Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
Clin Nucl Med ; 49(1): 104-105, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37976532

RESUMEN

ABSTRACT: A 79-year-old man with nasopharyngeal cancer (NPC) presented with diplopia symptom and a history of diabetes mellitus was referred for an FDG PET/CT scan to determine the pretreatment staging. The FDG PET/CT scan revealed NPC with skull base invasion and decreased FDG uptake at the left striatum. A review of his clinical history and a brain MRI conducted 5 months ago confirmed a previous diagnosis of left hyperglycemic hemichorea. In this NPC patient with inadequate blood sugar control, unilateral striatum hypometabolism may persist for up to 5 months after the initial clinical symptoms.


Asunto(s)
Neoplasias Nasofaríngeas , Tomografía Computarizada por Tomografía de Emisión de Positrones , Anciano , Humanos , Masculino , Fluorodesoxiglucosa F18 , Carcinoma Nasofaríngeo/diagnóstico por imagen , Neoplasias Nasofaríngeas/complicaciones , Neoplasias Nasofaríngeas/diagnóstico por imagen , Tomografía de Emisión de Positrones , Radiofármacos
2.
Artículo en Inglés | MEDLINE | ID: mdl-38083702

RESUMEN

CT scanning of the chest is one the most important imaging modalities available for pulmonary disease diagnosis. Lung segmentation plays a crucial step in the pipeline of computer-aided analysis and diagnosis. As deep learning models have achieved human-level accuracy in semantic segmentation of anatomical structures, we propose to use trained deep learning models to predict both healthy and infectious areas in chest CT slices. The semantic segmentation results are summarized and visualized using volume rendering technology in the form of roadmaps. The roadmaps consist of both location and volume information that can be used as a location guidance for inspecting suspected pulmonary lesions of chest CT and can possibly be combined into a rapid triage algorithm for treating acute pulmonary diseases.Clinical Relevance- This research applied trained semantic segmentation models in identifying normal lung and pneumonic infection areas to generate a roadmap for assisting medical doctors in browsing chest CT and prognostication.


Asunto(s)
Neumonía , Humanos , Neumonía/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Pulmón/patología , Tórax , Algoritmos
3.
Environ Health Prev Med ; 25(1): 68, 2020 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-33153431

RESUMEN

BACKGROUND: Particulate matter (PM) < 2.5 µm (PM2.5) or fine PM is a serious public health concern. It affects DNA methylation and heightens carcinogenesis. Deleted in lung and esophageal cancer 1 (DLEC1) is a tumor suppressor gene. However, aberrant methylation of the gene is associated with several cancers. We evaluated the association between PM2.5 and DLEC1 promoter methylation in Taiwanese adults based on regular outdoor exercise. METHODS: We obtained DNA methylation and exercise data of 496 participants (aged between 30 and 70 years) from the Taiwan Biobank (TWB) database. We also extracted PM2.5 data from the Air Quality Monitoring Database (AQMD) and estimated participants' exposure using residential addresses. RESULTS: DLEC1 methylation and PM2.5 were positively associated: beta coefficient (ß) = 0.114 × 10-3; p value = 0.046. The test for interaction between exercise and PM2.5 on DLEC1 methylation was significant (p value = 0.036). After stratification by exercise habits, PM2.5 and DLEC1 methylation remained significantly associated only among those who exercised regularly (ß = 0.237 × 10-3; p value = 0.007). PM2.5 quartile-stratified analyses revealed an inverse association between regular exercise and DLEC1 methylation at PM2.5 < 27.37 µg/m3 (ß = - 5.280 × 10-3; p value = 0.009). After combining exercise habits and PM2.5 quartiles, one stratum (i.e., regular exercise and PM2.5 < 27.37 µg/m3) was inversely associated with DLEC1 methylation (ß = -5.160 × 10-3, p value = 0.007). CONCLUSIONS: We found significant positive associations between PM2.5 and DLEC1 promoter methylation. Regular exercise at PM2.5 < 27.37 µg/m3 seemingly regulated DLEC1 promoter methylation.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Metilación de ADN/efectos de los fármacos , Exposición a Riesgos Ambientales/efectos adversos , Ejercicio Físico , Material Particulado/efectos adversos , Proteínas Supresoras de Tumor/metabolismo , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Taiwán
4.
Clin Epigenetics ; 12(1): 117, 2020 07 31.
Artículo en Inglés | MEDLINE | ID: mdl-32736658

