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1.
Sci Rep ; 12(1): 15462, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104424

RESUMO

Accurate brain meningioma segmentation and volumetric assessment are critical for serial patient follow-up, surgical planning and monitoring response to treatment. Current gold standard of manual labeling is a time-consuming process, subject to inter-user variability. Fully-automated algorithms for meningioma segmentation have the potential to bring volumetric analysis into clinical and research workflows by increasing accuracy and efficiency, reducing inter-user variability and saving time. Previous research has focused solely on segmentation tasks without assessment of impact and usability of deep learning solutions in clinical practice. Herein, we demonstrate a three-dimensional convolutional neural network (3D-CNN) that performs expert-level, automated meningioma segmentation and volume estimation on MRI scans. A 3D-CNN was initially trained by segmenting entire brain volumes using a dataset of 10,099 healthy brain MRIs. Using transfer learning, the network was then specifically trained on meningioma segmentation using 806 expert-labeled MRIs. The final model achieved a median performance of 88.2% reaching the spectrum of current inter-expert variability (82.6-91.6%). We demonstrate in a simulated clinical scenario that a deep learning approach to meningioma segmentation is feasible, highly accurate and has the potential to improve current clinical practice.


Assuntos
Aprendizado Profundo , Neoplasias Meníngeas , Meningioma , Encéfalo/diagnóstico por imagem , Humanos , Neoplasias Meníngeas/diagnóstico por imagem , Meningioma/diagnóstico por imagem , Redes Neurais de Computação
2.
Semin Neurol ; 41(3): 227-238, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34010971

RESUMO

Multiple diverse pathologies result in the clinical presentation of myelopathy. The preferred way to image the spinal cord depends on clinical history, anatomic site of interest, and patient issues limiting certain imaging modalities. This radiology-focused article discusses pertinent physiological considerations, reviews basic and newer imaging techniques, and examines several distinct disease entities in order to highlight the key role of imaging in the work-up of myelopathy.


Assuntos
Imageamento por Ressonância Magnética , Doenças da Medula Espinal , Humanos , Medula Espinal , Doenças da Medula Espinal/diagnóstico por imagem
3.
Pediatr Transplant ; 19(2): 219-28, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25523718

RESUMO

Children who have undergone SOT mount a lower immune response after vaccination with TIV compared to healthy controls. HD or SD TIV in pediatric SOT was given to subjects 3-17 yr and at least six months post-transplant. Subjects were randomized 2:1 to receive either the HD (60 µg) or the SD (15 µg) TIV. Local and systemic reactions were solicited after each vaccination, and immune responses were measured before and after each vaccination. Thirty-eight subjects were enrolled. Mean age was 11.25 yr; 68% male, 45% renal, 26% heart, 21% liver, 5% lung, and 5% intestinal. Twenty-three subjects were given HD and 15 SD TIV. The median time since transplant receipt was 2.2 yr. No severe AEs or rejection was attributed to vaccination. The HD group reported more tenderness and local reactions, fatigue, and body ache when compared to the SD cohort, but these were considered mild and resolved within three days. Subjects in the HD group demonstrated a higher percentage of four-fold titer rise to H3N2 compared to the SD group. HD influenza vaccine was well tolerated and may have increased immunogenicity. A phase 2 trial is needed to confirm.


Assuntos
Vacinas contra Influenza/uso terapêutico , Influenza Humana/prevenção & controle , Transplante de Órgãos , Transplantados , Vacinação , Adolescente , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Vírus da Influenza A Subtipo H3N2 , Vacinas contra Influenza/efeitos adversos , Masculino , Segurança do Paciente , Estudos Prospectivos , Tamanho da Amostra , Resultado do Tratamento , Vacinação/efeitos adversos
4.
Pediatr Blood Cancer ; 61(5): 815-20, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24249544

RESUMO

BACKGROUND: Although children with acute lymphoblastic leukemia (ALL) mount immune responses after vaccination with the trivalent influenza vaccine (TIV), these responses are lower compared to controls. Recently, a high dose (HD) TIV was found to increase the level of antibody response in elderly patients compared to the standard dose (SD) TIV. We hypothesized that the HD TIV would be well-tolerated and more immunogenic compared to the SD TIV in pediatric subjects with ALL. PROCEDURE: This was a randomized, double-blind, phase I safety trial comparing the HD to the SD TIV in children with ALL. Our secondary objective was immunogenicity. Subjects were randomized 2:1 to receive either the HD (60 µg) or the SD (15 µg) TIV. Local and systemic reactions were solicited, hemagglutinin inhibition titers to influenza virus antigens were measured, and monitoring labs were collected prior to and/or after each vaccination. RESULTS: Fifty subjects were enrolled (34 HD, 16 SD). Mean age was 8.5 years; 63% were male, and 80% were in maintenance therapy. There were no significant differences reported in local or systemic symptoms. No severe adverse events were attributed to vaccination. No significant differences between the HD and SD TIV groups were noted for immune responses. CONCLUSIONS: No differences were noted between the HD and SD TIV groups for solicited systemic and local reactions. Since this study was not powered for immunogenicity, a phase II trial is needed to determine the immunogenicity of HD versus SD TIV in the pediatric ALL population.


Assuntos
Vírus da Influenza A/imunologia , Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Leucemia-Linfoma Linfoblástico de Células Precursoras/prevenção & controle , Vacinas de Produtos Inativados/administração & dosagem , Adolescente , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Método Duplo-Cego , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Seguimentos , Testes de Inibição da Hemaglutinação , Humanos , Vacinas contra Influenza/imunologia , Influenza Humana/imunologia , Influenza Humana/virologia , Injeções Intramusculares , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/virologia , Prognóstico , Fatores de Risco , Vacinação , Vacinas de Produtos Inativados/imunologia
5.
J Pediatr ; 153(3): 327-32, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18534242

RESUMO

OBJECTIVES: To evaluate the safety and immunogenicity of an additional birth dose of diphtheria, tetanus, and acellular pertussis vaccine (DTaP). STUDY DESIGN: Fifty infants between 2 to 14 days of age were randomly assigned to receive either DTaP and hepatitis B vaccines (experimental) or hepatitis B alone (control) at birth. At 2, 4, 6, and 17 months of age, DTaP and routine vaccines were administered to both groups. Safety data were collected after each dose, and sera were obtained at birth, 6, 7, 17, and 18 months. Immune responses to pertussis toxin, filamentous hemagglutinin, pertactin, and fimbriae were measured by enzyme-linked immunosorbent assay; responses to other vaccines were assessed. RESULTS: No differences were seen between the 2 groups in either local or systemic reactions; all vaccines were well tolerated. Compared with the control group, infants in the experimental group demonstrated significantly lower geometric mean antibody concentrations for pertussis toxin and pertactin 6, 7, and 18 months, for fimbrae at 6, 7, 17, and 18 months, and for FHA at 18 months, and lower geometric mean antibody concentrations for diphtheria at 7 months. Immune responses to all other vaccine antigens were comparable. CONCLUSION: Administration of an additional dose of DTaP at birth was safe but was associated with a significantly lower response to diphtheria and 3 of 4 pertussis antigens compared with controls.


Assuntos
Vacina contra Difteria, Tétano e Coqueluche/administração & dosagem , Vacinas Anti-Haemophilus/administração & dosagem , Imunidade/fisiologia , Toxoide Tetânico/administração & dosagem , Difteria/prevenção & controle , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Feminino , Seguimentos , Infecções por Haemophilus/prevenção & controle , Humanos , Imunidade/efeitos dos fármacos , Lactente , Recém-Nascido , Masculino , Projetos Piloto , Prognóstico , Estudos Prospectivos , Fatores de Risco , Tétano/prevenção & controle , Vacinas Conjugadas , Coqueluche/prevenção & controle
6.
Vaccine ; 25(42): 7372-8, 2007 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-17868959

RESUMO

Early in the development of respiratory syncytial virus (RSV) vaccines severe disease occurred in children after receipt of formalin-inactivated RSV vaccine. Continuing efforts to develop an appropriately attenuated and immunogenic live RSV vaccine have given opportunities to assure that live vaccines are safe through surveillance of children after vaccination. In the present study, the rate of RSV-associated upper respiratory tract illness in 388 children was lower in RSV vaccinated children than in controls (14% versus 20% in a 6-24 month old group and 16% versus 25% in infants). Additionally, there was no evidence that vaccination predisposed to more severe lower respiratory tract illness. Thus infection with a series of live attenuated RSV vaccines did not result in enhanced disease upon infection with wild type RSV. The impact of RSV during this surveillance will inform the design of future efficacy studies with RSV vaccines.


Assuntos
Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vacinas contra Vírus Sincicial Respiratório/farmacologia , Vírus Sincicial Respiratório Humano/imunologia , Anticorpos Antivirais/sangue , Estudos de Casos e Controles , Humanos , Lactente , Infecções por Vírus Respiratório Sincicial/imunologia , Vacinas contra Vírus Sincicial Respiratório/efeitos adversos , Vacinas contra Vírus Sincicial Respiratório/imunologia , Segurança , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/farmacologia
7.
J Infect Dis ; 193(4): 573-81, 2006 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-16425137

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) is targeted for vaccine development, because it causes severe respiratory tract illness in the elderly, young children, and infants. A primary strategy has been to derive live attenuated viruses for use in intranasally administered vaccines that will induce a protective immune response. In the present study, the NS2 gene, whose encoded protein antagonizes the host's interferon- alpha / beta response, was deleted from RSV vaccine candidates by use of reverse genetics. METHODS: Three NS2 gene-deleted RSV vaccine candidates were studied: rA2cp Delta NS2, rA2cp248/404 Delta NS2, and rA2cp530/1009 Delta NS2. rA2cp Delta NS2, which had the fewest attenuating mutations, was evaluated in adults and RSV-seropositive children. rA2cp248/404 Delta NS2 and rA2cp530/1009 Delta NS2 were evaluated in adults and RSV-seropositive and RSV-seronegative children. RESULTS: At a high dose (10(7.0) pfu), rA2cp Delta NS2 was not shed by adults, and only 13% of them had an immune response. The other vaccine candidates, rA2cp248/404 Delta NS2 and rA2cp530/1009 Delta NS2, had greatly decreased infectivity in RSV-seronegative children, compared with that of their immediate parent strains, which possess an intact NS2 gene. CONCLUSIONS: Deletion of the NS2 gene attenuates RSV in subjects of all ages studied. This validates the strategy of developing live respiratory tract virus vaccines in which the virus's ability to inhibit the human innate immune system is blocked. rA2cp248/404 Delta NS2 should be studied in children at a higher input titer, because it was more infectious and immunogenic than was rA2cp530/1009 Delta NS2.


Assuntos
Interferons/agonistas , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/patogenicidade , Proteínas não Estruturais Virais/toxicidade , Virulência/fisiologia , Adulto , Criança , Pré-Escolar , Humanos , Vírus Sincicial Respiratório Humano/química , Vacinação , Eliminação de Partículas Virais
8.
J Pediatr ; 141(1): 135-40, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12091866

RESUMO

Complex regional pain syndromes (CRPS; type 1, reflex sympathetic dystrophy, and type 2, causalgia) involve persistent pain, allodynia, and vasomotor signs. We conducted a prospective, randomized, single-blind trial of physical therapy (PT) and cognitive-behavioral treatment for children and adolescents with CRPS. Children 8 to 17 years of age (n = 28) were randomly assigned to either group A (PT once per week for 6 weeks) or group B (PT 3 times per week for 6 weeks). Both groups received 6 sessions of cognitive-behavioral treatment. Assessments of pain and function were repeated at two follow-up time periods. Outcomes were compared at the three time points through the use of parametric or nonparametric analysis of variance and post hoc tests. All five measures of pain and function improved significantly in both groups after treatment, with sustained benefit evident in the majority of patients at long-term follow-up. Recurrent episodes were reported in 50% of patients, and 10 patients eventually received sympathetic blockade. Most children with CRPS showed reduced pain and improved function with a noninvasive rehabilitative treatment approach. Long-term functional outcomes were also very good.


Assuntos
Terapia Cognitivo-Comportamental , Síndromes da Dor Regional Complexa/reabilitação , Modalidades de Fisioterapia , Adolescente , Criança , Síndromes da Dor Regional Complexa/psicologia , Feminino , Humanos , Masculino , Estudos Prospectivos , Estatísticas não Paramétricas
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