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1.
Nature ; 615(7954): 854-857, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36922597

RESUMO

The timing of delivery and the types of body that contributed volatiles to the terrestrial planets remain highly debated1,2. For example, it is unknown if differentiated bodies, such as that responsible for the Moon-forming giant impact, could have delivered substantial volatiles3,4 or if smaller, undifferentiated objects were more probable vehicles of water delivery5-7. Here we show that the water contents of minerals in achondrite meteorites (mantles or crusts of differentiated planetesimals) from both the inner and outer portions of the early Solar System are ≤2 µg g-1 H2O. These are among the lowest values ever reported for extraterrestrial minerals. Our results demonstrate that differentiated planetesimals efficiently degassed before or during melting. This finding implies that substantial amounts of water could only have been delivered to Earth by means of unmelted material.

2.
Phys Rev Lett ; 132(24): 241803, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38949341

RESUMO

We report a search for time variations of the solar ^{8}B neutrino flux using 5804 live days of Super-Kamiokande data collected between May 31, 1996, and May 30, 2018. Super-Kamiokande measured the precise time of each solar neutrino interaction over 22 calendar years to search for solar neutrino flux modulations with unprecedented precision. Periodic modulations are searched for in a dataset comprising five-day interval solar neutrino flux measurements with a maximum likelihood method. We also applied the Lomb-Scargle method to this dataset to compare it with previous reports. The only significant modulation found is due to the elliptic orbit of the Earth around the Sun. The observed modulation is consistent with astronomical data: we measured an eccentricity of (1.53±0.35)%, and a perihelion shift of (-1.5±13.5) days.

3.
Phys Rev Lett ; 130(3): 031802, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36763398

RESUMO

We report a search for cosmic-ray boosted dark matter with protons using the 0.37 megaton×years data collected at Super-Kamiokande experiment during the 1996-2018 period (SKI-IV phase). We searched for an excess of proton recoils above the atmospheric neutrino background from the vicinity of the Galactic Center. No such excess is observed, and limits are calculated for two reference models of dark matter with either a constant interaction cross section or through a scalar mediator. This is the first experimental search for boosted dark matter with hadrons using directional information. The results present the most stringent limits on cosmic-ray boosted dark matter and exclude the dark matter-nucleon elastic scattering cross section between 10^{-33}cm^{2} and 10^{-27}cm^{2} for dark matter mass from 1 MeV/c^{2} to 300 MeV/c^{2}.

5.
Osteoarthritis Cartilage ; 30(6): 852-861, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35331859

RESUMO

OBJECTIVES: We previously reported, based on a multicenter randomized-control study, that the efficacy of intra-articular injections of hyaluronic acid (IA-HA) was not inferior to that of oral non-steroidal anti-inflammatory drugs (NSAIDs) in patients with knee osteoarthritis (OA). However, the molecular effects on the pathophysiology of knee OA remain unclear. C-terminal telopeptides of type II collagen (CTX-II) is reported to primarily originate from the interface between articular cartilage and subchondral bone, which is a site of potential remodeling in OA. We performed a predefined sub-analysis of the previous study to compare the changes of urinary CTX-II (uCTX-II) in response to IA-HA to those in response to NSAID for knee OA. DESIGN: A total of 200 knee OA patients were registered from 20 hospitals and randomized to receive IA-HA (2,700 kDa HA, 5 times at 1-week intervals) or NSAID (loxoprofen sodium, 180 mg/day) for 5 weeks. The uCTX-II levels were measured before and after treatment. RESULTS: The uCTX-II levels were significantly increased by IA-HA treatment (337.7 ± 193.8 to 370.7 ± 234.8 ng/µmol Cr) and were significantly reduced by NSAID treatment (423.2 ± 257.6 to 370.3 ± 250.9 ng/µmol Cr). The %changes of uCTX-II induced by IA-HA (11.6 ± 29.5%) and NSAID (-9.0 ± 26.7%) was significantly different (between-group difference: 20.6, 95% confidence intervals: 10.6 to 30.6). CONCLUSIONS: While both IA-HA and NSAID improved symptoms of knee OA, uCTX-II levels were increased by IA-HA and reduced by NSAIDs treatment, suggesting these treatments may improve symptoms of knee OA through different modes of action.


Assuntos
Osteoartrite do Joelho , Anti-Inflamatórios não Esteroides/uso terapêutico , Biomarcadores , Colágeno Tipo II , Humanos , Ácido Hialurônico/uso terapêutico , Injeções Intra-Articulares , Peso Molecular , Resultado do Tratamento , Viscossuplementos/uso terapêutico
6.
Cryo Letters ; 43(2): 83-90, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36626149

RESUMO

BACKGROUND: Whole-body cryotherapy (WBC) is used as a conditioning method for athletes. However, the scientific evidence for its effects is still insufficient. OBJECTIVE: To elucidate the effects of transient WBC on the expression of heat shock protein (HSP) 70 and the secretion of related hormones in humans. MATERIALS AND METHODS: The participants in this study were six healthy adult men. WBC was performed for 3 min in a booth at a temperature in the range of -150 to -120 degree C, and measurements were taken immediately before (Pre), immediately after (Post), and 60 min after WBC (Post60). For measurement of core body temperature (gastrointestinal temperature), participants ingested a capsule-type wireless temperature sensor. The body surface temperature was measured using a noncontact thermometer, and measurements were taken at four sites on the body surface (chest, abdomen, front of the thigh, and front of the lower thigh). Leukocyte count, lactate dehydrogenase, creatine kinase, hemoglobin, hematocrit, adrenaline, noradrenaline, cortisol, adrenocorticotropic hormone (ACTH), erythropoietin, and HSP70 in the collected blood were measured. RESULTS: The results showed a decrease in body surface temperature and an increase in noradrenaline and ACTH immediately after WBC. In addition, the core body temperature decreased 60 min after WBC, accompanied by an increase in HSP70 expression. CONCLUSION: WBC may increase HSP70 expression via noradrenaline and ACTH. The results of this study suggest the usefulness of WBC in triggering protein synthesis and the maintenance of immune function after training. doi.org/10.54680/fr22210110512.


Assuntos
Criopreservação , Crioterapia , Masculino , Adulto , Humanos , Crioterapia/métodos , Hormônio Adrenocorticotrópico , Norepinefrina
7.
Phys Rev Lett ; 127(26): 269902, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35029505

RESUMO

Retraction of DOI: 10.1103/PhysRevLett.102.197002.

8.
Ann Oncol ; 30(12): 1950-1958, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31566666

RESUMO

BACKGROUND: Gemcitabine plus cisplatin (GC) is the standard treatment of advanced biliary tract cancer (BTC); however, it causes nausea, vomiting, and anorexia, and requires hydration. Gemcitabine plus S-1 (GS) reportedly has equal to, or better, efficacy and an acceptable toxicity profile. We aimed to confirm the non-inferiority of GS to GC for patients with advanced/recurrent BTC in terms of overall survival (OS). PATIENTS AND METHODS: We undertook a phase III randomized trial in 33 institutions in Japan. Eligibility criteria included chemotherapy-naïve patients with recurrent or unresectable BTC, an Eastern Cooperative Oncology Group Performance Status of 0 - 1, and adequate organ function. The calculated sample size was 350 with a one-sided α of 5%, a power of 80%, and non-inferiority margin hazard ratio (HR) of 1.155. The primary end point was OS, while the secondary end points included progression-free survival (PFS), response rate (RR), adverse events (AEs), and clinically significant AEs defined as grade ≥2 fatigue, anorexia, nausea, vomiting, oral mucositis, or diarrhea. RESULTS: Between May 2013 and March 2016, 354 patients were enrolled. GS was found to be non-inferior to GC [median OS: 13.4 months with GC and 15.1 months with GS, HR, 0.945; 90% confidence interval (CI), 0.78-1.15; P = 0.046 for non-inferiority]. The median PFS was 5.8 months with GC and 6.8 months with GS (HR 0.86; 95% CI 0.70-1.07). The RR was 32.4% with GC and 29.8% with GS. Both treatments were generally well-tolerated. Clinically significant AEs were observed in 35.1% of patients in the GC arm and 29.9% in the GS arm. CONCLUSIONS: GS, which does not require hydration, should be considered a new, convenient standard of care option for patients with advanced/recurrent BTC. CLINICAL TRIAL NUMBER: This trial has been registered with the UMIN Clinical Trials Registry (http://www.umin.ac.jp/ctr/index.htm), number UMIN000010667.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias do Sistema Biliar/tratamento farmacológico , Cisplatino/administração & dosagem , Desoxicitidina/análogos & derivados , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Sistema Biliar/epidemiologia , Neoplasias do Sistema Biliar/patologia , Cisplatino/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Intervalo Livre de Doença , Combinação de Medicamentos , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Náusea/patologia , Ácido Oxônico/administração & dosagem , Ácido Oxônico/efeitos adversos , Tegafur/administração & dosagem , Tegafur/efeitos adversos , Vômito/induzido quimicamente , Vômito/patologia , Gencitabina
9.
10.
Arch Virol ; 164(1): 267-271, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30284627

RESUMO

Chronic kidney disease of unknown aetiology (CKDu) reported in Sri Lanka and other countries is a mysterious and serious disease. Recently, we reported a high seroprevalence of antibodies to a hantavirus antigen among CKDu patients in Girandurukotte, Badulla district, Sri Lanka. However, the type of hantavirus with which the residents were infected was not determined. In this study, a total of 89 seropositive sera were examined to identify their serotypes using an indirect immunofluorescent antibody assay, a truncated-N-protein-based enzyme-linked immunosorbent assay, and a cross-neutralization test. These results indicated that the residents in this area were frequently infected with Thailand orthohantavirus or an antigenically related virus.


