Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
1.
Rev Neurol ; 79(2): 41-49, 2024 Jul 16.
Artigo em Espanhol | MEDLINE | ID: mdl-38976583

RESUMO

INTRODUCTION: The increase in the number of people with upper limb spasticity as a sequela of cerebrovascular disease, which negatively impacts their autonomy, functional independence and participation, and affects their quality of life, calls for the application of precise and objective instruments for its measurement and evaluation. OBJECTIVE: To assess the validity and reliability of the Tardieu scale in the evaluation of upper extremity spasticity in adults with cerebrovascular disease. MATERIALS AND METHODS: The search strategy was implemented in eight databases; the systematic review protocol was registered beforehand in INPLASY (with registration no. 2023110076). The evidence was synthesised in three phases: a tabular presentation of results, an evaluation of the quality of the articles, and a narrative synthesis of the findings. RESULTS: Only three of the 33 articles identified fulfilled the variables that enable the validity and reliability of the Tardieu scale to be established. The measurements of angles and velocities R1, R2 and R2-R1 were analysed. Student's t-test to assess the reliability between the measurements of R1 and R2; and angles R2 and R2-R1 showed statistical significance, which confirmed the reliability of the scale. CONCLUSIONS: The Tardieu scale proved robust. It is important to note that the sample size, the time of evolution of the disease and the age of the patients may influence the results of the scale.


TITLE: Validez y fiabilidad de la escala de Tardieu para evaluar la espasticidad en miembro superior en adultos con enfermedad cerebrovascular. Revisión sistemática.Introducción. El incremento en el número de personas con espasticidad en los miembros superiores como secuela de una enfermedad cerebrovascular, que impacta negativamente en la autonomía, la independencia funcional y la participación, y afecta a la calidad de vida de las personas, demanda la aplicación de herramientas clínicas precisas y objetivas para su medición y evaluación. Objetivo. Evaluar la validez y la fiabilidad de la escala de Tardieu en la evaluación de la espasticidad en las extremidades superiores de adultos con enfermedad cerebrovascular. Materiales y métodos. La estrategia de búsqueda se implementó en ocho bases de datos; el protocolo de revisión sistemática se registró previamente en INPLASY (registro n.o 2023110076). La síntesis de la evidencia se llevó a cabo en tres fases: presentación tabular de resultados, evaluación de la calidad de los artículos y síntesis narrativa de los hallazgos. Resultados. De los 33 artículos identificados, sólo tres cumplieron con las variables que permiten establecer la validez y la fiabilidad de la escala de Tardieu. Se analizaron las medidas de los ángulos y velocidades R1, R2 y R2-R1. La prueba de la t de Student para evaluar la fiabilidad entre las medidas de R1 y R2; los ángulos R2 y R2-R1 mostraron significancia estadística, lo que confirmó la confiabilidad de la escala. Conclusiones. La escala de Tardieu demostró robustez. Es importante considerar que el tamaño de la muestra, el tiempo de evolución de la enfermedad y la edad de los pacientes pueden influir en los resultados de la escala.


Assuntos
Transtornos Cerebrovasculares , Espasticidade Muscular , Extremidade Superior , Humanos , Espasticidade Muscular/etiologia , Espasticidade Muscular/diagnóstico , Espasticidade Muscular/fisiopatologia , Reprodutibilidade dos Testes , Transtornos Cerebrovasculares/complicações , Extremidade Superior/fisiopatologia , Adulto
2.
J Phys Condens Matter ; 36(35)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38776954

RESUMO

Ordered and disordered semiconductor superlattices represent structures with completely opposed properties. For instance, ordered superlattices exhibit extended Bloch-like states, while disordered superlattices present localized states. These characteristics lead to higher conductance in ordered superlattices compared to disordered ones. Surprisingly, disordered dimer superlattices, which consist of two types of quantum wells with one type always appearing in pairs, exhibit extended states. The percentage of dissimilar wells does not need to be large to have extended states. Furthermore, the conductance is intermediate between ordered and disordered superlattices. In this work, we explore disordered dimer superlattices in graphene. We calculate the transmission and transport properties using the transfer matrix method and the Landauer-Büttiker formalism, respectively. We identify and discuss the main energy regions where the conductance of random dimer superlattices in graphene is intermediate to that of ordered and disordered superlattices. We also analyze the resonant energies of the double quantum well cavity and the electronic structure of the host gated graphene superlattice (GGSL), finding that the coupling between the resonant energies and the superlattice energy minibands gives rise to the extended states in random dimer GGSLs.

