PET/CT and inflammatory mediators in systemic sclerosis-associated interstitial lung disease.

OBJECTIVE: To investigate the correlation of HRCT findings with pulmonary metabolic activity in the corresponding regions using 18F-FDG PET/CT and inflammatory markers in patients with systemic sclerosis (SSc)-associated interstitial lung disease (ILD). METHODS: This was a cross-sectional study involving 23 adult patients with SSc-associated ILD without other connective tissue diseases. The study also involved 18F-FDG PET/CT, HRCT, determination of serum chemokine levels, clinical data, and pulmonary function testing. RESULTS: In this cohort of patients with long-term disease (disease duration, 11.8 ± 8.7 years), a nonspecific interstitial pneumonia pattern was found in 19 (82.6%). Honeycombing areas had higher median standardized uptake values (1.95; p = 0.85). Serum levels of soluble tumor necrosis factor receptor 1, soluble tumor necrosis factor receptor 2, C-C motif chemokine ligand 2 (CCL2), and C-X-C motif chemokine ligand 10 were higher in SSc patients than in controls. Serum levels of CCL2-a marker of fibroblast activity-were correlated with pure ground-glass opacity (GGO) areas on HRCT scans (p = 0.007). 18F-FDG PET/CT showed significant metabolic activity for all HRCT patterns. The correlation between serum CCL2 levels and GGO on HRCT scans suggests a central role of fibroblasts in these areas, adding new information towards the understanding of the mechanisms surrounding cellular and molecular elements and their expression on HRCT scans in patients with SSc-associated ILD. CONCLUSIONS: 18F-FDG PET/CT appears to be unable to differentiate the intensity of metabolic activity across HRCT patterns in chronic SSc patients. The association between CCL2 and GGO might be related to fibroblast activity in these areas; however, upregulated CCL2 expression in the lung tissue of SSc patients should be investigated in order to gain a better understanding of this association.

PET/CT and inflammatory mediators in systemic sclerosis-associated interstitial lung disease / PET/TC e mediadores inflamatórios na doença pulmonar intersticial associada à esclerose sistêmica

ABSTRACT Objective: To investigate the correlation of HRCT findings with pulmonary metabolic activity in the corresponding regions using 18F-FDG PET/CT and inflammatory markers in patients with systemic sclerosis (SSc)-associated interstitial lung disease (ILD). Methods: This was a cross-sectional study involving 23 adult patients with SSc-associated ILD without other connective tissue diseases. The study also involved 18F-FDG PET/CT, HRCT, determination of serum chemokine levels, clinical data, and pulmonary function testing. Results: In this cohort of patients with long-term disease (disease duration, 11.8 ± 8.7 years), a nonspecific interstitial pneumonia pattern was found in 19 (82.6%). Honeycombing areas had higher median standardized uptake values (1.95; p = 0.85). Serum levels of soluble tumor necrosis factor receptor 1, soluble tumor necrosis factor receptor 2, C-C motif chemokine ligand 2 (CCL2), and C-X-C motif chemokine ligand 10 were higher in SSc patients than in controls. Serum levels of CCL2-a marker of fibroblast activity-were correlated with pure ground-glass opacity (GGO) areas on HRCT scans (p = 0.007). 18F-FDG PET/CT showed significant metabolic activity for all HRCT patterns. The correlation between serum CCL2 levels and GGO on HRCT scans suggests a central role of fibroblasts in these areas, adding new information towards the understanding of the mechanisms surrounding cellular and molecular elements and their expression on HRCT scans in patients with SSc-associated ILD. Conclusions: 18F-FDG PET/CT appears to be unable to differentiate the intensity of metabolic activity across HRCT patterns in chronic SSc patients. The association between CCL2 and GGO might be related to fibroblast activity in these areas; however, upregulated CCL2 expression in the lung tissue of SSc patients should be investigated in order to gain a better understanding of this association.

