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1.
J Nucl Cardiol ; 30(3): 1075-1087, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36266526

RESUMEN

BACKGROUND: Somatostatin receptor is expressed in sarcoid granulomas, and preliminary clinical studies have shown that myocardial sarcoidosis can be identified on somatostatin receptor-targeted PET. We examined the potential clinical use of 68Ga-DOTATATE PET/CT for diagnosis and response assessment in cardiac sarcoidosis compared to 18F-FDG PET/CT. METHODS: Eleven cardiac sarcoidosis patients with 18F-FDG PET/CT were prospectively enrolled for cardiac 68Ga-DOTATATE PET/CT. The two PET/CT studies were interpreted independently and were compared for patient-level and segment-level concordance, as well as for the degree of radiotracer uptake. Follow-up 68Ga-DOTATATE PET/CT was performed in eight patients. RESULTS: Patient-level concordance was 91%: ten patients had multifocal DOTATATE uptake (active cardiac sarcoidosis) and one patient showed diffuse DOTATATE uptake. Segment-level agreement was 77.1% (Kappa 0.53 ± 0.07). The SUVmax-to-blood pool ratio was lower on 68Ga-DOTATATE PET/CT (3.2 ± 0.6 vs. 4.9 ± 1.5, P = 0.006 on paired t test). Follow-up 68Ga-DOTATATE PET/CT showed one case of complete response and one case of partial response, while 18F-FDG PET/CT showed four cases of response, including three with complete response. CONCLUSION: Compared to 18F-FDG PET/CT, 68Ga-DOTATATE PET/CT can identify active cardiac sarcoidosis with high patient-level concordance, but with moderate segment-level concordance, low signal-to-background ratio, and underestimation of treatment response.


Asunto(s)
Compuestos Organometálicos , Sarcoidosis , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones , Fluorodesoxiglucosa F18 , Radioisótopos de Galio , Receptores de Somatostatina
2.
Occup Environ Med ; 79(2): 120-126, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34535537

RESUMEN

OBJECTIVES: Human leukocyte antigen-DP beta 1 (HLA-DPB1) with a glutamic acid at the 69th position of the ß chain (E69) genotype and inhalational beryllium exposure individually contribute to risk of chronic beryllium disease (CBD) and beryllium sensitisation (BeS) in exposed individuals. This retrospective nested case-control study assessed the contribution of genetics and exposure in the development of BeS and CBD. METHODS: Workers with BeS (n=444), CBD (n=449) and beryllium-exposed controls (n=890) were enrolled from studies conducted at nuclear weapons and primary beryllium manufacturing facilities. Lifetime-average beryllium exposure estimates were based on workers' job questionnaires and historical and industrial hygienist exposure estimates, blinded to genotype and case status. Genotyping was performed using sequence-specific primer-PCR. Logistic regression models were developed allowing for over-dispersion, adjusting for workforce, race, sex and ethnicity. RESULTS: Having no E69 alleles was associated with lower odds of both CBD and BeS; every additional E69 allele increased odds for CBD and BeS. Increasing exposure was associated with lower odds of BeS. CBD was not associated with exposure as compared to controls, yet the per cent of individuals with CBD versus BeS increased with increasing exposure. No evidence of a gene-by-exposure interaction was found for CBD or BeS. CONCLUSIONS: Risk of CBD increases with E69 allele frequency and increasing exposure, although no gene by environment interaction was found. A decreased risk of BeS with increasing exposure and lack of exposure response in CBD cases may be due to the limitations of reconstructed exposure estimates. Although reducing exposure may not prevent BeS, it may reduce CBD and the associated health effects, especially in those carrying E69 alleles.


Asunto(s)
Beriliosis/genética , Berilio/toxicidad , Cadenas beta de HLA-DP/genética , Exposición Profesional/efectos adversos , Beriliosis/epidemiología , Estudios de Casos y Controles , Enfermedad Crónica , Femenino , Genotipo , Humanos , Masculino , Polimorfismo Genético , Estudios Retrospectivos
3.
Respir Res ; 22(1): 107, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33863318

RESUMEN

Sarcoidosis and chronic beryllium disease (CBD) are phenocopies, however the latter one has a clear trigger factor that is beryllium exposure. This study analyses single nucleotide polymorphisms (SNPs) in a large cohort for beryllium-exposed persons. SNPs were chosen for their relevance in sarcoidosis. Even though one of largest cohorts of beryllium-exposed persons was analysed, no statistically relevant association between any SNP and CBD could be verified. Notably, some SNPs exhibit inverse OR for beryllium sensitization and CBD with nominally statistical significance, which allows hypothesizing about pathophysiological role of genes for the disease triggering and development.


Asunto(s)
Beriliosis/genética , Berilio/efectos adversos , Butirofilinas/genética , ADN/genética , Exposición Profesional/efectos adversos , Polimorfismo de Nucleótido Simple , Beriliosis/metabolismo , Butirofilinas/metabolismo , Enfermedad Crónica , Femenino , Humanos , Masculino
4.
Am J Respir Crit Care Med ; 197(2): 225-234, 2018 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-28846439

RESUMEN

RATIONALE: The etiology of sarcoidosis is unknown, but microbial agents are suspected as triggers. OBJECTIVES: We sought to identify bacterial, fungal, or viral lineages in specimens from patients with sarcoidosis enriched relative to control subjects using metagenomic DNA sequencing. Because DNA from environmental contamination contributes disproportionately to samples with low authentic microbial content, we developed improved methods for filtering environmental contamination. METHODS: We analyzed specimens from subjects with sarcoidosis (n = 93), control subjects without sarcoidosis (n = 72), and various environmental controls (n = 150). Sarcoidosis specimens consisted of two independent sets of formalin-fixed, paraffin-embedded lymph node biopsies, BAL, Kveim reagent, and fresh granulomatous spleen from a patient with sarcoidosis. All specimens were analyzed by bacterial 16S and fungal internal transcribed spacer ribosomal RNA gene sequencing. In addition, BAL was analyzed by shotgun sequencing of fractions enriched for viral particles, and Kveim and spleen were subjected to whole-genome shotgun sequencing. MEASUREMENTS AND MAIN RESULTS: In one tissue set, fungi in the Cladosporiaceae family were enriched in sarcoidosis compared with nonsarcoidosis tissues; in the other tissue set, we detected enrichment of several bacterial lineages in sarcoidosis but not Cladosporiaceae. BAL showed limited enrichment of Aspergillus fungi. Several microbial lineages were detected in Kveim and spleen, including Cladosporium. No microbial lineage was enriched in more than one sample type after correction for multiple comparisons. CONCLUSIONS: Metagenomic sequencing revealed enrichment of microbes in single types of sarcoidosis samples but limited concordance across sample types. Statistical analysis accounting for environmental contamination was essential to avoiding false positives.


Asunto(s)
ADN Bacteriano/análisis , Metagenoma/genética , Microbiota/genética , Sarcoidosis/genética , Sarcoidosis/microbiología , Biopsia con Aguja , Estudios de Casos y Controles , Femenino , Humanos , Inmunohistoquímica , Prueba de Kveim , Masculino , Valores de Referencia , Sarcoidosis/patología , Sensibilidad y Especificidad , Adhesión del Tejido
5.
Magn Reson Med ; 78(2): 611-624, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-27734519

RESUMEN

PURPOSE: To present a method for simultaneous acquisition of alveolar oxygen tension (PA O2 ), specific ventilation (SV), and apparent diffusion coefficient (ADC) of hyperpolarized (HP) gas in the human lung, allowing reinterpretation of the PA O2 and SV maps to produce a map of oxygen uptake (R). METHOD: An imaging scheme was designed with a series of identical normoxic HP gas wash-in breaths to measure ADC, SV, PA O2 , and R in less than 2 min. Signal dynamics were fit to an iterative recursive model that regionally solved for these parameters. This measurement was successfully performed in 12 subjects classified in three healthy, smoker, and chronic obstructive pulmonary disease (COPD) cohorts. RESULTS: The overall whole lung ADC, SV, PA O2 , and R in healthy, smoker, and COPD subjects was 0.20 ± 0.03 cm2 /s, 0.39 ± 0.06,113 ± 2 Torr, and 1.55 ± 0.35 Torr/s, respectively, in healthy subjects; 0.21 ± 0.03 cm2 /s, 0.33 ± 0.06, 115.9 ± 4 Torr, and 0.97 ± 0.2 Torr/s, respectively, in smokers; and 0.25 ± 0.06 cm2 /s, 0.23 ± 0.08, 114.8 ± 6.0Torr, and 0.94 ± 0.12 Torr/s, respectively, in subjects with COPD. Hetrogeneity of SV, PA O2 , and R were indicators of both smoking-related changes and disease, and the severity of the disease correlated with the degree of this heterogeneity. Subjects with symptoms showed reduced oxygen uptake and specific ventilation. CONCLUSION: High-resolution, nearly coregistered and quantitative measures of lung function and structure were obtained with less than 1 L of HP gas. This hybrid multibreath technique produced measures of lung function that revealed clear differences among the cohorts and subjects and were confirmed by correlations with global lung measurements. Magn Reson Med 78:611-624, 2017. © 2016 International Society for Magnetic Resonance in Medicine.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Oxígeno/metabolismo , Alveolos Pulmonares/diagnóstico por imagen , Alveolos Pulmonares/metabolismo , Tritio/metabolismo , Adulto , Contencion de la Respiración , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Respiración
6.
Radiology ; 279(3): 917-24, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26785042