3.
J Phys Condens Matter ; 36(6)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37903438

RESUMO

Gaussian and Gaussian-related structures are quite attractive due to its versatility to modulate the electronic transport, including its possibility as electron filters. Here, we show that these non-conventional profiles are not the exception when dealing with Fermi velocity barriers in monolayer graphene. In particular, we show that Gaussian Fermi velocity graphene barriers (G-FVGBs) and Gaussian-pulsed-like Fermi velocity graphene superlattices (GPL-FVGSLs) can serve as electron band-pass filters and oscillating conductance structures. We reach this conclusion by theoretically studying the transmission and transport properties of the mentioned structures. The study is based on the continuum model, the transfer matrix method and the Landauer-Büttiker formalism. We find nearly flat transmission bands or pass bands for G-FVGBs modulable through the system parameters. The pass bands improve as the maximum ratio of Fermi velocities (ξmax) increases, however its omnidirectional range is reduced. These characteristics result in a decaying conductance (integrated transmission) withξmax. The integrated transmission remains practically unaltered with the size of the system due to the saturation of the electron pass band filtering. In the case of GPL-FVGSLs the GPL profile results in regions of high transmission probability that can merge as flat transmission minibands if the pulse fraction and the superlattice parameters are appropriately tuned. The GPL profile also results in conductance (integrated transmission) oscillations that can be multiplied or reduced in number by adjusting the pulse fraction as well as the superlattice parameters.

4.
Nanotechnology ; 32(9): 095202, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33126229

RESUMO

Solution-processed photodetectors have emerged as the next generation of sensing technology owing to their ease of integration with electron devices and of tuning photodetector performance. Currently, novel self-powered photodetectors without an external power source, for use in sensing, imaging and communication, are in high demand. Herein, we successfully developed a self-powered photodetector based on a novel solution-processed p-NiO/n-CdS:Al heterojunction, which shows an excellent current rectification characteristic ratio of up to three orders in the dark and distinctive photovoltaic behavior under light illumination. The complete solution synthesis route followed the development of CdS:Al thin films on ITO substrates by chemical bath deposition and NiO thin films by the sol-gel route. Optical absorption data revealed that NiO is more active in the UV region and CdS:Al has a majority of absorption in the visible region; so, upon light illumination, the effective separation of photogenerated carriers produces fast photodetection in the UV-visible region. The photoresponsivity values of the fabricated device were calculated to be 55 mA W-1 and 30 mA W-1 for UV and visible illumination, respectively. Also, the device has a fast rise and decay photoresponse speed at zero bias voltage, due to the self-driven photovoltaic effect which makes this heterojunction a self-powered device. This complete solution and new method of fabrication make it possible to combine different materials and flexible substrates, enhancing its potential applications in photodetectors, optoelectronic devices and sensors.

5.
Materials (Basel) ; 13(3)2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32033379

RESUMO

The effect of α-Al2O3 nanoparticles (up to 5 wt.%) on the physical, mechanical, and thermal properties, as well as on the microstructural evolution of a dense magnesia refractory is studied. Sintering temperatures at 1300, 1500, and 1600 °C are used. The physical properties of interest were bulk density and apparent porosity, which were evaluated by the Archimedes method. Thermal properties were examined by differential scanning calorimetry. The mechanical behavior was studied by cold crushing strength and microhardness tests. Finally, the microstructure and mineralogical qualitative characteristics were studied by scanning electron microscopy and X-ray diffraction, respectively. Increasing the sintering temperature resulted in improved density and reduced apparent porosity. However, as the α-Al2O3 nanoparticle content increased, the density and microhardness decreased. Microstructural observations showed that the presence of α-Al2O3 nanoparticles in the magnesia matrix induced the magnesium-aluminate spinel formation (MgAl2O4), which improved the mechanical resistance most significantly at 1500 °C.

