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1.
PLoS One ; 16(10): e0258214, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669702

RESUMO

High accuracy has been reported in deep learning classification for amyloid brain scans, an important factor in Alzheimer's disease diagnosis. However, the possibility of overfitting should be considered, as this model is fitted with sample data. Therefore, we created and evaluated an [18F]Florbetaben amyloid brain positron emission tomography (PET) scan classification model with a Dong-A University Hospital (DAUH) dataset based on a convolutional neural network (CNN), and performed external validation with the Alzheimer's Disease Neuroimaging Initiative dataset. Spatial normalization, count normalization, and skull stripping preprocessing were performed on the DAUH and external datasets. However, smoothing was only performed on the external dataset. Three types of models were used, depending on their structure: Inception3D, ResNet3D, and VGG3D. After training with 80% of the DAUH dataset, an appropriate model was selected, and the rest of the DAUH dataset was used for model evaluation. The generalization potential of the selected model was then validated using the external dataset. The accuracy of the model evaluation for Inception3D, ResNet3D, and VGG3D was 95.4%, 92.0%, and 97.7%, and the accuracy of the external validation was 76.7%, 67.1%, and 85.3%, respectively. Inception3D and ResNet3D were retrained with the external dataset; then, the area under the curve was compared to determine the binary classification performance with a significance level of less than 0.05. When external validation was performed again after fine tuning, the performance improved to 15.3%p for Inception3D and 16.9%p for ResNet3D. In [18F]Florbetaben amyloid brain PET scan classification using CNN, the generalization potential can be seen through external validation. When there is a significant difference between the model classification performance and the external validation, changing the model structure or fine tuning the model can help improve the classification performance, and the optimal model can also be found by collaborating through a web-based open platform.


Assuntos
Compostos de Anilina/química , Encéfalo/diagnóstico por imagem , Imageamento Tridimensional , Redes Neurais de Computação , Tomografia por Emissão de Pósitrons , Estilbenos/química , Idoso , Bases de Dados como Assunto , Feminino , Humanos , Masculino , Modelos Biológicos , Curva ROC , Reprodutibilidade dos Testes
2.
Medicine (Baltimore) ; 100(35): e26961, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477126

RESUMO

BACKGROUND: The quantification of heterogeneity for the striatum and whole brain with F-18 FP-CIT PET images will be useful for diagnosis. The index obtained from texture analysis on PET images is related to pathological change that the neuronal loss of the nigrostriatal tract is heterogeneous according to the disease state. The aim of this study is to evaluate various heterogeneity indices of F-18 FP-CIT PET images in the diagnosis of Parkinson's disease (PD) patients and to access the diagnostic accuracy of the indices using machine learning (ML). METHODS: This retrospective study included F-18 FP-CIT PET images of 31 PD and 31 age-matched health controls (HC). The volume of interest was delineated according to iso-contour lines around standardized uptake value (SUV) 3.0 g/ml for each region of the striatum by PMod 3.603. One hundred eight heterogeneity indices were calculated using CGITA to find indices from which the PD and HC were classified using statistical significance. PD group was classified by constructing a 2-dimensional or 3-dimensional phase space quantifier using these heterogeneity indices. We used 71 heterogeneity indices to classify PD from HC using ML for dimensional reduction. RESULTS: The heterogeneity indices for classifying PD from HC were size-zone variability, contrast, inverse difference-moment, and homogeneity in the order of low P value. Three-dimensional quantifiers composed of normalized-contrast, code-similarity, and contrast were more clearly classified than 2-dimensional ones. After 71-dimensional reduction using PCA, classification was possible by logistic regression with 91.3% accuracy. The 2 groups were classified with an accuracy of 85.5% using the support vector machine and 88.4% using the random forest. The classification accuracy using the eXtreme Gradient Boosting was 95.7%, and feature importance was highest in order of SUV bias-corrected kurtosis, size-zone-variability, intensity-variability, and high-intensity-zone-variability. CONCLUSION: It was confirmed that PD patients is more clearly classified than the conventional 2-dimensional quantifier by introducing a 3-dimensional phase space quantifier. We observed that ML can be used to classify the 2 groups in an easy and explanatory manner. For the discrimination of the disease, 24 heterogeneity indices were found to be statistically useful, and the major cut-off values of 3 heterogeneity indices were size-zone variability (1906.44), intensity variability (129.21), and high intensity zone emphasis (800.29).