RESUMEN

Purpose To assess the feasibility and optimize the accuracy of the multibreath wash-in hyperpolarized helium 3 ((3)He) approach to ventilation measurement by using magnetic resonance (MR) imaging as well as to examine the physiologic differences that this approach reveals among nonsmokers, asymptomatic smokers, and patients with chronic obstructive pulmonary disease (COPD). Materials and Methods All experiments were approved by the local institutional review board and compliant with HIPAA. Informed consent was obtained from all subjects. To measure fractional ventilation, the authors administered a series of identical normoxic hyperpolarized gas breaths to the subject; after each inspiration, an image was acquired during a short breath hold. Signal intensity buildup was fit to a recursive model that regionally solves for fractional ventilation. This measurement was successfully performed in nine subjects: three healthy nonsmokers (one man, two women; mean age, 45 years ± 4), three asymptomatic smokers (three men; mean age, 51 years ± 5), and three patients with COPD (three men; mean age, 59 years ± 5). Repeated measures analysis of variance was performed, followed by post hoc tests with Bonferroni correction, to assess the differences among the three cohorts. Results Whole-lung fractional ventilation as measured with hyperpolarized (3)He in all subjects (mean, 0.24 ± 0.06) showed a strong correlation with global fractional ventilation as measured with a gas delivery device (R(2) = 0.96, P < .001). Significant differences between the means of whole-lung fractional ventilation (F2,10 = 7.144, P = .012) and fractional ventilation heterogeneity (F2,10 = 7.639, P = .010) were detected among cohorts. In patients with COPD, the protocol revealed regions wherein fractional ventilation varied substantially over multiple breaths. Conclusion Multibreath wash-in hyperpolarized (3)He MR imaging of fractional ventilation is feasible in human subjects and demonstrates very good global (whole-lung) precision. Fractional ventilation measurement with this physiologically realistic approach reveals significant differences between patients with COPD and healthy subjects. To minimize error, several sources of potential bias must be corrected when calculating fractional ventilation. (©) RSNA, 2016 Online supplemental material is available for this article.


Asunto(s)
Helio/administración & dosificación , Procesamiento de Imagen Asistido por Computador/métodos , Pulmón/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico por imagen , Fumar/fisiopatología , Adulto , Biomarcadores/análisis , Estudios de Casos y Controles , Estudios de Factibilidad , Femenino , Helio/análisis , Humanos , Pulmón/fisiología , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Procesamiento de Señales Asistido por Computador
7.
Magn Reson Med ; 76(4): 1092-101, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-26467179

RESUMEN

PURPOSE: This study tested the ability of a multibreath hyperpolarized HP (3) He MRI protocol to increase the accuracy of regional alveolar oxygen tension (PA O2 ) measurements by lessening the influence of gas-flow artifacts. Conventional single-breath PA O2 measurement has been susceptible to error induced by intervoxel gas flow, particularly when used to study subjects with moderate-to-severe chronic obstructive pulmonary disease (COPD). METHODS: Both single-breath and multibreath PA O2 imaging schemes were implemented in seven human subjects (one healthy, three asymptomatic smokers, and three COPD). The number and location of voxels with nonphysiologic PA O2 values generated by intervoxel gas flow were compared between the two protocols. RESULTS: The multibreath scheme resulted in a significantly lower total percentage of nonphysiologic PA O2 values (6.0%) than the single-breath scheme (13.7%) (P = 0.006). PA O2 maps showed several patterns of gas-flow artifacts that were present in the single-breath protocol but mitigated by the multibreath approach. Multibreath imaging also allowed for the analysis of slow-filling areas that presented no signal after a single breath. CONCLUSION: A multibreath approach enhances the accuracy and completeness of noninvasive PA O2 measurement by significantly lessening the proportion of nonphysiologic values generated by intervoxel gas flow. Magn Reson Med 76:1092-1101, 2016. © 2015 Wiley Periodicals, Inc.


