Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 43
Filtrar
1.
Entropy (Basel) ; 26(5)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38785619

RESUMO

With this follow-up paper, we continue developing a mathematical framework based on information geometry for representing physical objects. The long-term goal is to lay down informational foundations for physics, especially quantum physics. We assume that we can now model information sources as univariate normal probability distributions N (µ, σ0), as before, but with a constant σ0 not necessarily equal to 1. Then, we also relaxed the independence condition when modeling m sources of information. Now, we model m sources with a multivariate normal probability distribution Nm(µ,Σ0) with a constant variance-covariance matrix Σ0 not necessarily diagonal, i.e., with covariance values different to 0, which leads to the concept of modes rather than sources. Invoking Schrödinger's equation, we can still break the information into m quantum harmonic oscillators, one for each mode, and with energy levels independent of the values of σ0, altogether leading to the concept of "intrinsic". Similarly, as in our previous work with the estimator's variance, we found that the expectation of the quadratic Mahalanobis distance to the sample mean equals the energy levels of the quantum harmonic oscillator, being the minimum quadratic Mahalanobis distance at the minimum energy level of the oscillator and reaching the "intrinsic" Cramér-Rao lower bound at the lowest energy level. Also, we demonstrate that the global probability density function of the collective mode of a set of m quantum harmonic oscillators at the lowest energy level still equals the posterior probability distribution calculated using Bayes' theorem from the sources of information for all data values, taking as a prior the Riemannian volume of the informative metric. While these new assumptions certainly add complexity to the mathematical framework, the results proven are invariant under transformations, leading to the concept of "intrinsic" information-theoretic models, which are essential for developing physics.

2.
Arch. Soc. Esp. Oftalmol ; 98(12): 723-726, dic. 2023.
Artigo em Espanhol | IBECS | ID: ibc-228148

RESUMO

La entrada en vigor del reglamento sobre productos sanitarios obliga a los clínicos a identificar y reportar a las autoridades sanitarias los posibles incidentes serios derivados de su utilización. Dadas las dudas que pueden suscitarse sobre qué puede o no considerarse incidente serio, un grupo de trabajo, creado por miembros de la Sociedad Española de Retina y Vitreo (SERV) y el clúster de oftalmología y ciencias de la visión (Cluster4Eye), han elaborado un documento que pretende orientar a los oftalmólogos sobre algunos de los incidentes que, en la experiencia del equipo de trabajo, no son habituales o pueden causar un serio daño a la función del paciente. (AU)


The entry into force of the regulation on medical devices obliges clinicians to identify and report to the Health Authorities possible serious incidents arising from their use. In view of the doubts that may arise as to whether or not it may be considered a serious incident, a working group, set up by members of the Spanish Society of Retina and Vitreous (SERV) and the cluster of ophthalmology and vision sciences (Cluster4Eye) have prepared a document that aims to guide ophthalmologists about some of the incidents that, in the experience of the work team, are not common or can cause serious damage to the patient's function. (AU)


Assuntos
Humanos , Procedimentos Cirúrgicos Oftalmológicos/efeitos adversos , Equipamentos e Provisões/normas , Consenso , Espanha
3.
Arch Soc Esp Oftalmol (Engl Ed) ; 98(12): 723-726, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37865190

RESUMO

The entry into force of the regulation on medical devices obliges clinicians to identify and report to the Health Authorities possible serious incidents arising from their use. In view of the doubts that may arise as to whether or not it may be considered a serious incident, a working group, set up by members of the Spanish Society of Retina and Vitreo and the cluster of ophthalmology and vision sciences (Cluster4Eye) have prepared a document that aims to guide ophthalmologists about some of the incidents that, in the experience of the work team, are not common or can cause serious damage to the patient's function.


Assuntos
Equipamentos e Provisões , Procedimentos Cirúrgicos Oftalmológicos , Oftalmologia , Humanos , Equipamentos e Provisões/efeitos adversos , Olho , Procedimentos Cirúrgicos Oftalmológicos/efeitos adversos , Regulamentação Governamental
4.
Entropy (Basel) ; 25(10)2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37895569

RESUMO

This work addresses J.A. Wheeler's critical idea that all things physical are information-theoretic in origin. In this paper, we introduce a novel mathematical framework based on information geometry, using the Fisher information metric as a particular Riemannian metric, defined in the parameter space of a smooth statistical manifold of normal probability distributions. Following this approach, we study the stationary states with the time-independent Schrödinger's equation to discover that the information could be represented and distributed over a set of quantum harmonic oscillators, one for each independent source of data, whose coordinate for each oscillator is a parameter of the smooth statistical manifold to estimate. We observe that the estimator's variance equals the energy levels of the quantum harmonic oscillator, proving that the estimator's variance is definitively quantized, being the minimum variance at the minimum energy level of the oscillator. Interestingly, we demonstrate that quantum harmonic oscillators reach the Cramér-Rao lower bound on the estimator's variance at the lowest energy level. In parallel, we find that the global probability density function of the collective mode of a set of quantum harmonic oscillators at the lowest energy level equals the posterior probability distribution calculated using Bayes' theorem from the sources of information for all data values, taking as a prior the Riemannian volume of the informative metric. Interestingly, the opposite is also true, as the prior is constant. Altogether, these results suggest that we can break the sources of information into little elements: quantum harmonic oscillators, with the square modulus of the collective mode at the lowest energy representing the most likely reality, supporting A. Zeilinger's recent statement that the world is not broken into physical but informational parts.

5.
Arch Soc Esp Oftalmol (Engl Ed) ; 96(11): 615-617, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34756286

RESUMO

We present the case of an 81-year-old woman who developed a bilateral spontaneous suprachoroidal hemorrhage while under treatment with sodium enoxaparin. Temporal suspension of anticoagulant therapy led to an improvement of the choroidal hemorrhage. After three months follow-up, there was a complete reabsorption of the choroidal detachments, but there was a persistent vitreous hemorrhage in the right eye, which had been more severely affected. Pars plana vitrectomy with air tamponade was successfully performed in the right eye. Vision improved to 20/50 in the right eye and 20/20 in the left eye. Suprachoroidal hemorrhage is a rare condition with a poor visual prognosis. Reports on the development of suprachoroidal hemorrhage in patients with no predisposing ocular conditions are scarce, and in none were both eyes affected. The case reported herein is, to the best of our knowledge, the first case of bilateral, simultaneous suprachoroidal hemorrhage without predisposing ocular factors due to treatment with anticoagulants, with a favourable visual outcome.


Assuntos
Hemorragia da Coroide , Idoso de 80 Anos ou mais , Hemorragia da Coroide/induzido quimicamente , Olho , Feminino , Heparina de Baixo Peso Molecular , Humanos , Acuidade Visual , Vitrectomia
6.
Arch Soc Esp Oftalmol (Engl Ed) ; 96 Suppl 1: 60-67, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34836590

RESUMO

This review updates the knowledge about the morphological assessment of the foveal hypoplasia in congenital aniridia and resumes the reported genotype-phenotype correlations known to date. Congenital aniridia is a pan ocular disease. Although iris absence is considered the hallmark of this entity, foveal hypoplasia is present in 94.7%-84% of patients. A foveal morphology assessed by optical coherence tomography in which external retina structures can be identified, with presence of the lengthening of photoreceptors outer segment and a greater external retinal thickness, is associated with a better visual outcome, regardless a foveal pit is identified or not. This analysis can be performed once the external retina has completed its differentiation, by 6 years old. PAX6 mutations that introduce premature termination codon, C terminal extension or PAX6 involving deletions have been related to lesser foveal differentiation. Better foveal differentiation has been associated to non-coding PAX6 mutations.


Assuntos
Aniridia , Aniridia/diagnóstico , Criança , Fóvea Central , Humanos , Iris , Fator de Transcrição PAX6/genética , Tomografia de Coerência Óptica
7.
Arch. Soc. Esp. Oftalmol ; 96(11): 615-617, nov. 2021. tab
Artigo em Espanhol | IBECS | ID: ibc-218289

RESUMO

Presentamos el caso de una paciente de 81 años en tratamiento con enoxaparina sódica, que desarrolló una hemorragia supracoroidea espontánea bilateral. Tras suspender el tratamiento anticoagulante se produjo una mejoría clínica, que se mantuvo incluso tras reiniciar la anticoagulación. Tras 3 meses de seguimiento, la hemorragia coroidea se resolvió completamente en ambos ojos, pero se decidió realizar una vitrectomía pars plana en el ojo derecho de la paciente, el más afectado inicialmente, debido a un hemovítreo persistente. La agudeza visual alcanzada fue de 20/50 en el ojo derecho y 20/20 en el ojo izquierdo. La hemorragia supracoroidea es una entidad poco frecuente, asociada habitualmente a un mal pronóstico visual. Se han descrito pocos casos en la literatura de hemorragia supracoroidea en pacientes sin factores de riesgo oculares, ninguno de ellos bilateral. Este podría ser el primer caso descrito en la literatura de hemorragia supracoroidea bilateral simultánea sin factores oculares predisponentes relacionado con anticoagulantes, resuelto con un buen resultado visual (AU)


