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1.
Phys Rev Lett ; 130(17): 173001, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37172243

RESUMO

To test bound-state quantum electrodynamics (BSQED) in the strong-field regime, we have performed high precision x-ray spectroscopy of the 5g-4f and 5f- 4d transitions (BSQED contribution of 2.4 and 5.2 eV, respectively) of muonic neon atoms in the low-pressure gas phase without bound electrons. Muonic atoms have been recently proposed as an alternative to few-electron high-Z ions for BSQED tests by focusing on circular Rydberg states where nuclear contributions are negligibly small. We determined the 5g_{9/2}- 4f_{7/2} transition energy to be 6297.08±0.04(stat)±0.13(syst) eV using superconducting transition-edge sensor microcalorimeters (5.2-5.5 eV FWHM resolution), which agrees well with the most advanced BSQED theoretical prediction of 6297.26 eV.

2.
Osteoporos Int ; 34(7): 1207-1221, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37067545

RESUMO

This study investigated the long-term survival and incidence of secondary fractures after fragility hip fractures. The 5-year survival rate was 62%, and the mortality risk was seen in patients with GNRI < 92. The 5-year incidence of secondary fracture was 22%, which was significantly higher in patients with a BMI < 20. BACKGROUND: Malnutrition negatively influences the postoperative survival of patients with fragility hip fractures (FHFs); however, little is known about their association over the long term. OBJECTIVE: This study evaluated the ability of the geriatric nutritional risk index (GNRI) as a risk factor for long-term mortality after FHFs. METHODS: This study included 623 Japanese patients with FHFs over the age of 60 years. We prospectively collected data on admission and during hospitalization and assessed the patients' conditions after discharge through a questionnaire. We examined the long-term mortality and the incidence of secondary FHFs and assessed the prognostic factors. RESULTS: The mean observation period was 4.0 years (range 0-7 years). The average age at the time of admission was 82 years (range 60-101 years). The overall survival after FHFs (1 year, 91%; 5 years, 62%) and the incidence of secondary FHFs were high (1 year, 4%; 5 years, 22%). The multivariate Cox proportional hazard analysis revealed the risk factors for mortality as older age (hazard ratio [HR] 1.04), male sex (HR 1.96), lower GNRI score (HR 0.96), comorbidities (malignancy, HR 2.51; ischemic heart disease, HR 2.24; revised Hasegawa dementia scale ≤ 20, HR 1.64), no use of active vitamin D3 on admission (HR 0.46), and a lower Barthel index (BI) (on admission, HR 1.00; at discharge, HR 0.99). The GNRI scores were divided into four risk categories: major risk (GNRI, < 82), moderate risk (82-91), low risk (92-98), and no risk (> 98). Patients at major and moderate risks of GNRI had a significantly lower overall survival rate (p < 0.001). Lower body mass index (BMI) was also identified as a prognostic factor for secondary FHFs (HR 0.88 [p = 0.004]). CONCLUSIONS: We showed that older age, male sex, a lower GNRI score, comorbidities, and a lower BI are risk factors for mortality following FHFs. GNRI is a novel and simple predictor of long-term survival after FHFs.


Assuntos
Fraturas do Quadril , Desnutrição , Humanos , Masculino , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Avaliação Nutricional , Prognóstico , Desnutrição/complicações , Desnutrição/epidemiologia , Fraturas do Quadril/etiologia , Fatores de Risco , Avaliação Geriátrica , Estado Nutricional , Estudos Retrospectivos
3.
Science ; 379(6634): eabn8671, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36137011

RESUMO

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

4.
Phys Rev Lett ; 127(5): 053001, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34397250

RESUMO

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kß x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.