Asunto(s)
Helio/farmacocinética , Isótopos/farmacocinética , Imagen por Resonancia Magnética/métodos , Consumo de Oxígeno/fisiología , Oxígeno/metabolismo , Alveolos Pulmonares/fisiología , Intercambio Gaseoso Pulmonar/fisiología , Mecánica Respiratoria/fisiología , Administración por Inhalación , Adulto , Helio/administración & dosificación , Humanos , Isótopos/administración & dosificación , Masculino , Persona de Mediana Edad , Imagen Molecular/métodos , Radiofármacos/administración & dosificación , Radiofármacos/farmacocinética , Reproducibilidad de los Resultados , Pruebas de Función Respiratoria/métodos , Sensibilidad y Especificidad
8.
Radiology ; 277(1): 247-58, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26110668

RESUMEN

PURPOSE: To determine whether hyperpolarized helium 3 magnetic resonance (MR) imaging to measure alveolar partial pressure of oxygen (Pao2) shows sufficient test-retest repeatability and between-cohort differences to be used as a reliable technique for detection of alterations in gas exchange in asymptomatic smokers. MATERIALS AND METHODS: The protocol was approved by the local institutional review board and was HIPAA compliant. Informed consent was obtained from all subjects. Two sets of MR images were obtained 10 minutes apart in 25 subjects: 10 nonsmokers (five men, five women; mean ± standard deviation age, 50 years ± 6) and 15 smokers (seven women, eight men; mean age, 50 years ± 8). A mixed-effects model was developed to identify the regional repeatability of Pao2 measurements as an intraclass correlation coefficient. Ten smokers were matched with the 10 nonsmokers on the basis of signal-to-noise ratio (SNR). Three separate models were generated: one for nonsmokers, one for the SNR-matched smokers, and one for the five remaining smokers, who were imaged with a significantly higher SNR. RESULTS: Short-term back-to-back regional reproducibility was assessed by using intraclass correlation coefficients, which were 0.67 and 0.65 for SNR case-matched nonsmokers and smokers, respectively. Repeatability was a strong function of SNR; a 50% increase in SNR in the remaining smokers improved the intraclass correlation coefficient to 0.82. Although repeatability was not significantly different between the SNR-matched cohorts (P = .44), the smoker group showed higher spatial and temporal variability in Pao2. CONCLUSION: The short-term test-retest repeatability of hyperpolarized gas MR imaging of regional Pao2 was good. Asymptomatic smokers exhibited greater spatial and temporal variability in Pao2 than did the nonsmokers, which suggests that this parameter allows detection of small functional alterations associated with smoking.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Intercambio Gaseoso Pulmonar , Fumar/fisiopatología , Adulto , Femenino , Helio , Humanos , Isótopos , Masculino , Persona de Mediana Edad , Oxígeno , Presión Parcial , Alveolos Pulmonares , Reproducibilidad de los Resultados , Factores de Tiempo
9.
Radiology ; 274(2): 585-96, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25322340

RESUMEN

PURPOSE: To assess the ability of helium 3 ((3)He) magnetic resonance (MR) imaging of regional alveolar partial pressure of oxygen (Pao2) to depict smoking-induced functional alterations and to compare its efficacy to that of current diagnostic techniques. MATERIALS AND METHODS: This study was approved by the local institutional review board and was compliant with HIPAA. All subjects provided informed consent. A total of 43 subjects were separated into three groups: nonsmokers, asymptomatic smokers, and symptomatic smokers. All subjects underwent a Pao2 imaging session followed by clinically standard pulmonary function tests (PFTs), the 6-minute walk test, and St George Respiratory Questionnaire (SGRQ). The whole-lung mean and standard deviation of Pao2 were compared with metrics derived from PFTs, the 6-minute walk test, and the SGRQ. A logistic regression model was developed to identify the predictors of alterations to the lungs of asymptomatic smokers. RESULTS: The whole-lung standard deviation of Pao2 correlated with PFT metrics (forced expiratory volume in 1 second [FEV1]/forced vital capacity [FVC], Pearson r = -0.69, P < .001; percentage predicted FEV1, Pearson r = -0.67, P < .001; diffusing capacity of lung for carbon monoxide [Dlco], Pearson r = -0.45, P = .003), SGRQ score (Pearson r = 0.67, P < .001), and distance walked in 6 minutes (Pearson r = -0.47, P = .002). The standard deviation of Pao2 was significantly higher in asymptomatic smokers than in nonsmokers (change in the standard deviation of Pao2 = 7.59 mm Hg, P = .041) and lower when compared with symptomatic smokers (change in the standard deviation of Pao2 = 10.72 mm Hg, P = .001). A multivariate prediction model containing FEV1/FVC and the standard deviation of Pao2 (as significant predictors of subclinical changes in smokers) and Dlco (as a confounding variable) was formulated. This model resulted in an area under the receiver operating characteristic curve with a significant increase of 29.2% when compared with a prediction model based solely on nonimaging clinical tests. CONCLUSION: The (3)He MR imaging heterogeneity metric (standard deviation of Pao2) enabled the differentiation of all three study cohorts, which indicates that it can depict smoking-related functional alterations in asymptomatic current smokers.


