39 research outputs found

    Quantum-well states in ultrathin Ag(111) films deposited onto H-passivated Si(111)-(1x1) surfaces

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    Ag(111) films were deposited at room temperature onto H-passivated Si(111)-(1x1) substrates, and subsequently annealed at 300 C. An abrupt non-reactive Ag/Si interface is formed, and very uniform non-strained Ag(111) films of 6-12 monolayers have been grown. Angle resolved photoemission spectroscopy has been used to study the valence band electronic properties of these films. Well-defined Ag sp quantum-well states (QWS) have been observed at discrete energies between 0.5-2eV below the Fermi level, and their dispersions have been measured along the GammaK, GammaMM'and GammaL symmetry directions. QWS show a parabolic bidimensional dispersion, with in-plane effective mass of 0.38-0.50mo, along the GammaK and GammaMM' directions, whereas no dispersion has been found along the GammaL direction, indicating the low-dimensional electronic character of these states. The binding energy dependence of the QWS as a function of Ag film thickness has been analyzed in the framework of the phase accumulation model. According to this model, a reflectivity of 70% has been estimated for the Ag-sp states at the Ag/H/Si(111)-(1x1) interface.Comment: 6 pages, 6 figures, submitted to Phys. Rev.

    PARL deficiency in mouse causes Complex III defects, coenzyme Q depletion, and Leigh-like syndrome

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    The mitochondrial intramembrane rhomboid protease PARL has been implicated in diverse functions in vitro, but its physiological role in vivo remains unclear. Here we show that ablation in mouse causes a necrotizing encephalomyelopathy similar to Leigh syndrome, a mitochondrial disease characterized by disrupted energy production. Mice with conditional PARL deficiency in the nervous system, but not in muscle, develop a similar phenotype as germline KOs, demonstrating the vital role of PARL in neurological homeostasis. Genetic modification of two major PARL substrates, PINK1 and PGAM5, do not modify this severe neurological phenotype. brain mitochondria are affected by progressive ultrastructural changes and by defects in Complex III (CIII) activity, coenzyme Q (CoQ) biosynthesis, and mitochondrial calcium metabolism. PARL is necessary for the stable expression of TTC19, which is required for CIII activity, and of COQ4, which is essential in CoQ biosynthesis. Thus, PARL plays a previously overlooked constitutive role in the maintenance of the respiratory chain in the nervous system, and its deficiency causes progressive mitochondrial dysfunction and structural abnormalities leading to neuronal necrosis and Leigh-like syndrome

    Multicenter phase II study of plitidepsin in patients with relapsed/refractory non-Hodgkin's lymphoma

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    This phase II clinical trial evaluated the efficacy, safety and pharmacokinetics of plitidepsin 3.2 mg/m2 administered as a 1-hour intravenous infusion weekly on days 1, 8 and 15 every 4 weeks in 67 adult patients with relapsed/refractory aggressive non-Hodgkin's lymphoma. Patients were divided into two cohorts: those with non-cutaneous peripheral T-cell lymphoma (n=34) and those with other lymphomas (n=33). Efficacy was evaluated using the International Working Group criteria (1999). Of the 29 evaluable patients with non-cutaneous peripheral T-cell lymphoma, six had a response (overall response rate 20.7%; 95% confidence interval, 8.0%-39.7%), including two complete responses and four partial responses. No responses occurred in the 30 evaluable patients with other lymphomas (including 27 B-cell lymphomas). The most common plitidepsin-related adverse events were nausea, fatigue and myalgia (grade 3 in <10% of cases). Severe laboratory abnormalities (lymphopenia, anemia, thrombo- cytopenia, and increased levels of transaminase and creatine phosphokinase) were transient and easily managed by plitidepsin dose adjustments. The pharmacokinetic profile did not differ from that previously reported in patients with solid tumors. In conclusion, plitidepsin monotherapy has clinical activity in relapsed/refractory T-cell lymphomas. Combinations of plitidepsin with other chemotherapeutic drugs deserve further evaluation in patients with non-cutaneous peripheral T-cell lymphoma. (clinicaltrials.gov identifier: NCT00884286)

    As múltiplas funções da agricultura familiar: um estudo no assentamento Monte Alegre, região de Araraquara (SP).

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    A partir da emergência da ideia de sustentabilidade, a agricultura adquiriu novas conotações, associadas não apenas ao aspecto produtivo, mas também à conservação dos recursos naturais e dos territórios rurais, em um reconhecimento de sua multifuncionalidade. Com base nesta noção, que valoriza as funções socioambientais desempenhadas pelas famílias rurais e pelas agriculturas praticadas, o presente artigo analisa um assentamento rural no estado de São Paulo, buscando identificar quais são e de que forma se expressam as funções para além da produção neste território particular. Por meio de uma metodologia de cunho quali-quantitativo, observou-se que, no assentamento em foco, a agricultura encerra em si questões de coesão territorial, manutenção da segurança alimentar, conservação da agrobiodiversidade e de fomento a outras atividades produtivas, sendo o elemento central da reconstrução de um modo de vida rural neste ambiente