5.
Sci Rep ; 7(1): 15478, 2017 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-29133830

RESUMO

Electron- or X-ray-induced characteristic X-ray analysis has been widely used to determine chemical compositions of materials in vast research fields. In recent years, analysis of characteristic X-rays from muonic atoms, in which a muon is captured, has attracted attention because both a muon beam and a muon-induced characteristic X-ray have high transmission abilities. Here we report the first non-destructive elemental analysis of a carbonaceous chondrite using one of the world-leading intense direct current muon beam source (MuSIC; MUon Science Innovative Channel). We successfully detected characteristic muonic X-rays of Mg, Si, Fe, O, S and C from Jbilet Winselwan CM chondrite, of which carbon content is about 2 wt%, and the obtained elemental abundance pattern was consistent with that of CM chondrites. Because of its high sensitivity to carbon, non-destructive elemental analysis with a muon beam can be a novel powerful tool to characterize future retuned samples from carbonaceous asteroids.

6.
Am J Transplant ; 16(9): 2574-88, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26932231

RESUMO

Fibrosis is a major component of chronic cardiac allograft rejection. Although several cell types are able to produce collagen, resident (donor-derived) fibroblasts are mainly responsible for excessive production of extracellular matrix proteins. It is currently unclear which cells regulate production of connective tissue elements in allograft fibrosis and how basophils, as potential producers of profibrotic cytokines, are involved this process. We studied this question in a fully MHC-mismatched model of heart transplantation with transient depletion of CD4(+) T cells to largely prevent acute rejection. The model is characterized by myocardial infiltration of leukocytes and development of interstitial fibrosis and allograft vasculopathy. Using depletion of basophils, IL-4-deficient recipients and IL-4 receptor-deficient grafts, we showed that basophils and IL-4 play crucial roles in activation of fibroblasts and development of fibrotic organ remodeling. In the absence of CD4(+) T cells, basophils are the predominant source of IL-4 in the graft and contribute to expansion of myofibroblasts, interstitial deposition of collagen and development of allograft vasculopathy. Our results indicated that basophils trigger the production of various connective tissue elements by myofibroblasts. Basophil-derived IL-4 may be an attractive target for treatment of chronic allograft rejection.


Assuntos
Basófilos/imunologia , Rejeição de Enxerto/etiologia , Cardiopatias/etiologia , Transplante de Coração/efeitos adversos , Interleucina-4/fisiologia , Aloenxertos , Animais , Feminino , Fibrose/etiologia , Fibrose/patologia , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto , Cardiopatias/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout
7.
J Fish Biol ; 86(1): 409-15, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25430054

RESUMO

Diel drift patterns of larvae of the endangered cyprinid Gnathopogon caerelescens in an inlet of the Ibanaiko Lagoon, connected to Lake Biwa in Japan, were assessed in April 2012. Peak occurrence of yolk-sac larvae was within a few hours after dark. Drift of newly hatched larvae is considered to be an important biological mechanism that ensures larval dispersal and recruitment from the inlets (spawning grounds) to the lagoon which functions as a nursery ground.


Assuntos
Distribuição Animal , Cyprinidae , Animais , Baías , Japão , Lagos , Larva , Periodicidade
8.
Sci Rep ; 4: 5072, 2014 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-24861282

RESUMO

The recent development of the intense pulsed muon source at J-PARC MUSE, Japan Proton Accelerator Research Complex/MUon Science Establishment (10(6) s(-1) for a momentum of 60 MeV/c), enabled us to pioneer a new frontier in analytical sciences. Here, we report a non-destructive elemental analysis using µ(-) capture. Controlling muon momentum from 32.5 to 57.5 MeV/c, we successfully demonstrate a depth-profile analysis of light elements (B, C, N, and O) from several mm-thick layered materials and non-destructive bulk analyses of meteorites containing organic materials. Muon beam analysis, enabling a bulk analysis of light to heavy elements without severe radioactivation, is a unique analytical method complementary to other non-destructive analyses. Furthermore, this technology can be used as a powerful tool to identify the content and distribution of organic components in future asteroidal return samples.

