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1.
Phys Rev Lett ; 132(18): 186901, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38759158

RESUMEN

Electron-electron scattering on the order of a few to tens of femtoseconds plays a crucial role in the ultrafast electron dynamics of conventional metals. When mid-infrared light is used for driving and the period of light field is comparable to the scattering time in metals, unique light-driven states and nonlinear optical responses associated with the scattering process are expected to occur. Here, we use high-harmonics spectroscopy to investigate the effect of electron-electron scattering on the electron dynamics in thin film 2H-NbSe_{2} driven by a mid-infrared field. We observed odd-order high harmonics up to 9th order as well as a broadband emission from hot electrons in the energy range from 1.5 to 4.0 eV. The electron-electron scattering time in 2H-NbSe_{2} was estimated from the broadband emission to be almost the same as the period of the mid-infrared light field. A comparison between experimental results and a numerical calculation reveals that competition and cooperation between the driving and scattering enhances the nonperturbative behavior of high harmonics in metals, causing a highly nonequilibrium electronic state corresponding to several thousand Kelvin.

2.
Exp Dermatol ; 33(3): e15025, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38450766

RESUMEN

Ceramides are major constituents of stratum corneum (SC) intercellular lipids involved in skin barrier function. The ratio of molecular species of ceramides and their correlation with disease severity was examined in patients with atopic dermatitis (AD). Thirty-eight patients with AD and 32 healthy controls (HCs) were assessed for transepidermal water loss, SC collection and clinical assessment. The ceramide content of different molecular species in the samples was quantified using high-performance liquid chromatography coupled with tandem mass spectrometry. Unsaturated acyl chains of both covalently bound and free ceramides [EOS] were higher in AD lesional skin than those in AD non-lesional or normal HC skin. The proportion of unsaturated acyl chains (C30:1, C32:1 and C34:1) was higher than other ceramide molecular species among covalently bound and free ceramides [EOS] in patients with AD. The proportion of unsaturated acyl chains in covalently bound ceramides was positively correlated with transepidermal water loss (r = 0.600) when considering the total number of non-lesional and lesional skin. Additionally, thymus and activation-regulated chemokine (TARC) showed a positive correlation with unsaturated acyl chains proportion in AD non-lesional (r = 0.676) and lesional (r = 0.503) skin. Our study is the first to show the increase in unsaturated acyl chains of both covalently bound and free ceramides [EOS] in lesional and non-lesional skin in AD for each molecular species. This increase is associated with dryness and impaired barrier function, which correlates with TARC levels, a marker for the degree of type 2 inflammation. We speculate that type 2 inflammation exacerbation leads to abnormal epidermal lipid metabolism in the skin of patients with AD.


Asunto(s)
Dermatitis Atópica , Humanos , Inflamación , Gravedad del Paciente , Ceramidas , Agua
3.
Ann Oncol ; 34(3): 262-274, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36535565

RESUMEN

BACKGROUND: Patients with recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) have a poor prognosis. The phase III KESTREL study evaluated the efficacy of durvalumab [programmed death-ligand 1 (PD-L1) antibody] with or without tremelimumab [cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) antibody], versus the EXTREME regimen in patients with R/M HNSCC. PATIENTS AND METHODS: Patients with HNSCC who had not received prior systemic treatment for R/M disease were randomized (2 : 1 : 1) to receive durvalumab 1500 mg every 4 weeks (Q4W) plus tremelimumab 75 mg Q4W (up to four doses), durvalumab monotherapy 1500 mg Q4W, or the EXTREME regimen (platinum, 5-fluorouracil, and cetuximab) until disease progression. Durvalumab efficacy, with or without tremelimumab, versus the EXTREME regimen in patients with PD-L1-high tumors and in all randomized patients was assessed. Safety was also assessed. RESULTS: Durvalumab and durvalumab plus tremelimumab were not superior to EXTREME for overall survival (OS) in patients with PD-L1-high expression [median, 10.9 and 11.2 versus 10.9 months, respectively; hazard ratio (HR) = 0.96; 95% confidence interval (CI) 0.69-1.32; P = 0.787 and HR = 1.05; 95% CI 0.80-1.39, respectively]. Durvalumab and durvalumab plus tremelimumab prolonged duration of response versus EXTREME (49.3% and 48.1% versus 9.8% of patients remaining in response at 12 months), correlating with long-term OS for responding patients; however, median progression-free survival was longer with EXTREME (2.8 and 2.8 versus 5.4 months). Exploratory analyses suggested that subsequent immunotherapy use by 24.3% of patients in the EXTREME regimen arm contributed to the similar OS outcomes between arms. Grade 3/4 treatment-related adverse events (TRAEs) for durvalumab, durvalumab plus tremelimumab, and EXTREME were 8.9%, 19.1%, and 53.1%, respectively. CONCLUSIONS: In patients with PD-L1-high expression, OS was comparable between durvalumab and the EXTREME regimen. Durvalumab alone, and with tremelimumab, demonstrated durable responses and reduced TRAEs versus the EXTREME regimen in R/M HNSCC.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/etiología , Antígeno B7-H1 , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Recurrencia Local de Neoplasia , Neoplasias de Cabeza y Cuello/etiología
4.
Curr Osteoporos Rep ; 21(1): 85-94, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36477366

