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1.
Radiother Oncol ; 141: 149-155, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31522882

RESUMEN

PURPOSE/OBJECTIVE: To report biochemical control associated with single fraction 15 Gy high-dose-rate brachytherapy (HDR-BT) boost followed by external beam radiation (EBRT) in patients with intermediate-risk prostate cancer. MATERIALS AND METHODS: A retrospective chart review of all patients with intermediate-risk disease treated with a real-time ultrasound-based 15 Gy HDR-BT boost followed by EBRT between 2009 and 2016 at a single quaternary cancer center was performed. Freedom from biochemical failure (FFBF), cumulative incidence of androgen deprivation therapy use for biochemical or clinical failure post-treatment (CI of ADT) and metastasis-free survival (MFS) outcomes were measured. RESULTS: 518 patients met the inclusion criteria for this study. Median age at HDR-BT was 67 years (IQR 61-72). 506 (98%) had complete pathologic information available. Of these, 146 (28%) had favorable (FIR) and 360 (69%) had unfavorable (UIR) intermediate-risk disease. 83 (16%) received short course hormones with EBRT + HDR. Median overall follow-up was 5.2 years. FFBF was 91 (88-94)% at 5 years. Five-year FFBF was 94 (89-99)% and 89 (85-94)% in FIR and UIR patients, respectively (p = 0.045). CI of ADT was 4 (2-6)% at 5 years. Five-year CI of ADT was 1 (0-3)% and 5 (2-8)% in FIR and UIR patients, respectively (p = 0.085). MFS was 97 (95-98)% at 5 years. Five-year MFS was 100 (N/A-100)% and 95 (92-98)% in FIR and UIR patients, respectively (p = 0.020). CONCLUSION: In this large cohort of intermediate-risk prostate cancer patients, 15 Gy HDR-BT boost plus EBRT results in durable biochemical control and low rates of ADT use for biochemical failure.


Asunto(s)
Braquiterapia/métodos , Neoplasias de la Próstata/radioterapia , Anciano , Antagonistas de Andrógenos/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Dosificación Radioterapéutica , Estudios Retrospectivos
2.
Radiother Oncol ; 135: 170-177, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31015164

RESUMEN

BACKGROUND AND PURPOSE: To identify if, in intermediate risk prostate cancer (IR-PCa), the absolute percentage of biopsied tissue positive for pattern 4 disease (APP4) may be a predictor of outcome. MATERIALS AND METHODS: 411 patients with IR-PCa were retrospectively reviewed. APP4 was calculated based on biopsy reports. Multivariable competing risk analysis was then performed on optimized APP4 cutpoints to predict for biochemical failure (BF), androgen deprivation use for BF (ADT-BF) and development of metastases (MD). RESULTS: Median follow-up for the cohort was 5.2 (Inter Quartile Range: 2.9-6.6) years. Median baseline PSA was 7.3 (5.3-9.8) ng/mL. 234 (56.9%) patients had T1 and 177 (43.1%) had T2 disease. Median APP4 was 2.00 (0.75-7.50)%. 38 (9.3%) patients experienced BF. The optimal cutpoint of APP4 for BF was >3.3% with an area under the curve (AUC) of 0.66. 17 (4.1%) received ADT-BF. The ADT-BF cutpoint was >6.6% with an AUC of 0.72. Eight (2.0%) developed MD. The MD cutpoint was >17.5% with an AUC of 0.86. Using APP4 >3.3 vs ≤ 3.3, log-transformed baseline PSA ln(PSA) (HR 2.5, 1.1-6.1; p = 0.037) and APP4 (HR 2.3, 1.1-4.7; p = 0.031) predicted for BF. Using APP4 >6.6 vs ≤ 6.6, ln(PSA) (HR 4.2, 1.4-12.4; p = 0.010) and APP4 (HR 3.7, 1.4-10.0; p = 0.009) were predictive of ADT-BF. APP4 >17.5 vs ≤ 17.5 alone was predictive of MD (HR 25.7, 4.9-135.3; p < 0.001). CONCLUSION: APP4 cutpoints of >3.3%, >6.6% and >17.5% were strongly associated with increased risk of BF, ADT-BF and developing MD respectively. These findings may inform future practice when treating IR-PCa but require external validation.