RESUMO Objetivo: Investigar a correlação entre achados de TCAR e a atividade metabólica pulmonar nas regiões correspondentes por meio de PET/TC com 18F-FDG e marcadores inflamatórios em pacientes com doença pulmonar intersticial (DPI) associada à esclerose sistêmica (ES). Métodos: Estudo transversal envolvendo 23 pacientes adultos com DPI associada à ES sem outras doenças do tecido conjuntivo. O estudo também envolveu PET/TC com 18F-FDG, TCAR, dosagem sérica de quimiocinas, dados clínicos e testes de função pulmonar. Resultados: Nessa coorte de pacientes com doença de longa duração (11,8 ± 8,7 anos), 19 (82,6%) apresentaram o padrão de pneumonia intersticial não específica. A mediana dos valores padronizados de captação foi maior nas áreas de faveolamento (1,95; p = 0,85). Os níveis séricos de soluble tumor necrosis factor receptor 1, soluble tumor necrosis factor receptor 2, C-C motif chemokine ligand 2 (CCL2) e C-X-C motif chemokine ligand 10 foram maiores nos pacientes com ES que nos controles. Os níveis séricos de CCL2 - um marcador de atividade fibroblástica - correlacionaram-se com áreas de opacidade em vidro fosco (OVF) pura na TCAR (p = 0,007). A PET/TC com 18F-FDG mostrou atividade metabólica significativa para todos os padrões de TCAR. A correlação entre níveis séricos de CCL2 e OVF na TCAR sugere que os fibroblastos desempenham um papel fundamental nessas áreas, acrescentando novas informações para a compreensão dos mecanismos que envolvem elementos celulares e moleculares e sua expressão na TCAR em pacientes com DPI associada à ES. Conclusões: A PET/TC com 18F-FDG aparentemente não consegue diferenciar a intensidade da atividade metabólica nos diferentes padrões de TCAR em pacientes com ES crônica. A associação entre CCL2 e OVF pode estar relacionada à atividade fibroblástica nessas áreas; entretanto, a expressão suprarregulada de CCL2 no tecido pulmonar de pacientes com ES deve ser investigada para que se compreenda melhor essa associação.

Association between contextual and clinical factors and disability in people with chronic obstructive pulmonary disease.

Background: Chronic obstructive pulmonary disease (COPD) develops as a multifaceted and complex disorder, with clinical and functional repercussions. Objective: To investigate the association among contextual factors (personal and environmental) and clinical features and the disability of COPD patients, with emphasis on activity and social participation. Methods: A cross-sectional study with stable COPD participants (n = 47) was conducted to assess personal and clinical characteristics, activity of daily living using the London Chest Activity of Daily Living scale (LCADL), disability by the World Health Organization Disability Assessment Schedule 2.0 (WHODAS), and environmental factors by the Craig Hospital Inventory of Environmental Factors (CHIEF). Statistical analysis was performed by the multivariate method. Results: In the LCADL predictive analysis, the variables forced expiratory volume in 1 second (FEV1), dyspnea levels 3-4 by the modified Medical Research Council scale (mMRC), and active level of regular physical activity were included in the final model (adjusted R 2 = 0.523). In addition, WHODAS was influenced by CHIEF physical structure score and mMRC 1-2 and mMRC 3-4 grades (adjusted R 2 = 0.500). Conclusions: Disability is a complex in COPD patients and encompasses a prominent role of dyspnea levels in the prediction of activity and participation. Multivariate models presented clinical and contextual factors as functional predictors that included the physical structure of the environment in the determination of social participation.

Optimization and Application of Electrochemical Transducer for Detection of Specific Oligonucleotide Sequence for Mycobacterium tuberculosis.

In this study, the electropolymerization of 4-hydroxyphenylacetic acid (4-HPA) over graphite electrodes (GE) was optimized, aiming its application as a functionalized electrochemical platform for oligonucleotides immobilization. It was investigated for the number of potential cycles and the scan rate influence on the monomer electropolymerization by using cyclic voltammetry technique. It was observed that the polymeric film showed a redox response in the region of +0.53/+0.38 V and the increase in the number of cycles produces more electroactive platforms because of the better electrode coverage. On the other hand, the decrease of scan rate produces more electroactive platforms because of the occurrence of more organized coupling. Scanning electron microscopy (SEM) images showed that the number of potential cycles influences the coverage and morphology of the electrodeposited polymeric film. However, the images also showed that at different scan rates a more organized material was produced. The influence of these optimized polymerization parameters was evaluated both in the immobilization of specific oligonucleotides and in the detection of hybridization with complementary target. Poly(4-HPA)/GE platform has shown efficient and sensitive for oligonucleotides immobilization, as well as for a hybridization event with the complementary oligonucleotide in all investigated cases. The electrode was modified with 100 cycles at 75 mV/s presented the best responses in function of the amplitude at the monitored peak current values for the Methylene Blue and Ethidium Bromide intercalators. The construction of the genosensor to detect a specific oligonucleotide sequence for the Mycobacterium tuberculosis bacillus confirmed the results regarding the poly(4-HPA)/GE platform efficiency since it showed excellent sensitivity. The limit of detection and the limit of quantification was found to be 0.56 (±0.05) µM and 8.6 (±0.7) µM, respectively operating with very low solution volumes (15 µL of probe and 10 µL target). The biosensor development was possible with optimization of the probe adsorption parameters and target hybridization, which led to an improvement in the decrease of the Methylene Blue (MB) reduction signal from 14% to 34%. In addition, interference studies showed that the genosensor has satisfactory selectivity since the hybridization with a non-specific probe resulted in a signal decrease (46% lower) when compared to the specific target.