Asunto(s)
Helio , Imagen por Resonancia Magnética/métodos , Oxígeno/fisiología , Alveolos Pulmonares/fisiopatología , Fumar/fisiopatología , Femenino , Humanos , Isótopos , Masculino , Persona de Mediana Edad , Presión Parcial , Pruebas de Función Respiratoria
10.
NMR Biomed ; 27(12): 1439-50, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25395184

RESUMEN

The purpose of this study was to evaluate whether regional alveolar oxygen tension (P(A)O2) vertical gradients imaged with hyperpolarized (3)He can identify smoking-induced pulmonary alterations. These gradients are compared with common clinical measurements including pulmonary function tests (PFTs), the six minute walk test, and the St. George's Respiratory Questionnaire. 8 healthy non-smokers, 12 asymptomatic smokers, and 7 symptomatic subjects with chronic obstructive pulmonary disease (COPD) underwent two sets of back-to-back P(A)O2 imaging acquisitions in the supine position in two opposite directions (top to bottom and bottom to top), followed by clinically standard pulmonary tests. The whole-lung mean, standard deviation (DP(A)O2) and vertical gradients of P(A)O2 along the slices were extracted, and the results were compared with clinically derived metrics. Statistical tests were performed to analyze the differences between cohorts. The anterior-posterior vertical gradients and DP(A)O2 effectively differentiated all three cohorts (p < 0.05). The average vertical gradient P(A)O2 in healthy subjects was -1.03 ± 0.51 Torr/cm toward lower values in the posterior/dependent regions. The directional gradient was absent in smokers (0.36 ± 1.22 Torr/cm) and was in the opposite direction in COPD subjects (2.18 ± 1.54 Torr/cm). The vertical gradients correlated with smoking history (p = 0.004); body mass index (p = 0.037), PFT metrics (forced expiratory volume in 1 s, p = 0.025; residual volume/total lung capacity percent predicted, p = 0.033) and with distance walked in 6 min (p = 0.009). Regional P(A)O2 data indicate that cigarette smoke induces physiological alterations that are not being detected by the most widely used physiological tests.


Asunto(s)
Helio , Imagen por Resonancia Magnética , Oxígeno/metabolismo , Alveolos Pulmonares/fisiología , Posición Supina , Adulto , Anciano , Análisis de Varianza , Estudios de Cohortes , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Marcadores de Spin
11.
Circ Cardiovasc Imaging ; 17(8): e016774, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39082134

RESUMEN

BACKGROUND: Fluorine-18 fluorodeoxyglucose (FDG) with positron emission tomography (PET) is the standard for detecting myocardial inflammation in cardiac sarcoidosis, requiring preparation with the ketogenic diet (KD) to achieve myocardial glucose suppression. Despite this, incomplete myocardial glucose suppression remains a significant issue, and strategies to reduce myocardial glucose uptake (MGU) and identify incomplete myocardial glucose suppression are required. This study sought to understand the relationship between point-of-care beta-hydroxybutyrate (BHB) and different patterns of MGU and between KD and fasting duration with MGU in patients undergoing evaluation for cardiac sarcoidosis. METHODS: We prospectively included 471 outpatients who underwent FDG-PET for cardiac sarcoidosis evaluation, followed the KD for 1 (n=100), 2 (n=29), and ≥3 days (n=342), fasted for at least 12 hours, and had BHB levels measured immediately before FDG injection. Images were classified as (1) no MGU (negative), (2) focal/multifocal (positive), (3) diffuse (nondiagnostic), or (4) nonspecific uptake (NS-MGU). RESULTS: Cardiac FDG-PET scans were interpreted as the following: 376 (79.83%) negative; 61 (12.95%) positive; 14 (2.97%) diffuse; and 20 (4.25%) NS-MGU. There was a strong negative relationship between BHB levels and MGU (P<0.0001). BHB levels increased significantly with KD duration (P<0.0001) and fasting time (P=0.0067). The combined rate of diffuse, NS-MGU, and positive scans (34%, 28%, 16%) decreased inversely with KD duration (1, 2, and ≥3 days, respectively). However, MGU was not different across different fasting times (P=0.6). Blood glucose levels were not associated with MGU (P=0.17) and only weakly associated with BHB levels (R2=0.03; P<0.001). CONCLUSIONS: We observed a strong inverse relationship between ketosis and patterns of MGU. Longer KD and fasting durations are associated with higher ketosis. However, only KD duration was associated with lower rates of MGU. Measurement of BHB levels before FDG-PET using point-of-care testing is feasible and may facilitate the management of patients referred for myocardial inflammation.


Asunto(s)
Cardiomiopatías , Fluorodesoxiglucosa F18 , Miocardio , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos , Sarcoidosis , Humanos , Masculino , Femenino , Sarcoidosis/diagnóstico por imagen , Sarcoidosis/metabolismo , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Persona de Mediana Edad , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/metabolismo , Estudios Prospectivos , Miocardio/metabolismo , Cetosis/metabolismo , Anciano , Ayuno/sangre , Dieta Cetogénica , Adulto , Valor Predictivo de las Pruebas , Ácido 3-Hidroxibutírico/sangre , Factores de Tiempo , Biomarcadores/sangre
12.
Magn Reson Med ; 70(6): 1557-66, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23382040

RESUMEN

PURPOSE: A systematic study of the short-term and long-term variability of regional alveolar partial pressure of oxygen tension (pA O2 ) measurements using (3) He magnetic resonance imaging was presented. Additionally, the repeatability of the average evaluated pA O2 was compared with that of the standard pulmonary function tests. METHODS: Pulmonary function test and pA O2 imaging were performed on 4 nonsmokers (1 M, 3 F, 56 ± 1.7 years) and 4 smokers (3 M, 1 F, 52 ± 7.5 years) during three visits over the course of 2 weeks. Two measurements were performed per visit. Variability of pA O2 was assessed using a mixed-effect model, with an intraclass correlation coefficient calculated for each group. The coefficient of variation of pA O2 over the 3-day period was also compared with the coefficient of variation of pulmonary function test results. RESULTS: Short-term regional variability based on intraclass correlation coefficient was 0.71 for nonsmokers, and 0.63 for smokers, with long-term variability significantly lower at 0.59 and 0.47, respectively. While the coefficient of variation of the average pA O2 was similar to the repeatability of the diffusing capacity of CO, it was significantly higher than that of Forced Vital Capacity (P = 0.02). CONCLUSION: Short-term and long-term pA O2 variability differences were used as an indication of true physiological changes in order to measure technical reproducibility. Smokers show higher physiologic variability and less technical reproducibility. The suggested pA O2 -imaging technique showed a reasonable regional repeatability in nonsmokers as well as the ability to detect differences between the two groups with similar reproducibility and superior discriminatory ability when compared with pulmonary function tests.


Asunto(s)
Helio , Interpretación de Imagen Asistida por Computador/métodos , Pulmón/fisiopatología , Imagen por Resonancia Magnética/métodos , Oxígeno/metabolismo , Intercambio Gaseoso Pulmonar , Fumar/fisiopatología , Medios de Contraste , Femenino , Humanos , Isótopos , Masculino , Persona de Mediana Edad , Oximetría/métodos , Consumo de Oxígeno , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Distribución Tisular
14.
Magn Reson Med ; 67(5): 1332-45, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22190347

RESUMEN

Reliable, noninvasive, and high-resolution imaging of alveolar partial pressure of oxygen (p(A)O(2)) is a potentially valuable tool in the early diagnosis of pulmonary diseases. Several techniques have been proposed for regional measurement of p(A)O(2) based on the increased depolarization rate of hyperpolarized (3) He. In this study, we explore one such technique by applying a multislice p(A)O(2) -imaging scheme that uses interleaved-slice ordering to utilize interslice time-delays more efficiently. This approach addresses the low spatial resolution and long breath-hold requirements of earlier techniques, allowing p(A)O(2) measurements to be made over the entire human lung in 10-15 s with a typical resolution of 8.3 × 8.3 × 15.6 mm(3). PO(2) measurements in a glass syringe phantom were in agreement with independent gas analysis within 4.7 ± 4.1% (R = 0.9993). The technique is demonstrated in four human subjects (healthy nonsmoker, healthy former smoker, healthy smoker, and patient with COPD), each imaged six times on 3 different days during a 2-week span. Two independent measurements were performed in each session, consisting of 12 coronal slices. The overall p(A)O(2) mean across all subjects was 95.9 ± 12.2 Torr and correlated well with end-tidal O(2) (R = 0.805, P < 0.0001). The alveolar O(2) uptake rate was consistent with the expected range of 1-2 Torr/s. Repeatable visual features were observed in p(A)O(2) maps over different days, as were characteristic differences among the subjects and gravity-dependent effects.


