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1.
Zhonghua Jie He He Hu Xi Za Zhi ; 46(1): 27-33, 2023 Jan 12.
Artículo en Chino | MEDLINE | ID: mdl-36617925

RESUMEN

Objective: To investigate the bronchoscopy resource allocation and technology application in county-level hospitals in China. Methods: A cross-sectional survey was conducted. In 2021, 12 provinces were sampled from all provinces in China according to the regional Gross Domestic Product (GDP) and the number of counties, in which a total of 291 county-level hospitals were randomly enrolled. Two county-level hospitals which carried out bronchoscopy technology in each province were randomly sampled to investigate the status of bronchoscopy resources, technical application, decontamination and anesthesia by using questionnaires. Independent sample t test or two related sample nonparametric test were used for comparison between groups. Spearman correlation analysis was used to explore the correlation. Bilateral P<0.05 was considered statistically significant. Results: According to the sampling results, it was estimated that in the county-level hospitals, the proportion of those performing bronchoscopy was 11.4% (9.9%, 13.8%), which was significantly correlated with the population in the province (r=0.64, P=0.025) and the regional GDP (r=0.65, P=0.025).The 24 county-level hospitals interviewed were equipped with (1.6±1.0) bronchoscopes on average, and the number of hospitals with electronic bronchoscopes and fiberoptic bronchoscopes was 22 (91.7%) and 6 (25.0%), respectively. Six (25.0%) hospitals performed bronchoscopy every working day. Twelve (50.0%) hospitals had relatively permanent physicians and nurses. All operating doctors had received special training. There was a significant increase in the number of bronchoscopy cases per hospital in 2020 compared to 2019 [140(70, 335) vs. 100(29, 254), P=0.001]. All hospitals used standard cleaning and sterilization workbenches, cleaning agents and disinfectants. Surface anesthesia was available in 24 hospitals, and bronchoscopy techniques under sedation and analgesia were performed in 10 (41.7%) hospitals. Atropine was still used to prevent airway secretions in 2 (8.3%) hospitals,although not recommended by guidelines. Conclusions: There was a large gap between the current status of bronchoscopy technology in county-level hospitals and the standards of the National Health Commission, together with regional disparities. Bronchoscopist training in the standardization and the decontamination work met the requirements. In some hospitals, the use of complementary medicines was not standardized or the sedatives were not given routinely according to the guidelines. We should promote the popularization and standardization of bronchoscopy technology, and strengthen the allocation of related resources in China's county hospitals.


Asunto(s)
Broncoscopía , Hospitales de Condado , Humanos , Estudios Transversales , Encuestas y Cuestionarios , Hospitales , China
2.
Eur J Surg Oncol ; 43(1): 76-84, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27591937

RESUMEN

BACKGROUND: The necessity of routine sub-nipple biopsy was uncertain, and the role of preoperative magnetic resonance imaging (MRI) in detecting nipple invasion in patients who have been selected for nipple sparing mastectomy (NSM) has not been adequately evaluated. METHODS: We retrospectively collected and analyzed the medical and surgical records of 434 patients with primary operable breast cancer who met the criteria for NSM and underwent breast surgery during the period January 2011 to December 2015. Patients were stratified into three risk groups (low, intermediate, and high) according to tumor size and tumor-to-nipple distance. RESULTS: Among the 434 patients in this study, 29 (6.7%) had occult invasion of the nipple-areola complex (NAC). Sub-nipple biopsy had a sensitivity of 84.6%, a specificity of 100%, a false negative rate of 1.2%, a false positive rate of 0%, and an overall accuracy rate of 98.8% in confirming NAC invasion. The NAC invasion rate was 0% in the low-risk group, 5.1% in the intermediate-risk group, and 19.7% in the high-risk group (P < 0.01). The overall NPV of preoperative MRI for predicting NAC invasion was 94.8%. Cost analysis revealed that the cost of NSM with sub-nipple biopsy was significantly higher than that of NSM alone, with a mean difference in cost of USD 238.5 (P < 0.01). CONCLUSION: The high negative predictive value of MRI for NAC invasion is useful for selection of patients receiving NSM. Sub-nipple biopsy is a reliable procedure to detect occult NAC invasion, however, routine use is not cost-effect for low risk patients.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Imagen por Resonancia Magnética/métodos , Mastectomía/métodos , Biopsia , Neoplasias de la Mama/patología , Análisis Costo-Beneficio , Femenino , Humanos , Persona de Mediana Edad , Invasividad Neoplásica/diagnóstico por imagen , Invasividad Neoplásica/patología , Pezones , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Medición de Riesgo , Sensibilidad y Especificidad
3.
Br J Cancer ; 112(7): 1199-205, 2015 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-25756398