6.
Sci Rep ; 9(1): 17772, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31780693

RESUMO

We identify different schemes to enhance the violation of Leggett-Garg inequalities in open many-body systems. Considering a nonequilibrium archetypical setup of quantum transport, we show that particle interactions control the direction and amplitude of maximal violation, and that in the strongly-interacting and strongly-driven regime bulk dephasing enhances the violation. Through an analytical study of a minimal model we unravel the basic ingredients to explain this decoherence-enhanced quantumness, illustrating that such an effect emerges in a wide variety of systems.

7.
Acta Ortop Mex ; 33(4): 256-260, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-32246598

RESUMO

BACKGROUNDS: The isolated fracture/dislocation of the cuneiform bones is a not very frequent event and only a few cases have been reported in the literature. This type of event is presented as a variation of the Lisfranc injuries. The present report shows a rare clinical case of a patient with dislocation of the first and second cuneiform bones and fracture in situ of the third cuneiform bone of the left foot. CASE REPORT: A 49-year-old female patient presented severe traumatism of the dorsum of the foot with bony and soft tissue exposure as a result of a car accident. The patient underwent surgery in the emergency department consisting of surgical cleaning, debridement, reduction of dislocation of the first and second cuneiform bones and percutaneous fixation with 2.0 mm Kirschner wires. RESULTS: After the surgery, the patient was found to be in good general condition, oriented without pain, stable, conscious, without traces of active bleeding from the wound and with the presence of Kirschner wires in an appropriate position. DISCUSSION: An exhaustive inspection of the injury is recommended through the analysis of X-ray images, CT scans or magnetic resonance imaging, especially in unexposed lesions in order to apply the appropriate treatment and be able to achieve a prompt recovery of the patient.


ANTECEDENTES: La fractura y la luxación aislada de los huesos cuneiformes son un evento no muy frecuente y sólo pocos casos han sido reportados en la literatura. Este tipo de eventos se presenta como una variación de las lesiones de Lisfranc. El presente reporte muestra un caso clínico poco frecuente de un paciente con luxación de la primera y segunda cuña y fractura in situ de la tercera cuña del pie izquierdo. CASO CLÍNICO: Mujer de 49 años de edad, que presentó traumatismo severo del dorso del pie con exposición de tejido óseo y blando como consecuencia de atropellamiento. La paciente fue sometida a cirugía en el Servicio de Urgencias, donde se realizó aseo quirúrgico, desbridamiento, reducción de la luxación de la primera y segunda cuña y fijación percutánea con clavillos Kirschner de 2.0 mm. RESULTADOS: Posterior a la cirugía, la paciente se reportó con buen estado en general, orientada, sin facie de dolor, estable, consciente, sin huellas de sangrado activo por la herida y con presencia de clavillos Kirschner en adecuada posición. DISCUSIÓN: Se recomienda una inspección exhaustiva de la lesión a través del análisis de las imágenes de rayos X, tomografía computarizada o imágenes de resonancia magnética, especialmente en lesiones no expuestas, pues con ello se puede aplicar el tratamiento adecuado y lograr una pronta recuperación del paciente.


Assuntos
Fraturas Ósseas , Luxações Articulares , Ossos do Tarso , Fios Ortopédicos , Feminino , , Fraturas Ósseas/cirurgia , Humanos , Luxações Articulares/cirurgia , Pessoa de Meia-Idade , Ossos do Tarso/lesões
8.
Rev. mex. ing. bioméd ; 38(1): 7-18, ene.-abr. 2017. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-902325