We present the case of an 81-year-old woman who developed a bilateral spontaneous suprachoroidal hemorrhage while under treatment with sodium enoxaparin. Temporal suspension of anticoagulant therapy led to an improvement of the choroidal hemorrhage. After three months follow-up, there was a complete reabsorption of the choroidal detachments, but there was a persistent vitreous hemorrhage in the right eye, which had been more severely affected. Pars plana vitrectomy with air tamponade was successfully performed in the right eye. Vision improved to 20/50 in the right eye and 20/20 in the left eye. Suprachoroidal hemorrhage is a rare condition with a poor visual prognosis. Reports on the development of suprachoroidal hemorrhage in patients with no predisposing ocular conditions are scarce, and in none were both eyes affected. The case reported herein is, to the best of our knowledge, the first case of bilateral, simultaneous suprachoroidal hemorrhage without predisposing ocular factors due to treatment with anticoagulants, with a favourable visual outcome (AU)


Assuntos
Humanos , Feminino , Idoso de 80 Anos ou mais , Enoxaparina/efeitos adversos , Anticoagulantes/efeitos adversos , Hemorragia da Coroide/induzido quimicamente , Heparina de Baixo Peso Molecular/efeitos adversos , Vitrectomia
8.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33736873

RESUMO

This review updates the knowledge about the morphological assessment of the foveal hypoplasia in Congenital Aniridia and resumes the reported genotype-phenotype correlations known to date. Congenital Aniridia is a pan ocular disease. Although iris absence is considered the hallmark of this entity, foveal hypoplasia is present in 94.7-84% of patients. A foveal morphology assessed by optical coherence tomography in which external retina structures can be identified, with presence of the lengthening of photoreceptors outer segment and a greater external retinal thickness, is associated with a better visual outcome, regardless a foveal pit is identified or not. This analysis can be performed once the external retina has completed its differentiation, by 6 years old. PAX6 mutations that introduce premature termination codon, C terminal extension or PAX6 involving deletions have been related to lesser foveal differentiation. Better foveal differentiation has been associated to non-coding PAX6 mutations.

9.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33516565

RESUMO

We present the case of an 81-year-old woman who developed a bilateral spontaneous suprachoroidal hemorrhage while under treatment with sodium enoxaparin. Temporal suspension of anticoagulant therapy led to an improvement of the choroidal hemorrhage. After three months follow-up, there was a complete reabsorption of the choroidal detachments, but there was a persistent vitreous hemorrhage in the right eye, which had been more severely affected. Pars plana vitrectomy with air tamponade was successfully performed in the right eye. Vision improved to 20/50 in the right eye and 20/20 in the left eye. Suprachoroidal hemorrhage is a rare condition with a poor visual prognosis. Reports on the development of suprachoroidal hemorrhage in patients with no predisposing ocular conditions are scarce, and in none were both eyes affected. The case reported herein is, to the best of our knowledge, the first case of bilateral, simultaneous suprachoroidal hemorrhage without predisposing ocular factors due to treatment with anticoagulants, with a favourable visual outcome.

10.
Phys Rev Lett ; 119(20): 204801, 2017 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-29219328

RESUMO

A novel method to determine the total hydrogen density and, accordingly, a precise plasma temperature in a lowly ionized hydrogen plasma is described. The key to the method is to analyze the energy loss of swift heavy ions interacting with the respective bound and free electrons of the plasma. A slowly developing and lowly ionized hydrogen theta-pinch plasma is prepared. A Boltzmann plot of the hydrogen Balmer series and the Stark broadening of the H_{ß} line preliminarily defines the plasma with a free electron density of (1.9±0.1)×10^{16} cm^{-3} and a free electron temperature of 0.8-1.3 eV. The temperature uncertainty results in a wide hydrogen density, ranging from 2.3×10^{16} to 7.8×10^{18} cm^{-3}. A 108 MHz pulsed beam of ^{48}Ca^{10+} with a velocity of 3.652 MeV/u is used as a probe to measure the total energy loss of the beam ions. Subtracting the calculated energy loss due to free electrons, the energy loss due to bound electrons is obtained, which linearly depends on the bound electron density. The total hydrogen density is thus determined as (1.9±0.7)×10^{17} cm^{-3}, and the free electron temperature can be precisely derived as 1.01±0.04 eV. This method should prove useful in many studies, e.g., inertial confinement fusion or warm dense matter.

