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1.
Clin Oral Investig ; 22(9): 3061-3070, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29476334

RESUMO

OBJECTIVES: The aim of this case-control study was to carry out an oral health assessment on a group of Alzheimer's patients and to establish a hypothesis regarding the implication of the characteristics of the disease and the treatment of oral health. MATERIALS AND METHODS: A total of 70 Alzheimer's patients, residents at the Alzheimer Center Reina Sofia Foundation (Madrid, Spain) and at the Alzheimer State Reference Center (Salamanca, Spain), and 36 controls (companions/acquaintances), were studied by oral examination and saliva sampling. The oral health indices DMFT/DMFS, CPI, the prosthetic condition, oral hygiene, saliva volume, and pH, as well as the specific microbiological parameters governing the risk of developing caries were assessed. RESULTS: Alzheimer's patients exhibited, as compared to the control group, (1) fewer teeth (10.9 ± 10.5 vs 23.7 ± 6.5), (2) fewer obturations (2.2 ± 3.4 vs 6.6 ± 5.6), (3) fewer periodontally healthy sextants (0.1 ± 0.4 vs 1.4 ± 2.2), (4) worse oral hygiene (43.1 vs 72.2% brushed), (5) greater use of removable prostheses (47.8 vs 8.4%), (6) higher incidence of candida infection (11.8 vs 0.0%) and cheilitis (15.9 vs 0.0%), (7) lower salivary flow (0.6 ± 0.6 vs 1.1 ± 0.6), and (8) lower buffering capacity (46 vs 80%). CONCLUSIONS: After taking into account the influence of age, Alzheimer's patients had worse oral health (caries and periodontal disease), more mucosal lesions (cheilitis and candidiasis), and worse saliva quantity and quality. CLINICAL RELEVANCE: Clinicians should be aware of the implications of Alzheimer's disease in oral health, in order to stablish the effective preventive measures and the optimal treatment plan.


Assuntos
Doença de Alzheimer/complicações , Avaliação Geriátrica , Saúde Bucal , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espanha
2.
Phys Rev Lett ; 116(24): 249902, 2016 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-27367414

RESUMO

This corrects the article DOI: 10.1103/PhysRevLett.109.183601.

3.
Nature ; 457(7227): 291-5, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19148095

RESUMO

Semiconductor microcavities offer unique systems in which to investigate the physics of weakly interacting bosons. Their elementary excitations, polaritons-mixtures of excitons and photons-can accumulate in macroscopically degenerate states to form various types of condensate in a wide range of experimental configurations, under either incoherent or coherent excitation. Condensates of polaritons have been put forward as candidates for superfluidity, and the formation of vortices as well as elementary excitations with linear dispersion are actively sought as evidence to support this. Here, using a coherent excitation triggered by a short optical pulse, we have created and set in motion a macroscopically degenerate state of polaritons that can be made to collide with a variety of defects present in the microcavity. Our experiments show striking manifestations of a coherent light-matter packet, travelling at high speed (of the order of one per cent of the speed of light) and displaying collective dynamics consistent with superfluidity, although one of a highly unusual character as it involves an out-of-equilibrium dissipative system. Our main results are the observation of a linear polariton dispersion accompanied by diffusionless motion; flow without resistance when crossing an obstacle; suppression of Rayleigh scattering; and splitting into two fluids when the size of the obstacle is comparable to the size of the wave packet. This work opens the way to the investigation of new phenomenology of out-of-equilibrium condensates.

4.
Eur J Cancer Care (Engl) ; 24(5): 635-41, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24990487

RESUMO

Research findings about health-related quality of life (HRQoL) of childhood cancer survivors are mixed and the features which could modulate these results have not been investigated rigorously. This research aims to improve the knowledge on these topics. Thus, HRQoL between central nervous system (CNST) and non-central nervous system (non-CNST) adolescent cancer survivors was compared. The influence of selected factors (gender and years since diagnosis) on HRQoL was also analysed. In a cross-sectional design, 78 survivors (12-20 years) who were ≥ 1 year free of oncological treatment answered the self-reported version of the KIDSCREEN-52. HRQoL mean scores of CNST survivors were lower in comparison with non-CNST in physical well-being and social support and peers dimensions. Furthermore, female gender was also related to lower HRQoL scores for both types of tumours in physical well-being and autonomy dimensions. Additionally, scores on psychological well-being, social support and peers, parent relations and home life and school environment dimensions decrease with length of time from diagnosis. Therefore, diagnosis of CNST and gender were related to lower HRQoL among survivors in some dimensions, whereas time from diagnosis was related to impaired HRQoL in other features. These results can help to design tailored interventions and psychosocial guidelines to follow-up survivors.


