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1.
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
2.
Sci Rep ; 11(1): 4825, 2021 Mar 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.

3.
Phys Rev E ; 101(1-1): 012704, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32069560

RESUMO

Dielectrophoresis (DEP) in a medium with anisotropic dielectric susceptibility is very different from typical DEP in an isotropic medium: The direction of particle actuation can be switched depending on the direction of the susceptibility tensor of the medium. However, the understanding of switchable DEP (SDEP) in an anisotropic medium is still in its infant stage. Here, we investigate SDEP using heat-generated isotropic droplets in a nematic liquid crystal (LC) medium. We demonstrate that the location of the generation of isotropic droplets can be partially controlled by controlling the temperature gradient within the LC cell using dielectric loss. The SDEP actuation of isotropic droplets is also highly dependent on the location of the isotropic droplets. Using this method, we fabricated different array patterns of isotropic and nematic phase separations under different applied signals.

4.
Adv Sci (Weinh) ; 6(17): 1900785, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31508284

RESUMO

Microfabrication of complex double emulsion droplets with controlled substructures, which resemble biological cells, is an important but a highly challenging subject. Here, a new approach is proposed based on laser-induced injection of water nanodroplets into a liquid crystal (LC) drop. In contrast to the conventional top-down microfluidic fabrication, this method employs a series of bottom-up strategies such as nanodroplet injection, spontaneous and assisted coalescence, elastically driven actuation, and self-assembly. Each step is controlled precisely by adjusting the laser beam, interfacial tension, and its gradients, surface anchoring, and elasticity of the LC. Whispering gallery mode illumination is used to monitor the injection of droplets. A broad spectrum of double emulsions with a predesigned hierarchical architecture is fabricated and reconfigured by temperature, laser-induced coalescence, and injection. The proposed bottom-up method to produce customized microemulsions that are responsive to environmental cues can be used in the development of drug delivery systems, biosensors, and functional soft matter microstructures.

5.
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
6.
Environ Sci Pollut Res Int ; 25(30): 30044-30055, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30076551

RESUMO

A number of severe norovirus outbreaks due to the consumption of contaminated shellfish have been reported recently. In this study, we evaluated the distribution of coliphage densities to determine their efficacy as fecal indicators of enteric viruses, including noroviruses, in water samples collected from a shellfish growing area in Republic of Korea over a period of approximately 1 year. Male-specific and somatic coliphages in water samples were analyzed using the single agar layer method, and norovirus genogroups I and II, which infect mainly humans, were analyzed using duplex reverse transcription quantitative PCR. Male-specific and somatic coliphages were detected widely throughout the study area. Several environmental parameters, including salinity, precipitation, temperature, and wind speed were significantly correlated with coliphage concentrations (P < 0.05). Moreover, the concentrations of male-specific coliphages were positively correlated with the presence of human noroviruses (r = 0.443; P < 0.01). The geospatial analysis with coliphage concentrations using a geographic information system revealed that densely populated residential areas were the major source of fecal contamination. Our results indicate that coliphage monitoring in water could be a useful approach to prevent norovirus contamination in shellfish.


Assuntos
Colífagos/isolamento & purificação , Norovirus/isolamento & purificação , Frutos do Mar/virologia , Animais , Colífagos/classificação , Colífagos/genética , Monitoramento Ambiental , Fezes/virologia , Contaminação de Alimentos/análise , Sistemas de Informação Geográfica , Humanos , Norovirus/classificação , Norovirus/genética , República da Coreia , Microbiologia da Água
7.
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
8.
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
9.
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
10.
Nucl Med Mol Imaging ; 50(4): 308-321, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27994686

RESUMO

PURPOSE: We investigated the visual tracer distribution pattern and serial changes in uptake ratio in different anatomical zones during the natural postoperative course in order to establish a reference for evaluation of patients with complications. METHODS: A total of 36 patients without symptoms after hip or knee arthroplasty were grouped according to the interval between surgery and the scan. The serial changes in SUVmean in each periprosthetic zone were quantified using the volume of interest isocontour method. Images were classified according to the uptake distribution pattern. The uptake ratios in the postoperative period groups were then compared using the Kruskal-Wallis test. The correlation between uptake ratio and postoperative period was then determined. RESULTS: Tracer distribution patterns in hip prostheses were classified into three types and the patterns in knee prostheses into five types. In hip prostheses, intense osteoblastic activity was observed during 3-6 months and then declined in most patients, but showed a slight increase over 15-25 months in 5-10 % of patients. The correlation coefficients varied among the zones. Significant differences in uptake ratios among the period groups was found for all zones, except zone 8. Porous coated areas showed higher uptake than uncoated areas only for the period the 3-6 months. In knee prostheses, uptake ratios showed a curvilinear pattern, increasing from 3-6 to 8-15 months and declining later. The uptake ratios were different among the period groups. Every zone showed a positive correlation from 3-6 to 8-15 months, and negative correlations from 8-15 to 22-25 months. CONCLUSIONS: This is the first 18F-sodium fluoride PET/CT study investigating the stability of implants and sets a reference for evaluation of patients with complications.

11.
Biomed Res Int ; 2016: 7862539, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27872857

RESUMO

We integrated visual and quantitative methods for analyzing the stability of respiration using four methods: phase space diagrams, Fourier spectra, Poincaré maps, and Lyapunov exponents. Respiratory patterns of 139 patients were grouped based on the combination of the regularity of amplitude, period, and baseline positions. Visual grading was done by inspecting the shape of diagram and classified into two states: regular and irregular. Quantitation was done by measuring standard deviation of x and v coordinates of Poincaré map (SD x , SD v ) or the height of the fundamental peak (A1) in Fourier spectrum or calculating the difference between maximal upward and downward drift. Each group showed characteristic pattern on visual analysis. There was difference of quantitative parameters (SD x , SD v , A1, and MUD-MDD) among four groups (one way ANOVA, p = 0.0001 for MUD-MDD, SD x , and SD v , p = 0.0002 for A1). In ROC analysis, the cutoff values were 0.11 for SD x (AUC: 0.982, p < 0.0001), 0.062 for SD v (AUC: 0.847, p < 0.0001), 0.117 for A1 (AUC: 0.876, p < 0.0001), and 0.349 for MUD-MDD (AUC: 0.948, p < 0.0001). This is the first study to analyze multiple aspects of respiration using various mathematical constructs and provides quantitative indices of respiratory stability and determining quantitative cutoff value for differentiating regular and irregular respiration.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Técnicas de Imagem de Sincronização Respiratória/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Fenômenos Fisiológicos Respiratórios
12.
PLoS One ; 11(9): e0163800, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27681683

RESUMO

The presence of human norovirus in the aquatic environment can cause outbreaks related to recreational activities and the consumption of norovirus-contaminated clams. In this study, we investigated the prevalence of norovirus genogroups I (GI) and II (GII) in the coastal aquatic environment in South Korea (March 2014 to February 2015). A total of 504 water samples were collected periodically from four coastal areas (total sites = 63), of which 44 sites were in estuaries (clam fisheries) and 19 were in inflow streams. RT-PCR analysis targeting ORF2 region C revealed that 20.6% of the water samples were contaminated by GI (13.3%) or GII (16.6%). The prevalence of human norovirus was higher in winter/spring than in summer/fall, and higher in inflow streams (50.0%) than in estuaries (7.9%). A total of 229 human norovirus sequences were identified from the water samples, and phylogenetic analysis showed that the sequences clustered into eight GI genotypes (GI.1, 2, 3, 4, 5, 6, 7, and 9) and nine GII genotypes (GII.2, 3, 4, 5, 6, 11, 13, 17, and 21). This study highlighted three issues: 1) a strong correlation between norovirus contamination via inflow streams and coastal areas used in clam fisheries; 2) increased prevalence of certain non-GII.4 genotypes, exceeding that of the GII.4 pandemic variants; 3) seasonal shifts in the dominant genotypes of both GI and GII.

13.
Ann Nucl Med ; 30(8): 572-8, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27283185

RESUMO

OBJECTIVE: We applied a simple isocontour volume-of-interest (VOI) method to analyze the whole striatum in an F-18 FP-CIT PET image and to investigate the usefulness of the method in differentiating healthy subjects from idiopathic Parkinson's disease (IPD) patients and the correlation of the value of functional volume parameters with the motor symptoms in patients with IPD. METHODS: Forty-three IPD patients and 23 age-matched healthy controls underwent F-18 FP-CIT PET. Using a dedicated workstation, VOIs for the whole striatum were drawn automatically with the gradient delineation method. The SUVmax, SUVmean, functional volume (FV), striatal volume activity (SVA), striatal-specific binding (SSB), and volume-specific uptake ratio (VSUR) were compared between the IPD patients and the normal subjects. In the IPD patients, the correlation between the clinical factor and the functional parameters was assessed. RESULTS: The SUVmax, SUVmean, FV, SVA, SSB, and VSUR were significantly lower in the IPD patients than in the normal subjects. In the receiver operating characteristic analysis, those parameters had significant and good-to-excellent accuracy. In the patients with IPD, a moderate negative correlation was revealed between the SUVmax and H&Y stage, the SUVmean and H&Y stage, SVA and H&Y stage, the VSUR and H&Y stage, the FV and bradykinesia, and the SVA and bradykinesia. CONCLUSION: The functional volumetric analysis of the striatum based on simple isocontour VOI was a useful method of analyzing the F-18 FP-CIT PET image. Not only can it be easily applied in daily clinical practice, but it can also be used as a clinical parameter to discriminate IPD and to correlate it with the disease severity.


Assuntos
Neostriado/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Tropanos , Idoso , Transporte Biológico , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neostriado/metabolismo , Doença de Parkinson/metabolismo , Estudos Retrospectivos
14.
Breast Cancer Res Treat ; 145(1): 137-42, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24682676

RESUMO

The aim of this study was to evaluate the clinical impact of the preoperative ¹8F-FDG PET/CT in the initial workup of breast cancer with clinically negative axillary nodes. Whether the status of the clinical axillary nodal involvement can be considered a parameter for making a decision to omit the preoperative ¹8F-FDG PET/CT in the situation reported herein was also determined. A total of 178 patients who had newly diagnosed breast cancer and for whom the conventional diagnostic modalities showed no sign of axillary node metastasis were retrospectively enrolled in this study. All the patients underwent preoperative ¹8F-FDG PET/CT. The images and histologic results that were obtained were analyzed. ¹8F-FDG PET/CT detected primary lesions in 156 of the 178 patients, with an overall sensitivity of 87.6 %, and false negative results were obtained for 22 patients (12.4 %). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of ¹8F-FDG PET/CT in the detection of axillary nodes were 20.8, 86.9, 37.0, 74.8, and 69.1 %, respectively. Extra-axillary node metastasis was identified in two patients (1.1 %) who had internal mammary nodes. There was no distant metastasis, but coexisting primary tumor was detected in five patients (2.8 %). In total, the therapeutic plan was changed based on ¹8F-FDG PET/CT in seven (3.9 %) of the 178 patients, but considering only the cases confined to breast cancer, the change occurred in only two patients (1.1 %). ¹8F-FDG PET/CT almost did not affect the initial staging and treatment plan in breast cancer with clinically negative axillary node. If the axillary node is clinically negative in the preoperative workup of breast cancer, then ¹8F-FDG PET/CT can be omitted.


Assuntos
Neoplasias da Mama/patologia , Carcinoma/patologia , Estadiamento de Neoplasias/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluordesoxiglucose F18 , Humanos , Pessoa de Meia-Idade , Imagem Multimodal , Compostos Radiofarmacêuticos
15.
Psychiatry Res ; 203(2-3): 201-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22980226

RESUMO

Mild cognitive impairment (MCI) is a heterogeneous condition associated with increased risk of Alzheimer's disease (AD) and other dementias. This study aimed to identify areas of initial hypoperfusion in MCI conversion to AD using technetium (Tc-99m) hexamethylpropyleneamine oxime (TC-99m HMPAO) single photon emission computed tomography (SPECT) to compare baseline cerebral hypoperfusion in converted MCI and non-converted MCI patients and normal controls. Forty-nine MCI patients were recruited for brain magnetic resonance imaging (MRI), detailed neuropsychological testing, Tc-99m HMPAO SPECT, and 1- to 2-year periodic follow-up to monitor progression to dementia status. We processed SPECT images with Statistical Parametric Mapping 8 (SPM8) software and performed voxel-based statistical parametric mapping analysis. Thirty-nine of 49 MCI patients were included in our analysis. Nine patients were diagnosed with conversion to AD, on average 19.0±6.6 months after initial assessment. Compared with normal controls, converted MCI patients demonstrated perfusion deficits in both parahippocampal gyri and right precuneus, and non-converted MCI patients demonstrated hypoperfusion in the left parahippocampal gyrus. Compared with non-converted MCI patients, converted MCI patients demonstrated significant hypoperfusion in both cingulate gyri and right precuneus. Our study suggests that using brain SPECT to identify initial hypoperfusion in patients with MCI may be helpful for predicting MCI patients likely to develop AD.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Tomografia Computadorizada de Emissão de Fóton Único , Isquemia Encefálica/diagnóstico por imagem , Cerebelo/irrigação sanguínea , Cerebelo/diagnóstico por imagem , Progressão da Doença , Dominância Cerebral/fisiologia , Seguimentos , Giro do Cíngulo/irrigação sanguínea , Giro do Cíngulo/diagnóstico por imagem , Humanos , Testes Neuropsicológicos , Giro Para-Hipocampal/irrigação sanguínea , Giro Para-Hipocampal/diagnóstico por imagem , Lobo Parietal/irrigação sanguínea , Lobo Parietal/diagnóstico por imagem , Valor Preditivo dos Testes , Valores de Referência , Fluxo Sanguíneo Regional/fisiologia , Tecnécio Tc 99m Exametazima
16.
Ann Nucl Med ; 26(8): 656-64, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22777857

RESUMO

PURPOSE: Statistical analysis of brain perfusion SPECT images has shown mild to severe abnormalities, consistent with cortical dysfunctions in the brain. Recently, functional brain imaging such as fMRI, PET and SPECT is increasingly used for diagnosis of MCI. In this study, we calculate the correlation with perfusion of brain SPECT and neuropsychological test scores of patients by SPM analysis to evaluate the relationship with cerebral hypoperfusion and cognitive dysfunction in MCI patients. Anatomical labeling was performed automatically using the Talairach Daemon (TD) and xjView. METHODS: Ninety-three patients (mean age 67.2 ± 7.42 years; 59 women and 34 men) with MCI were selected and examined by the comprehensive neuropsychological test. Tc-99m-HMPAO brain SPECT images were acquired on the patients using a two-head gamma camera. We analyzed the brain image of MCI patients by SPM8 software, and observed the anatomical correlated region, between the neuropsychological tests and cerebral hypoperfusion. The SPM8 tool provided correlation between neuropsychological score and brain perfusion by simple regression method. The neuropsychological test included attention, language function, visuospatial function, memory, frontal executive function, depression score and general cognitive function. RESULTS: Percentage of voxels with correlated area to the whole brain was calculated and the values by Rey complex figure test (CFT) copy score, MMSE score, Seoul verbal learning test (SVLT) immediate recall score and Rey CFT delayed recall score were 15.3, 12.33, 10.59 and 8.45 %, respectively. Rey CFT copy score was correlated with perfusion in the left middle temporal gyrus (BA 21), right inferior frontal gyrus (BA 45), right lingual gyrus, left lingual gyrus (BA 18), right postcentral gyrus (BA 40), right cingulate gyrus (BA 31) and left thalamus (pulvinar) with p < 0.01 FDR. The correlation related to MMSE included left parahippocampal gyrus, right fusiform gyrus and right middle frontal gyrus (BA 46). SVLT immediate recall score was correlated with left superior temporal gyrus and Rey CFT delayed recall score was correlated with left inferior frontal gyrus (BA 47), right inferior frontal gyrus, and left lentiform nucleus. Visuospatial and general cognitive dysfunctions in the patients with MCI were most correlated with cerebral hypoperfusion. CONCLUSIONS: Rey CFT copy and MMSE scores were more strongly correlated with blood perfusion of the brain than with other neuropsychological test scores. xjView was a useful tool to find out the anatomical name of the selected voxel or clusters and to display the cluster's anatomical information and list all cluster information and could be used instead of TD Client.


Assuntos
Circulação Cerebrovascular , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Testes Neuropsicológicos , Fluxo Sanguíneo Regional , Software , Idoso , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Feminino , Humanos , Masculino , Tecnécio Tc 99m Exametazima , Tomografia Computadorizada de Emissão de Fóton Único
17.
Nucl Med Commun ; 33(8): 848-58, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22692580

RESUMO

PURPOSE: The regions of significant correlation between cerebral hypoperfusion and neuropsychological assessment scores were evaluated using (99m)Tc-HMPAO SPECT in patients with mild cognitive impairment (MCI) on the basis of its three subtypes, namely, single-domain amnestic MCI (aMCI-s), multiple-domain amnestic MCI (aMCI-m), and nonamnestic MCI (naMCI), following which comparisons were made among the three subtypes of MCI. METHODS: Regions of hypoperfusion were determined by comparing the three groups with the normal group. Neuropsychological assessment included tests to evaluate attention, language and related functions, visuospatial function, memory, frontal-executive function, and mini-mental state examination and depression scores. Regions of cerebral hypoperfusion were identified by comparing the three groups of MCI patients with the normal group (P<0.05, uncorrected). One-way analysis of variance was used to examine differences across groups, and post-hoc a-priori pairwise comparisons were used for between-group analyses. The regions of significant correlation, related to the neuropsychological assessment scores, were identified by simple regression of SPM8 within the masking image of the area of cerebral hypoperfusion (P<0.05, uncorrected). RESULTS: The regions of cerebral hypoperfusion were identified by comparing members of the normal group with patients with aMCI-s, aMCI-m, and naMCI. The patients with aMCI-m showed significant correlation with all neuropsychological assessment scores, but the patients with aMCI-s correlated with four neuropsychological assessment scores of attention. The patients with naMCI revealed no significantly correlated regions (P<0.05, uncorrected). The regions that correlated with neuropsychological assessment scores in patients with aMCI-s were very small compared with those in patients with aMCI-m. The correlated regions in patients with aMCI-m were restricted to the left cerebrum and cerebellum. Brain areas showed significant correlation between neuropsychological assessment scores and hypoperfusion, which was evaluated by simple regression with the threshold being P less than 0.05, uncorrected. Rey complex figure test 20 min delayed, Korean-color word stroop test word reading, and Korean mini-mental state examination scores correlated more strongly with cerebral hypoperfusion compared with other assessment scores. CONCLUSION: The specific pattern of significant correlation of cerebral hypoperfusion with neuropsychological assessment scores was classified into three subtypes (aMCI-s, aMCI-m, and naMCI) according to the patients' deficits in their cognitive domains.


Assuntos
Amnésia/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Idoso , Amnésia/fisiopatologia , Encéfalo/fisiopatologia , Estudos de Casos e Controles , Disfunção Cognitiva/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Exametazima , Tomografia Computadorizada de Emissão de Fóton Único/métodos
18.
Nucl Med Mol Imaging ; 46(3): 223-6, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24900065

RESUMO

Cardiac hemangiomas are extremely rare, benign tumors, which can occur anywhere in the heart. Symptoms are variable according to the size, extension and tumor location, but most cases are asymptomatic and are detected incidentally. They may grow, remain stable and regress; therefore, the natural course of the tumors is unpredictable. Diagnosis mainly depends upon echocardiography, CT, MRI and angiography. Reports of detection by F-18 FDG PET/CT are very limited. We report a case of cardiac hemangioma attached to the right ventricle, compressing the ventricle. It was revealed incidentally on F-18 FDG PET/CT for routine evaluation of thyroid cancer. During two serial F-18 FDG PET/CTs, it grew from 2.8 cm to 4.0 cm with mild FDG uptake. After surgery, the patient remained stable without any complications.

19.
Ann Nucl Med ; 26(2): 164-74, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22042522

RESUMO

OBJECTIVES: We assign the anatomical names of functional activation regions in the brain, based on the probabilistic cyto-architectonic atlas by Anatomy 1.7 from an analysis of correlations between regional cerebral blood flow (rCBF) and clinical parameters of the non-demented Parkinson's disease (PD) patients by SPM8. We evaluated Anatomy 1.7 of SPM toolbox compared to 'Talairach Daemon' (TD) Client 2.4.2 software. METHODS: One hundred and thirty-six patients (mean age 60.0 ± 9.09 years; 73 women and 63 men) with non-demented PD were selected. Tc-99m-HMPAO brain single-photon emission computed tomography (SPECT) scans were performed on the patients using a two-head gamma-camera. We analyzed the brain image of PD patients by SPM8 and found the anatomical names of correlated regions of rCBF perfusion with the clinical parameters using TD Client 2.4.2 and Anatomy 1.7. The SPM8 provided a correlation coefficient between clinical parameters and cerebral hypoperfusion by a simple regression method. To the clinical parameters were added age, duration of disease, education period, Hoehn and Yahr (H&Y) stage and Korean mini-mental state examination (K-MMSE) score. RESULTS: Age was correlated with cerebral perfusion in the Brodmann area (BA) 6 and BA 3b assigned by Anatomy 1.7 and BA 6 and pyramis in gray matter by TD Client 2.4.2 with p < 0.001 uncorrected. Also, assigned significant correlated regions were found in the left and right lobules VI (Hem) with duration of disease, in left and right lobules VIIa crus I (Hem) with education, in left insula (Ig2), left and right lobules VI (Hem) with H&Y, and in BA 4a and 6 with K-MMSE score with p < 0.05 uncorrected by Anatomy 1.7, respectively. Most areas of correlation were overlapped by two different anatomical labeling methods, but some correlation areas were found with different names. CONCLUSION: Age was the most significantly correlated clinical parameter with rCBF. TD Client found the exact anatomical name by the peak intensity position of the cluster while Anatomy 1.7 of SPM8 toolbox, using the cyto-architectonic probability maps, assigned the anatomical name by percentage value of the probability.


Assuntos
Circulação Cerebrovascular , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/fisiopatologia , Software , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Idoso , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/patologia , Compostos Radiofarmacêuticos , Tecnécio Tc 99m Exametazima , Tomografia Computadorizada de Emissão de Fóton Único/métodos
20.
J Microbiol Biotechnol ; 17(11): 1818-25, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18092466

RESUMO

S-Adenosylmethionine (SAM) was previously documented to activate secondary metabolism in a variety of Streptomyces spp. and to promote actinorhodin (ACT) and undecylprodigiosin (RED) in Streptomyces coelicolor. The SAM-induced proteins in S. coelicolor include several ABC transporter components (SCO5260 and SCO5477) including BldKB, the component of a well-known regulatory factor for differentiations. In order to assess the role of these ABC transporter complexes in differentiation of Streptomyces, SCO5260 and SCO5476, the first genes from the cognate complex clusters, were individually inactivated by gene replacement. Inactivation of either SCO5260 or SCO5476 led to impaired sporulation on agar medium, with the more drastic defect in the SCO5260 null mutant (ASCO5260). ASCO5260 displayed growth retardation and reduced yields of ACT and RED in liquid cultures. In addition, SAM supplementation failed in promoting the production of ACT and RED in ASCO5260. Inactivation of SCO5476 gave no significant change in growth and production of ACT and RED, but impaired the promoting effect of SAM on ACT production without interfering with the effect on RED production. The present study suggests that SAM induces several ABC transporters to modulate secondary metabolism and morphological development in S. coelicolor.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/fisiologia , S-Adenosilmetionina/farmacologia , Streptomyces coelicolor/fisiologia , Esporos Bacterianos/fisiologia
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