RESUMEN

BACKGROUND: Sunitinib is approved worldwide for treatment of advanced pancreatic neuroendocrine tumours (pNET), but no validated markers exist to predict response. This analysis explored biomarkers associated with sunitinib activity and clinical benefit in patients with pNET and carcinoid tumours in a phase II study. METHODS: Plasma was assessed for vascular endothelial growth factor (VEGF)-A, soluble VEGF receptor (sVEGFR)-2, sVEGFR-3, interleukin (IL)-8 (n=105), and stromal cell-derived factor (SDF)-1α (n=28). Pre-treatment levels were compared between tumour types and correlated with response, progression-free (PFS), and overall survival (OS). Changes in circulating myelomonocytic and endothelial cells were also analysed. RESULTS: Stromal cell-derived factor-1α and sVEGFR-2 levels were higher in pNET than in carcinoid (P=0.003 and 0.041, respectively). High (above-median) baseline SDF-1α was associated with worse PFS, OS, and response in pNET, and high sVEGFR-2 with longer OS (P⩽0.05). For carcinoid, high IL-8, sVEGFR-3, and SDF-1α were associated with shorter PFS and OS, and high IL-8 and SDF-1α with worse response (P⩽0.05). Among circulating cell types, monocytes showed the largest on-treatment decrease, particularly CD14+ monocytes co-expressing VEGFR-1 or CXCR4. CONCLUSIONS: Interleukin-8, sVEGFR-3, and SDF-1α were identified as predictors of sunitinib clinical outcome. Putative pro-tumorigenic CXCR4+ and VEGFR-1+ monocytes represent novel candidate markers and biologically relevant targets explaining the activity of sunitinib.


Asunto(s)
Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/sangre , Citocinas/sangre , Indoles/uso terapéutico , Monocitos/patología , Tumores Neuroendocrinos/sangre , Tumores Neuroendocrinos/tratamiento farmacológico , Pirroles/uso terapéutico , Biomarcadores de Tumor/inmunología , Tumor Carcinoide/sangre , Tumor Carcinoide/tratamiento farmacológico , Tumor Carcinoide/inmunología , Citocinas/inmunología , Supervivencia sin Enfermedad , Femenino , Humanos , Recuento de Leucocitos , Monocitos/inmunología , Tumores Neuroendocrinos/inmunología , Sunitinib , Resultado del Tratamiento
5.
Br J Radiol ; 85(1014): 778-83, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21828149

RESUMEN

OBJECTIVE: The aim of this study was to diagnose microvascular invasion in patients with solitary hepatocellular carcinoma (HCC) from pre-operative CT imaging. METHODS: 102 patients with solitary HCC who underwent curative hepatectomy were retrospectively included in our study. The pre-operative 3-phase CT imaging and laboratory data for the 102 patients were reviewed. Tumour size, tumour margin, peritumoral enhancement and α-fetoprotein level were assessed. Surgical pathology was reviewed; tumour differentiation, liver fibrosis score and microvascular invasion were recorded. RESULTS: The histopathological results revealed that 50 HCCs were positive and the other 52 were negative for microvascular invasion. Univariate analysis revealed that tumour size (p = 0.036), higher Edmondson-Steiner grade (p = 0.047) and non-smooth tumour margin (p < 0.001) showed statistically significant associations with microvascular invasion. Multivariate logistic regression analysis showed that non-smooth tumour margin had a statistically significant association with microvascular invasion only (p < 0.001). The sensitivity, specificity, positive predictive value and negative predictive value of the non-smooth tumour margin in the prediction of microvascular invasion were 66%, 86.5%, 82.5% and 72.6%, respectively. CONCLUSION: Non-smooth tumour margin in pre-operative CT had a statistically significant association with microvascular invasion. More aggressive treatment should be considered in HCC patients with suspected positive microvascular invasion.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Tomografía Computarizada por Rayos X , Neoplasias Vasculares/diagnóstico por imagen , Neoplasias Vasculares/patología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/cirugía , Femenino , Humanos , Neoplasias Hepáticas/cirugía , Masculino , Microvasos , Persona de Mediana Edad , Invasividad Neoplásica , Valor Predictivo de las Pruebas , Estudios Retrospectivos
6.
Br J Cancer ; 105(1): 112-7, 2011 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-21673679