Assuntos
Neoplasias/psicologia , Qualidade de Vida , Fatores Sexuais , Sobreviventes/psicologia , Adolescente , Adulto , Fatores Etários , Neoplasias do Sistema Nervoso Central/psicologia , Criança , Estudos Transversais , Feminino , Nível de Saúde , Humanos , Masculino , Qualidade de Vida/psicologia , Fatores de Tempo , Adulto Jovem
5.
Phys Rev Lett ; 110(12): 126801, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-25166831

RESUMO

Here we present the theoretical foundation of the strong coupling phenomenon between quantum emitters and propagating surface plasmons observed in two-dimensional metal surfaces. For that purpose, we develop a quantum framework that accounts for the coherent coupling between emitters and surface plasmons and incorporates the presence of dissipation and dephasing. Our formalism is able to reveal the key physical mechanisms that explain the reported phenomenology and also determine the physical parameters that optimize the strong coupling. A discussion regarding the classical or quantum nature of this phenomenon is also presented.

6.
Phys Rev Lett ; 109(18): 183601, 2012 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-23215277

RESUMO

A theory of correlations between N photons of given frequencies and detected at given time delays is presented. These correlation functions are usually too cumbersome to be computed explicitly. We show that they are obtained exactly through intensity correlations between two-level sensors in the limit of their vanishing coupling to the system. This allows the computation of correlation functions hitherto unreachable. The uncertainties in time and frequency of the detection, which are necessary variables to describe the system, are intrinsic to the theory. We illustrate the power of our formalism with the example of the Jaynes-Cummings model, by showing how higher order photon correlations can bring new insights into the dynamics of open quantum systems.

7.
Phys Rev Lett ; 108(6): 065301, 2012 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-22401081

RESUMO

We study the properties of a binary microcavity polariton superfluid coherently injected by two lasers at different momenta and energies. The crossover from the supersonic to the subsonic regime, where motion is frictionless, is described by evaluating the linear response of the system to a weak defect potential. We show that the coupling between the two components requires that either both components flow without friction or both scatter against the defect, though scattering can be small when the two fluids are weakly coupled. By analyzing the drag force exerted on a defect, we give a recipe to experimentally address the crossover from the supersonic to the subsonic regime.

8.
Phys Rev Lett ; 109(26): 266407, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23368594

RESUMO

We investigate the cross interactions in a two-component polariton quantum fluid coherently driven by two independent pumping lasers tuned at different energies and momenta. We show that both the hysteresis cycles and the on-off threshold of one polariton signal can be entirely controlled by a second polariton fluid. Furthermore, we study the ultrafast switching dynamics of a driven polariton state, demonstrating the ability to control the polariton population with an external laser pulse, in less than a few picoseconds.

9.
Phys Rev Lett ; 106(2): 020501, 2011 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-21405211

RESUMO

We investigate qubit-qubit entanglement mediated by plasmons supported by one-dimensional waveguides. We explore both the situation of spontaneous formation of entanglement from an unentangled state and the emergence of driven steady-state entanglement under continuous pumping. In both cases, we show that large values for the concurrence are attainable for qubit-qubit distances larger than the operating wavelength by using plasmonic waveguides that are currently available.

10.
Phys Rev Lett ; 107(3): 036401, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21838381

RESUMO

We study, both theoretically and experimentally, the occurrence of topological defects in polariton superfluids in the optical parametric oscillator (OPO) regime. We explain in terms of local supercurrents the deterministic behavior of both the onset and dynamics of vortex-antivortex pairs generated by perturbing the system with a pulsed probe. Using a generalized Gross-Pitaevskii equation, including photonic disorder, pumping and decay, we elucidate the reason why topological defects form in couples and can be detected by direct visualizations in multishot OPO experiments.

11.
Opt Express ; 18(7): 7002-9, 2010 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-20389720

RESUMO

We study the effect of pure dephasing on a two-level system in strong coupling in the nonlinear regime with the single mode of a cavity. The photoluminescence spectrum of the cavity has a robust tendency to display triplet structures, instead of the expected Jaynes-Cummings pairs of doublets at the incommensurate frequencies +/- (square root n +/- square root (n-1)) for integer n. We discuss recent experimental works that may already manifest signatures of single photon nonlinearities.

