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BACKGROUND: Asthma in the elderly (aged ≥ 65 years old) is a significant concern with high morbidity, but the pathophysiology remains unclear particularly in late-onset asthma. Recent studies suggest staphylococcal enterotoxin IgE (SE-IgE) sensitization to be a risk factor for asthma in general populations; however, the associations have not been examined in late-onset elderly asthma. OBJECTIVE: We aimed to examine the associations of SE-IgE sensitization with late-onset asthma in the elderly, using a database of elderly asthma cohort study. METHODS: A total of 249 elderly patients with asthma and 98 controls were analysed. At baseline, patients were assessed for demographics, atopy, induced sputum profiles and comorbidities including chronic rhinosinusitis (CRS). Serum total IgE and SE-IgE levels were measured. Asthma severity was assessed on the basis of asthma outcomes during a 12-month follow-up period. RESULTS: At baseline, serum SE-IgE concentrations were significantly higher in patients with asthma than in controls [median 0.16 (interquartile range 0.04-0.53) vs. 0.10 (0.01-0.19), P < 0.001]. Elderly asthma patients with high SE-IgE levels had specific characteristics of having more severe asthma, sputum eosinophilia and CRS, compared to those with lower SE-IgE levels. In multivariate logistic regression analyses, the associations between serum SE-IgE concentrations and severe asthma were significant, independently of covariables [SE-IgE-high (≥ 0.35 kU/L) vs. negative (< 0.10 kU/L) group: odds ratio 7.47, 95% confidence interval 1.86-30.03, P = 0.005]. Multiple correspondence analyses also showed that high serum SE-IgE level had close relationships with severe asthma, CRS and sputum eosinophilia together. CONCLUSIONS AND CLINICAL RELEVANCE: This is the first report on the significant associations of SE-IgE sensitization with late-onset asthma in the elderly, particularly severe eosinophilic asthma with CRS comorbidity. Our findings indicate a potential implication of SE in the high morbidity burden of elderly asthma and suggest clues to the pathogenesis of severe late-onset eosinophilic asthma in the elderly.
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Asma/inmunología , Asma/patología , Enterotoxinas/inmunología , Eosinófilos/inmunología , Eosinófilos/patología , Inmunoglobulina E/inmunología , Staphylococcus aureus/inmunología , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Especificidad de Anticuerpos/inmunología , Asma/diagnóstico , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Humanos , Inmunoglobulina E/sangre , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Pruebas de Función Respiratoria , Factores de Riesgo , Índice de Severidad de la EnfermedadRESUMEN
Two cases of hospital-acquired listeriosis were linked to a commercially produced, pasteurized ice cream mix. Manufacturers should implement safety measures from the Food Safety Modernization Act to minimize the risk of Listeria contamination. Dietary guidelines for persons at high risk of listeriosis may need revision to recognize the potential risk from pasteurized products.
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Infección Hospitalaria/microbiología , Microbiología de Alimentos , Enfermedades Transmitidas por los Alimentos/microbiología , Helados/microbiología , Listeria monocytogenes/aislamiento & purificación , Listeriosis/microbiología , Humanos , Masculino , Persona de Mediana Edad , Pasteurización , WashingtónRESUMEN
Google Trends (GT) is a Web-based surveillance tool used to explore the searching trends of specific queries on Google. Recent studies have suggested the utility of GT in predicting outbreaks of influenza and other diseases. However, this utility has not been thoroughly evaluated for allergic diseases. Therefore, we investigated the utility of GT for predicting the epidemiology of allergic rhinitis. In the USA, GT for allergic rhinitis showed repetitive seasonality that peaked in late April and early May and then rapidly decreased, and a second small peak occurred in September. These trends are highly correlated with the searching trends for other queries such as 'pollen count', antihistamines such as loratadine and cetirizine (all r > 0.88 and all P < 0.001), and even the total pollen count collected from 21 pollen counters across the USA (r = 0.928, P < 0.001). Google Trends for allergic rhinitis was similar to the monthly changes in rhinitis symptoms according to the US National Health and Nutrition Examination Survey III, sales for Claritin(®) and all over-the-counter antihistamines, and the number of monthly page views of 'claritin.com'. In conclusion, GT closely reflects the real-world epidemiology of allergic rhinitis in the USA and could potentially be used as a monitoring tool for allergic rhinitis.
