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1.
AJNR Am J Neuroradiol ; 43(5): 675-681, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35483906

RESUMO

BACKGROUND AND PURPOSE: Imaging assessment of an immunotherapy response in glioblastoma is challenging due to overlap in the appearance of treatment-related changes with tumor progression. Our purpose was to determine whether MR imaging radiomics-based machine learning can predict progression-free survival and overall survival in patients with glioblastoma on programmed death-ligand 1 inhibition immunotherapy. MATERIALS AND METHODS: Post hoc analysis was performed of a multicenter trial on the efficacy of durvalumab in glioblastoma (n = 113). Radiomics tumor features on pretreatment and first on-treatment time point MR imaging were extracted. The random survival forest algorithm was applied to clinical and radiomics features from pretreatment and first on-treatment MR imaging from a subset of trial sites (n = 60-74) to train a model to predict long overall survival and progression-free survival and was tested externally on data from the remaining sites (n = 29-43). Model performance was assessed using the concordance index and dynamic area under the curve from different time points. RESULTS: The mean age was 55.2 (SD, 11.5) years, and 69% of patients were male. Pretreatment MR imaging features had a poor predictive value for overall survival and progression-free survival (concordance index = 0.472-0.524). First on-treatment MR imaging features had high predictive value for overall survival (concordance index = 0.692-0.750) and progression-free survival (concordance index = 0.680-0.715). CONCLUSIONS: A radiomics-based machine learning model from first on-treatment MR imaging predicts survival in patients with glioblastoma on programmed death-ligand 1 inhibition immunotherapy.


Assuntos
Glioblastoma , Antígeno B7-H1 , Feminino , Glioblastoma/diagnóstico por imagem , Glioblastoma/tratamento farmacológico , Humanos , Imunoterapia , Aprendizado de Máquina , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
2.
Osteoarthritis Cartilage ; 18 Suppl 1: S1-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20399900

RESUMO

OBJECTIVE AND METHODS: To evaluate the immune-modulator effect of chondroitin sulfate (CS) by means of the review of the literature. RESULTS: Inflammatory reactions are primarily originated by infectious agents, immune reactions and by sterile tissue lesions that activate membrane receptors by means of pathogen-associated molecular patterns, tissue breakdown products and cytokines. The activation of membrane receptors triggers the phosphorylation of mitogen activated protein kinases and of the nuclear factor kappaB (NF-kappaB). The binding of NF-kappaB to the promoter of target genes enhances the expression of pro-inflammatory cytokines, inducible nitric oxide synthase, cyclooxygenase 2, phospholipase A2, and matrix metalloproteases, proteins that contribute to tissue damage and to the inflammatory reaction. The activation of NF-kappaB has a key role in the immune homeostasis and the inflammatory response and therefore, in the pathogenesis of numerous diseases. Chondroitin sulfate (CS) is able to diminish NF-kappaB activation and nuclear translocation in chondrocytes and synovial membrane, effects that may explain the benefits of CS in osteoarthritis. In addition, systemic CS reduces NF-kappaB nuclear translocation in macrophages and hepatocytes, raising the hypothesis that CS might be of benefit to treat other diseases with a strong inflammatory component. There is preliminary evidence in humans that CS improves moderate to severe psoriasis. Moreover, experimental and clinical data suggest that CS might be a useful therapeutic agent in diseases such as inflammatory bowel diseases, atherosclerosis, Parkinson's and Alzheimer's diseases, multiple sclerosis, amyotrophic lateral sclerosis, rheumatoid arthritis and systemic lupus erythematosus. DISCUSSION: These results urge for double blinded placebo-controlled trials to confirm the utility of CS in diseases with immune and inflammatory components.


Assuntos
Anti-Inflamatórios/uso terapêutico , Sulfatos de Condroitina/uso terapêutico , Inflamação/tratamento farmacológico , Aterosclerose/tratamento farmacológico , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Osteoartrite/tratamento farmacológico , Psoríase/tratamento farmacológico
3.
Opt Express ; 17(4): 2255-63, 2009 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-19219129

RESUMO

This work is related to the development of phase-sensitive methodologies in Surface Plasmon Resonance (SPR) biosensing. We take advantage of a specific angular dependence of phase of light, reflected under SPR geometry, on parameters of the SPR-supporting metal, and propose a polarimetry-based methodology to easily determine the optimal calibration zero point, corresponding to the maximal phase sensitivity. The proposed methodology can significantly facilitate the calibration of the system in field and multi-channel sensing, broaden the dynamic range, as well as contribute to the development of feedback loops.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Desenho Assistido por Computador , Metais/química , Ressonância de Plasmônio de Superfície/instrumentação , Ressonância de Plasmônio de Superfície/métodos , Técnicas Biossensoriais/normas , Calibragem , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ressonância de Plasmônio de Superfície/normas
4.
Phys Med Biol ; 60(14): 5471-96, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26119045

RESUMO

This study aims at developing a joint FDG-PET and MRI texture-based model for the early evaluation of lung metastasis risk in soft-tissue sarcomas (STSs). We investigate if the creation of new composite textures from the combination of FDG-PET and MR imaging information could better identify aggressive tumours. Towards this goal, a cohort of 51 patients with histologically proven STSs of the extremities was retrospectively evaluated. All patients had pre-treatment FDG-PET and MRI scans comprised of T1-weighted and T2-weighted fat-suppression sequences (T2FS). Nine non-texture features (SUV metrics and shape features) and forty-one texture features were extracted from the tumour region of separate (FDG-PET, T1 and T2FS) and fused (FDG-PET/T1 and FDG-PET/T2FS) scans. Volume fusion of the FDG-PET and MRI scans was implemented using the wavelet transform. The influence of six different extraction parameters on the predictive value of textures was investigated. The incorporation of features into multivariable models was performed using logistic regression. The multivariable modeling strategy involved imbalance-adjusted bootstrap resampling in the following four steps leading to final prediction model construction: (1) feature set reduction; (2) feature selection; (3) prediction performance estimation; and (4) computation of model coefficients. Univariate analysis showed that the isotropic voxel size at which texture features were extracted had the most impact on predictive value. In multivariable analysis, texture features extracted from fused scans significantly outperformed those from separate scans in terms of lung metastases prediction estimates. The best performance was obtained using a combination of four texture features extracted from FDG-PET/T1 and FDG-PET/T2FS scans. This model reached an area under the receiver-operating characteristic curve of 0.984 ± 0.002, a sensitivity of 0.955 ± 0.006, and a specificity of 0.926 ± 0.004 in bootstrapping evaluations. Ultimately, lung metastasis risk assessment at diagnosis of STSs could improve patient outcomes by allowing better treatment adaptation.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Sarcoma/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Extremidades/diagnóstico por imagem , Extremidades/patologia , Feminino , Fluordesoxiglucose F18 , Humanos , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Sarcoma/patologia
5.
Med Phys ; 39(6Part7): 3678, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28519785

RESUMO

PURPOSE: To present a novel joint segmentation/registration for multimodality image-guided and adaptive radiotherapy. A major challenge to this framework is the sensitivity of many segmentation or registration algorithms to noise. Presented is a level set active contour based on the Jensen-Renyi (JR) divergence to achieve improved noise robustness in a multi-modality imaging space. METHODS: To present a novel joint segmentation/registration for multimodality image-guided and adaptive radiotherapy. A major challenge to this framework is the sensitivity of many segmentation or registration algorithms to noise. Presented is a level set active contour based on the Jensen-Renyi (JR) divergence to achieve improved noise robustness in a multi-modality imaging space. RESULTS: It was found that JR divergence when used for segmentation has an improved robustness to noise compared to using mutual information, or other entropy-based metrics. The MI metric failed at around 2/3 the noise power than the JR divergence. CONCLUSIONS: The JR divergence metric is useful for the task of joint segmentation/registration of multimodality images and shows improved results compared entropy based metric. The algorithm can be easily modified to incorporate non-intensity based images, which would allow applications into multi-modality and texture analysis.

6.
Med Phys ; 39(6Part3): 3615, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28517427

RESUMO

PURPOSE: To investigate the combination of PET/MR image features for the early prediction of tumor metastases to the lungs in soft-tissue sarcoma (STS) cancer. METHODS: A dataset of 24 patients with histologically proven STS was used in this study. All patients underwent pre-treatment FDG-PET and MR scans, which comprised of T1 and T2-fat suppression weighted (T2FS) sequences. The patients had a median follow-up period of 36 months (range: 6-69 months). Eight patients developed metastases to the lungs.Tumors were contoured on the T2FS scans by an expert physician. Fusion of the co-registered FDG-PET/MR scans was performed using a wavelet transform technique. A SUV feature (SUVmax) from the FDG-PET scans and 6 texture features from the co-occurrence matrix of the fused scans were extracted from the tumor region and correlation with the clinical endpoint of metastases to the lungs was investigated. Statistical analysis was performed using Spearman's rank correlation (rs) and multivariable logistic regression. RESULTS: The highest univariate prediction was found on FDG-PET/T2FS fused scans analyzed using the texture features "Sum-Mean" and "Variance". These two fused scan-texture feature combinations reached rs = -0.6838 (p = 0.0003). In comparison, SUVmax reached rs = -0.6257 (p = 0.0011). The highest multivariate prediction was found with the following 3- parameter model: -3.15*SUVmax - 5.37*FDG-PET/T2FS-Sum-Mean + 0.57*FDG-PET/T1-Variance. This model reached rs = 0.7977 (p = 0.000005). CONCLUSIONS: This work indicates the potential of PET/MR texture features of tumors as complementary metrics to existing prognostic factors. Substantial improvement in terms of prediction of metastases to the lungs in STS cancer was found with the combination of texture features from fused FDG-PET/MR scans. Potentially, this could improve patients' outcomes by allowing better adaptation of treatments. Future work will involve evaluation of the robustness of the proposed method and validation on a larger set of patients.

7.
Can Assoc Radiol J ; 39(3): 204-8, 1988 Sep.
Artigo em Francês | MEDLINE | ID: mdl-2971055

RESUMO

We describe a large family of whom twelve members were shown to have a benign bone dysplasia known as "doughnut lesions of the skull". Its clinical features are pathological fractures and cranial lumps; its radiological features comprise doughnut cranial lesions, double cortical lines of the vertebral bodies ("bone in bone"), squaring of the metatarsal and metacarpal bones, osteopenia, and tubulation defects of the diaphyses of the long bones. We believe the disease to be transmitted as an autosomal dominant trait.


Assuntos
Doenças do Desenvolvimento Ósseo/genética , Genes Dominantes , Crânio/diagnóstico por imagem , Adolescente , Adulto , Doenças do Desenvolvimento Ósseo/diagnóstico por imagem , Feminino , Fraturas Espontâneas/diagnóstico por imagem , Fraturas Espontâneas/genética , Humanos , Masculino , Linhagem , Radiografia
8.
Am Rev Respir Dis ; 115(5): 867-71, 1977 May.
Artigo em Inglês | MEDLINE | ID: mdl-857720

RESUMO

Progressively severe sneezing, rhinorrhea, cough, wheezing, and dyspnea developed in a spray-painter, apparently in relation to exposure to a particular spray paint. A monitoring of exposure at work revealed the development of symptoms and a decrease in peak flow rates. Subsequent challenges in the laboratory performed under conditions resembling occupational exposure resulted in dual asthmatic responses on exposure to the whole paint (98 per cent methyl methacrylate emulsion and 2 per cent dimethyl ethanolamine solution) and to dimethyl ethanolamine solution (2 per cent) alone. Water, methyl methacrylate emulsion, and 1,4 dioxane (0.6 per cent) used as a thinner in the dimethyl ethanolamine did not produce a response in the airways. Allergy skin tests with dimethyl ethanolamine and a mixture of dimethyl ethanolamine and human serum albumin were negative. To our knowledge, this is the first report of asthma and/or rhinitis induced specifically by dimethyl ethanolamine. The mechanism of the specific reactivity is not known.


Assuntos
Asma/induzido quimicamente , Etanolaminas/efeitos adversos , Pintura/efeitos adversos , Adulto , Humanos , Masculino , Rinite/induzido quimicamente
9.
Cancer ; 37(2): 693-6, 1976 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1082794

RESUMO

Passive immunotherapy was attempted in a patient with mast cell leukemia using antibody against IgE. The results of both in vitro and in vivo studies indicate that although receptor sites for IgE were retained by the malignant mast cell, a secretory defect was present characterized by the spontaneous release of histamine and an impaired secretory response to anti-IgE antibody. Anti-IgE antibody selectively and reproducibly reduced the number of circulating mast cells probably by facilitating their permanent uptake by the reticuloendothelial system. Tolerance was not achieved with high dose deaggregated sheep IgG, nor were we able to confirm the effectivity of immunochemotherapy based on linking chlorambucil to antibody directed against the tumor-associated "antigen" IgE.


Assuntos
Anticorpos Anti-Idiotípicos , Imunoglobulina E , Imunoterapia , Leucemia/terapia , Mastócitos , Animais , Anticorpos Anti-Idiotípicos/administração & dosagem , Sítios de Ligação de Anticorpos , Clorambucila/uso terapêutico , Humanos , Soros Imunes/análise , Imunoglobulina G/administração & dosagem , Imunoglobulina G/isolamento & purificação , Masculino , Mastócitos/imunologia , Mastócitos/metabolismo , Pessoa de Meia-Idade , Ovinos/imunologia
10.
Phys Rev C Nucl Phys ; 35(4): 1583-1585, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9953939
11.
Phys Rev C Nucl Phys ; 39(3): 1066-1075, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9955298
12.
Phys Rev C Nucl Phys ; 35(1): 320-323, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9953764
15.
Phys Rev A ; 45(8): 5512-5523, 1992 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9907649
16.
Phys Rev A ; 42(3): 1027-1032, 1990 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9904125
18.
Phys Rev A ; 43(2): 1118-1121, 1991 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9905132
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