Assuntos
Doença de Parkinson/diagnóstico , Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Idoso , Feminino , Fluordesoxiglucose F18/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem/métodos , Neuroimagem/estatística & dados numéricos , Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Estudos Retrospectivos
3.
Sci Rep ; 11(1): 4825, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649403

RESUMO

Our purpose in this study is to evaluate the clinical feasibility of deep-learning techniques for F-18 florbetaben (FBB) positron emission tomography (PET) image reconstruction using data acquired in a short time. We reconstructed raw FBB PET data of 294 patients acquired for 20 and 2 min into standard-time scanning PET (PET20m) and short-time scanning PET (PET2m) images. We generated a standard-time scanning PET-like image (sPET20m) from a PET2m image using a deep-learning network. We did qualitative and quantitative analyses to assess whether the sPET20m images were available for clinical applications. In our internal validation, sPET20m images showed substantial improvement on all quality metrics compared with the PET2m images. There was a small mean difference between the standardized uptake value ratios of sPET20m and PET20m images. A Turing test showed that the physician could not distinguish well between generated PET images and real PET images. Three nuclear medicine physicians could interpret the generated PET image and showed high accuracy and agreement. We obtained similar quantitative results by means of temporal and external validations. We can generate interpretable PET images from low-quality PET images because of the short scanning time using deep-learning techniques. Although more clinical validation is needed, we confirmed the possibility that short-scanning protocols with a deep-learning technique can be used for clinical applications.

4.
Clin Pract ; 10(1): 1216, 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32266055

RESUMO

Osteosarcoma is the most common malignant bone tumor and is known to occur mainly in the metaphyses of long bones. However, a few cases of osteosarcoma in talus have been reported in older patients. We experienced an osteosarcoma of an 80-year-old male patient with a talus which is rarely reported and evaluated disease patterns with four different imaging modalities.

5.
PLoS One ; 15(3): e0229860, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32134983

RESUMO

PURPOSE: We have evaluated the clinical significance of the washout rate (WR) on I-123 MIBG scans through the analysis of the relationship between the I-123 MIBG scans and autonomic status in patients with Parkinson's disease (PD). MATERIALS AND METHODS: Sixty patients with clinical PD who had decreased HMR were enrolled. An autonomic symptom was evaluated using a head-up tilt test and the Composite Autonomic Severity Score (CASS). An I-123 MIBG scan and F-18 FP-CIT positron emission tomography (PET) were performed. All of the patients were classified into three groups according to the WR. The differences in patient characteristics and the imaging parameters among the three groups were evaluated, and a correlation analysis was also performed. RESULTS: The frequency of orthostatic hypotension was significantly different among the three groups. The difference in systolic pressure (dSysPr) and the difference in diastolic pressure (dDiaPr) of group 3 was significantly larger than those of groups 1 and 2. From the correlation analysis, it can be seen that age, Hoehn and Yahr (H&Y) stage, dSysPr, and dDiaPr had a weak positive correlation with the WR. The total CASS score was significantly higher in group 3 compared with groups 1 and 2. The WR had a moderate positive correlation with the cardiosympathetic score and the total CASS score. CONCLUSION: The WR is related to autonomic dysfunction. An I-123 MIBG cardiac scan is considered to be a good method to evaluate not only the differential diagnosis of Parkinson's disease but also the degree of autonomic dysfunction.