Asunto(s)
Helio , Imagen por Resonancia Magnética/métodos , Oxígeno/análisis , Alveolos Pulmonares/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Mecánica Respiratoria , Fumar/metabolismo , Medios de Contraste/administración & dosificación , Helio/administración & dosificación , Humanos , Isótopos/administración & dosificación , Masculino , Persona de Mediana Edad , Alveolos Pulmonares/patología , Enfermedad Pulmonar Obstructiva Crónica/patología , Fumar/patología , Distribución Tisular
15.
JACC Cardiovasc Imaging ; 15(11): 1944-1955, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36357136

RESUMEN

BACKGROUND: Patients with suspected cardiac sarcoidosis frequently undergo fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) imaging to assess disease activity at baseline and after treatment initiation. OBJECTIVES: This study investigated the effect of immunosuppressive therapy and biopsy status to achieve complete treatment response (CTR), partial treatment response (PTR), or no response (NR) on myocardial FDG-PET/CT. METHODS: This study analyzed 83 patients with suspected cardiac sarcoidosis (aged 53 ± 1.8 years, 71% were male, 69% were White, 61% had a history of biopsy-confirmed sarcoidosis) who were treatment naive, had evidence of myocardial FDG at baseline, and underwent repeat PET imaging after treatment initiation. CTR was graded visually, and PTR/NR were measured both visually and quantitatively using the total glycolytic activity. Patients were also evaluated for the occurrence of death, sustained ventricular arrhythmias, and heart failure admissions. RESULTS: Overall, 59 patients (71%) achieved CTR/PTR (30%/41%) at follow-up scan (P = 0.04). Total glycolytic activity and visual estimate of PTR/NR had excellent agreement (κ = 0.86 [95% CI: 0.72-0.99]; P < 0.0001). In patients receiving prednisone only, the highest rates of CTR/PTR were observed in patients initiated on moderate or high dose (P < 0.01). In a regression model, moderate prednisone start dose (P = 0.03) was more strongly associated with achieving CTR/PTR than was high prednisone start dose. However, the latter patients were tapered faster between start dose and follow-up scan (P < 0.01). After a median follow-up of 4.7 (IQR: 3.1-7.8) years, patients who were biopsy-proven (vs non-biopsy-proven; P = 0.029) and with preserved left ventricular function (P = 002) were less likely to experience major adverse cardiac events. Outcomes based on treatment response status (CTR vs PTR vs NR; P = 0.23) were not significantly different. CONCLUSIONS: Among patients with suspected sarcoidosis and evidence of myocardial inflammation, treatment response by serial FDG-PET was variable, but a favorable response was more common when using moderate-to-high intensity prednisone dose. Biopsy-proven individuals and those with preserved systolic function were less likely to experience adverse outcomes during follow-up.


Asunto(s)
Cardiomiopatías , Miocarditis , Sarcoidosis , Humanos , Masculino , Femenino , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos , Prednisona , Cardiomiopatías/diagnóstico por imagen , Cardiomiopatías/tratamiento farmacológico , Cardiomiopatías/patología , Valor Predictivo de las Pruebas , Sarcoidosis/diagnóstico por imagen , Sarcoidosis/tratamiento farmacológico , Sarcoidosis/patología , Tomografía de Emisión de Positrones/métodos , Terapia de Inmunosupresión
16.
J Occup Environ Med ; 62(1): 64-73, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31743304

RESUMEN

OBJECTIVE: To evaluate interaction of HLA-DPß1 and DRß1 polymorphisms with metrics of beryllium exposure, in the development of beryllium sensitization (BeS) and chronic beryllium disease (CBD). METHODS: A matched case-control study of 61 CBD, 41 BeS, and 259 controls from two beryllium-processing facilities. RESULTS: BES and CBD were significantly associated with presence of DPßE69. Dose response of exposure was not observed for the development of BES and CBD with/without adjustment for DPßE69 (P > 0.05). The DRßE71 polymorphism was more common in BeS than CBD after adjusting for exposure and maybe a protective factor (aOR 0.4, 95% CI 0.2 to 0.9) against the progression of BeS to CBD. CONCLUSION: No exposure-response association was found, which may reflect that the workers in this high exposure cohort were above a threshold level where an exposure-response could be observed.


Asunto(s)
Beriliosis/genética , Berilio/toxicidad , Exposición Profesional/estadística & datos numéricos , Estudios de Casos y Controles , Estudios de Cohortes , Cadenas beta de HLA-DP/genética , Humanos , Proteínas del Tejido Nervioso/genética , Polimorfismo Genético , Proteínas de Unión al ARN/genética
17.
Am J Respir Crit Care Med ; 177(9): 1012-7, 2008 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-18244954