9.
Radiat Prot Dosimetry ; 161(1-4): 139-43, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24368868

RESUMO

Neutron activation cross sections for Bi and Co at 386 MeV were measured by activation method. A quasi-monoenergetic neutron beam was produced using the (7)Li(p,n) reaction. The energy spectrum of these neutrons has a high-energy peak (386 MeV) and a low-energy tail. Two neutron beams, 0° and 25° from the proton beam axis, were used for sample irradiation, enabling a correction for the contribution of the low-energy neutrons. The neutron-induced activation cross sections were estimated by subtracting the reaction rates of irradiated samples for 25° irradiation from those of 0° irradiation. The measured cross sections were compared with the findings of other studies, evaluated in relation to nuclear data files and the calculated data by Particle and Heavy Ion Transport code System code.


Assuntos
Bismuto/química , Cobalto/química , Nêutrons , Aceleradores de Partículas , Radiometria/instrumentação , Radiometria/métodos , Íons Pesados , Prótons , Doses de Radiação , Radioisótopos/química , Reprodutibilidade dos Testes
11.
Oncogene ; 31(37): 4128-38, 2012 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-22158033

RESUMO

The membrane-anchored matrix metalloproteinase-regulator RECK is often downregulated in cancers; in some cases, a significant correlation between the level of residual RECK in resected tumors and patient survival has been noted. Furthermore, restoration of RECK expression in certain cancer-derived cell lines results in reduced tumorigenicity. Here we report that acute RECK expression in colon carcinoma cells results in cell cycle-arrest accompanied by downregulation of a ubiquitin ligase component, S-phase kinase-associated protein 2 (SKP2), and upregulation of its substrate, p27(KIP1). Our data indicate that RECK-induced growth suppression is at least partially dependent on p27, and that RECK and type I collagen share similar effects on the SKP2-p27 pathway. Importantly, in patients with lung, colorectal and bladder cancers, the RECK/SKP2 ratio is high in normal tissues and lower in the cancer tissues. These findings reveal a novel molecular pathway linking cell-cycle progression to RECK downregulation, extracellular matrix degradation and SKP2 upregulation, and suggest that treatment regimens that induce RECK expression could be promising cancer therapies.


Assuntos
Neoplasias do Colo/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Proteínas Ligadas por GPI/metabolismo , Proteínas Quinases Associadas a Fase S/biossíntese , Animais , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Colo/patologia , Regulação para Baixo , Proteínas Ligadas por GPI/genética , Humanos , Camundongos , Células NIH 3T3 , Fosforilação , Interferência de RNA , RNA Interferente Pequeno , Regulação para Cima
15.
Eur Respir J ; 20(5): 1213-9, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12449176

RESUMO

This study was performed to find the rationale for administering steroids to patients with idiopathic interstitial pneumonia (IIP), which was unlikely to be usual interstitial pneumonia (UIP) but was not surgically biopsied. Among IIP patients in the file of the departments, nine patients who met the following criteria were selected for this study ("non-UIP" group): 1) transbronchial lung biopsy showed dense mononuclear cell infiltration in thickened alveolar septa; 2) chest radiograph and computed tomography showed irregular linear, reticular or ground-glass opacities with alveolar consolidation without honeycombing in the lung base; and 3) spirometry was performed before and after steroid therapy. Ten patients with pathologically confirmed nonspecific interstitial pneumonia ("NSIP" group) were also selected for the comparison. Baseline values and percentage increase of vital capacity (VC) after steroid therapy were plotted. Steroids improved VC in both groups of patients. After 1 yr of steroid therapy, percentage increase of VC in "non-UIP" was 28.8+/-7.7%, which was not significantly different from that in NSIP (30.0+/-11.7%). One "non-UIP" patient and one NSIP patient died after 6.4 and 4.3 yrs of follow-up, respectively. Patients with idiopathic interstitial pneumonia presenting cellular interstitial pneumonia in transbronchial lung biopsy, in addition to radiographic findings not typical for usual interstitial pneumonia, could expect a beneficial effect of steroids without undergoing surgical biopsy.


