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1.
Neurol Sci ; 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39066836

RESUMEN

BACKGROUND: Caregivers' involvement in the diagnostic and monitoring processes of the level of consciousness of patients with Disorders of Consciousness (DoC) is strongly encouraged by international guidelines, as current literature suggests a better chance to detect behavioural responses when caregivers are involved in clinical assessments. Since caregivers' involvement during clinical assessments can be difficult, the Social And Family Evaluation (SAFE) scale has been recently proposed as a standardised tool that caregivers can autonomously use to collect their opinions about the level of consciousness of patients with DoC, based on the behaviours manifested by the patients in a given time-window. OBJECTIVE: Providing preliminary results concerning SAFE adoption. METHODS: 22 patients with DoC were assessed through the Coma Recovery Scale-revised (CRS-r), while their caregivers filled-in the SAFE. RESULTS: The SAFE showed a very high internal consistency, very high test-retest reliability, and high criterion validity when correlated to the CRS-r total score. Moreover, in line with the literature, the SAFE allowed the detection of some behaviours indicative of a higher level of consciousness than those detected by clinicians through the CRS-r in more than half of the sample. CONCLUSION: Overall, these preliminary data are promising for the adoption of the SAFE to collect the opinions of the caregivers about the level of consciousness of patients with DoC, especially in those settings where it would be otherwise difficult to monitor the patients, such as long-term care structures and at home, as a tool for telemedicine allowing the monitoring of patients in remote settings.

2.
Crit Care ; 26(1): 245, 2022 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-35948933

RESUMEN

The use of instrumental tools for improving both the diagnostic accuracy and the prognostic soundness in patients with disorders of consciousness (DOC) plays an important role. However, the most recent international guidelines on DOC published by the American and the European Academies of Neurology and by the UK Royal College of Physicians contain heterogeneous recommendations on the implementation of these techniques in the clinical routine for both diagnosis and prognosis. With the present work, starting from the comparison of the DOC guidelines' recommendations, we look for possible explanations behind such discrepancies considering the adopted methodologies and the reference health systems that could have affected the guidelines' perspectives. We made a provocative argument about the need to find the most appropriate common methodology to retrieve and grade the evidence, increase the meta-analytic studies, and reduce the health policies that influence on the guidelines development that, in turn, should inform the health policies with the strongest scientific evidence.


Asunto(s)
Estado de Conciencia , Neurología , Trastornos de la Conciencia/diagnóstico , Humanos , Pronóstico , Reino Unido , Estados Unidos
3.
J Phys Chem A ; 121(27): 5088-5099, 2017 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-28598167

RESUMEN

We report in this paper an investigation on energy transfer processes from vibration to vibration and/or translation in thermal and subthermal regimes for the O2 + N2 system performed using quantum-classical calculations on different empirical, semiempirical, and ab initio potential energy surfaces. In particular, the paper focuses on the rationalization of the non-Arrhenius behavior (inversion of the temperature dependence) of the quasi-resonant vibration-to-vibration energy transfer transition rate coefficients at threshold. To better understand the microscopic nature of the involved processes, we pushed the calculations to the detail of the related cross sections and analyzed the impact of the medium and long-range components of the interaction on them. Furthermore, the variation with temperature of the dependence of the quasi-resonant rate coefficient on the vibrational energy gap between initial and final vibrational states and the effectiveness of quantum-classical calculations to overcome the limitations of the purely classical treatments were also investigated. These treatments, handled in an open molecular science fashion by chaining data and competencies of the various laboratories using a grid empowered molecular simulator, have allowed a rationalization of the dependence of the computed rate coefficients in terms of the distortion of the O2-N2 configuration during the diatom-diatom collisions. A way of relating such distortions to a smooth and continuous progress variable, allowing a proper evolution from both long to closer range formulation of the interaction and from its entrance to exit channel (through the strong interaction region) relaxed graphical representations, is also discussed in the paper.

4.
J Phys Chem A ; 120(27): 5208-19, 2016 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-26982814

RESUMEN

Prompted by a comparison of measured and computed rate coefficients of Vibration-to-Vibration and Vibration-to-Translation energy transfer in O2 + N2 non-reactive collisions, extended semiclassical calculations of the related cross sections were performed to rationalize the role played by attractive and repulsive components of the interaction on two different potential energy surfaces. By exploiting the distributed concurrent scheme of the Grid Empowered Molecular Simulator we extended the computational work to quasiclassical techniques, investigated in this way more in detail the underlying microscopic mechanisms, singled out the interaction components facilitating the energy transfer, improved the formulation of the potential, and performed additional calculations that confirmed the effectiveness of the improvement introduced.

5.
J Phys Chem B ; 120(8): 1476-85, 2016 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-26292835

RESUMEN

By following the scheme of the Grid Empowered Molecular Simulator (GEMS), a new O2 + N2 intermolecular potential, built on ab initio calculations and experimental (scattering and second virial coefficient) data, has been coupled with an appropriate intramolecular one. On the resulting potential energy surface detailed rate coefficients for collision induced vibrational energy exchanges have been computed using a semiclassical method. A cross comparison of the computed rate coefficients with the outcomes of previous semiclassical calculations and kinetic experiments has provided a foundation for characterizing the main features of the vibrational energy transfer processes of the title system as well as a critical reading of the trajectory outcomes and kinetic data. On the implemented procedures massive trajectory runs for the proper interval of initial conditions have singled out structures of the vibrational distributions useful to formulate scaling relationships for complex molecular simulations.

6.
Phys Chem Chem Phys ; 13(16): 7475-84, 2011 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-21431105

RESUMEN

The Eley-Rideal recombination reaction of H chemisorbed on the four-fold site of W(001) at a surface temperature T(S) = 500 K is studied using the fully three-dimensional semiclassical collisional model and an accurate potential energy surface for the H-W(001) system. The recombination probability, calculated at different collisional energies in the range (0.05-5) eV, shows a broad maximum around 0.4 for energies between 0.1 eV and 2.5 eV. The exothermic energy partitioning in the final states of the desorbing H(2) molecules shows that, at low impact energies, only the first three vibrational levels of the hydrogen molecule are energetically accessible, while at the higher impact energies vibrational levels up to v = 7 can be populated. The energy exchanged with the phonons surface is small but not negligible.

7.
J Phys Chem A ; 113(52): 15366-75, 2009 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-19845325

RESUMEN

The adsorption dynamics of atomic oxygen on a model beta-cristobalite silica surface has been studied by combining ab initio electronic structure calculations with a molecular dynamics semiclassical approach. We have evaluated the interaction potential of atomic and molecular oxygen interacting with an active Si site of a model beta-cristobalite surface by performing DFT electronic structure calculations. As expected, O is strongly chemisorbed, E(b) = 5.57 eV, whereas molecular oxygen can be weakly adsorbed with a high-energy barrier to the adsorption state of approximately 2 eV. The binding energies calculated for silica clusters of different sizes have revealed the local nature of the O,O(2)-silica interaction. Semiclassical collision dynamic calculations show that O is mainly adsorbed in single-bounce collisions, with a smaller probability for adsorption via a multicollision mechanism. The probability for adsorption/desorption (reflected) collisions at the three impact energies is small but not negligible at the higher energy considered in the trajectory calculations, about P(r) = 0.2 at E(kin) = 0.8 eV. The calculations give evidence of a complex multiphonon excitation-deexcitation mechanism underlying the dynamics of stable adsorption and inelastic reflection collisions.

10.
Chemphyschem ; 9(1): 171-81, 2008 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-18098253

RESUMEN

We highlight the isotope and surface temperature effects for hydrogen atom recombination on a graphite surface. The reaction dynamics is studied using the semiclassical collisional method, according to which the mass and temperature effects are due to the coupling between the H/D dynamics and the dynamics of the phonon excitation/de-excitation mechanism of the substrate. All possible collisional schemes with H/D adsorbed on the surface and H/D impinging from the gas phase are considered. In particular, we focus on the recombination reaction between an H atom colliding with a D atom adsorbed on the surface and a D atom incident on an H adatom. For H(2) and D(2) formation, the surface temperature effect is investigated by comparing the results obtained for T(S)=800 K with those obtained at T(S)=500 K and T(S)=100 K. Despite the low masses involved in the dynamics, effective isotope and temperature effects were observed on the recombination probabilities, reaction energetics, and roto-vibrational states of formed molecules. The results show the need for correct treatment of the multiphonon excitation mechanism in molecule-surface interactions.


Asunto(s)
Química Física/métodos , Grafito , Hidrógeno/química , Algoritmos , Catálisis , Gases , Enlace de Hidrógeno , Modelos Estadísticos , Modelos Teóricos , Protones , Propiedades de Superficie , Temperatura , Termodinámica
11.
J Phys Chem A ; 111(30): 7057-65, 2007 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-17628049

RESUMEN

The state-to-state collisional data on vibration-vibration and vibration-translation/rotation energy exchanged in N2(v)-N2(v') collisions recently obtained from accurate ab initio semiclassical calculations have been used to analyze the data measured in nitrogen under two different plasma conditions. In particular, the vibrational distribution function and the time-evolution of the gas temperature measured under post-discharge and glow discharge conditions, respectively, have been calculated and compared with the experimental observations. The theoretical analysis and the related results, generally in very good agreement with the experimental data, provide insight into the various energy-exchange mechanisms that lie behind the macroscopic behaviors of the nitrogen plasmas. In particular, the role played by the vibrationally excited nitrogen molecules in the gas kinetics is pointed out, as well as the importance of nitrogen atom production in the long time scales of the glow discharge.

12.
Langmuir ; 22(17): 7208-16, 2006 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-16893217

RESUMEN

A joint experimental and theoretical approach has been developed to study oxygen atom recombination on a beta-quartz surface. The experimental MESOX setup has been applied for the direct measurement of the atomic oxygen recombination coefficient gamma at T(S) = 1000 K. The time evolution of the relative atomic oxygen concentration in the cell is described by the diffusion equation because the mean free path of the atoms is less than the characteristic dimension of the reactor. The recombination coefficient gamma is then calculated from the concentration profile obtained by visible spectroscopy. We get an experimental value of gamma = 0.008, which is a factor of about 3 less than the gamma value reported for O recombination over beta-cristobalite. The experimental results are discussed and compared with the semiclassical collision dynamics calculations performed on the same catalytic system aimed at determining the basic features of the surface catalytic activity. Agreement, both qualitative and quantitative, between the experimental and the theoretical recombination coefficients has been found that supports the Eley-Rideal recombination mechanism and gives more evidence of the impact that surface crystallographic variation has on catalytic activity. Also, several interesting aspects concerning the energetics and the mechanism of the surface processes involving the oxygen atoms are pointed out and discussed.

13.
J Chem Phys ; 123(17): 174315, 2005 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-16375536

RESUMEN

The vibrational energy relaxation in collisions between N2 molecules in the low- and medium-lying vibrationally excited levels was revisited using the semiclassical coupled-state method and the use of two different potential-energy surfaces having the same short-range potential recently determined from ab initio calculations but with different long-range interactions. Compared to the data reported in the classical work by Billing and Fisher [Chem. Phys. 43, 395 (1979)], the newly calculated vibration-to-translation rate constant K(1,0 / 0,0) is in much better agreement with the available experimental data over a large temperature interval, from T = 200 K up to T = 6000 K. Nevertheless, as far as the vibration-to-translation exchanges are concerned, the lower-temperature regime remains quite critical in that the new rate constants do not completely account for the rate constant curvature suggested by the experiments for temperatures lower than T = 500 K. The dependence of the state-selected vibration-to-vibration rate constants, K(v,v-delta v / 0,1), both upon the vibrational quantum number v and the gas temperature are calculated. The substantial deviations from previously found behaviors could have major consequences for the vibrational kinetic modeling of N2-containing gas mixtures.

14.
Am J Med Sci ; 307(2): 112-4, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8141136

RESUMEN

Castleman disease, or angiofollicular lymph node hyperplasia, and POEMS (Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal gammopathy, and Skin changes), are associated and can lead to a clinical conundrum. The physician caring for a patient with Castleman disease should be alert to the development of multiple endocrine deficiencies, including primary hypogonadism, diabetes mellitus, hypothyroidism, and adrenal insufficiency. Avoidance of treating hypothyroidism alone when there is concomitant subclinical adrenal insufficiency is important, to avoid precipitating an adrenal crisis. A better outcome may result from earlier recognition of the endocrinopathies of this syndrome. This article describes a patient with Castleman disease in whom the features of POEMS unfolded over the ensuing years.


Asunto(s)
Enfermedad de Castleman/complicaciones , Síndrome POEMS/complicaciones , Corticoesteroides , Hormona Adrenocorticotrópica , Enfermedad de Castleman/diagnóstico , Enfermedad de Castleman/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Hidrocortisona/sangre , Hipotiroidismo/diagnóstico , Hipotiroidismo/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Síndrome POEMS/diagnóstico , Pruebas de Función de la Tiroides , Tirotropina/sangre , Tiroxina/uso terapéutico , Tomografía Computarizada por Rayos X
17.
Urol Int ; 46(2): 159-62, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-2053224

RESUMEN

Both PC-3 and DU-145 cell lines are androgen-insensitive, but, in our experience, they contain androgen receptors (AR). Treatment of these cells with natural beta-interferon at a concentration of 1,000 IU/ml of culture medium determines an increase of AR (evaluated by a whole-cell assay), statistically significant with respect to control. Androgen unresponsiveness of our cells could be due to an AR level which is lower than that present in hormone-sensitive prostatic cancer cell lines, such as LNCaP cells. For this reason, interferon-promoted AR increase merits further investigation, even if other defects in receptor mechanism, responsible for hormone insensitivity, cannot be excluded.


Asunto(s)
Interferón Tipo I/farmacología , Neoplasias de la Próstata/metabolismo , Receptores Androgénicos/metabolismo , Línea Celular , Humanos , Masculino , Células Tumorales Cultivadas/metabolismo
18.
Ann N Y Acad Sci ; 595: 328-33, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2375611

RESUMEN

Our preliminary experience shows that flutamide is effective in patients with stage C or D prostate cancer. Local and distant response rates are comparable to those obtained with "classic" hormone therapy. Libido and sexual potency generally are unaffected. Palliation of symptoms, which is frequent, is usually accompanied by improved performance status and quality of life. Side effects are slight or moderate, but elevated transaminase levels in patients with borderline liver insufficiency are possible.


Asunto(s)
Antagonistas de Andrógenos/uso terapéutico , Carcinoma/tratamiento farmacológico , Imidazolidinas , Neoplasias de la Próstata/tratamiento farmacológico , Antagonistas de Andrógenos/efectos adversos , Flutamida/uso terapéutico , Humanos , Imidazoles/uso terapéutico , Masculino
19.
Prog Clin Biol Res ; 350: 149-57, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2201041

RESUMEN

Our preliminary experience shows that flutamide is an effective treatment in patients with stage C and D prostate cancer. Local and distant response rates appear to be comparable with those obtained by "classic" hormone therapy. Libido and sexual potency are generally not affected. Palliation of symptoms is frequent and is usually accompanied by improvement of performance status and quality of life. The side effects are slight or moderate, but an elevation of transaminases in patients with borderline liver insufficiency is possible.


Asunto(s)
Anilidas/uso terapéutico , Flutamida/uso terapéutico , Imidazoles/uso terapéutico , Imidazolidinas , Neoplasias Hormono-Dependientes/tratamiento farmacológico , Neoplasias de la Próstata/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Terapia Combinada , Dietilestilbestrol/efectos adversos , Dietilestilbestrol/uso terapéutico , Evaluación de Medicamentos , Disfunción Eréctil/inducido químicamente , Disfunción Eréctil/prevención & control , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Humanos , Imidazoles/administración & dosificación , Italia , Libido/efectos de los fármacos , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Neoplasias Hormono-Dependientes/sangre , Neoplasias Hormono-Dependientes/cirugía , Orquiectomía , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/cirugía , Calidad de Vida , Testosterona/sangre
20.
Pathologica ; 81(1072): 109-26, 1989.
Artículo en Italiano | MEDLINE | ID: mdl-2475847

RESUMEN

A series of 72 cases of prostatic carcinoma, together with another of 20 cases of benign prostatic hyperplasia, serum PSA levels of which were available, are investigated, concerning their immunohistochemical responsiveness both to PSA and PAP. Particularly, parameters of 54 cases are statistically correlated, a significant correlation standing out between tumoral "grading" and PSA and PAP immunohistochemical patterns. Moreover, the two markers used show some useful complementary features. Concerning the serum PSA levels, they correlate more significantly with "staging" than with "grading" of the tumors. Then, the biological characterization of prostatic carcinomas, at least in the Authors' experience, should be improved any further if both the serum PSA levels and the PSA and/or PAP immunohistochemical patterns of tumors may be available together.


Asunto(s)
Adenocarcinoma/análisis , Antígenos de Neoplasias/análisis , Biomarcadores de Tumor/sangre , Neoplasias de la Próstata/análisis , Fosfatasa Ácida/análisis , Adenocarcinoma/inmunología , Adenocarcinoma/patología , Anciano , Humanos , Masculino , Antígeno Prostático Específico , Hiperplasia Prostática/inmunología , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/patología
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