Asunto(s)
Braquiterapia/métodos , Neoplasias de la Próstata/radioterapia , Anciano , Biopsia , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/patología , Dosificación Radioterapéutica , Estudios Retrospectivos
3.
Radiother Oncol ; 126(3): 534-540, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28919003

RESUMEN

BACKGROUND AND PURPOSE: The use of Stereotactic Body Radiotherapy (SBRT) for bone metastases is increasing rapidly. Therefore, knowledge of the inter-observer differences in tumor volume delineation is essential to guarantee precise dose delivery. The aim of this study is to compare inter-observer agreement in bone metastases delineated on different imaging modalities. MATERIAL AND METHODS: Twenty consecutive patients with bone metastases treated with SBRT were selected. All patients received CT and MR imaging in treatment position prior to SBRT. Five observers from three institutions independently delineated gross tumor volume (GTV) on CT alone, CT with co-registered MRI and MRI alone. Four contours per imaging modality per patient were available, as one set of contours was shared by 2 observers. Inter-observer agreement, expressed in generalized conformity index [CIgen], volumes of contours and contours center of mass (COM) were calculated per patient and imaging modality. RESULTS: Mean GTV delineated on MR (45.9±52.0cm3) was significantly larger compared to CT-MR (40.2±49.4cm3) and CT (34.8±41.8cm3). A considerable variation in CIgen was found on CT (mean 0.46, range 0.15-0.75) and CT-MRI (mean 0.54, range 0.17-0.71). The highest agreement was found on MRI (mean 0.56, range 0.20-0.77). The largest variations of COM were found in anterior-posterior direction for all imaging modalities. CONCLUSIONS: Large inter-observer variation in GTV delineation exists for CT, CT-MRI and MRI. MRI-based GTV delineation resulted in larger volumes and highest consistency between observers.


Asunto(s)
Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/secundario , Neoplasias Óseas/patología , Estudios de Cohortes , Humanos , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/normas , Variaciones Dependientes del Observador , Estudios Prospectivos , Radiocirugia , Planificación de la Radioterapia Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Tomografía Computarizada por Rayos X/normas , Carga Tumoral
4.
Aliment Pharmacol Ther ; 42(5): 599-606, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26096497

RESUMEN

BACKGROUND: Controversy exists regarding glucocorticoids therapy and the risk of peptic ulcer bleeding (PUB). AIM: The present study was undertaken to determine whether short-term use of glucocorticoids is associated with the occurrence of peptic ulcer bleeding. METHODS: The records of adult patients hospitalised for newly diagnosed peptic ulcer bleeding from 2000 to 2012 were retrieved from the Taiwan National Health Insurance Research Database, a nationwide population-based registry system. The association between systemic glucocorticoids usage and peptic ulcer bleeding was determined with a conditional logistic regression model comparing cases and controls during time windows of 7, 14 and 28 days using a case-crossover design. RESULTS: Of the 8894 enrolled patients, the adjusted self-matched odds ratios for peptic ulcer bleeding after exposure to the glucocorticoids were 1.37 (95% CI: 1.12-1.68, P = 0.003) for the 7-day window, 1.66 (95% CI: 1.38-2.00, P < 0.001) for the 14-day window and 1.84 (95% CI: 1.57-2.16, P < 0.001) for the 28-day window. Moderate to high, but not low dose glucocorticoids (methylprednisolone <4 mg/day or its equivalence) were associated with an increased risk of peptic ulcer bleeding. Concomitant use of a nonselective nonsteroidal anti-inflammatory drug (NSAID) or aspirin further elevated the risk. However, it does not eliminate the effect of underlying diseases flare-up that may have placed the patients at risk for peptic ulcer bleeding in this kind of study design. CONCLUSIONS: Short-term (7-28 days) exposure to glucocorticoids is significantly associated with peptic ulcer bleeding; this risk seems dose-dependent and is higher when nonselective NSAIDs or aspirin are used concurrently.