RESUMEN

BACKGROUND: Polycyclic aromatic hydrocarbon (PAH)-rich substances like cigarette smoke and PM2.5 induce aryl hydrocarbon receptor (AHR)-mediated aryl hydrocarbon receptor repressor (AHRR) methylation. AHRR cg05575921 and coagulation factor II (thrombin) receptor-like 3 (F2RL3) cg03636183 methylation patterns are well-established biomarkers for smoking. Even though AHRR cg05575921 methylation has recently been associated with PM2.5, the interaction between smoking and PM2.5 on AHRR methylation is yet to be fully explored. We evaluated AHRR and F2RL3 CpG sites to identify potential significant markers in relation to PM2.5 and smoking in Taiwanese adults. METHODS: DNA methylation and smoking data of 948 participants aged 30-70 years were obtained from the Taiwan Biobank Database (2008-2015), while PM2.5 data were obtained from the Air Quality Monitoring Database (2006-2011). RESULTS: Smoking and PM2.5 were independently associated with hypomethylation (lower levels) of AHRR cg05575921, AHRR cg23576855, F2RL3 cg03636183, and F2LR3 cg21911711 after multiple-comparison correction (Bonferroni P < 0.00028409). Cg05575921 was the most hypomethylated AHRR CpG site, while cg03636183 was the most hypomethylated F2RL3 CpG site. Overall, cg05575921 was the most hypomethylated CpG site: ß = - 0.03909, P < 0.0001; - 0.17536, P < 0.0001 for former and current smoking, respectively (P-trendsmoking < 0.0001) and - 0.00141, P < 0.0001 for PM2.5. After adjusting for F2RL3 cg03636183, smoking and PM2.5 remained significantly associated with cg05575921 hypomethylation: ß - 0.02221, P < 0.0001; - 0.11578, P < 0.0001 for former and current smoking, respectively (P-trendsmoking < 0.0001) and - 0.0070, P = 0.0120 for PM2.5. After stratification by sex, smoking and PM2.5 remained associated (P < 0.05) with cg05575921 hypomethylation in both men (ß = - 0.04274, - 0.17700, and - 0.00163 for former smoking, current smoking, and PM2.5, respectively) and women (ß = - 0.01937, - 0.17255, and - 0.00105 for former smoking, current smoking, and PM2.5, respectively). After stratification by residential area, former and current smoking remained associated (P < 0.05) with cg05575921 hypomethylation: ß = - 0.03918 and - 0.17536, respectively (P-trendsmoking < 0.0001). Living in the central and southern areas was also associated (P < 0.05) with cg05575921 hypomethylation: ß = - 0.01356 and - 0.01970, respectively (P-trendarea < 0.0001). CONCLUSION: Smoking and PM2.5 were independently associated with hypomethylation of cg05575921, cg23576855, cg03636183, and cg21911711. The most hypomethylated CpG site was cg05575921 and its association with smoking and PM2.5 was dose-dependent.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Metilación de ADN/genética , Material Particulado/metabolismo , Proteínas Represoras/genética , Fumar/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteínas Represoras/metabolismo , Fumar/metabolismo , Taiwán
5.
Front Pediatr ; 8: 120, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32318523

RESUMEN

Background: Neonatal necrotizing enterocolitis (NEC) is a complex and lethal inflammatory bowel necrosis that primarily affects premature infants. Gut dysbiosis has been implicated in the pathogenesis of NEC. We aim to assess the association between NEC and two other diseases in children, including allergic diseases and constipation, considered to be associated with the alterations in gut microbiota composition. Methods: This retrospective population-based cohort study was conducted using the Taiwan Birth Registration Database, Birth Certificate Application, and National Health Insurance Research Database to inter-link the medical claims of neonates and their mothers. A total of 2,650,634 delivery events were retrieved from 2005 to 2015. We identified a NEC cohort and selected a comparison cohort according to propensity score matching (1:1). Cox proportional hazard regression models were used to determine possible associations of predictors and to obtain adjusted hazard ratios (aHRs). Results: A total of 1,145 subjects in the NEC cohort and 1,145 subjects in the matched cohort were analyzed during the observation period. No significant difference was observed in the incidence of allergic diseases between the two groups. NEC patients had a significant 30.7% increased risk of developing constipation (aHR = 1.307; 95% CI 1.089-1.568). The cumulative incidence of constipation was significantly higher in the NEC cohort than in the matched cohort by the end of follow-up (log-rank test P = 0.003). Conclusion: Infants with NEC have a significantly higher incidence rate of developing constipation and FTT but no increased risk of allergic diseases.

7.
J Healthc Eng ; 2018: 2908517, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29849996

RESUMEN

Automatic image segmentation and feature analysis can assist doctors in the treatment and diagnosis of diseases more accurately. Automatic medical image segmentation is difficult due to the varying image quality among equipment. In this paper, the automatic method employed image multiscale intensity texture analysis and segmentation to solve this problem. In this paper, firstly, SVM is applied to identify common pneumothorax. Features are extracted from lung images with the LBP (local binary pattern). Then, classification of pneumothorax is determined by SVM. Secondly, the proposed automatic pneumothorax detection method is based on multiscale intensity texture segmentation by removing the background and noises in chest images for segmenting abnormal lung regions. The segmentation of abnormal regions is used for texture transformed from computing multiple overlapping blocks. The rib boundaries are identified with Sobel edge detection. Finally, in obtaining a complete disease region, the rib boundary is filled up and located between the abnormal regions.


Asunto(s)
Neumotórax/diagnóstico por imagen , Máquina de Vectores de Soporte , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Femenino , Humanos , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Adulto Joven
8.
PLoS One ; 12(7): e0175836, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28704397

RESUMEN

OBJECTIVE: To investigate whether Sjogren's syndrome would have an influence on the development of Parkinson's disease. METHODS: A population-based case-control study was conducted. Participants consisted of 7716 subjects with newly diagnosed Parkinson's disease and a population of 75129 matched control subjects between 2000 and 2010. We measured the risk of Parkinson's disease in association with Sjogren's syndrome by using adjusted odds ratios. RESULTS: A total of 143 Parkinson's disease subjects (1.9%) and 893 control subjects (1.2%) suffered from Sjogren's syndrome (p < 0.001). The crude odds ratio for Parkinson's disease among subjects with Sjogren's syndrome was 1.56 (95% CI 1.30-1.86; p < 0.01). After adjustment for potential confounders which have been proposed that would increase the risk of development of Parkinson's disease, Sjogren's syndrome was found to be significantly associated with the risk of Parkinson's disease with an odds ratio of 1.37 (95% CI 1.15-1.65; p < 0.01). CONCLUSION: This study preliminarily proposed that Sjogren's syndrome was significant associated with an increased risk of Parkinson's disease.


Asunto(s)
Enfermedad de Parkinson/epidemiología , Síndrome de Sjögren/epidemiología , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Oportunidad Relativa , Factores de Riesgo , Síndrome de Sjögren/complicaciones , Taiwán/epidemiología
9.
Can Assoc Radiol J ; 67(2): 190-201, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26831732

RESUMEN

PURPOSE: The study sought to evaluate the efficacy of magnetic resonance imaging (MRI) in patients with suspected subclavian steal syndrome (SSS) using both contrast-enhanced (CE) MR angiography and phase-contrast (PC) MRI. METHODS: Fifteen suspected SSSs from 13 patients were evaluated using CE-MR angiography and PC-MRI. Ten patients also received dynamic CE-MR angiography. RESULTS: All MRI examinations were technically successful. By combining CE-MR angiography with PC-MRI, 10 SSSs were diagnosed in 9 patients. The delay enhancement dynamic technique predicted SSS with a sensitivity, specificity, and accuracy of 57.1%, 100%, and 72.7%, respectively. Without the dynamic technique, affected delay-enhanced arteries were poorly visualized and could be mistaken for occluded vessels. Retrograde vertebral flow by PC-MRI was used to predict ipsilateral SSS with a sensitivity, specificity, and accuracy of 100%, 60%, and 86.7%, respectively. There were 2 false positives including 1 patient with a proximal total occlusion of the affected vertebral artery and another with brachiocephalic steal syndrome rather than SSS. This suggested that retrograde vertebral flow does not always indicate SSS. CONCLUSIONS: CE-MR angiography combined with PC-MRI is efficacious when evaluating SSS in clinical practice.


Asunto(s)
Medios de Contraste , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Síndrome del Robo de la Subclavia/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Angiografía por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Síndrome del Robo de la Subclavia/patología , Adulto Joven
10.
J Med Biol Eng ; 35(6): 724-734, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26692830

RESUMEN

Parkinson's disease is a progressive neurodegenerative disorder that has a higher probability of occurrence in middle-aged and older adults than in the young. With the use of a computer-aided diagnosis (CAD) system, abnormal cell regions can be identified, and this identification can help medical personnel to evaluate the chance of disease. This study proposes a hierarchical correlation histogram analysis based on the grayscale distribution degree of pixel intensity by constructing a correlation histogram, that can improves the adaptive contrast enhancement for specific objects. The proposed method produces significant results during contrast enhancement preprocessing and facilitates subsequent CAD processes, thereby reducing recognition time and improving accuracy. The experimental results show that the proposed method is superior to existing methods by using two estimation image quantitative methods of PSNR and average gradient values. Furthermore, the edge information pertaining to specific cells can effectively increase the accuracy of the results.

11.
Int J Biomed Imaging ; 2014: 947539, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25610453

RESUMEN

We propose an ischemic stroke detection system with a computer-aided diagnostic ability using a four-step unsupervised feature perception enhancement method. In the first step, known as preprocessing, we use a cubic curve contrast enhancement method to enhance image contrast. In the second step, we use a series of methods to extract the brain tissue image area identified during preprocessing. To detect abnormal regions in the brain images, we propose using an unsupervised region growing algorithm to segment the brain tissue area. The brain is centered on a horizontal line and the white matter of the brain's inner ring is split into eight regions. In the third step, we use a coinciding regional location method to find the hybrid area of locations where a stroke may have occurred in each cerebral hemisphere. Finally, we make corrections and mark the stroke area with red color. In the experiment, we tested the system on 90 computed tomography (CT) images from 26 patients, and, with the assistance of two radiologists, we proved that our proposed system has computer-aided diagnostic capabilities. Our results show an increased stroke diagnosis sensitivity of 83% in comparison to 31% when radiologists use conventional diagnostic images.

12.
J Chin Med Assoc ; 76(8): 458-65, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23769881

RESUMEN

BACKGROUND: Time-of-flight (TOF) magnetic resonance (MR) angiography is based on flow-related enhancement using the T1-weighted spoiled gradient echo, or the fast low-angle shot gradient echo sequence. However, materials with short T1 relaxation times may show hyperintensity signals and contaminate the TOF images. The objective of our study was to determine whether subtraction three-dimensional (3D) TOF MR angiography improves image quality in brain and temporal bone diseases with unwanted contaminations with short T1 relaxation times. METHODS: During the 12-month study period, patients who had masses with short T1 relaxation times noted on precontrast T1-weighted brain MR images and 24 healthy volunteers were scanned using conventional and subtraction 3D TOF MR angiography. The qualitative evaluation of each MR angiogram was based on signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and scores in three categories, namely, (1) presence of misregistration artifacts, (2) ability to display arterial anatomy selectively (without contamination by materials with short T1 relaxation times), and (3) arterial flow-related enhancement. RESULTS: We included 12 patients with intracranial hematomas, brain tumors, or middle-ear cholesterol granulomas. Subtraction 3D TOF MR angiography yielded higher CNRs between the area of the basilar artery (BA) and normal-appearing parenchyma of the brain and lower SNRs in the area of the BA compared with the conventional technique (147.7 ± 77.6 vs. 130.6 ± 54.2, p < 0.003 and 162.5 ± 79.9 vs. 194.3 ± 62.3, p < 0.001, respectively) in all 36 cases. The 3D subtraction angiography did not deteriorate image quality with misregistration artifacts and showed a better selective display of arteries (p < 0.0001) and arterial flow-related enhancement (p < 0.044) than the conventional method. CONCLUSION: Subtraction 3D TOF MR angiography is more appropriate than the conventional method in improving the image quality in brain and temporal bone diseases with unwanted contaminations with short T1 relaxation times.


Asunto(s)
Enfermedades Óseas/diagnóstico , Encefalopatías/diagnóstico , Imagenología Tridimensional/métodos , Angiografía por Resonancia Magnética/métodos , Hueso Temporal , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Imagenología Tridimensional/normas , Lactante , Angiografía por Resonancia Magnética/normas , Masculino , Persona de Mediana Edad
13.
Health Phys ; 104(5 Suppl 2): S60-7, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23528275

RESUMEN

The use of surveyed data on the x-ray tube workloads and clinical exposure parameters was suggested in NCRP Report No. 147 for the structural shielding design of medical x-ray installations. To guide the shielding design of radiographic x-ray rooms in Taiwan, a large-scale survey was conducted to collect information required for the computations of the transmissions from broad x-ray beams through shielding materials. Surveyed data were collected during one week from 10,750 projections of 6,657 examinations in 13 radiographic rooms from nine hospitals. This survey was the first time that this type of clinical data has been collected in Taiwan on a large scale. The surveyed total workload was divided into separate contributions from x-ray projections directed at the floor, the wall bucky, and all barriers (used for secondary barriers). Based on the surveyed workload distributions, the unshielded air kerma per patient at 1 m from the source was calculated by the PCXMC program using surveyed x-ray tube parameters on the generator waveform, anode material, target angle, and filtration. Subsequently, the transmissions of x-rays through different barrier materials were computed by considering the average workloads and the average workloads plus one standard deviations. The latter computations were for a sensitivity study to find the influence of workload variations in different hospitals on the shielding requirements. All surveyed data and calculated results were compared with corresponding values given in NCRP 147 to analyze the radiographic imaging differences between Taiwan and U.S.


Asunto(s)
Modelos Teóricos , Protección Radiológica/métodos , Radiografía/instrumentación , Servicio de Radiología en Hospital , Tecnología Radiológica , Humanos , Exposición Profesional , Dispersión de Radiación , Taiwán , Carga de Trabajo , Rayos X
14.
J Exp Med ; 206(5): 1181-99, 2009 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-19414555

RESUMEN

Neutrophils, the major phagocytes that form the first line of cell-mediated defense against microbial infection, are produced in the bone marrow and released into the circulation in response to granulocyte-colony stimulating factor (G-CSF). Here, we report that androgen receptor knockout (ARKO) mice are neutropenic and susceptible to acute bacterial infection, whereas castration only results in moderate neutrophil reduction in mice and humans. Androgen supplement can restore neutrophil counts via stabilizing AR in castrated mice, but not in ARKO and testicular feminization mutant (Tfm) mice. Our results show that deletion of the AR gene does not influence myeloid lineage commitment, but significantly reduces the proliferative activity of neutrophil precursors and retards neutrophil maturation. CXCR2-dependent migration is also decreased in ARKO neutrophils as compared with wild-type controls. G-CSF is unable to delay apoptosis in ARKO neutrophils, and ARKO mice show a poor granulopoietic response to exogenous G-CSF injection. In addition, AR can restore G-CSF-dependent granulocytic differentiation upon transduction into ARKO progenitors. We further found that AR augments G-CSF signaling by activating extracellular signal-regulated kinase 1/2 and also by sustaining Stat3 activity via diminishing the inhibitory binding of PIAS3 to Stat3. Collectively, our findings demonstrate an essential role for AR in granulopoiesis and host defense against microbial infection.


Asunto(s)
Infecciones Bacterianas/genética , Neutropenia/etiología , Neutropenia/microbiología , Receptores Androgénicos/deficiencia , Animales , Infecciones Bacterianas/prevención & control , Diferenciación Celular , Cartilla de ADN , Granulocitos/citología , Granulocitos/microbiología , Granulocitos/fisiología , Infertilidad Masculina/genética , Masculino , Ratones , Ratones Noqueados , Receptores Androgénicos/genética , Receptores Androgénicos/fisiología , Transcripción Genética
15.
Anal Chem ; 78(15): 5316-21, 2006 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-16878865

RESUMEN

A four-channel multiplexed electrospray capillary electrophoresis interface has been developed. This new interface permits up to four capillary electrophoresis columns to be sampled sequentially by means of a stepper motor and a notched rotating plate assembly, which at any instant occludes all but a single sprayer. In this design, four sheath liquid electrospray probes are oriented in a circular array situated 90 degrees relative to one another. The rotating metal disk, which contains a one-quarter notch, is mounted to the stepper motor assembly and is located between the sprayers and the entrance aperture of an ion trap mass spectrometer. By using the data acquisition signal from the ion trap mass spectrometer, the scan event is synchronized with the rotation of the metal disk. With this device, four discrete sample streams can be simultaneously analyzed, resulting in a 4-fold increase in analytical throughput.


Asunto(s)
Espectrometría de Masa por Ionización de Electrospray/instrumentación , Electroforesis Capilar/instrumentación , Electroforesis Capilar/métodos , Diseño de Equipo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría de Masa por Ionización de Electrospray/métodos , Propiedades de Superficie , Factores de Tiempo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA