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1.
Gastroenterol. hepatol. (Ed. impr.) ; 46(5): 336-349, May. 2023. tab, ilus, graf
Article in English | IBECS | ID: ibc-220003

ABSTRACT

Background: The aim of this systematic review and meta-analysis was to determine the performance of magnetic resonance imaging (MRI) in the diagnosis of bowel inflammation and disease activity in Crohn's disease (CD). Methods: MEDLINE, Embase and Web of Science databases of biomedical literature were systematically searched to identify studies that investigated the diagnostic accuracy of MRI in diagnosing bowel inflammation and disease activity in CD by comparing it with reference standards. Quality Assessment of Diagnostic Accuracy Studies-2 tool was used to assess study quality. The summary sensitivity and specificity were estimated using the bivariate model, and hierarchical summary receiver operating characteristic (HSROC) parameters were calculated and plotted. Results: Of 5492 citations of interest, 34 articles contained the diagnostic accuracy data. Of these, results for the small bowel and the colorectum were reported separately in 19 studies and jointly by 21 studies. The meta-analytic summary sensitivity and specificity under the bivariate model were 90.9% (95% CI, 85.8%–94.2%) and 90.2% (95% CI, 81.9%–95.0%), respectively. The sensitivities and specificities of individual studies ranged from 55% to 100% and 51% to 100%, respectively. Substantial heterogeneity was observed in both sensitivity (I2=84.9%) and specificity (I2=78.8%). The HSROC curve also showed considerable heterogeneity between studies. Conclusion: Although the meta-analytic summary accuracy of MRI was high for the diagnosis of bowel inflammation in CD, the summary estimates might be unreliable due to the presence of high heterogeneity.(AU)


Antecedentes: El objetivo de esta revisión sistemática y metaanálisis fue determinar el rendimiento de la resonancia magnética nuclear (RM) en el diagnóstico de la inflamación intestinal y la actividad de la enfermedad en la enfermedad de Crohn (EC). Métodos: Se realizaron búsquedas sistemáticas en las bases de datos de literatura biomédica de MEDLINE, Embase y Web of Science para identificar estudios que investigaran la precisión diagnóstica de la RM en el diagnóstico de la inflamación intestinal y la actividad de la enfermedad en la EC comparándola con estándares de referencia. Evaluación de la calidad de los estudios de precisión diagnóstica: se utilizó la herramienta 2 para evaluar la calidad del estudio. La sensibilidad y la especificidad resumidas se estimaron mediante el modelo bivariado, y se calcularon y trazaron los parámetros de características operativas del receptor resumidas jerárquicas (HSROC). Resultados: De 5.492 citas de interés, 34 artículos contenían datos de precisión diagnóstica. De estos, los resultados para el intestino delgado y el colorrectal se informaron por separado en 19 estudios y en forma conjunta en 21 estudios. La sensibilidad y la especificidad del resumen metanalítico bajo el modelo bivariado fueron del 90,9% (IC del 95%, 85,8%-94,2%) y el 90,2% (IC del 95%, 81,9%-95,0%), respectivamente. Las sensibilidades y especificidades de los estudios individuales variaron del 55 al 100% y del 51 al 100%, respectivamente. Se observó heterogeneidad sustancial tanto en la sensibilidad (I2=84,9%) como en la especificidad (I2=78,8%). La curva HSROC también mostró una considerable heterogeneidad entre los estudios. Conclusión: Aunque la precisión del resumen metaanalítico de la RM fue alta para el diagnóstico de inflamación intestinal en la EC, las estimaciones del resumen pueden no ser confiables debido a la presencia de una gran heterogeneidad.(AU)


Subject(s)
Humans , Magnetic Resonance Spectroscopy , Crohn Disease , Inflammatory Bowel Diseases , Gastroenterology , Gastrointestinal Diseases
2.
Gastroenterol Hepatol ; 46(5): 336-349, 2023 May.
Article in English, Spanish | MEDLINE | ID: mdl-36243254