Assuntos
Infecções por Bunyaviridae/virologia , Bunyaviridae/classificação , Bunyaviridae/isolamento & purificação , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/virologia , Infecções por Bunyaviridae/epidemiologia , Humanos , Insuficiência Renal Crônica/sangue , Sri Lanka
11.
Clin Exp Allergy ; 48(9): 1137-1146, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29781543

RESUMO

BACKGROUND: A predisposition to exacerbations is being recognized as a distinct phenotype with "previous exacerbations" representing the strongest clinical factor associated with future exacerbation. Thus, to identify additional novel biomarkers associated with asthma exacerbations, "past exacerbation status" must be included as a confounding factor. OBJECTIVE: This study aimed to characterize the clinical and biomarker features associated with asthma exacerbations in severe asthma. METHODS: We evaluated clinical parameters from 105 severe asthmatics yearly for 3 years, as well as their exacerbation status. We classified the subjects into 3 groups: (i) consistent non-exacerbators (CNE, subjects who did not experience any exacerbation over the 3-year period); (ii) consistent frequent exacerbators (CFE, subjects with frequent exacerbation, defined as those who had 2 or more exacerbations within 1 year, throughout the 3-year period); and (iii) intermittent exacerbators (IE). We conducted multivariate analysis for comparisons among the groups for multiple factors, including several Th2-related biomarkers, in addition to the "past exacerbation status." RESULTS: Thirty-nine subjects were classified as CNE, 15 as CFE, and 51 as IE. Frequent exacerbations in the previous year predicted exacerbations for the following year (P < .001). Among the several Th2-related biomarkers, only FeNO was associated with exacerbation status. When we analysed the data after the second visit, the impact of FeNO on predicting future exacerbation remained significant, even after considering the exacerbation status during the first year (P < .05). CONCLUSIONS AND CLINICAL RELEVANCE: Measurement of FeNO has a significant potential to predict future asthma exacerbation, which is independent of the "past exacerbation history."


Assuntos
Asma/epidemiologia , Adolescente , Adulto , Asma/diagnóstico , Biomarcadores , Criança , Pré-Escolar , Comorbidade , Progressão da Doença , Feminino , Seguimentos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Óxido Nítrico , Fenótipo , Prognóstico , Testes de Função Respiratória , Índice de Gravidade de Doença , Inquéritos e Questionários , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Adulto Jovem
12.
Phys Chem Chem Phys ; 20(3): 2094-2103, 2018 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-29302650

RESUMO

The therapeutic effectiveness of a drug largely depends on its bioavailability, and thus ultimately on its aqueous solubility. Hydrotropes are compounds able to enhance the solubility of hydrophobic substances in aqueous media and therefore are extensively used in the formulation of drugs and personal care products. Recently, some ionic liquids were shown to display a strong ability to enhance the solubility of biomolecules through hydrotropy. In this work, the impact of the ionic liquid chemical structures and their concentration on the solubility of ibuprofen was evaluated and compared with the performance of conventional hydrotropes. The results obtained clearly evidence the exceptional capacity of ionic liquids to enhance the solubility of ibuprofen. [C4C1im][SCN] and [C4C1im][N(CN)2] seem to be the most promising ionic liquids for ibuprofen solubilisation, where an increase in the solubility of 60- and 120-fold was observed with ionic liquid concentrations of circa 1 mol kg-1, respectively. Dynamic light scattering and molecular dynamics simulations were used to investigate the mechanism of the IL-mediated drug solubility and the results obtained indicate that the structure of aqueous solutions of ionic liquids and the role it plays in the formation of ionic liquid-drug aggregates is the mechanism driving the hydrotropic dissolution.

13.
Phys Chem Chem Phys ; 20(29): 19307-19313, 2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-29900442

RESUMO

In this work, we have found complete water miscibility for a priori, water immiscible (highly hydrophobic) ionic liquids by chemical manipulation of the quaternary ammonium cation grafted with hydroxyethyl moieties. Specifically, we were able to obtain bistriflimide-based ionic liquids completely miscible with water, even below room temperature. The underlying reason is the full integration of the OH groups of the cation in the continuous H-bonded network of water.

14.
Heredity (Edinb) ; 118(2): 193-201, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27703154

RESUMO

Numerous landscape genomic studies have identified single-nucleotide polymorphisms (SNPs) and genes potentially involved in local adaptation. Rarely, it has been explicitly evaluated whether these environmental associations also hold true beyond the populations studied. We tested whether putatively adaptive SNPs in Arabidopsis halleri (Brassicaceae), characterized in a previous study investigating local adaptation to a highly heterogeneous environment, show the same environmental associations in an independent, geographically enlarged set of 18 populations. We analysed new SNP data of 444 plants with the same methodology (partial Mantel tests, PMTs) as in the original study and additionally with a latent factor mixed model (LFMM) approach. Of the 74 candidate SNPs, 41% (PMTs) and 51% (LFMM) were associated with environmental factors in the independent data set. However, only 5% (PMTs) and 15% (LFMM) of the associations showed the same environment-allele relationships as in the original study. In total, we found 11 genes (31%) containing the same association in the original and independent data set. These can be considered prime candidate genes for environmental adaptation at a broader geographical scale. Our results suggest that selection pressures in highly heterogeneous alpine environments vary locally and signatures of selection are likely to be population-specific. Thus, genotype-by-environment interactions underlying adaptation are more heterogeneous and complex than is often assumed, which might represent a problem when testing for adaptation at specific loci.


Assuntos
Adaptação Fisiológica/genética , Arabidopsis/genética , Clima , Interação Gene-Ambiente , Polimorfismo de Nucleotídeo Único , Alelos , Genes de Plantas , Genética Populacional , Genótipo , Geografia , Modelos Lineares , Modelos Genéticos , Seleção Genética
15.
Phys Chem Chem Phys ; 19(28): 18201-18207, 2017 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-28675236

RESUMO

Fabrication of a graphene separation sheet is difficult because of the necessity for leakage-free graphene transfer onto a substrate. In this study, porous graphene sheets with thicknesses of one, two, and four layers were directly fabricated on stainless-steel mesh substrates and demonstrated to display high separation ability for H2, CO2, and CH4. The single-layer graphene sample exhibited higher permeance for these molecules than double- and four-layer graphene and displayed similar high selectivity to that of other porous materials. Permeance was proportional to molecular velocity and inversely proportional to interaction strength with graphene; molecular size-dependent permeance was not seen. Molecules that interacted strongly with graphene were attracted to the graphene surface, which hindered permeation. Such graphene surface rejection allowed graphene containing larger pores than the molecular size to provide both high molecular permeance and selectivity. The relationship between the permeance of porous graphene for H2 and H2/CO2 with selectivity suggested that its permeance was higher than that of other materials with high separation performance. Therefore, the porous graphene samples separated molecules with extremely high permeance by graphene surface rejection.

16.
Psychol Med ; 46(15): 3117-3125, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27534897

RESUMO

BACKGROUND: The Fukushima Daiichi and Daini Nuclear Power Plant workers experienced multiple stressors as both victims and onsite workers after the 2011 Great East Japan Earthquake and subsequent nuclear accidents. Previous studies found that disaster-related exposures, including discrimination/slurs, were associated with their mental health. Their long-term impact has yet to be investigated. METHOD: A total of 968 plant workers (Daiichi, n = 571; Daini, n = 397) completed self-written questionnaires 2-3 months (time 1) and 14-15 months (time 2) after the disaster (response rate 55.0%). Sociodemographics, disaster-related experiences, and peritraumatic distress were assessed at time 1. At time 1 and time 2, general psychological distress (GPD) and post-traumatic stress response (PTSR) were measured, respectively, using the K6 scale and Impact of Event Scale Revised. We examined multivariate covariates of time 2 GPD and PTSR, adjusting for autocorrelations in the hierarchical multiple regression analyses. RESULTS: Higher GPD at time 2 was predicted by higher GPD at time 1 (ß = 0.491, p < 0.001) and discrimination/slurs experiences at time 1 (ß = 0.065, p = 0.025, adjusted R 2 = 0.24). Higher PTSR at time 2 was predicted with higher PTSR at time 1 (ß = 0.548, p < 0.001), higher age (ß = 0.085, p = 0.005), and discrimination/slurs experiences at time 1 (ß = 0.079, p = 0.003, adjusted R 2 = 0.36). CONCLUSIONS: Higher GPD at time 2 was predicted by higher GPD and discrimination/slurs experience at time 1. Higher PTSR at time 2 was predicted by higher PTSR, higher age, and discrimination/slurs experience at time 1.


Assuntos
Acidente Nuclear de Fukushima , Saúde Mental , Centrais Nucleares , Preconceito/psicologia , Opinião Pública , Transtornos de Estresse Pós-Traumáticos/psicologia , Estresse Psicológico/psicologia , Adulto , Desastres , Feminino , Humanos , Japão , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Inquéritos e Questionários , Recursos Humanos
17.
J Nanobiotechnology ; 14(1): 74, 2016 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-27809857

RESUMO

BACKGROUND: The field of structural dynamics of cytoskeletons in living cells is gathering wide interest, since better understanding of cytoskeleton intracellular organization will provide us with not only insights into basic cell biology but may also enable development of new strategies in regenerative medicine and cancer therapy, fields in which cytoskeleton-dependent dynamics play a pivotal role. The nanoneedle technology is a powerful tool allowing for intracellular investigations, as it can be directly inserted into live cells by penetrating through the plasma membrane causing minimal damage to cells, under the precise manipulation using atomic force microscope. Modifications of the nanoneedles using antibodies have allowed for accurate mechanical detection of various cytoskeletal components, including actin, microtubules and intermediate filaments. However, successful penetration of the nanoneedle through the plasma membrane has been shown to vary greatly between different cell types and conditions. In an effort to overcome this problem and improve the success rate of nanoneedle insertion into the live cells, we have focused here on the fluidity of the membrane lipid bilayer, which may hinder nanoneedle penetration into the cytosolic environment. RESULTS: We aimed to reduce apparent fluidity of the membrane by either increasing the approach velocity or reducing experimental temperatures. Although changes in approach velocity did not have much effect, lowering the temperature was found to greatly improve the detection of unbinding forces, suggesting that alteration in the plasma membrane fluidity led to increase in nanoneedle penetration. CONCLUSIONS: Operation at a lower temperature of 4 °C greatly improved the success rate of nanoneedle insertion to live cells at an optimized approach velocity, while it did not affect the binding of antibodies immobilized on the nanoneedle to vimentins for mechanical detection. As these experimental parameters can be applied to various cell types, these results may improve the versatility of the nanoneedle technology to other cell lines and platforms.


Assuntos
Anticorpos Imobilizados/química , Proteínas do Citoesqueleto/análise , Nanotecnologia/instrumentação , Análise de Célula Única/instrumentação , Anticorpos Imobilizados/metabolismo , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/metabolismo , Células HeLa , Humanos , Células MCF-7 , Microscopia de Força Atômica , Microscopia de Fluorescência , Agulhas , Análise de Célula Única/métodos
19.
Phys Chem Chem Phys ; 17(17): 11560-8, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25857599

RESUMO

A model-free multivariate analysis using singular value decomposition is employed to refine an equivalent electrical circuit model in order to probe the electrochemical properties of the hematite/water interface in dilute NaCl and NH4Cl solutions using electrochemical impedance spectroscopy. The result shows that the surface protonation is directly related to the mobility and trapping of charge carriers at the mineral surface. Moreover, the point of zero charge can be found at pH where the charge transfer resistance is the highest, in addition to the minimum double layer capacitance. The inner-sphere interaction of the NH4(+) ion with the surface is indicated by an increase of capacitance for charge carrier trapping from the protonated surface as well as lower double layer capacitance and open circuit potential. It is clear that the intrinsic electrochemical activity of hematite depends on the degree of surface (de)protonation and other inner-sphere adsorption, as these processes affect the charge carrier density in the surface state. This work also highlights an important synergistic effect of the two spectral analyses that enables EIS to be utilized in an in-depth investigation of mineral/water interfaces.


Assuntos
Cloreto de Amônio/química , Espectroscopia Dielétrica , Cloreto de Sódio/química , Adsorção , Eletrólitos/química , Compostos Férricos , Íons/química , Análise Multivariada , Soluções , Propriedades de Superfície , Água/química
20.
Phys Chem Chem Phys ; 17(20): 13480-94, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25933136

RESUMO

The viscosity (η) of four binary mixtures (ionic liquids plus molecular solvents, ILs+MSs) was measured in the 283.15 < T/K < 363.15 temperature range. Different IL/MS combinations were selected in such a way that the corresponding η(T) functions exhibit crossover temperatures at which both pure components present identical viscosity values. Consequently, most of the obtained mixture isotherms, η(x), exhibit clear viscosity minima in the studied T-x range. The results are interpreted using auxiliary molecular dynamics (MD) simulation data in order to correlate the observed η(T,x) trends with the interactions in each mixture, including the balance between electrostatic forces and hydrogen bonding.

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