RESUMO

Resumen: La existencia de una correlación entre la frecuencia cardíaca (FC), la frecuencia respiratoria (FR) y las respuestas electrodérmicas de la piel (Skin Conductance Response, SCR) ha sido reportada en la literatura, así como también el uso de estos parámetros como medida del nivel de activación del sistema nervioso autónomo. Objetivo: Este trabajo presenta una herramienta (SCRATER) para el análisis conjunto de SCR, FC y FR, las dos últimas, calculadas a partir del análisis del registro de electrocardiograma (ECG). Metodología: En esta investigación, se realizó una descripción detallada de cada algoritmo desarrollado, asi como una una descripción de la interfaz para utilizarlos. En la validación de los algoritmos empleados, se analizaron 192 registros de ECG y 231 registros de actividad electrodérmica (Electro-Dermal Activity, EDA) de 40 participantes masculinos sanos, de los cuales se calculó el número de complejos QRS y FC en cada registro de ECG y el número de SCRs de cada registro de EDA. Resultados: Los datos obtenidos fueron comparados con otras herramientas que analizan SCR y FC pero de manera independiente, obteniendo resultados equiparables mediante coeficientes de correlación. Limitaciones: El ruido y los artefactos presentes en los registros no permiten una correcta estimación de los parámetros y afectan los resultados de todas las herramientas empleadas en el desarrollo de este trabajo. Valor: SCRATER ofrece tres ventajas principales sobre las otras herramientas: 1) libre acceso, 2) código abierto y no utiliza formatos codificados o exclusivos. Conclusión: Este trabajo proporciona una herramienta computacional gratuita que permite analizar simultáneamente SCRs, FC y FR.


Abstract: The existence of a correlation between heart rate (HR), respiratory rate (RR) and skin conductance response (SCR) has been reported in the literature, as well as the use of these parameters as a measure of the activation level of the autonomous nervous system. Objective: This paper introduces a computational tool (SCRATER) developed with the aim to analyze simultaneous recordings of SCR, and heart and respiratory rates, which were calculated from the electrocardiogram recording (ECG) analysis. Methodology: In this research, a detailed description of each developed algorithm was made, as well as a description of the interface to be used. In the validation of the algorithms used, 192 ECG records and 231 Electro-Dermal Activity (EDA) registers of 40 healthy male participants were analyzed, from which the number of QRS complexes and HR in each ECG record and the number of SCRs of each EDA record are calculated. Results: The data obtained were compared with other tools that analyze SCR and HR separately, obtaining comparable results using correlation coefficients. Limitations: The noise and artifacts present in the records do not allow a correct estimation of the parameters and affect the results of all the tools used in the development of this work. Value: SCRATER offers three main advantages over other tools: 1) free access, 2) open source and 3) does not use coded or exclusive formats. Conclusion: This work provides a free computational tool that allows simultaneous analysis of SCRs, FC and FR.

9.
J Thromb Haemost ; 13(7): 1274-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25980766

RESUMO

BACKGROUND: No studies have identified which patients with upper-extremity deep vein thrombosis (DVT) are at low risk for adverse events within the first week of therapy. METHODS: We used data from Registro Informatizado de la Enfermedad TromboEmbólica to explore in patients with upper-extremity DVT a prognostic score that correctly identified patients with lower limb DVT at low risk for pulmonary embolism, major bleeding, or death within the first week. RESULTS: As of December 2014, 1135 outpatients with upper-extremity DVT were recruited. Of these, 515 (45%) were treated at home. During the first week, three patients (0.26%) experienced pulmonary embolism, two (0.18%) had major bleeding, and four (0.35%) died. We assigned 1 point to patients with chronic heart failure, creatinine clearance levels 30-60 mL min(-1) , recent bleeding, abnormal platelet count, recent immobility, or cancer without metastases; 2 points to those with metastatic cancer; and 3 points to those with creatinine clearance levels < 30 mL min(-1) . Overall, 759 (67%) patients scored ≤ 1 point and were considered to be at low risk. The rate of the composite outcome within the first week was 0.26% (95% confidence interval [CI] 0.004-0.87) in patients at low risk and 1.86% (95% CI 0.81-3.68) in the remaining patients. C-statistics was 0.73 (95% CI 0.57-0.88). Net reclassification improvement was 22%, and integrated discrimination improvement was 0.0055. CONCLUSIONS: Using six easily available variables, we identified outpatients with upper-extremity DVT at low risk for adverse events within the first week. These data may help to safely treat more patients at home.


Assuntos
Técnicas de Apoio para a Decisão , Pacientes Ambulatoriais , Embolia Pulmonar/etiologia , Trombose Venosa Profunda de Membros Superiores/etiologia , Adulto , Idoso , Anticoagulantes/efeitos adversos , Canadá , Europa (Continente) , Feminino , Hemorragia/induzido quimicamente , Humanos , Israel , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/mortalidade , Embolia Pulmonar/prevenção & controle , Sistema de Registros , Medição de Risco , Fatores de Risco , América do Sul , Fatores de Tempo , Resultado do Tratamento , Trombose Venosa Profunda de Membros Superiores/diagnóstico , Trombose Venosa Profunda de Membros Superiores/mortalidade , Trombose Venosa Profunda de Membros Superiores/terapia
10.
Diaeta (B. Aires) ; 33(151): 14-20, abril. 2015. graf
Artigo em Espanhol | LILACS | ID: lil-766759

RESUMO

El consumo de suplementos nutricionales (SN) se ha investigado generalmente en relación al rendimiento deportivo. Menos información existe en relación a población no deportista pero físicamente activa. Objetivo y metodología: El objetivo fue conocer las características de los consumidores de SN en 412 usuarios (179 mujeres) de gimnasios de cuatro ciudades del sur de Chile. El instrumento utilizado para recolectar datos correspondió a un cuestionario previamente validado (1), estructurado con preguntas cerradas, alternativas y preguntas abiertas en relación al consumo de SN. Para su interpretación se utilizaron estadísticos descriptivos y de comparación (i.e. Chi cuadrado). El nivel de significancia estadística se estableció en p<0,05. Resultados: los resultados revelan que 22% de los usuarios consumen SN. De los hombres consumidores, 37% lo realiza para aumentar masa muscular y 36% para mejorar el rendimiento físico. Entre las mujeres, 32% los consume por motivos relacionados a salud. Los SN más consumidos fueron: proteínas (36%), vitaminas y minerales (11%), creatina (10%), aminoácidos y carbohidratos (8%). En cuanto al perfil del consumidor, está representado por jóvenes de entre 15 a 25 años, dedicados en su mayoría al estudio y al trabajo, con menos de un año de asistencia al gimnasio y una frecuencia de asistencia ≥ 3 sesiones/semana. Conclusión: un relativamente bajo consumo de SN fue observado,en comparación con deportistas, influenciado por la edad,el género y el uso de dieta o alimentación especial. Varones jóvenes (i.e. 15 a 25 años de edad) que trabajan, con una alta frecuencia de asistencia a gimnasios (≥ 3 sesiones/semana) son los principales consumidores de SN...


Assuntos
Humanos , Chile , Dieta , Suplementos Nutricionais , Ginástica
11.
Phys Rev Lett ; 112(3): 030403, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24484124

RESUMO

We reveal universal dynamical scaling behavior across adiabatic quantum phase transitions in networks ranging from traditional spatial systems (Ising model) to fully connected ones (Dicke and Lipkin-Meshkov-Glick models). Our findings, which lie beyond traditional critical exponent analysis and adiabatic perturbation approximations, are applicable even where excitations have not yet stabilized and, hence, provide a time-resolved understanding of quantum phase transitions encompassing a wide range of adiabatic regimes. We show explicitly that even though two systems may traditionally belong to the same universality class, they can have very different adiabatic evolutions. This implies that more stringent conditions need to be imposed than at present, both for quantum simulations where one system is used to simulate the other and for adiabatic quantum computing schemes.

12.
Br J Cancer ; 108(11): 2334-8, 2013 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-23695017

RESUMO

BACKGROUND: Allergies have been described as protective factors against the development of childhood acute leukaemia (AL). Our objective was to investigate the associations between allergy history and the development of AL and acute lymphoblastic leukaemia (ALL) in children with Down syndrome (DS). METHODS: A case-control study was performed in Mexico City. The cases (n=97) were diagnosed at nine public hospitals, and the controls (n=222) were recruited at institutions for children with DS. Odds ratios (OR) were calculated. RESULTS: Asthma was positively associated with AL development (OR=4.18; 95% confidence interval (CI): 1.47-11.87), whereas skin allergies were negatively associated (OR=0.42; 95% CI: 0.20-0.91). CONCLUSION: Our findings suggest that allergies and AL in children with DS share biological and immune mechanisms. To our knowledge, this is the first study reporting associations between allergies and AL in children with DS.


Assuntos
Síndrome de Down/epidemiologia , Hipersensibilidade/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Estudos de Casos e Controles , Criança , Feminino , Humanos , Modelos Logísticos , Masculino , México/epidemiologia
13.
Opt Express ; 20(4): 4470-83, 2012 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-22418206

RESUMO

The dependence of the excitonic two-photon absorption on the quantum correlations (entanglement) of exciting biphotons by a semiconductor quantum well is studied. We show that entangled photon absorption can display very unusual features depending on space-time-polarization biphoton parameters and absorber density of states for both bound exciton states as well as for unbound electron-hole pairs. We report on the connection between biphoton entanglement, as quantified by the Schmidt number, and absorption by a semiconductor quantum well. Comparison between frequency-anti-correlated, unentangled and frequency-correlated biphoton absorption is addressed. We found that exciton oscillator strengths are highly increased when photons arrive almost simultaneously in an entangled state. Two-photon-absorption becomes a highly sensitive probe of photon quantum correlations when narrow semiconductor quantum wells are used as two-photon absorbers.

14.
Meat Sci ; 79(3): 541-8, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22062915

RESUMO

The concentrations of fatty acids were measured in total lipids, triacyglycerol and phospholipid fractions of intramuscular fat (IMF) from the Longissimus dorsi (LD) muscle of 10 lambs reared to approximately 30kg live weight on natural pasture with their dams. Fatty acid composition was also measured in 25 (five of each) Semitendinosus (ST), Semimembranosus (SM), Rectus femoris (RF), Gluteus (GLU) and Tensor fascia latea (TFL) muscles. Intramuscular fat percentages were similar for all muscles. Aspects of the fatty-acid patterns of relevance to human nutrition tended to favor the leg muscles with lower saturated fatty acids (SFA %), n-6/n-3 fatty acid ratios (p<0.01) and higher concentrations of the conjugated linoleic acid (CLA) (p<0.05). The estimated fatty acid concentrations (mg/100g of meat) showed higher contribution of arachidonic (C20:4 n-6), eicosapentanoic (C20:5 n-3), docosapentanoic (C22:5 n-3) and docosahexanoic (C22:6 n-3) acids in leg compared to LD lipids.

15.
J Food Sci ; 72(4): E190-6, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17995771

RESUMO

Alginate- (2% w/v) or gellan-based (0.5%) edible films, containing glycerol (0.6% to 2.0%), N-acetylcysteine (1%), and/or ascorbic acid (1%) and citric acid (1%), were formulated and used to coat fresh-cut apple and papaya cylinders. Water vapor permeability (WVP) was significantly higher (P < 0.05) in alginate films (0.30 to 0.31 x 10(-9) g m/Pa s m2) than in the gellan ones (0.26 to 0.27 x 10(-9) g m/Pa s m2). Addition of 0.025% (w/v) sunflower oil decreased WVP of gellan films (0.20 to 0.22 x 10(-9) g m/Pa s m2). Water solubility of gellan and alginate films at 25 degrees C (0.47 to 0.59 and 0.74 to 0.79, respectively) and their swelling ratios (2.3 to 2.6 and 1.6 to 2.0, respectively) indicate their potential for coating high moisture fresh-cut fruits. Fresh-cut apple and papaya cylinders were successfully coated with 2% (w/v) alginate or gellan film-forming solutions containing viable bifidobacteria. WVP in alginate (6.31 and 5.52 x 10(-9) g m/Pa s m2) or gellan (3.65 and 4.89 x 10(-9) g m/Pa s m2) probiotic coatings of papaya and apple, respectively, were higher than in the corresponding cast films. The gellan coatings and films exhibited better water vapor properties in comparison with the alginate coatings. Values > 10(6) CFU/g B. lactis Bb-12 were maintained for 10 d during refrigerated storage of fresh-cut fruits, demonstrating the feasibility of alginate- and gellan-based edible coatings to carry and support viable probiotics on fresh-cut fruit.


Assuntos
Alginatos/farmacologia , Antibacterianos/farmacologia , Conservação de Alimentos/métodos , Frutas/microbiologia , Polissacarídeos Bacterianos/farmacologia , Probióticos , Acetilcisteína , Alginatos/administração & dosagem , Antibacterianos/administração & dosagem , Ácido Ascórbico , Bifidobacterium/crescimento & desenvolvimento , Carica , Ácido Cítrico , Estudos de Viabilidade , Manipulação de Alimentos/métodos , Ácido Glucurônico/administração & dosagem , Ácido Glucurônico/farmacologia , Glicerol , Ácidos Hexurônicos/administração & dosagem , Ácidos Hexurônicos/farmacologia , Malus , Permeabilidade , Óleos de Plantas , Polissacarídeos Bacterianos/administração & dosagem , Refrigeração , Solubilidade , Óleo de Girassol , Propriedades de Superfície , Volatilização , Água
16.
Artigo em Inglês | MEDLINE | ID: mdl-18003043

RESUMO

This work proposes the clino-ortho maneuver to analyze the metabolic energy expenditure variability by Indirect Calorimetry (IC). This analysis uses a hybrid calorimeter which includes simultaneously the mixing-chamber (MC) and the breath by breath (BbB) IC techniques. VO2 and VCO2 short-term variability was characterized as metabolic variability in the MC technique by intra-group standard deviation averages. When the BbB technique was used the metabolic variability characterization was done by VO2 and VCO2 discrete time series power spectrum analysis in the 0-0.5 Hz band. Thus a statistical population of 17 young healthy volunteers was studied using a clino-ortho maneuver with 30-30 minutes in each position after 8 hours of fasting. The results showed an energy expenditure change of 40% in Kcal/day (p<0.01). The metabolic variability was partially significant using the MC technique while BbB total power spectrum changed from 35 to 60 for the VO2 and from 24 to 37 for the VCO2 (ml/bth)(2), (p<0.05) in the region from 0 to 0.04 Hz. It was concluded that using this new measurement technique and the clino-ortho maneuver metabolic variability information not yet studied was revealed.


Assuntos
Testes Respiratórios/instrumentação , Testes Respiratórios/métodos , Adolescente , Adulto , Índice de Massa Corporal , Calorimetria Indireta , Dióxido de Carbono/análise , Desenho de Equipamento , Frequência Cardíaca , Humanos , Modelos Biológicos , Oxigênio/análise , Consumo de Oxigênio , Valores de Referência
17.
Clin Neuropathol ; 26(3): 111-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-19157002

RESUMO

OBJECTIVE: Meningiomas involving the pineal region are rare. Herein we describe two cases of chordoid meningioma with histologic evidence of pineal gland infiltration. MATERIALS AND METHODS: Clinical histories were abstracted from chart review and consultation letters. HE-stained slides were reviewed in both cases. Selected immunohistochemical stains were performed. RESULTS: the patients included a 44-year-old male and a 37-year-old female who presented with symptoms of intracranial tumor referable to the pineal region. On magnetic resonance imaging (MRI), both lesions demonstrated heterogeneous contrast enhancement. Histologically, the tumors were characterized by strands and cords ofmeningothelial cells arranged in a mucinous stroma. In addition, obvious meningothelial cytology as well as focal osseous metaplasia (Case 1), and transitional histology (Case 2) were also noted. Tumor cells demonstrated EMA and focal S100 protein immunoreactivity, but lacked cytokeratin AE1/AE3 and glial fibrillary acidic protein (GFAP) staining. Synaptophysin and neurofilament protein highlighted the overrun pineal gland parenchyma. MIB1-proliferative index was 8.4 and 20.1%, respectively. CONCLUSIONS: Chordoid meningioma, although rare, may occur in the pineal region. The differential diagnosis of this meningioma subtype in this location is discussed.


