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1.
Phys Rev Lett ; 128(13): 132502, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35426711

RESUMEN

Differential cross sections for Compton scattering from the proton have been measured at scattering angles of 55°, 90°, and 125° in the laboratory frame using quasimonoenergetic linearly (circularly) polarized photon beams with a weighted mean energy value of 83.4 MeV (81.3 MeV). These measurements were performed at the High Intensity Gamma-Ray Source facility at the Triangle Universities Nuclear Laboratory. The results are compared to previous measurements and are interpreted in the chiral effective field theory framework to extract the electromagnetic dipole polarizabilities of the proton, which gives α_{E1}^{p}=13.8±1.2_{stat}±0.1_{BSR}±0.3_{theo},ß_{M1}^{p}=0.2∓1.2_{stat}±0.1_{BSR}∓0.3_{theo} in units of 10^{-4} fm^{3}.

2.
Clin Transl Radiat Oncol ; 31: 42-49, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34622039

RESUMEN

INTRODUCTION: Few recent studies have examined patient reported outcomes (PROs) during pre- or post-operative radiation therapy (RT) for soft tissue sarcoma (STS), and none have used PROMIS. This study aims to examine PROMIS scores across peri-operative time points for patients receiving pre- or post-operative RT. METHODS: Anxiety, depression, pain interference, and physical function PROMIS domains were collected at the pre-operative (1), immediate post-operative (2), and post-treatment completion (3) timepoints for patients undergoing surgery and either pre-operative or post-operative RT. Median scores were compared between groups using the Kruskal-Wallis test. The reliable change index was used to determine minimum important change in PROMIS scores and to compare scores between timepoints. RESULTS: 95 patients were included (19 pre-operative, 76 post-operative). Both groups had significant decreases in function during treatment. Patients with wound complications were more likely to have significant increases in anxiety (36.4% vs. 8.3%; p = 0.020) and decreases in physical function (57.1% vs. 16.2%; p = 0.011) independent of RT timing. CONCLUSIONS: This study demonstrates minimum significant change thresholds to detect PROMIS changes in STS patients undergoing pre- and post-operative radiotherapy. As expected, more patients with pre-operative RT than post-operative RT had wound complications (p = 0.06), but patients with complications in both groups had worse anxiety and function at the completion of treatment compared with those that did not. The association of wound complications with worse anxiety and physical function at completion of treatment should be considered when making individualized treatment recommendations regarding the timing of RT.

3.
Clin Oncol (R Coll Radiol) ; 31(4): 232-241, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30718086

RESUMEN

AIMS: Angiosarcoma is a rare and aggressive malignancy with a poor prognosis. There is limited literature describing prognostic factors and guidelines for treatment. We aim to describe outcomes in angiosarcoma, including the impact of patient-, tumour- and treatment-related factors on prognosis. MATERIALS AND METHODS: Patients with non-metastatic angiosarcoma diagnosed between 2008 and 2017 were retrospectively reviewed. Univariable and multivariable Cox proportional hazards methods were used to evaluate factors associated with locoregional recurrence, distant failure and overall survival. The Kaplan-Meier method and log-rank statistics were used to compare outcomes among patients with and without a history of prior radiation therapy. RESULTS: The cohort included 65 patients. The median age at diagnosis was 68 years (35-93). Nineteen patients had a history of receiving prior radiation therapy at the anatomic location of their angiosarcoma. Treatment modalities included surgery (n = 19), surgery + radiation therapy (n = 12), surgery + chemotherapy (n = 8), chemotherapy + radiation therapy (n = 7) and all three modalities (n = 14). The median follow-up was 18 (2-192) months. The 2-year locoregional control, distant control and overall survival were 61.8, 63.6 and 58.9%, respectively. On multivariable analysis, a history of previous radiation therapy was associated with inferior outcomes with respect to locoregional recurrence (hazard ratio 89.67, 95% confidence interval 8.45-951.07, P < 0.001), distant failure (hazard failure 3.74, 95% confidence interval 1.57-8.91, P = 0.003) and overall survival (hazard ratio 3.89, 95% confidence interval 1.56-9.60, P = 0.003). In patients with primary angiosarcoma, the rates of locoregional control, distant control and overall survival were 72.4, 73.4 and 65.1%, respectively, compared with 31.9, 41.1 and 45.1% in patients with radiation therapy-induced angiosarcoma (P = 0.001). CONCLUSION: Angiosarcomas that arise as a result of previous radiation therapy have worse outcomes compared with primary angiosarcomas. Although selection bias and compromise of clinical care in radiation therapy-induced angiosarcoma are partially to blame, differences in genomic profiles of the tumours need to be characterised to evaluate the underlying biological differences, as this may guide future treatment management. This study adds to the existing body of literature on angiosarcoma. Results from the current study are presented alongside previously published data to further characterise outcomes and prognostic factors on this rare and aggressive malignancy.