RESUMEN

BACKGROUND: Circulating endothelial cells (CECs) are a candidate biomarker for monitoring angiogenesis in cancer. Circulating endothelial cell subsets are mobilised by angiogenic mediators. Because of the highly angiogenic phenotype of renal cell carcinoma (RCC), we sought to assess the potential of CECs as a marker of RCC in patients with von Hippel-Lindau (VHL) disease and those with sporadic RCC. METHODS: We performed multicolour flow cytometry to enumerate CECs in patients with RCC, patients with VHL disease with and without RCC, and normal subjects. Two subsets of CECs were evaluated: mature CECs (mCECs) and circulating endothelial progenitors (CEPs). RESULTS: In patients with VHL disease and RCC and those with sporadic RCC (N=10), CEPs and the CEP:mCEC ratio were higher than in normal subjects (N=17) (median CEPs: 0.97 vs 0.19 cells µl(-1), respectively, P<0.01; median CEP:mCEC: 0.92 vs 0.58, respectively, P=0.04). However, in patients with VHL without RCC, CECs were not increased. In paired pre- and post-nephrectomy RCC patient samples (N=20), CEPs decreased after surgery (median difference 0.02 cells µl(-1), -0.06 to 1.2; P=0.05). CONCLUSION: Circulating endothelial progenitors were elevated in RCC, but not in patients with VHL without RCC. Circulating endothelial progenitor enumeration merits further investigation as a monitoring strategy for patients with VHL.


Asunto(s)
Biomarcadores de Tumor/análisis , Carcinoma de Células Renales/patología , Células Endoteliales/patología , Movilización de Célula Madre Hematopoyética , Neoplasias Renales/patología , Células Madre Neoplásicas/patología , Enfermedad de von Hippel-Lindau/patología , Estudios de Casos y Controles , Humanos , Tasa de Supervivencia , Resultado del Tratamiento
7.
Oncogene ; 29(20): 2938-49, 2010 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-20208561

RESUMEN

Novel treatment approaches are needed for children with advanced neuroblastoma. Studies with neuroblastoma cells have indicated the presence of a hypoxia-driven vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR)-1 autocrine loop modulating hypoxia-inducible factor-1alpha (HIF-1alpha). Whether other receptor tyrosine kinases (RTKs) are capable of modulating HIF-1alpha levels and whether RTKs can regulate HIF-2alpha as well is largely unknown. We evaluated neuroblastoma cell lines for expression of various RTKs. Although cell lines were heterogeneous in the expression of VEGFR-1, -3, c-Kit and RET, most cells expressed PDGFR-alpha and -beta. Ligand-induced activation of multiple RTKs upregulated HIF-1alpha levels, whereas activation of VEGFR-1 alone upregulated HIF-2alpha. Multitargeted tyrosine kinase inhibitor sunitinib reduced hypoxia-induced rises in HIF-1alpha and HIF-2alpha through mechanisms involving effects on both mRNA levels and protein stability. In addition, sunitinib and sorafenib had direct effects on tumor cell viability in vitro. In a neuroblastoma xenograft model, tumor growth inhibition by sunitinib was associated with inhibition of angiogenesis and reduced HIF-1alpha levels. These findings show that multiple RTKs may regulate the HIF axis in normoxia and hypoxia and suggest that multikinase inhibitors may exert antiangiogenic effects not only by direct effects on endothelial cells, but also by blocking compensatory hypoxia- and ligand-induced changes in HIF-1alpha and HIF-2alpha.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Hipoxia/metabolismo , Neuroblastoma/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/antagonistas & inhibidores , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Western Blotting , Movimiento Celular , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/antagonistas & inhibidores , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Técnicas para Inmunoenzimas , Indoles/farmacología , Ratones , Ratones Endogámicos NOD , Ratones SCID , Neovascularización Patológica/prevención & control , Neuroblastoma/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-kit/genética , Proteínas Proto-Oncogénicas c-kit/metabolismo , Proteínas Proto-Oncogénicas c-ret/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-ret/metabolismo , Pirroles/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/farmacología , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Receptores de Interleucina-2/fisiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sunitinib , Receptor 1 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Receptor 3 de Factores de Crecimiento Endotelial Vascular/genética , Receptor 3 de Factores de Crecimiento Endotelial Vascular/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
8.
Eur J Surg Oncol ; 35(1): 21-4, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18640002

RESUMEN

BACKGROUND: The purpose of this study was to determine the accuracy of core needle biopsy (CNB) diagnoses of papillary breast lesions, and to identify the risk factors and histologic features, compared with excisional biopsy (EB). METHOD: We retrospectively reviewed 1,682 sonographically guided core needle biopsies performed at one single medical center from January 2001 through December 2005, and identified 41 papillary lesions. Surgical correlation was available for 35 cases, 2 cases were loss follow-up and 4 cases diagnosed as papilloma by core needle biopsy were followed up with imaging for at least 24 months. RESULTS: The pathologic diagnoses for the 35 papillary lesions obtained at core biopsy were benign in 24 cases, atypical in 7, and malignant in 4. Of those diagnosed as benign lesions at CNB, 7/24 turned out to be malignant. In the hyperplasia group, 5/7 were malignant. The total upgrade rate was 39%. The positive predict value was 100% and negative predict value was 61%. CONCLUSION: All papillary lesions of the breast diagnosed by CNB should be excised because a substantial number of lesions were upgraded of diagnoses at excision.


Asunto(s)
Biopsia con Aguja/métodos , Neoplasias de la Mama/patología , Carcinoma Papilar/patología , Adulto , Anciano , Mama/patología , Mama/cirugía , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Carcinoma Papilar/diagnóstico por imagen , Carcinoma Papilar/cirugía , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Ultrasonografía Intervencional , Ultrasonografía Mamaria
9.
Ultrasound Obstet Gynecol ; 32(4): 565-72, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18383556

RESUMEN

OBJECTIVES: To develop and evaluate a computer-aided diagnosis (CAD) system with automatic contouring and morphological analysis to aid in the classification of breast tumors using ultrasound. METHODS: We evaluated 118 breast lesions (34 malignant and 84 benign tumors). Each tumor contour was automatically extracted from the digitized ultrasound image. Nineteen practical morphological features from the extracted contour were calculated and principal component analysis (PCA) was applied to find independent features. A support vector machine (SVM) classifier utilized the selected principal vectors to identify the breast tumor as benign or malignant. In this study, all the cases were sampled with k-fold cross-validation (k = 10) to evaluate the performance by receiver-operating characteristics (ROC) curve analysis. RESULTS: The areas under the ROC curves for the proposed CAD systems using all morphological features and the lower-dimensional principal vector were 0.91 and 0.90, respectively. The classification ability for breast tumors using morphological information was good. CONCLUSIONS: This system differentiates benign from malignant breast tumors well and therefore provides a clinically useful second opinion. Moreover, the morphological features are nearly setting-independent and thus available to various ultrasound machines.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Diagnóstico por Computador/métodos , Ultrasonografía Mamaria/métodos , Adulto , Anciano , Algoritmos , Diagnóstico Diferencial , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Persona de Mediana Edad , Análisis de Componente Principal , Adulto Joven
10.
Int Endod J ; 40(9): 707-14, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17645514

RESUMEN

AIM: To compare the shaping ability of progressive versus constant taper shaft instruments in curved root canals of extracted human teeth. METHODOLOGY: A total of 40 root canals of mandibular molars with curvatures ranging between 20 degrees and 40 degrees were divided into two groups of 20 canals each and embedded in a muffle system. The root canals sectioned horizontally at three levels before preparation and then remounted into the mould. All root canals were prepared with ProTaper (progressive taper) or Hero Shaper (constant taper) instruments. Pre- and post-instrumentation radiographs and cross-sectional images were obtained. The parameters evaluated were: working safety (instrument failure, apical blockage and loss of working length) and shaping ability (straightening, cross-sectional area, transportation and centring ability). The data were analysed statistically using Student's t-test. RESULTS: No instrument fractured during preparation. One Hero Shaper instrument permanently deformed. Both instrument systems maintained working length well. The canals prepared with Hero Shaper instruments were straightened to a lesser degree (P < 0.05). ProTaper instruments removed more dentine in the coronal and the middle sections of the canals. Canals prepared with Hero Shaper instruments had less transportation (P < 0.01) and better centring ability (P < 0.05) in the apical section. CONCLUSIONS: Both instrument systems were safe to use and maintained working length well. The canals prepared with Hero Shaper had less transportation and were better centred in the apical region, possibly because their smaller taper reduced instrument stiffness.