Assuntos
Neoplasias Meníngeas/patologia , Meningioma/patologia , Glândula Pineal/patologia , Adulto , Neoplasias Encefálicas/patologia , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Masculino , Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo
18.
Eur J Ophthalmol ; 16(5): 733-40, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17061226

RESUMO

PURPOSE: Vitreomacular traction syndrome (VMTS) and full-thickness macular hole are two different well-known entities that on follow-up may be subjected to clinical modifications. Precisely, a spontaneous separation of idiopathic VMTS occurred in three eyes of three patients relieving in addition traction of the posterior hyaloid that had led also to a focal macular retinal pigment epithelial detachment (RPE). An association to a full-thickness macular hole was observed in the contralateral eye of one of the patients. METHODS: This is a retrospective study of three patients evaluated with fluorescein angiography and documented with optical coherence tomography using the Stratus (OCT) model 3000, with scans analysis and protocols analysis, measuring the size and shape of vitreomacular adhesions, macular thickness changes before and after the spontaneous separation of the tractional posterior hyaloid adhesion. In addition, the vitreous was evaluated with contact lens slit lamp biomicroscopy and ultrasound. The associated contralateral macular hole in one of the patients was surgically treated. RESULTS: Two of the three eyes with spontaneous separation of the VMTS recovered 20/25 central visual acuity; the other eye maintained the initial 20/50 visual acuity. The treated macular hole recovered 20/100 corrected visual acuity. CONCLUSIONS: Spontaneous separation of posterior hyaloid is a possible outcome during follow-up of idiopathic VMTS that can be well evaluated and documented with OCT while macular fluorescein angiography may be silent in cases like these presently reported. Central vision recovery can be excellent following the spontaneous separation, which releases anterior-posterior traction including on the retinal pigment epithelium and decreases macular thickness as measured with OCT. Therefore, regarding management, the indication for vitrectomy should be delayed awaiting the spontaneous release of vitreomacular traction in 4 to 6 months. The association between idiopathic VMTS in one eye and full-thickness macular hole in the opposite eye of one patient is an important pathophysiologic consideration.


Assuntos
Macula Lutea/patologia , Perfurações Retinianas/complicações , Descolamento do Vítreo/complicações , Idoso , Diagnóstico Diferencial , Feminino , Angiofluoresceinografia , Seguimentos , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Perfurações Retinianas/patologia , Estudos Retrospectivos , Síndrome , Tomografia de Coerência Óptica , Resultado do Tratamento , Acuidade Visual , Descolamento do Vítreo/patologia
19.
Br J Ophthalmol ; 89(11): 1423-6, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16234445

RESUMO

UNLABELLED: AMS: To describe the characteristics and surgical outcomes of full thickness macular hole surgery after laser assisted in situ keratomileusis (LASIK) for the correction of myopia. METHODS: 13 patients (14 eyes) who developed a macular hole after bilateral LASIK for the correction of myopia participated in the study. RESULTS: Macular hole formed 1-83 months after LASIK (mean 13 months). 11 out of 13 (84.6%) patients were female. Mean age was 45.5 years old (25-65). All eyes were myopic (range -0.50 to -19.75 dioptres (D); mean -8.4 D). Posterior vitreous detachment (PVD) was not present before and was documented after LASIK on 42.8% of eyes. Most macular hole were unilateral, stage 4 macular hole, had no yellow deposits on the retinal pigment epithelium, had no associated epiretinal membrane, were centric, and had subretinal fluid. The mean diameter of the hole was 385.3 microm (range 200--750 microm). A vitrectomy closed the macular hole on all eyes with an improvement on final best corrected visual acuity (VA) on 13 out of 14 (92.8%) patients. CONCLUSIONS: This study shows that vitreoretinal surgery can be successful in restoring vision for most myopic eyes with a macular hole after LASIK.


Assuntos
Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Miopia/cirurgia , Perfurações Retinianas/etiologia , Perfurações Retinianas/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Perfurações Retinianas/fisiopatologia , Resultado do Tratamento , Acuidade Visual , Vitrectomia
20.
Phys Rev Lett ; 87(24): 246403, 2001 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-11736522

RESUMO

We report on the transfer of coherence from a quantum-well electron-hole condensate to the light it emits. As a function of density, the coherence of the electron-hole-pair system evolves from being full for the low-density Bose-Einstein condensate to a chaotic behavior for a high-density BCS-like state. This degree of coherence is transferred to the light emitted in a damped oscillatory way in the ultrafast regime. Additionally, the photon field exhibits squeezing properties during the transfer time. Our results suggest a new type of ultrafast experiments for detecting electron-hole-pair condensation.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA