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1.
Ann Neurol ; 95(6): 1058-1068, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38466157

RESUMEN

OBJECTIVE: Along with the known effects of stress on brain structure and inflammatory processes, increasing evidence suggest a role of chronic stress in the pathogenesis of Alzheimer's disease (AD). We investigated the association of accumulated stressful life events (SLEs) with AD pathologies, neuroinflammation, and gray matter (GM) volume among cognitively unimpaired (CU) individuals at heightened risk of AD. METHODS: This cross-sectional cohort study included 1,290 CU participants (aged 48-77) from the ALFA cohort with SLE, lumbar puncture (n = 393), and/or structural magnetic resonance imaging (n = 1,234) assessments. Using multiple regression analyses, we examined the associations of total SLEs with cerebrospinal fluid (1) phosphorylated (p)-tau181 and Aß1-42/1-40 ratio, (2) interleukin 6 (IL-6), and (3) GM volumes voxel-wise. Further, we performed stratified and interaction analyses with sex, history of psychiatric disease, and evaluated SLEs during specific life periods. RESULTS: Within the whole sample, only childhood and midlife SLEs, but not total SLEs, were associated with AD pathophysiology and neuroinflammation. Among those with a history of psychiatric disease SLEs were associated with higher p-tau181 and IL-6. Participants with history of psychiatric disease and men, showed lower Aß1-42/1-40 with higher SLEs. Participants with history of psychiatric disease and women showed reduced GM volumes in somatic regions and prefrontal and limbic regions, respectively. INTERPRETATION: We did not find evidence supporting the association of total SLEs with AD, neuroinflammation, and atrophy pathways. Instead, the associations appear to be contingent on events occurring during early and midlife, sex and history of psychiatric disease. ANN NEUROL 2024;95:1058-1068.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Encéfalo , Enfermedades Neuroinflamatorias , Proteínas tau , Humanos , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/diagnóstico por imagen , Femenino , Masculino , Anciano , Persona de Mediana Edad , Estudios Transversales , Estudios de Cohortes , Encéfalo/patología , Encéfalo/diagnóstico por imagen , Enfermedades Neuroinflamatorias/patología , Enfermedades Neuroinflamatorias/diagnóstico por imagen , Péptidos beta-Amiloides/líquido cefalorraquídeo , Péptidos beta-Amiloides/metabolismo , Proteínas tau/líquido cefalorraquídeo , Imagen por Resonancia Magnética , Estrés Psicológico , Sustancia Gris/patología , Sustancia Gris/diagnóstico por imagen , Interleucina-6/líquido cefalorraquídeo , Fragmentos de Péptidos/líquido cefalorraquídeo
2.
Pediatr Radiol ; 54(7): 1116-1127, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38644431

RESUMEN

BACKGROUND: PTEN-related hamartoma tumor syndrome results from a mutation in the PTEN gene located at 10q23.31. This syndrome represents a spectrum of different phenotypes of variable expressions, now recognized as part of the same condition. Patients with this mutation have an increased risk of developing a wide range of findings, including malignancies. Although widely described in adults, there are no large series describing the imaging findings in patients before adulthood. Knowledge of the findings seen in children and adolescents with PTEN-related hamartoma tumor syndrome can help guide further management and improve surveillance recommendations. OBJECTIVE: To describe the spectrum of imaging abnormalities in pediatric patients with PTEN-related hamartoma tumor syndrome. MATERIALS AND METHODS: We performed a retrospective, cross-sectional, multicenter study conducted between January 2000 and October 2021 in three tertiary pediatric institutions evaluating the imaging findings in children and adolescents (≤ 18 years) with confirmed diagnoses of a PTEN mutation. For each patient, the imaging findings, histopathology reports, and at least a 2-year follow-up of clinical outcomes for non-operative cases were documented. RESULTS: The cohort included 78 children (37 girls), with a mean age at diagnosis of 7.5 years (range 0 days to 18 years). Benign brain findings included enlarged Virchow-Robin perivascular spaces, white matter changes, developmental venous anomalies, and cerebellar hamartomas. Benign thyroid findings were common, but 5/45 (11.1%) with thyroid abnormalities had a malignant nodule. Soft tissue adipocytic tumors, GI/GU polyps, other soft tissue abnormalities, along with vascular anomalies in various anatomic locations were common. CONCLUSION: Brain abnormalities, benign non-vascular soft tissue abnormalities, and vascular anomalies are commonly seen in children and adolescents with PTEN-related hamartoma tumor syndrome. However, malignancies involving the thyroid gland are not uncommon. Familiarity with the phenotype of PTEN-related hamartoma tumor syndrome in the pediatric population can improve diagnosis and prompt appropriate clinical surveillance of abnormal findings that warrant further management.