    Relación entre la grasa corporal y la expresión de ira en personas que realizan ejercicio regularmente

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    La actividad física proporciona benecios, tanto a la población sana como enferma, pero también puede derivar en problemas psicológicos y emocionales como respuesta al estrés. Además, aquellos atletas con menor peso corporal presentan indicadores más elevados de depresión e ira. Se plantea determinar la relación de la grasa corporal sobre la expresión de ira y entender la relación entre distintos comportamientos psicológicos, en personas físicamente activas. 264 sujetos cumplimentaron el Inventario de Expresión de Ira Estado-Rasgo, versión 2, para el estudio sobre las características de la ira y sus efectos en la salud mental y física. Se tomaron medidas antropométricas (peso, talla, IMC, porcentaje de grasa corporal, masa libre de grasa). Se calcularon distintos percentiles en función del género y edad, clasicando a los participantes en tres grupos: percentil &lt;45, entre 45 y 55 y &gt;55 de grasa corporal. Se analizaron distintos comportamientos en relación al STAXI-2 y a los distintos percentiles, pero sin encontrar diferencias significativas entre la ira y los tres grupos.

    Effectiveness of an mHealth intervention combining a smartphone app and smart band on body composition in an overweight and obese population: Randomized controlled trial (EVIDENT 3 study)

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    Background: Mobile health (mHealth) is currently among the supporting elements that may contribute to an improvement in health markers by helping people adopt healthier lifestyles. mHealth interventions have been widely reported to achieve greater weight loss than other approaches, but their effect on body composition remains unclear. Objective: This study aimed to assess the short-term (3 months) effectiveness of a mobile app and a smart band for losing weight and changing body composition in sedentary Spanish adults who are overweight or obese. Methods: A randomized controlled, multicenter clinical trial was conducted involving the participation of 440 subjects from primary care centers, with 231 subjects in the intervention group (IG; counselling with smartphone app and smart band) and 209 in the control group (CG; counselling only). Both groups were counselled about healthy diet and physical activity. For the 3-month intervention period, the IG was trained to use a smartphone app that involved self-monitoring and tailored feedback, as well as a smart band that recorded daily physical activity (Mi Band 2, Xiaomi). Body composition was measured using the InBody 230 bioimpedance device (InBody Co., Ltd), and physical activity was measured using the International Physical Activity Questionnaire. Results: The mHealth intervention produced a greater loss of body weight (–1.97 kg, 95% CI –2.39 to –1.54) relative to standard counselling at 3 months (–1.13 kg, 95% CI –1.56 to –0.69). Comparing groups, the IG achieved a weight loss of 0.84 kg more than the CG at 3 months. The IG showed a decrease in body fat mass (BFM; –1.84 kg, 95% CI –2.48 to –1.20), percentage of body fat (PBF; –1.22%, 95% CI –1.82% to 0.62%), and BMI (–0.77 kg/m2, 95% CI –0.96 to 0.57). No significant changes were observed in any of these parameters in men; among women, there was a significant decrease in BMI in the IG compared with the CG. When subjects were grouped according to baseline BMI, the overweight group experienced a change in BFM of –1.18 kg (95% CI –2.30 to –0.06) and BMI of –0.47 kg/m2 (95% CI –0.80 to –0.13), whereas the obese group only experienced a change in BMI of –0.53 kg/m2 (95% CI –0.86 to –0.19). When the data were analyzed according to physical activity, the moderate-vigorous physical activity group showed significant changes in BFM of –1.03 kg (95% CI –1.74 to –0.33), PBF of –0.76% (95% CI –1.32% to –0.20%), and BMI of –0.5 kg/m2 (95% CI –0.83 to –0.19). Conclusions: The results from this multicenter, randomized controlled clinical trial study show that compared with standard counselling alone, adding a self-reported app and a smart band obtained beneficial results in terms of weight loss and a reduction in BFM and PBF in female subjects with a BMI less than 30 kg/m2 and a moderate-vigorous physical activity level. Nevertheless, further studies are needed to ensure that this profile benefits more than others from this intervention and to investigate modifications of this intervention to achieve a global effect

    Autoantibodies against type I IFNs in patients with life-threatening COVID-19

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    Interindividual clinical variability in the course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is vast. We report that at least 101 of 987 patients with life-threatening coronavirus disease 2019 (COVID-19) pneumonia had neutralizing immunoglobulin G (IgG) autoantibodies (auto-Abs) against interferon-w (IFN-w) (13 patients), against the 13 types of IFN-a (36), or against both (52) at the onset of critical disease; a few also had auto-Abs against the other three type I IFNs. The auto-Abs neutralize the ability of the corresponding type I IFNs to block SARS-CoV-2 infection in vitro. These auto-Abs were not found in 663 individuals with asymptomatic or mild SARS-CoV-2 infection and were present in only 4 of 1227 healthy individuals. Patients with auto-Abs were aged 25 to 87 years and 95 of the 101 were men. A B cell autoimmune phenocopy of inborn errors of type I IFN immunity accounts for life-threatening COVID-19 pneumonia in at least 2.6% of women and 12.5% of men
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