Asunto(s)
Glucocorticoides/efectos adversos , Úlcera Péptica Hemorrágica/inducido químicamente , Adulto , Anciano , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/efectos adversos , Aspirina/administración & dosificación , Aspirina/efectos adversos , Estudios de Casos y Controles , Estudios Cruzados , Bases de Datos Factuales , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Combinación de Medicamentos , Femenino , Hospitalización , Humanos , Modelos Logísticos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Úlcera Péptica Hemorrágica/epidemiología , Proyectos de Investigación , Taiwán/epidemiología , Factores de Tiempo
5.
Appl Radiat Isot ; 62(4): 561-7, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15701410

RESUMEN

An approach based on utilization of epithermal neutron activation analysis (ENAA) is proposed for determination of trace Al in silicon carbide (SiC) materials. The feasibility and restrictions of the ENAA were evaluated in terms of the associated uncertainties that resulted from counting and from propagation in calculations. Experimental measurements were carried out under the specified irradiation and measurement conditions, where the results of a set of SiC standards for accuracy testing were compared with the calculated uncertainties. It is shown that the epithermal neutron activation is a simple and reliable method practically useful for analysis of SiC containing Al in concentrations (f(Al)) higher than 10(-3) weight fraction by the use of a typical nuclear reactor; the associated uncertainties can be suppressed to less than 12%. The influences of neutron quality or the cadmium ratio in 27Al(n,gamma)28Al reaction on the applicable concentrations of Al in SiC are also predicted and discussed.

6.
J Opt Soc Am A Opt Image Sci Vis ; 18(11): 2641-58, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11688855

RESUMEN

We propose a novel image-recovery method using the covariance matrix of the red-green-blue (R-G-B) color histogram and tensor theories. The image-recovery method is called the color histogram normalization algorithm. It is known that the color histograms of an image taken under varied illuminations are related by a general affine transformation of the R-G-B coordinates when the illumination is changed. We propose a simplified affine model for application with illumination variation. This simplified affine model considers the effects of only three basic forms of distortion: translation, scaling, and rotation. According to this principle, we can estimate the affine transformation matrix necessary to recover images whose color distributions are varied as a result of illumination changes. We compare the normalized color histogram of the standard image with that of the tested image. By performing some operations of simple linear algebra, we can estimate the matrix of the affine transformation between two images under different illuminations. To demonstrate the performance of the proposed algorithm, we divide the experiments into two parts: computer-simulated images and real images corresponding to illumination changes. Simulation results show that the proposed algorithm is effective for both types of images. We also explain the noise-sensitive skew-rotation estimation that exists in the general affine model and demonstrate that the proposed simplified affine model without the use of skew rotation is better than the general affine model for such applications.

7.
Appl Radiat Isot ; 54(5): 811-20, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11258531

RESUMEN

The radioactive tracer technique was applied to investigate the out-diffusion of the transition metals (Cu, Fe and Co) from deep ultraviolet (DUV) photoresist into underlying substrate. Two important process parameters, viz., baking temperatures and substrate types (i.e., bare silicon, polysilicon, silicon oxide and silicon nitride), were evaluated. Results indicate that the out-diffusion of Co is insignificant, irrespective of the substrate type and baking temperature. The out-diffusion of Cu is significant for substrates of bare silicon and polysilicon but not for silicon oxide and nitride; for Fe, the story is reversed. The substrate type appears to strongly affect the diffusion, while the baking temperature does not. Also, the effect of solvent evaporation was found to play an important role in impurity diffusion. Using the method of numerical analysis, a diffusion profile was depicted in this work to describe the out-diffusion of metallic impurities from photoresist layer under various baking conditions. In addition, the effectiveness of various wet-cleaning recipes in removing metallic impurities such as Cu, Fe and Co was also studied using the radioactive tracer technique. Among the six cleaning solutions studied, SC2 and SPM are the most effective in impurity removal. An out-diffusion cleaning model was first proposed to describe the cleaning process. A new cleaning coefficient, h(T), was suggested to explain the cleaning effect. The cleaning model could explain the tracer results.

8.
Appl Radiat Isot ; 54(1): 123-9, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11144242

RESUMEN

Dose estimation was conducted for internal phosphorus-32 exposure in one young male subject from repeated oral mis-ingestion for > 1 year. Since disclosure for previous continuous contamination, a series of urine samples were collected from this individual weekly for a period of >2 months. P-32 radioactivity in urine samples were measured by the acid precipitation method. Estimation for retrospective total effective dose equivalent received by this subject was conducted for cumulative internal dose estimation. A minimum of 9.4 mSv was estimated for an assumed single ingestion. As this was a rare case in radiation protection and internal radiation dosimetry, its implications were of considerable significance.