ABSTRACT

BACKGROUND: The aim of this systematic review and meta-analysis was to determine the performance of magnetic resonance imaging (MRI) in the diagnosis of bowel inflammation and disease activity in Crohn's disease (CD). METHODS: MEDLINE, Embase and Web of Science databases of biomedical literature were systematically searched to identify studies that investigated the diagnostic accuracy of MRI in diagnosing bowel inflammation and disease activity in CD by comparing it with reference standards. Quality Assessment of Diagnostic Accuracy Studies-2 tool was used to assess study quality. The summary sensitivity and specificity were estimated using the bivariate model, and hierarchical summary receiver operating characteristic (HSROC) parameters were calculated and plotted. RESULTS: Of 5492 citations of interest, 34 articles contained the diagnostic accuracy data. Of these, results for the small bowel and the colorectum were reported separately in 19 studies and jointly by 21 studies. The meta-analytic summary sensitivity and specificity under the bivariate model were 90.9% (95% CI, 85.8%-94.2%) and 90.2% (95% CI, 81.9%-95.0%), respectively. The sensitivities and specificities of individual studies ranged from 55% to 100% and 51% to 100%, respectively. Substantial heterogeneity was observed in both sensitivity (I2=84.9%) and specificity (I2=78.8%). The HSROC curve also showed considerable heterogeneity between studies. CONCLUSION: Although the meta-analytic summary accuracy of MRI was high for the diagnosis of bowel inflammation in CD, the summary estimates might be unreliable due to the presence of high heterogeneity.


Subject(s)
Crohn Disease , Humans , Crohn Disease/diagnosis , Intestines/pathology , Magnetic Resonance Imaging/methods , Intestine, Small/pathology , Inflammation/diagnostic imaging , Sensitivity and Specificity
4.
Clin Respir J ; 15(11): 1185-1193, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34288505

ABSTRACT

BACKGROUND: This study evaluates role of hyperpolarized 3 helium (3 He) MRI measured apparent diffusion coefficient (ADC) in examining pulmonary function of chronic obstructive pulmonary disease (COPD) patients. METHODS: After literature search in electronic databases, studies were selected by following precise eligibility criteria. Meta-analyses were performed to estimate mean difference in ADC between COPD patients and healthy individuals and to seek correlations between lung ADC and pulmonary function. Metaregression analyses were performed to seek relationships between ADC and age, gender, BMI, cigarette pack-years, and pulmonary function tests. RESULTS: Twenty-five studies (622 COPD patients and 469 healthy controls) were included. Lung ADC was 0.402 (95% confidence interval [CI]: 0.374, 0.429) in COPD patients and 0.228 (95% CI: 0.205, 0.252) in healthy individuals (mean difference 0.160 [95% CI: 0.127, 0.193]; p < 0.001). In metaregression, age (coefficient: 0.006; p = 0.004), pack-years (coefficient: 0.005; p = 0.018), forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio (coefficient: -1.815; p = 0.007), percent predicted diffusion capacity of carbon monoxide (DLCO) (coefficient: -0.004; p = 0.008), and percent predicted inspiratory capacity (coefficient: -0.004; p = 0.012) were significantly associated with ADC in COPD patients. In meta-analysis of correlation coefficients, ADC was significantly correlated with FEV1 (r = -0.62; p < 0.00001), FEV1/FVC (r = -0.80; p < 0.00001), DLCO (r = -0.85; p < 0.00001), functional residual capacity (r = 0.71; p < 0.00001), reserve volume (r = 0.53; p = 0.0001), and emphysema index (r = 0.89; p < 0.00001). CONCLUSION: Hyperpolarized 3 He MRI measured ADC was higher in COPD patients than in healthy individuals and was inversely associated with FEV1, FEV1/FVC, DLCO, and inspiratory capacity.


Subject(s)
Pulmonary Disease, Chronic Obstructive , Pulmonary Emphysema , Forced Expiratory Volume , Helium , Humans , Lung/diagnostic imaging , Magnetic Resonance Imaging , Pulmonary Disease, Chronic Obstructive/diagnostic imaging , Pulmonary Emphysema/diagnostic imaging
5.
J Hazard Mater ; 229-230: 245-50, 2012 Aug 30.
Article in English | MEDLINE | ID: mdl-22727393

ABSTRACT

Highly effective composite catalysts for removal of CO by catalytic oxidation have been designed through constructing active centers on the support of zeolite. Performances of the derived Pd-Fe-zeolite and Pd-Ce-zeolite composite catalysts for CO removal under different heterogeneous conditions were studied. The results indicate that the two kinds of promoted catalysts, including special chemical states of Pd and surface active oxygen, show high catalytic activities not only for the low temperature oxidation of CO, but also for CO electro-oxidation. The typical light-off temperatures of Pd-Fe-zeolite and Pd-Ce-zeolite for low temperature CO oxidation are 270 and 273 K. Their characteristic peak potentials for CO electro-oxidation are both around 0.70 V. The promotional effects are associated with the special interaction among Pd, modifier and zeolite, which can be firmly supported by the detailed characterizations using XRD, BET, XPS, TPD and TPR.


Subject(s)
Air Pollutants/chemistry , Carbon Monoxide/chemistry , Cerium/chemistry , Iron/chemistry , Palladium/chemistry , Zeolites/chemistry , Air Pollution/prevention & control , Catalysis , Oxidation-Reduction
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