12.
Opt Express ; 18(12): 13301-8, 2010 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-20588459

RESUMO

We study the optical emission of single semiconductor quantum dots weakly coupled to a photonic-crystal micro-cavity. The linearly polarized emission of a selected quantum dot changes continuously its polarization angle, from nearly perpendicular to the cavity mode polarization at large detuning, to parallel at zero detuning, and reversing sign for negative detuning. The linear polarization rotation is qualitatively interpreted in terms of the detuning dependent mixing of the quantum dot and cavity states. The present result is relevant to achieve continuous control of the linear polarization in single photon emitters.

13.
Phys Rev Lett ; 105(6): 063902, 2010 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-20867980

RESUMO

We study nonequilibrium polariton superfluids in the optical-parametric-oscillator regime by using a Gross-Pitaevskii equation with pumping and decay. We identify a regime above the optical-parametric-oscillator threshold, where the system undergoes spontaneous symmetry breaking and is unstable towards vortex formation without any rotating drive. Stable vortex solutions differ from metastable ones; the latter can persist but can be triggered only externally. Both spontaneous and triggered vortices are characterized by a generalized healing length, specified by the optical-parametric-oscillator parameters only.

14.
Nanotechnology ; 21(13): 134025, 2010 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-20208103

RESUMO

We present several examples of the interesting phenomenology shown by a moving polariton condensate in semiconductor microcavities. The superfluid behavior is probed by colliding the polariton condensate against physical obstacles in the form of natural defects of the sample, demonstrating a clear suppression of scattering when the speed of the flow lies below the critical velocity. At higher velocities Cerenkov-like shock waves around the defect and disruption of the condensate are also observed.

15.
Rehabilitacion (Madr) ; 53(1): 20-27, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-30929829

RESUMO

INTRODUCTION AND OBJECTIVES: Autonomic nervous system (ANS) dysfunction in patients with spinal cord injury (SCI) severely impacts morbidity and mortality. However, research initiatives aiming to gain insight into the direct impact of ANS dysfunction on health outcomes in persons with SCI are still lacking. Thus, this study had 2main objectives: 1) to translate into Spanish the revised edition of the International Standards on documentation of remaining Autonomic Function after SCI (ISAFSCI), and 2) to describe the impact of ANS dysfunction in a sample of SCI patients. MATERIAL AND METHODS: Cross-sectional observational pilot study in 51 traumatic SCI patients (> 1 year after injury). Demographic, medical and ISAFSCI data were studied. RESULTS: The Spanish version of the ISAFSCI showed that the most altered systems in the sample were sweating control (above-lesion hyperhidrosis in 33.3%; below-lesion hyperhidrosis in 17.6%; below-lesion hypohidrosis in 21.6%) and temperature control (hyperthermia in 76.5%). In addition, 74.5% of the sample had complete loss of control of the lower urinary tract, and 82.4% had no control of the bowel. Finally, genital arousal was reflex in 47.1% and orgasm and ejaculation were reduced or altered in most of the patients (92.2% and 84.3%, respectively). CONCLUSION: The Spanish version of the ISAFSCI is a useful and practical tool, and can be employed in clinical practice to assess ANS function in patients with SCI. Understanding the role of ANS in persons with SCI is crucial to improve their health status and reduce secondary complications post-SCI, and consequently help to improve the clinical management in these individuals.


Assuntos
Doenças do Sistema Nervoso Autônomo/diagnóstico , Sistema Nervoso Autônomo/fisiopatologia , Traumatismos da Medula Espinal/complicações , Adolescente , Adulto , Idoso , Doenças do Sistema Nervoso Autônomo/etiologia , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Estudos Transversais , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Adulto Jovem
16.
Rehabil Res Pract ; 2016: 8109365, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27195152

RESUMO

Objectives. (1) To describe the epidemiological and medical features of a sample with LLA and LLD in childhood and (2) to explore their relationship with subsequent physical and psychosocial functions in adulthood. Methods. Cross-sectional survey. Demographics, medical data, Locomotor Capabilities Index (LCI), and Discomfort-Engagement in Everyday Activities Involving Revealing the Body Scale (D-EEARB) were collected from thirty-two adults who suffered from LLA in childhood or LLD. Results. Most of the sample (53.1% males) was working (84.4%), living independently (75%), and single (75%). Mean age was 33.16 (SD = 7.64, range 18-50). Leading causes for LLA were traumatic (40.6%) and oncologic (25%). LLD was present in 6 cases (18.8%). LCI scores revealed a high performance among males (t 17,464 = 2.976, p = .008). D-EEARB scores showed that 56.25% stated feeling "quite" or "totally comfortable" in situations which involved revealing their body, but 43.75% stated the contrary ("uncomfortable" or "very uncomfortable"). LLD and traumatic LLA show higher scores in D-EEARB than vascular and oncological LLA (χ (2) = 7.744, df = 3, p = .05). Conclusions. Adults suffering from LLDs and LLAs during childhood seem to perform well once they are adults. However, 43.75% of patients express considerable discomfort in situations that involve revealing the body.

17.
Intensive Care Med ; 26(11): 1670-80, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11193275

RESUMO

OBJECTIVE: To define the acute hemodynamic, metabolic, and morphological changes induced by aminoguanidine, a selective iNOS inhibitor, in septic sheep. DESIGN: Prospective, nonrandomized animal study. SETTING: Animal research facility in a University Hospital. INTERVENTIONS: Adult sheep, sedated and mechanically ventilated, were monitored with a pulmonary arterial catheter and an ultrasonic blood flow probe in the mesenteric artery, to measure the systemic (Q(TOT)I) and the mesenteric (Q(MES)I) blood flow indices, and an ileal tonometer. Four groups of sheep were studied: nonseptic, septic, nonseptic treated with aminoguanidine, and septic treated with aminoguanidine (100 mg kg(-1) h(-1)) (n = 6 for each group). Sepsis was induced by the intravenous administration of E. coli. Hemodynamic and biochemical parameters were measured during 300 min. Histological changes in the liver and small intestinal mucosa were analyzed at the end of the experiment. MEASUREMENTS AND MAIN RESULTS: In nonseptic animals, aminoguanidine slightly increased mean systemic arterial pressure (MAP), decreased Q(TOT)I, and increased vascular resistance index (SVRI) and pulmonary vascular resistance index. Q(MEs)I did not change and Q(MES)I/Q(ToT)I increased. Aminoguanidine also induced intestinal intramucosal hypercarbia, hyperlactatemia, acidemia, hypoglycemia, and morphological signs indicative of tissue ischemia in the small intestinal mucosa. In septic sheep, aminoguanidine increased SVRI and MAP only at 4 h after the septic challenge and thereafter, and worsened gas exchange. CONCLUSIONS: In this model, exogenous administration of aminoguanidine induces beneficial hemodynamic effects 4 h after the septic challenge. In normal animals, however, aminoguanidine was associated with hypoglycemia, acidosis, hyperlactatemia, and intestinal mucosal ischemia.


Assuntos
Inibidores Enzimáticos/farmacologia , Guanidinas/farmacologia , Hemodinâmica/efeitos dos fármacos , Óxido Nítrico Sintase/antagonistas & inibidores , Sepse/tratamento farmacológico , Acidose/induzido quimicamente , Análise de Variância , Animais , Pressão Sanguínea/efeitos dos fármacos , Estudos de Casos e Controles , Inibidores Enzimáticos/uso terapêutico , Guanidinas/uso terapêutico , Hipoglicemia/induzido quimicamente , Mucosa Intestinal/irrigação sanguínea , Mucosa Intestinal/efeitos dos fármacos , Isquemia/induzido quimicamente , Lactose/sangue , Insuficiência de Múltiplos Órgãos/prevenção & controle , Estudos Prospectivos , Ovinos , Fatores de Tempo , Resistência Vascular/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos
18.
J Virol Methods ; 72(2): 227-35, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9694330

RESUMO

A RT-PCR assay based on specific amplification of RNA sequences from each of the etiological agents of three important vesicular diseases that affect swine, foot-and-mouth disease virus (FMDV), swine vesicular disease virus (SVDV), and vesicular stomatitis virus (VSV), was developed. Genotype-specific primers that amplified DNA fragments of differential size from SVDV 3D gene or VSV L gene were selected with the aid of a computer program. Experimental testing of the primers predicted as SVDV-specific identified a primer pair, SA2/SS4, that rendered a specific product from SVDV RNAs, but did not amplify RNA from either FMDV or coxsackie B5 virus (CV-B5), a highly related picornavirus. Primers SA2/SS4 were used in combination with primers 3D2/3D1, which amplify a product of different size on FMDV 3D gene (Rodriguez et al., 1992). This combined RT-PCR reaction allowed a sensitive and specific differential detection of FMDV and SVDV RNAs in a single tube, by means of the analysis of the amplified products in agarose gels. The results obtained were similar when RNA extracted from viral stocks or plastic wells coated with either viral supernatants or extracts from lesions of infected animals, were used as starting material in the reactions. Using a similar approach, VSV serotype-specific primers IA/IS and NA/NS were selected for the specific amplification of VSV-Indiana and VSV-New Jersey RNAs, respectively. The combined use of SVDV, FMDV and VSV specific primers in a single reaction resulted in a genotype-specific amplification of each of the viral RNAs. Thus, differential diagnosis of FMDV from SVDV and/or VSV can be carried out in a single RT-PCR reaction, using a rapid and simplified methodology.