11.
Arch. Soc. Esp. Oftalmol ; 90(7): 331-334, jul. 2015.
Artigo em Espanhol | IBECS | ID: ibc-138254

RESUMO

CASO CLÍNICO: Varón de 46 años, acudió a Urgencias por disminución de agudeza visual y exoftalmos en ojo derecho. Aquejaba cefalea, diplopía de 4 meses de evolución e historia de desprendimiento neurosensorial (DNS) resuelto espontáneamente un mes antes. Presentaba tortuosidad de vasos conjuntivales y epiesclerales y nuevo DNS macular derecho. La sospecha de fístula carótido-cavernosa quedó confirmada mediante angiotomografía computarizada (angio-TC). Durante su ingreso la fístula se cerró espontáneamente. Al mes, el DNS había desaparecido. DISCUSIÓN: La fístula carótido-cavernosa debe incluirse en el diagnóstico diferencial de los DNS maculares. El DNS puede desaparecer espontáneamente al cerrarse la fístula


CASE REPORT: A 46 year-old man was seen in the emergency department complaining of vision loss and exophthalmos in his right eye. He also complained of headache, diplopia of 4 months onset, and neurosensory detachment that resolved spontaneously the month before. The study revealed tortuous conjunctival and episcleral vessels and neurosensory macular detachment in his right eye. A carotid-cavernous fistula was confirmed by computed tomography angiography. The fistula closed spontaneously during the hospitalization. One month later, the neurosensory detachment disappeared again. DISCUSSION: Carotid-cavernous fistula should be included in the differential diagnosis of neurosensory macular detachments. These neurosensory detachments can resolve spontaneously 11 the fistula is closed


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Descolamento Retiniano/complicações , Fístula Carótido-Cavernosa/complicações , Recidiva , Diagnóstico Diferencial
12.
Arch Soc Esp Oftalmol ; 90(7): 331-4, 2015 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-25443195

RESUMO

CASE REPORT: A 46 year-old man was seen in the emergency department complaining of vision loss and exophthalmos in his right eye. He also complained of headache, diplopia of 4 months onset, and neurosensory detachment that resolved spontaneously the month before. The study revealed tortuous conjunctival and episcleral vessels and neurosensory macular detachment in his right eye. A carotid-cavernous fistula was confirmed by computed tomography angiography. The fistula closed spontaneously during the hospitalization. One month later, the neurosensory detachment disappeared again. DISCUSSION: Carotid-cavernous fistula should be included in the differential diagnosis of neurosensory macular detachments. These neurosensory detachments can resolve spontaneously 11 the fistula is closed.


Assuntos
Fístula Carótido-Cavernosa/complicações , Macula Lutea , Descolamento Retiniano/etiologia , Transtornos da Visão/etiologia , Fístula Carótido-Cavernosa/diagnóstico , Fístula Carótido-Cavernosa/diagnóstico por imagem , Diagnóstico Diferencial , Emergências , Exoftalmia/etiologia , Angiofluoresceinografia , Humanos , Masculino , Pessoa de Meia-Idade , Petrosite/diagnóstico , Recidiva , Remissão Espontânea , Descolamento Retiniano/diagnóstico por imagem , Tomografia de Coerência Óptica , Tomografia Computadorizada por Raios X
14.
Arch. Soc. Esp. Oftalmol ; 88(11): 415-422, nov. 2013. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-129229