Assuntos
Glucocorticoides/uso terapêutico , Doenças Pulmonares Intersticiais/tratamento farmacológico , Pulmão/patologia , Idoso , Biópsia por Agulha , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/diagnóstico por imagem , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Doenças Pulmonares Intersticiais/patologia , Doenças Pulmonares Intersticiais/fisiopatologia , Masculino , Pessoa de Meia-Idade , Capacidade de Difusão Pulmonar , Radiografia Torácica , Tomografia Computadorizada por Raios X , Capacidade Pulmonar Total , Capacidade Vital
16.
Surg Endosc ; 16(8): 1220-5, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11984669

RESUMO

BACKGROUND: The aim of our study was to investigate the effect of carbon dioxide pneumoperitoneum on systemic and splanchnic hemodynamics in cirrhotic rats. METHODS: Sprague-Dawley rats (n = 80) were used in this study. Liver cirrhosis was induced by thioacetamide administration intraperitoneally (200 mg/kg body weight, twice a week for 16 weeks). The radioactive microsphere method was used to measure systemic and regional hemodynamic parameters before, 1 h after the start, and 1 h after the release of pneumoperitoneum. RESULTS: Splanchnic blood flow and cardiac index were significantly depressed during pneumoperitoneum in liver cirrhosis and control groups, but no significant differences were seen between the two groups. In both groups, portal venous inflow decreased and hepatic arterial blood flow increased significantly during pneumoperitoneum. However, during pneumoperitoneum, total hepatic blood flow as a percentage of its value before pneumoperitoneum was lower in cirrhotic rats (71.0%) than in control rats (91.9%) (p <0.05, Mann-Whitney U-test). CONCLUSIONS: Carbon dioxide pneumoperitoneum markedly decreases total hepatic blood flow in cirrhotic rats due to the impaired hepatic arterial buffer response. Liver function should be carefully controlled in cirrhotic patients after laparoscopic surgery with pneumoperitoneum.


Assuntos
Hemodinâmica , Laparoscopia/efeitos adversos , Cirrose Hepática/fisiopatologia , Cirrose Hepática/terapia , Fígado/irrigação sanguínea , Pneumoperitônio Artificial/efeitos adversos , Animais , Pressão Sanguínea , Dióxido de Carbono , Frequência Cardíaca , Cirrose Hepática/induzido quimicamente , Masculino , Veia Porta/fisiopatologia , Ratos , Ratos Endogâmicos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional , Circulação Esplâncnica , Tioacetamida
17.
Chem Pharm Bull (Tokyo) ; 49(8): 1003-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11515568

RESUMO

A new ionone glucoside, pisumionoside, a phenethyl glycoside, sayaendoside, and two acylated flavonol oligoglycosides, pisumflavonosides I and II, were isolated from the young seedpods of garden peas, Pisum sativum L., together with quercetin and kaempferol 3-O-(6-O-trans-p-coumaroyl)-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosides and quercetin and kaempferol 3-sophorotriosides. The structures of pisumionoside, sayaendoside, and pisumflavonosides I and II were determined on the basis of chemical and physicochemical evidence, respectively. Quercetin 3-sophorotrioside, a principle component, was found to show protective effects on liver injury induced by D-galactosamine and lipopolysaccharide and by carbon tetrachloride in mice.


Assuntos
Flavanonas , Flavonoides/farmacologia , Glucosídeos/farmacologia , Glicosídeos/farmacologia , Hepatócitos/efeitos dos fármacos , Plantas Medicinais/química , Animais , Tetracloreto de Carbono/toxicidade , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas , Flavonoides/administração & dosagem , Flavonoides/química , Galactosamina/toxicidade , Glucosídeos/administração & dosagem , Glucosídeos/química , Glicosídeos/administração & dosagem , Glicosídeos/química , Hepatócitos/patologia , Injeções Intraperitoneais , Lipopolissacarídeos/toxicidade , Hepatopatias/prevenção & controle , Masculino , Camundongos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sementes/química
18.
Eur Surg Res ; 33(2): 71-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11399871

