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1.
Opt Express ; 31(2): 1034-1048, 2023 Jan 16.
Article in English | MEDLINE | ID: mdl-36785147

ABSTRACT

This paper presents a discontinuous Galerkin (DG) integral equation (IE) method for the electromagnetic analysis of arbitrarily-shaped plasmonic assemblies. The use of nonconformal meshes provides improved flexibility for CAD prototyping and tessellation of the input geometry. The formulation can readily address nonconformal multi-material junctions (where three or more material regions meet), allowing to set very different mesh sizes depending on the material properties of the different subsystems. It also enables the use of h-refinement techniques to improve accuracy without burdening the computational cost. The continuity of the equivalent electric and magnetic surface currents across the junction contours is enforced by a combination of boundary conditions and local, weakly imposed, interior penalties within the junction regions. A comprehensive study is made to compare the performance of different IE-DG alternatives applied to plasmonics. The numerical experiments conducted validate the accuracy and versatility of this formulation for the resolution of complex nanoparticle assemblies.

3.
Bol. pediatr ; 63(266): 261-267, 2023. tab, graf
Article in Spanish | IBECS | ID: ibc-232442

ABSTRACT

Introducción y objetivos. En las últimas décadas se ha descrito un aumento de la incidencia de enfermedad celíaca (EC) y un predominio de formas de presentación menos sintomáticas. El objetivo de este estudio es describir las características clínicas de la EC en población pediátrica de dos Áreas Sanitarias de Asturias y estimar su incidencia. Pacientes y métodos. Estudio observacional, prospectivo y multicéntrico de pacientes de las Áreas Sanitarias III (Avilés) y V (Gijón) incluidos en el Registro Español de Pacientes Celíacos pediátricos REPAC2 (2011-2017). Se recogieron datos demográficos, síntomas, somatometría y pruebas diagnósticas. Se utilizaron criterios ESPGHAN 2020 para el estudio descriptivo y el cálculo de la incidencia, y criterios ESPGHAN 2012 para el análisis comparativo con el resto de España. Resultados. Se incluyen 99 casos (50,5% niñas): 72 del Área V y 27 del Área III. Mediana de edad: 3,1 años (P25-P75: 1,6-7,7). La forma de presentación más frecuente fue la EC clásica (76,8%), con un 2,0% de asintomáticos. Los síntomas más frecuentes fueron la pérdida/estancamiento de peso (55,7%) y la diarrea (49,5%). Respecto al resto de España (4.681 casos), en Asturias (82 casos) se registró una menor frecuencia de asintomáticos (2,4% vs. 9,8%, p=0,026) y de realización de biopsias (28% vs. 62,1%, p<0,001). La tasa de incidencia de EC basada en diagnósticos hospitalarios fue de 32,1 (IC95%: 26,1-39,1) por 100.000 personas/año. Conclusiones. Se identifican diferencias geográficas en la presentación y diagnóstico de EC, y una mayor incidencia respecto a estudios previos. (AU)


Introduction and aims. Over the last few decades, it has been reported an increase in the incidence of celiac disease (CD) and a predominance of less symptomatic clinical presentations. This study aimed to describe the clinical characteristics of CD in the paediatric population of two Health Areas of Asturias and to estimate its incidence. Patients and methods. Observational, prospective, multicentre study of patients from Health Areas III (Avilés) and V (Gijón) included in the Spanish Registry of Paediatric Celiac Patients REPAC2 (2011-2017). Demographic data, symptoms, somatometry and diagnostic tests were collected. The incidence rate was calculated using the municipal register. ESPGHAN 2020 diagnostic criteria were used for the descriptive study and incidence calculation, and ESPGHAN 2012 criteria were used for the comparative analysis with the rest of Spain. Results. 99 patients (50.5% girls) were included: 72 from Area V and 27 from Area III. Median age: 3.1 years (P25-P75: 1.6-7.7). The most frequent clinical presentation was classic CD (76.8%), whereas 2.0% were asymptomatic. The most frequent symptoms were failure to thrive (55.7%) and diarrhoea (49.5%). Compared with the rest of Spain (4681 patients), Asturias (82 patients) had fewer asymptomatic patients (2.4% vs. 9.8%, p=0.026) and fewer biopsies performed (28% vs. 62.1%, p<0.001). The incidence rate of CD based on hospital diagnoses according to ESPGHAN 2020 criteria was 32.1 (95%CI: 26.1-39.1) per 100,000 person-years. Conclusions. Geographic differences were identified in the presentation and diagnosis of CD, with a higher incidence compared to previous studies. (AU)


Subject(s)
Humans , Child , Celiac Disease , Epidemiology , Diagnosis , General Symptoms , Catchment Area, Health , Spain
4.
Helminthologia ; 57(4): 344-352, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33364903

ABSTRACT

We recorded the metazoan parasite communities in three endemic cichlids (Chiapaheros grammodes, Vieja breidohri and V. hartwegi) collected between November 2008 and July 2009 in the upper Grijalva River Basin (GRB), Chiapas, Mexico. In total, 6,287 individual parasites belonging to 18 taxa (1 monogenean, 6 digeneans, 1 cestode, 4 nematodes, 2 acanthocephalans, 1 hirudinean, 2 copepods and 1 pentastomid) were found. Eleven metazoans were adult forms and 7 larvae; moreover, 14 were endoparasites and 4 ectoparasites. Sixteen parasite taxa represent new geographical and host records. The helminth community in the three cichlids was characterized by higher number of generalists than specialists, as well as a higher proportion of autogenics than allogenics. The metazoan parasites showed prevalence and mean abundances moderate to high. The infracommunities and component community of metazoan parasites had low diversity, richness, and number of individuals and are similar to those reported for other cichlids in Southeastern Mexico, characterized by the presence of typical parasites of cichlids, with a high number of digeneans and generalist parasites. We report the introduced Asian parasitic copepod Neoergasilus japonicus parasitizing endangered or threatened endemic cichlids in the upper GRB. This copepod have been widespread in other freshwater fish species, mainly in Asia (China, India, Japan, Russia, Taiwan), Europe (France, Hungary, Italy, Turkey), and America (Cuba, Mexico, Peru, United States).

8.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 37(6): 397-406, nov.-dic. 2018. ilus, tab
Article in Spanish | IBECS | ID: ibc-178262

ABSTRACT

La enfermedad de Alzheimer (EA) es una enfermedad neurodegenerativa que se caracteriza por un deterioro cognitivo progresivo y pérdida de memoria, siendo la causa más común de demencia. Los hallazgos anatomopatológicos de la EA son los depósitos de Aβ amiloide y proteína Tau, que producen disfunción sináptica y muerte neuronal. La PET amiloide es una técnica útil, disponible y no invasiva que nos proporciona información in vivo del depósito amiloide. En las últimas revisiones de los criterios diagnósticos de la EA se definen e incorporan los biomarcadores, que se clasifican en biomarcadores fisiopatológicos o de diagnóstico (aumento de la retención fibrilar amiloide observada por PET o disminución del péptido Aβ1-42 y elevación de las proteínas T-Tau y F-Tau en el LCR) y biomarcadores de neurodegeneración o topográficos (disminución del metabolismo temporoparietal en la PET-FDG y atrofia temporal medial en la RM). Recientemente se han creado unas recomendaciones específicas para la correcta utilización de los biomarcadores, donde se incluye la PET amiloide: deterioro cognitivo persistente/progresivo, deterioro cognitivo atípico, deterioro cognitivo de inicio precoz y diagnóstico diferencial entre EA y otras enfermedades neurodegenerativas que cursan con demencia. Nuevos estudios de investigación y ensayos clínicos están utilizando la PET amiloide en la evaluación y el desarrollo de nuevas terapias para la EA, así como para el estudio de otras enfermedades neurodegenerativas que cursan con demencia. En este trabajo revisamos algunos conceptos generales y profundizamos en el uso de esta nueva técnica y su relación con las enfermedades neurodegenerativas y el resto de las técnicas diagnósticas


Alzheimer's disease (AD) is a neurodegenerative condition characterized by progressive cognitive decline and memory loss, and is the most common form of dementia. Amyloid plaques with neurofibrillary tangles are a neuropathological hallmark of AD that produces synaptic dysfunction and culminates later in neuronal loss. Amyloid PET is a useful, available and non-invasive technique that provides in vivo information about the cortical amyloid burden. In the latest revised criteria for the diagnosis of AD biomarkers were defined and integrated: pathological and diagnostic biomarkers (increased retention on fibrillar amyloid PET or decreased Aβ1-42 and increased T-Tau or P-Tau in CSF) and neurodegeneration or topographical biomarkers (temporoparietal hypometabolism on 18F-FDG PET and temporal atrophy on MRI). Recently specific recommendations have been created as a consensus statement on the appropriate use of the imaging biomarkers, including amyloid PET: early-onset cognitive impairment/dementia, atypical forms of AD, mild cognitive impairment with early age of onset, and to differentiate between AD and other neurodegenerative diseases that occur with dementia. Amyloid PET is also contributing to the development of new therapies for AD, as well as in research studies for the study of other neurodegenerative diseases that occur with dementia where the deposition of Aβ amyloid is involved in its pathogenesis. In this paper, we review some general concepts and study the use of amyloid PET in depth and its relationship with neurodegenerative diseases and other diagnostic techniques


Subject(s)
Humans , Single Photon Emission Computed Tomography Computed Tomography/methods , Amyloidosis/diagnostic imaging , Alzheimer Disease/diagnostic imaging , Cognitive Dysfunction/diagnostic imaging , Neuroimaging/methods , Neurodegenerative Diseases/diagnostic imaging , Radiopharmaceuticals
9.
Article in English, Spanish | MEDLINE | ID: mdl-29776894

ABSTRACT

Alzheimer's disease (AD) is a neurodegenerative condition characterized by progressive cognitive decline and memory loss, and is the most common form of dementia. Amyloid plaques with neurofibrillary tangles are a neuropathological hallmark of AD that produces synaptic dysfunction and culminates later in neuronal loss. Amyloid PET is a useful, available and non-invasive technique that provides in vivo information about the cortical amyloid burden. In the latest revised criteria for the diagnosis of AD biomarkers were defined and integrated: pathological and diagnostic biomarkers (increased retention on fibrillar amyloid PET or decreased Aß1-42 and increased T-Tau or P-Tau in CSF) and neurodegeneration or topographical biomarkers (temporoparietal hypometabolism on 18F-FDG PET and temporal atrophy on MRI). Recently specific recommendations have been created as a consensus statement on the appropriate use of the imaging biomarkers, including amyloid PET: early-onset cognitive impairment/dementia, atypical forms of AD, mild cognitive impairment with early age of onset, and to differentiate between AD and other neurodegenerative diseases that occur with dementia. Amyloid PET is also contributing to the development of new therapies for AD, as well as in research studies for the study of other neurodegenerative diseases that occur with dementia where the deposition of Aß amyloid is involved in its pathogenesis. In this paper, we review some general concepts and study the use of amyloid PET in depth and its relationship with neurodegenerative diseases and other diagnostic techniques.


Subject(s)
Alzheimer Disease/diagnostic imaging , Positron-Emission Tomography , Amyloid beta-Peptides , Humans , Positron-Emission Tomography/methods , Practice Guidelines as Topic
12.
Radiología (Madr., Ed. impr.) ; 60(2): 171-174, mar.-abr. 2018. ilus
Article in Spanish | IBECS | ID: ibc-174079

ABSTRACT

La inflamación de las glándulas salivales secundaria a la administración de contraste yodado es una reacción adversa muy poco frecuente. Su etiología no está aclarada y, aunque tiene un curso benigno, se han descrito complicaciones asociadas. Presentamos dos casos de submaxilitis aguda bilateral como reacción adversa tras la administración intravenosa de contraste yodado en dos varones de 60 y 63 años de edad a los que se realizó en los días previos una tomografía computarizada


Swelling of the salivary glands after administration of iodinated contrast is a very rare adverse reaction. Its etiology is not clear and although it has a benign course associated complications have been reported. We report two cases of acute bilateral sialadenitis after intravenous iodinated contrast in 60 and 63 year-old men who underwent a computed tomography scan in the previous days


Subject(s)
Humans , Male , Middle Aged , Sialadenitis/complications , Sialadenitis/diagnostic imaging , Iodine Compounds/adverse effects , Adrenal Cortex Hormones/therapeutic use , Sialadenitis/chemically induced , Salivary Glands , Salivary Glands/diagnostic imaging , Contrast Media/adverse effects , Cervical Vertebrae/diagnostic imaging , Cervical Vertebrae/injuries , Diagnosis, Differential
13.
Radiologia (Engl Ed) ; 60(2): 171-174, 2018.
Article in English, Spanish | MEDLINE | ID: mdl-28619517

ABSTRACT

Swelling of the salivary glands after administration of iodinated contrast is a very rare adverse reaction. Its etiology is not clear and although it has a benign course associated complications have been reported. We report two cases of acute bilateral sialadenitis after intravenous iodinated contrast in 60 and 63 year-old men who underwent a computed tomography scan in the previous days.


Subject(s)
Contrast Media/adverse effects , Iohexol/adverse effects , Sialadenitis/chemically induced , Humans , Male , Middle Aged
14.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 36(4): 219-226, jul.-ago. 2017. tab, graf
Article in Spanish | IBECS | ID: ibc-163738

ABSTRACT

Objetivo. conocer la situación de los estudios de neuroimagen de Medicina Nuclear que se realizaron en España en el año 2013 y primer trimestre del 2014, con el fin de definir las actividades del grupo de trabajo de Neuroimagen de la Sociedad Española de Medicina Nuclear e Imagen Molecular (SEMNIM). Material y métodos. Se diseñó un cuestionario de 14 preguntas dividido en 3 partes: características de los servicios (equipamiento y profesionales involucrados), tipo de exploraciones e indicaciones clínicas y métodos de evaluación. El cuestionario se remitió a los 166 servicios de Medicina Nuclear que figuraban en la secretaría de la Sociedad Española de Medicina Nuclear e Imagen Molecular. Resultados. Respondieron a la encuesta un total de 54 centros distribuidos entre todas las comunidades autónomas. La mayoría de los centros realizaron entre 300 y 800 exploraciones de neuroimagen al año, representando más de 25 exploraciones al mes. La media de equipos por servicio era de 3, teniendo la mitad de ellos equipos PET/TC y SPECT/TC. Las exploraciones realizadas con más frecuencia son la SPECT cerebral con 123I-FP-CIT, seguida de la SPECT cerebral de perfusión y de la PET con 18F-FDG, siendo las indicaciones clínicas más frecuentes los estudios de deterioro cognitivo seguidos por los de trastornos del movimiento. Para la evaluación de las pruebas la mayoría de los centros utilizaron únicamente la valoración visual, en la valoración cuantitativa la cuantificación por regiones de interés fue la más utilizada. Conclusiones. Los resultados reflejan cuál fue la actividad clínica del año 2013 y primer trimestre del 2014, siendo las indicaciones principales los estudios de deterioro cognitivo y trastorno del movimiento. La variabilidad en la evaluación de los estudios PET y la colaboración con los especialistas clínicos que demandan las exploraciones de neuroimagen de Medicina Nuclear son algunos de los retos que debemos afrontar en los próximos años (AU)


Objective. To determine the status of neuroimaging studies of Nuclear Medicine in Spain during 2013 and first quarter of 2014, in order to define the activities of the neuroimaging group of the Spanish Society of Nuclear Medicine and Molecular Imaging (SEMNIM). Material and methods. A questionnaire of 14 questions was designed, divided into 3 parts: characteristics of the departments (equipment and professionals involved); type of scans and clinical indications; and evaluation methods. The questionnaire was sent to 166 Nuclear Medicine departments. Results. A total of 54 departments distributed among all regions completed the questionnaire. Most departments performed between 300 and 800 neuroimaging examinations per year, representing more than 25 scans per month. The average pieces of equipment were three; half of the departments had a PET/CT scanner and SPECT/CT equipment. Scans performed more frequently were brain SPECT with 123I-FP-CIT, followed by brain perfusion SPECT and PET with 18F-FDG. The most frequent clinical indications were cognitive impairment followed by movement disorders. For evaluation of the images most sites used only visual assessment, and for the quantitative assessment the most used was quantification by region of interest. Conclusions. These results reflect the clinical activity of 2013 and first quarter of 2014. The main indications of the studies were cognitive impairment and movement disorders. Variability in the evaluation of the studies is among the challenges that will be faced in the coming years (AU)


Subject(s)
Humans , Nuclear Medicine/trends , Neuroimaging/methods , Neuroimaging/trends , Positron-Emission Tomography/trends , Tomography, Emission-Computed, Single-Photon/trends , Societies, Medical/organization & administration , Societies, Medical/standards , Surveys and Questionnaires , Nuclear Medicine/education , Nuclear Medicine , Nervous System Diseases/classification , Nervous System Diseases , Movement Disorders , Cognition Disorders
16.
Rev Esp Med Nucl Imagen Mol ; 36(4): 219-226, 2017.
Article in English, Spanish | MEDLINE | ID: mdl-28237122

ABSTRACT

OBJECTIVE: To determine the status of neuroimaging studies of Nuclear Medicine in Spain during 2013 and first quarter of 2014, in order to define the activities of the neuroimaging group of the Spanish Society of Nuclear Medicine and Molecular Imaging (SEMNIM). MATERIAL AND METHODS: A questionnaire of 14 questions was designed, divided into 3 parts: characteristics of the departments (equipment and professionals involved); type of scans and clinical indications; and evaluation methods. The questionnaire was sent to 166 Nuclear Medicine departments. RESULTS: A total of 54 departments distributed among all regions completed the questionnaire. Most departments performed between 300 and 800 neuroimaging examinations per year, representing more than 25 scans per month. The average pieces of equipment were three; half of the departments had a PET/CT scanner and SPECT/CT equipment. Scans performed more frequently were brain SPECT with 123I-FP-CIT, followed by brain perfusion SPECT and PET with 18F-FDG. The most frequent clinical indications were cognitive impairment followed by movement disorders. For evaluation of the images most sites used only visual assessment, and for the quantitative assessment the most used was quantification by region of interest. CONCLUSIONS: These results reflect the clinical activity of 2013 and first quarter of 2014. The main indications of the studies were cognitive impairment and movement disorders. Variability in the evaluation of the studies is among the challenges that will be faced in the coming years.


Subject(s)
Neuroimaging/trends , Nuclear Medicine Department, Hospital/statistics & numerical data , Nuclear Medicine/trends , Cognition Disorders/diagnostic imaging , Durable Medical Equipment/statistics & numerical data , Epilepsy/diagnostic imaging , Humans , Mental Disorders/diagnostic imaging , Movement Disorders/diagnostic imaging , Nervous System Diseases/diagnostic imaging , Neuroimaging/instrumentation , Neuroimaging/statistics & numerical data , Radionuclide Imaging/statistics & numerical data , Radiopharmaceuticals , Spain , Surveys and Questionnaires , Workforce
18.
Bol. pediatr ; 57(242): 275-280, 2017. graf, tab
Article in Spanish | IBECS | ID: ibc-172059

ABSTRACT

Objetivo: Evaluar la eficacia de un preparado lácteo suplementado con fibra en niños con estreñimiento funcional. Material y métodos: Ensayo clínico, aleatorizado, doble ciego, controlado con placebo. Se incluyeron 19 niños de entre 4 y 12 años con criterios de Roma III para estreñimiento funcional. El grupo de intervención recibió durante 4 semanas 200 ml al día de leche con fibra, mientras los controles recibieron una ración similar de leche sin suplementar. Resultados: Tras 4 semanas no se encontraron diferencias estadísticamente significativas entre grupos respecto a la realización de al menos 3 deposiciones a la semana (88,9% en tratados frente a 100% en controles, p = 0,474), número de deposiciones semanales, consistencia de deposiciones o presencia de conductas de retención, dolor con la defecación e incontinencia fecal, o la salud autopercibida. En ambos se observó tendencia al aumento en el número de deposiciones; en el grupo de tratamiento de 3,6 ± 1,9 a 5,8 ± 2,0 deposiciones/semana (p = 0,059) y en el grupo placebo de 3,3 ± 1,3 a 5,8 ± 1,3 deposiciones/semana (p = 0,001). También disminuyó la presencia de dolor con la defecación en el grupo de tratamiento del 77,8% al 11,1% (p = 0,031) y en placebo del 80,0% al 20,0% (p = 0,031). Conclusiones: No se ha podido confirmar la eficacia de un preparado lácteo con fibra para el estreñimiento funcional infantil. Son necesarios estudios bien diseñados y de mayor tamaño muestral para determinar el papel de los suplementos de fibra en los niños con estreñimiento


Objective: To assess the effectiveness of a fibre-fortified milk in children with chronic functional constipation. Patients and methods: Randomised, double-blind, placebo-controlled clinical trial involving 19 children, 4 to 12-year-old, who were diagnosis with functional constipation according to Rome III Criteria. Intervention group received 200 ml of fibre-fortified milk daily for 4 weeks, while the other group received a similar portion of nonfortified milk. Results: At the end of the intervention there were no statistically significant differences between groups with respect to having at least three bowel movements a week (88.9% in intervention group vs. 100% in control group, p = 0.474), frequency of bowel movements, stool consistency, presence of painful defecation, retentive posturing, or fecal incontinence, or self-reported perceived health. Both groups tended to increase bowel movements. Fibre group increased from 3.6 ± 1.9 to 5.8 ± 2.0 bowel movements/week (p = 0.059), while control group increased from 3.3 ± 1.3 to 5.8 ± 1.3 bowel movements/week (p = 0.001). Presence of painful defecation decreased both in fibre group, 77.8% to 11.1% (p = 0.031), and in control group, 80.0% to 20,0% (p = 0.031). Conclusions: Effectiveness of a fibre-fortified milk was not confirmed in children with chronic functional constipation. High quality clinical trials are required to know the efficacy of fibre supplements in children with functional constipation


Subject(s)
Humans , Male , Female , Child, Preschool , Child , Adolescent , Dairy Products , Constipation/diet therapy , Dietary Fiber , Inulin/therapeutic use , Double-Blind Method , Placebos/therapeutic use , Clinical Protocols , Feeding Behavior/physiology
19.
Radiología (Madr., Ed. impr.) ; 58(2): 148-151, mar.-abr. 2016.
Article in Spanish | IBECS | ID: ibc-150618

ABSTRACT

Los adenomiomas gástricos son tumores benignos extremadamente infrecuentes en la población pediátrica, cuya histología recuerda al componente epitelial de los conductos pancreáticos. Presentamos un caso de un adenomioma pilórico que simuló clínicamente una estenosis hipertrófica de píloro en una niña recién nacida. Las pruebas radiológicas, fundamentalmente la resonancia magnética, fueron muy importantes en la caracterización y el diagnóstico de esta entidad (AU)


Gastric adenomyomas are extremely uncommon benign tumors in children. On histologic examination, these tumors have an epithelial component similar to pancreatic ducts. We present a case of a pyloric adenomyoma that clinically simulated hypertrophic pyloric stenosis in a newborn girl. Imaging tests, fundamentally magnetic resonance imaging, were very important in the characterization and diagnosis of this entity (AU)


Subject(s)
Humans , Female , Infant , Adenomyoma , Pyloric Stenosis, Hypertrophic/complications , Pyloric Stenosis, Hypertrophic , Diagnosis, Differential , Pylorus/pathology , Pylorus , Magnetic Resonance Imaging/methods , Magnetic Resonance Spectroscopy/methods , Ultrasonography , Anatomy, Cross-Sectional/methods
20.
Radiologia ; 58(2): 148-51, 2016.
Article in Spanish | MEDLINE | ID: mdl-26837724

ABSTRACT

Gastric adenomyomas are extremely uncommon benign tumors in children. On histologic examination, these tumors have an epithelial component similar to pancreatic ducts. We present a case of a pyloric adenomyoma that clinically simulated hypertrophic pyloric stenosis in a newborn girl. Imaging tests, fundamentally magnetic resonance imaging, were very important in the characterization and diagnosis of this entity.


Subject(s)
Adenomyoma/diagnostic imaging , Pyloric Stenosis, Hypertrophic/diagnostic imaging , Female , Humans , Infant, Newborn , Pylorus/physiopathology
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