Asunto(s)
Radioisótopos de Fósforo/farmacocinética , Dosis de Radiación , Administración Oral , Adulto , Humanos , Masculino , Matemática , Modelos Biológicos , Radioisótopos de Fósforo/orina , Monitoreo de Radiación , Radiometría/métodos
9.
Neurology ; 54(5): 1124-31, 2000 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-10720286

RESUMEN

OBJECTIVE: To investigate the frequency and clinical determinants of dementia after ischemic stroke. METHODS: The authors administered neurologic, neuropsychological, and functional assessments to 453 patients (age 72.0 +/- 8.3 years) 3 months after ischemic stroke. They diagnosed dementia using modified Diagnostic and Statistical Manual of Mental Disorders, 3rd ed., revised criteria requiring deficits in memory and two or more additional cognitive domains as well as functional impairment. RESULTS: The authors diagnosed dementia in 119 of the 453 patients (26.3%). Regarding dementia subtypes, 68 of the 119 patients (57.1%) were diagnosed with vascular dementia, 46 patients (38.7%) were diagnosed with AD with concomitant stroke, and 5 patients (4.2%) had dementia for other reasons. Logistic regression suggested that dementia was associated with a major hemispheral stroke syndrome (OR 3.0), left hemisphere (OR 2.1) and right hemisphere (OR 1.8) infarct locations versus brainstem/cerebellar locations, infarcts in the pooled anterior and posterior cerebral artery territories versus infarcts in other vascular territories (OR 1.7), diabetes mellitus (OR 1.8), prior stroke (OR 1.7), age 80 years or older (OR 12.7) and 70 to 79 years (OR 3.9) versus 60 to 69 years, 8 or fewer years of education (OR 4.1) and 9 to 12 years of education (OR 3.0) versus 13 or more years of education, black race (OR 2.6) and Hispanic ethnicity (OR 3.1) versus white race, and northern Manhattan residence (OR 1.6). CONCLUSIONS: Dementia is frequent after ischemic stroke, occurring in one-fourth of the elderly patients in the authors' cohort. The clinical determinants of dementia include the location and severity of the presenting stroke, vascular risk factors such as diabetes mellitus and prior stroke, and host characteristics such as older age, fewer years of education, and nonwhite race/ethnicity. The results also suggest that concomitant AD plays an etiologic role in approximately one-third of cases of dementia after stroke.


Asunto(s)
Isquemia Encefálica/fisiopatología , Demencia/fisiopatología , Accidente Cerebrovascular/fisiopatología , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/complicaciones , Demencia/complicaciones , Demencia/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Estudios Prospectivos , Accidente Cerebrovascular/complicaciones
10.
J Am Geriatr Soc ; 47(7): 824-9, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10404926

RESUMEN

OBJECTIVE: To investigate the influence of dementia status on treatment for the secondary prevention of stroke in older patients. DESIGN: Based on patient examinations and medical record review, we investigated the frequency of aspirin and/or warfarin use at hospital discharge for the prevention of recurrent stroke in older patients hospitalized with acute ischemic stroke. SETTING: A large academic medical center. PARTICIPANTS: A cohort of 272 patients, mean age 72.1 +/- 8.5 years. MEASUREMENTS: We performed neurologic examinations and reviewed medical records to investigate the effects of a clinical diagnosis of dementia and other potentially relevant factors on treatment with aspirin or warfarin at hospital discharge. RESULTS: Thirty-one patients (11.4%) were not prescribed aspirin or warfarin at hospital discharge. Logistic regression determined that dementia (odds ratio (OR) = 2.57, 95% confidence interval (CI), 1.04-6.30) was a significant independent determinant of nontreatment with aspirin or warfarin, adjusting for abnormal gait (OR = 2.01, CI, .88-4.59); discharge to a nursing home or other institutional residence (OR = 2.55, CI, .83-7.81); cardiac disease (OR = .39, CI, .16-.95); cortical infarct location (OR = .45, CI, .18-1.10); male sex (OR = .47, CI, .20-1.15); age 80+ (OR = 1.14, CI, .46-2.82) and age 70-79 (OR = .96, CI, .32-2.88) versus age 60-69. CONCLUSIONS: Our results suggest that dementia is a significant independent determinant of nontreatment with aspirin or warfarin when otherwise indicated for the prevention of recurrent stroke. The underutilization of aspirin and warfarin in older stroke patients with dementia may be a modifiable basis for their increased risk of recurrence and death.


Asunto(s)
Anticoagulantes/uso terapéutico , Aspirina/uso terapéutico , Trastornos Cerebrovasculares/complicaciones , Trastornos Cerebrovasculares/prevención & control , Demencia/complicaciones , Selección de Paciente , Inhibidores de Agregación Plaquetaria/uso terapéutico , Pautas de la Práctica en Medicina/estadística & datos numéricos , Warfarina/uso terapéutico , Anciano , Anciano de 80 o más Años , Demencia/diagnóstico , Utilización de Medicamentos , Femenino , Evaluación Geriátrica , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Examen Neurológico , Alta del Paciente , Estudios Retrospectivos , Factores de Riesgo
11.
Pediatr Neurol ; 19(2): 100-4, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9744627

RESUMEN

Intracranial arachnoid cysts are benign development anomalies that may be clinically asymptomatic. The authors describe 30 children with intracranial arachnoid cysts in terms of clinical manifestations and relations to the associated brain anomalies or lesions. The mean age at onset of clinical manifestations was 4 years, 7 months (range 1 day to 14 years). The mean age at diagnosis was 6 years, 2 months (range 10 days to 16 years). Most patients with nonprogressive symptoms, such as seizures and headache, had focal epileptiform discharges on electroencephalogram, and they benefited from antiepileptic drugs. Surgery resulted in only partial reduction in both cyst size and seizure frequency in patients with intractable seizures, and it also failed to improve some neurologic signs, such as sexual precocity or cranial neuropathy resulting from long-term compression of arachnoid cysts. We conclude that the only absolute indication for surgery is the presence of progressive hydrocephalus or intracranial hypertension. The associated anomalies or lesions include brain tumors, giant nevocellular nevi, achondroplasia, microphthalmia, intracystic hemorrhage, dysgenesis of the corpus callosum, and heterotopia.


Asunto(s)
Quistes Aracnoideos/complicaciones , Encefalopatías/complicaciones , Adolescente , Quistes Aracnoideos/diagnóstico , Quistes Aracnoideos/fisiopatología , Quistes Aracnoideos/cirugía , Encefalopatías/diagnóstico , Encefalopatías/fisiopatología , Encefalopatías/cirugía , Niño , Preescolar , Epilepsia/etiología , Epilepsia/fisiopatología , Femenino , Cefalea/etiología , Cefalea/fisiopatología , Humanos , Lactante , Recién Nacido , Imagen por Resonancia Magnética , Masculino , Sistema Nervioso/fisiopatología , Periodo Posoperatorio , Convulsiones/etiología , Convulsiones/fisiopatología , Tomografía Computarizada por Rayos X , Insuficiencia del Tratamiento
12.
J Public Health Dent ; 57(3): 159-62, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9383754

RESUMEN

OBJECTIVES: This article develops and compares gender-specific predictive models for willingness to treat HIV-infected patients (PHIV+) for male and female private general practice dentists (GPDs). METHODS: Based on mail survey data collected in Manhattan and Queens, New York City (73.3% response rate), hierarchical multiple regression analyses were conducted for male and female dentists 50 years of age or younger (n = 763) and for those in solo practice. RESULTS: The gender-specific predictive models (R2s = 0.72) do not differ, except for the influence of practice viability, a moderately strong, statistically significant predictor for men, while the least powerful, statistically nonsignificant predictor for women. This distinction remains for solo male and female practitioners. Informal/formal collegial norms are more influential predictors within the solo female model than within the solo male model. CONCLUSIONS: Findings are encouraging for further work in developing predictive models for clinician subpopulations, with an eye toward developing intervention strategies that reflect key predictive factors for each group.