Asunto(s)
Síndrome de Hamartoma Múltiple , Fosfohidrolasa PTEN , Humanos , Femenino , Masculino , Niño , Estudios Retrospectivos , Adolescente , Síndrome de Hamartoma Múltiple/diagnóstico por imagen , Síndrome de Hamartoma Múltiple/genética , Estudios Transversales , Preescolar , Fosfohidrolasa PTEN/genética , Lactante , Mutación
3.
Sensors (Basel) ; 24(4)2024 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-38400475

RESUMEN

In this work, an exhaustive analysis of the partial discharges that originate in the bubbles present in dielectric mineral oils is carried out. To achieve this, a low-cost, high-resolution CMOS image sensor is used. Partial discharge measurements using that image sensor are validated by a standard electrical detection system that uses a discharge capacitor. In order to accurately identify the images corresponding to partial discharges, a convolutional neural network is trained using a large set of images captured by the image sensor. An image classification model is also developed using deep learning with a convolutional network based on a TensorFlow and Keras model. The classification results of the experiments show that the accuracy achieved by our model is around 95% on the validation set and 82% on the test set. As a result of this work, a non-destructive diagnosis method has been developed that is based on the use of an image sensor and the design of a convolutional neural network. This approach allows us to obtain information about the state of mineral oils before breakdown occurs, providing a valuable tool for the evaluation and maintenance of these dielectric oils.

4.
Rev Esp Enferm Dig ; 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38305675

RESUMEN

We present the case of a 41-year-old patient under study for chronic diarrhea, iron deficiency, and elevated fecal calprotectin. After ileocolonoscopy, magnetic resonance and capsule endoscopy without alterations, an upper endoscopy was performed visualizing fibrinated serpinginous ulcers, confluent with each other, with erythematous mucosa between them, suggestive of isolated gastric Crohn's disease, a rare entity in the adult population.

5.
Rev Esp Enferm Dig ; 1182024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39087657

RESUMEN

We present 4 clinical cases of intestinal spirochetosis. The first one presents with chronic diarrhea, and spirochetes are detected in random biopsies. The second is homosexual, HIV+, presents rectal bleeding, colonoscopy shows a straight ulcer and spirochete biopsies show negative treponema PCR. The third was also homosexual, HIV+, asymptomatic, with a chance finding of spirochetosis. The last case is also a chance histological diagnosis in a patient with inactive ulcerative colitis without lesions. Intestinal spirochetosis appears to be transmitted sexually and by consumption of contaminated water. The majority are asymptomatic cases but could cause lesions including ulcerations and symptoms. Treatment is only recommended in symptomatic or immunosuppressed patients. It must be distinguished from lesions caused by Treponema pallidum.

6.
Rev Esp Enferm Dig ; 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38469818

RESUMEN

We present the case of a patient with smoking, alcoholism, cirrhosis and HIV who was endoscopically diagnosed with esophageal candidiasis due to an episode of dysphagia. After treatment with antifungals and PPIs, the patient remained asymptomatic for almost 3 years. He presented an event of food impaction that was resolved by an upper endoscopy in which an esophageal stenosis and multiple esophageal pseudodiverticulosis were visualized. The biopsies only showed chronic nonspecific esophagitis. The stenosis was dilated with a balloon and PPIs were continued, with good response. Esophageal intramural pseudodiverticulosis is rare and can lead to motor disorders and strictures. It has a doubtful association with HIV and a clearer relationship with alcoholism, smoking, diabetes, reflux and candidiasis. The endoscopic diagnosis can be difficult so in order to make an accurate diagnosis is necessary an esophagram or CT. Treatment is based on controlling risk factors and dilating stenosis. The prognosis is usually favorable.