RESUMEN

PURPOSE OF REVIEW: Multicentric carpotarsal osteolysis (MCTO) is an ultra-rare disorder characterized by osteolysis of the carpal and tarsal bones, subtle craniofacial deformities, and nephropathy. The molecular pathways underlying the pathophysiology are not well understood. RECENT FINDINGS: MCTO is caused by heterozygous mutations in MAFB, which encodes the widely expressed transcription factor MafB. All MAFB mutations in patients with MCTO result in replacement of amino acids that cluster in a phosphorylation region of the MafB transactivation domain and account for a presumed gain-of-function for the variant protein. Since 2012, fewer than 60 patients with MCTO have been described with 20 missense mutations in MAFB. The clinical presentations are variable, and a genotype-phenotype correlation is lacking. Osteolysis, via excessive osteoclast activity, has been regarded as the primary mechanism, although anti-resorptive agents demonstrate little therapeutic benefit. This paper appraises current perspectives of MafB protein action, inflammation, and dysfunctional bone formation on the pathogenesis of the skeletal phenotype in MCTO. More research is needed to understand the pathogenesis of MCTO to develop rational therapies.


Asunto(s)
Huesos del Carpo , Osteólisis , Humanos , Osteólisis/genética , Mutación , Mutación Missense , Huesos del Carpo/patología , Fenotipo
5.
Ann Oncol ; 33(2): 216-226, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34843940

RESUMEN

BACKGROUND: Cancer of unknown primary (CUP) has a poor prognosis. Given the recent approval of immune checkpoint inhibitors for several cancer types, we carried out a multicenter phase II study to assess the efficacy of nivolumab for patients with CUP. PATIENTS AND METHODS: Patients with CUP who were previously treated with at least one line of systemic chemotherapy constituted the principal study population. Previously untreated patients with CUP were also enrolled for exploratory analysis. Nivolumab (240 mg/body) was administered every 2 weeks for up to 52 cycles. The primary endpoint was objective response rate in previously treated patients as determined by blinded independent central review according to RECIST version 1.1. RESULTS: Fifty-six patients with CUP were enrolled in the trial. For the 45 previously treated patients, objective response rate was 22.2% [95% confidence interval (CI), 11.2% to 37.1%], with a median progression-free survival and overall survival of 4.0 months (95% CI, 1.9-5.8 months) and 15.9 months (95% CI, 8.4-21.5 months), respectively. Similar clinical benefits were also observed in the 11 previously untreated patients. Better clinical efficacy of nivolumab was apparent for tumors with a higher programmed death-ligand 1 expression level, for those with a higher tumor mutation burden, and for microsatellite instability-high tumors. In contrast, no differences in efficacy were apparent between tumor subgroups based on estimated tissue of origin. Adverse events were consistent with the known safety profile of nivolumab. No treatment-related death was observed. CONCLUSIONS: Our results demonstrate a clinical benefit of nivolumab for patients with CUP, suggesting that nivolumab is a potential additional therapeutic option for CUP.


Asunto(s)
Neoplasias Primarias Desconocidas , Nivolumab , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Humanos , Inestabilidad de Microsatélites , Neoplasias Primarias Desconocidas/tratamiento farmacológico , Nivolumab/efectos adversos , Supervivencia sin Progresión , Criterios de Evaluación de Respuesta en Tumores Sólidos
6.
Osteoporos Int ; 31(6): 1089-1095, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32060561