RESUMEN

RATIONALE: Between 1948 and 1969, cases of community-acquired chronic beryllium disease (CA-CBD) were reported in neighborhoods surrounding beryllium facilities. Further surveillance was not performed in these communities, and additional cases have not been reported. OBJECTIVES: To increase awareness of recently diagnosed cases of CA-CBD in residents surrounding a beryllium facility. METHODS: Medical records were reviewed from individuals in a community surrounding a beryllium manufacturing facility in Reading, Pennsylvania. Definite cases of CBD required (1) an abnormal beryllium lymphocyte proliferation test in blood or bronchoalveolar lavage and (2) biopsy evidence of granulomatous inflammation. Probable cases of CBD either displayed an abnormal blood test to beryllium and radiographic evidence consistent with disease, or met epidemiologic criteria for CBD based on the Beryllium Case Registry criteria. Cases with occupational or potential paraoccupational exposure were excluded. MEASUREMENTS AND MAIN RESULTS: Sixteen cases of potential community-acquired CBD were evaluated. From these, eight cases of community-acquired CBD were identified (five definite and three probable). The cases' initial year of residence began between 1943 and 1953 and continued until 1956-2001. Six of the eight cases required medical treatment and three of the cases died since diagnosis. CONCLUSIONS: Cases of CBD meeting current immunologic diagnostic criteria and attributable to industry-associated environmental exposure were detected among residents of a community surrounding a beryllium manufacturing facility. Most were diagnosed years after exposure cessation. The frequency and extent of beryllium disease in this community are unknown. We anticipate that not only have cases been misdiagnosed in this community but that more cases of CBD will be diagnosed in the future.


Asunto(s)
Beriliosis/epidemiología , Berilio/efectos adversos , Exposición a Riesgos Ambientales/efectos adversos , Anciano , Beriliosis/diagnóstico , Beriliosis/fisiopatología , Lavado Broncoalveolar , Enfermedad Crónica , Diagnóstico Diferencial , Resultado Fatal , Femenino , Estudios de Seguimiento , Humanos , Radiografía Torácica , Pruebas de Función Respiratoria , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
19.
Hum Immunol ; 69(8): 522-5, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18601964

RESUMEN

The immensely polymorphic and gene-rich landscape of the major histocompatibility complex on chromosome 6 necessitates a thorough and consistent investigation of its constituting elements. The human leukocyte antigens (HLAs) are an example of such polymorphic elements, implicated in many immune-based diseases. So far, analyses of HLA molecules in the context of diseases have been ad hoc, frequently incomplete, and extremely cumbersome. SKDM provides a comprehensive and automated workflow for detecting and dissecting HLA associations in diseases. We created a Java application to consistently perform our proposed method of analysis of HLAs in case-control datasets. The SKDM HLA tool can test for HLA allele differences between two populations and, by retrieving amino acid sequences, evaluates each polymorphic amino acid residue or a pocket of amino acids as an independent variant. Once primary associations are identified, the program examines zygosity and tests for strongest association, interaction, and linkage disequilibrium among amino acid epitopes of the same HLA molecule or between HLA isotypes. A summary of the analysis is output in plain language. The software and a user's manual are freely available at http://sourceforge.net/projects/skdm.


Asunto(s)
Alelos , Predisposición Genética a la Enfermedad , Antígenos HLA/genética , Programas Informáticos , Humanos
20.
Eur Respir Rev ; 27(150)2018 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-30578332

RESUMEN

Imaging techniques are an essential component of the diagnostic process for interstitial lung diseases (ILDs). Chest radiography is frequently the initial indicator of an ILD, and comparison of radiographs taken at different time points can show the rate of disease progression. However, radiography provides only limited specificity and sensitivity and is primarily used to rule out other diseases, such as left heart failure. High-resolution computed tomography (HRCT) is a more sensitive method and is considered central in the diagnosis of ILDs. Abnormalities observed on HRCT can help identify specific ILDs. HRCT also can be used to evaluate the patient's prognosis, while disease progression can be assessed through serial imaging. Other imaging techniques such as positron emission tomography-computed tomography and magnetic resonance imaging have been investigated, but they are not commonly used to assess patients with ILDs. Disease severity may potentially be estimated using quantitative methods, as well as visual analysis of images. For example, comprehensive assessment of disease staging and progression in patients with ILDs requires visual analysis of pulmonary features that can be performed in parallel with quantitative analysis of the extent of fibrosis. New approaches to image analysis, including the application of machine learning, are being developed.


Asunto(s)
Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Fibrosis Pulmonar/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Diagnóstico Diferencial , Progresión de la Enfermedad , Humanos , Pulmón/fisiopatología , Enfermedades Pulmonares Intersticiales/fisiopatología , Enfermedades Pulmonares Intersticiales/terapia , Aprendizaje Automático , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Valor Predictivo de las Pruebas , Pronóstico , Fibrosis Pulmonar/fisiopatología , Fibrosis Pulmonar/terapia , Interpretación de Imagen Radiográfica Asistida por Computador , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
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