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Vigilancia de la Población , Rinitis Alérgica/epidemiología , Medios de Comunicación Sociales , Australia/epidemiología , Humanos , Vigilancia de la Población/métodos , Reino Unido/epidemiología , Estados Unidos/epidemiologíaRESUMEN
Through a combination of experiment and theory we establish the possibility of achieving strong tuning of Fano resonances (FRs), by allowing their usual two-path geometry to interfere with an additional, "intruder", continuum. As the coupling strength to this intruder is varied, we predict strong modulations of the resonance line shape that, in principle at least, may exceed the amplitude of the original FR itself. For a proof-of-concept demonstration of this phenomenon, we construct a nanoscale interferometer from nonlocally coupled quantum point contacts and utilize the unique features of their density of states to realize the intruder. External control of the intruder coupling is enabled by means of an applied magnetic field, in the presence of which we demonstrate the predicted distortions of the FR. This general scheme for resonant control should be broadly applicable to a variety of wave-based systems, opening up the possibility of new applications in areas such as chemical and biological sensing and secure communications.
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We fabricated an radio frequency (RF) carbon nanotube field effect transistor (CNTFET) whose electrode shapes were standard RF designed ground-signal-ground (GSG)-type pads. The S-parameters measured from our RF CNTFET in the frequency range up to 6 GHz were fitted with an RF equivalent circuit, and the extracted gate capacitance was shown to be the capacitance value of the series combination of the electrostatic capacitance and the quantum capacitance. The effect of the channel resistance and the kinetic inductance was also discussed.
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We isolated a new mouse gene that is highly expressed in thymocytes, testis, and brain. This gene, SRG3, showed a significant sequence homology to SWI3, a yeast transcriptional activator, and its human homolog BAF155. SRG3 encodes 1,100 amino acids and has 33-47% identity with SWI3 protein over three regions. The SRG3 protein contains an acidic NH2 terminus, a myb-like DNA binding domain, a leucine-zipper motif, and a proline- and glutamine-rich region at its COOH terminus. Rabbit antiserum raised against a COOH-terminal polypeptide of the SRG3 recognized a protein with an apparent molecular mass of 155 kD. The serum also detected a 170-kD protein that seems to be a mouse homologue of human BAF170. Immunoprecipitation of cell extract with the antiserum against the mouse SRG3 also brought down a 195-kD protein that could be recognized by an antiserum raised against human SWI2 protein. The results suggest that the SRG3 protein associates with a mouse SWI2. The SRG3 protein is expressed about three times higher in thymocytes than in peripheral lymphocytes. The expression of anti-sense RNA to SRG3 mRNA in a thymoma cell line, S49.1, reduced the expression level of the SRG3 protein, and decreased the apoptotic cell death induced by glucocorticoids. These results suggest that the SRG3 protein is involved in the glucocorticoid-induced apoptosis in the thymoma cell line. This implicates that the SRG3 may play an important regulatory role during T cell development in thymus.