Asunto(s)
Hemangiosarcoma/inducido químicamente , Hemangiosarcoma/radioterapia , Neoplasias Inducidas por Radiación/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Hemangiosarcoma/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Inducidas por Radiación/mortalidad , Pronóstico , Estudios Retrospectivos
4.
Neuroimage ; 59(2): 1647-56, 2012 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-21963915

RESUMEN

The human cerebellum has been implicated in the control of a wide variety of motor control parameters, such as force amplitude, movement extent, and movement velocity. These parameters often covary in both movement and isometric force production tasks, so it is difficult to resolve whether specific regions of the cerebellum relate to specific parameters. In order to address this issue, the current study used two experiments and SUIT normalization to determine whether BOLD activation in the cerebellum scales with the amplitude or rate of change of isometric force production or both. In the first experiment, subjects produced isometric pinch-grip force over a range of force amplitudes without any constraints on the rate of force development. In the second experiment, subjects varied the rate of force production, but the target force amplitude remained constant. The data demonstrate that BOLD activation in separate sub-areas of cerebellar regions lobule VI and Crus I/II scales with both force amplitude and force rate. In addition, BOLD activation in cerebellar lobule V and vermis VI was specific to force amplitude, whereas BOLD activation in lobule VIIb was specific to force rate. Overall, cerebellar activity related to force amplitude was located superior and medial, whereas activity related to force rate was inferior and lateral. These findings suggest that specific circuitry in the cerebellum may be dedicated to specific motor control parameters such as force amplitude and force rate.


Asunto(s)
Cerebelo/fisiología , Fuerza de la Mano/fisiología , Imagen por Resonancia Magnética/métodos , Contracción Muscular/fisiología , Músculo Esquelético/fisiología , Red Nerviosa/fisiología , Esfuerzo Físico/fisiología , Femenino , Humanos , Masculino , Estrés Mecánico , Adulto Joven
5.
Neurology ; 72(16): 1378-84, 2009 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-19129507

RESUMEN

BACKGROUND: In the midbrain of patients with Parkinson disease (PD), there is a selective loss of dopaminergic neurons in the ventrolateral and caudal substantia nigra (SN). In a mouse model of PD, investigators have administered 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and found that measures derived using diffusion tensor imaging (DTI) were correlated with the number of dopamine neurons lost following intoxication. METHODS: Twenty-eight subjects (14 with early stage, untreated PD and 14 age- and gender-matched controls) were studied with a high-resolution DTI protocol at 3 Tesla using an eight-channel phase array coil and parallel imaging to study specific segments of degeneration in the SN. Regions of interest were drawn in the rostral, middle, and caudal SN by two blinded and independent raters. RESULTS: Fractional anisotropy (FA) was reduced in the SN of subjects with PD compared with controls (p < 0.001). Post hoc analysis identified that reduced FA for patients with PD was greater in the caudal compared with the rostral region of interest (p < 0.00001). A receiver operator characteristic analysis in the caudal SN revealed that sensitivity and specificity were 100% for distinguishing patients with PD from healthy subjects. Findings were consistent across both raters. CONCLUSIONS: These findings provide evidence that high resolution diffusion tensor imaging in the substantia nigra distinguishes early stage, de novo patients with Parkinson disease (PD) from healthy individuals on a patient by patient basis and has the potential to serve as a noninvasive early biomarker for PD.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Degeneración Nerviosa/diagnóstico , Enfermedad de Parkinson/diagnóstico , Sustancia Negra/patología , Adulto , Anciano , Anisotropía , Biomarcadores/análisis , Diagnóstico Diferencial , Difusión , Imagen de Difusión por Resonancia Magnética/instrumentación , Progresión de la Enfermedad , Dopamina/metabolismo , Diagnóstico Precoz , Femenino , Humanos , Masculino , Persona de Mediana Edad , Degeneración Nerviosa/fisiopatología , Neuronas/metabolismo , Neuronas/patología , Enfermedad de Parkinson/fisiopatología , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Sustancia Negra/fisiopatología
7.
Pediatr Dermatol ; 18(4): 282-90, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11576399

RESUMEN

Infants wearing breathable disposable diapers experienced significantly less diaper dermatitis (DD) compared to infants wearing standard, nonbreathable disposable diapers in a series of double-blind clinical trials. Severe DD, including confirmed infection with Candida albicans, was reduced by 38-50% among infants wearing highly breathable (HB) diapers. The prevalence of DD was inversely related to the breathability of the garments. The inhibitory effect of breathable diapers on the survival of Candida was further confirmed in controlled experiments with adult volunteers. A suspension of C. albicans cells was applied to delineated sites on the volar forearm. Each site was then covered by a full-thickness patch from either an HB or a standard diaper. Survival of Candida colonies was reduced by almost two-thirds in the breathable diaper-covered sites compared to the control sites.


Asunto(s)
Candidiasis/epidemiología , Dermatitis del Pañal/epidemiología , Dermatitis del Pañal/microbiología , Cuidado del Lactante/instrumentación , Candidiasis/diagnóstico , Ensayos Clínicos Controlados como Asunto , Equipos Desechables , Método Doble Ciego , Femenino , Humanos , Incidencia , Lactante , Masculino , Pronóstico , Valores de Referencia , Factores de Riesgo , Índice de Severidad de la Enfermedad
8.
J Invest Dermatol ; 117(2): 179-87, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11511292

RESUMEN

The Comèl-Netherton syndrome is an autosomal recessive multisystemic disorder characterized by localized or generalized congenital ichthyosis, hair shaft abnormalities, immune deficiency, and markedly elevated IgE levels. Life-threatening complications during infancy include temperature and electrolyte imbalance, recurrent infections, and failure to thrive. To study the clinical presentations of the Comèl-Netherton syndrome and its molecular cause, we ascertained 19 unrelated families of various ethnic backgrounds. Results of initial linkage studies mapped the Comèl-Netherton syndrome in 12 multiplex families to a 12 cM interval on 5q32, thus confirming genetic homogeneity of Comèl-Netherton syndrome across families of different origins. The Comèl-Netherton syndrome region harbors the SPINK5 gene, which encodes a multidomain serine protease inhibitor (LEKTI) predominantly expressed in epithelial and lymphoid tissues. Recently, recessive mutations in SPINK5 were identified in several Comèl-Netherton syndrome patients from consanguineous families. We used heteroduplex analysis followed by direct DNA sequencing to screen all 33 exons and flanking intronic sequences of SPINK5 in the affected individuals of our cohort. Mutation analysis revealed 17 distinct mutations, 15 of which were novel, segregating in 14 Comèl-Netherton syndrome families. The nucleotide changes included four non-sense mutations, eight small deletions or insertions leading to frameshift, and five splice site defects, all of which are expected to result in premature terminated or altered translation of SPINK5. Almost half of the mutations clustered between exons 2 and 8, including two recurrent mutations. Genotype-phenotype correlations suggested that homozygous nucleotide changes resulting in early truncation of LEKT1 are associated with a severe phenotype. For the first time, we used molecular data to perform prenatal testing, thus demonstrating the feasibility of molecular diagnosis in the Comèl-Netherton syndrome.


Asunto(s)
Proteínas Portadoras , Eliminación de Gen , Cabello/anomalías , Eritrodermia Ictiosiforme Congénita/genética , Diagnóstico Prenatal , Inhibidores de Serina Proteinasa/genética , Adolescente , Adulto , Niño , Preescolar , Codón sin Sentido , Análisis Mutacional de ADN , Cartilla de ADN , Dermatitis Atópica/genética , Salud de la Familia , Femenino , Ligamiento Genético , Análisis Heterodúplex , Humanos , Lactante , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Fenotipo , Embarazo , Proteínas Inhibidoras de Proteinasas Secretoras , Inhibidor de Serinpeptidasas Tipo Kazal-5
9.
Pediatr Dermatol ; 15(1): 18-22, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9496797

RESUMEN

Unusual skin lesions were present at birth in four infants with Turner syndrome. The skin changes in these patients appear to have resulted either from in utero entrapment or pinching of edematous skin or from redundant skin remaining after in utero resolution of lymphedema. Distention by lymphedema is thought to cause several of the phenotypic characteristics seen in patients with Turner syndrome, including nuchal webbing and nail changes. In three of these patients the clinical appearance of the skin changes was similar to cutis verticis gyrata, marked by fixed thickened plaques in folds.


Asunto(s)
Linfedema/complicaciones , Cuero Cabelludo/anomalías , Enfermedades de la Piel/etiología , Síndrome de Turner/complicaciones , Femenino , Humanos , Lactante , Recién Nacido , Enfermedades de la Piel/patología , Neoplasias Cutáneas/etiología
13.
J Am Acad Dermatol ; 15(3): 543-5, 1986 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3760290

RESUMEN

Prevention or modification of the onset of atopic dermatitis has been difficult to document through prolonged breast feeding or delayed introduction of solid foods. Dietary management of established atopic dermatitis is not routinely indicated for the majority of patients. Dietary management of atopic dermatitis should not be continued indefinitely. Gradual reintroduction of the offending food(s) is often appropriate. The foods most commonly avoided in the management of atopic dermatitis are cow's milk, wheat, eggs, and nuts. Severe or prolonged dietary restrictions should not be instituted without full consideration of their impact on the patient's general health.


Asunto(s)
Dermatitis Atópica/dietoterapia , Factores de Edad , Lactancia Materna , Preescolar , Dermatitis Atópica/prevención & control , Hipersensibilidad a los Alimentos/dietoterapia , Humanos , Lactante , Recién Nacido , Factores de Tiempo
15.
Dermatol Clin ; 4(1): 79-87, 1986 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3720028

RESUMEN

A wide array of vascular lesions occurs in the pediatric population. The lesions vary in nature from normal physiologic phenomena to large vascular malformations with serious and sometimes life-threatening complications. Vascular lesions occur in 20 to 40 per cent of newborn infants and therefore comprise the single largest group of neoplasms in infancy and childhood. Specific entities are discussed in two major sections--hemangiomas and vascular stains.


Asunto(s)
Hemangioma Cavernoso/diagnóstico , Hemangioma/diagnóstico , Neoplasias Cutáneas/diagnóstico , Diagnóstico Diferencial , Embolización Terapéutica , Neoplasias Faciales/diagnóstico , Neoplasias Faciales/terapia , Hemangioma/terapia , Hemangioma Cavernoso/terapia , Humanos , Lactante , Recién Nacido , Terapia por Láser , Prednisona/uso terapéutico , Radioterapia , Soluciones Esclerosantes/uso terapéutico , Neoplasias Cutáneas/terapia , Síndrome
16.
Pediatr Dermatol ; 3(1): 19-30, 1985 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2999740

RESUMEN

Cutaneous histiocytosis may take two principal forms. It is either a benign proliferative process or a relentless, progressive process with a poor prognosis. In histiocytic medullary reticulosis, histiocytes demonstrate nuclear atypia and the outcome is uniformly fatal. Benign cephalic histiocytosis X causes lesions similar to those of histiocytosis X, but Langerhans' cells are absent. In congenital self-healing histiocytosis X, the Letterer-Siwe-like cutaneous infiltrate contains Langerhans' cells, but the lesions heal spontaneously without treatment. The nodular cutaneous lesions of juvenile xanthogranuloma appear in infancy and resolve without treatment; however, the higher percentage (10%) of associated ocular lesions may lead to glaucoma and blindness. In histiocytosis X, the cutaneous lesions show a marked proliferation of Langerhans' cells, with prognosis dependent on the patient's age and the extent of organ dysfunction. Patients who survive the acute form of the disease may develop diabetes insipidus, growth retardation, pulmonary fibrosis, and biliary cirrhosis. A subtle immunologic defect has been identified in patients with histiocytosis X, yet the pathogenesis of the disease is still speculative. Familial disease occurring in early infancy should be differentiated from complete or partial immunodeficiency syndromes. Guidelines for evaluating patients with cutaneous histiocytosis are reviewed.


Asunto(s)
Histiocitosis de Células de Langerhans/patología , Enfermedades Linfáticas/patología , Enfermedades de la Piel/patología , Neoplasias Cutáneas/patología , Adulto , Niño , Granuloma Eosinófilo/patología , Enfermedad Injerto contra Huésped/complicaciones , Histiocitoma Fibroso Benigno/patología , Histiocitosis de Células de Langerhans/congénito , Histiocitosis de Células de Langerhans/etiología , Histiocitosis de Células de Langerhans/genética , Histiocitosis de Células de Langerhans/inmunología , Histiocitosis de Células de Langerhans/terapia , Humanos , Lactante , Recién Nacido , Persona de Mediana Edad , Síndrome , Xantogranuloma Juvenil/patología , Xantomatosis/patología
19.
Clin Dermatol ; 3(3): 105-12, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-3880019

RESUMEN

Neonatal LE should be suspected in any infant with an erythematous or scaling dermatitis, especially if it is distributed on the head and neck or if there is a history of photosensitivity. It should also be suspected in any infant with congenital heart block. A biopsy, though helpful, is not necessary since the diagnostic abnormality is the presence of anti-Ro(SSA) antibodies in infant's serum. When the disease is diagnosed, the infant can be effectively treated with a mild topical steroid and sun avoidance, with or without sun-screens, until the age of 12 months when the autoantibodies have presumably degraded. The child then should be observed periodically through adulthood for the onset of SLE. Mothers of infants with neonatal LE need to be checked for the presence of anti-Ro antibodies and SLE, Sjögren's syndrome, or thyroiditis. The recurrence of neonatal LE in some, but not all, future pregnancies must be anticipated. As more of these infants are followed into adulthood, we will learn how often neonatal LE is a marker for adult-onset SLE.


Asunto(s)
Lupus Eritematoso Sistémico , Adolescente , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/genética , Lupus Eritematoso Sistémico/terapia , Piel/patología
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