7.
Neuroimage ; 265: 119761, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36455762

RESUMEN

Accurate measurement of Alzheimer's disease (AD) pathology in older adults without significant clinical impairment is critical to assessing intervention strategies aimed at slowing AD-related cognitive decline. The U.S. Study to Protect Brain Health Through Lifestyle Intervention to Reduce Risk (POINTER) is a 2-year randomized controlled trial to evaluate the effect of multicomponent risk reduction strategies in older adults (60-79 years) who are cognitively unimpaired but at increased risk for cognitive decline/dementia due to factors such as cardiovascular disease and family history. The POINTER Imaging ancillary study is collecting tau-PET ([18F]MK6240), beta-amyloid (Aß)-PET ([18F]florbetaben [FBB]) and MRI data to evaluate neuroimaging biomarkers of AD and cerebrovascular pathophysiology in this at-risk sample. Here 481 participants (70.0±5.0; 66% F) with baseline MK6240, FBB and structural MRI scans were included. PET scans were coregistered to the structural MRI which was used to create FreeSurfer-defined reference regions and target regions of interest (ROIs). We also created off-target signal (OTS) ROIs to examine the magnitude and distribution of MK6240 OTS across the brain as well as relationships between OTS and age, sex, and race. OTS was unimodally distributed, highly correlated across OTS ROIs and related to younger age and sex but not race. Aiming to identify an optimal processing approach for MK6240 that would reduce the influence of OTS, we compared our previously validated MRI-guided standard PET processing and 6 alternative approaches. The alternate approaches included combinations of reference region erosion and meningeal OTS masking before spatial smoothing as well as partial volume correction. To compare processing approaches we examined relationships between target ROIs (entorhinal cortex (ERC), hippocampus or a temporal meta-ROI (MetaROI)) SUVR and age, sex, race, Aß and a general cognitive status measure, the Modified Telephone Interview for Cognitive Status (TICSm). Overall, the processing approaches performed similarly, and none showed a meaningful improvement over standard processing. Across processing approaches we observed previously reported relationships with MK6240 target ROIs including positive associations with age, an Aß+> Aß- effect and negative associations with cognition. In sum, we demonstrated that different methods for minimizing effects of OTS, which is highly correlated across the brain within subject, produced no substantive change in our performance metrics. This is likely because OTS contaminates both reference and target regions and this contamination largely cancels out in SUVR data. Caution should be used when efforts to reduce OTS focus on target or reference regions in isolation as this may exacerbate OTS contamination in SUVR data.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Anciano , Humanos , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/patología , Tomografía de Emisión de Positrones/métodos , Proteínas tau/metabolismo , Persona de Mediana Edad
8.
Pediatr Blood Cancer ; 70 Suppl 4: e29955, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36083866

RESUMEN

Cardiac tumors in children are rare and the majority are benign. The most common cardiac tumor in children is rhabdomyoma, usually associated with tuberous sclerosis complex. Other benign cardiac masses include fibromas, myxomas, hemangiomas, and teratomas. Primary malignant cardiac tumors are exceedingly rare, with the most common pathology being soft tissue sarcomas. This paper provides consensus-based imaging recommendations for the evaluation of patients with cardiac tumors at diagnosis and follow-up, including during and after therapy.


Asunto(s)
Neoplasias Cardíacas , Rabdomioma , Esclerosis Tuberosa , Niño , Humanos , Resonancia por Plasmón de Superficie , Neoplasias Cardíacas/diagnóstico por imagen , Neoplasias Cardíacas/complicaciones , Rabdomioma/diagnóstico por imagen , Rabdomioma/complicaciones , Diagnóstico por Imagen
9.
Pediatr Radiol ; 53(5): 1019-1026, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36585499

RESUMEN

Ectopia cordis is a rare congenital defect with high mortality, and it remains challenging to radiologists, neonatologists and surgeons. CT angiography provides key information that aids in the decision-making process for possible surgical intervention. This pictorial essay describes CT angiography features in six neonates with ectopia cordis.


Asunto(s)
Ectopía Cordis , Cardiopatías Congénitas , Recién Nacido , Humanos , Niño , Ectopía Cordis/diagnóstico por imagen , Ectopía Cordis/cirugía , Angiografía por Tomografía Computarizada , Angiografía , Tomografía Computarizada por Rayos X , Cardiopatías Congénitas/cirugía
10.
Pediatr Radiol ; 53(2): 297-312, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36161506

RESUMEN

The indications for fetal body MRI are amplifying because of the expanding possibilities of fetal and perinatal therapy. However, huge heterogeneity regarding the indications for fetal body MRI is seen among different European countries that is mostly related to local use of US, but also to local fetal MRI expertise and legislation on pregnancy termination. The purpose of this article is to summarize the precise indications for fetal MRI, excluding the central nervous system. MRI indications arise from the sonographic findings, based on the operator's experience and the various practices in the countries and institutions represented on the European Society of Paediatric Radiology Fetal Task Force. We also highlight the strengths and weaknesses of fetal US and MRI of the fetal body.


Asunto(s)
Aborto Inducido , Ultrasonografía Prenatal , Embarazo , Femenino , Niño , Humanos , Ultrasonografía Prenatal/métodos , Sistema Nervioso Central , Feto , Imagen por Resonancia Magnética/métodos , Diagnóstico Prenatal/métodos
11.
Pediatr Radiol ; 53(4): 677-694, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36334120

RESUMEN

Congenital heart disease affects approximately 1% of live births per year. In recent years, there has been a decrease in the morbidity and mortality of these cases due to advances in medical and surgical care. Imaging plays a key role in the management of these children, with chest radiography, echocardiography and chest ultrasound the first diagnostic tools, and cardiac computed tomography, catheterization and magnetic resonance imaging reserved to assess better the anatomy and physiology of the most complex cases. This article is a beginner's guide to the anatomy of the most frequent congenital heart diseases (atrial and ventricular septal defects, abnormal pulmonary venous connections, univentricular heart, tetralogy of Fallot, transposition of the great arteries and coarctation of the aorta), their surgical management, the most common postsurgical complications, deciding which imaging modality is needed, and when and how to image gently.


Asunto(s)
Cardiopatías Congénitas , Defectos del Tabique Interventricular , Transposición de los Grandes Vasos , Niño , Humanos , Transposición de los Grandes Vasos/diagnóstico por imagen , Transposición de los Grandes Vasos/cirugía , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/cirugía , Defectos del Tabique Interventricular/diagnóstico , Defectos del Tabique Interventricular/cirugía , Ecocardiografía , Imagen por Resonancia Magnética
12.
Pediatr Radiol ; 53(4): 660-676, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36138217

RESUMEN

Advanced cardiorespiratory imaging of the chest with ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) plays an important role in diagnosing respiratory and cardiac conditions in neonates when radiography and echocardiography alone are not sufficient. This pictorial essay highlights the particularities, clinical indications and technical aspects of applying chest US, cardiac CT and cardiorespiratory MRI techniques specifically to neonates, summarising the first session of the European Society of Paediatric Radiology's cardiothoracic task force.


Asunto(s)
Cardiopatías , Recién Nacido , Niño , Humanos , Imagen Multimodal/métodos , Tomografía Computarizada por Rayos X , Ecocardiografía , Imagen por Resonancia Magnética
13.
Pediatr Radiol ; 53(9): 1829-1841, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37039913

RESUMEN

Fetal magnetic resonance imaging (MRI) is increasingly being used worldwide as a complementary tool to prenatal ultrasound (US) for multiple fetal pathologies. The aim of this article is to describe and illustrate how MRI can help US to evaluate fetal abdominal anomalies, based on cases performed in a tertiary public university hospital. Prenatal US, fetal MRI and postnatal imaging of these cases will be shown side-by-side to describe and illustrate the added value of fetal MRI in the different organs/systems and its impact on clinical management.


Asunto(s)
Diagnóstico Prenatal , Ultrasonografía Prenatal , Embarazo , Femenino , Humanos , Diagnóstico Prenatal/métodos , Ultrasonografía Prenatal/métodos , Imagen por Resonancia Magnética/métodos , Abdomen/diagnóstico por imagen , Feto , Estudios Retrospectivos
14.
Pediatr Radiol ; 53(10): 2120-2133, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37202498

RESUMEN

Anomalous pulmonary venous connections represent a heterogeneous group of congenital heart diseases in which a part or all pulmonary venous flow drains directly or indirectly into the right atrium. Clinically, anomalous pulmonary venous connections may be silent or have variable consequences, including neonatal cyanosis, volume overload and pulmonary arterial hypertension due to the left-to-right shunt. Anomalous pulmonary venous connections are frequently associated with other congenital cardiac defects and their accurate diagnosis is crucial for treatment planning. Therefore, multimodality diagnostic imaging, comprising a combination (but not all) of echocardiography, cardiac catheterization, cardiothoracic computed tomography and cardiac magnetic resonance imaging, helps identify potential blind spots relevant to each imaging modality before treatment and achieve optimal management and monitoring. For the same reasons, diagnostic imaging evaluation using a multimodality fashion should be used after treatment. Finally, those interpreting the images should be familiar with the various surgical approaches used to repair anomalous pulmonary venous connections and the common postoperative complications.


Asunto(s)
Cardiopatías Congénitas , Venas Pulmonares , Síndrome de Cimitarra , Recién Nacido , Humanos , Síndrome de Cimitarra/cirugía , Cardiopatías Congénitas/diagnóstico por imagen , Corazón , Venas Pulmonares/diagnóstico por imagen , Venas Pulmonares/anomalías , Tomografía Computarizada por Rayos X
15.
Pediatr Radiol ; 53(10): 2106-2119, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37166455

RESUMEN

Congenital thoracic anomalies are uncommon malformations that require a precise diagnosis to guide parental counseling and possible prenatal treatment. Prenatal ultrasound (US) is the gold standard imaging modality to first detect and characterize these abnormalities and the best modality for follow-up. Fetal magnetic resonance imaging (MRI) is a complementary tool that provides multiplanar assessment and tissue characterization and can help estimate prognosis. Prenatal treatment is increasingly being used in fetuses with signs of distress and to potentially decrease morbidity and mortality. In this essay, the authors illustrate side-by-side US, MRI and therapeutic options for congenital thoracic anomalies in cases that presented to a tertiary pediatric hospital during the 7-year period 2014-2021. Entities included are congenital diaphragmatic hernia, congenital pulmonary airway malformation, bronchopulmonary sequestration, hybrid lesions, foregut duplications cysts and congenital lobar overinflation. Treatment options include maternal steroids, thoraco-amniotic shunt and fetal endotracheal occlusion. Recognition of typical findings in congenital thoracic anomalies is helpful to establish diagnosis, predict prognosis and plan perinatal treatment.


Asunto(s)
Malformación Adenomatoide Quística Congénita del Pulmón , Hernias Diafragmáticas Congénitas , Embarazo , Femenino , Humanos , Niño , Diagnóstico Prenatal/métodos , Hernias Diafragmáticas Congénitas/diagnóstico por imagen , Hernias Diafragmáticas Congénitas/cirugía , Imagen por Resonancia Magnética/métodos , Ultrasonografía Prenatal/métodos
16.
Pediatr Radiol ; 53(12): 2323-2344, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37674051

RESUMEN

Children living with achondroplasia are at an increased risk of developing neurological complications, which may be associated with acute and life-altering events. To remediate this risk, the timely acquisition of effective neuroimaging that can help to guide clinical management is essential. We propose imaging protocols and follow-up strategies for evaluating the neuroanatomy of these children and to effectively identify potential neurological complications, including compression at the cervicomedullary junction secondary to foramen magnum stenosis, spinal deformity and spinal canal stenosis. When compiling these recommendations, emphasis has been placed on reducing scan times and avoiding unnecessary radiation exposure. Standardized imaging protocols are important to ensure that clinically useful neuroimaging is performed in children living with achondroplasia and to ensure reproducibility in future clinical trials. The members of the European Society of Pediatric Radiology (ESPR) Neuroradiology Taskforce and European Society of Neuroradiology pediatric subcommittee, together with clinicians and surgeons with specific expertise in achondroplasia, wrote this opinion paper. The research committee of the ESPR also endorsed the final draft. The rationale for these recommendations is based on currently available literature, supplemented by best practice opinion from radiologists and clinicians with subject-specific expertise.


Asunto(s)
Acondroplasia , Radiología , Niño , Humanos , Lactante , Foramen Magno/cirugía , Reproducibilidad de los Resultados , Constricción Patológica , Acondroplasia/diagnóstico por imagen
17.
Pediatr Radiol ; 53(12): 2539-2551, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37682330

RESUMEN

OBJECTIVE: To investigate the feasibility of diffusion-weighted magnetic resonance imaging (DW-MRI) as a predictive imaging marker after neoadjuvant chemotherapy in patients with rhabdomyosarcoma. MATERIAL AND METHODS: We performed a multicenter retrospective study including pediatric, adolescent and young adult patients with rhabdomyosarcoma, Intergroup Rhabdomyosarcoma Study group III/IV, treated according to the European paediatric Soft tissue sarcoma Study Group (EpSSG) RMS2005 or MTS2008 studies. DW-MRI was performed according to institutional protocols. We performed two-dimensional single-slice tumor delineation. Areas of necrosis or hemorrhage were delineated to be excluded in the primary analysis. Mean, median and 5th and 95th apparent diffusion coefficient (ADC) were extracted. RESULTS: Of 134 included patients, 82 had measurable tumor at diagnosis and response and DW-MRI scans of adequate quality and were included in the analysis. Technical heterogeneity in scan acquisition protocols and scanners was observed. Mean ADC at diagnosis was 1.1 (95% confidence interval [CI]: 1.1-1.2) (all ADC expressed in * 10-3 mm2/s), versus 1.6 (1.5-1.6) at response assessment. The 5th percentile ADC was 0.8 (0.7-0.9) at diagnosis and 1.1 (1.0-1.2) at response. Absolute change in mean ADC after neoadjuvant chemotherapy was 0.4 (0.3-0.5). Exploratory analyses for association between ADC and clinical parameters showed a significant difference in mean ADC at diagnosis for alveolar versus embryonal histology. Landmark analysis at nine weeks after the date of diagnosis showed no significant association (hazard ratio 1.3 [0.6-3.2]) between the mean ADC change and event-free survival. CONCLUSION: A significant change in the 5th percentile and the mean ADC after chemotherapy was observed. Strong heterogeneity was identified in DW-MRI acquisition protocols between centers and in individual patients.


Asunto(s)
Rabdomiosarcoma , Sarcoma , Adolescente , Adulto Joven , Humanos , Niño , Imagen de Difusión por Resonancia Magnética/métodos , Estudios Retrospectivos , Rabdomiosarcoma/diagnóstico por imagen
18.
Sensors (Basel) ; 23(3)2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36772725

RESUMEN

In this paper, an experimental analysis of the quality of electrical insulating oils is performed using a combination of dielectric loss and capacitance measurement tests. The transformer oil corresponds to a fresh oil sample. The paper follows the ASTM D 924-15 standard (standard test method for dissipation factor and relative permittivity of electrical insulating liquids). Effective electrical parameters, including the tan δ of the oil, were obtained in this non-destructive test. Subsequently, a numerical method is proposed to accurately determine the effective electrical resistivity, σ, and effective electrical permittivity, ε, of an insulating mineral oil from the data obtained in the experimental analysis. These two parameters are not obtained in the ASTM standard. We used the cell method and the multi-objective non-dominated sorting in genetic algorithm II (NSGA-II) for this purpose. In this paper, a new numerical tool to accurately obtain the effective electrical parameters of transformer insulating oils is therefore provided for fault detection and diagnosis. The results show improved accuracy compared to the existing analytical equations. In addition, as the experimental data are collected in a high-voltage domain, wireless sensors are used to measure, transmit, and monitor the electrical and thermal quantities.

19.
Eur Arch Otorhinolaryngol ; 279(12): 5591-5600, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35578137

RESUMEN

PURPOSE: Current studies show that frequency tuning modification is a good marker for the detection of endolymphatic hydrops (EH) employing magnetic resonance imaging (MRI) in patients with Ménière's disease (MD). The purpose of the present study is to analyze the auditory and vestibular function with audiometric and vestibular-evoked myogenic potentials (VEMP) responses, respectively, in both the affected and unaffected ears of patients with unilateral MD using MRI as diagnostic support for the degree of EH. METHODS: We retrospectively reviewed the medical records of 76 consecutive patients with unilateral definite MD (age 55 (28-75); 39 women, 37 men). MRI was used through intravenous gadolinium administration, audiometry, and VEMPs. Functional tests were performed up to a week after the MRI. All were followed up one year after imaging utilizing clinical, auditory, and vestibular testing to rule out bilateral involvement. RESULTS: In the unaffected ear, the mean pure-tone average is normal even in cases with hydrops and, for a similar severity of hydrops is significantly lower than in the affected ear. Significant differences for the amplitude of the response at 0.5 kHz, at 1 kHz between the affected and unaffected ears were found to be lower in the affected ears. The relative amplitude ratio (1 Kz-0.5 kHz) was significantly lower in the affected ear and in the case of the oVEMP response depends on the degree of EH. The response in the unaffected ear was not modified by the presence or the degree of hydrops. CONCLUSION: In the unaffected ear, hydrops is not associated with hearing deterioration. For a similar degree of hydrops, hearing loss is significantly greater in the affected ear. The endolymphatic hydrops in the vestibule induces a frequency bias in the VEMP response only in the affected ear and not in the unaffected ear. Because of these findings we consider that hydrops does not represent an active disorder in the unaffected ear.


Asunto(s)
Hidropesía Endolinfática , Enfermedad de Meniere , Potenciales Vestibulares Miogénicos Evocados , Masculino , Humanos , Femenino , Persona de Mediana Edad , Enfermedad de Meniere/complicaciones , Enfermedad de Meniere/diagnóstico , Estudios Retrospectivos , Hidropesía Endolinfática/diagnóstico , Hidropesía Endolinfática/diagnóstico por imagen , Potenciales Vestibulares Miogénicos Evocados/fisiología , Imagen por Resonancia Magnética/métodos , Edema
20.
Rev Esp Enferm Dig ; 114(10): 628-629, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35469405

RESUMEN

Direct intestinal administration of levodopa-carbidopa gel has shown good results in selected patients with Parkinson's disease (1, 2). We want to present a complication related to the device necessary for the administration of this drug. A 58-year-old man, diagnosed with Parkinson's disease, treated for six months with levodopa-carbidopa intestinal gel, administered through a percutaneous endoscopic gastrostomy (PEG) tube with jejunal extension, presented at the emergency department for abdominal pain. The patient complained abdominal discomfort that lasted two months. It was described as pain around the umbilical area that radiated to the left lumbar region, worsened after ingestion, and did not subside with conventional analgesia.


Asunto(s)
Carbidopa , Enfermedad de Parkinson , Antiparkinsonianos , Combinación de Medicamentos , Gastrostomía/efectos adversos , Geles/uso terapéutico , Humanos , Levodopa , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/tratamiento farmacológico
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