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1.
Bioorg Med Chem ; 55: 116600, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34999526

RESUMO

Glioma is the most common primary intracranial tumor without effective treatment. Positron emission tomography tracers labeled with 68Ga targeting fibroblast activation protein (FAP) have shown favorable characteristics in the diagnosis of glioma. However, to the best of our knowledge, FAP-targeted endoradiotherapy has never been explored in glioma. Hence, in this study, we investigated the therapeutic effect of 211At-labeled fibroblast activation protein inhibitor (FAPI) for glioma in vitro and in vivo. By astatodestannylation reaction, we prepared 211At-FAPI-04 with a radiochemical yield of 45 ± 6.7% and radiochemical purity of 98%. With good stability in vitro, 211At-FAPI-04 showed fast and specific binding to FAP-positive U87MG cells, and could significantly reduce the cell viability, arrested cell cycle at G2/M phase and suppressed cell proliferative efficacy. Biodistribution studies revealed that 6-fold higher accumulation in tumor sites was achieved by intratumoral injection in comparison with intravenous injection. In U87MG xenografts, 211At-FAPI-04 obviously suppressed the tumor growth and prolonged the median survival in a dose-dependent manner without obvious toxicity to normal organs. In addition, reduced proliferation and increased apoptosis were also observed after 211At-FAPI-04 treatment. All these results suggest that targeted alpha-particle therapy (TAT) mediated by 211At-FAPI-04 can provide an effective and promising strategy for the treatment of glioma.

2.
Mol Pharm ; 18(11): 4179-4187, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34591481

RESUMO

As an excellent target for cancer theranostics, fibroblast activation protein (FAP) has become an attractive focus in cancer research. A class of FAP inhibitors (FAPIs) with a N-(4-quinolinoyl)-Gly-(2-cyanopyrrolidine) scaffold were developed, which displayed nanomolar affinity and high selectivity. Compared with 90Y, 177Lu, 225Ac, and 188Re, 211At seems to be more favored as a therapeutic candidate for FAPI tracers which have fast washout and short retention in tumor sites. Thus, the current study reported the synthesis of two FAPI precursors for 211At and 131I labeling and the preliminary evaluation of 131I-labeled FAPI analogues for cancer theranostics. FAPI variants with stannyl precursors were successfully synthesized and labeled with 131I using a radioiododestannylation reaction. Two radioactive tracers were obtained with high radiochemical purity over 99% and good radiochemical yields of 58.2 ± 1.78 and 59.5 ± 4.44% for 131I-FAPI-02 and 131I-FAPI-04, respectively. Both tracers showed high specific binding to U87MG cells in comparison with little binding to MCF-7 cells. Compared to 131I-FAPI-02, 131I-FAPI-04 exhibited higher affinity, more intracellular uptake, and longer retention time in vitro. Biodistribution studies revealed that both tracers were mainly excreted through the kidneys as well as the hepatobiliary pathway due to their high lipophilicity. In addition, higher accumulation, longer dwell time, and increased tumor-to-organ ratios were achieved by 131I-FAPI-04, which was clearly demonstrated by SPECT/CT imaging. Furthermore, intratumor injection of 131I-FAPI-04 significantly suppressed the tumor growth in U87MG xenograft mice without significant toxicity observed. The above results implied that FAP-targeted alpha endoradiotherapy (specific to 211At) should be used to treat tumors in the near future, considering the chemical similarity between iodine and astatine can ensure the labeling of the latter onto the designed FAPIs.


Assuntos
Astato/administração & dosagem , Proteínas de Membrana/antagonistas & inibidores , Neoplasias/terapia , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos , Animais , Linhagem Celular Tumoral , Endopeptidases , Humanos , Radioisótopos do Iodo , Camundongos , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Traçadores Radioativos , Nanomedicina Teranóstica/métodos , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
3.
PLoS Comput Biol ; 15(1): e1006633, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30640910

RESUMO

The mental contents of perception and imagery are thought to be encoded in hierarchical representations in the brain, but previous attempts to visualize perceptual contents have failed to capitalize on multiple levels of the hierarchy, leaving it challenging to reconstruct internal imagery. Recent work showed that visual cortical activity measured by functional magnetic resonance imaging (fMRI) can be decoded (translated) into the hierarchical features of a pre-trained deep neural network (DNN) for the same input image, providing a way to make use of the information from hierarchical visual features. Here, we present a novel image reconstruction method, in which the pixel values of an image are optimized to make its DNN features similar to those decoded from human brain activity at multiple layers. We found that our method was able to reliably produce reconstructions that resembled the viewed natural images. A natural image prior introduced by a deep generator neural network effectively rendered semantically meaningful details to the reconstructions. Human judgment of the reconstructions supported the effectiveness of combining multiple DNN layers to enhance the visual quality of generated images. While our model was solely trained with natural images, it successfully generalized to artificial shapes, indicating that our model was not simply matching to exemplars. The same analysis applied to mental imagery demonstrated rudimentary reconstructions of the subjective content. Our results suggest that our method can effectively combine hierarchical neural representations to reconstruct perceptual and subjective images, providing a new window into the internal contents of the brain.


Assuntos
Encéfalo/fisiologia , Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Imaginação/fisiologia , Imageamento por Ressonância Magnética/métodos , Processamento de Sinais Assistido por Computador , Adulto , Algoritmos , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
4.
Nanomedicine ; 29: 102248, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32574686

RESUMO

Melanin is a group of natural pigments found in living organism. It can be used for positron emission tomography (PET) imaging due to its inherent chelating ability to radioactive cupric ion. This study was to prepare 64Cu-labeled PEGylated melanin nanoparticles (64Cu-PEG-MNPs), and to further take advantage of the enhanced permeability and retention (EPR) effect of radiolabeled nanoparticles to realize the integration of tumor diagnosis and treatment. We successfully synthesized PEG-MNPs. Saline and serum stability experiments demonstrated good stability. PET/CT showed high tumor aggregation. Moreover, 64Cu-PEG-MNPs resulted in a therapeutic effect on the A431 tumor-bearing mice in the treatment group. The pathological results further confirmed that the therapeutic doses of 64Cu-PEG-MNPs cause pathological changes of tumor tissues while showing minimal toxicity to normal tissues. Our data successfully demonstrate the good imaging performance of 64Cu-PEG-MNPs on A431 tumors and further proved its therapeutic effect, highlighting a great potential in targeted radionuclide therapy.


Assuntos
Melaninas/farmacologia , Nanopartículas/química , Neoplasias/radioterapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Animais , Linhagem Celular Tumoral , Radioisótopos de Cobre/farmacologia , Humanos , Melaninas/química , Camundongos , Nanopartículas/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Small ; 15(12): e1804920, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30767425

RESUMO

Electronic eye cameras are receiving increasing interest due to their unique advantages such as wide field of view, low aberrations, and simple imaging optics compared to conventional planar focal plane arrays. However, the spectral sensing ranges of most electronic eyes are confined to the visible, which is limited by the energy gaps of the sensing materials and by fabrication obstacles. Here, a potential route leading to infrared electronic eyes is demonstrated by exploring flexible colloidal quantum dot (CQD) photovoltaic detectors. Benefitting from their tunable optical response and the ease of fabrication as solution processable materials, mercury telluride (HgTe) CQD detectors with mechanical flexibility, wide spectral sensing range, fast response, and high detectivity are demonstrated. A strategy is provided to further enhance the light absorption in flexible detectors by integrating a Fabry-Perot resonant cavity. Integrated short-wave IR detectors on flexible substrates have peak D* of 7.5 × 1010 Jones at 2.2 µm at room temperature and promise the development of infrared electronic eyes with high-resolution imaging capability. Finally, infrared images are captured with the flexible CQD detectors at varying bending conditions, showing a practical approach to sensitive infrared electronic eyes beyond the visible range.

8.
AJR Am J Roentgenol ; 210(1): 58-67, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29091006

RESUMO

OBJECTIVE: The objective of our study was to evaluate the diagnostic performance of DWI using a 5-point rank scale, lesion-to-spinal cord signal intensity ratio, which we refer to as "LSR," and apparent diffusion coefficient (ADC) for the characterization of pulmonary lesions. MATERIALS AND METHODS: After a literature search in several databases, two investigators independently selected studies, assessed methodologic quality, and extracted data. On a per-lesion basis, we pooled and compared the three parameters for malignant and benign lesions. Also, we determined pooled sensitivity and specificity with individual 95% CIs. RESULTS: In total, 31 articles involving 2368 lesions were included. The mean scores of malignant and benign lesions on the 5-point scale were 3.83 (95% CI, 3.71-3.96) and 2.36 (95% CI, 2.18-2.54), respectively. The mean LSRs of malignant and benign lesions were 1.15 (95% CI, 1.07-1.24) and 0.71 (95% CI, 0.62-0.79). The mean ADC values of malignant and benign lesions were 1.23 (95% CI, 1.21-1.24) and 1.72 (95% CI, 1.68-1.77). All three parameters differed significantly between malignant and benign lesions (p < 0.05). On the basis of these parameters, the pooled sensitivity and specificity were 0.88 (95% CI, 0.84-0.91) and 0.75 (95% CI, 0.68-0.80) for the 5-point scale, 0.80 (95% CI, 0.75-0.85) and 0.85 (95% CI, 0.76-0.92) for LSR, and 0.84 (95% CI, 0.82-0.86) and 0.84 (95% CI, 0.81-0.87) for ADC. CONCLUSION: Three DWI parameters-a visual parameter (score on a 5-point scale), semiquantitative parameter (LSR), and quantitative parameter (ADC)-can help to distinguish malignant from benign pulmonary lesions.


Assuntos
Imagem de Difusão por Ressonância Magnética , Pneumopatias/diagnóstico por imagem , Humanos , Sensibilidade e Especificidade
9.
Acta Radiol ; 59(2): 188-195, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28475024

RESUMO

Background Positron emission tomography (PET) imaging using the radiotracers 18F-fluorodeoxyglucose (FDG) or 18F-fluorothymidine (FLT) has been proposed as imaging biomarkers of cell proliferation. Purpose To explore the correlations of FDG and FLT uptake with the Ki-67 labeling index in patients with lung cancer. Material and Methods Major databases were systematically searched for all relevant literature published in English. The correlation coefficient (rho) and its 95% confidence interval (CI) of individual studies were meta-analyzed using a random-effects model. The sources of heterogeneity were explored by subgroup analyses. Results Twenty-seven articles involving 1213 patients were included in this meta-analysis, comprising 22 studies for FDG uptake/Ki-67 expression correlation and eight for FLT uptake/Ki-67 expression correlation. The pooled rho values for 18F-FDG/Ki-67 correlation and 18F-FLT/Ki-67 correlation were 0.45 (95% CI, 0.41-0.50) and 0.65 (95% CI, 0.56-0.73), respectively, which indicated a moderate correlation for the former and a significant one for the latter. Although the subgroup analyses based on study design, scanner, sample method, and Ki-67 labeling method did not significantly explain the heterogeneity, these factors were potential sources of heterogeneity. In lung cancer, the pooled SUVmax of FDG uptake was significantly higher than that of FLT uptake (7.59 versus 3.86, P < 0.05). In addition, compared to FDG, FLT showed higher specificity yet lower sensitivity for the diagnosis of pulmonary lesions. Conclusion Both 18F-FDG and 18F-FLT correlate significantly with the Ki-67 labeling index in pulmonary lesions, and the latter, with a stronger correlation, may be more reliable for assessing tumor cell proliferation in lung cancer.


Assuntos
Didesoxinucleosídeos/metabolismo , Fluordesoxiglucose F18/metabolismo , Antígeno Ki-67/análise , Neoplasias Pulmonares/diagnóstico , Tomografia por Emissão de Pósitrons , Humanos , Neoplasias Pulmonares/química , Sensibilidade e Especificidade
10.
Acta Radiol ; 59(12): 1487-1493, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29486597

RESUMO

BACKGROUND: 18F-fluorodeoxyglucose *Equal contributors. positron emission tomography/computed tomography (18F-FDG PET/CT) has proven to be a valuable imaging modality for the assessment of bone marrow condition. PURPOSE: To investigate the physiological uptake of 18F-FDG in the vertebral bone marrow in healthy adults on PET/CT imaging, and correlate the appearance with clinical factors including gender, body mass index, and age. MATERIAL AND METHODS: A total of 64 healthy individuals underwent PET/CT scan, and for each vertebral body, the mean and maximum standardized uptake value (SUVmean and SUVmax) were determined in the central slice of vertebral body on the transversal fused PET/CT image. For each individual, the FDG uptake of the four regions was obtained by averaging the SUVmean and SUVmax of the vertebrae in individual regions. RESULTS: The FDG uptake from thoracic to sacral vertebrae showed an upward trend first, then a downward trend, while that of cervical vertebrae was relatively stable. The SUVmax and SUVmean values of bone marrow in the old group (age ≥ 50 years) were significantly lower than those in the young group (age < 50 years) in all regions of the spine ( P < 0.05). FDG uptake of the whole spine showed significant negative correlation with age, and the strongest correlation was observed in lumbar spine (SUVmean: r = -0.364, P < 0.05; SUVmax: r = -0.344, P < 0.05). CONCLUSION: FDG uptake showed a tendency to increase first then decrease from thoracic to sacral vertebrae while the tendency was not obvious in cervical vertebrae. In addition, the glycolytic metabolism of all the four regions decreased with advancing age.


Assuntos
Medula Óssea/metabolismo , Fluordesoxiglucose F18/farmacocinética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos/farmacocinética , Coluna Vertebral/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Vértebras Cervicais/metabolismo , Feminino , Humanos , Vértebras Lombares/metabolismo , Masculino , Pessoa de Meia-Idade , Valores de Referência , Vértebras Torácicas/metabolismo , Adulto Jovem
11.
Eur Radiol ; 27(11): 4786-4796, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28477166

RESUMO

OBJECTIVES: The aim of this meta-analysis was to evaluate the accuracy of 18F-FDG PET/CT in predicting the pathological response to neoadjuvant chemotherapy (NAC) in breast cancer (BC) patients. METHODS: PubMed, Embase, the Cochrane Library (Central), and the Web of Science (SCI-Expanded) were systematically searched to identify pertinent studies. The methodologic quality of the included studies was assessed by the Quality Assessment of Diagnostic Accuracy Studies-2. The Spearman correlation coefficient was used to explore the existence of a threshold effect. Heterogeneity was assessed by the likelihood ratio I 2 index. RESULTS: The pooled values calculated with a mixed-effects model for the sensitivity, specificity and diagnostic odds ratio with 95% confidence intervals were 81.9% (76.0-86.6%), 79.3% (72.1-85.1%) and 17.35 (10.98-27.42), respectively. CONCLUSIONS: 18F-FDG PET/CT has a moderate accuracy in predicting the pathological response during the early process of NAC in breast cancer patients. To increase the role of 18F-FDG PET/CT in monitoring the therapy response, future prospective studies are needed to explore how chemotherapy regimens and different subtypes affect the levels of glucose metabolism. KEY POINTS: • This meta-analysis assesses the role of PET/CT in breast cancer during NAC. • Pathological responses were based on both primary tumour and lymph node. • 18 F-FDG PET/CT has a moderate accuracy in predicting the pathological response.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Feminino , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Terapia Neoadjuvante , Razão de Chances , Sensibilidade e Especificidade
12.
Eur Radiol ; 26(2): 556-66, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26003791

RESUMO

OBJECTIVES: The potential performance of apparent diffusion coefficient (ADC) values for distinguishing malignant and benign pulmonary lesions, further characterizing the subtype of lung cancer was assessed. METHODS: PubMed, EMBASE, Cochrane Library, EBSCO, and three Chinese databases were searched to identify eligible studies on diffusion-weighted imaging (DWI) of focal pulmonary lesions. ADC values of malignant and benign lesions were extracted by lesion type and statistically pooled based on a linear mixed model. Further analysis for subtype of lung cancer was also performed. The methodological quality was assessed using the quality assessment of diagnostic accuracy studies tool. RESULTS: Thirty-four articles involving 2086 patients were included. Malignant pulmonary lesions have significantly lower ADC values than benign lesions [1.21 (95% CI, 1.19-1.22) mm(2)/s vs. 1.76 (95% CI, 1.72-1.80) mm(2)/s; P < 0.05]. There is a significant difference between ADC values of small cell lung cancer and non-small cell lung cancer (P < 0.05), while the differences were not significant among histological subtypes of lung cancer. The methodological quality was relatively high, and the data points from Begg's test indicated that there was probably no obvious publication bias. CONCLUSIONS: The ADC value is helpful for distinguishing malignant and benign pulmonary lesions and provides a promising method for differentiation of SCLC from NSCLC. KEY POINTS: • This meta-analysis assesses the role of DWI in pulmonary lesions. • Differentiation and classification subtype of lung cancer is essential for treatment decision-making. • ADC values can help distinguish between malignant and benign lesions. • ADC values might help characterize the subtype of lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Pulmonares/patologia , Carcinoma de Pequenas Células do Pulmão/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
13.
AJR Am J Roentgenol ; 206(2): 283-90, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26587799

RESUMO

OBJECTIVE: The purpose of this study is to assess the diagnostic performance of DWI in the N stage assessment of patients with lung cancer. MATERIALS AND METHODS: The PubMed, EMBASE, Cochrane Library, Web of Science, and EBSCO English-language databases and two Chinese-language databases were searched for eligible studies. On the basis of the data extracted from included studies, we determined the pooled sensitivity and specificity, calculated the positive and negative likelihood ratios, and constructed summary ROC curves. In addition, we also performed threshold effect analysis, metaregression analysis, subgroup analysis, and publication bias analysis to explain the source of heterogeneity. RESULTS: A total of 18 articles involving 1116 patients met the inclusion criteria. On a per-patient basis, the pooled sensitivity and specificity estimates of DWI were 0.68 (95% CI, 0.63-0.73) and 0.92 (95% CI, 0.90-0.94), respectively. On a per-lesion basis, the corresponding estimates were 0.72 (95% CI, 0.69-0.75) for sensitivity and 0.96 (95% CI, 0.95-0.96) for specificity. Only the analysis method (quantitative vs qualitative) affected the diagnostic accuracy on the basis of subgroup and metaregression analysis. CONCLUSION: Current evidence suggests that DWI is beneficial in the nodal assessment of patients with lung cancer, and it is necessary to conduct high-quality prospective studies regarding the use of DWI in detecting metastatic lymph nodes of lung cancer to determine its true value.


Assuntos
Imagem de Difusão por Ressonância Magnética , Neoplasias Pulmonares/patologia , Linfonodos/patologia , Humanos , Neoplasias Pulmonares/diagnóstico , Metástase Linfática , Estadiamento de Neoplasias
14.
Acta Radiol ; 56(6): 681-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24917609

RESUMO

BACKGROUND: Lymph node staging in non-small cell lung cancer (NSCLC) is challenging and important for determining treatment policy. Conflicting results have been presented to date. PURPOSE: To evaluate the diagnostic performance of dual time-point (DTP) 18 F-FDG PET/CT compared with single time-point (STP) imaging for detecting mediastinal nodal metastases in patients with NSCLC. MATERIAL AND METHODS: The PubMed, EMBASE, EBSCO, and Web of Knowledge databases were searched for relevant articles. The pooled sensitivity, specificity, diagnostic odds ratio (DOR), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) were calculated using Meta-Disc software. Summary receiver-operating characteristic (SROC) curves were also constructed. The potential for between-study heterogeneity was explored using subgroup analyses. RESULTS: A total of eight studies involving 654 patients fulfilled the inclusion criteria. On a per-patient analysis, the pooled sensitivity and specificity with a 95% confidence interval (CI) for DTP PET/CT were 0.85 (0.78-0.91), 0.75 (0.68-0.82), and for STP imaging, they were 0.79 (0.70-0.85), 0.73 (0.65-0.79), respectively. On a per-lesion basis, the corresponding values for DTP imaging were 0.84 (0.81-0.86), 0.89 (0.87-0.91), and for STP imaging, they were 0.84 (0.80-0.86), 0.83 (0.81-0.85), respectively. CONCLUSION: DTP PET/CT performed better than STP imaging in evaluating the lymph node status of NSCLC patients and had the potential to be broadly applied in clinical practice. However, due to the small sample size and large heterogeneity, current evidence does not justify the implementation of DTP imaging in routine PET protocols for mediastinal lymph node staging of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/secundário , Fluordesoxiglucose F18 , Neoplasias Pulmonares/patologia , Imagem Multimodal , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X/métodos , Humanos , Metástase Linfática , Mediastino , Fatores de Tempo
15.
Eur J Neurosci ; 39(12): 2071-82, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24661456

RESUMO

Multivariate pattern classification analysis (MVPA) has been applied to functional magnetic resonance imaging (fMRI) data to decode brain states from spatially distributed activation patterns. Decoding upper limb movements from non-invasively recorded human brain activation is crucial for implementing a brain-machine interface that directly harnesses an individual's thoughts to control external devices or computers. The aim of this study was to decode the individual finger movements from fMRI single-trial data. Thirteen healthy human subjects participated in a visually cued delayed finger movement task, and only one slight button press was performed in each trial. Using MVPA, the decoding accuracy (DA) was computed separately for the different motor-related regions of interest. For the construction of feature vectors, the feature vectors from two successive volumes in the image series for a trial were concatenated. With these spatial-temporal feature vectors, we obtained a 63.1% average DA (84.7% for the best subject) for the contralateral primary somatosensory cortex and a 46.0% average DA (71.0% for the best subject) for the contralateral primary motor cortex; both of these values were significantly above the chance level (20%). In addition, we implemented searchlight MVPA to search for informative regions in an unbiased manner across the whole brain. Furthermore, by applying searchlight MVPA to each volume of a trial, we visually demonstrated the information for decoding, both spatially and temporally. The results suggest that the non-invasive fMRI technique may provide informative features for decoding individual finger movements and the potential of developing an fMRI-based brain-machine interface for finger movement.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Dedos/fisiologia , Imageamento por Ressonância Magnética/métodos , Atividade Motora/fisiologia , Processamento de Sinais Assistido por Computador , Adolescente , Adulto , Feminino , Humanos , Masculino , Análise Multivariada , Testes Neuropsicológicos , Estimulação Luminosa , Tempo de Reação , Máquina de Vetores de Suporte , Percepção Visual/fisiologia , Adulto Jovem
16.
Neurochem Res ; 39(7): 1355-62, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24792733

RESUMO

Nocturnal enuresis is a common developmental disorder in children; primary monosymptomatic nocturnal enuresis (PMNE) is the dominant subtype. Previous literature has suggested that the prefrontal cortex and the pons are both involved in micturition control. This study aimed to investigate the metabolic levels of the left prefrontal cortex and the pons in children with PMNE by proton magnetic resonance spectroscopy (1H-MRS). Twenty-five children with PMNE and 25 healthy children took part in our experiments. Magnetic resonance examinations were performed on a Siemens 3T Trio Tim scanner. For each subject, localized 1H-MRS was acquired from the left prefrontal cortex (mainly in brodmann area 9) and the pons with a point-resolved spectroscopy sequence with repetition time 2,000 ms, echo time 30 ms and 64 averages. The LCModel software package was used to analyze the MRS raw data, and two-sample t tests were used to determine significant differences between the two groups. The results revealed a significant reduction in metabolite to total creatine ratios of N-acetylaspartate (NAA/tCr) in the left prefrontal cortex and the pons for children with PMNE compared to healthy children. Our study suggests that metabolism is disturbed in the prefrontal cortex and the pons in children with PMNE, which may be associated with the symptoms of enuresis.


Assuntos
Ácido Aspártico/análogos & derivados , Encéfalo/metabolismo , Creatina/metabolismo , Enurese Noturna/diagnóstico , Enurese Noturna/metabolismo , Espectroscopia de Prótons por Ressonância Magnética , Adolescente , Ácido Aspártico/metabolismo , Criança , Feminino , Humanos , Masculino
17.
Skeletal Radiol ; 43(11): 1503-13, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24841276

RESUMO

Published data on the diagnosis of bone metastases of prostate cancer are conflicting and heterogeneous. We performed a comprehensive meta-analysis to compare the diagnostic performance of choline-PET/CT, MRI, bone SPECT, and bone scintigraphy (BS) in detecting bone metastases in parents with prostate cancer. Pooled sensitivity, specificity, and diagnostic odds ratios (DOR) were calculated both on a per-patient basis and on a per-lesion basis. Summary receiver operating characteristic (SROC) curves were also drawn to obtain the area under curve (AUC) and Q* value. Sixteen articles consisting of 27 studies were included in the analysis. On a per-patient basis, the pooled sensitivities by using choline PET/CT, MRI, and BS were 0.91 [95% confidence interval (CI): 0.83-0.96], 0.97 (95% CI: 0.91-0.99), 0.79 (95% CI: 0.73-0.83), respectively. The pooled specificities for detection of bone metastases using choline PET/CT, MRI, and BS, were 0.99 (95% CI: 0.93-1.00), 0.95 (95% CI: 0.90-0.97), and 0.82 (95% CI: 0.78-0.85), respectively. On a per-lesion basis, the pooled sensitivities of choline PET/CT, bone SPECT, and BS were 0.84 (95% CI: 0.81-0.87), 0.90 (95% CI: 0.86-0.93), 0.59 (95% CI: 0.55-0.63), respectively. The pooled specificities were 0.93 (95% CI: 0.89-0.96) for choline PET/CT, 0.85 (95% CI: 0.80-0.90) for bone SPECT, and 0.75 (95% CI: 0.71-0.79) for BS. This meta-analysis indicated that MRI was better than choline PET/CT and BS on a per-patient basis. On a per-lesion analysis, choline PET/CT with the highest DOR and Q* was better than bone SPECT and BS for detecting bone metastases from prostate cancer.


Assuntos
Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/secundário , Imageamento por Ressonância Magnética/estatística & dados numéricos , Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Neoplasias da Próstata/diagnóstico , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Neoplasias Ósseas/epidemiologia , Colina , Humanos , Masculino , Imagem Multimodal/estatística & dados numéricos , Variações Dependentes do Observador , Prevalência , Neoplasias da Próstata/epidemiologia , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Zhonghua Nan Ke Xue ; 20(11): 1039-42, 2014 Nov.
Artigo em Zh | MEDLINE | ID: mdl-25577843

RESUMO

Prostate cancer is the most common malignancy in the urinary system of males. The remarkable biological and clinical heterogeneity of prostate cancer poses challenges to the initial diagnosis, differential diagnosis, treatment, and prognosis of the disease. Positron emission tomography/computed tomography (PET/CT) is an ideal imaging tool for noninvasive interrogation of underlying tumor biology. Recently, there are a variety of molecular imaging paths and radiopharmaceuticals for the diagnosis and treatment of prostate cancer. This article reviews the current state and prospects of the application of PET in the diagnosis of prostate cancer.


Assuntos
Imagem Molecular/métodos , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons , Neoplasias da Próstata/diagnóstico por imagem , Humanos , Masculino , Prognóstico , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X
19.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 31(4): 881-7, 2014 Aug.
Artigo em Zh | MEDLINE | ID: mdl-25464807

RESUMO

This paper is aimed to assess the diagnostic value of MRI versus 99 Tcm-methylene diphosphonate (99 Tcm- MDP) bone scan (BS) for osseous metastases in patients with prostate cancer. The computer-based retrieval was conducted on PubMed, EMBASE, EBSCO, Web of Knowledge, the Cochrane Library and Ovid data bases to search for trials about diagnosing osseous metastases of prostate cancer with MRI and 99Tc"m-MDP BS. Selected with time acceptance and time exclusion criteria, the data quality were evaluated with QUADAS quality assessment tool and collected. We used the Meta-Disc software to conduct meta-analysis, and then calculated the pooled sensitivity, specificity and diagnostic odds ratio (DOR), drew the summary receiving operating characteristic (SROC) curve, and measured the area under curve (AUC) and Q value. Then five studies were included, involving 353 patients. The pooled sensitivity of MRI and BS was 0. 95 (95% CI 0. 90~0. 98) and 0. 67 (95% CI 0. 58~0. 75), respectively. The pooled specificity was 0. 97 (95% CI 0. 94~0. 99) and 0. 88 (95% CI 0. 83~0. 91), respectively. The pooled DOR was 402.99 (95% CI 119. 05 ~1364. 15) and 23. 85 (95% CI 1. 32~431. 48), respectively. The AUC was 0. 990 1 and 0. 624 1, respectively. The Q was 0. 958 7 and 0. 593 8. It can well be concluded that MRI is more effective than 99 Tcm-MDP BS in the diagnosis of osseous metastases in patients with prostate cancer.


Assuntos
Neoplasias Ósseas/diagnóstico , Imageamento por Ressonância Magnética , Neoplasias da Próstata/patologia , Área Sob a Curva , Neoplasias Ósseas/secundário , Humanos , Masculino , Curva ROC , Sensibilidade e Especificidade
20.
Clin Nucl Med ; 49(9): e439-e440, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38598475

RESUMO

ABSTRACT: A 17-year-old man presented with dull pain in the left upper abdomen for 1 month. Initial CT and gastroscopy revealed a mass in the gastric fundas, protruding into the lumen. Based on findings of a fine-needle biopsy, an inflammatory myofibroblastic tumor was suspected. Subsequent PET/CT showed increased FDG uptake in the gastric fundas as well as hepatogastric ligament, para-aortic region. Eventually, he underwent surgical resection, and histopathologic findings confirmed the diagnosis of splenosis.


Assuntos
Fluordesoxiglucose F18 , Fundo Gástrico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Esplenose , Neoplasias Gástricas , Tomografia Computadorizada por Raios X , Humanos , Masculino , Esplenose/diagnóstico por imagem , Adolescente , Diagnóstico Diferencial , Fundo Gástrico/diagnóstico por imagem , Fundo Gástrico/patologia , Neoplasias Gástricas/diagnóstico por imagem , Imagem Multimodal
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