risco/efeitos da radiação , Eficiência Biológica Relativa , Espalhamento de Radiação
5.
J Am Soc Nephrol ; 16(12): 3742-7, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16251241

RESUMO

Uremic pruritus is a very common and frustrating condition for both patients and clinicians because no treatment has been demonstrated to be effective in relieving the itch. In this report, nalfurafine, a new kappa-opioid receptor agonist, was used to treat uremic pruritus in patients who were undergoing routine hemodialysis. Two multicenter, randomized, double-blind, placebo-controlled studies enrolled 144 patients with uremic pruritus to postdialysis intravenous treatment with either nalfurafine or placebo for 2 to 4 wk. A meta-analysis approach was used to assess the efficacy of nalfurafine. Statistically significant reductions in worst itching (P = 0.0212), itching intensity (P = 0.0410), and sleep disturbances (P = 0.0003) were noted in the nalfurafine group as compared with placebo. Improvements in itching (P = 0.0025) and excoriations (P = 0.0060) were noted for the nalfurafine-treated patients. Nalfurafine showed similar types and incidences of drug-related adverse events as did placebo. Nalfurafine was shown to be an effective and safe compound for use in this severely ill patient population.


Assuntos
Antipruriginosos/uso terapêutico , Naltrexona/uso terapêutico , Prurido/tratamento farmacológico , Prurido/etiologia , Receptores Opioides kappa/antagonistas & inibidores , Uremia/complicações , Adulto , Idoso , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Seguimentos , Humanos , Infusões Intravenosas , Falência Renal Crônica/complicações , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/terapia , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Probabilidade , Prurido/fisiopatologia , Valores de Referência , Diálise Renal , Medição de Risco , Índice de Gravidade de Doença , Resultado do Tratamento , Uremia/diagnóstico , Uremia/terapia
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