RESUMEN

This study revealed the change in the paravertebral muscles in patients with osteoporotic vertebral fracture. Increased pain is likely to be the driver for reduced activity, reduced activities of daily living, and consequent increase in fat infiltration of the paravertebral muscles, assumed to be secondary to reduced activity level or, conversely, partial immobilization. INTRODUCTION: To reveal the time courses and impact of the paravertebral muscles (PVMs) on the healing process of osteoporotic vertebral fractures and risk factors for PVM decrease. METHODS: Consecutive patients with symptomatic osteoporotic vertebral fractures were enrolled in 11 hospitals. At enrollment and 3- and 6-month follow-up, PVMs, including the multifidus and erector spinae, were examined using magnetic resonance imaging (MRI). The PVM cross-sectional area (CSA) and fat signal fraction (FSF) were measured at L3. Low back pain (LBP), activities of daily living (ADLs), and risk factors for PVM decrease at the 6-month follow-up were investigated. PVM decrease was defined as > 1 standard deviation decrease of the CSA or > 1 standard deviation increase of the FSF. RESULTS: Among 153 patients who completed the 6-month follow-up, 117 (92 women, 79%) had MRI of L3 at enrollment and 3- and 6-month follow-up (mean age at enrollment, 78.5 years). The CSA did not change 6 months from onset (p for trend = 0.634), whereas the FSF significantly increased (p for trend = 0.033). PVM decrease was observed in 30 patients (26%). LBP was more severe, and delayed union was more frequent in patients with PVM decrease (p = 0.021 mixed-effect model and p = 0.029 chi-square test, respectively). The risk factors for PVM decrease were ADL decline at the 3-month follow-up (adjusted odds ratio = 5.35, p = 0.026). CONCLUSION: PVM decrease was significantly related to LBP and delayed union after osteoporotic vertebral fracture onset. ADL decline at the 3-month follow-up was a risk factor for PVM decrease. Therefore, restoring ADLs within 3 months after onset is important.


Asunto(s)
Actividades Cotidianas , Músculos de la Espalda/fisiopatología , Dolor de la Región Lumbar , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Anciano , Femenino , Humanos , Dolor de la Región Lumbar/etiología , Imagen por Resonancia Magnética , Masculino , Fracturas Osteoporóticas/complicaciones , Fracturas Osteoporóticas/fisiopatología , Fracturas de la Columna Vertebral/complicaciones , Fracturas de la Columna Vertebral/fisiopatología
7.
Reprod Biol Endocrinol ; 18(1): 57, 2020 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-32471441

RESUMEN

BACKGROUND: A recently published Position Statement (PS) by the Preimplantation Genetics Diagnosis International Society (PGDIS) regarding utilization of preimplantation genetic testing for aneuploidy (PGT-A) in association with in vitro fertilization (IVF) contained inaccuracies and misrepresentations. Because opinions issued by the PGDIS have since 2016 determined worldwide IVF practice, corrections appear of importance. METHODS: The International Do No Harm Group in IVF (IDNHG-IVF) is a spontaneously coalesced body of international investigators, concerned with increasing utilization of add-ons to IVF. It is responsible for the presented consensus statement, which as a final document was reached after review of the pertinent literature and again revised after the recent publication of the STAR trial and related commentaries. RESULTS: In contrast to the PGDIA-PS, we recommend restrictions to the increasing, and by IVF centers now often even mandated, utilization of PGT-A in IVF cycles. While PGT-A has been proposed as a tool for achieving enhanced singleton livebirth outcomes through embryo selection, continued false-positive rates and increasing evidence for embryonic self-correction downstream from the testing stage, has led IDNHG-IVF to conclude that currently available data are insufficient to impose overreaching recommendations for PGT-A utilization. DISCUSSION: Here presented consensus offers an alternative to the 2019 PGDIS position statement regarding utilization of preimplantation genetic testing for aneuploidy (PGT-A) in association with in vitro fertilization (IVF). Mindful of what appears to offer best outcomes for patients, and in full consideration of patient autonomy, here presented opinion is based on best available evidence, with the goal of improving safety and efficacy of IVF and minimizing wastage of embryos with potential for healthy births. CONCLUSIONS: As the PGDIS never suggested restrictions on clinical utilization of PGT-A in IVF, here presented rebuttal represents an act of self-regulation by parts of the IVF community in attempts to control increasing utilization of different unproven recent add-ons to IVF.


Asunto(s)
Aneuploidia , Transferencia de Embrión/normas , Fertilización In Vitro , Mosaicismo , Diagnóstico Preimplantación/normas , Blastocisto , Reacciones Falso Positivas , Femenino , Humanos , Embarazo
8.
J Chem Phys ; 150(13): 134702, 2019 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-30954059

RESUMEN

Nanodiamonds (NDs) hosting nitrogen-vacancy (NV) centers are a promising platform for quantum sensing applications. Sensitivity of the applications using NV centers in NDs is often limited due to the presence of paramagnetic impurity contents near the ND surface. Here, we investigate near-surface paramagnetic impurities in NDs. Using high-frequency (HF) electron paramagnetic resonance spectroscopy, the near-surface paramagnetic impurity within the shell of NDs is probed and its g-value is determined to be 2.0028(3). Furthermore, HF electron-electron double resonance-detected nuclear magnetic resonance spectroscopy and a first principles calculation show that a possible structure of the near-surface impurity is the negatively charged vacancy V-. The identification of the near-surface impurity by the present investigation provides a promising pathway to improve the NV properties in NDs and the NV-based sensing techniques.