Asunto(s)
Actitud del Personal de Salud , Actitud Frente a la Salud , Atención Dental para Enfermos Crónicos , Odontólogos , Seropositividad para VIH , Síndrome de Inmunodeficiencia Adquirida , Factores de Edad , Competencia Clínica , Femenino , Predicción , Odontología General , Humanos , Relaciones Interprofesionales , Masculino , Persona de Mediana Edad , Ciudad de Nueva York , Exposición Profesional , Administración de la Práctica Odontológica , Práctica Privada , Análisis de Regresión , Seguridad , Factores Sexuales , Encuestas y Cuestionarios
13.
Artículo en Inglés | MEDLINE | ID: mdl-9151466

RESUMEN

In order to identify the brain lesions of symptomatic/cryptogenic partial epilepsies (S/CPEs) in infants and children, magnetic resonance imaging (MRI) studies, thorough encephalographic (EEGic) studies, and detailed clinical and neurologic evaluations were obtained in 300 infants and children who were diagnosed to have S/CPEs with onset before the age of 13 years during the past 7 years. The overall detection rate of brain lesions by MRI was 41.7% (125/300). Congenital malformations (18 cases), vascular malformations (9 cases), neurocutaneous syndromes (13 cases), and space-taking lesions (20 cases) constitute a large percentage of SPEs in infants and children. A variety of insults such as infection, ischemia, hemorrhage, trauma and metabolic disorders can result in destructive parenchymal loss lesions including porencephaly, focal atrophy, hemiatrophy, and diffuse brain atrophy (20 cases). Major etiologic factors leading to infarction, encephalomalacia, leukomalacia, included trauma, hvpoxicischemic encephalopathy (HIE), systemic lupus erythematosus (SLE), encephalitis, vasculitis, venous thrombosis, vasculopathies, and heart problems (22 cases). Mesial temporal sclerosis (MTS) could be evidenced in around 20% (18/95) of cases with temporal lobe epilepsy (TLE), which was strongly associated with past histories of febrile seizures and encephalitis complicated by status epileptics. However, cases with porencephaly, global atrophy or delayed myelination of unilateral temporal lobe on MRI were more related to HIE. With the advent of neuroimaging techniques, particularly MRI, a wide variety of underlying pathology can be detected as a cause of symptomatic partial epilepsies in pediatric patients. The occurrence of S/CPE indicates the presence of localized brain dysfunction, and many of the causes are potentially treatable. An orderly and thorough clinical and laboratory investigations, as well as neuroimaging studies should be made to diagnose and treat any underlying conditions.


Asunto(s)
Encéfalo/patología , Epilepsias Parciales/patología , Imagen por Resonancia Magnética , Adolescente , Encéfalo/anomalías , Encefalopatías/patología , Niño , Preescolar , Electroencefalografía , Epilepsia del Lóbulo Frontal/patología , Epilepsia del Lóbulo Temporal/patología , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Examen Neurológico , Estudios Prospectivos
14.
Sci Total Environ ; 193(2): 111-9, 1996 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-9043144

RESUMEN

The 129I and 129I/127I ratios in mammalian thyroids were determined by neutron activation analysis to estimate the 129I concentrations in the biosphere due to fallout accumulation during the past decades in this island. The average 129I/127I ratio in thyroids of grazing animals, bovine and ovine, is about 1 x 10(-9), three times higher than that of hogs. The 129I/127I ratio in twin water collected during the same period was found to be as high as 1.7 x 10(-8) and it is supposed to be the predominant source of 129I in the biosphere. The 129I concentrations in these mammalian thyroids are similar to those of non-direct contamination areas of the world, where the terrestrial 129I contents are influenced by the global fallout.


Asunto(s)
Bovinos/metabolismo , Radioisótopos de Yodo/metabolismo , Yodo/metabolismo , Ovinos/metabolismo , Porcinos/metabolismo , Glándula Tiroides/metabolismo , Animales , Contaminantes Ambientales/metabolismo , Isótopos de Yodo , Marcaje Isotópico , Análisis de Activación de Neutrones , Taiwán
15.
Artículo en Inglés | MEDLINE | ID: mdl-8755175

RESUMEN

Nine patients below 20 years of age (4 males and 5 females), who were diagnosed to have acute disseminated encephalomyelitis (ADEM) by clinical findings and magnetic resonance imaging (MRI), were reviewed retrospectively. They ranged from 4 months to 20 years of age with an average of 8.6 years. Seven patients (78%) received neurophysiological studies, which included electroencephalography, multimodality evoked potentials (EPs), nerve conduction velocity and/or F-wave measurement. The presentation symptoms were mainly headache, vomiting, consciousness change and motor deficits. Seven (78%) of nine patients had symptoms preceded by fever or upper respiratory tract infections; one (11%) was preceded by trivalent mumps, measles, rubella vaccination and no definite predisposing factor was found in another. Computed tomography (CT) scans were abnormal in five (71 %) of seven children, while MRI showed multiple lesions in seven (78%) of nine children. The lesions in MRI were mainly in the brainstem (n = 6), basal ganglion (n = 5), thalamus (n = 4), periventricular white matter (n = 4) and cerebellum (n = 4). EPs disclosed spinal cord involvement in all patients who received the examination. Peripheral neuropathy was disclosed in one patient. It was concluded that associated radiculoneuropathy is possible in patients with ADEM. Both MRI and neurophysiologic studies are complementary for diagnosis of ADEM.


Asunto(s)
Encéfalo/patología , Encefalomielitis Aguda Diseminada/diagnóstico , Adolescente , Adulto , Encéfalo/fisiopatología , Niño , Preescolar , Electroencefalografía , Encefalomielitis Aguda Diseminada/fisiopatología , Potenciales Evocados , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Conducción Nerviosa , Estudios Retrospectivos
16.
Artículo en Inglés | MEDLINE | ID: mdl-7793286

RESUMEN

Four female children with clinically-definite diagnoses of multiple sclerosis (MS) were studied with multimodal evoked potentials (EPs), electroencephalogram (EEG), cerebrospinal fluid (CSF) analysis, computed tomography (CT) and magnetic resonance imaging (MRI). Correlations among the clinical features, neuroimaging and neurophysiological studies were also evaluated. Their ages of the onset ranged from 5 to 11 years. The clinical evolution in the all four MS cases was relapsing-remitting form. MRI studies in three cases showed abnormal demyelinating plaques in the brainstem, cerebellum and white matter of the cerebrum. CT examination, performed in the other MS case, did not reveal hypodensic lesion. Despite that MRI failed to document optical nerve lesions, three cases had abnormal visual evoked potentials (VEPs). Somatosensory evoked potentials (SSEPs) were abnormal in three cases. Brainstem auditory evoked potentials (BAEPs) were abnormal in two cases presenting with signs of brainstem dysfunction. The conclusion was that paraclinical evidences obtained from MRI and multimodal evoked potential studies are of value as an aid in localizing involved areas and detecting silent lesions in children with MS.


Asunto(s)
Esclerosis Múltiple/fisiopatología , Adolescente , Niño , Electroencefalografía , Potenciales Evocados , Femenino , Humanos , Imagen por Resonancia Magnética , Esclerosis Múltiple/diagnóstico
17.
Biol Trace Elem Res ; 39(2-3): 117-28, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-7509169

RESUMEN

Blackfoot disease is a peripheral vascular disease resulting in gangrene of the lower extremities. Though extensive epidemiological study has implicated that high arsenic content in artesian well water of the endemic area bears some important connection with the disease, the etiology of the disease is still unknown. In this study, attention is paid to multielement determination in order to find out whether the trace elements in hair of Blackfoot disease patients are different from those of the controls. Experimental results indicate that the concentrations of As and Se in hair of patients are significantly higher than those of the controls, but Ca and Zn are significantly lower than those of the controls. The possible connection of these elements with the etiology of the disease is discussed.


Asunto(s)
Cabello/química , Enfermedades Vasculares Periféricas/metabolismo , Oligoelementos/análisis , Arsénico/análisis , Cadmio/análisis , Calcio/análisis , Exposición a Riesgos Ambientales , Enfermedades del Pie/metabolismo , Gangrena/etiología , Gangrena/metabolismo , Humanos , Selenio/análisis , Agua/química , Zinc/análisis
18.
Zhonghua Yi Xue Za Zhi (Taipei) ; 52(2): 109-15, 1993 Aug.
Artículo en Chino | MEDLINE | ID: mdl-8402364