Assuntos
3-Iodobenzilguanidina/administração & dosagem , Sistema Nervoso Autônomo/diagnóstico por imagem , Radioisótopos do Iodo/administração & dosagem , Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos/administração & dosagem , 3-Iodobenzilguanidina/metabolismo , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Feminino , Radioisótopos de Flúor/administração & dosagem , Radioisótopos de Flúor/metabolismo , Coração/diagnóstico por imagem , Humanos , Hipotensão Ortostática/diagnóstico , Radioisótopos do Iodo/metabolismo , Masculino , Mediastino/diagnóstico por imagem , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/metabolismo , Estudos Retrospectivos , Tropanos/administração & dosagem , Tropanos/metabolismo
6.
Nucl Med Mol Imaging ; 53(5): 328-333, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31723362

RESUMO

Purpose: F-18 florapronol (FPN) is the commercially recognized beta-amyloid positron emission tomography (PET) radiotracer in Korea. This study compared the early F-18 florapronol PET with F-18 fluorodeoxyglucose (FDG) PET between healthy controls (HC) and Alzheimer's dementia (AD) patients. Methods: A total of 29 subjects (15 HC and 14 AD subjects) underwent F-18 FPN PET and F-18 FDG PET. F-18 FDG PET image was acquired from 30 to 60 min and F-18 FPN PET for 0 to 10 min. F-18 FPN and F-18 FDG images were spatially normalized with transformation matrices obtained from individual CT images and standardized uptake value ration (SUVR) from cerebellum area, and the global mean was calculated using PMOD 3.6. Pearson's correlation coefficients between F-18 FDG and early F-18 FPN for predefined cortical brain regions were calculated. Results: We compared the F-18 FDG and F-18 FPN for SUVR of a specific region in global mean normalization and cerebellum normalization, and most of the correlation coefficient was higher in global mean normalization. In global mean normalization, the correlation coefficient for SUVR of HC was higher than that of AD in all brain regions. Conclusions: Early F-18 FPN study can be used as a proxy marker for the F-18 FDG PET.

7.
Nucl Med Mol Imaging ; 53(5): 334-339, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31723363

RESUMO

Purpose: To investigate regional cerebral amyloid beta retention in cognitively normal Korean adults using F-18 florbetaben (FBB). Methods: We prospectively analyzed F-18 FBB positron emission tomography (PET)/CT scans of 30 cognitively healthy adults (age range, 50-70 years) using automated quantification. The standardized uptake value ratios (SUVRs) of F-18 FBB were calculated for predefined regions by normalizing the regional count with cerebellar cortex. Results: The distribution of amyloid beta for each brain region revealed no age-related trends (p > 0.05). From all subjects, mean SUVR of amyloid deposit was 1.30 ± 0.18. The right parietal lobe showed the highest SUVR value (1.46 ± 0.23), whereas the right frontal lobe and left precuneus showed the lowest SUVR (1.23 ± 0.25). Conclusions: We provide reference values of normative data obtained from healthy elderly Koreans and suggest its use for accurate diagnosis of patients with Alzheimer's disease.

8.
Clin Interv Aging ; 14: 1167-1175, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303750

RESUMO

Purpose: We assessed the effect of home-based cognitive intervention (HCI) on cognitive function along with brain metabolism by 18F-FDG PET in patients with amnestic MCI (aMCI). Patients and methods: Fifty-seven patients with aMCI from three hospitals were randomized (30 HCI, 27 control). For 12 weeks, subjects received HCI. Thirty-two subjects (15 HCI, 17 control) underwent brain 18-F-FDG-PET imaging at baseline and at 12 and 24 weeks. Results: The HCI group showed significant improvement in the scores of the Controlled Oral Word Association Test (COWAT) 12 and at 24 weeks. Significant brain metabolic changes by 18F-FDG PET were not observed. Conclusion: The current study suggests that HCI was effective in improving general cognition along with frontal executive function in patients with aMCI.


Assuntos
Cognição , Terapia Cognitivo-Comportamental/métodos , Disfunção Cognitiva/reabilitação , Idoso , Encéfalo/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Função Executiva , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons/métodos , Resultado do Tratamento
9.
Dement Neurocogn Disord ; 18(1): 19-29, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31097969

RESUMO

Background and Purpose: Subjective cognitive decline (SCD) may be the first symptomatic stage of Alzheimer's disease (AD). Hence, a screening tool to characterize the patients' complaints and assess the risk of AD is required. We investigated the SCD neuroimaging biomarker distributions and the relevance between the self-report questionnaire and Alzheimer's pathologic changes. Methods: Individuals aged 50 and above with consistent cognitive complaints without any objective cognitive impairments were eligible for the study. The newly developed questionnaire consisted of 2 parts; 10 questions translated from the 'SCD-plus criteria' and a Korean version of the cognitive failure questionnaire by Broadbent. All the subjects underwent physical examinations such as blood work, detailed neuropsychological tests, the self-report questionnaire, brain magnetic resonance imagings, and florbetaben positron emission tomography (PET) scans. Amyloid PET findings were interpreted using both visual rating and quantitative analysis. Group comparisons and association analysis were performed using SPSS (version 18.0). Results: A total of 31 participants with SCD completed the study and 25.8% showed positive amyloid depositions. The degree of periventricular white matter hyperintensities (WMH) and hippocampal atrophy were more severe in amyloid-positive SCDs compared to the amyloid-negative group. In the self-reported questionnaire, the 'informant's report a decline' and 'symptom's onset after 65 years of age' were associated with more Alzheimer's pathologic changes. Conclusions: Amyloid-positive SCDs differed from amyloid-negative SCDs on WMH, hippocampal atrophy, and a few self-reported clinical features, which gave clues on the prediction of AD pathology.

10.
Dement Neurocogn Disord ; 18(4): 130-137, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31942172

RESUMO

Background and Purpose: Mild cognitive impairment (MCI) is a prodromal stage of dementia. Amyloid deposits in positron-emission tomography (PET) imaging of MCI patients imply a higher risk for advancing to dementia, with rates of 10%-15% yearly. The purpose of this study was to investigate the clinical characteristics of subgroups of amnestic MCI (aMCI) that may have a higher impact on amyloid positivity. Methods: We recruited 136 aMCI patients. All patients underwent a 20-minute F-18 florbetaben or flutemetamol PET scan. We classified amyloid PET images as positive or negative according to a semi-quantitative method. We evaluated the amyloid positivity of subgroups of aMCI (early vs. late type, single vs. multiple amnestic type, verbal vs. verbal, and visual amnestic type), and compared baseline clinical characteristics including key risk factors, apolipoprotein E4 (apoE4) genotype, and neuropsychological assessments with amyloid positivity in aMCI. Results: The amyloid positivity in total aMCI was 41%. The positivity rate according to subgroup of aMCI were as follow: Late aMCI (49%) vs. early aMCI (33%) (p=0.13), multiple aMCI (40%) vs. single aMCI (38%) (p=0.51), and verbal and visual aMCI (59%) vs. verbal aMCI (35%) (p=0.01), respectively. The mean age and the frequency of apoE4 allele of the amyloid-positive group was higher than that of the amyloid-negative group in aMCI (p<0.01). Conclusions: We found that the amyloid positivity was related to patterns of clinical subtypes, characteristics, and risk factors in patients with aMCI.

11.
J Alzheimers Dis ; 66(2): 681-691, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30320571

RESUMO

BACKGROUND: Most clinical trials focus on amyloid-ß positive (Aß+) amnestic mild cognitive impairment (aMCI), but screening failures are high because only a half of patients with aMCI are positive on Aß PET. Therefore, it becomes necessary for clinicians to predict which patients will have Aß biomarker. OBJECTIVE: We aimed to compare clinical factors, neuropsychological (NP) profiles, and apolipoprotein E (APOE) genotype between Aß+ aMCI and Aß-aMCI and to develop a clinically useful prediction model of Aß positivity on PET (PET-Aß+) in aMCI using a nomogram. METHODS: We recruited 523 aMCI patients who underwent Aß PET imaging in a nation-wide multicenter cohort. The results of NP measures were divided into following subgroups: 1) Stage (Early and Late-stage), 2) Modality (Visual, Verbal, and Both), 3) Recognition failure, and 4) Multiplicity (Single and Multiple). A nomogram for PET-Aß+ in aMCI patients was constructed using a logistic regression model. RESULTS: PET-Aß+ had significant associations with NP profiles for several items, including high Clinical Dementia Rating Scale Sum of Boxes score (OR 1.47, p = 0.013) and impaired memory modality (impaired both visual and verbal memories compared with visual only, OR 3.25, p = 0.001). Also, presence of APOEɛ4 (OR 4.14, p < 0.001) was associated with PET-Aß+. These predictors were applied to develop the nomogram, which showed good prediction performance (C-statistics = 0.79). Its prediction performances were 0.77/0.74 in internal/external validation. CONCLUSIONS: The nomogram consisting of NP profiles, especially memory domain, and APOEɛ4 genotype may provide a useful predictive model of PET-Aß+ in patients with aMCI.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Nomogramas , Tomografia por Emissão de Pósitrons , Idoso , Idoso de 80 Anos ou mais , Compostos de Anilina/farmacocinética , Apolipoproteínas E/genética , Disfunção Cognitiva/genética , Estudos de Coortes , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Reprodutibilidade dos Testes , Estilbenos/farmacocinética
12.
Nucl Med Mol Imaging ; 52(5): 384-388, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30344788

RESUMO

Primary progressive aphasia (PPA) is a heterogenous neurodegenerative disorder characterized by declining language and speech ability. Various underlying neuropathologies can induce PPA, and the disorder is divided into three subtypes-progressive non-fluent aphasia, semantic variant aphasia, and logopenic aphasia-according to clinical features. Accurate disease classification and prediction of underlying diseases are necessary for appropriate treatment, but proper use of imaging tests is important because clinical information alone often makes it difficult to make accurate decisions. Because there is a characteristic metabolic pattern according to the subtypes, F-18 fluorodeoxyglucose positron emission tomography (PET) can indicate subtype classification. In addition, PET studies for imaging amyloid or dopamine transporters play an important role in demonstrating underlying disease. The present case showed that PET imaging studies are useful in diagnosis and could be used as a biomarker in PPA.

13.
Sci Rep ; 8(1): 13236, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-30185806

RESUMO

Utilizing the publicly available neuroimaging database enabled by Alzheimer's disease Neuroimaging Initiative (ADNI; http://adni.loni.usc.edu/ ), we have compared the performance of automated classification algorithms that differentiate AD vs. normal subjects using Positron Emission Tomography (PET) with fluorodeoxyglucose (FDG). General linear model, scaled subprofile modeling and support vector machines were examined. Among the tested classification methods, support vector machine with Iterative Single Data Algorithm produced the best performance, i.e., sensitivity (0.84) × specificity (0.95), by 10-fold cross-validation. We have applied the same classification algorithm to four different datasets from ADNI, Health Science Centre (Winnipeg, Canada), Dong-A University Hospital (Busan, S. Korea) and Asan Medical Centre (Seoul, S. Korea). Our data analyses confirmed that the support vector machine with Iterative Single Data Algorithm showed the best performance in prediction of future development of AD from the prodromal stage (mild cognitive impairment), and that it was also sensitive to other types of dementia such as Parkinson's Disease Dementia and Dementia with Lewy Bodies, and that perfusion imaging using single photon emission computed tomography may achieve a similar accuracy to that of FDG-PET.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença por Corpos de Lewy/diagnóstico por imagem , Aprendizado de Máquina , Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluordesoxiglucose F18/análise , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem/métodos , Tomografia por Emissão de Pósitrons/métodos , Máquina de Vetores de Suporte
14.
Eur J Nucl Med Mol Imaging ; 45(13): 2482-2483, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30221329

RESUMO

Unfortunately, the original version of this article contained several errors made during final step of article production. In the results section (fourth sentence) of the Abstract, the incomplete sentence,", 31.4% in high-risk group and 4.7% in treatment failure group.

15.
Eur J Nucl Med Mol Imaging ; 45(13): 2274-2284, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30056546

RESUMO

PURPOSE: The aim of this study was to establish a risk-stratification model integrating posttreatment metabolic response using the Deauville score and the pretreatment National Comprehensive Cancer Network-International Prognostic Index (NCCN-IPI) in nodal PTCLs. METHODS: We retrospectively analysed 326 patients with newly diagnosed nodal PTCLs between January 2005 and June 2016 and both baseline and posttreatment PET/CT data. The final model was validated using an independent prospective cohort of 79 patients. RESULTS: Posttreatment Deauville score (1/2, 3, and 4/5) and the NCCN-IPI (low, low-intermediate, high-intermediate, and high) were independently associated with progression-free survival: for the Deauville score, the hazard ratios (HRs) were 1.00 vs. 2.16 (95% CI 1.47-3.18) vs. 7.86 (5.66-10.92), P < 0.001; and for the NCCN-IPI, the HRs were 1.00 vs. 2.31 (95% CI 1.20-4.41) vs. 4.42 (2.36-8.26) vs. 7.09 (3.57-14.06), P < 0.001. Based on these results, we developed a simplified three-group risk model comprising a low-risk group (low or low-intermediate NCCN-IPI with a posttreatment Deauville score of 1 or 2, or low NCCN-IPI with a Deauville score of 3), a high-risk group (high or high-intermediate NCCN-IPI with a Deauville score of 1/2 or 3, or low-intermediate NCCN-IPI with a Deauville score of 3), and a treatment failure group (Deauville score 4 or 5). This model was significantly associated with progression-free survival (5-year, 70.3%, 31.4%, and 4.7%; P < 0.001) and overall survival (5-year, 82.1%, 45.5%, and 14.7%; P < 0.001). Similar associations were also observed in the independent validation cohort. CONCLUSION: The risk-stratification model integrating posttreatment Deauville score and pretreatment NCCN-IPI is a powerful tool for predicting treatment failure in patients with nodal PTCLs.


Assuntos
Linfoma de Células T Periférico/terapia , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Linfoma de Células T Periférico/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Retrospectivos , Medição de Risco
16.
BMC Neurosci ; 19(1): 45, 2018 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-30053803

RESUMO

BACKGROUND: Although amyloid beta (Aß) imaging is widely used for diagnosing and monitoring Alzheimer's disease in clinical fields, paralleling comparison between 18F-flutemetamol and 18F-florbetaben was rarely attempted in AD mouse model. We performed a comparison of Aß PET images between 18F-flutemetamol and 18F-florbetaben in a recently developed APPswe mouse model, C57BL/6-Tg (NSE-hAPPsw) Korl. RESULTS: After an injection (0.23 mCi) of 18F-flutemetamol and 18F-florbetaben at a time interval of 2-3 days, we compared group difference of SUVR and kinetic parameters between the AD (n = 7) and control (n = 7) mice, as well as between 18F-flutemetamol and 18F-florbetaben image. In addition, bio-distribution and histopathology were conducted. With visual image and VOI-based SUVR analysis, the AD group presented more prominent uptake than did the control group in both the 18F-florbetaben and 18F-flutemetamol images. With kinetic analysis, the 18F-florbetaben images showed differences in K1 and k4 between the AD and control groups, although 18F-flutemetamol images did not show significant difference. 18F-florbetaben images showed more prominent cortical uptake and matched well to the thioflavin S staining images than did the 18F-flutemetamol image. In contrast, 18F-flutemetamol images presented higher K1, k4, K1/k2 values than those of 18F-florbetaben images. Also, 18F-flutemetamol images presented prominent uptake in the bowel and bladder, consistent with higher bio-distribution in kidney, lung, blood and heart. CONCLUSIONS: Compared with 18F-flutemetamol images, 18F-florbetaben images showed prominent visual uptake intensity, SUVR, and higher correlations with the pathology. In contrast, 18F-flutemetamol was more actively metabolized than was 18F-florbetaben (Son et al. in J Nucl Med 58(Suppl 1):S278, 2017].


Assuntos
Peptídeos beta-Amiloides/metabolismo , Mapeamento Encefálico , Encéfalo/patologia , Processamento de Imagem Assistida por Computador , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Compostos de Anilina/farmacologia , Animais , Encéfalo/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Masculino , Camundongos Transgênicos , Tomografia por Emissão de Pósitrons/métodos , Estilbenos/farmacologia
17.
Neurocase ; 24(2): 83-89, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29508646

RESUMO

This study aimed to detect different patterns of cerebral hypoperfusion in DLB according to clinical staging. Thirty-three patients with DLB were recruited by clinical dementia rating (CDR) stage. Compared with control, cerebral hypoperfusion was mainly observed in the lingual gyrus, the cuneus, the occipital gyrus in CDR 0.5 group; the fusiform gyrus, the middle temporal gyrus, and the posterior cingulate in CDR 1; and the lingual gyrus, the cuneus, the hippocampus, the fusiform gyrus, and the inferior frontal gyrus in CDR 2. Our findings suggest that cerebral hypoperfusion spreads to the frontal cortex and temporal lobes as disease progresses.


Assuntos
Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/fisiopatologia , Progressão da Doença , Doença por Corpos de Lewy/fisiopatologia , Idoso , Córtex Cerebral/diagnóstico por imagem , Circulação Cerebrovascular , Feminino , Lobo Frontal/irrigação sanguínea , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiopatologia , Humanos , Doença por Corpos de Lewy/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Lobo Temporal/irrigação sanguínea , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiopatologia , Tomografia Computadorizada de Emissão de Fóton Único
18.
J Allergy Clin Immunol ; 141(3): 938-950.e12, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29225084

RESUMO

BACKGROUND: Eosinophilic inflammation is a major pathologic feature of chronic rhinosinusitis (CRS) and is frequently associated with severe refractory disease. Prostaglandin (PG) D2 levels are increased in patients with CRS, and PGD2 is an important contributing factor to eosinophilic inflammation. Autophagy has a pleiotropic effect on immune responses and disease pathogenesis. Recent studies suggest the potential involvement of autophagy in patients with CRS and the PG pathway. OBJECTIVE: We sought to investigate whether altered function of autophagy is associated with eosinophilic inflammation and dysregulated production of PGD2 in patients with CRS. METHODS: We used myeloid cell-specific deletion of autophagy-related gene 7 (Atg7), which is vital for autophagy, and investigated the effects of impaired autophagy on eosinophilic inflammation in a murine model of eosinophilic chronic rhinosinusitis (ECRS). The effect of autophagy on PGD2 production and gene expression profiles associated with allergy and the PG pathway were assessed. RESULTS: We found that impaired autophagy in myeloid cells aggravated eosinophilia, epithelial hyperplasia, and mucosal thickening in mice with ECRS. This aggravation was associated with gene expression profiles that favor eosinophilic inflammation, TH2 response, mast cell infiltration, and PGD2 dysregulation. Supporting this, PGD2 production was also increased significantly by impaired autophagy. Among other myeloid cells, macrophages were associated with autophagy deficiency, leading to increased IL-1ß levels. Macrophage depletion or blockade of IL-1 receptor led to alleviation of eosinophilic inflammation and sinonasal anatomic abnormalities associated with autophagy deficiency. CONCLUSION: Our results suggest that impaired autophagy in myeloid cells, particularly macrophages, has a causal role in eosinophilic inflammation and ECRS pathogenesis.


Assuntos
Proteína 7 Relacionada à Autofagia/imunologia , Autofagia/imunologia , Eosinofilia/imunologia , Rinite/imunologia , Transdução de Sinais/imunologia , Sinusite/imunologia , Animais , Autofagia/genética , Proteína 7 Relacionada à Autofagia/genética , Modelos Animais de Doenças , Eosinofilia/genética , Eosinofilia/patologia , Inflamação , Camundongos , Camundongos Transgênicos , Rinite/genética , Rinite/patologia , Transdução de Sinais/genética , Sinusite/genética , Sinusite/patologia
19.
Medicine (Baltimore) ; 96(48): e9042, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29310421

RESUMO

In Alzheimer disease (AD), neuroinflammation is an important process related to the deposition of beta-amyloid plaques and the activation of microglia. The inflammatory process can occur in both the gray matter and the white matter. We evaluated glucose metabolism of the white matter in AD patients and compared the value with cognitive parameters of the patients.Eighteen AD patients and 18 healthy subjects underwent F-18 fluorodeoxyglucose (FDG) and F-18 florbetaben positron emission tomography (PET). After segmentation of the white matter in both PET images, the specific binding ratio (SBR) of the global and regional cerebral white matter was checked. We evaluated the differences in SBR of the global and regional white matter between AD patients and healthy subjects. Then, we assessed the correlation between SBR and cognitive parameters in AD patients.In F-18 FDG PET images, the global white matter SBR was significantly higher in AD patients than in healthy subjects. In the regional analysis, the white matter SBR was significantly higher for the frontal, temporal, and parietal areas in AD patients. In the correlation analysis with F-18 FDG PET, SBR was significantly correlated with the Global Deterioration Scale, Mini-Mental State Examination scores, and amyloid deposition.Glucose metabolism of the white matter was significantly higher in AD patients than in healthy subjects and it was related to the scores of cognitive parameters. We suggest that F-18 FDG PET, like 18-kDa translocator protein PET, could be used as an indicator of neuroinflammation; however, further research is needed for a direct comparison between the 2 tests.


Assuntos
Doença de Alzheimer/metabolismo , Amiloide/metabolismo , Encéfalo/metabolismo , Glucose/metabolismo , Tomografia por Emissão de Pósitrons , Substância Branca/metabolismo , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/psicologia , Compostos de Anilina , Encéfalo/diagnóstico por imagem , Cognição , Feminino , Fluordesoxiglucose F18 , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Estilbenos , Substância Branca/diagnóstico por imagem
20.
Contrast Media Mol Imaging ; 2017: 8598705, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29333110

RESUMO

We evaluated the difference in the status of dopamine transporters (DATs) depending on Parkinsonism, cerebellar, and autonomic features using F-18 FP-CIT positron emission tomography (PET) in multiple system atrophy with cerebellar ataxia (MSA-C). We also assessed whether the DAT PET could be useful in the management of MSA-C. Forty-nine patients who were clinically diagnosed as possible to probable MSA-C were included. Based on the F-18 FP-CIT PET results, patients were classified into normal (n = 25) and abnormal (n = 24) scan groups. There were statistically significant differences in rigidity, bradykinesia, postural instability, asymmetry, and specific uptake ratio (SUR) between the two groups but no significant differences in tremor and cerebellar/autonomic symptoms. Dopaminergic medications were administered to 22 patients. All seven patients with normal scans showed no change, while 10 of the 15 patients with abnormal scans showed clinical improvement. There was a trend of a negative correlation between levodopa equivalent dose and SUR, but it was not statistically significant. DAT imaging, such as F-18 FP-CIT PET, may be useful in predicting the response to dopaminergic medication regardless of cerebellar/autonomic symptoms in MSA-C. In addition to being used for the diagnosis of the disease, it may be used as a treatment decision index.


Assuntos
Ataxia Cerebelar , Levodopa/administração & dosagem , Atrofia de Múltiplos Sistemas , Tomografia por Emissão de Pósitrons , Tropanos/administração & dosagem , Idoso , Ataxia Cerebelar/diagnóstico por imagem , Ataxia Cerebelar/tratamento farmacológico , Ataxia Cerebelar/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Atrofia de Múltiplos Sistemas/tratamento farmacológico , Atrofia de Múltiplos Sistemas/metabolismo
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