Assuntos
Febre Aftosa/diagnóstico , Reação em Cadeia da Polimerase/veterinária , Infecções por Rhabdoviridae/veterinária , Estomatite/veterinária , Doenças dos Suínos/diagnóstico , Doença Vesicular Suína/diagnóstico , Vírus da Estomatite Vesicular Indiana , Animais , Aphthovirus/isolamento & purificação , Primers do DNA , Diagnóstico Diferencial , Eletroforese em Gel de Ágar , Amplificação de Genes , Genes Virais/genética , Genótipo , Reação em Cadeia da Polimerase/métodos , RNA Viral/genética , Infecções por Rhabdoviridae/diagnóstico , Alinhamento de Sequência , Estomatite/diagnóstico , Suínos , Doenças dos Suínos/virologia , Vírus da Estomatite Vesicular Indiana/isolamento & purificação
19.
Eur J Histochem ; 37(1): 75-82, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7682871

RESUMO

The experiments were designed to analyse the efficiency of the Indirect Fluorescent Antibody Test (IFAT), the Avidin-Biotin-Peroxidase Complex (ABPC) and Transmission Electron Microscopy (TEM) in detecting Bovine Respiratory Syncytial Virus (BRSV) antigen in ovine lung. 25 gnotobiotic Merino lambs each received an intratracheal injection of 20 ml of BRSV infected cell culture suspension (strain NMK-7) diluted at the concentration of 1.26 x 10(6) TCID50/ml. Results showed that the immunological techniques were more efficient than transmission electron microscopy in detecting BRSV antigen. IFAT and ABPC yielded identical results. However, difficulties in interpreting aspecific fluorescence, coupled with the ease of identification of pneumonic areas from paraffin-embedded tissues, suggest that ABPC is the most suitable technique for identifying BRSV antigen in the lungs of experimentally-infected sheep.


Assuntos
Antígenos Virais/análise , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções por Respirovirus/veterinária , Doenças dos Ovinos/microbiologia , Animais , Imunofluorescência/veterinária , Técnicas Imunoenzimáticas/veterinária , Microscopia Eletrônica/veterinária , Vírus Sinciciais Respiratórios/imunologia , Infecções por Respirovirus/microbiologia , Ovinos
20.
Rev Sci Tech ; 17(3): 660-73, 1998 Dec.
Artigo em Francês | MEDLINE | ID: mdl-9850537

RESUMO

African swine fever was reported for the first time in the Côte d'Ivoire on 16 April 1996, in Abidjan. The epizootic resulted in the death of 135,000 pigs, equivalent to 29% of the pig population, of which 80% came from the commercial sector. By November, the outbreaks had stabilised and were then eliminated. All epidemiological evidence showed that the active form of disease ceased in September 1996. A variety of factors were responsible for limiting and then halting progression of the disease from the end of August 1996, including a new strategy which gave priority to local information, better control of the situation, depopulation of the infected area in Abidjan, the epidemiological containment of most cases within the villages, and also the assistance and direct involvement of the Food and Agriculture Organization (FAO) of the United Nations. The contribution of the FAO was decisive. It provided a diagnosis of the situation, recommended emergency measures, developed a control strategy, ensured the implementation of the control programme, set up a diagnostic laboratory unit and provided training for staff, slaughtered and destroyed any remaining pigs, set up and implemented a local information programme, developed and implemented a scheme for sentinel animals and for epidemiological surveillance, and designed, performed and analysed an epidemiological survey. From the commencement of the epizootic, two major shortcomings became apparent: inadequate dissemination of information, and a shortage of technical resources allocated for the control of African swine fever. These two shortcomings were compounded by other technical and socio-economic constraints.


Assuntos
Febre Suína Africana/epidemiologia , Surtos de Doenças/veterinária , Febre Suína Africana/diagnóstico , Febre Suína Africana/prevenção & controle , Animais , Côte d'Ivoire/epidemiologia , Surtos de Doenças/prevenção & controle , Suínos , Nações Unidas
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