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Apoptosis , Proteínas de Saccharomyces cerevisiae , Linfocitos T/metabolismo , Timoma/patología , Neoplasias del Timo/patología , Transactivadores/biosíntesis , Secuencia de Aminoácidos , Animales , Linfocitos B/inmunología , Secuencia de Bases , Encéfalo/metabolismo , Clonación Molecular , Proteínas Fúngicas/química , Prueba de Complementación Genética , Humanos , Masculino , Ratones , Datos de Secuencia Molecular , Proteínas Nucleares/química , Conejos , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Represoras , Saccharomyces cerevisiae/genética , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Testículo/metabolismo , Timoma/fisiopatología , Neoplasias del Timo/fisiopatología , Transactivadores/química , Transactivadores/genética , Factores de Transcripción/química , Células Tumorales CultivadasAsunto(s)
Antimetabolitos Antineoplásicos/efectos adversos , Citarabina/efectos adversos , Desensibilización Inmunológica , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/terapia , Anciano , Antimetabolitos Antineoplásicos/administración & dosificación , Escalofríos/inducido químicamente , Citarabina/administración & dosificación , Femenino , Fiebre/inducido químicamente , Humanos , Hipotensión/inducido químicamente , Leucemia Mieloide Aguda/tratamiento farmacológico , Persona de Mediana Edad , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Tiritona , SíndromeRESUMEN
OBJECTIVE: To investigate the association between level of physical activity and poor self-rated health in Korean adults. STUDY DESIGN: A cross-sectional study was conducted on 7,800 adults aged > or =19 years who completed the Health Interview and the Health Behavior Surveys, issued during the Third National Health and Nutrition Examination Survey (2005). METHODS: The association between self-rated health and physical activity was tested using Chi-squared test. Multiple logistic regression analysis was used to calculate the odds ratios of poor self-rated health for different levels of physical activity after adjusting for physical and chronic medical conditions. RESULTS: The prevalence of poor self-rated health was significantly lower as the level of physical activity increased, and odds ratios for poor self-rated health were significantly lower for higher levels of physical activity after adjusting for age, marital status, educational status, smoking, alcohol consumption, and the number of physical impairments and chronic medical conditions. The association was similar in different age groups and among healthy respondents and respondents with physical impairments or chronic medical conditions. CONCLUSIONS: Physical activity was positively associated with self-rated health in Koreans. The independent association between a lower level of physical activity and poor self-rated health supports public health programmes that encourage regular physical activity.
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Ejercicio Físico , Conductas Relacionadas con la Salud , Estado de Salud , Adulto , Anciano , Distribución de Chi-Cuadrado , Enfermedad Crónica , Estudios Transversales , Femenino , Encuestas Epidemiológicas , Humanos , Entrevistas como Asunto , Corea (Geográfico) , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Muestreo , Factores Socioeconómicos , Adulto JovenRESUMEN
Sarcopenia, defined as loss of skeletal muscle mass and function with age, is an important health issue in aging society. We tried to investigate the relationship between blood pressure variability and skeletal muscle mass in nation-wide large population cohort. This cross-sectional study was based on data acquired in the Korea National Health and Nutrition Examination Survey (KNHANES), conducted from 2009 to 2011 by the Korean Centers for Disease Control and Prevention. We included 14,481 participants (age ≥ 20 years, male 6,302) for the analysis who had both blood pressure and whole-body dual energy X-ray absorptiometry (DXA) scan data. As an intra-individual within-visit blood pressure variability index, we calculated standard deviation (SD), coefficient of variation (CV), and maximum minus minimum BP difference (MMD) of systolic and diastolic blood pressure, which was measured 3 times. Appendicular skeletal muscle mass (ASM) was the sum of lean masses of both arms and legs. We adjusted ASM by body mass index. Significant inverse relationship was observed between blood pressure variability index (SD, CV, and MMD) and adjusted ASM. Blood pressure variability index were significantly higher in the lowest ASM quintile group both in male and female participants (p<0.001). In multivariate analysis, blood pressure variability index were significantly associated with ASM, even after adjusting confounding factors (p<0.001). In conclusion, hemodynamic influence may play an important role in the development of sarcopenia.
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Absorciometría de Fotón/métodos , Envejecimiento/fisiología , Presión Sanguínea/fisiología , Músculo Esquelético/fisiopatología , Sarcopenia/fisiopatología , Adulto , Anciano , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenAsunto(s)
Hipersensibilidad a las Drogas/etiología , Teofilina/análogos & derivados , Tioglicolatos/efectos adversos , Tiofenos/efectos adversos , Adulto , Hipersensibilidad a las Drogas/diagnóstico , Hipersensibilidad a las Drogas/inmunología , Femenino , Humanos , Activación de Linfocitos/inmunología , Pruebas del Parche/métodos , Teofilina/efectos adversos , Teofilina/inmunología , Tioglicolatos/inmunología , Tiofenos/inmunologíaRESUMEN
We investigated the efficiency droop and polarization-induced internal electric field of InGaN blue light-emitting diodes (LEDs) grown on silicon(111) and c-plane sapphire substrates. The efficiency droop of the LED sample grown on silicon substrates was considerably lower than that of the identically fabricated LED sample grown on sapphire substrates. Consequently, the LED on silicon showed higher efficiency at a sufficiently high injection current despite the lower peak efficiency caused by the poorer crystal quality. The reduced efficiency droop for the LED on silicon was attributed to its lower internal electric field, which was confirmed by reverse-bias electro-reflectance measurements and numerical simulations. The internal electric field of the multiple quantum wells (MQWs) on silicon was found to be reduced by more than 40% compared to that of the MQWs on sapphire, which resulted in a more homogenous carrier distribution in InGaN MQWs, lower Auger recombination rates, and consequently reduced efficiency droop for the LEDs grown on the silicon substrates. Owing to its greatly reduced efficiency droop, the InGaN blue LED on silicon substrates is expected to be a good cost effective solution for future lighting technology.
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We investigate the strain difference in InGaN/GaN multiple quantum wells of blue light-emitting diode (LED) structures grown on silicon(1 11) and c-plane sapphire substrates by comparing the strength of piezo-electric fields in MQWs. The piezo-electric fields for two LED samples grown on silicon and sapphire substrates are measured by using the reverse-bias electro-reflectance (ER) spectroscopy. The flat-band voltage is obtained by measuring the applied reverse bias voltage that induces a phase inversion in the ER spectra, which is used to calculate the strength of piezo-electric fields. The piezo-electric field is determined to be 1.36 MV/cm for the LED on silicon substrate and 1.83 MV/cm for the LED on sapphire substrate. The ER measurement results indicate that the strain-induced piezo-electric field is greatly reduced in the LED grown on silicon substrates consistent with previous strain measurement results by micro-Raman spectroscopy and high-resolution transmission electron microscopy.
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We compare the strain states and device performances of GaN-based blue light-emitting diodes (LEDs) grown on Si(111) and sapphire substrates. The strain characteristics are investigated using micro-Raman spectroscopy and high-resolution transmission electron microscopy. These analyses reveal that GaN layer grown on Si has a residual tensile strain in contrast to a compressive strain for GaN on sapphire, and quantum wells (QWs) on GaN/Si experience reduced lattice mismatch than those of GaN/sapphire. When external quantum efficiencies of LED on sapphire and Si substrates are compared, the LED on Si shows better efficiency droop characteristics and this is attributed to a decrease in piezo-electric field strength in InGaN/GaN layers owing to reduced lattice mismatch.
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In this correspondence, a constrained least-squares multichannel image restoration approach is proposed, in which no prior knowledge of the noise variance at each channel or the degree of smoothness of the original image is required. The regularization functional for each channel is determined by incorporating both within-channel and cross-channel information. It is shown that the proposed smoothing functional has a global minimizer.
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The determination of the regularization parameter is an important issue in regularized image restoration, since it controls the trade-off between fidelity to the data and smoothness of the solution. A number of approaches have been developed in determining this parameter. In this paper, a new paradigm is adopted, according to which the required prior information is extracted from the available data at the previous iteration step, i.e., the partially restored image at each step. We propose the use of a regularization functional instead of a constant regularization parameter. The properties such a regularization functional should satisfy are investigated, and two specific forms of it are proposed. An iterative algorithm is proposed for obtaining a restored image. The regularization functional is defined in terms of the restored image at each iteration step, therefore allowing for the simultaneous determination of its value and the restoration of the degraded image. Both proposed iteration adaptive regularization functionals are shown to result in a smoothing functional with a global minimum, so that its iterative optimization does not depend on the initial conditions. The convergence of the algorithm is established and experimental results are shown.
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The efficiency of shape coding is an important problem concerning content-based image manipulations and object-based coding of the video sequences. In order to encode the shape information of an object, the boundary is approximated by a polygon which can be encoded with the smallest number of bits for maximum allowable distortion. The conventional boundary coding schemes, however, does not successfully remove the temporal redundancy of the video sequences. This paper proposes a new boundary encoding scheme by which the temporal redundancy between two successive frames is efficiently removed, resulting in lower bit-rate than the conventional algorithms. The interframe vertex selection problem is solved by finding the path with the minimum cost in the directed acyclic graph (DAG) and its fast version using a simplified graph is introduced to reduce the computational load. The vertices were selected from both the current frame to be encoded and the previous frame already encoded, and thus, the temporal redundancy was effectively removed.
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When approximating the shape of a region, a fixed bound on the tolerable distortion is set for approximating its contour points. An adaptive approximation bound for lossy coding of the contour points is proposed. A function representing the relative significance of the contour points is defined to adjust the distortion bound along the region contour allowing an adaptive approximation of the region shape. The effectiveness of the adaptive contour coding approach for a region-based coding system is verified through experiments.
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Magneto-transport measurements are performed on two-dimensional GaAs electron systems to probe the quantum Hall (QH) effect at low magnetic fields. Oscillations following the Shubnikov-de Haas (SdH) formula are observed in the transition from the insulator to QH liquid when the observed almost temperature-independent Hall slope indicates insignificant interaction correction. Our study shows that the existence of SdH oscillations in such a transition can be understood based on the non-interacting model.
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Modelos Químicos , Oscilometría/métodos , Soluciones/química , Soluciones/efectos de la radiación , Simulación por Computador , Conductividad Eléctrica , Campos Magnéticos , Ensayo de Materiales , Teoría CuánticaRESUMEN
We demonstrate a hybrid process for fabricating one-dimensional wire devices. The process is a combination of an alignment procedure using dielectrophoresis and subsequent contact metal formation utilizing electrochemical deposition with non-toxic organic-based Au electrolytes. Several devices have been successfully made from GaN nanowires or multi-walled carbon nanotubes (MWCNTs) using our hybrid technique. We demonstrate that rapid thermal annealing improves the ohmic characteristics by five orders of magnitude in the case of the GaN devices and â¼300% in the case of the MWCNT devices. One of the reasons for this improvement is enhanced gold wetting due to the reduction of grain size at the annealing temperature.
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Xenopus laevis oocytes undergo an increase in intracellular pH (pHi) from 7.2 to 7.7 due to the up-regulation of Na+/H+ antiporters in their plasma membrane during oocyte meiotic maturation. Up-regulation of Na+/H+ exchangers (NHE) found in other cell systems appears to be controlled, in some cases, by direct phosphorylation of the exchanger. A number of active protein kinases can be found in maturing Xenopus oocytes. These include, c-mos kinase, Raf-1 kinase, mitogen-activated kinase kinase (MAPKK), MAPK, ribosomal S6 kinase (RSK), and histone H-1 kinase. Our previous study indicated that c-mos kinase, was involved in regulating the increase in oocyte pHi. In the current study, we show that when mRNA coding for a constitutively active form of Raf-1 kinase (delta N-Raf-1) was microinjected into oocytes, the protein product induced an increase in oocyte pHi. On the contrary, the injection of mRNA coding for wild-type Raf-1 (WT-Raf-1) or a kinase-deficient form of Raf-1 (KD-Raf-1) had no effect on the recipient oocyte pHi. 8-Br-cAMP and forskolin blocked the increase in pHi during oocyte meiotic maturation, but had no effect on the Raf-1-induced increase in oocyte pHi. Studies using antisense c-mos oligos demonstrated that Raf-1 was not working via a feedback loop to endogenous c-mos mRNA within the recipient oocytes. Experiments using the selective MAPKK inhibitor, PD 98059, indicated that the Raf-1 effect on oocyte pHi was not mediated by the downstream kinase, MAPKK. Therefore, Raf-1 appears to act independently of c-mos kinase in a pathway, not involving MAPKK, leading to the up-regulation of the Na+/H+ antiporters in Xenopus oocytes.