Asunto(s)
Preparación del Conducto Radicular/instrumentación , Cavidad Pulpar/anatomía & histología , Cavidad Pulpar/diagnóstico por imagen , Diseño de Equipo , Falla de Equipo , Seguridad de Equipos , Humanos , Diente Molar/anatomía & histología , Diente Molar/diagnóstico por imagen , Radiografía
11.
Int Endod J ; 39(10): 791-9, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16948665

RESUMEN

AIM: To compare the shaping ability of progressive versus constant taper shaft designed instruments in simulated root canals. METHODOLOGY: Simulated L- and S-shaped resin canals were prepared by ProTaper (progressive taper) and high elasticity in rotation 642 (Hero 642) (constant taper) instruments (n = 10 canals in each case). The pre- and post-instrumentation images were recorded and assessment of the canal shape was completed with image pro plus 5.0. The width of resin removed was measured at 9 measuring points. Incidence of canal aberrations, instrument fracture, preparation time and change of working length were recorded. In addition, the change of curvature and centring ability were also assessed. The data were analysed statistically using Student's t-test or Fisher's exact-test. RESULTS: In both canal types, Hero 642 instruments prepared canals more rapidly (P < 0.01) and maintained working length significantly more accurately than ProTaper instruments (P < 0.05). In canals prepared with Hero 642 instruments, there was less change in curvature. Instrumentation with ProTaper results in transportation towards the outer aspect of the L-shaped curved canals in the apical part and the inner aspect of the S-shaped canals at the curve. Hero 642 instruments had a better centring ability in the apical part of the canal, but resulted in shapes with a poor taper. CONCLUSIONS: ProTaper and Hero 642 instruments prepared curved canals rapidly, maintained working length well and were relatively safe without creating perforations and danger zones. In both canal types, Hero 642 instruments maintained the original canal curvature better, and had a better centring ability in curved canals because of its constant taper design. The taper prepared by Hero 642 instruments in the coronal part of the canal was generally poor.


Asunto(s)
Instrumentos Dentales , Preparación del Conducto Radicular/instrumentación , Aleaciones Dentales , Cavidad Pulpar/anatomía & histología , Diseño de Equipo , Falla de Equipo , Modelos Dentales , Níquel , Factores de Tiempo , Titanio
12.
Neurology ; 66(12): 1845-9, 2006 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-16801648

RESUMEN

OBJECTIVE: To detect white matter abnormalities in patients with mild Alzheimer disease (AD) by diffusion tensor imaging and to determine their topographic relationship with gray matter atrophy. METHODS: Thirteen patients with mild AD and 16 normal age-matched volunteers underwent diffusion tensor imaging and three-dimensional spoiled gradient-recalled sequence scanning. Voxel-based morphometry was conducted to detect regions of gray matter atrophy in the AD group relative to the control group. Fractional anisotropy (FA) maps were processed using SPM2 to make voxel-wise comparison of anisotropy in whole brain between the two groups. The relationship between locations of abnormalities in the white and gray matter was examined. RESULTS: Significant reductions in anisotropy were found in the white matter of both medial temporal lobes, bilateral temporal stems, bilateral superior longitudinal fasciculi, bilateral internal capsules, and cerebral peduncles, as well as the white matter of left middle temporal gyrus and right superior parietal lobule, the body and genu of the corpus callosum, and the right lateral capsule in patients with AD. Although the decrease in FA was consistent with cortical volumetric reduction in both temporal lobes, the widespread involvement of bilateral superior longitudinal fasciculi was dominant in these white matter findings. CONCLUSIONS: Voxel-wise comparison of whole-brain anisotropy revealed widely distributed disintegration of white matter in mild Alzheimer disease (AD). The white matter shows a different pattern of degeneration from gray matter and may be an independent factor in the progress of AD.


Asunto(s)
Enfermedad de Alzheimer/clasificación , Enfermedad de Alzheimer/diagnóstico , Imagen de Difusión por Resonancia Magnética/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Fibras Nerviosas Mielínicas/patología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Procesamiento de Señales Asistido por Computador , Técnica de Sustracción
13.
Abdom Imaging ; 31(5): 596-7, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16534551

RESUMEN

We report a rare case of bilateral retrocaval ureters associated with duplicated inferior renal cava. A 69-year-old woman was sent to our emergency room for abdominal pain. Multidetector computed tomogram with multiplanar reconstruction revealed duplicated inferior renal cavae and the bilateral ureters were positioned behind the duplicated inferior vena cava. To our knowledge, coexistence of bilateral retrocaval ureters and duplicated inferior renal cavae has not been reported in the literature.


Asunto(s)
Tomografía Computarizada por Rayos X , Uréter/anomalías , Vena Cava Inferior/anomalías , Anciano , Femenino , Humanos , Interpretación de Imagen Radiográfica Asistida por Computador , Uréter/diagnóstico por imagen , Vena Cava Inferior/diagnóstico por imagen
14.
Comput Med Imaging Graph ; 29(6): 419-29, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16002263

RESUMEN

Since microcalcifications in X-ray mammograms are the primary indicator of breast cancer, detection of microcalcifications is central to the development of an effective diagnostic system. This paper proposes a two-stage detection procedure. In the first stage, a data driven, closed form mathematical model is used to calculate the location and shape of suspected microcalcifications. When tested on the Nijmegen University Hospital (Netherlands) database, data analysis shows that the proposed model can effectively detect the occurrence of microcalcifications. The proposed mathematical model not only eliminates the need for system training, but also provides information on the borders of suspected microcalcifications for further feature extraction. In the second stage, 61 features are extracted for each suspected microcalcification, representing texture, the spatial domain and the spectral domain. From these features, a sequential forward search (SFS) algorithm selects the classification input vector, which consists of features sensitive only to microcalcifications. Two types of classifiers-a general regression neural network (GRNN) and a support vector machine (SVM)--are applied, and their classification performance is compared using the Az value of the Receiver Operating Characteristic curve. For all 61 features used as input vectors, the test data set yielded Az values of 97.01% for the SVM and 96.00% for the GRNN. With input features selected by SFS, the corresponding Az values were 98.00% for the SVM and 97.80% for the GRNN. The SVM outperformed the GRNN, whether or not the input vectors first underwent SFS feature selection. In both cases, feature selection dramatically reduced the dimension of the input vectors (82% for the SVM and 59% for the GRNN). Moreover, SFS feature selection improved the classification performance, increasing the Az value from 97.01 to 98.00% for the SVM and from 96.00 to 97.80% for the GRNN.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Mamografía/métodos , Calcinosis/clasificación , Femenino , Humanos , Imagenología Tridimensional , Modelos Estadísticos , Taiwán
16.
J Otolaryngol ; 30(4): 231-4, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11771035

RESUMEN

OBJECTIVE: To investigate the variability in primary tumour volume in nasopharyngeal carcinoma and compare it with the tumour staging of the 1997 American Joint Committee on Cancer. DESIGN: Prospective study. SETTING: Tertiary care centre. METHOD: A series of 33 newly diagnosed patients who were treated with high-dose radiotherapy participated in the study. MAIN OUTCOME MEASURES: Using computed tomographic scans, primary tumour volumes were measured using the summation-of-areas technique, and the variability in tumour volume was determined. The Mann-Whitney test was used for statistical analysis. RESULTS: A large variation in primary tumour volume was observed, especially in advanced-stage cases. CONCLUSIONS: Nasopharyngeal carcinoma shows considerable variability in primary tumour volume. Incorporation of primary tumour volume may lead to further refinement of the 1997 tumour staging system.


Asunto(s)
Neoplasias Nasofaríngeas/patología , Nasofaringe/patología , Adulto , Anciano , Tamaño de la Célula , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Prospectivos , Tomografía Computarizada por Rayos X
17.
Mol Reprod Dev ; 56(3): 331-5, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10861998

RESUMEN

As a first step toward elucidation of the action of factors secreted by the epithelium of oviduct, differential display reverse transcription-polymerase chain reaction (DDRT-PCR) was used in this study to identify transcripts of such oviductal factors in gilts carrying various stages of early embryo development post hormone-induced ovulation. A total of 13 differentially expressed transcripts were identified between 50 and 120 hr post-hCG injection (between 1- and 8-cell embryonic stages). Twelve of these transcripts were found to be initially expressed at 96 hr post-hCG injection (at 4-cell embryonic stage) and beyond. Three of such genes were shown by sequence analysis to be the porcine transforming growth factor-alpha, the porcine transforming growth factor-beta-binding protein II and a porcine astral natriuretic factor receptor-like transcript. Only one differentially expressed gene was detected between 50-60 and 85 hr post-hCG injection, and this gene turned out to be the porcine follicle-stimulating hormone receptor. The remaining eight transcripts detected by DDRT-PCR were novel. Moreover, most of these newly expressed genes were found to be turned on at a time coincidental with that of the 4-cell block of porcine embryos cultured in vitro. Our results demonstrate that DDRT-PCR is a feasible approach for rapid identification of genes that are differentially expressed in oviductal epithelium. Some of the genes thus identified may be important for unhindered development of embryos in the oviduct.


Asunto(s)
Trompas Uterinas/embriología , Receptores de HFE/genética , Factor de Crecimiento Transformador alfa/genética , Animales , Epitelio , Femenino , Expresión Génica , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Porcinos
18.
J Otolaryngol ; 29(1): 23-7, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10709168

RESUMEN

OBJECTIVE: The purpose of this study was to determine if radiotherapy for nasopharyngeal carcinoma causes mucosal disease of the paranasal sinuses. DESIGN: This study was a retrospective study. SETTING: This study was conducted at a tertiary care centre. METHOD: A series of 69 newly diagnosed patients, without pre-existing sinus disease, who were treated with high-dose radiotherapy participated. MAIN OUTCOME MEASURES: The prevalence, severity, and time course of mucosal abnormalities were analyzed, as judged by consecutive computed tomographies (CTs). RESULTS: The CT study revealed that 58.8% of the postirradiation scans had mucosal disease of the sinuses. The maxillary sinus had the highest prevalence (42.3%) without statistical significance (p = .10). The difference by McNemar test for two follow-up scans was not significant (p = .48) and by Kappa test was significant (p = .04). The relationship between the prevalence and the time course post radiotherapy revealed that it remained a high prevalence until after the 4-year follow-up scans. CONCLUSIONS: The results of this study confirm that chronic sinus disease is a common late complication of radiotherapy and it persists for years. Thus, aggressive treatment is indicated.


Asunto(s)
Carcinoma/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Senos Paranasales/efectos de la radiación , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Senos Etmoidales/efectos de la radiación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Seno Maxilar/efectos de la radiación , Persona de Mediana Edad , Enfermedades de los Senos Paranasales/diagnóstico por imagen , Enfermedades de los Senos Paranasales/etiología , Senos Paranasales/diagnóstico por imagen , Prevalencia , Traumatismos por Radiación/diagnóstico por imagen , Traumatismos por Radiación/etiología , Dosificación Radioterapéutica , Estudios Retrospectivos , Seno Esfenoidal/efectos de la radiación
20.
Hepatogastroenterology ; 46(29): 2965-7, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10576383

RESUMEN

Portal vein aneurysms (PVAs) are rare lesions associated with congenital vascular anomalies or chronic portal hypertension. Although usually benign, they occasionally lead to complications such as aneurysmal rupture, porto-systemic shunts, mural thrombosis in the portal vein, and compression of the biliary tract. So far, the diagnosis of these lesions has been dependent on 2-dimensional imaging modalities such as computed tomography (CT) or magnetic resonance imaging (MRI), or invasive procedures such as percutaneous transhepatic portography. Here we present the first documented case of an extra-hepatic portal vein aneurysm evaluated by 3-dimensional CT angiography. This easily performed and accurate imaging technique may obviate the need for invasive angiographic procedures in the future for the 3-dimensional characterization of deep vascular malformations in the portal circulation.


Asunto(s)
Aneurisma/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Vena Porta , Portografía , Tomografía Computarizada por Rayos X , Adulto , Medios de Contraste , Femenino , Humanos , Yopamidol , Sensibilidad y Especificidad
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