9.
Ann Oncol ; 29(3): 624-631, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29293874

RESUMEN

Background: Combination therapy with oral fluoropyrimidine and irinotecan has not yet been established as first-line treatment of metastatic colorectal cancer (mCRC). We carried out a randomized, open-label, phase III trial to determine whether S-1 and irinotecan plus bevacizumab is noninferior to mFOLFOX6 or CapeOX plus bevacizumab in terms of progression-free survival (PFS). Patients and methods: Patients from 53 institutions who had previously untreated mCRC were randomly assigned (1 : 1) to receive either mFOLFOX6 or CapeOX plus bevacizumab (control group) or S-1 and irinotecan plus bevacizumab (experimental group; a 3-week regimen: intravenous infusions of irinotecan 150 mg/m2 and bevacizumab 7.5 mg/kg on day 1, oral S-1 80 mg/m2 twice daily for 2 weeks, followed by a 1-week rest; or a 4-week regimen: irinotecan 100 mg/m2 and bevacizumab 5 mg/kg on days 1 and 15, S-1 80 mg/m2 twice daily for 2 weeks, followed by a 2-week rest). The primary end point was PFS. The noninferiority margin was 1.25; noninferiority would be established if the upper limit of the 95% confidence interval (CI) for the hazard ratio (HR) of the control group versus the experimental group was less than this margin. Result: Between June 2012 and September 2014, 487 patients underwent randomization. Two hundred and forty-three patients assigned to the control group and 241 assigned to the experimental group were included in the primary analysis. Median PFS was 10.8 months (95% CI 9.6-11.6) in the control group and 14.0 months (95% CI 12.4-15.5) in the experimental group (HR 0.84, 95% CI 0.70-1.02; P < 0.0001 for noninferiority, P = 0.0815 for superiority). One hundred and fifty-seven patients (64.9%) in the control group and 140 (58.6%) in the experimental group had adverse events of grade 3 or higher. Conclusion: S-1 and irinotecan plus bevacizumab is noninferior to mFOLFOX6 or CapeOX plus bevacizumab with respect to PFS as first-line treatment of mCRC and could be a new standard treatment. Clinical trials number: UMIN000007834.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Adenocarcinoma/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Bevacizumab/administración & dosificación , Capecitabina/administración & dosificación , Neoplasias Colorrectales/mortalidad , Supervivencia sin Enfermedad , Combinación de Medicamentos , Femenino , Fluorouracilo/administración & dosificación , Humanos , Irinotecán/administración & dosificación , Estimación de Kaplan-Meier , Leucovorina/administración & dosificación , Masculino , Persona de Mediana Edad , Compuestos Organoplatinos/administración & dosificación , Oxaliplatino/administración & dosificación , Ácido Oxónico/administración & dosificación , Supervivencia sin Progresión , Tegafur/administración & dosificación , Adulto Joven
10.
Ann Oncol ; 29(4): 1004-1009, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29408977

RESUMEN

Background: The standard of care for first-line treatment of recurrent and/or metastatic squamous cell carcinoma of the head and neck (R/M SCCHN) is combination treatment with platinum, 5-FU and cetuximab (PFE). However, this regimen requires hospitalization to ensure proper hydration and continuous infusion of 5-FU, and causes severe nausea and anorexia. We evaluated the efficacy and safety of paclitaxel, carboplatin and cetuximab (PCE) as first-line treatment in patients with R/M SCCHN. Patients and methods: Eligibility criteria included recurrent and/or metastatic, histologically proven SCC of the oropharynx, oral cavity, hypopharynx or larynx; PS 0-1; adequate organ function; no suitable local therapy for R/M SCCHN; and no prior systemic chemotherapy for R/M SCCHN. Chemotherapy consisted of paclitaxel 100 mg/m2 on days 1, 8; carboplatin area under the blood concentration-time curve 2.5 on days 1, 8, repeated every 3 weeks for up to 6 cycles; and cetuximab at an initial dose of 400 mg/m2, followed by 250 mg/m2 weekly until disease progression or unacceptable toxicities. Primary end point was overall response rate. Secondary end points were safety, treatment completion rate, progression-free survival, overall survival, and clinical benefit rate. Planned sample size was 45 patients. Results: Forty-seven subjects were accrued from July 2013 to October 2014. Of 45 evaluable, 40 were male; median age was 63 years; Eastern Cooperative Oncology Group Performance Status was 0/1 in 23/22 cases; site was the hypopharynx/oropharynx/oral cavity/larynx in 17/11/10/7 cases; and 36/9 cases were smokers/nonsmokers, respectively. Overall response rate, the primary end point, was 40%. Median overall survival was 14.7 months and progression-free survival was 5.2 months. Grade 3/4 adverse events included neutropenia (68%), skin reaction (15%), fatigue (9%) and febrile neutropenia (9%). A potentially treatment-related death occurred in one patient with intestinal pneumonia. Conclusions: The PCE regimen shows promising activity with acceptable toxicity in the outpatient clinic. Further studies are needed to compare PCE with PFE in this population. Registered clinical trial number: UMIN000010507.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carboplatino/administración & dosificación , Cetuximab/administración & dosificación , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Metástasis de la Neoplasia , Paclitaxel/administración & dosificación , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Persona de Mediana Edad , Recurrencia , Carcinoma de Células Escamosas de Cabeza y Cuello/patología
11.
J Viral Hepat ; 25(11): 1312-1320, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29770539

RESUMEN

This study aimed to determine the incidence and risk factors for hepatitis B virus (HBV) reactivation in patients with rheumatoid arthritis (RA) undergoing immunosuppressive therapy. The National Database of Japan, in which insurance claim data have been comprehensively accumulated, was utilized. The subjects were 76 641 RA patients who were plausibly initiated on immunosuppressive therapy from April 2013 to March 2014. Laboratory tests of the hepatitis B surface antigen, anti-hepatitis B virus surface antibody, and anti-hepatitis B virus core antibody were performed in 28.23%, 12.52% and 14.63% of patients, respectively, when the therapy was initiated. We found that HBV reactivation and fulminant hepatitis occurred in both the patients with and without HBV DNA monitoring, indicating insufficient monitoring in Japan during the study. The cumulative incidence of HBV reactivation over 24 months was 1.57% (95% confidence interval [CI] = 1.28%-1.92%) in the monitoring group, which consisted of those with resolved HBV infection. Glucocorticoid administration was a potent risk factor for HBV reactivation (hazard ratio [HR]  = 1.70, 95% CI = 1.26-2.29, P = .001 in all subjects, and HR = 1.82, 95% CI = 1.18-2.81, P = .007 in the nonmonitoring group), although it was not statistically significant in the monitoring group (HR = 1.49, 95% CI = 0.99-2.26 and P = .057). No significant risk difference was observed between single administration of methotrexate and biological drugs.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/inmunología , Virus de la Hepatitis B/fisiología , Hepatitis B Crónica/virología , Inmunosupresores/uso terapéutico , Activación Viral , Adulto , Anciano , Artritis Reumatoide/epidemiología , Artritis Reumatoide/virología , ADN Viral/sangre , Femenino , Anticuerpos contra la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/epidemiología , Hepatitis B Crónica/inmunología , Humanos , Inmunosupresores/efectos adversos , Incidencia , Reembolso de Seguro de Salud/estadística & datos numéricos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Factores de Riesgo
12.
Nature ; 489(7416): 409-13, 2012 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-22996555

RESUMEN

Electron paramagnetic resonance (EPR) spectroscopy interrogates unpaired electron spins in solids and liquids to reveal local structure and dynamics; for example, EPR has elucidated parts of the structure of protein complexes that other techniques in structural biology have not been able to reveal. EPR can also probe the interplay of light and electricity in organic solar cells and light-emitting diodes, and the origin of decoherence in condensed matter, which is of fundamental importance to the development of quantum information processors. Like nuclear magnetic resonance, EPR spectroscopy becomes more powerful at high magnetic fields and frequencies, and with excitation by coherent pulses rather than continuous waves. However, the difficulty of generating sequences of powerful pulses at frequencies above 100 gigahertz has, until now, confined high-power pulsed EPR to magnetic fields of 3.5 teslas and below. Here we demonstrate that one-kilowatt pulses from a free-electron laser can power a pulsed EPR spectrometer at 240 gigahertz (8.5 teslas), providing transformative enhancements over the alternative, a state-of-the-art ∼30-milliwatt solid-state source. Our spectrometer can rotate spin-1/2 electrons through π/2 in only 6 nanoseconds (compared to 300 nanoseconds with the solid-state source). Fourier-transform EPR on nitrogen impurities in diamond demonstrates excitation and detection of EPR lines separated by about 200 megahertz. We measured decoherence times as short as 63 nanoseconds, in a frozen solution of nitroxide free-radicals at temperatures as high as 190 kelvin. Both free-electron lasers and the quasi-optical technology developed for the spectrometer are scalable to frequencies well in excess of one terahertz, opening the way to high-power pulsed EPR spectroscopy up to the highest static magnetic fields currently available.