RESUMEN

Ten hypertensive intracerebral hemorrhagic comatose patients in the Neurosurgical Intensive Care Unit were involved in this study. The ten were within the range of 5 to 8 by Glasgow Coma Scale, and all had undergone tracheostomy. During suction of the airway for 20 seconds in 4 areas (trachea, bronchus, nasal and oral cavities), the data of intracranial pressure (ICP), arterial blood pressure, pulse rate (PR) and respiration rate (RR) were recorded. Results were analyzed for ICP, mean arterial blood pressure (MABP), PR, RR, and cerebral perfusion pressure (CPP) at the 5th, 10th, 15th and 20th seconds in the above-mentioned areas. The ICP was found to be significantly increased, and above the 20 mmHg mark, during suction of the bronchus or nasal cavity for 5 seconds. The MABP also showed significant increase, to above the 110 mmHg mark during 5-second suction of the trachea or nasal cavity or during suction of the bronchus or oral cavity for 10 seconds. However, during the suction of the four airway areas, PR and RR were less influenced and the CPP was not decreased or significantly changed. The conclusion of this study was that suction in the areas of trachea, bronchus and nasal cavity, should not exceed 5 to 10 seconds; in the oral cavity, it may be done within 10 to 15 seconds and at each procedure of airway suction. If it is not possible to clean the sputum or secretion in one procedure, the patient should be allowed to rest for about one minute or become stabilized as determined by watching the monitors of ICP, BP, PR, and RR.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Hemorragia Cerebral/fisiopatología , Coma/fisiopatología , Hipertensión/fisiopatología , Presión Intracraneal , Esputo , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Succión , Factores de Tiempo
19.
Health Phys ; 65(2): 147-55, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8330960

RESUMEN

Studies of the physical and chemical properties of radioactive aerosols produced in different work environments were made at Chin-Shan nuclear power plant in Taiwan. These properties, including particle mass- and activity-size distributions, elemental and radionuclide compositions, and solubility lung class, are essential for the assessment of internal dose equivalents from the inhalation of radioactive aerosols. Several practices and environments studied include thermal arc cutting, grinding, sandblasting, and noble gas progeny. For physical analyses, cascade impactors, scanning electron microscopy with energy-dispersive x-ray analysis, inductively coupled plasma atomic emission spectrometry, and neutron activation analysis were applied. For chemical analyses, the solubility lung class was determined, in vitro, with the measurement of aerosol dissolution rates in simulated biological fluids. Results of these analyses were used to calculate the annual limit on intake, the derived air concentration, and committed dose equivalents for radiological protection against radioactive aerosols produced at Chin-Shan nuclear power plant.


Asunto(s)
Aerosoles , Energía Nuclear , Exposición Profesional , Protección Radiológica , Radioisótopos , Humanos , Dosis de Radiación
20.
Artículo en Inglés | MEDLINE | ID: mdl-1296433

RESUMEN

The activity of urinary N-acetyl-beta-glucosaminidase (NAG) was measured in random urines using the ratio (NAG index) of NAG to grams of urine creatinine in 102 epileptic children taking antiepileptic drugs (AEDs). A high urinary NAG index (2 SD or more above the mean for the age-matched control/normal subjects) was detected in 40 (39%, 40/102) epileptic children with AEDs. None of the 40 epileptic children with abnormal urinary NAG excretion had significant proteinuria. Among the 83 epileptic children under monotherapy, 29 cases (35%) had elevated urinary NAG excretion. Valproic acid presented the highest incidence of abnormal urinary NAG index (78%, 7/9 cases) within the monotherapy group, and the incidence was statistically significantly higher than that (26%, 14/55) in the carbamazepine group (p < 0.005). In the monotherapy group, no significant difference in serum levels of AEDs was found between children with normal urinary NAG excretion and those with abnormal. Nineteen epileptic children were treated with more than one AEDs. Eleven of them (58%, 11/19 cases) had a high urinary NAG index. The incidence of high urinary NAG index in the polytherapy group and that in monotherapy group was not significantly different (p > 0.05). This study suggests that AEDs may be potentially nephrotoxic and that urinary NAG may play a role in screening renal tubular injury in epileptic children under therapy of AEDs. Further investigation should be conducted to determine whether the effect of AEDs on renal tubular cells is or is not reversible.


Asunto(s)
Acetilglucosaminidasa/orina , Anticonvulsivantes/farmacología , Epilepsia/orina , Adolescente , Anticonvulsivantes/uso terapéutico , Niño , Preescolar , Creatinina/orina , Epilepsia/tratamiento farmacológico , Femenino , Humanos , Lactante , Masculino
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