RESUMO

Objetivos: Determinar el efecto de la capsulotomía posterior en el grosor macular, presión intraocular (PIO) y pérdida de células endoteliales en pacientes pseudofáquicos que presentaban opacidad de la cápsula posterior, utilizando el ojo adelfo de cada paciente como control. Métodos: Se realizó un estudio prospectivo observacional en 31 pacientes pseudofáquicos con opacidad de la cápsula posterior en un ojo, utilizando el ojo adelfo como control durante un periodo de 3 meses. Se excluyó a los pacientes que presentaban otras enfermedades oculares o cirugías intraoculares aparte de la facoexéresis. A todos los pacientes se les realizó una capsulotomía posterior con láser Nd: YAG. El examen ocular, que se realizó previamente a la capsulotomía y en revisiones a la semana, al mes y a los 3 meses, incluía: agudeza visual mejor corregida (AVMC), PIO, tomografía de coherencia óptica macular (OCT) y recuento endotelial. Resultados: Se utilizaron ecuaciones de estimación generalizadas para valorar el efecto de la capsulotomía ajustado en función de situación basal y tiempo de seguimiento. No se encontró asociación significativa entre la capsulotomía y la PIO (p = 0,597), el grosor macular (p = 0,085) o el recuento endotelial (densitometría (p = 0,422), tamaño celular medio (p = 0,299), coeficiente de variación (p = 0,495), porcentaje de células hexagonales (0,093) y paquimetría (p = 0,423). Un incremento significativo de la AVMC se observó en la revisión a los 3 meses (p < 0,001). Conclusiones: Este estudio indica que, tras la capsulotomía posterior, la AVMC mejora significativamente, sin observarse cambios significativos en PIO, grosor macular o recuento endotelial. La capsulotomía con Nd:YAG es un procedimiento seguro en pacientes que no presenten enfermedades oculares asociadas (AU)


Objective: To determine the effect of posterior capsulotomy on macular thickness, intraocular pressure and endothelial cell loss in pseudophakic patients with posterior capsule opacification using the other eye of every patient as a control. Methods: An observational prospective study was conducted on 31 pseudophakic patients with posterior capsular opacification in one eye, using the other eye as a control. Patients did not suffer any other ocular pathology. All patients were treated by posterior capsular opacification with Nd: YAG capsulotomy, and followed up for a three-month period. The ocular examination included, best corrected visual acuity (BCVA), intraocular pressure (IOP),macular optical coherence tomography (OCT), and endothelial cell assessment (including densitometry, cell size and coefficient of variation, hexagonal cell percentage and pachymetry),which were determined in both eyes before treatment, and one week, one month and 3 months after capsulotomy. Results: Generalized estimating equations (GEE) were used to assess the capsulotomy effect adjusted by corresponding baseline measurements and time. No association was found between capsulotomy and IOP (P =0.597), macular thickness (P =0.085) or ECA (densitometry (P =0.422), average size of cells (P =0.299), variation coefficient (P =0.495), hexagonal cell percent (P =0.093) and corneal pachymetry (P =0.423). A significant increase of 0.15 Snellen units in BCVA was found during the 3-month follow-up period (P <0.001).Conclusion: This study shows that after Nd: YAG capsulotomy, BCVA improves significantly without any IOP, OCT or ECA changes during the three-month follow-up. Nd: YAG capsulotomy is a safe procedure in pseudophakic patients without any other ocular pathology (AU)


Assuntos
Humanos , Capsulorrexe/métodos , Cápsula Posterior do Cristalino/cirurgia , Pressão Intraocular , Pseudofacia/cirurgia , Estudos Prospectivos , Tomografia de Coerência Óptica , Acuidade Visual
15.
Arch Soc Esp Oftalmol ; 88(11): 415-22, 2013 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-24157319

RESUMO

OBJECTIVE: To determine the effect of posterior capsulotomy on macular thickness, intraocular pressure and endothelial cell loss in pseudophakic patients with posterior capsule opacification using the other eye of every patient as a control. METHODS: An observational prospective study was conducted on 31 pseudophakic patients with posterior capsular opacification in one eye, using the other eye as a control. Patients did not suffer any other ocular pathology. All patients were treated by posterior capsular opacification with Nd:YAG capsulotomy, and followed up for a three-month period. The ocular examination included, best corrected visual acuity (BCVA), intraocular pressure (IOP), macular optical coherence tomography (OCT), and endothelial cell assessment (including densitometry, cell size and coefficient of variation, hexagonal cell percentage and pachymetry), which were determined in both eyes before treatment, and one week, one month and 3 months after capsulotomy. RESULTS: Generalized estimating equations (GEE) were used to assess the capsulotomy effect adjusted by corresponding baseline measurements and time. No association was found between capsulotomy and IOP (P=.597), macular thickness (P=.085) or ECA (densitometry (P=.422), average size of cells (P=.299), variation coefficient (P=.495), hexagonal cell percent (P=.093) and corneal pachymetry (P=.423). A significant increase of 0.15 Snellen units in BCVA was found during the 3-month follow-up period (P<.001). CONCLUSION: This study shows that after Nd:YAG capsulotomy, BCVA improves significantly without any IOP, OCT or ECA changes during the three-month follow-up. Nd:YAG capsulotomy is a safe procedure in pseudophakic patients without any other ocular pathology.


Assuntos
Opacificação da Cápsula/cirurgia , Lasers de Estado Sólido/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Opacificação da Cápsula/etiologia , Opacificação da Cápsula/patologia , Opacificação da Cápsula/fisiopatologia , Células Endoteliais/patologia , Feminino , Fóvea Central/patologia , Humanos , Pressão Intraocular , Masculino , Neodímio , Procedimentos Cirúrgicos Oftalmológicos/efeitos adversos , Procedimentos Cirúrgicos Oftalmológicos/métodos , Estudos Prospectivos , Pseudofacia/complicações , Tomografia de Coerência Óptica
16.
Neuroimage ; 82: 555-63, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23747286

RESUMO

This study examined the reproducibility of prefrontal-hippocampal connectivity estimates obtained by stochastic dynamic causal modeling (sDCM). 180 healthy subjects were measured by functional magnetic resonance imaging (fMRI) during a standard working memory N-Back task at three different sites (Mannheim, Bonn, Berlin; each with 60 participants). The reproducibility of regional activations in key regions for working memory (dorsolateral prefrontal cortex, DLPFC; hippocampal formation, HF) was evaluated using conjunction analyses across locations. These analyses showed consistent activation of right DLPFC and deactivation of left HF across all three different sites. The effective connectivity between DLPFC and HF was analyzed using a simple two-region sDCM. For each subject, we evaluated sixty-seven alternative sDCMs and compared their relative plausibility using Bayesian model selection (BMS). Across all locations, BMS consistently revealed the same winning model, with the 2-Back working memory condition as driving input to both DLPFC and HF and with a connection from DLPFC to HF. Statistical tests on the sDCM parameter estimates did not show any significant differences across the three sites. The consistency of both the BMS results and model parameter estimates indicates the reliability of sDCM in our paradigm. This provides a basis for future genetic and clinical studies using this approach.


Assuntos
Mapeamento Encefálico/métodos , Hipocampo/fisiologia , Modelos Neurológicos , Vias Neurais/fisiologia , Córtex Pré-Frontal/fisiologia , Adolescente , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Dinâmica não Linear , Reprodutibilidade dos Testes , Adulto Jovem
17.
Acta Biomater ; 9(4): 6169-76, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23237987

RESUMO

Magnetic porous silicon flakes (MPSF) were obtained from mesoporous silicon layers formed by multi-step anodization and subsequent composite formation with Fe oxide nanoparticles by thermal annealing. The magnetic nanoparticles adhered to the surface and penetrated inside the pores. Their structure evolved as a result of the annealing treatments derived from X-ray diffraction and X-ray absorption analyses. Moreover, by tailoring the magnetic load, the dynamic and hydrodynamic properties of the particles were controlled, as observed by the pressure displayed against a sensor probe. Preliminary functionality experiments were performed using an eye model, seeking potential use of MPSF as reinforcement for restored detached retina. It was observed that optimal flake immobilization is obtained when the MPSF reach values of magnetic saturation >10(-4)Am(2)g(-1). Furthermore, the MPSF were demonstrated to be preliminarily biocompatible in vitro. Moreover, New Zealand rabbit in vivo models demonstrated their short-term histocompatibility and their magnetic functionality as retina pressure actuators.


Assuntos
Pressão Intraocular/fisiologia , Nanopartículas de Magnetita/química , Retina/fisiologia , Silício/química , Transdutores de Pressão , Animais , Desenho de Equipamento , Análise de Falha de Equipamento , Calefação , Campos Magnéticos , Porosidade , Coelhos
20.
J Cyst Fibros ; 7(6): 520-2, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18676185

RESUMO

We report three novel CFTR missense mutations detected in Spanish patients from Galicia (North West of Spain). In the first case, a patient homozygous for a novel S1045Y mutation died due to pulmonary problems. In the other two cases, both heterozygous for novel mutations combined with the F508del mutation, clinical symptoms were different depending on the mutation, detected as M595I and A107V.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Mutação de Sentido Incorreto/genética , Adolescente , Adulto , Fibrose Cística/complicações , Fibrose Cística/patologia , Éxons/genética , Feminino , Humanos , Masculino , Espanha
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...