Asunto(s)
Espectroscopía de Resonancia por Spin del Electrón/instrumentación , Espectroscopía de Resonancia por Spin del Electrón/métodos , Electrones , Rayos Láser , Compuestos Alílicos/química , Benceno/química , Óxidos N-Cíclicos/química , Diamante/química , Análisis de Fourier , Radicales Libres/química , Óxidos de Nitrógeno/química , Temperatura , Factores de Tiempo
13.
J Clin Pharm Ther ; 43(1): 36-44, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28749016

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Study design and statistical methods have become core components of medical research, and the methodology has become more multifaceted and complicated over time. The study of the comprehensive details and current trends of study design and statistical methods is required to support the future implementation of well-planned clinical studies providing information about evidence-based medicine. Our purpose was to illustrate study design and statistical methods employed in recent medical literature. METHODS: This was an extension study of Sato et al. (N Engl J Med 2017; 376: 1086-1087), which reviewed 238 articles published in 2015 in the New England Journal of Medicine (NEJM) and briefly summarized the statistical methods employed in NEJM. Using the same database, we performed a new investigation of the detailed trends in study design and individual statistical methods that were not reported in the Sato study. RESULTS AND DISCUSSION: Due to the CONSORT statement, prespecification and justification of sample size are obligatory in planning intervention studies. Although standard survival methods (eg Kaplan-Meier estimator and Cox regression model) were most frequently applied, the Gray test and Fine-Gray proportional hazard model for considering competing risks were sometimes used for a more valid statistical inference. With respect to handling missing data, model-based methods, which are valid for missing-at-random data, were more frequently used than single imputation methods. These methods are not recommended as a primary analysis, but they have been applied in many clinical trials. Group sequential design with interim analyses was one of the standard designs, and novel design, such as adaptive dose selection and sample size re-estimation, was sometimes employed in NEJM. WHAT IS NEW AND CONCLUSION: Model-based approaches for handling missing data should replace single imputation methods for primary analysis in the light of the information found in some publications. Use of adaptive design with interim analyses is increasing after the presentation of the FDA guidance for adaptive design.


Asunto(s)
Investigación Biomédica/tendencias , Proyectos de Investigación/tendencias , Interpretación Estadística de Datos , Medicina Basada en la Evidencia/tendencias , Humanos , Modelos Estadísticos , Publicaciones/tendencias
14.
Clin Exp Immunol ; 188(1): 22-35, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27936495

RESUMEN

Various transcription factors are also known to enhance or suppress T helper type 17 (Th17) differentiation. We have shown previously that the development of collagen-induced arthritis was suppressed in T-bet transgenic (T-bet Tg) mice, and T-bet seemed to suppress Th17 differentiation through an interferon (IFN)-γ-independent pathway, although the precise mechanism remains to be clarified. The present study was designed to investigate further the mechanisms involved in the regulation of Th17 differentiation by T-bet over-expression, and we found the new relationship between T-bet and aryl hydrocarbon receptor (AHR). Both T-bet Tg mice and IFN-γ-/- -over-expressing T-bet (T-bet Tg/IFN-γ-/- ) mice showed inhibition of retinoic acid-related orphan receptor (ROR)γt expression and IL-17 production by CD4+ T cells cultured under conditions that promote Th-17 differentiation, and decreased IL-6 receptor (IL-6R) expression and signal transducer and activator of transcription-3 (STAT-3) phosphorylation in CD4+ T cells. The mRNA expression of ahr and rorc were suppressed in CD4+ T cells cultured under Th-17 conditions from T-bet Tg mice and T-bet Tg/IFN-γ-/- mice. CD4+ T cells of wild-type (WT) and IFN-γ-/- mice transduced with T-bet-expressing retrovirus also showed inhibition of IL-17 production, whereas T-bet transduction had no effect on IL-6R expression and STAT-3 phosphorylation. Interestingly, the mRNA expression of ahr and rorc were suppressed in CD4+ T cells with T-bet transduction cultured under Th17 conditions. The enhancement of interleukin (IL)-17 production from CD4+ T cells by the addition of AHR ligand with Th17 conditions was cancelled by T-bet over-expression. Our findings suggest that T-bet over-expression-induced suppression of Th17 differentiation is mediated through IFN-γ-independent AHR suppression.


Asunto(s)
Diferenciación Celular , Expresión Génica , Interferón gamma/metabolismo , Receptores de Hidrocarburo de Aril/metabolismo , Transducción de Señal , Proteínas de Dominio T Box/genética , Células Th17/citología , Células Th17/metabolismo , Animales , Artritis Experimental/genética , Artritis Experimental/inmunología , Artritis Experimental/metabolismo , Artritis Experimental/patología , Diferenciación Celular/genética , Células Cultivadas , Modelos Animales de Enfermedad , Inmunomodulación , Inmunofenotipificación , Interferón gamma/genética , Interleucina-6/metabolismo , Ratones , Ratones Noqueados , Ratones Transgénicos , Modelos Biológicos , Factor de Transcripción STAT3/metabolismo , Subgrupos de Linfocitos T/citología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Células Th17/inmunología , Transducción Genética
16.
Osteoporos Int ; 28(2): 473-482, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27577726

RESUMEN

This study revealed the time course of osteoporotic vertebral fracture by magnetic resonance imaging using a simple classification. Signal changes were associated with the compression degree and mobility of the fractured vertebral body. This classification showed sufficient reliability in categorizing magnetic resonance imaging findings of osteoporotic vertebral fractures. INTRODUCTION: Magnetic resonance imaging (MRI) is useful in diagnosing osteoporotic vertebral fractures (OVFs). This study investigated the time course of OVFs by MRI using a simple classification. METHODS: This multicenter cohort study was performed from 2012 to 2015. Consecutive patients with ≤2-week-old OVFs were enrolled in 11 institutions. MRI was performed at enrollment and at 1-, 3-, 6-, and 12-month follow-up. Signal changes on T1-weighted imaging (T1WI), T2WI, and short τ inversion recovery (STIR) were classified according to signal intensity. Height and angular motion of vertebral bodies were also measured. RESULTS: The 6-month follow-up was completed by 153 patients. At enrollment, fractured vertebrae signal changes were 43 % diffuse and 57 % confined low on T1WI; on T2WI, 56, 24, and 5 % were confined low, high, and diffuse low, respectively; on STIR, 100 % were high. On T1WI, diffuse low remained most common (90 % at 1 month and 60 % at 3 months) until 6 and 12 months, when most were confined low (54 and 52 %, respectively). On T2WI, confined low remained most common (decreasing to 41 % at 12 months). On STIR, high signal change was shown in 98, 87, and 64 % at 3, 6, and 12 months, respectively. At 3, 6, and 12 months, diffuse low signal change was associated with significantly lower vertebral height, and high signal change was associated with significantly greater angular motion. CONCLUSIONS: MRI signal changes were associated with the compression degree and angular motion of fractured vertebrae. This classification showed sufficient reliability in categorizing MRI findings of OVFs.


Asunto(s)
Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas de la Columna Vertebral/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Curación de Fractura , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Variaciones Dependientes del Observador , Fracturas Osteoporóticas/patología , Pronóstico , Estudios Prospectivos , Reproducibilidad de los Resultados , Fracturas de la Columna Vertebral/patología
17.
BMC Cancer ; 17(1): 314, 2017 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-28476132

RESUMEN

BACKGROUND: Recent preclinical and phase I studies have reported that rebamipide decreased the severity of chemoradiotherapy-induced oral mucositis in patients with oral cancer. This placebo-controlled randomized phase II study assessed the clinical benefit of rebamipide in reducing the incidence of severe chemoradiotherapy-induced oral mucositis in patients with head and neck cancer (HNC). METHODS: Patients aged 20-75 years with HNC who were scheduled to receive chemoradiotherapy were enrolled. Patients were randomized to receive rebamipide 2% liquid, rebamipide 4% liquid, or placebo. The primary endpoint was the incidence of grade ≥ 3 oral mucositis determined by clinical examination and assessed by central review according to the Common Terminology Criteria of Adverse Events version 3.0. Secondary endpoints were the time to onset of grade ≥ 3 oral mucositis and the incidence of functional impairment (grade ≥ 3) based on the evaluation by the Oral Mucositis Evaluation Committee. RESULTS: From April 2014 to August 2015, 97 patients with HNC were enrolled, of whom 94 received treatment. The incidence of grade ≥ 3 oral mucositis was 29% and 25% in the rebamipide 2% and 4% groups, respectively, compared with 39% in the placebo group. The proportion of patients who did not develop grade ≥ 3 oral mucositis by day 50 of treatment was 57.9% in the placebo group, whereas the proportion was 68.0% in the rebamipide 2% group and 71.3% in the rebamipide 4% group. The incidences of adverse events potentially related to the study drug were 16%, 26%, and 13% in the placebo, rebamipide 2%, and rebamipide 4% groups, respectively. There was no significant difference in treatment compliance among the groups. CONCLUSIONS: The present phase II study suggests that mouth washing with rebamipide may be effective and safe for patients with HNC receiving chemoradiotherapy, and 4% liquid is the optimal dose of rebamipide. TRIAL REGISTRATION: ClinicalTrials.gov under the identifier NCT02085460 (the date of trial registration: March 11, 2014).


Asunto(s)
Alanina/análogos & derivados , Quimioradioterapia/efectos adversos , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Quinolonas/administración & dosificación , Estomatitis/tratamiento farmacológico , Adulto , Anciano , Alanina/administración & dosificación , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Neoplasias de Cabeza y Cuello/complicaciones , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Persona de Mediana Edad , Estomatitis/inducido químicamente , Estomatitis/patología
18.
Nature ; 476(7358): 76-9, 2011 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-21775988

RESUMEN

Quantum decoherence is a central concept in physics. Applications such as quantum information processing depend on understanding it; there are even fundamental theories proposed that go beyond quantum mechanics, in which the breakdown of quantum theory would appear as an 'intrinsic' decoherence, mimicking the more familiar environmental decoherence processes. Such applications cannot be optimized, and such theories cannot be tested, until we have a firm handle on ordinary environmental decoherence processes. Here we show that the theory for insulating electronic spin systems can make accurate and testable predictions for environmental decoherence in molecular-based quantum magnets. Experiments on molecular magnets have successfully demonstrated quantum-coherent phenomena but the decoherence processes that ultimately limit such behaviour were not well constrained. For molecular magnets, theory predicts three principal contributions to environmental decoherence: from phonons, from nuclear spins and from intermolecular dipolar interactions. We use high magnetic fields on single crystals of Fe(8) molecular magnets (in which the Fe ions are surrounded by organic ligands) to suppress dipolar and nuclear-spin decoherence. In these high-field experiments, we find that the decoherence time varies strongly as a function of temperature and magnetic field. The theoretical predictions are fully verified experimentally, and there are no other visible decoherence sources. In these high fields, we obtain a maximum decoherence quality-factor of 1.49 × 10(6); our investigation suggests that the environmental decoherence time can be extended up to about 500 microseconds, with a decoherence quality factor of ∼6 × 10(7), by optimizing the temperature, magnetic field and nuclear isotopic concentrations.

19.
Nat Mater ; 14(7): 675-8, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25985459

RESUMEN

In some materials the competition between superconductivity and magnetism brings about a variety of unique phenomena such as the coexistence of superconductivity and magnetism in heavy-fermion superconductors or spin-triplet supercurrent in ferromagnetic Josephson junctions. Recent observations of spin-charge separation in a lateral spin valve with a superconductor evidence that these remarkable properties are applicable to spintronics, although there are still few works exploring this possibility. Here, we report the experimental observation of the quasiparticle-mediated spin Hall effect in a superconductor, NbN. This compound exhibits the inverse spin Hall (ISH) effect even below the superconducting transition temperature. Surprisingly, the ISH signal increases by more than 2,000 times compared with that in the normal state with a decrease of the injected spin current. The effect disappears when the distance between the voltage probes becomes larger than the charge imbalance length, corroborating that the huge ISH signals measured are mediated by quasiparticles.

20.
Osteoporos Int ; 27(12): 3567-3575, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27344644

RESUMEN

This study demonstrated the predictive values of radiological findings for delayed union after osteoporotic vertebral fractures (OVFs). High-signal changes on T2WI were useful findings. INTRODUCTION: The purpose of the present study is to determine predictive radiological findings for delayed union by magnetic resonance imaging (MRI) and plain X-rays at two time points in the acute phase of OVFs. METHODS: This multicenter cohort study was performed from 2012 to 2015. A total of 218 consecutive patients with OVFs ≤2 weeks old were enrolled. MRIs and plain X-rays were performed at the time of enrollment and at 1- and 6-month follow-ups. Signal changes on T1-weighted imaging (T1WI) were classified as diffuse low-, confined low-, or no-signal change; those on T2WI were classified as high (similar to the intensity of cerebrospinal fluid), confined low-, diffuse low-, or no-signal change. The angular motion of the fractured vertebral body was measured with X-rays. RESULTS: A total of 153 patients completed the 6-month follow-up. A high-signal change on T2WI was most useful in predicting delayed union. Sensitivity, specificity, and positive predictive values were 53.3, 87.8, and 51.6 % at enrollment and 65.5, 84.8, and 51.4 % at the 1-month follow-up, respectively. The positive predictive value increased to 62.5 % with observation of high- or diffuse low-signal changes at both enrollment and the 1-month follow-up. The cutoff value of vertebral motion was 5 degrees. Sensitivity and specificity at enrollment were 52.4 and 74.1 %, respectively. CONCLUSIONS: This study demonstrated the radiological factors predicting delayed union after an OVF. T2 high-signal changes showed the strongest association with delayed union. Consecutive MRIs were particularly useful as a differential tool to predict delayed union following OVFs.


Asunto(s)
Fracturas no Consolidadas/diagnóstico por imagen , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas de la Columna Vertebral/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Fracturas no Consolidadas/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Valor Predictivo de las Pruebas , Radiografía , Sensibilidad y Especificidad , Fracturas de la Columna Vertebral/patología , Columna Vertebral
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