RESUMO

We studied the effect of carbon dioxide (CO2) pneumoperitoneum on the systemic and peritoneal cytokine response in a rat model of intraperitoneal sepsis. After intraperitoneal injection of bacterial lipopolysaccharide (LPS, 10 mg/kg), rats were divided into 3 groups (n = 49 in each group): control (abdominal puncture); CO2 pneumoperitoneum, and laparotomy. Blood and peritoneal lavage fluid (PLF) were sampled at 0, 1, 2, 3, 4, 6, and 8 h after LPS challenge. Blood cell counts, plasma endotoxin level, and the levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-6 (IL-6) in the plasma and PLF were measured. Blood cell counts did not differ between the 3 groups. Plasma endotoxin levels in the pneumoperitoneum group were significantly increased immediately after the procedure (p < 0.05). Although peak plasma TNF-alpha levels in the pneumoperitoneum group were seen immediately after the procedure, other changes in plasma cytokine levels did not differ significantly between the 3 groups. PLF TNF-alpha and IL-1beta levels in the pneumoperitoneum group were significantly lower than levels in the control and laparotomy groups soon after the procedure (p < 0.05). PLF IL-6 levels in the pneumoperitoneum group tended to be lower than those in the laparotomy group. In conclusion, CO2 pneumoperitoneum might induce different responses between systemic and peritoneal cytokines soon after the procedure in a rat model of intraperitoneal sepsis.


Assuntos
Citocinas/metabolismo , Infecções/metabolismo , Doenças Peritoneais/metabolismo , Peritônio/metabolismo , Pneumoperitônio Artificial , Animais , Dióxido de Carbono , Citocinas/sangue , Endotoxinas/sangue , Infecções/induzido quimicamente , Mediadores da Inflamação/sangue , Lipopolissacarídeos , Masculino , Ratos , Ratos Sprague-Dawley , Irrigação Terapêutica
19.
Bioorg Med Chem ; 9(4): 909-16, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11354673

RESUMO

New carabrane-type sesquiterpene lactones, curcumenolactones A, B, and C, were isolated from the 80% aqueous acetone extract of Zedoariae Rhizoma (Zingiberaceae), together with 41 sesquiterpenes and two diarylheptanoids. The absolute stereostructures of curcumenolactones A, B, and C were determined on the basis of physicochemical evidence, which included nuclear Overhauser effect (NOE) and circular dichroic (CD) spectroscopic analyses. Curcumenone, a principal carabrane-type sesquiterpene from Zedoariae Rhizoma, was found to show potent protective effect on D-galactosamine/lipopolysaccharide-induced acute liver injury in mice. In addition, curcumenolactones A and B and the other constituents showed protective effect on D-galactosamine-induced cytotoxicity in primary cultured rat hepatocytes.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Lactonas/farmacologia , Plantas Medicinais/química , Sesquiterpenos/farmacologia , Animais , Relação Dose-Resposta a Droga , Galactosamina/antagonistas & inibidores , Galactosamina/toxicidade , Hepatócitos/efeitos dos fármacos , Lactonas/química , Lactonas/isolamento & purificação , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/toxicidade , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Ratos , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Espectrofotometria Ultravioleta
20.
Nucleic Acids Res Suppl ; (1): 179-80, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12836323

RESUMO

The interaction of antisense peptide nucleic acid (PNA) with yeast tRNA(Phe) was investigated. A 6-mer PNA complementary to the 3'-terminal sequence including the 73ACCA end hybridized to the tRNA. While the PNA with a single mismatch did not. PNA is a promising candidate for controlling tRNA functions by the sequence-specific hybridization.


Assuntos
Elementos Antissenso (Genética)/química , Ácidos Nucleicos Peptídicos/química , RNA de Transferência/química , Aminoacil-tRNA Sintetases/química , Elementos Antissenso (Genética)/farmacologia , Sequência de Bases , Hibridização de Ácido Nucleico , Ácidos Nucleicos Peptídicos/farmacologia , RNA de Transferência/fisiologia
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